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 = -ESERVERFAULT, }, 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 * XDR encode/decode functions for MOUNT 214 */ 215 216 static int encode_mntdirpath(struct xdr_stream *xdr, const char *pathname) 217 { 218 const u32 pathname_len = strlen(pathname); 219 __be32 *p; 220 221 if (unlikely(pathname_len > MNTPATHLEN)) 222 return -EIO; 223 224 p = xdr_reserve_space(xdr, sizeof(u32) + pathname_len); 225 if (unlikely(p == NULL)) 226 return -EIO; 227 xdr_encode_opaque(p, pathname, pathname_len); 228 229 return 0; 230 } 231 232 static int mnt_enc_dirpath(struct rpc_rqst *req, __be32 *p, 233 const char *dirpath) 234 { 235 struct xdr_stream xdr; 236 237 xdr_init_encode(&xdr, &req->rq_snd_buf, p); 238 return encode_mntdirpath(&xdr, dirpath); 239 } 240 241 /* 242 * RFC 1094: "A non-zero status indicates some sort of error. In this 243 * case, the status is a UNIX error number." This can be problematic 244 * if the server and client use different errno values for the same 245 * error. 246 * 247 * However, the OpenGroup XNFS spec provides a simple mapping that is 248 * independent of local errno values on the server and the client. 249 */ 250 static int decode_status(struct xdr_stream *xdr, struct mountres *res) 251 { 252 unsigned int i; 253 u32 status; 254 __be32 *p; 255 256 p = xdr_inline_decode(xdr, sizeof(status)); 257 if (unlikely(p == NULL)) 258 return -EIO; 259 status = ntohl(*p); 260 261 for (i = 0; i <= ARRAY_SIZE(mnt_errtbl); i++) { 262 if (mnt_errtbl[i].status == status) { 263 res->errno = mnt_errtbl[i].errno; 264 return 0; 265 } 266 } 267 268 dprintk("NFS: unrecognized MNT status code: %u\n", status); 269 res->errno = -EACCES; 270 return 0; 271 } 272 273 static int decode_fhandle(struct xdr_stream *xdr, struct mountres *res) 274 { 275 struct nfs_fh *fh = res->fh; 276 __be32 *p; 277 278 p = xdr_inline_decode(xdr, NFS2_FHSIZE); 279 if (unlikely(p == NULL)) 280 return -EIO; 281 282 fh->size = NFS2_FHSIZE; 283 memcpy(fh->data, p, NFS2_FHSIZE); 284 return 0; 285 } 286 287 static int mnt_dec_mountres(struct rpc_rqst *req, __be32 *p, 288 struct mountres *res) 289 { 290 struct xdr_stream xdr; 291 int status; 292 293 xdr_init_decode(&xdr, &req->rq_rcv_buf, p); 294 295 status = decode_status(&xdr, res); 296 if (unlikely(status != 0 || res->errno != 0)) 297 return status; 298 return decode_fhandle(&xdr, res); 299 } 300 301 static int decode_fhs_status(struct xdr_stream *xdr, struct mountres *res) 302 { 303 unsigned int i; 304 u32 status; 305 __be32 *p; 306 307 p = xdr_inline_decode(xdr, sizeof(status)); 308 if (unlikely(p == NULL)) 309 return -EIO; 310 status = ntohl(*p); 311 312 for (i = 0; i <= ARRAY_SIZE(mnt3_errtbl); i++) { 313 if (mnt3_errtbl[i].status == status) { 314 res->errno = mnt3_errtbl[i].errno; 315 return 0; 316 } 317 } 318 319 dprintk("NFS: unrecognized MNT3 status code: %u\n", status); 320 res->errno = -EACCES; 321 return 0; 322 } 323 324 static int decode_fhandle3(struct xdr_stream *xdr, struct mountres *res) 325 { 326 struct nfs_fh *fh = res->fh; 327 u32 size; 328 __be32 *p; 329 330 p = xdr_inline_decode(xdr, sizeof(size)); 331 if (unlikely(p == NULL)) 332 return -EIO; 333 334 size = ntohl(*p++); 335 if (size > NFS3_FHSIZE || size == 0) 336 return -EIO; 337 338 p = xdr_inline_decode(xdr, size); 339 if (unlikely(p == NULL)) 340 return -EIO; 341 342 fh->size = size; 343 memcpy(fh->data, p, size); 344 return 0; 345 } 346 347 static int decode_auth_flavors(struct xdr_stream *xdr, struct mountres *res) 348 { 349 rpc_authflavor_t *flavors = res->auth_flavors; 350 unsigned int *count = res->auth_count; 351 u32 entries, i; 352 __be32 *p; 353 354 if (*count == 0) 355 return 0; 356 357 p = xdr_inline_decode(xdr, sizeof(entries)); 358 if (unlikely(p == NULL)) 359 return -EIO; 360 entries = ntohl(*p); 361 dprintk("NFS: received %u auth flavors\n", entries); 362 if (entries > NFS_MAX_SECFLAVORS) 363 entries = NFS_MAX_SECFLAVORS; 364 365 p = xdr_inline_decode(xdr, sizeof(u32) * entries); 366 if (unlikely(p == NULL)) 367 return -EIO; 368 369 if (entries > *count) 370 entries = *count; 371 372 for (i = 0; i < entries; i++) { 373 flavors[i] = ntohl(*p++); 374 dprintk("NFS:\tflavor %u: %d\n", i, flavors[i]); 375 } 376 *count = i; 377 378 return 0; 379 } 380 381 static int mnt_dec_mountres3(struct rpc_rqst *req, __be32 *p, 382 struct mountres *res) 383 { 384 struct xdr_stream xdr; 385 int status; 386 387 xdr_init_decode(&xdr, &req->rq_rcv_buf, p); 388 389 status = decode_fhs_status(&xdr, res); 390 if (unlikely(status != 0 || res->errno != 0)) 391 return status; 392 status = decode_fhandle3(&xdr, res); 393 if (unlikely(status != 0)) { 394 res->errno = -EBADHANDLE; 395 return 0; 396 } 397 return decode_auth_flavors(&xdr, res); 398 } 399 400 static struct rpc_procinfo mnt_procedures[] = { 401 [MOUNTPROC_MNT] = { 402 .p_proc = MOUNTPROC_MNT, 403 .p_encode = (kxdrproc_t)mnt_enc_dirpath, 404 .p_decode = (kxdrproc_t)mnt_dec_mountres, 405 .p_arglen = MNT_enc_dirpath_sz, 406 .p_replen = MNT_dec_mountres_sz, 407 .p_statidx = MOUNTPROC_MNT, 408 .p_name = "MOUNT", 409 }, 410 }; 411 412 static struct rpc_procinfo mnt3_procedures[] = { 413 [MOUNTPROC3_MNT] = { 414 .p_proc = MOUNTPROC3_MNT, 415 .p_encode = (kxdrproc_t)mnt_enc_dirpath, 416 .p_decode = (kxdrproc_t)mnt_dec_mountres3, 417 .p_arglen = MNT_enc_dirpath_sz, 418 .p_replen = MNT_dec_mountres3_sz, 419 .p_statidx = MOUNTPROC3_MNT, 420 .p_name = "MOUNT", 421 }, 422 }; 423 424 425 static struct rpc_version mnt_version1 = { 426 .number = 1, 427 .nrprocs = 2, 428 .procs = mnt_procedures, 429 }; 430 431 static struct rpc_version mnt_version3 = { 432 .number = 3, 433 .nrprocs = 2, 434 .procs = mnt3_procedures, 435 }; 436 437 static struct rpc_version *mnt_version[] = { 438 NULL, 439 &mnt_version1, 440 NULL, 441 &mnt_version3, 442 }; 443 444 static struct rpc_stat mnt_stats; 445 446 static struct rpc_program mnt_program = { 447 .name = "mount", 448 .number = NFS_MNT_PROGRAM, 449 .nrvers = ARRAY_SIZE(mnt_version), 450 .version = mnt_version, 451 .stats = &mnt_stats, 452 }; 453