1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2005 Jean-Sebastien Pedron 5 * Copyright (c) 2005 Csaba Henk 6 * All rights reserved. 7 * 8 * Copyright (c) 2019 The FreeBSD Foundation 9 * 10 * Portions of this software were developed by BFF Storage Systems under 11 * sponsorship from the FreeBSD Foundation. 12 * 13 * Redistribution and use in source and binary forms, with or without 14 * modification, are permitted provided that the following conditions 15 * are met: 16 * 1. Redistributions of source code must retain the above copyright 17 * notice, this list of conditions and the following disclaimer. 18 * 2. Redistributions in binary form must reproduce the above copyright 19 * notice, this list of conditions and the following disclaimer in the 20 * documentation and/or other materials provided with the distribution. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 */ 35 36 #include <sys/cdefs.h> 37 __FBSDID("$FreeBSD$"); 38 39 #include <sys/param.h> 40 #include <sys/mount.h> 41 #include <sys/uio.h> 42 #include <sys/stat.h> 43 #include <sys/sysctl.h> 44 45 #include <err.h> 46 #include <stdio.h> 47 #include <stdlib.h> 48 #include <string.h> 49 #include <sysexits.h> 50 #include <unistd.h> 51 #include <fcntl.h> 52 #include <signal.h> 53 #include <getopt.h> 54 #include <limits.h> 55 #include <osreldate.h> 56 #include <paths.h> 57 58 #include "mntopts.h" 59 60 #ifndef FUSE4BSD_VERSION 61 #define FUSE4BSD_VERSION "0.3.9-pre1" 62 #endif 63 64 void __usage_short(void); 65 void usage(void); 66 void helpmsg(void); 67 void showversion(void); 68 69 static struct mntopt mopts[] = { 70 #define ALTF_PRIVATE 0x01 71 { "private", 0, ALTF_PRIVATE, 1 }, 72 { "neglect_shares", 0, 0x02, 1 }, 73 { "push_symlinks_in", 0, 0x04, 1 }, 74 { "allow_other", 0, 0x08, 1 }, 75 { "default_permissions", 0, 0x10, 1 }, 76 #define ALTF_MAXREAD 0x20 77 { "max_read=", 0, ALTF_MAXREAD, 1 }, 78 #define ALTF_SUBTYPE 0x40 79 { "subtype=", 0, ALTF_SUBTYPE, 1 }, 80 #define ALTF_FSNAME 0x80 81 { "fsname=", 0, ALTF_FSNAME, 1 }, 82 /* 83 * MOPT_AUTOMOUNTED, included by MOPT_STDOPTS, does not fit into 84 * the 'flags' argument to nmount(2). We have to abuse altflags 85 * to pass it, as string, via iovec. 86 */ 87 #define ALTF_AUTOMOUNTED 0x100 88 { "automounted", 0, ALTF_AUTOMOUNTED, 1 }, 89 #define ALTF_INTR 0x200 90 { "intr", 0, ALTF_INTR, 1 }, 91 /* Linux specific options, we silently ignore them */ 92 { "fd=", 0, 0x00, 1 }, 93 { "rootmode=", 0, 0x00, 1 }, 94 { "user_id=", 0, 0x00, 1 }, 95 { "group_id=", 0, 0x00, 1 }, 96 { "large_read", 0, 0x00, 1 }, 97 /* "nonempty", just the first two chars are stripped off during parsing */ 98 { "nempty", 0, 0x00, 1 }, 99 { "async", 0, MNT_ASYNC, 0}, 100 { "noasync", 1, MNT_ASYNC, 0}, 101 MOPT_STDOPTS, 102 MOPT_END 103 }; 104 105 struct mntval { 106 int mv_flag; 107 void *mv_value; 108 int mv_len; 109 }; 110 111 static struct mntval mvals[] = { 112 { ALTF_MAXREAD, NULL, 0 }, 113 { ALTF_SUBTYPE, NULL, 0 }, 114 { ALTF_FSNAME, NULL, 0 }, 115 { 0, NULL, 0 } 116 }; 117 118 #define DEFAULT_MOUNT_FLAGS ALTF_PRIVATE 119 120 int 121 main(int argc, char *argv[]) 122 { 123 struct iovec *iov; 124 int mntflags, iovlen, verbose = 0; 125 char *dev = NULL, *dir = NULL, mntpath[MAXPATHLEN]; 126 char *devo = NULL, *diro = NULL; 127 char ndev[128], fdstr[15]; 128 int i, done = 0, reject_allow_other = 0, safe_level = 0; 129 int altflags = DEFAULT_MOUNT_FLAGS; 130 int __altflags = DEFAULT_MOUNT_FLAGS; 131 int ch = 0; 132 struct mntopt *mo; 133 struct mntval *mv; 134 static struct option longopts[] = { 135 {"reject-allow_other", no_argument, NULL, 'A'}, 136 {"safe", no_argument, NULL, 'S'}, 137 {"daemon", required_argument, NULL, 'D'}, 138 {"daemon_opts", required_argument, NULL, 'O'}, 139 {"special", required_argument, NULL, 's'}, 140 {"mountpath", required_argument, NULL, 'm'}, 141 {"version", no_argument, NULL, 'V'}, 142 {"help", no_argument, NULL, 'h'}, 143 {0,0,0,0} 144 }; 145 int pid = 0; 146 int fd = -1, fdx; 147 char *ep; 148 char *daemon_str = NULL, *daemon_opts = NULL; 149 150 /* 151 * We want a parsing routine which is not sensitive to 152 * the position of args/opts; it should extract the 153 * first two args and stop at the beginning of the rest. 154 * (This makes it easier to call mount_fusefs from external 155 * utils than it is with a strict "util flags args" syntax.) 156 */ 157 158 iov = NULL; 159 iovlen = 0; 160 mntflags = 0; 161 /* All in all, I feel it more robust this way... */ 162 unsetenv("POSIXLY_CORRECT"); 163 if (getenv("MOUNT_FUSEFS_IGNORE_UNKNOWN")) 164 getmnt_silent = 1; 165 if (getenv("MOUNT_FUSEFS_VERBOSE")) 166 verbose = 1; 167 168 do { 169 for (i = 0; i < 3; i++) { 170 if (optind < argc && argv[optind][0] != '-') { 171 if (dir) { 172 done = 1; 173 break; 174 } 175 if (dev) 176 dir = argv[optind]; 177 else 178 dev = argv[optind]; 179 optind++; 180 } 181 } 182 switch(ch) { 183 case 'A': 184 reject_allow_other = 1; 185 break; 186 case 'S': 187 safe_level = 1; 188 break; 189 case 'D': 190 if (daemon_str) 191 errx(1, "daemon specified inconsistently"); 192 daemon_str = optarg; 193 break; 194 case 'O': 195 if (daemon_opts) 196 errx(1, "daemon opts specified inconsistently"); 197 daemon_opts = optarg; 198 break; 199 case 'o': 200 getmntopts(optarg, mopts, &mntflags, &altflags); 201 for (mv = mvals; mv->mv_flag; ++mv) { 202 if (! (altflags & mv->mv_flag)) 203 continue; 204 for (mo = mopts; mo->m_flag; ++mo) { 205 char *p, *q; 206 207 if (mo->m_flag != mv->mv_flag) 208 continue; 209 p = strstr(optarg, mo->m_option); 210 if (p) { 211 p += strlen(mo->m_option); 212 q = p; 213 while (*q != '\0' && *q != ',') 214 q++; 215 mv->mv_len = q - p + 1; 216 mv->mv_value = malloc(mv->mv_len); 217 if (mv->mv_value == NULL) 218 err(1, "malloc"); 219 memcpy(mv->mv_value, p, mv->mv_len - 1); 220 ((char *)mv->mv_value)[mv->mv_len - 1] = '\0'; 221 break; 222 } 223 } 224 } 225 break; 226 case 's': 227 if (devo) 228 errx(1, "special specified inconsistently"); 229 devo = optarg; 230 break; 231 case 'm': 232 if (diro) 233 errx(1, "mount path specified inconsistently"); 234 diro = optarg; 235 break; 236 case 'v': 237 verbose = 1; 238 break; 239 case 'h': 240 helpmsg(); 241 break; 242 case 'V': 243 showversion(); 244 break; 245 case '\0': 246 break; 247 case '?': 248 default: 249 usage(); 250 } 251 if (done) 252 break; 253 } while ((ch = getopt_long(argc, argv, "AvVho:SD:O:s:m:", longopts, NULL)) != -1); 254 255 argc -= optind; 256 argv += optind; 257 258 if (devo) { 259 if (dev) 260 errx(1, "special specified inconsistently"); 261 dev = devo; 262 } else if (diro) 263 errx(1, "if mountpoint is given via an option, special should also be given via an option"); 264 265 if (diro) { 266 if (dir) 267 errx(1, "mount path specified inconsistently"); 268 dir = diro; 269 } 270 271 if ((! dev) && argc > 0) { 272 dev = *argv++; 273 argc--; 274 } 275 276 if ((! dir) && argc > 0) { 277 dir = *argv++; 278 argc--; 279 } 280 281 if (! (dev && dir)) 282 errx(1, "missing special and/or mountpoint"); 283 284 for (mo = mopts; mo->m_flag; ++mo) { 285 if (altflags & mo->m_flag) { 286 int iov_done = 0; 287 288 if (reject_allow_other && 289 strcmp(mo->m_option, "allow_other") == 0) 290 /* 291 * reject_allow_other is stronger than a 292 * negative of allow_other: if this is set, 293 * allow_other is blocked, period. 294 */ 295 errx(1, "\"allow_other\" usage is banned by respective option"); 296 297 for (mv = mvals; mv->mv_flag; ++mv) { 298 if (mo->m_flag != mv->mv_flag) 299 continue; 300 if (mv->mv_value) { 301 build_iovec(&iov, &iovlen, mo->m_option, mv->mv_value, mv->mv_len); 302 iov_done = 1; 303 break; 304 } 305 } 306 if (! iov_done) 307 build_iovec(&iov, &iovlen, mo->m_option, 308 __DECONST(void *, ""), -1); 309 } 310 if (__altflags & mo->m_flag) { 311 char *uscore_opt; 312 313 if (asprintf(&uscore_opt, "__%s", mo->m_option) == -1) 314 err(1, "failed to allocate memory"); 315 build_iovec(&iov, &iovlen, uscore_opt, 316 __DECONST(void *, ""), -1); 317 free(uscore_opt); 318 } 319 } 320 321 if (getenv("MOUNT_FUSEFS_SAFE")) 322 safe_level = 1; 323 324 if (safe_level > 0 && (argc > 0 || daemon_str || daemon_opts)) 325 errx(1, "safe mode, spawning daemon not allowed"); 326 327 if ((argc > 0 && (daemon_str || daemon_opts)) || 328 (daemon_opts && ! daemon_str)) 329 errx(1, "daemon specified inconsistently"); 330 331 /* 332 * Resolve the mountpoint with realpath(3) and remove unnecessary 333 * slashes from the devicename if there are any. 334 */ 335 if (checkpath(dir, mntpath) != 0) 336 err(1, "%s", mntpath); 337 (void)rmslashes(dev, dev); 338 339 if (strcmp(dev, "auto") == 0) 340 dev = __DECONST(char *, "/dev/fuse"); 341 342 if (strcmp(dev, "/dev/fuse") == 0) { 343 if (! (argc > 0 || daemon_str)) { 344 fprintf(stderr, "Please also specify the fuse daemon to run when mounting via the multiplexer!\n"); 345 usage(); 346 } 347 if ((fd = open(dev, O_RDWR)) < 0) 348 err(1, "failed to open fuse device"); 349 } else { 350 fdx = strtol(dev, &ep, 10); 351 if (*ep == '\0') 352 fd = fdx; 353 } 354 355 /* Identifying device */ 356 if (fd >= 0) { 357 struct stat sbuf; 358 char *ndevbas, *lep; 359 360 if (fstat(fd, &sbuf) == -1) 361 err(1, "cannot stat device file descriptor"); 362 363 strcpy(ndev, _PATH_DEV); 364 ndevbas = ndev + strlen(_PATH_DEV); 365 devname_r(sbuf.st_rdev, S_IFCHR, ndevbas, 366 sizeof(ndev) - strlen(_PATH_DEV)); 367 368 if (strncmp(ndevbas, "fuse", 4)) 369 errx(1, "mounting inappropriate device"); 370 371 strtol(ndevbas + 4, &lep, 10); 372 if (*lep != '\0') 373 errx(1, "mounting inappropriate device"); 374 375 dev = ndev; 376 } 377 378 if (argc > 0 || daemon_str) { 379 char *fds; 380 381 if (fd < 0 && (fd = open(dev, O_RDWR)) < 0) 382 err(1, "failed to open fuse device"); 383 384 if (asprintf(&fds, "%d", fd) == -1) 385 err(1, "failed to allocate memory"); 386 setenv("FUSE_DEV_FD", fds, 1); 387 free(fds); 388 setenv("FUSE_NO_MOUNT", "1", 1); 389 390 if (daemon_str) { 391 char *bgdaemon; 392 int len; 393 394 if (! daemon_opts) 395 daemon_opts = __DECONST(char *, ""); 396 397 len = strlen(daemon_str) + 1 + strlen(daemon_opts) + 398 2 + 1; 399 bgdaemon = calloc(1, len); 400 401 if (! bgdaemon) 402 err(1, "failed to allocate memory"); 403 404 strlcpy(bgdaemon, daemon_str, len); 405 strlcat(bgdaemon, " ", len); 406 strlcat(bgdaemon, daemon_opts, len); 407 strlcat(bgdaemon, " &", len); 408 409 if (system(bgdaemon)) 410 err(1, "failed to call fuse daemon"); 411 } else { 412 if ((pid = fork()) < 0) 413 err(1, "failed to fork for fuse daemon"); 414 415 if (pid == 0) { 416 execvp(argv[0], argv); 417 err(1, "failed to exec fuse daemon"); 418 } 419 } 420 } 421 422 /* Prepare the options vector for nmount(). build_iovec() is declared 423 * in mntopts.h. */ 424 sprintf(fdstr, "%d", fd); 425 build_iovec(&iov, &iovlen, "fstype", __DECONST(void *, "fusefs"), -1); 426 build_iovec(&iov, &iovlen, "fspath", mntpath, -1); 427 build_iovec(&iov, &iovlen, "from", dev, -1); 428 build_iovec(&iov, &iovlen, "fd", fdstr, -1); 429 430 if (verbose) 431 fprintf(stderr, "mounting fuse daemon on device %s\n", dev); 432 433 if (nmount(iov, iovlen, mntflags) < 0) 434 err(EX_OSERR, "%s on %s", dev, mntpath); 435 436 exit(0); 437 } 438 439 void 440 __usage_short(void) { 441 fprintf(stderr, 442 "usage:\n%s [-A|-S|-v|-V|-h|-D daemon|-O args|-s special|-m node|-o option...] special node [daemon args...]\n\n", 443 getprogname()); 444 } 445 446 void 447 usage(void) 448 { 449 struct mntopt *mo; 450 451 __usage_short(); 452 453 fprintf(stderr, "known options:\n"); 454 for (mo = mopts; mo->m_flag; ++mo) 455 fprintf(stderr, "\t%s\n", mo->m_option); 456 457 fprintf(stderr, "\n(use -h for a detailed description of these options)\n"); 458 exit(EX_USAGE); 459 } 460 461 void 462 helpmsg(void) 463 { 464 if (! getenv("MOUNT_FUSEFS_CALL_BY_LIB")) { 465 __usage_short(); 466 fprintf(stderr, "description of options:\n"); 467 } 468 469 /* 470 * The main use case of this function is giving info embedded in general 471 * FUSE lib help output. Therefore the style and the content of the output 472 * tries to fit there as much as possible. 473 */ 474 fprintf(stderr, 475 " -o allow_other allow access to other users\n" 476 /* " -o nonempty allow mounts over non-empty file/dir\n" */ 477 " -o default_permissions enable permission checking by kernel\n" 478 " -o intr interruptible mount\n" 479 " -o fsname=NAME set filesystem name\n" 480 /* 481 " -o large_read issue large read requests (2.4 only)\n" 482 */ 483 " -o subtype=NAME set filesystem type\n" 484 " -o max_read=N set maximum size of read requests\n" 485 " -o noprivate allow secondary mounting of the filesystem\n" 486 " -o neglect_shares don't report EBUSY when unmount attempted\n" 487 " in presence of secondary mounts\n" 488 " -o push_symlinks_in prefix absolute symlinks with mountpoint\n" 489 ); 490 exit(EX_USAGE); 491 } 492 493 void 494 showversion(void) 495 { 496 puts("mount_fusefs [fuse4bsd] version: " FUSE4BSD_VERSION); 497 exit(EX_USAGE); 498 } 499