fs/nfs/callback_xdr.c

   1 /*
   2  * linux/fs/nfs/callback_xdr.c
   3  *
   4  * Copyright (C) 2004 Trond Myklebust
   5  *
   6  * NFSv4 callback encode/decode procedures
   7  */
   8 #include <linux/kernel.h>
   9 #include <linux/sunrpc/svc.h>
  10 #include <linux/nfs4.h>
  11 #include <linux/nfs_fs.h>
  12 #include <linux/ratelimit.h>
  13 #include <linux/printk.h>
  14 #include <linux/slab.h>
  15 #include <linux/sunrpc/bc_xprt.h>
  16 #include "nfs4_fs.h"
  17 #include "callback.h"
  18 #include "internal.h"
  19 #include "nfs4session.h"
  20
  21 #define CB_OP_TAGLEN_MAXSZ              (512)
  22 #define CB_OP_HDR_RES_MAXSZ             (2 * 4) // opcode, status
  23 #define CB_OP_GETATTR_BITMAP_MAXSZ      (4 * 4) // bitmap length, 3 bitmaps
  24 #define CB_OP_GETATTR_RES_MAXSZ         (CB_OP_HDR_RES_MAXSZ + \
  25                                          CB_OP_GETATTR_BITMAP_MAXSZ + \
  26                                          /* change, size, ctime, mtime */\
  27                                          (2 + 2 + 3 + 3) * 4)
  28 #define CB_OP_RECALL_RES_MAXSZ          (CB_OP_HDR_RES_MAXSZ)
  29
  30 #if defined(CONFIG_NFS_V4_1)
  31 #define CB_OP_LAYOUTRECALL_RES_MAXSZ    (CB_OP_HDR_RES_MAXSZ)
  32 #define CB_OP_DEVICENOTIFY_RES_MAXSZ    (CB_OP_HDR_RES_MAXSZ)
  33 #define CB_OP_SEQUENCE_RES_MAXSZ        (CB_OP_HDR_RES_MAXSZ + \
  34                                          NFS4_MAX_SESSIONID_LEN + \
  35                                          (1 + 3) * 4) // seqid, 3 slotids
  36 #define CB_OP_RECALLANY_RES_MAXSZ       (CB_OP_HDR_RES_MAXSZ)
  37 #define CB_OP_RECALLSLOT_RES_MAXSZ      (CB_OP_HDR_RES_MAXSZ)
  38 #endif /* CONFIG_NFS_V4_1 */
  39
  40 #define NFSDBG_FACILITY NFSDBG_CALLBACK
  41
  42 /* Internal error code */
  43 #define NFS4ERR_RESOURCE_HDR    11050
  44
  45 typedef __be32 (*callback_process_op_t)(void *, void *,
  46                                         struct cb_process_state *);
  47 typedef __be32 (*callback_decode_arg_t)(struct svc_rqst *, struct xdr_stream *, void *);
  48 typedef __be32 (*callback_encode_res_t)(struct svc_rqst *, struct xdr_stream *, void *);
  49
  50
  51 struct callback_op {
  52         callback_process_op_t process_op;
  53         callback_decode_arg_t decode_args;
  54         callback_encode_res_t encode_res;
  55         long res_maxsize;
  56 };
  57
  58 static struct callback_op callback_ops[];
  59
  60 static __be32 nfs4_callback_null(struct svc_rqst *rqstp, void *argp, void *resp)
  61 {
  62         return htonl(NFS4_OK);
  63 }
  64
  65 static int nfs4_decode_void(struct svc_rqst *rqstp, __be32 *p, void *dummy)
  66 {
  67         return xdr_argsize_check(rqstp, p);
  68 }
  69
  70 static int nfs4_encode_void(struct svc_rqst *rqstp, __be32 *p, void *dummy)
  71 {
  72         return xdr_ressize_check(rqstp, p);
  73 }
  74
  75 static __be32 *read_buf(struct xdr_stream *xdr, int nbytes)
  76 {
  77         __be32 *p;
  78
  79         p = xdr_inline_decode(xdr, nbytes);
  80         if (unlikely(p == NULL))
  81                 printk(KERN_WARNING "NFS: NFSv4 callback reply buffer overflowed!\n");
  82         return p;
  83 }
  84
  85 static __be32 decode_string(struct xdr_stream *xdr, unsigned int *len, const char **str)
  86 {
  87         __be32 *p;
  88
  89         p = read_buf(xdr, 4);
  90         if (unlikely(p == NULL))
  91                 return htonl(NFS4ERR_RESOURCE);
  92         *len = ntohl(*p);
  93
  94         if (*len != 0) {
  95                 p = read_buf(xdr, *len);
  96                 if (unlikely(p == NULL))
  97                         return htonl(NFS4ERR_RESOURCE);
  98                 *str = (const char *)p;
  99         } else
 100                 *str = NULL;
 101
 102         return 0;
 103 }
 104
 105 static __be32 decode_fh(struct xdr_stream *xdr, struct nfs_fh *fh)
 106 {
 107         __be32 *p;
 108
 109         p = read_buf(xdr, 4);
 110         if (unlikely(p == NULL))
 111                 return htonl(NFS4ERR_RESOURCE);
 112         fh->size = ntohl(*p);
 113         if (fh->size > NFS4_FHSIZE)
 114                 return htonl(NFS4ERR_BADHANDLE);
 115         p = read_buf(xdr, fh->size);
 116         if (unlikely(p == NULL))
 117                 return htonl(NFS4ERR_RESOURCE);
 118         memcpy(&fh->data[0], p, fh->size);
 119         memset(&fh->data[fh->size], 0, sizeof(fh->data) - fh->size);
 120         return 0;
 121 }
 122
 123 static __be32 decode_bitmap(struct xdr_stream *xdr, uint32_t *bitmap)
 124 {
 125         __be32 *p;
 126         unsigned int attrlen;
 127
 128         p = read_buf(xdr, 4);
 129         if (unlikely(p == NULL))
 130                 return htonl(NFS4ERR_RESOURCE);
 131         attrlen = ntohl(*p);
 132         p = read_buf(xdr, attrlen << 2);
 133         if (unlikely(p == NULL))
 134                 return htonl(NFS4ERR_RESOURCE);
 135         if (likely(attrlen > 0))
 136                 bitmap[0] = ntohl(*p++);
 137         if (attrlen > 1)
 138                 bitmap[1] = ntohl(*p);
 139         return 0;
 140 }
 141
 142 static __be32 decode_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
 143 {
 144         __be32 *p;
 145
 146         p = read_buf(xdr, NFS4_STATEID_SIZE);
 147         if (unlikely(p == NULL))
 148                 return htonl(NFS4ERR_RESOURCE);
 149         memcpy(stateid, p, NFS4_STATEID_SIZE);
 150         return 0;
 151 }
 152
 153 static __be32 decode_compound_hdr_arg(struct xdr_stream *xdr, struct cb_compound_hdr_arg *hdr)
 154 {
 155         __be32 *p;
 156         __be32 status;
 157
 158         status = decode_string(xdr, &hdr->taglen, &hdr->tag);
 159         if (unlikely(status != 0))
 160                 return status;
 161         /* We do not like overly long tags! */
 162         if (hdr->taglen > CB_OP_TAGLEN_MAXSZ) {
 163                 printk("NFS: NFSv4 CALLBACK %s: client sent tag of length %u\n",
 164                                 __func__, hdr->taglen);
 165                 return htonl(NFS4ERR_RESOURCE);
 166         }
 167         p = read_buf(xdr, 12);
 168         if (unlikely(p == NULL))
 169                 return htonl(NFS4ERR_RESOURCE);
 170         hdr->minorversion = ntohl(*p++);
 171         /* Check for minor version support */
 172         if (hdr->minorversion <= NFS4_MAX_MINOR_VERSION) {
 173                 hdr->cb_ident = ntohl(*p++); /* ignored by v4.1 and v4.2 */
 174         } else {
 175                 pr_warn_ratelimited("NFS: %s: NFSv4 server callback with "
 176                         "illegal minor version %u!\n",
 177                         __func__, hdr->minorversion);
 178                 return htonl(NFS4ERR_MINOR_VERS_MISMATCH);
 179         }
 180         hdr->nops = ntohl(*p);
 181         dprintk("%s: minorversion %d nops %d\n", __func__,
 182                 hdr->minorversion, hdr->nops);
 183         return 0;
 184 }
 185
 186 static __be32 decode_op_hdr(struct xdr_stream *xdr, unsigned int *op)
 187 {
 188         __be32 *p;
 189         p = read_buf(xdr, 4);
 190         if (unlikely(p == NULL))
 191                 return htonl(NFS4ERR_RESOURCE_HDR);
 192         *op = ntohl(*p);
 193         return 0;
 194 }
 195
 196 static __be32 decode_getattr_args(struct svc_rqst *rqstp, struct xdr_stream *xdr, struct cb_getattrargs *args)
 197 {
 198         __be32 status;
 199
 200         status = decode_fh(xdr, &args->fh);
 201         if (unlikely(status != 0))
 202                 goto out;
 203         status = decode_bitmap(xdr, args->bitmap);
 204 out:
 205         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 206         return status;
 207 }
 208
 209 static __be32 decode_recall_args(struct svc_rqst *rqstp, struct xdr_stream *xdr, struct cb_recallargs *args)
 210 {
 211         __be32 *p;
 212         __be32 status;
 213
 214         status = decode_stateid(xdr, &args->stateid);
 215         if (unlikely(status != 0))
 216                 goto out;
 217         p = read_buf(xdr, 4);
 218         if (unlikely(p == NULL)) {
 219                 status = htonl(NFS4ERR_RESOURCE);
 220                 goto out;
 221         }
 222         args->truncate = ntohl(*p);
 223         status = decode_fh(xdr, &args->fh);
 224 out:
 225         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 226         return status;
 227 }
 228
 229 #if defined(CONFIG_NFS_V4_1)
 230
 231 static __be32 decode_layoutrecall_args(struct svc_rqst *rqstp,
 232                                        struct xdr_stream *xdr,
 233                                        struct cb_layoutrecallargs *args)
 234 {
 235         __be32 *p;
 236         __be32 status = 0;
 237         uint32_t iomode;
 238
 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_array(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
 386         p = read_buf(xdr, NFS4_MAX_SESSIONID_LEN);
 387         if (unlikely(p == NULL))
 388                 return htonl(NFS4ERR_RESOURCE);
 389
 390         memcpy(sid->data, p, NFS4_MAX_SESSIONID_LEN);
 391         return 0;
 392 }
 393
 394 static __be32 decode_rc_list(struct xdr_stream *xdr,
 395                                struct referring_call_list *rc_list)
 396 {
 397         __be32 *p;
 398         int i;
 399         __be32 status;
 400
 401         status = decode_sessionid(xdr, &rc_list->rcl_sessionid);
 402         if (status)
 403                 goto out;
 404
 405         status = htonl(NFS4ERR_RESOURCE);
 406         p = read_buf(xdr, sizeof(uint32_t));
 407         if (unlikely(p == NULL))
 408                 goto out;
 409
 410         rc_list->rcl_nrefcalls = ntohl(*p++);
 411         if (rc_list->rcl_nrefcalls) {
 412                 p = read_buf(xdr,
 413                              rc_list->rcl_nrefcalls * 2 * sizeof(uint32_t));
 414                 if (unlikely(p == NULL))
 415                         goto out;
 416                 rc_list->rcl_refcalls = kmalloc_array(rc_list->rcl_nrefcalls,
 417                                                 sizeof(*rc_list->rcl_refcalls),
 418                                                 GFP_KERNEL);
 419                 if (unlikely(rc_list->rcl_refcalls == NULL))
 420                         goto out;
 421                 for (i = 0; i < rc_list->rcl_nrefcalls; i++) {
 422                         rc_list->rcl_refcalls[i].rc_sequenceid = ntohl(*p++);
 423                         rc_list->rcl_refcalls[i].rc_slotid = ntohl(*p++);
 424                 }
 425         }
 426         status = 0;
 427
 428 out:
 429         return status;
 430 }
 431
 432 static __be32 decode_cb_sequence_args(struct svc_rqst *rqstp,
 433                                         struct xdr_stream *xdr,
 434                                         struct cb_sequenceargs *args)
 435 {
 436         __be32 *p;
 437         int i;
 438         __be32 status;
 439
 440         status = decode_sessionid(xdr, &args->csa_sessionid);
 441         if (status)
 442                 goto out;
 443
 444         status = htonl(NFS4ERR_RESOURCE);
 445         p = read_buf(xdr, 5 * sizeof(uint32_t));
 446         if (unlikely(p == NULL))
 447                 goto out;
 448
 449         args->csa_addr = svc_addr(rqstp);
 450         args->csa_sequenceid = ntohl(*p++);
 451         args->csa_slotid = ntohl(*p++);
 452         args->csa_highestslotid = ntohl(*p++);
 453         args->csa_cachethis = ntohl(*p++);
 454         args->csa_nrclists = ntohl(*p++);
 455         args->csa_rclists = NULL;
 456         if (args->csa_nrclists) {
 457                 args->csa_rclists = kmalloc_array(args->csa_nrclists,
 458                                                   sizeof(*args->csa_rclists),
 459                                                   GFP_KERNEL);
 460                 if (unlikely(args->csa_rclists == NULL))
 461                         goto out;
 462
 463                 for (i = 0; i < args->csa_nrclists; i++) {
 464                         status = decode_rc_list(xdr, &args->csa_rclists[i]);
 465                         if (status) {
 466                                 args->csa_nrclists = i;
 467                                 goto out_free;
 468                         }
 469                 }
 470         }
 471         status = 0;
 472
 473         dprintk("%s: sessionid %x:%x:%x:%x sequenceid %u slotid %u "
 474                 "highestslotid %u cachethis %d nrclists %u\n",
 475                 __func__,
 476                 ((u32 *)&args->csa_sessionid)[0],
 477                 ((u32 *)&args->csa_sessionid)[1],
 478                 ((u32 *)&args->csa_sessionid)[2],
 479                 ((u32 *)&args->csa_sessionid)[3],
 480                 args->csa_sequenceid, args->csa_slotid,
 481                 args->csa_highestslotid, args->csa_cachethis,
 482                 args->csa_nrclists);
 483 out:
 484         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 485         return status;
 486
 487 out_free:
 488         for (i = 0; i < args->csa_nrclists; i++)
 489                 kfree(args->csa_rclists[i].rcl_refcalls);
 490         kfree(args->csa_rclists);
 491         goto out;
 492 }
 493
 494 static __be32 decode_recallany_args(struct svc_rqst *rqstp,
 495                                       struct xdr_stream *xdr,
 496                                       struct cb_recallanyargs *args)
 497 {
 498         uint32_t bitmap[2];
 499         __be32 *p, status;
 500
 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         p = read_buf(xdr, 4);
 520         if (unlikely(p == NULL))
 521                 return htonl(NFS4ERR_BADXDR);
 522         args->crsa_target_highest_slotid = ntohl(*p++);
 523         return 0;
 524 }
 525
 526 #endif /* CONFIG_NFS_V4_1 */
 527
 528 static __be32 encode_string(struct xdr_stream *xdr, unsigned int len, const char *str)
 529 {
 530         __be32 *p;
 531
 532         p = xdr_reserve_space(xdr, 4 + len);
 533         if (unlikely(p == NULL))
 534                 return htonl(NFS4ERR_RESOURCE);
 535         xdr_encode_opaque(p, str, len);
 536         return 0;
 537 }
 538
 539 #define CB_SUPPORTED_ATTR0 (FATTR4_WORD0_CHANGE|FATTR4_WORD0_SIZE)
 540 #define CB_SUPPORTED_ATTR1 (FATTR4_WORD1_TIME_METADATA|FATTR4_WORD1_TIME_MODIFY)
 541 static __be32 encode_attr_bitmap(struct xdr_stream *xdr, const uint32_t *bitmap, __be32 **savep)
 542 {
 543         __be32 bm[2];
 544         __be32 *p;
 545
 546         bm[0] = htonl(bitmap[0] & CB_SUPPORTED_ATTR0);
 547         bm[1] = htonl(bitmap[1] & CB_SUPPORTED_ATTR1);
 548         if (bm[1] != 0) {
 549                 p = xdr_reserve_space(xdr, 16);
 550                 if (unlikely(p == NULL))
 551                         return htonl(NFS4ERR_RESOURCE);
 552                 *p++ = htonl(2);
 553                 *p++ = bm[0];
 554                 *p++ = bm[1];
 555         } else if (bm[0] != 0) {
 556                 p = xdr_reserve_space(xdr, 12);
 557                 if (unlikely(p == NULL))
 558                         return htonl(NFS4ERR_RESOURCE);
 559                 *p++ = htonl(1);
 560                 *p++ = bm[0];
 561         } else {
 562                 p = xdr_reserve_space(xdr, 8);
 563                 if (unlikely(p == NULL))
 564                         return htonl(NFS4ERR_RESOURCE);
 565                 *p++ = htonl(0);
 566         }
 567         *savep = p;
 568         return 0;
 569 }
 570
 571 static __be32 encode_attr_change(struct xdr_stream *xdr, const uint32_t *bitmap, uint64_t change)
 572 {
 573         __be32 *p;
 574
 575         if (!(bitmap[0] & FATTR4_WORD0_CHANGE))
 576                 return 0;
 577         p = xdr_reserve_space(xdr, 8);
 578         if (unlikely(!p))
 579                 return htonl(NFS4ERR_RESOURCE);
 580         p = xdr_encode_hyper(p, change);
 581         return 0;
 582 }
 583
 584 static __be32 encode_attr_size(struct xdr_stream *xdr, const uint32_t *bitmap, uint64_t size)
 585 {
 586         __be32 *p;
 587
 588         if (!(bitmap[0] & FATTR4_WORD0_SIZE))
 589                 return 0;
 590         p = xdr_reserve_space(xdr, 8);
 591         if (unlikely(!p))
 592                 return htonl(NFS4ERR_RESOURCE);
 593         p = xdr_encode_hyper(p, size);
 594         return 0;
 595 }
 596
 597 static __be32 encode_attr_time(struct xdr_stream *xdr, const struct timespec *time)
 598 {
 599         __be32 *p;
 600
 601         p = xdr_reserve_space(xdr, 12);
 602         if (unlikely(!p))
 603                 return htonl(NFS4ERR_RESOURCE);
 604         p = xdr_encode_hyper(p, time->tv_sec);
 605         *p = htonl(time->tv_nsec);
 606         return 0;
 607 }
 608
 609 static __be32 encode_attr_ctime(struct xdr_stream *xdr, const uint32_t *bitmap, const struct timespec *time)
 610 {
 611         if (!(bitmap[1] & FATTR4_WORD1_TIME_METADATA))
 612                 return 0;
 613         return encode_attr_time(xdr,time);
 614 }
 615
 616 static __be32 encode_attr_mtime(struct xdr_stream *xdr, const uint32_t *bitmap, const struct timespec *time)
 617 {
 618         if (!(bitmap[1] & FATTR4_WORD1_TIME_MODIFY))
 619                 return 0;
 620         return encode_attr_time(xdr,time);
 621 }
 622
 623 static __be32 encode_compound_hdr_res(struct xdr_stream *xdr, struct cb_compound_hdr_res *hdr)
 624 {
 625         __be32 status;
 626
 627         hdr->status = xdr_reserve_space(xdr, 4);
 628         if (unlikely(hdr->status == NULL))
 629                 return htonl(NFS4ERR_RESOURCE);
 630         status = encode_string(xdr, hdr->taglen, hdr->tag);
 631         if (unlikely(status != 0))
 632                 return status;
 633         hdr->nops = xdr_reserve_space(xdr, 4);
 634         if (unlikely(hdr->nops == NULL))
 635                 return htonl(NFS4ERR_RESOURCE);
 636         return 0;
 637 }
 638
 639 static __be32 encode_op_hdr(struct xdr_stream *xdr, uint32_t op, __be32 res)
 640 {
 641         __be32 *p;
 642
 643         p = xdr_reserve_space(xdr, 8);
 644         if (unlikely(p == NULL))
 645                 return htonl(NFS4ERR_RESOURCE_HDR);
 646         *p++ = htonl(op);
 647         *p = res;
 648         return 0;
 649 }
 650
 651 static __be32 encode_getattr_res(struct svc_rqst *rqstp, struct xdr_stream *xdr, const struct cb_getattrres *res)
 652 {
 653         __be32 *savep = NULL;
 654         __be32 status = res->status;
 655
 656         if (unlikely(status != 0))
 657                 goto out;
 658         status = encode_attr_bitmap(xdr, res->bitmap, &savep);
 659         if (unlikely(status != 0))
 660                 goto out;
 661         status = encode_attr_change(xdr, res->bitmap, res->change_attr);
 662         if (unlikely(status != 0))
 663                 goto out;
 664         status = encode_attr_size(xdr, res->bitmap, res->size);
 665         if (unlikely(status != 0))
 666                 goto out;
 667         status = encode_attr_ctime(xdr, res->bitmap, &res->ctime);
 668         if (unlikely(status != 0))
 669                 goto out;
 670         status = encode_attr_mtime(xdr, res->bitmap, &res->mtime);
 671         *savep = htonl((unsigned int)((char *)xdr->p - (char *)(savep+1)));
 672 out:
 673         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 674         return status;
 675 }
 676
 677 #if defined(CONFIG_NFS_V4_1)
 678
 679 static __be32 encode_sessionid(struct xdr_stream *xdr,
 680                                  const struct nfs4_sessionid *sid)
 681 {
 682         __be32 *p;
 683
 684         p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN);
 685         if (unlikely(p == NULL))
 686                 return htonl(NFS4ERR_RESOURCE);
 687
 688         memcpy(p, sid, NFS4_MAX_SESSIONID_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         __be32 status = res->csr_status;
 698
 699         if (unlikely(status != 0))
 700                 goto out;
 701
 702         status = encode_sessionid(xdr, &res->csr_sessionid);
 703         if (status)
 704                 goto out;
 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_slot_tbl_drain_complete(tbl);
 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 #ifdef CONFIG_NFS_V4_2
 789 static __be32
 790 preprocess_nfs42_op(int nop, unsigned int op_nr, struct callback_op **op)
 791 {
 792         __be32 status = preprocess_nfs41_op(nop, op_nr, op);
 793         if (status != htonl(NFS4ERR_OP_ILLEGAL))
 794                 return status;
 795
 796         if (op_nr == OP_CB_OFFLOAD)
 797                 return htonl(NFS4ERR_NOTSUPP);
 798         return htonl(NFS4ERR_OP_ILLEGAL);
 799 }
 800 #else /* CONFIG_NFS_V4_2 */
 801 static __be32
 802 preprocess_nfs42_op(int nop, unsigned int op_nr, struct callback_op **op)
 803 {
 804         return htonl(NFS4ERR_MINOR_VERS_MISMATCH);
 805 }
 806 #endif /* CONFIG_NFS_V4_2 */
 807
 808 static __be32
 809 preprocess_nfs4_op(unsigned int op_nr, struct callback_op **op)
 810 {
 811         switch (op_nr) {
 812         case OP_CB_GETATTR:
 813         case OP_CB_RECALL:
 814                 *op = &callback_ops[op_nr];
 815                 break;
 816         default:
 817                 return htonl(NFS4ERR_OP_ILLEGAL);
 818         }
 819
 820         return htonl(NFS_OK);
 821 }
 822
 823 static __be32 process_op(int nop, struct svc_rqst *rqstp,
 824                 struct xdr_stream *xdr_in, void *argp,
 825                 struct xdr_stream *xdr_out, void *resp,
 826                 struct cb_process_state *cps)
 827 {
 828         struct callback_op *op = &callback_ops[0];
 829         unsigned int op_nr;
 830         __be32 status;
 831         long maxlen;
 832         __be32 res;
 833
 834         dprintk("%s: start\n", __func__);
 835         status = decode_op_hdr(xdr_in, &op_nr);
 836         if (unlikely(status))
 837                 return status;
 838
 839         dprintk("%s: minorversion=%d nop=%d op_nr=%u\n",
 840                 __func__, cps->minorversion, nop, op_nr);
 841
 842         switch (cps->minorversion) {
 843         case 0:
 844                 status = preprocess_nfs4_op(op_nr, &op);
 845                 break;
 846         case 1:
 847                 status = preprocess_nfs41_op(nop, op_nr, &op);
 848                 break;
 849         case 2:
 850                 status = preprocess_nfs42_op(nop, op_nr, &op);
 851                 break;
 852         default:
 853                 status = htonl(NFS4ERR_MINOR_VERS_MISMATCH);
 854         }
 855
 856         if (status == htonl(NFS4ERR_OP_ILLEGAL))
 857                 op_nr = OP_CB_ILLEGAL;
 858         if (status)
 859                 goto encode_hdr;
 860
 861         if (cps->drc_status) {
 862                 status = cps->drc_status;
 863                 goto encode_hdr;
 864         }
 865
 866         maxlen = xdr_out->end - xdr_out->p;
 867         if (maxlen > 0 && maxlen < PAGE_SIZE) {
 868                 status = op->decode_args(rqstp, xdr_in, argp);
 869                 if (likely(status == 0))
 870                         status = op->process_op(argp, resp, cps);
 871         } else
 872                 status = htonl(NFS4ERR_RESOURCE);
 873
 874 encode_hdr:
 875         res = encode_op_hdr(xdr_out, op_nr, status);
 876         if (unlikely(res))
 877                 return res;
 878         if (op->encode_res != NULL && status == 0)
 879                 status = op->encode_res(rqstp, xdr_out, resp);
 880         dprintk("%s: done, status = %d\n", __func__, ntohl(status));
 881         return status;
 882 }
 883
 884 /*
 885  * Decode, process and encode a COMPOUND
 886  */
 887 static __be32 nfs4_callback_compound(struct svc_rqst *rqstp, void *argp, void *resp)
 888 {
 889         struct cb_compound_hdr_arg hdr_arg = { 0 };
 890         struct cb_compound_hdr_res hdr_res = { NULL };
 891         struct xdr_stream xdr_in, xdr_out;
 892         __be32 *p, status;
 893         struct cb_process_state cps = {
 894                 .drc_status = 0,
 895                 .clp = NULL,
 896                 .slotid = NFS4_NO_SLOT,
 897                 .net = SVC_NET(rqstp),
 898         };
 899         unsigned int nops = 0;
 900
 901         dprintk("%s: start\n", __func__);
 902
 903         xdr_init_decode(&xdr_in, &rqstp->rq_arg, rqstp->rq_arg.head[0].iov_base);
 904
 905         p = (__be32*)((char *)rqstp->rq_res.head[0].iov_base + rqstp->rq_res.head[0].iov_len);
 906         xdr_init_encode(&xdr_out, &rqstp->rq_res, p);
 907
 908         status = decode_compound_hdr_arg(&xdr_in, &hdr_arg);
 909         if (status == htonl(NFS4ERR_RESOURCE))
 910                 return rpc_garbage_args;
 911
 912         if (hdr_arg.minorversion == 0) {
 913                 cps.clp = nfs4_find_client_ident(SVC_NET(rqstp), hdr_arg.cb_ident);
 914                 if (!cps.clp || !check_gss_callback_principal(cps.clp, rqstp)) {
 915                         if (cps.clp)
 916                                 nfs_put_client(cps.clp);
 917                         goto out_invalidcred;
 918                 }
 919         }
 920
 921         cps.minorversion = hdr_arg.minorversion;
 922         hdr_res.taglen = hdr_arg.taglen;
 923         hdr_res.tag = hdr_arg.tag;
 924         if (encode_compound_hdr_res(&xdr_out, &hdr_res) != 0) {
 925                 if (cps.clp)
 926                         nfs_put_client(cps.clp);
 927                 return rpc_system_err;
 928         }
 929         while (status == 0 && nops != hdr_arg.nops) {
 930                 status = process_op(nops, rqstp, &xdr_in,
 931                                     argp, &xdr_out, resp, &cps);
 932                 nops++;
 933         }
 934
 935         /* Buffer overflow in decode_ops_hdr or encode_ops_hdr. Return
 936         * resource error in cb_compound status without returning op */
 937         if (unlikely(status == htonl(NFS4ERR_RESOURCE_HDR))) {
 938                 status = htonl(NFS4ERR_RESOURCE);
 939                 nops--;
 940         }
 941
 942         *hdr_res.status = status;
 943         *hdr_res.nops = htonl(nops);
 944         nfs4_cb_free_slot(&cps);
 945         nfs_put_client(cps.clp);
 946         dprintk("%s: done, status = %u\n", __func__, ntohl(status));
 947         return rpc_success;
 948
 949 out_invalidcred:
 950         pr_warn_ratelimited("NFS: NFSv4 callback contains invalid cred\n");
 951         return rpc_autherr_badcred;
 952 }
 953
 954 /*
 955  * Define NFS4 callback COMPOUND ops.
 956  */
 957 static struct callback_op callback_ops[] = {
 958         [0] = {
 959                 .res_maxsize = CB_OP_HDR_RES_MAXSZ,
 960         },
 961         [OP_CB_GETATTR] = {
 962                 .process_op = (callback_process_op_t)nfs4_callback_getattr,
 963                 .decode_args = (callback_decode_arg_t)decode_getattr_args,
 964                 .encode_res = (callback_encode_res_t)encode_getattr_res,
 965                 .res_maxsize = CB_OP_GETATTR_RES_MAXSZ,
 966         },
 967         [OP_CB_RECALL] = {
 968                 .process_op = (callback_process_op_t)nfs4_callback_recall,
 969                 .decode_args = (callback_decode_arg_t)decode_recall_args,
 970                 .res_maxsize = CB_OP_RECALL_RES_MAXSZ,
 971         },
 972 #if defined(CONFIG_NFS_V4_1)
 973         [OP_CB_LAYOUTRECALL] = {
 974                 .process_op = (callback_process_op_t)nfs4_callback_layoutrecall,
 975                 .decode_args =
 976                         (callback_decode_arg_t)decode_layoutrecall_args,
 977                 .res_maxsize = CB_OP_LAYOUTRECALL_RES_MAXSZ,
 978         },
 979         [OP_CB_NOTIFY_DEVICEID] = {
 980                 .process_op = (callback_process_op_t)nfs4_callback_devicenotify,
 981                 .decode_args =
 982                         (callback_decode_arg_t)decode_devicenotify_args,
 983                 .res_maxsize = CB_OP_DEVICENOTIFY_RES_MAXSZ,
 984         },
 985         [OP_CB_SEQUENCE] = {
 986                 .process_op = (callback_process_op_t)nfs4_callback_sequence,
 987                 .decode_args = (callback_decode_arg_t)decode_cb_sequence_args,
 988                 .encode_res = (callback_encode_res_t)encode_cb_sequence_res,
 989                 .res_maxsize = CB_OP_SEQUENCE_RES_MAXSZ,
 990         },
 991         [OP_CB_RECALL_ANY] = {
 992                 .process_op = (callback_process_op_t)nfs4_callback_recallany,
 993                 .decode_args = (callback_decode_arg_t)decode_recallany_args,
 994                 .res_maxsize = CB_OP_RECALLANY_RES_MAXSZ,
 995         },
 996         [OP_CB_RECALL_SLOT] = {
 997                 .process_op = (callback_process_op_t)nfs4_callback_recallslot,
 998                 .decode_args = (callback_decode_arg_t)decode_recallslot_args,
 999                 .res_maxsize = CB_OP_RECALLSLOT_RES_MAXSZ,
1000         },
1001 #endif /* CONFIG_NFS_V4_1 */
1002 };
1003
1004 /*
1005  * Define NFS4 callback procedures
1006  */
1007 static struct svc_procedure nfs4_callback_procedures1[] = {
1008         [CB_NULL] = {
1009                 .pc_func = nfs4_callback_null,
1010                 .pc_decode = (kxdrproc_t)nfs4_decode_void,
1011                 .pc_encode = (kxdrproc_t)nfs4_encode_void,
1012                 .pc_xdrressize = 1,
1013         },
1014         [CB_COMPOUND] = {
1015                 .pc_func = nfs4_callback_compound,
1016                 .pc_encode = (kxdrproc_t)nfs4_encode_void,
1017                 .pc_argsize = 256,
1018                 .pc_ressize = 256,
1019                 .pc_xdrressize = NFS4_CALLBACK_BUFSIZE,
1020         }
1021 };
1022
1023 struct svc_version nfs4_callback_version1 = {
1024         .vs_vers = 1,
1025         .vs_nproc = ARRAY_SIZE(nfs4_callback_procedures1),
1026         .vs_proc = nfs4_callback_procedures1,
1027         .vs_xdrsize = NFS4_CALLBACK_XDRSIZE,
1028         .vs_dispatch = NULL,
1029         .vs_hidden = 1,
1030 };
1031
1032 struct svc_version nfs4_callback_version4 = {
1033         .vs_vers = 4,
1034         .vs_nproc = ARRAY_SIZE(nfs4_callback_procedures1),
1035         .vs_proc = nfs4_callback_procedures1,
1036         .vs_xdrsize = NFS4_CALLBACK_XDRSIZE,
1037         .vs_dispatch = NULL,
1038         .vs_hidden = 1,
1039 };