mdmfs.c revision 169560
1/* 2 * Copyright (c) 2001 Dima Dorfman. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27/* 28 * mdmfs (md/MFS) is a wrapper around mdconfig(8), 29 * newfs(8), and mount(8) that mimics the command line option set of 30 * the deprecated mount_mfs(8). 31 */ 32 33#include <sys/cdefs.h> 34__FBSDID("$FreeBSD: head/sbin/mdmfs/mdmfs.c 169560 2007-05-14 19:23:13Z remko $"); 35 36#include <sys/param.h> 37#include <sys/mdioctl.h> 38#include <sys/stat.h> 39#include <sys/wait.h> 40 41#include <assert.h> 42#include <err.h> 43#include <fcntl.h> 44#include <grp.h> 45#include <paths.h> 46#include <pwd.h> 47#include <stdarg.h> 48#include <stdio.h> 49#include <stdlib.h> 50#include <string.h> 51#include <ctype.h> 52#include <unistd.h> 53 54typedef enum { false, true } bool; 55 56struct mtpt_info { 57 uid_t mi_uid; 58 bool mi_have_uid; 59 gid_t mi_gid; 60 bool mi_have_gid; 61 mode_t mi_mode; 62 bool mi_have_mode; 63}; 64 65static bool debug; /* Emit debugging information? */ 66static bool loudsubs; /* Suppress output from helper programs? */ 67static bool norun; /* Actually run the helper programs? */ 68static int unit; /* The unit we're working with. */ 69static const char *mdname; /* Name of memory disk device (e.g., "md"). */ 70static const char *mdsuffix; /* Suffix of memory disk device (e.g., ".uzip"). */ 71static size_t mdnamelen; /* Length of mdname. */ 72static const char *path_mdconfig =_PATH_MDCONFIG; 73 74static void argappend(char **, const char *, ...) __printflike(2, 3); 75static void debugprintf(const char *, ...) __printflike(1, 2); 76static void do_mdconfig_attach(const char *, const enum md_types); 77static void do_mdconfig_attach_au(const char *, const enum md_types); 78static void do_mdconfig_detach(void); 79static void do_mount(const char *, const char *); 80static void do_mtptsetup(const char *, struct mtpt_info *); 81static void do_newfs(const char *); 82static void extract_ugid(const char *, struct mtpt_info *); 83static int run(int *, const char *, ...) __printflike(2, 3); 84static void usage(void); 85 86int 87main(int argc, char **argv) 88{ 89 struct mtpt_info mi; /* Mountpoint info. */ 90 char *mdconfig_arg, *newfs_arg, /* Args to helper programs. */ 91 *mount_arg; 92 enum md_types mdtype; /* The type of our memory disk. */ 93 bool have_mdtype; 94 bool detach, softdep, autounit, newfs; 95 char *mtpoint, *unitstr; 96 char *p; 97 int ch; 98 void *set; 99 unsigned long ul; 100 101 /* Misc. initialization. */ 102 (void)memset(&mi, '\0', sizeof(mi)); 103 detach = true; 104 softdep = true; 105 autounit = false; 106 newfs = true; 107 have_mdtype = false; 108 mdtype = MD_SWAP; 109 mdname = MD_NAME; 110 mdnamelen = strlen(mdname); 111 /* 112 * Can't set these to NULL. They may be passed to the 113 * respective programs without modification. I.e., we may not 114 * receive any command-line options which will caused them to 115 * be modified. 116 */ 117 mdconfig_arg = strdup(""); 118 newfs_arg = strdup(""); 119 mount_arg = strdup(""); 120 121 /* If we were started as mount_mfs or mfs, imply -C. */ 122 if (strcmp(getprogname(), "mount_mfs") == 0 || 123 strcmp(getprogname(), "mfs") == 0) { 124 /* Make compatibility assumptions. */ 125 mi.mi_mode = 01777; 126 mi.mi_have_mode = true; 127 } 128 129 while ((ch = getopt(argc, argv, 130 "a:b:Cc:Dd:E:e:F:f:hi:LlMm:NnO:o:Pp:Ss:t:Uv:w:X")) != -1) 131 switch (ch) { 132 case 'a': 133 argappend(&newfs_arg, "-a %s", optarg); 134 break; 135 case 'b': 136 argappend(&newfs_arg, "-b %s", optarg); 137 break; 138 case 'C': 139 /* Ignored for compatibility. */ 140 break; 141 case 'c': 142 argappend(&newfs_arg, "-c %s", optarg); 143 break; 144 case 'D': 145 detach = false; 146 break; 147 case 'd': 148 argappend(&newfs_arg, "-d %s", optarg); 149 break; 150 case 'E': 151 path_mdconfig = optarg; 152 break; 153 case 'e': 154 argappend(&newfs_arg, "-e %s", optarg); 155 break; 156 case 'F': 157 if (have_mdtype) 158 usage(); 159 mdtype = MD_VNODE; 160 have_mdtype = true; 161 argappend(&mdconfig_arg, "-f %s", optarg); 162 break; 163 case 'f': 164 argappend(&newfs_arg, "-f %s", optarg); 165 break; 166 case 'h': 167 usage(); 168 break; 169 case 'i': 170 argappend(&newfs_arg, "-i %s", optarg); 171 break; 172 case 'L': 173 loudsubs = true; 174 break; 175 case 'l': 176 argappend(&newfs_arg, "-l"); 177 break; 178 case 'M': 179 if (have_mdtype) 180 usage(); 181 mdtype = MD_MALLOC; 182 have_mdtype = true; 183 break; 184 case 'm': 185 argappend(&newfs_arg, "-m %s", optarg); 186 break; 187 case 'N': 188 norun = true; 189 break; 190 case 'n': 191 argappend(&newfs_arg, "-n"); 192 break; 193 case 'O': 194 argappend(&newfs_arg, "-o %s", optarg); 195 break; 196 case 'o': 197 argappend(&mount_arg, "-o %s", optarg); 198 break; 199 case 'P': 200 newfs = false; 201 break; 202 case 'p': 203 if ((set = setmode(optarg)) == NULL) 204 usage(); 205 mi.mi_mode = getmode(set, S_IRWXU | S_IRWXG | S_IRWXO); 206 mi.mi_have_mode = true; 207 free(set); 208 break; 209 case 'S': 210 softdep = false; 211 break; 212 case 's': 213 argappend(&mdconfig_arg, "-s %s", optarg); 214 break; 215 case 'U': 216 softdep = true; 217 break; 218 case 'v': 219 argappend(&newfs_arg, "-O %s", optarg); 220 break; 221 case 'w': 222 extract_ugid(optarg, &mi); 223 break; 224 case 'X': 225 debug = true; 226 break; 227 default: 228 usage(); 229 } 230 argc -= optind; 231 argv += optind; 232 if (argc < 2) 233 usage(); 234 235 /* Derive 'unit' (global). */ 236 unitstr = argv[0]; 237 if (strncmp(unitstr, "/dev/", 5) == 0) 238 unitstr += 5; 239 if (strncmp(unitstr, mdname, mdnamelen) == 0) 240 unitstr += mdnamelen; 241 if (!isdigit(*unitstr)) { 242 autounit = true; 243 unit = -1; 244 mdsuffix = unitstr; 245 } else { 246 ul = strtoul(unitstr, &p, 10); 247 if (ul == ULONG_MAX) 248 errx(1, "bad device unit: %s", unitstr); 249 unit = ul; 250 mdsuffix = p; /* can be empty */ 251 } 252 253 mtpoint = argv[1]; 254 if (!have_mdtype) 255 mdtype = MD_SWAP; 256 if (softdep) 257 argappend(&newfs_arg, "-U"); 258 if (mdtype != MD_VNODE && !newfs) 259 errx(1, "-P requires a vnode-backed disk"); 260 261 /* Do the work. */ 262 if (detach && !autounit) 263 do_mdconfig_detach(); 264 if (autounit) 265 do_mdconfig_attach_au(mdconfig_arg, mdtype); 266 else 267 do_mdconfig_attach(mdconfig_arg, mdtype); 268 if (newfs) 269 do_newfs(newfs_arg); 270 do_mount(mount_arg, mtpoint); 271 do_mtptsetup(mtpoint, &mi); 272 273 return (0); 274} 275 276/* 277 * Append the expansion of 'fmt' to the buffer pointed to by '*dstp'; 278 * reallocate as required. 279 */ 280static void 281argappend(char **dstp, const char *fmt, ...) 282{ 283 char *old, *new; 284 va_list ap; 285 286 old = *dstp; 287 assert(old != NULL); 288 289 va_start(ap, fmt); 290 if (vasprintf(&new, fmt,ap) == -1) 291 errx(1, "vasprintf"); 292 va_end(ap); 293 294 *dstp = new; 295 if (asprintf(&new, "%s %s", old, new) == -1) 296 errx(1, "asprintf"); 297 free(*dstp); 298 free(old); 299 300 *dstp = new; 301} 302 303/* 304 * If run-time debugging is enabled, print the expansion of 'fmt'. 305 * Otherwise, do nothing. 306 */ 307static void 308debugprintf(const char *fmt, ...) 309{ 310 va_list ap; 311 312 if (!debug) 313 return; 314 fprintf(stderr, "DEBUG: "); 315 va_start(ap, fmt); 316 vfprintf(stderr, fmt, ap); 317 va_end(ap); 318 fprintf(stderr, "\n"); 319 fflush(stderr); 320} 321 322/* 323 * Attach a memory disk with a known unit. 324 */ 325static void 326do_mdconfig_attach(const char *args, const enum md_types mdtype) 327{ 328 int rv; 329 const char *ta; /* Type arg. */ 330 331 switch (mdtype) { 332 case MD_SWAP: 333 ta = "-t swap"; 334 break; 335 case MD_VNODE: 336 ta = "-t vnode"; 337 break; 338 case MD_MALLOC: 339 ta = "-t malloc"; 340 break; 341 default: 342 abort(); 343 } 344 rv = run(NULL, "%s -a %s%s -u %s%d", path_mdconfig, ta, args, 345 mdname, unit); 346 if (rv) 347 errx(1, "mdconfig (attach) exited with error code %d", rv); 348} 349 350/* 351 * Attach a memory disk with an unknown unit; use autounit. 352 */ 353static void 354do_mdconfig_attach_au(const char *args, const enum md_types mdtype) 355{ 356 const char *ta; /* Type arg. */ 357 char *linep, *linebuf; /* Line pointer, line buffer. */ 358 int fd; /* Standard output of mdconfig invocation. */ 359 FILE *sfd; 360 int rv; 361 char *p; 362 size_t linelen; 363 unsigned long ul; 364 365 switch (mdtype) { 366 case MD_SWAP: 367 ta = "-t swap"; 368 break; 369 case MD_VNODE: 370 ta = "-t vnode"; 371 break; 372 case MD_MALLOC: 373 ta = "-t malloc"; 374 break; 375 default: 376 abort(); 377 } 378 rv = run(&fd, "%s -a %s%s", path_mdconfig, ta, args); 379 if (rv) 380 errx(1, "mdconfig (attach) exited with error code %d", rv); 381 382 /* Receive the unit number. */ 383 if (norun) { /* Since we didn't run, we can't read. Fake it. */ 384 unit = 0; 385 return; 386 } 387 sfd = fdopen(fd, "r"); 388 if (sfd == NULL) 389 err(1, "fdopen"); 390 linep = fgetln(sfd, &linelen); 391 if (linep == NULL && linelen < mdnamelen + 1) 392 errx(1, "unexpected output from mdconfig (attach)"); 393 /* If the output format changes, we want to know about it. */ 394 assert(strncmp(linep, mdname, mdnamelen) == 0); 395 linebuf = malloc(linelen - mdnamelen + 1); 396 assert(linebuf != NULL); 397 /* Can't use strlcpy because linep is not NULL-terminated. */ 398 strncpy(linebuf, linep + mdnamelen, linelen); 399 linebuf[linelen] = '\0'; 400 ul = strtoul(linebuf, &p, 10); 401 if (ul == ULONG_MAX || *p != '\n') 402 errx(1, "unexpected output from mdconfig (attach)"); 403 unit = ul; 404 405 fclose(sfd); 406 close(fd); 407} 408 409/* 410 * Detach a memory disk. 411 */ 412static void 413do_mdconfig_detach(void) 414{ 415 int rv; 416 417 rv = run(NULL, "%s -d -u %s%d", path_mdconfig, mdname, unit); 418 if (rv && debug) /* This is allowed to fail. */ 419 warnx("mdconfig (detach) exited with error code %d (ignored)", 420 rv); 421} 422 423/* 424 * Mount the configured memory disk. 425 */ 426static void 427do_mount(const char *args, const char *mtpoint) 428{ 429 int rv; 430 431 rv = run(NULL, "%s%s /dev/%s%d%s %s", _PATH_MOUNT, args, 432 mdname, unit, mdsuffix, mtpoint); 433 if (rv) 434 errx(1, "mount exited with error code %d", rv); 435} 436 437/* 438 * Various configuration of the mountpoint. Mostly, enact 'mip'. 439 */ 440static void 441do_mtptsetup(const char *mtpoint, struct mtpt_info *mip) 442{ 443 444 if (mip->mi_have_mode) { 445 debugprintf("changing mode of %s to %o.", mtpoint, 446 mip->mi_mode); 447 if (!norun) 448 if (chmod(mtpoint, mip->mi_mode) == -1) 449 err(1, "chmod: %s", mtpoint); 450 } 451 /* 452 * We have to do these separately because the user may have 453 * only specified one of them. 454 */ 455 if (mip->mi_have_uid) { 456 debugprintf("changing owner (user) or %s to %u.", mtpoint, 457 mip->mi_uid); 458 if (!norun) 459 if (chown(mtpoint, mip->mi_uid, -1) == -1) 460 err(1, "chown %s to %u (user)", mtpoint, 461 mip->mi_uid); 462 } 463 if (mip->mi_have_gid) { 464 debugprintf("changing owner (group) or %s to %u.", mtpoint, 465 mip->mi_gid); 466 if (!norun) 467 if (chown(mtpoint, -1, mip->mi_gid) == -1) 468 err(1, "chown %s to %u (group)", mtpoint, 469 mip->mi_gid); 470 } 471} 472 473/* 474 * Put a file system on the memory disk. 475 */ 476static void 477do_newfs(const char *args) 478{ 479 int rv; 480 481 rv = run(NULL, "%s%s /dev/%s%d", _PATH_NEWFS, args, mdname, unit); 482 if (rv) 483 errx(1, "newfs exited with error code %d", rv); 484} 485 486/* 487 * 'str' should be a user and group name similar to the last argument 488 * to chown(1); i.e., a user, followed by a colon, followed by a 489 * group. The user and group in 'str' may be either a [ug]id or a 490 * name. Upon return, the uid and gid fields in 'mip' will contain 491 * the uid and gid of the user and group name in 'str', respectively. 492 * 493 * In other words, this derives a user and group id from a string 494 * formatted like the last argument to chown(1). 495 * 496 * Notice: At this point we don't support only a username or only a 497 * group name. do_mtptsetup already does, so when this feature is 498 * desired, this is the only routine that needs to be changed. 499 */ 500static void 501extract_ugid(const char *str, struct mtpt_info *mip) 502{ 503 char *ug; /* Writable 'str'. */ 504 char *user, *group; /* Result of extracton. */ 505 struct passwd *pw; 506 struct group *gr; 507 char *p; 508 uid_t *uid; 509 gid_t *gid; 510 511 uid = &mip->mi_uid; 512 gid = &mip->mi_gid; 513 mip->mi_have_uid = mip->mi_have_gid = false; 514 515 /* Extract the user and group from 'str'. Format above. */ 516 ug = strdup(str); 517 assert(ug != NULL); 518 group = ug; 519 user = strsep(&group, ":"); 520 if (user == NULL || group == NULL || *user == '\0' || *group == '\0') 521 usage(); 522 523 /* Derive uid. */ 524 *uid = strtoul(user, &p, 10); 525 if (*uid == (uid_t)ULONG_MAX) 526 usage(); 527 if (*p != '\0') { 528 pw = getpwnam(user); 529 if (pw == NULL) 530 errx(1, "invalid user: %s", user); 531 *uid = pw->pw_uid; 532 } 533 mip->mi_have_uid = true; 534 535 /* Derive gid. */ 536 *gid = strtoul(group, &p, 10); 537 if (*gid == (gid_t)ULONG_MAX) 538 usage(); 539 if (*p != '\0') { 540 gr = getgrnam(group); 541 if (gr == NULL) 542 errx(1, "invalid group: %s", group); 543 *gid = gr->gr_gid; 544 } 545 mip->mi_have_gid = true; 546 547 free(ug); 548} 549 550/* 551 * Run a process with command name and arguments pointed to by the 552 * formatted string 'cmdline'. Since system(3) is not used, the first 553 * space-delimited token of 'cmdline' must be the full pathname of the 554 * program to run. The return value is the return code of the process 555 * spawned. If 'ofd' is non-NULL, it is set to the standard output of 556 * the program spawned (i.e., you can read from ofd and get the output 557 * of the program). 558 */ 559static int 560run(int *ofd, const char *cmdline, ...) 561{ 562 char **argv, **argvp; /* Result of splitting 'cmd'. */ 563 int argc; 564 char *cmd; /* Expansion of 'cmdline'. */ 565 int pid, status; /* Child info. */ 566 int pfd[2]; /* Pipe to the child. */ 567 int nfd; /* Null (/dev/null) file descriptor. */ 568 bool dup2dn; /* Dup /dev/null to stdout? */ 569 va_list ap; 570 char *p; 571 int rv, i; 572 573 dup2dn = true; 574 va_start(ap, cmdline); 575 rv = vasprintf(&cmd, cmdline, ap); 576 if (rv == -1) 577 err(1, "vasprintf"); 578 va_end(ap); 579 580 /* Split up 'cmd' into 'argv' for use with execve. */ 581 for (argc = 1, p = cmd; (p = strchr(p, ' ')) != NULL; p++) 582 argc++; /* 'argc' generation loop. */ 583 argv = (char **)malloc(sizeof(*argv) * (argc + 1)); 584 assert(argv != NULL); 585 for (p = cmd, argvp = argv; (*argvp = strsep(&p, " ")) != NULL;) 586 if (**argvp != '\0') 587 if (++argvp >= &argv[argc]) { 588 *argvp = NULL; 589 break; 590 } 591 assert(*argv); 592 /* The argv array ends up NULL-terminated here. */ 593 594 /* Make sure the above loop works as expected. */ 595 if (debug) { 596 /* 597 * We can't, but should, use debugprintf here. First, 598 * it appends a trailing newline to the output, and 599 * second it prepends "DEBUG: " to the output. The 600 * former is a problem for this would-be first call, 601 * and the latter for the would-be call inside the 602 * loop. 603 */ 604 (void)fprintf(stderr, "DEBUG: running:"); 605 /* Should be equivilent to 'cmd' (before strsep, of course). */ 606 for (i = 0; argv[i] != NULL; i++) 607 (void)fprintf(stderr, " %s", argv[i]); 608 (void)fprintf(stderr, "\n"); 609 } 610 611 /* Create a pipe if necessary and fork the helper program. */ 612 if (ofd != NULL) { 613 if (pipe(&pfd[0]) == -1) 614 err(1, "pipe"); 615 *ofd = pfd[0]; 616 dup2dn = false; 617 } 618 pid = fork(); 619 switch (pid) { 620 case 0: 621 /* XXX can we call err() in here? */ 622 if (norun) 623 _exit(0); 624 if (ofd != NULL) 625 if (dup2(pfd[1], STDOUT_FILENO) < 0) 626 err(1, "dup2"); 627 if (!loudsubs) { 628 nfd = open(_PATH_DEVNULL, O_RDWR); 629 if (nfd == -1) 630 err(1, "open: %s", _PATH_DEVNULL); 631 if (dup2(nfd, STDIN_FILENO) < 0) 632 err(1, "dup2"); 633 if (dup2dn) 634 if (dup2(nfd, STDOUT_FILENO) < 0) 635 err(1, "dup2"); 636 if (dup2(nfd, STDERR_FILENO) < 0) 637 err(1, "dup2"); 638 } 639 640 (void)execv(argv[0], argv); 641 warn("exec: %s", argv[0]); 642 _exit(-1); 643 case -1: 644 err(1, "fork"); 645 } 646 647 free(cmd); 648 free(argv); 649 while (waitpid(pid, &status, 0) != pid) 650 ; 651 return (WEXITSTATUS(status)); 652} 653 654static void 655usage(void) 656{ 657 658 fprintf(stderr, 659"usage: %s [-DLlMNnPSUX] [-a maxcontig] [-b block-size]\n" 660"\t[-c blocks-per-cylinder-group][-d max-extent-size] [-E path-mdconfig]\n" 661"\t[-e maxbpg] [-F file] [-f frag-size] [-i bytes] [-m percent-free]\n" 662"\t[-O optimization] [-o mount-options]\n" 663"\t[-p permissions] [-s size] [-v version] [-w user:group]\n" 664"\tmd-device mount-point\n", getprogname()); 665 exit(1); 666} 667