1 /* 2 * In-kernel MOUNT protocol client 3 * 4 * Copyright (C) 1997, Olaf Kirch <okir@monad.swb.de> 5 */ 6 7 #include <linux/types.h> 8 #include <linux/socket.h> 9 #include <linux/kernel.h> 10 #include <linux/errno.h> 11 #include <linux/uio.h> 12 #include <linux/net.h> 13 #include <linux/in.h> 14 #include <linux/sunrpc/clnt.h> 15 #include <linux/sunrpc/sched.h> 16 #include <linux/nfs_fs.h> 17 #include "internal.h" 18 19 #ifdef NFS_DEBUG 20 # define NFSDBG_FACILITY NFSDBG_MOUNT 21 #endif 22 23 /* 24 * Defined by RFC 1094, section A.3; and RFC 1813, section 5.1.4 25 */ 26 #define MNTPATHLEN (1024) 27 28 /* 29 * XDR data type sizes 30 */ 31 #define encode_dirpath_sz (1 + XDR_QUADLEN(MNTPATHLEN)) 32 #define MNT_status_sz (1) 33 #define MNT_fhs_status_sz (1) 34 #define MNT_fhandle_sz XDR_QUADLEN(NFS2_FHSIZE) 35 #define MNT_fhandle3_sz (1 + XDR_QUADLEN(NFS3_FHSIZE)) 36 #define MNT_authflav3_sz (1 + NFS_MAX_SECFLAVORS) 37 38 /* 39 * XDR argument and result sizes 40 */ 41 #define MNT_enc_dirpath_sz encode_dirpath_sz 42 #define MNT_dec_mountres_sz (MNT_status_sz + MNT_fhandle_sz) 43 #define MNT_dec_mountres3_sz (MNT_status_sz + MNT_fhandle_sz + \ 44 MNT_authflav3_sz) 45 46 /* 47 * Defined by RFC 1094, section A.5 48 */ 49 enum { 50 MOUNTPROC_NULL = 0, 51 MOUNTPROC_MNT = 1, 52 MOUNTPROC_DUMP = 2, 53 MOUNTPROC_UMNT = 3, 54 MOUNTPROC_UMNTALL = 4, 55 MOUNTPROC_EXPORT = 5, 56 }; 57 58 /* 59 * Defined by RFC 1813, section 5.2 60 */ 61 enum { 62 MOUNTPROC3_NULL = 0, 63 MOUNTPROC3_MNT = 1, 64 MOUNTPROC3_DUMP = 2, 65 MOUNTPROC3_UMNT = 3, 66 MOUNTPROC3_UMNTALL = 4, 67 MOUNTPROC3_EXPORT = 5, 68 }; 69 70 static const struct rpc_program mnt_program; 71 72 /* 73 * Defined by OpenGroup XNFS Version 3W, chapter 8 74 */ 75 enum mountstat { 76 MNT_OK = 0, 77 MNT_EPERM = 1, 78 MNT_ENOENT = 2, 79 MNT_EACCES = 13, 80 MNT_EINVAL = 22, 81 }; 82 83 static struct { 84 u32 status; 85 int errno; 86 } mnt_errtbl[] = { 87 { .status = MNT_OK, .errno = 0, }, 88 { .status = MNT_EPERM, .errno = -EPERM, }, 89 { .status = MNT_ENOENT, .errno = -ENOENT, }, 90 { .status = MNT_EACCES, .errno = -EACCES, }, 91 { .status = MNT_EINVAL, .errno = -EINVAL, }, 92 }; 93 94 /* 95 * Defined by RFC 1813, section 5.1.5 96 */ 97 enum mountstat3 { 98 MNT3_OK = 0, /* no error */ 99 MNT3ERR_PERM = 1, /* Not owner */ 100 MNT3ERR_NOENT = 2, /* No such file or directory */ 101 MNT3ERR_IO = 5, /* I/O error */ 102 MNT3ERR_ACCES = 13, /* Permission denied */ 103 MNT3ERR_NOTDIR = 20, /* Not a directory */ 104 MNT3ERR_INVAL = 22, /* Invalid argument */ 105 MNT3ERR_NAMETOOLONG = 63, /* Filename too long */ 106 MNT3ERR_NOTSUPP = 10004, /* Operation not supported */ 107 MNT3ERR_SERVERFAULT = 10006, /* A failure on the server */ 108 }; 109 110 static struct { 111 u32 status; 112 int errno; 113 } mnt3_errtbl[] = { 114 { .status = MNT3_OK, .errno = 0, }, 115 { .status = MNT3ERR_PERM, .errno = -EPERM, }, 116 { .status = MNT3ERR_NOENT, .errno = -ENOENT, }, 117 { .status = MNT3ERR_IO, .errno = -EIO, }, 118 { .status = MNT3ERR_ACCES, .errno = -EACCES, }, 119 { .status = MNT3ERR_NOTDIR, .errno = -ENOTDIR, }, 120 { .status = MNT3ERR_INVAL, .errno = -EINVAL, }, 121 { .status = MNT3ERR_NAMETOOLONG, .errno = -ENAMETOOLONG, }, 122 { .status = MNT3ERR_NOTSUPP, .errno = -ENOTSUPP, }, 123 { .status = MNT3ERR_SERVERFAULT, .errno = -EREMOTEIO, }, 124 }; 125 126 struct mountres { 127 int errno; 128 struct nfs_fh *fh; 129 unsigned int *auth_count; 130 rpc_authflavor_t *auth_flavors; 131 }; 132 133 struct mnt_fhstatus { 134 u32 status; 135 struct nfs_fh *fh; 136 }; 137 138 /** 139 * nfs_mount - Obtain an NFS file handle for the given host and path 140 * @info: pointer to mount request arguments 141 * 142 * Uses default timeout parameters specified by underlying transport. On 143 * successful return, the auth_flavs list and auth_flav_len will be populated 144 * with the list from the server or a faked-up list if the server didn't 145 * provide one. 146 */ 147 int nfs_mount(struct nfs_mount_request *info) 148 { 149 struct mountres result = { 150 .fh = info->fh, 151 .auth_count = info->auth_flav_len, 152 .auth_flavors = info->auth_flavs, 153 }; 154 struct rpc_message msg = { 155 .rpc_argp = info->dirpath, 156 .rpc_resp = &result, 157 }; 158 struct rpc_create_args args = { 159 .net = info->net, 160 .protocol = info->protocol, 161 .address = info->sap, 162 .addrsize = info->salen, 163 .servername = info->hostname, 164 .program = &mnt_program, 165 .version = info->version, 166 .authflavor = RPC_AUTH_UNIX, 167 }; 168 struct rpc_clnt *mnt_clnt; 169 int status; 170 171 dprintk("NFS: sending MNT request for %s:%s\n", 172 (info->hostname ? info->hostname : "server"), 173 info->dirpath); 174 175 if (strlen(info->dirpath) > MNTPATHLEN) 176 return -ENAMETOOLONG; 177 178 if (info->noresvport) 179 args.flags |= RPC_CLNT_CREATE_NONPRIVPORT; 180 181 mnt_clnt = rpc_create(&args); 182 if (IS_ERR(mnt_clnt)) 183 goto out_clnt_err; 184 185 if (info->version == NFS_MNT3_VERSION) 186 msg.rpc_proc = &mnt_clnt->cl_procinfo[MOUNTPROC3_MNT]; 187 else 188 msg.rpc_proc = &mnt_clnt->cl_procinfo[MOUNTPROC_MNT]; 189 190 status = rpc_call_sync(mnt_clnt, &msg, RPC_TASK_SOFT|RPC_TASK_TIMEOUT); 191 rpc_shutdown_client(mnt_clnt); 192 193 if (status < 0) 194 goto out_call_err; 195 if (result.errno != 0) 196 goto out_mnt_err; 197 198 dprintk("NFS: MNT request succeeded\n"); 199 status = 0; 200 201 /* 202 * If the server didn't provide a flavor list, allow the 203 * client to try any flavor. 204 */ 205 if (info->version != NFS_MNT3_VERSION || *info->auth_flav_len == 0) { 206 dprintk("NFS: Faking up auth_flavs list\n"); 207 info->auth_flavs[0] = RPC_AUTH_NULL; 208 *info->auth_flav_len = 1; 209 } 210 out: 211 return status; 212 213 out_clnt_err: 214 status = PTR_ERR(mnt_clnt); 215 dprintk("NFS: failed to create MNT RPC client, status=%d\n", status); 216 goto out; 217 218 out_call_err: 219 dprintk("NFS: MNT request failed, status=%d\n", status); 220 goto out; 221 222 out_mnt_err: 223 dprintk("NFS: MNT server returned result %d\n", result.errno); 224 status = result.errno; 225 goto out; 226 } 227 228 /** 229 * nfs_umount - Notify a server that we have unmounted this export 230 * @info: pointer to umount request arguments 231 * 232 * MOUNTPROC_UMNT is advisory, so we set a short timeout, and always 233 * use UDP. 234 */ 235 void nfs_umount(const struct nfs_mount_request *info) 236 { 237 static const struct rpc_timeout nfs_umnt_timeout = { 238 .to_initval = 1 * HZ, 239 .to_maxval = 3 * HZ, 240 .to_retries = 2, 241 }; 242 struct rpc_create_args args = { 243 .net = info->net, 244 .protocol = IPPROTO_UDP, 245 .address = info->sap, 246 .addrsize = info->salen, 247 .timeout = &nfs_umnt_timeout, 248 .servername = info->hostname, 249 .program = &mnt_program, 250 .version = info->version, 251 .authflavor = RPC_AUTH_UNIX, 252 .flags = RPC_CLNT_CREATE_NOPING, 253 }; 254 struct rpc_message msg = { 255 .rpc_argp = info->dirpath, 256 }; 257 struct rpc_clnt *clnt; 258 int status; 259 260 if (strlen(info->dirpath) > MNTPATHLEN) 261 return; 262 263 if (info->noresvport) 264 args.flags |= RPC_CLNT_CREATE_NONPRIVPORT; 265 266 clnt = rpc_create(&args); 267 if (IS_ERR(clnt)) 268 goto out_clnt_err; 269 270 dprintk("NFS: sending UMNT request for %s:%s\n", 271 (info->hostname ? info->hostname : "server"), info->dirpath); 272 273 if (info->version == NFS_MNT3_VERSION) 274 msg.rpc_proc = &clnt->cl_procinfo[MOUNTPROC3_UMNT]; 275 else 276 msg.rpc_proc = &clnt->cl_procinfo[MOUNTPROC_UMNT]; 277 278 status = rpc_call_sync(clnt, &msg, 0); 279 rpc_shutdown_client(clnt); 280 281 if (unlikely(status < 0)) 282 goto out_call_err; 283 284 return; 285 286 out_clnt_err: 287 dprintk("NFS: failed to create UMNT RPC client, status=%ld\n", 288 PTR_ERR(clnt)); 289 return; 290 291 out_call_err: 292 dprintk("NFS: UMNT request failed, status=%d\n", status); 293 } 294 295 /* 296 * XDR encode/decode functions for MOUNT 297 */ 298 299 static void encode_mntdirpath(struct xdr_stream *xdr, const char *pathname) 300 { 301 const u32 pathname_len = strlen(pathname); 302 __be32 *p; 303 304 p = xdr_reserve_space(xdr, 4 + pathname_len); 305 xdr_encode_opaque(p, pathname, pathname_len); 306 } 307 308 static void mnt_xdr_enc_dirpath(struct rpc_rqst *req, struct xdr_stream *xdr, 309 const char *dirpath) 310 { 311 encode_mntdirpath(xdr, dirpath); 312 } 313 314 /* 315 * RFC 1094: "A non-zero status indicates some sort of error. In this 316 * case, the status is a UNIX error number." This can be problematic 317 * if the server and client use different errno values for the same 318 * error. 319 * 320 * However, the OpenGroup XNFS spec provides a simple mapping that is 321 * independent of local errno values on the server and the client. 322 */ 323 static int decode_status(struct xdr_stream *xdr, struct mountres *res) 324 { 325 unsigned int i; 326 u32 status; 327 __be32 *p; 328 329 p = xdr_inline_decode(xdr, 4); 330 if (unlikely(p == NULL)) 331 return -EIO; 332 status = be32_to_cpup(p); 333 334 for (i = 0; i < ARRAY_SIZE(mnt_errtbl); i++) { 335 if (mnt_errtbl[i].status == status) { 336 res->errno = mnt_errtbl[i].errno; 337 return 0; 338 } 339 } 340 341 dprintk("NFS: unrecognized MNT status code: %u\n", status); 342 res->errno = -EACCES; 343 return 0; 344 } 345 346 static int decode_fhandle(struct xdr_stream *xdr, struct mountres *res) 347 { 348 struct nfs_fh *fh = res->fh; 349 __be32 *p; 350 351 p = xdr_inline_decode(xdr, NFS2_FHSIZE); 352 if (unlikely(p == NULL)) 353 return -EIO; 354 355 fh->size = NFS2_FHSIZE; 356 memcpy(fh->data, p, NFS2_FHSIZE); 357 return 0; 358 } 359 360 static int mnt_xdr_dec_mountres(struct rpc_rqst *req, 361 struct xdr_stream *xdr, 362 struct mountres *res) 363 { 364 int status; 365 366 status = decode_status(xdr, res); 367 if (unlikely(status != 0 || res->errno != 0)) 368 return status; 369 return decode_fhandle(xdr, res); 370 } 371 372 static int decode_fhs_status(struct xdr_stream *xdr, struct mountres *res) 373 { 374 unsigned int i; 375 u32 status; 376 __be32 *p; 377 378 p = xdr_inline_decode(xdr, 4); 379 if (unlikely(p == NULL)) 380 return -EIO; 381 status = be32_to_cpup(p); 382 383 for (i = 0; i < ARRAY_SIZE(mnt3_errtbl); i++) { 384 if (mnt3_errtbl[i].status == status) { 385 res->errno = mnt3_errtbl[i].errno; 386 return 0; 387 } 388 } 389 390 dprintk("NFS: unrecognized MNT3 status code: %u\n", status); 391 res->errno = -EACCES; 392 return 0; 393 } 394 395 static int decode_fhandle3(struct xdr_stream *xdr, struct mountres *res) 396 { 397 struct nfs_fh *fh = res->fh; 398 u32 size; 399 __be32 *p; 400 401 p = xdr_inline_decode(xdr, 4); 402 if (unlikely(p == NULL)) 403 return -EIO; 404 405 size = be32_to_cpup(p); 406 if (size > NFS3_FHSIZE || size == 0) 407 return -EIO; 408 409 p = xdr_inline_decode(xdr, size); 410 if (unlikely(p == NULL)) 411 return -EIO; 412 413 fh->size = size; 414 memcpy(fh->data, p, size); 415 return 0; 416 } 417 418 static int decode_auth_flavors(struct xdr_stream *xdr, struct mountres *res) 419 { 420 rpc_authflavor_t *flavors = res->auth_flavors; 421 unsigned int *count = res->auth_count; 422 u32 entries, i; 423 __be32 *p; 424 425 if (*count == 0) 426 return 0; 427 428 p = xdr_inline_decode(xdr, 4); 429 if (unlikely(p == NULL)) 430 return -EIO; 431 entries = be32_to_cpup(p); 432 dprintk("NFS: received %u auth flavors\n", entries); 433 if (entries > NFS_MAX_SECFLAVORS) 434 entries = NFS_MAX_SECFLAVORS; 435 436 p = xdr_inline_decode(xdr, 4 * entries); 437 if (unlikely(p == NULL)) 438 return -EIO; 439 440 if (entries > *count) 441 entries = *count; 442 443 for (i = 0; i < entries; i++) { 444 flavors[i] = be32_to_cpup(p++); 445 dprintk("NFS: auth flavor[%u]: %d\n", i, flavors[i]); 446 } 447 *count = i; 448 449 return 0; 450 } 451 452 static int mnt_xdr_dec_mountres3(struct rpc_rqst *req, 453 struct xdr_stream *xdr, 454 struct mountres *res) 455 { 456 int status; 457 458 status = decode_fhs_status(xdr, res); 459 if (unlikely(status != 0 || res->errno != 0)) 460 return status; 461 status = decode_fhandle3(xdr, res); 462 if (unlikely(status != 0)) { 463 res->errno = -EBADHANDLE; 464 return 0; 465 } 466 return decode_auth_flavors(xdr, res); 467 } 468 469 static struct rpc_procinfo mnt_procedures[] = { 470 [MOUNTPROC_MNT] = { 471 .p_proc = MOUNTPROC_MNT, 472 .p_encode = (kxdreproc_t)mnt_xdr_enc_dirpath, 473 .p_decode = (kxdrdproc_t)mnt_xdr_dec_mountres, 474 .p_arglen = MNT_enc_dirpath_sz, 475 .p_replen = MNT_dec_mountres_sz, 476 .p_statidx = MOUNTPROC_MNT, 477 .p_name = "MOUNT", 478 }, 479 [MOUNTPROC_UMNT] = { 480 .p_proc = MOUNTPROC_UMNT, 481 .p_encode = (kxdreproc_t)mnt_xdr_enc_dirpath, 482 .p_arglen = MNT_enc_dirpath_sz, 483 .p_statidx = MOUNTPROC_UMNT, 484 .p_name = "UMOUNT", 485 }, 486 }; 487 488 static struct rpc_procinfo mnt3_procedures[] = { 489 [MOUNTPROC3_MNT] = { 490 .p_proc = MOUNTPROC3_MNT, 491 .p_encode = (kxdreproc_t)mnt_xdr_enc_dirpath, 492 .p_decode = (kxdrdproc_t)mnt_xdr_dec_mountres3, 493 .p_arglen = MNT_enc_dirpath_sz, 494 .p_replen = MNT_dec_mountres3_sz, 495 .p_statidx = MOUNTPROC3_MNT, 496 .p_name = "MOUNT", 497 }, 498 [MOUNTPROC3_UMNT] = { 499 .p_proc = MOUNTPROC3_UMNT, 500 .p_encode = (kxdreproc_t)mnt_xdr_enc_dirpath, 501 .p_arglen = MNT_enc_dirpath_sz, 502 .p_statidx = MOUNTPROC3_UMNT, 503 .p_name = "UMOUNT", 504 }, 505 }; 506 507 508 static const struct rpc_version mnt_version1 = { 509 .number = 1, 510 .nrprocs = ARRAY_SIZE(mnt_procedures), 511 .procs = mnt_procedures, 512 }; 513 514 static const struct rpc_version mnt_version3 = { 515 .number = 3, 516 .nrprocs = ARRAY_SIZE(mnt3_procedures), 517 .procs = mnt3_procedures, 518 }; 519 520 static const struct rpc_version *mnt_version[] = { 521 NULL, 522 &mnt_version1, 523 NULL, 524 &mnt_version3, 525 }; 526 527 static struct rpc_stat mnt_stats; 528 529 static const struct rpc_program mnt_program = { 530 .name = "mount", 531 .number = NFS_MNT_PROGRAM, 532 .nrvers = ARRAY_SIZE(mnt_version), 533 .version = mnt_version, 534 .stats = &mnt_stats, 535 }; 536