fs/nfs/callback_xdr.c

   1 /*
   2  * linux/fs/nfs/callback_xdr.c
   3  *
   4  * Copyright (C) 2004 Trond Myklebust
   5  *
   6  * NFSv4 callback encode/decode procedures
   7  */
   8 #include <linux/kernel.h>
   9 #include <linux/sunrpc/svc.h>
  10 #include <linux/nfs4.h>
  11 #include <linux/nfs_fs.h>
  12 #include <linux/ratelimit.h>
  13 #include <linux/printk.h>
  14 #include <linux/slab.h>
  15 #include <linux/sunrpc/bc_xprt.h>
  16 #include "nfs4_fs.h"
  17 #include "callback.h"
  18 #include "internal.h"
  19 #include "nfs4session.h"
  20
  21 #define CB_OP_TAGLEN_MAXSZ              (512)
  22 #define CB_OP_HDR_RES_MAXSZ             (2 * 4) // opcode, status
  23 #define CB_OP_GETATTR_BITMAP_MAXSZ      (4 * 4) // bitmap length, 3 bitmaps
  24 #define CB_OP_GETATTR_RES_MAXSZ         (CB_OP_HDR_RES_MAXSZ + \
  25                                          CB_OP_GETATTR_BITMAP_MAXSZ + \
  26                                          /* change, size, ctime, mtime */\
  27                                          (2 + 2 + 3 + 3) * 4)
  28 #define CB_OP_RECALL_RES_MAXSZ          (CB_OP_HDR_RES_MAXSZ)
  29
  30 #if defined(CONFIG_NFS_V4_1)
  31 #define CB_OP_LAYOUTRECALL_RES_MAXSZ    (CB_OP_HDR_RES_MAXSZ)
  32 #define CB_OP_DEVICENOTIFY_RES_MAXSZ    (CB_OP_HDR_RES_MAXSZ)
  33 #define CB_OP_SEQUENCE_RES_MAXSZ        (CB_OP_HDR_RES_MAXSZ + \
  34                                          NFS4_MAX_SESSIONID_LEN + \
  35                                          (1 + 3) * 4) // seqid, 3 slotids
  36 #define CB_OP_RECALLANY_RES_MAXSZ       (CB_OP_HDR_RES_MAXSZ)
  37 #define CB_OP_RECALLSLOT_RES_MAXSZ      (CB_OP_HDR_RES_MAXSZ)
  38 #define CB_OP_NOTIFY_LOCK_RES_MAXSZ     (CB_OP_HDR_RES_MAXSZ)
  39 #endif /* CONFIG_NFS_V4_1 */
  40
  41 #define NFSDBG_FACILITY NFSDBG_CALLBACK
  42
  43 /* Internal error code */
  44 #define NFS4ERR_RESOURCE_HDR    11050
  45
  46 typedef __be32 (*callback_process_op_t)(void *, void *,
  47                                         struct cb_process_state *);
  48 typedef __be32 (*callback_decode_arg_t)(struct svc_rqst *, struct xdr_stream *, void *);
  49 typedef __be32 (*callback_encode_res_t)(struct svc_rqst *, struct xdr_stream *, void *);
  50
  51
  52 struct callback_op {
  53         callback_process_op_t process_op;
  54         callback_decode_arg_t decode_args;
  55         callback_encode_res_t encode_res;
  56         long res_maxsize;
  57 };
  58
  59 static struct callback_op callback_ops[];
  60
  61 static __be32 nfs4_callback_null(struct svc_rqst *rqstp, void *argp, void *resp)
  62 {
  63         return htonl(NFS4_OK);
  64 }
  65
  66 static int nfs4_decode_void(struct svc_rqst *rqstp, __be32 *p, void *dummy)
  67 {
  68         return xdr_argsize_check(rqstp, p);
  69 }
  70
  71 static int nfs4_encode_void(struct svc_rqst *rqstp, __be32 *p, void *dummy)
  72 {
  73         return xdr_ressize_check(rqstp, p);
  74 }
  75
  76 static __be32 *read_buf(struct xdr_stream *xdr, size_t nbytes)
  77 {
  78         __be32 *p;
  79
  80         p = xdr_inline_decode(xdr, nbytes);
  81         if (unlikely(p == NULL))
  82                 printk(KERN_WARNING "NFS: NFSv4 callback reply buffer overflowed!\n");
  83         return p;
  84 }
  85
  86 static __be32 decode_string(struct xdr_stream *xdr, unsigned int *len, 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->data, p, NFS4_STATEID_SIZE);
 151         return 0;
 152 }
 153
 154 static __be32 decode_delegation_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
 155 {
 156         stateid->type = NFS4_DELEGATION_STATEID_TYPE;
 157         return decode_stateid(xdr, stateid);
 158 }
 159
 160 static __be32 decode_compound_hdr_arg(struct xdr_stream *xdr, struct cb_compound_hdr_arg *hdr)
 161 {
 162         __be32 *p;
 163         __be32 status;
 164
 165         status = decode_string(xdr, &hdr->taglen, &hdr->tag);
 166         if (unlikely(status != 0))
 167                 return status;
 168         /* We do not like overly long tags! */
 169         if (hdr->taglen > CB_OP_TAGLEN_MAXSZ) {
 170                 printk("NFS: NFSv4 CALLBACK %s: client sent tag of length %u\n",
 171                                 __func__, hdr->taglen);
 172                 return htonl(NFS4ERR_RESOURCE);
 173         }
 174         p = read_buf(xdr, 12);
 175         if (unlikely(p == NULL))
 176                 return htonl(NFS4ERR_RESOURCE);
 177         hdr->minorversion = ntohl(*p++);
 178         /* Check for minor version support */
 179         if (hdr->minorversion <= NFS4_MAX_MINOR_VERSION) {
 180                 hdr->cb_ident = ntohl(*p++); /* ignored by v4.1 and v4.2 */
 181         } else {
 182                 pr_warn_ratelimited("NFS: %s: NFSv4 server callback with "
 183                         "illegal minor version %u!\n",
 184                         __func__, hdr->minorversion);
 185                 return htonl(NFS4ERR_MINOR_VERS_MISMATCH);
 186         }
 187         hdr->nops = ntohl(*p);
 188         dprintk("%s: minorversion %d nops %d\n", __func__,
 189                 hdr->minorversion, hdr->nops);
 190         return 0;
 191 }
 192
 193 static __be32 decode_op_hdr(struct xdr_stream *xdr, unsigned int *op)
 194 {
 195         __be32 *p;
 196         p = read_buf(xdr, 4);
 197         if (unlikely(p == NULL))
 198                 return htonl(NFS4ERR_RESOURCE_HDR);
 199         *op = ntohl(*p);
 200         return 0;
 201 }
 202
 203 static __be32 decode_getattr_args(struct svc_rqst *rqstp, struct xdr_stream *xdr, struct cb_getattrargs *args)
 204 {
 205         __be32 status;
 206
 207         status = decode_fh(xdr, &args->fh);
 208         if (unlikely(status != 0))
 209                 goto out;
 210         status = decode_bitmap(xdr, args->bitmap);
 211 out:
 212         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 213         return status;
 214 }
 215
 216 static __be32 decode_recall_args(struct svc_rqst *rqstp, struct xdr_stream *xdr, struct cb_recallargs *args)
 217 {
 218         __be32 *p;
 219         __be32 status;
 220
 221         status = decode_delegation_stateid(xdr, &args->stateid);
 222         if (unlikely(status != 0))
 223                 goto out;
 224         p = read_buf(xdr, 4);
 225         if (unlikely(p == NULL)) {
 226                 status = htonl(NFS4ERR_RESOURCE);
 227                 goto out;
 228         }
 229         args->truncate = ntohl(*p);
 230         status = decode_fh(xdr, &args->fh);
 231 out:
 232         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 233         return status;
 234 }
 235
 236 #if defined(CONFIG_NFS_V4_1)
 237 static __be32 decode_layout_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
 238 {
 239         stateid->type = NFS4_LAYOUT_STATEID_TYPE;
 240         return decode_stateid(xdr, stateid);
 241 }
 242
 243 static __be32 decode_layoutrecall_args(struct svc_rqst *rqstp,
 244                                        struct xdr_stream *xdr,
 245                                        struct cb_layoutrecallargs *args)
 246 {
 247         __be32 *p;
 248         __be32 status = 0;
 249         uint32_t iomode;
 250
 251         p = read_buf(xdr, 4 * sizeof(uint32_t));
 252         if (unlikely(p == NULL)) {
 253                 status = htonl(NFS4ERR_BADXDR);
 254                 goto out;
 255         }
 256
 257         args->cbl_layout_type = ntohl(*p++);
 258         /* Depite the spec's xdr, iomode really belongs in the FILE switch,
 259          * as it is unusable and ignored with the other types.
 260          */
 261         iomode = ntohl(*p++);
 262         args->cbl_layoutchanged = ntohl(*p++);
 263         args->cbl_recall_type = ntohl(*p++);
 264
 265         if (args->cbl_recall_type == RETURN_FILE) {
 266                 args->cbl_range.iomode = iomode;
 267                 status = decode_fh(xdr, &args->cbl_fh);
 268                 if (unlikely(status != 0))
 269                         goto out;
 270
 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_range.offset);
 277                 p = xdr_decode_hyper(p, &args->cbl_range.length);
 278                 status = decode_layout_stateid(xdr, &args->cbl_stateid);
 279                 if (unlikely(status != 0))
 280                         goto out;
 281         } else if (args->cbl_recall_type == RETURN_FSID) {
 282                 p = read_buf(xdr, 2 * sizeof(uint64_t));
 283                 if (unlikely(p == NULL)) {
 284                         status = htonl(NFS4ERR_BADXDR);
 285                         goto out;
 286                 }
 287                 p = xdr_decode_hyper(p, &args->cbl_fsid.major);
 288                 p = xdr_decode_hyper(p, &args->cbl_fsid.minor);
 289         } else if (args->cbl_recall_type != RETURN_ALL) {
 290                 status = htonl(NFS4ERR_BADXDR);
 291                 goto out;
 292         }
 293         dprintk("%s: ltype 0x%x iomode %d changed %d recall_type %d\n",
 294                 __func__,
 295                 args->cbl_layout_type, iomode,
 296                 args->cbl_layoutchanged, args->cbl_recall_type);
 297 out:
 298         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 299         return status;
 300 }
 301
 302 static
 303 __be32 decode_devicenotify_args(struct svc_rqst *rqstp,
 304                                 struct xdr_stream *xdr,
 305                                 struct cb_devicenotifyargs *args)
 306 {
 307         __be32 *p;
 308         __be32 status = 0;
 309         u32 tmp;
 310         int n, i;
 311         args->ndevs = 0;
 312
 313         /* Num of device notifications */
 314         p = read_buf(xdr, sizeof(uint32_t));
 315         if (unlikely(p == NULL)) {
 316                 status = htonl(NFS4ERR_BADXDR);
 317                 goto out;
 318         }
 319         n = ntohl(*p++);
 320         if (n <= 0)
 321                 goto out;
 322         if (n > ULONG_MAX / sizeof(*args->devs)) {
 323                 status = htonl(NFS4ERR_BADXDR);
 324                 goto out;
 325         }
 326
 327         args->devs = kmalloc_array(n, sizeof(*args->devs), GFP_KERNEL);
 328         if (!args->devs) {
 329                 status = htonl(NFS4ERR_DELAY);
 330                 goto out;
 331         }
 332
 333         /* Decode each dev notification */
 334         for (i = 0; i < n; i++) {
 335                 struct cb_devicenotifyitem *dev = &args->devs[i];
 336
 337                 p = read_buf(xdr, (4 * sizeof(uint32_t)) + NFS4_DEVICEID4_SIZE);
 338                 if (unlikely(p == NULL)) {
 339                         status = htonl(NFS4ERR_BADXDR);
 340                         goto err;
 341                 }
 342
 343                 tmp = ntohl(*p++);      /* bitmap size */
 344                 if (tmp != 1) {
 345                         status = htonl(NFS4ERR_INVAL);
 346                         goto err;
 347                 }
 348                 dev->cbd_notify_type = ntohl(*p++);
 349                 if (dev->cbd_notify_type != NOTIFY_DEVICEID4_CHANGE &&
 350                     dev->cbd_notify_type != NOTIFY_DEVICEID4_DELETE) {
 351                         status = htonl(NFS4ERR_INVAL);
 352                         goto err;
 353                 }
 354
 355                 tmp = ntohl(*p++);      /* opaque size */
 356                 if (((dev->cbd_notify_type == NOTIFY_DEVICEID4_CHANGE) &&
 357                      (tmp != NFS4_DEVICEID4_SIZE + 8)) ||
 358                     ((dev->cbd_notify_type == NOTIFY_DEVICEID4_DELETE) &&
 359                      (tmp != NFS4_DEVICEID4_SIZE + 4))) {
 360                         status = htonl(NFS4ERR_INVAL);
 361                         goto err;
 362                 }
 363                 dev->cbd_layout_type = ntohl(*p++);
 364                 memcpy(dev->cbd_dev_id.data, p, NFS4_DEVICEID4_SIZE);
 365                 p += XDR_QUADLEN(NFS4_DEVICEID4_SIZE);
 366
 367                 if (dev->cbd_layout_type == NOTIFY_DEVICEID4_CHANGE) {
 368                         p = read_buf(xdr, sizeof(uint32_t));
 369                         if (unlikely(p == NULL)) {
 370                                 status = htonl(NFS4ERR_BADXDR);
 371                                 goto err;
 372                         }
 373                         dev->cbd_immediate = ntohl(*p++);
 374                 } else {
 375                         dev->cbd_immediate = 0;
 376                 }
 377
 378                 args->ndevs++;
 379
 380                 dprintk("%s: type %d layout 0x%x immediate %d\n",
 381                         __func__, dev->cbd_notify_type, dev->cbd_layout_type,
 382                         dev->cbd_immediate);
 383         }
 384 out:
 385         dprintk("%s: status %d ndevs %d\n",
 386                 __func__, ntohl(status), args->ndevs);
 387         return status;
 388 err:
 389         kfree(args->devs);
 390         goto out;
 391 }
 392
 393 static __be32 decode_sessionid(struct xdr_stream *xdr,
 394                                  struct nfs4_sessionid *sid)
 395 {
 396         __be32 *p;
 397
 398         p = read_buf(xdr, NFS4_MAX_SESSIONID_LEN);
 399         if (unlikely(p == NULL))
 400                 return htonl(NFS4ERR_RESOURCE);
 401
 402         memcpy(sid->data, p, NFS4_MAX_SESSIONID_LEN);
 403         return 0;
 404 }
 405
 406 static __be32 decode_rc_list(struct xdr_stream *xdr,
 407                                struct referring_call_list *rc_list)
 408 {
 409         __be32 *p;
 410         int i;
 411         __be32 status;
 412
 413         status = decode_sessionid(xdr, &rc_list->rcl_sessionid);
 414         if (status)
 415                 goto out;
 416
 417         status = htonl(NFS4ERR_RESOURCE);
 418         p = read_buf(xdr, sizeof(uint32_t));
 419         if (unlikely(p == NULL))
 420                 goto out;
 421
 422         rc_list->rcl_nrefcalls = ntohl(*p++);
 423         if (rc_list->rcl_nrefcalls) {
 424                 p = read_buf(xdr,
 425                              rc_list->rcl_nrefcalls * 2 * sizeof(uint32_t));
 426                 if (unlikely(p == NULL))
 427                         goto out;
 428                 rc_list->rcl_refcalls = kmalloc_array(rc_list->rcl_nrefcalls,
 429                                                 sizeof(*rc_list->rcl_refcalls),
 430                                                 GFP_KERNEL);
 431                 if (unlikely(rc_list->rcl_refcalls == NULL))
 432                         goto out;
 433                 for (i = 0; i < rc_list->rcl_nrefcalls; i++) {
 434                         rc_list->rcl_refcalls[i].rc_sequenceid = ntohl(*p++);
 435                         rc_list->rcl_refcalls[i].rc_slotid = ntohl(*p++);
 436                 }
 437         }
 438         status = 0;
 439
 440 out:
 441         return status;
 442 }
 443
 444 static __be32 decode_cb_sequence_args(struct svc_rqst *rqstp,
 445                                         struct xdr_stream *xdr,
 446                                         struct cb_sequenceargs *args)
 447 {
 448         __be32 *p;
 449         int i;
 450         __be32 status;
 451
 452         status = decode_sessionid(xdr, &args->csa_sessionid);
 453         if (status)
 454                 goto out;
 455
 456         status = htonl(NFS4ERR_RESOURCE);
 457         p = read_buf(xdr, 5 * sizeof(uint32_t));
 458         if (unlikely(p == NULL))
 459                 goto out;
 460
 461         args->csa_addr = svc_addr(rqstp);
 462         args->csa_sequenceid = ntohl(*p++);
 463         args->csa_slotid = ntohl(*p++);
 464         args->csa_highestslotid = ntohl(*p++);
 465         args->csa_cachethis = ntohl(*p++);
 466         args->csa_nrclists = ntohl(*p++);
 467         args->csa_rclists = NULL;
 468         if (args->csa_nrclists) {
 469                 args->csa_rclists = kmalloc_array(args->csa_nrclists,
 470                                                   sizeof(*args->csa_rclists),
 471                                                   GFP_KERNEL);
 472                 if (unlikely(args->csa_rclists == NULL))
 473                         goto out;
 474
 475                 for (i = 0; i < args->csa_nrclists; i++) {
 476                         status = decode_rc_list(xdr, &args->csa_rclists[i]);
 477                         if (status) {
 478                                 args->csa_nrclists = i;
 479                                 goto out_free;
 480                         }
 481                 }
 482         }
 483         status = 0;
 484
 485         dprintk("%s: sessionid %x:%x:%x:%x sequenceid %u slotid %u "
 486                 "highestslotid %u cachethis %d nrclists %u\n",
 487                 __func__,
 488                 ((u32 *)&args->csa_sessionid)[0],
 489                 ((u32 *)&args->csa_sessionid)[1],
 490                 ((u32 *)&args->csa_sessionid)[2],
 491                 ((u32 *)&args->csa_sessionid)[3],
 492                 args->csa_sequenceid, args->csa_slotid,
 493                 args->csa_highestslotid, args->csa_cachethis,
 494                 args->csa_nrclists);
 495 out:
 496         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 497         return status;
 498
 499 out_free:
 500         for (i = 0; i < args->csa_nrclists; i++)
 501                 kfree(args->csa_rclists[i].rcl_refcalls);
 502         kfree(args->csa_rclists);
 503         goto out;
 504 }
 505
 506 static __be32 decode_recallany_args(struct svc_rqst *rqstp,
 507                                       struct xdr_stream *xdr,
 508                                       struct cb_recallanyargs *args)
 509 {
 510         uint32_t bitmap[2];
 511         __be32 *p, status;
 512
 513         p = read_buf(xdr, 4);
 514         if (unlikely(p == NULL))
 515                 return htonl(NFS4ERR_BADXDR);
 516         args->craa_objs_to_keep = ntohl(*p++);
 517         status = decode_bitmap(xdr, bitmap);
 518         if (unlikely(status))
 519                 return status;
 520         args->craa_type_mask = bitmap[0];
 521
 522         return 0;
 523 }
 524
 525 static __be32 decode_recallslot_args(struct svc_rqst *rqstp,
 526                                         struct xdr_stream *xdr,
 527                                         struct cb_recallslotargs *args)
 528 {
 529         __be32 *p;
 530
 531         p = read_buf(xdr, 4);
 532         if (unlikely(p == NULL))
 533                 return htonl(NFS4ERR_BADXDR);
 534         args->crsa_target_highest_slotid = ntohl(*p++);
 535         return 0;
 536 }
 537
 538 static __be32 decode_lockowner(struct xdr_stream *xdr, struct cb_notify_lock_args *args)
 539 {
 540         __be32          *p;
 541         unsigned int    len;
 542
 543         p = read_buf(xdr, 12);
 544         if (unlikely(p == NULL))
 545                 return htonl(NFS4ERR_BADXDR);
 546
 547         p = xdr_decode_hyper(p, &args->cbnl_owner.clientid);
 548         len = be32_to_cpu(*p);
 549
 550         p = read_buf(xdr, len);
 551         if (unlikely(p == NULL))
 552                 return htonl(NFS4ERR_BADXDR);
 553
 554         /* Only try to decode if the length is right */
 555         if (len == 20) {
 556                 p += 2; /* skip "lock id:" */
 557                 args->cbnl_owner.s_dev = be32_to_cpu(*p++);
 558                 xdr_decode_hyper(p, &args->cbnl_owner.id);
 559                 args->cbnl_valid = true;
 560         } else {
 561                 args->cbnl_owner.s_dev = 0;
 562                 args->cbnl_owner.id = 0;
 563                 args->cbnl_valid = false;
 564         }
 565         return 0;
 566 }
 567
 568 static __be32 decode_notify_lock_args(struct svc_rqst *rqstp, struct xdr_stream *xdr, struct cb_notify_lock_args *args)
 569 {
 570         __be32 status;
 571
 572         status = decode_fh(xdr, &args->cbnl_fh);
 573         if (unlikely(status != 0))
 574                 goto out;
 575         status = decode_lockowner(xdr, args);
 576 out:
 577         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 578         return status;
 579 }
 580
 581 #endif /* CONFIG_NFS_V4_1 */
 582
 583 static __be32 encode_string(struct xdr_stream *xdr, unsigned int len, const char *str)
 584 {
 585         __be32 *p;
 586
 587         p = xdr_reserve_space(xdr, 4 + len);
 588         if (unlikely(p == NULL))
 589                 return htonl(NFS4ERR_RESOURCE);
 590         xdr_encode_opaque(p, str, len);
 591         return 0;
 592 }
 593
 594 #define CB_SUPPORTED_ATTR0 (FATTR4_WORD0_CHANGE|FATTR4_WORD0_SIZE)
 595 #define CB_SUPPORTED_ATTR1 (FATTR4_WORD1_TIME_METADATA|FATTR4_WORD1_TIME_MODIFY)
 596 static __be32 encode_attr_bitmap(struct xdr_stream *xdr, const uint32_t *bitmap, __be32 **savep)
 597 {
 598         __be32 bm[2];
 599         __be32 *p;
 600
 601         bm[0] = htonl(bitmap[0] & CB_SUPPORTED_ATTR0);
 602         bm[1] = htonl(bitmap[1] & CB_SUPPORTED_ATTR1);
 603         if (bm[1] != 0) {
 604                 p = xdr_reserve_space(xdr, 16);
 605                 if (unlikely(p == NULL))
 606                         return htonl(NFS4ERR_RESOURCE);
 607                 *p++ = htonl(2);
 608                 *p++ = bm[0];
 609                 *p++ = bm[1];
 610         } else if (bm[0] != 0) {
 611                 p = xdr_reserve_space(xdr, 12);
 612                 if (unlikely(p == NULL))
 613                         return htonl(NFS4ERR_RESOURCE);
 614                 *p++ = htonl(1);
 615                 *p++ = bm[0];
 616         } else {
 617                 p = xdr_reserve_space(xdr, 8);
 618                 if (unlikely(p == NULL))
 619                         return htonl(NFS4ERR_RESOURCE);
 620                 *p++ = htonl(0);
 621         }
 622         *savep = p;
 623         return 0;
 624 }
 625
 626 static __be32 encode_attr_change(struct xdr_stream *xdr, const uint32_t *bitmap, uint64_t change)
 627 {
 628         __be32 *p;
 629
 630         if (!(bitmap[0] & FATTR4_WORD0_CHANGE))
 631                 return 0;
 632         p = xdr_reserve_space(xdr, 8);
 633         if (unlikely(!p))
 634                 return htonl(NFS4ERR_RESOURCE);
 635         p = xdr_encode_hyper(p, change);
 636         return 0;
 637 }
 638
 639 static __be32 encode_attr_size(struct xdr_stream *xdr, const uint32_t *bitmap, uint64_t size)
 640 {
 641         __be32 *p;
 642
 643         if (!(bitmap[0] & FATTR4_WORD0_SIZE))
 644                 return 0;
 645         p = xdr_reserve_space(xdr, 8);
 646         if (unlikely(!p))
 647                 return htonl(NFS4ERR_RESOURCE);
 648         p = xdr_encode_hyper(p, size);
 649         return 0;
 650 }
 651
 652 static __be32 encode_attr_time(struct xdr_stream *xdr, const struct timespec *time)
 653 {
 654         __be32 *p;
 655
 656         p = xdr_reserve_space(xdr, 12);
 657         if (unlikely(!p))
 658                 return htonl(NFS4ERR_RESOURCE);
 659         p = xdr_encode_hyper(p, time->tv_sec);
 660         *p = htonl(time->tv_nsec);
 661         return 0;
 662 }
 663
 664 static __be32 encode_attr_ctime(struct xdr_stream *xdr, const uint32_t *bitmap, const struct timespec *time)
 665 {
 666         if (!(bitmap[1] & FATTR4_WORD1_TIME_METADATA))
 667                 return 0;
 668         return encode_attr_time(xdr,time);
 669 }
 670
 671 static __be32 encode_attr_mtime(struct xdr_stream *xdr, const uint32_t *bitmap, const struct timespec *time)
 672 {
 673         if (!(bitmap[1] & FATTR4_WORD1_TIME_MODIFY))
 674                 return 0;
 675         return encode_attr_time(xdr,time);
 676 }
 677
 678 static __be32 encode_compound_hdr_res(struct xdr_stream *xdr, struct cb_compound_hdr_res *hdr)
 679 {
 680         __be32 status;
 681
 682         hdr->status = xdr_reserve_space(xdr, 4);
 683         if (unlikely(hdr->status == NULL))
 684                 return htonl(NFS4ERR_RESOURCE);
 685         status = encode_string(xdr, hdr->taglen, hdr->tag);
 686         if (unlikely(status != 0))
 687                 return status;
 688         hdr->nops = xdr_reserve_space(xdr, 4);
 689         if (unlikely(hdr->nops == NULL))
 690                 return htonl(NFS4ERR_RESOURCE);
 691         return 0;
 692 }
 693
 694 static __be32 encode_op_hdr(struct xdr_stream *xdr, uint32_t op, __be32 res)
 695 {
 696         __be32 *p;
 697
 698         p = xdr_reserve_space(xdr, 8);
 699         if (unlikely(p == NULL))
 700                 return htonl(NFS4ERR_RESOURCE_HDR);
 701         *p++ = htonl(op);
 702         *p = res;
 703         return 0;
 704 }
 705
 706 static __be32 encode_getattr_res(struct svc_rqst *rqstp, struct xdr_stream *xdr, const struct cb_getattrres *res)
 707 {
 708         __be32 *savep = NULL;
 709         __be32 status = res->status;
 710
 711         if (unlikely(status != 0))
 712                 goto out;
 713         status = encode_attr_bitmap(xdr, res->bitmap, &savep);
 714         if (unlikely(status != 0))
 715                 goto out;
 716         status = encode_attr_change(xdr, res->bitmap, res->change_attr);
 717         if (unlikely(status != 0))
 718                 goto out;
 719         status = encode_attr_size(xdr, res->bitmap, res->size);
 720         if (unlikely(status != 0))
 721                 goto out;
 722         status = encode_attr_ctime(xdr, res->bitmap, &res->ctime);
 723         if (unlikely(status != 0))
 724                 goto out;
 725         status = encode_attr_mtime(xdr, res->bitmap, &res->mtime);
 726         *savep = htonl((unsigned int)((char *)xdr->p - (char *)(savep+1)));
 727 out:
 728         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 729         return status;
 730 }
 731
 732 #if defined(CONFIG_NFS_V4_1)
 733
 734 static __be32 encode_sessionid(struct xdr_stream *xdr,
 735                                  const struct nfs4_sessionid *sid)
 736 {
 737         __be32 *p;
 738
 739         p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN);
 740         if (unlikely(p == NULL))
 741                 return htonl(NFS4ERR_RESOURCE);
 742
 743         memcpy(p, sid, NFS4_MAX_SESSIONID_LEN);
 744         return 0;
 745 }
 746
 747 static __be32 encode_cb_sequence_res(struct svc_rqst *rqstp,
 748                                        struct xdr_stream *xdr,
 749                                        const struct cb_sequenceres *res)
 750 {
 751         __be32 *p;
 752         __be32 status = res->csr_status;
 753
 754         if (unlikely(status != 0))
 755                 goto out;
 756
 757         status = encode_sessionid(xdr, &res->csr_sessionid);
 758         if (status)
 759                 goto out;
 760
 761         p = xdr_reserve_space(xdr, 4 * sizeof(uint32_t));
 762         if (unlikely(p == NULL))
 763                 return htonl(NFS4ERR_RESOURCE);
 764
 765         *p++ = htonl(res->csr_sequenceid);
 766         *p++ = htonl(res->csr_slotid);
 767         *p++ = htonl(res->csr_highestslotid);
 768         *p++ = htonl(res->csr_target_highestslotid);
 769 out:
 770         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 771         return status;
 772 }
 773
 774 static __be32
 775 preprocess_nfs41_op(int nop, unsigned int op_nr, struct callback_op **op)
 776 {
 777         if (op_nr == OP_CB_SEQUENCE) {
 778                 if (nop != 0)
 779                         return htonl(NFS4ERR_SEQUENCE_POS);
 780         } else {
 781                 if (nop == 0)
 782                         return htonl(NFS4ERR_OP_NOT_IN_SESSION);
 783         }
 784
 785         switch (op_nr) {
 786         case OP_CB_GETATTR:
 787         case OP_CB_RECALL:
 788         case OP_CB_SEQUENCE:
 789         case OP_CB_RECALL_ANY:
 790         case OP_CB_RECALL_SLOT:
 791         case OP_CB_LAYOUTRECALL:
 792         case OP_CB_NOTIFY_DEVICEID:
 793         case OP_CB_NOTIFY_LOCK:
 794                 *op = &callback_ops[op_nr];
 795                 break;
 796
 797         case OP_CB_NOTIFY:
 798         case OP_CB_PUSH_DELEG:
 799         case OP_CB_RECALLABLE_OBJ_AVAIL:
 800         case OP_CB_WANTS_CANCELLED:
 801                 return htonl(NFS4ERR_NOTSUPP);
 802
 803         default:
 804                 return htonl(NFS4ERR_OP_ILLEGAL);
 805         }
 806
 807         return htonl(NFS_OK);
 808 }
 809
 810 static void nfs4_callback_free_slot(struct nfs4_session *session,
 811                 struct nfs4_slot *slot)
 812 {
 813         struct nfs4_slot_table *tbl = &session->bc_slot_table;
 814
 815         spin_lock(&tbl->slot_tbl_lock);
 816         /*
 817          * Let the state manager know callback processing done.
 818          * A single slot, so highest used slotid is either 0 or -1
 819          */
 820         nfs4_free_slot(tbl, slot);
 821         nfs4_slot_tbl_drain_complete(tbl);
 822         spin_unlock(&tbl->slot_tbl_lock);
 823 }
 824
 825 static void nfs4_cb_free_slot(struct cb_process_state *cps)
 826 {
 827         if (cps->slot) {
 828                 nfs4_callback_free_slot(cps->clp->cl_session, cps->slot);
 829                 cps->slot = NULL;
 830         }
 831 }
 832
 833 #else /* CONFIG_NFS_V4_1 */
 834
 835 static __be32
 836 preprocess_nfs41_op(int nop, unsigned int op_nr, struct callback_op **op)
 837 {
 838         return htonl(NFS4ERR_MINOR_VERS_MISMATCH);
 839 }
 840
 841 static void nfs4_cb_free_slot(struct cb_process_state *cps)
 842 {
 843 }
 844 #endif /* CONFIG_NFS_V4_1 */
 845
 846 #ifdef CONFIG_NFS_V4_2
 847 static __be32
 848 preprocess_nfs42_op(int nop, unsigned int op_nr, struct callback_op **op)
 849 {
 850         __be32 status = preprocess_nfs41_op(nop, op_nr, op);
 851         if (status != htonl(NFS4ERR_OP_ILLEGAL))
 852                 return status;
 853
 854         if (op_nr == OP_CB_OFFLOAD)
 855                 return htonl(NFS4ERR_NOTSUPP);
 856         return htonl(NFS4ERR_OP_ILLEGAL);
 857 }
 858 #else /* CONFIG_NFS_V4_2 */
 859 static __be32
 860 preprocess_nfs42_op(int nop, unsigned int op_nr, struct callback_op **op)
 861 {
 862         return htonl(NFS4ERR_MINOR_VERS_MISMATCH);
 863 }
 864 #endif /* CONFIG_NFS_V4_2 */
 865
 866 static __be32
 867 preprocess_nfs4_op(unsigned int op_nr, struct callback_op **op)
 868 {
 869         switch (op_nr) {
 870         case OP_CB_GETATTR:
 871         case OP_CB_RECALL:
 872                 *op = &callback_ops[op_nr];
 873                 break;
 874         default:
 875                 return htonl(NFS4ERR_OP_ILLEGAL);
 876         }
 877
 878         return htonl(NFS_OK);
 879 }
 880
 881 static __be32 process_op(int nop, struct svc_rqst *rqstp,
 882                 struct xdr_stream *xdr_in, void *argp,
 883                 struct xdr_stream *xdr_out, void *resp,
 884                 struct cb_process_state *cps)
 885 {
 886         struct callback_op *op = &callback_ops[0];
 887         unsigned int op_nr;
 888         __be32 status;
 889         long maxlen;
 890         __be32 res;
 891
 892         dprintk("%s: start\n", __func__);
 893         status = decode_op_hdr(xdr_in, &op_nr);
 894         if (unlikely(status))
 895                 return status;
 896
 897         dprintk("%s: minorversion=%d nop=%d op_nr=%u\n",
 898                 __func__, cps->minorversion, nop, op_nr);
 899
 900         switch (cps->minorversion) {
 901         case 0:
 902                 status = preprocess_nfs4_op(op_nr, &op);
 903                 break;
 904         case 1:
 905                 status = preprocess_nfs41_op(nop, op_nr, &op);
 906                 break;
 907         case 2:
 908                 status = preprocess_nfs42_op(nop, op_nr, &op);
 909                 break;
 910         default:
 911                 status = htonl(NFS4ERR_MINOR_VERS_MISMATCH);
 912         }
 913
 914         if (status == htonl(NFS4ERR_OP_ILLEGAL))
 915                 op_nr = OP_CB_ILLEGAL;
 916         if (status)
 917                 goto encode_hdr;
 918
 919         if (cps->drc_status) {
 920                 status = cps->drc_status;
 921                 goto encode_hdr;
 922         }
 923
 924         maxlen = xdr_out->end - xdr_out->p;
 925         if (maxlen > 0 && maxlen < PAGE_SIZE) {
 926                 status = op->decode_args(rqstp, xdr_in, argp);
 927                 if (likely(status == 0))
 928                         status = op->process_op(argp, resp, cps);
 929         } else
 930                 status = htonl(NFS4ERR_RESOURCE);
 931
 932 encode_hdr:
 933         res = encode_op_hdr(xdr_out, op_nr, status);
 934         if (unlikely(res))
 935                 return res;
 936         if (op->encode_res != NULL && status == 0)
 937                 status = op->encode_res(rqstp, xdr_out, resp);
 938         dprintk("%s: done, status = %d\n", __func__, ntohl(status));
 939         return status;
 940 }
 941
 942 /*
 943  * Decode, process and encode a COMPOUND
 944  */
 945 static __be32 nfs4_callback_compound(struct svc_rqst *rqstp, void *argp, void *resp)
 946 {
 947         struct cb_compound_hdr_arg hdr_arg = { 0 };
 948         struct cb_compound_hdr_res hdr_res = { NULL };
 949         struct xdr_stream xdr_in, xdr_out;
 950         __be32 *p, status;
 951         struct cb_process_state cps = {
 952                 .drc_status = 0,
 953                 .clp = NULL,
 954                 .net = SVC_NET(rqstp),
 955         };
 956         unsigned int nops = 0;
 957
 958         dprintk("%s: start\n", __func__);
 959
 960         xdr_init_decode(&xdr_in, &rqstp->rq_arg, rqstp->rq_arg.head[0].iov_base);
 961
 962         p = (__be32*)((char *)rqstp->rq_res.head[0].iov_base + rqstp->rq_res.head[0].iov_len);
 963         xdr_init_encode(&xdr_out, &rqstp->rq_res, p);
 964
 965         status = decode_compound_hdr_arg(&xdr_in, &hdr_arg);
 966         if (status == htonl(NFS4ERR_RESOURCE))
 967                 return rpc_garbage_args;
 968
 969         if (hdr_arg.minorversion == 0) {
 970                 cps.clp = nfs4_find_client_ident(SVC_NET(rqstp), hdr_arg.cb_ident);
 971                 if (!cps.clp || !check_gss_callback_principal(cps.clp, rqstp))
 972                         goto out_invalidcred;
 973         }
 974
 975         cps.minorversion = hdr_arg.minorversion;
 976         hdr_res.taglen = hdr_arg.taglen;
 977         hdr_res.tag = hdr_arg.tag;
 978         if (encode_compound_hdr_res(&xdr_out, &hdr_res) != 0)
 979                 return rpc_system_err;
 980
 981         while (status == 0 && nops != hdr_arg.nops) {
 982                 status = process_op(nops, rqstp, &xdr_in,
 983                                     argp, &xdr_out, resp, &cps);
 984                 nops++;
 985         }
 986
 987         /* Buffer overflow in decode_ops_hdr or encode_ops_hdr. Return
 988         * resource error in cb_compound status without returning op */
 989         if (unlikely(status == htonl(NFS4ERR_RESOURCE_HDR))) {
 990                 status = htonl(NFS4ERR_RESOURCE);
 991                 nops--;
 992         }
 993
 994         *hdr_res.status = status;
 995         *hdr_res.nops = htonl(nops);
 996         nfs4_cb_free_slot(&cps);
 997         nfs_put_client(cps.clp);
 998         dprintk("%s: done, status = %u\n", __func__, ntohl(status));
 999         return rpc_success;
1000
1001 out_invalidcred:
1002         pr_warn_ratelimited("NFS: NFSv4 callback contains invalid cred\n");
1003         return rpc_autherr_badcred;
1004 }
1005
1006 /*
1007  * Define NFS4 callback COMPOUND ops.
1008  */
1009 static struct callback_op callback_ops[] = {
1010         [0] = {
1011                 .res_maxsize = CB_OP_HDR_RES_MAXSZ,
1012         },
1013         [OP_CB_GETATTR] = {
1014                 .process_op = (callback_process_op_t)nfs4_callback_getattr,
1015                 .decode_args = (callback_decode_arg_t)decode_getattr_args,
1016                 .encode_res = (callback_encode_res_t)encode_getattr_res,
1017                 .res_maxsize = CB_OP_GETATTR_RES_MAXSZ,
1018         },
1019         [OP_CB_RECALL] = {
1020                 .process_op = (callback_process_op_t)nfs4_callback_recall,
1021                 .decode_args = (callback_decode_arg_t)decode_recall_args,
1022                 .res_maxsize = CB_OP_RECALL_RES_MAXSZ,
1023         },
1024 #if defined(CONFIG_NFS_V4_1)
1025         [OP_CB_LAYOUTRECALL] = {
1026                 .process_op = (callback_process_op_t)nfs4_callback_layoutrecall,
1027                 .decode_args =
1028                         (callback_decode_arg_t)decode_layoutrecall_args,
1029                 .res_maxsize = CB_OP_LAYOUTRECALL_RES_MAXSZ,
1030         },
1031         [OP_CB_NOTIFY_DEVICEID] = {
1032                 .process_op = (callback_process_op_t)nfs4_callback_devicenotify,
1033                 .decode_args =
1034                         (callback_decode_arg_t)decode_devicenotify_args,
1035                 .res_maxsize = CB_OP_DEVICENOTIFY_RES_MAXSZ,
1036         },
1037         [OP_CB_SEQUENCE] = {
1038                 .process_op = (callback_process_op_t)nfs4_callback_sequence,
1039                 .decode_args = (callback_decode_arg_t)decode_cb_sequence_args,
1040                 .encode_res = (callback_encode_res_t)encode_cb_sequence_res,
1041                 .res_maxsize = CB_OP_SEQUENCE_RES_MAXSZ,
1042         },
1043         [OP_CB_RECALL_ANY] = {
1044                 .process_op = (callback_process_op_t)nfs4_callback_recallany,
1045                 .decode_args = (callback_decode_arg_t)decode_recallany_args,
1046                 .res_maxsize = CB_OP_RECALLANY_RES_MAXSZ,
1047         },
1048         [OP_CB_RECALL_SLOT] = {
1049                 .process_op = (callback_process_op_t)nfs4_callback_recallslot,
1050                 .decode_args = (callback_decode_arg_t)decode_recallslot_args,
1051                 .res_maxsize = CB_OP_RECALLSLOT_RES_MAXSZ,
1052         },
1053         [OP_CB_NOTIFY_LOCK] = {
1054                 .process_op = (callback_process_op_t)nfs4_callback_notify_lock,
1055                 .decode_args = (callback_decode_arg_t)decode_notify_lock_args,
1056                 .res_maxsize = CB_OP_NOTIFY_LOCK_RES_MAXSZ,
1057         },
1058 #endif /* CONFIG_NFS_V4_1 */
1059 };
1060
1061 /*
1062  * Define NFS4 callback procedures
1063  */
1064 static struct svc_procedure nfs4_callback_procedures1[] = {
1065         [CB_NULL] = {
1066                 .pc_func = nfs4_callback_null,
1067                 .pc_decode = (kxdrproc_t)nfs4_decode_void,
1068                 .pc_encode = (kxdrproc_t)nfs4_encode_void,
1069                 .pc_xdrressize = 1,
1070         },
1071         [CB_COMPOUND] = {
1072                 .pc_func = nfs4_callback_compound,
1073                 .pc_encode = (kxdrproc_t)nfs4_encode_void,
1074                 .pc_argsize = 256,
1075                 .pc_ressize = 256,
1076                 .pc_xdrressize = NFS4_CALLBACK_BUFSIZE,
1077         }
1078 };
1079
1080 struct svc_version nfs4_callback_version1 = {
1081         .vs_vers = 1,
1082         .vs_nproc = ARRAY_SIZE(nfs4_callback_procedures1),
1083         .vs_proc = nfs4_callback_procedures1,
1084         .vs_xdrsize = NFS4_CALLBACK_XDRSIZE,
1085         .vs_dispatch = NULL,
1086         .vs_hidden = 1,
1087 };
1088
1089 struct svc_version nfs4_callback_version4 = {
1090         .vs_vers = 4,
1091         .vs_nproc = ARRAY_SIZE(nfs4_callback_procedures1),
1092         .vs_proc = nfs4_callback_procedures1,
1093         .vs_xdrsize = NFS4_CALLBACK_XDRSIZE,
1094         .vs_dispatch = NULL,
1095         .vs_hidden = 1,
1096 };