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
  20 #define CB_OP_TAGLEN_MAXSZ      (512)
  21 #define CB_OP_HDR_RES_MAXSZ     (2 + CB_OP_TAGLEN_MAXSZ)
  22 #define CB_OP_GETATTR_BITMAP_MAXSZ      (4)
  23 #define CB_OP_GETATTR_RES_MAXSZ (CB_OP_HDR_RES_MAXSZ + \
  24                                 CB_OP_GETATTR_BITMAP_MAXSZ + \
  25                                 2 + 2 + 3 + 3)
  26 #define CB_OP_RECALL_RES_MAXSZ  (CB_OP_HDR_RES_MAXSZ)
  27
  28 #if defined(CONFIG_NFS_V4_1)
  29 #define CB_OP_LAYOUTRECALL_RES_MAXSZ    (CB_OP_HDR_RES_MAXSZ)
  30 #define CB_OP_DEVICENOTIFY_RES_MAXSZ    (CB_OP_HDR_RES_MAXSZ)
  31 #define CB_OP_SEQUENCE_RES_MAXSZ        (CB_OP_HDR_RES_MAXSZ + \
  32                                         4 + 1 + 3)
  33 #define CB_OP_RECALLANY_RES_MAXSZ       (CB_OP_HDR_RES_MAXSZ)
  34 #define CB_OP_RECALLSLOT_RES_MAXSZ      (CB_OP_HDR_RES_MAXSZ)
  35 #endif /* CONFIG_NFS_V4_1 */
  36
  37 #define NFSDBG_FACILITY NFSDBG_CALLBACK
  38
  39 /* Internal error code */
  40 #define NFS4ERR_RESOURCE_HDR    11050
  41
  42 typedef __be32 (*callback_process_op_t)(void *, void *,
  43                                         struct cb_process_state *);
  44 typedef __be32 (*callback_decode_arg_t)(struct svc_rqst *, struct xdr_stream *, void *);
  45 typedef __be32 (*callback_encode_res_t)(struct svc_rqst *, struct xdr_stream *, void *);
  46
  47
  48 struct callback_op {
  49         callback_process_op_t process_op;
  50         callback_decode_arg_t decode_args;
  51         callback_encode_res_t encode_res;
  52         long res_maxsize;
  53 };
  54
  55 static struct callback_op callback_ops[];
  56
  57 static __be32 nfs4_callback_null(struct svc_rqst *rqstp, void *argp, void *resp)
  58 {
  59         return htonl(NFS4_OK);
  60 }
  61
  62 static int nfs4_decode_void(struct svc_rqst *rqstp, __be32 *p, void *dummy)
  63 {
  64         return xdr_argsize_check(rqstp, p);
  65 }
  66
  67 static int nfs4_encode_void(struct svc_rqst *rqstp, __be32 *p, void *dummy)
  68 {
  69         return xdr_ressize_check(rqstp, p);
  70 }
  71
  72 static __be32 *read_buf(struct xdr_stream *xdr, int nbytes)
  73 {
  74         __be32 *p;
  75
  76         p = xdr_inline_decode(xdr, nbytes);
  77         if (unlikely(p == NULL))
  78                 printk(KERN_WARNING "NFS: NFSv4 callback reply buffer overflowed!\n");
  79         return p;
  80 }
  81
  82 static __be32 decode_string(struct xdr_stream *xdr, unsigned int *len, const char **str)
  83 {
  84         __be32 *p;
  85
  86         p = read_buf(xdr, 4);
  87         if (unlikely(p == NULL))
  88                 return htonl(NFS4ERR_RESOURCE);
  89         *len = ntohl(*p);
  90
  91         if (*len != 0) {
  92                 p = read_buf(xdr, *len);
  93                 if (unlikely(p == NULL))
  94                         return htonl(NFS4ERR_RESOURCE);
  95                 *str = (const char *)p;
  96         } else
  97                 *str = NULL;
  98
  99         return 0;
 100 }
 101
 102 static __be32 decode_fh(struct xdr_stream *xdr, struct nfs_fh *fh)
 103 {
 104         __be32 *p;
 105
 106         p = read_buf(xdr, 4);
 107         if (unlikely(p == NULL))
 108                 return htonl(NFS4ERR_RESOURCE);
 109         fh->size = ntohl(*p);
 110         if (fh->size > NFS4_FHSIZE)
 111                 return htonl(NFS4ERR_BADHANDLE);
 112         p = read_buf(xdr, fh->size);
 113         if (unlikely(p == NULL))
 114                 return htonl(NFS4ERR_RESOURCE);
 115         memcpy(&fh->data[0], p, fh->size);
 116         memset(&fh->data[fh->size], 0, sizeof(fh->data) - fh->size);
 117         return 0;
 118 }
 119
 120 static __be32 decode_bitmap(struct xdr_stream *xdr, uint32_t *bitmap)
 121 {
 122         __be32 *p;
 123         unsigned int attrlen;
 124
 125         p = read_buf(xdr, 4);
 126         if (unlikely(p == NULL))
 127                 return htonl(NFS4ERR_RESOURCE);
 128         attrlen = ntohl(*p);
 129         p = read_buf(xdr, attrlen << 2);
 130         if (unlikely(p == NULL))
 131                 return htonl(NFS4ERR_RESOURCE);
 132         if (likely(attrlen > 0))
 133                 bitmap[0] = ntohl(*p++);
 134         if (attrlen > 1)
 135                 bitmap[1] = ntohl(*p);
 136         return 0;
 137 }
 138
 139 static __be32 decode_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
 140 {
 141         __be32 *p;
 142
 143         p = read_buf(xdr, NFS4_STATEID_SIZE);
 144         if (unlikely(p == NULL))
 145                 return htonl(NFS4ERR_RESOURCE);
 146         memcpy(stateid, p, NFS4_STATEID_SIZE);
 147         return 0;
 148 }
 149
 150 static __be32 decode_compound_hdr_arg(struct xdr_stream *xdr, struct cb_compound_hdr_arg *hdr)
 151 {
 152         __be32 *p;
 153         __be32 status;
 154
 155         status = decode_string(xdr, &hdr->taglen, &hdr->tag);
 156         if (unlikely(status != 0))
 157                 return status;
 158         /* We do not like overly long tags! */
 159         if (hdr->taglen > CB_OP_TAGLEN_MAXSZ - 12) {
 160                 printk("NFS: NFSv4 CALLBACK %s: client sent tag of length %u\n",
 161                                 __func__, hdr->taglen);
 162                 return htonl(NFS4ERR_RESOURCE);
 163         }
 164         p = read_buf(xdr, 12);
 165         if (unlikely(p == NULL))
 166                 return htonl(NFS4ERR_RESOURCE);
 167         hdr->minorversion = ntohl(*p++);
 168         /* Check minor version is zero or one. */
 169         if (hdr->minorversion <= 1) {
 170                 hdr->cb_ident = ntohl(*p++); /* ignored by v4.1 */
 171         } else {
 172                 pr_warn_ratelimited("NFS: %s: NFSv4 server callback with "
 173                         "illegal minor version %u!\n",
 174                         __func__, hdr->minorversion);
 175                 return htonl(NFS4ERR_MINOR_VERS_MISMATCH);
 176         }
 177         hdr->nops = ntohl(*p);
 178         dprintk("%s: minorversion %d nops %d\n", __func__,
 179                 hdr->minorversion, hdr->nops);
 180         return 0;
 181 }
 182
 183 static __be32 decode_op_hdr(struct xdr_stream *xdr, unsigned int *op)
 184 {
 185         __be32 *p;
 186         p = read_buf(xdr, 4);
 187         if (unlikely(p == NULL))
 188                 return htonl(NFS4ERR_RESOURCE_HDR);
 189         *op = ntohl(*p);
 190         return 0;
 191 }
 192
 193 static __be32 decode_getattr_args(struct svc_rqst *rqstp, struct xdr_stream *xdr, struct cb_getattrargs *args)
 194 {
 195         __be32 status;
 196
 197         status = decode_fh(xdr, &args->fh);
 198         if (unlikely(status != 0))
 199                 goto out;
 200         args->addr = svc_addr(rqstp);
 201         status = decode_bitmap(xdr, args->bitmap);
 202 out:
 203         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 204         return status;
 205 }
 206
 207 static __be32 decode_recall_args(struct svc_rqst *rqstp, struct xdr_stream *xdr, struct cb_recallargs *args)
 208 {
 209         __be32 *p;
 210         __be32 status;
 211
 212         args->addr = svc_addr(rqstp);
 213         status = decode_stateid(xdr, &args->stateid);
 214         if (unlikely(status != 0))
 215                 goto out;
 216         p = read_buf(xdr, 4);
 217         if (unlikely(p == NULL)) {
 218                 status = htonl(NFS4ERR_RESOURCE);
 219                 goto out;
 220         }
 221         args->truncate = ntohl(*p);
 222         status = decode_fh(xdr, &args->fh);
 223 out:
 224         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 225         return status;
 226 }
 227
 228 #if defined(CONFIG_NFS_V4_1)
 229
 230 static __be32 decode_layoutrecall_args(struct svc_rqst *rqstp,
 231                                        struct xdr_stream *xdr,
 232                                        struct cb_layoutrecallargs *args)
 233 {
 234         __be32 *p;
 235         __be32 status = 0;
 236         uint32_t iomode;
 237
 238         args->cbl_addr = svc_addr(rqstp);
 239         p = read_buf(xdr, 4 * sizeof(uint32_t));
 240         if (unlikely(p == NULL)) {
 241                 status = htonl(NFS4ERR_BADXDR);
 242                 goto out;
 243         }
 244
 245         args->cbl_layout_type = ntohl(*p++);
 246         /* Depite the spec's xdr, iomode really belongs in the FILE switch,
 247          * as it is unusable and ignored with the other types.
 248          */
 249         iomode = ntohl(*p++);
 250         args->cbl_layoutchanged = ntohl(*p++);
 251         args->cbl_recall_type = ntohl(*p++);
 252
 253         if (args->cbl_recall_type == RETURN_FILE) {
 254                 args->cbl_range.iomode = iomode;
 255                 status = decode_fh(xdr, &args->cbl_fh);
 256                 if (unlikely(status != 0))
 257                         goto out;
 258
 259                 p = read_buf(xdr, 2 * sizeof(uint64_t));
 260                 if (unlikely(p == NULL)) {
 261                         status = htonl(NFS4ERR_BADXDR);
 262                         goto out;
 263                 }
 264                 p = xdr_decode_hyper(p, &args->cbl_range.offset);
 265                 p = xdr_decode_hyper(p, &args->cbl_range.length);
 266                 status = decode_stateid(xdr, &args->cbl_stateid);
 267                 if (unlikely(status != 0))
 268                         goto out;
 269         } else if (args->cbl_recall_type == RETURN_FSID) {
 270                 p = read_buf(xdr, 2 * sizeof(uint64_t));
 271                 if (unlikely(p == NULL)) {
 272                         status = htonl(NFS4ERR_BADXDR);
 273                         goto out;
 274                 }
 275                 p = xdr_decode_hyper(p, &args->cbl_fsid.major);
 276                 p = xdr_decode_hyper(p, &args->cbl_fsid.minor);
 277         } else if (args->cbl_recall_type != RETURN_ALL) {
 278                 status = htonl(NFS4ERR_BADXDR);
 279                 goto out;
 280         }
 281         dprintk("%s: ltype 0x%x iomode %d changed %d recall_type %d\n",
 282                 __func__,
 283                 args->cbl_layout_type, iomode,
 284                 args->cbl_layoutchanged, args->cbl_recall_type);
 285 out:
 286         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 287         return status;
 288 }
 289
 290 static
 291 __be32 decode_devicenotify_args(struct svc_rqst *rqstp,
 292                                 struct xdr_stream *xdr,
 293                                 struct cb_devicenotifyargs *args)
 294 {
 295         __be32 *p;
 296         __be32 status = 0;
 297         u32 tmp;
 298         int n, i;
 299         args->ndevs = 0;
 300
 301         /* Num of device notifications */
 302         p = read_buf(xdr, sizeof(uint32_t));
 303         if (unlikely(p == NULL)) {
 304                 status = htonl(NFS4ERR_BADXDR);
 305                 goto out;
 306         }
 307         n = ntohl(*p++);
 308         if (n <= 0)
 309                 goto out;
 310         if (n > ULONG_MAX / sizeof(*args->devs)) {
 311                 status = htonl(NFS4ERR_BADXDR);
 312                 goto out;
 313         }
 314
 315         args->devs = kmalloc(n * sizeof(*args->devs), GFP_KERNEL);
 316         if (!args->devs) {
 317                 status = htonl(NFS4ERR_DELAY);
 318                 goto out;
 319         }
 320
 321         /* Decode each dev notification */
 322         for (i = 0; i < n; i++) {
 323                 struct cb_devicenotifyitem *dev = &args->devs[i];
 324
 325                 p = read_buf(xdr, (4 * sizeof(uint32_t)) + NFS4_DEVICEID4_SIZE);
 326                 if (unlikely(p == NULL)) {
 327                         status = htonl(NFS4ERR_BADXDR);
 328                         goto err;
 329                 }
 330
 331                 tmp = ntohl(*p++);      /* bitmap size */
 332                 if (tmp != 1) {
 333                         status = htonl(NFS4ERR_INVAL);
 334                         goto err;
 335                 }
 336                 dev->cbd_notify_type = ntohl(*p++);
 337                 if (dev->cbd_notify_type != NOTIFY_DEVICEID4_CHANGE &&
 338                     dev->cbd_notify_type != NOTIFY_DEVICEID4_DELETE) {
 339                         status = htonl(NFS4ERR_INVAL);
 340                         goto err;
 341                 }
 342
 343                 tmp = ntohl(*p++);      /* opaque size */
 344                 if (((dev->cbd_notify_type == NOTIFY_DEVICEID4_CHANGE) &&
 345                      (tmp != NFS4_DEVICEID4_SIZE + 8)) ||
 346                     ((dev->cbd_notify_type == NOTIFY_DEVICEID4_DELETE) &&
 347                      (tmp != NFS4_DEVICEID4_SIZE + 4))) {
 348                         status = htonl(NFS4ERR_INVAL);
 349                         goto err;
 350                 }
 351                 dev->cbd_layout_type = ntohl(*p++);
 352                 memcpy(dev->cbd_dev_id.data, p, NFS4_DEVICEID4_SIZE);
 353                 p += XDR_QUADLEN(NFS4_DEVICEID4_SIZE);
 354
 355                 if (dev->cbd_layout_type == NOTIFY_DEVICEID4_CHANGE) {
 356                         p = read_buf(xdr, sizeof(uint32_t));
 357                         if (unlikely(p == NULL)) {
 358                                 status = htonl(NFS4ERR_BADXDR);
 359                                 goto err;
 360                         }
 361                         dev->cbd_immediate = ntohl(*p++);
 362                 } else {
 363                         dev->cbd_immediate = 0;
 364                 }
 365
 366                 args->ndevs++;
 367
 368                 dprintk("%s: type %d layout 0x%x immediate %d\n",
 369                         __func__, dev->cbd_notify_type, dev->cbd_layout_type,
 370                         dev->cbd_immediate);
 371         }
 372 out:
 373         dprintk("%s: status %d ndevs %d\n",
 374                 __func__, ntohl(status), args->ndevs);
 375         return status;
 376 err:
 377         kfree(args->devs);
 378         goto out;
 379 }
 380
 381 static __be32 decode_sessionid(struct xdr_stream *xdr,
 382                                  struct nfs4_sessionid *sid)
 383 {
 384         __be32 *p;
 385         int len = NFS4_MAX_SESSIONID_LEN;
 386
 387         p = read_buf(xdr, len);
 388         if (unlikely(p == NULL))
 389                 return htonl(NFS4ERR_RESOURCE);
 390
 391         memcpy(sid->data, p, 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(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                                 goto out_free;
 468                 }
 469         }
 470         status = 0;
 471
 472         dprintk("%s: sessionid %x:%x:%x:%x sequenceid %u slotid %u "
 473                 "highestslotid %u cachethis %d nrclists %u\n",
 474                 __func__,
 475                 ((u32 *)&args->csa_sessionid)[0],
 476                 ((u32 *)&args->csa_sessionid)[1],
 477                 ((u32 *)&args->csa_sessionid)[2],
 478                 ((u32 *)&args->csa_sessionid)[3],
 479                 args->csa_sequenceid, args->csa_slotid,
 480                 args->csa_highestslotid, args->csa_cachethis,
 481                 args->csa_nrclists);
 482 out:
 483         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 484         return status;
 485
 486 out_free:
 487         for (i = 0; i < args->csa_nrclists; i++)
 488                 kfree(args->csa_rclists[i].rcl_refcalls);
 489         kfree(args->csa_rclists);
 490         goto out;
 491 }
 492
 493 static __be32 decode_recallany_args(struct svc_rqst *rqstp,
 494                                       struct xdr_stream *xdr,
 495                                       struct cb_recallanyargs *args)
 496 {
 497         uint32_t bitmap[2];
 498         __be32 *p, status;
 499
 500         args->craa_addr = svc_addr(rqstp);
 501         p = read_buf(xdr, 4);
 502         if (unlikely(p == NULL))
 503                 return htonl(NFS4ERR_BADXDR);
 504         args->craa_objs_to_keep = ntohl(*p++);
 505         status = decode_bitmap(xdr, bitmap);
 506         if (unlikely(status))
 507                 return status;
 508         args->craa_type_mask = bitmap[0];
 509
 510         return 0;
 511 }
 512
 513 static __be32 decode_recallslot_args(struct svc_rqst *rqstp,
 514                                         struct xdr_stream *xdr,
 515                                         struct cb_recallslotargs *args)
 516 {
 517         __be32 *p;
 518
 519         args->crsa_addr = svc_addr(rqstp);
 520         p = read_buf(xdr, 4);
 521         if (unlikely(p == NULL))
 522                 return htonl(NFS4ERR_BADXDR);
 523         args->crsa_target_max_slots = 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         int len = NFS4_MAX_SESSIONID_LEN;
 685
 686         p = xdr_reserve_space(xdr, len);
 687         if (unlikely(p == NULL))
 688                 return htonl(NFS4ERR_RESOURCE);
 689
 690         memcpy(p, sid, len);
 691         return 0;
 692 }
 693
 694 static __be32 encode_cb_sequence_res(struct svc_rqst *rqstp,
 695                                        struct xdr_stream *xdr,
 696                                        const struct cb_sequenceres *res)
 697 {
 698         __be32 *p;
 699         __be32 status = res->csr_status;
 700
 701         if (unlikely(status != 0))
 702                 goto out;
 703
 704         encode_sessionid(xdr, &res->csr_sessionid);
 705
 706         p = xdr_reserve_space(xdr, 4 * sizeof(uint32_t));
 707         if (unlikely(p == NULL))
 708                 return htonl(NFS4ERR_RESOURCE);
 709
 710         *p++ = htonl(res->csr_sequenceid);
 711         *p++ = htonl(res->csr_slotid);
 712         *p++ = htonl(res->csr_highestslotid);
 713         *p++ = htonl(res->csr_target_highestslotid);
 714 out:
 715         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 716         return status;
 717 }
 718
 719 static __be32
 720 preprocess_nfs41_op(int nop, unsigned int op_nr, struct callback_op **op)
 721 {
 722         if (op_nr == OP_CB_SEQUENCE) {
 723                 if (nop != 0)
 724                         return htonl(NFS4ERR_SEQUENCE_POS);
 725         } else {
 726                 if (nop == 0)
 727                         return htonl(NFS4ERR_OP_NOT_IN_SESSION);
 728         }
 729
 730         switch (op_nr) {
 731         case OP_CB_GETATTR:
 732         case OP_CB_RECALL:
 733         case OP_CB_SEQUENCE:
 734         case OP_CB_RECALL_ANY:
 735         case OP_CB_RECALL_SLOT:
 736         case OP_CB_LAYOUTRECALL:
 737         case OP_CB_NOTIFY_DEVICEID:
 738                 *op = &callback_ops[op_nr];
 739                 break;
 740
 741         case OP_CB_NOTIFY:
 742         case OP_CB_PUSH_DELEG:
 743         case OP_CB_RECALLABLE_OBJ_AVAIL:
 744         case OP_CB_WANTS_CANCELLED:
 745         case OP_CB_NOTIFY_LOCK:
 746                 return htonl(NFS4ERR_NOTSUPP);
 747
 748         default:
 749                 return htonl(NFS4ERR_OP_ILLEGAL);
 750         }
 751
 752         return htonl(NFS_OK);
 753 }
 754
 755 static void nfs4_callback_free_slot(struct nfs4_session *session)
 756 {
 757         struct nfs4_slot_table *tbl = &session->bc_slot_table;
 758
 759         spin_lock(&tbl->slot_tbl_lock);
 760         /*
 761          * Let the state manager know callback processing done.
 762          * A single slot, so highest used slotid is either 0 or -1
 763          */
 764         tbl->highest_used_slotid = NFS4_NO_SLOT;
 765         nfs4_check_drain_bc_complete(session);
 766         spin_unlock(&tbl->slot_tbl_lock);
 767 }
 768
 769 static void nfs4_cb_free_slot(struct cb_process_state *cps)
 770 {
 771         if (cps->slotid != NFS4_NO_SLOT)
 772                 nfs4_callback_free_slot(cps->clp->cl_session);
 773 }
 774
 775 #else /* CONFIG_NFS_V4_1 */
 776
 777 static __be32
 778 preprocess_nfs41_op(int nop, unsigned int op_nr, struct callback_op **op)
 779 {
 780         return htonl(NFS4ERR_MINOR_VERS_MISMATCH);
 781 }
 782
 783 static void nfs4_cb_free_slot(struct cb_process_state *cps)
 784 {
 785 }
 786 #endif /* CONFIG_NFS_V4_1 */
 787
 788 static __be32
 789 preprocess_nfs4_op(unsigned int op_nr, struct callback_op **op)
 790 {
 791         switch (op_nr) {
 792         case OP_CB_GETATTR:
 793         case OP_CB_RECALL:
 794                 *op = &callback_ops[op_nr];
 795                 break;
 796         default:
 797                 return htonl(NFS4ERR_OP_ILLEGAL);
 798         }
 799
 800         return htonl(NFS_OK);
 801 }
 802
 803 static __be32 process_op(uint32_t minorversion, int nop,
 804                 struct svc_rqst *rqstp,
 805                 struct xdr_stream *xdr_in, void *argp,
 806                 struct xdr_stream *xdr_out, void *resp,
 807                 struct cb_process_state *cps)
 808 {
 809         struct callback_op *op = &callback_ops[0];
 810         unsigned int op_nr;
 811         __be32 status;
 812         long maxlen;
 813         __be32 res;
 814
 815         dprintk("%s: start\n", __func__);
 816         status = decode_op_hdr(xdr_in, &op_nr);
 817         if (unlikely(status))
 818                 return status;
 819
 820         dprintk("%s: minorversion=%d nop=%d op_nr=%u\n",
 821                 __func__, minorversion, nop, op_nr);
 822
 823         status = minorversion ? preprocess_nfs41_op(nop, op_nr, &op) :
 824                                 preprocess_nfs4_op(op_nr, &op);
 825         if (status == htonl(NFS4ERR_OP_ILLEGAL))
 826                 op_nr = OP_CB_ILLEGAL;
 827         if (status)
 828                 goto encode_hdr;
 829
 830         if (cps->drc_status) {
 831                 status = cps->drc_status;
 832                 goto encode_hdr;
 833         }
 834
 835         maxlen = xdr_out->end - xdr_out->p;
 836         if (maxlen > 0 && maxlen < PAGE_SIZE) {
 837                 status = op->decode_args(rqstp, xdr_in, argp);
 838                 if (likely(status == 0))
 839                         status = op->process_op(argp, resp, cps);
 840         } else
 841                 status = htonl(NFS4ERR_RESOURCE);
 842
 843 encode_hdr:
 844         res = encode_op_hdr(xdr_out, op_nr, status);
 845         if (unlikely(res))
 846                 return res;
 847         if (op->encode_res != NULL && status == 0)
 848                 status = op->encode_res(rqstp, xdr_out, resp);
 849         dprintk("%s: done, status = %d\n", __func__, ntohl(status));
 850         return status;
 851 }
 852
 853 /*
 854  * Decode, process and encode a COMPOUND
 855  */
 856 static __be32 nfs4_callback_compound(struct svc_rqst *rqstp, void *argp, void *resp)
 857 {
 858         struct cb_compound_hdr_arg hdr_arg = { 0 };
 859         struct cb_compound_hdr_res hdr_res = { NULL };
 860         struct xdr_stream xdr_in, xdr_out;
 861         __be32 *p, status;
 862         struct cb_process_state cps = {
 863                 .drc_status = 0,
 864                 .clp = NULL,
 865                 .slotid = NFS4_NO_SLOT,
 866                 .net = SVC_NET(rqstp),
 867         };
 868         unsigned int nops = 0;
 869
 870         dprintk("%s: start\n", __func__);
 871
 872         xdr_init_decode(&xdr_in, &rqstp->rq_arg, rqstp->rq_arg.head[0].iov_base);
 873
 874         p = (__be32*)((char *)rqstp->rq_res.head[0].iov_base + rqstp->rq_res.head[0].iov_len);
 875         xdr_init_encode(&xdr_out, &rqstp->rq_res, p);
 876
 877         status = decode_compound_hdr_arg(&xdr_in, &hdr_arg);
 878         if (status == __constant_htonl(NFS4ERR_RESOURCE))
 879                 return rpc_garbage_args;
 880
 881         if (hdr_arg.minorversion == 0) {
 882                 cps.clp = nfs4_find_client_ident(SVC_NET(rqstp), hdr_arg.cb_ident);
 883                 if (!cps.clp || !check_gss_callback_principal(cps.clp, rqstp))
 884                         return rpc_drop_reply;
 885         }
 886
 887         hdr_res.taglen = hdr_arg.taglen;
 888         hdr_res.tag = hdr_arg.tag;
 889         if (encode_compound_hdr_res(&xdr_out, &hdr_res) != 0)
 890                 return rpc_system_err;
 891
 892         while (status == 0 && nops != hdr_arg.nops) {
 893                 status = process_op(hdr_arg.minorversion, nops, rqstp,
 894                                     &xdr_in, argp, &xdr_out, resp, &cps);
 895                 nops++;
 896         }
 897
 898         /* Buffer overflow in decode_ops_hdr or encode_ops_hdr. Return
 899         * resource error in cb_compound status without returning op */
 900         if (unlikely(status == htonl(NFS4ERR_RESOURCE_HDR))) {
 901                 status = htonl(NFS4ERR_RESOURCE);
 902                 nops--;
 903         }
 904
 905         *hdr_res.status = status;
 906         *hdr_res.nops = htonl(nops);
 907         nfs4_cb_free_slot(&cps);
 908         nfs_put_client(cps.clp);
 909         dprintk("%s: done, status = %u\n", __func__, ntohl(status));
 910         return rpc_success;
 911 }
 912
 913 /*
 914  * Define NFS4 callback COMPOUND ops.
 915  */
 916 static struct callback_op callback_ops[] = {
 917         [0] = {
 918                 .res_maxsize = CB_OP_HDR_RES_MAXSZ,
 919         },
 920         [OP_CB_GETATTR] = {
 921                 .process_op = (callback_process_op_t)nfs4_callback_getattr,
 922                 .decode_args = (callback_decode_arg_t)decode_getattr_args,
 923                 .encode_res = (callback_encode_res_t)encode_getattr_res,
 924                 .res_maxsize = CB_OP_GETATTR_RES_MAXSZ,
 925         },
 926         [OP_CB_RECALL] = {
 927                 .process_op = (callback_process_op_t)nfs4_callback_recall,
 928                 .decode_args = (callback_decode_arg_t)decode_recall_args,
 929                 .res_maxsize = CB_OP_RECALL_RES_MAXSZ,
 930         },
 931 #if defined(CONFIG_NFS_V4_1)
 932         [OP_CB_LAYOUTRECALL] = {
 933                 .process_op = (callback_process_op_t)nfs4_callback_layoutrecall,
 934                 .decode_args =
 935                         (callback_decode_arg_t)decode_layoutrecall_args,
 936                 .res_maxsize = CB_OP_LAYOUTRECALL_RES_MAXSZ,
 937         },
 938         [OP_CB_NOTIFY_DEVICEID] = {
 939                 .process_op = (callback_process_op_t)nfs4_callback_devicenotify,
 940                 .decode_args =
 941                         (callback_decode_arg_t)decode_devicenotify_args,
 942                 .res_maxsize = CB_OP_DEVICENOTIFY_RES_MAXSZ,
 943         },
 944         [OP_CB_SEQUENCE] = {
 945                 .process_op = (callback_process_op_t)nfs4_callback_sequence,
 946                 .decode_args = (callback_decode_arg_t)decode_cb_sequence_args,
 947                 .encode_res = (callback_encode_res_t)encode_cb_sequence_res,
 948                 .res_maxsize = CB_OP_SEQUENCE_RES_MAXSZ,
 949         },
 950         [OP_CB_RECALL_ANY] = {
 951                 .process_op = (callback_process_op_t)nfs4_callback_recallany,
 952                 .decode_args = (callback_decode_arg_t)decode_recallany_args,
 953                 .res_maxsize = CB_OP_RECALLANY_RES_MAXSZ,
 954         },
 955         [OP_CB_RECALL_SLOT] = {
 956                 .process_op = (callback_process_op_t)nfs4_callback_recallslot,
 957                 .decode_args = (callback_decode_arg_t)decode_recallslot_args,
 958                 .res_maxsize = CB_OP_RECALLSLOT_RES_MAXSZ,
 959         },
 960 #endif /* CONFIG_NFS_V4_1 */
 961 };
 962
 963 /*
 964  * Define NFS4 callback procedures
 965  */
 966 static struct svc_procedure nfs4_callback_procedures1[] = {
 967         [CB_NULL] = {
 968                 .pc_func = nfs4_callback_null,
 969                 .pc_decode = (kxdrproc_t)nfs4_decode_void,
 970                 .pc_encode = (kxdrproc_t)nfs4_encode_void,
 971                 .pc_xdrressize = 1,
 972         },
 973         [CB_COMPOUND] = {
 974                 .pc_func = nfs4_callback_compound,
 975                 .pc_encode = (kxdrproc_t)nfs4_encode_void,
 976                 .pc_argsize = 256,
 977                 .pc_ressize = 256,
 978                 .pc_xdrressize = NFS4_CALLBACK_BUFSIZE,
 979         }
 980 };
 981
 982 struct svc_version nfs4_callback_version1 = {
 983         .vs_vers = 1,
 984         .vs_nproc = ARRAY_SIZE(nfs4_callback_procedures1),
 985         .vs_proc = nfs4_callback_procedures1,
 986         .vs_xdrsize = NFS4_CALLBACK_XDRSIZE,
 987         .vs_dispatch = NULL,
 988         .vs_hidden = 1,
 989 };
 990
 991 struct svc_version nfs4_callback_version4 = {
 992         .vs_vers = 4,
 993         .vs_nproc = ARRAY_SIZE(nfs4_callback_procedures1),
 994         .vs_proc = nfs4_callback_procedures1,
 995         .vs_xdrsize = NFS4_CALLBACK_XDRSIZE,
 996         .vs_dispatch = NULL,
 997         .vs_hidden = 1,
 998 };