1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * linux/fs/nfs/nfs2xdr.c 4 * 5 * XDR functions to encode/decode NFS RPC arguments and results. 6 * 7 * Copyright (C) 1992, 1993, 1994 Rick Sladkey 8 * Copyright (C) 1996 Olaf Kirch 9 * 04 Aug 1998 Ion Badulescu <ionut@cs.columbia.edu> 10 * FIFO's need special handling in NFSv2 11 */ 12 13 #include <linux/param.h> 14 #include <linux/time.h> 15 #include <linux/mm.h> 16 #include <linux/errno.h> 17 #include <linux/string.h> 18 #include <linux/in.h> 19 #include <linux/pagemap.h> 20 #include <linux/proc_fs.h> 21 #include <linux/sunrpc/clnt.h> 22 #include <linux/nfs.h> 23 #include <linux/nfs2.h> 24 #include <linux/nfs_fs.h> 25 #include "nfstrace.h" 26 #include "internal.h" 27 28 #define NFSDBG_FACILITY NFSDBG_XDR 29 30 /* Mapping from NFS error code to "errno" error code. */ 31 #define errno_NFSERR_IO EIO 32 33 /* 34 * Declare the space requirements for NFS arguments and replies as 35 * number of 32bit-words 36 */ 37 #define NFS_fhandle_sz (8) 38 #define NFS_sattr_sz (8) 39 #define NFS_filename_sz (1+(NFS2_MAXNAMLEN>>2)) 40 #define NFS_path_sz (1+(NFS2_MAXPATHLEN>>2)) 41 #define NFS_fattr_sz (17) 42 #define NFS_info_sz (5) 43 #define NFS_entry_sz (NFS_filename_sz+3) 44 45 #define NFS_diropargs_sz (NFS_fhandle_sz+NFS_filename_sz) 46 #define NFS_removeargs_sz (NFS_fhandle_sz+NFS_filename_sz) 47 #define NFS_sattrargs_sz (NFS_fhandle_sz+NFS_sattr_sz) 48 #define NFS_readlinkargs_sz (NFS_fhandle_sz) 49 #define NFS_readargs_sz (NFS_fhandle_sz+3) 50 #define NFS_writeargs_sz (NFS_fhandle_sz+4) 51 #define NFS_createargs_sz (NFS_diropargs_sz+NFS_sattr_sz) 52 #define NFS_renameargs_sz (NFS_diropargs_sz+NFS_diropargs_sz) 53 #define NFS_linkargs_sz (NFS_fhandle_sz+NFS_diropargs_sz) 54 #define NFS_symlinkargs_sz (NFS_diropargs_sz+1+NFS_sattr_sz) 55 #define NFS_readdirargs_sz (NFS_fhandle_sz+2) 56 57 #define NFS_attrstat_sz (1+NFS_fattr_sz) 58 #define NFS_diropres_sz (1+NFS_fhandle_sz+NFS_fattr_sz) 59 #define NFS_readlinkres_sz (2+1) 60 #define NFS_readres_sz (1+NFS_fattr_sz+1+1) 61 #define NFS_writeres_sz (NFS_attrstat_sz) 62 #define NFS_stat_sz (1) 63 #define NFS_readdirres_sz (1+1) 64 #define NFS_statfsres_sz (1+NFS_info_sz) 65 66 static int nfs_stat_to_errno(enum nfs_stat); 67 68 /* 69 * Encode/decode NFSv2 basic data types 70 * 71 * Basic NFSv2 data types are defined in section 2.3 of RFC 1094: 72 * "NFS: Network File System Protocol Specification". 73 * 74 * Not all basic data types have their own encoding and decoding 75 * functions. For run-time efficiency, some data types are encoded 76 * or decoded inline. 77 */ 78 79 static struct user_namespace *rpc_userns(const struct rpc_clnt *clnt) 80 { 81 if (clnt && clnt->cl_cred) 82 return clnt->cl_cred->user_ns; 83 return &init_user_ns; 84 } 85 86 static struct user_namespace *rpc_rqst_userns(const struct rpc_rqst *rqstp) 87 { 88 if (rqstp->rq_task) 89 return rpc_userns(rqstp->rq_task->tk_client); 90 return &init_user_ns; 91 } 92 93 /* 94 * typedef opaque nfsdata<>; 95 */ 96 static int decode_nfsdata(struct xdr_stream *xdr, struct nfs_pgio_res *result) 97 { 98 u32 recvd, count; 99 __be32 *p; 100 101 p = xdr_inline_decode(xdr, 4); 102 if (unlikely(!p)) 103 return -EIO; 104 count = be32_to_cpup(p); 105 recvd = xdr_read_pages(xdr, count); 106 if (unlikely(count > recvd)) 107 goto out_cheating; 108 out: 109 result->eof = 0; /* NFSv2 does not pass EOF flag on the wire. */ 110 result->count = count; 111 return count; 112 out_cheating: 113 dprintk("NFS: server cheating in read result: " 114 "count %u > recvd %u\n", count, recvd); 115 count = recvd; 116 goto out; 117 } 118 119 /* 120 * enum stat { 121 * NFS_OK = 0, 122 * NFSERR_PERM = 1, 123 * NFSERR_NOENT = 2, 124 * NFSERR_IO = 5, 125 * NFSERR_NXIO = 6, 126 * NFSERR_ACCES = 13, 127 * NFSERR_EXIST = 17, 128 * NFSERR_NODEV = 19, 129 * NFSERR_NOTDIR = 20, 130 * NFSERR_ISDIR = 21, 131 * NFSERR_FBIG = 27, 132 * NFSERR_NOSPC = 28, 133 * NFSERR_ROFS = 30, 134 * NFSERR_NAMETOOLONG = 63, 135 * NFSERR_NOTEMPTY = 66, 136 * NFSERR_DQUOT = 69, 137 * NFSERR_STALE = 70, 138 * NFSERR_WFLUSH = 99 139 * }; 140 */ 141 static int decode_stat(struct xdr_stream *xdr, enum nfs_stat *status) 142 { 143 __be32 *p; 144 145 p = xdr_inline_decode(xdr, 4); 146 if (unlikely(!p)) 147 return -EIO; 148 if (unlikely(*p != cpu_to_be32(NFS_OK))) 149 goto out_status; 150 *status = 0; 151 return 0; 152 out_status: 153 *status = be32_to_cpup(p); 154 trace_nfs_xdr_status((int)*status); 155 return 0; 156 } 157 158 /* 159 * 2.3.2. ftype 160 * 161 * enum ftype { 162 * NFNON = 0, 163 * NFREG = 1, 164 * NFDIR = 2, 165 * NFBLK = 3, 166 * NFCHR = 4, 167 * NFLNK = 5 168 * }; 169 * 170 */ 171 static __be32 *xdr_decode_ftype(__be32 *p, u32 *type) 172 { 173 *type = be32_to_cpup(p++); 174 if (unlikely(*type > NF2FIFO)) 175 *type = NFBAD; 176 return p; 177 } 178 179 /* 180 * 2.3.3. fhandle 181 * 182 * typedef opaque fhandle[FHSIZE]; 183 */ 184 static void encode_fhandle(struct xdr_stream *xdr, const struct nfs_fh *fh) 185 { 186 __be32 *p; 187 188 p = xdr_reserve_space(xdr, NFS2_FHSIZE); 189 memcpy(p, fh->data, NFS2_FHSIZE); 190 } 191 192 static int decode_fhandle(struct xdr_stream *xdr, struct nfs_fh *fh) 193 { 194 __be32 *p; 195 196 p = xdr_inline_decode(xdr, NFS2_FHSIZE); 197 if (unlikely(!p)) 198 return -EIO; 199 fh->size = NFS2_FHSIZE; 200 memcpy(fh->data, p, NFS2_FHSIZE); 201 return 0; 202 } 203 204 /* 205 * 2.3.4. timeval 206 * 207 * struct timeval { 208 * unsigned int seconds; 209 * unsigned int useconds; 210 * }; 211 */ 212 static __be32 *xdr_encode_time(__be32 *p, const struct timespec *timep) 213 { 214 *p++ = cpu_to_be32(timep->tv_sec); 215 if (timep->tv_nsec != 0) 216 *p++ = cpu_to_be32(timep->tv_nsec / NSEC_PER_USEC); 217 else 218 *p++ = cpu_to_be32(0); 219 return p; 220 } 221 222 /* 223 * Passing the invalid value useconds=1000000 is a Sun convention for 224 * "set to current server time". It's needed to make permissions checks 225 * for the "touch" program across v2 mounts to Solaris and Irix servers 226 * work correctly. See description of sattr in section 6.1 of "NFS 227 * Illustrated" by Brent Callaghan, Addison-Wesley, ISBN 0-201-32750-5. 228 */ 229 static __be32 *xdr_encode_current_server_time(__be32 *p, 230 const struct timespec *timep) 231 { 232 *p++ = cpu_to_be32(timep->tv_sec); 233 *p++ = cpu_to_be32(1000000); 234 return p; 235 } 236 237 static __be32 *xdr_decode_time(__be32 *p, struct timespec *timep) 238 { 239 timep->tv_sec = be32_to_cpup(p++); 240 timep->tv_nsec = be32_to_cpup(p++) * NSEC_PER_USEC; 241 return p; 242 } 243 244 /* 245 * 2.3.5. fattr 246 * 247 * struct fattr { 248 * ftype type; 249 * unsigned int mode; 250 * unsigned int nlink; 251 * unsigned int uid; 252 * unsigned int gid; 253 * unsigned int size; 254 * unsigned int blocksize; 255 * unsigned int rdev; 256 * unsigned int blocks; 257 * unsigned int fsid; 258 * unsigned int fileid; 259 * timeval atime; 260 * timeval mtime; 261 * timeval ctime; 262 * }; 263 * 264 */ 265 static int decode_fattr(struct xdr_stream *xdr, struct nfs_fattr *fattr, 266 struct user_namespace *userns) 267 { 268 u32 rdev, type; 269 __be32 *p; 270 271 p = xdr_inline_decode(xdr, NFS_fattr_sz << 2); 272 if (unlikely(!p)) 273 return -EIO; 274 275 fattr->valid |= NFS_ATTR_FATTR_V2; 276 277 p = xdr_decode_ftype(p, &type); 278 279 fattr->mode = be32_to_cpup(p++); 280 fattr->nlink = be32_to_cpup(p++); 281 fattr->uid = make_kuid(userns, be32_to_cpup(p++)); 282 if (!uid_valid(fattr->uid)) 283 goto out_uid; 284 fattr->gid = make_kgid(userns, be32_to_cpup(p++)); 285 if (!gid_valid(fattr->gid)) 286 goto out_gid; 287 288 fattr->size = be32_to_cpup(p++); 289 fattr->du.nfs2.blocksize = be32_to_cpup(p++); 290 291 rdev = be32_to_cpup(p++); 292 fattr->rdev = new_decode_dev(rdev); 293 if (type == (u32)NFCHR && rdev == (u32)NFS2_FIFO_DEV) { 294 fattr->mode = (fattr->mode & ~S_IFMT) | S_IFIFO; 295 fattr->rdev = 0; 296 } 297 298 fattr->du.nfs2.blocks = be32_to_cpup(p++); 299 fattr->fsid.major = be32_to_cpup(p++); 300 fattr->fsid.minor = 0; 301 fattr->fileid = be32_to_cpup(p++); 302 303 p = xdr_decode_time(p, &fattr->atime); 304 p = xdr_decode_time(p, &fattr->mtime); 305 xdr_decode_time(p, &fattr->ctime); 306 fattr->change_attr = nfs_timespec_to_change_attr(&fattr->ctime); 307 308 return 0; 309 out_uid: 310 dprintk("NFS: returned invalid uid\n"); 311 return -EINVAL; 312 out_gid: 313 dprintk("NFS: returned invalid gid\n"); 314 return -EINVAL; 315 } 316 317 /* 318 * 2.3.6. sattr 319 * 320 * struct sattr { 321 * unsigned int mode; 322 * unsigned int uid; 323 * unsigned int gid; 324 * unsigned int size; 325 * timeval atime; 326 * timeval mtime; 327 * }; 328 */ 329 330 #define NFS2_SATTR_NOT_SET (0xffffffff) 331 332 static __be32 *xdr_time_not_set(__be32 *p) 333 { 334 *p++ = cpu_to_be32(NFS2_SATTR_NOT_SET); 335 *p++ = cpu_to_be32(NFS2_SATTR_NOT_SET); 336 return p; 337 } 338 339 static void encode_sattr(struct xdr_stream *xdr, const struct iattr *attr, 340 struct user_namespace *userns) 341 { 342 struct timespec ts; 343 __be32 *p; 344 345 p = xdr_reserve_space(xdr, NFS_sattr_sz << 2); 346 347 if (attr->ia_valid & ATTR_MODE) 348 *p++ = cpu_to_be32(attr->ia_mode); 349 else 350 *p++ = cpu_to_be32(NFS2_SATTR_NOT_SET); 351 if (attr->ia_valid & ATTR_UID) 352 *p++ = cpu_to_be32(from_kuid_munged(userns, attr->ia_uid)); 353 else 354 *p++ = cpu_to_be32(NFS2_SATTR_NOT_SET); 355 if (attr->ia_valid & ATTR_GID) 356 *p++ = cpu_to_be32(from_kgid_munged(userns, attr->ia_gid)); 357 else 358 *p++ = cpu_to_be32(NFS2_SATTR_NOT_SET); 359 if (attr->ia_valid & ATTR_SIZE) 360 *p++ = cpu_to_be32((u32)attr->ia_size); 361 else 362 *p++ = cpu_to_be32(NFS2_SATTR_NOT_SET); 363 364 if (attr->ia_valid & ATTR_ATIME_SET) { 365 ts = timespec64_to_timespec(attr->ia_atime); 366 p = xdr_encode_time(p, &ts); 367 } else if (attr->ia_valid & ATTR_ATIME) { 368 ts = timespec64_to_timespec(attr->ia_atime); 369 p = xdr_encode_current_server_time(p, &ts); 370 } else 371 p = xdr_time_not_set(p); 372 if (attr->ia_valid & ATTR_MTIME_SET) { 373 ts = timespec64_to_timespec(attr->ia_atime); 374 xdr_encode_time(p, &ts); 375 } else if (attr->ia_valid & ATTR_MTIME) { 376 ts = timespec64_to_timespec(attr->ia_mtime); 377 xdr_encode_current_server_time(p, &ts); 378 } else 379 xdr_time_not_set(p); 380 } 381 382 /* 383 * 2.3.7. filename 384 * 385 * typedef string filename<MAXNAMLEN>; 386 */ 387 static void encode_filename(struct xdr_stream *xdr, 388 const char *name, u32 length) 389 { 390 __be32 *p; 391 392 WARN_ON_ONCE(length > NFS2_MAXNAMLEN); 393 p = xdr_reserve_space(xdr, 4 + length); 394 xdr_encode_opaque(p, name, length); 395 } 396 397 static int decode_filename_inline(struct xdr_stream *xdr, 398 const char **name, u32 *length) 399 { 400 __be32 *p; 401 u32 count; 402 403 p = xdr_inline_decode(xdr, 4); 404 if (unlikely(!p)) 405 return -EIO; 406 count = be32_to_cpup(p); 407 if (count > NFS3_MAXNAMLEN) 408 goto out_nametoolong; 409 p = xdr_inline_decode(xdr, count); 410 if (unlikely(!p)) 411 return -EIO; 412 *name = (const char *)p; 413 *length = count; 414 return 0; 415 out_nametoolong: 416 dprintk("NFS: returned filename too long: %u\n", count); 417 return -ENAMETOOLONG; 418 } 419 420 /* 421 * 2.3.8. path 422 * 423 * typedef string path<MAXPATHLEN>; 424 */ 425 static void encode_path(struct xdr_stream *xdr, struct page **pages, u32 length) 426 { 427 __be32 *p; 428 429 p = xdr_reserve_space(xdr, 4); 430 *p = cpu_to_be32(length); 431 xdr_write_pages(xdr, pages, 0, length); 432 } 433 434 static int decode_path(struct xdr_stream *xdr) 435 { 436 u32 length, recvd; 437 __be32 *p; 438 439 p = xdr_inline_decode(xdr, 4); 440 if (unlikely(!p)) 441 return -EIO; 442 length = be32_to_cpup(p); 443 if (unlikely(length >= xdr->buf->page_len || length > NFS_MAXPATHLEN)) 444 goto out_size; 445 recvd = xdr_read_pages(xdr, length); 446 if (unlikely(length > recvd)) 447 goto out_cheating; 448 xdr_terminate_string(xdr->buf, length); 449 return 0; 450 out_size: 451 dprintk("NFS: returned pathname too long: %u\n", length); 452 return -ENAMETOOLONG; 453 out_cheating: 454 dprintk("NFS: server cheating in pathname result: " 455 "length %u > received %u\n", length, recvd); 456 return -EIO; 457 } 458 459 /* 460 * 2.3.9. attrstat 461 * 462 * union attrstat switch (stat status) { 463 * case NFS_OK: 464 * fattr attributes; 465 * default: 466 * void; 467 * }; 468 */ 469 static int decode_attrstat(struct xdr_stream *xdr, struct nfs_fattr *result, 470 __u32 *op_status, 471 struct user_namespace *userns) 472 { 473 enum nfs_stat status; 474 int error; 475 476 error = decode_stat(xdr, &status); 477 if (unlikely(error)) 478 goto out; 479 if (op_status) 480 *op_status = status; 481 if (status != NFS_OK) 482 goto out_default; 483 error = decode_fattr(xdr, result, userns); 484 out: 485 return error; 486 out_default: 487 return nfs_stat_to_errno(status); 488 } 489 490 /* 491 * 2.3.10. diropargs 492 * 493 * struct diropargs { 494 * fhandle dir; 495 * filename name; 496 * }; 497 */ 498 static void encode_diropargs(struct xdr_stream *xdr, const struct nfs_fh *fh, 499 const char *name, u32 length) 500 { 501 encode_fhandle(xdr, fh); 502 encode_filename(xdr, name, length); 503 } 504 505 /* 506 * 2.3.11. diropres 507 * 508 * union diropres switch (stat status) { 509 * case NFS_OK: 510 * struct { 511 * fhandle file; 512 * fattr attributes; 513 * } diropok; 514 * default: 515 * void; 516 * }; 517 */ 518 static int decode_diropok(struct xdr_stream *xdr, struct nfs_diropok *result, 519 struct user_namespace *userns) 520 { 521 int error; 522 523 error = decode_fhandle(xdr, result->fh); 524 if (unlikely(error)) 525 goto out; 526 error = decode_fattr(xdr, result->fattr, userns); 527 out: 528 return error; 529 } 530 531 static int decode_diropres(struct xdr_stream *xdr, struct nfs_diropok *result, 532 struct user_namespace *userns) 533 { 534 enum nfs_stat status; 535 int error; 536 537 error = decode_stat(xdr, &status); 538 if (unlikely(error)) 539 goto out; 540 if (status != NFS_OK) 541 goto out_default; 542 error = decode_diropok(xdr, result, userns); 543 out: 544 return error; 545 out_default: 546 return nfs_stat_to_errno(status); 547 } 548 549 550 /* 551 * NFSv2 XDR encode functions 552 * 553 * NFSv2 argument types are defined in section 2.2 of RFC 1094: 554 * "NFS: Network File System Protocol Specification". 555 */ 556 557 static void nfs2_xdr_enc_fhandle(struct rpc_rqst *req, 558 struct xdr_stream *xdr, 559 const void *data) 560 { 561 const struct nfs_fh *fh = data; 562 563 encode_fhandle(xdr, fh); 564 } 565 566 /* 567 * 2.2.3. sattrargs 568 * 569 * struct sattrargs { 570 * fhandle file; 571 * sattr attributes; 572 * }; 573 */ 574 static void nfs2_xdr_enc_sattrargs(struct rpc_rqst *req, 575 struct xdr_stream *xdr, 576 const void *data) 577 { 578 const struct nfs_sattrargs *args = data; 579 580 encode_fhandle(xdr, args->fh); 581 encode_sattr(xdr, args->sattr, rpc_rqst_userns(req)); 582 } 583 584 static void nfs2_xdr_enc_diropargs(struct rpc_rqst *req, 585 struct xdr_stream *xdr, 586 const void *data) 587 { 588 const struct nfs_diropargs *args = data; 589 590 encode_diropargs(xdr, args->fh, args->name, args->len); 591 } 592 593 static void nfs2_xdr_enc_readlinkargs(struct rpc_rqst *req, 594 struct xdr_stream *xdr, 595 const void *data) 596 { 597 const struct nfs_readlinkargs *args = data; 598 599 encode_fhandle(xdr, args->fh); 600 rpc_prepare_reply_pages(req, args->pages, args->pgbase, 601 args->pglen, NFS_readlinkres_sz); 602 } 603 604 /* 605 * 2.2.7. readargs 606 * 607 * struct readargs { 608 * fhandle file; 609 * unsigned offset; 610 * unsigned count; 611 * unsigned totalcount; 612 * }; 613 */ 614 static void encode_readargs(struct xdr_stream *xdr, 615 const struct nfs_pgio_args *args) 616 { 617 u32 offset = args->offset; 618 u32 count = args->count; 619 __be32 *p; 620 621 encode_fhandle(xdr, args->fh); 622 623 p = xdr_reserve_space(xdr, 4 + 4 + 4); 624 *p++ = cpu_to_be32(offset); 625 *p++ = cpu_to_be32(count); 626 *p = cpu_to_be32(count); 627 } 628 629 static void nfs2_xdr_enc_readargs(struct rpc_rqst *req, 630 struct xdr_stream *xdr, 631 const void *data) 632 { 633 const struct nfs_pgio_args *args = data; 634 635 encode_readargs(xdr, args); 636 rpc_prepare_reply_pages(req, args->pages, args->pgbase, 637 args->count, NFS_readres_sz); 638 req->rq_rcv_buf.flags |= XDRBUF_READ; 639 } 640 641 /* 642 * 2.2.9. writeargs 643 * 644 * struct writeargs { 645 * fhandle file; 646 * unsigned beginoffset; 647 * unsigned offset; 648 * unsigned totalcount; 649 * nfsdata data; 650 * }; 651 */ 652 static void encode_writeargs(struct xdr_stream *xdr, 653 const struct nfs_pgio_args *args) 654 { 655 u32 offset = args->offset; 656 u32 count = args->count; 657 __be32 *p; 658 659 encode_fhandle(xdr, args->fh); 660 661 p = xdr_reserve_space(xdr, 4 + 4 + 4 + 4); 662 *p++ = cpu_to_be32(offset); 663 *p++ = cpu_to_be32(offset); 664 *p++ = cpu_to_be32(count); 665 666 /* nfsdata */ 667 *p = cpu_to_be32(count); 668 xdr_write_pages(xdr, args->pages, args->pgbase, count); 669 } 670 671 static void nfs2_xdr_enc_writeargs(struct rpc_rqst *req, 672 struct xdr_stream *xdr, 673 const void *data) 674 { 675 const struct nfs_pgio_args *args = data; 676 677 encode_writeargs(xdr, args); 678 xdr->buf->flags |= XDRBUF_WRITE; 679 } 680 681 /* 682 * 2.2.10. createargs 683 * 684 * struct createargs { 685 * diropargs where; 686 * sattr attributes; 687 * }; 688 */ 689 static void nfs2_xdr_enc_createargs(struct rpc_rqst *req, 690 struct xdr_stream *xdr, 691 const void *data) 692 { 693 const struct nfs_createargs *args = data; 694 695 encode_diropargs(xdr, args->fh, args->name, args->len); 696 encode_sattr(xdr, args->sattr, rpc_rqst_userns(req)); 697 } 698 699 static void nfs2_xdr_enc_removeargs(struct rpc_rqst *req, 700 struct xdr_stream *xdr, 701 const void *data) 702 { 703 const struct nfs_removeargs *args = data; 704 705 encode_diropargs(xdr, args->fh, args->name.name, args->name.len); 706 } 707 708 /* 709 * 2.2.12. renameargs 710 * 711 * struct renameargs { 712 * diropargs from; 713 * diropargs to; 714 * }; 715 */ 716 static void nfs2_xdr_enc_renameargs(struct rpc_rqst *req, 717 struct xdr_stream *xdr, 718 const void *data) 719 { 720 const struct nfs_renameargs *args = data; 721 const struct qstr *old = args->old_name; 722 const struct qstr *new = args->new_name; 723 724 encode_diropargs(xdr, args->old_dir, old->name, old->len); 725 encode_diropargs(xdr, args->new_dir, new->name, new->len); 726 } 727 728 /* 729 * 2.2.13. linkargs 730 * 731 * struct linkargs { 732 * fhandle from; 733 * diropargs to; 734 * }; 735 */ 736 static void nfs2_xdr_enc_linkargs(struct rpc_rqst *req, 737 struct xdr_stream *xdr, 738 const void *data) 739 { 740 const struct nfs_linkargs *args = data; 741 742 encode_fhandle(xdr, args->fromfh); 743 encode_diropargs(xdr, args->tofh, args->toname, args->tolen); 744 } 745 746 /* 747 * 2.2.14. symlinkargs 748 * 749 * struct symlinkargs { 750 * diropargs from; 751 * path to; 752 * sattr attributes; 753 * }; 754 */ 755 static void nfs2_xdr_enc_symlinkargs(struct rpc_rqst *req, 756 struct xdr_stream *xdr, 757 const void *data) 758 { 759 const struct nfs_symlinkargs *args = data; 760 761 encode_diropargs(xdr, args->fromfh, args->fromname, args->fromlen); 762 encode_path(xdr, args->pages, args->pathlen); 763 encode_sattr(xdr, args->sattr, rpc_rqst_userns(req)); 764 } 765 766 /* 767 * 2.2.17. readdirargs 768 * 769 * struct readdirargs { 770 * fhandle dir; 771 * nfscookie cookie; 772 * unsigned count; 773 * }; 774 */ 775 static void encode_readdirargs(struct xdr_stream *xdr, 776 const struct nfs_readdirargs *args) 777 { 778 __be32 *p; 779 780 encode_fhandle(xdr, args->fh); 781 782 p = xdr_reserve_space(xdr, 4 + 4); 783 *p++ = cpu_to_be32(args->cookie); 784 *p = cpu_to_be32(args->count); 785 } 786 787 static void nfs2_xdr_enc_readdirargs(struct rpc_rqst *req, 788 struct xdr_stream *xdr, 789 const void *data) 790 { 791 const struct nfs_readdirargs *args = data; 792 793 encode_readdirargs(xdr, args); 794 rpc_prepare_reply_pages(req, args->pages, 0, 795 args->count, NFS_readdirres_sz); 796 } 797 798 /* 799 * NFSv2 XDR decode functions 800 * 801 * NFSv2 result types are defined in section 2.2 of RFC 1094: 802 * "NFS: Network File System Protocol Specification". 803 */ 804 805 static int nfs2_xdr_dec_stat(struct rpc_rqst *req, struct xdr_stream *xdr, 806 void *__unused) 807 { 808 enum nfs_stat status; 809 int error; 810 811 error = decode_stat(xdr, &status); 812 if (unlikely(error)) 813 goto out; 814 if (status != NFS_OK) 815 goto out_default; 816 out: 817 return error; 818 out_default: 819 return nfs_stat_to_errno(status); 820 } 821 822 static int nfs2_xdr_dec_attrstat(struct rpc_rqst *req, struct xdr_stream *xdr, 823 void *result) 824 { 825 return decode_attrstat(xdr, result, NULL, rpc_rqst_userns(req)); 826 } 827 828 static int nfs2_xdr_dec_diropres(struct rpc_rqst *req, struct xdr_stream *xdr, 829 void *result) 830 { 831 return decode_diropres(xdr, result, rpc_rqst_userns(req)); 832 } 833 834 /* 835 * 2.2.6. readlinkres 836 * 837 * union readlinkres switch (stat status) { 838 * case NFS_OK: 839 * path data; 840 * default: 841 * void; 842 * }; 843 */ 844 static int nfs2_xdr_dec_readlinkres(struct rpc_rqst *req, 845 struct xdr_stream *xdr, void *__unused) 846 { 847 enum nfs_stat status; 848 int error; 849 850 error = decode_stat(xdr, &status); 851 if (unlikely(error)) 852 goto out; 853 if (status != NFS_OK) 854 goto out_default; 855 error = decode_path(xdr); 856 out: 857 return error; 858 out_default: 859 return nfs_stat_to_errno(status); 860 } 861 862 /* 863 * 2.2.7. readres 864 * 865 * union readres switch (stat status) { 866 * case NFS_OK: 867 * fattr attributes; 868 * nfsdata data; 869 * default: 870 * void; 871 * }; 872 */ 873 static int nfs2_xdr_dec_readres(struct rpc_rqst *req, struct xdr_stream *xdr, 874 void *data) 875 { 876 struct nfs_pgio_res *result = data; 877 enum nfs_stat status; 878 int error; 879 880 error = decode_stat(xdr, &status); 881 if (unlikely(error)) 882 goto out; 883 result->op_status = status; 884 if (status != NFS_OK) 885 goto out_default; 886 error = decode_fattr(xdr, result->fattr, rpc_rqst_userns(req)); 887 if (unlikely(error)) 888 goto out; 889 error = decode_nfsdata(xdr, result); 890 out: 891 return error; 892 out_default: 893 return nfs_stat_to_errno(status); 894 } 895 896 static int nfs2_xdr_dec_writeres(struct rpc_rqst *req, struct xdr_stream *xdr, 897 void *data) 898 { 899 struct nfs_pgio_res *result = data; 900 901 /* All NFSv2 writes are "file sync" writes */ 902 result->verf->committed = NFS_FILE_SYNC; 903 return decode_attrstat(xdr, result->fattr, &result->op_status, 904 rpc_rqst_userns(req)); 905 } 906 907 /** 908 * nfs2_decode_dirent - Decode a single NFSv2 directory entry stored in 909 * the local page cache. 910 * @xdr: XDR stream where entry resides 911 * @entry: buffer to fill in with entry data 912 * @plus: boolean indicating whether this should be a readdirplus entry 913 * 914 * Returns zero if successful, otherwise a negative errno value is 915 * returned. 916 * 917 * This function is not invoked during READDIR reply decoding, but 918 * rather whenever an application invokes the getdents(2) system call 919 * on a directory already in our cache. 920 * 921 * 2.2.17. entry 922 * 923 * struct entry { 924 * unsigned fileid; 925 * filename name; 926 * nfscookie cookie; 927 * entry *nextentry; 928 * }; 929 */ 930 int nfs2_decode_dirent(struct xdr_stream *xdr, struct nfs_entry *entry, 931 bool plus) 932 { 933 __be32 *p; 934 int error; 935 936 p = xdr_inline_decode(xdr, 4); 937 if (unlikely(!p)) 938 return -EAGAIN; 939 if (*p++ == xdr_zero) { 940 p = xdr_inline_decode(xdr, 4); 941 if (unlikely(!p)) 942 return -EAGAIN; 943 if (*p++ == xdr_zero) 944 return -EAGAIN; 945 entry->eof = 1; 946 return -EBADCOOKIE; 947 } 948 949 p = xdr_inline_decode(xdr, 4); 950 if (unlikely(!p)) 951 return -EAGAIN; 952 entry->ino = be32_to_cpup(p); 953 954 error = decode_filename_inline(xdr, &entry->name, &entry->len); 955 if (unlikely(error)) 956 return error; 957 958 /* 959 * The type (size and byte order) of nfscookie isn't defined in 960 * RFC 1094. This implementation assumes that it's an XDR uint32. 961 */ 962 entry->prev_cookie = entry->cookie; 963 p = xdr_inline_decode(xdr, 4); 964 if (unlikely(!p)) 965 return -EAGAIN; 966 entry->cookie = be32_to_cpup(p); 967 968 entry->d_type = DT_UNKNOWN; 969 970 return 0; 971 } 972 973 /* 974 * 2.2.17. readdirres 975 * 976 * union readdirres switch (stat status) { 977 * case NFS_OK: 978 * struct { 979 * entry *entries; 980 * bool eof; 981 * } readdirok; 982 * default: 983 * void; 984 * }; 985 * 986 * Read the directory contents into the page cache, but don't 987 * touch them. The actual decoding is done by nfs2_decode_dirent() 988 * during subsequent nfs_readdir() calls. 989 */ 990 static int decode_readdirok(struct xdr_stream *xdr) 991 { 992 return xdr_read_pages(xdr, xdr->buf->page_len); 993 } 994 995 static int nfs2_xdr_dec_readdirres(struct rpc_rqst *req, 996 struct xdr_stream *xdr, void *__unused) 997 { 998 enum nfs_stat status; 999 int error; 1000 1001 error = decode_stat(xdr, &status); 1002 if (unlikely(error)) 1003 goto out; 1004 if (status != NFS_OK) 1005 goto out_default; 1006 error = decode_readdirok(xdr); 1007 out: 1008 return error; 1009 out_default: 1010 return nfs_stat_to_errno(status); 1011 } 1012 1013 /* 1014 * 2.2.18. statfsres 1015 * 1016 * union statfsres (stat status) { 1017 * case NFS_OK: 1018 * struct { 1019 * unsigned tsize; 1020 * unsigned bsize; 1021 * unsigned blocks; 1022 * unsigned bfree; 1023 * unsigned bavail; 1024 * } info; 1025 * default: 1026 * void; 1027 * }; 1028 */ 1029 static int decode_info(struct xdr_stream *xdr, struct nfs2_fsstat *result) 1030 { 1031 __be32 *p; 1032 1033 p = xdr_inline_decode(xdr, NFS_info_sz << 2); 1034 if (unlikely(!p)) 1035 return -EIO; 1036 result->tsize = be32_to_cpup(p++); 1037 result->bsize = be32_to_cpup(p++); 1038 result->blocks = be32_to_cpup(p++); 1039 result->bfree = be32_to_cpup(p++); 1040 result->bavail = be32_to_cpup(p); 1041 return 0; 1042 } 1043 1044 static int nfs2_xdr_dec_statfsres(struct rpc_rqst *req, struct xdr_stream *xdr, 1045 void *result) 1046 { 1047 enum nfs_stat status; 1048 int error; 1049 1050 error = decode_stat(xdr, &status); 1051 if (unlikely(error)) 1052 goto out; 1053 if (status != NFS_OK) 1054 goto out_default; 1055 error = decode_info(xdr, result); 1056 out: 1057 return error; 1058 out_default: 1059 return nfs_stat_to_errno(status); 1060 } 1061 1062 1063 /* 1064 * We need to translate between nfs status return values and 1065 * the local errno values which may not be the same. 1066 */ 1067 static const struct { 1068 int stat; 1069 int errno; 1070 } nfs_errtbl[] = { 1071 { NFS_OK, 0 }, 1072 { NFSERR_PERM, -EPERM }, 1073 { NFSERR_NOENT, -ENOENT }, 1074 { NFSERR_IO, -errno_NFSERR_IO}, 1075 { NFSERR_NXIO, -ENXIO }, 1076 /* { NFSERR_EAGAIN, -EAGAIN }, */ 1077 { NFSERR_ACCES, -EACCES }, 1078 { NFSERR_EXIST, -EEXIST }, 1079 { NFSERR_XDEV, -EXDEV }, 1080 { NFSERR_NODEV, -ENODEV }, 1081 { NFSERR_NOTDIR, -ENOTDIR }, 1082 { NFSERR_ISDIR, -EISDIR }, 1083 { NFSERR_INVAL, -EINVAL }, 1084 { NFSERR_FBIG, -EFBIG }, 1085 { NFSERR_NOSPC, -ENOSPC }, 1086 { NFSERR_ROFS, -EROFS }, 1087 { NFSERR_MLINK, -EMLINK }, 1088 { NFSERR_NAMETOOLONG, -ENAMETOOLONG }, 1089 { NFSERR_NOTEMPTY, -ENOTEMPTY }, 1090 { NFSERR_DQUOT, -EDQUOT }, 1091 { NFSERR_STALE, -ESTALE }, 1092 { NFSERR_REMOTE, -EREMOTE }, 1093 #ifdef EWFLUSH 1094 { NFSERR_WFLUSH, -EWFLUSH }, 1095 #endif 1096 { NFSERR_BADHANDLE, -EBADHANDLE }, 1097 { NFSERR_NOT_SYNC, -ENOTSYNC }, 1098 { NFSERR_BAD_COOKIE, -EBADCOOKIE }, 1099 { NFSERR_NOTSUPP, -ENOTSUPP }, 1100 { NFSERR_TOOSMALL, -ETOOSMALL }, 1101 { NFSERR_SERVERFAULT, -EREMOTEIO }, 1102 { NFSERR_BADTYPE, -EBADTYPE }, 1103 { NFSERR_JUKEBOX, -EJUKEBOX }, 1104 { -1, -EIO } 1105 }; 1106 1107 /** 1108 * nfs_stat_to_errno - convert an NFS status code to a local errno 1109 * @status: NFS status code to convert 1110 * 1111 * Returns a local errno value, or -EIO if the NFS status code is 1112 * not recognized. This function is used jointly by NFSv2 and NFSv3. 1113 */ 1114 static int nfs_stat_to_errno(enum nfs_stat status) 1115 { 1116 int i; 1117 1118 for (i = 0; nfs_errtbl[i].stat != -1; i++) { 1119 if (nfs_errtbl[i].stat == (int)status) 1120 return nfs_errtbl[i].errno; 1121 } 1122 dprintk("NFS: Unrecognized nfs status value: %u\n", status); 1123 return nfs_errtbl[i].errno; 1124 } 1125 1126 #define PROC(proc, argtype, restype, timer) \ 1127 [NFSPROC_##proc] = { \ 1128 .p_proc = NFSPROC_##proc, \ 1129 .p_encode = nfs2_xdr_enc_##argtype, \ 1130 .p_decode = nfs2_xdr_dec_##restype, \ 1131 .p_arglen = NFS_##argtype##_sz, \ 1132 .p_replen = NFS_##restype##_sz, \ 1133 .p_timer = timer, \ 1134 .p_statidx = NFSPROC_##proc, \ 1135 .p_name = #proc, \ 1136 } 1137 const struct rpc_procinfo nfs_procedures[] = { 1138 PROC(GETATTR, fhandle, attrstat, 1), 1139 PROC(SETATTR, sattrargs, attrstat, 0), 1140 PROC(LOOKUP, diropargs, diropres, 2), 1141 PROC(READLINK, readlinkargs, readlinkres, 3), 1142 PROC(READ, readargs, readres, 3), 1143 PROC(WRITE, writeargs, writeres, 4), 1144 PROC(CREATE, createargs, diropres, 0), 1145 PROC(REMOVE, removeargs, stat, 0), 1146 PROC(RENAME, renameargs, stat, 0), 1147 PROC(LINK, linkargs, stat, 0), 1148 PROC(SYMLINK, symlinkargs, stat, 0), 1149 PROC(MKDIR, createargs, diropres, 0), 1150 PROC(RMDIR, diropargs, stat, 0), 1151 PROC(READDIR, readdirargs, readdirres, 3), 1152 PROC(STATFS, fhandle, statfsres, 0), 1153 }; 1154 1155 static unsigned int nfs_version2_counts[ARRAY_SIZE(nfs_procedures)]; 1156 const struct rpc_version nfs_version2 = { 1157 .number = 2, 1158 .nrprocs = ARRAY_SIZE(nfs_procedures), 1159 .procs = nfs_procedures, 1160 .counts = nfs_version2_counts, 1161 }; 1162