1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or https://opensource.org/licenses/CDDL-1.0. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 22 /* 23 * Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved. 24 * Copyright (c) 2011 Gunnar Beutner 25 * Copyright (c) 2012 Cyril Plisko. All rights reserved. 26 * Copyright (c) 2019, 2022 by Delphix. All rights reserved. 27 */ 28 29 #include <dirent.h> 30 #include <stdio.h> 31 #include <string.h> 32 #include <errno.h> 33 #include <fcntl.h> 34 #include <sys/file.h> 35 #include <sys/stat.h> 36 #include <sys/types.h> 37 #include <sys/wait.h> 38 #include <unistd.h> 39 #include <libzfs.h> 40 #include <libshare.h> 41 #include "libshare_impl.h" 42 #include "nfs.h" 43 44 #define ZFS_EXPORTS_DIR "/etc/exports.d" 45 #define ZFS_EXPORTS_FILE ZFS_EXPORTS_DIR"/zfs.exports" 46 #define ZFS_EXPORTS_LOCK ZFS_EXPORTS_FILE".lock" 47 48 49 static boolean_t nfs_available(void); 50 51 typedef int (*nfs_shareopt_callback_t)(const char *opt, const char *value, 52 void *cookie); 53 54 typedef int (*nfs_host_callback_t)(FILE *tmpfile, const char *sharepath, 55 const char *host, const char *security, const char *access, void *cookie); 56 57 /* 58 * Invokes the specified callback function for each Solaris share option 59 * listed in the specified string. 60 */ 61 static int 62 foreach_nfs_shareopt(const char *shareopts, 63 nfs_shareopt_callback_t callback, void *cookie) 64 { 65 char *shareopts_dup, *opt, *cur, *value; 66 int was_nul, error; 67 68 if (shareopts == NULL) 69 return (SA_OK); 70 71 if (strcmp(shareopts, "on") == 0) 72 shareopts = "rw,crossmnt"; 73 74 shareopts_dup = strdup(shareopts); 75 76 77 if (shareopts_dup == NULL) 78 return (SA_NO_MEMORY); 79 80 opt = shareopts_dup; 81 was_nul = 0; 82 83 while (1) { 84 cur = opt; 85 86 while (*cur != ',' && *cur != '\0') 87 cur++; 88 89 if (*cur == '\0') 90 was_nul = 1; 91 92 *cur = '\0'; 93 94 if (cur > opt) { 95 value = strchr(opt, '='); 96 97 if (value != NULL) { 98 *value = '\0'; 99 value++; 100 } 101 102 error = callback(opt, value, cookie); 103 104 if (error != SA_OK) { 105 free(shareopts_dup); 106 return (error); 107 } 108 } 109 110 opt = cur + 1; 111 112 if (was_nul) 113 break; 114 } 115 116 free(shareopts_dup); 117 118 return (SA_OK); 119 } 120 121 typedef struct nfs_host_cookie_s { 122 nfs_host_callback_t callback; 123 const char *sharepath; 124 void *cookie; 125 FILE *tmpfile; 126 const char *security; 127 } nfs_host_cookie_t; 128 129 /* 130 * Helper function for foreach_nfs_host. This function checks whether the 131 * current share option is a host specification and invokes a callback 132 * function with information about the host. 133 */ 134 static int 135 foreach_nfs_host_cb(const char *opt, const char *value, void *pcookie) 136 { 137 int error; 138 const char *access; 139 char *host_dup, *host, *next, *v6Literal; 140 nfs_host_cookie_t *udata = (nfs_host_cookie_t *)pcookie; 141 int cidr_len; 142 143 #ifdef DEBUG 144 fprintf(stderr, "foreach_nfs_host_cb: key=%s, value=%s\n", opt, value); 145 #endif 146 147 if (strcmp(opt, "sec") == 0) 148 udata->security = value; 149 150 if (strcmp(opt, "rw") == 0 || strcmp(opt, "ro") == 0) { 151 if (value == NULL) 152 value = "*"; 153 154 access = opt; 155 156 host_dup = strdup(value); 157 158 if (host_dup == NULL) 159 return (SA_NO_MEMORY); 160 161 host = host_dup; 162 163 do { 164 if (*host == '[') { 165 host++; 166 v6Literal = strchr(host, ']'); 167 if (v6Literal == NULL) { 168 free(host_dup); 169 return (SA_SYNTAX_ERR); 170 } 171 if (v6Literal[1] == '\0') { 172 *v6Literal = '\0'; 173 next = NULL; 174 } else if (v6Literal[1] == '/') { 175 next = strchr(v6Literal + 2, ':'); 176 if (next == NULL) { 177 cidr_len = 178 strlen(v6Literal + 1); 179 memmove(v6Literal, 180 v6Literal + 1, 181 cidr_len); 182 v6Literal[cidr_len] = '\0'; 183 } else { 184 cidr_len = next - v6Literal - 1; 185 memmove(v6Literal, 186 v6Literal + 1, 187 cidr_len); 188 v6Literal[cidr_len] = '\0'; 189 next++; 190 } 191 } else if (v6Literal[1] == ':') { 192 *v6Literal = '\0'; 193 next = v6Literal + 2; 194 } else { 195 free(host_dup); 196 return (SA_SYNTAX_ERR); 197 } 198 } else { 199 next = strchr(host, ':'); 200 if (next != NULL) { 201 *next = '\0'; 202 next++; 203 } 204 } 205 206 error = udata->callback(udata->tmpfile, 207 udata->sharepath, host, udata->security, 208 access, udata->cookie); 209 210 if (error != SA_OK) { 211 free(host_dup); 212 213 return (error); 214 } 215 216 host = next; 217 } while (host != NULL); 218 219 free(host_dup); 220 } 221 222 return (SA_OK); 223 } 224 225 /* 226 * Invokes a callback function for all NFS hosts that are set for a share. 227 */ 228 static int 229 foreach_nfs_host(sa_share_impl_t impl_share, FILE *tmpfile, 230 nfs_host_callback_t callback, void *cookie) 231 { 232 nfs_host_cookie_t udata; 233 234 udata.callback = callback; 235 udata.sharepath = impl_share->sa_mountpoint; 236 udata.cookie = cookie; 237 udata.tmpfile = tmpfile; 238 udata.security = "sys"; 239 240 return (foreach_nfs_shareopt(impl_share->sa_shareopts, 241 foreach_nfs_host_cb, &udata)); 242 } 243 244 /* 245 * Converts a Solaris NFS host specification to its Linux equivalent. 246 */ 247 static const char * 248 get_linux_hostspec(const char *solaris_hostspec) 249 { 250 /* 251 * For now we just support CIDR masks (e.g. @192.168.0.0/16) and host 252 * wildcards (e.g. *.example.org). 253 */ 254 if (solaris_hostspec[0] == '@') { 255 /* 256 * Solaris host specifier, e.g. @192.168.0.0/16; we just need 257 * to skip the @ in this case 258 */ 259 return (solaris_hostspec + 1); 260 } else { 261 return (solaris_hostspec); 262 } 263 } 264 265 /* 266 * Adds a Linux share option to an array of NFS options. 267 */ 268 static int 269 add_linux_shareopt(char **plinux_opts, const char *key, const char *value) 270 { 271 size_t len = 0; 272 char *new_linux_opts; 273 274 if (*plinux_opts != NULL) 275 len = strlen(*plinux_opts); 276 277 new_linux_opts = realloc(*plinux_opts, len + 1 + strlen(key) + 278 (value ? 1 + strlen(value) : 0) + 1); 279 280 if (new_linux_opts == NULL) 281 return (SA_NO_MEMORY); 282 283 new_linux_opts[len] = '\0'; 284 285 if (len > 0) 286 strcat(new_linux_opts, ","); 287 288 strcat(new_linux_opts, key); 289 290 if (value != NULL) { 291 strcat(new_linux_opts, "="); 292 strcat(new_linux_opts, value); 293 } 294 295 *plinux_opts = new_linux_opts; 296 297 return (SA_OK); 298 } 299 300 static int string_cmp(const void *lhs, const void *rhs) { 301 const char *const *l = lhs, *const *r = rhs; 302 return (strcmp(*l, *r)); 303 } 304 305 /* 306 * Validates and converts a single Solaris share option to its Linux 307 * equivalent. 308 */ 309 static int 310 get_linux_shareopts_cb(const char *key, const char *value, void *cookie) 311 { 312 /* This list must remain sorted, since we bsearch() it */ 313 static const char *const valid_keys[] = { "all_squash", "anongid", 314 "anonuid", "async", "auth_nlm", "crossmnt", "fsid", "fsuid", "hide", 315 "insecure", "insecure_locks", "mountpoint", "mp", "no_acl", 316 "no_all_squash", "no_auth_nlm", "no_root_squash", 317 "no_subtree_check", "no_wdelay", "nohide", "refer", "replicas", 318 "root_squash", "secure", "secure_locks", "subtree_check", "sync", 319 "wdelay" }; 320 321 char **plinux_opts = (char **)cookie; 322 323 /* host-specific options, these are taken care of elsewhere */ 324 if (strcmp(key, "ro") == 0 || strcmp(key, "rw") == 0 || 325 strcmp(key, "sec") == 0) 326 return (SA_OK); 327 328 if (strcmp(key, "anon") == 0) 329 key = "anonuid"; 330 331 if (strcmp(key, "root_mapping") == 0) { 332 (void) add_linux_shareopt(plinux_opts, "root_squash", NULL); 333 key = "anonuid"; 334 } 335 336 if (strcmp(key, "nosub") == 0) 337 key = "subtree_check"; 338 339 if (bsearch(&key, valid_keys, ARRAY_SIZE(valid_keys), 340 sizeof (*valid_keys), string_cmp) == NULL) 341 return (SA_SYNTAX_ERR); 342 343 (void) add_linux_shareopt(plinux_opts, key, value); 344 345 return (SA_OK); 346 } 347 348 /* 349 * Takes a string containing Solaris share options (e.g. "sync,no_acl") and 350 * converts them to a NULL-terminated array of Linux NFS options. 351 */ 352 static int 353 get_linux_shareopts(const char *shareopts, char **plinux_opts) 354 { 355 int error; 356 357 assert(plinux_opts != NULL); 358 359 *plinux_opts = NULL; 360 361 /* no_subtree_check - Default as of nfs-utils v1.1.0 */ 362 (void) add_linux_shareopt(plinux_opts, "no_subtree_check", NULL); 363 364 /* mountpoint - Restrict exports to ZFS mountpoints */ 365 (void) add_linux_shareopt(plinux_opts, "mountpoint", NULL); 366 367 error = foreach_nfs_shareopt(shareopts, get_linux_shareopts_cb, 368 plinux_opts); 369 370 if (error != SA_OK) { 371 free(*plinux_opts); 372 *plinux_opts = NULL; 373 } 374 375 return (error); 376 } 377 378 /* 379 * This function populates an entry into /etc/exports.d/zfs.exports. 380 * This file is consumed by the linux nfs server so that zfs shares are 381 * automatically exported upon boot or whenever the nfs server restarts. 382 */ 383 static int 384 nfs_add_entry(FILE *tmpfile, const char *sharepath, 385 const char *host, const char *security, const char *access_opts, 386 void *pcookie) 387 { 388 const char *linux_opts = (const char *)pcookie; 389 390 if (linux_opts == NULL) 391 linux_opts = ""; 392 393 boolean_t need_free; 394 char *mp; 395 int rc = nfs_escape_mountpoint(sharepath, &mp, &need_free); 396 if (rc != SA_OK) 397 return (rc); 398 if (fprintf(tmpfile, "%s %s(sec=%s,%s,%s)\n", mp, 399 get_linux_hostspec(host), security, access_opts, 400 linux_opts) < 0) { 401 fprintf(stderr, "failed to write to temporary file\n"); 402 rc = SA_SYSTEM_ERR; 403 } 404 405 if (need_free) 406 free(mp); 407 return (rc); 408 } 409 410 /* 411 * Enables NFS sharing for the specified share. 412 */ 413 static int 414 nfs_enable_share_impl(sa_share_impl_t impl_share, FILE *tmpfile) 415 { 416 char *linux_opts = NULL; 417 int error = get_linux_shareopts(impl_share->sa_shareopts, &linux_opts); 418 if (error != SA_OK) 419 return (error); 420 421 error = foreach_nfs_host(impl_share, tmpfile, nfs_add_entry, 422 linux_opts); 423 free(linux_opts); 424 return (error); 425 } 426 427 static int 428 nfs_enable_share(sa_share_impl_t impl_share) 429 { 430 if (!nfs_available()) 431 return (SA_SYSTEM_ERR); 432 433 return (nfs_toggle_share( 434 ZFS_EXPORTS_LOCK, ZFS_EXPORTS_FILE, ZFS_EXPORTS_DIR, impl_share, 435 nfs_enable_share_impl)); 436 } 437 438 /* 439 * Disables NFS sharing for the specified share. 440 */ 441 static int 442 nfs_disable_share_impl(sa_share_impl_t impl_share, FILE *tmpfile) 443 { 444 (void) impl_share, (void) tmpfile; 445 return (SA_OK); 446 } 447 448 static int 449 nfs_disable_share(sa_share_impl_t impl_share) 450 { 451 if (!nfs_available()) 452 return (SA_OK); 453 454 return (nfs_toggle_share( 455 ZFS_EXPORTS_LOCK, ZFS_EXPORTS_FILE, ZFS_EXPORTS_DIR, impl_share, 456 nfs_disable_share_impl)); 457 } 458 459 static boolean_t 460 nfs_is_shared(sa_share_impl_t impl_share) 461 { 462 if (!nfs_available()) 463 return (SA_SYSTEM_ERR); 464 465 return (nfs_is_shared_impl(ZFS_EXPORTS_FILE, impl_share)); 466 } 467 468 /* 469 * Checks whether the specified NFS share options are syntactically correct. 470 */ 471 static int 472 nfs_validate_shareopts(const char *shareopts) 473 { 474 char *linux_opts = NULL; 475 int error = get_linux_shareopts(shareopts, &linux_opts); 476 if (error != SA_OK) 477 return (error); 478 479 free(linux_opts); 480 return (SA_OK); 481 } 482 483 static int 484 nfs_commit_shares(void) 485 { 486 if (!nfs_available()) 487 return (SA_SYSTEM_ERR); 488 489 char *argv[] = { 490 (char *)"/usr/sbin/exportfs", 491 (char *)"-ra", 492 NULL 493 }; 494 495 return (libzfs_run_process(argv[0], argv, 0)); 496 } 497 498 static void 499 nfs_truncate_shares(void) 500 { 501 nfs_reset_shares(ZFS_EXPORTS_LOCK, ZFS_EXPORTS_FILE); 502 } 503 504 const sa_fstype_t libshare_nfs_type = { 505 .enable_share = nfs_enable_share, 506 .disable_share = nfs_disable_share, 507 .is_shared = nfs_is_shared, 508 509 .validate_shareopts = nfs_validate_shareopts, 510 .commit_shares = nfs_commit_shares, 511 .truncate_shares = nfs_truncate_shares, 512 }; 513 514 static boolean_t 515 nfs_available(void) 516 { 517 static int avail; 518 519 if (!avail) { 520 if (access("/usr/sbin/exportfs", F_OK) != 0) 521 avail = -1; 522 else 523 avail = 1; 524 } 525 526 return (avail == 1); 527 } 528