usr.sbin/makefs/mtree.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
   3  *
   4  * Copyright (c) 2011 Marcel Moolenaar
   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  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
  17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  19  * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
  20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  26  */
  27
  28 #include <sys/cdefs.h>
  29 __FBSDID("$FreeBSD$");
  30
  31 #include <sys/param.h>
  32 #include <sys/queue.h>
  33 #include <sys/sbuf.h>
  34 #include <sys/stat.h>
  35 #include <sys/types.h>
  36 #include <assert.h>
  37 #include <errno.h>
  38 #include <fcntl.h>
  39 #include <grp.h>
  40 #include <inttypes.h>
  41 #include <pwd.h>
  42 #include <stdarg.h>
  43 #include <stdbool.h>
  44 #include <stddef.h>
  45 #include <stdio.h>
  46 #include <stdlib.h>
  47 #include <string.h>
  48 #include <strings.h>
  49 #include <time.h>
  50 #include <unistd.h>
  51 #include <util.h>
  52 #include <vis.h>
  53
  54 #include "makefs.h"
  55
  56 #ifndef ENOATTR
  57 #define ENOATTR ENOMSG
  58 #endif
  59
  60 #define IS_DOT(nm)      ((nm)[0] == '.' && (nm)[1] == '\0')
  61 #define IS_DOTDOT(nm)   ((nm)[0] == '.' && (nm)[1] == '.' && (nm)[2] == '\0')
  62
  63 struct mtree_fileinfo {
  64         SLIST_ENTRY(mtree_fileinfo) next;
  65         FILE *fp;
  66         const char *name;
  67         u_int line;
  68 };
  69
  70 /* Global state used while parsing. */
  71 static SLIST_HEAD(, mtree_fileinfo) mtree_fileinfo =
  72     SLIST_HEAD_INITIALIZER(mtree_fileinfo);
  73 static fsnode *mtree_root;
  74 static fsnode *mtree_current;
  75 static fsnode mtree_global;
  76 static fsinode mtree_global_inode;
  77 static u_int errors, warnings;
  78
  79 static void mtree_error(const char *, ...) __printflike(1, 2);
  80 static void mtree_warning(const char *, ...) __printflike(1, 2);
  81
  82 static int
  83 mtree_file_push(const char *name, FILE *fp)
  84 {
  85         struct mtree_fileinfo *fi;
  86
  87         fi = emalloc(sizeof(*fi));
  88         if (strcmp(name, "-") == 0)
  89                 fi->name = estrdup("(stdin)");
  90         else
  91                 fi->name = estrdup(name);
  92         if (fi->name == NULL) {
  93                 free(fi);
  94                 return (ENOMEM);
  95         }
  96
  97         fi->fp = fp;
  98         fi->line = 0;
  99
 100         SLIST_INSERT_HEAD(&mtree_fileinfo, fi, next);
 101         return (0);
 102 }
 103
 104 static void
 105 mtree_print(const char *msgtype, const char *fmt, va_list ap)
 106 {
 107         struct mtree_fileinfo *fi;
 108
 109         if (msgtype != NULL) {
 110                 fi = SLIST_FIRST(&mtree_fileinfo);
 111                 if (fi != NULL)
 112                         fprintf(stderr, "%s:%u: ", fi->name, fi->line);
 113                 fprintf(stderr, "%s: ", msgtype);
 114         }
 115         vfprintf(stderr, fmt, ap);
 116 }
 117
 118 static void
 119 mtree_error(const char *fmt, ...)
 120 {
 121         va_list ap;
 122
 123         va_start(ap, fmt);
 124         mtree_print("error", fmt, ap);
 125         va_end(ap);
 126
 127         errors++;
 128         fputc('\n', stderr);
 129 }
 130
 131 static void
 132 mtree_warning(const char *fmt, ...)
 133 {
 134         va_list ap;
 135
 136         va_start(ap, fmt);
 137         mtree_print("warning", fmt, ap);
 138         va_end(ap);
 139
 140         warnings++;
 141         fputc('\n', stderr);
 142 }
 143
 144 #ifndef MAKEFS_MAX_TREE_DEPTH
 145 # define MAKEFS_MAX_TREE_DEPTH (MAXPATHLEN/2)
 146 #endif
 147
 148 /* construct path to node->name */
 149 static char *
 150 mtree_file_path(fsnode *node)
 151 {
 152         fsnode *pnode;
 153         struct sbuf *sb;
 154         char *res, *rp[MAKEFS_MAX_TREE_DEPTH];
 155         int depth;
 156
 157         depth = 0;
 158         rp[depth] = node->name;
 159         for (pnode = node->parent; pnode && depth < MAKEFS_MAX_TREE_DEPTH - 1;
 160              pnode = pnode->parent) {
 161                 if (strcmp(pnode->name, ".") == 0)
 162                         break;
 163                 rp[++depth] = pnode->name;
 164         }
 165
 166         sb = sbuf_new_auto();
 167         if (sb == NULL) {
 168                 errno = ENOMEM;
 169                 return (NULL);
 170         }
 171         while (depth > 0) {
 172                 sbuf_cat(sb, rp[depth--]);
 173                 sbuf_putc(sb, '/');
 174         }
 175         sbuf_cat(sb, rp[depth]);
 176         sbuf_finish(sb);
 177         res = estrdup(sbuf_data(sb));
 178         sbuf_delete(sb);
 179         if (res == NULL)
 180                 errno = ENOMEM;
 181         return res;
 182
 183 }
 184
 185 /* mtree_resolve() sets errno to indicate why NULL was returned. */
 186 static char *
 187 mtree_resolve(const char *spec, int *istemp)
 188 {
 189         struct sbuf *sb;
 190         char *res, *var = NULL;
 191         const char *base, *p, *v;
 192         size_t len;
 193         int c, error, quoted, subst;
 194
 195         len = strlen(spec);
 196         if (len == 0) {
 197                 errno = EINVAL;
 198                 return (NULL);
 199         }
 200
 201         c = (len > 1) ? (spec[0] == spec[len - 1]) ? spec[0] : 0 : 0;
 202         *istemp = (c == '`') ? 1 : 0;
 203         subst = (c == '`' || c == '"') ? 1 : 0;
 204         quoted = (subst || c == '\'') ? 1 : 0;
 205
 206         if (!subst) {
 207                 res = estrdup(spec + quoted);
 208                 if (quoted)
 209                         res[len - 2] = '\0';
 210                 return (res);
 211         }
 212
 213         sb = sbuf_new_auto();
 214         if (sb == NULL) {
 215                 errno = ENOMEM;
 216                 return (NULL);
 217         }
 218
 219         base = spec + 1;
 220         len -= 2;
 221         error = 0;
 222         while (len > 0) {
 223                 p = strchr(base, '$');
 224                 if (p == NULL) {
 225                         sbuf_bcat(sb, base, len);
 226                         base += len;
 227                         len = 0;
 228                         continue;
 229                 }
 230                 /* The following is safe. spec always starts with a quote. */
 231                 if (p[-1] == '\\')
 232                         p--;
 233                 if (base != p) {
 234                         sbuf_bcat(sb, base, p - base);
 235                         len -= p - base;
 236                         base = p;
 237                 }
 238                 if (*p == '\\') {
 239                         sbuf_putc(sb, '$');
 240                         base += 2;
 241                         len -= 2;
 242                         continue;
 243                 }
 244                 /* Skip the '$'. */
 245                 base++;
 246                 len--;
 247                 /* Handle ${X} vs $X. */
 248                 v = base;
 249                 if (*base == '{') {
 250                         p = strchr(v, '}');
 251                         if (p == NULL)
 252                                 p = v;
 253                 } else
 254                         p = v;
 255                 len -= (p + 1) - base;
 256                 base = p + 1;
 257
 258                 if (v == p) {
 259                         sbuf_putc(sb, *v);
 260                         continue;
 261                 }
 262
 263                 error = ENOMEM;
 264                 var = ecalloc(p - v, 1);
 265                 memcpy(var, v + 1, p - v - 1);
 266                 if (strcmp(var, ".CURDIR") == 0) {
 267                         res = getcwd(NULL, 0);
 268                         if (res == NULL)
 269                                 break;
 270                 } else if (strcmp(var, ".PROG") == 0) {
 271                         res = estrdup(getprogname());
 272                 } else {
 273                         v = getenv(var);
 274                         if (v != NULL) {
 275                                 res = estrdup(v);
 276                         } else
 277                                 res = NULL;
 278                 }
 279                 error = 0;
 280
 281                 if (res != NULL) {
 282                         sbuf_cat(sb, res);
 283                         free(res);
 284                 }
 285                 free(var);
 286                 var = NULL;
 287         }
 288
 289         free(var);
 290         sbuf_finish(sb);
 291         res = (error == 0) ? strdup(sbuf_data(sb)) : NULL;
 292         sbuf_delete(sb);
 293         if (res == NULL)
 294                 errno = ENOMEM;
 295         return (res);
 296 }
 297
 298 static int
 299 skip_over(FILE *fp, const char *cs)
 300 {
 301         int c;
 302
 303         c = getc(fp);
 304         while (c != EOF && strchr(cs, c) != NULL)
 305                 c = getc(fp);
 306         if (c != EOF) {
 307                 ungetc(c, fp);
 308                 return (0);
 309         }
 310         return (ferror(fp) ? errno : -1);
 311 }
 312
 313 static int
 314 skip_to(FILE *fp, const char *cs)
 315 {
 316         int c;
 317
 318         c = getc(fp);
 319         while (c != EOF && strchr(cs, c) == NULL)
 320                 c = getc(fp);
 321         if (c != EOF) {
 322                 ungetc(c, fp);
 323                 return (0);
 324         }
 325         return (ferror(fp) ? errno : -1);
 326 }
 327
 328 static int
 329 read_word(FILE *fp, char *buf, size_t bufsz)
 330 {
 331         struct mtree_fileinfo *fi;
 332         size_t idx, qidx;
 333         int c, done, error, esc, qlvl;
 334
 335         if (bufsz == 0)
 336                 return (EINVAL);
 337
 338         done = 0;
 339         esc = 0;
 340         idx = 0;
 341         qidx = -1;
 342         qlvl = 0;
 343         do {
 344                 c = getc(fp);
 345                 switch (c) {
 346                 case EOF:
 347                         buf[idx] = '\0';
 348                         error = ferror(fp) ? errno : -1;
 349                         if (error == -1)
 350                                 mtree_error("unexpected end of file");
 351                         return (error);
 352                 case '#':               /* comment -- skip to end of line. */
 353                         if (!esc) {
 354                                 error = skip_to(fp, "\n");
 355                                 if (!error)
 356                                         continue;
 357                         }
 358                         break;
 359                 case '\\':
 360                         esc++;
 361                         break;
 362                 case '`':
 363                 case '\'':
 364                 case '"':
 365                         if (esc)
 366                                 break;
 367                         if (qlvl == 0) {
 368                                 qlvl++;
 369                                 qidx = idx;
 370                         } else if (c == buf[qidx]) {
 371                                 qlvl--;
 372                                 if (qlvl > 0) {
 373                                         do {
 374                                                 qidx--;
 375                                         } while (buf[qidx] != '`' &&
 376                                             buf[qidx] != '\'' &&
 377                                             buf[qidx] != '"');
 378                                 } else
 379                                         qidx = -1;
 380                         } else {
 381                                 qlvl++;
 382                                 qidx = idx;
 383                         }
 384                         break;
 385                 case ' ':
 386                 case '\t':
 387                 case '\n':
 388                         if (!esc && qlvl == 0) {
 389                                 ungetc(c, fp);
 390                                 c = '\0';
 391                                 done = 1;
 392                                 break;
 393                         }
 394                         if (c == '\n') {
 395                                 /*
 396                                  * We going to eat the newline ourselves.
 397                                  */
 398                                 if (qlvl > 0)
 399                                         mtree_warning("quoted word straddles "
 400                                             "onto next line.");
 401                                 fi = SLIST_FIRST(&mtree_fileinfo);
 402                                 fi->line++;
 403                         }
 404                         break;
 405                 default:
 406                         if (esc)
 407                                 buf[idx++] = '\\';
 408                         break;
 409                 }
 410                 buf[idx++] = c;
 411                 esc = 0;
 412         } while (idx < bufsz && !done);
 413
 414         if (idx >= bufsz) {
 415                 mtree_error("word too long to fit buffer (max %zu characters)",
 416                     bufsz);
 417                 skip_to(fp, " \t\n");
 418         }
 419         return (0);
 420 }
 421
 422 static fsnode *
 423 create_node(const char *name, u_int type, fsnode *parent, fsnode *global)
 424 {
 425         fsnode *n;
 426
 427         n = ecalloc(1, sizeof(*n));
 428         n->name = estrdup(name);
 429         n->type = (type == 0) ? global->type : type;
 430         n->parent = parent;
 431
 432         n->inode = ecalloc(1, sizeof(*n->inode));
 433
 434         /* Assign global options/defaults. */
 435         memcpy(n->inode, global->inode, sizeof(*n->inode));
 436         n->inode->st.st_mode = (n->inode->st.st_mode & ~S_IFMT) | n->type;
 437
 438         if (n->type == S_IFLNK)
 439                 n->symlink = global->symlink;
 440         else if (n->type == S_IFREG)
 441                 n->contents = global->contents;
 442
 443         return (n);
 444 }
 445
 446 static void
 447 destroy_node(fsnode *n)
 448 {
 449
 450         assert(n != NULL);
 451         assert(n->name != NULL);
 452         assert(n->inode != NULL);
 453
 454         free(n->inode);
 455         free(n->name);
 456         free(n);
 457 }
 458
 459 static int
 460 read_number(const char *tok, u_int base, intmax_t *res, intmax_t min,
 461     intmax_t max)
 462 {
 463         char *end;
 464         intmax_t val;
 465
 466         val = strtoimax(tok, &end, base);
 467         if (end == tok || end[0] != '\0')
 468                 return (EINVAL);
 469         if (val < min || val > max)
 470                 return (EDOM);
 471         *res = val;
 472         return (0);
 473 }
 474
 475 static int
 476 read_mtree_keywords(FILE *fp, fsnode *node)
 477 {
 478         char keyword[PATH_MAX];
 479         char *name, *p, *value;
 480         gid_t gid;
 481         uid_t uid;
 482         struct stat *st, sb;
 483         intmax_t num;
 484         u_long flset, flclr;
 485         int error, istemp;
 486         uint32_t type;
 487
 488         st = &node->inode->st;
 489         do {
 490                 error = skip_over(fp, " \t");
 491                 if (error)
 492                         break;
 493
 494                 error = read_word(fp, keyword, sizeof(keyword));
 495                 if (error)
 496                         break;
 497
 498                 if (keyword[0] == '\0')
 499                         break;
 500
 501                 value = strchr(keyword, '=');
 502                 if (value != NULL)
 503                         *value++ = '\0';
 504
 505                 /*
 506                  * We use EINVAL, ENOATTR, ENOSYS and ENXIO to signal
 507                  * certain conditions:
 508                  *   EINVAL -   Value provided for a keyword that does
 509                  *              not take a value. The value is ignored.
 510                  *   ENOATTR -  Value missing for a keyword that needs
 511                  *              a value. The keyword is ignored.
 512                  *   ENOSYS -   Unsupported keyword encountered. The
 513                  *              keyword is ignored.
 514                  *   ENXIO -    Value provided for a keyword that does
 515                  *              not take a value. The value is ignored.
 516                  */
 517                 switch (keyword[0]) {
 518                 case 'c':
 519                         if (strcmp(keyword, "contents") == 0) {
 520                                 if (value == NULL) {
 521                                         error = ENOATTR;
 522                                         break;
 523                                 }
 524                                 node->contents = estrdup(value);
 525                         } else
 526                                 error = ENOSYS;
 527                         break;
 528                 case 'f':
 529                         if (strcmp(keyword, "flags") == 0) {
 530                                 if (value == NULL) {
 531                                         error = ENOATTR;
 532                                         break;
 533                                 }
 534                                 flset = flclr = 0;
 535                                 if (!strtofflags(&value, &flset, &flclr)) {
 536                                         st->st_flags &= ~flclr;
 537                                         st->st_flags |= flset;
 538                                 } else
 539                                         error = errno;
 540                         } else
 541                                 error = ENOSYS;
 542                         break;
 543                 case 'g':
 544                         if (strcmp(keyword, "gid") == 0) {
 545                                 if (value == NULL) {
 546                                         error = ENOATTR;
 547                                         break;
 548                                 }
 549                                 error = read_number(value, 10, &num,
 550                                     0, UINT_MAX);
 551                                 if (!error)
 552                                         st->st_gid = num;
 553                         } else if (strcmp(keyword, "gname") == 0) {
 554                                 if (value == NULL) {
 555                                         error = ENOATTR;
 556                                         break;
 557                                 }
 558                                 if (gid_from_group(value, &gid) == 0)
 559                                         st->st_gid = gid;
 560                                 else
 561                                         error = EINVAL;
 562                         } else
 563                                 error = ENOSYS;
 564                         break;
 565                 case 'l':
 566                         if (strcmp(keyword, "link") == 0) {
 567                                 if (value == NULL) {
 568                                         error = ENOATTR;
 569                                         break;
 570                                 }
 571                                 node->symlink = emalloc(strlen(value) + 1);
 572                                 if (node->symlink == NULL) {
 573                                         error = errno;
 574                                         break;
 575                                 }
 576                                 if (strunvis(node->symlink, value) < 0) {
 577                                         error = errno;
 578                                         break;
 579                                 }
 580                         } else
 581                                 error = ENOSYS;
 582                         break;
 583                 case 'm':
 584                         if (strcmp(keyword, "mode") == 0) {
 585                                 if (value == NULL) {
 586                                         error = ENOATTR;
 587                                         break;
 588                                 }
 589                                 if (value[0] >= '0' && value[0] <= '9') {
 590                                         error = read_number(value, 8, &num,
 591                                             0, 07777);
 592                                         if (!error) {
 593                                                 st->st_mode &= S_IFMT;
 594                                                 st->st_mode |= num;
 595                                         }
 596                                 } else {
 597                                         /* Symbolic mode not supported. */
 598                                         error = EINVAL;
 599                                         break;
 600                                 }
 601                         } else
 602                                 error = ENOSYS;
 603                         break;
 604                 case 'o':
 605                         if (strcmp(keyword, "optional") == 0) {
 606                                 if (value != NULL)
 607                                         error = ENXIO;
 608                                 node->flags |= FSNODE_F_OPTIONAL;
 609                         } else
 610                                 error = ENOSYS;
 611                         break;
 612                 case 's':
 613                         if (strcmp(keyword, "size") == 0) {
 614                                 if (value == NULL) {
 615                                         error = ENOATTR;
 616                                         break;
 617                                 }
 618                                 error = read_number(value, 10, &num,
 619                                     0, INTMAX_MAX);
 620                                 if (!error)
 621                                         st->st_size = num;
 622                         } else
 623                                 error = ENOSYS;
 624                         break;
 625                 case 't':
 626                         if (strcmp(keyword, "time") == 0) {
 627                                 if (value == NULL) {
 628                                         error = ENOATTR;
 629                                         break;
 630                                 }
 631                                 p = strchr(value, '.');
 632                                 if (p != NULL)
 633                                         *p++ = '\0';
 634                                 error = read_number(value, 10, &num, 0,
 635                                     INTMAX_MAX);
 636                                 if (error)
 637                                         break;
 638                                 st->st_atime = num;
 639                                 st->st_ctime = num;
 640                                 st->st_mtime = num;
 641                                 if (p == NULL)
 642                                         break;
 643                                 error = read_number(p, 10, &num, 0,
 644                                     INTMAX_MAX);
 645                                 if (error)
 646                                         break;
 647                                 if (num != 0)
 648                                         error = EINVAL;
 649                         } else if (strcmp(keyword, "type") == 0) {
 650                                 if (value == NULL) {
 651                                         error = ENOATTR;
 652                                         break;
 653                                 }
 654                                 if (strcmp(value, "dir") == 0)
 655                                         node->type = S_IFDIR;
 656                                 else if (strcmp(value, "file") == 0)
 657                                         node->type = S_IFREG;
 658                                 else if (strcmp(value, "link") == 0)
 659                                         node->type = S_IFLNK;
 660                                 else
 661                                         error = EINVAL;
 662                         } else
 663                                 error = ENOSYS;
 664                         break;
 665                 case 'u':
 666                         if (strcmp(keyword, "uid") == 0) {
 667                                 if (value == NULL) {
 668                                         error = ENOATTR;
 669                                         break;
 670                                 }
 671                                 error = read_number(value, 10, &num,
 672                                     0, UINT_MAX);
 673                                 if (!error)
 674                                         st->st_uid = num;
 675                         } else if (strcmp(keyword, "uname") == 0) {
 676                                 if (value == NULL) {
 677                                         error = ENOATTR;
 678                                         break;
 679                                 }
 680                                 if (uid_from_user(value, &uid) == 0)
 681                                         st->st_uid = uid;
 682                                 else
 683                                         error = EINVAL;
 684                         } else
 685                                 error = ENOSYS;
 686                         break;
 687                 default:
 688                         error = ENOSYS;
 689                         break;
 690                 }
 691
 692                 switch (error) {
 693                 case EINVAL:
 694                         mtree_error("%s: invalid value '%s'", keyword, value);
 695                         break;
 696                 case ENOATTR:
 697                         mtree_error("%s: keyword needs a value", keyword);
 698                         break;
 699                 case ENOSYS:
 700                         mtree_warning("%s: unsupported keyword", keyword);
 701                         break;
 702                 case ENXIO:
 703                         mtree_error("%s: keyword does not take a value",
 704                             keyword);
 705                         break;
 706                 }
 707         } while (1);
 708
 709         if (error)
 710                 return (error);
 711
 712         st->st_mode = (st->st_mode & ~S_IFMT) | node->type;
 713
 714         /* Nothing more to do for the global defaults. */
 715         if (node->name == NULL)
 716                 return (0);
 717
 718         /*
 719          * Be intelligent about the file type.
 720          */
 721         if (node->contents != NULL) {
 722                 if (node->symlink != NULL) {
 723                         mtree_error("%s: both link and contents keywords "
 724                             "defined", node->name);
 725                         return (0);
 726                 }
 727                 type = S_IFREG;
 728         } else if (node->type != 0) {
 729                 type = node->type;
 730                 if (type == S_IFREG) {
 731                         /* the named path is the default contents */
 732                         node->contents = mtree_file_path(node);
 733                 }
 734         } else
 735                 type = (node->symlink != NULL) ? S_IFLNK : S_IFDIR;
 736
 737         if (node->type == 0)
 738                 node->type = type;
 739
 740         if (node->type != type) {
 741                 mtree_error("%s: file type and defined keywords to not match",
 742                     node->name);
 743                 return (0);
 744         }
 745
 746         st->st_mode = (st->st_mode & ~S_IFMT) | node->type;
 747
 748         if (node->contents == NULL)
 749                 return (0);
 750
 751         name = mtree_resolve(node->contents, &istemp);
 752         if (name == NULL)
 753                 return (errno);
 754
 755         if (stat(name, &sb) != 0) {
 756                 mtree_error("%s: contents file '%s' not found", node->name,
 757                     name);
 758                 free(name);
 759                 return (0);
 760         }
 761
 762         /*
 763          * Check for hardlinks. If the contents key is used, then the check
 764          * will only trigger if the contents file is a link even if it is used
 765          * by more than one file
 766          */
 767         if (sb.st_nlink > 1) {
 768                 fsinode *curino;
 769
 770                 st->st_ino = sb.st_ino;
 771                 st->st_dev = sb.st_dev;
 772                 curino = link_check(node->inode);
 773                 if (curino != NULL) {
 774                         free(node->inode);
 775                         node->inode = curino;
 776                         node->inode->nlink++;
 777                 }
 778         }
 779
 780         free(node->contents);
 781         node->contents = name;
 782         st->st_size = sb.st_size;
 783         return (0);
 784 }
 785
 786 static int
 787 read_mtree_command(FILE *fp)
 788 {
 789         char cmd[10];
 790         int error;
 791
 792         error = read_word(fp, cmd, sizeof(cmd));
 793         if (error)
 794                 goto out;
 795
 796         error = read_mtree_keywords(fp, &mtree_global);
 797
 798  out:
 799         skip_to(fp, "\n");
 800         (void)getc(fp);
 801         return (error);
 802 }
 803
 804 static int
 805 read_mtree_spec1(FILE *fp, bool def, const char *name)
 806 {
 807         fsnode *last, *node, *parent;
 808         u_int type;
 809         int error;
 810
 811         assert(name[0] != '\0');
 812
 813         /*
 814          * Treat '..' specially, because it only changes our current
 815          * directory. We don't create a node for it. We simply ignore
 816          * any keywords that may appear on the line as well.
 817          * Going up a directory is a little non-obvious. A directory
 818          * node has a corresponding '.' child. The parent of '.' is
 819          * not the '.' node of the parent directory, but the directory
 820          * node within the parent to which the child relates. However,
 821          * going up a directory means we need to find the '.' node to
 822          * which the directoy node is linked.  This we can do via the
 823          * first * pointer, because '.' is always the first entry in a
 824          * directory.
 825          */
 826         if (IS_DOTDOT(name)) {
 827                 /* This deals with NULL pointers as well. */
 828                 if (mtree_current == mtree_root) {
 829                         mtree_warning("ignoring .. in root directory");
 830                         return (0);
 831                 }
 832
 833                 node = mtree_current;
 834
 835                 assert(node != NULL);
 836                 assert(IS_DOT(node->name));
 837                 assert(node->first == node);
 838
 839                 /* Get the corresponding directory node in the parent. */
 840                 node = mtree_current->parent;
 841
 842                 assert(node != NULL);
 843                 assert(!IS_DOT(node->name));
 844
 845                 node = node->first;
 846
 847                 assert(node != NULL);
 848                 assert(IS_DOT(node->name));
 849                 assert(node->first == node);
 850
 851                 mtree_current = node;
 852                 return (0);
 853         }
 854
 855         /*
 856          * If we don't have a current directory and the first specification
 857          * (either implicit or defined) is not '.', then we need to create
 858          * a '.' node first (using a recursive call).
 859          */
 860         if (!IS_DOT(name) && mtree_current == NULL) {
 861                 error = read_mtree_spec1(fp, false, ".");
 862                 if (error)
 863                         return (error);
 864         }
 865
 866         /*
 867          * Lookup the name in the current directory (if we have a current
 868          * directory) to make sure we do not create multiple nodes for the
 869          * same component. For non-definitions, if we find a node with the
 870          * same name, simply change the current directory. For definitions
 871          * more happens.
 872          */
 873         last = NULL;
 874         node = mtree_current;
 875         while (node != NULL) {
 876                 assert(node->first == mtree_current);
 877
 878                 if (strcmp(name, node->name) == 0) {
 879                         if (def == true) {
 880                                 if (!dupsok)
 881                                         mtree_error(
 882                                             "duplicate definition of %s",
 883                                             name);
 884                                 else
 885                                         mtree_warning(
 886                                             "duplicate definition of %s",
 887                                             name);
 888                                 return (0);
 889                         }
 890
 891                         if (node->type != S_IFDIR) {
 892                                 mtree_error("%s is not a directory", name);
 893                                 return (0);
 894                         }
 895
 896                         assert(!IS_DOT(name));
 897
 898                         node = node->child;
 899
 900                         assert(node != NULL);
 901                         assert(IS_DOT(node->name));
 902
 903                         mtree_current = node;
 904                         return (0);
 905                 }
 906
 907                 last = node;
 908                 node = last->next;
 909         }
 910
 911         parent = (mtree_current != NULL) ? mtree_current->parent : NULL;
 912         type = (def == false || IS_DOT(name)) ? S_IFDIR : 0;
 913         node = create_node(name, type, parent, &mtree_global);
 914         if (node == NULL)
 915                 return (ENOMEM);
 916
 917         if (def == true) {
 918                 error = read_mtree_keywords(fp, node);
 919                 if (error) {
 920                         destroy_node(node);
 921                         return (error);
 922                 }
 923         }
 924
 925         node->first = (mtree_current != NULL) ? mtree_current : node;
 926
 927         if (last != NULL)
 928                 last->next = node;
 929
 930         if (node->type != S_IFDIR)
 931                 return (0);
 932
 933         if (!IS_DOT(node->name)) {
 934                 parent = node;
 935                 node = create_node(".", S_IFDIR, parent, parent);
 936                 if (node == NULL) {
 937                         last->next = NULL;
 938                         destroy_node(parent);
 939                         return (ENOMEM);
 940                 }
 941                 parent->child = node;
 942                 node->first = node;
 943         }
 944
 945         assert(node != NULL);
 946         assert(IS_DOT(node->name));
 947         assert(node->first == node);
 948
 949         mtree_current = node;
 950         if (mtree_root == NULL)
 951                 mtree_root = node;
 952
 953         return (0);
 954 }
 955
 956 static int
 957 read_mtree_spec(FILE *fp)
 958 {
 959         char pathspec[PATH_MAX], pathtmp[4*PATH_MAX + 1];
 960         char *cp;
 961         int error;
 962
 963         error = read_word(fp, pathtmp, sizeof(pathtmp));
 964         if (error)
 965                 goto out;
 966         if (strnunvis(pathspec, PATH_MAX, pathtmp) == -1) {
 967                 error = errno;
 968                 goto out;
 969         }
 970         error = 0;
 971
 972         cp = strchr(pathspec, '/');
 973         if (cp != NULL) {
 974                 /* Absolute pathname */
 975                 mtree_current = mtree_root;
 976
 977                 do {
 978                         *cp++ = '\0';
 979
 980                         /* Disallow '..' as a component. */
 981                         if (IS_DOTDOT(pathspec)) {
 982                                 mtree_error("absolute path cannot contain "
 983                                     ".. component");
 984                                 goto out;
 985                         }
 986
 987                         /* Ignore multiple adjacent slashes and '.'. */
 988                         if (pathspec[0] != '\0' && !IS_DOT(pathspec))
 989                                 error = read_mtree_spec1(fp, false, pathspec);
 990                         memmove(pathspec, cp, strlen(cp) + 1);
 991                         cp = strchr(pathspec, '/');
 992                 } while (!error && cp != NULL);
 993
 994                 /* Disallow '.' and '..' as the last component. */
 995                 if (!error && (IS_DOT(pathspec) || IS_DOTDOT(pathspec))) {
 996                         mtree_error("absolute path cannot contain . or .. "
 997                             "components");
 998                         goto out;
 999                 }
1000         }
1001
1002         /* Ignore absolute specfications that end with a slash. */
1003         if (!error && pathspec[0] != '\0')
1004                 error = read_mtree_spec1(fp, true, pathspec);
1005
1006  out:
1007         skip_to(fp, "\n");
1008         (void)getc(fp);
1009         return (error);
1010 }
1011
1012 fsnode *
1013 read_mtree(const char *fname, fsnode *node)
1014 {
1015         struct mtree_fileinfo *fi;
1016         FILE *fp;
1017         int c, error;
1018
1019         /* We do not yet support nesting... */
1020         assert(node == NULL);
1021
1022         if (strcmp(fname, "-") == 0)
1023                 fp = stdin;
1024         else {
1025                 fp = fopen(fname, "r");
1026                 if (fp == NULL)
1027                         err(1, "Can't open `%s'", fname);
1028         }
1029
1030         error = mtree_file_push(fname, fp);
1031         if (error)
1032                 goto out;
1033
1034         memset(&mtree_global, 0, sizeof(mtree_global));
1035         memset(&mtree_global_inode, 0, sizeof(mtree_global_inode));
1036         mtree_global.inode = &mtree_global_inode;
1037         mtree_global_inode.nlink = 1;
1038         mtree_global_inode.st.st_nlink = 1;
1039         mtree_global_inode.st.st_atime = mtree_global_inode.st.st_ctime =
1040             mtree_global_inode.st.st_mtime = time(NULL);
1041         errors = warnings = 0;
1042
1043         setgroupent(1);
1044         setpassent(1);
1045
1046         mtree_root = node;
1047         mtree_current = node;
1048         do {
1049                 /* Start of a new line... */
1050                 fi = SLIST_FIRST(&mtree_fileinfo);
1051                 fi->line++;
1052
1053                 error = skip_over(fp, " \t");
1054                 if (error)
1055                         break;
1056
1057                 c = getc(fp);
1058                 if (c == EOF) {
1059                         error = ferror(fp) ? errno : -1;
1060                         break;
1061                 }
1062
1063                 switch (c) {
1064                 case '\n':              /* empty line */
1065                         error = 0;
1066                         break;
1067                 case '#':               /* comment -- skip to end of line. */
1068                         error = skip_to(fp, "\n");
1069                         if (!error)
1070                                 (void)getc(fp);
1071                         break;
1072                 case '/':               /* special commands */
1073                         error = read_mtree_command(fp);
1074                         break;
1075                 default:                /* specification */
1076                         ungetc(c, fp);
1077                         error = read_mtree_spec(fp);
1078                         break;
1079                 }
1080         } while (!error);
1081
1082         endpwent();
1083         endgrent();
1084
1085         if (error <= 0 && (errors || warnings)) {
1086                 warnx("%u error(s) and %u warning(s) in mtree manifest",
1087                     errors, warnings);
1088                 if (errors)
1089                         exit(1);
1090         }
1091
1092  out:
1093         if (error > 0)
1094                 errc(1, error, "Error reading mtree file");
1095
1096         if (fp != stdin)
1097                 fclose(fp);
1098
1099         if (mtree_root != NULL)
1100                 return (mtree_root);
1101
1102         /* Handle empty specifications. */
1103         node = create_node(".", S_IFDIR, NULL, &mtree_global);
1104         node->first = node;
1105         return (node);
1106 }