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 RPC_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 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 .protocol = info->protocol, 157 .address = info->sap, 158 .addrsize = info->salen, 159 .servername = info->hostname, 160 .program = &mnt_program, 161 .version = info->version, 162 .authflavor = RPC_AUTH_UNIX, 163 }; 164 struct rpc_clnt *mnt_clnt; 165 int status; 166 167 dprintk("NFS: sending MNT request for %s:%s\n", 168 (info->hostname ? info->hostname : "server"), 169 info->dirpath); 170 171 if (info->noresvport) 172 args.flags |= RPC_CLNT_CREATE_NONPRIVPORT; 173 174 mnt_clnt = rpc_create(&args); 175 if (IS_ERR(mnt_clnt)) 176 goto out_clnt_err; 177 178 if (info->version == NFS_MNT3_VERSION) 179 msg.rpc_proc = &mnt_clnt->cl_procinfo[MOUNTPROC3_MNT]; 180 else 181 msg.rpc_proc = &mnt_clnt->cl_procinfo[MOUNTPROC_MNT]; 182 183 status = rpc_call_sync(mnt_clnt, &msg, 0); 184 rpc_shutdown_client(mnt_clnt); 185 186 if (status < 0) 187 goto out_call_err; 188 if (result.errno != 0) 189 goto out_mnt_err; 190 191 dprintk("NFS: MNT request succeeded\n"); 192 status = 0; 193 194 out: 195 return status; 196 197 out_clnt_err: 198 status = PTR_ERR(mnt_clnt); 199 dprintk("NFS: failed to create MNT RPC client, status=%d\n", status); 200 goto out; 201 202 out_call_err: 203 dprintk("NFS: MNT request failed, status=%d\n", status); 204 goto out; 205 206 out_mnt_err: 207 dprintk("NFS: MNT server returned result %d\n", result.errno); 208 status = result.errno; 209 goto out; 210 } 211 212 /** 213 * nfs_umount - Notify a server that we have unmounted this export 214 * @info: pointer to umount request arguments 215 * 216 * MOUNTPROC_UMNT is advisory, so we set a short timeout, and always 217 * use UDP. 218 */ 219 void nfs_umount(const struct nfs_mount_request *info) 220 { 221 static const struct rpc_timeout nfs_umnt_timeout = { 222 .to_initval = 1 * HZ, 223 .to_maxval = 3 * HZ, 224 .to_retries = 2, 225 }; 226 struct rpc_create_args args = { 227 .protocol = IPPROTO_UDP, 228 .address = info->sap, 229 .addrsize = info->salen, 230 .timeout = &nfs_umnt_timeout, 231 .servername = info->hostname, 232 .program = &mnt_program, 233 .version = info->version, 234 .authflavor = RPC_AUTH_UNIX, 235 .flags = RPC_CLNT_CREATE_NOPING, 236 }; 237 struct mountres result; 238 struct rpc_message msg = { 239 .rpc_argp = info->dirpath, 240 .rpc_resp = &result, 241 }; 242 struct rpc_clnt *clnt; 243 int status; 244 245 if (info->noresvport) 246 args.flags |= RPC_CLNT_CREATE_NONPRIVPORT; 247 248 clnt = rpc_create(&args); 249 if (unlikely(IS_ERR(clnt))) 250 goto out_clnt_err; 251 252 dprintk("NFS: sending UMNT request for %s:%s\n", 253 (info->hostname ? info->hostname : "server"), info->dirpath); 254 255 if (info->version == NFS_MNT3_VERSION) 256 msg.rpc_proc = &clnt->cl_procinfo[MOUNTPROC3_UMNT]; 257 else 258 msg.rpc_proc = &clnt->cl_procinfo[MOUNTPROC_UMNT]; 259 260 status = rpc_call_sync(clnt, &msg, 0); 261 rpc_shutdown_client(clnt); 262 263 if (unlikely(status < 0)) 264 goto out_call_err; 265 266 return; 267 268 out_clnt_err: 269 dprintk("NFS: failed to create UMNT RPC client, status=%ld\n", 270 PTR_ERR(clnt)); 271 return; 272 273 out_call_err: 274 dprintk("NFS: UMNT request failed, status=%d\n", status); 275 } 276 277 /* 278 * XDR encode/decode functions for MOUNT 279 */ 280 281 static int encode_mntdirpath(struct xdr_stream *xdr, const char *pathname) 282 { 283 const u32 pathname_len = strlen(pathname); 284 __be32 *p; 285 286 if (unlikely(pathname_len > MNTPATHLEN)) 287 return -EIO; 288 289 p = xdr_reserve_space(xdr, sizeof(u32) + pathname_len); 290 if (unlikely(p == NULL)) 291 return -EIO; 292 xdr_encode_opaque(p, pathname, pathname_len); 293 294 return 0; 295 } 296 297 static int mnt_enc_dirpath(struct rpc_rqst *req, __be32 *p, 298 const char *dirpath) 299 { 300 struct xdr_stream xdr; 301 302 xdr_init_encode(&xdr, &req->rq_snd_buf, p); 303 return encode_mntdirpath(&xdr, dirpath); 304 } 305 306 /* 307 * RFC 1094: "A non-zero status indicates some sort of error. In this 308 * case, the status is a UNIX error number." This can be problematic 309 * if the server and client use different errno values for the same 310 * error. 311 * 312 * However, the OpenGroup XNFS spec provides a simple mapping that is 313 * independent of local errno values on the server and the client. 314 */ 315 static int decode_status(struct xdr_stream *xdr, struct mountres *res) 316 { 317 unsigned int i; 318 u32 status; 319 __be32 *p; 320 321 p = xdr_inline_decode(xdr, sizeof(status)); 322 if (unlikely(p == NULL)) 323 return -EIO; 324 status = ntohl(*p); 325 326 for (i = 0; i < ARRAY_SIZE(mnt_errtbl); i++) { 327 if (mnt_errtbl[i].status == status) { 328 res->errno = mnt_errtbl[i].errno; 329 return 0; 330 } 331 } 332 333 dprintk("NFS: unrecognized MNT status code: %u\n", status); 334 res->errno = -EACCES; 335 return 0; 336 } 337 338 static int decode_fhandle(struct xdr_stream *xdr, struct mountres *res) 339 { 340 struct nfs_fh *fh = res->fh; 341 __be32 *p; 342 343 p = xdr_inline_decode(xdr, NFS2_FHSIZE); 344 if (unlikely(p == NULL)) 345 return -EIO; 346 347 fh->size = NFS2_FHSIZE; 348 memcpy(fh->data, p, NFS2_FHSIZE); 349 return 0; 350 } 351 352 static int mnt_dec_mountres(struct rpc_rqst *req, __be32 *p, 353 struct mountres *res) 354 { 355 struct xdr_stream xdr; 356 int status; 357 358 xdr_init_decode(&xdr, &req->rq_rcv_buf, p); 359 360 status = decode_status(&xdr, res); 361 if (unlikely(status != 0 || res->errno != 0)) 362 return status; 363 return decode_fhandle(&xdr, res); 364 } 365 366 static int decode_fhs_status(struct xdr_stream *xdr, struct mountres *res) 367 { 368 unsigned int i; 369 u32 status; 370 __be32 *p; 371 372 p = xdr_inline_decode(xdr, sizeof(status)); 373 if (unlikely(p == NULL)) 374 return -EIO; 375 status = ntohl(*p); 376 377 for (i = 0; i < ARRAY_SIZE(mnt3_errtbl); i++) { 378 if (mnt3_errtbl[i].status == status) { 379 res->errno = mnt3_errtbl[i].errno; 380 return 0; 381 } 382 } 383 384 dprintk("NFS: unrecognized MNT3 status code: %u\n", status); 385 res->errno = -EACCES; 386 return 0; 387 } 388 389 static int decode_fhandle3(struct xdr_stream *xdr, struct mountres *res) 390 { 391 struct nfs_fh *fh = res->fh; 392 u32 size; 393 __be32 *p; 394 395 p = xdr_inline_decode(xdr, sizeof(size)); 396 if (unlikely(p == NULL)) 397 return -EIO; 398 399 size = ntohl(*p++); 400 if (size > NFS3_FHSIZE || size == 0) 401 return -EIO; 402 403 p = xdr_inline_decode(xdr, size); 404 if (unlikely(p == NULL)) 405 return -EIO; 406 407 fh->size = size; 408 memcpy(fh->data, p, size); 409 return 0; 410 } 411 412 static int decode_auth_flavors(struct xdr_stream *xdr, struct mountres *res) 413 { 414 rpc_authflavor_t *flavors = res->auth_flavors; 415 unsigned int *count = res->auth_count; 416 u32 entries, i; 417 __be32 *p; 418 419 if (*count == 0) 420 return 0; 421 422 p = xdr_inline_decode(xdr, sizeof(entries)); 423 if (unlikely(p == NULL)) 424 return -EIO; 425 entries = ntohl(*p); 426 dprintk("NFS: received %u auth flavors\n", entries); 427 if (entries > NFS_MAX_SECFLAVORS) 428 entries = NFS_MAX_SECFLAVORS; 429 430 p = xdr_inline_decode(xdr, sizeof(u32) * entries); 431 if (unlikely(p == NULL)) 432 return -EIO; 433 434 if (entries > *count) 435 entries = *count; 436 437 for (i = 0; i < entries; i++) { 438 flavors[i] = ntohl(*p++); 439 dprintk("NFS:\tflavor %u: %d\n", i, flavors[i]); 440 } 441 *count = i; 442 443 return 0; 444 } 445 446 static int mnt_dec_mountres3(struct rpc_rqst *req, __be32 *p, 447 struct mountres *res) 448 { 449 struct xdr_stream xdr; 450 int status; 451 452 xdr_init_decode(&xdr, &req->rq_rcv_buf, p); 453 454 status = decode_fhs_status(&xdr, res); 455 if (unlikely(status != 0 || res->errno != 0)) 456 return status; 457 status = decode_fhandle3(&xdr, res); 458 if (unlikely(status != 0)) { 459 res->errno = -EBADHANDLE; 460 return 0; 461 } 462 return decode_auth_flavors(&xdr, res); 463 } 464 465 static struct rpc_procinfo mnt_procedures[] = { 466 [MOUNTPROC_MNT] = { 467 .p_proc = MOUNTPROC_MNT, 468 .p_encode = (kxdrproc_t)mnt_enc_dirpath, 469 .p_decode = (kxdrproc_t)mnt_dec_mountres, 470 .p_arglen = MNT_enc_dirpath_sz, 471 .p_replen = MNT_dec_mountres_sz, 472 .p_statidx = MOUNTPROC_MNT, 473 .p_name = "MOUNT", 474 }, 475 [MOUNTPROC_UMNT] = { 476 .p_proc = MOUNTPROC_UMNT, 477 .p_encode = (kxdrproc_t)mnt_enc_dirpath, 478 .p_arglen = MNT_enc_dirpath_sz, 479 .p_statidx = MOUNTPROC_UMNT, 480 .p_name = "UMOUNT", 481 }, 482 }; 483 484 static struct rpc_procinfo mnt3_procedures[] = { 485 [MOUNTPROC3_MNT] = { 486 .p_proc = MOUNTPROC3_MNT, 487 .p_encode = (kxdrproc_t)mnt_enc_dirpath, 488 .p_decode = (kxdrproc_t)mnt_dec_mountres3, 489 .p_arglen = MNT_enc_dirpath_sz, 490 .p_replen = MNT_dec_mountres3_sz, 491 .p_statidx = MOUNTPROC3_MNT, 492 .p_name = "MOUNT", 493 }, 494 [MOUNTPROC3_UMNT] = { 495 .p_proc = MOUNTPROC3_UMNT, 496 .p_encode = (kxdrproc_t)mnt_enc_dirpath, 497 .p_arglen = MNT_enc_dirpath_sz, 498 .p_statidx = MOUNTPROC3_UMNT, 499 .p_name = "UMOUNT", 500 }, 501 }; 502 503 504 static struct rpc_version mnt_version1 = { 505 .number = 1, 506 .nrprocs = 2, 507 .procs = mnt_procedures, 508 }; 509 510 static struct rpc_version mnt_version3 = { 511 .number = 3, 512 .nrprocs = 2, 513 .procs = mnt3_procedures, 514 }; 515 516 static struct rpc_version *mnt_version[] = { 517 NULL, 518 &mnt_version1, 519 NULL, 520 &mnt_version3, 521 }; 522 523 static struct rpc_stat mnt_stats; 524 525 static struct rpc_program mnt_program = { 526 .name = "mount", 527 .number = NFS_MNT_PROGRAM, 528 .nrvers = ARRAY_SIZE(mnt_version), 529 .version = mnt_version, 530 .stats = &mnt_stats, 531 }; 532