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 #endif /* CONFIG_NFS_V4_1 */
  39
  40 #define NFSDBG_FACILITY NFSDBG_CALLBACK
  41
  42 /* Internal error code */
  43 #define NFS4ERR_RESOURCE_HDR    11050
  44
  45 typedef __be32 (*callback_process_op_t)(void *, void *,
  46                                         struct cb_process_state *);
  47 typedef __be32 (*callback_decode_arg_t)(struct svc_rqst *, struct xdr_stream *, void *);
  48 typedef __be32 (*callback_encode_res_t)(struct svc_rqst *, struct xdr_stream *, void *);
  49
  50
  51 struct callback_op {
  52         callback_process_op_t process_op;
  53         callback_decode_arg_t decode_args;
  54         callback_encode_res_t encode_res;
  55         long res_maxsize;
  56 };
  57
  58 static struct callback_op callback_ops[];
  59
  60 static __be32 nfs4_callback_null(struct svc_rqst *rqstp, void *argp, void *resp)
  61 {
  62         return htonl(NFS4_OK);
  63 }
  64
  65 static int nfs4_decode_void(struct svc_rqst *rqstp, __be32 *p, void *dummy)
  66 {
  67         return xdr_argsize_check(rqstp, p);
  68 }
  69
  70 static int nfs4_encode_void(struct svc_rqst *rqstp, __be32 *p, void *dummy)
  71 {
  72         return xdr_ressize_check(rqstp, p);
  73 }
  74
  75 static __be32 *read_buf(struct xdr_stream *xdr, int nbytes)
  76 {
  77         __be32 *p;
  78
  79         p = xdr_inline_decode(xdr, nbytes);
  80         if (unlikely(p == NULL))
  81                 printk(KERN_WARNING "NFS: NFSv4 callback reply buffer overflowed "
  82                                                         "or truncated request.\n");
  83         return p;
  84 }
  85
  86 static __be32 decode_string(struct xdr_stream *xdr, unsigned int *len, const char **str)
  87 {
  88         __be32 *p;
  89
  90         p = read_buf(xdr, 4);
  91         if (unlikely(p == NULL))
  92                 return htonl(NFS4ERR_RESOURCE);
  93         *len = ntohl(*p);
  94
  95         if (*len != 0) {
  96                 p = read_buf(xdr, *len);
  97                 if (unlikely(p == NULL))
  98                         return htonl(NFS4ERR_RESOURCE);
  99                 *str = (const char *)p;
 100         } else
 101                 *str = NULL;
 102
 103         return 0;
 104 }
 105
 106 static __be32 decode_fh(struct xdr_stream *xdr, struct nfs_fh *fh)
 107 {
 108         __be32 *p;
 109
 110         p = read_buf(xdr, 4);
 111         if (unlikely(p == NULL))
 112                 return htonl(NFS4ERR_RESOURCE);
 113         fh->size = ntohl(*p);
 114         if (fh->size > NFS4_FHSIZE)
 115                 return htonl(NFS4ERR_BADHANDLE);
 116         p = read_buf(xdr, fh->size);
 117         if (unlikely(p == NULL))
 118                 return htonl(NFS4ERR_RESOURCE);
 119         memcpy(&fh->data[0], p, fh->size);
 120         memset(&fh->data[fh->size], 0, sizeof(fh->data) - fh->size);
 121         return 0;
 122 }
 123
 124 static __be32 decode_bitmap(struct xdr_stream *xdr, uint32_t *bitmap)
 125 {
 126         __be32 *p;
 127         unsigned int attrlen;
 128
 129         p = read_buf(xdr, 4);
 130         if (unlikely(p == NULL))
 131                 return htonl(NFS4ERR_RESOURCE);
 132         attrlen = ntohl(*p);
 133         p = read_buf(xdr, attrlen << 2);
 134         if (unlikely(p == NULL))
 135                 return htonl(NFS4ERR_RESOURCE);
 136         if (likely(attrlen > 0))
 137                 bitmap[0] = ntohl(*p++);
 138         if (attrlen > 1)
 139                 bitmap[1] = ntohl(*p);
 140         return 0;
 141 }
 142
 143 static __be32 decode_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
 144 {
 145         __be32 *p;
 146
 147         p = read_buf(xdr, NFS4_STATEID_SIZE);
 148         if (unlikely(p == NULL))
 149                 return htonl(NFS4ERR_RESOURCE);
 150         memcpy(stateid, p, NFS4_STATEID_SIZE);
 151         return 0;
 152 }
 153
 154 static __be32 decode_compound_hdr_arg(struct xdr_stream *xdr, struct cb_compound_hdr_arg *hdr)
 155 {
 156         __be32 *p;
 157         __be32 status;
 158
 159         status = decode_string(xdr, &hdr->taglen, &hdr->tag);
 160         if (unlikely(status != 0))
 161                 return status;
 162         /* We do not like overly long tags! */
 163         if (hdr->taglen > CB_OP_TAGLEN_MAXSZ) {
 164                 printk("NFS: NFSv4 CALLBACK %s: client sent tag of length %u\n",
 165                                 __func__, hdr->taglen);
 166                 return htonl(NFS4ERR_RESOURCE);
 167         }
 168         p = read_buf(xdr, 12);
 169         if (unlikely(p == NULL))
 170                 return htonl(NFS4ERR_RESOURCE);
 171         hdr->minorversion = ntohl(*p++);
 172         /* Check for minor version support */
 173         if (hdr->minorversion <= NFS4_MAX_MINOR_VERSION) {
 174                 hdr->cb_ident = ntohl(*p++); /* ignored by v4.1 and v4.2 */
 175         } else {
 176                 pr_warn_ratelimited("NFS: %s: NFSv4 server callback with "
 177                         "illegal minor version %u!\n",
 178                         __func__, hdr->minorversion);
 179                 return htonl(NFS4ERR_MINOR_VERS_MISMATCH);
 180         }
 181         hdr->nops = ntohl(*p);
 182         dprintk("%s: minorversion %d nops %d\n", __func__,
 183                 hdr->minorversion, hdr->nops);
 184         return 0;
 185 }
 186
 187 static __be32 decode_op_hdr(struct xdr_stream *xdr, unsigned int *op)
 188 {
 189         __be32 *p;
 190         p = read_buf(xdr, 4);
 191         if (unlikely(p == NULL))
 192                 return htonl(NFS4ERR_RESOURCE_HDR);
 193         *op = ntohl(*p);
 194         return 0;
 195 }
 196
 197 static __be32 decode_getattr_args(struct svc_rqst *rqstp, struct xdr_stream *xdr, struct cb_getattrargs *args)
 198 {
 199         __be32 status;
 200
 201         status = decode_fh(xdr, &args->fh);
 202         if (unlikely(status != 0))
 203                 goto out;
 204         status = decode_bitmap(xdr, args->bitmap);
 205 out:
 206         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 207         return status;
 208 }
 209
 210 static __be32 decode_recall_args(struct svc_rqst *rqstp, struct xdr_stream *xdr, struct cb_recallargs *args)
 211 {
 212         __be32 *p;
 213         __be32 status;
 214
 215         status = decode_stateid(xdr, &args->stateid);
 216         if (unlikely(status != 0))
 217                 goto out;
 218         p = read_buf(xdr, 4);
 219         if (unlikely(p == NULL)) {
 220                 status = htonl(NFS4ERR_RESOURCE);
 221                 goto out;
 222         }
 223         args->truncate = ntohl(*p);
 224         status = decode_fh(xdr, &args->fh);
 225 out:
 226         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 227         return status;
 228 }
 229
 230 #if defined(CONFIG_NFS_V4_1)
 231
 232 static __be32 decode_layoutrecall_args(struct svc_rqst *rqstp,
 233                                        struct xdr_stream *xdr,
 234                                        struct cb_layoutrecallargs *args)
 235 {
 236         __be32 *p;
 237         __be32 status = 0;
 238         uint32_t iomode;
 239
 240         p = read_buf(xdr, 4 * sizeof(uint32_t));
 241         if (unlikely(p == NULL)) {
 242                 status = htonl(NFS4ERR_BADXDR);
 243                 goto out;
 244         }
 245
 246         args->cbl_layout_type = ntohl(*p++);
 247         /* Depite the spec's xdr, iomode really belongs in the FILE switch,
 248          * as it is unusable and ignored with the other types.
 249          */
 250         iomode = ntohl(*p++);
 251         args->cbl_layoutchanged = ntohl(*p++);
 252         args->cbl_recall_type = ntohl(*p++);
 253
 254         if (args->cbl_recall_type == RETURN_FILE) {
 255                 args->cbl_range.iomode = iomode;
 256                 status = decode_fh(xdr, &args->cbl_fh);
 257                 if (unlikely(status != 0))
 258                         goto out;
 259
 260                 p = read_buf(xdr, 2 * sizeof(uint64_t));
 261                 if (unlikely(p == NULL)) {
 262                         status = htonl(NFS4ERR_BADXDR);
 263                         goto out;
 264                 }
 265                 p = xdr_decode_hyper(p, &args->cbl_range.offset);
 266                 p = xdr_decode_hyper(p, &args->cbl_range.length);
 267                 status = decode_stateid(xdr, &args->cbl_stateid);
 268                 if (unlikely(status != 0))
 269                         goto out;
 270         } else if (args->cbl_recall_type == RETURN_FSID) {
 271                 p = read_buf(xdr, 2 * sizeof(uint64_t));
 272                 if (unlikely(p == NULL)) {
 273                         status = htonl(NFS4ERR_BADXDR);
 274                         goto out;
 275                 }
 276                 p = xdr_decode_hyper(p, &args->cbl_fsid.major);
 277                 p = xdr_decode_hyper(p, &args->cbl_fsid.minor);
 278         } else if (args->cbl_recall_type != RETURN_ALL) {
 279                 status = htonl(NFS4ERR_BADXDR);
 280                 goto out;
 281         }
 282         dprintk("%s: ltype 0x%x iomode %d changed %d recall_type %d\n",
 283                 __func__,
 284                 args->cbl_layout_type, iomode,
 285                 args->cbl_layoutchanged, args->cbl_recall_type);
 286 out:
 287         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 288         return status;
 289 }
 290
 291 static
 292 __be32 decode_devicenotify_args(struct svc_rqst *rqstp,
 293                                 struct xdr_stream *xdr,
 294                                 struct cb_devicenotifyargs *args)
 295 {
 296         __be32 *p;
 297         __be32 status = 0;
 298         u32 tmp;
 299         int n, i;
 300         args->ndevs = 0;
 301
 302         /* Num of device notifications */
 303         p = read_buf(xdr, sizeof(uint32_t));
 304         if (unlikely(p == NULL)) {
 305                 status = htonl(NFS4ERR_BADXDR);
 306                 goto out;
 307         }
 308         n = ntohl(*p++);
 309         if (n <= 0)
 310                 goto out;
 311         if (n > ULONG_MAX / sizeof(*args->devs)) {
 312                 status = htonl(NFS4ERR_BADXDR);
 313                 goto out;
 314         }
 315
 316         args->devs = kmalloc_array(n, sizeof(*args->devs), GFP_KERNEL);
 317         if (!args->devs) {
 318                 status = htonl(NFS4ERR_DELAY);
 319                 goto out;
 320         }
 321
 322         /* Decode each dev notification */
 323         for (i = 0; i < n; i++) {
 324                 struct cb_devicenotifyitem *dev = &args->devs[i];
 325
 326                 p = read_buf(xdr, (4 * sizeof(uint32_t)) + NFS4_DEVICEID4_SIZE);
 327                 if (unlikely(p == NULL)) {
 328                         status = htonl(NFS4ERR_BADXDR);
 329                         goto err;
 330                 }
 331
 332                 tmp = ntohl(*p++);      /* bitmap size */
 333                 if (tmp != 1) {
 334                         status = htonl(NFS4ERR_INVAL);
 335                         goto err;
 336                 }
 337                 dev->cbd_notify_type = ntohl(*p++);
 338                 if (dev->cbd_notify_type != NOTIFY_DEVICEID4_CHANGE &&
 339                     dev->cbd_notify_type != NOTIFY_DEVICEID4_DELETE) {
 340                         status = htonl(NFS4ERR_INVAL);
 341                         goto err;
 342                 }
 343
 344                 tmp = ntohl(*p++);      /* opaque size */
 345                 if (((dev->cbd_notify_type == NOTIFY_DEVICEID4_CHANGE) &&
 346                      (tmp != NFS4_DEVICEID4_SIZE + 8)) ||
 347                     ((dev->cbd_notify_type == NOTIFY_DEVICEID4_DELETE) &&
 348                      (tmp != NFS4_DEVICEID4_SIZE + 4))) {
 349                         status = htonl(NFS4ERR_INVAL);
 350                         goto err;
 351                 }
 352                 dev->cbd_layout_type = ntohl(*p++);
 353                 memcpy(dev->cbd_dev_id.data, p, NFS4_DEVICEID4_SIZE);
 354                 p += XDR_QUADLEN(NFS4_DEVICEID4_SIZE);
 355
 356                 if (dev->cbd_layout_type == NOTIFY_DEVICEID4_CHANGE) {
 357                         p = read_buf(xdr, sizeof(uint32_t));
 358                         if (unlikely(p == NULL)) {
 359                                 status = htonl(NFS4ERR_BADXDR);
 360                                 goto err;
 361                         }
 362                         dev->cbd_immediate = ntohl(*p++);
 363                 } else {
 364                         dev->cbd_immediate = 0;
 365                 }
 366
 367                 args->ndevs++;
 368
 369                 dprintk("%s: type %d layout 0x%x immediate %d\n",
 370                         __func__, dev->cbd_notify_type, dev->cbd_layout_type,
 371                         dev->cbd_immediate);
 372         }
 373 out:
 374         dprintk("%s: status %d ndevs %d\n",
 375                 __func__, ntohl(status), args->ndevs);
 376         return status;
 377 err:
 378         kfree(args->devs);
 379         goto out;
 380 }
 381
 382 static __be32 decode_sessionid(struct xdr_stream *xdr,
 383                                  struct nfs4_sessionid *sid)
 384 {
 385         __be32 *p;
 386
 387         p = read_buf(xdr, NFS4_MAX_SESSIONID_LEN);
 388         if (unlikely(p == NULL))
 389                 return htonl(NFS4ERR_RESOURCE);
 390
 391         memcpy(sid->data, p, NFS4_MAX_SESSIONID_LEN);
 392         return 0;
 393 }
 394
 395 static __be32 decode_rc_list(struct xdr_stream *xdr,
 396                                struct referring_call_list *rc_list)
 397 {
 398         __be32 *p;
 399         int i;
 400         __be32 status;
 401
 402         status = decode_sessionid(xdr, &rc_list->rcl_sessionid);
 403         if (status)
 404                 goto out;
 405
 406         status = htonl(NFS4ERR_RESOURCE);
 407         p = read_buf(xdr, sizeof(uint32_t));
 408         if (unlikely(p == NULL))
 409                 goto out;
 410
 411         rc_list->rcl_nrefcalls = ntohl(*p++);
 412         if (rc_list->rcl_nrefcalls) {
 413                 p = read_buf(xdr,
 414                              rc_list->rcl_nrefcalls * 2 * sizeof(uint32_t));
 415                 if (unlikely(p == NULL))
 416                         goto out;
 417                 rc_list->rcl_refcalls = kmalloc_array(rc_list->rcl_nrefcalls,
 418                                                 sizeof(*rc_list->rcl_refcalls),
 419                                                 GFP_KERNEL);
 420                 if (unlikely(rc_list->rcl_refcalls == NULL))
 421                         goto out;
 422                 for (i = 0; i < rc_list->rcl_nrefcalls; i++) {
 423                         rc_list->rcl_refcalls[i].rc_sequenceid = ntohl(*p++);
 424                         rc_list->rcl_refcalls[i].rc_slotid = ntohl(*p++);
 425                 }
 426         }
 427         status = 0;
 428
 429 out:
 430         return status;
 431 }
 432
 433 static __be32 decode_cb_sequence_args(struct svc_rqst *rqstp,
 434                                         struct xdr_stream *xdr,
 435                                         struct cb_sequenceargs *args)
 436 {
 437         __be32 *p;
 438         int i;
 439         __be32 status;
 440
 441         status = decode_sessionid(xdr, &args->csa_sessionid);
 442         if (status)
 443                 goto out;
 444
 445         status = htonl(NFS4ERR_RESOURCE);
 446         p = read_buf(xdr, 5 * sizeof(uint32_t));
 447         if (unlikely(p == NULL))
 448                 goto out;
 449
 450         args->csa_addr = svc_addr(rqstp);
 451         args->csa_sequenceid = ntohl(*p++);
 452         args->csa_slotid = ntohl(*p++);
 453         args->csa_highestslotid = ntohl(*p++);
 454         args->csa_cachethis = ntohl(*p++);
 455         args->csa_nrclists = ntohl(*p++);
 456         args->csa_rclists = NULL;
 457         if (args->csa_nrclists) {
 458                 args->csa_rclists = kmalloc_array(args->csa_nrclists,
 459                                                   sizeof(*args->csa_rclists),
 460                                                   GFP_KERNEL);
 461                 if (unlikely(args->csa_rclists == NULL))
 462                         goto out;
 463
 464                 for (i = 0; i < args->csa_nrclists; i++) {
 465                         status = decode_rc_list(xdr, &args->csa_rclists[i]);
 466                         if (status) {
 467                                 args->csa_nrclists = i;
 468                                 goto out_free;
 469                         }
 470                 }
 471         }
 472         status = 0;
 473
 474         dprintk("%s: sessionid %x:%x:%x:%x sequenceid %u slotid %u "
 475                 "highestslotid %u cachethis %d nrclists %u\n",
 476                 __func__,
 477                 ((u32 *)&args->csa_sessionid)[0],
 478                 ((u32 *)&args->csa_sessionid)[1],
 479                 ((u32 *)&args->csa_sessionid)[2],
 480                 ((u32 *)&args->csa_sessionid)[3],
 481                 args->csa_sequenceid, args->csa_slotid,
 482                 args->csa_highestslotid, args->csa_cachethis,
 483                 args->csa_nrclists);
 484 out:
 485         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 486         return status;
 487
 488 out_free:
 489         for (i = 0; i < args->csa_nrclists; i++)
 490                 kfree(args->csa_rclists[i].rcl_refcalls);
 491         kfree(args->csa_rclists);
 492         goto out;
 493 }
 494
 495 static __be32 decode_recallany_args(struct svc_rqst *rqstp,
 496                                       struct xdr_stream *xdr,
 497                                       struct cb_recallanyargs *args)
 498 {
 499         uint32_t bitmap[2];
 500         __be32 *p, status;
 501
 502         p = read_buf(xdr, 4);
 503         if (unlikely(p == NULL))
 504                 return htonl(NFS4ERR_BADXDR);
 505         args->craa_objs_to_keep = ntohl(*p++);
 506         status = decode_bitmap(xdr, bitmap);
 507         if (unlikely(status))
 508                 return status;
 509         args->craa_type_mask = bitmap[0];
 510
 511         return 0;
 512 }
 513
 514 static __be32 decode_recallslot_args(struct svc_rqst *rqstp,
 515                                         struct xdr_stream *xdr,
 516                                         struct cb_recallslotargs *args)
 517 {
 518         __be32 *p;
 519
 520         p = read_buf(xdr, 4);
 521         if (unlikely(p == NULL))
 522                 return htonl(NFS4ERR_BADXDR);
 523         args->crsa_target_highest_slotid = ntohl(*p++);
 524         return 0;
 525 }
 526
 527 #endif /* CONFIG_NFS_V4_1 */
 528
 529 static __be32 encode_string(struct xdr_stream *xdr, unsigned int len, const char *str)
 530 {
 531         __be32 *p;
 532
 533         p = xdr_reserve_space(xdr, 4 + len);
 534         if (unlikely(p == NULL))
 535                 return htonl(NFS4ERR_RESOURCE);
 536         xdr_encode_opaque(p, str, len);
 537         return 0;
 538 }
 539
 540 #define CB_SUPPORTED_ATTR0 (FATTR4_WORD0_CHANGE|FATTR4_WORD0_SIZE)
 541 #define CB_SUPPORTED_ATTR1 (FATTR4_WORD1_TIME_METADATA|FATTR4_WORD1_TIME_MODIFY)
 542 static __be32 encode_attr_bitmap(struct xdr_stream *xdr, const uint32_t *bitmap, __be32 **savep)
 543 {
 544         __be32 bm[2];
 545         __be32 *p;
 546
 547         bm[0] = htonl(bitmap[0] & CB_SUPPORTED_ATTR0);
 548         bm[1] = htonl(bitmap[1] & CB_SUPPORTED_ATTR1);
 549         if (bm[1] != 0) {
 550                 p = xdr_reserve_space(xdr, 16);
 551                 if (unlikely(p == NULL))
 552                         return htonl(NFS4ERR_RESOURCE);
 553                 *p++ = htonl(2);
 554                 *p++ = bm[0];
 555                 *p++ = bm[1];
 556         } else if (bm[0] != 0) {
 557                 p = xdr_reserve_space(xdr, 12);
 558                 if (unlikely(p == NULL))
 559                         return htonl(NFS4ERR_RESOURCE);
 560                 *p++ = htonl(1);
 561                 *p++ = bm[0];
 562         } else {
 563                 p = xdr_reserve_space(xdr, 8);
 564                 if (unlikely(p == NULL))
 565                         return htonl(NFS4ERR_RESOURCE);
 566                 *p++ = htonl(0);
 567         }
 568         *savep = p;
 569         return 0;
 570 }
 571
 572 static __be32 encode_attr_change(struct xdr_stream *xdr, const uint32_t *bitmap, uint64_t change)
 573 {
 574         __be32 *p;
 575
 576         if (!(bitmap[0] & FATTR4_WORD0_CHANGE))
 577                 return 0;
 578         p = xdr_reserve_space(xdr, 8);
 579         if (unlikely(!p))
 580                 return htonl(NFS4ERR_RESOURCE);
 581         p = xdr_encode_hyper(p, change);
 582         return 0;
 583 }
 584
 585 static __be32 encode_attr_size(struct xdr_stream *xdr, const uint32_t *bitmap, uint64_t size)
 586 {
 587         __be32 *p;
 588
 589         if (!(bitmap[0] & FATTR4_WORD0_SIZE))
 590                 return 0;
 591         p = xdr_reserve_space(xdr, 8);
 592         if (unlikely(!p))
 593                 return htonl(NFS4ERR_RESOURCE);
 594         p = xdr_encode_hyper(p, size);
 595         return 0;
 596 }
 597
 598 static __be32 encode_attr_time(struct xdr_stream *xdr, const struct timespec *time)
 599 {
 600         __be32 *p;
 601
 602         p = xdr_reserve_space(xdr, 12);
 603         if (unlikely(!p))
 604                 return htonl(NFS4ERR_RESOURCE);
 605         p = xdr_encode_hyper(p, time->tv_sec);
 606         *p = htonl(time->tv_nsec);
 607         return 0;
 608 }
 609
 610 static __be32 encode_attr_ctime(struct xdr_stream *xdr, const uint32_t *bitmap, const struct timespec *time)
 611 {
 612         if (!(bitmap[1] & FATTR4_WORD1_TIME_METADATA))
 613                 return 0;
 614         return encode_attr_time(xdr,time);
 615 }
 616
 617 static __be32 encode_attr_mtime(struct xdr_stream *xdr, const uint32_t *bitmap, const struct timespec *time)
 618 {
 619         if (!(bitmap[1] & FATTR4_WORD1_TIME_MODIFY))
 620                 return 0;
 621         return encode_attr_time(xdr,time);
 622 }
 623
 624 static __be32 encode_compound_hdr_res(struct xdr_stream *xdr, struct cb_compound_hdr_res *hdr)
 625 {
 626         __be32 status;
 627
 628         hdr->status = xdr_reserve_space(xdr, 4);
 629         if (unlikely(hdr->status == NULL))
 630                 return htonl(NFS4ERR_RESOURCE);
 631         status = encode_string(xdr, hdr->taglen, hdr->tag);
 632         if (unlikely(status != 0))
 633                 return status;
 634         hdr->nops = xdr_reserve_space(xdr, 4);
 635         if (unlikely(hdr->nops == NULL))
 636                 return htonl(NFS4ERR_RESOURCE);
 637         return 0;
 638 }
 639
 640 static __be32 encode_op_hdr(struct xdr_stream *xdr, uint32_t op, __be32 res)
 641 {
 642         __be32 *p;
 643
 644         p = xdr_reserve_space(xdr, 8);
 645         if (unlikely(p == NULL))
 646                 return htonl(NFS4ERR_RESOURCE_HDR);
 647         *p++ = htonl(op);
 648         *p = res;
 649         return 0;
 650 }
 651
 652 static __be32 encode_getattr_res(struct svc_rqst *rqstp, struct xdr_stream *xdr, const struct cb_getattrres *res)
 653 {
 654         __be32 *savep = NULL;
 655         __be32 status = res->status;
 656
 657         if (unlikely(status != 0))
 658                 goto out;
 659         status = encode_attr_bitmap(xdr, res->bitmap, &savep);
 660         if (unlikely(status != 0))
 661                 goto out;
 662         status = encode_attr_change(xdr, res->bitmap, res->change_attr);
 663         if (unlikely(status != 0))
 664                 goto out;
 665         status = encode_attr_size(xdr, res->bitmap, res->size);
 666         if (unlikely(status != 0))
 667                 goto out;
 668         status = encode_attr_ctime(xdr, res->bitmap, &res->ctime);
 669         if (unlikely(status != 0))
 670                 goto out;
 671         status = encode_attr_mtime(xdr, res->bitmap, &res->mtime);
 672         *savep = htonl((unsigned int)((char *)xdr->p - (char *)(savep+1)));
 673 out:
 674         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 675         return status;
 676 }
 677
 678 #if defined(CONFIG_NFS_V4_1)
 679
 680 static __be32 encode_sessionid(struct xdr_stream *xdr,
 681                                  const struct nfs4_sessionid *sid)
 682 {
 683         __be32 *p;
 684
 685         p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN);
 686         if (unlikely(p == NULL))
 687                 return htonl(NFS4ERR_RESOURCE);
 688
 689         memcpy(p, sid, NFS4_MAX_SESSIONID_LEN);
 690         return 0;
 691 }
 692
 693 static __be32 encode_cb_sequence_res(struct svc_rqst *rqstp,
 694                                        struct xdr_stream *xdr,
 695                                        const struct cb_sequenceres *res)
 696 {
 697         __be32 *p;
 698         __be32 status = res->csr_status;
 699
 700         if (unlikely(status != 0))
 701                 goto out;
 702
 703         status = encode_sessionid(xdr, &res->csr_sessionid);
 704         if (status)
 705                 goto out;
 706
 707         p = xdr_reserve_space(xdr, 4 * sizeof(uint32_t));
 708         if (unlikely(p == NULL))
 709                 return htonl(NFS4ERR_RESOURCE);
 710
 711         *p++ = htonl(res->csr_sequenceid);
 712         *p++ = htonl(res->csr_slotid);
 713         *p++ = htonl(res->csr_highestslotid);
 714         *p++ = htonl(res->csr_target_highestslotid);
 715 out:
 716         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 717         return status;
 718 }
 719
 720 static __be32
 721 preprocess_nfs41_op(int nop, unsigned int op_nr, struct callback_op **op)
 722 {
 723         if (op_nr == OP_CB_SEQUENCE) {
 724                 if (nop != 0)
 725                         return htonl(NFS4ERR_SEQUENCE_POS);
 726         } else {
 727                 if (nop == 0)
 728                         return htonl(NFS4ERR_OP_NOT_IN_SESSION);
 729         }
 730
 731         switch (op_nr) {
 732         case OP_CB_GETATTR:
 733         case OP_CB_RECALL:
 734         case OP_CB_SEQUENCE:
 735         case OP_CB_RECALL_ANY:
 736         case OP_CB_RECALL_SLOT:
 737         case OP_CB_LAYOUTRECALL:
 738         case OP_CB_NOTIFY_DEVICEID:
 739                 *op = &callback_ops[op_nr];
 740                 break;
 741
 742         case OP_CB_NOTIFY:
 743         case OP_CB_PUSH_DELEG:
 744         case OP_CB_RECALLABLE_OBJ_AVAIL:
 745         case OP_CB_WANTS_CANCELLED:
 746         case OP_CB_NOTIFY_LOCK:
 747                 return htonl(NFS4ERR_NOTSUPP);
 748
 749         default:
 750                 return htonl(NFS4ERR_OP_ILLEGAL);
 751         }
 752
 753         return htonl(NFS_OK);
 754 }
 755
 756 static void nfs4_callback_free_slot(struct nfs4_session *session)
 757 {
 758         struct nfs4_slot_table *tbl = &session->bc_slot_table;
 759
 760         spin_lock(&tbl->slot_tbl_lock);
 761         /*
 762          * Let the state manager know callback processing done.
 763          * A single slot, so highest used slotid is either 0 or -1
 764          */
 765         tbl->highest_used_slotid = NFS4_NO_SLOT;
 766         nfs4_slot_tbl_drain_complete(tbl);
 767         spin_unlock(&tbl->slot_tbl_lock);
 768 }
 769
 770 static void nfs4_cb_free_slot(struct cb_process_state *cps)
 771 {
 772         if (cps->slotid != NFS4_NO_SLOT)
 773                 nfs4_callback_free_slot(cps->clp->cl_session);
 774 }
 775
 776 #else /* CONFIG_NFS_V4_1 */
 777
 778 static __be32
 779 preprocess_nfs41_op(int nop, unsigned int op_nr, struct callback_op **op)
 780 {
 781         return htonl(NFS4ERR_MINOR_VERS_MISMATCH);
 782 }
 783
 784 static void nfs4_cb_free_slot(struct cb_process_state *cps)
 785 {
 786 }
 787 #endif /* CONFIG_NFS_V4_1 */
 788
 789 #ifdef CONFIG_NFS_V4_2
 790 static __be32
 791 preprocess_nfs42_op(int nop, unsigned int op_nr, struct callback_op **op)
 792 {
 793         __be32 status = preprocess_nfs41_op(nop, op_nr, op);
 794         if (status != htonl(NFS4ERR_OP_ILLEGAL))
 795                 return status;
 796
 797         if (op_nr == OP_CB_OFFLOAD)
 798                 return htonl(NFS4ERR_NOTSUPP);
 799         return htonl(NFS4ERR_OP_ILLEGAL);
 800 }
 801 #else /* CONFIG_NFS_V4_2 */
 802 static __be32
 803 preprocess_nfs42_op(int nop, unsigned int op_nr, struct callback_op **op)
 804 {
 805         return htonl(NFS4ERR_MINOR_VERS_MISMATCH);
 806 }
 807 #endif /* CONFIG_NFS_V4_2 */
 808
 809 static __be32
 810 preprocess_nfs4_op(unsigned int op_nr, struct callback_op **op)
 811 {
 812         switch (op_nr) {
 813         case OP_CB_GETATTR:
 814         case OP_CB_RECALL:
 815                 *op = &callback_ops[op_nr];
 816                 break;
 817         default:
 818                 return htonl(NFS4ERR_OP_ILLEGAL);
 819         }
 820
 821         return htonl(NFS_OK);
 822 }
 823
 824 static __be32 process_op(int nop, struct svc_rqst *rqstp,
 825                 struct xdr_stream *xdr_in, void *argp,
 826                 struct xdr_stream *xdr_out, void *resp,
 827                 struct cb_process_state *cps)
 828 {
 829         struct callback_op *op = &callback_ops[0];
 830         unsigned int op_nr;
 831         __be32 status;
 832         long maxlen;
 833         __be32 res;
 834
 835         dprintk("%s: start\n", __func__);
 836         status = decode_op_hdr(xdr_in, &op_nr);
 837         if (unlikely(status))
 838                 return status;
 839
 840         dprintk("%s: minorversion=%d nop=%d op_nr=%u\n",
 841                 __func__, cps->minorversion, nop, op_nr);
 842
 843         switch (cps->minorversion) {
 844         case 0:
 845                 status = preprocess_nfs4_op(op_nr, &op);
 846                 break;
 847         case 1:
 848                 status = preprocess_nfs41_op(nop, op_nr, &op);
 849                 break;
 850         case 2:
 851                 status = preprocess_nfs42_op(nop, op_nr, &op);
 852                 break;
 853         default:
 854                 status = htonl(NFS4ERR_MINOR_VERS_MISMATCH);
 855         }
 856
 857         if (status == htonl(NFS4ERR_OP_ILLEGAL))
 858                 op_nr = OP_CB_ILLEGAL;
 859         if (status)
 860                 goto encode_hdr;
 861
 862         if (cps->drc_status) {
 863                 status = cps->drc_status;
 864                 goto encode_hdr;
 865         }
 866
 867         maxlen = xdr_out->end - xdr_out->p;
 868         if (maxlen > 0 && maxlen < PAGE_SIZE) {
 869                 status = op->decode_args(rqstp, xdr_in, argp);
 870                 if (likely(status == 0))
 871                         status = op->process_op(argp, resp, cps);
 872         } else
 873                 status = htonl(NFS4ERR_RESOURCE);
 874
 875 encode_hdr:
 876         res = encode_op_hdr(xdr_out, op_nr, status);
 877         if (unlikely(res))
 878                 return res;
 879         if (op->encode_res != NULL && status == 0)
 880                 status = op->encode_res(rqstp, xdr_out, resp);
 881         dprintk("%s: done, status = %d\n", __func__, ntohl(status));
 882         return status;
 883 }
 884
 885 /*
 886  * Decode, process and encode a COMPOUND
 887  */
 888 static __be32 nfs4_callback_compound(struct svc_rqst *rqstp, void *argp, void *resp)
 889 {
 890         struct cb_compound_hdr_arg hdr_arg = { 0 };
 891         struct cb_compound_hdr_res hdr_res = { NULL };
 892         struct xdr_stream xdr_in, xdr_out;
 893         struct xdr_buf *rq_arg = &rqstp->rq_arg;
 894         __be32 *p, status;
 895         struct cb_process_state cps = {
 896                 .drc_status = 0,
 897                 .clp = NULL,
 898                 .slotid = NFS4_NO_SLOT,
 899                 .net = SVC_NET(rqstp),
 900         };
 901         unsigned int nops = 0;
 902
 903         dprintk("%s: start\n", __func__);
 904
 905         rq_arg->len = rq_arg->head[0].iov_len + rq_arg->page_len;
 906         xdr_init_decode(&xdr_in, rq_arg, rq_arg->head[0].iov_base);
 907
 908         p = (__be32*)((char *)rqstp->rq_res.head[0].iov_base + rqstp->rq_res.head[0].iov_len);
 909         xdr_init_encode(&xdr_out, &rqstp->rq_res, p);
 910
 911         status = decode_compound_hdr_arg(&xdr_in, &hdr_arg);
 912         if (status == htonl(NFS4ERR_RESOURCE))
 913                 return rpc_garbage_args;
 914
 915         if (hdr_arg.minorversion == 0) {
 916                 cps.clp = nfs4_find_client_ident(SVC_NET(rqstp), hdr_arg.cb_ident);
 917                 if (!cps.clp || !check_gss_callback_principal(cps.clp, rqstp))
 918                         return rpc_drop_reply;
 919         }
 920
 921         cps.minorversion = hdr_arg.minorversion;
 922         hdr_res.taglen = hdr_arg.taglen;
 923         hdr_res.tag = hdr_arg.tag;
 924         if (encode_compound_hdr_res(&xdr_out, &hdr_res) != 0)
 925                 return rpc_system_err;
 926
 927         while (status == 0 && nops != hdr_arg.nops) {
 928                 status = process_op(nops, rqstp, &xdr_in,
 929                                     argp, &xdr_out, resp, &cps);
 930                 nops++;
 931         }
 932
 933         /* Buffer overflow in decode_ops_hdr or encode_ops_hdr. Return
 934         * resource error in cb_compound status without returning op */
 935         if (unlikely(status == htonl(NFS4ERR_RESOURCE_HDR))) {
 936                 status = htonl(NFS4ERR_RESOURCE);
 937                 nops--;
 938         }
 939
 940         *hdr_res.status = status;
 941         *hdr_res.nops = htonl(nops);
 942         nfs4_cb_free_slot(&cps);
 943         nfs_put_client(cps.clp);
 944         dprintk("%s: done, status = %u\n", __func__, ntohl(status));
 945         return rpc_success;
 946 }
 947
 948 /*
 949  * Define NFS4 callback COMPOUND ops.
 950  */
 951 static struct callback_op callback_ops[] = {
 952         [0] = {
 953                 .res_maxsize = CB_OP_HDR_RES_MAXSZ,
 954         },
 955         [OP_CB_GETATTR] = {
 956                 .process_op = (callback_process_op_t)nfs4_callback_getattr,
 957                 .decode_args = (callback_decode_arg_t)decode_getattr_args,
 958                 .encode_res = (callback_encode_res_t)encode_getattr_res,
 959                 .res_maxsize = CB_OP_GETATTR_RES_MAXSZ,
 960         },
 961         [OP_CB_RECALL] = {
 962                 .process_op = (callback_process_op_t)nfs4_callback_recall,
 963                 .decode_args = (callback_decode_arg_t)decode_recall_args,
 964                 .res_maxsize = CB_OP_RECALL_RES_MAXSZ,
 965         },
 966 #if defined(CONFIG_NFS_V4_1)
 967         [OP_CB_LAYOUTRECALL] = {
 968                 .process_op = (callback_process_op_t)nfs4_callback_layoutrecall,
 969                 .decode_args =
 970                         (callback_decode_arg_t)decode_layoutrecall_args,
 971                 .res_maxsize = CB_OP_LAYOUTRECALL_RES_MAXSZ,
 972         },
 973         [OP_CB_NOTIFY_DEVICEID] = {
 974                 .process_op = (callback_process_op_t)nfs4_callback_devicenotify,
 975                 .decode_args =
 976                         (callback_decode_arg_t)decode_devicenotify_args,
 977                 .res_maxsize = CB_OP_DEVICENOTIFY_RES_MAXSZ,
 978         },
 979         [OP_CB_SEQUENCE] = {
 980                 .process_op = (callback_process_op_t)nfs4_callback_sequence,
 981                 .decode_args = (callback_decode_arg_t)decode_cb_sequence_args,
 982                 .encode_res = (callback_encode_res_t)encode_cb_sequence_res,
 983                 .res_maxsize = CB_OP_SEQUENCE_RES_MAXSZ,
 984         },
 985         [OP_CB_RECALL_ANY] = {
 986                 .process_op = (callback_process_op_t)nfs4_callback_recallany,
 987                 .decode_args = (callback_decode_arg_t)decode_recallany_args,
 988                 .res_maxsize = CB_OP_RECALLANY_RES_MAXSZ,
 989         },
 990         [OP_CB_RECALL_SLOT] = {
 991                 .process_op = (callback_process_op_t)nfs4_callback_recallslot,
 992                 .decode_args = (callback_decode_arg_t)decode_recallslot_args,
 993                 .res_maxsize = CB_OP_RECALLSLOT_RES_MAXSZ,
 994         },
 995 #endif /* CONFIG_NFS_V4_1 */
 996 };
 997
 998 /*
 999  * Define NFS4 callback procedures
1000  */
1001 static struct svc_procedure nfs4_callback_procedures1[] = {
1002         [CB_NULL] = {
1003                 .pc_func = nfs4_callback_null,
1004                 .pc_decode = (kxdrproc_t)nfs4_decode_void,
1005                 .pc_encode = (kxdrproc_t)nfs4_encode_void,
1006                 .pc_xdrressize = 1,
1007         },
1008         [CB_COMPOUND] = {
1009                 .pc_func = nfs4_callback_compound,
1010                 .pc_encode = (kxdrproc_t)nfs4_encode_void,
1011                 .pc_argsize = 256,
1012                 .pc_ressize = 256,
1013                 .pc_xdrressize = NFS4_CALLBACK_BUFSIZE,
1014         }
1015 };
1016
1017 struct svc_version nfs4_callback_version1 = {
1018         .vs_vers = 1,
1019         .vs_nproc = ARRAY_SIZE(nfs4_callback_procedures1),
1020         .vs_proc = nfs4_callback_procedures1,
1021         .vs_xdrsize = NFS4_CALLBACK_XDRSIZE,
1022         .vs_dispatch = NULL,
1023         .vs_hidden = 1,
1024 };
1025
1026 struct svc_version nfs4_callback_version4 = {
1027         .vs_vers = 4,
1028         .vs_nproc = ARRAY_SIZE(nfs4_callback_procedures1),
1029         .vs_proc = nfs4_callback_procedures1,
1030         .vs_xdrsize = NFS4_CALLBACK_XDRSIZE,
1031         .vs_dispatch = NULL,
1032         .vs_hidden = 1,
1033 };