fs/nfs/callback_xdr.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * linux/fs/nfs/callback_xdr.c
   4  *
   5  * Copyright (C) 2004 Trond Myklebust
   6  *
   7  * NFSv4 callback encode/decode procedures
   8  */
   9 #include <linux/kernel.h>
  10 #include <linux/sunrpc/svc.h>
  11 #include <linux/nfs4.h>
  12 #include <linux/nfs_fs.h>
  13 #include <linux/ratelimit.h>
  14 #include <linux/printk.h>
  15 #include <linux/slab.h>
  16 #include <linux/sunrpc/bc_xprt.h>
  17 #include "nfs4_fs.h"
  18 #include "callback.h"
  19 #include "internal.h"
  20 #include "nfs4session.h"
  21 #include "nfs4trace.h"
  22
  23 #define CB_OP_TAGLEN_MAXSZ              (512)
  24 #define CB_OP_HDR_RES_MAXSZ             (2 * 4) // opcode, status
  25 #define CB_OP_GETATTR_BITMAP_MAXSZ      (4 * 4) // bitmap length, 3 bitmaps
  26 #define CB_OP_GETATTR_RES_MAXSZ         (CB_OP_HDR_RES_MAXSZ + \
  27                                          CB_OP_GETATTR_BITMAP_MAXSZ + \
  28                                          /* change, size, ctime, mtime */\
  29                                          (2 + 2 + 3 + 3) * 4)
  30 #define CB_OP_RECALL_RES_MAXSZ          (CB_OP_HDR_RES_MAXSZ)
  31
  32 #if defined(CONFIG_NFS_V4_1)
  33 #define CB_OP_LAYOUTRECALL_RES_MAXSZ    (CB_OP_HDR_RES_MAXSZ)
  34 #define CB_OP_DEVICENOTIFY_RES_MAXSZ    (CB_OP_HDR_RES_MAXSZ)
  35 #define CB_OP_SEQUENCE_RES_MAXSZ        (CB_OP_HDR_RES_MAXSZ + \
  36                                          NFS4_MAX_SESSIONID_LEN + \
  37                                          (1 + 3) * 4) // seqid, 3 slotids
  38 #define CB_OP_RECALLANY_RES_MAXSZ       (CB_OP_HDR_RES_MAXSZ)
  39 #define CB_OP_RECALLSLOT_RES_MAXSZ      (CB_OP_HDR_RES_MAXSZ)
  40 #define CB_OP_NOTIFY_LOCK_RES_MAXSZ     (CB_OP_HDR_RES_MAXSZ)
  41 #endif /* CONFIG_NFS_V4_1 */
  42 #ifdef CONFIG_NFS_V4_2
  43 #define CB_OP_OFFLOAD_RES_MAXSZ         (CB_OP_HDR_RES_MAXSZ)
  44 #endif /* CONFIG_NFS_V4_2 */
  45
  46 #define NFSDBG_FACILITY NFSDBG_CALLBACK
  47
  48 /* Internal error code */
  49 #define NFS4ERR_RESOURCE_HDR    11050
  50
  51 struct callback_op {
  52         __be32 (*process_op)(void *, void *, struct cb_process_state *);
  53         __be32 (*decode_args)(struct svc_rqst *, struct xdr_stream *, void *);
  54         __be32 (*encode_res)(struct svc_rqst *, struct xdr_stream *,
  55                         const void *);
  56         long res_maxsize;
  57 };
  58
  59 static struct callback_op callback_ops[];
  60
  61 static __be32 nfs4_callback_null(struct svc_rqst *rqstp)
  62 {
  63         return htonl(NFS4_OK);
  64 }
  65
  66 /*
  67  * svc_process_common() looks for an XDR encoder to know when
  68  * not to drop a Reply.
  69  */
  70 static bool nfs4_encode_void(struct svc_rqst *rqstp, struct xdr_stream *xdr)
  71 {
  72         return true;
  73 }
  74
  75 static __be32 decode_string(struct xdr_stream *xdr, unsigned int *len,
  76                 const char **str, size_t maxlen)
  77 {
  78         ssize_t err;
  79
  80         err = xdr_stream_decode_opaque_inline(xdr, (void **)str, maxlen);
  81         if (err < 0)
  82                 return cpu_to_be32(NFS4ERR_RESOURCE);
  83         *len = err;
  84         return 0;
  85 }
  86
  87 static __be32 decode_fh(struct xdr_stream *xdr, struct nfs_fh *fh)
  88 {
  89         __be32 *p;
  90
  91         p = xdr_inline_decode(xdr, 4);
  92         if (unlikely(p == NULL))
  93                 return htonl(NFS4ERR_RESOURCE);
  94         fh->size = ntohl(*p);
  95         if (fh->size > NFS4_FHSIZE)
  96                 return htonl(NFS4ERR_BADHANDLE);
  97         p = xdr_inline_decode(xdr, fh->size);
  98         if (unlikely(p == NULL))
  99                 return htonl(NFS4ERR_RESOURCE);
 100         memcpy(&fh->data[0], p, fh->size);
 101         memset(&fh->data[fh->size], 0, sizeof(fh->data) - fh->size);
 102         return 0;
 103 }
 104
 105 static __be32 decode_bitmap(struct xdr_stream *xdr, uint32_t *bitmap)
 106 {
 107         __be32 *p;
 108         unsigned int attrlen;
 109
 110         p = xdr_inline_decode(xdr, 4);
 111         if (unlikely(p == NULL))
 112                 return htonl(NFS4ERR_RESOURCE);
 113         attrlen = ntohl(*p);
 114         p = xdr_inline_decode(xdr, attrlen << 2);
 115         if (unlikely(p == NULL))
 116                 return htonl(NFS4ERR_RESOURCE);
 117         if (likely(attrlen > 0))
 118                 bitmap[0] = ntohl(*p++);
 119         if (attrlen > 1)
 120                 bitmap[1] = ntohl(*p);
 121         return 0;
 122 }
 123
 124 static __be32 decode_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
 125 {
 126         __be32 *p;
 127
 128         p = xdr_inline_decode(xdr, NFS4_STATEID_SIZE);
 129         if (unlikely(p == NULL))
 130                 return htonl(NFS4ERR_RESOURCE);
 131         memcpy(stateid->data, p, NFS4_STATEID_SIZE);
 132         return 0;
 133 }
 134
 135 static __be32 decode_delegation_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
 136 {
 137         stateid->type = NFS4_DELEGATION_STATEID_TYPE;
 138         return decode_stateid(xdr, stateid);
 139 }
 140
 141 static __be32 decode_compound_hdr_arg(struct xdr_stream *xdr, struct cb_compound_hdr_arg *hdr)
 142 {
 143         __be32 *p;
 144         __be32 status;
 145
 146         status = decode_string(xdr, &hdr->taglen, &hdr->tag, CB_OP_TAGLEN_MAXSZ);
 147         if (unlikely(status != 0))
 148                 return status;
 149         p = xdr_inline_decode(xdr, 12);
 150         if (unlikely(p == NULL))
 151                 return htonl(NFS4ERR_RESOURCE);
 152         hdr->minorversion = ntohl(*p++);
 153         /* Check for minor version support */
 154         if (hdr->minorversion <= NFS4_MAX_MINOR_VERSION) {
 155                 hdr->cb_ident = ntohl(*p++); /* ignored by v4.1 and v4.2 */
 156         } else {
 157                 pr_warn_ratelimited("NFS: %s: NFSv4 server callback with "
 158                         "illegal minor version %u!\n",
 159                         __func__, hdr->minorversion);
 160                 return htonl(NFS4ERR_MINOR_VERS_MISMATCH);
 161         }
 162         hdr->nops = ntohl(*p);
 163         return 0;
 164 }
 165
 166 static __be32 decode_op_hdr(struct xdr_stream *xdr, unsigned int *op)
 167 {
 168         __be32 *p;
 169         p = xdr_inline_decode(xdr, 4);
 170         if (unlikely(p == NULL))
 171                 return htonl(NFS4ERR_RESOURCE_HDR);
 172         *op = ntohl(*p);
 173         return 0;
 174 }
 175
 176 static __be32 decode_getattr_args(struct svc_rqst *rqstp,
 177                 struct xdr_stream *xdr, void *argp)
 178 {
 179         struct cb_getattrargs *args = argp;
 180         __be32 status;
 181
 182         status = decode_fh(xdr, &args->fh);
 183         if (unlikely(status != 0))
 184                 return status;
 185         return decode_bitmap(xdr, args->bitmap);
 186 }
 187
 188 static __be32 decode_recall_args(struct svc_rqst *rqstp,
 189                 struct xdr_stream *xdr, void *argp)
 190 {
 191         struct cb_recallargs *args = argp;
 192         __be32 *p;
 193         __be32 status;
 194
 195         status = decode_delegation_stateid(xdr, &args->stateid);
 196         if (unlikely(status != 0))
 197                 return status;
 198         p = xdr_inline_decode(xdr, 4);
 199         if (unlikely(p == NULL))
 200                 return htonl(NFS4ERR_RESOURCE);
 201         args->truncate = ntohl(*p);
 202         return decode_fh(xdr, &args->fh);
 203 }
 204
 205 #if defined(CONFIG_NFS_V4_1)
 206 static __be32 decode_layout_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
 207 {
 208         stateid->type = NFS4_LAYOUT_STATEID_TYPE;
 209         return decode_stateid(xdr, stateid);
 210 }
 211
 212 static __be32 decode_layoutrecall_args(struct svc_rqst *rqstp,
 213                                        struct xdr_stream *xdr, void *argp)
 214 {
 215         struct cb_layoutrecallargs *args = argp;
 216         __be32 *p;
 217         __be32 status = 0;
 218         uint32_t iomode;
 219
 220         p = xdr_inline_decode(xdr, 4 * sizeof(uint32_t));
 221         if (unlikely(p == NULL))
 222                 return htonl(NFS4ERR_BADXDR);
 223
 224         args->cbl_layout_type = ntohl(*p++);
 225         /* Depite the spec's xdr, iomode really belongs in the FILE switch,
 226          * as it is unusable and ignored with the other types.
 227          */
 228         iomode = ntohl(*p++);
 229         args->cbl_layoutchanged = ntohl(*p++);
 230         args->cbl_recall_type = ntohl(*p++);
 231
 232         if (args->cbl_recall_type == RETURN_FILE) {
 233                 args->cbl_range.iomode = iomode;
 234                 status = decode_fh(xdr, &args->cbl_fh);
 235                 if (unlikely(status != 0))
 236                         return status;
 237
 238                 p = xdr_inline_decode(xdr, 2 * sizeof(uint64_t));
 239                 if (unlikely(p == NULL))
 240                         return htonl(NFS4ERR_BADXDR);
 241                 p = xdr_decode_hyper(p, &args->cbl_range.offset);
 242                 p = xdr_decode_hyper(p, &args->cbl_range.length);
 243                 return decode_layout_stateid(xdr, &args->cbl_stateid);
 244         } else if (args->cbl_recall_type == RETURN_FSID) {
 245                 p = xdr_inline_decode(xdr, 2 * sizeof(uint64_t));
 246                 if (unlikely(p == NULL))
 247                         return htonl(NFS4ERR_BADXDR);
 248                 p = xdr_decode_hyper(p, &args->cbl_fsid.major);
 249                 p = xdr_decode_hyper(p, &args->cbl_fsid.minor);
 250         } else if (args->cbl_recall_type != RETURN_ALL)
 251                 return htonl(NFS4ERR_BADXDR);
 252         return 0;
 253 }
 254
 255 static
 256 __be32 decode_devicenotify_args(struct svc_rqst *rqstp,
 257                                 struct xdr_stream *xdr,
 258                                 void *argp)
 259 {
 260         struct cb_devicenotifyargs *args = argp;
 261         uint32_t tmp, n, i;
 262         __be32 *p;
 263         __be32 status = 0;
 264
 265         /* Num of device notifications */
 266         p = xdr_inline_decode(xdr, sizeof(uint32_t));
 267         if (unlikely(p == NULL)) {
 268                 status = htonl(NFS4ERR_BADXDR);
 269                 goto out;
 270         }
 271         n = ntohl(*p++);
 272         if (n == 0)
 273                 goto out;
 274
 275         args->devs = kmalloc_array(n, sizeof(*args->devs), GFP_KERNEL);
 276         if (!args->devs) {
 277                 status = htonl(NFS4ERR_DELAY);
 278                 goto out;
 279         }
 280
 281         /* Decode each dev notification */
 282         for (i = 0; i < n; i++) {
 283                 struct cb_devicenotifyitem *dev = &args->devs[i];
 284
 285                 p = xdr_inline_decode(xdr, (4 * sizeof(uint32_t)) +
 286                                       NFS4_DEVICEID4_SIZE);
 287                 if (unlikely(p == NULL)) {
 288                         status = htonl(NFS4ERR_BADXDR);
 289                         goto err;
 290                 }
 291
 292                 tmp = ntohl(*p++);      /* bitmap size */
 293                 if (tmp != 1) {
 294                         status = htonl(NFS4ERR_INVAL);
 295                         goto err;
 296                 }
 297                 dev->cbd_notify_type = ntohl(*p++);
 298                 if (dev->cbd_notify_type != NOTIFY_DEVICEID4_CHANGE &&
 299                     dev->cbd_notify_type != NOTIFY_DEVICEID4_DELETE) {
 300                         status = htonl(NFS4ERR_INVAL);
 301                         goto err;
 302                 }
 303
 304                 tmp = ntohl(*p++);      /* opaque size */
 305                 if (((dev->cbd_notify_type == NOTIFY_DEVICEID4_CHANGE) &&
 306                      (tmp != NFS4_DEVICEID4_SIZE + 8)) ||
 307                     ((dev->cbd_notify_type == NOTIFY_DEVICEID4_DELETE) &&
 308                      (tmp != NFS4_DEVICEID4_SIZE + 4))) {
 309                         status = htonl(NFS4ERR_INVAL);
 310                         goto err;
 311                 }
 312                 dev->cbd_layout_type = ntohl(*p++);
 313                 memcpy(dev->cbd_dev_id.data, p, NFS4_DEVICEID4_SIZE);
 314                 p += XDR_QUADLEN(NFS4_DEVICEID4_SIZE);
 315
 316                 if (dev->cbd_layout_type == NOTIFY_DEVICEID4_CHANGE) {
 317                         p = xdr_inline_decode(xdr, sizeof(uint32_t));
 318                         if (unlikely(p == NULL)) {
 319                                 status = htonl(NFS4ERR_BADXDR);
 320                                 goto err;
 321                         }
 322                         dev->cbd_immediate = ntohl(*p++);
 323                 } else {
 324                         dev->cbd_immediate = 0;
 325                 }
 326
 327                 dprintk("%s: type %d layout 0x%x immediate %d\n",
 328                         __func__, dev->cbd_notify_type, dev->cbd_layout_type,
 329                         dev->cbd_immediate);
 330         }
 331         args->ndevs = n;
 332         dprintk("%s: ndevs %d\n", __func__, args->ndevs);
 333         return 0;
 334 err:
 335         kfree(args->devs);
 336 out:
 337         args->devs = NULL;
 338         args->ndevs = 0;
 339         dprintk("%s: status %d ndevs %d\n",
 340                 __func__, ntohl(status), args->ndevs);
 341         return status;
 342 }
 343
 344 static __be32 decode_sessionid(struct xdr_stream *xdr,
 345                                  struct nfs4_sessionid *sid)
 346 {
 347         __be32 *p;
 348
 349         p = xdr_inline_decode(xdr, NFS4_MAX_SESSIONID_LEN);
 350         if (unlikely(p == NULL))
 351                 return htonl(NFS4ERR_RESOURCE);
 352
 353         memcpy(sid->data, p, NFS4_MAX_SESSIONID_LEN);
 354         return 0;
 355 }
 356
 357 static __be32 decode_rc_list(struct xdr_stream *xdr,
 358                                struct referring_call_list *rc_list)
 359 {
 360         __be32 *p;
 361         int i;
 362         __be32 status;
 363
 364         status = decode_sessionid(xdr, &rc_list->rcl_sessionid);
 365         if (status)
 366                 goto out;
 367
 368         status = htonl(NFS4ERR_RESOURCE);
 369         p = xdr_inline_decode(xdr, sizeof(uint32_t));
 370         if (unlikely(p == NULL))
 371                 goto out;
 372
 373         rc_list->rcl_nrefcalls = ntohl(*p++);
 374         if (rc_list->rcl_nrefcalls) {
 375                 p = xdr_inline_decode(xdr,
 376                              rc_list->rcl_nrefcalls * 2 * sizeof(uint32_t));
 377                 if (unlikely(p == NULL))
 378                         goto out;
 379                 rc_list->rcl_refcalls = kmalloc_array(rc_list->rcl_nrefcalls,
 380                                                 sizeof(*rc_list->rcl_refcalls),
 381                                                 GFP_KERNEL);
 382                 if (unlikely(rc_list->rcl_refcalls == NULL))
 383                         goto out;
 384                 for (i = 0; i < rc_list->rcl_nrefcalls; i++) {
 385                         rc_list->rcl_refcalls[i].rc_sequenceid = ntohl(*p++);
 386                         rc_list->rcl_refcalls[i].rc_slotid = ntohl(*p++);
 387                 }
 388         }
 389         status = 0;
 390
 391 out:
 392         return status;
 393 }
 394
 395 static __be32 decode_cb_sequence_args(struct svc_rqst *rqstp,
 396                                         struct xdr_stream *xdr,
 397                                         void *argp)
 398 {
 399         struct cb_sequenceargs *args = argp;
 400         __be32 *p;
 401         int i;
 402         __be32 status;
 403
 404         status = decode_sessionid(xdr, &args->csa_sessionid);
 405         if (status)
 406                 return status;
 407
 408         p = xdr_inline_decode(xdr, 5 * sizeof(uint32_t));
 409         if (unlikely(p == NULL))
 410                 return htonl(NFS4ERR_RESOURCE);
 411
 412         args->csa_addr = svc_addr(rqstp);
 413         args->csa_sequenceid = ntohl(*p++);
 414         args->csa_slotid = ntohl(*p++);
 415         args->csa_highestslotid = ntohl(*p++);
 416         args->csa_cachethis = ntohl(*p++);
 417         args->csa_nrclists = ntohl(*p++);
 418         args->csa_rclists = NULL;
 419         if (args->csa_nrclists) {
 420                 args->csa_rclists = kmalloc_array(args->csa_nrclists,
 421                                                   sizeof(*args->csa_rclists),
 422                                                   GFP_KERNEL);
 423                 if (unlikely(args->csa_rclists == NULL))
 424                         return htonl(NFS4ERR_RESOURCE);
 425
 426                 for (i = 0; i < args->csa_nrclists; i++) {
 427                         status = decode_rc_list(xdr, &args->csa_rclists[i]);
 428                         if (status) {
 429                                 args->csa_nrclists = i;
 430                                 goto out_free;
 431                         }
 432                 }
 433         }
 434         return 0;
 435
 436 out_free:
 437         for (i = 0; i < args->csa_nrclists; i++)
 438                 kfree(args->csa_rclists[i].rcl_refcalls);
 439         kfree(args->csa_rclists);
 440         return status;
 441 }
 442
 443 static __be32 decode_recallany_args(struct svc_rqst *rqstp,
 444                                       struct xdr_stream *xdr,
 445                                       void *argp)
 446 {
 447         struct cb_recallanyargs *args = argp;
 448         uint32_t bitmap[2];
 449         __be32 *p, status;
 450
 451         p = xdr_inline_decode(xdr, 4);
 452         if (unlikely(p == NULL))
 453                 return htonl(NFS4ERR_BADXDR);
 454         args->craa_objs_to_keep = ntohl(*p++);
 455         status = decode_bitmap(xdr, bitmap);
 456         if (unlikely(status))
 457                 return status;
 458         args->craa_type_mask = bitmap[0];
 459
 460         return 0;
 461 }
 462
 463 static __be32 decode_recallslot_args(struct svc_rqst *rqstp,
 464                                         struct xdr_stream *xdr,
 465                                         void *argp)
 466 {
 467         struct cb_recallslotargs *args = argp;
 468         __be32 *p;
 469
 470         p = xdr_inline_decode(xdr, 4);
 471         if (unlikely(p == NULL))
 472                 return htonl(NFS4ERR_BADXDR);
 473         args->crsa_target_highest_slotid = ntohl(*p++);
 474         return 0;
 475 }
 476
 477 static __be32 decode_lockowner(struct xdr_stream *xdr, struct cb_notify_lock_args *args)
 478 {
 479         __be32          *p;
 480         unsigned int    len;
 481
 482         p = xdr_inline_decode(xdr, 12);
 483         if (unlikely(p == NULL))
 484                 return htonl(NFS4ERR_BADXDR);
 485
 486         p = xdr_decode_hyper(p, &args->cbnl_owner.clientid);
 487         len = be32_to_cpu(*p);
 488
 489         p = xdr_inline_decode(xdr, len);
 490         if (unlikely(p == NULL))
 491                 return htonl(NFS4ERR_BADXDR);
 492
 493         /* Only try to decode if the length is right */
 494         if (len == 20) {
 495                 p += 2; /* skip "lock id:" */
 496                 args->cbnl_owner.s_dev = be32_to_cpu(*p++);
 497                 xdr_decode_hyper(p, &args->cbnl_owner.id);
 498                 args->cbnl_valid = true;
 499         } else {
 500                 args->cbnl_owner.s_dev = 0;
 501                 args->cbnl_owner.id = 0;
 502                 args->cbnl_valid = false;
 503         }
 504         return 0;
 505 }
 506
 507 static __be32 decode_notify_lock_args(struct svc_rqst *rqstp,
 508                 struct xdr_stream *xdr, void *argp)
 509 {
 510         struct cb_notify_lock_args *args = argp;
 511         __be32 status;
 512
 513         status = decode_fh(xdr, &args->cbnl_fh);
 514         if (unlikely(status != 0))
 515                 return status;
 516         return decode_lockowner(xdr, args);
 517 }
 518
 519 #endif /* CONFIG_NFS_V4_1 */
 520 #ifdef CONFIG_NFS_V4_2
 521 static __be32 decode_write_response(struct xdr_stream *xdr,
 522                                         struct cb_offloadargs *args)
 523 {
 524         __be32 *p;
 525
 526         /* skip the always zero field */
 527         p = xdr_inline_decode(xdr, 4);
 528         if (unlikely(!p))
 529                 goto out;
 530         p++;
 531
 532         /* decode count, stable_how, verifier */
 533         p = xdr_inline_decode(xdr, 8 + 4);
 534         if (unlikely(!p))
 535                 goto out;
 536         p = xdr_decode_hyper(p, &args->wr_count);
 537         args->wr_writeverf.committed = be32_to_cpup(p);
 538         p = xdr_inline_decode(xdr, NFS4_VERIFIER_SIZE);
 539         if (likely(p)) {
 540                 memcpy(&args->wr_writeverf.verifier.data[0], p,
 541                         NFS4_VERIFIER_SIZE);
 542                 return 0;
 543         }
 544 out:
 545         return htonl(NFS4ERR_RESOURCE);
 546 }
 547
 548 static __be32 decode_offload_args(struct svc_rqst *rqstp,
 549                                         struct xdr_stream *xdr,
 550                                         void *data)
 551 {
 552         struct cb_offloadargs *args = data;
 553         __be32 *p;
 554         __be32 status;
 555
 556         /* decode fh */
 557         status = decode_fh(xdr, &args->coa_fh);
 558         if (unlikely(status != 0))
 559                 return status;
 560
 561         /* decode stateid */
 562         status = decode_stateid(xdr, &args->coa_stateid);
 563         if (unlikely(status != 0))
 564                 return status;
 565
 566         /* decode status */
 567         p = xdr_inline_decode(xdr, 4);
 568         if (unlikely(!p))
 569                 goto out;
 570         args->error = ntohl(*p++);
 571         if (!args->error) {
 572                 status = decode_write_response(xdr, args);
 573                 if (unlikely(status != 0))
 574                         return status;
 575         } else {
 576                 p = xdr_inline_decode(xdr, 8);
 577                 if (unlikely(!p))
 578                         goto out;
 579                 p = xdr_decode_hyper(p, &args->wr_count);
 580         }
 581         return 0;
 582 out:
 583         return htonl(NFS4ERR_RESOURCE);
 584 }
 585 #endif /* CONFIG_NFS_V4_2 */
 586 static __be32 encode_string(struct xdr_stream *xdr, unsigned int len, const char *str)
 587 {
 588         if (unlikely(xdr_stream_encode_opaque(xdr, str, len) < 0))
 589                 return cpu_to_be32(NFS4ERR_RESOURCE);
 590         return 0;
 591 }
 592
 593 static __be32 encode_attr_bitmap(struct xdr_stream *xdr, const uint32_t *bitmap, size_t sz)
 594 {
 595         if (xdr_stream_encode_uint32_array(xdr, bitmap, sz) < 0)
 596                 return cpu_to_be32(NFS4ERR_RESOURCE);
 597         return 0;
 598 }
 599
 600 static __be32 encode_attr_change(struct xdr_stream *xdr, const uint32_t *bitmap, uint64_t change)
 601 {
 602         __be32 *p;
 603
 604         if (!(bitmap[0] & FATTR4_WORD0_CHANGE))
 605                 return 0;
 606         p = xdr_reserve_space(xdr, 8);
 607         if (unlikely(!p))
 608                 return htonl(NFS4ERR_RESOURCE);
 609         p = xdr_encode_hyper(p, change);
 610         return 0;
 611 }
 612
 613 static __be32 encode_attr_size(struct xdr_stream *xdr, const uint32_t *bitmap, uint64_t size)
 614 {
 615         __be32 *p;
 616
 617         if (!(bitmap[0] & FATTR4_WORD0_SIZE))
 618                 return 0;
 619         p = xdr_reserve_space(xdr, 8);
 620         if (unlikely(!p))
 621                 return htonl(NFS4ERR_RESOURCE);
 622         p = xdr_encode_hyper(p, size);
 623         return 0;
 624 }
 625
 626 static __be32 encode_attr_time(struct xdr_stream *xdr, const struct timespec64 *time)
 627 {
 628         __be32 *p;
 629
 630         p = xdr_reserve_space(xdr, 12);
 631         if (unlikely(!p))
 632                 return htonl(NFS4ERR_RESOURCE);
 633         p = xdr_encode_hyper(p, time->tv_sec);
 634         *p = htonl(time->tv_nsec);
 635         return 0;
 636 }
 637
 638 static __be32 encode_attr_ctime(struct xdr_stream *xdr, const uint32_t *bitmap, const struct timespec64 *time)
 639 {
 640         if (!(bitmap[1] & FATTR4_WORD1_TIME_METADATA))
 641                 return 0;
 642         return encode_attr_time(xdr,time);
 643 }
 644
 645 static __be32 encode_attr_mtime(struct xdr_stream *xdr, const uint32_t *bitmap, const struct timespec64 *time)
 646 {
 647         if (!(bitmap[1] & FATTR4_WORD1_TIME_MODIFY))
 648                 return 0;
 649         return encode_attr_time(xdr,time);
 650 }
 651
 652 static __be32 encode_compound_hdr_res(struct xdr_stream *xdr, struct cb_compound_hdr_res *hdr)
 653 {
 654         __be32 status;
 655
 656         hdr->status = xdr_reserve_space(xdr, 4);
 657         if (unlikely(hdr->status == NULL))
 658                 return htonl(NFS4ERR_RESOURCE);
 659         status = encode_string(xdr, hdr->taglen, hdr->tag);
 660         if (unlikely(status != 0))
 661                 return status;
 662         hdr->nops = xdr_reserve_space(xdr, 4);
 663         if (unlikely(hdr->nops == NULL))
 664                 return htonl(NFS4ERR_RESOURCE);
 665         return 0;
 666 }
 667
 668 static __be32 encode_op_hdr(struct xdr_stream *xdr, uint32_t op, __be32 res)
 669 {
 670         __be32 *p;
 671
 672         p = xdr_reserve_space(xdr, 8);
 673         if (unlikely(p == NULL))
 674                 return htonl(NFS4ERR_RESOURCE_HDR);
 675         *p++ = htonl(op);
 676         *p = res;
 677         return 0;
 678 }
 679
 680 static __be32 encode_getattr_res(struct svc_rqst *rqstp, struct xdr_stream *xdr,
 681                 const void *resp)
 682 {
 683         const struct cb_getattrres *res = resp;
 684         __be32 *savep = NULL;
 685         __be32 status = res->status;
 686
 687         if (unlikely(status != 0))
 688                 goto out;
 689         status = encode_attr_bitmap(xdr, res->bitmap, ARRAY_SIZE(res->bitmap));
 690         if (unlikely(status != 0))
 691                 goto out;
 692         status = cpu_to_be32(NFS4ERR_RESOURCE);
 693         savep = xdr_reserve_space(xdr, sizeof(*savep));
 694         if (unlikely(!savep))
 695                 goto out;
 696         status = encode_attr_change(xdr, res->bitmap, res->change_attr);
 697         if (unlikely(status != 0))
 698                 goto out;
 699         status = encode_attr_size(xdr, res->bitmap, res->size);
 700         if (unlikely(status != 0))
 701                 goto out;
 702         status = encode_attr_ctime(xdr, res->bitmap, &res->ctime);
 703         if (unlikely(status != 0))
 704                 goto out;
 705         status = encode_attr_mtime(xdr, res->bitmap, &res->mtime);
 706         *savep = htonl((unsigned int)((char *)xdr->p - (char *)(savep+1)));
 707 out:
 708         return status;
 709 }
 710
 711 #if defined(CONFIG_NFS_V4_1)
 712
 713 static __be32 encode_sessionid(struct xdr_stream *xdr,
 714                                  const struct nfs4_sessionid *sid)
 715 {
 716         __be32 *p;
 717
 718         p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN);
 719         if (unlikely(p == NULL))
 720                 return htonl(NFS4ERR_RESOURCE);
 721
 722         memcpy(p, sid, NFS4_MAX_SESSIONID_LEN);
 723         return 0;
 724 }
 725
 726 static __be32 encode_cb_sequence_res(struct svc_rqst *rqstp,
 727                                        struct xdr_stream *xdr,
 728                                        const void *resp)
 729 {
 730         const struct cb_sequenceres *res = resp;
 731         __be32 *p;
 732         __be32 status = res->csr_status;
 733
 734         if (unlikely(status != 0))
 735                 return status;
 736
 737         status = encode_sessionid(xdr, &res->csr_sessionid);
 738         if (status)
 739                 return status;
 740
 741         p = xdr_reserve_space(xdr, 4 * sizeof(uint32_t));
 742         if (unlikely(p == NULL))
 743                 return htonl(NFS4ERR_RESOURCE);
 744
 745         *p++ = htonl(res->csr_sequenceid);
 746         *p++ = htonl(res->csr_slotid);
 747         *p++ = htonl(res->csr_highestslotid);
 748         *p++ = htonl(res->csr_target_highestslotid);
 749         return 0;
 750 }
 751
 752 static __be32
 753 preprocess_nfs41_op(int nop, unsigned int op_nr, struct callback_op **op)
 754 {
 755         if (op_nr == OP_CB_SEQUENCE) {
 756                 if (nop != 0)
 757                         return htonl(NFS4ERR_SEQUENCE_POS);
 758         } else {
 759                 if (nop == 0)
 760                         return htonl(NFS4ERR_OP_NOT_IN_SESSION);
 761         }
 762
 763         switch (op_nr) {
 764         case OP_CB_GETATTR:
 765         case OP_CB_RECALL:
 766         case OP_CB_SEQUENCE:
 767         case OP_CB_RECALL_ANY:
 768         case OP_CB_RECALL_SLOT:
 769         case OP_CB_LAYOUTRECALL:
 770         case OP_CB_NOTIFY_DEVICEID:
 771         case OP_CB_NOTIFY_LOCK:
 772                 *op = &callback_ops[op_nr];
 773                 break;
 774
 775         case OP_CB_NOTIFY:
 776         case OP_CB_PUSH_DELEG:
 777         case OP_CB_RECALLABLE_OBJ_AVAIL:
 778         case OP_CB_WANTS_CANCELLED:
 779                 return htonl(NFS4ERR_NOTSUPP);
 780
 781         default:
 782                 return htonl(NFS4ERR_OP_ILLEGAL);
 783         }
 784
 785         return htonl(NFS_OK);
 786 }
 787
 788 static void nfs4_callback_free_slot(struct nfs4_session *session,
 789                 struct nfs4_slot *slot)
 790 {
 791         struct nfs4_slot_table *tbl = &session->bc_slot_table;
 792
 793         spin_lock(&tbl->slot_tbl_lock);
 794         /*
 795          * Let the state manager know callback processing done.
 796          * A single slot, so highest used slotid is either 0 or -1
 797          */
 798         nfs4_free_slot(tbl, slot);
 799         spin_unlock(&tbl->slot_tbl_lock);
 800 }
 801
 802 static void nfs4_cb_free_slot(struct cb_process_state *cps)
 803 {
 804         if (cps->slot) {
 805                 nfs4_callback_free_slot(cps->clp->cl_session, cps->slot);
 806                 cps->slot = NULL;
 807         }
 808 }
 809
 810 #else /* CONFIG_NFS_V4_1 */
 811
 812 static __be32
 813 preprocess_nfs41_op(int nop, unsigned int op_nr, struct callback_op **op)
 814 {
 815         return htonl(NFS4ERR_MINOR_VERS_MISMATCH);
 816 }
 817
 818 static void nfs4_cb_free_slot(struct cb_process_state *cps)
 819 {
 820 }
 821 #endif /* CONFIG_NFS_V4_1 */
 822
 823 #ifdef CONFIG_NFS_V4_2
 824 static __be32
 825 preprocess_nfs42_op(int nop, unsigned int op_nr, struct callback_op **op)
 826 {
 827         __be32 status = preprocess_nfs41_op(nop, op_nr, op);
 828         if (status != htonl(NFS4ERR_OP_ILLEGAL))
 829                 return status;
 830
 831         if (op_nr == OP_CB_OFFLOAD) {
 832                 *op = &callback_ops[op_nr];
 833                 return htonl(NFS_OK);
 834         } else
 835                 return htonl(NFS4ERR_NOTSUPP);
 836         return htonl(NFS4ERR_OP_ILLEGAL);
 837 }
 838 #else /* CONFIG_NFS_V4_2 */
 839 static __be32
 840 preprocess_nfs42_op(int nop, unsigned int op_nr, struct callback_op **op)
 841 {
 842         return htonl(NFS4ERR_MINOR_VERS_MISMATCH);
 843 }
 844 #endif /* CONFIG_NFS_V4_2 */
 845
 846 static __be32
 847 preprocess_nfs4_op(unsigned int op_nr, struct callback_op **op)
 848 {
 849         switch (op_nr) {
 850         case OP_CB_GETATTR:
 851         case OP_CB_RECALL:
 852                 *op = &callback_ops[op_nr];
 853                 break;
 854         default:
 855                 return htonl(NFS4ERR_OP_ILLEGAL);
 856         }
 857
 858         return htonl(NFS_OK);
 859 }
 860
 861 static __be32 process_op(int nop, struct svc_rqst *rqstp,
 862                          struct cb_process_state *cps)
 863 {
 864         struct xdr_stream *xdr_out = &rqstp->rq_res_stream;
 865         struct callback_op *op = &callback_ops[0];
 866         unsigned int op_nr;
 867         __be32 status;
 868         long maxlen;
 869         __be32 res;
 870
 871         status = decode_op_hdr(&rqstp->rq_arg_stream, &op_nr);
 872         if (unlikely(status))
 873                 return status;
 874
 875         switch (cps->minorversion) {
 876         case 0:
 877                 status = preprocess_nfs4_op(op_nr, &op);
 878                 break;
 879         case 1:
 880                 status = preprocess_nfs41_op(nop, op_nr, &op);
 881                 break;
 882         case 2:
 883                 status = preprocess_nfs42_op(nop, op_nr, &op);
 884                 break;
 885         default:
 886                 status = htonl(NFS4ERR_MINOR_VERS_MISMATCH);
 887         }
 888
 889         if (status == htonl(NFS4ERR_OP_ILLEGAL))
 890                 op_nr = OP_CB_ILLEGAL;
 891         if (status)
 892                 goto encode_hdr;
 893
 894         if (cps->drc_status) {
 895                 status = cps->drc_status;
 896                 goto encode_hdr;
 897         }
 898
 899         maxlen = xdr_out->end - xdr_out->p;
 900         if (maxlen > 0 && maxlen < PAGE_SIZE) {
 901                 status = op->decode_args(rqstp, &rqstp->rq_arg_stream,
 902                                          rqstp->rq_argp);
 903                 if (likely(status == 0))
 904                         status = op->process_op(rqstp->rq_argp, rqstp->rq_resp,
 905                                                 cps);
 906         } else
 907                 status = htonl(NFS4ERR_RESOURCE);
 908
 909 encode_hdr:
 910         res = encode_op_hdr(xdr_out, op_nr, status);
 911         if (unlikely(res))
 912                 return res;
 913         if (op->encode_res != NULL && status == 0)
 914                 status = op->encode_res(rqstp, xdr_out, rqstp->rq_resp);
 915         return status;
 916 }
 917
 918 /*
 919  * Decode, process and encode a COMPOUND
 920  */
 921 static __be32 nfs4_callback_compound(struct svc_rqst *rqstp)
 922 {
 923         struct cb_compound_hdr_arg hdr_arg = { 0 };
 924         struct cb_compound_hdr_res hdr_res = { NULL };
 925         struct cb_process_state cps = {
 926                 .drc_status = 0,
 927                 .clp = NULL,
 928                 .net = SVC_NET(rqstp),
 929         };
 930         unsigned int nops = 0;
 931         __be32 status;
 932
 933         status = decode_compound_hdr_arg(&rqstp->rq_arg_stream, &hdr_arg);
 934         if (status == htonl(NFS4ERR_RESOURCE))
 935                 return rpc_garbage_args;
 936
 937         if (hdr_arg.minorversion == 0) {
 938                 cps.clp = nfs4_find_client_ident(SVC_NET(rqstp), hdr_arg.cb_ident);
 939                 if (!cps.clp) {
 940                         trace_nfs_cb_no_clp(rqstp->rq_xid, hdr_arg.cb_ident);
 941                         goto out_invalidcred;
 942                 }
 943                 if (!check_gss_callback_principal(cps.clp, rqstp)) {
 944                         trace_nfs_cb_badprinc(rqstp->rq_xid, hdr_arg.cb_ident);
 945                         nfs_put_client(cps.clp);
 946                         goto out_invalidcred;
 947                 }
 948         }
 949
 950         cps.minorversion = hdr_arg.minorversion;
 951         hdr_res.taglen = hdr_arg.taglen;
 952         hdr_res.tag = hdr_arg.tag;
 953         if (encode_compound_hdr_res(&rqstp->rq_res_stream, &hdr_res) != 0) {
 954                 if (cps.clp)
 955                         nfs_put_client(cps.clp);
 956                 return rpc_system_err;
 957         }
 958         while (status == 0 && nops != hdr_arg.nops) {
 959                 status = process_op(nops, rqstp, &cps);
 960                 nops++;
 961         }
 962
 963         /* Buffer overflow in decode_ops_hdr or encode_ops_hdr. Return
 964         * resource error in cb_compound status without returning op */
 965         if (unlikely(status == htonl(NFS4ERR_RESOURCE_HDR))) {
 966                 status = htonl(NFS4ERR_RESOURCE);
 967                 nops--;
 968         }
 969
 970         if (svc_is_backchannel(rqstp) && cps.clp) {
 971                 rqstp->bc_to_initval = cps.clp->cl_rpcclient->cl_timeout->to_initval;
 972                 rqstp->bc_to_retries = cps.clp->cl_rpcclient->cl_timeout->to_retries;
 973         }
 974
 975         *hdr_res.status = status;
 976         *hdr_res.nops = htonl(nops);
 977         nfs4_cb_free_slot(&cps);
 978         nfs_put_client(cps.clp);
 979         return rpc_success;
 980
 981 out_invalidcred:
 982         pr_warn_ratelimited("NFS: NFSv4 callback contains invalid cred\n");
 983         rqstp->rq_auth_stat = rpc_autherr_badcred;
 984         return rpc_success;
 985 }
 986
 987 static int
 988 nfs_callback_dispatch(struct svc_rqst *rqstp)
 989 {
 990         const struct svc_procedure *procp = rqstp->rq_procinfo;
 991
 992         *rqstp->rq_accept_statp = procp->pc_func(rqstp);
 993         return 1;
 994 }
 995
 996 /*
 997  * Define NFS4 callback COMPOUND ops.
 998  */
 999 static struct callback_op callback_ops[] = {
1000         [0] = {
1001                 .res_maxsize = CB_OP_HDR_RES_MAXSZ,
1002         },
1003         [OP_CB_GETATTR] = {
1004                 .process_op = nfs4_callback_getattr,
1005                 .decode_args = decode_getattr_args,
1006                 .encode_res = encode_getattr_res,
1007                 .res_maxsize = CB_OP_GETATTR_RES_MAXSZ,
1008         },
1009         [OP_CB_RECALL] = {
1010                 .process_op = nfs4_callback_recall,
1011                 .decode_args = decode_recall_args,
1012                 .res_maxsize = CB_OP_RECALL_RES_MAXSZ,
1013         },
1014 #if defined(CONFIG_NFS_V4_1)
1015         [OP_CB_LAYOUTRECALL] = {
1016                 .process_op = nfs4_callback_layoutrecall,
1017                 .decode_args = decode_layoutrecall_args,
1018                 .res_maxsize = CB_OP_LAYOUTRECALL_RES_MAXSZ,
1019         },
1020         [OP_CB_NOTIFY_DEVICEID] = {
1021                 .process_op = nfs4_callback_devicenotify,
1022                 .decode_args = decode_devicenotify_args,
1023                 .res_maxsize = CB_OP_DEVICENOTIFY_RES_MAXSZ,
1024         },
1025         [OP_CB_SEQUENCE] = {
1026                 .process_op = nfs4_callback_sequence,
1027                 .decode_args = decode_cb_sequence_args,
1028                 .encode_res = encode_cb_sequence_res,
1029                 .res_maxsize = CB_OP_SEQUENCE_RES_MAXSZ,
1030         },
1031         [OP_CB_RECALL_ANY] = {
1032                 .process_op = nfs4_callback_recallany,
1033                 .decode_args = decode_recallany_args,
1034                 .res_maxsize = CB_OP_RECALLANY_RES_MAXSZ,
1035         },
1036         [OP_CB_RECALL_SLOT] = {
1037                 .process_op = nfs4_callback_recallslot,
1038                 .decode_args = decode_recallslot_args,
1039                 .res_maxsize = CB_OP_RECALLSLOT_RES_MAXSZ,
1040         },
1041         [OP_CB_NOTIFY_LOCK] = {
1042                 .process_op = nfs4_callback_notify_lock,
1043                 .decode_args = decode_notify_lock_args,
1044                 .res_maxsize = CB_OP_NOTIFY_LOCK_RES_MAXSZ,
1045         },
1046 #endif /* CONFIG_NFS_V4_1 */
1047 #ifdef CONFIG_NFS_V4_2
1048         [OP_CB_OFFLOAD] = {
1049                 .process_op = nfs4_callback_offload,
1050                 .decode_args = decode_offload_args,
1051                 .res_maxsize = CB_OP_OFFLOAD_RES_MAXSZ,
1052         },
1053 #endif /* CONFIG_NFS_V4_2 */
1054 };
1055
1056 /*
1057  * Define NFS4 callback procedures
1058  */
1059 static const struct svc_procedure nfs4_callback_procedures1[] = {
1060         [CB_NULL] = {
1061                 .pc_func = nfs4_callback_null,
1062                 .pc_encode = nfs4_encode_void,
1063                 .pc_xdrressize = 1,
1064                 .pc_name = "NULL",
1065         },
1066         [CB_COMPOUND] = {
1067                 .pc_func = nfs4_callback_compound,
1068                 .pc_encode = nfs4_encode_void,
1069                 .pc_argsize = 256,
1070                 .pc_argzero = 256,
1071                 .pc_ressize = 256,
1072                 .pc_xdrressize = NFS4_CALLBACK_BUFSIZE,
1073                 .pc_name = "COMPOUND",
1074         }
1075 };
1076
1077 static DEFINE_PER_CPU_ALIGNED(unsigned long,
1078                               nfs4_callback_count1[ARRAY_SIZE(nfs4_callback_procedures1)]);
1079 const struct svc_version nfs4_callback_version1 = {
1080         .vs_vers = 1,
1081         .vs_nproc = ARRAY_SIZE(nfs4_callback_procedures1),
1082         .vs_proc = nfs4_callback_procedures1,
1083         .vs_count = nfs4_callback_count1,
1084         .vs_xdrsize = NFS4_CALLBACK_XDRSIZE,
1085         .vs_dispatch = nfs_callback_dispatch,
1086         .vs_hidden = true,
1087         .vs_need_cong_ctrl = true,
1088 };
1089
1090 static DEFINE_PER_CPU_ALIGNED(unsigned long,
1091                               nfs4_callback_count4[ARRAY_SIZE(nfs4_callback_procedures1)]);
1092 const struct svc_version nfs4_callback_version4 = {
1093         .vs_vers = 4,
1094         .vs_nproc = ARRAY_SIZE(nfs4_callback_procedures1),
1095         .vs_proc = nfs4_callback_procedures1,
1096         .vs_count = nfs4_callback_count4,
1097         .vs_xdrsize = NFS4_CALLBACK_XDRSIZE,
1098         .vs_dispatch = nfs_callback_dispatch,
1099         .vs_hidden = true,
1100         .vs_need_cong_ctrl = true,
1101 };