libbb/unarchive.c

   1 /*
   2  *  Copyright (C) 2000 by Glenn McGrath
   3  *  Copyright (C) 2001 by Laurence Anderson
   4  *
   5  *  Based on previous work by busybox developers and others.
   6  *
   7  *  This program is free software; you can redistribute it and/or modify
   8  *  it under the terms of the GNU General Public License as published by
   9  *  the Free Software Foundation; either version 2 of the License, or
  10  *  (at your option) any later version.
  11  *
  12  *  This program is distributed in the hope that it will be useful,
  13  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *  GNU Library General Public License for more details.
  16  *
  17  *  You should have received a copy of the GNU General Public License
  18  *  along with this program; if not, write to the Free Software
  19  *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  20  */
  21
  22 #include <stdio.h>
  23 #include <errno.h>
  24 #include <stdlib.h>
  25 #include <string.h>
  26 #include <unistd.h>
  27 #include <utime.h>
  28 #include "libbb.h"
  29
  30 #define CONFIG_FEATURE_TAR_OLDGNU_COMPATABILITY 1
  31 #define CONFIG_FEATURE_TAR_GNU_EXTENSIONS
  32
  33 #ifdef CONFIG_FEATURE_TAR_GNU_EXTENSIONS
  34 static char *longname = NULL;
  35 static char *linkname = NULL;
  36 #endif
  37
  38 extern void seek_sub_file(FILE *src_stream, const int count);
  39 extern char *extract_archive(FILE *src_stream, FILE *out_stream, const file_header_t *file_entry,
  40                               const int function, const char *prefix);
  41 extern ssize_t seek_by_read(FILE* fd, size_t len);
  42
  43
  44 #ifdef L_archive_offset
  45 off_t archive_offset;
  46 #else
  47 extern off_t archive_offset;
  48 #endif
  49
  50 #ifdef L_seek_sub_file
  51 #define SEEK_BUF 4096
  52 ssize_t seek_by_read(FILE* fd, size_t len)
  53 {
  54         ssize_t cc, total = 0;
  55         char buf[SEEK_BUF];
  56
  57         while (len) {
  58                 cc = fread(buf, sizeof(buf[0]),
  59                                 len > SEEK_BUF ? SEEK_BUF : len,
  60                                 fd);
  61
  62                 total += cc;
  63                 len -= cc;
  64
  65                 if(feof(fd) || ferror(fd))
  66                         break;
  67         }
  68         return total;
  69 }
  70
  71 void seek_sub_file(FILE *src_stream, const int count)
  72 {
  73         /* Try to fseek as faster */
  74         archive_offset += count;
  75         seek_by_read(src_stream, count);
  76         return;
  77 }
  78 #endif
  79
  80
  81
  82 #ifdef L_extract_archive
  83 /* Extract the data postioned at src_stream to either filesystem, stdout or
  84  * buffer depending on the value of 'function' which is defined in libbb.h
  85  *
  86  * prefix doesnt have to be just a directory, it may prefix the filename as well.
  87  *
  88  * e.g. '/var/lib/dpkg/info/dpkg.' will extract all files to the base bath
  89  * '/var/lib/dpkg/info/' and all files/dirs created in that dir will have
  90  * 'dpkg.' as their prefix
  91  *
  92  * For this reason if prefix does point to a dir then it must end with a
  93  * trailing '/' or else the last dir will be assumed to be the file prefix
  94  */
  95 char *extract_archive(FILE *src_stream, FILE *out_stream, const file_header_t *file_entry,
  96  const int function, const char *prefix)
  97 {
  98         FILE *dst_stream = NULL;
  99         char *full_name = NULL;
 100         char *full_link_name = NULL;
 101         char *buffer = NULL;
 102         struct utimbuf t;
 103
 104
 105         /* prefix doesnt have to be a proper path it may prepend
 106          * the filename as well */
 107         if (prefix != NULL) {
 108                 /* strip leading '/' in filename to extract as prefix may not be dir */
 109                 /* Cant use concat_path_file here as prefix might not be a directory */
 110                 char *path = file_entry->name;
 111                 if (strncmp("./", path, 2) == 0) {
 112                         path += 2;
 113                         if (strlen(path) == 0) {
 114                                 return(NULL);
 115                         }
 116                 }
 117                 full_name = xmalloc(strlen(prefix) + strlen(path) + 1);
 118                 strcpy(full_name, prefix);
 119                 strcat(full_name, path);
 120                 if ( file_entry->link_name ){
 121                    full_link_name = xmalloc(strlen(prefix) + strlen(file_entry->link_name) + 1);
 122                    strcpy(full_link_name, prefix);
 123                    strcat(full_link_name, file_entry->link_name);
 124                 }
 125         } else {
 126                 full_name = strdup(file_entry->name);
 127                 if ( file_entry->link_name )
 128                    full_link_name = strdup(file_entry->link_name);
 129         }
 130
 131
 132         if (function & extract_to_stdout) {
 133                 if (S_ISREG(file_entry->mode)) {
 134                         copy_file_chunk(src_stream, out_stream, file_entry->size);
 135                         archive_offset += file_entry->size;
 136                 }
 137         }
 138         else if (function & extract_one_to_buffer) {
 139                 if (S_ISREG(file_entry->mode)) {
 140                         buffer = (char *) xmalloc(file_entry->size + 1);
 141                         fread(buffer, 1, file_entry->size, src_stream);
 142                         buffer[file_entry->size] = '\0';
 143                         archive_offset += file_entry->size;
 144                         return(buffer);
 145                 }
 146         }
 147         else if (function & extract_all_to_fs) {
 148                 struct stat oldfile;
 149                 int stat_res;
 150                 stat_res = lstat (full_name, &oldfile);
 151                 if (stat_res == 0) { /* The file already exists */
 152                         if ((function & extract_unconditional) || (oldfile.st_mtime < file_entry->mtime)) {
 153                                 if (!S_ISDIR(oldfile.st_mode)) {
 154                                         unlink(full_name); /* Directories might not be empty etc */
 155                                 }
 156                         } else {
 157                                 if ((function & extract_quiet) != extract_quiet) {
 158                                         error_msg("%s not created: newer or same age file exists", file_entry->name);
 159                                 }
 160                                 seek_sub_file(src_stream, file_entry->size);
 161                                 return (NULL);
 162                         }
 163                 }
 164                 if (function & extract_create_leading_dirs) { /* Create leading directories with default umask */
 165                         char *buf, *parent;
 166                         buf = xstrdup(full_name);
 167                         parent = dirname(buf);
 168                         if (make_directory (parent, -1, FILEUTILS_RECUR) != 0) {
 169                                 if ((function & extract_quiet) != extract_quiet) {
 170                                         error_msg("couldn't create leading directories");
 171                                 }
 172                         }
 173                         free (buf);
 174                 }
 175                 switch(file_entry->mode & S_IFMT) {
 176                         case S_IFREG:
 177                                 if (file_entry->link_name) { /* Found a cpio hard link */
 178                                         if (link(full_link_name, full_name) != 0) {
 179                                                 if ((function & extract_quiet) != extract_quiet) {
 180                                                         perror_msg("Cannot link from %s to '%s'",
 181                                                                 file_entry->name, file_entry->link_name);
 182                                                 }
 183                                         }
 184                                 } else {
 185                                         if ((dst_stream = wfopen(full_name, "w")) == NULL) {
 186                                                 seek_sub_file(src_stream, file_entry->size);
 187                                                 return NULL;
 188                                         }
 189                                         archive_offset += file_entry->size;
 190                                         copy_file_chunk(src_stream, dst_stream, file_entry->size);
 191                                         fclose(dst_stream);
 192                                 }
 193                                 break;
 194                         case S_IFDIR:
 195                                 if (stat_res != 0) {
 196                                         if (mkdir(full_name, file_entry->mode) < 0) {
 197                                                 if ((function & extract_quiet) != extract_quiet) {
 198                                                         perror_msg("extract_archive: %s", full_name);
 199                                                 }
 200                                         }
 201                                 }
 202                                 break;
 203                         case S_IFLNK:
 204                                 if (symlink(file_entry->link_name, full_name) < 0) {
 205                                         if ((function & extract_quiet) != extract_quiet) {
 206                                                 perror_msg("Cannot create symlink from %s to '%s'", file_entry->name, file_entry->link_name);
 207                                         }
 208                                         return NULL;
 209                                 }
 210                                 break;
 211                         case S_IFSOCK:
 212                         case S_IFBLK:
 213                         case S_IFCHR:
 214                         case S_IFIFO:
 215                                 if (mknod(full_name, file_entry->mode, file_entry->device) == -1) {
 216                                         if ((function & extract_quiet) != extract_quiet) {
 217                                                 perror_msg("Cannot create node %s", file_entry->name);
 218                                         }
 219                                         return NULL;
 220                                 }
 221                                 break;
 222                          default:
 223                             perror_msg("Don't know how to handle %s", full_name);
 224
 225                 }
 226
 227                 /* Changing a symlink's properties normally changes the properties of the
 228                  * file pointed to, so dont try and change the date or mode, lchown does
 229                  * does the right thing, but isnt available in older versions of libc */
 230                 if (S_ISLNK(file_entry->mode)) {
 231 #if (__GLIBC__ > 2) && (__GLIBC_MINOR__ > 1)
 232                         lchown(full_name, file_entry->uid, file_entry->gid);
 233 #endif
 234                 } else {
 235                         if (function & extract_preserve_date) {
 236                                 t.actime = file_entry->mtime;
 237                                 t.modtime = file_entry->mtime;
 238                                 utime(full_name, &t);
 239                         }
 240                         chown(full_name, file_entry->uid, file_entry->gid);
 241                         chmod(full_name, file_entry->mode);
 242                 }
 243         } else {
 244                 /* If we arent extracting data we have to skip it,
 245                  * if data size is 0 then then just do it anyway
 246                  * (saves testing for it) */
 247                 seek_sub_file(src_stream, file_entry->size);
 248         }
 249
 250         /* extract_list and extract_verbose_list can be used in conjunction
 251          * with one of the above four extraction functions, so do this seperately */
 252         if (function & extract_verbose_list) {
 253                 fprintf(out_stream, "%s %d/%d %8d %s ", mode_string(file_entry->mode),
 254                         file_entry->uid, file_entry->gid,
 255                         (int) file_entry->size, time_string(file_entry->mtime));
 256         }
 257         if ((function & extract_list) || (function & extract_verbose_list)){
 258                 /* fputs doesnt add a trailing \n, so use fprintf */
 259                 fprintf(out_stream, "%s\n", file_entry->name);
 260         }
 261
 262         free(full_name);
 263         if ( full_link_name )
 264             free(full_link_name);
 265
 266         return(NULL); /* Maybe we should say if failed */
 267 }
 268 #endif
 269
 270 #ifdef L_unarchive
 271 char *unarchive(FILE *src_stream, FILE *out_stream,
 272                 file_header_t *(*get_headers)(FILE *),
 273                 void (*free_headers)(file_header_t *),
 274                 const int extract_function, const char *prefix, char **extract_names)
 275 {
 276         file_header_t *file_entry;
 277         int extract_flag;
 278         int i;
 279         char *buffer = NULL;
 280
 281         archive_offset = 0;
 282         while ((file_entry = get_headers(src_stream)) != NULL) {
 283                 extract_flag = TRUE;
 284                 /* fprintf(stderr, __FUNCTION__ " getting headers\n"); */
 285                 if (extract_names != NULL) {
 286                         int found_flag = FALSE;
 287                         for(i = 0; extract_names[i] != 0; i++) {
 288                                 if (strcmp(extract_names[i], file_entry->name) == 0) {
 289                                         found_flag = TRUE;
 290                                         break;
 291                                 }
 292                         }
 293                         if (extract_function & extract_exclude_list) {
 294                                 if (found_flag == TRUE) {
 295                                         extract_flag = FALSE;
 296                                 }
 297                         } else {
 298                                 /* If its not found in the include list dont extract it */
 299                                 if (found_flag == FALSE) {
 300                                         extract_flag = FALSE;
 301                                 }
 302                         }
 303
 304                 }
 305
 306                 if (extract_flag == TRUE) {
 307                         /* fprintf(stderr, __FUNCTION__ " extract?\n"); */
 308                         buffer = extract_archive(src_stream, out_stream, file_entry, extract_function, prefix);
 309                         /* fprintf(stderr, __FUNCTION__ " extracted\n"); */
 310                 } else {
 311                         /* seek past the data entry */
 312                         seek_sub_file(src_stream, file_entry->size);
 313                 }
 314                 free_headers(file_entry);
 315         }
 316         /*fprintf(stderr, __FUNCTION__ " goin home\n");*/
 317
 318         return(buffer);
 319 }
 320 #endif
 321
 322 #ifdef L_get_header_ar
 323 file_header_t *get_header_ar(FILE *src_stream)
 324 {
 325         file_header_t *typed;
 326         union {
 327                 char raw[60];
 328                 struct {
 329                         char name[16];
 330                         char date[12];
 331                         char uid[6];
 332                         char gid[6];
 333                         char mode[8];
 334                         char size[10];
 335                         char magic[2];
 336                 } formated;
 337         } ar;
 338         static char *ar_long_names;
 339
 340         if (fread(ar.raw, 1, 60, src_stream) != 60) {
 341                 return(NULL);
 342         }
 343         archive_offset += 60;
 344         /* align the headers based on the header magic */
 345         if ((ar.formated.magic[0] != '`') || (ar.formated.magic[1] != '\n')) {
 346                 /* some version of ar, have an extra '\n' after each data entry,
 347                  * this puts the next header out by 1 */
 348                 if (ar.formated.magic[1] != '`') {
 349                         error_msg("Invalid magic");
 350                         return(NULL);
 351                 }
 352                 /* read the next char out of what would be the data section,
 353                  * if its a '\n' then it is a valid header offset by 1*/
 354                 archive_offset++;
 355                 if (fgetc(src_stream) != '\n') {
 356                         error_msg("Invalid magic");
 357                         return(NULL);
 358                 }
 359                 /* fix up the header, we started reading 1 byte too early */
 360                 /* raw_header[60] wont be '\n' as it should, but it doesnt matter */
 361                 memmove(ar.raw, &ar.raw[1], 59);
 362         }
 363
 364         typed = (file_header_t *) xcalloc(1, sizeof(file_header_t));
 365
 366         typed->size = (size_t) atoi(ar.formated.size);
 367         /* long filenames have '/' as the first character */
 368         if (ar.formated.name[0] == '/') {
 369                 if (ar.formated.name[1] == '/') {
 370                         /* If the second char is a '/' then this entries data section
 371                          * stores long filename for multiple entries, they are stored
 372                          * in static variable long_names for use in future entries */
 373                         ar_long_names = (char *) xrealloc(ar_long_names, typed->size);
 374                         fread(ar_long_names, 1, typed->size, src_stream);
 375                         archive_offset += typed->size;
 376                         /* This ar entries data section only contained filenames for other records
 377                          * they are stored in the static ar_long_names for future reference */
 378                         return (get_header_ar(src_stream)); /* Return next header */
 379                 } else if (ar.formated.name[1] == ' ') {
 380                         /* This is the index of symbols in the file for compilers */
 381                         seek_sub_file(src_stream, typed->size);
 382                         return (get_header_ar(src_stream)); /* Return next header */
 383                 } else {
 384                         /* The number after the '/' indicates the offset in the ar data section
 385                         (saved in variable long_name) that conatains the real filename */
 386                         if (!ar_long_names) {
 387                                 error_msg("Cannot resolve long file name");
 388                                 return (NULL);
 389                         }
 390                         typed->name = xstrdup(ar_long_names + atoi(&ar.formated.name[1]));
 391                 }
 392         } else {
 393                 /* short filenames */
 394                 typed->name = xcalloc(1, 16);
 395                 strncpy(typed->name, ar.formated.name, 16);
 396         }
 397         typed->name[strcspn(typed->name, " /")]='\0';
 398
 399         /* convert the rest of the now valid char header to its typed struct */
 400         parse_mode(ar.formated.mode, &typed->mode);
 401         typed->mtime = atoi(ar.formated.date);
 402         typed->uid = atoi(ar.formated.uid);
 403         typed->gid = atoi(ar.formated.gid);
 404
 405         return(typed);
 406 }
 407
 408 void free_header_ar(file_header_t *ar_entry)
 409 {
 410     if (ar_entry == NULL) {
 411         return;
 412     }
 413
 414     free(ar_entry->name);
 415     free(ar_entry->link_name);
 416
 417     free(ar_entry);
 418 }
 419 #endif
 420
 421 #ifdef L_get_header_cpio
 422 struct hardlinks {
 423         file_header_t *entry;
 424         int inode;
 425         struct hardlinks *next;
 426 };
 427
 428 file_header_t *get_header_cpio(FILE *src_stream)
 429 {
 430         file_header_t *cpio_entry = NULL;
 431         char cpio_header[110];
 432         int namesize;
 433         char dummy[16];
 434         int major, minor, nlink, inode;
 435         static struct hardlinks *saved_hardlinks = NULL;
 436         static int pending_hardlinks = 0;
 437
 438
 439         if (pending_hardlinks) { /* Deal with any pending hardlinks */
 440                 struct hardlinks *tmp = saved_hardlinks, *oldtmp = NULL;
 441                 while (tmp) {
 442                         if (tmp->entry->link_name) { /* Found a hardlink ready to be extracted */
 443                                 cpio_entry = tmp->entry;
 444                                 if (oldtmp) oldtmp->next = tmp->next; /* Remove item from linked list */
 445                                 else saved_hardlinks = tmp->next;
 446                                 free(tmp);
 447                                 return (cpio_entry);
 448                         }
 449                         oldtmp = tmp;
 450                         tmp = tmp->next;
 451                 }
 452                 pending_hardlinks = 0; /* No more pending hardlinks, read next file entry */
 453         }
 454
 455         /* There can be padding before archive header */
 456         seek_sub_file(src_stream, (4 - (archive_offset % 4)) % 4);
 457         if (fread(cpio_header, 1, 110, src_stream) == 110) {
 458                 archive_offset += 110;
 459                 if (strncmp(cpio_header, "07070", 5) != 0) {
 460                         error_msg("Unsupported format or invalid magic");
 461                         return(NULL);
 462                 }
 463                 switch (cpio_header[5]) {
 464                         case '2': /* "crc" header format */
 465                                 /* Doesnt do the crc check yet */
 466                         case '1': /* "newc" header format */
 467                                 cpio_entry = (file_header_t *) xcalloc(1, sizeof(file_header_t));
 468                                 sscanf(cpio_header, "%6c%8x%8x%8x%8x%8x%8lx%8lx%16c%8x%8x%8x%8c",
 469                                         dummy, &inode, (unsigned int*)&cpio_entry->mode,
 470                                         (unsigned int*)&cpio_entry->uid, (unsigned int*)&cpio_entry->gid,
 471                                         &nlink, &cpio_entry->mtime, (unsigned long*)&cpio_entry->size,
 472                                         dummy, &major, &minor, &namesize, dummy);
 473
 474                                 cpio_entry->name = (char *) xcalloc(1, namesize);
 475                                 fread(cpio_entry->name, 1, namesize, src_stream); /* Read in filename */
 476                                 archive_offset += namesize;
 477                                 /* Skip padding before file contents */
 478                                 seek_sub_file(src_stream, (4 - (archive_offset % 4)) % 4);
 479                                 if (strcmp(cpio_entry->name, "TRAILER!!!") == 0) {
 480                                         printf("%d blocks\n", (int) (archive_offset % 512 ? (archive_offset / 512) + 1 : archive_offset / 512)); /* Always round up */
 481                                         if (saved_hardlinks) { /* Bummer - we still have unresolved hardlinks */
 482                                                 struct hardlinks *tmp = saved_hardlinks, *oldtmp = NULL;
 483                                                 while (tmp) {
 484                                                         error_msg("%s not created: cannot resolve hardlink", tmp->entry->name);
 485                                                         oldtmp = tmp;
 486                                                         tmp = tmp->next;
 487                                                         free (oldtmp->entry->name);
 488                                                         free (oldtmp->entry);
 489                                                         free (oldtmp);
 490                                                 }
 491                                                 saved_hardlinks = NULL;
 492                                                 pending_hardlinks = 0;
 493                                         }
 494                                         return(NULL);
 495                                 }
 496
 497                                 if (S_ISLNK(cpio_entry->mode)) {
 498                                         cpio_entry->link_name = (char *) xcalloc(1, cpio_entry->size + 1);
 499                                         fread(cpio_entry->link_name, 1, cpio_entry->size, src_stream);
 500                                         archive_offset += cpio_entry->size;
 501                                         cpio_entry->size = 0; /* Stop possiable seeks in future */
 502                                 }
 503                                 if (nlink > 1 && !S_ISDIR(cpio_entry->mode)) {
 504                                         if (cpio_entry->size == 0) { /* Put file on a linked list for later */
 505                                                 struct hardlinks *new = xmalloc(sizeof(struct hardlinks));
 506                                                 new->next = saved_hardlinks;
 507                                                 new->inode = inode;
 508                                                 new->entry = cpio_entry;
 509                                                 saved_hardlinks = new;
 510                                         return(get_header_cpio(src_stream)); /* Recurse to next file */
 511                                         } else { /* Found the file with data in */
 512                                                 struct hardlinks *tmp = saved_hardlinks;
 513                                                 pending_hardlinks = 1;
 514                                                 while (tmp) {
 515                                                         if (tmp->inode == inode) {
 516                                                                 tmp->entry->link_name = xstrdup(cpio_entry->name);
 517                                                                 nlink--;
 518                                                         }
 519                                                         tmp = tmp->next;
 520                                                 }
 521                                                 if (nlink > 1) error_msg("error resolving hardlink: did you create the archive with GNU cpio 2.0-2.2?");
 522                                         }
 523                                 }
 524                                 cpio_entry->device = (major << 8) | minor;
 525                                 break;
 526                         default:
 527                                 error_msg("Unsupported format");
 528                                 return(NULL);
 529                 }
 530                 if (ferror(src_stream) || feof(src_stream)) {
 531                         perror_msg("Stream error");
 532                         return(NULL);
 533                 }
 534         }
 535         return(cpio_entry);
 536 }
 537 #endif
 538
 539 #ifdef L_get_header_tar
 540 file_header_t *get_header_tar(FILE *tar_stream)
 541 {
 542
 543         union {
 544                 unsigned char raw[512];
 545                 struct {
 546                         char name[100];         /*   0-99 */
 547                         char mode[8];           /* 100-107 */
 548                         char uid[8];            /* 108-115 */
 549                         char gid[8];            /* 116-123 */
 550                         char size[12];          /* 124-135 */
 551                         char mtime[12];         /* 136-147 */
 552                         char chksum[8];         /* 148-155 */
 553                         char typeflag;          /* 156-156 */
 554                         char linkname[100];     /* 157-256 */
 555                         char magic[6];          /* 257-262 */
 556                         char version[2];        /* 263-264 */
 557                         char uname[32];         /* 265-296 */
 558                         char gname[32];         /* 297-328 */
 559                         char devmajor[8];       /* 329-336 */
 560                         char devminor[8];       /* 337-344 */
 561                         char prefix[155];       /* 345-499 */
 562                         char padding[12];       /* 500-512 */
 563                 } formated;
 564         } tar;
 565         file_header_t *tar_entry = NULL;
 566         long i;
 567         long sum = 0;
 568
 569         if (archive_offset % 512 != 0) {
 570                 seek_sub_file(tar_stream, 512 - (archive_offset % 512));
 571         }
 572
 573         if (fread(tar.raw, 1, 512, tar_stream) != 512) {
 574                 /* Unfortunatly its common for tar files to have all sorts of
 575                  * trailing garbage, fail silently */
 576 //              error_msg("Couldnt read header");
 577                 return(NULL);
 578         }
 579         archive_offset += 512;
 580
 581         /* Check header has valid magic, unfortunately some tar files
 582          * have empty (0'ed) tar entries at the end, which will
 583          * cause this to fail, so fail silently for now
 584          */
 585         if (strncmp(tar.formated.magic, "ustar", 5) != 0) {
 586 #ifdef CONFIG_FEATURE_TAR_OLDGNU_COMPATABILITY
 587                 if (strncmp(tar.formated.magic, "\0\0\0\0\0", 5) != 0)
 588 #endif
 589                 return(NULL);
 590         }
 591
 592         /* Do checksum on headers */
 593         for (i =  0; i < 148 ; i++) {
 594                 sum += tar.raw[i];
 595         }
 596         sum += ' ' * 8;
 597         for (i =  156; i < 512 ; i++) {
 598                 sum += tar.raw[i];
 599         }
 600         if (sum != strtol(tar.formated.chksum, NULL, 8)) {
 601                 if ( strtol(tar.formated.chksum,NULL,8) != 0 )
 602                         error_msg("Invalid tar header checksum");
 603                 return(NULL);
 604         }
 605
 606         /* convert to type'ed variables */
 607         tar_entry = xcalloc(1, sizeof(file_header_t));
 608
 609 #ifdef CONFIG_FEATURE_TAR_GNU_EXTENSIONS
 610         if (longname) {
 611                 tar_entry->name = longname;
 612                 longname = NULL;
 613         }
 614         else if (linkname) {
 615                 tar_entry->name = linkname;
 616                 linkname = NULL;
 617         } else
 618 #endif
 619         {
 620                 tar_entry->name = xstrndup(tar.formated.name, 100);
 621
 622                 if (tar.formated.prefix[0]) {
 623                         char *temp = tar_entry->name;
 624                         char *prefixTemp = xstrndup(tar.formated.prefix, 155);
 625                         tar_entry->name = concat_path_file(prefixTemp, temp);
 626                         free(temp);
 627                         free(prefixTemp);
 628                 }
 629         }
 630
 631         // tar_entry->name = xstrdup(tar.formated.name);
 632
 633 /*
 634         parse_mode(tar.formated.mode, &tar_entry->mode);
 635 */
 636         tar_entry->mode = 07777 & strtol(tar.formated.mode, NULL, 8);
 637
 638         tar_entry->uid   = strtol(tar.formated.uid, NULL, 8);
 639         tar_entry->gid   = strtol(tar.formated.gid, NULL, 8);
 640         tar_entry->size  = strtol(tar.formated.size, NULL, 8);
 641         tar_entry->mtime = strtol(tar.formated.mtime, NULL, 8);
 642         tar_entry->link_name  = *tar.formated.linkname != '\0' ? xstrndup(tar.formated.linkname, 100) : NULL;
 643         tar_entry->device = (strtol(tar.formated.devmajor, NULL, 8) << 8) +
 644                 strtol(tar.formated.devminor, NULL, 8);
 645
 646         /* Fix mode, used by the old format */
 647         switch (tar.formated.typeflag) {
 648         /* hard links are detected as regular files with 0 size and a link name */
 649         case '1':
 650                 tar_entry->mode |= S_IFREG ;
 651                 break;
 652         case 0:
 653         case '0':
 654
 655 # ifdef CONFIG_FEATURE_TAR_OLDGNU_COMPATABILITY
 656                 if (last_char_is(tar_entry->name, '/')) {
 657                         tar_entry->mode |= S_IFDIR;
 658                 } else
 659 # endif
 660                         tar_entry->mode |= S_IFREG;
 661                 break;
 662         case '2':
 663                 tar_entry->mode |= S_IFLNK;
 664                 break;
 665         case '3':
 666                 tar_entry->mode |= S_IFCHR;
 667                 break;
 668         case '4':
 669                 tar_entry->mode |= S_IFBLK;
 670                 break;
 671         case '5':
 672                 tar_entry->mode |= S_IFDIR;
 673                 break;
 674         case '6':
 675                 tar_entry->mode |= S_IFIFO;
 676                 break;
 677 # ifdef CONFIG_FEATURE_TAR_GNU_EXTENSIONS
 678         case 'L': {
 679                         longname = xmalloc(tar_entry->size + 1);
 680                         if(fread(longname, tar_entry->size, 1, tar_stream) != 1)
 681                                 return NULL;
 682                         longname[tar_entry->size] = '\0';
 683                         archive_offset += tar_entry->size;
 684
 685                         return(get_header_tar(tar_stream));
 686                 }
 687         case 'K': {
 688                         linkname = xmalloc(tar_entry->size + 1);
 689                         if(fread(linkname, tar_entry->size, 1, tar_stream) != 1)
 690                                 return NULL;
 691                         linkname[tar_entry->size] = '\0';
 692                         archive_offset += tar_entry->size;
 693
 694                         tar_entry->name = linkname;
 695                         return(get_header_tar(tar_stream));
 696                 }
 697         case 'D':
 698         case 'M':
 699         case 'N':
 700         case 'S':
 701         case 'V':
 702                 perror_msg("Ignoring GNU extension type %c", tar.formated.typeflag);
 703 # endif
 704         default:
 705                 perror_msg("Unknown typeflag: 0x%x", tar.formated.typeflag);
 706                 break;
 707
 708         }
 709
 710         return(tar_entry);
 711 }
 712
 713 void free_header_tar(file_header_t *tar_entry)
 714 {
 715     if (tar_entry == NULL) {
 716         return;
 717     }
 718
 719     free(tar_entry->name);
 720     free(tar_entry->link_name);
 721
 722     free(tar_entry);
 723 }
 724
 725 #endif
 726
 727 #ifdef L_deb_extract
 728 char *deb_extract(const char *package_filename, FILE *out_stream,
 729                   const int extract_function, const char *prefix, const char *filename)
 730 {
 731         FILE *deb_stream;
 732         FILE *uncompressed_stream = NULL;
 733         file_header_t *ar_header = NULL;
 734         char **file_list = NULL;
 735         char *output_buffer = NULL;
 736         char *ared_file = NULL;
 737         char ar_magic[8];
 738         int gunzip_pid = 0;
 739
 740         if (filename != NULL) {
 741                 file_list = xmalloc(sizeof(char *) * 2);
 742                 file_list[0] = xstrdup(filename);
 743                 file_list[1] = NULL;
 744         }
 745
 746         if (extract_function & extract_control_tar_gz) {
 747                 ared_file = xstrdup("control.tar.gz");
 748         }
 749         else if (extract_function & extract_data_tar_gz) {
 750                 ared_file = xstrdup("data.tar.gz");
 751         } else {
 752                 fprintf(stderr, "no file specified to extract -- extract_function=%x\n", extract_function);
 753                 return NULL;
 754         }
 755
 756         /* open the debian package to be worked on */
 757         deb_stream = wfopen(package_filename, "r");
 758         if (deb_stream == NULL) {
 759                 return(NULL);
 760         }
 761         /* set the buffer size */
 762         setvbuf(deb_stream, NULL, _IOFBF, 0x8000);
 763
 764         /* check ar magic */
 765         fread(ar_magic, 1, 8, deb_stream);
 766         /*fprintf(stderr, "deb_extract ar_magic=%08x\n", *(long *)ar_magic);*/
 767         if (strncmp(ar_magic,"!<arch>",7) == 0) {
 768                 archive_offset = 8;
 769
 770                 while ((ar_header = get_header_ar(deb_stream)) != NULL) {
 771                         if (strcmp(ared_file, ar_header->name) == 0) {
 772                                 /* open a stream of decompressed data */
 773                                 uncompressed_stream = gz_open(deb_stream, &gunzip_pid);
 774                                 if (uncompressed_stream == NULL) {
 775                                         return(NULL);
 776                                 }
 777
 778                                 archive_offset = 0;
 779                                 output_buffer = unarchive(uncompressed_stream, out_stream, get_header_tar, free_header_tar, extract_function, prefix, file_list);
 780                         }
 781                         seek_sub_file(deb_stream, ar_header->size);
 782                         free (ar_header->name);
 783                         free (ar_header);
 784                 }
 785                 gz_close(gunzip_pid);
 786                 fclose(deb_stream);
 787                 fclose(uncompressed_stream);
 788                 free(ared_file);
 789                 return(output_buffer);
 790         } else if (strncmp(ar_magic, "\037\213", 2) == 0) {
 791                 /* it's a gz file, let's assume it's an opkg */
 792                 int unzipped_opkg_pid;
 793                 FILE *unzipped_opkg_stream;
 794                 file_header_t *tar_header;
 795                 archive_offset = 0;
 796                 fseek(deb_stream, 0, SEEK_SET);
 797                 unzipped_opkg_stream = gz_open(deb_stream, &unzipped_opkg_pid);
 798                 if (unzipped_opkg_stream == NULL) {
 799                         return(NULL);
 800                 }
 801
 802                 /*fprintf(stderr, __FUNCTION__ ": processing opkg %s -- ared_file=%s\n", package_filename, ared_file);*/
 803                 /* walk through outer tar file to find ared_file */
 804                 while ((tar_header = get_header_tar(unzipped_opkg_stream)) != NULL) {
 805                         int name_offset = 0;
 806                         if (strncmp(tar_header->name, "./", 2) == 0)
 807                                 name_offset = 2;
 808                         if (strcmp(ared_file, tar_header->name+name_offset) == 0) {
 809                                 /* open a stream of decompressed data */
 810                                 uncompressed_stream = gz_open(unzipped_opkg_stream, &gunzip_pid);
 811                                 if (uncompressed_stream == NULL) {
 812                                         return(NULL);
 813                                 }
 814                                 archive_offset = 0;
 815                                 /*fprintf(stderr, __FUNCTION__ ":%d: here -- found file\n", __LINE__);*/
 816                                 output_buffer = unarchive(uncompressed_stream,
 817                                                           out_stream,
 818                                                           get_header_tar,
 819                                                           free_header_tar,
 820                                                           extract_function,
 821                                                           prefix,
 822                                                           file_list);
 823                                 /*fprintf(stderr, __FUNCTION__ ":%d: unarchive complete\n", __LINE__);*/
 824                                 free_header_tar(tar_header);
 825                                 gz_close(gunzip_pid);
 826                                 fclose(uncompressed_stream);
 827                                 break;
 828                         }
 829                         seek_sub_file(unzipped_opkg_stream, tar_header->size);
 830                         free_header_tar(tar_header);
 831                 }
 832                 gz_close(unzipped_opkg_pid);
 833                 fclose(unzipped_opkg_stream);
 834                 fclose(deb_stream);
 835                 free(ared_file);
 836                 /*fprintf(stderr, __FUNCTION__ ":%d: done\n", __LINE__);*/
 837                 return output_buffer;
 838         } else {
 839                 error_msg_and_die("invalid magic");
 840         }
 841
 842 }
 843 #endif