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
  22 #define CB_OP_TAGLEN_MAXSZ              (512)
  23 #define CB_OP_HDR_RES_MAXSZ             (2 * 4) // opcode, status
  24 #define CB_OP_GETATTR_BITMAP_MAXSZ      (4 * 4) // bitmap length, 3 bitmaps
  25 #define CB_OP_GETATTR_RES_MAXSZ         (CB_OP_HDR_RES_MAXSZ + \
  26                                          CB_OP_GETATTR_BITMAP_MAXSZ + \
  27                                          /* change, size, ctime, mtime */\
  28                                          (2 + 2 + 3 + 3) * 4)
  29 #define CB_OP_RECALL_RES_MAXSZ          (CB_OP_HDR_RES_MAXSZ)
  30
  31 #if defined(CONFIG_NFS_V4_1)
  32 #define CB_OP_LAYOUTRECALL_RES_MAXSZ    (CB_OP_HDR_RES_MAXSZ)
  33 #define CB_OP_DEVICENOTIFY_RES_MAXSZ    (CB_OP_HDR_RES_MAXSZ)
  34 #define CB_OP_SEQUENCE_RES_MAXSZ        (CB_OP_HDR_RES_MAXSZ + \
  35                                          NFS4_MAX_SESSIONID_LEN + \
  36                                          (1 + 3) * 4) // seqid, 3 slotids
  37 #define CB_OP_RECALLANY_RES_MAXSZ       (CB_OP_HDR_RES_MAXSZ)
  38 #define CB_OP_RECALLSLOT_RES_MAXSZ      (CB_OP_HDR_RES_MAXSZ)
  39 #define CB_OP_NOTIFY_LOCK_RES_MAXSZ     (CB_OP_HDR_RES_MAXSZ)
  40 #endif /* CONFIG_NFS_V4_1 */
  41 #ifdef CONFIG_NFS_V4_2
  42 #define CB_OP_OFFLOAD_RES_MAXSZ         (CB_OP_HDR_RES_MAXSZ)
  43 #endif /* CONFIG_NFS_V4_2 */
  44
  45 #define NFSDBG_FACILITY NFSDBG_CALLBACK
  46
  47 /* Internal error code */
  48 #define NFS4ERR_RESOURCE_HDR    11050
  49
  50 struct callback_op {
  51         __be32 (*process_op)(void *, void *, struct cb_process_state *);
  52         __be32 (*decode_args)(struct svc_rqst *, struct xdr_stream *, void *);
  53         __be32 (*encode_res)(struct svc_rqst *, struct xdr_stream *,
  54                         const void *);
  55         long res_maxsize;
  56 };
  57
  58 static struct callback_op callback_ops[];
  59
  60 static __be32 nfs4_callback_null(struct svc_rqst *rqstp)
  61 {
  62         return htonl(NFS4_OK);
  63 }
  64
  65 static int nfs4_decode_void(struct svc_rqst *rqstp, __be32 *p)
  66 {
  67         return xdr_argsize_check(rqstp, p);
  68 }
  69
  70 static int nfs4_encode_void(struct svc_rqst *rqstp, __be32 *p)
  71 {
  72         return xdr_ressize_check(rqstp, p);
  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         __be32 *p;
 262         __be32 status = 0;
 263         u32 tmp;
 264         int n, i;
 265         args->ndevs = 0;
 266
 267         /* Num of device notifications */
 268         p = xdr_inline_decode(xdr, sizeof(uint32_t));
 269         if (unlikely(p == NULL)) {
 270                 status = htonl(NFS4ERR_BADXDR);
 271                 goto out;
 272         }
 273         n = ntohl(*p++);
 274         if (n <= 0)
 275                 goto out;
 276         if (n > ULONG_MAX / sizeof(*args->devs)) {
 277                 status = htonl(NFS4ERR_BADXDR);
 278                 goto out;
 279         }
 280
 281         args->devs = kmalloc_array(n, sizeof(*args->devs), GFP_KERNEL);
 282         if (!args->devs) {
 283                 status = htonl(NFS4ERR_DELAY);
 284                 goto out;
 285         }
 286
 287         /* Decode each dev notification */
 288         for (i = 0; i < n; i++) {
 289                 struct cb_devicenotifyitem *dev = &args->devs[i];
 290
 291                 p = xdr_inline_decode(xdr, (4 * sizeof(uint32_t)) +
 292                                       NFS4_DEVICEID4_SIZE);
 293                 if (unlikely(p == NULL)) {
 294                         status = htonl(NFS4ERR_BADXDR);
 295                         goto err;
 296                 }
 297
 298                 tmp = ntohl(*p++);      /* bitmap size */
 299                 if (tmp != 1) {
 300                         status = htonl(NFS4ERR_INVAL);
 301                         goto err;
 302                 }
 303                 dev->cbd_notify_type = ntohl(*p++);
 304                 if (dev->cbd_notify_type != NOTIFY_DEVICEID4_CHANGE &&
 305                     dev->cbd_notify_type != NOTIFY_DEVICEID4_DELETE) {
 306                         status = htonl(NFS4ERR_INVAL);
 307                         goto err;
 308                 }
 309
 310                 tmp = ntohl(*p++);      /* opaque size */
 311                 if (((dev->cbd_notify_type == NOTIFY_DEVICEID4_CHANGE) &&
 312                      (tmp != NFS4_DEVICEID4_SIZE + 8)) ||
 313                     ((dev->cbd_notify_type == NOTIFY_DEVICEID4_DELETE) &&
 314                      (tmp != NFS4_DEVICEID4_SIZE + 4))) {
 315                         status = htonl(NFS4ERR_INVAL);
 316                         goto err;
 317                 }
 318                 dev->cbd_layout_type = ntohl(*p++);
 319                 memcpy(dev->cbd_dev_id.data, p, NFS4_DEVICEID4_SIZE);
 320                 p += XDR_QUADLEN(NFS4_DEVICEID4_SIZE);
 321
 322                 if (dev->cbd_layout_type == NOTIFY_DEVICEID4_CHANGE) {
 323                         p = xdr_inline_decode(xdr, sizeof(uint32_t));
 324                         if (unlikely(p == NULL)) {
 325                                 status = htonl(NFS4ERR_BADXDR);
 326                                 goto err;
 327                         }
 328                         dev->cbd_immediate = ntohl(*p++);
 329                 } else {
 330                         dev->cbd_immediate = 0;
 331                 }
 332
 333                 args->ndevs++;
 334
 335                 dprintk("%s: type %d layout 0x%x immediate %d\n",
 336                         __func__, dev->cbd_notify_type, dev->cbd_layout_type,
 337                         dev->cbd_immediate);
 338         }
 339 out:
 340         dprintk("%s: status %d ndevs %d\n",
 341                 __func__, ntohl(status), args->ndevs);
 342         return status;
 343 err:
 344         kfree(args->devs);
 345         goto out;
 346 }
 347
 348 static __be32 decode_sessionid(struct xdr_stream *xdr,
 349                                  struct nfs4_sessionid *sid)
 350 {
 351         __be32 *p;
 352
 353         p = xdr_inline_decode(xdr, NFS4_MAX_SESSIONID_LEN);
 354         if (unlikely(p == NULL))
 355                 return htonl(NFS4ERR_RESOURCE);
 356
 357         memcpy(sid->data, p, NFS4_MAX_SESSIONID_LEN);
 358         return 0;
 359 }
 360
 361 static __be32 decode_rc_list(struct xdr_stream *xdr,
 362                                struct referring_call_list *rc_list)
 363 {
 364         __be32 *p;
 365         int i;
 366         __be32 status;
 367
 368         status = decode_sessionid(xdr, &rc_list->rcl_sessionid);
 369         if (status)
 370                 goto out;
 371
 372         status = htonl(NFS4ERR_RESOURCE);
 373         p = xdr_inline_decode(xdr, sizeof(uint32_t));
 374         if (unlikely(p == NULL))
 375                 goto out;
 376
 377         rc_list->rcl_nrefcalls = ntohl(*p++);
 378         if (rc_list->rcl_nrefcalls) {
 379                 p = xdr_inline_decode(xdr,
 380                              rc_list->rcl_nrefcalls * 2 * sizeof(uint32_t));
 381                 if (unlikely(p == NULL))
 382                         goto out;
 383                 rc_list->rcl_refcalls = kmalloc_array(rc_list->rcl_nrefcalls,
 384                                                 sizeof(*rc_list->rcl_refcalls),
 385                                                 GFP_KERNEL);
 386                 if (unlikely(rc_list->rcl_refcalls == NULL))
 387                         goto out;
 388                 for (i = 0; i < rc_list->rcl_nrefcalls; i++) {
 389                         rc_list->rcl_refcalls[i].rc_sequenceid = ntohl(*p++);
 390                         rc_list->rcl_refcalls[i].rc_slotid = ntohl(*p++);
 391                 }
 392         }
 393         status = 0;
 394
 395 out:
 396         return status;
 397 }
 398
 399 static __be32 decode_cb_sequence_args(struct svc_rqst *rqstp,
 400                                         struct xdr_stream *xdr,
 401                                         void *argp)
 402 {
 403         struct cb_sequenceargs *args = argp;
 404         __be32 *p;
 405         int i;
 406         __be32 status;
 407
 408         status = decode_sessionid(xdr, &args->csa_sessionid);
 409         if (status)
 410                 return status;
 411
 412         p = xdr_inline_decode(xdr, 5 * sizeof(uint32_t));
 413         if (unlikely(p == NULL))
 414                 return htonl(NFS4ERR_RESOURCE);
 415
 416         args->csa_addr = svc_addr(rqstp);
 417         args->csa_sequenceid = ntohl(*p++);
 418         args->csa_slotid = ntohl(*p++);
 419         args->csa_highestslotid = ntohl(*p++);
 420         args->csa_cachethis = ntohl(*p++);
 421         args->csa_nrclists = ntohl(*p++);
 422         args->csa_rclists = NULL;
 423         if (args->csa_nrclists) {
 424                 args->csa_rclists = kmalloc_array(args->csa_nrclists,
 425                                                   sizeof(*args->csa_rclists),
 426                                                   GFP_KERNEL);
 427                 if (unlikely(args->csa_rclists == NULL))
 428                         return htonl(NFS4ERR_RESOURCE);
 429
 430                 for (i = 0; i < args->csa_nrclists; i++) {
 431                         status = decode_rc_list(xdr, &args->csa_rclists[i]);
 432                         if (status) {
 433                                 args->csa_nrclists = i;
 434                                 goto out_free;
 435                         }
 436                 }
 437         }
 438         return 0;
 439
 440 out_free:
 441         for (i = 0; i < args->csa_nrclists; i++)
 442                 kfree(args->csa_rclists[i].rcl_refcalls);
 443         kfree(args->csa_rclists);
 444         return status;
 445 }
 446
 447 static __be32 decode_recallany_args(struct svc_rqst *rqstp,
 448                                       struct xdr_stream *xdr,
 449                                       void *argp)
 450 {
 451         struct cb_recallanyargs *args = argp;
 452         uint32_t bitmap[2];
 453         __be32 *p, status;
 454
 455         p = xdr_inline_decode(xdr, 4);
 456         if (unlikely(p == NULL))
 457                 return htonl(NFS4ERR_BADXDR);
 458         args->craa_objs_to_keep = ntohl(*p++);
 459         status = decode_bitmap(xdr, bitmap);
 460         if (unlikely(status))
 461                 return status;
 462         args->craa_type_mask = bitmap[0];
 463
 464         return 0;
 465 }
 466
 467 static __be32 decode_recallslot_args(struct svc_rqst *rqstp,
 468                                         struct xdr_stream *xdr,
 469                                         void *argp)
 470 {
 471         struct cb_recallslotargs *args = argp;
 472         __be32 *p;
 473
 474         p = xdr_inline_decode(xdr, 4);
 475         if (unlikely(p == NULL))
 476                 return htonl(NFS4ERR_BADXDR);
 477         args->crsa_target_highest_slotid = ntohl(*p++);
 478         return 0;
 479 }
 480
 481 static __be32 decode_lockowner(struct xdr_stream *xdr, struct cb_notify_lock_args *args)
 482 {
 483         __be32          *p;
 484         unsigned int    len;
 485
 486         p = xdr_inline_decode(xdr, 12);
 487         if (unlikely(p == NULL))
 488                 return htonl(NFS4ERR_BADXDR);
 489
 490         p = xdr_decode_hyper(p, &args->cbnl_owner.clientid);
 491         len = be32_to_cpu(*p);
 492
 493         p = xdr_inline_decode(xdr, len);
 494         if (unlikely(p == NULL))
 495                 return htonl(NFS4ERR_BADXDR);
 496
 497         /* Only try to decode if the length is right */
 498         if (len == 20) {
 499                 p += 2; /* skip "lock id:" */
 500                 args->cbnl_owner.s_dev = be32_to_cpu(*p++);
 501                 xdr_decode_hyper(p, &args->cbnl_owner.id);
 502                 args->cbnl_valid = true;
 503         } else {
 504                 args->cbnl_owner.s_dev = 0;
 505                 args->cbnl_owner.id = 0;
 506                 args->cbnl_valid = false;
 507         }
 508         return 0;
 509 }
 510
 511 static __be32 decode_notify_lock_args(struct svc_rqst *rqstp,
 512                 struct xdr_stream *xdr, void *argp)
 513 {
 514         struct cb_notify_lock_args *args = argp;
 515         __be32 status;
 516
 517         status = decode_fh(xdr, &args->cbnl_fh);
 518         if (unlikely(status != 0))
 519                 return status;
 520         return decode_lockowner(xdr, args);
 521 }
 522
 523 #endif /* CONFIG_NFS_V4_1 */
 524 #ifdef CONFIG_NFS_V4_2
 525 static __be32 decode_write_response(struct xdr_stream *xdr,
 526                                         struct cb_offloadargs *args)
 527 {
 528         __be32 *p;
 529
 530         /* skip the always zero field */
 531         p = xdr_inline_decode(xdr, 4);
 532         if (unlikely(!p))
 533                 goto out;
 534         p++;
 535
 536         /* decode count, stable_how, verifier */
 537         p = xdr_inline_decode(xdr, 8 + 4);
 538         if (unlikely(!p))
 539                 goto out;
 540         p = xdr_decode_hyper(p, &args->wr_count);
 541         args->wr_writeverf.committed = be32_to_cpup(p);
 542         p = xdr_inline_decode(xdr, NFS4_VERIFIER_SIZE);
 543         if (likely(p)) {
 544                 memcpy(&args->wr_writeverf.verifier.data[0], p,
 545                         NFS4_VERIFIER_SIZE);
 546                 return 0;
 547         }
 548 out:
 549         return htonl(NFS4ERR_RESOURCE);
 550 }
 551
 552 static __be32 decode_offload_args(struct svc_rqst *rqstp,
 553                                         struct xdr_stream *xdr,
 554                                         void *data)
 555 {
 556         struct cb_offloadargs *args = data;
 557         __be32 *p;
 558         __be32 status;
 559
 560         /* decode fh */
 561         status = decode_fh(xdr, &args->coa_fh);
 562         if (unlikely(status != 0))
 563                 return status;
 564
 565         /* decode stateid */
 566         status = decode_stateid(xdr, &args->coa_stateid);
 567         if (unlikely(status != 0))
 568                 return status;
 569
 570         /* decode status */
 571         p = xdr_inline_decode(xdr, 4);
 572         if (unlikely(!p))
 573                 goto out;
 574         args->error = ntohl(*p++);
 575         if (!args->error) {
 576                 status = decode_write_response(xdr, args);
 577                 if (unlikely(status != 0))
 578                         return status;
 579         } else {
 580                 p = xdr_inline_decode(xdr, 8);
 581                 if (unlikely(!p))
 582                         goto out;
 583                 p = xdr_decode_hyper(p, &args->wr_count);
 584         }
 585         return 0;
 586 out:
 587         return htonl(NFS4ERR_RESOURCE);
 588 }
 589 #endif /* CONFIG_NFS_V4_2 */
 590 static __be32 encode_string(struct xdr_stream *xdr, unsigned int len, const char *str)
 591 {
 592         if (unlikely(xdr_stream_encode_opaque(xdr, str, len) < 0))
 593                 return cpu_to_be32(NFS4ERR_RESOURCE);
 594         return 0;
 595 }
 596
 597 static __be32 encode_attr_bitmap(struct xdr_stream *xdr, const uint32_t *bitmap, size_t sz)
 598 {
 599         if (xdr_stream_encode_uint32_array(xdr, bitmap, sz) < 0)
 600                 return cpu_to_be32(NFS4ERR_RESOURCE);
 601         return 0;
 602 }
 603
 604 static __be32 encode_attr_change(struct xdr_stream *xdr, const uint32_t *bitmap, uint64_t change)
 605 {
 606         __be32 *p;
 607
 608         if (!(bitmap[0] & FATTR4_WORD0_CHANGE))
 609                 return 0;
 610         p = xdr_reserve_space(xdr, 8);
 611         if (unlikely(!p))
 612                 return htonl(NFS4ERR_RESOURCE);
 613         p = xdr_encode_hyper(p, change);
 614         return 0;
 615 }
 616
 617 static __be32 encode_attr_size(struct xdr_stream *xdr, const uint32_t *bitmap, uint64_t size)
 618 {
 619         __be32 *p;
 620
 621         if (!(bitmap[0] & FATTR4_WORD0_SIZE))
 622                 return 0;
 623         p = xdr_reserve_space(xdr, 8);
 624         if (unlikely(!p))
 625                 return htonl(NFS4ERR_RESOURCE);
 626         p = xdr_encode_hyper(p, size);
 627         return 0;
 628 }
 629
 630 static __be32 encode_attr_time(struct xdr_stream *xdr, const struct timespec *time)
 631 {
 632         __be32 *p;
 633
 634         p = xdr_reserve_space(xdr, 12);
 635         if (unlikely(!p))
 636                 return htonl(NFS4ERR_RESOURCE);
 637         p = xdr_encode_hyper(p, time->tv_sec);
 638         *p = htonl(time->tv_nsec);
 639         return 0;
 640 }
 641
 642 static __be32 encode_attr_ctime(struct xdr_stream *xdr, const uint32_t *bitmap, const struct timespec *time)
 643 {
 644         if (!(bitmap[1] & FATTR4_WORD1_TIME_METADATA))
 645                 return 0;
 646         return encode_attr_time(xdr,time);
 647 }
 648
 649 static __be32 encode_attr_mtime(struct xdr_stream *xdr, const uint32_t *bitmap, const struct timespec *time)
 650 {
 651         if (!(bitmap[1] & FATTR4_WORD1_TIME_MODIFY))
 652                 return 0;
 653         return encode_attr_time(xdr,time);
 654 }
 655
 656 static __be32 encode_compound_hdr_res(struct xdr_stream *xdr, struct cb_compound_hdr_res *hdr)
 657 {
 658         __be32 status;
 659
 660         hdr->status = xdr_reserve_space(xdr, 4);
 661         if (unlikely(hdr->status == NULL))
 662                 return htonl(NFS4ERR_RESOURCE);
 663         status = encode_string(xdr, hdr->taglen, hdr->tag);
 664         if (unlikely(status != 0))
 665                 return status;
 666         hdr->nops = xdr_reserve_space(xdr, 4);
 667         if (unlikely(hdr->nops == NULL))
 668                 return htonl(NFS4ERR_RESOURCE);
 669         return 0;
 670 }
 671
 672 static __be32 encode_op_hdr(struct xdr_stream *xdr, uint32_t op, __be32 res)
 673 {
 674         __be32 *p;
 675
 676         p = xdr_reserve_space(xdr, 8);
 677         if (unlikely(p == NULL))
 678                 return htonl(NFS4ERR_RESOURCE_HDR);
 679         *p++ = htonl(op);
 680         *p = res;
 681         return 0;
 682 }
 683
 684 static __be32 encode_getattr_res(struct svc_rqst *rqstp, struct xdr_stream *xdr,
 685                 const void *resp)
 686 {
 687         const struct cb_getattrres *res = resp;
 688         __be32 *savep = NULL;
 689         __be32 status = res->status;
 690
 691         if (unlikely(status != 0))
 692                 goto out;
 693         status = encode_attr_bitmap(xdr, res->bitmap, ARRAY_SIZE(res->bitmap));
 694         if (unlikely(status != 0))
 695                 goto out;
 696         status = cpu_to_be32(NFS4ERR_RESOURCE);
 697         savep = xdr_reserve_space(xdr, sizeof(*savep));
 698         if (unlikely(!savep))
 699                 goto out;
 700         status = encode_attr_change(xdr, res->bitmap, res->change_attr);
 701         if (unlikely(status != 0))
 702                 goto out;
 703         status = encode_attr_size(xdr, res->bitmap, res->size);
 704         if (unlikely(status != 0))
 705                 goto out;
 706         status = encode_attr_ctime(xdr, res->bitmap, &res->ctime);
 707         if (unlikely(status != 0))
 708                 goto out;
 709         status = encode_attr_mtime(xdr, res->bitmap, &res->mtime);
 710         *savep = htonl((unsigned int)((char *)xdr->p - (char *)(savep+1)));
 711 out:
 712         return status;
 713 }
 714
 715 #if defined(CONFIG_NFS_V4_1)
 716
 717 static __be32 encode_sessionid(struct xdr_stream *xdr,
 718                                  const struct nfs4_sessionid *sid)
 719 {
 720         __be32 *p;
 721
 722         p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN);
 723         if (unlikely(p == NULL))
 724                 return htonl(NFS4ERR_RESOURCE);
 725
 726         memcpy(p, sid, NFS4_MAX_SESSIONID_LEN);
 727         return 0;
 728 }
 729
 730 static __be32 encode_cb_sequence_res(struct svc_rqst *rqstp,
 731                                        struct xdr_stream *xdr,
 732                                        const void *resp)
 733 {
 734         const struct cb_sequenceres *res = resp;
 735         __be32 *p;
 736         __be32 status = res->csr_status;
 737
 738         if (unlikely(status != 0))
 739                 return status;
 740
 741         status = encode_sessionid(xdr, &res->csr_sessionid);
 742         if (status)
 743                 return status;
 744
 745         p = xdr_reserve_space(xdr, 4 * sizeof(uint32_t));
 746         if (unlikely(p == NULL))
 747                 return htonl(NFS4ERR_RESOURCE);
 748
 749         *p++ = htonl(res->csr_sequenceid);
 750         *p++ = htonl(res->csr_slotid);
 751         *p++ = htonl(res->csr_highestslotid);
 752         *p++ = htonl(res->csr_target_highestslotid);
 753         return 0;
 754 }
 755
 756 static __be32
 757 preprocess_nfs41_op(int nop, unsigned int op_nr, struct callback_op **op)
 758 {
 759         if (op_nr == OP_CB_SEQUENCE) {
 760                 if (nop != 0)
 761                         return htonl(NFS4ERR_SEQUENCE_POS);
 762         } else {
 763                 if (nop == 0)
 764                         return htonl(NFS4ERR_OP_NOT_IN_SESSION);
 765         }
 766
 767         switch (op_nr) {
 768         case OP_CB_GETATTR:
 769         case OP_CB_RECALL:
 770         case OP_CB_SEQUENCE:
 771         case OP_CB_RECALL_ANY:
 772         case OP_CB_RECALL_SLOT:
 773         case OP_CB_LAYOUTRECALL:
 774         case OP_CB_NOTIFY_DEVICEID:
 775         case OP_CB_NOTIFY_LOCK:
 776                 *op = &callback_ops[op_nr];
 777                 break;
 778
 779         case OP_CB_NOTIFY:
 780         case OP_CB_PUSH_DELEG:
 781         case OP_CB_RECALLABLE_OBJ_AVAIL:
 782         case OP_CB_WANTS_CANCELLED:
 783                 return htonl(NFS4ERR_NOTSUPP);
 784
 785         default:
 786                 return htonl(NFS4ERR_OP_ILLEGAL);
 787         }
 788
 789         return htonl(NFS_OK);
 790 }
 791
 792 static void nfs4_callback_free_slot(struct nfs4_session *session,
 793                 struct nfs4_slot *slot)
 794 {
 795         struct nfs4_slot_table *tbl = &session->bc_slot_table;
 796
 797         spin_lock(&tbl->slot_tbl_lock);
 798         /*
 799          * Let the state manager know callback processing done.
 800          * A single slot, so highest used slotid is either 0 or -1
 801          */
 802         nfs4_free_slot(tbl, slot);
 803         spin_unlock(&tbl->slot_tbl_lock);
 804 }
 805
 806 static void nfs4_cb_free_slot(struct cb_process_state *cps)
 807 {
 808         if (cps->slot) {
 809                 nfs4_callback_free_slot(cps->clp->cl_session, cps->slot);
 810                 cps->slot = NULL;
 811         }
 812 }
 813
 814 #else /* CONFIG_NFS_V4_1 */
 815
 816 static __be32
 817 preprocess_nfs41_op(int nop, unsigned int op_nr, struct callback_op **op)
 818 {
 819         return htonl(NFS4ERR_MINOR_VERS_MISMATCH);
 820 }
 821
 822 static void nfs4_cb_free_slot(struct cb_process_state *cps)
 823 {
 824 }
 825 #endif /* CONFIG_NFS_V4_1 */
 826
 827 #ifdef CONFIG_NFS_V4_2
 828 static __be32
 829 preprocess_nfs42_op(int nop, unsigned int op_nr, struct callback_op **op)
 830 {
 831         __be32 status = preprocess_nfs41_op(nop, op_nr, op);
 832         if (status != htonl(NFS4ERR_OP_ILLEGAL))
 833                 return status;
 834
 835         if (op_nr == OP_CB_OFFLOAD) {
 836                 *op = &callback_ops[op_nr];
 837                 return htonl(NFS_OK);
 838         } else
 839                 return htonl(NFS4ERR_NOTSUPP);
 840         return htonl(NFS4ERR_OP_ILLEGAL);
 841 }
 842 #else /* CONFIG_NFS_V4_2 */
 843 static __be32
 844 preprocess_nfs42_op(int nop, unsigned int op_nr, struct callback_op **op)
 845 {
 846         return htonl(NFS4ERR_MINOR_VERS_MISMATCH);
 847 }
 848 #endif /* CONFIG_NFS_V4_2 */
 849
 850 static __be32
 851 preprocess_nfs4_op(unsigned int op_nr, struct callback_op **op)
 852 {
 853         switch (op_nr) {
 854         case OP_CB_GETATTR:
 855         case OP_CB_RECALL:
 856                 *op = &callback_ops[op_nr];
 857                 break;
 858         default:
 859                 return htonl(NFS4ERR_OP_ILLEGAL);
 860         }
 861
 862         return htonl(NFS_OK);
 863 }
 864
 865 static __be32 process_op(int nop, struct svc_rqst *rqstp,
 866                 struct xdr_stream *xdr_in, void *argp,
 867                 struct xdr_stream *xdr_out, void *resp,
 868                 struct cb_process_state *cps)
 869 {
 870         struct callback_op *op = &callback_ops[0];
 871         unsigned int op_nr;
 872         __be32 status;
 873         long maxlen;
 874         __be32 res;
 875
 876         status = decode_op_hdr(xdr_in, &op_nr);
 877         if (unlikely(status))
 878                 return status;
 879
 880         switch (cps->minorversion) {
 881         case 0:
 882                 status = preprocess_nfs4_op(op_nr, &op);
 883                 break;
 884         case 1:
 885                 status = preprocess_nfs41_op(nop, op_nr, &op);
 886                 break;
 887         case 2:
 888                 status = preprocess_nfs42_op(nop, op_nr, &op);
 889                 break;
 890         default:
 891                 status = htonl(NFS4ERR_MINOR_VERS_MISMATCH);
 892         }
 893
 894         if (status == htonl(NFS4ERR_OP_ILLEGAL))
 895                 op_nr = OP_CB_ILLEGAL;
 896         if (status)
 897                 goto encode_hdr;
 898
 899         if (cps->drc_status) {
 900                 status = cps->drc_status;
 901                 goto encode_hdr;
 902         }
 903
 904         maxlen = xdr_out->end - xdr_out->p;
 905         if (maxlen > 0 && maxlen < PAGE_SIZE) {
 906                 status = op->decode_args(rqstp, xdr_in, argp);
 907                 if (likely(status == 0))
 908                         status = op->process_op(argp, resp, cps);
 909         } else
 910                 status = htonl(NFS4ERR_RESOURCE);
 911
 912 encode_hdr:
 913         res = encode_op_hdr(xdr_out, op_nr, status);
 914         if (unlikely(res))
 915                 return res;
 916         if (op->encode_res != NULL && status == 0)
 917                 status = op->encode_res(rqstp, xdr_out, resp);
 918         return status;
 919 }
 920
 921 /*
 922  * Decode, process and encode a COMPOUND
 923  */
 924 static __be32 nfs4_callback_compound(struct svc_rqst *rqstp)
 925 {
 926         struct cb_compound_hdr_arg hdr_arg = { 0 };
 927         struct cb_compound_hdr_res hdr_res = { NULL };
 928         struct xdr_stream xdr_in, xdr_out;
 929         __be32 *p, status;
 930         struct cb_process_state cps = {
 931                 .drc_status = 0,
 932                 .clp = NULL,
 933                 .net = SVC_NET(rqstp),
 934         };
 935         unsigned int nops = 0;
 936
 937         xdr_init_decode(&xdr_in, &rqstp->rq_arg,
 938                         rqstp->rq_arg.head[0].iov_base, NULL);
 939
 940         p = (__be32*)((char *)rqstp->rq_res.head[0].iov_base + rqstp->rq_res.head[0].iov_len);
 941         xdr_init_encode(&xdr_out, &rqstp->rq_res, p, NULL);
 942
 943         status = decode_compound_hdr_arg(&xdr_in, &hdr_arg);
 944         if (status == htonl(NFS4ERR_RESOURCE))
 945                 return rpc_garbage_args;
 946
 947         if (hdr_arg.minorversion == 0) {
 948                 cps.clp = nfs4_find_client_ident(SVC_NET(rqstp), hdr_arg.cb_ident);
 949                 if (!cps.clp || !check_gss_callback_principal(cps.clp, rqstp)) {
 950                         if (cps.clp)
 951                                 nfs_put_client(cps.clp);
 952                         goto out_invalidcred;
 953                 }
 954         }
 955
 956         cps.minorversion = hdr_arg.minorversion;
 957         hdr_res.taglen = hdr_arg.taglen;
 958         hdr_res.tag = hdr_arg.tag;
 959         if (encode_compound_hdr_res(&xdr_out, &hdr_res) != 0) {
 960                 if (cps.clp)
 961                         nfs_put_client(cps.clp);
 962                 return rpc_system_err;
 963         }
 964         while (status == 0 && nops != hdr_arg.nops) {
 965                 status = process_op(nops, rqstp, &xdr_in,
 966                                     rqstp->rq_argp, &xdr_out, rqstp->rq_resp,
 967                                     &cps);
 968                 nops++;
 969         }
 970
 971         /* Buffer overflow in decode_ops_hdr or encode_ops_hdr. Return
 972         * resource error in cb_compound status without returning op */
 973         if (unlikely(status == htonl(NFS4ERR_RESOURCE_HDR))) {
 974                 status = htonl(NFS4ERR_RESOURCE);
 975                 nops--;
 976         }
 977
 978         *hdr_res.status = status;
 979         *hdr_res.nops = htonl(nops);
 980         nfs4_cb_free_slot(&cps);
 981         nfs_put_client(cps.clp);
 982         return rpc_success;
 983
 984 out_invalidcred:
 985         pr_warn_ratelimited("NFS: NFSv4 callback contains invalid cred\n");
 986         return svc_return_autherr(rqstp, rpc_autherr_badcred);
 987 }
 988
 989 /*
 990  * Define NFS4 callback COMPOUND ops.
 991  */
 992 static struct callback_op callback_ops[] = {
 993         [0] = {
 994                 .res_maxsize = CB_OP_HDR_RES_MAXSZ,
 995         },
 996         [OP_CB_GETATTR] = {
 997                 .process_op = nfs4_callback_getattr,
 998                 .decode_args = decode_getattr_args,
 999                 .encode_res = encode_getattr_res,
1000                 .res_maxsize = CB_OP_GETATTR_RES_MAXSZ,
1001         },
1002         [OP_CB_RECALL] = {
1003                 .process_op = nfs4_callback_recall,
1004                 .decode_args = decode_recall_args,
1005                 .res_maxsize = CB_OP_RECALL_RES_MAXSZ,
1006         },
1007 #if defined(CONFIG_NFS_V4_1)
1008         [OP_CB_LAYOUTRECALL] = {
1009                 .process_op = nfs4_callback_layoutrecall,
1010                 .decode_args = decode_layoutrecall_args,
1011                 .res_maxsize = CB_OP_LAYOUTRECALL_RES_MAXSZ,
1012         },
1013         [OP_CB_NOTIFY_DEVICEID] = {
1014                 .process_op = nfs4_callback_devicenotify,
1015                 .decode_args = decode_devicenotify_args,
1016                 .res_maxsize = CB_OP_DEVICENOTIFY_RES_MAXSZ,
1017         },
1018         [OP_CB_SEQUENCE] = {
1019                 .process_op = nfs4_callback_sequence,
1020                 .decode_args = decode_cb_sequence_args,
1021                 .encode_res = encode_cb_sequence_res,
1022                 .res_maxsize = CB_OP_SEQUENCE_RES_MAXSZ,
1023         },
1024         [OP_CB_RECALL_ANY] = {
1025                 .process_op = nfs4_callback_recallany,
1026                 .decode_args = decode_recallany_args,
1027                 .res_maxsize = CB_OP_RECALLANY_RES_MAXSZ,
1028         },
1029         [OP_CB_RECALL_SLOT] = {
1030                 .process_op = nfs4_callback_recallslot,
1031                 .decode_args = decode_recallslot_args,
1032                 .res_maxsize = CB_OP_RECALLSLOT_RES_MAXSZ,
1033         },
1034         [OP_CB_NOTIFY_LOCK] = {
1035                 .process_op = nfs4_callback_notify_lock,
1036                 .decode_args = decode_notify_lock_args,
1037                 .res_maxsize = CB_OP_NOTIFY_LOCK_RES_MAXSZ,
1038         },
1039 #endif /* CONFIG_NFS_V4_1 */
1040 #ifdef CONFIG_NFS_V4_2
1041         [OP_CB_OFFLOAD] = {
1042                 .process_op = nfs4_callback_offload,
1043                 .decode_args = decode_offload_args,
1044                 .res_maxsize = CB_OP_OFFLOAD_RES_MAXSZ,
1045         },
1046 #endif /* CONFIG_NFS_V4_2 */
1047 };
1048
1049 /*
1050  * Define NFS4 callback procedures
1051  */
1052 static const struct svc_procedure nfs4_callback_procedures1[] = {
1053         [CB_NULL] = {
1054                 .pc_func = nfs4_callback_null,
1055                 .pc_decode = nfs4_decode_void,
1056                 .pc_encode = nfs4_encode_void,
1057                 .pc_xdrressize = 1,
1058         },
1059         [CB_COMPOUND] = {
1060                 .pc_func = nfs4_callback_compound,
1061                 .pc_encode = nfs4_encode_void,
1062                 .pc_argsize = 256,
1063                 .pc_ressize = 256,
1064                 .pc_xdrressize = NFS4_CALLBACK_BUFSIZE,
1065         }
1066 };
1067
1068 static unsigned int nfs4_callback_count1[ARRAY_SIZE(nfs4_callback_procedures1)];
1069 const struct svc_version nfs4_callback_version1 = {
1070         .vs_vers = 1,
1071         .vs_nproc = ARRAY_SIZE(nfs4_callback_procedures1),
1072         .vs_proc = nfs4_callback_procedures1,
1073         .vs_count = nfs4_callback_count1,
1074         .vs_xdrsize = NFS4_CALLBACK_XDRSIZE,
1075         .vs_dispatch = NULL,
1076         .vs_hidden = true,
1077         .vs_need_cong_ctrl = true,
1078 };
1079
1080 static unsigned int nfs4_callback_count4[ARRAY_SIZE(nfs4_callback_procedures1)];
1081 const struct svc_version nfs4_callback_version4 = {
1082         .vs_vers = 4,
1083         .vs_nproc = ARRAY_SIZE(nfs4_callback_procedures1),
1084         .vs_proc = nfs4_callback_procedures1,
1085         .vs_count = nfs4_callback_count4,
1086         .vs_xdrsize = NFS4_CALLBACK_XDRSIZE,
1087         .vs_dispatch = NULL,
1088         .vs_hidden = true,
1089         .vs_need_cong_ctrl = true,
1090 };