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