fs/nfs/callback_xdr.c

   1 /*
   2  * linux/fs/nfs/callback_xdr.c
   3  *
   4  * Copyright (C) 2004 Trond Myklebust
   5  *
   6  * NFSv4 callback encode/decode procedures
   7  */
   8 #include <linux/kernel.h>
   9 #include <linux/sunrpc/svc.h>
  10 #include <linux/nfs4.h>
  11 #include <linux/nfs_fs.h>
  12 #include <linux/ratelimit.h>
  13 #include <linux/printk.h>
  14 #include <linux/slab.h>
  15 #include <linux/sunrpc/bc_xprt.h>
  16 #include "nfs4_fs.h"
  17 #include "callback.h"
  18 #include "internal.h"
  19 #include "nfs4session.h"
  20
  21 #define CB_OP_TAGLEN_MAXSZ              (512)
  22 #define CB_OP_HDR_RES_MAXSZ             (2 * 4) // opcode, status
  23 #define CB_OP_GETATTR_BITMAP_MAXSZ      (4 * 4) // bitmap length, 3 bitmaps
  24 #define CB_OP_GETATTR_RES_MAXSZ         (CB_OP_HDR_RES_MAXSZ + \
  25                                          CB_OP_GETATTR_BITMAP_MAXSZ + \
  26                                          /* change, size, ctime, mtime */\
  27                                          (2 + 2 + 3 + 3) * 4)
  28 #define CB_OP_RECALL_RES_MAXSZ          (CB_OP_HDR_RES_MAXSZ)
  29
  30 #if defined(CONFIG_NFS_V4_1)
  31 #define CB_OP_LAYOUTRECALL_RES_MAXSZ    (CB_OP_HDR_RES_MAXSZ)
  32 #define CB_OP_DEVICENOTIFY_RES_MAXSZ    (CB_OP_HDR_RES_MAXSZ)
  33 #define CB_OP_SEQUENCE_RES_MAXSZ        (CB_OP_HDR_RES_MAXSZ + \
  34                                          NFS4_MAX_SESSIONID_LEN + \
  35                                          (1 + 3) * 4) // seqid, 3 slotids
  36 #define CB_OP_RECALLANY_RES_MAXSZ       (CB_OP_HDR_RES_MAXSZ)
  37 #define CB_OP_RECALLSLOT_RES_MAXSZ      (CB_OP_HDR_RES_MAXSZ)
  38 #define CB_OP_NOTIFY_LOCK_RES_MAXSZ     (CB_OP_HDR_RES_MAXSZ)
  39 #endif /* CONFIG_NFS_V4_1 */
  40
  41 #define NFSDBG_FACILITY NFSDBG_CALLBACK
  42
  43 /* Internal error code */
  44 #define NFS4ERR_RESOURCE_HDR    11050
  45
  46 typedef __be32 (*callback_process_op_t)(void *, void *,
  47                                         struct cb_process_state *);
  48 typedef __be32 (*callback_decode_arg_t)(struct svc_rqst *, struct xdr_stream *, void *);
  49 typedef __be32 (*callback_encode_res_t)(struct svc_rqst *, struct xdr_stream *, void *);
  50
  51
  52 struct callback_op {
  53         callback_process_op_t process_op;
  54         callback_decode_arg_t decode_args;
  55         callback_encode_res_t encode_res;
  56         long res_maxsize;
  57 };
  58
  59 static struct callback_op callback_ops[];
  60
  61 static __be32 nfs4_callback_null(struct svc_rqst *rqstp, void *argp, void *resp)
  62 {
  63         return htonl(NFS4_OK);
  64 }
  65
  66 static int nfs4_decode_void(struct svc_rqst *rqstp, __be32 *p, void *dummy)
  67 {
  68         return xdr_argsize_check(rqstp, p);
  69 }
  70
  71 static int nfs4_encode_void(struct svc_rqst *rqstp, __be32 *p, void *dummy)
  72 {
  73         return xdr_ressize_check(rqstp, p);
  74 }
  75
  76 static __be32 *read_buf(struct xdr_stream *xdr, size_t nbytes)
  77 {
  78         __be32 *p;
  79
  80         p = xdr_inline_decode(xdr, nbytes);
  81         if (unlikely(p == NULL))
  82                 printk(KERN_WARNING "NFS: NFSv4 callback reply buffer overflowed!\n");
  83         return p;
  84 }
  85
  86 static __be32 decode_string(struct xdr_stream *xdr, unsigned int *len,
  87                 const char **str, size_t maxlen)
  88 {
  89         ssize_t err;
  90
  91         err = xdr_stream_decode_opaque_inline(xdr, (void **)str, maxlen);
  92         if (err < 0)
  93                 return cpu_to_be32(NFS4ERR_RESOURCE);
  94         *len = err;
  95         return 0;
  96 }
  97
  98 static __be32 decode_fh(struct xdr_stream *xdr, struct nfs_fh *fh)
  99 {
 100         __be32 *p;
 101
 102         p = read_buf(xdr, 4);
 103         if (unlikely(p == NULL))
 104                 return htonl(NFS4ERR_RESOURCE);
 105         fh->size = ntohl(*p);
 106         if (fh->size > NFS4_FHSIZE)
 107                 return htonl(NFS4ERR_BADHANDLE);
 108         p = read_buf(xdr, fh->size);
 109         if (unlikely(p == NULL))
 110                 return htonl(NFS4ERR_RESOURCE);
 111         memcpy(&fh->data[0], p, fh->size);
 112         memset(&fh->data[fh->size], 0, sizeof(fh->data) - fh->size);
 113         return 0;
 114 }
 115
 116 static __be32 decode_bitmap(struct xdr_stream *xdr, uint32_t *bitmap)
 117 {
 118         __be32 *p;
 119         unsigned int attrlen;
 120
 121         p = read_buf(xdr, 4);
 122         if (unlikely(p == NULL))
 123                 return htonl(NFS4ERR_RESOURCE);
 124         attrlen = ntohl(*p);
 125         p = read_buf(xdr, attrlen << 2);
 126         if (unlikely(p == NULL))
 127                 return htonl(NFS4ERR_RESOURCE);
 128         if (likely(attrlen > 0))
 129                 bitmap[0] = ntohl(*p++);
 130         if (attrlen > 1)
 131                 bitmap[1] = ntohl(*p);
 132         return 0;
 133 }
 134
 135 static __be32 decode_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
 136 {
 137         __be32 *p;
 138
 139         p = read_buf(xdr, NFS4_STATEID_SIZE);
 140         if (unlikely(p == NULL))
 141                 return htonl(NFS4ERR_RESOURCE);
 142         memcpy(stateid->data, p, NFS4_STATEID_SIZE);
 143         return 0;
 144 }
 145
 146 static __be32 decode_delegation_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
 147 {
 148         stateid->type = NFS4_DELEGATION_STATEID_TYPE;
 149         return decode_stateid(xdr, stateid);
 150 }
 151
 152 static __be32 decode_compound_hdr_arg(struct xdr_stream *xdr, struct cb_compound_hdr_arg *hdr)
 153 {
 154         __be32 *p;
 155         __be32 status;
 156
 157         status = decode_string(xdr, &hdr->taglen, &hdr->tag, CB_OP_TAGLEN_MAXSZ);
 158         if (unlikely(status != 0))
 159                 return status;
 160         p = read_buf(xdr, 12);
 161         if (unlikely(p == NULL))
 162                 return htonl(NFS4ERR_RESOURCE);
 163         hdr->minorversion = ntohl(*p++);
 164         /* Check for minor version support */
 165         if (hdr->minorversion <= NFS4_MAX_MINOR_VERSION) {
 166                 hdr->cb_ident = ntohl(*p++); /* ignored by v4.1 and v4.2 */
 167         } else {
 168                 pr_warn_ratelimited("NFS: %s: NFSv4 server callback with "
 169                         "illegal minor version %u!\n",
 170                         __func__, hdr->minorversion);
 171                 return htonl(NFS4ERR_MINOR_VERS_MISMATCH);
 172         }
 173         hdr->nops = ntohl(*p);
 174         return 0;
 175 }
 176
 177 static __be32 decode_op_hdr(struct xdr_stream *xdr, unsigned int *op)
 178 {
 179         __be32 *p;
 180         p = read_buf(xdr, 4);
 181         if (unlikely(p == NULL))
 182                 return htonl(NFS4ERR_RESOURCE_HDR);
 183         *op = ntohl(*p);
 184         return 0;
 185 }
 186
 187 static __be32 decode_getattr_args(struct svc_rqst *rqstp, struct xdr_stream *xdr, struct cb_getattrargs *args)
 188 {
 189         __be32 status;
 190
 191         status = decode_fh(xdr, &args->fh);
 192         if (unlikely(status != 0))
 193                 return status;
 194         return decode_bitmap(xdr, args->bitmap);
 195 }
 196
 197 static __be32 decode_recall_args(struct svc_rqst *rqstp, struct xdr_stream *xdr, struct cb_recallargs *args)
 198 {
 199         __be32 *p;
 200         __be32 status;
 201
 202         status = decode_delegation_stateid(xdr, &args->stateid);
 203         if (unlikely(status != 0))
 204                 return status;
 205         p = read_buf(xdr, 4);
 206         if (unlikely(p == NULL))
 207                 return htonl(NFS4ERR_RESOURCE);
 208         args->truncate = ntohl(*p);
 209         return decode_fh(xdr, &args->fh);
 210 }
 211
 212 #if defined(CONFIG_NFS_V4_1)
 213 static __be32 decode_layout_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
 214 {
 215         stateid->type = NFS4_LAYOUT_STATEID_TYPE;
 216         return decode_stateid(xdr, stateid);
 217 }
 218
 219 static __be32 decode_layoutrecall_args(struct svc_rqst *rqstp,
 220                                        struct xdr_stream *xdr,
 221                                        struct cb_layoutrecallargs *args)
 222 {
 223         __be32 *p;
 224         __be32 status = 0;
 225         uint32_t iomode;
 226
 227         p = read_buf(xdr, 4 * sizeof(uint32_t));
 228         if (unlikely(p == NULL))
 229                 return htonl(NFS4ERR_BADXDR);
 230
 231         args->cbl_layout_type = ntohl(*p++);
 232         /* Depite the spec's xdr, iomode really belongs in the FILE switch,
 233          * as it is unusable and ignored with the other types.
 234          */
 235         iomode = ntohl(*p++);
 236         args->cbl_layoutchanged = ntohl(*p++);
 237         args->cbl_recall_type = ntohl(*p++);
 238
 239         if (args->cbl_recall_type == RETURN_FILE) {
 240                 args->cbl_range.iomode = iomode;
 241                 status = decode_fh(xdr, &args->cbl_fh);
 242                 if (unlikely(status != 0))
 243                         return status;
 244
 245                 p = read_buf(xdr, 2 * sizeof(uint64_t));
 246                 if (unlikely(p == NULL))
 247                         return htonl(NFS4ERR_BADXDR);
 248                 p = xdr_decode_hyper(p, &args->cbl_range.offset);
 249                 p = xdr_decode_hyper(p, &args->cbl_range.length);
 250                 return decode_layout_stateid(xdr, &args->cbl_stateid);
 251         } else if (args->cbl_recall_type == RETURN_FSID) {
 252                 p = read_buf(xdr, 2 * sizeof(uint64_t));
 253                 if (unlikely(p == NULL))
 254                         return htonl(NFS4ERR_BADXDR);
 255                 p = xdr_decode_hyper(p, &args->cbl_fsid.major);
 256                 p = xdr_decode_hyper(p, &args->cbl_fsid.minor);
 257         } else if (args->cbl_recall_type != RETURN_ALL)
 258                 return htonl(NFS4ERR_BADXDR);
 259         return 0;
 260 }
 261
 262 static
 263 __be32 decode_devicenotify_args(struct svc_rqst *rqstp,
 264                                 struct xdr_stream *xdr,
 265                                 struct cb_devicenotifyargs *args)
 266 {
 267         __be32 *p;
 268         __be32 status = 0;
 269         u32 tmp;
 270         int n, i;
 271         args->ndevs = 0;
 272
 273         /* Num of device notifications */
 274         p = read_buf(xdr, sizeof(uint32_t));
 275         if (unlikely(p == NULL)) {
 276                 status = htonl(NFS4ERR_BADXDR);
 277                 goto out;
 278         }
 279         n = ntohl(*p++);
 280         if (n <= 0)
 281                 goto out;
 282         if (n > ULONG_MAX / sizeof(*args->devs)) {
 283                 status = htonl(NFS4ERR_BADXDR);
 284                 goto out;
 285         }
 286
 287         args->devs = kmalloc_array(n, sizeof(*args->devs), GFP_KERNEL);
 288         if (!args->devs) {
 289                 status = htonl(NFS4ERR_DELAY);
 290                 goto out;
 291         }
 292
 293         /* Decode each dev notification */
 294         for (i = 0; i < n; i++) {
 295                 struct cb_devicenotifyitem *dev = &args->devs[i];
 296
 297                 p = read_buf(xdr, (4 * sizeof(uint32_t)) + NFS4_DEVICEID4_SIZE);
 298                 if (unlikely(p == NULL)) {
 299                         status = htonl(NFS4ERR_BADXDR);
 300                         goto err;
 301                 }
 302
 303                 tmp = ntohl(*p++);      /* bitmap size */
 304                 if (tmp != 1) {
 305                         status = htonl(NFS4ERR_INVAL);
 306                         goto err;
 307                 }
 308                 dev->cbd_notify_type = ntohl(*p++);
 309                 if (dev->cbd_notify_type != NOTIFY_DEVICEID4_CHANGE &&
 310                     dev->cbd_notify_type != NOTIFY_DEVICEID4_DELETE) {
 311                         status = htonl(NFS4ERR_INVAL);
 312                         goto err;
 313                 }
 314
 315                 tmp = ntohl(*p++);      /* opaque size */
 316                 if (((dev->cbd_notify_type == NOTIFY_DEVICEID4_CHANGE) &&
 317                      (tmp != NFS4_DEVICEID4_SIZE + 8)) ||
 318                     ((dev->cbd_notify_type == NOTIFY_DEVICEID4_DELETE) &&
 319                      (tmp != NFS4_DEVICEID4_SIZE + 4))) {
 320                         status = htonl(NFS4ERR_INVAL);
 321                         goto err;
 322                 }
 323                 dev->cbd_layout_type = ntohl(*p++);
 324                 memcpy(dev->cbd_dev_id.data, p, NFS4_DEVICEID4_SIZE);
 325                 p += XDR_QUADLEN(NFS4_DEVICEID4_SIZE);
 326
 327                 if (dev->cbd_layout_type == NOTIFY_DEVICEID4_CHANGE) {
 328                         p = read_buf(xdr, sizeof(uint32_t));
 329                         if (unlikely(p == NULL)) {
 330                                 status = htonl(NFS4ERR_BADXDR);
 331                                 goto err;
 332                         }
 333                         dev->cbd_immediate = ntohl(*p++);
 334                 } else {
 335                         dev->cbd_immediate = 0;
 336                 }
 337
 338                 args->ndevs++;
 339
 340                 dprintk("%s: type %d layout 0x%x immediate %d\n",
 341                         __func__, dev->cbd_notify_type, dev->cbd_layout_type,
 342                         dev->cbd_immediate);
 343         }
 344 out:
 345         dprintk("%s: status %d ndevs %d\n",
 346                 __func__, ntohl(status), args->ndevs);
 347         return status;
 348 err:
 349         kfree(args->devs);
 350         goto out;
 351 }
 352
 353 static __be32 decode_sessionid(struct xdr_stream *xdr,
 354                                  struct nfs4_sessionid *sid)
 355 {
 356         __be32 *p;
 357
 358         p = read_buf(xdr, NFS4_MAX_SESSIONID_LEN);
 359         if (unlikely(p == NULL))
 360                 return htonl(NFS4ERR_RESOURCE);
 361
 362         memcpy(sid->data, p, NFS4_MAX_SESSIONID_LEN);
 363         return 0;
 364 }
 365
 366 static __be32 decode_rc_list(struct xdr_stream *xdr,
 367                                struct referring_call_list *rc_list)
 368 {
 369         __be32 *p;
 370         int i;
 371         __be32 status;
 372
 373         status = decode_sessionid(xdr, &rc_list->rcl_sessionid);
 374         if (status)
 375                 goto out;
 376
 377         status = htonl(NFS4ERR_RESOURCE);
 378         p = read_buf(xdr, sizeof(uint32_t));
 379         if (unlikely(p == NULL))
 380                 goto out;
 381
 382         rc_list->rcl_nrefcalls = ntohl(*p++);
 383         if (rc_list->rcl_nrefcalls) {
 384                 p = read_buf(xdr,
 385                              rc_list->rcl_nrefcalls * 2 * sizeof(uint32_t));
 386                 if (unlikely(p == NULL))
 387                         goto out;
 388                 rc_list->rcl_refcalls = kmalloc_array(rc_list->rcl_nrefcalls,
 389                                                 sizeof(*rc_list->rcl_refcalls),
 390                                                 GFP_KERNEL);
 391                 if (unlikely(rc_list->rcl_refcalls == NULL))
 392                         goto out;
 393                 for (i = 0; i < rc_list->rcl_nrefcalls; i++) {
 394                         rc_list->rcl_refcalls[i].rc_sequenceid = ntohl(*p++);
 395                         rc_list->rcl_refcalls[i].rc_slotid = ntohl(*p++);
 396                 }
 397         }
 398         status = 0;
 399
 400 out:
 401         return status;
 402 }
 403
 404 static __be32 decode_cb_sequence_args(struct svc_rqst *rqstp,
 405                                         struct xdr_stream *xdr,
 406                                         struct cb_sequenceargs *args)
 407 {
 408         __be32 *p;
 409         int i;
 410         __be32 status;
 411
 412         status = decode_sessionid(xdr, &args->csa_sessionid);
 413         if (status)
 414                 return status;
 415
 416         p = read_buf(xdr, 5 * sizeof(uint32_t));
 417         if (unlikely(p == NULL))
 418                 return htonl(NFS4ERR_RESOURCE);
 419
 420         args->csa_addr = svc_addr(rqstp);
 421         args->csa_sequenceid = ntohl(*p++);
 422         args->csa_slotid = ntohl(*p++);
 423         args->csa_highestslotid = ntohl(*p++);
 424         args->csa_cachethis = ntohl(*p++);
 425         args->csa_nrclists = ntohl(*p++);
 426         args->csa_rclists = NULL;
 427         if (args->csa_nrclists) {
 428                 args->csa_rclists = kmalloc_array(args->csa_nrclists,
 429                                                   sizeof(*args->csa_rclists),
 430                                                   GFP_KERNEL);
 431                 if (unlikely(args->csa_rclists == NULL))
 432                         return htonl(NFS4ERR_RESOURCE);
 433
 434                 for (i = 0; i < args->csa_nrclists; i++) {
 435                         status = decode_rc_list(xdr, &args->csa_rclists[i]);
 436                         if (status) {
 437                                 args->csa_nrclists = i;
 438                                 goto out_free;
 439                         }
 440                 }
 441         }
 442         return 0;
 443
 444 out_free:
 445         for (i = 0; i < args->csa_nrclists; i++)
 446                 kfree(args->csa_rclists[i].rcl_refcalls);
 447         kfree(args->csa_rclists);
 448         return status;
 449 }
 450
 451 static __be32 decode_recallany_args(struct svc_rqst *rqstp,
 452                                       struct xdr_stream *xdr,
 453                                       struct cb_recallanyargs *args)
 454 {
 455         uint32_t bitmap[2];
 456         __be32 *p, status;
 457
 458         p = read_buf(xdr, 4);
 459         if (unlikely(p == NULL))
 460                 return htonl(NFS4ERR_BADXDR);
 461         args->craa_objs_to_keep = ntohl(*p++);
 462         status = decode_bitmap(xdr, bitmap);
 463         if (unlikely(status))
 464                 return status;
 465         args->craa_type_mask = bitmap[0];
 466
 467         return 0;
 468 }
 469
 470 static __be32 decode_recallslot_args(struct svc_rqst *rqstp,
 471                                         struct xdr_stream *xdr,
 472                                         struct cb_recallslotargs *args)
 473 {
 474         __be32 *p;
 475
 476         p = read_buf(xdr, 4);
 477         if (unlikely(p == NULL))
 478                 return htonl(NFS4ERR_BADXDR);
 479         args->crsa_target_highest_slotid = ntohl(*p++);
 480         return 0;
 481 }
 482
 483 static __be32 decode_lockowner(struct xdr_stream *xdr, struct cb_notify_lock_args *args)
 484 {
 485         __be32          *p;
 486         unsigned int    len;
 487
 488         p = read_buf(xdr, 12);
 489         if (unlikely(p == NULL))
 490                 return htonl(NFS4ERR_BADXDR);
 491
 492         p = xdr_decode_hyper(p, &args->cbnl_owner.clientid);
 493         len = be32_to_cpu(*p);
 494
 495         p = read_buf(xdr, len);
 496         if (unlikely(p == NULL))
 497                 return htonl(NFS4ERR_BADXDR);
 498
 499         /* Only try to decode if the length is right */
 500         if (len == 20) {
 501                 p += 2; /* skip "lock id:" */
 502                 args->cbnl_owner.s_dev = be32_to_cpu(*p++);
 503                 xdr_decode_hyper(p, &args->cbnl_owner.id);
 504                 args->cbnl_valid = true;
 505         } else {
 506                 args->cbnl_owner.s_dev = 0;
 507                 args->cbnl_owner.id = 0;
 508                 args->cbnl_valid = false;
 509         }
 510         return 0;
 511 }
 512
 513 static __be32 decode_notify_lock_args(struct svc_rqst *rqstp, struct xdr_stream *xdr, struct cb_notify_lock_args *args)
 514 {
 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
 525 static __be32 encode_string(struct xdr_stream *xdr, unsigned int len, const char *str)
 526 {
 527         if (unlikely(xdr_stream_encode_opaque(xdr, str, len) < 0))
 528                 return cpu_to_be32(NFS4ERR_RESOURCE);
 529         return 0;
 530 }
 531
 532 #define CB_SUPPORTED_ATTR0 (FATTR4_WORD0_CHANGE|FATTR4_WORD0_SIZE)
 533 #define CB_SUPPORTED_ATTR1 (FATTR4_WORD1_TIME_METADATA|FATTR4_WORD1_TIME_MODIFY)
 534 static __be32 encode_attr_bitmap(struct xdr_stream *xdr, const uint32_t *bitmap, __be32 **savep)
 535 {
 536         __be32 bm[2];
 537         __be32 *p;
 538
 539         bm[0] = htonl(bitmap[0] & CB_SUPPORTED_ATTR0);
 540         bm[1] = htonl(bitmap[1] & CB_SUPPORTED_ATTR1);
 541         if (bm[1] != 0) {
 542                 p = xdr_reserve_space(xdr, 16);
 543                 if (unlikely(p == NULL))
 544                         return htonl(NFS4ERR_RESOURCE);
 545                 *p++ = htonl(2);
 546                 *p++ = bm[0];
 547                 *p++ = bm[1];
 548         } else if (bm[0] != 0) {
 549                 p = xdr_reserve_space(xdr, 12);
 550                 if (unlikely(p == NULL))
 551                         return htonl(NFS4ERR_RESOURCE);
 552                 *p++ = htonl(1);
 553                 *p++ = bm[0];
 554         } else {
 555                 p = xdr_reserve_space(xdr, 8);
 556                 if (unlikely(p == NULL))
 557                         return htonl(NFS4ERR_RESOURCE);
 558                 *p++ = htonl(0);
 559         }
 560         *savep = p;
 561         return 0;
 562 }
 563
 564 static __be32 encode_attr_change(struct xdr_stream *xdr, const uint32_t *bitmap, uint64_t change)
 565 {
 566         __be32 *p;
 567
 568         if (!(bitmap[0] & FATTR4_WORD0_CHANGE))
 569                 return 0;
 570         p = xdr_reserve_space(xdr, 8);
 571         if (unlikely(!p))
 572                 return htonl(NFS4ERR_RESOURCE);
 573         p = xdr_encode_hyper(p, change);
 574         return 0;
 575 }
 576
 577 static __be32 encode_attr_size(struct xdr_stream *xdr, const uint32_t *bitmap, uint64_t size)
 578 {
 579         __be32 *p;
 580
 581         if (!(bitmap[0] & FATTR4_WORD0_SIZE))
 582                 return 0;
 583         p = xdr_reserve_space(xdr, 8);
 584         if (unlikely(!p))
 585                 return htonl(NFS4ERR_RESOURCE);
 586         p = xdr_encode_hyper(p, size);
 587         return 0;
 588 }
 589
 590 static __be32 encode_attr_time(struct xdr_stream *xdr, const struct timespec *time)
 591 {
 592         __be32 *p;
 593
 594         p = xdr_reserve_space(xdr, 12);
 595         if (unlikely(!p))
 596                 return htonl(NFS4ERR_RESOURCE);
 597         p = xdr_encode_hyper(p, time->tv_sec);
 598         *p = htonl(time->tv_nsec);
 599         return 0;
 600 }
 601
 602 static __be32 encode_attr_ctime(struct xdr_stream *xdr, const uint32_t *bitmap, const struct timespec *time)
 603 {
 604         if (!(bitmap[1] & FATTR4_WORD1_TIME_METADATA))
 605                 return 0;
 606         return encode_attr_time(xdr,time);
 607 }
 608
 609 static __be32 encode_attr_mtime(struct xdr_stream *xdr, const uint32_t *bitmap, const struct timespec *time)
 610 {
 611         if (!(bitmap[1] & FATTR4_WORD1_TIME_MODIFY))
 612                 return 0;
 613         return encode_attr_time(xdr,time);
 614 }
 615
 616 static __be32 encode_compound_hdr_res(struct xdr_stream *xdr, struct cb_compound_hdr_res *hdr)
 617 {
 618         __be32 status;
 619
 620         hdr->status = xdr_reserve_space(xdr, 4);
 621         if (unlikely(hdr->status == NULL))
 622                 return htonl(NFS4ERR_RESOURCE);
 623         status = encode_string(xdr, hdr->taglen, hdr->tag);
 624         if (unlikely(status != 0))
 625                 return status;
 626         hdr->nops = xdr_reserve_space(xdr, 4);
 627         if (unlikely(hdr->nops == NULL))
 628                 return htonl(NFS4ERR_RESOURCE);
 629         return 0;
 630 }
 631
 632 static __be32 encode_op_hdr(struct xdr_stream *xdr, uint32_t op, __be32 res)
 633 {
 634         __be32 *p;
 635
 636         p = xdr_reserve_space(xdr, 8);
 637         if (unlikely(p == NULL))
 638                 return htonl(NFS4ERR_RESOURCE_HDR);
 639         *p++ = htonl(op);
 640         *p = res;
 641         return 0;
 642 }
 643
 644 static __be32 encode_getattr_res(struct svc_rqst *rqstp, struct xdr_stream *xdr, const struct cb_getattrres *res)
 645 {
 646         __be32 *savep = NULL;
 647         __be32 status = res->status;
 648
 649         if (unlikely(status != 0))
 650                 goto out;
 651         status = encode_attr_bitmap(xdr, res->bitmap, &savep);
 652         if (unlikely(status != 0))
 653                 goto out;
 654         status = encode_attr_change(xdr, res->bitmap, res->change_attr);
 655         if (unlikely(status != 0))
 656                 goto out;
 657         status = encode_attr_size(xdr, res->bitmap, res->size);
 658         if (unlikely(status != 0))
 659                 goto out;
 660         status = encode_attr_ctime(xdr, res->bitmap, &res->ctime);
 661         if (unlikely(status != 0))
 662                 goto out;
 663         status = encode_attr_mtime(xdr, res->bitmap, &res->mtime);
 664         *savep = htonl((unsigned int)((char *)xdr->p - (char *)(savep+1)));
 665 out:
 666         return status;
 667 }
 668
 669 #if defined(CONFIG_NFS_V4_1)
 670
 671 static __be32 encode_sessionid(struct xdr_stream *xdr,
 672                                  const struct nfs4_sessionid *sid)
 673 {
 674         __be32 *p;
 675
 676         p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN);
 677         if (unlikely(p == NULL))
 678                 return htonl(NFS4ERR_RESOURCE);
 679
 680         memcpy(p, sid, NFS4_MAX_SESSIONID_LEN);
 681         return 0;
 682 }
 683
 684 static __be32 encode_cb_sequence_res(struct svc_rqst *rqstp,
 685                                        struct xdr_stream *xdr,
 686                                        const struct cb_sequenceres *res)
 687 {
 688         __be32 *p;
 689         __be32 status = res->csr_status;
 690
 691         if (unlikely(status != 0))
 692                 return status;
 693
 694         status = encode_sessionid(xdr, &res->csr_sessionid);
 695         if (status)
 696                 return status;
 697
 698         p = xdr_reserve_space(xdr, 4 * sizeof(uint32_t));
 699         if (unlikely(p == NULL))
 700                 return htonl(NFS4ERR_RESOURCE);
 701
 702         *p++ = htonl(res->csr_sequenceid);
 703         *p++ = htonl(res->csr_slotid);
 704         *p++ = htonl(res->csr_highestslotid);
 705         *p++ = htonl(res->csr_target_highestslotid);
 706         return 0;
 707 }
 708
 709 static __be32
 710 preprocess_nfs41_op(int nop, unsigned int op_nr, struct callback_op **op)
 711 {
 712         if (op_nr == OP_CB_SEQUENCE) {
 713                 if (nop != 0)
 714                         return htonl(NFS4ERR_SEQUENCE_POS);
 715         } else {
 716                 if (nop == 0)
 717                         return htonl(NFS4ERR_OP_NOT_IN_SESSION);
 718         }
 719
 720         switch (op_nr) {
 721         case OP_CB_GETATTR:
 722         case OP_CB_RECALL:
 723         case OP_CB_SEQUENCE:
 724         case OP_CB_RECALL_ANY:
 725         case OP_CB_RECALL_SLOT:
 726         case OP_CB_LAYOUTRECALL:
 727         case OP_CB_NOTIFY_DEVICEID:
 728         case OP_CB_NOTIFY_LOCK:
 729                 *op = &callback_ops[op_nr];
 730                 break;
 731
 732         case OP_CB_NOTIFY:
 733         case OP_CB_PUSH_DELEG:
 734         case OP_CB_RECALLABLE_OBJ_AVAIL:
 735         case OP_CB_WANTS_CANCELLED:
 736                 return htonl(NFS4ERR_NOTSUPP);
 737
 738         default:
 739                 return htonl(NFS4ERR_OP_ILLEGAL);
 740         }
 741
 742         return htonl(NFS_OK);
 743 }
 744
 745 static void nfs4_callback_free_slot(struct nfs4_session *session,
 746                 struct nfs4_slot *slot)
 747 {
 748         struct nfs4_slot_table *tbl = &session->bc_slot_table;
 749
 750         spin_lock(&tbl->slot_tbl_lock);
 751         /*
 752          * Let the state manager know callback processing done.
 753          * A single slot, so highest used slotid is either 0 or -1
 754          */
 755         nfs4_free_slot(tbl, slot);
 756         spin_unlock(&tbl->slot_tbl_lock);
 757 }
 758
 759 static void nfs4_cb_free_slot(struct cb_process_state *cps)
 760 {
 761         if (cps->slot) {
 762                 nfs4_callback_free_slot(cps->clp->cl_session, cps->slot);
 763                 cps->slot = NULL;
 764         }
 765 }
 766
 767 #else /* CONFIG_NFS_V4_1 */
 768
 769 static __be32
 770 preprocess_nfs41_op(int nop, unsigned int op_nr, struct callback_op **op)
 771 {
 772         return htonl(NFS4ERR_MINOR_VERS_MISMATCH);
 773 }
 774
 775 static void nfs4_cb_free_slot(struct cb_process_state *cps)
 776 {
 777 }
 778 #endif /* CONFIG_NFS_V4_1 */
 779
 780 #ifdef CONFIG_NFS_V4_2
 781 static __be32
 782 preprocess_nfs42_op(int nop, unsigned int op_nr, struct callback_op **op)
 783 {
 784         __be32 status = preprocess_nfs41_op(nop, op_nr, op);
 785         if (status != htonl(NFS4ERR_OP_ILLEGAL))
 786                 return status;
 787
 788         if (op_nr == OP_CB_OFFLOAD)
 789                 return htonl(NFS4ERR_NOTSUPP);
 790         return htonl(NFS4ERR_OP_ILLEGAL);
 791 }
 792 #else /* CONFIG_NFS_V4_2 */
 793 static __be32
 794 preprocess_nfs42_op(int nop, unsigned int op_nr, struct callback_op **op)
 795 {
 796         return htonl(NFS4ERR_MINOR_VERS_MISMATCH);
 797 }
 798 #endif /* CONFIG_NFS_V4_2 */
 799
 800 static __be32
 801 preprocess_nfs4_op(unsigned int op_nr, struct callback_op **op)
 802 {
 803         switch (op_nr) {
 804         case OP_CB_GETATTR:
 805         case OP_CB_RECALL:
 806                 *op = &callback_ops[op_nr];
 807                 break;
 808         default:
 809                 return htonl(NFS4ERR_OP_ILLEGAL);
 810         }
 811
 812         return htonl(NFS_OK);
 813 }
 814
 815 static __be32 process_op(int nop, struct svc_rqst *rqstp,
 816                 struct xdr_stream *xdr_in, void *argp,
 817                 struct xdr_stream *xdr_out, void *resp,
 818                 struct cb_process_state *cps)
 819 {
 820         struct callback_op *op = &callback_ops[0];
 821         unsigned int op_nr;
 822         __be32 status;
 823         long maxlen;
 824         __be32 res;
 825
 826         status = decode_op_hdr(xdr_in, &op_nr);
 827         if (unlikely(status))
 828                 return status;
 829
 830         switch (cps->minorversion) {
 831         case 0:
 832                 status = preprocess_nfs4_op(op_nr, &op);
 833                 break;
 834         case 1:
 835                 status = preprocess_nfs41_op(nop, op_nr, &op);
 836                 break;
 837         case 2:
 838                 status = preprocess_nfs42_op(nop, op_nr, &op);
 839                 break;
 840         default:
 841                 status = htonl(NFS4ERR_MINOR_VERS_MISMATCH);
 842         }
 843
 844         if (status == htonl(NFS4ERR_OP_ILLEGAL))
 845                 op_nr = OP_CB_ILLEGAL;
 846         if (status)
 847                 goto encode_hdr;
 848
 849         if (cps->drc_status) {
 850                 status = cps->drc_status;
 851                 goto encode_hdr;
 852         }
 853
 854         maxlen = xdr_out->end - xdr_out->p;
 855         if (maxlen > 0 && maxlen < PAGE_SIZE) {
 856                 status = op->decode_args(rqstp, xdr_in, argp);
 857                 if (likely(status == 0))
 858                         status = op->process_op(argp, resp, cps);
 859         } else
 860                 status = htonl(NFS4ERR_RESOURCE);
 861
 862 encode_hdr:
 863         res = encode_op_hdr(xdr_out, op_nr, status);
 864         if (unlikely(res))
 865                 return res;
 866         if (op->encode_res != NULL && status == 0)
 867                 status = op->encode_res(rqstp, xdr_out, resp);
 868         return status;
 869 }
 870
 871 /*
 872  * Decode, process and encode a COMPOUND
 873  */
 874 static __be32 nfs4_callback_compound(struct svc_rqst *rqstp, void *argp, void *resp)
 875 {
 876         struct cb_compound_hdr_arg hdr_arg = { 0 };
 877         struct cb_compound_hdr_res hdr_res = { NULL };
 878         struct xdr_stream xdr_in, xdr_out;
 879         __be32 *p, status;
 880         struct cb_process_state cps = {
 881                 .drc_status = 0,
 882                 .clp = NULL,
 883                 .net = SVC_NET(rqstp),
 884         };
 885         unsigned int nops = 0;
 886
 887         xdr_init_decode(&xdr_in, &rqstp->rq_arg, rqstp->rq_arg.head[0].iov_base);
 888
 889         p = (__be32*)((char *)rqstp->rq_res.head[0].iov_base + rqstp->rq_res.head[0].iov_len);
 890         xdr_init_encode(&xdr_out, &rqstp->rq_res, p);
 891
 892         status = decode_compound_hdr_arg(&xdr_in, &hdr_arg);
 893         if (status == htonl(NFS4ERR_RESOURCE))
 894                 return rpc_garbage_args;
 895
 896         if (hdr_arg.minorversion == 0) {
 897                 cps.clp = nfs4_find_client_ident(SVC_NET(rqstp), hdr_arg.cb_ident);
 898                 if (!cps.clp || !check_gss_callback_principal(cps.clp, rqstp))
 899                         goto out_invalidcred;
 900         }
 901
 902         cps.minorversion = hdr_arg.minorversion;
 903         hdr_res.taglen = hdr_arg.taglen;
 904         hdr_res.tag = hdr_arg.tag;
 905         if (encode_compound_hdr_res(&xdr_out, &hdr_res) != 0)
 906                 return rpc_system_err;
 907
 908         while (status == 0 && nops != hdr_arg.nops) {
 909                 status = process_op(nops, rqstp, &xdr_in,
 910                                     argp, &xdr_out, resp, &cps);
 911                 nops++;
 912         }
 913
 914         /* Buffer overflow in decode_ops_hdr or encode_ops_hdr. Return
 915         * resource error in cb_compound status without returning op */
 916         if (unlikely(status == htonl(NFS4ERR_RESOURCE_HDR))) {
 917                 status = htonl(NFS4ERR_RESOURCE);
 918                 nops--;
 919         }
 920
 921         *hdr_res.status = status;
 922         *hdr_res.nops = htonl(nops);
 923         nfs4_cb_free_slot(&cps);
 924         nfs_put_client(cps.clp);
 925         return rpc_success;
 926
 927 out_invalidcred:
 928         pr_warn_ratelimited("NFS: NFSv4 callback contains invalid cred\n");
 929         return rpc_autherr_badcred;
 930 }
 931
 932 /*
 933  * Define NFS4 callback COMPOUND ops.
 934  */
 935 static struct callback_op callback_ops[] = {
 936         [0] = {
 937                 .res_maxsize = CB_OP_HDR_RES_MAXSZ,
 938         },
 939         [OP_CB_GETATTR] = {
 940                 .process_op = (callback_process_op_t)nfs4_callback_getattr,
 941                 .decode_args = (callback_decode_arg_t)decode_getattr_args,
 942                 .encode_res = (callback_encode_res_t)encode_getattr_res,
 943                 .res_maxsize = CB_OP_GETATTR_RES_MAXSZ,
 944         },
 945         [OP_CB_RECALL] = {
 946                 .process_op = (callback_process_op_t)nfs4_callback_recall,
 947                 .decode_args = (callback_decode_arg_t)decode_recall_args,
 948                 .res_maxsize = CB_OP_RECALL_RES_MAXSZ,
 949         },
 950 #if defined(CONFIG_NFS_V4_1)
 951         [OP_CB_LAYOUTRECALL] = {
 952                 .process_op = (callback_process_op_t)nfs4_callback_layoutrecall,
 953                 .decode_args =
 954                         (callback_decode_arg_t)decode_layoutrecall_args,
 955                 .res_maxsize = CB_OP_LAYOUTRECALL_RES_MAXSZ,
 956         },
 957         [OP_CB_NOTIFY_DEVICEID] = {
 958                 .process_op = (callback_process_op_t)nfs4_callback_devicenotify,
 959                 .decode_args =
 960                         (callback_decode_arg_t)decode_devicenotify_args,
 961                 .res_maxsize = CB_OP_DEVICENOTIFY_RES_MAXSZ,
 962         },
 963         [OP_CB_SEQUENCE] = {
 964                 .process_op = (callback_process_op_t)nfs4_callback_sequence,
 965                 .decode_args = (callback_decode_arg_t)decode_cb_sequence_args,
 966                 .encode_res = (callback_encode_res_t)encode_cb_sequence_res,
 967                 .res_maxsize = CB_OP_SEQUENCE_RES_MAXSZ,
 968         },
 969         [OP_CB_RECALL_ANY] = {
 970                 .process_op = (callback_process_op_t)nfs4_callback_recallany,
 971                 .decode_args = (callback_decode_arg_t)decode_recallany_args,
 972                 .res_maxsize = CB_OP_RECALLANY_RES_MAXSZ,
 973         },
 974         [OP_CB_RECALL_SLOT] = {
 975                 .process_op = (callback_process_op_t)nfs4_callback_recallslot,
 976                 .decode_args = (callback_decode_arg_t)decode_recallslot_args,
 977                 .res_maxsize = CB_OP_RECALLSLOT_RES_MAXSZ,
 978         },
 979         [OP_CB_NOTIFY_LOCK] = {
 980                 .process_op = (callback_process_op_t)nfs4_callback_notify_lock,
 981                 .decode_args = (callback_decode_arg_t)decode_notify_lock_args,
 982                 .res_maxsize = CB_OP_NOTIFY_LOCK_RES_MAXSZ,
 983         },
 984 #endif /* CONFIG_NFS_V4_1 */
 985 };
 986
 987 /*
 988  * Define NFS4 callback procedures
 989  */
 990 static struct svc_procedure nfs4_callback_procedures1[] = {
 991         [CB_NULL] = {
 992                 .pc_func = nfs4_callback_null,
 993                 .pc_decode = (kxdrproc_t)nfs4_decode_void,
 994                 .pc_encode = (kxdrproc_t)nfs4_encode_void,
 995                 .pc_xdrressize = 1,
 996         },
 997         [CB_COMPOUND] = {
 998                 .pc_func = nfs4_callback_compound,
 999                 .pc_encode = (kxdrproc_t)nfs4_encode_void,
1000                 .pc_argsize = 256,
1001                 .pc_ressize = 256,
1002                 .pc_xdrressize = NFS4_CALLBACK_BUFSIZE,
1003         }
1004 };
1005
1006 struct svc_version nfs4_callback_version1 = {
1007         .vs_vers = 1,
1008         .vs_nproc = ARRAY_SIZE(nfs4_callback_procedures1),
1009         .vs_proc = nfs4_callback_procedures1,
1010         .vs_xdrsize = NFS4_CALLBACK_XDRSIZE,
1011         .vs_dispatch = NULL,
1012         .vs_hidden = true,
1013         .vs_need_cong_ctrl = true,
1014 };
1015
1016 struct svc_version nfs4_callback_version4 = {
1017         .vs_vers = 4,
1018         .vs_nproc = ARRAY_SIZE(nfs4_callback_procedures1),
1019         .vs_proc = nfs4_callback_procedures1,
1020         .vs_xdrsize = NFS4_CALLBACK_XDRSIZE,
1021         .vs_dispatch = NULL,
1022         .vs_hidden = true,
1023         .vs_need_cong_ctrl = true,
1024 };