net/core/filter.c

   1 /*
   2  * Linux Socket Filter - Kernel level socket filtering
   3  *
   4  * Based on the design of the Berkeley Packet Filter. The new
   5  * internal format has been designed by PLUMgrid:
   6  *
   7  *      Copyright (c) 2011 - 2014 PLUMgrid, http://plumgrid.com
   8  *
   9  * Authors:
  10  *
  11  *      Jay Schulist <jschlst@samba.org>
  12  *      Alexei Starovoitov <ast@plumgrid.com>
  13  *      Daniel Borkmann <dborkman@redhat.com>
  14  *
  15  * This program is free software; you can redistribute it and/or
  16  * modify it under the terms of the GNU General Public License
  17  * as published by the Free Software Foundation; either version
  18  * 2 of the License, or (at your option) any later version.
  19  *
  20  * Andi Kleen - Fix a few bad bugs and races.
  21  * Kris Katterjohn - Added many additional checks in bpf_check_classic()
  22  */
  23
  24 #include <linux/module.h>
  25 #include <linux/types.h>
  26 #include <linux/mm.h>
  27 #include <linux/fcntl.h>
  28 #include <linux/socket.h>
  29 #include <linux/sock_diag.h>
  30 #include <linux/in.h>
  31 #include <linux/inet.h>
  32 #include <linux/netdevice.h>
  33 #include <linux/if_packet.h>
  34 #include <linux/if_arp.h>
  35 #include <linux/gfp.h>
  36 #include <net/inet_common.h>
  37 #include <net/ip.h>
  38 #include <net/protocol.h>
  39 #include <net/netlink.h>
  40 #include <linux/skbuff.h>
  41 #include <net/sock.h>
  42 #include <net/flow_dissector.h>
  43 #include <linux/errno.h>
  44 #include <linux/timer.h>
  45 #include <linux/uaccess.h>
  46 #include <asm/unaligned.h>
  47 #include <asm/cmpxchg.h>
  48 #include <linux/filter.h>
  49 #include <linux/ratelimit.h>
  50 #include <linux/seccomp.h>
  51 #include <linux/if_vlan.h>
  52 #include <linux/bpf.h>
  53 #include <net/sch_generic.h>
  54 #include <net/cls_cgroup.h>
  55 #include <net/dst_metadata.h>
  56 #include <net/dst.h>
  57 #include <net/sock_reuseport.h>
  58 #include <net/busy_poll.h>
  59 #include <net/tcp.h>
  60 #include <linux/bpf_trace.h>
  61
  62 /**
  63  *      sk_filter_trim_cap - run a packet through a socket filter
  64  *      @sk: sock associated with &sk_buff
  65  *      @skb: buffer to filter
  66  *      @cap: limit on how short the eBPF program may trim the packet
  67  *
  68  * Run the eBPF program and then cut skb->data to correct size returned by
  69  * the program. If pkt_len is 0 we toss packet. If skb->len is smaller
  70  * than pkt_len we keep whole skb->data. This is the socket level
  71  * wrapper to BPF_PROG_RUN. It returns 0 if the packet should
  72  * be accepted or -EPERM if the packet should be tossed.
  73  *
  74  */
  75 int sk_filter_trim_cap(struct sock *sk, struct sk_buff *skb, unsigned int cap)
  76 {
  77         int err;
  78         struct sk_filter *filter;
  79
  80         /*
  81          * If the skb was allocated from pfmemalloc reserves, only
  82          * allow SOCK_MEMALLOC sockets to use it as this socket is
  83          * helping free memory
  84          */
  85         if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC)) {
  86                 NET_INC_STATS(sock_net(sk), LINUX_MIB_PFMEMALLOCDROP);
  87                 return -ENOMEM;
  88         }
  89         err = BPF_CGROUP_RUN_PROG_INET_INGRESS(sk, skb);
  90         if (err)
  91                 return err;
  92
  93         err = security_sock_rcv_skb(sk, skb);
  94         if (err)
  95                 return err;
  96
  97         rcu_read_lock();
  98         filter = rcu_dereference(sk->sk_filter);
  99         if (filter) {
 100                 struct sock *save_sk = skb->sk;
 101                 unsigned int pkt_len;
 102
 103                 skb->sk = sk;
 104                 pkt_len = bpf_prog_run_save_cb(filter->prog, skb);
 105                 skb->sk = save_sk;
 106                 err = pkt_len ? pskb_trim(skb, max(cap, pkt_len)) : -EPERM;
 107         }
 108         rcu_read_unlock();
 109
 110         return err;
 111 }
 112 EXPORT_SYMBOL(sk_filter_trim_cap);
 113
 114 BPF_CALL_1(__skb_get_pay_offset, struct sk_buff *, skb)
 115 {
 116         return skb_get_poff(skb);
 117 }
 118
 119 BPF_CALL_3(__skb_get_nlattr, struct sk_buff *, skb, u32, a, u32, x)
 120 {
 121         struct nlattr *nla;
 122
 123         if (skb_is_nonlinear(skb))
 124                 return 0;
 125
 126         if (skb->len < sizeof(struct nlattr))
 127                 return 0;
 128
 129         if (a > skb->len - sizeof(struct nlattr))
 130                 return 0;
 131
 132         nla = nla_find((struct nlattr *) &skb->data[a], skb->len - a, x);
 133         if (nla)
 134                 return (void *) nla - (void *) skb->data;
 135
 136         return 0;
 137 }
 138
 139 BPF_CALL_3(__skb_get_nlattr_nest, struct sk_buff *, skb, u32, a, u32, x)
 140 {
 141         struct nlattr *nla;
 142
 143         if (skb_is_nonlinear(skb))
 144                 return 0;
 145
 146         if (skb->len < sizeof(struct nlattr))
 147                 return 0;
 148
 149         if (a > skb->len - sizeof(struct nlattr))
 150                 return 0;
 151
 152         nla = (struct nlattr *) &skb->data[a];
 153         if (nla->nla_len > skb->len - a)
 154                 return 0;
 155
 156         nla = nla_find_nested(nla, x);
 157         if (nla)
 158                 return (void *) nla - (void *) skb->data;
 159
 160         return 0;
 161 }
 162
 163 BPF_CALL_0(__get_raw_cpu_id)
 164 {
 165         return raw_smp_processor_id();
 166 }
 167
 168 static const struct bpf_func_proto bpf_get_raw_smp_processor_id_proto = {
 169         .func           = __get_raw_cpu_id,
 170         .gpl_only       = false,
 171         .ret_type       = RET_INTEGER,
 172 };
 173
 174 static u32 convert_skb_access(int skb_field, int dst_reg, int src_reg,
 175                               struct bpf_insn *insn_buf)
 176 {
 177         struct bpf_insn *insn = insn_buf;
 178
 179         switch (skb_field) {
 180         case SKF_AD_MARK:
 181                 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, mark) != 4);
 182
 183                 *insn++ = BPF_LDX_MEM(BPF_W, dst_reg, src_reg,
 184                                       offsetof(struct sk_buff, mark));
 185                 break;
 186
 187         case SKF_AD_PKTTYPE:
 188                 *insn++ = BPF_LDX_MEM(BPF_B, dst_reg, src_reg, PKT_TYPE_OFFSET());
 189                 *insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg, PKT_TYPE_MAX);
 190 #ifdef __BIG_ENDIAN_BITFIELD
 191                 *insn++ = BPF_ALU32_IMM(BPF_RSH, dst_reg, 5);
 192 #endif
 193                 break;
 194
 195         case SKF_AD_QUEUE:
 196                 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, queue_mapping) != 2);
 197
 198                 *insn++ = BPF_LDX_MEM(BPF_H, dst_reg, src_reg,
 199                                       offsetof(struct sk_buff, queue_mapping));
 200                 break;
 201
 202         case SKF_AD_VLAN_TAG:
 203         case SKF_AD_VLAN_TAG_PRESENT:
 204                 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, vlan_tci) != 2);
 205                 BUILD_BUG_ON(VLAN_TAG_PRESENT != 0x1000);
 206
 207                 /* dst_reg = *(u16 *) (src_reg + offsetof(vlan_tci)) */
 208                 *insn++ = BPF_LDX_MEM(BPF_H, dst_reg, src_reg,
 209                                       offsetof(struct sk_buff, vlan_tci));
 210                 if (skb_field == SKF_AD_VLAN_TAG) {
 211                         *insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg,
 212                                                 ~VLAN_TAG_PRESENT);
 213                 } else {
 214                         /* dst_reg >>= 12 */
 215                         *insn++ = BPF_ALU32_IMM(BPF_RSH, dst_reg, 12);
 216                         /* dst_reg &= 1 */
 217                         *insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg, 1);
 218                 }
 219                 break;
 220         }
 221
 222         return insn - insn_buf;
 223 }
 224
 225 static bool convert_bpf_extensions(struct sock_filter *fp,
 226                                    struct bpf_insn **insnp)
 227 {
 228         struct bpf_insn *insn = *insnp;
 229         u32 cnt;
 230
 231         switch (fp->k) {
 232         case SKF_AD_OFF + SKF_AD_PROTOCOL:
 233                 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, protocol) != 2);
 234
 235                 /* A = *(u16 *) (CTX + offsetof(protocol)) */
 236                 *insn++ = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_CTX,
 237                                       offsetof(struct sk_buff, protocol));
 238                 /* A = ntohs(A) [emitting a nop or swap16] */
 239                 *insn = BPF_ENDIAN(BPF_FROM_BE, BPF_REG_A, 16);
 240                 break;
 241
 242         case SKF_AD_OFF + SKF_AD_PKTTYPE:
 243                 cnt = convert_skb_access(SKF_AD_PKTTYPE, BPF_REG_A, BPF_REG_CTX, insn);
 244                 insn += cnt - 1;
 245                 break;
 246
 247         case SKF_AD_OFF + SKF_AD_IFINDEX:
 248         case SKF_AD_OFF + SKF_AD_HATYPE:
 249                 BUILD_BUG_ON(FIELD_SIZEOF(struct net_device, ifindex) != 4);
 250                 BUILD_BUG_ON(FIELD_SIZEOF(struct net_device, type) != 2);
 251
 252                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev),
 253                                       BPF_REG_TMP, BPF_REG_CTX,
 254                                       offsetof(struct sk_buff, dev));
 255                 /* if (tmp != 0) goto pc + 1 */
 256                 *insn++ = BPF_JMP_IMM(BPF_JNE, BPF_REG_TMP, 0, 1);
 257                 *insn++ = BPF_EXIT_INSN();
 258                 if (fp->k == SKF_AD_OFF + SKF_AD_IFINDEX)
 259                         *insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_TMP,
 260                                             offsetof(struct net_device, ifindex));
 261                 else
 262                         *insn = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_TMP,
 263                                             offsetof(struct net_device, type));
 264                 break;
 265
 266         case SKF_AD_OFF + SKF_AD_MARK:
 267                 cnt = convert_skb_access(SKF_AD_MARK, BPF_REG_A, BPF_REG_CTX, insn);
 268                 insn += cnt - 1;
 269                 break;
 270
 271         case SKF_AD_OFF + SKF_AD_RXHASH:
 272                 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, hash) != 4);
 273
 274                 *insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_CTX,
 275                                     offsetof(struct sk_buff, hash));
 276                 break;
 277
 278         case SKF_AD_OFF + SKF_AD_QUEUE:
 279                 cnt = convert_skb_access(SKF_AD_QUEUE, BPF_REG_A, BPF_REG_CTX, insn);
 280                 insn += cnt - 1;
 281                 break;
 282
 283         case SKF_AD_OFF + SKF_AD_VLAN_TAG:
 284                 cnt = convert_skb_access(SKF_AD_VLAN_TAG,
 285                                          BPF_REG_A, BPF_REG_CTX, insn);
 286                 insn += cnt - 1;
 287                 break;
 288
 289         case SKF_AD_OFF + SKF_AD_VLAN_TAG_PRESENT:
 290                 cnt = convert_skb_access(SKF_AD_VLAN_TAG_PRESENT,
 291                                          BPF_REG_A, BPF_REG_CTX, insn);
 292                 insn += cnt - 1;
 293                 break;
 294
 295         case SKF_AD_OFF + SKF_AD_VLAN_TPID:
 296                 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, vlan_proto) != 2);
 297
 298                 /* A = *(u16 *) (CTX + offsetof(vlan_proto)) */
 299                 *insn++ = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_CTX,
 300                                       offsetof(struct sk_buff, vlan_proto));
 301                 /* A = ntohs(A) [emitting a nop or swap16] */
 302                 *insn = BPF_ENDIAN(BPF_FROM_BE, BPF_REG_A, 16);
 303                 break;
 304
 305         case SKF_AD_OFF + SKF_AD_PAY_OFFSET:
 306         case SKF_AD_OFF + SKF_AD_NLATTR:
 307         case SKF_AD_OFF + SKF_AD_NLATTR_NEST:
 308         case SKF_AD_OFF + SKF_AD_CPU:
 309         case SKF_AD_OFF + SKF_AD_RANDOM:
 310                 /* arg1 = CTX */
 311                 *insn++ = BPF_MOV64_REG(BPF_REG_ARG1, BPF_REG_CTX);
 312                 /* arg2 = A */
 313                 *insn++ = BPF_MOV64_REG(BPF_REG_ARG2, BPF_REG_A);
 314                 /* arg3 = X */
 315                 *insn++ = BPF_MOV64_REG(BPF_REG_ARG3, BPF_REG_X);
 316                 /* Emit call(arg1=CTX, arg2=A, arg3=X) */
 317                 switch (fp->k) {
 318                 case SKF_AD_OFF + SKF_AD_PAY_OFFSET:
 319                         *insn = BPF_EMIT_CALL(__skb_get_pay_offset);
 320                         break;
 321                 case SKF_AD_OFF + SKF_AD_NLATTR:
 322                         *insn = BPF_EMIT_CALL(__skb_get_nlattr);
 323                         break;
 324                 case SKF_AD_OFF + SKF_AD_NLATTR_NEST:
 325                         *insn = BPF_EMIT_CALL(__skb_get_nlattr_nest);
 326                         break;
 327                 case SKF_AD_OFF + SKF_AD_CPU:
 328                         *insn = BPF_EMIT_CALL(__get_raw_cpu_id);
 329                         break;
 330                 case SKF_AD_OFF + SKF_AD_RANDOM:
 331                         *insn = BPF_EMIT_CALL(bpf_user_rnd_u32);
 332                         bpf_user_rnd_init_once();
 333                         break;
 334                 }
 335                 break;
 336
 337         case SKF_AD_OFF + SKF_AD_ALU_XOR_X:
 338                 /* A ^= X */
 339                 *insn = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_X);
 340                 break;
 341
 342         default:
 343                 /* This is just a dummy call to avoid letting the compiler
 344                  * evict __bpf_call_base() as an optimization. Placed here
 345                  * where no-one bothers.
 346                  */
 347                 BUG_ON(__bpf_call_base(0, 0, 0, 0, 0) != 0);
 348                 return false;
 349         }
 350
 351         *insnp = insn;
 352         return true;
 353 }
 354
 355 /**
 356  *      bpf_convert_filter - convert filter program
 357  *      @prog: the user passed filter program
 358  *      @len: the length of the user passed filter program
 359  *      @new_prog: allocated 'struct bpf_prog' or NULL
 360  *      @new_len: pointer to store length of converted program
 361  *
 362  * Remap 'sock_filter' style classic BPF (cBPF) instruction set to 'bpf_insn'
 363  * style extended BPF (eBPF).
 364  * Conversion workflow:
 365  *
 366  * 1) First pass for calculating the new program length:
 367  *   bpf_convert_filter(old_prog, old_len, NULL, &new_len)
 368  *
 369  * 2) 2nd pass to remap in two passes: 1st pass finds new
 370  *    jump offsets, 2nd pass remapping:
 371  *   bpf_convert_filter(old_prog, old_len, new_prog, &new_len);
 372  */
 373 static int bpf_convert_filter(struct sock_filter *prog, int len,
 374                               struct bpf_prog *new_prog, int *new_len)
 375 {
 376         int new_flen = 0, pass = 0, target, i, stack_off;
 377         struct bpf_insn *new_insn, *first_insn = NULL;
 378         struct sock_filter *fp;
 379         int *addrs = NULL;
 380         u8 bpf_src;
 381
 382         BUILD_BUG_ON(BPF_MEMWORDS * sizeof(u32) > MAX_BPF_STACK);
 383         BUILD_BUG_ON(BPF_REG_FP + 1 != MAX_BPF_REG);
 384
 385         if (len <= 0 || len > BPF_MAXINSNS)
 386                 return -EINVAL;
 387
 388         if (new_prog) {
 389                 first_insn = new_prog->insnsi;
 390                 addrs = kcalloc(len, sizeof(*addrs),
 391                                 GFP_KERNEL | __GFP_NOWARN);
 392                 if (!addrs)
 393                         return -ENOMEM;
 394         }
 395
 396 do_pass:
 397         new_insn = first_insn;
 398         fp = prog;
 399
 400         /* Classic BPF related prologue emission. */
 401         if (new_prog) {
 402                 /* Classic BPF expects A and X to be reset first. These need
 403                  * to be guaranteed to be the first two instructions.
 404                  */
 405                 *new_insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_A);
 406                 *new_insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_X, BPF_REG_X);
 407
 408                 /* All programs must keep CTX in callee saved BPF_REG_CTX.
 409                  * In eBPF case it's done by the compiler, here we need to
 410                  * do this ourself. Initial CTX is present in BPF_REG_ARG1.
 411                  */
 412                 *new_insn++ = BPF_MOV64_REG(BPF_REG_CTX, BPF_REG_ARG1);
 413         } else {
 414                 new_insn += 3;
 415         }
 416
 417         for (i = 0; i < len; fp++, i++) {
 418                 struct bpf_insn tmp_insns[6] = { };
 419                 struct bpf_insn *insn = tmp_insns;
 420
 421                 if (addrs)
 422                         addrs[i] = new_insn - first_insn;
 423
 424                 switch (fp->code) {
 425                 /* All arithmetic insns and skb loads map as-is. */
 426                 case BPF_ALU | BPF_ADD | BPF_X:
 427                 case BPF_ALU | BPF_ADD | BPF_K:
 428                 case BPF_ALU | BPF_SUB | BPF_X:
 429                 case BPF_ALU | BPF_SUB | BPF_K:
 430                 case BPF_ALU | BPF_AND | BPF_X:
 431                 case BPF_ALU | BPF_AND | BPF_K:
 432                 case BPF_ALU | BPF_OR | BPF_X:
 433                 case BPF_ALU | BPF_OR | BPF_K:
 434                 case BPF_ALU | BPF_LSH | BPF_X:
 435                 case BPF_ALU | BPF_LSH | BPF_K:
 436                 case BPF_ALU | BPF_RSH | BPF_X:
 437                 case BPF_ALU | BPF_RSH | BPF_K:
 438                 case BPF_ALU | BPF_XOR | BPF_X:
 439                 case BPF_ALU | BPF_XOR | BPF_K:
 440                 case BPF_ALU | BPF_MUL | BPF_X:
 441                 case BPF_ALU | BPF_MUL | BPF_K:
 442                 case BPF_ALU | BPF_DIV | BPF_X:
 443                 case BPF_ALU | BPF_DIV | BPF_K:
 444                 case BPF_ALU | BPF_MOD | BPF_X:
 445                 case BPF_ALU | BPF_MOD | BPF_K:
 446                 case BPF_ALU | BPF_NEG:
 447                 case BPF_LD | BPF_ABS | BPF_W:
 448                 case BPF_LD | BPF_ABS | BPF_H:
 449                 case BPF_LD | BPF_ABS | BPF_B:
 450                 case BPF_LD | BPF_IND | BPF_W:
 451                 case BPF_LD | BPF_IND | BPF_H:
 452                 case BPF_LD | BPF_IND | BPF_B:
 453                         /* Check for overloaded BPF extension and
 454                          * directly convert it if found, otherwise
 455                          * just move on with mapping.
 456                          */
 457                         if (BPF_CLASS(fp->code) == BPF_LD &&
 458                             BPF_MODE(fp->code) == BPF_ABS &&
 459                             convert_bpf_extensions(fp, &insn))
 460                                 break;
 461
 462                         if (fp->code == (BPF_ALU | BPF_DIV | BPF_X) ||
 463                             fp->code == (BPF_ALU | BPF_MOD | BPF_X)) {
 464                                 *insn++ = BPF_MOV32_REG(BPF_REG_X, BPF_REG_X);
 465                                 /* Error with exception code on div/mod by 0.
 466                                  * For cBPF programs, this was always return 0.
 467                                  */
 468                                 *insn++ = BPF_JMP_IMM(BPF_JNE, BPF_REG_X, 0, 2);
 469                                 *insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_A);
 470                                 *insn++ = BPF_EXIT_INSN();
 471                         }
 472
 473                         *insn = BPF_RAW_INSN(fp->code, BPF_REG_A, BPF_REG_X, 0, fp->k);
 474                         break;
 475
 476                 /* Jump transformation cannot use BPF block macros
 477                  * everywhere as offset calculation and target updates
 478                  * require a bit more work than the rest, i.e. jump
 479                  * opcodes map as-is, but offsets need adjustment.
 480                  */
 481
 482 #define BPF_EMIT_JMP                                                    \
 483         do {                                                            \
 484                 if (target >= len || target < 0)                        \
 485                         goto err;                                       \
 486                 insn->off = addrs ? addrs[target] - addrs[i] - 1 : 0;   \
 487                 /* Adjust pc relative offset for 2nd or 3rd insn. */    \
 488                 insn->off -= insn - tmp_insns;                          \
 489         } while (0)
 490
 491                 case BPF_JMP | BPF_JA:
 492                         target = i + fp->k + 1;
 493                         insn->code = fp->code;
 494                         BPF_EMIT_JMP;
 495                         break;
 496
 497                 case BPF_JMP | BPF_JEQ | BPF_K:
 498                 case BPF_JMP | BPF_JEQ | BPF_X:
 499                 case BPF_JMP | BPF_JSET | BPF_K:
 500                 case BPF_JMP | BPF_JSET | BPF_X:
 501                 case BPF_JMP | BPF_JGT | BPF_K:
 502                 case BPF_JMP | BPF_JGT | BPF_X:
 503                 case BPF_JMP | BPF_JGE | BPF_K:
 504                 case BPF_JMP | BPF_JGE | BPF_X:
 505                         if (BPF_SRC(fp->code) == BPF_K && (int) fp->k < 0) {
 506                                 /* BPF immediates are signed, zero extend
 507                                  * immediate into tmp register and use it
 508                                  * in compare insn.
 509                                  */
 510                                 *insn++ = BPF_MOV32_IMM(BPF_REG_TMP, fp->k);
 511
 512                                 insn->dst_reg = BPF_REG_A;
 513                                 insn->src_reg = BPF_REG_TMP;
 514                                 bpf_src = BPF_X;
 515                         } else {
 516                                 insn->dst_reg = BPF_REG_A;
 517                                 insn->imm = fp->k;
 518                                 bpf_src = BPF_SRC(fp->code);
 519                                 insn->src_reg = bpf_src == BPF_X ? BPF_REG_X : 0;
 520                         }
 521
 522                         /* Common case where 'jump_false' is next insn. */
 523                         if (fp->jf == 0) {
 524                                 insn->code = BPF_JMP | BPF_OP(fp->code) | bpf_src;
 525                                 target = i + fp->jt + 1;
 526                                 BPF_EMIT_JMP;
 527                                 break;
 528                         }
 529
 530                         /* Convert some jumps when 'jump_true' is next insn. */
 531                         if (fp->jt == 0) {
 532                                 switch (BPF_OP(fp->code)) {
 533                                 case BPF_JEQ:
 534                                         insn->code = BPF_JMP | BPF_JNE | bpf_src;
 535                                         break;
 536                                 case BPF_JGT:
 537                                         insn->code = BPF_JMP | BPF_JLE | bpf_src;
 538                                         break;
 539                                 case BPF_JGE:
 540                                         insn->code = BPF_JMP | BPF_JLT | bpf_src;
 541                                         break;
 542                                 default:
 543                                         goto jmp_rest;
 544                                 }
 545
 546                                 target = i + fp->jf + 1;
 547                                 BPF_EMIT_JMP;
 548                                 break;
 549                         }
 550 jmp_rest:
 551                         /* Other jumps are mapped into two insns: Jxx and JA. */
 552                         target = i + fp->jt + 1;
 553                         insn->code = BPF_JMP | BPF_OP(fp->code) | bpf_src;
 554                         BPF_EMIT_JMP;
 555                         insn++;
 556
 557                         insn->code = BPF_JMP | BPF_JA;
 558                         target = i + fp->jf + 1;
 559                         BPF_EMIT_JMP;
 560                         break;
 561
 562                 /* ldxb 4 * ([14] & 0xf) is remaped into 6 insns. */
 563                 case BPF_LDX | BPF_MSH | BPF_B:
 564                         /* tmp = A */
 565                         *insn++ = BPF_MOV64_REG(BPF_REG_TMP, BPF_REG_A);
 566                         /* A = BPF_R0 = *(u8 *) (skb->data + K) */
 567                         *insn++ = BPF_LD_ABS(BPF_B, fp->k);
 568                         /* A &= 0xf */
 569                         *insn++ = BPF_ALU32_IMM(BPF_AND, BPF_REG_A, 0xf);
 570                         /* A <<= 2 */
 571                         *insn++ = BPF_ALU32_IMM(BPF_LSH, BPF_REG_A, 2);
 572                         /* X = A */
 573                         *insn++ = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A);
 574                         /* A = tmp */
 575                         *insn = BPF_MOV64_REG(BPF_REG_A, BPF_REG_TMP);
 576                         break;
 577
 578                 /* RET_K is remaped into 2 insns. RET_A case doesn't need an
 579                  * extra mov as BPF_REG_0 is already mapped into BPF_REG_A.
 580                  */
 581                 case BPF_RET | BPF_A:
 582                 case BPF_RET | BPF_K:
 583                         if (BPF_RVAL(fp->code) == BPF_K)
 584                                 *insn++ = BPF_MOV32_RAW(BPF_K, BPF_REG_0,
 585                                                         0, fp->k);
 586                         *insn = BPF_EXIT_INSN();
 587                         break;
 588
 589                 /* Store to stack. */
 590                 case BPF_ST:
 591                 case BPF_STX:
 592                         stack_off = fp->k * 4  + 4;
 593                         *insn = BPF_STX_MEM(BPF_W, BPF_REG_FP, BPF_CLASS(fp->code) ==
 594                                             BPF_ST ? BPF_REG_A : BPF_REG_X,
 595                                             -stack_off);
 596                         /* check_load_and_stores() verifies that classic BPF can
 597                          * load from stack only after write, so tracking
 598                          * stack_depth for ST|STX insns is enough
 599                          */
 600                         if (new_prog && new_prog->aux->stack_depth < stack_off)
 601                                 new_prog->aux->stack_depth = stack_off;
 602                         break;
 603
 604                 /* Load from stack. */
 605                 case BPF_LD | BPF_MEM:
 606                 case BPF_LDX | BPF_MEM:
 607                         stack_off = fp->k * 4  + 4;
 608                         *insn = BPF_LDX_MEM(BPF_W, BPF_CLASS(fp->code) == BPF_LD  ?
 609                                             BPF_REG_A : BPF_REG_X, BPF_REG_FP,
 610                                             -stack_off);
 611                         break;
 612
 613                 /* A = K or X = K */
 614                 case BPF_LD | BPF_IMM:
 615                 case BPF_LDX | BPF_IMM:
 616                         *insn = BPF_MOV32_IMM(BPF_CLASS(fp->code) == BPF_LD ?
 617                                               BPF_REG_A : BPF_REG_X, fp->k);
 618                         break;
 619
 620                 /* X = A */
 621                 case BPF_MISC | BPF_TAX:
 622                         *insn = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A);
 623                         break;
 624
 625                 /* A = X */
 626                 case BPF_MISC | BPF_TXA:
 627                         *insn = BPF_MOV64_REG(BPF_REG_A, BPF_REG_X);
 628                         break;
 629
 630                 /* A = skb->len or X = skb->len */
 631                 case BPF_LD | BPF_W | BPF_LEN:
 632                 case BPF_LDX | BPF_W | BPF_LEN:
 633                         *insn = BPF_LDX_MEM(BPF_W, BPF_CLASS(fp->code) == BPF_LD ?
 634                                             BPF_REG_A : BPF_REG_X, BPF_REG_CTX,
 635                                             offsetof(struct sk_buff, len));
 636                         break;
 637
 638                 /* Access seccomp_data fields. */
 639                 case BPF_LDX | BPF_ABS | BPF_W:
 640                         /* A = *(u32 *) (ctx + K) */
 641                         *insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_CTX, fp->k);
 642                         break;
 643
 644                 /* Unknown instruction. */
 645                 default:
 646                         goto err;
 647                 }
 648
 649                 insn++;
 650                 if (new_prog)
 651                         memcpy(new_insn, tmp_insns,
 652                                sizeof(*insn) * (insn - tmp_insns));
 653                 new_insn += insn - tmp_insns;
 654         }
 655
 656         if (!new_prog) {
 657                 /* Only calculating new length. */
 658                 *new_len = new_insn - first_insn;
 659                 return 0;
 660         }
 661
 662         pass++;
 663         if (new_flen != new_insn - first_insn) {
 664                 new_flen = new_insn - first_insn;
 665                 if (pass > 2)
 666                         goto err;
 667                 goto do_pass;
 668         }
 669
 670         kfree(addrs);
 671         BUG_ON(*new_len != new_flen);
 672         return 0;
 673 err:
 674         kfree(addrs);
 675         return -EINVAL;
 676 }
 677
 678 /* Security:
 679  *
 680  * As we dont want to clear mem[] array for each packet going through
 681  * __bpf_prog_run(), we check that filter loaded by user never try to read
 682  * a cell if not previously written, and we check all branches to be sure
 683  * a malicious user doesn't try to abuse us.
 684  */
 685 static int check_load_and_stores(const struct sock_filter *filter, int flen)
 686 {
 687         u16 *masks, memvalid = 0; /* One bit per cell, 16 cells */
 688         int pc, ret = 0;
 689
 690         BUILD_BUG_ON(BPF_MEMWORDS > 16);
 691
 692         masks = kmalloc_array(flen, sizeof(*masks), GFP_KERNEL);
 693         if (!masks)
 694                 return -ENOMEM;
 695
 696         memset(masks, 0xff, flen * sizeof(*masks));
 697
 698         for (pc = 0; pc < flen; pc++) {
 699                 memvalid &= masks[pc];
 700
 701                 switch (filter[pc].code) {
 702                 case BPF_ST:
 703                 case BPF_STX:
 704                         memvalid |= (1 << filter[pc].k);
 705                         break;
 706                 case BPF_LD | BPF_MEM:
 707                 case BPF_LDX | BPF_MEM:
 708                         if (!(memvalid & (1 << filter[pc].k))) {
 709                                 ret = -EINVAL;
 710                                 goto error;
 711                         }
 712                         break;
 713                 case BPF_JMP | BPF_JA:
 714                         /* A jump must set masks on target */
 715                         masks[pc + 1 + filter[pc].k] &= memvalid;
 716                         memvalid = ~0;
 717                         break;
 718                 case BPF_JMP | BPF_JEQ | BPF_K:
 719                 case BPF_JMP | BPF_JEQ | BPF_X:
 720                 case BPF_JMP | BPF_JGE | BPF_K:
 721                 case BPF_JMP | BPF_JGE | BPF_X:
 722                 case BPF_JMP | BPF_JGT | BPF_K:
 723                 case BPF_JMP | BPF_JGT | BPF_X:
 724                 case BPF_JMP | BPF_JSET | BPF_K:
 725                 case BPF_JMP | BPF_JSET | BPF_X:
 726                         /* A jump must set masks on targets */
 727                         masks[pc + 1 + filter[pc].jt] &= memvalid;
 728                         masks[pc + 1 + filter[pc].jf] &= memvalid;
 729                         memvalid = ~0;
 730                         break;
 731                 }
 732         }
 733 error:
 734         kfree(masks);
 735         return ret;
 736 }
 737
 738 static bool chk_code_allowed(u16 code_to_probe)
 739 {
 740         static const bool codes[] = {
 741                 /* 32 bit ALU operations */
 742                 [BPF_ALU | BPF_ADD | BPF_K] = true,
 743                 [BPF_ALU | BPF_ADD | BPF_X] = true,
 744                 [BPF_ALU | BPF_SUB | BPF_K] = true,
 745                 [BPF_ALU | BPF_SUB | BPF_X] = true,
 746                 [BPF_ALU | BPF_MUL | BPF_K] = true,
 747                 [BPF_ALU | BPF_MUL | BPF_X] = true,
 748                 [BPF_ALU | BPF_DIV | BPF_K] = true,
 749                 [BPF_ALU | BPF_DIV | BPF_X] = true,
 750                 [BPF_ALU | BPF_MOD | BPF_K] = true,
 751                 [BPF_ALU | BPF_MOD | BPF_X] = true,
 752                 [BPF_ALU | BPF_AND | BPF_K] = true,
 753                 [BPF_ALU | BPF_AND | BPF_X] = true,
 754                 [BPF_ALU | BPF_OR | BPF_K] = true,
 755                 [BPF_ALU | BPF_OR | BPF_X] = true,
 756                 [BPF_ALU | BPF_XOR | BPF_K] = true,
 757                 [BPF_ALU | BPF_XOR | BPF_X] = true,
 758                 [BPF_ALU | BPF_LSH | BPF_K] = true,
 759                 [BPF_ALU | BPF_LSH | BPF_X] = true,
 760                 [BPF_ALU | BPF_RSH | BPF_K] = true,
 761                 [BPF_ALU | BPF_RSH | BPF_X] = true,
 762                 [BPF_ALU | BPF_NEG] = true,
 763                 /* Load instructions */
 764                 [BPF_LD | BPF_W | BPF_ABS] = true,
 765                 [BPF_LD | BPF_H | BPF_ABS] = true,
 766                 [BPF_LD | BPF_B | BPF_ABS] = true,
 767                 [BPF_LD | BPF_W | BPF_LEN] = true,
 768                 [BPF_LD | BPF_W | BPF_IND] = true,
 769                 [BPF_LD | BPF_H | BPF_IND] = true,
 770                 [BPF_LD | BPF_B | BPF_IND] = true,
 771                 [BPF_LD | BPF_IMM] = true,
 772                 [BPF_LD | BPF_MEM] = true,
 773                 [BPF_LDX | BPF_W | BPF_LEN] = true,
 774                 [BPF_LDX | BPF_B | BPF_MSH] = true,
 775                 [BPF_LDX | BPF_IMM] = true,
 776                 [BPF_LDX | BPF_MEM] = true,
 777                 /* Store instructions */
 778                 [BPF_ST] = true,
 779                 [BPF_STX] = true,
 780                 /* Misc instructions */
 781                 [BPF_MISC | BPF_TAX] = true,
 782                 [BPF_MISC | BPF_TXA] = true,
 783                 /* Return instructions */
 784                 [BPF_RET | BPF_K] = true,
 785                 [BPF_RET | BPF_A] = true,
 786                 /* Jump instructions */
 787                 [BPF_JMP | BPF_JA] = true,
 788                 [BPF_JMP | BPF_JEQ | BPF_K] = true,
 789                 [BPF_JMP | BPF_JEQ | BPF_X] = true,
 790                 [BPF_JMP | BPF_JGE | BPF_K] = true,
 791                 [BPF_JMP | BPF_JGE | BPF_X] = true,
 792                 [BPF_JMP | BPF_JGT | BPF_K] = true,
 793                 [BPF_JMP | BPF_JGT | BPF_X] = true,
 794                 [BPF_JMP | BPF_JSET | BPF_K] = true,
 795                 [BPF_JMP | BPF_JSET | BPF_X] = true,
 796         };
 797
 798         if (code_to_probe >= ARRAY_SIZE(codes))
 799                 return false;
 800
 801         return codes[code_to_probe];
 802 }
 803
 804 static bool bpf_check_basics_ok(const struct sock_filter *filter,
 805                                 unsigned int flen)
 806 {
 807         if (filter == NULL)
 808                 return false;
 809         if (flen == 0 || flen > BPF_MAXINSNS)
 810                 return false;
 811
 812         return true;
 813 }
 814
 815 /**
 816  *      bpf_check_classic - verify socket filter code
 817  *      @filter: filter to verify
 818  *      @flen: length of filter
 819  *
 820  * Check the user's filter code. If we let some ugly
 821  * filter code slip through kaboom! The filter must contain
 822  * no references or jumps that are out of range, no illegal
 823  * instructions, and must end with a RET instruction.
 824  *
 825  * All jumps are forward as they are not signed.
 826  *
 827  * Returns 0 if the rule set is legal or -EINVAL if not.
 828  */
 829 static int bpf_check_classic(const struct sock_filter *filter,
 830                              unsigned int flen)
 831 {
 832         bool anc_found;
 833         int pc;
 834
 835         /* Check the filter code now */
 836         for (pc = 0; pc < flen; pc++) {
 837                 const struct sock_filter *ftest = &filter[pc];
 838
 839                 /* May we actually operate on this code? */
 840                 if (!chk_code_allowed(ftest->code))
 841                         return -EINVAL;
 842
 843                 /* Some instructions need special checks */
 844                 switch (ftest->code) {
 845                 case BPF_ALU | BPF_DIV | BPF_K:
 846                 case BPF_ALU | BPF_MOD | BPF_K:
 847                         /* Check for division by zero */
 848                         if (ftest->k == 0)
 849                                 return -EINVAL;
 850                         break;
 851                 case BPF_ALU | BPF_LSH | BPF_K:
 852                 case BPF_ALU | BPF_RSH | BPF_K:
 853                         if (ftest->k >= 32)
 854                                 return -EINVAL;
 855                         break;
 856                 case BPF_LD | BPF_MEM:
 857                 case BPF_LDX | BPF_MEM:
 858                 case BPF_ST:
 859                 case BPF_STX:
 860                         /* Check for invalid memory addresses */
 861                         if (ftest->k >= BPF_MEMWORDS)
 862                                 return -EINVAL;
 863                         break;
 864                 case BPF_JMP | BPF_JA:
 865                         /* Note, the large ftest->k might cause loops.
 866                          * Compare this with conditional jumps below,
 867                          * where offsets are limited. --ANK (981016)
 868                          */
 869                         if (ftest->k >= (unsigned int)(flen - pc - 1))
 870                                 return -EINVAL;
 871                         break;
 872                 case BPF_JMP | BPF_JEQ | BPF_K:
 873                 case BPF_JMP | BPF_JEQ | BPF_X:
 874                 case BPF_JMP | BPF_JGE | BPF_K:
 875                 case BPF_JMP | BPF_JGE | BPF_X:
 876                 case BPF_JMP | BPF_JGT | BPF_K:
 877                 case BPF_JMP | BPF_JGT | BPF_X:
 878                 case BPF_JMP | BPF_JSET | BPF_K:
 879                 case BPF_JMP | BPF_JSET | BPF_X:
 880                         /* Both conditionals must be safe */
 881                         if (pc + ftest->jt + 1 >= flen ||
 882                             pc + ftest->jf + 1 >= flen)
 883                                 return -EINVAL;
 884                         break;
 885                 case BPF_LD | BPF_W | BPF_ABS:
 886                 case BPF_LD | BPF_H | BPF_ABS:
 887                 case BPF_LD | BPF_B | BPF_ABS:
 888                         anc_found = false;
 889                         if (bpf_anc_helper(ftest) & BPF_ANC)
 890                                 anc_found = true;
 891                         /* Ancillary operation unknown or unsupported */
 892                         if (anc_found == false && ftest->k >= SKF_AD_OFF)
 893                                 return -EINVAL;
 894                 }
 895         }
 896
 897         /* Last instruction must be a RET code */
 898         switch (filter[flen - 1].code) {
 899         case BPF_RET | BPF_K:
 900         case BPF_RET | BPF_A:
 901                 return check_load_and_stores(filter, flen);
 902         }
 903
 904         return -EINVAL;
 905 }
 906
 907 static int bpf_prog_store_orig_filter(struct bpf_prog *fp,
 908                                       const struct sock_fprog *fprog)
 909 {
 910         unsigned int fsize = bpf_classic_proglen(fprog);
 911         struct sock_fprog_kern *fkprog;
 912
 913         fp->orig_prog = kmalloc(sizeof(*fkprog), GFP_KERNEL);
 914         if (!fp->orig_prog)
 915                 return -ENOMEM;
 916
 917         fkprog = fp->orig_prog;
 918         fkprog->len = fprog->len;
 919
 920         fkprog->filter = kmemdup(fp->insns, fsize,
 921                                  GFP_KERNEL | __GFP_NOWARN);
 922         if (!fkprog->filter) {
 923                 kfree(fp->orig_prog);
 924                 return -ENOMEM;
 925         }
 926
 927         return 0;
 928 }
 929
 930 static void bpf_release_orig_filter(struct bpf_prog *fp)
 931 {
 932         struct sock_fprog_kern *fprog = fp->orig_prog;
 933
 934         if (fprog) {
 935                 kfree(fprog->filter);
 936                 kfree(fprog);
 937         }
 938 }
 939
 940 static void __bpf_prog_release(struct bpf_prog *prog)
 941 {
 942         if (prog->type == BPF_PROG_TYPE_SOCKET_FILTER) {
 943                 bpf_prog_put(prog);
 944         } else {
 945                 bpf_release_orig_filter(prog);
 946                 bpf_prog_free(prog);
 947         }
 948 }
 949
 950 static void __sk_filter_release(struct sk_filter *fp)
 951 {
 952         __bpf_prog_release(fp->prog);
 953         kfree(fp);
 954 }
 955
 956 /**
 957  *      sk_filter_release_rcu - Release a socket filter by rcu_head
 958  *      @rcu: rcu_head that contains the sk_filter to free
 959  */
 960 static void sk_filter_release_rcu(struct rcu_head *rcu)
 961 {
 962         struct sk_filter *fp = container_of(rcu, struct sk_filter, rcu);
 963
 964         __sk_filter_release(fp);
 965 }
 966
 967 /**
 968  *      sk_filter_release - release a socket filter
 969  *      @fp: filter to remove
 970  *
 971  *      Remove a filter from a socket and release its resources.
 972  */
 973 static void sk_filter_release(struct sk_filter *fp)
 974 {
 975         if (refcount_dec_and_test(&fp->refcnt))
 976                 call_rcu(&fp->rcu, sk_filter_release_rcu);
 977 }
 978
 979 void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp)
 980 {
 981         u32 filter_size = bpf_prog_size(fp->prog->len);
 982
 983         atomic_sub(filter_size, &sk->sk_omem_alloc);
 984         sk_filter_release(fp);
 985 }
 986
 987 /* try to charge the socket memory if there is space available
 988  * return true on success
 989  */
 990 static bool __sk_filter_charge(struct sock *sk, struct sk_filter *fp)
 991 {
 992         u32 filter_size = bpf_prog_size(fp->prog->len);
 993
 994         /* same check as in sock_kmalloc() */
 995         if (filter_size <= sysctl_optmem_max &&
 996             atomic_read(&sk->sk_omem_alloc) + filter_size < sysctl_optmem_max) {
 997                 atomic_add(filter_size, &sk->sk_omem_alloc);
 998                 return true;
 999         }
1000         return false;
1001 }
1002
1003 bool sk_filter_charge(struct sock *sk, struct sk_filter *fp)
1004 {
1005         if (!refcount_inc_not_zero(&fp->refcnt))
1006                 return false;
1007
1008         if (!__sk_filter_charge(sk, fp)) {
1009                 sk_filter_release(fp);
1010                 return false;
1011         }
1012         return true;
1013 }
1014
1015 static struct bpf_prog *bpf_migrate_filter(struct bpf_prog *fp)
1016 {
1017         struct sock_filter *old_prog;
1018         struct bpf_prog *old_fp;
1019         int err, new_len, old_len = fp->len;
1020
1021         /* We are free to overwrite insns et al right here as it
1022          * won't be used at this point in time anymore internally
1023          * after the migration to the internal BPF instruction
1024          * representation.
1025          */
1026         BUILD_BUG_ON(sizeof(struct sock_filter) !=
1027                      sizeof(struct bpf_insn));
1028
1029         /* Conversion cannot happen on overlapping memory areas,
1030          * so we need to keep the user BPF around until the 2nd
1031          * pass. At this time, the user BPF is stored in fp->insns.
1032          */
1033         old_prog = kmemdup(fp->insns, old_len * sizeof(struct sock_filter),
1034                            GFP_KERNEL | __GFP_NOWARN);
1035         if (!old_prog) {
1036                 err = -ENOMEM;
1037                 goto out_err;
1038         }
1039
1040         /* 1st pass: calculate the new program length. */
1041         err = bpf_convert_filter(old_prog, old_len, NULL, &new_len);
1042         if (err)
1043                 goto out_err_free;
1044
1045         /* Expand fp for appending the new filter representation. */
1046         old_fp = fp;
1047         fp = bpf_prog_realloc(old_fp, bpf_prog_size(new_len), 0);
1048         if (!fp) {
1049                 /* The old_fp is still around in case we couldn't
1050                  * allocate new memory, so uncharge on that one.
1051                  */
1052                 fp = old_fp;
1053                 err = -ENOMEM;
1054                 goto out_err_free;
1055         }
1056
1057         fp->len = new_len;
1058
1059         /* 2nd pass: remap sock_filter insns into bpf_insn insns. */
1060         err = bpf_convert_filter(old_prog, old_len, fp, &new_len);
1061         if (err)
1062                 /* 2nd bpf_convert_filter() can fail only if it fails
1063                  * to allocate memory, remapping must succeed. Note,
1064                  * that at this time old_fp has already been released
1065                  * by krealloc().
1066                  */
1067                 goto out_err_free;
1068
1069         fp = bpf_prog_select_runtime(fp, &err);
1070         if (err)
1071                 goto out_err_free;
1072
1073         kfree(old_prog);
1074         return fp;
1075
1076 out_err_free:
1077         kfree(old_prog);
1078 out_err:
1079         __bpf_prog_release(fp);
1080         return ERR_PTR(err);
1081 }
1082
1083 static struct bpf_prog *bpf_prepare_filter(struct bpf_prog *fp,
1084                                            bpf_aux_classic_check_t trans)
1085 {
1086         int err;
1087
1088         fp->bpf_func = NULL;
1089         fp->jited = 0;
1090
1091         err = bpf_check_classic(fp->insns, fp->len);
1092         if (err) {
1093                 __bpf_prog_release(fp);
1094                 return ERR_PTR(err);
1095         }
1096
1097         /* There might be additional checks and transformations
1098          * needed on classic filters, f.e. in case of seccomp.
1099          */
1100         if (trans) {
1101                 err = trans(fp->insns, fp->len);
1102                 if (err) {
1103                         __bpf_prog_release(fp);
1104                         return ERR_PTR(err);
1105                 }
1106         }
1107
1108         /* Probe if we can JIT compile the filter and if so, do
1109          * the compilation of the filter.
1110          */
1111         bpf_jit_compile(fp);
1112
1113         /* JIT compiler couldn't process this filter, so do the
1114          * internal BPF translation for the optimized interpreter.
1115          */
1116         if (!fp->jited)
1117                 fp = bpf_migrate_filter(fp);
1118
1119         return fp;
1120 }
1121
1122 /**
1123  *      bpf_prog_create - create an unattached filter
1124  *      @pfp: the unattached filter that is created
1125  *      @fprog: the filter program
1126  *
1127  * Create a filter independent of any socket. We first run some
1128  * sanity checks on it to make sure it does not explode on us later.
1129  * If an error occurs or there is insufficient memory for the filter
1130  * a negative errno code is returned. On success the return is zero.
1131  */
1132 int bpf_prog_create(struct bpf_prog **pfp, struct sock_fprog_kern *fprog)
1133 {
1134         unsigned int fsize = bpf_classic_proglen(fprog);
1135         struct bpf_prog *fp;
1136
1137         /* Make sure new filter is there and in the right amounts. */
1138         if (!bpf_check_basics_ok(fprog->filter, fprog->len))
1139                 return -EINVAL;
1140
1141         fp = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
1142         if (!fp)
1143                 return -ENOMEM;
1144
1145         memcpy(fp->insns, fprog->filter, fsize);
1146
1147         fp->len = fprog->len;
1148         /* Since unattached filters are not copied back to user
1149          * space through sk_get_filter(), we do not need to hold
1150          * a copy here, and can spare us the work.
1151          */
1152         fp->orig_prog = NULL;
1153
1154         /* bpf_prepare_filter() already takes care of freeing
1155          * memory in case something goes wrong.
1156          */
1157         fp = bpf_prepare_filter(fp, NULL);
1158         if (IS_ERR(fp))
1159                 return PTR_ERR(fp);
1160
1161         *pfp = fp;
1162         return 0;
1163 }
1164 EXPORT_SYMBOL_GPL(bpf_prog_create);
1165
1166 /**
1167  *      bpf_prog_create_from_user - create an unattached filter from user buffer
1168  *      @pfp: the unattached filter that is created
1169  *      @fprog: the filter program
1170  *      @trans: post-classic verifier transformation handler
1171  *      @save_orig: save classic BPF program
1172  *
1173  * This function effectively does the same as bpf_prog_create(), only
1174  * that it builds up its insns buffer from user space provided buffer.
1175  * It also allows for passing a bpf_aux_classic_check_t handler.
1176  */
1177 int bpf_prog_create_from_user(struct bpf_prog **pfp, struct sock_fprog *fprog,
1178                               bpf_aux_classic_check_t trans, bool save_orig)
1179 {
1180         unsigned int fsize = bpf_classic_proglen(fprog);
1181         struct bpf_prog *fp;
1182         int err;
1183
1184         /* Make sure new filter is there and in the right amounts. */
1185         if (!bpf_check_basics_ok(fprog->filter, fprog->len))
1186                 return -EINVAL;
1187
1188         fp = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
1189         if (!fp)
1190                 return -ENOMEM;
1191
1192         if (copy_from_user(fp->insns, fprog->filter, fsize)) {
1193                 __bpf_prog_free(fp);
1194                 return -EFAULT;
1195         }
1196
1197         fp->len = fprog->len;
1198         fp->orig_prog = NULL;
1199
1200         if (save_orig) {
1201                 err = bpf_prog_store_orig_filter(fp, fprog);
1202                 if (err) {
1203                         __bpf_prog_free(fp);
1204                         return -ENOMEM;
1205                 }
1206         }
1207
1208         /* bpf_prepare_filter() already takes care of freeing
1209          * memory in case something goes wrong.
1210          */
1211         fp = bpf_prepare_filter(fp, trans);
1212         if (IS_ERR(fp))
1213                 return PTR_ERR(fp);
1214
1215         *pfp = fp;
1216         return 0;
1217 }
1218 EXPORT_SYMBOL_GPL(bpf_prog_create_from_user);
1219
1220 void bpf_prog_destroy(struct bpf_prog *fp)
1221 {
1222         __bpf_prog_release(fp);
1223 }
1224 EXPORT_SYMBOL_GPL(bpf_prog_destroy);
1225
1226 static int __sk_attach_prog(struct bpf_prog *prog, struct sock *sk)
1227 {
1228         struct sk_filter *fp, *old_fp;
1229
1230         fp = kmalloc(sizeof(*fp), GFP_KERNEL);
1231         if (!fp)
1232                 return -ENOMEM;
1233
1234         fp->prog = prog;
1235
1236         if (!__sk_filter_charge(sk, fp)) {
1237                 kfree(fp);
1238                 return -ENOMEM;
1239         }
1240         refcount_set(&fp->refcnt, 1);
1241
1242         old_fp = rcu_dereference_protected(sk->sk_filter,
1243                                            lockdep_sock_is_held(sk));
1244         rcu_assign_pointer(sk->sk_filter, fp);
1245
1246         if (old_fp)
1247                 sk_filter_uncharge(sk, old_fp);
1248
1249         return 0;
1250 }
1251
1252 static int __reuseport_attach_prog(struct bpf_prog *prog, struct sock *sk)
1253 {
1254         struct bpf_prog *old_prog;
1255         int err;
1256
1257         if (bpf_prog_size(prog->len) > sysctl_optmem_max)
1258                 return -ENOMEM;
1259
1260         if (sk_unhashed(sk) && sk->sk_reuseport) {
1261                 err = reuseport_alloc(sk);
1262                 if (err)
1263                         return err;
1264         } else if (!rcu_access_pointer(sk->sk_reuseport_cb)) {
1265                 /* The socket wasn't bound with SO_REUSEPORT */
1266                 return -EINVAL;
1267         }
1268
1269         old_prog = reuseport_attach_prog(sk, prog);
1270         if (old_prog)
1271                 bpf_prog_destroy(old_prog);
1272
1273         return 0;
1274 }
1275
1276 static
1277 struct bpf_prog *__get_filter(struct sock_fprog *fprog, struct sock *sk)
1278 {
1279         unsigned int fsize = bpf_classic_proglen(fprog);
1280         struct bpf_prog *prog;
1281         int err;
1282
1283         if (sock_flag(sk, SOCK_FILTER_LOCKED))
1284                 return ERR_PTR(-EPERM);
1285
1286         /* Make sure new filter is there and in the right amounts. */
1287         if (!bpf_check_basics_ok(fprog->filter, fprog->len))
1288                 return ERR_PTR(-EINVAL);
1289
1290         prog = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
1291         if (!prog)
1292                 return ERR_PTR(-ENOMEM);
1293
1294         if (copy_from_user(prog->insns, fprog->filter, fsize)) {
1295                 __bpf_prog_free(prog);
1296                 return ERR_PTR(-EFAULT);
1297         }
1298
1299         prog->len = fprog->len;
1300
1301         err = bpf_prog_store_orig_filter(prog, fprog);
1302         if (err) {
1303                 __bpf_prog_free(prog);
1304                 return ERR_PTR(-ENOMEM);
1305         }
1306
1307         /* bpf_prepare_filter() already takes care of freeing
1308          * memory in case something goes wrong.
1309          */
1310         return bpf_prepare_filter(prog, NULL);
1311 }
1312
1313 /**
1314  *      sk_attach_filter - attach a socket filter
1315  *      @fprog: the filter program
1316  *      @sk: the socket to use
1317  *
1318  * Attach the user's filter code. We first run some sanity checks on
1319  * it to make sure it does not explode on us later. If an error
1320  * occurs or there is insufficient memory for the filter a negative
1321  * errno code is returned. On success the return is zero.
1322  */
1323 int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk)
1324 {
1325         struct bpf_prog *prog = __get_filter(fprog, sk);
1326         int err;
1327
1328         if (IS_ERR(prog))
1329                 return PTR_ERR(prog);
1330
1331         err = __sk_attach_prog(prog, sk);
1332         if (err < 0) {
1333                 __bpf_prog_release(prog);
1334                 return err;
1335         }
1336
1337         return 0;
1338 }
1339 EXPORT_SYMBOL_GPL(sk_attach_filter);
1340
1341 int sk_reuseport_attach_filter(struct sock_fprog *fprog, struct sock *sk)
1342 {
1343         struct bpf_prog *prog = __get_filter(fprog, sk);
1344         int err;
1345
1346         if (IS_ERR(prog))
1347                 return PTR_ERR(prog);
1348
1349         err = __reuseport_attach_prog(prog, sk);
1350         if (err < 0) {
1351                 __bpf_prog_release(prog);
1352                 return err;
1353         }
1354
1355         return 0;
1356 }
1357
1358 static struct bpf_prog *__get_bpf(u32 ufd, struct sock *sk)
1359 {
1360         if (sock_flag(sk, SOCK_FILTER_LOCKED))
1361                 return ERR_PTR(-EPERM);
1362
1363         return bpf_prog_get_type(ufd, BPF_PROG_TYPE_SOCKET_FILTER);
1364 }
1365
1366 int sk_attach_bpf(u32 ufd, struct sock *sk)
1367 {
1368         struct bpf_prog *prog = __get_bpf(ufd, sk);
1369         int err;
1370
1371         if (IS_ERR(prog))
1372                 return PTR_ERR(prog);
1373
1374         err = __sk_attach_prog(prog, sk);
1375         if (err < 0) {
1376                 bpf_prog_put(prog);
1377                 return err;
1378         }
1379
1380         return 0;
1381 }
1382
1383 int sk_reuseport_attach_bpf(u32 ufd, struct sock *sk)
1384 {
1385         struct bpf_prog *prog = __get_bpf(ufd, sk);
1386         int err;
1387
1388         if (IS_ERR(prog))
1389                 return PTR_ERR(prog);
1390
1391         err = __reuseport_attach_prog(prog, sk);
1392         if (err < 0) {
1393                 bpf_prog_put(prog);
1394                 return err;
1395         }
1396
1397         return 0;
1398 }
1399
1400 struct bpf_scratchpad {
1401         union {
1402                 __be32 diff[MAX_BPF_STACK / sizeof(__be32)];
1403                 u8     buff[MAX_BPF_STACK];
1404         };
1405 };
1406
1407 static DEFINE_PER_CPU(struct bpf_scratchpad, bpf_sp);
1408
1409 static inline int __bpf_try_make_writable(struct sk_buff *skb,
1410                                           unsigned int write_len)
1411 {
1412         return skb_ensure_writable(skb, write_len);
1413 }
1414
1415 static inline int bpf_try_make_writable(struct sk_buff *skb,
1416                                         unsigned int write_len)
1417 {
1418         int err = __bpf_try_make_writable(skb, write_len);
1419
1420         bpf_compute_data_pointers(skb);
1421         return err;
1422 }
1423
1424 static int bpf_try_make_head_writable(struct sk_buff *skb)
1425 {
1426         return bpf_try_make_writable(skb, skb_headlen(skb));
1427 }
1428
1429 static inline void bpf_push_mac_rcsum(struct sk_buff *skb)
1430 {
1431         if (skb_at_tc_ingress(skb))
1432                 skb_postpush_rcsum(skb, skb_mac_header(skb), skb->mac_len);
1433 }
1434
1435 static inline void bpf_pull_mac_rcsum(struct sk_buff *skb)
1436 {
1437         if (skb_at_tc_ingress(skb))
1438                 skb_postpull_rcsum(skb, skb_mac_header(skb), skb->mac_len);
1439 }
1440
1441 BPF_CALL_5(bpf_skb_store_bytes, struct sk_buff *, skb, u32, offset,
1442            const void *, from, u32, len, u64, flags)
1443 {
1444         void *ptr;
1445
1446         if (unlikely(flags & ~(BPF_F_RECOMPUTE_CSUM | BPF_F_INVALIDATE_HASH)))
1447                 return -EINVAL;
1448         if (unlikely(offset > 0xffff))
1449                 return -EFAULT;
1450         if (unlikely(bpf_try_make_writable(skb, offset + len)))
1451                 return -EFAULT;
1452
1453         ptr = skb->data + offset;
1454         if (flags & BPF_F_RECOMPUTE_CSUM)
1455                 __skb_postpull_rcsum(skb, ptr, len, offset);
1456
1457         memcpy(ptr, from, len);
1458
1459         if (flags & BPF_F_RECOMPUTE_CSUM)
1460                 __skb_postpush_rcsum(skb, ptr, len, offset);
1461         if (flags & BPF_F_INVALIDATE_HASH)
1462                 skb_clear_hash(skb);
1463
1464         return 0;
1465 }
1466
1467 static const struct bpf_func_proto bpf_skb_store_bytes_proto = {
1468         .func           = bpf_skb_store_bytes,
1469         .gpl_only       = false,
1470         .ret_type       = RET_INTEGER,
1471         .arg1_type      = ARG_PTR_TO_CTX,
1472         .arg2_type      = ARG_ANYTHING,
1473         .arg3_type      = ARG_PTR_TO_MEM,
1474         .arg4_type      = ARG_CONST_SIZE,
1475         .arg5_type      = ARG_ANYTHING,
1476 };
1477
1478 BPF_CALL_4(bpf_skb_load_bytes, const struct sk_buff *, skb, u32, offset,
1479            void *, to, u32, len)
1480 {
1481         void *ptr;
1482
1483         if (unlikely(offset > 0xffff))
1484                 goto err_clear;
1485
1486         ptr = skb_header_pointer(skb, offset, len, to);
1487         if (unlikely(!ptr))
1488                 goto err_clear;
1489         if (ptr != to)
1490                 memcpy(to, ptr, len);
1491
1492         return 0;
1493 err_clear:
1494         memset(to, 0, len);
1495         return -EFAULT;
1496 }
1497
1498 static const struct bpf_func_proto bpf_skb_load_bytes_proto = {
1499         .func           = bpf_skb_load_bytes,
1500         .gpl_only       = false,
1501         .ret_type       = RET_INTEGER,
1502         .arg1_type      = ARG_PTR_TO_CTX,
1503         .arg2_type      = ARG_ANYTHING,
1504         .arg3_type      = ARG_PTR_TO_UNINIT_MEM,
1505         .arg4_type      = ARG_CONST_SIZE,
1506 };
1507
1508 BPF_CALL_2(bpf_skb_pull_data, struct sk_buff *, skb, u32, len)
1509 {
1510         /* Idea is the following: should the needed direct read/write
1511          * test fail during runtime, we can pull in more data and redo
1512          * again, since implicitly, we invalidate previous checks here.
1513          *
1514          * Or, since we know how much we need to make read/writeable,
1515          * this can be done once at the program beginning for direct
1516          * access case. By this we overcome limitations of only current
1517          * headroom being accessible.
1518          */
1519         return bpf_try_make_writable(skb, len ? : skb_headlen(skb));
1520 }
1521
1522 static const struct bpf_func_proto bpf_skb_pull_data_proto = {
1523         .func           = bpf_skb_pull_data,
1524         .gpl_only       = false,
1525         .ret_type       = RET_INTEGER,
1526         .arg1_type      = ARG_PTR_TO_CTX,
1527         .arg2_type      = ARG_ANYTHING,
1528 };
1529
1530 BPF_CALL_5(bpf_l3_csum_replace, struct sk_buff *, skb, u32, offset,
1531            u64, from, u64, to, u64, flags)
1532 {
1533         __sum16 *ptr;
1534
1535         if (unlikely(flags & ~(BPF_F_HDR_FIELD_MASK)))
1536                 return -EINVAL;
1537         if (unlikely(offset > 0xffff || offset & 1))
1538                 return -EFAULT;
1539         if (unlikely(bpf_try_make_writable(skb, offset + sizeof(*ptr))))
1540                 return -EFAULT;
1541
1542         ptr = (__sum16 *)(skb->data + offset);
1543         switch (flags & BPF_F_HDR_FIELD_MASK) {
1544         case 0:
1545                 if (unlikely(from != 0))
1546                         return -EINVAL;
1547
1548                 csum_replace_by_diff(ptr, to);
1549                 break;
1550         case 2:
1551                 csum_replace2(ptr, from, to);
1552                 break;
1553         case 4:
1554                 csum_replace4(ptr, from, to);
1555                 break;
1556         default:
1557                 return -EINVAL;
1558         }
1559
1560         return 0;
1561 }
1562
1563 static const struct bpf_func_proto bpf_l3_csum_replace_proto = {
1564         .func           = bpf_l3_csum_replace,
1565         .gpl_only       = false,
1566         .ret_type       = RET_INTEGER,
1567         .arg1_type      = ARG_PTR_TO_CTX,
1568         .arg2_type      = ARG_ANYTHING,
1569         .arg3_type      = ARG_ANYTHING,
1570         .arg4_type      = ARG_ANYTHING,
1571         .arg5_type      = ARG_ANYTHING,
1572 };
1573
1574 BPF_CALL_5(bpf_l4_csum_replace, struct sk_buff *, skb, u32, offset,
1575            u64, from, u64, to, u64, flags)
1576 {
1577         bool is_pseudo = flags & BPF_F_PSEUDO_HDR;
1578         bool is_mmzero = flags & BPF_F_MARK_MANGLED_0;
1579         bool do_mforce = flags & BPF_F_MARK_ENFORCE;
1580         __sum16 *ptr;
1581
1582         if (unlikely(flags & ~(BPF_F_MARK_MANGLED_0 | BPF_F_MARK_ENFORCE |
1583                                BPF_F_PSEUDO_HDR | BPF_F_HDR_FIELD_MASK)))
1584                 return -EINVAL;
1585         if (unlikely(offset > 0xffff || offset & 1))
1586                 return -EFAULT;
1587         if (unlikely(bpf_try_make_writable(skb, offset + sizeof(*ptr))))
1588                 return -EFAULT;
1589
1590         ptr = (__sum16 *)(skb->data + offset);
1591         if (is_mmzero && !do_mforce && !*ptr)
1592                 return 0;
1593
1594         switch (flags & BPF_F_HDR_FIELD_MASK) {
1595         case 0:
1596                 if (unlikely(from != 0))
1597                         return -EINVAL;
1598
1599                 inet_proto_csum_replace_by_diff(ptr, skb, to, is_pseudo);
1600                 break;
1601         case 2:
1602                 inet_proto_csum_replace2(ptr, skb, from, to, is_pseudo);
1603                 break;
1604         case 4:
1605                 inet_proto_csum_replace4(ptr, skb, from, to, is_pseudo);
1606                 break;
1607         default:
1608                 return -EINVAL;
1609         }
1610
1611         if (is_mmzero && !*ptr)
1612                 *ptr = CSUM_MANGLED_0;
1613         return 0;
1614 }
1615
1616 static const struct bpf_func_proto bpf_l4_csum_replace_proto = {
1617         .func           = bpf_l4_csum_replace,
1618         .gpl_only       = false,
1619         .ret_type       = RET_INTEGER,
1620         .arg1_type      = ARG_PTR_TO_CTX,
1621         .arg2_type      = ARG_ANYTHING,
1622         .arg3_type      = ARG_ANYTHING,
1623         .arg4_type      = ARG_ANYTHING,
1624         .arg5_type      = ARG_ANYTHING,
1625 };
1626
1627 BPF_CALL_5(bpf_csum_diff, __be32 *, from, u32, from_size,
1628            __be32 *, to, u32, to_size, __wsum, seed)
1629 {
1630         struct bpf_scratchpad *sp = this_cpu_ptr(&bpf_sp);
1631         u32 diff_size = from_size + to_size;
1632         int i, j = 0;
1633
1634         /* This is quite flexible, some examples:
1635          *
1636          * from_size == 0, to_size > 0,  seed := csum --> pushing data
1637          * from_size > 0,  to_size == 0, seed := csum --> pulling data
1638          * from_size > 0,  to_size > 0,  seed := 0    --> diffing data
1639          *
1640          * Even for diffing, from_size and to_size don't need to be equal.
1641          */
1642         if (unlikely(((from_size | to_size) & (sizeof(__be32) - 1)) ||
1643                      diff_size > sizeof(sp->diff)))
1644                 return -EINVAL;
1645
1646         for (i = 0; i < from_size / sizeof(__be32); i++, j++)
1647                 sp->diff[j] = ~from[i];
1648         for (i = 0; i <   to_size / sizeof(__be32); i++, j++)
1649                 sp->diff[j] = to[i];
1650
1651         return csum_partial(sp->diff, diff_size, seed);
1652 }
1653
1654 static const struct bpf_func_proto bpf_csum_diff_proto = {
1655         .func           = bpf_csum_diff,
1656         .gpl_only       = false,
1657         .pkt_access     = true,
1658         .ret_type       = RET_INTEGER,
1659         .arg1_type      = ARG_PTR_TO_MEM_OR_NULL,
1660         .arg2_type      = ARG_CONST_SIZE_OR_ZERO,
1661         .arg3_type      = ARG_PTR_TO_MEM_OR_NULL,
1662         .arg4_type      = ARG_CONST_SIZE_OR_ZERO,
1663         .arg5_type      = ARG_ANYTHING,
1664 };
1665
1666 BPF_CALL_2(bpf_csum_update, struct sk_buff *, skb, __wsum, csum)
1667 {
1668         /* The interface is to be used in combination with bpf_csum_diff()
1669          * for direct packet writes. csum rotation for alignment as well
1670          * as emulating csum_sub() can be done from the eBPF program.
1671          */
1672         if (skb->ip_summed == CHECKSUM_COMPLETE)
1673                 return (skb->csum = csum_add(skb->csum, csum));
1674
1675         return -ENOTSUPP;
1676 }
1677
1678 static const struct bpf_func_proto bpf_csum_update_proto = {
1679         .func           = bpf_csum_update,
1680         .gpl_only       = false,
1681         .ret_type       = RET_INTEGER,
1682         .arg1_type      = ARG_PTR_TO_CTX,
1683         .arg2_type      = ARG_ANYTHING,
1684 };
1685
1686 static inline int __bpf_rx_skb(struct net_device *dev, struct sk_buff *skb)
1687 {
1688         return dev_forward_skb(dev, skb);
1689 }
1690
1691 static inline int __bpf_rx_skb_no_mac(struct net_device *dev,
1692                                       struct sk_buff *skb)
1693 {
1694         int ret = ____dev_forward_skb(dev, skb);
1695
1696         if (likely(!ret)) {
1697                 skb->dev = dev;
1698                 ret = netif_rx(skb);
1699         }
1700
1701         return ret;
1702 }
1703
1704 static inline int __bpf_tx_skb(struct net_device *dev, struct sk_buff *skb)
1705 {
1706         int ret;
1707
1708         if (unlikely(__this_cpu_read(xmit_recursion) > XMIT_RECURSION_LIMIT)) {
1709                 net_crit_ratelimited("bpf: recursion limit reached on datapath, buggy bpf program?\n");
1710                 kfree_skb(skb);
1711                 return -ENETDOWN;
1712         }
1713
1714         skb->dev = dev;
1715
1716         __this_cpu_inc(xmit_recursion);
1717         ret = dev_queue_xmit(skb);
1718         __this_cpu_dec(xmit_recursion);
1719
1720         return ret;
1721 }
1722
1723 static int __bpf_redirect_no_mac(struct sk_buff *skb, struct net_device *dev,
1724                                  u32 flags)
1725 {
1726         /* skb->mac_len is not set on normal egress */
1727         unsigned int mlen = skb->network_header - skb->mac_header;
1728
1729         __skb_pull(skb, mlen);
1730
1731         /* At ingress, the mac header has already been pulled once.
1732          * At egress, skb_pospull_rcsum has to be done in case that
1733          * the skb is originated from ingress (i.e. a forwarded skb)
1734          * to ensure that rcsum starts at net header.
1735          */
1736         if (!skb_at_tc_ingress(skb))
1737                 skb_postpull_rcsum(skb, skb_mac_header(skb), mlen);
1738         skb_pop_mac_header(skb);
1739         skb_reset_mac_len(skb);
1740         return flags & BPF_F_INGRESS ?
1741                __bpf_rx_skb_no_mac(dev, skb) : __bpf_tx_skb(dev, skb);
1742 }
1743
1744 static int __bpf_redirect_common(struct sk_buff *skb, struct net_device *dev,
1745                                  u32 flags)
1746 {
1747         /* Verify that a link layer header is carried */
1748         if (unlikely(skb->mac_header >= skb->network_header)) {
1749                 kfree_skb(skb);
1750                 return -ERANGE;
1751         }
1752
1753         bpf_push_mac_rcsum(skb);
1754         return flags & BPF_F_INGRESS ?
1755                __bpf_rx_skb(dev, skb) : __bpf_tx_skb(dev, skb);
1756 }
1757
1758 static int __bpf_redirect(struct sk_buff *skb, struct net_device *dev,
1759                           u32 flags)
1760 {
1761         if (dev_is_mac_header_xmit(dev))
1762                 return __bpf_redirect_common(skb, dev, flags);
1763         else
1764                 return __bpf_redirect_no_mac(skb, dev, flags);
1765 }
1766
1767 BPF_CALL_3(bpf_clone_redirect, struct sk_buff *, skb, u32, ifindex, u64, flags)
1768 {
1769         struct net_device *dev;
1770         struct sk_buff *clone;
1771         int ret;
1772
1773         if (unlikely(flags & ~(BPF_F_INGRESS)))
1774                 return -EINVAL;
1775
1776         dev = dev_get_by_index_rcu(dev_net(skb->dev), ifindex);
1777         if (unlikely(!dev))
1778                 return -EINVAL;
1779
1780         clone = skb_clone(skb, GFP_ATOMIC);
1781         if (unlikely(!clone))
1782                 return -ENOMEM;
1783
1784         /* For direct write, we need to keep the invariant that the skbs
1785          * we're dealing with need to be uncloned. Should uncloning fail
1786          * here, we need to free the just generated clone to unclone once
1787          * again.
1788          */
1789         ret = bpf_try_make_head_writable(skb);
1790         if (unlikely(ret)) {
1791                 kfree_skb(clone);
1792                 return -ENOMEM;
1793         }
1794
1795         return __bpf_redirect(clone, dev, flags);
1796 }
1797
1798 static const struct bpf_func_proto bpf_clone_redirect_proto = {
1799         .func           = bpf_clone_redirect,
1800         .gpl_only       = false,
1801         .ret_type       = RET_INTEGER,
1802         .arg1_type      = ARG_PTR_TO_CTX,
1803         .arg2_type      = ARG_ANYTHING,
1804         .arg3_type      = ARG_ANYTHING,
1805 };
1806
1807 struct redirect_info {
1808         u32 ifindex;
1809         u32 flags;
1810         struct bpf_map *map;
1811         struct bpf_map *map_to_flush;
1812         unsigned long   map_owner;
1813 };
1814
1815 static DEFINE_PER_CPU(struct redirect_info, redirect_info);
1816
1817 BPF_CALL_2(bpf_redirect, u32, ifindex, u64, flags)
1818 {
1819         struct redirect_info *ri = this_cpu_ptr(&redirect_info);
1820
1821         if (unlikely(flags & ~(BPF_F_INGRESS)))
1822                 return TC_ACT_SHOT;
1823
1824         ri->ifindex = ifindex;
1825         ri->flags = flags;
1826
1827         return TC_ACT_REDIRECT;
1828 }
1829
1830 int skb_do_redirect(struct sk_buff *skb)
1831 {
1832         struct redirect_info *ri = this_cpu_ptr(&redirect_info);
1833         struct net_device *dev;
1834
1835         dev = dev_get_by_index_rcu(dev_net(skb->dev), ri->ifindex);
1836         ri->ifindex = 0;
1837         if (unlikely(!dev)) {
1838                 kfree_skb(skb);
1839                 return -EINVAL;
1840         }
1841
1842         return __bpf_redirect(skb, dev, ri->flags);
1843 }
1844
1845 static const struct bpf_func_proto bpf_redirect_proto = {
1846         .func           = bpf_redirect,
1847         .gpl_only       = false,
1848         .ret_type       = RET_INTEGER,
1849         .arg1_type      = ARG_ANYTHING,
1850         .arg2_type      = ARG_ANYTHING,
1851 };
1852
1853 BPF_CALL_4(bpf_sk_redirect_map, struct sk_buff *, skb,
1854            struct bpf_map *, map, u32, key, u64, flags)
1855 {
1856         struct tcp_skb_cb *tcb = TCP_SKB_CB(skb);
1857
1858         /* If user passes invalid input drop the packet. */
1859         if (unlikely(flags & ~(BPF_F_INGRESS)))
1860                 return SK_DROP;
1861
1862         tcb->bpf.key = key;
1863         tcb->bpf.flags = flags;
1864         tcb->bpf.map = map;
1865
1866         return SK_PASS;
1867 }
1868
1869 struct sock *do_sk_redirect_map(struct sk_buff *skb)
1870 {
1871         struct tcp_skb_cb *tcb = TCP_SKB_CB(skb);
1872         struct sock *sk = NULL;
1873
1874         if (tcb->bpf.map) {
1875                 sk = __sock_map_lookup_elem(tcb->bpf.map, tcb->bpf.key);
1876
1877                 tcb->bpf.key = 0;
1878                 tcb->bpf.map = NULL;
1879         }
1880
1881         return sk;
1882 }
1883
1884 static const struct bpf_func_proto bpf_sk_redirect_map_proto = {
1885         .func           = bpf_sk_redirect_map,
1886         .gpl_only       = false,
1887         .ret_type       = RET_INTEGER,
1888         .arg1_type      = ARG_PTR_TO_CTX,
1889         .arg2_type      = ARG_CONST_MAP_PTR,
1890         .arg3_type      = ARG_ANYTHING,
1891         .arg4_type      = ARG_ANYTHING,
1892 };
1893
1894 BPF_CALL_4(bpf_msg_redirect_map, struct sk_msg_buff *, msg,
1895            struct bpf_map *, map, u32, key, u64, flags)
1896 {
1897         /* If user passes invalid input drop the packet. */
1898         if (unlikely(flags & ~(BPF_F_INGRESS)))
1899                 return SK_DROP;
1900
1901         msg->key = key;
1902         msg->flags = flags;
1903         msg->map = map;
1904
1905         return SK_PASS;
1906 }
1907
1908 struct sock *do_msg_redirect_map(struct sk_msg_buff *msg)
1909 {
1910         struct sock *sk = NULL;
1911
1912         if (msg->map) {
1913                 sk = __sock_map_lookup_elem(msg->map, msg->key);
1914
1915                 msg->key = 0;
1916                 msg->map = NULL;
1917         }
1918
1919         return sk;
1920 }
1921
1922 static const struct bpf_func_proto bpf_msg_redirect_map_proto = {
1923         .func           = bpf_msg_redirect_map,
1924         .gpl_only       = false,
1925         .ret_type       = RET_INTEGER,
1926         .arg1_type      = ARG_PTR_TO_CTX,
1927         .arg2_type      = ARG_CONST_MAP_PTR,
1928         .arg3_type      = ARG_ANYTHING,
1929         .arg4_type      = ARG_ANYTHING,
1930 };
1931
1932 BPF_CALL_2(bpf_msg_apply_bytes, struct sk_msg_buff *, msg, u32, bytes)
1933 {
1934         msg->apply_bytes = bytes;
1935         return 0;
1936 }
1937
1938 static const struct bpf_func_proto bpf_msg_apply_bytes_proto = {
1939         .func           = bpf_msg_apply_bytes,
1940         .gpl_only       = false,
1941         .ret_type       = RET_INTEGER,
1942         .arg1_type      = ARG_PTR_TO_CTX,
1943         .arg2_type      = ARG_ANYTHING,
1944 };
1945
1946 BPF_CALL_2(bpf_msg_cork_bytes, struct sk_msg_buff *, msg, u32, bytes)
1947 {
1948         msg->cork_bytes = bytes;
1949         return 0;
1950 }
1951
1952 static const struct bpf_func_proto bpf_msg_cork_bytes_proto = {
1953         .func           = bpf_msg_cork_bytes,
1954         .gpl_only       = false,
1955         .ret_type       = RET_INTEGER,
1956         .arg1_type      = ARG_PTR_TO_CTX,
1957         .arg2_type      = ARG_ANYTHING,
1958 };
1959
1960 BPF_CALL_4(bpf_msg_pull_data,
1961            struct sk_msg_buff *, msg, u32, start, u32, end, u64, flags)
1962 {
1963         unsigned int len = 0, offset = 0, copy = 0;
1964         struct scatterlist *sg = msg->sg_data;
1965         int first_sg, last_sg, i, shift;
1966         unsigned char *p, *to, *from;
1967         int bytes = end - start;
1968         struct page *page;
1969
1970         if (unlikely(flags || end <= start))
1971                 return -EINVAL;
1972
1973         /* First find the starting scatterlist element */
1974         i = msg->sg_start;
1975         do {
1976                 len = sg[i].length;
1977                 offset += len;
1978                 if (start < offset + len)
1979                         break;
1980                 i++;
1981                 if (i == MAX_SKB_FRAGS)
1982                         i = 0;
1983         } while (i != msg->sg_end);
1984
1985         if (unlikely(start >= offset + len))
1986                 return -EINVAL;
1987
1988         if (!msg->sg_copy[i] && bytes <= len)
1989                 goto out;
1990
1991         first_sg = i;
1992
1993         /* At this point we need to linearize multiple scatterlist
1994          * elements or a single shared page. Either way we need to
1995          * copy into a linear buffer exclusively owned by BPF. Then
1996          * place the buffer in the scatterlist and fixup the original
1997          * entries by removing the entries now in the linear buffer
1998          * and shifting the remaining entries. For now we do not try
1999          * to copy partial entries to avoid complexity of running out
2000          * of sg_entry slots. The downside is reading a single byte
2001          * will copy the entire sg entry.
2002          */
2003         do {
2004                 copy += sg[i].length;
2005                 i++;
2006                 if (i == MAX_SKB_FRAGS)
2007                         i = 0;
2008                 if (bytes < copy)
2009                         break;
2010         } while (i != msg->sg_end);
2011         last_sg = i;
2012
2013         if (unlikely(copy < end - start))
2014                 return -EINVAL;
2015
2016         page = alloc_pages(__GFP_NOWARN | GFP_ATOMIC, get_order(copy));
2017         if (unlikely(!page))
2018                 return -ENOMEM;
2019         p = page_address(page);
2020         offset = 0;
2021
2022         i = first_sg;
2023         do {
2024                 from = sg_virt(&sg[i]);
2025                 len = sg[i].length;
2026                 to = p + offset;
2027
2028                 memcpy(to, from, len);
2029                 offset += len;
2030                 sg[i].length = 0;
2031                 put_page(sg_page(&sg[i]));
2032
2033                 i++;
2034                 if (i == MAX_SKB_FRAGS)
2035                         i = 0;
2036         } while (i != last_sg);
2037
2038         sg[first_sg].length = copy;
2039         sg_set_page(&sg[first_sg], page, copy, 0);
2040
2041         /* To repair sg ring we need to shift entries. If we only
2042          * had a single entry though we can just replace it and
2043          * be done. Otherwise walk the ring and shift the entries.
2044          */
2045         shift = last_sg - first_sg - 1;
2046         if (!shift)
2047                 goto out;
2048
2049         i = first_sg + 1;
2050         do {
2051                 int move_from;
2052
2053                 if (i + shift >= MAX_SKB_FRAGS)
2054                         move_from = i + shift - MAX_SKB_FRAGS;
2055                 else
2056                         move_from = i + shift;
2057
2058                 if (move_from == msg->sg_end)
2059                         break;
2060
2061                 sg[i] = sg[move_from];
2062                 sg[move_from].length = 0;
2063                 sg[move_from].page_link = 0;
2064                 sg[move_from].offset = 0;
2065
2066                 i++;
2067                 if (i == MAX_SKB_FRAGS)
2068                         i = 0;
2069         } while (1);
2070         msg->sg_end -= shift;
2071         if (msg->sg_end < 0)
2072                 msg->sg_end += MAX_SKB_FRAGS;
2073 out:
2074         msg->data = sg_virt(&sg[i]) + start - offset;
2075         msg->data_end = msg->data + bytes;
2076
2077         return 0;
2078 }
2079
2080 static const struct bpf_func_proto bpf_msg_pull_data_proto = {
2081         .func           = bpf_msg_pull_data,
2082         .gpl_only       = false,
2083         .ret_type       = RET_INTEGER,
2084         .arg1_type      = ARG_PTR_TO_CTX,
2085         .arg2_type      = ARG_ANYTHING,
2086         .arg3_type      = ARG_ANYTHING,
2087         .arg4_type      = ARG_ANYTHING,
2088 };
2089
2090 BPF_CALL_1(bpf_get_cgroup_classid, const struct sk_buff *, skb)
2091 {
2092         return task_get_classid(skb);
2093 }
2094
2095 static const struct bpf_func_proto bpf_get_cgroup_classid_proto = {
2096         .func           = bpf_get_cgroup_classid,
2097         .gpl_only       = false,
2098         .ret_type       = RET_INTEGER,
2099         .arg1_type      = ARG_PTR_TO_CTX,
2100 };
2101
2102 BPF_CALL_1(bpf_get_route_realm, const struct sk_buff *, skb)
2103 {
2104         return dst_tclassid(skb);
2105 }
2106
2107 static const struct bpf_func_proto bpf_get_route_realm_proto = {
2108         .func           = bpf_get_route_realm,
2109         .gpl_only       = false,
2110         .ret_type       = RET_INTEGER,
2111         .arg1_type      = ARG_PTR_TO_CTX,
2112 };
2113
2114 BPF_CALL_1(bpf_get_hash_recalc, struct sk_buff *, skb)
2115 {
2116         /* If skb_clear_hash() was called due to mangling, we can
2117          * trigger SW recalculation here. Later access to hash
2118          * can then use the inline skb->hash via context directly
2119          * instead of calling this helper again.
2120          */
2121         return skb_get_hash(skb);
2122 }
2123
2124 static const struct bpf_func_proto bpf_get_hash_recalc_proto = {
2125         .func           = bpf_get_hash_recalc,
2126         .gpl_only       = false,
2127         .ret_type       = RET_INTEGER,
2128         .arg1_type      = ARG_PTR_TO_CTX,
2129 };
2130
2131 BPF_CALL_1(bpf_set_hash_invalid, struct sk_buff *, skb)
2132 {
2133         /* After all direct packet write, this can be used once for
2134          * triggering a lazy recalc on next skb_get_hash() invocation.
2135          */
2136         skb_clear_hash(skb);
2137         return 0;
2138 }
2139
2140 static const struct bpf_func_proto bpf_set_hash_invalid_proto = {
2141         .func           = bpf_set_hash_invalid,
2142         .gpl_only       = false,
2143         .ret_type       = RET_INTEGER,
2144         .arg1_type      = ARG_PTR_TO_CTX,
2145 };
2146
2147 BPF_CALL_2(bpf_set_hash, struct sk_buff *, skb, u32, hash)
2148 {
2149         /* Set user specified hash as L4(+), so that it gets returned
2150          * on skb_get_hash() call unless BPF prog later on triggers a
2151          * skb_clear_hash().
2152          */
2153         __skb_set_sw_hash(skb, hash, true);
2154         return 0;
2155 }
2156
2157 static const struct bpf_func_proto bpf_set_hash_proto = {
2158         .func           = bpf_set_hash,
2159         .gpl_only       = false,
2160         .ret_type       = RET_INTEGER,
2161         .arg1_type      = ARG_PTR_TO_CTX,
2162         .arg2_type      = ARG_ANYTHING,
2163 };
2164
2165 BPF_CALL_3(bpf_skb_vlan_push, struct sk_buff *, skb, __be16, vlan_proto,
2166            u16, vlan_tci)
2167 {
2168         int ret;
2169
2170         if (unlikely(vlan_proto != htons(ETH_P_8021Q) &&
2171                      vlan_proto != htons(ETH_P_8021AD)))
2172                 vlan_proto = htons(ETH_P_8021Q);
2173
2174         bpf_push_mac_rcsum(skb);
2175         ret = skb_vlan_push(skb, vlan_proto, vlan_tci);
2176         bpf_pull_mac_rcsum(skb);
2177
2178         bpf_compute_data_pointers(skb);
2179         return ret;
2180 }
2181
2182 const struct bpf_func_proto bpf_skb_vlan_push_proto = {
2183         .func           = bpf_skb_vlan_push,
2184         .gpl_only       = false,
2185         .ret_type       = RET_INTEGER,
2186         .arg1_type      = ARG_PTR_TO_CTX,
2187         .arg2_type      = ARG_ANYTHING,
2188         .arg3_type      = ARG_ANYTHING,
2189 };
2190 EXPORT_SYMBOL_GPL(bpf_skb_vlan_push_proto);
2191
2192 BPF_CALL_1(bpf_skb_vlan_pop, struct sk_buff *, skb)
2193 {
2194         int ret;
2195
2196         bpf_push_mac_rcsum(skb);
2197         ret = skb_vlan_pop(skb);
2198         bpf_pull_mac_rcsum(skb);
2199
2200         bpf_compute_data_pointers(skb);
2201         return ret;
2202 }
2203
2204 const struct bpf_func_proto bpf_skb_vlan_pop_proto = {
2205         .func           = bpf_skb_vlan_pop,
2206         .gpl_only       = false,
2207         .ret_type       = RET_INTEGER,
2208         .arg1_type      = ARG_PTR_TO_CTX,
2209 };
2210 EXPORT_SYMBOL_GPL(bpf_skb_vlan_pop_proto);
2211
2212 static int bpf_skb_generic_push(struct sk_buff *skb, u32 off, u32 len)
2213 {
2214         /* Caller already did skb_cow() with len as headroom,
2215          * so no need to do it here.
2216          */
2217         skb_push(skb, len);
2218         memmove(skb->data, skb->data + len, off);
2219         memset(skb->data + off, 0, len);
2220
2221         /* No skb_postpush_rcsum(skb, skb->data + off, len)
2222          * needed here as it does not change the skb->csum
2223          * result for checksum complete when summing over
2224          * zeroed blocks.
2225          */
2226         return 0;
2227 }
2228
2229 static int bpf_skb_generic_pop(struct sk_buff *skb, u32 off, u32 len)
2230 {
2231         /* skb_ensure_writable() is not needed here, as we're
2232          * already working on an uncloned skb.
2233          */
2234         if (unlikely(!pskb_may_pull(skb, off + len)))
2235                 return -ENOMEM;
2236
2237         skb_postpull_rcsum(skb, skb->data + off, len);
2238         memmove(skb->data + len, skb->data, off);
2239         __skb_pull(skb, len);
2240
2241         return 0;
2242 }
2243
2244 static int bpf_skb_net_hdr_push(struct sk_buff *skb, u32 off, u32 len)
2245 {
2246         bool trans_same = skb->transport_header == skb->network_header;
2247         int ret;
2248
2249         /* There's no need for __skb_push()/__skb_pull() pair to
2250          * get to the start of the mac header as we're guaranteed
2251          * to always start from here under eBPF.
2252          */
2253         ret = bpf_skb_generic_push(skb, off, len);
2254         if (likely(!ret)) {
2255                 skb->mac_header -= len;
2256                 skb->network_header -= len;
2257                 if (trans_same)
2258                         skb->transport_header = skb->network_header;
2259         }
2260
2261         return ret;
2262 }
2263
2264 static int bpf_skb_net_hdr_pop(struct sk_buff *skb, u32 off, u32 len)
2265 {
2266         bool trans_same = skb->transport_header == skb->network_header;
2267         int ret;
2268
2269         /* Same here, __skb_push()/__skb_pull() pair not needed. */
2270         ret = bpf_skb_generic_pop(skb, off, len);
2271         if (likely(!ret)) {
2272                 skb->mac_header += len;
2273                 skb->network_header += len;
2274                 if (trans_same)
2275                         skb->transport_header = skb->network_header;
2276         }
2277
2278         return ret;
2279 }
2280
2281 static int bpf_skb_proto_4_to_6(struct sk_buff *skb)
2282 {
2283         const u32 len_diff = sizeof(struct ipv6hdr) - sizeof(struct iphdr);
2284         u32 off = skb_mac_header_len(skb);
2285         int ret;
2286
2287         /* SCTP uses GSO_BY_FRAGS, thus cannot adjust it. */
2288         if (skb_is_gso(skb) && unlikely(skb_is_gso_sctp(skb)))
2289                 return -ENOTSUPP;
2290
2291         ret = skb_cow(skb, len_diff);
2292         if (unlikely(ret < 0))
2293                 return ret;
2294
2295         ret = bpf_skb_net_hdr_push(skb, off, len_diff);
2296         if (unlikely(ret < 0))
2297                 return ret;
2298
2299         if (skb_is_gso(skb)) {
2300                 struct skb_shared_info *shinfo = skb_shinfo(skb);
2301
2302                 /* SKB_GSO_TCPV4 needs to be changed into
2303                  * SKB_GSO_TCPV6.
2304                  */
2305                 if (shinfo->gso_type & SKB_GSO_TCPV4) {
2306                         shinfo->gso_type &= ~SKB_GSO_TCPV4;
2307                         shinfo->gso_type |=  SKB_GSO_TCPV6;
2308                 }
2309
2310                 /* Due to IPv6 header, MSS needs to be downgraded. */
2311                 skb_decrease_gso_size(shinfo, len_diff);
2312                 /* Header must be checked, and gso_segs recomputed. */
2313                 shinfo->gso_type |= SKB_GSO_DODGY;
2314                 shinfo->gso_segs = 0;
2315         }
2316
2317         skb->protocol = htons(ETH_P_IPV6);
2318         skb_clear_hash(skb);
2319
2320         return 0;
2321 }
2322
2323 static int bpf_skb_proto_6_to_4(struct sk_buff *skb)
2324 {
2325         const u32 len_diff = sizeof(struct ipv6hdr) - sizeof(struct iphdr);
2326         u32 off = skb_mac_header_len(skb);
2327         int ret;
2328
2329         /* SCTP uses GSO_BY_FRAGS, thus cannot adjust it. */
2330         if (skb_is_gso(skb) && unlikely(skb_is_gso_sctp(skb)))
2331                 return -ENOTSUPP;
2332
2333         ret = skb_unclone(skb, GFP_ATOMIC);
2334         if (unlikely(ret < 0))
2335                 return ret;
2336
2337         ret = bpf_skb_net_hdr_pop(skb, off, len_diff);
2338         if (unlikely(ret < 0))
2339                 return ret;
2340
2341         if (skb_is_gso(skb)) {
2342                 struct skb_shared_info *shinfo = skb_shinfo(skb);
2343
2344                 /* SKB_GSO_TCPV6 needs to be changed into
2345                  * SKB_GSO_TCPV4.
2346                  */
2347                 if (shinfo->gso_type & SKB_GSO_TCPV6) {
2348                         shinfo->gso_type &= ~SKB_GSO_TCPV6;
2349                         shinfo->gso_type |=  SKB_GSO_TCPV4;
2350                 }
2351
2352                 /* Due to IPv4 header, MSS can be upgraded. */
2353                 skb_increase_gso_size(shinfo, len_diff);
2354                 /* Header must be checked, and gso_segs recomputed. */
2355                 shinfo->gso_type |= SKB_GSO_DODGY;
2356                 shinfo->gso_segs = 0;
2357         }
2358
2359         skb->protocol = htons(ETH_P_IP);
2360         skb_clear_hash(skb);
2361
2362         return 0;
2363 }
2364
2365 static int bpf_skb_proto_xlat(struct sk_buff *skb, __be16 to_proto)
2366 {
2367         __be16 from_proto = skb->protocol;
2368
2369         if (from_proto == htons(ETH_P_IP) &&
2370               to_proto == htons(ETH_P_IPV6))
2371                 return bpf_skb_proto_4_to_6(skb);
2372
2373         if (from_proto == htons(ETH_P_IPV6) &&
2374               to_proto == htons(ETH_P_IP))
2375                 return bpf_skb_proto_6_to_4(skb);
2376
2377         return -ENOTSUPP;
2378 }
2379
2380 BPF_CALL_3(bpf_skb_change_proto, struct sk_buff *, skb, __be16, proto,
2381            u64, flags)
2382 {
2383         int ret;
2384
2385         if (unlikely(flags))
2386                 return -EINVAL;
2387
2388         /* General idea is that this helper does the basic groundwork
2389          * needed for changing the protocol, and eBPF program fills the
2390          * rest through bpf_skb_store_bytes(), bpf_lX_csum_replace()
2391          * and other helpers, rather than passing a raw buffer here.
2392          *
2393          * The rationale is to keep this minimal and without a need to
2394          * deal with raw packet data. F.e. even if we would pass buffers
2395          * here, the program still needs to call the bpf_lX_csum_replace()
2396          * helpers anyway. Plus, this way we keep also separation of
2397          * concerns, since f.e. bpf_skb_store_bytes() should only take
2398          * care of stores.
2399          *
2400          * Currently, additional options and extension header space are
2401          * not supported, but flags register is reserved so we can adapt
2402          * that. For offloads, we mark packet as dodgy, so that headers
2403          * need to be verified first.
2404          */
2405         ret = bpf_skb_proto_xlat(skb, proto);
2406         bpf_compute_data_pointers(skb);
2407         return ret;
2408 }
2409
2410 static const struct bpf_func_proto bpf_skb_change_proto_proto = {
2411         .func           = bpf_skb_change_proto,
2412         .gpl_only       = false,
2413         .ret_type       = RET_INTEGER,
2414         .arg1_type      = ARG_PTR_TO_CTX,
2415         .arg2_type      = ARG_ANYTHING,
2416         .arg3_type      = ARG_ANYTHING,
2417 };
2418
2419 BPF_CALL_2(bpf_skb_change_type, struct sk_buff *, skb, u32, pkt_type)
2420 {
2421         /* We only allow a restricted subset to be changed for now. */
2422         if (unlikely(!skb_pkt_type_ok(skb->pkt_type) ||
2423                      !skb_pkt_type_ok(pkt_type)))
2424                 return -EINVAL;
2425
2426         skb->pkt_type = pkt_type;
2427         return 0;
2428 }
2429
2430 static const struct bpf_func_proto bpf_skb_change_type_proto = {
2431         .func           = bpf_skb_change_type,
2432         .gpl_only       = false,
2433         .ret_type       = RET_INTEGER,
2434         .arg1_type      = ARG_PTR_TO_CTX,
2435         .arg2_type      = ARG_ANYTHING,
2436 };
2437
2438 static u32 bpf_skb_net_base_len(const struct sk_buff *skb)
2439 {
2440         switch (skb->protocol) {
2441         case htons(ETH_P_IP):
2442                 return sizeof(struct iphdr);
2443         case htons(ETH_P_IPV6):
2444                 return sizeof(struct ipv6hdr);
2445         default:
2446                 return ~0U;
2447         }
2448 }
2449
2450 static int bpf_skb_net_grow(struct sk_buff *skb, u32 len_diff)
2451 {
2452         u32 off = skb_mac_header_len(skb) + bpf_skb_net_base_len(skb);
2453         int ret;
2454
2455         /* SCTP uses GSO_BY_FRAGS, thus cannot adjust it. */
2456         if (skb_is_gso(skb) && unlikely(skb_is_gso_sctp(skb)))
2457                 return -ENOTSUPP;
2458
2459         ret = skb_cow(skb, len_diff);
2460         if (unlikely(ret < 0))
2461                 return ret;
2462
2463         ret = bpf_skb_net_hdr_push(skb, off, len_diff);
2464         if (unlikely(ret < 0))
2465                 return ret;
2466
2467         if (skb_is_gso(skb)) {
2468                 struct skb_shared_info *shinfo = skb_shinfo(skb);
2469
2470                 /* Due to header grow, MSS needs to be downgraded. */
2471                 skb_decrease_gso_size(shinfo, len_diff);
2472                 /* Header must be checked, and gso_segs recomputed. */
2473                 shinfo->gso_type |= SKB_GSO_DODGY;
2474                 shinfo->gso_segs = 0;
2475         }
2476
2477         return 0;
2478 }
2479
2480 static int bpf_skb_net_shrink(struct sk_buff *skb, u32 len_diff)
2481 {
2482         u32 off = skb_mac_header_len(skb) + bpf_skb_net_base_len(skb);
2483         int ret;
2484
2485         /* SCTP uses GSO_BY_FRAGS, thus cannot adjust it. */
2486         if (skb_is_gso(skb) && unlikely(skb_is_gso_sctp(skb)))
2487                 return -ENOTSUPP;
2488
2489         ret = skb_unclone(skb, GFP_ATOMIC);
2490         if (unlikely(ret < 0))
2491                 return ret;
2492
2493         ret = bpf_skb_net_hdr_pop(skb, off, len_diff);
2494         if (unlikely(ret < 0))
2495                 return ret;
2496
2497         if (skb_is_gso(skb)) {
2498                 struct skb_shared_info *shinfo = skb_shinfo(skb);
2499
2500                 /* Due to header shrink, MSS can be upgraded. */
2501                 skb_increase_gso_size(shinfo, len_diff);
2502                 /* Header must be checked, and gso_segs recomputed. */
2503                 shinfo->gso_type |= SKB_GSO_DODGY;
2504                 shinfo->gso_segs = 0;
2505         }
2506
2507         return 0;
2508 }
2509
2510 static u32 __bpf_skb_max_len(const struct sk_buff *skb)
2511 {
2512         return skb->dev->mtu + skb->dev->hard_header_len;
2513 }
2514
2515 static int bpf_skb_adjust_net(struct sk_buff *skb, s32 len_diff)
2516 {
2517         bool trans_same = skb->transport_header == skb->network_header;
2518         u32 len_cur, len_diff_abs = abs(len_diff);
2519         u32 len_min = bpf_skb_net_base_len(skb);
2520         u32 len_max = __bpf_skb_max_len(skb);
2521         __be16 proto = skb->protocol;
2522         bool shrink = len_diff < 0;
2523         int ret;
2524
2525         if (unlikely(len_diff_abs > 0xfffU))
2526                 return -EFAULT;
2527         if (unlikely(proto != htons(ETH_P_IP) &&
2528                      proto != htons(ETH_P_IPV6)))
2529                 return -ENOTSUPP;
2530
2531         len_cur = skb->len - skb_network_offset(skb);
2532         if (skb_transport_header_was_set(skb) && !trans_same)
2533                 len_cur = skb_network_header_len(skb);
2534         if ((shrink && (len_diff_abs >= len_cur ||
2535                         len_cur - len_diff_abs < len_min)) ||
2536             (!shrink && (skb->len + len_diff_abs > len_max &&
2537                          !skb_is_gso(skb))))
2538                 return -ENOTSUPP;
2539
2540         ret = shrink ? bpf_skb_net_shrink(skb, len_diff_abs) :
2541                        bpf_skb_net_grow(skb, len_diff_abs);
2542
2543         bpf_compute_data_pointers(skb);
2544         return ret;
2545 }
2546
2547 BPF_CALL_4(bpf_skb_adjust_room, struct sk_buff *, skb, s32, len_diff,
2548            u32, mode, u64, flags)
2549 {
2550         if (unlikely(flags))
2551                 return -EINVAL;
2552         if (likely(mode == BPF_ADJ_ROOM_NET))
2553                 return bpf_skb_adjust_net(skb, len_diff);
2554
2555         return -ENOTSUPP;
2556 }
2557
2558 static const struct bpf_func_proto bpf_skb_adjust_room_proto = {
2559         .func           = bpf_skb_adjust_room,
2560         .gpl_only       = false,
2561         .ret_type       = RET_INTEGER,
2562         .arg1_type      = ARG_PTR_TO_CTX,
2563         .arg2_type      = ARG_ANYTHING,
2564         .arg3_type      = ARG_ANYTHING,
2565         .arg4_type      = ARG_ANYTHING,
2566 };
2567
2568 static u32 __bpf_skb_min_len(const struct sk_buff *skb)
2569 {
2570         u32 min_len = skb_network_offset(skb);
2571
2572         if (skb_transport_header_was_set(skb))
2573                 min_len = skb_transport_offset(skb);
2574         if (skb->ip_summed == CHECKSUM_PARTIAL)
2575                 min_len = skb_checksum_start_offset(skb) +
2576                           skb->csum_offset + sizeof(__sum16);
2577         return min_len;
2578 }
2579
2580 static int bpf_skb_grow_rcsum(struct sk_buff *skb, unsigned int new_len)
2581 {
2582         unsigned int old_len = skb->len;
2583         int ret;
2584
2585         ret = __skb_grow_rcsum(skb, new_len);
2586         if (!ret)
2587                 memset(skb->data + old_len, 0, new_len - old_len);
2588         return ret;
2589 }
2590
2591 static int bpf_skb_trim_rcsum(struct sk_buff *skb, unsigned int new_len)
2592 {
2593         return __skb_trim_rcsum(skb, new_len);
2594 }
2595
2596 BPF_CALL_3(bpf_skb_change_tail, struct sk_buff *, skb, u32, new_len,
2597            u64, flags)
2598 {
2599         u32 max_len = __bpf_skb_max_len(skb);
2600         u32 min_len = __bpf_skb_min_len(skb);
2601         int ret;
2602
2603         if (unlikely(flags || new_len > max_len || new_len < min_len))
2604                 return -EINVAL;
2605         if (skb->encapsulation)
2606                 return -ENOTSUPP;
2607
2608         /* The basic idea of this helper is that it's performing the
2609          * needed work to either grow or trim an skb, and eBPF program
2610          * rewrites the rest via helpers like bpf_skb_store_bytes(),
2611          * bpf_lX_csum_replace() and others rather than passing a raw
2612          * buffer here. This one is a slow path helper and intended
2613          * for replies with control messages.
2614          *
2615          * Like in bpf_skb_change_proto(), we want to keep this rather
2616          * minimal and without protocol specifics so that we are able
2617          * to separate concerns as in bpf_skb_store_bytes() should only
2618          * be the one responsible for writing buffers.
2619          *
2620          * It's really expected to be a slow path operation here for
2621          * control message replies, so we're implicitly linearizing,
2622          * uncloning and drop offloads from the skb by this.
2623          */
2624         ret = __bpf_try_make_writable(skb, skb->len);
2625         if (!ret) {
2626                 if (new_len > skb->len)
2627                         ret = bpf_skb_grow_rcsum(skb, new_len);
2628                 else if (new_len < skb->len)
2629                         ret = bpf_skb_trim_rcsum(skb, new_len);
2630                 if (!ret && skb_is_gso(skb))
2631                         skb_gso_reset(skb);
2632         }
2633
2634         bpf_compute_data_pointers(skb);
2635         return ret;
2636 }
2637
2638 static const struct bpf_func_proto bpf_skb_change_tail_proto = {
2639         .func           = bpf_skb_change_tail,
2640         .gpl_only       = false,
2641         .ret_type       = RET_INTEGER,
2642         .arg1_type      = ARG_PTR_TO_CTX,
2643         .arg2_type      = ARG_ANYTHING,
2644         .arg3_type      = ARG_ANYTHING,
2645 };
2646
2647 BPF_CALL_3(bpf_skb_change_head, struct sk_buff *, skb, u32, head_room,
2648            u64, flags)
2649 {
2650         u32 max_len = __bpf_skb_max_len(skb);
2651         u32 new_len = skb->len + head_room;
2652         int ret;
2653
2654         if (unlikely(flags || (!skb_is_gso(skb) && new_len > max_len) ||
2655                      new_len < skb->len))
2656                 return -EINVAL;
2657
2658         ret = skb_cow(skb, head_room);
2659         if (likely(!ret)) {
2660                 /* Idea for this helper is that we currently only
2661                  * allow to expand on mac header. This means that
2662                  * skb->protocol network header, etc, stay as is.
2663                  * Compared to bpf_skb_change_tail(), we're more
2664                  * flexible due to not needing to linearize or
2665                  * reset GSO. Intention for this helper is to be
2666                  * used by an L3 skb that needs to push mac header
2667                  * for redirection into L2 device.
2668                  */
2669                 __skb_push(skb, head_room);
2670                 memset(skb->data, 0, head_room);
2671                 skb_reset_mac_header(skb);
2672         }
2673
2674         bpf_compute_data_pointers(skb);
2675         return 0;
2676 }
2677
2678 static const struct bpf_func_proto bpf_skb_change_head_proto = {
2679         .func           = bpf_skb_change_head,
2680         .gpl_only       = false,
2681         .ret_type       = RET_INTEGER,
2682         .arg1_type      = ARG_PTR_TO_CTX,
2683         .arg2_type      = ARG_ANYTHING,
2684         .arg3_type      = ARG_ANYTHING,
2685 };
2686
2687 static unsigned long xdp_get_metalen(const struct xdp_buff *xdp)
2688 {
2689         return xdp_data_meta_unsupported(xdp) ? 0 :
2690                xdp->data - xdp->data_meta;
2691 }
2692
2693 BPF_CALL_2(bpf_xdp_adjust_head, struct xdp_buff *, xdp, int, offset)
2694 {
2695         void *xdp_frame_end = xdp->data_hard_start + sizeof(struct xdp_frame);
2696         unsigned long metalen = xdp_get_metalen(xdp);
2697         void *data_start = xdp->data_hard_start + metalen;
2698         void *data = xdp->data + offset;
2699
2700         if (unlikely(data < data_start ||
2701                      data > xdp->data_end - ETH_HLEN))
2702                 return -EINVAL;
2703
2704         /* Avoid info leak, when reusing area prev used by xdp_frame */
2705         if (data < xdp_frame_end) {
2706                 unsigned long clearlen = xdp_frame_end - data;
2707
2708                 memset(data, 0, clearlen);
2709         }
2710
2711         if (metalen)
2712                 memmove(xdp->data_meta + offset,
2713                         xdp->data_meta, metalen);
2714         xdp->data_meta += offset;
2715         xdp->data = data;
2716
2717         return 0;
2718 }
2719
2720 static const struct bpf_func_proto bpf_xdp_adjust_head_proto = {
2721         .func           = bpf_xdp_adjust_head,
2722         .gpl_only       = false,
2723         .ret_type       = RET_INTEGER,
2724         .arg1_type      = ARG_PTR_TO_CTX,
2725         .arg2_type      = ARG_ANYTHING,
2726 };
2727
2728 BPF_CALL_2(bpf_xdp_adjust_meta, struct xdp_buff *, xdp, int, offset)
2729 {
2730         void *meta = xdp->data_meta + offset;
2731         unsigned long metalen = xdp->data - meta;
2732
2733         if (xdp_data_meta_unsupported(xdp))
2734                 return -ENOTSUPP;
2735         if (unlikely(meta < xdp->data_hard_start ||
2736                      meta > xdp->data))
2737                 return -EINVAL;
2738         if (unlikely((metalen & (sizeof(__u32) - 1)) ||
2739                      (metalen > 32)))
2740                 return -EACCES;
2741
2742         xdp->data_meta = meta;
2743
2744         return 0;
2745 }
2746
2747 static const struct bpf_func_proto bpf_xdp_adjust_meta_proto = {
2748         .func           = bpf_xdp_adjust_meta,
2749         .gpl_only       = false,
2750         .ret_type       = RET_INTEGER,
2751         .arg1_type      = ARG_PTR_TO_CTX,
2752         .arg2_type      = ARG_ANYTHING,
2753 };
2754
2755 static int __bpf_tx_xdp(struct net_device *dev,
2756                         struct bpf_map *map,
2757                         struct xdp_buff *xdp,
2758                         u32 index)
2759 {
2760         struct xdp_frame *xdpf;
2761         int err;
2762
2763         if (!dev->netdev_ops->ndo_xdp_xmit) {
2764                 return -EOPNOTSUPP;
2765         }
2766
2767         xdpf = convert_to_xdp_frame(xdp);
2768         if (unlikely(!xdpf))
2769                 return -EOVERFLOW;
2770
2771         err = dev->netdev_ops->ndo_xdp_xmit(dev, xdpf);
2772         if (err)
2773                 return err;
2774         dev->netdev_ops->ndo_xdp_flush(dev);
2775         return 0;
2776 }
2777
2778 static int __bpf_tx_xdp_map(struct net_device *dev_rx, void *fwd,
2779                             struct bpf_map *map,
2780                             struct xdp_buff *xdp,
2781                             u32 index)
2782 {
2783         int err;
2784
2785         if (map->map_type == BPF_MAP_TYPE_DEVMAP) {
2786                 struct net_device *dev = fwd;
2787                 struct xdp_frame *xdpf;
2788
2789                 if (!dev->netdev_ops->ndo_xdp_xmit)
2790                         return -EOPNOTSUPP;
2791
2792                 xdpf = convert_to_xdp_frame(xdp);
2793                 if (unlikely(!xdpf))
2794                         return -EOVERFLOW;
2795
2796                 /* TODO: move to inside map code instead, for bulk support
2797                  * err = dev_map_enqueue(dev, xdp);
2798                  */
2799                 err = dev->netdev_ops->ndo_xdp_xmit(dev, xdpf);
2800                 if (err)
2801                         return err;
2802                 __dev_map_insert_ctx(map, index);
2803
2804         } else if (map->map_type == BPF_MAP_TYPE_CPUMAP) {
2805                 struct bpf_cpu_map_entry *rcpu = fwd;
2806
2807                 err = cpu_map_enqueue(rcpu, xdp, dev_rx);
2808                 if (err)
2809                         return err;
2810                 __cpu_map_insert_ctx(map, index);
2811         }
2812         return 0;
2813 }
2814
2815 void xdp_do_flush_map(void)
2816 {
2817         struct redirect_info *ri = this_cpu_ptr(&redirect_info);
2818         struct bpf_map *map = ri->map_to_flush;
2819
2820         ri->map_to_flush = NULL;
2821         if (map) {
2822                 switch (map->map_type) {
2823                 case BPF_MAP_TYPE_DEVMAP:
2824                         __dev_map_flush(map);
2825                         break;
2826                 case BPF_MAP_TYPE_CPUMAP:
2827                         __cpu_map_flush(map);
2828                         break;
2829                 default:
2830                         break;
2831                 }
2832         }
2833 }
2834 EXPORT_SYMBOL_GPL(xdp_do_flush_map);
2835
2836 static void *__xdp_map_lookup_elem(struct bpf_map *map, u32 index)
2837 {
2838         switch (map->map_type) {
2839         case BPF_MAP_TYPE_DEVMAP:
2840                 return __dev_map_lookup_elem(map, index);
2841         case BPF_MAP_TYPE_CPUMAP:
2842                 return __cpu_map_lookup_elem(map, index);
2843         default:
2844                 return NULL;
2845         }
2846 }
2847
2848 static inline bool xdp_map_invalid(const struct bpf_prog *xdp_prog,
2849                                    unsigned long aux)
2850 {
2851         return (unsigned long)xdp_prog->aux != aux;
2852 }
2853
2854 static int xdp_do_redirect_map(struct net_device *dev, struct xdp_buff *xdp,
2855                                struct bpf_prog *xdp_prog)
2856 {
2857         struct redirect_info *ri = this_cpu_ptr(&redirect_info);
2858         unsigned long map_owner = ri->map_owner;
2859         struct bpf_map *map = ri->map;
2860         u32 index = ri->ifindex;
2861         void *fwd = NULL;
2862         int err;
2863
2864         ri->ifindex = 0;
2865         ri->map = NULL;
2866         ri->map_owner = 0;
2867
2868         if (unlikely(xdp_map_invalid(xdp_prog, map_owner))) {
2869                 err = -EFAULT;
2870                 map = NULL;
2871                 goto err;
2872         }
2873
2874         fwd = __xdp_map_lookup_elem(map, index);
2875         if (!fwd) {
2876                 err = -EINVAL;
2877                 goto err;
2878         }
2879         if (ri->map_to_flush && ri->map_to_flush != map)
2880                 xdp_do_flush_map();
2881
2882         err = __bpf_tx_xdp_map(dev, fwd, map, xdp, index);
2883         if (unlikely(err))
2884                 goto err;
2885
2886         ri->map_to_flush = map;
2887         _trace_xdp_redirect_map(dev, xdp_prog, fwd, map, index);
2888         return 0;
2889 err:
2890         _trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map, index, err);
2891         return err;
2892 }
2893
2894 int xdp_do_redirect(struct net_device *dev, struct xdp_buff *xdp,
2895                     struct bpf_prog *xdp_prog)
2896 {
2897         struct redirect_info *ri = this_cpu_ptr(&redirect_info);
2898         struct net_device *fwd;
2899         u32 index = ri->ifindex;
2900         int err;
2901
2902         if (ri->map)
2903                 return xdp_do_redirect_map(dev, xdp, xdp_prog);
2904
2905         fwd = dev_get_by_index_rcu(dev_net(dev), index);
2906         ri->ifindex = 0;
2907         if (unlikely(!fwd)) {
2908                 err = -EINVAL;
2909                 goto err;
2910         }
2911
2912         err = __bpf_tx_xdp(fwd, NULL, xdp, 0);
2913         if (unlikely(err))
2914                 goto err;
2915
2916         _trace_xdp_redirect(dev, xdp_prog, index);
2917         return 0;
2918 err:
2919         _trace_xdp_redirect_err(dev, xdp_prog, index, err);
2920         return err;
2921 }
2922 EXPORT_SYMBOL_GPL(xdp_do_redirect);
2923
2924 static int __xdp_generic_ok_fwd_dev(struct sk_buff *skb, struct net_device *fwd)
2925 {
2926         unsigned int len;
2927
2928         if (unlikely(!(fwd->flags & IFF_UP)))
2929                 return -ENETDOWN;
2930
2931         len = fwd->mtu + fwd->hard_header_len + VLAN_HLEN;
2932         if (skb->len > len)
2933                 return -EMSGSIZE;
2934
2935         return 0;
2936 }
2937
2938 static int xdp_do_generic_redirect_map(struct net_device *dev,
2939                                        struct sk_buff *skb,
2940                                        struct bpf_prog *xdp_prog)
2941 {
2942         struct redirect_info *ri = this_cpu_ptr(&redirect_info);
2943         unsigned long map_owner = ri->map_owner;
2944         struct bpf_map *map = ri->map;
2945         struct net_device *fwd = NULL;
2946         u32 index = ri->ifindex;
2947         int err = 0;
2948
2949         ri->ifindex = 0;
2950         ri->map = NULL;
2951         ri->map_owner = 0;
2952
2953         if (unlikely(xdp_map_invalid(xdp_prog, map_owner))) {
2954                 err = -EFAULT;
2955                 map = NULL;
2956                 goto err;
2957         }
2958         fwd = __xdp_map_lookup_elem(map, index);
2959         if (unlikely(!fwd)) {
2960                 err = -EINVAL;
2961                 goto err;
2962         }
2963
2964         if (map->map_type == BPF_MAP_TYPE_DEVMAP) {
2965                 if (unlikely((err = __xdp_generic_ok_fwd_dev(skb, fwd))))
2966                         goto err;
2967                 skb->dev = fwd;
2968         } else {
2969                 /* TODO: Handle BPF_MAP_TYPE_CPUMAP */
2970                 err = -EBADRQC;
2971                 goto err;
2972         }
2973
2974         _trace_xdp_redirect_map(dev, xdp_prog, fwd, map, index);
2975         return 0;
2976 err:
2977         _trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map, index, err);
2978         return err;
2979 }
2980
2981 int xdp_do_generic_redirect(struct net_device *dev, struct sk_buff *skb,
2982                             struct bpf_prog *xdp_prog)
2983 {
2984         struct redirect_info *ri = this_cpu_ptr(&redirect_info);
2985         u32 index = ri->ifindex;
2986         struct net_device *fwd;
2987         int err = 0;
2988
2989         if (ri->map)
2990                 return xdp_do_generic_redirect_map(dev, skb, xdp_prog);
2991
2992         ri->ifindex = 0;
2993         fwd = dev_get_by_index_rcu(dev_net(dev), index);
2994         if (unlikely(!fwd)) {
2995                 err = -EINVAL;
2996                 goto err;
2997         }
2998
2999         if (unlikely((err = __xdp_generic_ok_fwd_dev(skb, fwd))))
3000                 goto err;
3001
3002         skb->dev = fwd;
3003         _trace_xdp_redirect(dev, xdp_prog, index);
3004         return 0;
3005 err:
3006         _trace_xdp_redirect_err(dev, xdp_prog, index, err);
3007         return err;
3008 }
3009 EXPORT_SYMBOL_GPL(xdp_do_generic_redirect);
3010
3011 BPF_CALL_2(bpf_xdp_redirect, u32, ifindex, u64, flags)
3012 {
3013         struct redirect_info *ri = this_cpu_ptr(&redirect_info);
3014
3015         if (unlikely(flags))
3016                 return XDP_ABORTED;
3017
3018         ri->ifindex = ifindex;
3019         ri->flags = flags;
3020         ri->map = NULL;
3021         ri->map_owner = 0;
3022
3023         return XDP_REDIRECT;
3024 }
3025
3026 static const struct bpf_func_proto bpf_xdp_redirect_proto = {
3027         .func           = bpf_xdp_redirect,
3028         .gpl_only       = false,
3029         .ret_type       = RET_INTEGER,
3030         .arg1_type      = ARG_ANYTHING,
3031         .arg2_type      = ARG_ANYTHING,
3032 };
3033
3034 BPF_CALL_4(bpf_xdp_redirect_map, struct bpf_map *, map, u32, ifindex, u64, flags,
3035            unsigned long, map_owner)
3036 {
3037         struct redirect_info *ri = this_cpu_ptr(&redirect_info);
3038
3039         if (unlikely(flags))
3040                 return XDP_ABORTED;
3041
3042         ri->ifindex = ifindex;
3043         ri->flags = flags;
3044         ri->map = map;
3045         ri->map_owner = map_owner;
3046
3047         return XDP_REDIRECT;
3048 }
3049
3050 /* Note, arg4 is hidden from users and populated by the verifier
3051  * with the right pointer.
3052  */
3053 static const struct bpf_func_proto bpf_xdp_redirect_map_proto = {
3054         .func           = bpf_xdp_redirect_map,
3055         .gpl_only       = false,
3056         .ret_type       = RET_INTEGER,
3057         .arg1_type      = ARG_CONST_MAP_PTR,
3058         .arg2_type      = ARG_ANYTHING,
3059         .arg3_type      = ARG_ANYTHING,
3060 };
3061
3062 bool bpf_helper_changes_pkt_data(void *func)
3063 {
3064         if (func == bpf_skb_vlan_push ||
3065             func == bpf_skb_vlan_pop ||
3066             func == bpf_skb_store_bytes ||
3067             func == bpf_skb_change_proto ||
3068             func == bpf_skb_change_head ||
3069             func == bpf_skb_change_tail ||
3070             func == bpf_skb_adjust_room ||
3071             func == bpf_skb_pull_data ||
3072             func == bpf_clone_redirect ||
3073             func == bpf_l3_csum_replace ||
3074             func == bpf_l4_csum_replace ||
3075             func == bpf_xdp_adjust_head ||
3076             func == bpf_xdp_adjust_meta ||
3077             func == bpf_msg_pull_data)
3078                 return true;
3079
3080         return false;
3081 }
3082
3083 static unsigned long bpf_skb_copy(void *dst_buff, const void *skb,
3084                                   unsigned long off, unsigned long len)
3085 {
3086         void *ptr = skb_header_pointer(skb, off, len, dst_buff);
3087
3088         if (unlikely(!ptr))
3089                 return len;
3090         if (ptr != dst_buff)
3091                 memcpy(dst_buff, ptr, len);
3092
3093         return 0;
3094 }
3095
3096 BPF_CALL_5(bpf_skb_event_output, struct sk_buff *, skb, struct bpf_map *, map,
3097            u64, flags, void *, meta, u64, meta_size)
3098 {
3099         u64 skb_size = (flags & BPF_F_CTXLEN_MASK) >> 32;
3100
3101         if (unlikely(flags & ~(BPF_F_CTXLEN_MASK | BPF_F_INDEX_MASK)))
3102                 return -EINVAL;
3103         if (unlikely(skb_size > skb->len))
3104                 return -EFAULT;
3105
3106         return bpf_event_output(map, flags, meta, meta_size, skb, skb_size,
3107                                 bpf_skb_copy);
3108 }
3109
3110 static const struct bpf_func_proto bpf_skb_event_output_proto = {
3111         .func           = bpf_skb_event_output,
3112         .gpl_only       = true,
3113         .ret_type       = RET_INTEGER,
3114         .arg1_type      = ARG_PTR_TO_CTX,
3115         .arg2_type      = ARG_CONST_MAP_PTR,
3116         .arg3_type      = ARG_ANYTHING,
3117         .arg4_type      = ARG_PTR_TO_MEM,
3118         .arg5_type      = ARG_CONST_SIZE_OR_ZERO,
3119 };
3120
3121 static unsigned short bpf_tunnel_key_af(u64 flags)
3122 {
3123         return flags & BPF_F_TUNINFO_IPV6 ? AF_INET6 : AF_INET;
3124 }
3125
3126 BPF_CALL_4(bpf_skb_get_tunnel_key, struct sk_buff *, skb, struct bpf_tunnel_key *, to,
3127            u32, size, u64, flags)
3128 {
3129         const struct ip_tunnel_info *info = skb_tunnel_info(skb);
3130         u8 compat[sizeof(struct bpf_tunnel_key)];
3131         void *to_orig = to;
3132         int err;
3133
3134         if (unlikely(!info || (flags & ~(BPF_F_TUNINFO_IPV6)))) {
3135                 err = -EINVAL;
3136                 goto err_clear;
3137         }
3138         if (ip_tunnel_info_af(info) != bpf_tunnel_key_af(flags)) {
3139                 err = -EPROTO;
3140                 goto err_clear;
3141         }
3142         if (unlikely(size != sizeof(struct bpf_tunnel_key))) {
3143                 err = -EINVAL;
3144                 switch (size) {
3145                 case offsetof(struct bpf_tunnel_key, tunnel_label):
3146                 case offsetof(struct bpf_tunnel_key, tunnel_ext):
3147                         goto set_compat;
3148                 case offsetof(struct bpf_tunnel_key, remote_ipv6[1]):
3149                         /* Fixup deprecated structure layouts here, so we have
3150                          * a common path later on.
3151                          */
3152                         if (ip_tunnel_info_af(info) != AF_INET)
3153                                 goto err_clear;
3154 set_compat:
3155                         to = (struct bpf_tunnel_key *)compat;
3156                         break;
3157                 default:
3158                         goto err_clear;
3159                 }
3160         }
3161
3162         to->tunnel_id = be64_to_cpu(info->key.tun_id);
3163         to->tunnel_tos = info->key.tos;
3164         to->tunnel_ttl = info->key.ttl;
3165
3166         if (flags & BPF_F_TUNINFO_IPV6) {
3167                 memcpy(to->remote_ipv6, &info->key.u.ipv6.src,
3168                        sizeof(to->remote_ipv6));
3169                 to->tunnel_label = be32_to_cpu(info->key.label);
3170         } else {
3171                 to->remote_ipv4 = be32_to_cpu(info->key.u.ipv4.src);
3172         }
3173
3174         if (unlikely(size != sizeof(struct bpf_tunnel_key)))
3175                 memcpy(to_orig, to, size);
3176
3177         return 0;
3178 err_clear:
3179         memset(to_orig, 0, size);
3180         return err;
3181 }
3182
3183 static const struct bpf_func_proto bpf_skb_get_tunnel_key_proto = {
3184         .func           = bpf_skb_get_tunnel_key,
3185         .gpl_only       = false,
3186         .ret_type       = RET_INTEGER,
3187         .arg1_type      = ARG_PTR_TO_CTX,
3188         .arg2_type      = ARG_PTR_TO_UNINIT_MEM,
3189         .arg3_type      = ARG_CONST_SIZE,
3190         .arg4_type      = ARG_ANYTHING,
3191 };
3192
3193 BPF_CALL_3(bpf_skb_get_tunnel_opt, struct sk_buff *, skb, u8 *, to, u32, size)
3194 {
3195         const struct ip_tunnel_info *info = skb_tunnel_info(skb);
3196         int err;
3197
3198         if (unlikely(!info ||
3199                      !(info->key.tun_flags & TUNNEL_OPTIONS_PRESENT))) {
3200                 err = -ENOENT;
3201                 goto err_clear;
3202         }
3203         if (unlikely(size < info->options_len)) {
3204                 err = -ENOMEM;
3205                 goto err_clear;
3206         }
3207
3208         ip_tunnel_info_opts_get(to, info);
3209         if (size > info->options_len)
3210                 memset(to + info->options_len, 0, size - info->options_len);
3211
3212         return info->options_len;
3213 err_clear:
3214         memset(to, 0, size);
3215         return err;
3216 }
3217
3218 static const struct bpf_func_proto bpf_skb_get_tunnel_opt_proto = {
3219         .func           = bpf_skb_get_tunnel_opt,
3220         .gpl_only       = false,
3221         .ret_type       = RET_INTEGER,
3222         .arg1_type      = ARG_PTR_TO_CTX,
3223         .arg2_type      = ARG_PTR_TO_UNINIT_MEM,
3224         .arg3_type      = ARG_CONST_SIZE,
3225 };
3226
3227 static struct metadata_dst __percpu *md_dst;
3228
3229 BPF_CALL_4(bpf_skb_set_tunnel_key, struct sk_buff *, skb,
3230            const struct bpf_tunnel_key *, from, u32, size, u64, flags)
3231 {
3232         struct metadata_dst *md = this_cpu_ptr(md_dst);
3233         u8 compat[sizeof(struct bpf_tunnel_key)];
3234         struct ip_tunnel_info *info;
3235
3236         if (unlikely(flags & ~(BPF_F_TUNINFO_IPV6 | BPF_F_ZERO_CSUM_TX |
3237                                BPF_F_DONT_FRAGMENT | BPF_F_SEQ_NUMBER)))
3238                 return -EINVAL;
3239         if (unlikely(size != sizeof(struct bpf_tunnel_key))) {
3240                 switch (size) {
3241                 case offsetof(struct bpf_tunnel_key, tunnel_label):
3242                 case offsetof(struct bpf_tunnel_key, tunnel_ext):
3243                 case offsetof(struct bpf_tunnel_key, remote_ipv6[1]):
3244                         /* Fixup deprecated structure layouts here, so we have
3245                          * a common path later on.
3246                          */
3247                         memcpy(compat, from, size);
3248                         memset(compat + size, 0, sizeof(compat) - size);
3249                         from = (const struct bpf_tunnel_key *) compat;
3250                         break;
3251                 default:
3252                         return -EINVAL;
3253                 }
3254         }
3255         if (unlikely((!(flags & BPF_F_TUNINFO_IPV6) && from->tunnel_label) ||
3256                      from->tunnel_ext))
3257                 return -EINVAL;
3258
3259         skb_dst_drop(skb);
3260         dst_hold((struct dst_entry *) md);
3261         skb_dst_set(skb, (struct dst_entry *) md);
3262
3263         info = &md->u.tun_info;
3264         info->mode = IP_TUNNEL_INFO_TX;
3265
3266         info->key.tun_flags = TUNNEL_KEY | TUNNEL_CSUM | TUNNEL_NOCACHE;
3267         if (flags & BPF_F_DONT_FRAGMENT)
3268                 info->key.tun_flags |= TUNNEL_DONT_FRAGMENT;
3269         if (flags & BPF_F_ZERO_CSUM_TX)
3270                 info->key.tun_flags &= ~TUNNEL_CSUM;
3271         if (flags & BPF_F_SEQ_NUMBER)
3272                 info->key.tun_flags |= TUNNEL_SEQ;
3273
3274         info->key.tun_id = cpu_to_be64(from->tunnel_id);
3275         info->key.tos = from->tunnel_tos;
3276         info->key.ttl = from->tunnel_ttl;
3277
3278         if (flags & BPF_F_TUNINFO_IPV6) {
3279                 info->mode |= IP_TUNNEL_INFO_IPV6;
3280                 memcpy(&info->key.u.ipv6.dst, from->remote_ipv6,
3281                        sizeof(from->remote_ipv6));
3282                 info->key.label = cpu_to_be32(from->tunnel_label) &
3283                                   IPV6_FLOWLABEL_MASK;
3284         } else {
3285                 info->key.u.ipv4.dst = cpu_to_be32(from->remote_ipv4);
3286         }
3287
3288         return 0;
3289 }
3290
3291 static const struct bpf_func_proto bpf_skb_set_tunnel_key_proto = {
3292         .func           = bpf_skb_set_tunnel_key,
3293         .gpl_only       = false,
3294         .ret_type       = RET_INTEGER,
3295         .arg1_type      = ARG_PTR_TO_CTX,
3296         .arg2_type      = ARG_PTR_TO_MEM,
3297         .arg3_type      = ARG_CONST_SIZE,
3298         .arg4_type      = ARG_ANYTHING,
3299 };
3300
3301 BPF_CALL_3(bpf_skb_set_tunnel_opt, struct sk_buff *, skb,
3302            const u8 *, from, u32, size)
3303 {
3304         struct ip_tunnel_info *info = skb_tunnel_info(skb);
3305         const struct metadata_dst *md = this_cpu_ptr(md_dst);
3306
3307         if (unlikely(info != &md->u.tun_info || (size & (sizeof(u32) - 1))))
3308                 return -EINVAL;
3309         if (unlikely(size > IP_TUNNEL_OPTS_MAX))
3310                 return -ENOMEM;
3311
3312         ip_tunnel_info_opts_set(info, from, size);
3313
3314         return 0;
3315 }
3316
3317 static const struct bpf_func_proto bpf_skb_set_tunnel_opt_proto = {
3318         .func           = bpf_skb_set_tunnel_opt,
3319         .gpl_only       = false,
3320         .ret_type       = RET_INTEGER,
3321         .arg1_type      = ARG_PTR_TO_CTX,
3322         .arg2_type      = ARG_PTR_TO_MEM,
3323         .arg3_type      = ARG_CONST_SIZE,
3324 };
3325
3326 static const struct bpf_func_proto *
3327 bpf_get_skb_set_tunnel_proto(enum bpf_func_id which)
3328 {
3329         if (!md_dst) {
3330                 struct metadata_dst __percpu *tmp;
3331
3332                 tmp = metadata_dst_alloc_percpu(IP_TUNNEL_OPTS_MAX,
3333                                                 METADATA_IP_TUNNEL,
3334                                                 GFP_KERNEL);
3335                 if (!tmp)
3336                         return NULL;
3337                 if (cmpxchg(&md_dst, NULL, tmp))
3338                         metadata_dst_free_percpu(tmp);
3339         }
3340
3341         switch (which) {
3342         case BPF_FUNC_skb_set_tunnel_key:
3343                 return &bpf_skb_set_tunnel_key_proto;
3344         case BPF_FUNC_skb_set_tunnel_opt:
3345                 return &bpf_skb_set_tunnel_opt_proto;
3346         default:
3347                 return NULL;
3348         }
3349 }
3350
3351 BPF_CALL_3(bpf_skb_under_cgroup, struct sk_buff *, skb, struct bpf_map *, map,
3352            u32, idx)
3353 {
3354         struct bpf_array *array = container_of(map, struct bpf_array, map);
3355         struct cgroup *cgrp;
3356         struct sock *sk;
3357
3358         sk = skb_to_full_sk(skb);
3359         if (!sk || !sk_fullsock(sk))
3360                 return -ENOENT;
3361         if (unlikely(idx >= array->map.max_entries))
3362                 return -E2BIG;
3363
3364         cgrp = READ_ONCE(array->ptrs[idx]);
3365         if (unlikely(!cgrp))
3366                 return -EAGAIN;
3367
3368         return sk_under_cgroup_hierarchy(sk, cgrp);
3369 }
3370
3371 static const struct bpf_func_proto bpf_skb_under_cgroup_proto = {
3372         .func           = bpf_skb_under_cgroup,
3373         .gpl_only       = false,
3374         .ret_type       = RET_INTEGER,
3375         .arg1_type      = ARG_PTR_TO_CTX,
3376         .arg2_type      = ARG_CONST_MAP_PTR,
3377         .arg3_type      = ARG_ANYTHING,
3378 };
3379
3380 static unsigned long bpf_xdp_copy(void *dst_buff, const void *src_buff,
3381                                   unsigned long off, unsigned long len)
3382 {
3383         memcpy(dst_buff, src_buff + off, len);
3384         return 0;
3385 }
3386
3387 BPF_CALL_5(bpf_xdp_event_output, struct xdp_buff *, xdp, struct bpf_map *, map,
3388            u64, flags, void *, meta, u64, meta_size)
3389 {
3390         u64 xdp_size = (flags & BPF_F_CTXLEN_MASK) >> 32;
3391
3392         if (unlikely(flags & ~(BPF_F_CTXLEN_MASK | BPF_F_INDEX_MASK)))
3393                 return -EINVAL;
3394         if (unlikely(xdp_size > (unsigned long)(xdp->data_end - xdp->data)))
3395                 return -EFAULT;
3396
3397         return bpf_event_output(map, flags, meta, meta_size, xdp->data,
3398                                 xdp_size, bpf_xdp_copy);
3399 }
3400
3401 static const struct bpf_func_proto bpf_xdp_event_output_proto = {
3402         .func           = bpf_xdp_event_output,
3403         .gpl_only       = true,
3404         .ret_type       = RET_INTEGER,
3405         .arg1_type      = ARG_PTR_TO_CTX,
3406         .arg2_type      = ARG_CONST_MAP_PTR,
3407         .arg3_type      = ARG_ANYTHING,
3408         .arg4_type      = ARG_PTR_TO_MEM,
3409         .arg5_type      = ARG_CONST_SIZE_OR_ZERO,
3410 };
3411
3412 BPF_CALL_1(bpf_get_socket_cookie, struct sk_buff *, skb)
3413 {
3414         return skb->sk ? sock_gen_cookie(skb->sk) : 0;
3415 }
3416
3417 static const struct bpf_func_proto bpf_get_socket_cookie_proto = {
3418         .func           = bpf_get_socket_cookie,
3419         .gpl_only       = false,
3420         .ret_type       = RET_INTEGER,
3421         .arg1_type      = ARG_PTR_TO_CTX,
3422 };
3423
3424 BPF_CALL_1(bpf_get_socket_uid, struct sk_buff *, skb)
3425 {
3426         struct sock *sk = sk_to_full_sk(skb->sk);
3427         kuid_t kuid;
3428
3429         if (!sk || !sk_fullsock(sk))
3430                 return overflowuid;
3431         kuid = sock_net_uid(sock_net(sk), sk);
3432         return from_kuid_munged(sock_net(sk)->user_ns, kuid);
3433 }
3434
3435 static const struct bpf_func_proto bpf_get_socket_uid_proto = {
3436         .func           = bpf_get_socket_uid,
3437         .gpl_only       = false,
3438         .ret_type       = RET_INTEGER,
3439         .arg1_type      = ARG_PTR_TO_CTX,
3440 };
3441
3442 BPF_CALL_5(bpf_setsockopt, struct bpf_sock_ops_kern *, bpf_sock,
3443            int, level, int, optname, char *, optval, int, optlen)
3444 {
3445         struct sock *sk = bpf_sock->sk;
3446         int ret = 0;
3447         int val;
3448
3449         if (!sk_fullsock(sk))
3450                 return -EINVAL;
3451
3452         if (level == SOL_SOCKET) {
3453                 if (optlen != sizeof(int))
3454                         return -EINVAL;
3455                 val = *((int *)optval);
3456
3457                 /* Only some socketops are supported */
3458                 switch (optname) {
3459                 case SO_RCVBUF:
3460                         sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
3461                         sk->sk_rcvbuf = max_t(int, val * 2, SOCK_MIN_RCVBUF);
3462                         break;
3463                 case SO_SNDBUF:
3464                         sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
3465                         sk->sk_sndbuf = max_t(int, val * 2, SOCK_MIN_SNDBUF);
3466                         break;
3467                 case SO_MAX_PACING_RATE:
3468                         sk->sk_max_pacing_rate = val;
3469                         sk->sk_pacing_rate = min(sk->sk_pacing_rate,
3470                                                  sk->sk_max_pacing_rate);
3471                         break;
3472                 case SO_PRIORITY:
3473                         sk->sk_priority = val;
3474                         break;
3475                 case SO_RCVLOWAT:
3476                         if (val < 0)
3477                                 val = INT_MAX;
3478                         sk->sk_rcvlowat = val ? : 1;
3479                         break;
3480                 case SO_MARK:
3481                         sk->sk_mark = val;
3482                         break;
3483                 default:
3484                         ret = -EINVAL;
3485                 }
3486 #ifdef CONFIG_INET
3487         } else if (level == SOL_IP) {
3488                 if (optlen != sizeof(int) || sk->sk_family != AF_INET)
3489                         return -EINVAL;
3490
3491                 val = *((int *)optval);
3492                 /* Only some options are supported */
3493                 switch (optname) {
3494                 case IP_TOS:
3495                         if (val < -1 || val > 0xff) {
3496                                 ret = -EINVAL;
3497                         } else {
3498                                 struct inet_sock *inet = inet_sk(sk);
3499
3500                                 if (val == -1)
3501                                         val = 0;
3502                                 inet->tos = val;
3503                         }
3504                         break;
3505                 default:
3506                         ret = -EINVAL;
3507                 }
3508 #if IS_ENABLED(CONFIG_IPV6)
3509         } else if (level == SOL_IPV6) {
3510                 if (optlen != sizeof(int) || sk->sk_family != AF_INET6)
3511                         return -EINVAL;
3512
3513                 val = *((int *)optval);
3514                 /* Only some options are supported */
3515                 switch (optname) {
3516                 case IPV6_TCLASS:
3517                         if (val < -1 || val > 0xff) {
3518                                 ret = -EINVAL;
3519                         } else {
3520                                 struct ipv6_pinfo *np = inet6_sk(sk);
3521
3522                                 if (val == -1)
3523                                         val = 0;
3524                                 np->tclass = val;
3525                         }
3526                         break;
3527                 default:
3528                         ret = -EINVAL;
3529                 }
3530 #endif
3531         } else if (level == SOL_TCP &&
3532                    sk->sk_prot->setsockopt == tcp_setsockopt) {
3533                 if (optname == TCP_CONGESTION) {
3534                         char name[TCP_CA_NAME_MAX];
3535                         bool reinit = bpf_sock->op > BPF_SOCK_OPS_NEEDS_ECN;
3536
3537                         strncpy(name, optval, min_t(long, optlen,
3538                                                     TCP_CA_NAME_MAX-1));
3539                         name[TCP_CA_NAME_MAX-1] = 0;
3540                         ret = tcp_set_congestion_control(sk, name, false,
3541                                                          reinit);
3542                 } else {
3543                         struct tcp_sock *tp = tcp_sk(sk);
3544
3545                         if (optlen != sizeof(int))
3546                                 return -EINVAL;
3547
3548                         val = *((int *)optval);
3549                         /* Only some options are supported */
3550                         switch (optname) {
3551                         case TCP_BPF_IW:
3552                                 if (val <= 0 || tp->data_segs_out > 0)
3553                                         ret = -EINVAL;
3554                                 else
3555                                         tp->snd_cwnd = val;
3556                                 break;
3557                         case TCP_BPF_SNDCWND_CLAMP:
3558                                 if (val <= 0) {
3559                                         ret = -EINVAL;
3560                                 } else {
3561                                         tp->snd_cwnd_clamp = val;
3562                                         tp->snd_ssthresh = val;
3563                                 }
3564                                 break;
3565                         default:
3566                                 ret = -EINVAL;
3567                         }
3568                 }
3569 #endif
3570         } else {
3571                 ret = -EINVAL;
3572         }
3573         return ret;
3574 }
3575
3576 static const struct bpf_func_proto bpf_setsockopt_proto = {
3577         .func           = bpf_setsockopt,
3578         .gpl_only       = false,
3579         .ret_type       = RET_INTEGER,
3580         .arg1_type      = ARG_PTR_TO_CTX,
3581         .arg2_type      = ARG_ANYTHING,
3582         .arg3_type      = ARG_ANYTHING,
3583         .arg4_type      = ARG_PTR_TO_MEM,
3584         .arg5_type      = ARG_CONST_SIZE,
3585 };
3586
3587 BPF_CALL_5(bpf_getsockopt, struct bpf_sock_ops_kern *, bpf_sock,
3588            int, level, int, optname, char *, optval, int, optlen)
3589 {
3590         struct sock *sk = bpf_sock->sk;
3591
3592         if (!sk_fullsock(sk))
3593                 goto err_clear;
3594
3595 #ifdef CONFIG_INET
3596         if (level == SOL_TCP && sk->sk_prot->getsockopt == tcp_getsockopt) {
3597                 if (optname == TCP_CONGESTION) {
3598                         struct inet_connection_sock *icsk = inet_csk(sk);
3599
3600                         if (!icsk->icsk_ca_ops || optlen <= 1)
3601                                 goto err_clear;
3602                         strncpy(optval, icsk->icsk_ca_ops->name, optlen);
3603                         optval[optlen - 1] = 0;
3604                 } else {
3605                         goto err_clear;
3606                 }
3607         } else if (level == SOL_IP) {
3608                 struct inet_sock *inet = inet_sk(sk);
3609
3610                 if (optlen != sizeof(int) || sk->sk_family != AF_INET)
3611                         goto err_clear;
3612
3613                 /* Only some options are supported */
3614                 switch (optname) {
3615                 case IP_TOS:
3616                         *((int *)optval) = (int)inet->tos;
3617                         break;
3618                 default:
3619                         goto err_clear;
3620                 }
3621 #if IS_ENABLED(CONFIG_IPV6)
3622         } else if (level == SOL_IPV6) {
3623                 struct ipv6_pinfo *np = inet6_sk(sk);
3624
3625                 if (optlen != sizeof(int) || sk->sk_family != AF_INET6)
3626                         goto err_clear;
3627
3628                 /* Only some options are supported */
3629                 switch (optname) {
3630                 case IPV6_TCLASS:
3631                         *((int *)optval) = (int)np->tclass;
3632                         break;
3633                 default:
3634                         goto err_clear;
3635                 }
3636 #endif
3637         } else {
3638                 goto err_clear;
3639         }
3640         return 0;
3641 #endif
3642 err_clear:
3643         memset(optval, 0, optlen);
3644         return -EINVAL;
3645 }
3646
3647 static const struct bpf_func_proto bpf_getsockopt_proto = {
3648         .func           = bpf_getsockopt,
3649         .gpl_only       = false,
3650         .ret_type       = RET_INTEGER,
3651         .arg1_type      = ARG_PTR_TO_CTX,
3652         .arg2_type      = ARG_ANYTHING,
3653         .arg3_type      = ARG_ANYTHING,
3654         .arg4_type      = ARG_PTR_TO_UNINIT_MEM,
3655         .arg5_type      = ARG_CONST_SIZE,
3656 };
3657
3658 BPF_CALL_2(bpf_sock_ops_cb_flags_set, struct bpf_sock_ops_kern *, bpf_sock,
3659            int, argval)
3660 {
3661         struct sock *sk = bpf_sock->sk;
3662         int val = argval & BPF_SOCK_OPS_ALL_CB_FLAGS;
3663
3664         if (!IS_ENABLED(CONFIG_INET) || !sk_fullsock(sk))
3665                 return -EINVAL;
3666
3667         if (val)
3668                 tcp_sk(sk)->bpf_sock_ops_cb_flags = val;
3669
3670         return argval & (~BPF_SOCK_OPS_ALL_CB_FLAGS);
3671 }
3672
3673 static const struct bpf_func_proto bpf_sock_ops_cb_flags_set_proto = {
3674         .func           = bpf_sock_ops_cb_flags_set,
3675         .gpl_only       = false,
3676         .ret_type       = RET_INTEGER,
3677         .arg1_type      = ARG_PTR_TO_CTX,
3678         .arg2_type      = ARG_ANYTHING,
3679 };
3680
3681 const struct ipv6_bpf_stub *ipv6_bpf_stub __read_mostly;
3682 EXPORT_SYMBOL_GPL(ipv6_bpf_stub);
3683
3684 BPF_CALL_3(bpf_bind, struct bpf_sock_addr_kern *, ctx, struct sockaddr *, addr,
3685            int, addr_len)
3686 {
3687 #ifdef CONFIG_INET
3688         struct sock *sk = ctx->sk;
3689         int err;
3690
3691         /* Binding to port can be expensive so it's prohibited in the helper.
3692          * Only binding to IP is supported.
3693          */
3694         err = -EINVAL;
3695         if (addr->sa_family == AF_INET) {
3696                 if (addr_len < sizeof(struct sockaddr_in))
3697                         return err;
3698                 if (((struct sockaddr_in *)addr)->sin_port != htons(0))
3699                         return err;
3700                 return __inet_bind(sk, addr, addr_len, true, false);
3701 #if IS_ENABLED(CONFIG_IPV6)
3702         } else if (addr->sa_family == AF_INET6) {
3703                 if (addr_len < SIN6_LEN_RFC2133)
3704                         return err;
3705                 if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
3706                         return err;
3707                 /* ipv6_bpf_stub cannot be NULL, since it's called from
3708                  * bpf_cgroup_inet6_connect hook and ipv6 is already loaded
3709                  */
3710                 return ipv6_bpf_stub->inet6_bind(sk, addr, addr_len, true, false);
3711 #endif /* CONFIG_IPV6 */
3712         }
3713 #endif /* CONFIG_INET */
3714
3715         return -EAFNOSUPPORT;
3716 }
3717
3718 static const struct bpf_func_proto bpf_bind_proto = {
3719         .func           = bpf_bind,
3720         .gpl_only       = false,
3721         .ret_type       = RET_INTEGER,
3722         .arg1_type      = ARG_PTR_TO_CTX,
3723         .arg2_type      = ARG_PTR_TO_MEM,
3724         .arg3_type      = ARG_CONST_SIZE,
3725 };
3726
3727 static const struct bpf_func_proto *
3728 bpf_base_func_proto(enum bpf_func_id func_id)
3729 {
3730         switch (func_id) {
3731         case BPF_FUNC_map_lookup_elem:
3732                 return &bpf_map_lookup_elem_proto;
3733         case BPF_FUNC_map_update_elem:
3734                 return &bpf_map_update_elem_proto;
3735         case BPF_FUNC_map_delete_elem:
3736                 return &bpf_map_delete_elem_proto;
3737         case BPF_FUNC_get_prandom_u32:
3738                 return &bpf_get_prandom_u32_proto;
3739         case BPF_FUNC_get_smp_processor_id:
3740                 return &bpf_get_raw_smp_processor_id_proto;
3741         case BPF_FUNC_get_numa_node_id:
3742                 return &bpf_get_numa_node_id_proto;
3743         case BPF_FUNC_tail_call:
3744                 return &bpf_tail_call_proto;
3745         case BPF_FUNC_ktime_get_ns:
3746                 return &bpf_ktime_get_ns_proto;
3747         case BPF_FUNC_trace_printk:
3748                 if (capable(CAP_SYS_ADMIN))
3749                         return bpf_get_trace_printk_proto();
3750         default:
3751                 return NULL;
3752         }
3753 }
3754
3755 static const struct bpf_func_proto *
3756 sock_filter_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
3757 {
3758         switch (func_id) {
3759         /* inet and inet6 sockets are created in a process
3760          * context so there is always a valid uid/gid
3761          */
3762         case BPF_FUNC_get_current_uid_gid:
3763                 return &bpf_get_current_uid_gid_proto;
3764         default:
3765                 return bpf_base_func_proto(func_id);
3766         }
3767 }
3768
3769 static const struct bpf_func_proto *
3770 sock_addr_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
3771 {
3772         switch (func_id) {
3773         /* inet and inet6 sockets are created in a process
3774          * context so there is always a valid uid/gid
3775          */
3776         case BPF_FUNC_get_current_uid_gid:
3777                 return &bpf_get_current_uid_gid_proto;
3778         case BPF_FUNC_bind:
3779                 switch (prog->expected_attach_type) {
3780                 case BPF_CGROUP_INET4_CONNECT:
3781                 case BPF_CGROUP_INET6_CONNECT:
3782                         return &bpf_bind_proto;
3783                 default:
3784                         return NULL;
3785                 }
3786         default:
3787                 return bpf_base_func_proto(func_id);
3788         }
3789 }
3790
3791 static const struct bpf_func_proto *
3792 sk_filter_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
3793 {
3794         switch (func_id) {
3795         case BPF_FUNC_skb_load_bytes:
3796                 return &bpf_skb_load_bytes_proto;
3797         case BPF_FUNC_get_socket_cookie:
3798                 return &bpf_get_socket_cookie_proto;
3799         case BPF_FUNC_get_socket_uid:
3800                 return &bpf_get_socket_uid_proto;
3801         default:
3802                 return bpf_base_func_proto(func_id);
3803         }
3804 }
3805
3806 static const struct bpf_func_proto *
3807 tc_cls_act_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
3808 {
3809         switch (func_id) {
3810         case BPF_FUNC_skb_store_bytes:
3811                 return &bpf_skb_store_bytes_proto;
3812         case BPF_FUNC_skb_load_bytes:
3813                 return &bpf_skb_load_bytes_proto;
3814         case BPF_FUNC_skb_pull_data:
3815                 return &bpf_skb_pull_data_proto;
3816         case BPF_FUNC_csum_diff:
3817                 return &bpf_csum_diff_proto;
3818         case BPF_FUNC_csum_update:
3819                 return &bpf_csum_update_proto;
3820         case BPF_FUNC_l3_csum_replace:
3821                 return &bpf_l3_csum_replace_proto;
3822         case BPF_FUNC_l4_csum_replace:
3823                 return &bpf_l4_csum_replace_proto;
3824         case BPF_FUNC_clone_redirect:
3825                 return &bpf_clone_redirect_proto;
3826         case BPF_FUNC_get_cgroup_classid:
3827                 return &bpf_get_cgroup_classid_proto;
3828         case BPF_FUNC_skb_vlan_push:
3829                 return &bpf_skb_vlan_push_proto;
3830         case BPF_FUNC_skb_vlan_pop:
3831                 return &bpf_skb_vlan_pop_proto;
3832         case BPF_FUNC_skb_change_proto:
3833                 return &bpf_skb_change_proto_proto;
3834         case BPF_FUNC_skb_change_type:
3835                 return &bpf_skb_change_type_proto;
3836         case BPF_FUNC_skb_adjust_room:
3837                 return &bpf_skb_adjust_room_proto;
3838         case BPF_FUNC_skb_change_tail:
3839                 return &bpf_skb_change_tail_proto;
3840         case BPF_FUNC_skb_get_tunnel_key:
3841                 return &bpf_skb_get_tunnel_key_proto;
3842         case BPF_FUNC_skb_set_tunnel_key:
3843                 return bpf_get_skb_set_tunnel_proto(func_id);
3844         case BPF_FUNC_skb_get_tunnel_opt:
3845                 return &bpf_skb_get_tunnel_opt_proto;
3846         case BPF_FUNC_skb_set_tunnel_opt:
3847                 return bpf_get_skb_set_tunnel_proto(func_id);
3848         case BPF_FUNC_redirect:
3849                 return &bpf_redirect_proto;
3850         case BPF_FUNC_get_route_realm:
3851                 return &bpf_get_route_realm_proto;
3852         case BPF_FUNC_get_hash_recalc:
3853                 return &bpf_get_hash_recalc_proto;
3854         case BPF_FUNC_set_hash_invalid:
3855                 return &bpf_set_hash_invalid_proto;
3856         case BPF_FUNC_set_hash:
3857                 return &bpf_set_hash_proto;
3858         case BPF_FUNC_perf_event_output:
3859                 return &bpf_skb_event_output_proto;
3860         case BPF_FUNC_get_smp_processor_id:
3861                 return &bpf_get_smp_processor_id_proto;
3862         case BPF_FUNC_skb_under_cgroup:
3863                 return &bpf_skb_under_cgroup_proto;
3864         case BPF_FUNC_get_socket_cookie:
3865                 return &bpf_get_socket_cookie_proto;
3866         case BPF_FUNC_get_socket_uid:
3867                 return &bpf_get_socket_uid_proto;
3868         default:
3869                 return bpf_base_func_proto(func_id);
3870         }
3871 }
3872
3873 static const struct bpf_func_proto *
3874 xdp_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
3875 {
3876         switch (func_id) {
3877         case BPF_FUNC_perf_event_output:
3878                 return &bpf_xdp_event_output_proto;
3879         case BPF_FUNC_get_smp_processor_id:
3880                 return &bpf_get_smp_processor_id_proto;
3881         case BPF_FUNC_csum_diff:
3882                 return &bpf_csum_diff_proto;
3883         case BPF_FUNC_xdp_adjust_head:
3884                 return &bpf_xdp_adjust_head_proto;
3885         case BPF_FUNC_xdp_adjust_meta:
3886                 return &bpf_xdp_adjust_meta_proto;
3887         case BPF_FUNC_redirect:
3888                 return &bpf_xdp_redirect_proto;
3889         case BPF_FUNC_redirect_map:
3890                 return &bpf_xdp_redirect_map_proto;
3891         default:
3892                 return bpf_base_func_proto(func_id);
3893         }
3894 }
3895
3896 static const struct bpf_func_proto *
3897 lwt_inout_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
3898 {
3899         switch (func_id) {
3900         case BPF_FUNC_skb_load_bytes:
3901                 return &bpf_skb_load_bytes_proto;
3902         case BPF_FUNC_skb_pull_data:
3903                 return &bpf_skb_pull_data_proto;
3904         case BPF_FUNC_csum_diff:
3905                 return &bpf_csum_diff_proto;
3906         case BPF_FUNC_get_cgroup_classid:
3907                 return &bpf_get_cgroup_classid_proto;
3908         case BPF_FUNC_get_route_realm:
3909                 return &bpf_get_route_realm_proto;
3910         case BPF_FUNC_get_hash_recalc:
3911                 return &bpf_get_hash_recalc_proto;
3912         case BPF_FUNC_perf_event_output:
3913                 return &bpf_skb_event_output_proto;
3914         case BPF_FUNC_get_smp_processor_id:
3915                 return &bpf_get_smp_processor_id_proto;
3916         case BPF_FUNC_skb_under_cgroup:
3917                 return &bpf_skb_under_cgroup_proto;
3918         default:
3919                 return bpf_base_func_proto(func_id);
3920         }
3921 }
3922
3923 static const struct bpf_func_proto *
3924 sock_ops_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
3925 {
3926         switch (func_id) {
3927         case BPF_FUNC_setsockopt:
3928                 return &bpf_setsockopt_proto;
3929         case BPF_FUNC_getsockopt:
3930                 return &bpf_getsockopt_proto;
3931         case BPF_FUNC_sock_ops_cb_flags_set:
3932                 return &bpf_sock_ops_cb_flags_set_proto;
3933         case BPF_FUNC_sock_map_update:
3934                 return &bpf_sock_map_update_proto;
3935         default:
3936                 return bpf_base_func_proto(func_id);
3937         }
3938 }
3939
3940 static const struct bpf_func_proto *
3941 sk_msg_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
3942 {
3943         switch (func_id) {
3944         case BPF_FUNC_msg_redirect_map:
3945                 return &bpf_msg_redirect_map_proto;
3946         case BPF_FUNC_msg_apply_bytes:
3947                 return &bpf_msg_apply_bytes_proto;
3948         case BPF_FUNC_msg_cork_bytes:
3949                 return &bpf_msg_cork_bytes_proto;
3950         case BPF_FUNC_msg_pull_data:
3951                 return &bpf_msg_pull_data_proto;
3952         default:
3953                 return bpf_base_func_proto(func_id);
3954         }
3955 }
3956
3957 static const struct bpf_func_proto *
3958 sk_skb_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
3959 {
3960         switch (func_id) {
3961         case BPF_FUNC_skb_store_bytes:
3962                 return &bpf_skb_store_bytes_proto;
3963         case BPF_FUNC_skb_load_bytes:
3964                 return &bpf_skb_load_bytes_proto;
3965         case BPF_FUNC_skb_pull_data:
3966                 return &bpf_skb_pull_data_proto;
3967         case BPF_FUNC_skb_change_tail:
3968                 return &bpf_skb_change_tail_proto;
3969         case BPF_FUNC_skb_change_head:
3970                 return &bpf_skb_change_head_proto;
3971         case BPF_FUNC_get_socket_cookie:
3972                 return &bpf_get_socket_cookie_proto;
3973         case BPF_FUNC_get_socket_uid:
3974                 return &bpf_get_socket_uid_proto;
3975         case BPF_FUNC_sk_redirect_map:
3976                 return &bpf_sk_redirect_map_proto;
3977         default:
3978                 return bpf_base_func_proto(func_id);
3979         }
3980 }
3981
3982 static const struct bpf_func_proto *
3983 lwt_xmit_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
3984 {
3985         switch (func_id) {
3986         case BPF_FUNC_skb_get_tunnel_key:
3987                 return &bpf_skb_get_tunnel_key_proto;
3988         case BPF_FUNC_skb_set_tunnel_key:
3989                 return bpf_get_skb_set_tunnel_proto(func_id);
3990         case BPF_FUNC_skb_get_tunnel_opt:
3991                 return &bpf_skb_get_tunnel_opt_proto;
3992         case BPF_FUNC_skb_set_tunnel_opt:
3993                 return bpf_get_skb_set_tunnel_proto(func_id);
3994         case BPF_FUNC_redirect:
3995                 return &bpf_redirect_proto;
3996         case BPF_FUNC_clone_redirect:
3997                 return &bpf_clone_redirect_proto;
3998         case BPF_FUNC_skb_change_tail:
3999                 return &bpf_skb_change_tail_proto;
4000         case BPF_FUNC_skb_change_head:
4001                 return &bpf_skb_change_head_proto;
4002         case BPF_FUNC_skb_store_bytes:
4003                 return &bpf_skb_store_bytes_proto;
4004         case BPF_FUNC_csum_update:
4005                 return &bpf_csum_update_proto;
4006         case BPF_FUNC_l3_csum_replace:
4007                 return &bpf_l3_csum_replace_proto;
4008         case BPF_FUNC_l4_csum_replace:
4009                 return &bpf_l4_csum_replace_proto;
4010         case BPF_FUNC_set_hash_invalid:
4011                 return &bpf_set_hash_invalid_proto;
4012         default:
4013                 return lwt_inout_func_proto(func_id, prog);
4014         }
4015 }
4016
4017 static bool bpf_skb_is_valid_access(int off, int size, enum bpf_access_type type,
4018                                     const struct bpf_prog *prog,
4019                                     struct bpf_insn_access_aux *info)
4020 {
4021         const int size_default = sizeof(__u32);
4022
4023         if (off < 0 || off >= sizeof(struct __sk_buff))
4024                 return false;
4025
4026         /* The verifier guarantees that size > 0. */
4027         if (off % size != 0)
4028                 return false;
4029
4030         switch (off) {
4031         case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
4032                 if (off + size > offsetofend(struct __sk_buff, cb[4]))
4033                         return false;
4034                 break;
4035         case bpf_ctx_range_till(struct __sk_buff, remote_ip6[0], remote_ip6[3]):
4036         case bpf_ctx_range_till(struct __sk_buff, local_ip6[0], local_ip6[3]):
4037         case bpf_ctx_range_till(struct __sk_buff, remote_ip4, remote_ip4):
4038         case bpf_ctx_range_till(struct __sk_buff, local_ip4, local_ip4):
4039         case bpf_ctx_range(struct __sk_buff, data):
4040         case bpf_ctx_range(struct __sk_buff, data_meta):
4041         case bpf_ctx_range(struct __sk_buff, data_end):
4042                 if (size != size_default)
4043                         return false;
4044                 break;
4045         default:
4046                 /* Only narrow read access allowed for now. */
4047                 if (type == BPF_WRITE) {
4048                         if (size != size_default)
4049                                 return false;
4050                 } else {
4051                         bpf_ctx_record_field_size(info, size_default);
4052                         if (!bpf_ctx_narrow_access_ok(off, size, size_default))
4053                                 return false;
4054                 }
4055         }
4056
4057         return true;
4058 }
4059
4060 static bool sk_filter_is_valid_access(int off, int size,
4061                                       enum bpf_access_type type,
4062                                       const struct bpf_prog *prog,
4063                                       struct bpf_insn_access_aux *info)
4064 {
4065         switch (off) {
4066         case bpf_ctx_range(struct __sk_buff, tc_classid):
4067         case bpf_ctx_range(struct __sk_buff, data):
4068         case bpf_ctx_range(struct __sk_buff, data_meta):
4069         case bpf_ctx_range(struct __sk_buff, data_end):
4070         case bpf_ctx_range_till(struct __sk_buff, family, local_port):
4071                 return false;
4072         }
4073
4074         if (type == BPF_WRITE) {
4075                 switch (off) {
4076                 case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
4077                         break;
4078                 default:
4079                         return false;
4080                 }
4081         }
4082
4083         return bpf_skb_is_valid_access(off, size, type, prog, info);
4084 }
4085
4086 static bool lwt_is_valid_access(int off, int size,
4087                                 enum bpf_access_type type,
4088                                 const struct bpf_prog *prog,
4089                                 struct bpf_insn_access_aux *info)
4090 {
4091         switch (off) {
4092         case bpf_ctx_range(struct __sk_buff, tc_classid):
4093         case bpf_ctx_range_till(struct __sk_buff, family, local_port):
4094         case bpf_ctx_range(struct __sk_buff, data_meta):
4095                 return false;
4096         }
4097
4098         if (type == BPF_WRITE) {
4099                 switch (off) {
4100                 case bpf_ctx_range(struct __sk_buff, mark):
4101                 case bpf_ctx_range(struct __sk_buff, priority):
4102                 case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
4103                         break;
4104                 default:
4105                         return false;
4106                 }
4107         }
4108
4109         switch (off) {
4110         case bpf_ctx_range(struct __sk_buff, data):
4111                 info->reg_type = PTR_TO_PACKET;
4112                 break;
4113         case bpf_ctx_range(struct __sk_buff, data_end):
4114                 info->reg_type = PTR_TO_PACKET_END;
4115                 break;
4116         }
4117
4118         return bpf_skb_is_valid_access(off, size, type, prog, info);
4119 }
4120
4121
4122 /* Attach type specific accesses */
4123 static bool __sock_filter_check_attach_type(int off,
4124                                             enum bpf_access_type access_type,
4125                                             enum bpf_attach_type attach_type)
4126 {
4127         switch (off) {
4128         case offsetof(struct bpf_sock, bound_dev_if):
4129         case offsetof(struct bpf_sock, mark):
4130         case offsetof(struct bpf_sock, priority):
4131                 switch (attach_type) {
4132                 case BPF_CGROUP_INET_SOCK_CREATE:
4133                         goto full_access;
4134                 default:
4135                         return false;
4136                 }
4137         case bpf_ctx_range(struct bpf_sock, src_ip4):
4138                 switch (attach_type) {
4139                 case BPF_CGROUP_INET4_POST_BIND:
4140                         goto read_only;
4141                 default:
4142                         return false;
4143                 }
4144         case bpf_ctx_range_till(struct bpf_sock, src_ip6[0], src_ip6[3]):
4145                 switch (attach_type) {
4146                 case BPF_CGROUP_INET6_POST_BIND:
4147                         goto read_only;
4148                 default:
4149                         return false;
4150                 }
4151         case bpf_ctx_range(struct bpf_sock, src_port):
4152                 switch (attach_type) {
4153                 case BPF_CGROUP_INET4_POST_BIND:
4154                 case BPF_CGROUP_INET6_POST_BIND:
4155                         goto read_only;
4156                 default:
4157                         return false;
4158                 }
4159         }
4160 read_only:
4161         return access_type == BPF_READ;
4162 full_access:
4163         return true;
4164 }
4165
4166 static bool __sock_filter_check_size(int off, int size,
4167                                      struct bpf_insn_access_aux *info)
4168 {
4169         const int size_default = sizeof(__u32);
4170
4171         switch (off) {
4172         case bpf_ctx_range(struct bpf_sock, src_ip4):
4173         case bpf_ctx_range_till(struct bpf_sock, src_ip6[0], src_ip6[3]):
4174                 bpf_ctx_record_field_size(info, size_default);
4175                 return bpf_ctx_narrow_access_ok(off, size, size_default);
4176         }
4177
4178         return size == size_default;
4179 }
4180
4181 static bool sock_filter_is_valid_access(int off, int size,
4182                                         enum bpf_access_type type,
4183                                         const struct bpf_prog *prog,
4184                                         struct bpf_insn_access_aux *info)
4185 {
4186         if (off < 0 || off >= sizeof(struct bpf_sock))
4187                 return false;
4188         if (off % size != 0)
4189                 return false;
4190         if (!__sock_filter_check_attach_type(off, type,
4191                                              prog->expected_attach_type))
4192                 return false;
4193         if (!__sock_filter_check_size(off, size, info))
4194                 return false;
4195         return true;
4196 }
4197
4198 static int bpf_unclone_prologue(struct bpf_insn *insn_buf, bool direct_write,
4199                                 const struct bpf_prog *prog, int drop_verdict)
4200 {
4201         struct bpf_insn *insn = insn_buf;
4202
4203         if (!direct_write)
4204                 return 0;
4205
4206         /* if (!skb->cloned)
4207          *       goto start;
4208          *
4209          * (Fast-path, otherwise approximation that we might be
4210          *  a clone, do the rest in helper.)
4211          */
4212         *insn++ = BPF_LDX_MEM(BPF_B, BPF_REG_6, BPF_REG_1, CLONED_OFFSET());
4213         *insn++ = BPF_ALU32_IMM(BPF_AND, BPF_REG_6, CLONED_MASK);
4214         *insn++ = BPF_JMP_IMM(BPF_JEQ, BPF_REG_6, 0, 7);
4215
4216         /* ret = bpf_skb_pull_data(skb, 0); */
4217         *insn++ = BPF_MOV64_REG(BPF_REG_6, BPF_REG_1);
4218         *insn++ = BPF_ALU64_REG(BPF_XOR, BPF_REG_2, BPF_REG_2);
4219         *insn++ = BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
4220                                BPF_FUNC_skb_pull_data);
4221         /* if (!ret)
4222          *      goto restore;
4223          * return TC_ACT_SHOT;
4224          */
4225         *insn++ = BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2);
4226         *insn++ = BPF_ALU32_IMM(BPF_MOV, BPF_REG_0, drop_verdict);
4227         *insn++ = BPF_EXIT_INSN();
4228
4229         /* restore: */
4230         *insn++ = BPF_MOV64_REG(BPF_REG_1, BPF_REG_6);
4231         /* start: */
4232         *insn++ = prog->insnsi[0];
4233
4234         return insn - insn_buf;
4235 }
4236
4237 static int tc_cls_act_prologue(struct bpf_insn *insn_buf, bool direct_write,
4238                                const struct bpf_prog *prog)
4239 {
4240         return bpf_unclone_prologue(insn_buf, direct_write, prog, TC_ACT_SHOT);
4241 }
4242
4243 static bool tc_cls_act_is_valid_access(int off, int size,
4244                                        enum bpf_access_type type,
4245                                        const struct bpf_prog *prog,
4246                                        struct bpf_insn_access_aux *info)
4247 {
4248         if (type == BPF_WRITE) {
4249                 switch (off) {
4250                 case bpf_ctx_range(struct __sk_buff, mark):
4251                 case bpf_ctx_range(struct __sk_buff, tc_index):
4252                 case bpf_ctx_range(struct __sk_buff, priority):
4253                 case bpf_ctx_range(struct __sk_buff, tc_classid):
4254                 case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
4255                         break;
4256                 default:
4257                         return false;
4258                 }
4259         }
4260
4261         switch (off) {
4262         case bpf_ctx_range(struct __sk_buff, data):
4263                 info->reg_type = PTR_TO_PACKET;
4264                 break;
4265         case bpf_ctx_range(struct __sk_buff, data_meta):
4266                 info->reg_type = PTR_TO_PACKET_META;
4267                 break;
4268         case bpf_ctx_range(struct __sk_buff, data_end):
4269                 info->reg_type = PTR_TO_PACKET_END;
4270                 break;
4271         case bpf_ctx_range_till(struct __sk_buff, family, local_port):
4272                 return false;
4273         }
4274
4275         return bpf_skb_is_valid_access(off, size, type, prog, info);
4276 }
4277
4278 static bool __is_valid_xdp_access(int off, int size)
4279 {
4280         if (off < 0 || off >= sizeof(struct xdp_md))
4281                 return false;
4282         if (off % size != 0)
4283                 return false;
4284         if (size != sizeof(__u32))
4285                 return false;
4286
4287         return true;
4288 }
4289
4290 static bool xdp_is_valid_access(int off, int size,
4291                                 enum bpf_access_type type,
4292                                 const struct bpf_prog *prog,
4293                                 struct bpf_insn_access_aux *info)
4294 {
4295         if (type == BPF_WRITE)
4296                 return false;
4297
4298         switch (off) {
4299         case offsetof(struct xdp_md, data):
4300                 info->reg_type = PTR_TO_PACKET;
4301                 break;
4302         case offsetof(struct xdp_md, data_meta):
4303                 info->reg_type = PTR_TO_PACKET_META;
4304                 break;
4305         case offsetof(struct xdp_md, data_end):
4306                 info->reg_type = PTR_TO_PACKET_END;
4307                 break;
4308         }
4309
4310         return __is_valid_xdp_access(off, size);
4311 }
4312
4313 void bpf_warn_invalid_xdp_action(u32 act)
4314 {
4315         const u32 act_max = XDP_REDIRECT;
4316
4317         WARN_ONCE(1, "%s XDP return value %u, expect packet loss!\n",
4318                   act > act_max ? "Illegal" : "Driver unsupported",
4319                   act);
4320 }
4321 EXPORT_SYMBOL_GPL(bpf_warn_invalid_xdp_action);
4322
4323 static bool sock_addr_is_valid_access(int off, int size,
4324                                       enum bpf_access_type type,
4325                                       const struct bpf_prog *prog,
4326                                       struct bpf_insn_access_aux *info)
4327 {
4328         const int size_default = sizeof(__u32);
4329
4330         if (off < 0 || off >= sizeof(struct bpf_sock_addr))
4331                 return false;
4332         if (off % size != 0)
4333                 return false;
4334
4335         /* Disallow access to IPv6 fields from IPv4 contex and vise
4336          * versa.
4337          */
4338         switch (off) {
4339         case bpf_ctx_range(struct bpf_sock_addr, user_ip4):
4340                 switch (prog->expected_attach_type) {
4341                 case BPF_CGROUP_INET4_BIND:
4342                 case BPF_CGROUP_INET4_CONNECT:
4343                         break;
4344                 default:
4345                         return false;
4346                 }
4347                 break;
4348         case bpf_ctx_range_till(struct bpf_sock_addr, user_ip6[0], user_ip6[3]):
4349                 switch (prog->expected_attach_type) {
4350                 case BPF_CGROUP_INET6_BIND:
4351                 case BPF_CGROUP_INET6_CONNECT:
4352                         break;
4353                 default:
4354                         return false;
4355                 }
4356                 break;
4357         }
4358
4359         switch (off) {
4360         case bpf_ctx_range(struct bpf_sock_addr, user_ip4):
4361         case bpf_ctx_range_till(struct bpf_sock_addr, user_ip6[0], user_ip6[3]):
4362                 /* Only narrow read access allowed for now. */
4363                 if (type == BPF_READ) {
4364                         bpf_ctx_record_field_size(info, size_default);
4365                         if (!bpf_ctx_narrow_access_ok(off, size, size_default))
4366                                 return false;
4367                 } else {
4368                         if (size != size_default)
4369                                 return false;
4370                 }
4371                 break;
4372         case bpf_ctx_range(struct bpf_sock_addr, user_port):
4373                 if (size != size_default)
4374                         return false;
4375                 break;
4376         default:
4377                 if (type == BPF_READ) {
4378                         if (size != size_default)
4379                                 return false;
4380                 } else {
4381                         return false;
4382                 }
4383         }
4384
4385         return true;
4386 }
4387
4388 static bool sock_ops_is_valid_access(int off, int size,
4389                                      enum bpf_access_type type,
4390                                      const struct bpf_prog *prog,
4391                                      struct bpf_insn_access_aux *info)
4392 {
4393         const int size_default = sizeof(__u32);
4394
4395         if (off < 0 || off >= sizeof(struct bpf_sock_ops))
4396                 return false;
4397
4398         /* The verifier guarantees that size > 0. */
4399         if (off % size != 0)
4400                 return false;
4401
4402         if (type == BPF_WRITE) {
4403                 switch (off) {
4404                 case offsetof(struct bpf_sock_ops, reply):
4405                 case offsetof(struct bpf_sock_ops, sk_txhash):
4406                         if (size != size_default)
4407                                 return false;
4408                         break;
4409                 default:
4410                         return false;
4411                 }
4412         } else {
4413                 switch (off) {
4414                 case bpf_ctx_range_till(struct bpf_sock_ops, bytes_received,
4415                                         bytes_acked):
4416                         if (size != sizeof(__u64))
4417                                 return false;
4418                         break;
4419                 default:
4420                         if (size != size_default)
4421                                 return false;
4422                         break;
4423                 }
4424         }
4425
4426         return true;
4427 }
4428
4429 static int sk_skb_prologue(struct bpf_insn *insn_buf, bool direct_write,
4430                            const struct bpf_prog *prog)
4431 {
4432         return bpf_unclone_prologue(insn_buf, direct_write, prog, SK_DROP);
4433 }
4434
4435 static bool sk_skb_is_valid_access(int off, int size,
4436                                    enum bpf_access_type type,
4437                                    const struct bpf_prog *prog,
4438                                    struct bpf_insn_access_aux *info)
4439 {
4440         switch (off) {
4441         case bpf_ctx_range(struct __sk_buff, tc_classid):
4442         case bpf_ctx_range(struct __sk_buff, data_meta):
4443                 return false;
4444         }
4445
4446         if (type == BPF_WRITE) {
4447                 switch (off) {
4448                 case bpf_ctx_range(struct __sk_buff, tc_index):
4449                 case bpf_ctx_range(struct __sk_buff, priority):
4450                         break;
4451                 default:
4452                         return false;
4453                 }
4454         }
4455
4456         switch (off) {
4457         case bpf_ctx_range(struct __sk_buff, mark):
4458                 return false;
4459         case bpf_ctx_range(struct __sk_buff, data):
4460                 info->reg_type = PTR_TO_PACKET;
4461                 break;
4462         case bpf_ctx_range(struct __sk_buff, data_end):
4463                 info->reg_type = PTR_TO_PACKET_END;
4464                 break;
4465         }
4466
4467         return bpf_skb_is_valid_access(off, size, type, prog, info);
4468 }
4469
4470 static bool sk_msg_is_valid_access(int off, int size,
4471                                    enum bpf_access_type type,
4472                                    const struct bpf_prog *prog,
4473                                    struct bpf_insn_access_aux *info)
4474 {
4475         if (type == BPF_WRITE)
4476                 return false;
4477
4478         switch (off) {
4479         case offsetof(struct sk_msg_md, data):
4480                 info->reg_type = PTR_TO_PACKET;
4481                 break;
4482         case offsetof(struct sk_msg_md, data_end):
4483                 info->reg_type = PTR_TO_PACKET_END;
4484                 break;
4485         }
4486
4487         if (off < 0 || off >= sizeof(struct sk_msg_md))
4488                 return false;
4489         if (off % size != 0)
4490                 return false;
4491         if (size != sizeof(__u64))
4492                 return false;
4493
4494         return true;
4495 }
4496
4497 static u32 bpf_convert_ctx_access(enum bpf_access_type type,
4498                                   const struct bpf_insn *si,
4499                                   struct bpf_insn *insn_buf,
4500                                   struct bpf_prog *prog, u32 *target_size)
4501 {
4502         struct bpf_insn *insn = insn_buf;
4503         int off;
4504
4505         switch (si->off) {
4506         case offsetof(struct __sk_buff, len):
4507                 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
4508                                       bpf_target_off(struct sk_buff, len, 4,
4509                                                      target_size));
4510                 break;
4511
4512         case offsetof(struct __sk_buff, protocol):
4513                 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
4514                                       bpf_target_off(struct sk_buff, protocol, 2,
4515                                                      target_size));
4516                 break;
4517
4518         case offsetof(struct __sk_buff, vlan_proto):
4519                 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
4520                                       bpf_target_off(struct sk_buff, vlan_proto, 2,
4521                                                      target_size));
4522                 break;
4523
4524         case offsetof(struct __sk_buff, priority):
4525                 if (type == BPF_WRITE)
4526                         *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
4527                                               bpf_target_off(struct sk_buff, priority, 4,
4528                                                              target_size));
4529                 else
4530                         *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
4531                                               bpf_target_off(struct sk_buff, priority, 4,
4532                                                              target_size));
4533                 break;
4534
4535         case offsetof(struct __sk_buff, ingress_ifindex):
4536                 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
4537                                       bpf_target_off(struct sk_buff, skb_iif, 4,
4538                                                      target_size));
4539                 break;
4540
4541         case offsetof(struct __sk_buff, ifindex):
4542                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev),
4543                                       si->dst_reg, si->src_reg,
4544                                       offsetof(struct sk_buff, dev));
4545                 *insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
4546                 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
4547                                       bpf_target_off(struct net_device, ifindex, 4,
4548                                                      target_size));
4549                 break;
4550
4551         case offsetof(struct __sk_buff, hash):
4552                 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
4553                                       bpf_target_off(struct sk_buff, hash, 4,
4554                                                      target_size));
4555                 break;
4556
4557         case offsetof(struct __sk_buff, mark):
4558                 if (type == BPF_WRITE)
4559                         *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
4560                                               bpf_target_off(struct sk_buff, mark, 4,
4561                                                              target_size));
4562                 else
4563                         *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
4564                                               bpf_target_off(struct sk_buff, mark, 4,
4565                                                              target_size));
4566                 break;
4567
4568         case offsetof(struct __sk_buff, pkt_type):
4569                 *target_size = 1;
4570                 *insn++ = BPF_LDX_MEM(BPF_B, si->dst_reg, si->src_reg,
4571                                       PKT_TYPE_OFFSET());
4572                 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, PKT_TYPE_MAX);
4573 #ifdef __BIG_ENDIAN_BITFIELD
4574                 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, 5);
4575 #endif
4576                 break;
4577
4578         case offsetof(struct __sk_buff, queue_mapping):
4579                 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
4580                                       bpf_target_off(struct sk_buff, queue_mapping, 2,
4581                                                      target_size));
4582                 break;
4583
4584         case offsetof(struct __sk_buff, vlan_present):
4585         case offsetof(struct __sk_buff, vlan_tci):
4586                 BUILD_BUG_ON(VLAN_TAG_PRESENT != 0x1000);
4587
4588                 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
4589                                       bpf_target_off(struct sk_buff, vlan_tci, 2,
4590                                                      target_size));
4591                 if (si->off == offsetof(struct __sk_buff, vlan_tci)) {
4592                         *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg,
4593                                                 ~VLAN_TAG_PRESENT);
4594                 } else {
4595                         *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, 12);
4596                         *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, 1);
4597                 }
4598                 break;
4599
4600         case offsetof(struct __sk_buff, cb[0]) ...
4601              offsetofend(struct __sk_buff, cb[4]) - 1:
4602                 BUILD_BUG_ON(FIELD_SIZEOF(struct qdisc_skb_cb, data) < 20);
4603                 BUILD_BUG_ON((offsetof(struct sk_buff, cb) +
4604                               offsetof(struct qdisc_skb_cb, data)) %
4605                              sizeof(__u64));
4606
4607                 prog->cb_access = 1;
4608                 off  = si->off;
4609                 off -= offsetof(struct __sk_buff, cb[0]);
4610                 off += offsetof(struct sk_buff, cb);
4611                 off += offsetof(struct qdisc_skb_cb, data);
4612                 if (type == BPF_WRITE)
4613                         *insn++ = BPF_STX_MEM(BPF_SIZE(si->code), si->dst_reg,
4614                                               si->src_reg, off);
4615                 else
4616                         *insn++ = BPF_LDX_MEM(BPF_SIZE(si->code), si->dst_reg,
4617                                               si->src_reg, off);
4618                 break;
4619
4620         case offsetof(struct __sk_buff, tc_classid):
4621                 BUILD_BUG_ON(FIELD_SIZEOF(struct qdisc_skb_cb, tc_classid) != 2);
4622
4623                 off  = si->off;
4624                 off -= offsetof(struct __sk_buff, tc_classid);
4625                 off += offsetof(struct sk_buff, cb);
4626                 off += offsetof(struct qdisc_skb_cb, tc_classid);
4627                 *target_size = 2;
4628                 if (type == BPF_WRITE)
4629                         *insn++ = BPF_STX_MEM(BPF_H, si->dst_reg,
4630                                               si->src_reg, off);
4631                 else
4632                         *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg,
4633                                               si->src_reg, off);
4634                 break;
4635
4636         case offsetof(struct __sk_buff, data):
4637                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data),
4638                                       si->dst_reg, si->src_reg,
4639                                       offsetof(struct sk_buff, data));
4640                 break;
4641
4642         case offsetof(struct __sk_buff, data_meta):
4643                 off  = si->off;
4644                 off -= offsetof(struct __sk_buff, data_meta);
4645                 off += offsetof(struct sk_buff, cb);
4646                 off += offsetof(struct bpf_skb_data_end, data_meta);
4647                 *insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg,
4648                                       si->src_reg, off);
4649                 break;
4650
4651         case offsetof(struct __sk_buff, data_end):
4652                 off  = si->off;
4653                 off -= offsetof(struct __sk_buff, data_end);
4654                 off += offsetof(struct sk_buff, cb);
4655                 off += offsetof(struct bpf_skb_data_end, data_end);
4656                 *insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg,
4657                                       si->src_reg, off);
4658                 break;
4659
4660         case offsetof(struct __sk_buff, tc_index):
4661 #ifdef CONFIG_NET_SCHED
4662                 if (type == BPF_WRITE)
4663                         *insn++ = BPF_STX_MEM(BPF_H, si->dst_reg, si->src_reg,
4664                                               bpf_target_off(struct sk_buff, tc_index, 2,
4665                                                              target_size));
4666                 else
4667                         *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
4668                                               bpf_target_off(struct sk_buff, tc_index, 2,
4669                                                              target_size));
4670 #else
4671                 *target_size = 2;
4672                 if (type == BPF_WRITE)
4673                         *insn++ = BPF_MOV64_REG(si->dst_reg, si->dst_reg);
4674                 else
4675                         *insn++ = BPF_MOV64_IMM(si->dst_reg, 0);
4676 #endif
4677                 break;
4678
4679         case offsetof(struct __sk_buff, napi_id):
4680 #if defined(CONFIG_NET_RX_BUSY_POLL)
4681                 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
4682                                       bpf_target_off(struct sk_buff, napi_id, 4,
4683                                                      target_size));
4684                 *insn++ = BPF_JMP_IMM(BPF_JGE, si->dst_reg, MIN_NAPI_ID, 1);
4685                 *insn++ = BPF_MOV64_IMM(si->dst_reg, 0);
4686 #else
4687                 *target_size = 4;
4688                 *insn++ = BPF_MOV64_IMM(si->dst_reg, 0);
4689 #endif
4690                 break;
4691         case offsetof(struct __sk_buff, family):
4692                 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_family) != 2);
4693
4694                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
4695                                       si->dst_reg, si->src_reg,
4696                                       offsetof(struct sk_buff, sk));
4697                 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
4698                                       bpf_target_off(struct sock_common,
4699                                                      skc_family,
4700                                                      2, target_size));
4701                 break;
4702         case offsetof(struct __sk_buff, remote_ip4):
4703                 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_daddr) != 4);
4704
4705                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
4706                                       si->dst_reg, si->src_reg,
4707                                       offsetof(struct sk_buff, sk));
4708                 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
4709                                       bpf_target_off(struct sock_common,
4710                                                      skc_daddr,
4711                                                      4, target_size));
4712                 break;
4713         case offsetof(struct __sk_buff, local_ip4):
4714                 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common,
4715                                           skc_rcv_saddr) != 4);
4716
4717                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
4718                                       si->dst_reg, si->src_reg,
4719                                       offsetof(struct sk_buff, sk));
4720                 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
4721                                       bpf_target_off(struct sock_common,
4722                                                      skc_rcv_saddr,
4723                                                      4, target_size));
4724                 break;
4725         case offsetof(struct __sk_buff, remote_ip6[0]) ...
4726              offsetof(struct __sk_buff, remote_ip6[3]):
4727 #if IS_ENABLED(CONFIG_IPV6)
4728                 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common,
4729                                           skc_v6_daddr.s6_addr32[0]) != 4);
4730
4731                 off = si->off;
4732                 off -= offsetof(struct __sk_buff, remote_ip6[0]);
4733
4734                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
4735                                       si->dst_reg, si->src_reg,
4736                                       offsetof(struct sk_buff, sk));
4737                 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
4738                                       offsetof(struct sock_common,
4739                                                skc_v6_daddr.s6_addr32[0]) +
4740                                       off);
4741 #else
4742                 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
4743 #endif
4744                 break;
4745         case offsetof(struct __sk_buff, local_ip6[0]) ...
4746              offsetof(struct __sk_buff, local_ip6[3]):
4747 #if IS_ENABLED(CONFIG_IPV6)
4748                 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common,
4749                                           skc_v6_rcv_saddr.s6_addr32[0]) != 4);
4750
4751                 off = si->off;
4752                 off -= offsetof(struct __sk_buff, local_ip6[0]);
4753
4754                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
4755                                       si->dst_reg, si->src_reg,
4756                                       offsetof(struct sk_buff, sk));
4757                 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
4758                                       offsetof(struct sock_common,
4759                                                skc_v6_rcv_saddr.s6_addr32[0]) +
4760                                       off);
4761 #else
4762                 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
4763 #endif
4764                 break;
4765
4766         case offsetof(struct __sk_buff, remote_port):
4767                 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_dport) != 2);
4768
4769                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
4770                                       si->dst_reg, si->src_reg,
4771                                       offsetof(struct sk_buff, sk));
4772                 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
4773                                       bpf_target_off(struct sock_common,
4774                                                      skc_dport,
4775                                                      2, target_size));
4776 #ifndef __BIG_ENDIAN_BITFIELD
4777                 *insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16);
4778 #endif
4779                 break;
4780
4781         case offsetof(struct __sk_buff, local_port):
4782                 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_num) != 2);
4783
4784                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
4785                                       si->dst_reg, si->src_reg,
4786                                       offsetof(struct sk_buff, sk));
4787                 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
4788                                       bpf_target_off(struct sock_common,
4789                                                      skc_num, 2, target_size));
4790                 break;
4791         }
4792
4793         return insn - insn_buf;
4794 }
4795
4796 static u32 sock_filter_convert_ctx_access(enum bpf_access_type type,
4797                                           const struct bpf_insn *si,
4798                                           struct bpf_insn *insn_buf,
4799                                           struct bpf_prog *prog, u32 *target_size)
4800 {
4801         struct bpf_insn *insn = insn_buf;
4802         int off;
4803
4804         switch (si->off) {
4805         case offsetof(struct bpf_sock, bound_dev_if):
4806                 BUILD_BUG_ON(FIELD_SIZEOF(struct sock, sk_bound_dev_if) != 4);
4807
4808                 if (type == BPF_WRITE)
4809                         *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
4810                                         offsetof(struct sock, sk_bound_dev_if));
4811                 else
4812                         *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
4813                                       offsetof(struct sock, sk_bound_dev_if));
4814                 break;
4815
4816         case offsetof(struct bpf_sock, mark):
4817                 BUILD_BUG_ON(FIELD_SIZEOF(struct sock, sk_mark) != 4);
4818
4819                 if (type == BPF_WRITE)
4820                         *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
4821                                         offsetof(struct sock, sk_mark));
4822                 else
4823                         *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
4824                                       offsetof(struct sock, sk_mark));
4825                 break;
4826
4827         case offsetof(struct bpf_sock, priority):
4828                 BUILD_BUG_ON(FIELD_SIZEOF(struct sock, sk_priority) != 4);
4829
4830                 if (type == BPF_WRITE)
4831                         *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
4832                                         offsetof(struct sock, sk_priority));
4833                 else
4834                         *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
4835                                       offsetof(struct sock, sk_priority));
4836                 break;
4837
4838         case offsetof(struct bpf_sock, family):
4839                 BUILD_BUG_ON(FIELD_SIZEOF(struct sock, sk_family) != 2);
4840
4841                 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
4842                                       offsetof(struct sock, sk_family));
4843                 break;
4844
4845         case offsetof(struct bpf_sock, type):
4846                 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
4847                                       offsetof(struct sock, __sk_flags_offset));
4848                 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, SK_FL_TYPE_MASK);
4849                 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, SK_FL_TYPE_SHIFT);
4850                 break;
4851
4852         case offsetof(struct bpf_sock, protocol):
4853                 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
4854                                       offsetof(struct sock, __sk_flags_offset));
4855                 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, SK_FL_PROTO_MASK);
4856                 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, SK_FL_PROTO_SHIFT);
4857                 break;
4858
4859         case offsetof(struct bpf_sock, src_ip4):
4860                 *insn++ = BPF_LDX_MEM(
4861                         BPF_SIZE(si->code), si->dst_reg, si->src_reg,
4862                         bpf_target_off(struct sock_common, skc_rcv_saddr,
4863                                        FIELD_SIZEOF(struct sock_common,
4864                                                     skc_rcv_saddr),
4865                                        target_size));
4866                 break;
4867
4868         case bpf_ctx_range_till(struct bpf_sock, src_ip6[0], src_ip6[3]):
4869 #if IS_ENABLED(CONFIG_IPV6)
4870                 off = si->off;
4871                 off -= offsetof(struct bpf_sock, src_ip6[0]);
4872                 *insn++ = BPF_LDX_MEM(
4873                         BPF_SIZE(si->code), si->dst_reg, si->src_reg,
4874                         bpf_target_off(
4875                                 struct sock_common,
4876                                 skc_v6_rcv_saddr.s6_addr32[0],
4877                                 FIELD_SIZEOF(struct sock_common,
4878                                              skc_v6_rcv_saddr.s6_addr32[0]),
4879                                 target_size) + off);
4880 #else
4881                 (void)off;
4882                 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
4883 #endif
4884                 break;
4885
4886         case offsetof(struct bpf_sock, src_port):
4887                 *insn++ = BPF_LDX_MEM(
4888                         BPF_FIELD_SIZEOF(struct sock_common, skc_num),
4889                         si->dst_reg, si->src_reg,
4890                         bpf_target_off(struct sock_common, skc_num,
4891                                        FIELD_SIZEOF(struct sock_common,
4892                                                     skc_num),
4893                                        target_size));
4894                 break;
4895         }
4896
4897         return insn - insn_buf;
4898 }
4899
4900 static u32 tc_cls_act_convert_ctx_access(enum bpf_access_type type,
4901                                          const struct bpf_insn *si,
4902                                          struct bpf_insn *insn_buf,
4903                                          struct bpf_prog *prog, u32 *target_size)
4904 {
4905         struct bpf_insn *insn = insn_buf;
4906
4907         switch (si->off) {
4908         case offsetof(struct __sk_buff, ifindex):
4909                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev),
4910                                       si->dst_reg, si->src_reg,
4911                                       offsetof(struct sk_buff, dev));
4912                 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
4913                                       bpf_target_off(struct net_device, ifindex, 4,
4914                                                      target_size));
4915                 break;
4916         default:
4917                 return bpf_convert_ctx_access(type, si, insn_buf, prog,
4918                                               target_size);
4919         }
4920
4921         return insn - insn_buf;
4922 }
4923
4924 static u32 xdp_convert_ctx_access(enum bpf_access_type type,
4925                                   const struct bpf_insn *si,
4926                                   struct bpf_insn *insn_buf,
4927                                   struct bpf_prog *prog, u32 *target_size)
4928 {
4929         struct bpf_insn *insn = insn_buf;
4930
4931         switch (si->off) {
4932         case offsetof(struct xdp_md, data):
4933                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data),
4934                                       si->dst_reg, si->src_reg,
4935                                       offsetof(struct xdp_buff, data));
4936                 break;
4937         case offsetof(struct xdp_md, data_meta):
4938                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data_meta),
4939                                       si->dst_reg, si->src_reg,
4940                                       offsetof(struct xdp_buff, data_meta));
4941                 break;
4942         case offsetof(struct xdp_md, data_end):
4943                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data_end),
4944                                       si->dst_reg, si->src_reg,
4945                                       offsetof(struct xdp_buff, data_end));
4946                 break;
4947         case offsetof(struct xdp_md, ingress_ifindex):
4948                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, rxq),
4949                                       si->dst_reg, si->src_reg,
4950                                       offsetof(struct xdp_buff, rxq));
4951                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_rxq_info, dev),
4952                                       si->dst_reg, si->dst_reg,
4953                                       offsetof(struct xdp_rxq_info, dev));
4954                 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
4955                                       offsetof(struct net_device, ifindex));
4956                 break;
4957         case offsetof(struct xdp_md, rx_queue_index):
4958                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, rxq),
4959                                       si->dst_reg, si->src_reg,
4960                                       offsetof(struct xdp_buff, rxq));
4961                 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
4962                                       offsetof(struct xdp_rxq_info,
4963                                                queue_index));
4964                 break;
4965         }
4966
4967         return insn - insn_buf;
4968 }
4969
4970 /* SOCK_ADDR_LOAD_NESTED_FIELD() loads Nested Field S.F.NF where S is type of
4971  * context Structure, F is Field in context structure that contains a pointer
4972  * to Nested Structure of type NS that has the field NF.
4973  *
4974  * SIZE encodes the load size (BPF_B, BPF_H, etc). It's up to caller to make
4975  * sure that SIZE is not greater than actual size of S.F.NF.
4976  *
4977  * If offset OFF is provided, the load happens from that offset relative to
4978  * offset of NF.
4979  */
4980 #define SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF(S, NS, F, NF, SIZE, OFF)          \
4981         do {                                                                   \
4982                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(S, F), si->dst_reg,     \
4983                                       si->src_reg, offsetof(S, F));            \
4984                 *insn++ = BPF_LDX_MEM(                                         \
4985                         SIZE, si->dst_reg, si->dst_reg,                        \
4986                         bpf_target_off(NS, NF, FIELD_SIZEOF(NS, NF),           \
4987                                        target_size)                            \
4988                                 + OFF);                                        \
4989         } while (0)
4990
4991 #define SOCK_ADDR_LOAD_NESTED_FIELD(S, NS, F, NF)                              \
4992         SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF(S, NS, F, NF,                     \
4993                                              BPF_FIELD_SIZEOF(NS, NF), 0)
4994
4995 /* SOCK_ADDR_STORE_NESTED_FIELD_OFF() has semantic similar to
4996  * SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF() but for store operation.
4997  *
4998  * It doesn't support SIZE argument though since narrow stores are not
4999  * supported for now.
5000  *
5001  * In addition it uses Temporary Field TF (member of struct S) as the 3rd
5002  * "register" since two registers available in convert_ctx_access are not
5003  * enough: we can't override neither SRC, since it contains value to store, nor
5004  * DST since it contains pointer to context that may be used by later
5005  * instructions. But we need a temporary place to save pointer to nested
5006  * structure whose field we want to store to.
5007  */
5008 #define SOCK_ADDR_STORE_NESTED_FIELD_OFF(S, NS, F, NF, OFF, TF)                \
5009         do {                                                                   \
5010                 int tmp_reg = BPF_REG_9;                                       \
5011                 if (si->src_reg == tmp_reg || si->dst_reg == tmp_reg)          \
5012                         --tmp_reg;                                             \
5013                 if (si->src_reg == tmp_reg || si->dst_reg == tmp_reg)          \
5014                         --tmp_reg;                                             \
5015                 *insn++ = BPF_STX_MEM(BPF_DW, si->dst_reg, tmp_reg,            \
5016                                       offsetof(S, TF));                        \
5017                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(S, F), tmp_reg,         \
5018                                       si->dst_reg, offsetof(S, F));            \
5019                 *insn++ = BPF_STX_MEM(                                         \
5020                         BPF_FIELD_SIZEOF(NS, NF), tmp_reg, si->src_reg,        \
5021                         bpf_target_off(NS, NF, FIELD_SIZEOF(NS, NF),           \
5022                                        target_size)                            \
5023                                 + OFF);                                        \
5024                 *insn++ = BPF_LDX_MEM(BPF_DW, tmp_reg, si->dst_reg,            \
5025                                       offsetof(S, TF));                        \
5026         } while (0)
5027
5028 #define SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(S, NS, F, NF, SIZE, OFF, \
5029                                                       TF)                      \
5030         do {                                                                   \
5031                 if (type == BPF_WRITE) {                                       \
5032                         SOCK_ADDR_STORE_NESTED_FIELD_OFF(S, NS, F, NF, OFF,    \
5033                                                          TF);                  \
5034                 } else {                                                       \
5035                         SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF(                  \
5036                                 S, NS, F, NF, SIZE, OFF);  \
5037                 }                                                              \
5038         } while (0)
5039
5040 #define SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD(S, NS, F, NF, TF)                 \
5041         SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(                         \
5042                 S, NS, F, NF, BPF_FIELD_SIZEOF(NS, NF), 0, TF)
5043
5044 static u32 sock_addr_convert_ctx_access(enum bpf_access_type type,
5045                                         const struct bpf_insn *si,
5046                                         struct bpf_insn *insn_buf,
5047                                         struct bpf_prog *prog, u32 *target_size)
5048 {
5049         struct bpf_insn *insn = insn_buf;
5050         int off;
5051
5052         switch (si->off) {
5053         case offsetof(struct bpf_sock_addr, user_family):
5054                 SOCK_ADDR_LOAD_NESTED_FIELD(struct bpf_sock_addr_kern,
5055                                             struct sockaddr, uaddr, sa_family);
5056                 break;
5057
5058         case offsetof(struct bpf_sock_addr, user_ip4):
5059                 SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(
5060                         struct bpf_sock_addr_kern, struct sockaddr_in, uaddr,
5061                         sin_addr, BPF_SIZE(si->code), 0, tmp_reg);
5062                 break;
5063
5064         case bpf_ctx_range_till(struct bpf_sock_addr, user_ip6[0], user_ip6[3]):
5065                 off = si->off;
5066                 off -= offsetof(struct bpf_sock_addr, user_ip6[0]);
5067                 SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(
5068                         struct bpf_sock_addr_kern, struct sockaddr_in6, uaddr,
5069                         sin6_addr.s6_addr32[0], BPF_SIZE(si->code), off,
5070                         tmp_reg);
5071                 break;
5072
5073         case offsetof(struct bpf_sock_addr, user_port):
5074                 /* To get port we need to know sa_family first and then treat
5075                  * sockaddr as either sockaddr_in or sockaddr_in6.
5076                  * Though we can simplify since port field has same offset and
5077                  * size in both structures.
5078                  * Here we check this invariant and use just one of the
5079                  * structures if it's true.
5080                  */
5081                 BUILD_BUG_ON(offsetof(struct sockaddr_in, sin_port) !=
5082                              offsetof(struct sockaddr_in6, sin6_port));
5083                 BUILD_BUG_ON(FIELD_SIZEOF(struct sockaddr_in, sin_port) !=
5084                              FIELD_SIZEOF(struct sockaddr_in6, sin6_port));
5085                 SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD(struct bpf_sock_addr_kern,
5086                                                      struct sockaddr_in6, uaddr,
5087                                                      sin6_port, tmp_reg);
5088                 break;
5089
5090         case offsetof(struct bpf_sock_addr, family):
5091                 SOCK_ADDR_LOAD_NESTED_FIELD(struct bpf_sock_addr_kern,
5092                                             struct sock, sk, sk_family);
5093                 break;
5094
5095         case offsetof(struct bpf_sock_addr, type):
5096                 SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF(
5097                         struct bpf_sock_addr_kern, struct sock, sk,
5098                         __sk_flags_offset, BPF_W, 0);
5099                 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, SK_FL_TYPE_MASK);
5100                 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, SK_FL_TYPE_SHIFT);
5101                 break;
5102
5103         case offsetof(struct bpf_sock_addr, protocol):
5104                 SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF(
5105                         struct bpf_sock_addr_kern, struct sock, sk,
5106                         __sk_flags_offset, BPF_W, 0);
5107                 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, SK_FL_PROTO_MASK);
5108                 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg,
5109                                         SK_FL_PROTO_SHIFT);
5110                 break;
5111         }
5112
5113         return insn - insn_buf;
5114 }
5115
5116 static u32 sock_ops_convert_ctx_access(enum bpf_access_type type,
5117                                        const struct bpf_insn *si,
5118                                        struct bpf_insn *insn_buf,
5119                                        struct bpf_prog *prog,
5120                                        u32 *target_size)
5121 {
5122         struct bpf_insn *insn = insn_buf;
5123         int off;
5124
5125         switch (si->off) {
5126         case offsetof(struct bpf_sock_ops, op) ...
5127              offsetof(struct bpf_sock_ops, replylong[3]):
5128                 BUILD_BUG_ON(FIELD_SIZEOF(struct bpf_sock_ops, op) !=
5129                              FIELD_SIZEOF(struct bpf_sock_ops_kern, op));
5130                 BUILD_BUG_ON(FIELD_SIZEOF(struct bpf_sock_ops, reply) !=
5131                              FIELD_SIZEOF(struct bpf_sock_ops_kern, reply));
5132                 BUILD_BUG_ON(FIELD_SIZEOF(struct bpf_sock_ops, replylong) !=
5133                              FIELD_SIZEOF(struct bpf_sock_ops_kern, replylong));
5134                 off = si->off;
5135                 off -= offsetof(struct bpf_sock_ops, op);
5136                 off += offsetof(struct bpf_sock_ops_kern, op);
5137                 if (type == BPF_WRITE)
5138                         *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
5139                                               off);
5140                 else
5141                         *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
5142                                               off);
5143                 break;
5144
5145         case offsetof(struct bpf_sock_ops, family):
5146                 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_family) != 2);
5147
5148                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
5149                                               struct bpf_sock_ops_kern, sk),
5150                                       si->dst_reg, si->src_reg,
5151                                       offsetof(struct bpf_sock_ops_kern, sk));
5152                 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
5153                                       offsetof(struct sock_common, skc_family));
5154                 break;
5155
5156         case offsetof(struct bpf_sock_ops, remote_ip4):
5157                 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_daddr) != 4);
5158
5159                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
5160                                                 struct bpf_sock_ops_kern, sk),
5161                                       si->dst_reg, si->src_reg,
5162                                       offsetof(struct bpf_sock_ops_kern, sk));
5163                 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
5164                                       offsetof(struct sock_common, skc_daddr));
5165                 break;
5166
5167         case offsetof(struct bpf_sock_ops, local_ip4):
5168                 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_rcv_saddr) != 4);
5169
5170                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
5171                                               struct bpf_sock_ops_kern, sk),
5172                                       si->dst_reg, si->src_reg,
5173                                       offsetof(struct bpf_sock_ops_kern, sk));
5174                 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
5175                                       offsetof(struct sock_common,
5176                                                skc_rcv_saddr));
5177                 break;
5178
5179         case offsetof(struct bpf_sock_ops, remote_ip6[0]) ...
5180              offsetof(struct bpf_sock_ops, remote_ip6[3]):
5181 #if IS_ENABLED(CONFIG_IPV6)
5182                 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common,
5183                                           skc_v6_daddr.s6_addr32[0]) != 4);
5184
5185                 off = si->off;
5186                 off -= offsetof(struct bpf_sock_ops, remote_ip6[0]);
5187                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
5188                                                 struct bpf_sock_ops_kern, sk),
5189                                       si->dst_reg, si->src_reg,
5190                                       offsetof(struct bpf_sock_ops_kern, sk));
5191                 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
5192                                       offsetof(struct sock_common,
5193                                                skc_v6_daddr.s6_addr32[0]) +
5194                                       off);
5195 #else
5196                 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
5197 #endif
5198                 break;
5199
5200         case offsetof(struct bpf_sock_ops, local_ip6[0]) ...
5201              offsetof(struct bpf_sock_ops, local_ip6[3]):
5202 #if IS_ENABLED(CONFIG_IPV6)
5203                 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common,
5204                                           skc_v6_rcv_saddr.s6_addr32[0]) != 4);
5205
5206                 off = si->off;
5207                 off -= offsetof(struct bpf_sock_ops, local_ip6[0]);
5208                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
5209                                                 struct bpf_sock_ops_kern, sk),
5210                                       si->dst_reg, si->src_reg,
5211                                       offsetof(struct bpf_sock_ops_kern, sk));
5212                 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
5213                                       offsetof(struct sock_common,
5214                                                skc_v6_rcv_saddr.s6_addr32[0]) +
5215                                       off);
5216 #else
5217                 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
5218 #endif
5219                 break;
5220
5221         case offsetof(struct bpf_sock_ops, remote_port):
5222                 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_dport) != 2);
5223
5224                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
5225                                                 struct bpf_sock_ops_kern, sk),
5226                                       si->dst_reg, si->src_reg,
5227                                       offsetof(struct bpf_sock_ops_kern, sk));
5228                 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
5229                                       offsetof(struct sock_common, skc_dport));
5230 #ifndef __BIG_ENDIAN_BITFIELD
5231                 *insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16);
5232 #endif
5233                 break;
5234
5235         case offsetof(struct bpf_sock_ops, local_port):
5236                 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_num) != 2);
5237
5238                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
5239                                                 struct bpf_sock_ops_kern, sk),
5240                                       si->dst_reg, si->src_reg,
5241                                       offsetof(struct bpf_sock_ops_kern, sk));
5242                 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
5243                                       offsetof(struct sock_common, skc_num));
5244                 break;
5245
5246         case offsetof(struct bpf_sock_ops, is_fullsock):
5247                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
5248                                                 struct bpf_sock_ops_kern,
5249                                                 is_fullsock),
5250                                       si->dst_reg, si->src_reg,
5251                                       offsetof(struct bpf_sock_ops_kern,
5252                                                is_fullsock));
5253                 break;
5254
5255         case offsetof(struct bpf_sock_ops, state):
5256                 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_state) != 1);
5257
5258                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
5259                                                 struct bpf_sock_ops_kern, sk),
5260                                       si->dst_reg, si->src_reg,
5261                                       offsetof(struct bpf_sock_ops_kern, sk));
5262                 *insn++ = BPF_LDX_MEM(BPF_B, si->dst_reg, si->dst_reg,
5263                                       offsetof(struct sock_common, skc_state));
5264                 break;
5265
5266         case offsetof(struct bpf_sock_ops, rtt_min):
5267                 BUILD_BUG_ON(FIELD_SIZEOF(struct tcp_sock, rtt_min) !=
5268                              sizeof(struct minmax));
5269                 BUILD_BUG_ON(sizeof(struct minmax) <
5270                              sizeof(struct minmax_sample));
5271
5272                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
5273                                                 struct bpf_sock_ops_kern, sk),
5274                                       si->dst_reg, si->src_reg,
5275                                       offsetof(struct bpf_sock_ops_kern, sk));
5276                 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
5277                                       offsetof(struct tcp_sock, rtt_min) +
5278                                       FIELD_SIZEOF(struct minmax_sample, t));
5279                 break;
5280
5281 /* Helper macro for adding read access to tcp_sock or sock fields. */
5282 #define SOCK_OPS_GET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ)                         \
5283         do {                                                                  \
5284                 BUILD_BUG_ON(FIELD_SIZEOF(OBJ, OBJ_FIELD) >                   \
5285                              FIELD_SIZEOF(struct bpf_sock_ops, BPF_FIELD));   \
5286                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(                       \
5287                                                 struct bpf_sock_ops_kern,     \
5288                                                 is_fullsock),                 \
5289                                       si->dst_reg, si->src_reg,               \
5290                                       offsetof(struct bpf_sock_ops_kern,      \
5291                                                is_fullsock));                 \
5292                 *insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 2);            \
5293                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(                       \
5294                                                 struct bpf_sock_ops_kern, sk),\
5295                                       si->dst_reg, si->src_reg,               \
5296                                       offsetof(struct bpf_sock_ops_kern, sk));\
5297                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(OBJ,                   \
5298                                                        OBJ_FIELD),            \
5299                                       si->dst_reg, si->dst_reg,               \
5300                                       offsetof(OBJ, OBJ_FIELD));              \
5301         } while (0)
5302
5303 /* Helper macro for adding write access to tcp_sock or sock fields.
5304  * The macro is called with two registers, dst_reg which contains a pointer
5305  * to ctx (context) and src_reg which contains the value that should be
5306  * stored. However, we need an additional register since we cannot overwrite
5307  * dst_reg because it may be used later in the program.
5308  * Instead we "borrow" one of the other register. We first save its value
5309  * into a new (temp) field in bpf_sock_ops_kern, use it, and then restore
5310  * it at the end of the macro.
5311  */
5312 #define SOCK_OPS_SET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ)                         \
5313         do {                                                                  \
5314                 int reg = BPF_REG_9;                                          \
5315                 BUILD_BUG_ON(FIELD_SIZEOF(OBJ, OBJ_FIELD) >                   \
5316                              FIELD_SIZEOF(struct bpf_sock_ops, BPF_FIELD));   \
5317                 if (si->dst_reg == reg || si->src_reg == reg)                 \
5318                         reg--;                                                \
5319                 if (si->dst_reg == reg || si->src_reg == reg)                 \
5320                         reg--;                                                \
5321                 *insn++ = BPF_STX_MEM(BPF_DW, si->dst_reg, reg,               \
5322                                       offsetof(struct bpf_sock_ops_kern,      \
5323                                                temp));                        \
5324                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(                       \
5325                                                 struct bpf_sock_ops_kern,     \
5326                                                 is_fullsock),                 \
5327                                       reg, si->dst_reg,                       \
5328                                       offsetof(struct bpf_sock_ops_kern,      \
5329                                                is_fullsock));                 \
5330                 *insn++ = BPF_JMP_IMM(BPF_JEQ, reg, 0, 2);                    \
5331                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(                       \
5332                                                 struct bpf_sock_ops_kern, sk),\
5333                                       reg, si->dst_reg,                       \
5334                                       offsetof(struct bpf_sock_ops_kern, sk));\
5335                 *insn++ = BPF_STX_MEM(BPF_FIELD_SIZEOF(OBJ, OBJ_FIELD),       \
5336                                       reg, si->src_reg,                       \
5337                                       offsetof(OBJ, OBJ_FIELD));              \
5338                 *insn++ = BPF_LDX_MEM(BPF_DW, reg, si->dst_reg,               \
5339                                       offsetof(struct bpf_sock_ops_kern,      \
5340                                                temp));                        \
5341         } while (0)
5342
5343 #define SOCK_OPS_GET_OR_SET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ, TYPE)            \
5344         do {                                                                  \
5345                 if (TYPE == BPF_WRITE)                                        \
5346                         SOCK_OPS_SET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ);        \
5347                 else                                                          \
5348                         SOCK_OPS_GET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ);        \
5349         } while (0)
5350
5351         case offsetof(struct bpf_sock_ops, snd_cwnd):
5352                 SOCK_OPS_GET_FIELD(snd_cwnd, snd_cwnd, struct tcp_sock);
5353                 break;
5354
5355         case offsetof(struct bpf_sock_ops, srtt_us):
5356                 SOCK_OPS_GET_FIELD(srtt_us, srtt_us, struct tcp_sock);
5357                 break;
5358
5359         case offsetof(struct bpf_sock_ops, bpf_sock_ops_cb_flags):
5360                 SOCK_OPS_GET_FIELD(bpf_sock_ops_cb_flags, bpf_sock_ops_cb_flags,
5361                                    struct tcp_sock);
5362                 break;
5363
5364         case offsetof(struct bpf_sock_ops, snd_ssthresh):
5365                 SOCK_OPS_GET_FIELD(snd_ssthresh, snd_ssthresh, struct tcp_sock);
5366                 break;
5367
5368         case offsetof(struct bpf_sock_ops, rcv_nxt):
5369                 SOCK_OPS_GET_FIELD(rcv_nxt, rcv_nxt, struct tcp_sock);
5370                 break;
5371
5372         case offsetof(struct bpf_sock_ops, snd_nxt):
5373                 SOCK_OPS_GET_FIELD(snd_nxt, snd_nxt, struct tcp_sock);
5374                 break;
5375
5376         case offsetof(struct bpf_sock_ops, snd_una):
5377                 SOCK_OPS_GET_FIELD(snd_una, snd_una, struct tcp_sock);
5378                 break;
5379
5380         case offsetof(struct bpf_sock_ops, mss_cache):
5381                 SOCK_OPS_GET_FIELD(mss_cache, mss_cache, struct tcp_sock);
5382                 break;
5383
5384         case offsetof(struct bpf_sock_ops, ecn_flags):
5385                 SOCK_OPS_GET_FIELD(ecn_flags, ecn_flags, struct tcp_sock);
5386                 break;
5387
5388         case offsetof(struct bpf_sock_ops, rate_delivered):
5389                 SOCK_OPS_GET_FIELD(rate_delivered, rate_delivered,
5390                                    struct tcp_sock);
5391                 break;
5392
5393         case offsetof(struct bpf_sock_ops, rate_interval_us):
5394                 SOCK_OPS_GET_FIELD(rate_interval_us, rate_interval_us,
5395                                    struct tcp_sock);
5396                 break;
5397
5398         case offsetof(struct bpf_sock_ops, packets_out):
5399                 SOCK_OPS_GET_FIELD(packets_out, packets_out, struct tcp_sock);
5400                 break;
5401
5402         case offsetof(struct bpf_sock_ops, retrans_out):
5403                 SOCK_OPS_GET_FIELD(retrans_out, retrans_out, struct tcp_sock);
5404                 break;
5405
5406         case offsetof(struct bpf_sock_ops, total_retrans):
5407                 SOCK_OPS_GET_FIELD(total_retrans, total_retrans,
5408                                    struct tcp_sock);
5409                 break;
5410
5411         case offsetof(struct bpf_sock_ops, segs_in):
5412                 SOCK_OPS_GET_FIELD(segs_in, segs_in, struct tcp_sock);
5413                 break;
5414
5415         case offsetof(struct bpf_sock_ops, data_segs_in):
5416                 SOCK_OPS_GET_FIELD(data_segs_in, data_segs_in, struct tcp_sock);
5417                 break;
5418
5419         case offsetof(struct bpf_sock_ops, segs_out):
5420                 SOCK_OPS_GET_FIELD(segs_out, segs_out, struct tcp_sock);
5421                 break;
5422
5423         case offsetof(struct bpf_sock_ops, data_segs_out):
5424                 SOCK_OPS_GET_FIELD(data_segs_out, data_segs_out,
5425                                    struct tcp_sock);
5426                 break;
5427
5428         case offsetof(struct bpf_sock_ops, lost_out):
5429                 SOCK_OPS_GET_FIELD(lost_out, lost_out, struct tcp_sock);
5430                 break;
5431
5432         case offsetof(struct bpf_sock_ops, sacked_out):
5433                 SOCK_OPS_GET_FIELD(sacked_out, sacked_out, struct tcp_sock);
5434                 break;
5435
5436         case offsetof(struct bpf_sock_ops, sk_txhash):
5437                 SOCK_OPS_GET_OR_SET_FIELD(sk_txhash, sk_txhash,
5438                                           struct sock, type);
5439                 break;
5440
5441         case offsetof(struct bpf_sock_ops, bytes_received):
5442                 SOCK_OPS_GET_FIELD(bytes_received, bytes_received,
5443                                    struct tcp_sock);
5444                 break;
5445
5446         case offsetof(struct bpf_sock_ops, bytes_acked):
5447                 SOCK_OPS_GET_FIELD(bytes_acked, bytes_acked, struct tcp_sock);
5448                 break;
5449
5450         }
5451         return insn - insn_buf;
5452 }
5453
5454 static u32 sk_skb_convert_ctx_access(enum bpf_access_type type,
5455                                      const struct bpf_insn *si,
5456                                      struct bpf_insn *insn_buf,
5457                                      struct bpf_prog *prog, u32 *target_size)
5458 {
5459         struct bpf_insn *insn = insn_buf;
5460         int off;
5461
5462         switch (si->off) {
5463         case offsetof(struct __sk_buff, data_end):
5464                 off  = si->off;
5465                 off -= offsetof(struct __sk_buff, data_end);
5466                 off += offsetof(struct sk_buff, cb);
5467                 off += offsetof(struct tcp_skb_cb, bpf.data_end);
5468                 *insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg,
5469                                       si->src_reg, off);
5470                 break;
5471         default:
5472                 return bpf_convert_ctx_access(type, si, insn_buf, prog,
5473                                               target_size);
5474         }
5475
5476         return insn - insn_buf;
5477 }
5478
5479 static u32 sk_msg_convert_ctx_access(enum bpf_access_type type,
5480                                      const struct bpf_insn *si,
5481                                      struct bpf_insn *insn_buf,
5482                                      struct bpf_prog *prog, u32 *target_size)
5483 {
5484         struct bpf_insn *insn = insn_buf;
5485
5486         switch (si->off) {
5487         case offsetof(struct sk_msg_md, data):
5488                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_msg_buff, data),
5489                                       si->dst_reg, si->src_reg,
5490                                       offsetof(struct sk_msg_buff, data));
5491                 break;
5492         case offsetof(struct sk_msg_md, data_end):
5493                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_msg_buff, data_end),
5494                                       si->dst_reg, si->src_reg,
5495                                       offsetof(struct sk_msg_buff, data_end));
5496                 break;
5497         }
5498
5499         return insn - insn_buf;
5500 }
5501
5502 const struct bpf_verifier_ops sk_filter_verifier_ops = {
5503         .get_func_proto         = sk_filter_func_proto,
5504         .is_valid_access        = sk_filter_is_valid_access,
5505         .convert_ctx_access     = bpf_convert_ctx_access,
5506 };
5507
5508 const struct bpf_prog_ops sk_filter_prog_ops = {
5509         .test_run               = bpf_prog_test_run_skb,
5510 };
5511
5512 const struct bpf_verifier_ops tc_cls_act_verifier_ops = {
5513         .get_func_proto         = tc_cls_act_func_proto,
5514         .is_valid_access        = tc_cls_act_is_valid_access,
5515         .convert_ctx_access     = tc_cls_act_convert_ctx_access,
5516         .gen_prologue           = tc_cls_act_prologue,
5517 };
5518
5519 const struct bpf_prog_ops tc_cls_act_prog_ops = {
5520         .test_run               = bpf_prog_test_run_skb,
5521 };
5522
5523 const struct bpf_verifier_ops xdp_verifier_ops = {
5524         .get_func_proto         = xdp_func_proto,
5525         .is_valid_access        = xdp_is_valid_access,
5526         .convert_ctx_access     = xdp_convert_ctx_access,
5527 };
5528
5529 const struct bpf_prog_ops xdp_prog_ops = {
5530         .test_run               = bpf_prog_test_run_xdp,
5531 };
5532
5533 const struct bpf_verifier_ops cg_skb_verifier_ops = {
5534         .get_func_proto         = sk_filter_func_proto,
5535         .is_valid_access        = sk_filter_is_valid_access,
5536         .convert_ctx_access     = bpf_convert_ctx_access,
5537 };
5538
5539 const struct bpf_prog_ops cg_skb_prog_ops = {
5540         .test_run               = bpf_prog_test_run_skb,
5541 };
5542
5543 const struct bpf_verifier_ops lwt_inout_verifier_ops = {
5544         .get_func_proto         = lwt_inout_func_proto,
5545         .is_valid_access        = lwt_is_valid_access,
5546         .convert_ctx_access     = bpf_convert_ctx_access,
5547 };
5548
5549 const struct bpf_prog_ops lwt_inout_prog_ops = {
5550         .test_run               = bpf_prog_test_run_skb,
5551 };
5552
5553 const struct bpf_verifier_ops lwt_xmit_verifier_ops = {
5554         .get_func_proto         = lwt_xmit_func_proto,
5555         .is_valid_access        = lwt_is_valid_access,
5556         .convert_ctx_access     = bpf_convert_ctx_access,
5557         .gen_prologue           = tc_cls_act_prologue,
5558 };
5559
5560 const struct bpf_prog_ops lwt_xmit_prog_ops = {
5561         .test_run               = bpf_prog_test_run_skb,
5562 };
5563
5564 const struct bpf_verifier_ops cg_sock_verifier_ops = {
5565         .get_func_proto         = sock_filter_func_proto,
5566         .is_valid_access        = sock_filter_is_valid_access,
5567         .convert_ctx_access     = sock_filter_convert_ctx_access,
5568 };
5569
5570 const struct bpf_prog_ops cg_sock_prog_ops = {
5571 };
5572
5573 const struct bpf_verifier_ops cg_sock_addr_verifier_ops = {
5574         .get_func_proto         = sock_addr_func_proto,
5575         .is_valid_access        = sock_addr_is_valid_access,
5576         .convert_ctx_access     = sock_addr_convert_ctx_access,
5577 };
5578
5579 const struct bpf_prog_ops cg_sock_addr_prog_ops = {
5580 };
5581
5582 const struct bpf_verifier_ops sock_ops_verifier_ops = {
5583         .get_func_proto         = sock_ops_func_proto,
5584         .is_valid_access        = sock_ops_is_valid_access,
5585         .convert_ctx_access     = sock_ops_convert_ctx_access,
5586 };
5587
5588 const struct bpf_prog_ops sock_ops_prog_ops = {
5589 };
5590
5591 const struct bpf_verifier_ops sk_skb_verifier_ops = {
5592         .get_func_proto         = sk_skb_func_proto,
5593         .is_valid_access        = sk_skb_is_valid_access,
5594         .convert_ctx_access     = sk_skb_convert_ctx_access,
5595         .gen_prologue           = sk_skb_prologue,
5596 };
5597
5598 const struct bpf_prog_ops sk_skb_prog_ops = {
5599 };
5600
5601 const struct bpf_verifier_ops sk_msg_verifier_ops = {
5602         .get_func_proto         = sk_msg_func_proto,
5603         .is_valid_access        = sk_msg_is_valid_access,
5604         .convert_ctx_access     = sk_msg_convert_ctx_access,
5605 };
5606
5607 const struct bpf_prog_ops sk_msg_prog_ops = {
5608 };
5609
5610 int sk_detach_filter(struct sock *sk)
5611 {
5612         int ret = -ENOENT;
5613         struct sk_filter *filter;
5614
5615         if (sock_flag(sk, SOCK_FILTER_LOCKED))
5616                 return -EPERM;
5617
5618         filter = rcu_dereference_protected(sk->sk_filter,
5619                                            lockdep_sock_is_held(sk));
5620         if (filter) {
5621                 RCU_INIT_POINTER(sk->sk_filter, NULL);
5622                 sk_filter_uncharge(sk, filter);
5623                 ret = 0;
5624         }
5625
5626         return ret;
5627 }
5628 EXPORT_SYMBOL_GPL(sk_detach_filter);
5629
5630 int sk_get_filter(struct sock *sk, struct sock_filter __user *ubuf,
5631                   unsigned int len)
5632 {
5633         struct sock_fprog_kern *fprog;
5634         struct sk_filter *filter;
5635         int ret = 0;
5636
5637         lock_sock(sk);
5638         filter = rcu_dereference_protected(sk->sk_filter,
5639                                            lockdep_sock_is_held(sk));
5640         if (!filter)
5641                 goto out;
5642
5643         /* We're copying the filter that has been originally attached,
5644          * so no conversion/decode needed anymore. eBPF programs that
5645          * have no original program cannot be dumped through this.
5646          */
5647         ret = -EACCES;
5648         fprog = filter->prog->orig_prog;
5649         if (!fprog)
5650                 goto out;
5651
5652         ret = fprog->len;
5653         if (!len)
5654                 /* User space only enquires number of filter blocks. */
5655                 goto out;
5656
5657         ret = -EINVAL;
5658         if (len < fprog->len)
5659                 goto out;
5660
5661         ret = -EFAULT;
5662         if (copy_to_user(ubuf, fprog->filter, bpf_classic_proglen(fprog)))
5663                 goto out;
5664
5665         /* Instead of bytes, the API requests to return the number
5666          * of filter blocks.
5667          */
5668         ret = fprog->len;
5669 out:
5670         release_sock(sk);
5671         return ret;
5672 }