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(xdr, (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 timespec64 *timep) 213 { 214 *p++ = cpu_to_be32((u32)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 timespec64 *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 timespec64 *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 __be32 *p; 343 344 p = xdr_reserve_space(xdr, NFS_sattr_sz << 2); 345 346 if (attr->ia_valid & ATTR_MODE) 347 *p++ = cpu_to_be32(attr->ia_mode); 348 else 349 *p++ = cpu_to_be32(NFS2_SATTR_NOT_SET); 350 if (attr->ia_valid & ATTR_UID) 351 *p++ = cpu_to_be32(from_kuid_munged(userns, attr->ia_uid)); 352 else 353 *p++ = cpu_to_be32(NFS2_SATTR_NOT_SET); 354 if (attr->ia_valid & ATTR_GID) 355 *p++ = cpu_to_be32(from_kgid_munged(userns, attr->ia_gid)); 356 else 357 *p++ = cpu_to_be32(NFS2_SATTR_NOT_SET); 358 if (attr->ia_valid & ATTR_SIZE) 359 *p++ = cpu_to_be32((u32)attr->ia_size); 360 else 361 *p++ = cpu_to_be32(NFS2_SATTR_NOT_SET); 362 363 if (attr->ia_valid & ATTR_ATIME_SET) { 364 p = xdr_encode_time(p, &attr->ia_atime); 365 } else if (attr->ia_valid & ATTR_ATIME) { 366 p = xdr_encode_current_server_time(p, &attr->ia_atime); 367 } else 368 p = xdr_time_not_set(p); 369 if (attr->ia_valid & ATTR_MTIME_SET) { 370 xdr_encode_time(p, &attr->ia_mtime); 371 } else if (attr->ia_valid & ATTR_MTIME) { 372 xdr_encode_current_server_time(p, &attr->ia_mtime); 373 } else 374 xdr_time_not_set(p); 375 } 376 377 /* 378 * 2.3.7. filename 379 * 380 * typedef string filename<MAXNAMLEN>; 381 */ 382 static void encode_filename(struct xdr_stream *xdr, 383 const char *name, u32 length) 384 { 385 __be32 *p; 386 387 WARN_ON_ONCE(length > NFS2_MAXNAMLEN); 388 p = xdr_reserve_space(xdr, 4 + length); 389 xdr_encode_opaque(p, name, length); 390 } 391 392 static int decode_filename_inline(struct xdr_stream *xdr, 393 const char **name, u32 *length) 394 { 395 __be32 *p; 396 u32 count; 397 398 p = xdr_inline_decode(xdr, 4); 399 if (unlikely(!p)) 400 return -EIO; 401 count = be32_to_cpup(p); 402 if (count > NFS3_MAXNAMLEN) 403 goto out_nametoolong; 404 p = xdr_inline_decode(xdr, count); 405 if (unlikely(!p)) 406 return -EIO; 407 *name = (const char *)p; 408 *length = count; 409 return 0; 410 out_nametoolong: 411 dprintk("NFS: returned filename too long: %u\n", count); 412 return -ENAMETOOLONG; 413 } 414 415 /* 416 * 2.3.8. path 417 * 418 * typedef string path<MAXPATHLEN>; 419 */ 420 static void encode_path(struct xdr_stream *xdr, struct page **pages, u32 length) 421 { 422 __be32 *p; 423 424 p = xdr_reserve_space(xdr, 4); 425 *p = cpu_to_be32(length); 426 xdr_write_pages(xdr, pages, 0, length); 427 } 428 429 static int decode_path(struct xdr_stream *xdr) 430 { 431 u32 length, recvd; 432 __be32 *p; 433 434 p = xdr_inline_decode(xdr, 4); 435 if (unlikely(!p)) 436 return -EIO; 437 length = be32_to_cpup(p); 438 if (unlikely(length >= xdr->buf->page_len || length > NFS_MAXPATHLEN)) 439 goto out_size; 440 recvd = xdr_read_pages(xdr, length); 441 if (unlikely(length > recvd)) 442 goto out_cheating; 443 xdr_terminate_string(xdr->buf, length); 444 return 0; 445 out_size: 446 dprintk("NFS: returned pathname too long: %u\n", length); 447 return -ENAMETOOLONG; 448 out_cheating: 449 dprintk("NFS: server cheating in pathname result: " 450 "length %u > received %u\n", length, recvd); 451 return -EIO; 452 } 453 454 /* 455 * 2.3.9. attrstat 456 * 457 * union attrstat switch (stat status) { 458 * case NFS_OK: 459 * fattr attributes; 460 * default: 461 * void; 462 * }; 463 */ 464 static int decode_attrstat(struct xdr_stream *xdr, struct nfs_fattr *result, 465 __u32 *op_status, 466 struct user_namespace *userns) 467 { 468 enum nfs_stat status; 469 int error; 470 471 error = decode_stat(xdr, &status); 472 if (unlikely(error)) 473 goto out; 474 if (op_status) 475 *op_status = status; 476 if (status != NFS_OK) 477 goto out_default; 478 error = decode_fattr(xdr, result, userns); 479 out: 480 return error; 481 out_default: 482 return nfs_stat_to_errno(status); 483 } 484 485 /* 486 * 2.3.10. diropargs 487 * 488 * struct diropargs { 489 * fhandle dir; 490 * filename name; 491 * }; 492 */ 493 static void encode_diropargs(struct xdr_stream *xdr, const struct nfs_fh *fh, 494 const char *name, u32 length) 495 { 496 encode_fhandle(xdr, fh); 497 encode_filename(xdr, name, length); 498 } 499 500 /* 501 * 2.3.11. diropres 502 * 503 * union diropres switch (stat status) { 504 * case NFS_OK: 505 * struct { 506 * fhandle file; 507 * fattr attributes; 508 * } diropok; 509 * default: 510 * void; 511 * }; 512 */ 513 static int decode_diropok(struct xdr_stream *xdr, struct nfs_diropok *result, 514 struct user_namespace *userns) 515 { 516 int error; 517 518 error = decode_fhandle(xdr, result->fh); 519 if (unlikely(error)) 520 goto out; 521 error = decode_fattr(xdr, result->fattr, userns); 522 out: 523 return error; 524 } 525 526 static int decode_diropres(struct xdr_stream *xdr, struct nfs_diropok *result, 527 struct user_namespace *userns) 528 { 529 enum nfs_stat status; 530 int error; 531 532 error = decode_stat(xdr, &status); 533 if (unlikely(error)) 534 goto out; 535 if (status != NFS_OK) 536 goto out_default; 537 error = decode_diropok(xdr, result, userns); 538 out: 539 return error; 540 out_default: 541 return nfs_stat_to_errno(status); 542 } 543 544 545 /* 546 * NFSv2 XDR encode functions 547 * 548 * NFSv2 argument types are defined in section 2.2 of RFC 1094: 549 * "NFS: Network File System Protocol Specification". 550 */ 551 552 static void nfs2_xdr_enc_fhandle(struct rpc_rqst *req, 553 struct xdr_stream *xdr, 554 const void *data) 555 { 556 const struct nfs_fh *fh = data; 557 558 encode_fhandle(xdr, fh); 559 } 560 561 /* 562 * 2.2.3. sattrargs 563 * 564 * struct sattrargs { 565 * fhandle file; 566 * sattr attributes; 567 * }; 568 */ 569 static void nfs2_xdr_enc_sattrargs(struct rpc_rqst *req, 570 struct xdr_stream *xdr, 571 const void *data) 572 { 573 const struct nfs_sattrargs *args = data; 574 575 encode_fhandle(xdr, args->fh); 576 encode_sattr(xdr, args->sattr, rpc_rqst_userns(req)); 577 } 578 579 static void nfs2_xdr_enc_diropargs(struct rpc_rqst *req, 580 struct xdr_stream *xdr, 581 const void *data) 582 { 583 const struct nfs_diropargs *args = data; 584 585 encode_diropargs(xdr, args->fh, args->name, args->len); 586 } 587 588 static void nfs2_xdr_enc_readlinkargs(struct rpc_rqst *req, 589 struct xdr_stream *xdr, 590 const void *data) 591 { 592 const struct nfs_readlinkargs *args = data; 593 594 encode_fhandle(xdr, args->fh); 595 rpc_prepare_reply_pages(req, args->pages, args->pgbase, 596 args->pglen, NFS_readlinkres_sz); 597 } 598 599 /* 600 * 2.2.7. readargs 601 * 602 * struct readargs { 603 * fhandle file; 604 * unsigned offset; 605 * unsigned count; 606 * unsigned totalcount; 607 * }; 608 */ 609 static void encode_readargs(struct xdr_stream *xdr, 610 const struct nfs_pgio_args *args) 611 { 612 u32 offset = args->offset; 613 u32 count = args->count; 614 __be32 *p; 615 616 encode_fhandle(xdr, args->fh); 617 618 p = xdr_reserve_space(xdr, 4 + 4 + 4); 619 *p++ = cpu_to_be32(offset); 620 *p++ = cpu_to_be32(count); 621 *p = cpu_to_be32(count); 622 } 623 624 static void nfs2_xdr_enc_readargs(struct rpc_rqst *req, 625 struct xdr_stream *xdr, 626 const void *data) 627 { 628 const struct nfs_pgio_args *args = data; 629 630 encode_readargs(xdr, args); 631 rpc_prepare_reply_pages(req, args->pages, args->pgbase, 632 args->count, NFS_readres_sz); 633 req->rq_rcv_buf.flags |= XDRBUF_READ; 634 } 635 636 /* 637 * 2.2.9. writeargs 638 * 639 * struct writeargs { 640 * fhandle file; 641 * unsigned beginoffset; 642 * unsigned offset; 643 * unsigned totalcount; 644 * nfsdata data; 645 * }; 646 */ 647 static void encode_writeargs(struct xdr_stream *xdr, 648 const struct nfs_pgio_args *args) 649 { 650 u32 offset = args->offset; 651 u32 count = args->count; 652 __be32 *p; 653 654 encode_fhandle(xdr, args->fh); 655 656 p = xdr_reserve_space(xdr, 4 + 4 + 4 + 4); 657 *p++ = cpu_to_be32(offset); 658 *p++ = cpu_to_be32(offset); 659 *p++ = cpu_to_be32(count); 660 661 /* nfsdata */ 662 *p = cpu_to_be32(count); 663 xdr_write_pages(xdr, args->pages, args->pgbase, count); 664 } 665 666 static void nfs2_xdr_enc_writeargs(struct rpc_rqst *req, 667 struct xdr_stream *xdr, 668 const void *data) 669 { 670 const struct nfs_pgio_args *args = data; 671 672 encode_writeargs(xdr, args); 673 xdr->buf->flags |= XDRBUF_WRITE; 674 } 675 676 /* 677 * 2.2.10. createargs 678 * 679 * struct createargs { 680 * diropargs where; 681 * sattr attributes; 682 * }; 683 */ 684 static void nfs2_xdr_enc_createargs(struct rpc_rqst *req, 685 struct xdr_stream *xdr, 686 const void *data) 687 { 688 const struct nfs_createargs *args = data; 689 690 encode_diropargs(xdr, args->fh, args->name, args->len); 691 encode_sattr(xdr, args->sattr, rpc_rqst_userns(req)); 692 } 693 694 static void nfs2_xdr_enc_removeargs(struct rpc_rqst *req, 695 struct xdr_stream *xdr, 696 const void *data) 697 { 698 const struct nfs_removeargs *args = data; 699 700 encode_diropargs(xdr, args->fh, args->name.name, args->name.len); 701 } 702 703 /* 704 * 2.2.12. renameargs 705 * 706 * struct renameargs { 707 * diropargs from; 708 * diropargs to; 709 * }; 710 */ 711 static void nfs2_xdr_enc_renameargs(struct rpc_rqst *req, 712 struct xdr_stream *xdr, 713 const void *data) 714 { 715 const struct nfs_renameargs *args = data; 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 */ 731 static void nfs2_xdr_enc_linkargs(struct rpc_rqst *req, 732 struct xdr_stream *xdr, 733 const void *data) 734 { 735 const struct nfs_linkargs *args = data; 736 737 encode_fhandle(xdr, args->fromfh); 738 encode_diropargs(xdr, args->tofh, args->toname, args->tolen); 739 } 740 741 /* 742 * 2.2.14. symlinkargs 743 * 744 * struct symlinkargs { 745 * diropargs from; 746 * path to; 747 * sattr attributes; 748 * }; 749 */ 750 static void nfs2_xdr_enc_symlinkargs(struct rpc_rqst *req, 751 struct xdr_stream *xdr, 752 const void *data) 753 { 754 const struct nfs_symlinkargs *args = data; 755 756 encode_diropargs(xdr, args->fromfh, args->fromname, args->fromlen); 757 encode_path(xdr, args->pages, args->pathlen); 758 encode_sattr(xdr, args->sattr, rpc_rqst_userns(req)); 759 } 760 761 /* 762 * 2.2.17. readdirargs 763 * 764 * struct readdirargs { 765 * fhandle dir; 766 * nfscookie cookie; 767 * unsigned count; 768 * }; 769 */ 770 static void encode_readdirargs(struct xdr_stream *xdr, 771 const struct nfs_readdirargs *args) 772 { 773 __be32 *p; 774 775 encode_fhandle(xdr, args->fh); 776 777 p = xdr_reserve_space(xdr, 4 + 4); 778 *p++ = cpu_to_be32(args->cookie); 779 *p = cpu_to_be32(args->count); 780 } 781 782 static void nfs2_xdr_enc_readdirargs(struct rpc_rqst *req, 783 struct xdr_stream *xdr, 784 const void *data) 785 { 786 const struct nfs_readdirargs *args = data; 787 788 encode_readdirargs(xdr, args); 789 rpc_prepare_reply_pages(req, args->pages, 0, 790 args->count, NFS_readdirres_sz); 791 } 792 793 /* 794 * NFSv2 XDR decode functions 795 * 796 * NFSv2 result types are defined in section 2.2 of RFC 1094: 797 * "NFS: Network File System Protocol Specification". 798 */ 799 800 static int nfs2_xdr_dec_stat(struct rpc_rqst *req, struct xdr_stream *xdr, 801 void *__unused) 802 { 803 enum nfs_stat status; 804 int error; 805 806 error = decode_stat(xdr, &status); 807 if (unlikely(error)) 808 goto out; 809 if (status != NFS_OK) 810 goto out_default; 811 out: 812 return error; 813 out_default: 814 return nfs_stat_to_errno(status); 815 } 816 817 static int nfs2_xdr_dec_attrstat(struct rpc_rqst *req, struct xdr_stream *xdr, 818 void *result) 819 { 820 return decode_attrstat(xdr, result, NULL, rpc_rqst_userns(req)); 821 } 822 823 static int nfs2_xdr_dec_diropres(struct rpc_rqst *req, struct xdr_stream *xdr, 824 void *result) 825 { 826 return decode_diropres(xdr, result, rpc_rqst_userns(req)); 827 } 828 829 /* 830 * 2.2.6. readlinkres 831 * 832 * union readlinkres switch (stat status) { 833 * case NFS_OK: 834 * path data; 835 * default: 836 * void; 837 * }; 838 */ 839 static int nfs2_xdr_dec_readlinkres(struct rpc_rqst *req, 840 struct xdr_stream *xdr, void *__unused) 841 { 842 enum nfs_stat status; 843 int error; 844 845 error = decode_stat(xdr, &status); 846 if (unlikely(error)) 847 goto out; 848 if (status != NFS_OK) 849 goto out_default; 850 error = decode_path(xdr); 851 out: 852 return error; 853 out_default: 854 return nfs_stat_to_errno(status); 855 } 856 857 /* 858 * 2.2.7. readres 859 * 860 * union readres switch (stat status) { 861 * case NFS_OK: 862 * fattr attributes; 863 * nfsdata data; 864 * default: 865 * void; 866 * }; 867 */ 868 static int nfs2_xdr_dec_readres(struct rpc_rqst *req, struct xdr_stream *xdr, 869 void *data) 870 { 871 struct nfs_pgio_res *result = data; 872 enum nfs_stat status; 873 int error; 874 875 error = decode_stat(xdr, &status); 876 if (unlikely(error)) 877 goto out; 878 result->op_status = status; 879 if (status != NFS_OK) 880 goto out_default; 881 error = decode_fattr(xdr, result->fattr, rpc_rqst_userns(req)); 882 if (unlikely(error)) 883 goto out; 884 error = decode_nfsdata(xdr, result); 885 out: 886 return error; 887 out_default: 888 return nfs_stat_to_errno(status); 889 } 890 891 static int nfs2_xdr_dec_writeres(struct rpc_rqst *req, struct xdr_stream *xdr, 892 void *data) 893 { 894 struct nfs_pgio_res *result = data; 895 896 /* All NFSv2 writes are "file sync" writes */ 897 result->verf->committed = NFS_FILE_SYNC; 898 return decode_attrstat(xdr, result->fattr, &result->op_status, 899 rpc_rqst_userns(req)); 900 } 901 902 /** 903 * nfs2_decode_dirent - Decode a single NFSv2 directory entry stored in 904 * the local page cache. 905 * @xdr: XDR stream where entry resides 906 * @entry: buffer to fill in with entry data 907 * @plus: boolean indicating whether this should be a readdirplus entry 908 * 909 * Returns zero if successful, otherwise a negative errno value is 910 * returned. 911 * 912 * This function is not invoked during READDIR reply decoding, but 913 * rather whenever an application invokes the getdents(2) system call 914 * on a directory already in our cache. 915 * 916 * 2.2.17. entry 917 * 918 * struct entry { 919 * unsigned fileid; 920 * filename name; 921 * nfscookie cookie; 922 * entry *nextentry; 923 * }; 924 */ 925 int nfs2_decode_dirent(struct xdr_stream *xdr, struct nfs_entry *entry, 926 bool plus) 927 { 928 __be32 *p; 929 int error; 930 931 p = xdr_inline_decode(xdr, 4); 932 if (unlikely(!p)) 933 return -EAGAIN; 934 if (*p++ == xdr_zero) { 935 p = xdr_inline_decode(xdr, 4); 936 if (unlikely(!p)) 937 return -EAGAIN; 938 if (*p++ == xdr_zero) 939 return -EAGAIN; 940 entry->eof = 1; 941 return -EBADCOOKIE; 942 } 943 944 p = xdr_inline_decode(xdr, 4); 945 if (unlikely(!p)) 946 return -EAGAIN; 947 entry->ino = be32_to_cpup(p); 948 949 error = decode_filename_inline(xdr, &entry->name, &entry->len); 950 if (unlikely(error)) 951 return error; 952 953 /* 954 * The type (size and byte order) of nfscookie isn't defined in 955 * RFC 1094. This implementation assumes that it's an XDR uint32. 956 */ 957 entry->prev_cookie = entry->cookie; 958 p = xdr_inline_decode(xdr, 4); 959 if (unlikely(!p)) 960 return -EAGAIN; 961 entry->cookie = be32_to_cpup(p); 962 963 entry->d_type = DT_UNKNOWN; 964 965 return 0; 966 } 967 968 /* 969 * 2.2.17. readdirres 970 * 971 * union readdirres switch (stat status) { 972 * case NFS_OK: 973 * struct { 974 * entry *entries; 975 * bool eof; 976 * } readdirok; 977 * default: 978 * void; 979 * }; 980 * 981 * Read the directory contents into the page cache, but don't 982 * touch them. The actual decoding is done by nfs2_decode_dirent() 983 * during subsequent nfs_readdir() calls. 984 */ 985 static int decode_readdirok(struct xdr_stream *xdr) 986 { 987 return xdr_read_pages(xdr, xdr->buf->page_len); 988 } 989 990 static int nfs2_xdr_dec_readdirres(struct rpc_rqst *req, 991 struct xdr_stream *xdr, void *__unused) 992 { 993 enum nfs_stat status; 994 int error; 995 996 error = decode_stat(xdr, &status); 997 if (unlikely(error)) 998 goto out; 999 if (status != NFS_OK) 1000 goto out_default; 1001 error = decode_readdirok(xdr); 1002 out: 1003 return error; 1004 out_default: 1005 return nfs_stat_to_errno(status); 1006 } 1007 1008 /* 1009 * 2.2.18. statfsres 1010 * 1011 * union statfsres (stat status) { 1012 * case NFS_OK: 1013 * struct { 1014 * unsigned tsize; 1015 * unsigned bsize; 1016 * unsigned blocks; 1017 * unsigned bfree; 1018 * unsigned bavail; 1019 * } info; 1020 * default: 1021 * void; 1022 * }; 1023 */ 1024 static int decode_info(struct xdr_stream *xdr, struct nfs2_fsstat *result) 1025 { 1026 __be32 *p; 1027 1028 p = xdr_inline_decode(xdr, NFS_info_sz << 2); 1029 if (unlikely(!p)) 1030 return -EIO; 1031 result->tsize = be32_to_cpup(p++); 1032 result->bsize = be32_to_cpup(p++); 1033 result->blocks = be32_to_cpup(p++); 1034 result->bfree = be32_to_cpup(p++); 1035 result->bavail = be32_to_cpup(p); 1036 return 0; 1037 } 1038 1039 static int nfs2_xdr_dec_statfsres(struct rpc_rqst *req, struct xdr_stream *xdr, 1040 void *result) 1041 { 1042 enum nfs_stat status; 1043 int error; 1044 1045 error = decode_stat(xdr, &status); 1046 if (unlikely(error)) 1047 goto out; 1048 if (status != NFS_OK) 1049 goto out_default; 1050 error = decode_info(xdr, result); 1051 out: 1052 return error; 1053 out_default: 1054 return nfs_stat_to_errno(status); 1055 } 1056 1057 1058 /* 1059 * We need to translate between nfs status return values and 1060 * the local errno values which may not be the same. 1061 */ 1062 static const struct { 1063 int stat; 1064 int errno; 1065 } nfs_errtbl[] = { 1066 { NFS_OK, 0 }, 1067 { NFSERR_PERM, -EPERM }, 1068 { NFSERR_NOENT, -ENOENT }, 1069 { NFSERR_IO, -errno_NFSERR_IO}, 1070 { NFSERR_NXIO, -ENXIO }, 1071 /* { NFSERR_EAGAIN, -EAGAIN }, */ 1072 { NFSERR_ACCES, -EACCES }, 1073 { NFSERR_EXIST, -EEXIST }, 1074 { NFSERR_XDEV, -EXDEV }, 1075 { NFSERR_NODEV, -ENODEV }, 1076 { NFSERR_NOTDIR, -ENOTDIR }, 1077 { NFSERR_ISDIR, -EISDIR }, 1078 { NFSERR_INVAL, -EINVAL }, 1079 { NFSERR_FBIG, -EFBIG }, 1080 { NFSERR_NOSPC, -ENOSPC }, 1081 { NFSERR_ROFS, -EROFS }, 1082 { NFSERR_MLINK, -EMLINK }, 1083 { NFSERR_NAMETOOLONG, -ENAMETOOLONG }, 1084 { NFSERR_NOTEMPTY, -ENOTEMPTY }, 1085 { NFSERR_DQUOT, -EDQUOT }, 1086 { NFSERR_STALE, -ESTALE }, 1087 { NFSERR_REMOTE, -EREMOTE }, 1088 #ifdef EWFLUSH 1089 { NFSERR_WFLUSH, -EWFLUSH }, 1090 #endif 1091 { NFSERR_BADHANDLE, -EBADHANDLE }, 1092 { NFSERR_NOT_SYNC, -ENOTSYNC }, 1093 { NFSERR_BAD_COOKIE, -EBADCOOKIE }, 1094 { NFSERR_NOTSUPP, -ENOTSUPP }, 1095 { NFSERR_TOOSMALL, -ETOOSMALL }, 1096 { NFSERR_SERVERFAULT, -EREMOTEIO }, 1097 { NFSERR_BADTYPE, -EBADTYPE }, 1098 { NFSERR_JUKEBOX, -EJUKEBOX }, 1099 { -1, -EIO } 1100 }; 1101 1102 /** 1103 * nfs_stat_to_errno - convert an NFS status code to a local errno 1104 * @status: NFS status code to convert 1105 * 1106 * Returns a local errno value, or -EIO if the NFS status code is 1107 * not recognized. This function is used jointly by NFSv2 and NFSv3. 1108 */ 1109 static int nfs_stat_to_errno(enum nfs_stat status) 1110 { 1111 int i; 1112 1113 for (i = 0; nfs_errtbl[i].stat != -1; i++) { 1114 if (nfs_errtbl[i].stat == (int)status) 1115 return nfs_errtbl[i].errno; 1116 } 1117 dprintk("NFS: Unrecognized nfs status value: %u\n", status); 1118 return nfs_errtbl[i].errno; 1119 } 1120 1121 #define PROC(proc, argtype, restype, timer) \ 1122 [NFSPROC_##proc] = { \ 1123 .p_proc = NFSPROC_##proc, \ 1124 .p_encode = nfs2_xdr_enc_##argtype, \ 1125 .p_decode = nfs2_xdr_dec_##restype, \ 1126 .p_arglen = NFS_##argtype##_sz, \ 1127 .p_replen = NFS_##restype##_sz, \ 1128 .p_timer = timer, \ 1129 .p_statidx = NFSPROC_##proc, \ 1130 .p_name = #proc, \ 1131 } 1132 const struct rpc_procinfo nfs_procedures[] = { 1133 PROC(GETATTR, fhandle, attrstat, 1), 1134 PROC(SETATTR, sattrargs, attrstat, 0), 1135 PROC(LOOKUP, diropargs, diropres, 2), 1136 PROC(READLINK, readlinkargs, readlinkres, 3), 1137 PROC(READ, readargs, readres, 3), 1138 PROC(WRITE, writeargs, writeres, 4), 1139 PROC(CREATE, createargs, diropres, 0), 1140 PROC(REMOVE, removeargs, stat, 0), 1141 PROC(RENAME, renameargs, stat, 0), 1142 PROC(LINK, linkargs, stat, 0), 1143 PROC(SYMLINK, symlinkargs, stat, 0), 1144 PROC(MKDIR, createargs, diropres, 0), 1145 PROC(RMDIR, diropargs, stat, 0), 1146 PROC(READDIR, readdirargs, readdirres, 3), 1147 PROC(STATFS, fhandle, statfsres, 0), 1148 }; 1149 1150 static unsigned int nfs_version2_counts[ARRAY_SIZE(nfs_procedures)]; 1151 const struct rpc_version nfs_version2 = { 1152 .number = 2, 1153 .nrprocs = ARRAY_SIZE(nfs_procedures), 1154 .procs = nfs_procedures, 1155 .counts = nfs_version2_counts, 1156 }; 1157