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/slab.h>
  13 #include <linux/sunrpc/bc_xprt.h>
  14 #include "nfs4_fs.h"
  15 #include "callback.h"
  16 #include "internal.h"
  17
  18 #define CB_OP_TAGLEN_MAXSZ      (512)
  19 #define CB_OP_HDR_RES_MAXSZ     (2 + CB_OP_TAGLEN_MAXSZ)
  20 #define CB_OP_GETATTR_BITMAP_MAXSZ      (4)
  21 #define CB_OP_GETATTR_RES_MAXSZ (CB_OP_HDR_RES_MAXSZ + \
  22                                 CB_OP_GETATTR_BITMAP_MAXSZ + \
  23                                 2 + 2 + 3 + 3)
  24 #define CB_OP_RECALL_RES_MAXSZ  (CB_OP_HDR_RES_MAXSZ)
  25
  26 #if defined(CONFIG_NFS_V4_1)
  27 #define CB_OP_LAYOUTRECALL_RES_MAXSZ    (CB_OP_HDR_RES_MAXSZ)
  28 #define CB_OP_DEVICENOTIFY_RES_MAXSZ    (CB_OP_HDR_RES_MAXSZ)
  29 #define CB_OP_SEQUENCE_RES_MAXSZ        (CB_OP_HDR_RES_MAXSZ + \
  30                                         4 + 1 + 3)
  31 #define CB_OP_RECALLANY_RES_MAXSZ       (CB_OP_HDR_RES_MAXSZ)
  32 #define CB_OP_RECALLSLOT_RES_MAXSZ      (CB_OP_HDR_RES_MAXSZ)
  33 #endif /* CONFIG_NFS_V4_1 */
  34
  35 #define NFSDBG_FACILITY NFSDBG_CALLBACK
  36
  37 /* Internal error code */
  38 #define NFS4ERR_RESOURCE_HDR    11050
  39
  40 typedef __be32 (*callback_process_op_t)(void *, void *,
  41                                         struct cb_process_state *);
  42 typedef __be32 (*callback_decode_arg_t)(struct svc_rqst *, struct xdr_stream *, void *);
  43 typedef __be32 (*callback_encode_res_t)(struct svc_rqst *, struct xdr_stream *, void *);
  44
  45
  46 struct callback_op {
  47         callback_process_op_t process_op;
  48         callback_decode_arg_t decode_args;
  49         callback_encode_res_t encode_res;
  50         long res_maxsize;
  51 };
  52
  53 static struct callback_op callback_ops[];
  54
  55 static __be32 nfs4_callback_null(struct svc_rqst *rqstp, void *argp, void *resp)
  56 {
  57         return htonl(NFS4_OK);
  58 }
  59
  60 static int nfs4_decode_void(struct svc_rqst *rqstp, __be32 *p, void *dummy)
  61 {
  62         return xdr_argsize_check(rqstp, p);
  63 }
  64
  65 static int nfs4_encode_void(struct svc_rqst *rqstp, __be32 *p, void *dummy)
  66 {
  67         return xdr_ressize_check(rqstp, p);
  68 }
  69
  70 static __be32 *read_buf(struct xdr_stream *xdr, int nbytes)
  71 {
  72         __be32 *p;
  73
  74         p = xdr_inline_decode(xdr, nbytes);
  75         if (unlikely(p == NULL))
  76                 printk(KERN_WARNING "NFSv4 callback reply buffer overflowed!\n");
  77         return p;
  78 }
  79
  80 static __be32 decode_string(struct xdr_stream *xdr, unsigned int *len, const char **str)
  81 {
  82         __be32 *p;
  83
  84         p = read_buf(xdr, 4);
  85         if (unlikely(p == NULL))
  86                 return htonl(NFS4ERR_RESOURCE);
  87         *len = ntohl(*p);
  88
  89         if (*len != 0) {
  90                 p = read_buf(xdr, *len);
  91                 if (unlikely(p == NULL))
  92                         return htonl(NFS4ERR_RESOURCE);
  93                 *str = (const char *)p;
  94         } else
  95                 *str = NULL;
  96
  97         return 0;
  98 }
  99
 100 static __be32 decode_fh(struct xdr_stream *xdr, struct nfs_fh *fh)
 101 {
 102         __be32 *p;
 103
 104         p = read_buf(xdr, 4);
 105         if (unlikely(p == NULL))
 106                 return htonl(NFS4ERR_RESOURCE);
 107         fh->size = ntohl(*p);
 108         if (fh->size > NFS4_FHSIZE)
 109                 return htonl(NFS4ERR_BADHANDLE);
 110         p = read_buf(xdr, fh->size);
 111         if (unlikely(p == NULL))
 112                 return htonl(NFS4ERR_RESOURCE);
 113         memcpy(&fh->data[0], p, fh->size);
 114         memset(&fh->data[fh->size], 0, sizeof(fh->data) - fh->size);
 115         return 0;
 116 }
 117
 118 static __be32 decode_bitmap(struct xdr_stream *xdr, uint32_t *bitmap)
 119 {
 120         __be32 *p;
 121         unsigned int attrlen;
 122
 123         p = read_buf(xdr, 4);
 124         if (unlikely(p == NULL))
 125                 return htonl(NFS4ERR_RESOURCE);
 126         attrlen = ntohl(*p);
 127         p = read_buf(xdr, attrlen << 2);
 128         if (unlikely(p == NULL))
 129                 return htonl(NFS4ERR_RESOURCE);
 130         if (likely(attrlen > 0))
 131                 bitmap[0] = ntohl(*p++);
 132         if (attrlen > 1)
 133                 bitmap[1] = ntohl(*p);
 134         return 0;
 135 }
 136
 137 static __be32 decode_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
 138 {
 139         __be32 *p;
 140
 141         p = read_buf(xdr, 16);
 142         if (unlikely(p == NULL))
 143                 return htonl(NFS4ERR_RESOURCE);
 144         memcpy(stateid->data, p, 16);
 145         return 0;
 146 }
 147
 148 static __be32 decode_compound_hdr_arg(struct xdr_stream *xdr, struct cb_compound_hdr_arg *hdr)
 149 {
 150         __be32 *p;
 151         __be32 status;
 152
 153         status = decode_string(xdr, &hdr->taglen, &hdr->tag);
 154         if (unlikely(status != 0))
 155                 return status;
 156         /* We do not like overly long tags! */
 157         if (hdr->taglen > CB_OP_TAGLEN_MAXSZ - 12) {
 158                 printk("NFSv4 CALLBACK %s: client sent tag of length %u\n",
 159                                 __func__, hdr->taglen);
 160                 return htonl(NFS4ERR_RESOURCE);
 161         }
 162         p = read_buf(xdr, 12);
 163         if (unlikely(p == NULL))
 164                 return htonl(NFS4ERR_RESOURCE);
 165         hdr->minorversion = ntohl(*p++);
 166         /* Check minor version is zero or one. */
 167         if (hdr->minorversion <= 1) {
 168                 hdr->cb_ident = ntohl(*p++); /* ignored by v4.1 */
 169         } else {
 170                 printk(KERN_WARNING "%s: NFSv4 server callback with "
 171                         "illegal minor version %u!\n",
 172                         __func__, hdr->minorversion);
 173                 return htonl(NFS4ERR_MINOR_VERS_MISMATCH);
 174         }
 175         hdr->nops = ntohl(*p);
 176         dprintk("%s: minorversion %d nops %d\n", __func__,
 177                 hdr->minorversion, hdr->nops);
 178         return 0;
 179 }
 180
 181 static __be32 decode_op_hdr(struct xdr_stream *xdr, unsigned int *op)
 182 {
 183         __be32 *p;
 184         p = read_buf(xdr, 4);
 185         if (unlikely(p == NULL))
 186                 return htonl(NFS4ERR_RESOURCE_HDR);
 187         *op = ntohl(*p);
 188         return 0;
 189 }
 190
 191 static __be32 decode_getattr_args(struct svc_rqst *rqstp, struct xdr_stream *xdr, struct cb_getattrargs *args)
 192 {
 193         __be32 status;
 194
 195         status = decode_fh(xdr, &args->fh);
 196         if (unlikely(status != 0))
 197                 goto out;
 198         args->addr = svc_addr(rqstp);
 199         status = decode_bitmap(xdr, args->bitmap);
 200 out:
 201         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 202         return status;
 203 }
 204
 205 static __be32 decode_recall_args(struct svc_rqst *rqstp, struct xdr_stream *xdr, struct cb_recallargs *args)
 206 {
 207         __be32 *p;
 208         __be32 status;
 209
 210         args->addr = svc_addr(rqstp);
 211         status = decode_stateid(xdr, &args->stateid);
 212         if (unlikely(status != 0))
 213                 goto out;
 214         p = read_buf(xdr, 4);
 215         if (unlikely(p == NULL)) {
 216                 status = htonl(NFS4ERR_RESOURCE);
 217                 goto out;
 218         }
 219         args->truncate = ntohl(*p);
 220         status = decode_fh(xdr, &args->fh);
 221 out:
 222         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 223         return status;
 224 }
 225
 226 #if defined(CONFIG_NFS_V4_1)
 227
 228 static __be32 decode_layoutrecall_args(struct svc_rqst *rqstp,
 229                                        struct xdr_stream *xdr,
 230                                        struct cb_layoutrecallargs *args)
 231 {
 232         __be32 *p;
 233         __be32 status = 0;
 234         uint32_t iomode;
 235
 236         args->cbl_addr = svc_addr(rqstp);
 237         p = read_buf(xdr, 4 * sizeof(uint32_t));
 238         if (unlikely(p == NULL)) {
 239                 status = htonl(NFS4ERR_BADXDR);
 240                 goto out;
 241         }
 242
 243         args->cbl_layout_type = ntohl(*p++);
 244         /* Depite the spec's xdr, iomode really belongs in the FILE switch,
 245          * as it is unusable and ignored with the other types.
 246          */
 247         iomode = ntohl(*p++);
 248         args->cbl_layoutchanged = ntohl(*p++);
 249         args->cbl_recall_type = ntohl(*p++);
 250
 251         if (args->cbl_recall_type == RETURN_FILE) {
 252                 args->cbl_range.iomode = iomode;
 253                 status = decode_fh(xdr, &args->cbl_fh);
 254                 if (unlikely(status != 0))
 255                         goto out;
 256
 257                 p = read_buf(xdr, 2 * sizeof(uint64_t));
 258                 if (unlikely(p == NULL)) {
 259                         status = htonl(NFS4ERR_BADXDR);
 260                         goto out;
 261                 }
 262                 p = xdr_decode_hyper(p, &args->cbl_range.offset);
 263                 p = xdr_decode_hyper(p, &args->cbl_range.length);
 264                 status = decode_stateid(xdr, &args->cbl_stateid);
 265                 if (unlikely(status != 0))
 266                         goto out;
 267         } else if (args->cbl_recall_type == RETURN_FSID) {
 268                 p = read_buf(xdr, 2 * sizeof(uint64_t));
 269                 if (unlikely(p == NULL)) {
 270                         status = htonl(NFS4ERR_BADXDR);
 271                         goto out;
 272                 }
 273                 p = xdr_decode_hyper(p, &args->cbl_fsid.major);
 274                 p = xdr_decode_hyper(p, &args->cbl_fsid.minor);
 275         } else if (args->cbl_recall_type != RETURN_ALL) {
 276                 status = htonl(NFS4ERR_BADXDR);
 277                 goto out;
 278         }
 279         dprintk("%s: ltype 0x%x iomode %d changed %d recall_type %d\n",
 280                 __func__,
 281                 args->cbl_layout_type, iomode,
 282                 args->cbl_layoutchanged, args->cbl_recall_type);
 283 out:
 284         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 285         return status;
 286 }
 287
 288 static
 289 __be32 decode_devicenotify_args(struct svc_rqst *rqstp,
 290                                 struct xdr_stream *xdr,
 291                                 struct cb_devicenotifyargs *args)
 292 {
 293         __be32 *p;
 294         __be32 status = 0;
 295         u32 tmp;
 296         int n, i;
 297         args->ndevs = 0;
 298
 299         /* Num of device notifications */
 300         p = read_buf(xdr, sizeof(uint32_t));
 301         if (unlikely(p == NULL)) {
 302                 status = htonl(NFS4ERR_BADXDR);
 303                 goto out;
 304         }
 305         n = ntohl(*p++);
 306         if (n <= 0)
 307                 goto out;
 308         if (n > ULONG_MAX / sizeof(*args->devs)) {
 309                 status = htonl(NFS4ERR_BADXDR);
 310                 goto out;
 311         }
 312
 313         args->devs = kmalloc(n * sizeof(*args->devs), GFP_KERNEL);
 314         if (!args->devs) {
 315                 status = htonl(NFS4ERR_DELAY);
 316                 goto out;
 317         }
 318
 319         /* Decode each dev notification */
 320         for (i = 0; i < n; i++) {
 321                 struct cb_devicenotifyitem *dev = &args->devs[i];
 322
 323                 p = read_buf(xdr, (4 * sizeof(uint32_t)) + NFS4_DEVICEID4_SIZE);
 324                 if (unlikely(p == NULL)) {
 325                         status = htonl(NFS4ERR_BADXDR);
 326                         goto err;
 327                 }
 328
 329                 tmp = ntohl(*p++);      /* bitmap size */
 330                 if (tmp != 1) {
 331                         status = htonl(NFS4ERR_INVAL);
 332                         goto err;
 333                 }
 334                 dev->cbd_notify_type = ntohl(*p++);
 335                 if (dev->cbd_notify_type != NOTIFY_DEVICEID4_CHANGE &&
 336                     dev->cbd_notify_type != NOTIFY_DEVICEID4_DELETE) {
 337                         status = htonl(NFS4ERR_INVAL);
 338                         goto err;
 339                 }
 340
 341                 tmp = ntohl(*p++);      /* opaque size */
 342                 if (((dev->cbd_notify_type == NOTIFY_DEVICEID4_CHANGE) &&
 343                      (tmp != NFS4_DEVICEID4_SIZE + 8)) ||
 344                     ((dev->cbd_notify_type == NOTIFY_DEVICEID4_DELETE) &&
 345                      (tmp != NFS4_DEVICEID4_SIZE + 4))) {
 346                         status = htonl(NFS4ERR_INVAL);
 347                         goto err;
 348                 }
 349                 dev->cbd_layout_type = ntohl(*p++);
 350                 memcpy(dev->cbd_dev_id.data, p, NFS4_DEVICEID4_SIZE);
 351                 p += XDR_QUADLEN(NFS4_DEVICEID4_SIZE);
 352
 353                 if (dev->cbd_layout_type == NOTIFY_DEVICEID4_CHANGE) {
 354                         p = read_buf(xdr, sizeof(uint32_t));
 355                         if (unlikely(p == NULL)) {
 356                                 status = htonl(NFS4ERR_BADXDR);
 357                                 goto err;
 358                         }
 359                         dev->cbd_immediate = ntohl(*p++);
 360                 } else {
 361                         dev->cbd_immediate = 0;
 362                 }
 363
 364                 args->ndevs++;
 365
 366                 dprintk("%s: type %d layout 0x%x immediate %d\n",
 367                         __func__, dev->cbd_notify_type, dev->cbd_layout_type,
 368                         dev->cbd_immediate);
 369         }
 370 out:
 371         dprintk("%s: status %d ndevs %d\n",
 372                 __func__, ntohl(status), args->ndevs);
 373         return status;
 374 err:
 375         kfree(args->devs);
 376         goto out;
 377 }
 378
 379 static __be32 decode_sessionid(struct xdr_stream *xdr,
 380                                  struct nfs4_sessionid *sid)
 381 {
 382         __be32 *p;
 383         int len = NFS4_MAX_SESSIONID_LEN;
 384
 385         p = read_buf(xdr, len);
 386         if (unlikely(p == NULL))
 387                 return htonl(NFS4ERR_RESOURCE);
 388
 389         memcpy(sid->data, p, len);
 390         return 0;
 391 }
 392
 393 static __be32 decode_rc_list(struct xdr_stream *xdr,
 394                                struct referring_call_list *rc_list)
 395 {
 396         __be32 *p;
 397         int i;
 398         __be32 status;
 399
 400         status = decode_sessionid(xdr, &rc_list->rcl_sessionid);
 401         if (status)
 402                 goto out;
 403
 404         status = htonl(NFS4ERR_RESOURCE);
 405         p = read_buf(xdr, sizeof(uint32_t));
 406         if (unlikely(p == NULL))
 407                 goto out;
 408
 409         rc_list->rcl_nrefcalls = ntohl(*p++);
 410         if (rc_list->rcl_nrefcalls) {
 411                 p = read_buf(xdr,
 412                              rc_list->rcl_nrefcalls * 2 * sizeof(uint32_t));
 413                 if (unlikely(p == NULL))
 414                         goto out;
 415                 rc_list->rcl_refcalls = kmalloc(rc_list->rcl_nrefcalls *
 416                                                 sizeof(*rc_list->rcl_refcalls),
 417                                                 GFP_KERNEL);
 418                 if (unlikely(rc_list->rcl_refcalls == NULL))
 419                         goto out;
 420                 for (i = 0; i < rc_list->rcl_nrefcalls; i++) {
 421                         rc_list->rcl_refcalls[i].rc_sequenceid = ntohl(*p++);
 422                         rc_list->rcl_refcalls[i].rc_slotid = ntohl(*p++);
 423                 }
 424         }
 425         status = 0;
 426
 427 out:
 428         return status;
 429 }
 430
 431 static __be32 decode_cb_sequence_args(struct svc_rqst *rqstp,
 432                                         struct xdr_stream *xdr,
 433                                         struct cb_sequenceargs *args)
 434 {
 435         __be32 *p;
 436         int i;
 437         __be32 status;
 438
 439         status = decode_sessionid(xdr, &args->csa_sessionid);
 440         if (status)
 441                 goto out;
 442
 443         status = htonl(NFS4ERR_RESOURCE);
 444         p = read_buf(xdr, 5 * sizeof(uint32_t));
 445         if (unlikely(p == NULL))
 446                 goto out;
 447
 448         args->csa_addr = svc_addr(rqstp);
 449         args->csa_sequenceid = ntohl(*p++);
 450         args->csa_slotid = ntohl(*p++);
 451         args->csa_highestslotid = ntohl(*p++);
 452         args->csa_cachethis = ntohl(*p++);
 453         args->csa_nrclists = ntohl(*p++);
 454         args->csa_rclists = NULL;
 455         if (args->csa_nrclists) {
 456                 args->csa_rclists = kmalloc(args->csa_nrclists *
 457                                             sizeof(*args->csa_rclists),
 458                                             GFP_KERNEL);
 459                 if (unlikely(args->csa_rclists == NULL))
 460                         goto out;
 461
 462                 for (i = 0; i < args->csa_nrclists; i++) {
 463                         status = decode_rc_list(xdr, &args->csa_rclists[i]);
 464                         if (status)
 465                                 goto out_free;
 466                 }
 467         }
 468         status = 0;
 469
 470         dprintk("%s: sessionid %x:%x:%x:%x sequenceid %u slotid %u "
 471                 "highestslotid %u cachethis %d nrclists %u\n",
 472                 __func__,
 473                 ((u32 *)&args->csa_sessionid)[0],
 474                 ((u32 *)&args->csa_sessionid)[1],
 475                 ((u32 *)&args->csa_sessionid)[2],
 476                 ((u32 *)&args->csa_sessionid)[3],
 477                 args->csa_sequenceid, args->csa_slotid,
 478                 args->csa_highestslotid, args->csa_cachethis,
 479                 args->csa_nrclists);
 480 out:
 481         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 482         return status;
 483
 484 out_free:
 485         for (i = 0; i < args->csa_nrclists; i++)
 486                 kfree(args->csa_rclists[i].rcl_refcalls);
 487         kfree(args->csa_rclists);
 488         goto out;
 489 }
 490
 491 static __be32 decode_recallany_args(struct svc_rqst *rqstp,
 492                                       struct xdr_stream *xdr,
 493                                       struct cb_recallanyargs *args)
 494 {
 495         uint32_t bitmap[2];
 496         __be32 *p, status;
 497
 498         args->craa_addr = svc_addr(rqstp);
 499         p = read_buf(xdr, 4);
 500         if (unlikely(p == NULL))
 501                 return htonl(NFS4ERR_BADXDR);
 502         args->craa_objs_to_keep = ntohl(*p++);
 503         status = decode_bitmap(xdr, bitmap);
 504         if (unlikely(status))
 505                 return status;
 506         args->craa_type_mask = bitmap[0];
 507
 508         return 0;
 509 }
 510
 511 static __be32 decode_recallslot_args(struct svc_rqst *rqstp,
 512                                         struct xdr_stream *xdr,
 513                                         struct cb_recallslotargs *args)
 514 {
 515         __be32 *p;
 516
 517         args->crsa_addr = svc_addr(rqstp);
 518         p = read_buf(xdr, 4);
 519         if (unlikely(p == NULL))
 520                 return htonl(NFS4ERR_BADXDR);
 521         args->crsa_target_max_slots = ntohl(*p++);
 522         return 0;
 523 }
 524
 525 #endif /* CONFIG_NFS_V4_1 */
 526
 527 static __be32 encode_string(struct xdr_stream *xdr, unsigned int len, const char *str)
 528 {
 529         __be32 *p;
 530
 531         p = xdr_reserve_space(xdr, 4 + len);
 532         if (unlikely(p == NULL))
 533                 return htonl(NFS4ERR_RESOURCE);
 534         xdr_encode_opaque(p, str, len);
 535         return 0;
 536 }
 537
 538 #define CB_SUPPORTED_ATTR0 (FATTR4_WORD0_CHANGE|FATTR4_WORD0_SIZE)
 539 #define CB_SUPPORTED_ATTR1 (FATTR4_WORD1_TIME_METADATA|FATTR4_WORD1_TIME_MODIFY)
 540 static __be32 encode_attr_bitmap(struct xdr_stream *xdr, const uint32_t *bitmap, __be32 **savep)
 541 {
 542         __be32 bm[2];
 543         __be32 *p;
 544
 545         bm[0] = htonl(bitmap[0] & CB_SUPPORTED_ATTR0);
 546         bm[1] = htonl(bitmap[1] & CB_SUPPORTED_ATTR1);
 547         if (bm[1] != 0) {
 548                 p = xdr_reserve_space(xdr, 16);
 549                 if (unlikely(p == NULL))
 550                         return htonl(NFS4ERR_RESOURCE);
 551                 *p++ = htonl(2);
 552                 *p++ = bm[0];
 553                 *p++ = bm[1];
 554         } else if (bm[0] != 0) {
 555                 p = xdr_reserve_space(xdr, 12);
 556                 if (unlikely(p == NULL))
 557                         return htonl(NFS4ERR_RESOURCE);
 558                 *p++ = htonl(1);
 559                 *p++ = bm[0];
 560         } else {
 561                 p = xdr_reserve_space(xdr, 8);
 562                 if (unlikely(p == NULL))
 563                         return htonl(NFS4ERR_RESOURCE);
 564                 *p++ = htonl(0);
 565         }
 566         *savep = p;
 567         return 0;
 568 }
 569
 570 static __be32 encode_attr_change(struct xdr_stream *xdr, const uint32_t *bitmap, uint64_t change)
 571 {
 572         __be32 *p;
 573
 574         if (!(bitmap[0] & FATTR4_WORD0_CHANGE))
 575                 return 0;
 576         p = xdr_reserve_space(xdr, 8);
 577         if (unlikely(!p))
 578                 return htonl(NFS4ERR_RESOURCE);
 579         p = xdr_encode_hyper(p, change);
 580         return 0;
 581 }
 582
 583 static __be32 encode_attr_size(struct xdr_stream *xdr, const uint32_t *bitmap, uint64_t size)
 584 {
 585         __be32 *p;
 586
 587         if (!(bitmap[0] & FATTR4_WORD0_SIZE))
 588                 return 0;
 589         p = xdr_reserve_space(xdr, 8);
 590         if (unlikely(!p))
 591                 return htonl(NFS4ERR_RESOURCE);
 592         p = xdr_encode_hyper(p, size);
 593         return 0;
 594 }
 595
 596 static __be32 encode_attr_time(struct xdr_stream *xdr, const struct timespec *time)
 597 {
 598         __be32 *p;
 599
 600         p = xdr_reserve_space(xdr, 12);
 601         if (unlikely(!p))
 602                 return htonl(NFS4ERR_RESOURCE);
 603         p = xdr_encode_hyper(p, time->tv_sec);
 604         *p = htonl(time->tv_nsec);
 605         return 0;
 606 }
 607
 608 static __be32 encode_attr_ctime(struct xdr_stream *xdr, const uint32_t *bitmap, const struct timespec *time)
 609 {
 610         if (!(bitmap[1] & FATTR4_WORD1_TIME_METADATA))
 611                 return 0;
 612         return encode_attr_time(xdr,time);
 613 }
 614
 615 static __be32 encode_attr_mtime(struct xdr_stream *xdr, const uint32_t *bitmap, const struct timespec *time)
 616 {
 617         if (!(bitmap[1] & FATTR4_WORD1_TIME_MODIFY))
 618                 return 0;
 619         return encode_attr_time(xdr,time);
 620 }
 621
 622 static __be32 encode_compound_hdr_res(struct xdr_stream *xdr, struct cb_compound_hdr_res *hdr)
 623 {
 624         __be32 status;
 625
 626         hdr->status = xdr_reserve_space(xdr, 4);
 627         if (unlikely(hdr->status == NULL))
 628                 return htonl(NFS4ERR_RESOURCE);
 629         status = encode_string(xdr, hdr->taglen, hdr->tag);
 630         if (unlikely(status != 0))
 631                 return status;
 632         hdr->nops = xdr_reserve_space(xdr, 4);
 633         if (unlikely(hdr->nops == NULL))
 634                 return htonl(NFS4ERR_RESOURCE);
 635         return 0;
 636 }
 637
 638 static __be32 encode_op_hdr(struct xdr_stream *xdr, uint32_t op, __be32 res)
 639 {
 640         __be32 *p;
 641
 642         p = xdr_reserve_space(xdr, 8);
 643         if (unlikely(p == NULL))
 644                 return htonl(NFS4ERR_RESOURCE_HDR);
 645         *p++ = htonl(op);
 646         *p = res;
 647         return 0;
 648 }
 649
 650 static __be32 encode_getattr_res(struct svc_rqst *rqstp, struct xdr_stream *xdr, const struct cb_getattrres *res)
 651 {
 652         __be32 *savep = NULL;
 653         __be32 status = res->status;
 654
 655         if (unlikely(status != 0))
 656                 goto out;
 657         status = encode_attr_bitmap(xdr, res->bitmap, &savep);
 658         if (unlikely(status != 0))
 659                 goto out;
 660         status = encode_attr_change(xdr, res->bitmap, res->change_attr);
 661         if (unlikely(status != 0))
 662                 goto out;
 663         status = encode_attr_size(xdr, res->bitmap, res->size);
 664         if (unlikely(status != 0))
 665                 goto out;
 666         status = encode_attr_ctime(xdr, res->bitmap, &res->ctime);
 667         if (unlikely(status != 0))
 668                 goto out;
 669         status = encode_attr_mtime(xdr, res->bitmap, &res->mtime);
 670         *savep = htonl((unsigned int)((char *)xdr->p - (char *)(savep+1)));
 671 out:
 672         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 673         return status;
 674 }
 675
 676 #if defined(CONFIG_NFS_V4_1)
 677
 678 static __be32 encode_sessionid(struct xdr_stream *xdr,
 679                                  const struct nfs4_sessionid *sid)
 680 {
 681         __be32 *p;
 682         int len = NFS4_MAX_SESSIONID_LEN;
 683
 684         p = xdr_reserve_space(xdr, len);
 685         if (unlikely(p == NULL))
 686                 return htonl(NFS4ERR_RESOURCE);
 687
 688         memcpy(p, sid, len);
 689         return 0;
 690 }
 691
 692 static __be32 encode_cb_sequence_res(struct svc_rqst *rqstp,
 693                                        struct xdr_stream *xdr,
 694                                        const struct cb_sequenceres *res)
 695 {
 696         __be32 *p;
 697         unsigned status = res->csr_status;
 698
 699         if (unlikely(status != 0))
 700                 goto out;
 701
 702         encode_sessionid(xdr, &res->csr_sessionid);
 703
 704         p = xdr_reserve_space(xdr, 4 * sizeof(uint32_t));
 705         if (unlikely(p == NULL))
 706                 return htonl(NFS4ERR_RESOURCE);
 707
 708         *p++ = htonl(res->csr_sequenceid);
 709         *p++ = htonl(res->csr_slotid);
 710         *p++ = htonl(res->csr_highestslotid);
 711         *p++ = htonl(res->csr_target_highestslotid);
 712 out:
 713         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 714         return status;
 715 }
 716
 717 static __be32
 718 preprocess_nfs41_op(int nop, unsigned int op_nr, struct callback_op **op)
 719 {
 720         if (op_nr == OP_CB_SEQUENCE) {
 721                 if (nop != 0)
 722                         return htonl(NFS4ERR_SEQUENCE_POS);
 723         } else {
 724                 if (nop == 0)
 725                         return htonl(NFS4ERR_OP_NOT_IN_SESSION);
 726         }
 727
 728         switch (op_nr) {
 729         case OP_CB_GETATTR:
 730         case OP_CB_RECALL:
 731         case OP_CB_SEQUENCE:
 732         case OP_CB_RECALL_ANY:
 733         case OP_CB_RECALL_SLOT:
 734         case OP_CB_LAYOUTRECALL:
 735         case OP_CB_NOTIFY_DEVICEID:
 736                 *op = &callback_ops[op_nr];
 737                 break;
 738
 739         case OP_CB_NOTIFY:
 740         case OP_CB_PUSH_DELEG:
 741         case OP_CB_RECALLABLE_OBJ_AVAIL:
 742         case OP_CB_WANTS_CANCELLED:
 743         case OP_CB_NOTIFY_LOCK:
 744                 return htonl(NFS4ERR_NOTSUPP);
 745
 746         default:
 747                 return htonl(NFS4ERR_OP_ILLEGAL);
 748         }
 749
 750         return htonl(NFS_OK);
 751 }
 752
 753 static void nfs4_callback_free_slot(struct nfs4_session *session)
 754 {
 755         struct nfs4_slot_table *tbl = &session->bc_slot_table;
 756
 757         spin_lock(&tbl->slot_tbl_lock);
 758         /*
 759          * Let the state manager know callback processing done.
 760          * A single slot, so highest used slotid is either 0 or -1
 761          */
 762         tbl->highest_used_slotid = -1;
 763         nfs4_check_drain_bc_complete(session);
 764         spin_unlock(&tbl->slot_tbl_lock);
 765 }
 766
 767 static void nfs4_cb_free_slot(struct cb_process_state *cps)
 768 {
 769         if (cps->slotid != -1)
 770                 nfs4_callback_free_slot(cps->clp->cl_session);
 771 }
 772
 773 #else /* CONFIG_NFS_V4_1 */
 774
 775 static __be32
 776 preprocess_nfs41_op(int nop, unsigned int op_nr, struct callback_op **op)
 777 {
 778         return htonl(NFS4ERR_MINOR_VERS_MISMATCH);
 779 }
 780
 781 static void nfs4_cb_free_slot(struct cb_process_state *cps)
 782 {
 783 }
 784 #endif /* CONFIG_NFS_V4_1 */
 785
 786 static __be32
 787 preprocess_nfs4_op(unsigned int op_nr, struct callback_op **op)
 788 {
 789         switch (op_nr) {
 790         case OP_CB_GETATTR:
 791         case OP_CB_RECALL:
 792                 *op = &callback_ops[op_nr];
 793                 break;
 794         default:
 795                 return htonl(NFS4ERR_OP_ILLEGAL);
 796         }
 797
 798         return htonl(NFS_OK);
 799 }
 800
 801 static __be32 process_op(uint32_t minorversion, int nop,
 802                 struct svc_rqst *rqstp,
 803                 struct xdr_stream *xdr_in, void *argp,
 804                 struct xdr_stream *xdr_out, void *resp,
 805                 struct cb_process_state *cps)
 806 {
 807         struct callback_op *op = &callback_ops[0];
 808         unsigned int op_nr;
 809         __be32 status;
 810         long maxlen;
 811         __be32 res;
 812
 813         dprintk("%s: start\n", __func__);
 814         status = decode_op_hdr(xdr_in, &op_nr);
 815         if (unlikely(status))
 816                 return status;
 817
 818         dprintk("%s: minorversion=%d nop=%d op_nr=%u\n",
 819                 __func__, minorversion, nop, op_nr);
 820
 821         status = minorversion ? preprocess_nfs41_op(nop, op_nr, &op) :
 822                                 preprocess_nfs4_op(op_nr, &op);
 823         if (status == htonl(NFS4ERR_OP_ILLEGAL))
 824                 op_nr = OP_CB_ILLEGAL;
 825         if (status)
 826                 goto encode_hdr;
 827
 828         if (cps->drc_status) {
 829                 status = cps->drc_status;
 830                 goto encode_hdr;
 831         }
 832
 833         maxlen = xdr_out->end - xdr_out->p;
 834         if (maxlen > 0 && maxlen < PAGE_SIZE) {
 835                 status = op->decode_args(rqstp, xdr_in, argp);
 836                 if (likely(status == 0))
 837                         status = op->process_op(argp, resp, cps);
 838         } else
 839                 status = htonl(NFS4ERR_RESOURCE);
 840
 841 encode_hdr:
 842         res = encode_op_hdr(xdr_out, op_nr, status);
 843         if (unlikely(res))
 844                 return res;
 845         if (op->encode_res != NULL && status == 0)
 846                 status = op->encode_res(rqstp, xdr_out, resp);
 847         dprintk("%s: done, status = %d\n", __func__, ntohl(status));
 848         return status;
 849 }
 850
 851 /*
 852  * Decode, process and encode a COMPOUND
 853  */
 854 static __be32 nfs4_callback_compound(struct svc_rqst *rqstp, void *argp, void *resp)
 855 {
 856         struct cb_compound_hdr_arg hdr_arg = { 0 };
 857         struct cb_compound_hdr_res hdr_res = { NULL };
 858         struct xdr_stream xdr_in, xdr_out;
 859         __be32 *p, status;
 860         struct cb_process_state cps = {
 861                 .drc_status = 0,
 862                 .clp = NULL,
 863                 .slotid = -1,
 864         };
 865         unsigned int nops = 0;
 866
 867         dprintk("%s: start\n", __func__);
 868
 869         xdr_init_decode(&xdr_in, &rqstp->rq_arg, rqstp->rq_arg.head[0].iov_base);
 870
 871         p = (__be32*)((char *)rqstp->rq_res.head[0].iov_base + rqstp->rq_res.head[0].iov_len);
 872         xdr_init_encode(&xdr_out, &rqstp->rq_res, p);
 873
 874         status = decode_compound_hdr_arg(&xdr_in, &hdr_arg);
 875         if (status == __constant_htonl(NFS4ERR_RESOURCE))
 876                 return rpc_garbage_args;
 877
 878         if (hdr_arg.minorversion == 0) {
 879                 cps.clp = nfs4_find_client_ident(hdr_arg.cb_ident);
 880                 if (!cps.clp || !check_gss_callback_principal(cps.clp, rqstp))
 881                         return rpc_drop_reply;
 882         }
 883
 884         hdr_res.taglen = hdr_arg.taglen;
 885         hdr_res.tag = hdr_arg.tag;
 886         if (encode_compound_hdr_res(&xdr_out, &hdr_res) != 0)
 887                 return rpc_system_err;
 888
 889         while (status == 0 && nops != hdr_arg.nops) {
 890                 status = process_op(hdr_arg.minorversion, nops, rqstp,
 891                                     &xdr_in, argp, &xdr_out, resp, &cps);
 892                 nops++;
 893         }
 894
 895         /* Buffer overflow in decode_ops_hdr or encode_ops_hdr. Return
 896         * resource error in cb_compound status without returning op */
 897         if (unlikely(status == htonl(NFS4ERR_RESOURCE_HDR))) {
 898                 status = htonl(NFS4ERR_RESOURCE);
 899                 nops--;
 900         }
 901
 902         *hdr_res.status = status;
 903         *hdr_res.nops = htonl(nops);
 904         nfs4_cb_free_slot(&cps);
 905         nfs_put_client(cps.clp);
 906         dprintk("%s: done, status = %u\n", __func__, ntohl(status));
 907         return rpc_success;
 908 }
 909
 910 /*
 911  * Define NFS4 callback COMPOUND ops.
 912  */
 913 static struct callback_op callback_ops[] = {
 914         [0] = {
 915                 .res_maxsize = CB_OP_HDR_RES_MAXSZ,
 916         },
 917         [OP_CB_GETATTR] = {
 918                 .process_op = (callback_process_op_t)nfs4_callback_getattr,
 919                 .decode_args = (callback_decode_arg_t)decode_getattr_args,
 920                 .encode_res = (callback_encode_res_t)encode_getattr_res,
 921                 .res_maxsize = CB_OP_GETATTR_RES_MAXSZ,
 922         },
 923         [OP_CB_RECALL] = {
 924                 .process_op = (callback_process_op_t)nfs4_callback_recall,
 925                 .decode_args = (callback_decode_arg_t)decode_recall_args,
 926                 .res_maxsize = CB_OP_RECALL_RES_MAXSZ,
 927         },
 928 #if defined(CONFIG_NFS_V4_1)
 929         [OP_CB_LAYOUTRECALL] = {
 930                 .process_op = (callback_process_op_t)nfs4_callback_layoutrecall,
 931                 .decode_args =
 932                         (callback_decode_arg_t)decode_layoutrecall_args,
 933                 .res_maxsize = CB_OP_LAYOUTRECALL_RES_MAXSZ,
 934         },
 935         [OP_CB_NOTIFY_DEVICEID] = {
 936                 .process_op = (callback_process_op_t)nfs4_callback_devicenotify,
 937                 .decode_args =
 938                         (callback_decode_arg_t)decode_devicenotify_args,
 939                 .res_maxsize = CB_OP_DEVICENOTIFY_RES_MAXSZ,
 940         },
 941         [OP_CB_SEQUENCE] = {
 942                 .process_op = (callback_process_op_t)nfs4_callback_sequence,
 943                 .decode_args = (callback_decode_arg_t)decode_cb_sequence_args,
 944                 .encode_res = (callback_encode_res_t)encode_cb_sequence_res,
 945                 .res_maxsize = CB_OP_SEQUENCE_RES_MAXSZ,
 946         },
 947         [OP_CB_RECALL_ANY] = {
 948                 .process_op = (callback_process_op_t)nfs4_callback_recallany,
 949                 .decode_args = (callback_decode_arg_t)decode_recallany_args,
 950                 .res_maxsize = CB_OP_RECALLANY_RES_MAXSZ,
 951         },
 952         [OP_CB_RECALL_SLOT] = {
 953                 .process_op = (callback_process_op_t)nfs4_callback_recallslot,
 954                 .decode_args = (callback_decode_arg_t)decode_recallslot_args,
 955                 .res_maxsize = CB_OP_RECALLSLOT_RES_MAXSZ,
 956         },
 957 #endif /* CONFIG_NFS_V4_1 */
 958 };
 959
 960 /*
 961  * Define NFS4 callback procedures
 962  */
 963 static struct svc_procedure nfs4_callback_procedures1[] = {
 964         [CB_NULL] = {
 965                 .pc_func = nfs4_callback_null,
 966                 .pc_decode = (kxdrproc_t)nfs4_decode_void,
 967                 .pc_encode = (kxdrproc_t)nfs4_encode_void,
 968                 .pc_xdrressize = 1,
 969         },
 970         [CB_COMPOUND] = {
 971                 .pc_func = nfs4_callback_compound,
 972                 .pc_encode = (kxdrproc_t)nfs4_encode_void,
 973                 .pc_argsize = 256,
 974                 .pc_ressize = 256,
 975                 .pc_xdrressize = NFS4_CALLBACK_BUFSIZE,
 976         }
 977 };
 978
 979 struct svc_version nfs4_callback_version1 = {
 980         .vs_vers = 1,
 981         .vs_nproc = ARRAY_SIZE(nfs4_callback_procedures1),
 982         .vs_proc = nfs4_callback_procedures1,
 983         .vs_xdrsize = NFS4_CALLBACK_XDRSIZE,
 984         .vs_dispatch = NULL,
 985         .vs_hidden = 1,
 986 };
 987
 988 struct svc_version nfs4_callback_version4 = {
 989         .vs_vers = 4,
 990         .vs_nproc = ARRAY_SIZE(nfs4_callback_procedures1),
 991         .vs_proc = nfs4_callback_procedures1,
 992         .vs_xdrsize = NFS4_CALLBACK_XDRSIZE,
 993         .vs_dispatch = NULL,
 994         .vs_hidden = 1,
 995 };