1 /* $NetBSD: target.c,v 1.8 2019/07/23 18:13:40 martin Exp $ */ 2 3 /* 4 * Copyright 1997 Jonathan Stone 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed for the NetBSD Project by 18 * Jonathan Stone. 19 * 4. The name of Jonathan Stone may not be used to endorse 20 * or promote products derived from this software without specific prior 21 * written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY JONATHAN STONE ``AS IS'' 24 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL PIERMONT INFORMATION SYSTEMS INC. BE 27 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 28 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 29 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 30 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 31 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 32 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF 33 * THE POSSIBILITY OF SUCH DAMAGE. 34 * 35 */ 36 37 /* Copyright below applies to the realpath() code */ 38 39 /* 40 * Copyright (c) 1989, 1991, 1993, 1995 41 * The Regents of the University of California. All rights reserved. 42 * 43 * This code is derived from software contributed to Berkeley by 44 * Jan-Simon Pendry. 45 * 46 * Redistribution and use in source and binary forms, with or without 47 * modification, are permitted provided that the following conditions 48 * are met: 49 * 1. Redistributions of source code must retain the above copyright 50 * notice, this list of conditions and the following disclaimer. 51 * 2. Redistributions in binary form must reproduce the above copyright 52 * notice, this list of conditions and the following disclaimer in the 53 * documentation and/or other materials provided with the distribution. 54 * 3. Neither the name of the University nor the names of its contributors 55 * may be used to endorse or promote products derived from this software 56 * without specific prior written permission. 57 * 58 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 59 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 60 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 61 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 62 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 63 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 64 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 65 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 66 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 67 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 68 * SUCH DAMAGE. 69 */ 70 71 72 #include <sys/cdefs.h> 73 #if defined(LIBC_SCCS) && !defined(lint) 74 __RCSID("$NetBSD: target.c,v 1.8 2019/07/23 18:13:40 martin Exp $"); 75 #endif 76 77 /* 78 * target.c -- path-prefixing routines to access the target installation 79 * filesystems. Makes the install tools more independent of whether 80 * we're installing into a separate filesystem hierarchy mounted under 81 * /targetroot, or into the currently active root mounted on /. 82 */ 83 84 #include <sys/param.h> /* XXX vm_param.h always defines TRUE*/ 85 #include <sys/types.h> 86 #include <sys/sysctl.h> 87 #include <sys/stat.h> /* stat() */ 88 #include <sys/mount.h> /* statfs() */ 89 90 #include <fcntl.h> 91 #include <stdio.h> 92 #include <stdarg.h> 93 #include <unistd.h> 94 #include <curses.h> /* defines TRUE, but checks */ 95 #include <errno.h> 96 97 98 #include "defs.h" 99 #include "md.h" 100 #include "msg_defs.h" 101 #include "menu_defs.h" 102 103 /* 104 * local prototypes 105 */ 106 107 static void make_prefixed_dir (const char *prefix, const char *path); 108 static int do_target_chdir (const char *dir, int flag); 109 int target_test(unsigned int mode, const char *path); 110 int target_test_dir (const char *path); /* deprecated */ 111 int target_test_file (const char *path); /* deprecated */ 112 int target_test_symlink (const char *path); /* deprecated */ 113 114 void unwind_mounts(void); 115 116 /* Record a mount for later unwinding of target mounts. */ 117 struct unwind_mount { 118 struct unwind_mount *um_prev; 119 char um_mountpoint[4]; /* Allocated longer... */ 120 }; 121 122 /* Unwind-mount stack */ 123 struct unwind_mount *unwind_mountlist = NULL; 124 125 /* 126 * Debugging options 127 */ 128 /*#define DEBUG_ROOT*/ /* turn on what-is-root? debugging. */ 129 /*#define DEBUG_UNWIND*/ /* turn on unwind-target-mount debugging. */ 130 131 /* 132 * debugging helper. curses... 133 */ 134 #if defined(DEBUG) || defined(DEBUG_ROOT) 135 void 136 backtowin(void) 137 { 138 139 fflush(stdout); /* curses does not leave stdout linebuffered. */ 140 getchar(); /* wait for user to press return */ 141 wrefresh(stdscr); 142 } 143 #endif 144 145 146 /* 147 * Is the root partition we're running from the same as the root 148 * which the user has selected to install/upgrade? 149 * Uses global variable "pm->diskdev" to find the selected device for 150 * install/upgrade. 151 */ 152 int 153 target_already_root(void) 154 { 155 char dev[PATH_MAX]; 156 int rootpart = -1; 157 static struct pm_devs *last_pm; 158 static int last_res; 159 part_id ptn; 160 struct disk_partitions *parts; 161 struct disk_part_info info; 162 163 if (pm == last_pm) 164 return last_res; 165 166 if (pm->cur_system) 167 return 1; 168 169 last_pm = pm; 170 last_res = 0; 171 172 parts = pm->parts; 173 if (parts == NULL) { 174 last_res = 0; 175 return 0; 176 } 177 178 if (pm->no_part) { 179 last_res = is_active_rootpart(pm->diskdev, -1); 180 return last_res; 181 } 182 183 if (pm->parts->pscheme->secondary_partitions != NULL) 184 parts = pm->parts->pscheme->secondary_partitions(parts, 185 pm->ptstart, false); 186 187 for (ptn = 0; ptn < parts->num_part; ptn++) { 188 if (!parts->pscheme->get_part_info(parts, ptn, &info)) 189 continue; 190 if (info.nat_type->generic_ptype != PT_root) 191 continue; 192 if (!is_root_part_mount(info.last_mounted)) 193 continue; 194 if (!parts->pscheme->get_part_device(parts, ptn, 195 dev, sizeof dev, &rootpart, plain_name, false)) 196 continue; 197 198 last_res = is_active_rootpart(dev, rootpart); 199 break; 200 } 201 202 return last_res; 203 } 204 205 /* 206 * Could something with this "last mounted on" information be a potential 207 * root partition? 208 */ 209 bool 210 is_root_part_mount(const char *last_mounted) 211 { 212 return strcmp(last_mounted, "/") == 0 || 213 strcmp(last_mounted, "/targetroot") == 0 || 214 strcmp(last_mounted, "/altroot") == 0; 215 } 216 217 /* 218 * Is this device partition (e.g., "sd0a") mounted as root? 219 */ 220 int 221 is_active_rootpart(const char *dev, int ptn) 222 { 223 int mib[2]; 224 char rootdev[SSTRSIZE]; 225 int rootptn; 226 size_t varlen; 227 228 mib[0] = CTL_KERN; 229 mib[1] = KERN_ROOT_DEVICE; 230 varlen = sizeof(rootdev); 231 if (sysctl(mib, 2, rootdev, &varlen, NULL, 0) < 0) 232 return 1; 233 234 if (strcmp(dev, rootdev) != 0) 235 return 0; 236 237 if (ptn < 0) 238 return 1; /* device only check, or wedge */ 239 240 mib[1] = KERN_ROOT_PARTITION; 241 varlen = sizeof rootptn; 242 rootptn = -1; 243 if (sysctl(mib, 2, &rootptn, &varlen, NULL, 0) < 0) 244 return 1; 245 246 return ptn == rootptn; 247 } 248 249 /* 250 * Pathname prefixing glue to support installation either 251 * from in-ramdisk miniroots or on-disk diskimages. 252 * If our root is on the target disk, the install target is mounted 253 * on /targetroot and we need to prefix installed pathnames with /targetroot. 254 * otherwise we are installing to the currently-active root and 255 * no prefix is needed. 256 */ 257 const char * 258 target_prefix(void) 259 { 260 /* 261 * XXX fetch sysctl variable for current root, and compare 262 * to the devicename of the install target disk. 263 */ 264 return(target_already_root() ? "" : targetroot_mnt); 265 } 266 267 /* 268 * concatenate two pathnames. 269 * XXX returns either input args or result in a static buffer. 270 * The caller must copy if it wants to use the pathname past the 271 * next call to a target-prefixing function, or to modify the inputs.. 272 * Used only internally so this is probably safe. 273 */ 274 const char * 275 concat_paths(const char *prefix, const char *suffix) 276 { 277 static char real_path[MAXPATHLEN]; 278 279 /* absolute prefix and null suffix? */ 280 if (prefix[0] == '/' && suffix[0] == 0) 281 return prefix; 282 283 /* null prefix and absolute suffix? */ 284 if (prefix[0] == 0 && suffix[0] == '/') 285 return suffix; 286 287 /* avoid "//" */ 288 if (suffix[0] == '/' || suffix[0] == 0) 289 snprintf(real_path, sizeof(real_path), "%s%s", prefix, suffix); 290 else 291 snprintf(real_path, sizeof(real_path), "%s/%s", 292 prefix, suffix); 293 return (real_path); 294 } 295 296 /* 297 * Do target prefix expansion on a pathname. 298 * XXX uses concat_paths and so returns result in a static buffer. 299 * The caller must copy if it wants to use the pathname past the 300 * next call to a target-prefixing function, or to modify the inputs.. 301 * Used only internally so this is probably safe. 302 * 303 * Not static so other functions can generate target related file names. 304 */ 305 const char * 306 target_expand(const char *tgtpath) 307 { 308 309 return concat_paths(target_prefix(), tgtpath); 310 } 311 312 /* Make a directory, with a prefix like "/targetroot" or possibly just "". */ 313 static void 314 make_prefixed_dir(const char *prefix, const char *path) 315 { 316 317 run_program(0, "/bin/mkdir -p %s", concat_paths(prefix, path)); 318 } 319 320 /* Make a directory with a pathname relative to the installation target. */ 321 void 322 make_target_dir(const char *path) 323 { 324 325 make_prefixed_dir(target_prefix(), path); 326 } 327 328 329 static int 330 do_target_chdir(const char *dir, int must_succeed) 331 { 332 const char *tgt_dir; 333 int error; 334 335 error = 0; 336 tgt_dir = target_expand(dir); 337 338 #ifdef DEBUG 339 printf("target_chdir (%s)\n", tgt_dir); 340 //return (0); 341 #endif 342 /* chdir returns -1 on error and sets errno. */ 343 if (chdir(tgt_dir) < 0) 344 error = errno; 345 if (logfp) { 346 fprintf(logfp, "cd to %s\n", tgt_dir); 347 fflush(logfp); 348 } 349 if (script) { 350 scripting_fprintf(NULL, "cd %s\n", tgt_dir); 351 fflush(script); 352 } 353 354 if (error && must_succeed) { 355 const char *args[] = { target_prefix(), strerror(error) }; 356 char *err = str_arg_subst(msg_string(MSG_realdir), 357 __arraycount(args), args); 358 fprintf(stderr, "%s\n", err); 359 if (logfp) 360 fprintf(logfp, "%s\n", err); 361 free(err); 362 exit(1); 363 } 364 errno = error; 365 return (error); 366 } 367 368 void 369 target_chdir_or_die(const char *dir) 370 { 371 372 (void)do_target_chdir(dir, 1); 373 } 374 375 #ifdef notdef 376 int 377 target_chdir(const char *dir) 378 { 379 380 return do_target_chdir(dir, 0); 381 } 382 #endif 383 384 /* 385 * Copy a file from the current root into the target system, 386 * where the destination pathname is relative to the target root. 387 * Does not check for copy-to-self when target is current root. 388 */ 389 int 390 cp_to_target(const char *srcpath, const char *tgt_path) 391 { 392 const char *real_path = target_expand(tgt_path); 393 394 return run_program(0, "/bin/cp %s %s", srcpath, real_path); 395 } 396 397 /* 398 * Duplicate a file from the current root to the same pathname 399 * in the target system. Pathname must be an absolute pathname. 400 * If we're running in the target, do nothing. 401 */ 402 void 403 dup_file_into_target(const char *filename) 404 { 405 406 if (!target_already_root()) 407 cp_to_target(filename, filename); 408 } 409 410 411 /* 412 * Do a mv where both pathnames are within the target filesystem. 413 */ 414 void 415 mv_within_target_or_die(const char *frompath, const char *topath) 416 { 417 char realfrom[STRSIZE]; 418 char realto[STRSIZE]; 419 420 strlcpy(realfrom, target_expand(frompath), sizeof realfrom); 421 strlcpy(realto, target_expand(topath), sizeof realto); 422 423 run_program(RUN_FATAL, "mv %s %s", realfrom, realto); 424 } 425 426 /* Do a cp where both pathnames are within the target filesystem. */ 427 int 428 cp_within_target(const char *frompath, const char *topath, int optional) 429 { 430 char realfrom[STRSIZE]; 431 char realto[STRSIZE]; 432 433 strncpy(realfrom, target_expand(frompath), STRSIZE); 434 strncpy(realto, target_expand(topath), STRSIZE); 435 436 if (access(realfrom, R_OK) == -1 && optional) 437 return 0; 438 return (run_program(0, "cp -p %s %s", realfrom, realto)); 439 } 440 441 /* fopen a pathname in the target. */ 442 FILE * 443 target_fopen(const char *filename, const char *type) 444 { 445 446 return fopen(target_expand(filename), type); 447 } 448 449 /* 450 * Do a mount onto a mountpoint in the install target. 451 * Record mountpoint so we can unmount when finished. 452 * NB: does not prefix mount-from, which probably breaks nullfs mounts. 453 */ 454 int 455 target_mount_do(const char *opts, const char *from, const char *on) 456 { 457 struct unwind_mount *m; 458 int error; 459 int len; 460 461 len = strlen(on); 462 m = malloc(sizeof *m + len); 463 if (m == 0) 464 return (ENOMEM); /* XXX */ 465 466 memcpy(m->um_mountpoint, on, len + 1); 467 468 #ifdef DEBUG_UNWIND 469 endwin(); 470 fprintf(stderr, "mounting %s with unwind\n", on); 471 backtowin(); 472 #endif 473 474 error = run_program(0, "/sbin/mount %s %s %s%s", 475 opts, from, target_prefix(), on); 476 if (error) { 477 free(m); 478 return error; 479 } 480 m->um_prev = unwind_mountlist; 481 unwind_mountlist = m; 482 return 0; 483 } 484 485 int 486 target_mount(const char *opts, const char *from, const char *on) 487 { 488 return target_mount_do(opts, from, on); 489 } 490 491 /* 492 * unwind the mount stack, unmounting mounted filesystems. 493 * For now, ignore any errors in unmount. 494 * (Why would we be unable to unmount? The user has suspended 495 * us and forked shell sitting somewhere in the target root?) 496 */ 497 void 498 unwind_mounts(void) 499 { 500 struct unwind_mount *m; 501 static volatile int unwind_in_progress = 0; 502 503 /* signal safety */ 504 if (unwind_in_progress) 505 return; 506 unwind_in_progress = 1; 507 508 while ((m = unwind_mountlist) != NULL) { 509 unwind_mountlist = m->um_prev; 510 #ifdef DEBUG_UNWIND 511 endwin(); 512 fprintf(stderr, "unmounting %s\n", m->um_mountpoint); 513 backtowin(); 514 #endif 515 run_program(0, "/sbin/umount %s%s", 516 target_prefix(), m->um_mountpoint); 517 free(m); 518 } 519 unwind_in_progress = 0; 520 } 521 522 int 523 target_collect_file(int kind, char **buffer, const char *name) 524 { 525 const char *realname = target_expand(name); 526 527 #ifdef DEBUG 528 printf("collect real name %s\n", realname); 529 #endif 530 return collect(kind, buffer, "%s", realname); 531 } 532 533 /* 534 * Verify a pathname already exists in the target root filesystem, 535 * by running test "testflag" on the expanded target pathname. 536 */ 537 int 538 target_test(unsigned int mode, const char *path) 539 { 540 const char *real_path = target_expand(path); 541 register int result; 542 543 result = !file_mode_match(real_path, mode); 544 scripting_fprintf(NULL, "if [ $? != 0 ]; then echo \"%s does not exist!\"; fi\n", real_path); 545 546 #if defined(DEBUG) 547 printf("target_test(%o, %s) returning %d\n", mode, real_path, result); 548 #endif 549 return (result); 550 } 551 552 /* 553 * Verify a directory already exists in the target root 554 * filesystem. Do not create the directory if it doesn't exist. 555 * Assumes that sysinst has already mounted the target root. 556 */ 557 int 558 target_test_dir(const char *path) 559 { 560 561 return target_test(S_IFDIR, path); 562 } 563 564 /* 565 * Verify an ordinary file already exists in the target root 566 * filesystem. Do not create the directory if it doesn't exist. 567 * Assumes that sysinst has already mounted the target root. 568 */ 569 int 570 target_test_file(const char *path) 571 { 572 573 return target_test(S_IFREG, path); 574 } 575 576 int 577 target_test_symlink(const char *path) 578 { 579 580 return target_test(S_IFLNK, path); 581 } 582 583 int 584 target_file_exists_p(const char *path) 585 { 586 587 return (target_test_file(path) == 0); 588 } 589 590 int 591 target_dir_exists_p(const char *path) 592 { 593 594 return (target_test_dir(path) == 0); 595 } 596 597 int 598 target_symlink_exists_p(const char *path) 599 { 600 601 return (target_test_symlink(path) == 0); 602 } 603 604 int 605 target_mounted(void) 606 { 607 return (unwind_mountlist != NULL); 608 } 609