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