2 * Linux Socket Filter - Kernel level socket filtering
4 * Based on the design of the Berkeley Packet Filter. The new
5 * internal format has been designed by PLUMgrid:
7 * Copyright (c) 2011 - 2014 PLUMgrid, http://plumgrid.com
11 * Jay Schulist <jschlst@samba.org>
12 * Alexei Starovoitov <ast@plumgrid.com>
13 * Daniel Borkmann <dborkman@redhat.com>
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.
20 * Andi Kleen - Fix a few bad bugs and races.
21 * Kris Katterjohn - Added many additional checks in bpf_check_classic()
24 #include <linux/module.h>
25 #include <linux/types.h>
27 #include <linux/fcntl.h>
28 #include <linux/socket.h>
29 #include <linux/sock_diag.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>
37 #include <net/protocol.h>
38 #include <net/netlink.h>
39 #include <linux/skbuff.h>
41 #include <net/flow_dissector.h>
42 #include <linux/errno.h>
43 #include <linux/timer.h>
44 #include <linux/uaccess.h>
45 #include <asm/unaligned.h>
46 #include <linux/filter.h>
47 #include <linux/ratelimit.h>
48 #include <linux/seccomp.h>
49 #include <linux/if_vlan.h>
50 #include <linux/bpf.h>
51 #include <net/sch_generic.h>
52 #include <net/cls_cgroup.h>
53 #include <net/dst_metadata.h>
55 #include <net/sock_reuseport.h>
56 #include <net/busy_poll.h>
58 #include <linux/bpf_trace.h>
61 * sk_filter_trim_cap - run a packet through a socket filter
62 * @sk: sock associated with &sk_buff
63 * @skb: buffer to filter
64 * @cap: limit on how short the eBPF program may trim the packet
66 * Run the eBPF program and then cut skb->data to correct size returned by
67 * the program. If pkt_len is 0 we toss packet. If skb->len is smaller
68 * than pkt_len we keep whole skb->data. This is the socket level
69 * wrapper to BPF_PROG_RUN. It returns 0 if the packet should
70 * be accepted or -EPERM if the packet should be tossed.
73 int sk_filter_trim_cap(struct sock *sk, struct sk_buff *skb, unsigned int cap)
76 struct sk_filter *filter;
79 * If the skb was allocated from pfmemalloc reserves, only
80 * allow SOCK_MEMALLOC sockets to use it as this socket is
83 if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC)) {
84 NET_INC_STATS(sock_net(sk), LINUX_MIB_PFMEMALLOCDROP);
87 err = BPF_CGROUP_RUN_PROG_INET_INGRESS(sk, skb);
91 err = security_sock_rcv_skb(sk, skb);
96 filter = rcu_dereference(sk->sk_filter);
98 struct sock *save_sk = skb->sk;
102 pkt_len = bpf_prog_run_save_cb(filter->prog, skb);
104 err = pkt_len ? pskb_trim(skb, max(cap, pkt_len)) : -EPERM;
110 EXPORT_SYMBOL(sk_filter_trim_cap);
112 BPF_CALL_1(__skb_get_pay_offset, struct sk_buff *, skb)
114 return skb_get_poff(skb);
117 BPF_CALL_3(__skb_get_nlattr, struct sk_buff *, skb, u32, a, u32, x)
121 if (skb_is_nonlinear(skb))
124 if (skb->len < sizeof(struct nlattr))
127 if (a > skb->len - sizeof(struct nlattr))
130 nla = nla_find((struct nlattr *) &skb->data[a], skb->len - a, x);
132 return (void *) nla - (void *) skb->data;
137 BPF_CALL_3(__skb_get_nlattr_nest, struct sk_buff *, skb, u32, a, u32, x)
141 if (skb_is_nonlinear(skb))
144 if (skb->len < sizeof(struct nlattr))
147 if (a > skb->len - sizeof(struct nlattr))
150 nla = (struct nlattr *) &skb->data[a];
151 if (nla->nla_len > skb->len - a)
154 nla = nla_find_nested(nla, x);
156 return (void *) nla - (void *) skb->data;
161 BPF_CALL_0(__get_raw_cpu_id)
163 return raw_smp_processor_id();
166 static const struct bpf_func_proto bpf_get_raw_smp_processor_id_proto = {
167 .func = __get_raw_cpu_id,
169 .ret_type = RET_INTEGER,
172 static u32 convert_skb_access(int skb_field, int dst_reg, int src_reg,
173 struct bpf_insn *insn_buf)
175 struct bpf_insn *insn = insn_buf;
179 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, mark) != 4);
181 *insn++ = BPF_LDX_MEM(BPF_W, dst_reg, src_reg,
182 offsetof(struct sk_buff, mark));
186 *insn++ = BPF_LDX_MEM(BPF_B, dst_reg, src_reg, PKT_TYPE_OFFSET());
187 *insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg, PKT_TYPE_MAX);
188 #ifdef __BIG_ENDIAN_BITFIELD
189 *insn++ = BPF_ALU32_IMM(BPF_RSH, dst_reg, 5);
194 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, queue_mapping) != 2);
196 *insn++ = BPF_LDX_MEM(BPF_H, dst_reg, src_reg,
197 offsetof(struct sk_buff, queue_mapping));
200 case SKF_AD_VLAN_TAG:
201 case SKF_AD_VLAN_TAG_PRESENT:
202 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, vlan_tci) != 2);
203 BUILD_BUG_ON(VLAN_TAG_PRESENT != 0x1000);
205 /* dst_reg = *(u16 *) (src_reg + offsetof(vlan_tci)) */
206 *insn++ = BPF_LDX_MEM(BPF_H, dst_reg, src_reg,
207 offsetof(struct sk_buff, vlan_tci));
208 if (skb_field == SKF_AD_VLAN_TAG) {
209 *insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg,
213 *insn++ = BPF_ALU32_IMM(BPF_RSH, dst_reg, 12);
215 *insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg, 1);
220 return insn - insn_buf;
223 static bool convert_bpf_extensions(struct sock_filter *fp,
224 struct bpf_insn **insnp)
226 struct bpf_insn *insn = *insnp;
230 case SKF_AD_OFF + SKF_AD_PROTOCOL:
231 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, protocol) != 2);
233 /* A = *(u16 *) (CTX + offsetof(protocol)) */
234 *insn++ = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_CTX,
235 offsetof(struct sk_buff, protocol));
236 /* A = ntohs(A) [emitting a nop or swap16] */
237 *insn = BPF_ENDIAN(BPF_FROM_BE, BPF_REG_A, 16);
240 case SKF_AD_OFF + SKF_AD_PKTTYPE:
241 cnt = convert_skb_access(SKF_AD_PKTTYPE, BPF_REG_A, BPF_REG_CTX, insn);
245 case SKF_AD_OFF + SKF_AD_IFINDEX:
246 case SKF_AD_OFF + SKF_AD_HATYPE:
247 BUILD_BUG_ON(FIELD_SIZEOF(struct net_device, ifindex) != 4);
248 BUILD_BUG_ON(FIELD_SIZEOF(struct net_device, type) != 2);
250 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev),
251 BPF_REG_TMP, BPF_REG_CTX,
252 offsetof(struct sk_buff, dev));
253 /* if (tmp != 0) goto pc + 1 */
254 *insn++ = BPF_JMP_IMM(BPF_JNE, BPF_REG_TMP, 0, 1);
255 *insn++ = BPF_EXIT_INSN();
256 if (fp->k == SKF_AD_OFF + SKF_AD_IFINDEX)
257 *insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_TMP,
258 offsetof(struct net_device, ifindex));
260 *insn = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_TMP,
261 offsetof(struct net_device, type));
264 case SKF_AD_OFF + SKF_AD_MARK:
265 cnt = convert_skb_access(SKF_AD_MARK, BPF_REG_A, BPF_REG_CTX, insn);
269 case SKF_AD_OFF + SKF_AD_RXHASH:
270 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, hash) != 4);
272 *insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_CTX,
273 offsetof(struct sk_buff, hash));
276 case SKF_AD_OFF + SKF_AD_QUEUE:
277 cnt = convert_skb_access(SKF_AD_QUEUE, BPF_REG_A, BPF_REG_CTX, insn);
281 case SKF_AD_OFF + SKF_AD_VLAN_TAG:
282 cnt = convert_skb_access(SKF_AD_VLAN_TAG,
283 BPF_REG_A, BPF_REG_CTX, insn);
287 case SKF_AD_OFF + SKF_AD_VLAN_TAG_PRESENT:
288 cnt = convert_skb_access(SKF_AD_VLAN_TAG_PRESENT,
289 BPF_REG_A, BPF_REG_CTX, insn);
293 case SKF_AD_OFF + SKF_AD_VLAN_TPID:
294 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, vlan_proto) != 2);
296 /* A = *(u16 *) (CTX + offsetof(vlan_proto)) */
297 *insn++ = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_CTX,
298 offsetof(struct sk_buff, vlan_proto));
299 /* A = ntohs(A) [emitting a nop or swap16] */
300 *insn = BPF_ENDIAN(BPF_FROM_BE, BPF_REG_A, 16);
303 case SKF_AD_OFF + SKF_AD_PAY_OFFSET:
304 case SKF_AD_OFF + SKF_AD_NLATTR:
305 case SKF_AD_OFF + SKF_AD_NLATTR_NEST:
306 case SKF_AD_OFF + SKF_AD_CPU:
307 case SKF_AD_OFF + SKF_AD_RANDOM:
309 *insn++ = BPF_MOV64_REG(BPF_REG_ARG1, BPF_REG_CTX);
311 *insn++ = BPF_MOV64_REG(BPF_REG_ARG2, BPF_REG_A);
313 *insn++ = BPF_MOV64_REG(BPF_REG_ARG3, BPF_REG_X);
314 /* Emit call(arg1=CTX, arg2=A, arg3=X) */
316 case SKF_AD_OFF + SKF_AD_PAY_OFFSET:
317 *insn = BPF_EMIT_CALL(__skb_get_pay_offset);
319 case SKF_AD_OFF + SKF_AD_NLATTR:
320 *insn = BPF_EMIT_CALL(__skb_get_nlattr);
322 case SKF_AD_OFF + SKF_AD_NLATTR_NEST:
323 *insn = BPF_EMIT_CALL(__skb_get_nlattr_nest);
325 case SKF_AD_OFF + SKF_AD_CPU:
326 *insn = BPF_EMIT_CALL(__get_raw_cpu_id);
328 case SKF_AD_OFF + SKF_AD_RANDOM:
329 *insn = BPF_EMIT_CALL(bpf_user_rnd_u32);
330 bpf_user_rnd_init_once();
335 case SKF_AD_OFF + SKF_AD_ALU_XOR_X:
337 *insn = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_X);
341 /* This is just a dummy call to avoid letting the compiler
342 * evict __bpf_call_base() as an optimization. Placed here
343 * where no-one bothers.
345 BUG_ON(__bpf_call_base(0, 0, 0, 0, 0) != 0);
354 * bpf_convert_filter - convert filter program
355 * @prog: the user passed filter program
356 * @len: the length of the user passed filter program
357 * @new_prog: allocated 'struct bpf_prog' or NULL
358 * @new_len: pointer to store length of converted program
360 * Remap 'sock_filter' style classic BPF (cBPF) instruction set to 'bpf_insn'
361 * style extended BPF (eBPF).
362 * Conversion workflow:
364 * 1) First pass for calculating the new program length:
365 * bpf_convert_filter(old_prog, old_len, NULL, &new_len)
367 * 2) 2nd pass to remap in two passes: 1st pass finds new
368 * jump offsets, 2nd pass remapping:
369 * bpf_convert_filter(old_prog, old_len, new_prog, &new_len);
371 static int bpf_convert_filter(struct sock_filter *prog, int len,
372 struct bpf_prog *new_prog, int *new_len)
374 int new_flen = 0, pass = 0, target, i, stack_off;
375 struct bpf_insn *new_insn, *first_insn = NULL;
376 struct sock_filter *fp;
380 BUILD_BUG_ON(BPF_MEMWORDS * sizeof(u32) > MAX_BPF_STACK);
381 BUILD_BUG_ON(BPF_REG_FP + 1 != MAX_BPF_REG);
383 if (len <= 0 || len > BPF_MAXINSNS)
387 first_insn = new_prog->insnsi;
388 addrs = kcalloc(len, sizeof(*addrs),
389 GFP_KERNEL | __GFP_NOWARN);
395 new_insn = first_insn;
398 /* Classic BPF related prologue emission. */
400 /* Classic BPF expects A and X to be reset first. These need
401 * to be guaranteed to be the first two instructions.
403 *new_insn++ = BPF_ALU64_REG(BPF_XOR, BPF_REG_A, BPF_REG_A);
404 *new_insn++ = BPF_ALU64_REG(BPF_XOR, BPF_REG_X, BPF_REG_X);
406 /* All programs must keep CTX in callee saved BPF_REG_CTX.
407 * In eBPF case it's done by the compiler, here we need to
408 * do this ourself. Initial CTX is present in BPF_REG_ARG1.
410 *new_insn++ = BPF_MOV64_REG(BPF_REG_CTX, BPF_REG_ARG1);
415 for (i = 0; i < len; fp++, i++) {
416 struct bpf_insn tmp_insns[6] = { };
417 struct bpf_insn *insn = tmp_insns;
420 addrs[i] = new_insn - first_insn;
423 /* All arithmetic insns and skb loads map as-is. */
424 case BPF_ALU | BPF_ADD | BPF_X:
425 case BPF_ALU | BPF_ADD | BPF_K:
426 case BPF_ALU | BPF_SUB | BPF_X:
427 case BPF_ALU | BPF_SUB | BPF_K:
428 case BPF_ALU | BPF_AND | BPF_X:
429 case BPF_ALU | BPF_AND | BPF_K:
430 case BPF_ALU | BPF_OR | BPF_X:
431 case BPF_ALU | BPF_OR | BPF_K:
432 case BPF_ALU | BPF_LSH | BPF_X:
433 case BPF_ALU | BPF_LSH | BPF_K:
434 case BPF_ALU | BPF_RSH | BPF_X:
435 case BPF_ALU | BPF_RSH | BPF_K:
436 case BPF_ALU | BPF_XOR | BPF_X:
437 case BPF_ALU | BPF_XOR | BPF_K:
438 case BPF_ALU | BPF_MUL | BPF_X:
439 case BPF_ALU | BPF_MUL | BPF_K:
440 case BPF_ALU | BPF_DIV | BPF_X:
441 case BPF_ALU | BPF_DIV | BPF_K:
442 case BPF_ALU | BPF_MOD | BPF_X:
443 case BPF_ALU | BPF_MOD | BPF_K:
444 case BPF_ALU | BPF_NEG:
445 case BPF_LD | BPF_ABS | BPF_W:
446 case BPF_LD | BPF_ABS | BPF_H:
447 case BPF_LD | BPF_ABS | BPF_B:
448 case BPF_LD | BPF_IND | BPF_W:
449 case BPF_LD | BPF_IND | BPF_H:
450 case BPF_LD | BPF_IND | BPF_B:
451 /* Check for overloaded BPF extension and
452 * directly convert it if found, otherwise
453 * just move on with mapping.
455 if (BPF_CLASS(fp->code) == BPF_LD &&
456 BPF_MODE(fp->code) == BPF_ABS &&
457 convert_bpf_extensions(fp, &insn))
460 *insn = BPF_RAW_INSN(fp->code, BPF_REG_A, BPF_REG_X, 0, fp->k);
463 /* Jump transformation cannot use BPF block macros
464 * everywhere as offset calculation and target updates
465 * require a bit more work than the rest, i.e. jump
466 * opcodes map as-is, but offsets need adjustment.
469 #define BPF_EMIT_JMP \
471 if (target >= len || target < 0) \
473 insn->off = addrs ? addrs[target] - addrs[i] - 1 : 0; \
474 /* Adjust pc relative offset for 2nd or 3rd insn. */ \
475 insn->off -= insn - tmp_insns; \
478 case BPF_JMP | BPF_JA:
479 target = i + fp->k + 1;
480 insn->code = fp->code;
484 case BPF_JMP | BPF_JEQ | BPF_K:
485 case BPF_JMP | BPF_JEQ | BPF_X:
486 case BPF_JMP | BPF_JSET | BPF_K:
487 case BPF_JMP | BPF_JSET | BPF_X:
488 case BPF_JMP | BPF_JGT | BPF_K:
489 case BPF_JMP | BPF_JGT | BPF_X:
490 case BPF_JMP | BPF_JGE | BPF_K:
491 case BPF_JMP | BPF_JGE | BPF_X:
492 if (BPF_SRC(fp->code) == BPF_K && (int) fp->k < 0) {
493 /* BPF immediates are signed, zero extend
494 * immediate into tmp register and use it
497 *insn++ = BPF_MOV32_IMM(BPF_REG_TMP, fp->k);
499 insn->dst_reg = BPF_REG_A;
500 insn->src_reg = BPF_REG_TMP;
503 insn->dst_reg = BPF_REG_A;
505 bpf_src = BPF_SRC(fp->code);
506 insn->src_reg = bpf_src == BPF_X ? BPF_REG_X : 0;
509 /* Common case where 'jump_false' is next insn. */
511 insn->code = BPF_JMP | BPF_OP(fp->code) | bpf_src;
512 target = i + fp->jt + 1;
517 /* Convert some jumps when 'jump_true' is next insn. */
519 switch (BPF_OP(fp->code)) {
521 insn->code = BPF_JMP | BPF_JNE | bpf_src;
524 insn->code = BPF_JMP | BPF_JLE | bpf_src;
527 insn->code = BPF_JMP | BPF_JLT | bpf_src;
533 target = i + fp->jf + 1;
538 /* Other jumps are mapped into two insns: Jxx and JA. */
539 target = i + fp->jt + 1;
540 insn->code = BPF_JMP | BPF_OP(fp->code) | bpf_src;
544 insn->code = BPF_JMP | BPF_JA;
545 target = i + fp->jf + 1;
549 /* ldxb 4 * ([14] & 0xf) is remaped into 6 insns. */
550 case BPF_LDX | BPF_MSH | BPF_B:
552 *insn++ = BPF_MOV64_REG(BPF_REG_TMP, BPF_REG_A);
553 /* A = BPF_R0 = *(u8 *) (skb->data + K) */
554 *insn++ = BPF_LD_ABS(BPF_B, fp->k);
556 *insn++ = BPF_ALU32_IMM(BPF_AND, BPF_REG_A, 0xf);
558 *insn++ = BPF_ALU32_IMM(BPF_LSH, BPF_REG_A, 2);
560 *insn++ = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A);
562 *insn = BPF_MOV64_REG(BPF_REG_A, BPF_REG_TMP);
565 /* RET_K is remaped into 2 insns. RET_A case doesn't need an
566 * extra mov as BPF_REG_0 is already mapped into BPF_REG_A.
568 case BPF_RET | BPF_A:
569 case BPF_RET | BPF_K:
570 if (BPF_RVAL(fp->code) == BPF_K)
571 *insn++ = BPF_MOV32_RAW(BPF_K, BPF_REG_0,
573 *insn = BPF_EXIT_INSN();
576 /* Store to stack. */
579 stack_off = fp->k * 4 + 4;
580 *insn = BPF_STX_MEM(BPF_W, BPF_REG_FP, BPF_CLASS(fp->code) ==
581 BPF_ST ? BPF_REG_A : BPF_REG_X,
583 /* check_load_and_stores() verifies that classic BPF can
584 * load from stack only after write, so tracking
585 * stack_depth for ST|STX insns is enough
587 if (new_prog && new_prog->aux->stack_depth < stack_off)
588 new_prog->aux->stack_depth = stack_off;
591 /* Load from stack. */
592 case BPF_LD | BPF_MEM:
593 case BPF_LDX | BPF_MEM:
594 stack_off = fp->k * 4 + 4;
595 *insn = BPF_LDX_MEM(BPF_W, BPF_CLASS(fp->code) == BPF_LD ?
596 BPF_REG_A : BPF_REG_X, BPF_REG_FP,
601 case BPF_LD | BPF_IMM:
602 case BPF_LDX | BPF_IMM:
603 *insn = BPF_MOV32_IMM(BPF_CLASS(fp->code) == BPF_LD ?
604 BPF_REG_A : BPF_REG_X, fp->k);
608 case BPF_MISC | BPF_TAX:
609 *insn = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A);
613 case BPF_MISC | BPF_TXA:
614 *insn = BPF_MOV64_REG(BPF_REG_A, BPF_REG_X);
617 /* A = skb->len or X = skb->len */
618 case BPF_LD | BPF_W | BPF_LEN:
619 case BPF_LDX | BPF_W | BPF_LEN:
620 *insn = BPF_LDX_MEM(BPF_W, BPF_CLASS(fp->code) == BPF_LD ?
621 BPF_REG_A : BPF_REG_X, BPF_REG_CTX,
622 offsetof(struct sk_buff, len));
625 /* Access seccomp_data fields. */
626 case BPF_LDX | BPF_ABS | BPF_W:
627 /* A = *(u32 *) (ctx + K) */
628 *insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_CTX, fp->k);
631 /* Unknown instruction. */
638 memcpy(new_insn, tmp_insns,
639 sizeof(*insn) * (insn - tmp_insns));
640 new_insn += insn - tmp_insns;
644 /* Only calculating new length. */
645 *new_len = new_insn - first_insn;
650 if (new_flen != new_insn - first_insn) {
651 new_flen = new_insn - first_insn;
658 BUG_ON(*new_len != new_flen);
667 * As we dont want to clear mem[] array for each packet going through
668 * __bpf_prog_run(), we check that filter loaded by user never try to read
669 * a cell if not previously written, and we check all branches to be sure
670 * a malicious user doesn't try to abuse us.
672 static int check_load_and_stores(const struct sock_filter *filter, int flen)
674 u16 *masks, memvalid = 0; /* One bit per cell, 16 cells */
677 BUILD_BUG_ON(BPF_MEMWORDS > 16);
679 masks = kmalloc_array(flen, sizeof(*masks), GFP_KERNEL);
683 memset(masks, 0xff, flen * sizeof(*masks));
685 for (pc = 0; pc < flen; pc++) {
686 memvalid &= masks[pc];
688 switch (filter[pc].code) {
691 memvalid |= (1 << filter[pc].k);
693 case BPF_LD | BPF_MEM:
694 case BPF_LDX | BPF_MEM:
695 if (!(memvalid & (1 << filter[pc].k))) {
700 case BPF_JMP | BPF_JA:
701 /* A jump must set masks on target */
702 masks[pc + 1 + filter[pc].k] &= memvalid;
705 case BPF_JMP | BPF_JEQ | BPF_K:
706 case BPF_JMP | BPF_JEQ | BPF_X:
707 case BPF_JMP | BPF_JGE | BPF_K:
708 case BPF_JMP | BPF_JGE | BPF_X:
709 case BPF_JMP | BPF_JGT | BPF_K:
710 case BPF_JMP | BPF_JGT | BPF_X:
711 case BPF_JMP | BPF_JSET | BPF_K:
712 case BPF_JMP | BPF_JSET | BPF_X:
713 /* A jump must set masks on targets */
714 masks[pc + 1 + filter[pc].jt] &= memvalid;
715 masks[pc + 1 + filter[pc].jf] &= memvalid;
725 static bool chk_code_allowed(u16 code_to_probe)
727 static const bool codes[] = {
728 /* 32 bit ALU operations */
729 [BPF_ALU | BPF_ADD | BPF_K] = true,
730 [BPF_ALU | BPF_ADD | BPF_X] = true,
731 [BPF_ALU | BPF_SUB | BPF_K] = true,
732 [BPF_ALU | BPF_SUB | BPF_X] = true,
733 [BPF_ALU | BPF_MUL | BPF_K] = true,
734 [BPF_ALU | BPF_MUL | BPF_X] = true,
735 [BPF_ALU | BPF_DIV | BPF_K] = true,
736 [BPF_ALU | BPF_DIV | BPF_X] = true,
737 [BPF_ALU | BPF_MOD | BPF_K] = true,
738 [BPF_ALU | BPF_MOD | BPF_X] = true,
739 [BPF_ALU | BPF_AND | BPF_K] = true,
740 [BPF_ALU | BPF_AND | BPF_X] = true,
741 [BPF_ALU | BPF_OR | BPF_K] = true,
742 [BPF_ALU | BPF_OR | BPF_X] = true,
743 [BPF_ALU | BPF_XOR | BPF_K] = true,
744 [BPF_ALU | BPF_XOR | BPF_X] = true,
745 [BPF_ALU | BPF_LSH | BPF_K] = true,
746 [BPF_ALU | BPF_LSH | BPF_X] = true,
747 [BPF_ALU | BPF_RSH | BPF_K] = true,
748 [BPF_ALU | BPF_RSH | BPF_X] = true,
749 [BPF_ALU | BPF_NEG] = true,
750 /* Load instructions */
751 [BPF_LD | BPF_W | BPF_ABS] = true,
752 [BPF_LD | BPF_H | BPF_ABS] = true,
753 [BPF_LD | BPF_B | BPF_ABS] = true,
754 [BPF_LD | BPF_W | BPF_LEN] = true,
755 [BPF_LD | BPF_W | BPF_IND] = true,
756 [BPF_LD | BPF_H | BPF_IND] = true,
757 [BPF_LD | BPF_B | BPF_IND] = true,
758 [BPF_LD | BPF_IMM] = true,
759 [BPF_LD | BPF_MEM] = true,
760 [BPF_LDX | BPF_W | BPF_LEN] = true,
761 [BPF_LDX | BPF_B | BPF_MSH] = true,
762 [BPF_LDX | BPF_IMM] = true,
763 [BPF_LDX | BPF_MEM] = true,
764 /* Store instructions */
767 /* Misc instructions */
768 [BPF_MISC | BPF_TAX] = true,
769 [BPF_MISC | BPF_TXA] = true,
770 /* Return instructions */
771 [BPF_RET | BPF_K] = true,
772 [BPF_RET | BPF_A] = true,
773 /* Jump instructions */
774 [BPF_JMP | BPF_JA] = true,
775 [BPF_JMP | BPF_JEQ | BPF_K] = true,
776 [BPF_JMP | BPF_JEQ | BPF_X] = true,
777 [BPF_JMP | BPF_JGE | BPF_K] = true,
778 [BPF_JMP | BPF_JGE | BPF_X] = true,
779 [BPF_JMP | BPF_JGT | BPF_K] = true,
780 [BPF_JMP | BPF_JGT | BPF_X] = true,
781 [BPF_JMP | BPF_JSET | BPF_K] = true,
782 [BPF_JMP | BPF_JSET | BPF_X] = true,
785 if (code_to_probe >= ARRAY_SIZE(codes))
788 return codes[code_to_probe];
791 static bool bpf_check_basics_ok(const struct sock_filter *filter,
796 if (flen == 0 || flen > BPF_MAXINSNS)
803 * bpf_check_classic - verify socket filter code
804 * @filter: filter to verify
805 * @flen: length of filter
807 * Check the user's filter code. If we let some ugly
808 * filter code slip through kaboom! The filter must contain
809 * no references or jumps that are out of range, no illegal
810 * instructions, and must end with a RET instruction.
812 * All jumps are forward as they are not signed.
814 * Returns 0 if the rule set is legal or -EINVAL if not.
816 static int bpf_check_classic(const struct sock_filter *filter,
822 /* Check the filter code now */
823 for (pc = 0; pc < flen; pc++) {
824 const struct sock_filter *ftest = &filter[pc];
826 /* May we actually operate on this code? */
827 if (!chk_code_allowed(ftest->code))
830 /* Some instructions need special checks */
831 switch (ftest->code) {
832 case BPF_ALU | BPF_DIV | BPF_K:
833 case BPF_ALU | BPF_MOD | BPF_K:
834 /* Check for division by zero */
838 case BPF_ALU | BPF_LSH | BPF_K:
839 case BPF_ALU | BPF_RSH | BPF_K:
843 case BPF_LD | BPF_MEM:
844 case BPF_LDX | BPF_MEM:
847 /* Check for invalid memory addresses */
848 if (ftest->k >= BPF_MEMWORDS)
851 case BPF_JMP | BPF_JA:
852 /* Note, the large ftest->k might cause loops.
853 * Compare this with conditional jumps below,
854 * where offsets are limited. --ANK (981016)
856 if (ftest->k >= (unsigned int)(flen - pc - 1))
859 case BPF_JMP | BPF_JEQ | BPF_K:
860 case BPF_JMP | BPF_JEQ | BPF_X:
861 case BPF_JMP | BPF_JGE | BPF_K:
862 case BPF_JMP | BPF_JGE | BPF_X:
863 case BPF_JMP | BPF_JGT | BPF_K:
864 case BPF_JMP | BPF_JGT | BPF_X:
865 case BPF_JMP | BPF_JSET | BPF_K:
866 case BPF_JMP | BPF_JSET | BPF_X:
867 /* Both conditionals must be safe */
868 if (pc + ftest->jt + 1 >= flen ||
869 pc + ftest->jf + 1 >= flen)
872 case BPF_LD | BPF_W | BPF_ABS:
873 case BPF_LD | BPF_H | BPF_ABS:
874 case BPF_LD | BPF_B | BPF_ABS:
876 if (bpf_anc_helper(ftest) & BPF_ANC)
878 /* Ancillary operation unknown or unsupported */
879 if (anc_found == false && ftest->k >= SKF_AD_OFF)
884 /* Last instruction must be a RET code */
885 switch (filter[flen - 1].code) {
886 case BPF_RET | BPF_K:
887 case BPF_RET | BPF_A:
888 return check_load_and_stores(filter, flen);
894 static int bpf_prog_store_orig_filter(struct bpf_prog *fp,
895 const struct sock_fprog *fprog)
897 unsigned int fsize = bpf_classic_proglen(fprog);
898 struct sock_fprog_kern *fkprog;
900 fp->orig_prog = kmalloc(sizeof(*fkprog), GFP_KERNEL);
904 fkprog = fp->orig_prog;
905 fkprog->len = fprog->len;
907 fkprog->filter = kmemdup(fp->insns, fsize,
908 GFP_KERNEL | __GFP_NOWARN);
909 if (!fkprog->filter) {
910 kfree(fp->orig_prog);
917 static void bpf_release_orig_filter(struct bpf_prog *fp)
919 struct sock_fprog_kern *fprog = fp->orig_prog;
922 kfree(fprog->filter);
927 static void __bpf_prog_release(struct bpf_prog *prog)
929 if (prog->type == BPF_PROG_TYPE_SOCKET_FILTER) {
932 bpf_release_orig_filter(prog);
937 static void __sk_filter_release(struct sk_filter *fp)
939 __bpf_prog_release(fp->prog);
944 * sk_filter_release_rcu - Release a socket filter by rcu_head
945 * @rcu: rcu_head that contains the sk_filter to free
947 static void sk_filter_release_rcu(struct rcu_head *rcu)
949 struct sk_filter *fp = container_of(rcu, struct sk_filter, rcu);
951 __sk_filter_release(fp);
955 * sk_filter_release - release a socket filter
956 * @fp: filter to remove
958 * Remove a filter from a socket and release its resources.
960 static void sk_filter_release(struct sk_filter *fp)
962 if (refcount_dec_and_test(&fp->refcnt))
963 call_rcu(&fp->rcu, sk_filter_release_rcu);
966 void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp)
968 u32 filter_size = bpf_prog_size(fp->prog->len);
970 atomic_sub(filter_size, &sk->sk_omem_alloc);
971 sk_filter_release(fp);
974 /* try to charge the socket memory if there is space available
975 * return true on success
977 static bool __sk_filter_charge(struct sock *sk, struct sk_filter *fp)
979 u32 filter_size = bpf_prog_size(fp->prog->len);
981 /* same check as in sock_kmalloc() */
982 if (filter_size <= sysctl_optmem_max &&
983 atomic_read(&sk->sk_omem_alloc) + filter_size < sysctl_optmem_max) {
984 atomic_add(filter_size, &sk->sk_omem_alloc);
990 bool sk_filter_charge(struct sock *sk, struct sk_filter *fp)
992 if (!refcount_inc_not_zero(&fp->refcnt))
995 if (!__sk_filter_charge(sk, fp)) {
996 sk_filter_release(fp);
1002 static struct bpf_prog *bpf_migrate_filter(struct bpf_prog *fp)
1004 struct sock_filter *old_prog;
1005 struct bpf_prog *old_fp;
1006 int err, new_len, old_len = fp->len;
1008 /* We are free to overwrite insns et al right here as it
1009 * won't be used at this point in time anymore internally
1010 * after the migration to the internal BPF instruction
1013 BUILD_BUG_ON(sizeof(struct sock_filter) !=
1014 sizeof(struct bpf_insn));
1016 /* Conversion cannot happen on overlapping memory areas,
1017 * so we need to keep the user BPF around until the 2nd
1018 * pass. At this time, the user BPF is stored in fp->insns.
1020 old_prog = kmemdup(fp->insns, old_len * sizeof(struct sock_filter),
1021 GFP_KERNEL | __GFP_NOWARN);
1027 /* 1st pass: calculate the new program length. */
1028 err = bpf_convert_filter(old_prog, old_len, NULL, &new_len);
1032 /* Expand fp for appending the new filter representation. */
1034 fp = bpf_prog_realloc(old_fp, bpf_prog_size(new_len), 0);
1036 /* The old_fp is still around in case we couldn't
1037 * allocate new memory, so uncharge on that one.
1046 /* 2nd pass: remap sock_filter insns into bpf_insn insns. */
1047 err = bpf_convert_filter(old_prog, old_len, fp, &new_len);
1049 /* 2nd bpf_convert_filter() can fail only if it fails
1050 * to allocate memory, remapping must succeed. Note,
1051 * that at this time old_fp has already been released
1056 /* We are guaranteed to never error here with cBPF to eBPF
1057 * transitions, since there's no issue with type compatibility
1058 * checks on program arrays.
1060 fp = bpf_prog_select_runtime(fp, &err);
1068 __bpf_prog_release(fp);
1069 return ERR_PTR(err);
1072 static struct bpf_prog *bpf_prepare_filter(struct bpf_prog *fp,
1073 bpf_aux_classic_check_t trans)
1077 fp->bpf_func = NULL;
1080 err = bpf_check_classic(fp->insns, fp->len);
1082 __bpf_prog_release(fp);
1083 return ERR_PTR(err);
1086 /* There might be additional checks and transformations
1087 * needed on classic filters, f.e. in case of seccomp.
1090 err = trans(fp->insns, fp->len);
1092 __bpf_prog_release(fp);
1093 return ERR_PTR(err);
1097 /* Probe if we can JIT compile the filter and if so, do
1098 * the compilation of the filter.
1100 bpf_jit_compile(fp);
1102 /* JIT compiler couldn't process this filter, so do the
1103 * internal BPF translation for the optimized interpreter.
1106 fp = bpf_migrate_filter(fp);
1112 * bpf_prog_create - create an unattached filter
1113 * @pfp: the unattached filter that is created
1114 * @fprog: the filter program
1116 * Create a filter independent of any socket. We first run some
1117 * sanity checks on it to make sure it does not explode on us later.
1118 * If an error occurs or there is insufficient memory for the filter
1119 * a negative errno code is returned. On success the return is zero.
1121 int bpf_prog_create(struct bpf_prog **pfp, struct sock_fprog_kern *fprog)
1123 unsigned int fsize = bpf_classic_proglen(fprog);
1124 struct bpf_prog *fp;
1126 /* Make sure new filter is there and in the right amounts. */
1127 if (!bpf_check_basics_ok(fprog->filter, fprog->len))
1130 fp = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
1134 memcpy(fp->insns, fprog->filter, fsize);
1136 fp->len = fprog->len;
1137 /* Since unattached filters are not copied back to user
1138 * space through sk_get_filter(), we do not need to hold
1139 * a copy here, and can spare us the work.
1141 fp->orig_prog = NULL;
1143 /* bpf_prepare_filter() already takes care of freeing
1144 * memory in case something goes wrong.
1146 fp = bpf_prepare_filter(fp, NULL);
1153 EXPORT_SYMBOL_GPL(bpf_prog_create);
1156 * bpf_prog_create_from_user - create an unattached filter from user buffer
1157 * @pfp: the unattached filter that is created
1158 * @fprog: the filter program
1159 * @trans: post-classic verifier transformation handler
1160 * @save_orig: save classic BPF program
1162 * This function effectively does the same as bpf_prog_create(), only
1163 * that it builds up its insns buffer from user space provided buffer.
1164 * It also allows for passing a bpf_aux_classic_check_t handler.
1166 int bpf_prog_create_from_user(struct bpf_prog **pfp, struct sock_fprog *fprog,
1167 bpf_aux_classic_check_t trans, bool save_orig)
1169 unsigned int fsize = bpf_classic_proglen(fprog);
1170 struct bpf_prog *fp;
1173 /* Make sure new filter is there and in the right amounts. */
1174 if (!bpf_check_basics_ok(fprog->filter, fprog->len))
1177 fp = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
1181 if (copy_from_user(fp->insns, fprog->filter, fsize)) {
1182 __bpf_prog_free(fp);
1186 fp->len = fprog->len;
1187 fp->orig_prog = NULL;
1190 err = bpf_prog_store_orig_filter(fp, fprog);
1192 __bpf_prog_free(fp);
1197 /* bpf_prepare_filter() already takes care of freeing
1198 * memory in case something goes wrong.
1200 fp = bpf_prepare_filter(fp, trans);
1207 EXPORT_SYMBOL_GPL(bpf_prog_create_from_user);
1209 void bpf_prog_destroy(struct bpf_prog *fp)
1211 __bpf_prog_release(fp);
1213 EXPORT_SYMBOL_GPL(bpf_prog_destroy);
1215 static int __sk_attach_prog(struct bpf_prog *prog, struct sock *sk)
1217 struct sk_filter *fp, *old_fp;
1219 fp = kmalloc(sizeof(*fp), GFP_KERNEL);
1225 if (!__sk_filter_charge(sk, fp)) {
1229 refcount_set(&fp->refcnt, 1);
1231 old_fp = rcu_dereference_protected(sk->sk_filter,
1232 lockdep_sock_is_held(sk));
1233 rcu_assign_pointer(sk->sk_filter, fp);
1236 sk_filter_uncharge(sk, old_fp);
1241 static int __reuseport_attach_prog(struct bpf_prog *prog, struct sock *sk)
1243 struct bpf_prog *old_prog;
1246 if (bpf_prog_size(prog->len) > sysctl_optmem_max)
1249 if (sk_unhashed(sk) && sk->sk_reuseport) {
1250 err = reuseport_alloc(sk);
1253 } else if (!rcu_access_pointer(sk->sk_reuseport_cb)) {
1254 /* The socket wasn't bound with SO_REUSEPORT */
1258 old_prog = reuseport_attach_prog(sk, prog);
1260 bpf_prog_destroy(old_prog);
1266 struct bpf_prog *__get_filter(struct sock_fprog *fprog, struct sock *sk)
1268 unsigned int fsize = bpf_classic_proglen(fprog);
1269 struct bpf_prog *prog;
1272 if (sock_flag(sk, SOCK_FILTER_LOCKED))
1273 return ERR_PTR(-EPERM);
1275 /* Make sure new filter is there and in the right amounts. */
1276 if (!bpf_check_basics_ok(fprog->filter, fprog->len))
1277 return ERR_PTR(-EINVAL);
1279 prog = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
1281 return ERR_PTR(-ENOMEM);
1283 if (copy_from_user(prog->insns, fprog->filter, fsize)) {
1284 __bpf_prog_free(prog);
1285 return ERR_PTR(-EFAULT);
1288 prog->len = fprog->len;
1290 err = bpf_prog_store_orig_filter(prog, fprog);
1292 __bpf_prog_free(prog);
1293 return ERR_PTR(-ENOMEM);
1296 /* bpf_prepare_filter() already takes care of freeing
1297 * memory in case something goes wrong.
1299 return bpf_prepare_filter(prog, NULL);
1303 * sk_attach_filter - attach a socket filter
1304 * @fprog: the filter program
1305 * @sk: the socket to use
1307 * Attach the user's filter code. We first run some sanity checks on
1308 * it to make sure it does not explode on us later. If an error
1309 * occurs or there is insufficient memory for the filter a negative
1310 * errno code is returned. On success the return is zero.
1312 int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk)
1314 struct bpf_prog *prog = __get_filter(fprog, sk);
1318 return PTR_ERR(prog);
1320 err = __sk_attach_prog(prog, sk);
1322 __bpf_prog_release(prog);
1328 EXPORT_SYMBOL_GPL(sk_attach_filter);
1330 int sk_reuseport_attach_filter(struct sock_fprog *fprog, struct sock *sk)
1332 struct bpf_prog *prog = __get_filter(fprog, sk);
1336 return PTR_ERR(prog);
1338 err = __reuseport_attach_prog(prog, sk);
1340 __bpf_prog_release(prog);
1347 static struct bpf_prog *__get_bpf(u32 ufd, struct sock *sk)
1349 if (sock_flag(sk, SOCK_FILTER_LOCKED))
1350 return ERR_PTR(-EPERM);
1352 return bpf_prog_get_type(ufd, BPF_PROG_TYPE_SOCKET_FILTER);
1355 int sk_attach_bpf(u32 ufd, struct sock *sk)
1357 struct bpf_prog *prog = __get_bpf(ufd, sk);
1361 return PTR_ERR(prog);
1363 err = __sk_attach_prog(prog, sk);
1372 int sk_reuseport_attach_bpf(u32 ufd, struct sock *sk)
1374 struct bpf_prog *prog = __get_bpf(ufd, sk);
1378 return PTR_ERR(prog);
1380 err = __reuseport_attach_prog(prog, sk);
1389 struct bpf_scratchpad {
1391 __be32 diff[MAX_BPF_STACK / sizeof(__be32)];
1392 u8 buff[MAX_BPF_STACK];
1396 static DEFINE_PER_CPU(struct bpf_scratchpad, bpf_sp);
1398 static inline int __bpf_try_make_writable(struct sk_buff *skb,
1399 unsigned int write_len)
1401 return skb_ensure_writable(skb, write_len);
1404 static inline int bpf_try_make_writable(struct sk_buff *skb,
1405 unsigned int write_len)
1407 int err = __bpf_try_make_writable(skb, write_len);
1409 bpf_compute_data_end(skb);
1413 static int bpf_try_make_head_writable(struct sk_buff *skb)
1415 return bpf_try_make_writable(skb, skb_headlen(skb));
1418 static inline void bpf_push_mac_rcsum(struct sk_buff *skb)
1420 if (skb_at_tc_ingress(skb))
1421 skb_postpush_rcsum(skb, skb_mac_header(skb), skb->mac_len);
1424 static inline void bpf_pull_mac_rcsum(struct sk_buff *skb)
1426 if (skb_at_tc_ingress(skb))
1427 skb_postpull_rcsum(skb, skb_mac_header(skb), skb->mac_len);
1430 BPF_CALL_5(bpf_skb_store_bytes, struct sk_buff *, skb, u32, offset,
1431 const void *, from, u32, len, u64, flags)
1435 if (unlikely(flags & ~(BPF_F_RECOMPUTE_CSUM | BPF_F_INVALIDATE_HASH)))
1437 if (unlikely(offset > 0xffff))
1439 if (unlikely(bpf_try_make_writable(skb, offset + len)))
1442 ptr = skb->data + offset;
1443 if (flags & BPF_F_RECOMPUTE_CSUM)
1444 __skb_postpull_rcsum(skb, ptr, len, offset);
1446 memcpy(ptr, from, len);
1448 if (flags & BPF_F_RECOMPUTE_CSUM)
1449 __skb_postpush_rcsum(skb, ptr, len, offset);
1450 if (flags & BPF_F_INVALIDATE_HASH)
1451 skb_clear_hash(skb);
1456 static const struct bpf_func_proto bpf_skb_store_bytes_proto = {
1457 .func = bpf_skb_store_bytes,
1459 .ret_type = RET_INTEGER,
1460 .arg1_type = ARG_PTR_TO_CTX,
1461 .arg2_type = ARG_ANYTHING,
1462 .arg3_type = ARG_PTR_TO_MEM,
1463 .arg4_type = ARG_CONST_SIZE,
1464 .arg5_type = ARG_ANYTHING,
1467 BPF_CALL_4(bpf_skb_load_bytes, const struct sk_buff *, skb, u32, offset,
1468 void *, to, u32, len)
1472 if (unlikely(offset > 0xffff))
1475 ptr = skb_header_pointer(skb, offset, len, to);
1479 memcpy(to, ptr, len);
1487 static const struct bpf_func_proto bpf_skb_load_bytes_proto = {
1488 .func = bpf_skb_load_bytes,
1490 .ret_type = RET_INTEGER,
1491 .arg1_type = ARG_PTR_TO_CTX,
1492 .arg2_type = ARG_ANYTHING,
1493 .arg3_type = ARG_PTR_TO_UNINIT_MEM,
1494 .arg4_type = ARG_CONST_SIZE,
1497 BPF_CALL_2(bpf_skb_pull_data, struct sk_buff *, skb, u32, len)
1499 /* Idea is the following: should the needed direct read/write
1500 * test fail during runtime, we can pull in more data and redo
1501 * again, since implicitly, we invalidate previous checks here.
1503 * Or, since we know how much we need to make read/writeable,
1504 * this can be done once at the program beginning for direct
1505 * access case. By this we overcome limitations of only current
1506 * headroom being accessible.
1508 return bpf_try_make_writable(skb, len ? : skb_headlen(skb));
1511 static const struct bpf_func_proto bpf_skb_pull_data_proto = {
1512 .func = bpf_skb_pull_data,
1514 .ret_type = RET_INTEGER,
1515 .arg1_type = ARG_PTR_TO_CTX,
1516 .arg2_type = ARG_ANYTHING,
1519 BPF_CALL_5(bpf_l3_csum_replace, struct sk_buff *, skb, u32, offset,
1520 u64, from, u64, to, u64, flags)
1524 if (unlikely(flags & ~(BPF_F_HDR_FIELD_MASK)))
1526 if (unlikely(offset > 0xffff || offset & 1))
1528 if (unlikely(bpf_try_make_writable(skb, offset + sizeof(*ptr))))
1531 ptr = (__sum16 *)(skb->data + offset);
1532 switch (flags & BPF_F_HDR_FIELD_MASK) {
1534 if (unlikely(from != 0))
1537 csum_replace_by_diff(ptr, to);
1540 csum_replace2(ptr, from, to);
1543 csum_replace4(ptr, from, to);
1552 static const struct bpf_func_proto bpf_l3_csum_replace_proto = {
1553 .func = bpf_l3_csum_replace,
1555 .ret_type = RET_INTEGER,
1556 .arg1_type = ARG_PTR_TO_CTX,
1557 .arg2_type = ARG_ANYTHING,
1558 .arg3_type = ARG_ANYTHING,
1559 .arg4_type = ARG_ANYTHING,
1560 .arg5_type = ARG_ANYTHING,
1563 BPF_CALL_5(bpf_l4_csum_replace, struct sk_buff *, skb, u32, offset,
1564 u64, from, u64, to, u64, flags)
1566 bool is_pseudo = flags & BPF_F_PSEUDO_HDR;
1567 bool is_mmzero = flags & BPF_F_MARK_MANGLED_0;
1568 bool do_mforce = flags & BPF_F_MARK_ENFORCE;
1571 if (unlikely(flags & ~(BPF_F_MARK_MANGLED_0 | BPF_F_MARK_ENFORCE |
1572 BPF_F_PSEUDO_HDR | BPF_F_HDR_FIELD_MASK)))
1574 if (unlikely(offset > 0xffff || offset & 1))
1576 if (unlikely(bpf_try_make_writable(skb, offset + sizeof(*ptr))))
1579 ptr = (__sum16 *)(skb->data + offset);
1580 if (is_mmzero && !do_mforce && !*ptr)
1583 switch (flags & BPF_F_HDR_FIELD_MASK) {
1585 if (unlikely(from != 0))
1588 inet_proto_csum_replace_by_diff(ptr, skb, to, is_pseudo);
1591 inet_proto_csum_replace2(ptr, skb, from, to, is_pseudo);
1594 inet_proto_csum_replace4(ptr, skb, from, to, is_pseudo);
1600 if (is_mmzero && !*ptr)
1601 *ptr = CSUM_MANGLED_0;
1605 static const struct bpf_func_proto bpf_l4_csum_replace_proto = {
1606 .func = bpf_l4_csum_replace,
1608 .ret_type = RET_INTEGER,
1609 .arg1_type = ARG_PTR_TO_CTX,
1610 .arg2_type = ARG_ANYTHING,
1611 .arg3_type = ARG_ANYTHING,
1612 .arg4_type = ARG_ANYTHING,
1613 .arg5_type = ARG_ANYTHING,
1616 BPF_CALL_5(bpf_csum_diff, __be32 *, from, u32, from_size,
1617 __be32 *, to, u32, to_size, __wsum, seed)
1619 struct bpf_scratchpad *sp = this_cpu_ptr(&bpf_sp);
1620 u32 diff_size = from_size + to_size;
1623 /* This is quite flexible, some examples:
1625 * from_size == 0, to_size > 0, seed := csum --> pushing data
1626 * from_size > 0, to_size == 0, seed := csum --> pulling data
1627 * from_size > 0, to_size > 0, seed := 0 --> diffing data
1629 * Even for diffing, from_size and to_size don't need to be equal.
1631 if (unlikely(((from_size | to_size) & (sizeof(__be32) - 1)) ||
1632 diff_size > sizeof(sp->diff)))
1635 for (i = 0; i < from_size / sizeof(__be32); i++, j++)
1636 sp->diff[j] = ~from[i];
1637 for (i = 0; i < to_size / sizeof(__be32); i++, j++)
1638 sp->diff[j] = to[i];
1640 return csum_partial(sp->diff, diff_size, seed);
1643 static const struct bpf_func_proto bpf_csum_diff_proto = {
1644 .func = bpf_csum_diff,
1647 .ret_type = RET_INTEGER,
1648 .arg1_type = ARG_PTR_TO_MEM,
1649 .arg2_type = ARG_CONST_SIZE_OR_ZERO,
1650 .arg3_type = ARG_PTR_TO_MEM,
1651 .arg4_type = ARG_CONST_SIZE_OR_ZERO,
1652 .arg5_type = ARG_ANYTHING,
1655 BPF_CALL_2(bpf_csum_update, struct sk_buff *, skb, __wsum, csum)
1657 /* The interface is to be used in combination with bpf_csum_diff()
1658 * for direct packet writes. csum rotation for alignment as well
1659 * as emulating csum_sub() can be done from the eBPF program.
1661 if (skb->ip_summed == CHECKSUM_COMPLETE)
1662 return (skb->csum = csum_add(skb->csum, csum));
1667 static const struct bpf_func_proto bpf_csum_update_proto = {
1668 .func = bpf_csum_update,
1670 .ret_type = RET_INTEGER,
1671 .arg1_type = ARG_PTR_TO_CTX,
1672 .arg2_type = ARG_ANYTHING,
1675 static inline int __bpf_rx_skb(struct net_device *dev, struct sk_buff *skb)
1677 return dev_forward_skb(dev, skb);
1680 static inline int __bpf_rx_skb_no_mac(struct net_device *dev,
1681 struct sk_buff *skb)
1683 int ret = ____dev_forward_skb(dev, skb);
1687 ret = netif_rx(skb);
1693 static inline int __bpf_tx_skb(struct net_device *dev, struct sk_buff *skb)
1697 if (unlikely(__this_cpu_read(xmit_recursion) > XMIT_RECURSION_LIMIT)) {
1698 net_crit_ratelimited("bpf: recursion limit reached on datapath, buggy bpf program?\n");
1705 __this_cpu_inc(xmit_recursion);
1706 ret = dev_queue_xmit(skb);
1707 __this_cpu_dec(xmit_recursion);
1712 static int __bpf_redirect_no_mac(struct sk_buff *skb, struct net_device *dev,
1715 /* skb->mac_len is not set on normal egress */
1716 unsigned int mlen = skb->network_header - skb->mac_header;
1718 __skb_pull(skb, mlen);
1720 /* At ingress, the mac header has already been pulled once.
1721 * At egress, skb_pospull_rcsum has to be done in case that
1722 * the skb is originated from ingress (i.e. a forwarded skb)
1723 * to ensure that rcsum starts at net header.
1725 if (!skb_at_tc_ingress(skb))
1726 skb_postpull_rcsum(skb, skb_mac_header(skb), mlen);
1727 skb_pop_mac_header(skb);
1728 skb_reset_mac_len(skb);
1729 return flags & BPF_F_INGRESS ?
1730 __bpf_rx_skb_no_mac(dev, skb) : __bpf_tx_skb(dev, skb);
1733 static int __bpf_redirect_common(struct sk_buff *skb, struct net_device *dev,
1736 /* Verify that a link layer header is carried */
1737 if (unlikely(skb->mac_header >= skb->network_header)) {
1742 bpf_push_mac_rcsum(skb);
1743 return flags & BPF_F_INGRESS ?
1744 __bpf_rx_skb(dev, skb) : __bpf_tx_skb(dev, skb);
1747 static int __bpf_redirect(struct sk_buff *skb, struct net_device *dev,
1750 if (dev_is_mac_header_xmit(dev))
1751 return __bpf_redirect_common(skb, dev, flags);
1753 return __bpf_redirect_no_mac(skb, dev, flags);
1756 BPF_CALL_3(bpf_clone_redirect, struct sk_buff *, skb, u32, ifindex, u64, flags)
1758 struct net_device *dev;
1759 struct sk_buff *clone;
1762 if (unlikely(flags & ~(BPF_F_INGRESS)))
1765 dev = dev_get_by_index_rcu(dev_net(skb->dev), ifindex);
1769 clone = skb_clone(skb, GFP_ATOMIC);
1770 if (unlikely(!clone))
1773 /* For direct write, we need to keep the invariant that the skbs
1774 * we're dealing with need to be uncloned. Should uncloning fail
1775 * here, we need to free the just generated clone to unclone once
1778 ret = bpf_try_make_head_writable(skb);
1779 if (unlikely(ret)) {
1784 return __bpf_redirect(clone, dev, flags);
1787 static const struct bpf_func_proto bpf_clone_redirect_proto = {
1788 .func = bpf_clone_redirect,
1790 .ret_type = RET_INTEGER,
1791 .arg1_type = ARG_PTR_TO_CTX,
1792 .arg2_type = ARG_ANYTHING,
1793 .arg3_type = ARG_ANYTHING,
1796 struct redirect_info {
1799 struct bpf_map *map;
1800 struct bpf_map *map_to_flush;
1801 unsigned long map_owner;
1804 static DEFINE_PER_CPU(struct redirect_info, redirect_info);
1806 BPF_CALL_2(bpf_redirect, u32, ifindex, u64, flags)
1808 struct redirect_info *ri = this_cpu_ptr(&redirect_info);
1810 if (unlikely(flags & ~(BPF_F_INGRESS)))
1813 ri->ifindex = ifindex;
1816 return TC_ACT_REDIRECT;
1819 int skb_do_redirect(struct sk_buff *skb)
1821 struct redirect_info *ri = this_cpu_ptr(&redirect_info);
1822 struct net_device *dev;
1824 dev = dev_get_by_index_rcu(dev_net(skb->dev), ri->ifindex);
1826 if (unlikely(!dev)) {
1831 return __bpf_redirect(skb, dev, ri->flags);
1834 static const struct bpf_func_proto bpf_redirect_proto = {
1835 .func = bpf_redirect,
1837 .ret_type = RET_INTEGER,
1838 .arg1_type = ARG_ANYTHING,
1839 .arg2_type = ARG_ANYTHING,
1842 BPF_CALL_4(bpf_sk_redirect_map, struct sk_buff *, skb,
1843 struct bpf_map *, map, u32, key, u64, flags)
1845 struct tcp_skb_cb *tcb = TCP_SKB_CB(skb);
1847 /* If user passes invalid input drop the packet. */
1848 if (unlikely(flags))
1852 tcb->bpf.flags = flags;
1858 struct sock *do_sk_redirect_map(struct sk_buff *skb)
1860 struct tcp_skb_cb *tcb = TCP_SKB_CB(skb);
1861 struct sock *sk = NULL;
1864 sk = __sock_map_lookup_elem(tcb->bpf.map, tcb->bpf.key);
1867 tcb->bpf.map = NULL;
1873 static const struct bpf_func_proto bpf_sk_redirect_map_proto = {
1874 .func = bpf_sk_redirect_map,
1876 .ret_type = RET_INTEGER,
1877 .arg1_type = ARG_PTR_TO_CTX,
1878 .arg2_type = ARG_CONST_MAP_PTR,
1879 .arg3_type = ARG_ANYTHING,
1880 .arg4_type = ARG_ANYTHING,
1883 BPF_CALL_1(bpf_get_cgroup_classid, const struct sk_buff *, skb)
1885 return task_get_classid(skb);
1888 static const struct bpf_func_proto bpf_get_cgroup_classid_proto = {
1889 .func = bpf_get_cgroup_classid,
1891 .ret_type = RET_INTEGER,
1892 .arg1_type = ARG_PTR_TO_CTX,
1895 BPF_CALL_1(bpf_get_route_realm, const struct sk_buff *, skb)
1897 return dst_tclassid(skb);
1900 static const struct bpf_func_proto bpf_get_route_realm_proto = {
1901 .func = bpf_get_route_realm,
1903 .ret_type = RET_INTEGER,
1904 .arg1_type = ARG_PTR_TO_CTX,
1907 BPF_CALL_1(bpf_get_hash_recalc, struct sk_buff *, skb)
1909 /* If skb_clear_hash() was called due to mangling, we can
1910 * trigger SW recalculation here. Later access to hash
1911 * can then use the inline skb->hash via context directly
1912 * instead of calling this helper again.
1914 return skb_get_hash(skb);
1917 static const struct bpf_func_proto bpf_get_hash_recalc_proto = {
1918 .func = bpf_get_hash_recalc,
1920 .ret_type = RET_INTEGER,
1921 .arg1_type = ARG_PTR_TO_CTX,
1924 BPF_CALL_1(bpf_set_hash_invalid, struct sk_buff *, skb)
1926 /* After all direct packet write, this can be used once for
1927 * triggering a lazy recalc on next skb_get_hash() invocation.
1929 skb_clear_hash(skb);
1933 static const struct bpf_func_proto bpf_set_hash_invalid_proto = {
1934 .func = bpf_set_hash_invalid,
1936 .ret_type = RET_INTEGER,
1937 .arg1_type = ARG_PTR_TO_CTX,
1940 BPF_CALL_2(bpf_set_hash, struct sk_buff *, skb, u32, hash)
1942 /* Set user specified hash as L4(+), so that it gets returned
1943 * on skb_get_hash() call unless BPF prog later on triggers a
1946 __skb_set_sw_hash(skb, hash, true);
1950 static const struct bpf_func_proto bpf_set_hash_proto = {
1951 .func = bpf_set_hash,
1953 .ret_type = RET_INTEGER,
1954 .arg1_type = ARG_PTR_TO_CTX,
1955 .arg2_type = ARG_ANYTHING,
1958 BPF_CALL_3(bpf_skb_vlan_push, struct sk_buff *, skb, __be16, vlan_proto,
1963 if (unlikely(vlan_proto != htons(ETH_P_8021Q) &&
1964 vlan_proto != htons(ETH_P_8021AD)))
1965 vlan_proto = htons(ETH_P_8021Q);
1967 bpf_push_mac_rcsum(skb);
1968 ret = skb_vlan_push(skb, vlan_proto, vlan_tci);
1969 bpf_pull_mac_rcsum(skb);
1971 bpf_compute_data_end(skb);
1975 const struct bpf_func_proto bpf_skb_vlan_push_proto = {
1976 .func = bpf_skb_vlan_push,
1978 .ret_type = RET_INTEGER,
1979 .arg1_type = ARG_PTR_TO_CTX,
1980 .arg2_type = ARG_ANYTHING,
1981 .arg3_type = ARG_ANYTHING,
1983 EXPORT_SYMBOL_GPL(bpf_skb_vlan_push_proto);
1985 BPF_CALL_1(bpf_skb_vlan_pop, struct sk_buff *, skb)
1989 bpf_push_mac_rcsum(skb);
1990 ret = skb_vlan_pop(skb);
1991 bpf_pull_mac_rcsum(skb);
1993 bpf_compute_data_end(skb);
1997 const struct bpf_func_proto bpf_skb_vlan_pop_proto = {
1998 .func = bpf_skb_vlan_pop,
2000 .ret_type = RET_INTEGER,
2001 .arg1_type = ARG_PTR_TO_CTX,
2003 EXPORT_SYMBOL_GPL(bpf_skb_vlan_pop_proto);
2005 static int bpf_skb_generic_push(struct sk_buff *skb, u32 off, u32 len)
2007 /* Caller already did skb_cow() with len as headroom,
2008 * so no need to do it here.
2011 memmove(skb->data, skb->data + len, off);
2012 memset(skb->data + off, 0, len);
2014 /* No skb_postpush_rcsum(skb, skb->data + off, len)
2015 * needed here as it does not change the skb->csum
2016 * result for checksum complete when summing over
2022 static int bpf_skb_generic_pop(struct sk_buff *skb, u32 off, u32 len)
2024 /* skb_ensure_writable() is not needed here, as we're
2025 * already working on an uncloned skb.
2027 if (unlikely(!pskb_may_pull(skb, off + len)))
2030 skb_postpull_rcsum(skb, skb->data + off, len);
2031 memmove(skb->data + len, skb->data, off);
2032 __skb_pull(skb, len);
2037 static int bpf_skb_net_hdr_push(struct sk_buff *skb, u32 off, u32 len)
2039 bool trans_same = skb->transport_header == skb->network_header;
2042 /* There's no need for __skb_push()/__skb_pull() pair to
2043 * get to the start of the mac header as we're guaranteed
2044 * to always start from here under eBPF.
2046 ret = bpf_skb_generic_push(skb, off, len);
2048 skb->mac_header -= len;
2049 skb->network_header -= len;
2051 skb->transport_header = skb->network_header;
2057 static int bpf_skb_net_hdr_pop(struct sk_buff *skb, u32 off, u32 len)
2059 bool trans_same = skb->transport_header == skb->network_header;
2062 /* Same here, __skb_push()/__skb_pull() pair not needed. */
2063 ret = bpf_skb_generic_pop(skb, off, len);
2065 skb->mac_header += len;
2066 skb->network_header += len;
2068 skb->transport_header = skb->network_header;
2074 static int bpf_skb_proto_4_to_6(struct sk_buff *skb)
2076 const u32 len_diff = sizeof(struct ipv6hdr) - sizeof(struct iphdr);
2077 u32 off = skb_mac_header_len(skb);
2080 ret = skb_cow(skb, len_diff);
2081 if (unlikely(ret < 0))
2084 ret = bpf_skb_net_hdr_push(skb, off, len_diff);
2085 if (unlikely(ret < 0))
2088 if (skb_is_gso(skb)) {
2089 /* SKB_GSO_TCPV4 needs to be changed into
2092 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4) {
2093 skb_shinfo(skb)->gso_type &= ~SKB_GSO_TCPV4;
2094 skb_shinfo(skb)->gso_type |= SKB_GSO_TCPV6;
2097 /* Due to IPv6 header, MSS needs to be downgraded. */
2098 skb_shinfo(skb)->gso_size -= len_diff;
2099 /* Header must be checked, and gso_segs recomputed. */
2100 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
2101 skb_shinfo(skb)->gso_segs = 0;
2104 skb->protocol = htons(ETH_P_IPV6);
2105 skb_clear_hash(skb);
2110 static int bpf_skb_proto_6_to_4(struct sk_buff *skb)
2112 const u32 len_diff = sizeof(struct ipv6hdr) - sizeof(struct iphdr);
2113 u32 off = skb_mac_header_len(skb);
2116 ret = skb_unclone(skb, GFP_ATOMIC);
2117 if (unlikely(ret < 0))
2120 ret = bpf_skb_net_hdr_pop(skb, off, len_diff);
2121 if (unlikely(ret < 0))
2124 if (skb_is_gso(skb)) {
2125 /* SKB_GSO_TCPV6 needs to be changed into
2128 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6) {
2129 skb_shinfo(skb)->gso_type &= ~SKB_GSO_TCPV6;
2130 skb_shinfo(skb)->gso_type |= SKB_GSO_TCPV4;
2133 /* Due to IPv4 header, MSS can be upgraded. */
2134 skb_shinfo(skb)->gso_size += len_diff;
2135 /* Header must be checked, and gso_segs recomputed. */
2136 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
2137 skb_shinfo(skb)->gso_segs = 0;
2140 skb->protocol = htons(ETH_P_IP);
2141 skb_clear_hash(skb);
2146 static int bpf_skb_proto_xlat(struct sk_buff *skb, __be16 to_proto)
2148 __be16 from_proto = skb->protocol;
2150 if (from_proto == htons(ETH_P_IP) &&
2151 to_proto == htons(ETH_P_IPV6))
2152 return bpf_skb_proto_4_to_6(skb);
2154 if (from_proto == htons(ETH_P_IPV6) &&
2155 to_proto == htons(ETH_P_IP))
2156 return bpf_skb_proto_6_to_4(skb);
2161 BPF_CALL_3(bpf_skb_change_proto, struct sk_buff *, skb, __be16, proto,
2166 if (unlikely(flags))
2169 /* General idea is that this helper does the basic groundwork
2170 * needed for changing the protocol, and eBPF program fills the
2171 * rest through bpf_skb_store_bytes(), bpf_lX_csum_replace()
2172 * and other helpers, rather than passing a raw buffer here.
2174 * The rationale is to keep this minimal and without a need to
2175 * deal with raw packet data. F.e. even if we would pass buffers
2176 * here, the program still needs to call the bpf_lX_csum_replace()
2177 * helpers anyway. Plus, this way we keep also separation of
2178 * concerns, since f.e. bpf_skb_store_bytes() should only take
2181 * Currently, additional options and extension header space are
2182 * not supported, but flags register is reserved so we can adapt
2183 * that. For offloads, we mark packet as dodgy, so that headers
2184 * need to be verified first.
2186 ret = bpf_skb_proto_xlat(skb, proto);
2187 bpf_compute_data_end(skb);
2191 static const struct bpf_func_proto bpf_skb_change_proto_proto = {
2192 .func = bpf_skb_change_proto,
2194 .ret_type = RET_INTEGER,
2195 .arg1_type = ARG_PTR_TO_CTX,
2196 .arg2_type = ARG_ANYTHING,
2197 .arg3_type = ARG_ANYTHING,
2200 BPF_CALL_2(bpf_skb_change_type, struct sk_buff *, skb, u32, pkt_type)
2202 /* We only allow a restricted subset to be changed for now. */
2203 if (unlikely(!skb_pkt_type_ok(skb->pkt_type) ||
2204 !skb_pkt_type_ok(pkt_type)))
2207 skb->pkt_type = pkt_type;
2211 static const struct bpf_func_proto bpf_skb_change_type_proto = {
2212 .func = bpf_skb_change_type,
2214 .ret_type = RET_INTEGER,
2215 .arg1_type = ARG_PTR_TO_CTX,
2216 .arg2_type = ARG_ANYTHING,
2219 static u32 bpf_skb_net_base_len(const struct sk_buff *skb)
2221 switch (skb->protocol) {
2222 case htons(ETH_P_IP):
2223 return sizeof(struct iphdr);
2224 case htons(ETH_P_IPV6):
2225 return sizeof(struct ipv6hdr);
2231 static int bpf_skb_net_grow(struct sk_buff *skb, u32 len_diff)
2233 u32 off = skb_mac_header_len(skb) + bpf_skb_net_base_len(skb);
2236 ret = skb_cow(skb, len_diff);
2237 if (unlikely(ret < 0))
2240 ret = bpf_skb_net_hdr_push(skb, off, len_diff);
2241 if (unlikely(ret < 0))
2244 if (skb_is_gso(skb)) {
2245 /* Due to header grow, MSS needs to be downgraded. */
2246 skb_shinfo(skb)->gso_size -= len_diff;
2247 /* Header must be checked, and gso_segs recomputed. */
2248 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
2249 skb_shinfo(skb)->gso_segs = 0;
2255 static int bpf_skb_net_shrink(struct sk_buff *skb, u32 len_diff)
2257 u32 off = skb_mac_header_len(skb) + bpf_skb_net_base_len(skb);
2260 ret = skb_unclone(skb, GFP_ATOMIC);
2261 if (unlikely(ret < 0))
2264 ret = bpf_skb_net_hdr_pop(skb, off, len_diff);
2265 if (unlikely(ret < 0))
2268 if (skb_is_gso(skb)) {
2269 /* Due to header shrink, MSS can be upgraded. */
2270 skb_shinfo(skb)->gso_size += len_diff;
2271 /* Header must be checked, and gso_segs recomputed. */
2272 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
2273 skb_shinfo(skb)->gso_segs = 0;
2279 static u32 __bpf_skb_max_len(const struct sk_buff *skb)
2281 return skb->dev->mtu + skb->dev->hard_header_len;
2284 static int bpf_skb_adjust_net(struct sk_buff *skb, s32 len_diff)
2286 bool trans_same = skb->transport_header == skb->network_header;
2287 u32 len_cur, len_diff_abs = abs(len_diff);
2288 u32 len_min = bpf_skb_net_base_len(skb);
2289 u32 len_max = __bpf_skb_max_len(skb);
2290 __be16 proto = skb->protocol;
2291 bool shrink = len_diff < 0;
2294 if (unlikely(len_diff_abs > 0xfffU))
2296 if (unlikely(proto != htons(ETH_P_IP) &&
2297 proto != htons(ETH_P_IPV6)))
2300 len_cur = skb->len - skb_network_offset(skb);
2301 if (skb_transport_header_was_set(skb) && !trans_same)
2302 len_cur = skb_network_header_len(skb);
2303 if ((shrink && (len_diff_abs >= len_cur ||
2304 len_cur - len_diff_abs < len_min)) ||
2305 (!shrink && (skb->len + len_diff_abs > len_max &&
2309 ret = shrink ? bpf_skb_net_shrink(skb, len_diff_abs) :
2310 bpf_skb_net_grow(skb, len_diff_abs);
2312 bpf_compute_data_end(skb);
2316 BPF_CALL_4(bpf_skb_adjust_room, struct sk_buff *, skb, s32, len_diff,
2317 u32, mode, u64, flags)
2319 if (unlikely(flags))
2321 if (likely(mode == BPF_ADJ_ROOM_NET))
2322 return bpf_skb_adjust_net(skb, len_diff);
2327 static const struct bpf_func_proto bpf_skb_adjust_room_proto = {
2328 .func = bpf_skb_adjust_room,
2330 .ret_type = RET_INTEGER,
2331 .arg1_type = ARG_PTR_TO_CTX,
2332 .arg2_type = ARG_ANYTHING,
2333 .arg3_type = ARG_ANYTHING,
2334 .arg4_type = ARG_ANYTHING,
2337 static u32 __bpf_skb_min_len(const struct sk_buff *skb)
2339 u32 min_len = skb_network_offset(skb);
2341 if (skb_transport_header_was_set(skb))
2342 min_len = skb_transport_offset(skb);
2343 if (skb->ip_summed == CHECKSUM_PARTIAL)
2344 min_len = skb_checksum_start_offset(skb) +
2345 skb->csum_offset + sizeof(__sum16);
2349 static int bpf_skb_grow_rcsum(struct sk_buff *skb, unsigned int new_len)
2351 unsigned int old_len = skb->len;
2354 ret = __skb_grow_rcsum(skb, new_len);
2356 memset(skb->data + old_len, 0, new_len - old_len);
2360 static int bpf_skb_trim_rcsum(struct sk_buff *skb, unsigned int new_len)
2362 return __skb_trim_rcsum(skb, new_len);
2365 BPF_CALL_3(bpf_skb_change_tail, struct sk_buff *, skb, u32, new_len,
2368 u32 max_len = __bpf_skb_max_len(skb);
2369 u32 min_len = __bpf_skb_min_len(skb);
2372 if (unlikely(flags || new_len > max_len || new_len < min_len))
2374 if (skb->encapsulation)
2377 /* The basic idea of this helper is that it's performing the
2378 * needed work to either grow or trim an skb, and eBPF program
2379 * rewrites the rest via helpers like bpf_skb_store_bytes(),
2380 * bpf_lX_csum_replace() and others rather than passing a raw
2381 * buffer here. This one is a slow path helper and intended
2382 * for replies with control messages.
2384 * Like in bpf_skb_change_proto(), we want to keep this rather
2385 * minimal and without protocol specifics so that we are able
2386 * to separate concerns as in bpf_skb_store_bytes() should only
2387 * be the one responsible for writing buffers.
2389 * It's really expected to be a slow path operation here for
2390 * control message replies, so we're implicitly linearizing,
2391 * uncloning and drop offloads from the skb by this.
2393 ret = __bpf_try_make_writable(skb, skb->len);
2395 if (new_len > skb->len)
2396 ret = bpf_skb_grow_rcsum(skb, new_len);
2397 else if (new_len < skb->len)
2398 ret = bpf_skb_trim_rcsum(skb, new_len);
2399 if (!ret && skb_is_gso(skb))
2403 bpf_compute_data_end(skb);
2407 static const struct bpf_func_proto bpf_skb_change_tail_proto = {
2408 .func = bpf_skb_change_tail,
2410 .ret_type = RET_INTEGER,
2411 .arg1_type = ARG_PTR_TO_CTX,
2412 .arg2_type = ARG_ANYTHING,
2413 .arg3_type = ARG_ANYTHING,
2416 BPF_CALL_3(bpf_skb_change_head, struct sk_buff *, skb, u32, head_room,
2419 u32 max_len = __bpf_skb_max_len(skb);
2420 u32 new_len = skb->len + head_room;
2423 if (unlikely(flags || (!skb_is_gso(skb) && new_len > max_len) ||
2424 new_len < skb->len))
2427 ret = skb_cow(skb, head_room);
2429 /* Idea for this helper is that we currently only
2430 * allow to expand on mac header. This means that
2431 * skb->protocol network header, etc, stay as is.
2432 * Compared to bpf_skb_change_tail(), we're more
2433 * flexible due to not needing to linearize or
2434 * reset GSO. Intention for this helper is to be
2435 * used by an L3 skb that needs to push mac header
2436 * for redirection into L2 device.
2438 __skb_push(skb, head_room);
2439 memset(skb->data, 0, head_room);
2440 skb_reset_mac_header(skb);
2443 bpf_compute_data_end(skb);
2447 static const struct bpf_func_proto bpf_skb_change_head_proto = {
2448 .func = bpf_skb_change_head,
2450 .ret_type = RET_INTEGER,
2451 .arg1_type = ARG_PTR_TO_CTX,
2452 .arg2_type = ARG_ANYTHING,
2453 .arg3_type = ARG_ANYTHING,
2456 BPF_CALL_2(bpf_xdp_adjust_head, struct xdp_buff *, xdp, int, offset)
2458 void *data = xdp->data + offset;
2460 if (unlikely(data < xdp->data_hard_start ||
2461 data > xdp->data_end - ETH_HLEN))
2469 static const struct bpf_func_proto bpf_xdp_adjust_head_proto = {
2470 .func = bpf_xdp_adjust_head,
2472 .ret_type = RET_INTEGER,
2473 .arg1_type = ARG_PTR_TO_CTX,
2474 .arg2_type = ARG_ANYTHING,
2477 static int __bpf_tx_xdp(struct net_device *dev,
2478 struct bpf_map *map,
2479 struct xdp_buff *xdp,
2484 if (!dev->netdev_ops->ndo_xdp_xmit) {
2488 err = dev->netdev_ops->ndo_xdp_xmit(dev, xdp);
2492 __dev_map_insert_ctx(map, index);
2494 dev->netdev_ops->ndo_xdp_flush(dev);
2498 void xdp_do_flush_map(void)
2500 struct redirect_info *ri = this_cpu_ptr(&redirect_info);
2501 struct bpf_map *map = ri->map_to_flush;
2503 ri->map_to_flush = NULL;
2505 __dev_map_flush(map);
2507 EXPORT_SYMBOL_GPL(xdp_do_flush_map);
2509 static inline bool xdp_map_invalid(const struct bpf_prog *xdp_prog,
2512 return (unsigned long)xdp_prog->aux != aux;
2515 static int xdp_do_redirect_map(struct net_device *dev, struct xdp_buff *xdp,
2516 struct bpf_prog *xdp_prog)
2518 struct redirect_info *ri = this_cpu_ptr(&redirect_info);
2519 unsigned long map_owner = ri->map_owner;
2520 struct bpf_map *map = ri->map;
2521 struct net_device *fwd = NULL;
2522 u32 index = ri->ifindex;
2529 if (unlikely(xdp_map_invalid(xdp_prog, map_owner))) {
2535 fwd = __dev_map_lookup_elem(map, index);
2540 if (ri->map_to_flush && ri->map_to_flush != map)
2543 err = __bpf_tx_xdp(fwd, map, xdp, index);
2547 ri->map_to_flush = map;
2548 _trace_xdp_redirect_map(dev, xdp_prog, fwd, map, index);
2551 _trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map, index, err);
2555 int xdp_do_redirect(struct net_device *dev, struct xdp_buff *xdp,
2556 struct bpf_prog *xdp_prog)
2558 struct redirect_info *ri = this_cpu_ptr(&redirect_info);
2559 struct net_device *fwd;
2560 u32 index = ri->ifindex;
2564 return xdp_do_redirect_map(dev, xdp, xdp_prog);
2566 fwd = dev_get_by_index_rcu(dev_net(dev), index);
2568 if (unlikely(!fwd)) {
2573 err = __bpf_tx_xdp(fwd, NULL, xdp, 0);
2577 _trace_xdp_redirect(dev, xdp_prog, index);
2580 _trace_xdp_redirect_err(dev, xdp_prog, index, err);
2583 EXPORT_SYMBOL_GPL(xdp_do_redirect);
2585 int xdp_do_generic_redirect(struct net_device *dev, struct sk_buff *skb,
2586 struct bpf_prog *xdp_prog)
2588 struct redirect_info *ri = this_cpu_ptr(&redirect_info);
2589 unsigned long map_owner = ri->map_owner;
2590 struct bpf_map *map = ri->map;
2591 struct net_device *fwd = NULL;
2592 u32 index = ri->ifindex;
2601 if (unlikely(xdp_map_invalid(xdp_prog, map_owner))) {
2606 fwd = __dev_map_lookup_elem(map, index);
2608 fwd = dev_get_by_index_rcu(dev_net(dev), index);
2610 if (unlikely(!fwd)) {
2615 if (unlikely(!(fwd->flags & IFF_UP))) {
2620 len = fwd->mtu + fwd->hard_header_len + VLAN_HLEN;
2621 if (skb->len > len) {
2627 map ? _trace_xdp_redirect_map(dev, xdp_prog, fwd, map, index)
2628 : _trace_xdp_redirect(dev, xdp_prog, index);
2631 map ? _trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map, index, err)
2632 : _trace_xdp_redirect_err(dev, xdp_prog, index, err);
2635 EXPORT_SYMBOL_GPL(xdp_do_generic_redirect);
2637 BPF_CALL_2(bpf_xdp_redirect, u32, ifindex, u64, flags)
2639 struct redirect_info *ri = this_cpu_ptr(&redirect_info);
2641 if (unlikely(flags))
2644 ri->ifindex = ifindex;
2649 return XDP_REDIRECT;
2652 static const struct bpf_func_proto bpf_xdp_redirect_proto = {
2653 .func = bpf_xdp_redirect,
2655 .ret_type = RET_INTEGER,
2656 .arg1_type = ARG_ANYTHING,
2657 .arg2_type = ARG_ANYTHING,
2660 BPF_CALL_4(bpf_xdp_redirect_map, struct bpf_map *, map, u32, ifindex, u64, flags,
2661 unsigned long, map_owner)
2663 struct redirect_info *ri = this_cpu_ptr(&redirect_info);
2665 if (unlikely(flags))
2668 ri->ifindex = ifindex;
2671 ri->map_owner = map_owner;
2673 return XDP_REDIRECT;
2676 /* Note, arg4 is hidden from users and populated by the verifier
2677 * with the right pointer.
2679 static const struct bpf_func_proto bpf_xdp_redirect_map_proto = {
2680 .func = bpf_xdp_redirect_map,
2682 .ret_type = RET_INTEGER,
2683 .arg1_type = ARG_CONST_MAP_PTR,
2684 .arg2_type = ARG_ANYTHING,
2685 .arg3_type = ARG_ANYTHING,
2688 bool bpf_helper_changes_pkt_data(void *func)
2690 if (func == bpf_skb_vlan_push ||
2691 func == bpf_skb_vlan_pop ||
2692 func == bpf_skb_store_bytes ||
2693 func == bpf_skb_change_proto ||
2694 func == bpf_skb_change_head ||
2695 func == bpf_skb_change_tail ||
2696 func == bpf_skb_adjust_room ||
2697 func == bpf_skb_pull_data ||
2698 func == bpf_clone_redirect ||
2699 func == bpf_l3_csum_replace ||
2700 func == bpf_l4_csum_replace ||
2701 func == bpf_xdp_adjust_head)
2707 static unsigned long bpf_skb_copy(void *dst_buff, const void *skb,
2708 unsigned long off, unsigned long len)
2710 void *ptr = skb_header_pointer(skb, off, len, dst_buff);
2714 if (ptr != dst_buff)
2715 memcpy(dst_buff, ptr, len);
2720 BPF_CALL_5(bpf_skb_event_output, struct sk_buff *, skb, struct bpf_map *, map,
2721 u64, flags, void *, meta, u64, meta_size)
2723 u64 skb_size = (flags & BPF_F_CTXLEN_MASK) >> 32;
2725 if (unlikely(flags & ~(BPF_F_CTXLEN_MASK | BPF_F_INDEX_MASK)))
2727 if (unlikely(skb_size > skb->len))
2730 return bpf_event_output(map, flags, meta, meta_size, skb, skb_size,
2734 static const struct bpf_func_proto bpf_skb_event_output_proto = {
2735 .func = bpf_skb_event_output,
2737 .ret_type = RET_INTEGER,
2738 .arg1_type = ARG_PTR_TO_CTX,
2739 .arg2_type = ARG_CONST_MAP_PTR,
2740 .arg3_type = ARG_ANYTHING,
2741 .arg4_type = ARG_PTR_TO_MEM,
2742 .arg5_type = ARG_CONST_SIZE,
2745 static unsigned short bpf_tunnel_key_af(u64 flags)
2747 return flags & BPF_F_TUNINFO_IPV6 ? AF_INET6 : AF_INET;
2750 BPF_CALL_4(bpf_skb_get_tunnel_key, struct sk_buff *, skb, struct bpf_tunnel_key *, to,
2751 u32, size, u64, flags)
2753 const struct ip_tunnel_info *info = skb_tunnel_info(skb);
2754 u8 compat[sizeof(struct bpf_tunnel_key)];
2758 if (unlikely(!info || (flags & ~(BPF_F_TUNINFO_IPV6)))) {
2762 if (ip_tunnel_info_af(info) != bpf_tunnel_key_af(flags)) {
2766 if (unlikely(size != sizeof(struct bpf_tunnel_key))) {
2769 case offsetof(struct bpf_tunnel_key, tunnel_label):
2770 case offsetof(struct bpf_tunnel_key, tunnel_ext):
2772 case offsetof(struct bpf_tunnel_key, remote_ipv6[1]):
2773 /* Fixup deprecated structure layouts here, so we have
2774 * a common path later on.
2776 if (ip_tunnel_info_af(info) != AF_INET)
2779 to = (struct bpf_tunnel_key *)compat;
2786 to->tunnel_id = be64_to_cpu(info->key.tun_id);
2787 to->tunnel_tos = info->key.tos;
2788 to->tunnel_ttl = info->key.ttl;
2790 if (flags & BPF_F_TUNINFO_IPV6) {
2791 memcpy(to->remote_ipv6, &info->key.u.ipv6.src,
2792 sizeof(to->remote_ipv6));
2793 to->tunnel_label = be32_to_cpu(info->key.label);
2795 to->remote_ipv4 = be32_to_cpu(info->key.u.ipv4.src);
2798 if (unlikely(size != sizeof(struct bpf_tunnel_key)))
2799 memcpy(to_orig, to, size);
2803 memset(to_orig, 0, size);
2807 static const struct bpf_func_proto bpf_skb_get_tunnel_key_proto = {
2808 .func = bpf_skb_get_tunnel_key,
2810 .ret_type = RET_INTEGER,
2811 .arg1_type = ARG_PTR_TO_CTX,
2812 .arg2_type = ARG_PTR_TO_UNINIT_MEM,
2813 .arg3_type = ARG_CONST_SIZE,
2814 .arg4_type = ARG_ANYTHING,
2817 BPF_CALL_3(bpf_skb_get_tunnel_opt, struct sk_buff *, skb, u8 *, to, u32, size)
2819 const struct ip_tunnel_info *info = skb_tunnel_info(skb);
2822 if (unlikely(!info ||
2823 !(info->key.tun_flags & TUNNEL_OPTIONS_PRESENT))) {
2827 if (unlikely(size < info->options_len)) {
2832 ip_tunnel_info_opts_get(to, info);
2833 if (size > info->options_len)
2834 memset(to + info->options_len, 0, size - info->options_len);
2836 return info->options_len;
2838 memset(to, 0, size);
2842 static const struct bpf_func_proto bpf_skb_get_tunnel_opt_proto = {
2843 .func = bpf_skb_get_tunnel_opt,
2845 .ret_type = RET_INTEGER,
2846 .arg1_type = ARG_PTR_TO_CTX,
2847 .arg2_type = ARG_PTR_TO_UNINIT_MEM,
2848 .arg3_type = ARG_CONST_SIZE,
2851 static struct metadata_dst __percpu *md_dst;
2853 BPF_CALL_4(bpf_skb_set_tunnel_key, struct sk_buff *, skb,
2854 const struct bpf_tunnel_key *, from, u32, size, u64, flags)
2856 struct metadata_dst *md = this_cpu_ptr(md_dst);
2857 u8 compat[sizeof(struct bpf_tunnel_key)];
2858 struct ip_tunnel_info *info;
2860 if (unlikely(flags & ~(BPF_F_TUNINFO_IPV6 | BPF_F_ZERO_CSUM_TX |
2861 BPF_F_DONT_FRAGMENT)))
2863 if (unlikely(size != sizeof(struct bpf_tunnel_key))) {
2865 case offsetof(struct bpf_tunnel_key, tunnel_label):
2866 case offsetof(struct bpf_tunnel_key, tunnel_ext):
2867 case offsetof(struct bpf_tunnel_key, remote_ipv6[1]):
2868 /* Fixup deprecated structure layouts here, so we have
2869 * a common path later on.
2871 memcpy(compat, from, size);
2872 memset(compat + size, 0, sizeof(compat) - size);
2873 from = (const struct bpf_tunnel_key *) compat;
2879 if (unlikely((!(flags & BPF_F_TUNINFO_IPV6) && from->tunnel_label) ||
2884 dst_hold((struct dst_entry *) md);
2885 skb_dst_set(skb, (struct dst_entry *) md);
2887 info = &md->u.tun_info;
2888 info->mode = IP_TUNNEL_INFO_TX;
2890 info->key.tun_flags = TUNNEL_KEY | TUNNEL_CSUM | TUNNEL_NOCACHE;
2891 if (flags & BPF_F_DONT_FRAGMENT)
2892 info->key.tun_flags |= TUNNEL_DONT_FRAGMENT;
2894 info->key.tun_id = cpu_to_be64(from->tunnel_id);
2895 info->key.tos = from->tunnel_tos;
2896 info->key.ttl = from->tunnel_ttl;
2898 if (flags & BPF_F_TUNINFO_IPV6) {
2899 info->mode |= IP_TUNNEL_INFO_IPV6;
2900 memcpy(&info->key.u.ipv6.dst, from->remote_ipv6,
2901 sizeof(from->remote_ipv6));
2902 info->key.label = cpu_to_be32(from->tunnel_label) &
2903 IPV6_FLOWLABEL_MASK;
2905 info->key.u.ipv4.dst = cpu_to_be32(from->remote_ipv4);
2906 if (flags & BPF_F_ZERO_CSUM_TX)
2907 info->key.tun_flags &= ~TUNNEL_CSUM;
2913 static const struct bpf_func_proto bpf_skb_set_tunnel_key_proto = {
2914 .func = bpf_skb_set_tunnel_key,
2916 .ret_type = RET_INTEGER,
2917 .arg1_type = ARG_PTR_TO_CTX,
2918 .arg2_type = ARG_PTR_TO_MEM,
2919 .arg3_type = ARG_CONST_SIZE,
2920 .arg4_type = ARG_ANYTHING,
2923 BPF_CALL_3(bpf_skb_set_tunnel_opt, struct sk_buff *, skb,
2924 const u8 *, from, u32, size)
2926 struct ip_tunnel_info *info = skb_tunnel_info(skb);
2927 const struct metadata_dst *md = this_cpu_ptr(md_dst);
2929 if (unlikely(info != &md->u.tun_info || (size & (sizeof(u32) - 1))))
2931 if (unlikely(size > IP_TUNNEL_OPTS_MAX))
2934 ip_tunnel_info_opts_set(info, from, size);
2939 static const struct bpf_func_proto bpf_skb_set_tunnel_opt_proto = {
2940 .func = bpf_skb_set_tunnel_opt,
2942 .ret_type = RET_INTEGER,
2943 .arg1_type = ARG_PTR_TO_CTX,
2944 .arg2_type = ARG_PTR_TO_MEM,
2945 .arg3_type = ARG_CONST_SIZE,
2948 static const struct bpf_func_proto *
2949 bpf_get_skb_set_tunnel_proto(enum bpf_func_id which)
2952 /* Race is not possible, since it's called from verifier
2953 * that is holding verifier mutex.
2955 md_dst = metadata_dst_alloc_percpu(IP_TUNNEL_OPTS_MAX,
2963 case BPF_FUNC_skb_set_tunnel_key:
2964 return &bpf_skb_set_tunnel_key_proto;
2965 case BPF_FUNC_skb_set_tunnel_opt:
2966 return &bpf_skb_set_tunnel_opt_proto;
2972 BPF_CALL_3(bpf_skb_under_cgroup, struct sk_buff *, skb, struct bpf_map *, map,
2975 struct bpf_array *array = container_of(map, struct bpf_array, map);
2976 struct cgroup *cgrp;
2979 sk = skb_to_full_sk(skb);
2980 if (!sk || !sk_fullsock(sk))
2982 if (unlikely(idx >= array->map.max_entries))
2985 cgrp = READ_ONCE(array->ptrs[idx]);
2986 if (unlikely(!cgrp))
2989 return sk_under_cgroup_hierarchy(sk, cgrp);
2992 static const struct bpf_func_proto bpf_skb_under_cgroup_proto = {
2993 .func = bpf_skb_under_cgroup,
2995 .ret_type = RET_INTEGER,
2996 .arg1_type = ARG_PTR_TO_CTX,
2997 .arg2_type = ARG_CONST_MAP_PTR,
2998 .arg3_type = ARG_ANYTHING,
3001 static unsigned long bpf_xdp_copy(void *dst_buff, const void *src_buff,
3002 unsigned long off, unsigned long len)
3004 memcpy(dst_buff, src_buff + off, len);
3008 BPF_CALL_5(bpf_xdp_event_output, struct xdp_buff *, xdp, struct bpf_map *, map,
3009 u64, flags, void *, meta, u64, meta_size)
3011 u64 xdp_size = (flags & BPF_F_CTXLEN_MASK) >> 32;
3013 if (unlikely(flags & ~(BPF_F_CTXLEN_MASK | BPF_F_INDEX_MASK)))
3015 if (unlikely(xdp_size > (unsigned long)(xdp->data_end - xdp->data)))
3018 return bpf_event_output(map, flags, meta, meta_size, xdp->data,
3019 xdp_size, bpf_xdp_copy);
3022 static const struct bpf_func_proto bpf_xdp_event_output_proto = {
3023 .func = bpf_xdp_event_output,
3025 .ret_type = RET_INTEGER,
3026 .arg1_type = ARG_PTR_TO_CTX,
3027 .arg2_type = ARG_CONST_MAP_PTR,
3028 .arg3_type = ARG_ANYTHING,
3029 .arg4_type = ARG_PTR_TO_MEM,
3030 .arg5_type = ARG_CONST_SIZE,
3033 BPF_CALL_1(bpf_get_socket_cookie, struct sk_buff *, skb)
3035 return skb->sk ? sock_gen_cookie(skb->sk) : 0;
3038 static const struct bpf_func_proto bpf_get_socket_cookie_proto = {
3039 .func = bpf_get_socket_cookie,
3041 .ret_type = RET_INTEGER,
3042 .arg1_type = ARG_PTR_TO_CTX,
3045 BPF_CALL_1(bpf_get_socket_uid, struct sk_buff *, skb)
3047 struct sock *sk = sk_to_full_sk(skb->sk);
3050 if (!sk || !sk_fullsock(sk))
3052 kuid = sock_net_uid(sock_net(sk), sk);
3053 return from_kuid_munged(sock_net(sk)->user_ns, kuid);
3056 static const struct bpf_func_proto bpf_get_socket_uid_proto = {
3057 .func = bpf_get_socket_uid,
3059 .ret_type = RET_INTEGER,
3060 .arg1_type = ARG_PTR_TO_CTX,
3063 BPF_CALL_5(bpf_setsockopt, struct bpf_sock_ops_kern *, bpf_sock,
3064 int, level, int, optname, char *, optval, int, optlen)
3066 struct sock *sk = bpf_sock->sk;
3070 if (!sk_fullsock(sk))
3073 if (level == SOL_SOCKET) {
3074 if (optlen != sizeof(int))
3076 val = *((int *)optval);
3078 /* Only some socketops are supported */
3081 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
3082 sk->sk_rcvbuf = max_t(int, val * 2, SOCK_MIN_RCVBUF);
3085 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
3086 sk->sk_sndbuf = max_t(int, val * 2, SOCK_MIN_SNDBUF);
3088 case SO_MAX_PACING_RATE:
3089 sk->sk_max_pacing_rate = val;
3090 sk->sk_pacing_rate = min(sk->sk_pacing_rate,
3091 sk->sk_max_pacing_rate);
3094 sk->sk_priority = val;
3099 sk->sk_rcvlowat = val ? : 1;
3108 } else if (level == SOL_TCP &&
3109 sk->sk_prot->setsockopt == tcp_setsockopt) {
3110 if (optname == TCP_CONGESTION) {
3111 char name[TCP_CA_NAME_MAX];
3112 bool reinit = bpf_sock->op > BPF_SOCK_OPS_NEEDS_ECN;
3114 strncpy(name, optval, min_t(long, optlen,
3115 TCP_CA_NAME_MAX-1));
3116 name[TCP_CA_NAME_MAX-1] = 0;
3117 ret = tcp_set_congestion_control(sk, name, false, reinit);
3119 struct tcp_sock *tp = tcp_sk(sk);
3121 if (optlen != sizeof(int))
3124 val = *((int *)optval);
3125 /* Only some options are supported */
3128 if (val <= 0 || tp->data_segs_out > 0)
3133 case TCP_BPF_SNDCWND_CLAMP:
3137 tp->snd_cwnd_clamp = val;
3138 tp->snd_ssthresh = val;
3152 static const struct bpf_func_proto bpf_setsockopt_proto = {
3153 .func = bpf_setsockopt,
3155 .ret_type = RET_INTEGER,
3156 .arg1_type = ARG_PTR_TO_CTX,
3157 .arg2_type = ARG_ANYTHING,
3158 .arg3_type = ARG_ANYTHING,
3159 .arg4_type = ARG_PTR_TO_MEM,
3160 .arg5_type = ARG_CONST_SIZE,
3163 static const struct bpf_func_proto *
3164 bpf_base_func_proto(enum bpf_func_id func_id)
3167 case BPF_FUNC_map_lookup_elem:
3168 return &bpf_map_lookup_elem_proto;
3169 case BPF_FUNC_map_update_elem:
3170 return &bpf_map_update_elem_proto;
3171 case BPF_FUNC_map_delete_elem:
3172 return &bpf_map_delete_elem_proto;
3173 case BPF_FUNC_get_prandom_u32:
3174 return &bpf_get_prandom_u32_proto;
3175 case BPF_FUNC_get_smp_processor_id:
3176 return &bpf_get_raw_smp_processor_id_proto;
3177 case BPF_FUNC_get_numa_node_id:
3178 return &bpf_get_numa_node_id_proto;
3179 case BPF_FUNC_tail_call:
3180 return &bpf_tail_call_proto;
3181 case BPF_FUNC_ktime_get_ns:
3182 return &bpf_ktime_get_ns_proto;
3183 case BPF_FUNC_trace_printk:
3184 if (capable(CAP_SYS_ADMIN))
3185 return bpf_get_trace_printk_proto();
3191 static const struct bpf_func_proto *
3192 sock_filter_func_proto(enum bpf_func_id func_id)
3195 /* inet and inet6 sockets are created in a process
3196 * context so there is always a valid uid/gid
3198 case BPF_FUNC_get_current_uid_gid:
3199 return &bpf_get_current_uid_gid_proto;
3201 return bpf_base_func_proto(func_id);
3205 static const struct bpf_func_proto *
3206 sk_filter_func_proto(enum bpf_func_id func_id)
3209 case BPF_FUNC_skb_load_bytes:
3210 return &bpf_skb_load_bytes_proto;
3211 case BPF_FUNC_get_socket_cookie:
3212 return &bpf_get_socket_cookie_proto;
3213 case BPF_FUNC_get_socket_uid:
3214 return &bpf_get_socket_uid_proto;
3216 return bpf_base_func_proto(func_id);
3220 static const struct bpf_func_proto *
3221 tc_cls_act_func_proto(enum bpf_func_id func_id)
3224 case BPF_FUNC_skb_store_bytes:
3225 return &bpf_skb_store_bytes_proto;
3226 case BPF_FUNC_skb_load_bytes:
3227 return &bpf_skb_load_bytes_proto;
3228 case BPF_FUNC_skb_pull_data:
3229 return &bpf_skb_pull_data_proto;
3230 case BPF_FUNC_csum_diff:
3231 return &bpf_csum_diff_proto;
3232 case BPF_FUNC_csum_update:
3233 return &bpf_csum_update_proto;
3234 case BPF_FUNC_l3_csum_replace:
3235 return &bpf_l3_csum_replace_proto;
3236 case BPF_FUNC_l4_csum_replace:
3237 return &bpf_l4_csum_replace_proto;
3238 case BPF_FUNC_clone_redirect:
3239 return &bpf_clone_redirect_proto;
3240 case BPF_FUNC_get_cgroup_classid:
3241 return &bpf_get_cgroup_classid_proto;
3242 case BPF_FUNC_skb_vlan_push:
3243 return &bpf_skb_vlan_push_proto;
3244 case BPF_FUNC_skb_vlan_pop:
3245 return &bpf_skb_vlan_pop_proto;
3246 case BPF_FUNC_skb_change_proto:
3247 return &bpf_skb_change_proto_proto;
3248 case BPF_FUNC_skb_change_type:
3249 return &bpf_skb_change_type_proto;
3250 case BPF_FUNC_skb_adjust_room:
3251 return &bpf_skb_adjust_room_proto;
3252 case BPF_FUNC_skb_change_tail:
3253 return &bpf_skb_change_tail_proto;
3254 case BPF_FUNC_skb_get_tunnel_key:
3255 return &bpf_skb_get_tunnel_key_proto;
3256 case BPF_FUNC_skb_set_tunnel_key:
3257 return bpf_get_skb_set_tunnel_proto(func_id);
3258 case BPF_FUNC_skb_get_tunnel_opt:
3259 return &bpf_skb_get_tunnel_opt_proto;
3260 case BPF_FUNC_skb_set_tunnel_opt:
3261 return bpf_get_skb_set_tunnel_proto(func_id);
3262 case BPF_FUNC_redirect:
3263 return &bpf_redirect_proto;
3264 case BPF_FUNC_get_route_realm:
3265 return &bpf_get_route_realm_proto;
3266 case BPF_FUNC_get_hash_recalc:
3267 return &bpf_get_hash_recalc_proto;
3268 case BPF_FUNC_set_hash_invalid:
3269 return &bpf_set_hash_invalid_proto;
3270 case BPF_FUNC_set_hash:
3271 return &bpf_set_hash_proto;
3272 case BPF_FUNC_perf_event_output:
3273 return &bpf_skb_event_output_proto;
3274 case BPF_FUNC_get_smp_processor_id:
3275 return &bpf_get_smp_processor_id_proto;
3276 case BPF_FUNC_skb_under_cgroup:
3277 return &bpf_skb_under_cgroup_proto;
3278 case BPF_FUNC_get_socket_cookie:
3279 return &bpf_get_socket_cookie_proto;
3280 case BPF_FUNC_get_socket_uid:
3281 return &bpf_get_socket_uid_proto;
3283 return bpf_base_func_proto(func_id);
3287 static const struct bpf_func_proto *
3288 xdp_func_proto(enum bpf_func_id func_id)
3291 case BPF_FUNC_perf_event_output:
3292 return &bpf_xdp_event_output_proto;
3293 case BPF_FUNC_get_smp_processor_id:
3294 return &bpf_get_smp_processor_id_proto;
3295 case BPF_FUNC_xdp_adjust_head:
3296 return &bpf_xdp_adjust_head_proto;
3297 case BPF_FUNC_redirect:
3298 return &bpf_xdp_redirect_proto;
3299 case BPF_FUNC_redirect_map:
3300 return &bpf_xdp_redirect_map_proto;
3302 return bpf_base_func_proto(func_id);
3306 static const struct bpf_func_proto *
3307 lwt_inout_func_proto(enum bpf_func_id func_id)
3310 case BPF_FUNC_skb_load_bytes:
3311 return &bpf_skb_load_bytes_proto;
3312 case BPF_FUNC_skb_pull_data:
3313 return &bpf_skb_pull_data_proto;
3314 case BPF_FUNC_csum_diff:
3315 return &bpf_csum_diff_proto;
3316 case BPF_FUNC_get_cgroup_classid:
3317 return &bpf_get_cgroup_classid_proto;
3318 case BPF_FUNC_get_route_realm:
3319 return &bpf_get_route_realm_proto;
3320 case BPF_FUNC_get_hash_recalc:
3321 return &bpf_get_hash_recalc_proto;
3322 case BPF_FUNC_perf_event_output:
3323 return &bpf_skb_event_output_proto;
3324 case BPF_FUNC_get_smp_processor_id:
3325 return &bpf_get_smp_processor_id_proto;
3326 case BPF_FUNC_skb_under_cgroup:
3327 return &bpf_skb_under_cgroup_proto;
3329 return bpf_base_func_proto(func_id);
3333 static const struct bpf_func_proto *
3334 sock_ops_func_proto(enum bpf_func_id func_id)
3337 case BPF_FUNC_setsockopt:
3338 return &bpf_setsockopt_proto;
3339 case BPF_FUNC_sock_map_update:
3340 return &bpf_sock_map_update_proto;
3342 return bpf_base_func_proto(func_id);
3346 static const struct bpf_func_proto *sk_skb_func_proto(enum bpf_func_id func_id)
3349 case BPF_FUNC_skb_store_bytes:
3350 return &bpf_skb_store_bytes_proto;
3351 case BPF_FUNC_skb_load_bytes:
3352 return &bpf_skb_load_bytes_proto;
3353 case BPF_FUNC_skb_pull_data:
3354 return &bpf_skb_pull_data_proto;
3355 case BPF_FUNC_skb_change_tail:
3356 return &bpf_skb_change_tail_proto;
3357 case BPF_FUNC_skb_change_head:
3358 return &bpf_skb_change_head_proto;
3359 case BPF_FUNC_get_socket_cookie:
3360 return &bpf_get_socket_cookie_proto;
3361 case BPF_FUNC_get_socket_uid:
3362 return &bpf_get_socket_uid_proto;
3363 case BPF_FUNC_sk_redirect_map:
3364 return &bpf_sk_redirect_map_proto;
3366 return bpf_base_func_proto(func_id);
3370 static const struct bpf_func_proto *
3371 lwt_xmit_func_proto(enum bpf_func_id func_id)
3374 case BPF_FUNC_skb_get_tunnel_key:
3375 return &bpf_skb_get_tunnel_key_proto;
3376 case BPF_FUNC_skb_set_tunnel_key:
3377 return bpf_get_skb_set_tunnel_proto(func_id);
3378 case BPF_FUNC_skb_get_tunnel_opt:
3379 return &bpf_skb_get_tunnel_opt_proto;
3380 case BPF_FUNC_skb_set_tunnel_opt:
3381 return bpf_get_skb_set_tunnel_proto(func_id);
3382 case BPF_FUNC_redirect:
3383 return &bpf_redirect_proto;
3384 case BPF_FUNC_clone_redirect:
3385 return &bpf_clone_redirect_proto;
3386 case BPF_FUNC_skb_change_tail:
3387 return &bpf_skb_change_tail_proto;
3388 case BPF_FUNC_skb_change_head:
3389 return &bpf_skb_change_head_proto;
3390 case BPF_FUNC_skb_store_bytes:
3391 return &bpf_skb_store_bytes_proto;
3392 case BPF_FUNC_csum_update:
3393 return &bpf_csum_update_proto;
3394 case BPF_FUNC_l3_csum_replace:
3395 return &bpf_l3_csum_replace_proto;
3396 case BPF_FUNC_l4_csum_replace:
3397 return &bpf_l4_csum_replace_proto;
3398 case BPF_FUNC_set_hash_invalid:
3399 return &bpf_set_hash_invalid_proto;
3401 return lwt_inout_func_proto(func_id);
3405 static bool bpf_skb_is_valid_access(int off, int size, enum bpf_access_type type,
3406 struct bpf_insn_access_aux *info)
3408 const int size_default = sizeof(__u32);
3410 if (off < 0 || off >= sizeof(struct __sk_buff))
3413 /* The verifier guarantees that size > 0. */
3414 if (off % size != 0)
3418 case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
3419 if (off + size > offsetofend(struct __sk_buff, cb[4]))
3422 case bpf_ctx_range_till(struct __sk_buff, remote_ip6[0], remote_ip6[3]):
3423 case bpf_ctx_range_till(struct __sk_buff, local_ip6[0], local_ip6[3]):
3424 case bpf_ctx_range_till(struct __sk_buff, remote_ip4, remote_ip4):
3425 case bpf_ctx_range_till(struct __sk_buff, local_ip4, local_ip4):
3426 case bpf_ctx_range(struct __sk_buff, data):
3427 case bpf_ctx_range(struct __sk_buff, data_end):
3428 if (size != size_default)
3432 /* Only narrow read access allowed for now. */
3433 if (type == BPF_WRITE) {
3434 if (size != size_default)
3437 bpf_ctx_record_field_size(info, size_default);
3438 if (!bpf_ctx_narrow_access_ok(off, size, size_default))
3446 static bool sk_filter_is_valid_access(int off, int size,
3447 enum bpf_access_type type,
3448 struct bpf_insn_access_aux *info)
3451 case bpf_ctx_range(struct __sk_buff, tc_classid):
3452 case bpf_ctx_range(struct __sk_buff, data):
3453 case bpf_ctx_range(struct __sk_buff, data_end):
3454 case bpf_ctx_range_till(struct __sk_buff, family, local_port):
3458 if (type == BPF_WRITE) {
3460 case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
3467 return bpf_skb_is_valid_access(off, size, type, info);
3470 static bool lwt_is_valid_access(int off, int size,
3471 enum bpf_access_type type,
3472 struct bpf_insn_access_aux *info)
3475 case bpf_ctx_range(struct __sk_buff, tc_classid):
3476 case bpf_ctx_range_till(struct __sk_buff, family, local_port):
3480 if (type == BPF_WRITE) {
3482 case bpf_ctx_range(struct __sk_buff, mark):
3483 case bpf_ctx_range(struct __sk_buff, priority):
3484 case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
3492 case bpf_ctx_range(struct __sk_buff, data):
3493 info->reg_type = PTR_TO_PACKET;
3495 case bpf_ctx_range(struct __sk_buff, data_end):
3496 info->reg_type = PTR_TO_PACKET_END;
3500 return bpf_skb_is_valid_access(off, size, type, info);
3503 static bool sock_filter_is_valid_access(int off, int size,
3504 enum bpf_access_type type,
3505 struct bpf_insn_access_aux *info)
3507 if (type == BPF_WRITE) {
3509 case offsetof(struct bpf_sock, bound_dev_if):
3510 case offsetof(struct bpf_sock, mark):
3511 case offsetof(struct bpf_sock, priority):
3518 if (off < 0 || off + size > sizeof(struct bpf_sock))
3520 /* The verifier guarantees that size > 0. */
3521 if (off % size != 0)
3523 if (size != sizeof(__u32))
3529 static int bpf_unclone_prologue(struct bpf_insn *insn_buf, bool direct_write,
3530 const struct bpf_prog *prog, int drop_verdict)
3532 struct bpf_insn *insn = insn_buf;
3537 /* if (!skb->cloned)
3540 * (Fast-path, otherwise approximation that we might be
3541 * a clone, do the rest in helper.)
3543 *insn++ = BPF_LDX_MEM(BPF_B, BPF_REG_6, BPF_REG_1, CLONED_OFFSET());
3544 *insn++ = BPF_ALU32_IMM(BPF_AND, BPF_REG_6, CLONED_MASK);
3545 *insn++ = BPF_JMP_IMM(BPF_JEQ, BPF_REG_6, 0, 7);
3547 /* ret = bpf_skb_pull_data(skb, 0); */
3548 *insn++ = BPF_MOV64_REG(BPF_REG_6, BPF_REG_1);
3549 *insn++ = BPF_ALU64_REG(BPF_XOR, BPF_REG_2, BPF_REG_2);
3550 *insn++ = BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
3551 BPF_FUNC_skb_pull_data);
3554 * return TC_ACT_SHOT;
3556 *insn++ = BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2);
3557 *insn++ = BPF_ALU32_IMM(BPF_MOV, BPF_REG_0, drop_verdict);
3558 *insn++ = BPF_EXIT_INSN();
3561 *insn++ = BPF_MOV64_REG(BPF_REG_1, BPF_REG_6);
3563 *insn++ = prog->insnsi[0];
3565 return insn - insn_buf;
3568 static int tc_cls_act_prologue(struct bpf_insn *insn_buf, bool direct_write,
3569 const struct bpf_prog *prog)
3571 return bpf_unclone_prologue(insn_buf, direct_write, prog, TC_ACT_SHOT);
3574 static bool tc_cls_act_is_valid_access(int off, int size,
3575 enum bpf_access_type type,
3576 struct bpf_insn_access_aux *info)
3578 if (type == BPF_WRITE) {
3580 case bpf_ctx_range(struct __sk_buff, mark):
3581 case bpf_ctx_range(struct __sk_buff, tc_index):
3582 case bpf_ctx_range(struct __sk_buff, priority):
3583 case bpf_ctx_range(struct __sk_buff, tc_classid):
3584 case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
3592 case bpf_ctx_range(struct __sk_buff, data):
3593 info->reg_type = PTR_TO_PACKET;
3595 case bpf_ctx_range(struct __sk_buff, data_end):
3596 info->reg_type = PTR_TO_PACKET_END;
3598 case bpf_ctx_range_till(struct __sk_buff, family, local_port):
3602 return bpf_skb_is_valid_access(off, size, type, info);
3605 static bool __is_valid_xdp_access(int off, int size)
3607 if (off < 0 || off >= sizeof(struct xdp_md))
3609 if (off % size != 0)
3611 if (size != sizeof(__u32))
3617 static bool xdp_is_valid_access(int off, int size,
3618 enum bpf_access_type type,
3619 struct bpf_insn_access_aux *info)
3621 if (type == BPF_WRITE)
3625 case offsetof(struct xdp_md, data):
3626 info->reg_type = PTR_TO_PACKET;
3628 case offsetof(struct xdp_md, data_end):
3629 info->reg_type = PTR_TO_PACKET_END;
3633 return __is_valid_xdp_access(off, size);
3636 void bpf_warn_invalid_xdp_action(u32 act)
3638 const u32 act_max = XDP_REDIRECT;
3640 WARN_ONCE(1, "%s XDP return value %u, expect packet loss!\n",
3641 act > act_max ? "Illegal" : "Driver unsupported",
3644 EXPORT_SYMBOL_GPL(bpf_warn_invalid_xdp_action);
3646 static bool __is_valid_sock_ops_access(int off, int size)
3648 if (off < 0 || off >= sizeof(struct bpf_sock_ops))
3650 /* The verifier guarantees that size > 0. */
3651 if (off % size != 0)
3653 if (size != sizeof(__u32))
3659 static bool sock_ops_is_valid_access(int off, int size,
3660 enum bpf_access_type type,
3661 struct bpf_insn_access_aux *info)
3663 if (type == BPF_WRITE) {
3665 case offsetof(struct bpf_sock_ops, op) ...
3666 offsetof(struct bpf_sock_ops, replylong[3]):
3673 return __is_valid_sock_ops_access(off, size);
3676 static int sk_skb_prologue(struct bpf_insn *insn_buf, bool direct_write,
3677 const struct bpf_prog *prog)
3679 return bpf_unclone_prologue(insn_buf, direct_write, prog, SK_DROP);
3682 static bool sk_skb_is_valid_access(int off, int size,
3683 enum bpf_access_type type,
3684 struct bpf_insn_access_aux *info)
3686 if (type == BPF_WRITE) {
3688 case bpf_ctx_range(struct __sk_buff, tc_index):
3689 case bpf_ctx_range(struct __sk_buff, priority):
3697 case bpf_ctx_range(struct __sk_buff, mark):
3698 case bpf_ctx_range(struct __sk_buff, tc_classid):
3700 case bpf_ctx_range(struct __sk_buff, data):
3701 info->reg_type = PTR_TO_PACKET;
3703 case bpf_ctx_range(struct __sk_buff, data_end):
3704 info->reg_type = PTR_TO_PACKET_END;
3708 return bpf_skb_is_valid_access(off, size, type, info);
3711 static u32 bpf_convert_ctx_access(enum bpf_access_type type,
3712 const struct bpf_insn *si,
3713 struct bpf_insn *insn_buf,
3714 struct bpf_prog *prog, u32 *target_size)
3716 struct bpf_insn *insn = insn_buf;
3720 case offsetof(struct __sk_buff, len):
3721 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
3722 bpf_target_off(struct sk_buff, len, 4,
3726 case offsetof(struct __sk_buff, protocol):
3727 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
3728 bpf_target_off(struct sk_buff, protocol, 2,
3732 case offsetof(struct __sk_buff, vlan_proto):
3733 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
3734 bpf_target_off(struct sk_buff, vlan_proto, 2,
3738 case offsetof(struct __sk_buff, priority):
3739 if (type == BPF_WRITE)
3740 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
3741 bpf_target_off(struct sk_buff, priority, 4,
3744 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
3745 bpf_target_off(struct sk_buff, priority, 4,
3749 case offsetof(struct __sk_buff, ingress_ifindex):
3750 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
3751 bpf_target_off(struct sk_buff, skb_iif, 4,
3755 case offsetof(struct __sk_buff, ifindex):
3756 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev),
3757 si->dst_reg, si->src_reg,
3758 offsetof(struct sk_buff, dev));
3759 *insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
3760 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
3761 bpf_target_off(struct net_device, ifindex, 4,
3765 case offsetof(struct __sk_buff, hash):
3766 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
3767 bpf_target_off(struct sk_buff, hash, 4,
3771 case offsetof(struct __sk_buff, mark):
3772 if (type == BPF_WRITE)
3773 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
3774 bpf_target_off(struct sk_buff, mark, 4,
3777 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
3778 bpf_target_off(struct sk_buff, mark, 4,
3782 case offsetof(struct __sk_buff, pkt_type):
3784 *insn++ = BPF_LDX_MEM(BPF_B, si->dst_reg, si->src_reg,
3786 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, PKT_TYPE_MAX);
3787 #ifdef __BIG_ENDIAN_BITFIELD
3788 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, 5);
3792 case offsetof(struct __sk_buff, queue_mapping):
3793 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
3794 bpf_target_off(struct sk_buff, queue_mapping, 2,
3798 case offsetof(struct __sk_buff, vlan_present):
3799 case offsetof(struct __sk_buff, vlan_tci):
3800 BUILD_BUG_ON(VLAN_TAG_PRESENT != 0x1000);
3802 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
3803 bpf_target_off(struct sk_buff, vlan_tci, 2,
3805 if (si->off == offsetof(struct __sk_buff, vlan_tci)) {
3806 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg,
3809 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, 12);
3810 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, 1);
3814 case offsetof(struct __sk_buff, cb[0]) ...
3815 offsetofend(struct __sk_buff, cb[4]) - 1:
3816 BUILD_BUG_ON(FIELD_SIZEOF(struct qdisc_skb_cb, data) < 20);
3817 BUILD_BUG_ON((offsetof(struct sk_buff, cb) +
3818 offsetof(struct qdisc_skb_cb, data)) %
3821 prog->cb_access = 1;
3823 off -= offsetof(struct __sk_buff, cb[0]);
3824 off += offsetof(struct sk_buff, cb);
3825 off += offsetof(struct qdisc_skb_cb, data);
3826 if (type == BPF_WRITE)
3827 *insn++ = BPF_STX_MEM(BPF_SIZE(si->code), si->dst_reg,
3830 *insn++ = BPF_LDX_MEM(BPF_SIZE(si->code), si->dst_reg,
3834 case offsetof(struct __sk_buff, tc_classid):
3835 BUILD_BUG_ON(FIELD_SIZEOF(struct qdisc_skb_cb, tc_classid) != 2);
3838 off -= offsetof(struct __sk_buff, tc_classid);
3839 off += offsetof(struct sk_buff, cb);
3840 off += offsetof(struct qdisc_skb_cb, tc_classid);
3842 if (type == BPF_WRITE)
3843 *insn++ = BPF_STX_MEM(BPF_H, si->dst_reg,
3846 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg,
3850 case offsetof(struct __sk_buff, data):
3851 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data),
3852 si->dst_reg, si->src_reg,
3853 offsetof(struct sk_buff, data));
3856 case offsetof(struct __sk_buff, data_end):
3858 off -= offsetof(struct __sk_buff, data_end);
3859 off += offsetof(struct sk_buff, cb);
3860 off += offsetof(struct bpf_skb_data_end, data_end);
3861 *insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg,
3865 case offsetof(struct __sk_buff, tc_index):
3866 #ifdef CONFIG_NET_SCHED
3867 if (type == BPF_WRITE)
3868 *insn++ = BPF_STX_MEM(BPF_H, si->dst_reg, si->src_reg,
3869 bpf_target_off(struct sk_buff, tc_index, 2,
3872 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
3873 bpf_target_off(struct sk_buff, tc_index, 2,
3877 if (type == BPF_WRITE)
3878 *insn++ = BPF_MOV64_REG(si->dst_reg, si->dst_reg);
3880 *insn++ = BPF_MOV64_IMM(si->dst_reg, 0);
3884 case offsetof(struct __sk_buff, napi_id):
3885 #if defined(CONFIG_NET_RX_BUSY_POLL)
3886 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
3887 bpf_target_off(struct sk_buff, napi_id, 4,
3889 *insn++ = BPF_JMP_IMM(BPF_JGE, si->dst_reg, MIN_NAPI_ID, 1);
3890 *insn++ = BPF_MOV64_IMM(si->dst_reg, 0);
3893 *insn++ = BPF_MOV64_IMM(si->dst_reg, 0);
3896 case offsetof(struct __sk_buff, family):
3897 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_family) != 2);
3899 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
3900 si->dst_reg, si->src_reg,
3901 offsetof(struct sk_buff, sk));
3902 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
3903 bpf_target_off(struct sock_common,
3907 case offsetof(struct __sk_buff, remote_ip4):
3908 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_daddr) != 4);
3910 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
3911 si->dst_reg, si->src_reg,
3912 offsetof(struct sk_buff, sk));
3913 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
3914 bpf_target_off(struct sock_common,
3918 case offsetof(struct __sk_buff, local_ip4):
3919 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common,
3920 skc_rcv_saddr) != 4);
3922 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
3923 si->dst_reg, si->src_reg,
3924 offsetof(struct sk_buff, sk));
3925 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
3926 bpf_target_off(struct sock_common,
3930 case offsetof(struct __sk_buff, remote_ip6[0]) ...
3931 offsetof(struct __sk_buff, remote_ip6[3]):
3932 #if IS_ENABLED(CONFIG_IPV6)
3933 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common,
3934 skc_v6_daddr.s6_addr32[0]) != 4);
3937 off -= offsetof(struct __sk_buff, remote_ip6[0]);
3939 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
3940 si->dst_reg, si->src_reg,
3941 offsetof(struct sk_buff, sk));
3942 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
3943 offsetof(struct sock_common,
3944 skc_v6_daddr.s6_addr32[0]) +
3947 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
3950 case offsetof(struct __sk_buff, local_ip6[0]) ...
3951 offsetof(struct __sk_buff, local_ip6[3]):
3952 #if IS_ENABLED(CONFIG_IPV6)
3953 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common,
3954 skc_v6_rcv_saddr.s6_addr32[0]) != 4);
3957 off -= offsetof(struct __sk_buff, local_ip6[0]);
3959 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
3960 si->dst_reg, si->src_reg,
3961 offsetof(struct sk_buff, sk));
3962 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
3963 offsetof(struct sock_common,
3964 skc_v6_rcv_saddr.s6_addr32[0]) +
3967 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
3971 case offsetof(struct __sk_buff, remote_port):
3972 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_dport) != 2);
3974 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
3975 si->dst_reg, si->src_reg,
3976 offsetof(struct sk_buff, sk));
3977 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
3978 bpf_target_off(struct sock_common,
3981 #ifndef __BIG_ENDIAN_BITFIELD
3982 *insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16);
3986 case offsetof(struct __sk_buff, local_port):
3987 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_num) != 2);
3989 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
3990 si->dst_reg, si->src_reg,
3991 offsetof(struct sk_buff, sk));
3992 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
3993 bpf_target_off(struct sock_common,
3994 skc_num, 2, target_size));
3998 return insn - insn_buf;
4001 static u32 sock_filter_convert_ctx_access(enum bpf_access_type type,
4002 const struct bpf_insn *si,
4003 struct bpf_insn *insn_buf,
4004 struct bpf_prog *prog, u32 *target_size)
4006 struct bpf_insn *insn = insn_buf;
4009 case offsetof(struct bpf_sock, bound_dev_if):
4010 BUILD_BUG_ON(FIELD_SIZEOF(struct sock, sk_bound_dev_if) != 4);
4012 if (type == BPF_WRITE)
4013 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
4014 offsetof(struct sock, sk_bound_dev_if));
4016 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
4017 offsetof(struct sock, sk_bound_dev_if));
4020 case offsetof(struct bpf_sock, mark):
4021 BUILD_BUG_ON(FIELD_SIZEOF(struct sock, sk_mark) != 4);
4023 if (type == BPF_WRITE)
4024 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
4025 offsetof(struct sock, sk_mark));
4027 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
4028 offsetof(struct sock, sk_mark));
4031 case offsetof(struct bpf_sock, priority):
4032 BUILD_BUG_ON(FIELD_SIZEOF(struct sock, sk_priority) != 4);
4034 if (type == BPF_WRITE)
4035 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
4036 offsetof(struct sock, sk_priority));
4038 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
4039 offsetof(struct sock, sk_priority));
4042 case offsetof(struct bpf_sock, family):
4043 BUILD_BUG_ON(FIELD_SIZEOF(struct sock, sk_family) != 2);
4045 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
4046 offsetof(struct sock, sk_family));
4049 case offsetof(struct bpf_sock, type):
4050 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
4051 offsetof(struct sock, __sk_flags_offset));
4052 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, SK_FL_TYPE_MASK);
4053 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, SK_FL_TYPE_SHIFT);
4056 case offsetof(struct bpf_sock, protocol):
4057 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
4058 offsetof(struct sock, __sk_flags_offset));
4059 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, SK_FL_PROTO_MASK);
4060 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, SK_FL_PROTO_SHIFT);
4064 return insn - insn_buf;
4067 static u32 tc_cls_act_convert_ctx_access(enum bpf_access_type type,
4068 const struct bpf_insn *si,
4069 struct bpf_insn *insn_buf,
4070 struct bpf_prog *prog, u32 *target_size)
4072 struct bpf_insn *insn = insn_buf;
4075 case offsetof(struct __sk_buff, ifindex):
4076 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev),
4077 si->dst_reg, si->src_reg,
4078 offsetof(struct sk_buff, dev));
4079 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
4080 bpf_target_off(struct net_device, ifindex, 4,
4084 return bpf_convert_ctx_access(type, si, insn_buf, prog,
4088 return insn - insn_buf;
4091 static u32 xdp_convert_ctx_access(enum bpf_access_type type,
4092 const struct bpf_insn *si,
4093 struct bpf_insn *insn_buf,
4094 struct bpf_prog *prog, u32 *target_size)
4096 struct bpf_insn *insn = insn_buf;
4099 case offsetof(struct xdp_md, data):
4100 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data),
4101 si->dst_reg, si->src_reg,
4102 offsetof(struct xdp_buff, data));
4104 case offsetof(struct xdp_md, data_end):
4105 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data_end),
4106 si->dst_reg, si->src_reg,
4107 offsetof(struct xdp_buff, data_end));
4111 return insn - insn_buf;
4114 static u32 sock_ops_convert_ctx_access(enum bpf_access_type type,
4115 const struct bpf_insn *si,
4116 struct bpf_insn *insn_buf,
4117 struct bpf_prog *prog,
4120 struct bpf_insn *insn = insn_buf;
4124 case offsetof(struct bpf_sock_ops, op) ...
4125 offsetof(struct bpf_sock_ops, replylong[3]):
4126 BUILD_BUG_ON(FIELD_SIZEOF(struct bpf_sock_ops, op) !=
4127 FIELD_SIZEOF(struct bpf_sock_ops_kern, op));
4128 BUILD_BUG_ON(FIELD_SIZEOF(struct bpf_sock_ops, reply) !=
4129 FIELD_SIZEOF(struct bpf_sock_ops_kern, reply));
4130 BUILD_BUG_ON(FIELD_SIZEOF(struct bpf_sock_ops, replylong) !=
4131 FIELD_SIZEOF(struct bpf_sock_ops_kern, replylong));
4133 off -= offsetof(struct bpf_sock_ops, op);
4134 off += offsetof(struct bpf_sock_ops_kern, op);
4135 if (type == BPF_WRITE)
4136 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
4139 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
4143 case offsetof(struct bpf_sock_ops, family):
4144 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_family) != 2);
4146 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
4147 struct bpf_sock_ops_kern, sk),
4148 si->dst_reg, si->src_reg,
4149 offsetof(struct bpf_sock_ops_kern, sk));
4150 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
4151 offsetof(struct sock_common, skc_family));
4154 case offsetof(struct bpf_sock_ops, remote_ip4):
4155 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_daddr) != 4);
4157 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
4158 struct bpf_sock_ops_kern, sk),
4159 si->dst_reg, si->src_reg,
4160 offsetof(struct bpf_sock_ops_kern, sk));
4161 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
4162 offsetof(struct sock_common, skc_daddr));
4165 case offsetof(struct bpf_sock_ops, local_ip4):
4166 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_rcv_saddr) != 4);
4168 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
4169 struct bpf_sock_ops_kern, sk),
4170 si->dst_reg, si->src_reg,
4171 offsetof(struct bpf_sock_ops_kern, sk));
4172 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
4173 offsetof(struct sock_common,
4177 case offsetof(struct bpf_sock_ops, remote_ip6[0]) ...
4178 offsetof(struct bpf_sock_ops, remote_ip6[3]):
4179 #if IS_ENABLED(CONFIG_IPV6)
4180 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common,
4181 skc_v6_daddr.s6_addr32[0]) != 4);
4184 off -= offsetof(struct bpf_sock_ops, remote_ip6[0]);
4185 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
4186 struct bpf_sock_ops_kern, sk),
4187 si->dst_reg, si->src_reg,
4188 offsetof(struct bpf_sock_ops_kern, sk));
4189 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
4190 offsetof(struct sock_common,
4191 skc_v6_daddr.s6_addr32[0]) +
4194 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
4198 case offsetof(struct bpf_sock_ops, local_ip6[0]) ...
4199 offsetof(struct bpf_sock_ops, local_ip6[3]):
4200 #if IS_ENABLED(CONFIG_IPV6)
4201 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common,
4202 skc_v6_rcv_saddr.s6_addr32[0]) != 4);
4205 off -= offsetof(struct bpf_sock_ops, local_ip6[0]);
4206 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
4207 struct bpf_sock_ops_kern, sk),
4208 si->dst_reg, si->src_reg,
4209 offsetof(struct bpf_sock_ops_kern, sk));
4210 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
4211 offsetof(struct sock_common,
4212 skc_v6_rcv_saddr.s6_addr32[0]) +
4215 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
4219 case offsetof(struct bpf_sock_ops, remote_port):
4220 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_dport) != 2);
4222 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
4223 struct bpf_sock_ops_kern, sk),
4224 si->dst_reg, si->src_reg,
4225 offsetof(struct bpf_sock_ops_kern, sk));
4226 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
4227 offsetof(struct sock_common, skc_dport));
4228 #ifndef __BIG_ENDIAN_BITFIELD
4229 *insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16);
4233 case offsetof(struct bpf_sock_ops, local_port):
4234 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_num) != 2);
4236 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
4237 struct bpf_sock_ops_kern, sk),
4238 si->dst_reg, si->src_reg,
4239 offsetof(struct bpf_sock_ops_kern, sk));
4240 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
4241 offsetof(struct sock_common, skc_num));
4244 return insn - insn_buf;
4247 static u32 sk_skb_convert_ctx_access(enum bpf_access_type type,
4248 const struct bpf_insn *si,
4249 struct bpf_insn *insn_buf,
4250 struct bpf_prog *prog, u32 *target_size)
4252 struct bpf_insn *insn = insn_buf;
4256 case offsetof(struct __sk_buff, data_end):
4258 off -= offsetof(struct __sk_buff, data_end);
4259 off += offsetof(struct sk_buff, cb);
4260 off += offsetof(struct tcp_skb_cb, bpf.data_end);
4261 *insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg,
4265 return bpf_convert_ctx_access(type, si, insn_buf, prog,
4269 return insn - insn_buf;
4272 const struct bpf_verifier_ops sk_filter_prog_ops = {
4273 .get_func_proto = sk_filter_func_proto,
4274 .is_valid_access = sk_filter_is_valid_access,
4275 .convert_ctx_access = bpf_convert_ctx_access,
4278 const struct bpf_verifier_ops tc_cls_act_prog_ops = {
4279 .get_func_proto = tc_cls_act_func_proto,
4280 .is_valid_access = tc_cls_act_is_valid_access,
4281 .convert_ctx_access = tc_cls_act_convert_ctx_access,
4282 .gen_prologue = tc_cls_act_prologue,
4283 .test_run = bpf_prog_test_run_skb,
4286 const struct bpf_verifier_ops xdp_prog_ops = {
4287 .get_func_proto = xdp_func_proto,
4288 .is_valid_access = xdp_is_valid_access,
4289 .convert_ctx_access = xdp_convert_ctx_access,
4290 .test_run = bpf_prog_test_run_xdp,
4293 const struct bpf_verifier_ops cg_skb_prog_ops = {
4294 .get_func_proto = sk_filter_func_proto,
4295 .is_valid_access = sk_filter_is_valid_access,
4296 .convert_ctx_access = bpf_convert_ctx_access,
4297 .test_run = bpf_prog_test_run_skb,
4300 const struct bpf_verifier_ops lwt_inout_prog_ops = {
4301 .get_func_proto = lwt_inout_func_proto,
4302 .is_valid_access = lwt_is_valid_access,
4303 .convert_ctx_access = bpf_convert_ctx_access,
4304 .test_run = bpf_prog_test_run_skb,
4307 const struct bpf_verifier_ops lwt_xmit_prog_ops = {
4308 .get_func_proto = lwt_xmit_func_proto,
4309 .is_valid_access = lwt_is_valid_access,
4310 .convert_ctx_access = bpf_convert_ctx_access,
4311 .gen_prologue = tc_cls_act_prologue,
4312 .test_run = bpf_prog_test_run_skb,
4315 const struct bpf_verifier_ops cg_sock_prog_ops = {
4316 .get_func_proto = sock_filter_func_proto,
4317 .is_valid_access = sock_filter_is_valid_access,
4318 .convert_ctx_access = sock_filter_convert_ctx_access,
4321 const struct bpf_verifier_ops sock_ops_prog_ops = {
4322 .get_func_proto = sock_ops_func_proto,
4323 .is_valid_access = sock_ops_is_valid_access,
4324 .convert_ctx_access = sock_ops_convert_ctx_access,
4327 const struct bpf_verifier_ops sk_skb_prog_ops = {
4328 .get_func_proto = sk_skb_func_proto,
4329 .is_valid_access = sk_skb_is_valid_access,
4330 .convert_ctx_access = sk_skb_convert_ctx_access,
4331 .gen_prologue = sk_skb_prologue,
4334 int sk_detach_filter(struct sock *sk)
4337 struct sk_filter *filter;
4339 if (sock_flag(sk, SOCK_FILTER_LOCKED))
4342 filter = rcu_dereference_protected(sk->sk_filter,
4343 lockdep_sock_is_held(sk));
4345 RCU_INIT_POINTER(sk->sk_filter, NULL);
4346 sk_filter_uncharge(sk, filter);
4352 EXPORT_SYMBOL_GPL(sk_detach_filter);
4354 int sk_get_filter(struct sock *sk, struct sock_filter __user *ubuf,
4357 struct sock_fprog_kern *fprog;
4358 struct sk_filter *filter;
4362 filter = rcu_dereference_protected(sk->sk_filter,
4363 lockdep_sock_is_held(sk));
4367 /* We're copying the filter that has been originally attached,
4368 * so no conversion/decode needed anymore. eBPF programs that
4369 * have no original program cannot be dumped through this.
4372 fprog = filter->prog->orig_prog;
4378 /* User space only enquires number of filter blocks. */
4382 if (len < fprog->len)
4386 if (copy_to_user(ubuf, fprog->filter, bpf_classic_proglen(fprog)))
4389 /* Instead of bytes, the API requests to return the number