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. 143 */ 144 int nfs_mount(struct nfs_mount_request *info) 145 { 146 struct mountres result = { 147 .fh = info->fh, 148 .auth_count = info->auth_flav_len, 149 .auth_flavors = info->auth_flavs, 150 }; 151 struct rpc_message msg = { 152 .rpc_argp = info->dirpath, 153 .rpc_resp = &result, 154 }; 155 struct rpc_create_args args = { 156 .net = info->net, 157 .protocol = info->protocol, 158 .address = info->sap, 159 .addrsize = info->salen, 160 .servername = info->hostname, 161 .program = &mnt_program, 162 .version = info->version, 163 .authflavor = RPC_AUTH_UNIX, 164 }; 165 struct rpc_clnt *mnt_clnt; 166 int status; 167 168 dprintk("NFS: sending MNT request for %s:%s\n", 169 (info->hostname ? info->hostname : "server"), 170 info->dirpath); 171 172 if (strlen(info->dirpath) > MNTPATHLEN) 173 return -ENAMETOOLONG; 174 175 if (info->noresvport) 176 args.flags |= RPC_CLNT_CREATE_NONPRIVPORT; 177 178 mnt_clnt = rpc_create(&args); 179 if (IS_ERR(mnt_clnt)) 180 goto out_clnt_err; 181 182 if (info->version == NFS_MNT3_VERSION) 183 msg.rpc_proc = &mnt_clnt->cl_procinfo[MOUNTPROC3_MNT]; 184 else 185 msg.rpc_proc = &mnt_clnt->cl_procinfo[MOUNTPROC_MNT]; 186 187 status = rpc_call_sync(mnt_clnt, &msg, RPC_TASK_SOFT|RPC_TASK_TIMEOUT); 188 rpc_shutdown_client(mnt_clnt); 189 190 if (status < 0) 191 goto out_call_err; 192 if (result.errno != 0) 193 goto out_mnt_err; 194 195 dprintk("NFS: MNT request succeeded\n"); 196 status = 0; 197 198 out: 199 return status; 200 201 out_clnt_err: 202 status = PTR_ERR(mnt_clnt); 203 dprintk("NFS: failed to create MNT RPC client, status=%d\n", status); 204 goto out; 205 206 out_call_err: 207 dprintk("NFS: MNT request failed, status=%d\n", status); 208 goto out; 209 210 out_mnt_err: 211 dprintk("NFS: MNT server returned result %d\n", result.errno); 212 status = result.errno; 213 goto out; 214 } 215 216 /** 217 * nfs_umount - Notify a server that we have unmounted this export 218 * @info: pointer to umount request arguments 219 * 220 * MOUNTPROC_UMNT is advisory, so we set a short timeout, and always 221 * use UDP. 222 */ 223 void nfs_umount(const struct nfs_mount_request *info) 224 { 225 static const struct rpc_timeout nfs_umnt_timeout = { 226 .to_initval = 1 * HZ, 227 .to_maxval = 3 * HZ, 228 .to_retries = 2, 229 }; 230 struct rpc_create_args args = { 231 .net = info->net, 232 .protocol = IPPROTO_UDP, 233 .address = info->sap, 234 .addrsize = info->salen, 235 .timeout = &nfs_umnt_timeout, 236 .servername = info->hostname, 237 .program = &mnt_program, 238 .version = info->version, 239 .authflavor = RPC_AUTH_UNIX, 240 .flags = RPC_CLNT_CREATE_NOPING, 241 }; 242 struct rpc_message msg = { 243 .rpc_argp = info->dirpath, 244 }; 245 struct rpc_clnt *clnt; 246 int status; 247 248 if (strlen(info->dirpath) > MNTPATHLEN) 249 return; 250 251 if (info->noresvport) 252 args.flags |= RPC_CLNT_CREATE_NONPRIVPORT; 253 254 clnt = rpc_create(&args); 255 if (IS_ERR(clnt)) 256 goto out_clnt_err; 257 258 dprintk("NFS: sending UMNT request for %s:%s\n", 259 (info->hostname ? info->hostname : "server"), info->dirpath); 260 261 if (info->version == NFS_MNT3_VERSION) 262 msg.rpc_proc = &clnt->cl_procinfo[MOUNTPROC3_UMNT]; 263 else 264 msg.rpc_proc = &clnt->cl_procinfo[MOUNTPROC_UMNT]; 265 266 status = rpc_call_sync(clnt, &msg, 0); 267 rpc_shutdown_client(clnt); 268 269 if (unlikely(status < 0)) 270 goto out_call_err; 271 272 return; 273 274 out_clnt_err: 275 dprintk("NFS: failed to create UMNT RPC client, status=%ld\n", 276 PTR_ERR(clnt)); 277 return; 278 279 out_call_err: 280 dprintk("NFS: UMNT request failed, status=%d\n", status); 281 } 282 283 /* 284 * XDR encode/decode functions for MOUNT 285 */ 286 287 static void encode_mntdirpath(struct xdr_stream *xdr, const char *pathname) 288 { 289 const u32 pathname_len = strlen(pathname); 290 __be32 *p; 291 292 p = xdr_reserve_space(xdr, 4 + pathname_len); 293 xdr_encode_opaque(p, pathname, pathname_len); 294 } 295 296 static void mnt_xdr_enc_dirpath(struct rpc_rqst *req, struct xdr_stream *xdr, 297 const char *dirpath) 298 { 299 encode_mntdirpath(xdr, dirpath); 300 } 301 302 /* 303 * RFC 1094: "A non-zero status indicates some sort of error. In this 304 * case, the status is a UNIX error number." This can be problematic 305 * if the server and client use different errno values for the same 306 * error. 307 * 308 * However, the OpenGroup XNFS spec provides a simple mapping that is 309 * independent of local errno values on the server and the client. 310 */ 311 static int decode_status(struct xdr_stream *xdr, struct mountres *res) 312 { 313 unsigned int i; 314 u32 status; 315 __be32 *p; 316 317 p = xdr_inline_decode(xdr, 4); 318 if (unlikely(p == NULL)) 319 return -EIO; 320 status = be32_to_cpup(p); 321 322 for (i = 0; i < ARRAY_SIZE(mnt_errtbl); i++) { 323 if (mnt_errtbl[i].status == status) { 324 res->errno = mnt_errtbl[i].errno; 325 return 0; 326 } 327 } 328 329 dprintk("NFS: unrecognized MNT status code: %u\n", status); 330 res->errno = -EACCES; 331 return 0; 332 } 333 334 static int decode_fhandle(struct xdr_stream *xdr, struct mountres *res) 335 { 336 struct nfs_fh *fh = res->fh; 337 __be32 *p; 338 339 p = xdr_inline_decode(xdr, NFS2_FHSIZE); 340 if (unlikely(p == NULL)) 341 return -EIO; 342 343 fh->size = NFS2_FHSIZE; 344 memcpy(fh->data, p, NFS2_FHSIZE); 345 return 0; 346 } 347 348 static int mnt_xdr_dec_mountres(struct rpc_rqst *req, 349 struct xdr_stream *xdr, 350 struct mountres *res) 351 { 352 int status; 353 354 status = decode_status(xdr, res); 355 if (unlikely(status != 0 || res->errno != 0)) 356 return status; 357 return decode_fhandle(xdr, res); 358 } 359 360 static int decode_fhs_status(struct xdr_stream *xdr, struct mountres *res) 361 { 362 unsigned int i; 363 u32 status; 364 __be32 *p; 365 366 p = xdr_inline_decode(xdr, 4); 367 if (unlikely(p == NULL)) 368 return -EIO; 369 status = be32_to_cpup(p); 370 371 for (i = 0; i < ARRAY_SIZE(mnt3_errtbl); i++) { 372 if (mnt3_errtbl[i].status == status) { 373 res->errno = mnt3_errtbl[i].errno; 374 return 0; 375 } 376 } 377 378 dprintk("NFS: unrecognized MNT3 status code: %u\n", status); 379 res->errno = -EACCES; 380 return 0; 381 } 382 383 static int decode_fhandle3(struct xdr_stream *xdr, struct mountres *res) 384 { 385 struct nfs_fh *fh = res->fh; 386 u32 size; 387 __be32 *p; 388 389 p = xdr_inline_decode(xdr, 4); 390 if (unlikely(p == NULL)) 391 return -EIO; 392 393 size = be32_to_cpup(p); 394 if (size > NFS3_FHSIZE || size == 0) 395 return -EIO; 396 397 p = xdr_inline_decode(xdr, size); 398 if (unlikely(p == NULL)) 399 return -EIO; 400 401 fh->size = size; 402 memcpy(fh->data, p, size); 403 return 0; 404 } 405 406 static int decode_auth_flavors(struct xdr_stream *xdr, struct mountres *res) 407 { 408 rpc_authflavor_t *flavors = res->auth_flavors; 409 unsigned int *count = res->auth_count; 410 u32 entries, i; 411 __be32 *p; 412 413 if (*count == 0) 414 return 0; 415 416 p = xdr_inline_decode(xdr, 4); 417 if (unlikely(p == NULL)) 418 return -EIO; 419 entries = be32_to_cpup(p); 420 dprintk("NFS: received %u auth flavors\n", entries); 421 if (entries > NFS_MAX_SECFLAVORS) 422 entries = NFS_MAX_SECFLAVORS; 423 424 p = xdr_inline_decode(xdr, 4 * entries); 425 if (unlikely(p == NULL)) 426 return -EIO; 427 428 if (entries > *count) 429 entries = *count; 430 431 for (i = 0; i < entries; i++) { 432 flavors[i] = be32_to_cpup(p++); 433 dprintk("NFS: auth flavor[%u]: %d\n", i, flavors[i]); 434 } 435 *count = i; 436 437 return 0; 438 } 439 440 static int mnt_xdr_dec_mountres3(struct rpc_rqst *req, 441 struct xdr_stream *xdr, 442 struct mountres *res) 443 { 444 int status; 445 446 status = decode_fhs_status(xdr, res); 447 if (unlikely(status != 0 || res->errno != 0)) 448 return status; 449 status = decode_fhandle3(xdr, res); 450 if (unlikely(status != 0)) { 451 res->errno = -EBADHANDLE; 452 return 0; 453 } 454 return decode_auth_flavors(xdr, res); 455 } 456 457 static struct rpc_procinfo mnt_procedures[] = { 458 [MOUNTPROC_MNT] = { 459 .p_proc = MOUNTPROC_MNT, 460 .p_encode = (kxdreproc_t)mnt_xdr_enc_dirpath, 461 .p_decode = (kxdrdproc_t)mnt_xdr_dec_mountres, 462 .p_arglen = MNT_enc_dirpath_sz, 463 .p_replen = MNT_dec_mountres_sz, 464 .p_statidx = MOUNTPROC_MNT, 465 .p_name = "MOUNT", 466 }, 467 [MOUNTPROC_UMNT] = { 468 .p_proc = MOUNTPROC_UMNT, 469 .p_encode = (kxdreproc_t)mnt_xdr_enc_dirpath, 470 .p_arglen = MNT_enc_dirpath_sz, 471 .p_statidx = MOUNTPROC_UMNT, 472 .p_name = "UMOUNT", 473 }, 474 }; 475 476 static struct rpc_procinfo mnt3_procedures[] = { 477 [MOUNTPROC3_MNT] = { 478 .p_proc = MOUNTPROC3_MNT, 479 .p_encode = (kxdreproc_t)mnt_xdr_enc_dirpath, 480 .p_decode = (kxdrdproc_t)mnt_xdr_dec_mountres3, 481 .p_arglen = MNT_enc_dirpath_sz, 482 .p_replen = MNT_dec_mountres3_sz, 483 .p_statidx = MOUNTPROC3_MNT, 484 .p_name = "MOUNT", 485 }, 486 [MOUNTPROC3_UMNT] = { 487 .p_proc = MOUNTPROC3_UMNT, 488 .p_encode = (kxdreproc_t)mnt_xdr_enc_dirpath, 489 .p_arglen = MNT_enc_dirpath_sz, 490 .p_statidx = MOUNTPROC3_UMNT, 491 .p_name = "UMOUNT", 492 }, 493 }; 494 495 496 static const struct rpc_version mnt_version1 = { 497 .number = 1, 498 .nrprocs = ARRAY_SIZE(mnt_procedures), 499 .procs = mnt_procedures, 500 }; 501 502 static const struct rpc_version mnt_version3 = { 503 .number = 3, 504 .nrprocs = ARRAY_SIZE(mnt3_procedures), 505 .procs = mnt3_procedures, 506 }; 507 508 static const struct rpc_version *mnt_version[] = { 509 NULL, 510 &mnt_version1, 511 NULL, 512 &mnt_version3, 513 }; 514 515 static struct rpc_stat mnt_stats; 516 517 static const struct rpc_program mnt_program = { 518 .name = "mount", 519 .number = NFS_MNT_PROGRAM, 520 .nrvers = ARRAY_SIZE(mnt_version), 521 .version = mnt_version, 522 .stats = &mnt_stats, 523 }; 524