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