tar.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * Mini tar implementation for busybox
   4  *
   5  * Note, that as of BusyBox-0.43, tar has been completely rewritten from the
   6  * ground up.  It still has remnents of the old code lying about, but it is
   7  * very different now (i.e. cleaner, less global variables, etc)
   8  *
   9  * Copyright (C) 2000 by Lineo, inc.
  10  * Written by Erik Andersen <andersen@lineo.com>, <andersee@debian.org>
  11  *
  12  * Based in part in the tar implementation in sash
  13  *  Copyright (c) 1999 by David I. Bell
  14  *  Permission is granted to use, distribute, or modify this source,
  15  *  provided that this copyright notice remains intact.
  16  *  Permission to distribute sash derived code under the GPL has been granted.
  17  *
  18  * Based in part on the tar implementation from busybox-0.28
  19  *  Copyright (C) 1995 Bruce Perens
  20  *  This is free software under the GNU General Public License.
  21  *
  22  * This program is free software; you can redistribute it and/or modify
  23  * it under the terms of the GNU General Public License as published by
  24  * the Free Software Foundation; either version 2 of the License, or
  25  * (at your option) any later version.
  26  *
  27  * This program is distributed in the hope that it will be useful,
  28  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  29  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  30  * General Public License for more details.
  31  *
  32  * You should have received a copy of the GNU General Public License
  33  * along with this program; if not, write to the Free Software
  34  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  35  *
  36  */
  37
  38
  39 #include "busybox.h"
  40 #define BB_DECLARE_EXTERN
  41 #define bb_need_io_error
  42 #define bb_need_name_longer_than_foo
  43 #include "messages.c"
  44 #include <stdio.h>
  45 #include <dirent.h>
  46 #include <errno.h>
  47 #include <fcntl.h>
  48 #include <signal.h>
  49 #include <time.h>
  50 #include <utime.h>
  51 #include <sys/types.h>
  52 #include <sys/sysmacros.h>
  53 #include <getopt.h>
  54
  55 /* Tar file constants  */
  56 #ifndef MAJOR
  57 #define MAJOR(dev) (((dev)>>8)&0xff)
  58 #define MINOR(dev) ((dev)&0xff)
  59 #endif
  60
  61 #define NAME_SIZE       100
  62
  63 /* POSIX tar Header Block, from POSIX 1003.1-1990  */
  64 struct TarHeader
  65 {
  66                                 /* byte offset */
  67         char name[NAME_SIZE];         /*   0-99 */
  68         char mode[8];                 /* 100-107 */
  69         char uid[8];                  /* 108-115 */
  70         char gid[8];                  /* 116-123 */
  71         char size[12];                /* 124-135 */
  72         char mtime[12];               /* 136-147 */
  73         char chksum[8];               /* 148-155 */
  74         char typeflag;                /* 156-156 */
  75         char linkname[NAME_SIZE];     /* 157-256 */
  76         char magic[6];                /* 257-262 */
  77         char version[2];              /* 263-264 */
  78         char uname[32];               /* 265-296 */
  79         char gname[32];               /* 297-328 */
  80         char devmajor[8];             /* 329-336 */
  81         char devminor[8];             /* 337-344 */
  82         char prefix[155];             /* 345-499 */
  83         char padding[12];             /* 500-512 (pad to exactly the TAR_BLOCK_SIZE) */
  84 };
  85 typedef struct TarHeader TarHeader;
  86
  87
  88 /* A few useful constants */
  89 #define TAR_MAGIC          "ustar"        /* ustar and a null */
  90 #define TAR_VERSION        "  "           /* Be compatable with GNU tar format */
  91 #define TAR_MAGIC_LEN       6
  92 #define TAR_VERSION_LEN     2
  93 #define TAR_BLOCK_SIZE      512
  94
  95 /* A nice enum with all the possible tar file content types */
  96 enum TarFileType
  97 {
  98         REGTYPE  = '0',            /* regular file */
  99         REGTYPE0 = '\0',           /* regular file (ancient bug compat)*/
 100         LNKTYPE  = '1',            /* hard link */
 101         SYMTYPE  = '2',            /* symbolic link */
 102         CHRTYPE  = '3',            /* character special */
 103         BLKTYPE  = '4',            /* block special */
 104         DIRTYPE  = '5',            /* directory */
 105         FIFOTYPE = '6',            /* FIFO special */
 106         CONTTYPE = '7',            /* reserved */
 107         GNULONGLINK = 'K',         /* GNU long (>100 chars) link name */
 108         GNULONGNAME = 'L',         /* GNU long (>100 chars) file name */
 109 };
 110 typedef enum TarFileType TarFileType;
 111
 112 /* This struct ignores magic, non-numeric user name,
 113  * non-numeric group name, and the checksum, since
 114  * these are all ignored by BusyBox tar. */
 115 struct TarInfo
 116 {
 117         int              tarFd;          /* An open file descriptor for reading from the tarball */
 118         char *           name;           /* File name */
 119         mode_t           mode;           /* Unix mode, including device bits. */
 120         uid_t            uid;            /* Numeric UID */
 121         gid_t            gid;            /* Numeric GID */
 122         size_t           size;           /* Size of file */
 123         time_t           mtime;          /* Last-modified time */
 124         enum TarFileType type;           /* Regular, directory, link, etc */
 125         char *           linkname;       /* Name for symbolic and hard links */
 126         long             devmajor;       /* Major number for special device */
 127         long             devminor;       /* Minor number for special device */
 128 };
 129 typedef struct TarInfo TarInfo;
 130
 131 /* Local procedures to restore files from a tar file.  */
 132 static int readTarFile(const char* tarName, int extractFlag, int listFlag,
 133                 int tostdoutFlag, int verboseFlag, char** extractList,
 134                 char** excludeList);
 135
 136
 137
 138 #ifdef BB_FEATURE_TAR_CREATE
 139 /* Local procedures to save files into a tar file.  */
 140 static int writeTarFile(const char* tarName, int verboseFlag, char **argv,
 141                 char** excludeList);
 142 #endif
 143
 144 extern int tar_main(int argc, char **argv)
 145 {
 146         char** excludeList=NULL;
 147         char** extractList=NULL;
 148 #if defined BB_FEATURE_TAR_EXCLUDE
 149         int excludeListSize=0;
 150         char *excludeFileName ="-";
 151         FILE *fileList;
 152         char file[256];
 153 #endif
 154         const char *tarName="-";
 155         int listFlag     = FALSE;
 156         int extractFlag  = FALSE;
 157         int createFlag   = FALSE;
 158         int verboseFlag  = FALSE;
 159         int tostdoutFlag = FALSE;
 160         int status       = FALSE;
 161         int firstOpt     = TRUE;
 162         int stopIt;
 163
 164
 165         if (argc <= 1)
 166                 usage(tar_usage);
 167
 168         while (*(++argv) && (**argv == '-' || firstOpt == TRUE)) {
 169                 firstOpt=FALSE;
 170                 stopIt=FALSE;
 171                 while (stopIt==FALSE && **argv) {
 172                         switch (*((*argv)++)) {
 173                                 case 'c':
 174                                         if (extractFlag == TRUE || listFlag == TRUE)
 175                                                 goto flagError;
 176                                         createFlag = TRUE;
 177                                         break;
 178                                 case 'x':
 179                                         if (listFlag == TRUE || createFlag == TRUE)
 180                                                 goto flagError;
 181                                         extractFlag = TRUE;
 182                                         break;
 183                                 case 't':
 184                                         if (extractFlag == TRUE || createFlag == TRUE)
 185                                                 goto flagError;
 186                                         listFlag = TRUE;
 187                                         break;
 188                                 case 'v':
 189                                         verboseFlag = TRUE;
 190                                         break;
 191                                 case 'O':
 192                                         tostdoutFlag = TRUE;
 193                                         break;
 194                                 case 'f':
 195                                         if (*tarName != '-')
 196                                                 error_msg_and_die( "Only one 'f' option allowed\n");
 197                                         tarName = *(++argv);
 198                                         if (tarName == NULL)
 199                                                 error_msg_and_die( "Option requires an argument: No file specified\n");
 200                                         stopIt=TRUE;
 201                                         break;
 202 #if defined BB_FEATURE_TAR_EXCLUDE
 203                                 case 'e':
 204                                         if (strcmp(*argv, "xclude")==0) {
 205                                                 excludeList=xrealloc( excludeList, sizeof(char**) * (excludeListSize+2));
 206                                                 excludeList[excludeListSize] = *(++argv);
 207                                                 if (excludeList[excludeListSize] == NULL)
 208                                                         error_msg_and_die( "Option requires an argument: No file specified\n");
 209                                                 /* Remove leading "/"s */
 210                                                 if (*excludeList[excludeListSize] =='/')
 211                                                         excludeList[excludeListSize] = (excludeList[excludeListSize])+1;
 212                                                 /* Tack a NULL onto the end of the list */
 213                                                 excludeList[++excludeListSize] = NULL;
 214                                                 stopIt=TRUE;
 215                                                 break;
 216                                         }
 217                                 case 'X':
 218                                        if (*excludeFileName != '-')
 219                                                error_msg_and_die("Only one 'X' option allowed\n");
 220                                        excludeFileName = *(++argv);
 221                                        if  (excludeFileName == NULL)
 222                                                error_msg_and_die("Option requires an argument: No file specified\n");
 223                                        fileList = fopen (excludeFileName, "rt");
 224                                        if (! fileList)
 225                                                error_msg_and_die("Exclude file: file not found\n");
 226                                        while (!feof(fileList)) {
 227                                                fscanf(fileList, "%s", file);
 228                                                excludeList=xrealloc( excludeList, sizeof(char**) * (excludeListSize+2));
 229                                                excludeList[excludeListSize] = malloc(sizeof(char) * (strlen(file)+1));
 230                                                strcpy(excludeList[excludeListSize],file);
 231                                                /* Remove leading "/"s */
 232                                                if (*excludeList[excludeListSize] == '/')
 233                                                        excludeList[excludeListSize] = (excludeList[excludeListSize])+1;
 234                                                /* Tack a NULL onto the end of the list */
 235                                                        excludeList[++excludeListSize] = NULL;
 236                                        }
 237
 238                                        fclose(fileList);
 239                                        stopIt=TRUE;
 240                                        break;
 241 #endif
 242                                 case '-':
 243                                                 break;
 244                                 default:
 245                                         usage(tar_usage);
 246                         }
 247                 }
 248         }
 249
 250         /*
 251          * Do the correct type of action supplying the rest of the
 252          * command line arguments as the list of files to process.
 253          */
 254         if (createFlag == TRUE) {
 255 #ifndef BB_FEATURE_TAR_CREATE
 256                 error_msg_and_die( "This version of tar was not compiled with tar creation support.\n");
 257 #else
 258                 status = writeTarFile(tarName, verboseFlag, argv, excludeList);
 259 #endif
 260         }
 261         if (listFlag == TRUE || extractFlag == TRUE) {
 262                 if (*argv)
 263                         extractList = argv;
 264                 status = readTarFile(tarName, extractFlag, listFlag, tostdoutFlag,
 265                                         verboseFlag, extractList, excludeList);
 266         }
 267
 268         if (status == TRUE)
 269                 return EXIT_SUCCESS;
 270         else
 271                 return EXIT_FAILURE;
 272
 273   flagError:
 274         error_msg_and_die( "Exactly one of 'c', 'x' or 't' must be specified\n");
 275 }
 276
 277 static void
 278 fixUpPermissions(TarInfo *header)
 279 {
 280         struct utimbuf t;
 281         /* Now set permissions etc for the new file */
 282         chown(header->name, header->uid, header->gid);
 283         chmod(header->name, header->mode);
 284         /* Reset the time */
 285         t.actime = time(0);
 286         t.modtime = header->mtime;
 287         utime(header->name, &t);
 288 }
 289
 290 static int
 291 tarExtractRegularFile(TarInfo *header, int extractFlag, int tostdoutFlag)
 292 {
 293         size_t  writeSize;
 294         size_t  readSize;
 295         size_t  actualWriteSz;
 296         char    buffer[BUFSIZ];
 297         size_t  size = header->size;
 298         int outFd=fileno(stdout);
 299
 300         /* Open the file to be written, if a file is supposed to be written */
 301         if (extractFlag==TRUE && tostdoutFlag==FALSE) {
 302                 /* Create the path to the file, just in case it isn't there...
 303                  * This should not screw up path permissions or anything. */
 304                 create_path(header->name, 0777);
 305                 if ((outFd=open(header->name, O_CREAT|O_TRUNC|O_WRONLY,
 306                                                 header->mode & ~S_IFMT)) < 0) {
 307                         error_msg(io_error, header->name, strerror(errno));
 308                         return( FALSE);
 309                 }
 310         }
 311
 312         /* Write out the file, if we are supposed to be doing that */
 313         while ( size > 0 ) {
 314                 actualWriteSz=0;
 315                 if ( size > sizeof(buffer) )
 316                         writeSize = readSize = sizeof(buffer);
 317                 else {
 318                         int mod = size % 512;
 319                         if ( mod != 0 )
 320                                 readSize = size + (512 - mod);
 321                         else
 322                                 readSize = size;
 323                         writeSize = size;
 324                 }
 325                 if ( (readSize = full_read(header->tarFd, buffer, readSize)) <= 0 ) {
 326                         /* Tarball seems to have a problem */
 327                         error_msg("Unexpected EOF in archive\n");
 328                         return( FALSE);
 329                 }
 330                 if ( readSize < writeSize )
 331                         writeSize = readSize;
 332
 333                 /* Write out the file, if we are supposed to be doing that */
 334                 if (extractFlag==TRUE) {
 335
 336                         if ((actualWriteSz=full_write(outFd, buffer, writeSize)) != writeSize ) {
 337                                 /* Output file seems to have a problem */
 338                                 error_msg(io_error, header->name, strerror(errno));
 339                                 return( FALSE);
 340                         }
 341                 } else {
 342                         actualWriteSz=writeSize;
 343                 }
 344
 345                 size -= actualWriteSz;
 346         }
 347
 348         /* Now we are done writing the file out, so try
 349          * and fix up the permissions and whatnot */
 350         if (extractFlag==TRUE && tostdoutFlag==FALSE) {
 351                 close(outFd);
 352                 fixUpPermissions(header);
 353         }
 354         return( TRUE);
 355 }
 356
 357 static int
 358 tarExtractDirectory(TarInfo *header, int extractFlag, int tostdoutFlag)
 359 {
 360
 361         if (extractFlag==FALSE || tostdoutFlag==TRUE)
 362                 return( TRUE);
 363
 364         if (create_path(header->name, header->mode) != TRUE) {
 365                 error_msg("%s: Cannot mkdir: %s\n",
 366                                 header->name, strerror(errno));
 367                 return( FALSE);
 368         }
 369         /* make the final component, just in case it was
 370          * omitted by create_path() (which will skip the
 371          * directory if it doesn't have a terminating '/') */
 372         if (mkdir(header->name, header->mode) == 0) {
 373                 fixUpPermissions(header);
 374         }
 375         return( TRUE);
 376 }
 377
 378 static int
 379 tarExtractHardLink(TarInfo *header, int extractFlag, int tostdoutFlag)
 380 {
 381         if (extractFlag==FALSE || tostdoutFlag==TRUE)
 382                 return( TRUE);
 383
 384         if (link(header->linkname, header->name) < 0) {
 385                 error_msg("%s: Cannot create hard link to '%s': %s\n",
 386                                 header->name, header->linkname, strerror(errno));
 387                 return( FALSE);
 388         }
 389
 390         /* Now set permissions etc for the new directory */
 391         fixUpPermissions(header);
 392         return( TRUE);
 393 }
 394
 395 static int
 396 tarExtractSymLink(TarInfo *header, int extractFlag, int tostdoutFlag)
 397 {
 398         if (extractFlag==FALSE || tostdoutFlag==TRUE)
 399                 return( TRUE);
 400
 401 #ifdef  S_ISLNK
 402         if (symlink(header->linkname, header->name) < 0) {
 403                 error_msg("%s: Cannot create symlink to '%s': %s\n",
 404                                 header->name, header->linkname, strerror(errno));
 405                 return( FALSE);
 406         }
 407         /* Try to change ownership of the symlink.
 408          * If libs doesn't support that, don't bother.
 409          * Changing the pointed-to-file is the Wrong Thing(tm).
 410          */
 411 #if (__GLIBC__ >= 2) && (__GLIBC_MINOR__ >= 1)
 412         lchown(header->name, header->uid, header->gid);
 413 #endif
 414
 415         /* Do not change permissions or date on symlink,
 416          * since it changes the pointed to file instead.  duh. */
 417 #else
 418         error_msg("%s: Cannot create symlink to '%s': %s\n",
 419                         header->name, header->linkname,
 420                         "symlinks not supported");
 421 #endif
 422         return( TRUE);
 423 }
 424
 425 static int
 426 tarExtractSpecial(TarInfo *header, int extractFlag, int tostdoutFlag)
 427 {
 428         if (extractFlag==FALSE || tostdoutFlag==TRUE)
 429                 return( TRUE);
 430
 431         if (S_ISCHR(header->mode) || S_ISBLK(header->mode) || S_ISSOCK(header->mode)) {
 432                 if (mknod(header->name, header->mode, makedev(header->devmajor, header->devminor)) < 0) {
 433                         error_msg("%s: Cannot mknod: %s\n",
 434                                 header->name, strerror(errno));
 435                         return( FALSE);
 436                 }
 437         } else if (S_ISFIFO(header->mode)) {
 438                 if (mkfifo(header->name, header->mode) < 0) {
 439                         error_msg("%s: Cannot mkfifo: %s\n",
 440                                 header->name, strerror(errno));
 441                         return( FALSE);
 442                 }
 443         }
 444
 445         /* Now set permissions etc for the new directory */
 446         fixUpPermissions(header);
 447         return( TRUE);
 448 }
 449
 450 /* Read an octal value in a field of the specified width, with optional
 451  * spaces on both sides of the number and with an optional null character
 452  * at the end.  Returns -1 on an illegal format.  */
 453 static long getOctal(const char *cp, int size)
 454 {
 455         long val = 0;
 456
 457         for(;(size > 0) && (*cp == ' '); cp++, size--);
 458         if ((size == 0) || !is_octal(*cp))
 459                 return -1;
 460         for(; (size > 0) && is_octal(*cp); size--) {
 461                 val = val * 8 + *cp++ - '0';
 462         }
 463         for (;(size > 0) && (*cp == ' '); cp++, size--);
 464         if ((size > 0) && *cp)
 465                 return -1;
 466         return val;
 467 }
 468
 469
 470 /* Parse the tar header and fill in the nice struct with the details */
 471 static int
 472 readTarHeader(struct TarHeader *rawHeader, struct TarInfo *header)
 473 {
 474         int i;
 475         long chksum, sum=0;
 476         unsigned char *s = (unsigned char *)rawHeader;
 477
 478         header->name  = rawHeader->name;
 479         /* Check for and relativify any absolute paths */
 480         if ( *(header->name) == '/' ) {
 481                 static int alreadyWarned=FALSE;
 482
 483                 while (*(header->name) == '/')
 484                         ++*(header->name);
 485
 486                 if (alreadyWarned == FALSE) {
 487                         error_msg("Removing leading '/' from member names\n");
 488                         alreadyWarned = TRUE;
 489                 }
 490         }
 491
 492         header->mode  = getOctal(rawHeader->mode, sizeof(rawHeader->mode));
 493         header->uid   =  getOctal(rawHeader->uid, sizeof(rawHeader->uid));
 494         header->gid   =  getOctal(rawHeader->gid, sizeof(rawHeader->gid));
 495         header->size  = getOctal(rawHeader->size, sizeof(rawHeader->size));
 496         header->mtime = getOctal(rawHeader->mtime, sizeof(rawHeader->mtime));
 497         chksum = getOctal(rawHeader->chksum, sizeof(rawHeader->chksum));
 498         header->type  = rawHeader->typeflag;
 499         header->linkname  = rawHeader->linkname;
 500         header->devmajor  = getOctal(rawHeader->devmajor, sizeof(rawHeader->devmajor));
 501         header->devminor  = getOctal(rawHeader->devminor, sizeof(rawHeader->devminor));
 502
 503         /* Check the checksum */
 504         for (i = sizeof(*rawHeader); i-- != 0;) {
 505                 sum += *s++;
 506         }
 507         /* Remove the effects of the checksum field (replace
 508          * with blanks for the purposes of the checksum) */
 509         s = rawHeader->chksum;
 510         for (i = sizeof(rawHeader->chksum) ; i-- != 0;) {
 511                 sum -= *s++;
 512         }
 513         sum += ' ' * sizeof(rawHeader->chksum);
 514         if (sum == chksum )
 515                 return ( TRUE);
 516         return( FALSE);
 517 }
 518
 519
 520 /*
 521  * Read a tar file and extract or list the specified files within it.
 522  * If the list is empty than all files are extracted or listed.
 523  */
 524 static int readTarFile(const char* tarName, int extractFlag, int listFlag,
 525                 int tostdoutFlag, int verboseFlag, char** extractList,
 526                 char** excludeList)
 527 {
 528         int status, tarFd=-1;
 529         int errorFlag=FALSE;
 530         int skipNextHeaderFlag=FALSE;
 531         TarHeader rawHeader;
 532         TarInfo header;
 533         char** tmpList;
 534
 535         /* Open the tar file for reading.  */
 536         if (!strcmp(tarName, "-"))
 537                 tarFd = fileno(stdin);
 538         else
 539                 tarFd = open(tarName, O_RDONLY);
 540         if (tarFd < 0) {
 541                 error_msg( "Error opening '%s': %s\n", tarName, strerror(errno));
 542                 return ( FALSE);
 543         }
 544
 545         /* Set the umask for this process so it doesn't
 546          * screw up permission setting for us later. */
 547         umask(0);
 548
 549         /* Read the tar file, and iterate over it one file at a time */
 550         while ( (status = full_read(tarFd, (char*)&rawHeader, TAR_BLOCK_SIZE)) == TAR_BLOCK_SIZE ) {
 551
 552                 /* Try to read the header */
 553                 if ( readTarHeader(&rawHeader, &header) == FALSE ) {
 554                         if ( *(header.name) == '\0' ) {
 555                                 goto endgame;
 556                         } else {
 557                                 errorFlag=TRUE;
 558                                 error_msg("Bad tar header, skipping\n");
 559                                 continue;
 560                         }
 561                 }
 562                 if ( *(header.name) == '\0' )
 563                                 goto endgame;
 564                 header.tarFd = tarFd;
 565
 566                 /* Skip funky extra GNU headers that precede long files */
 567                 if ( (header.type == GNULONGNAME) || (header.type == GNULONGLINK) ) {
 568                         skipNextHeaderFlag=TRUE;
 569                         if (tarExtractRegularFile(&header, FALSE, FALSE) == FALSE)
 570                                 errorFlag = TRUE;
 571                         continue;
 572                 }
 573                 if ( skipNextHeaderFlag == TRUE ) {
 574                         skipNextHeaderFlag=FALSE;
 575                         error_msg(name_longer_than_foo, NAME_SIZE);
 576                         if (tarExtractRegularFile(&header, FALSE, FALSE) == FALSE)
 577                                 errorFlag = TRUE;
 578                         continue;
 579                 }
 580
 581 #if defined BB_FEATURE_TAR_EXCLUDE
 582                 {
 583                         int skipFlag=FALSE;
 584                         /* Check for excluded files....  */
 585                         for (tmpList=excludeList; tmpList && *tmpList; tmpList++) {
 586                                 /* Do some extra hoop jumping for when directory names
 587                                  * end in '/' but the entry in tmpList doesn't */
 588                                 if (strncmp( *tmpList, header.name, strlen(*tmpList))==0 || (
 589                                                         header.name[strlen(header.name)-1]=='/'
 590                                                         && strncmp( *tmpList, header.name,
 591                                                                 MIN(strlen(header.name)-1, strlen(*tmpList)))==0)) {
 592                                         /* If it is a regular file, pretend to extract it with
 593                                          * the extractFlag set to FALSE, so the junk in the tarball
 594                                          * is properly skipped over */
 595                                         if ( header.type==REGTYPE || header.type==REGTYPE0 ) {
 596                                                 if (tarExtractRegularFile(&header, FALSE, FALSE) == FALSE)
 597                                                         errorFlag = TRUE;
 598                                         }
 599                                         skipFlag=TRUE;
 600                                         break;
 601                                 }
 602                         }
 603                         /* There are not the droids you're looking for, move along */
 604                         if (skipFlag==TRUE)
 605                                 continue;
 606                 }
 607 #endif
 608                 if (extractList != NULL) {
 609                         int skipFlag = TRUE;
 610                         for (tmpList = extractList; *tmpList != NULL; tmpList++) {
 611                                 if (strncmp( *tmpList, header.name, strlen(*tmpList))==0 || (
 612                                                         header.name[strlen(header.name)-1]=='/'
 613                                                         && strncmp( *tmpList, header.name,
 614                                                                 MIN(strlen(header.name)-1, strlen(*tmpList)))==0)) {
 615                                         /* If it is a regular file, pretend to extract it with
 616                                          * the extractFlag set to FALSE, so the junk in the tarball
 617                                          * is properly skipped over */
 618                                         skipFlag = FALSE;
 619                                         memmove(extractList+1, extractList,
 620                                                                 sizeof(*extractList)*(tmpList-extractList));
 621                                         extractList++;
 622                                         break;
 623                                 }
 624                         }
 625                         /* There are not the droids you're looking for, move along */
 626                         if (skipFlag == TRUE) {
 627                                 if ( header.type==REGTYPE || header.type==REGTYPE0 )
 628                                         if (tarExtractRegularFile(&header, FALSE, FALSE) == FALSE)
 629                                                 errorFlag = TRUE;
 630                                 continue;
 631                         }
 632                 }
 633
 634                 if (listFlag == TRUE) {
 635                         /* Special treatment if the list (-t) flag is on */
 636                         if (verboseFlag == TRUE) {
 637                                 int len, len1;
 638                                 char buf[35];
 639                                 struct tm *tm = localtime (&(header.mtime));
 640
 641                                 len=printf("%s ", mode_string(header.mode));
 642                                 memset(buf, 0, 8*sizeof(char));
 643                                 my_getpwuid(buf, header.uid);
 644                                 if (! *buf)
 645                                         len+=printf("%d", header.uid);
 646                                 else
 647                                         len+=printf("%s", buf);
 648                                 memset(buf, 0, 8*sizeof(char));
 649                                 my_getgrgid(buf, header.gid);
 650                                 if (! *buf)
 651                                         len+=printf("/%-d ", header.gid);
 652                                 else
 653                                         len+=printf("/%-s ", buf);
 654
 655                                 if (header.type==CHRTYPE || header.type==BLKTYPE) {
 656                                         len1=snprintf(buf, sizeof(buf), "%ld,%-ld ",
 657                                                         header.devmajor, header.devminor);
 658                                 } else {
 659                                         len1=snprintf(buf, sizeof(buf), "%lu ", (long)header.size);
 660                                 }
 661                                 /* Jump through some hoops to make the columns match up */
 662                                 for(;(len+len1)<31;len++)
 663                                         printf(" ");
 664                                 printf(buf);
 665
 666                                 /* Use ISO 8610 time format */
 667                                 if (tm) {
 668                                         printf ("%04d-%02d-%02d %02d:%02d:%02d ",
 669                                                         tm->tm_year + 1900, tm->tm_mon + 1, tm->tm_mday,
 670                                                         tm->tm_hour, tm->tm_min, tm->tm_sec);
 671                                 }
 672                         }
 673                         printf("%s", header.name);
 674                         if (verboseFlag == TRUE) {
 675                                 if (header.type==LNKTYPE)       /* If this is a link, say so */
 676                                         printf(" link to %s", header.linkname);
 677                                 else if (header.type==SYMTYPE)
 678                                         printf(" -> %s", header.linkname);
 679                         }
 680                         printf("\n");
 681                 }
 682
 683                 /* List contents if we are supposed to do that */
 684                 if (verboseFlag == TRUE && extractFlag == TRUE) {
 685                         /* Now the normal listing */
 686                         FILE *vbFd = stdout;
 687                         if (tostdoutFlag == TRUE)       // If the archive goes to stdout, verbose to stderr
 688                                 vbFd = stderr;
 689                         fprintf(vbFd, "%s\n", header.name);
 690                 }
 691
 692                 /* Remove files if we would overwrite them */
 693                 if (extractFlag == TRUE && tostdoutFlag == FALSE)
 694                         unlink(header.name);
 695
 696                 /* If we got here, we can be certain we have a legitimate
 697                  * header to work with.  So work with it.  */
 698                 switch ( header.type ) {
 699                         case REGTYPE:
 700                         case REGTYPE0:
 701                                 /* If the name ends in a '/' then assume it is
 702                                  * supposed to be a directory, and fall through */
 703                                 if (header.name[strlen(header.name)-1] != '/') {
 704                                         if (tarExtractRegularFile(&header, extractFlag, tostdoutFlag)==FALSE)
 705                                                 errorFlag=TRUE;
 706                                         break;
 707                                 }
 708                         case DIRTYPE:
 709                                 if (tarExtractDirectory( &header, extractFlag, tostdoutFlag)==FALSE)
 710                                         errorFlag=TRUE;
 711                                 break;
 712                         case LNKTYPE:
 713                                 if (tarExtractHardLink( &header, extractFlag, tostdoutFlag)==FALSE)
 714                                         errorFlag=TRUE;
 715                                 break;
 716                         case SYMTYPE:
 717                                 if (tarExtractSymLink( &header, extractFlag, tostdoutFlag)==FALSE)
 718                                         errorFlag=TRUE;
 719                                 break;
 720                         case CHRTYPE:
 721                         case BLKTYPE:
 722                         case FIFOTYPE:
 723                                 if (tarExtractSpecial( &header, extractFlag, tostdoutFlag)==FALSE)
 724                                         errorFlag=TRUE;
 725                                 break;
 726 #if 0
 727                         /* Handled earlier */
 728                         case GNULONGNAME:
 729                         case GNULONGLINK:
 730                                 skipNextHeaderFlag=TRUE;
 731                                 break;
 732 #endif
 733                         default:
 734                                 error_msg("Unknown file type '%c' in tar file\n", header.type);
 735                                 close( tarFd);
 736                                 return( FALSE);
 737                 }
 738         }
 739         close(tarFd);
 740         if (status > 0) {
 741                 /* Bummer - we read a partial header */
 742                 error_msg( "Error reading '%s': %s\n", tarName, strerror(errno));
 743                 return ( FALSE);
 744         }
 745         else if (errorFlag==TRUE) {
 746                 error_msg( "Error exit delayed from previous errors\n");
 747                 return( FALSE);
 748         } else
 749                 return( status);
 750
 751         /* Stuff to do when we are done */
 752 endgame:
 753         close( tarFd);
 754         if (extractList != NULL) {
 755                 for (; *extractList != NULL; extractList++) {
 756                         error_msg("%s: Not found in archive\n", *extractList);
 757                         errorFlag = TRUE;
 758                 }
 759         }
 760         if ( *(header.name) == '\0' ) {
 761                 if (errorFlag==TRUE)
 762                         error_msg( "Error exit delayed from previous errors\n");
 763                 else
 764                         return( TRUE);
 765         }
 766         return( FALSE);
 767 }
 768
 769
 770 #ifdef BB_FEATURE_TAR_CREATE
 771
 772 /*
 773 ** writeTarFile(),  writeFileToTarball(), and writeTarHeader() are
 774 ** the only functions that deal with the HardLinkInfo structure.
 775 ** Even these functions use the xxxHardLinkInfo() functions.
 776 */
 777 typedef struct HardLinkInfo HardLinkInfo;
 778 struct HardLinkInfo
 779 {
 780         HardLinkInfo *next;           /* Next entry in list */
 781         dev_t dev;                    /* Device number */
 782         ino_t ino;                    /* Inode number */
 783         short linkCount;              /* (Hard) Link Count */
 784         char name[1];                 /* Start of filename (must be last) */
 785 };
 786
 787 /* Some info to be carried along when creating a new tarball */
 788 struct TarBallInfo
 789 {
 790         char* fileName;               /* File name of the tarball */
 791         int tarFd;                    /* Open-for-write file descriptor
 792                                                                          for the tarball */
 793         struct stat statBuf;          /* Stat info for the tarball, letting
 794                                                                          us know the inode and device that the
 795                                                                          tarball lives, so we can avoid trying
 796                                                                          to include the tarball into itself */
 797         int verboseFlag;              /* Whether to print extra stuff or not */
 798         char** excludeList;           /* List of files to not include */
 799         HardLinkInfo *hlInfoHead;     /* Hard Link Tracking Information */
 800         HardLinkInfo *hlInfo;         /* Hard Link Info for the current file */
 801 };
 802 typedef struct TarBallInfo TarBallInfo;
 803
 804
 805 /* Might be faster (and bigger) if the dev/ino were stored in numeric order;) */
 806 static void
 807 addHardLinkInfo (HardLinkInfo **hlInfoHeadPtr, dev_t dev, ino_t ino,
 808                 short linkCount, const char *name)
 809 {
 810         /* Note: hlInfoHeadPtr can never be NULL! */
 811         HardLinkInfo *hlInfo;
 812
 813         hlInfo = (HardLinkInfo *)xmalloc(sizeof(HardLinkInfo)+strlen(name)+1);
 814         if (hlInfo) {
 815                 hlInfo->next = *hlInfoHeadPtr;
 816                 *hlInfoHeadPtr = hlInfo;
 817                 hlInfo->dev = dev;
 818                 hlInfo->ino = ino;
 819                 hlInfo->linkCount = linkCount;
 820                 strcpy(hlInfo->name, name);
 821         }
 822         return;
 823 }
 824
 825 static void
 826 freeHardLinkInfo (HardLinkInfo **hlInfoHeadPtr)
 827 {
 828         HardLinkInfo *hlInfo = NULL;
 829         HardLinkInfo *hlInfoNext = NULL;
 830
 831         if (hlInfoHeadPtr) {
 832                 hlInfo = *hlInfoHeadPtr;
 833                 while (hlInfo) {
 834                         hlInfoNext = hlInfo->next;
 835                         free(hlInfo);
 836                         hlInfo = hlInfoNext;
 837                 }
 838                 *hlInfoHeadPtr = NULL;
 839         }
 840         return;
 841 }
 842
 843 /* Might be faster (and bigger) if the dev/ino were stored in numeric order;) */
 844 static HardLinkInfo *
 845 findHardLinkInfo (HardLinkInfo *hlInfo, dev_t dev, ino_t ino)
 846 {
 847         while(hlInfo) {
 848                 if ((ino == hlInfo->ino) && (dev == hlInfo->dev))
 849                         break;
 850                 hlInfo = hlInfo->next;
 851         }
 852         return(hlInfo);
 853 }
 854
 855 /* Put an octal string into the specified buffer.
 856  * The number is zero and space padded and possibly null padded.
 857  * Returns TRUE if successful.  */
 858 static int putOctal (char *cp, int len, long value)
 859 {
 860         int tempLength;
 861         char tempBuffer[32];
 862         char *tempString = tempBuffer;
 863
 864         /* Create a string of the specified length with an initial space,
 865          * leading zeroes and the octal number, and a trailing null.  */
 866         sprintf (tempString, "%0*lo", len - 1, value);
 867
 868         /* If the string is too large, suppress the leading space.  */
 869         tempLength = strlen (tempString) + 1;
 870         if (tempLength > len) {
 871                 tempLength--;
 872                 tempString++;
 873         }
 874
 875         /* If the string is still too large, suppress the trailing null.  */
 876         if (tempLength > len)
 877                 tempLength--;
 878
 879         /* If the string is still too large, fail.  */
 880         if (tempLength > len)
 881                 return FALSE;
 882
 883         /* Copy the string to the field.  */
 884         memcpy (cp, tempString, len);
 885
 886         return TRUE;
 887 }
 888
 889 /* Write out a tar header for the specified file/directory/whatever */
 890 static int
 891 writeTarHeader(struct TarBallInfo *tbInfo, const char *fileName, struct stat *statbuf)
 892 {
 893         long chksum=0;
 894         struct TarHeader header;
 895 #if defined BB_FEATURE_TAR_EXCLUDE
 896         char** tmpList;
 897 #endif
 898         const unsigned char *cp = (const unsigned char *) &header;
 899         ssize_t size = sizeof(struct TarHeader);
 900
 901         memset( &header, 0, size);
 902
 903         if (*fileName=='/') {
 904                 static int alreadyWarned=FALSE;
 905                 if (alreadyWarned==FALSE) {
 906                         error_msg("Removing leading '/' from member names\n");
 907                         alreadyWarned=TRUE;
 908                 }
 909                 strncpy(header.name, fileName+1, sizeof(header.name));
 910         }
 911         else {
 912                 strncpy(header.name, fileName, sizeof(header.name));
 913         }
 914
 915 #if defined BB_FEATURE_TAR_EXCLUDE
 916         /* Check for excluded files....  */
 917         for (tmpList=tbInfo->excludeList; tmpList && *tmpList; tmpList++) {
 918                 /* Do some extra hoop jumping for when directory names
 919                  * end in '/' but the entry in tmpList doesn't */
 920                 if (strncmp( *tmpList, header.name, strlen(*tmpList))==0 || (
 921                                         header.name[strlen(header.name)-1]=='/'
 922                                         && strncmp( *tmpList, header.name,
 923                                                 MIN(strlen(header.name)-1, strlen(*tmpList)))==0)) {
 924                         /* Set the mode to something that is not a regular file, thereby
 925                          * faking out writeTarFile into thinking that nothing further need
 926                          * be done for this file.  Yes, I know this is ugly, but it works. */
 927                         statbuf->st_mode = 0;
 928                         return( TRUE);
 929                 }
 930         }
 931 #endif
 932
 933         putOctal(header.mode, sizeof(header.mode), statbuf->st_mode);
 934         putOctal(header.uid, sizeof(header.uid), statbuf->st_uid);
 935         putOctal(header.gid, sizeof(header.gid), statbuf->st_gid);
 936         putOctal(header.size, sizeof(header.size), 0); /* Regular file size is handled later */
 937         putOctal(header.mtime, sizeof(header.mtime), statbuf->st_mtime);
 938         strncpy(header.magic, TAR_MAGIC TAR_VERSION,
 939                         TAR_MAGIC_LEN + TAR_VERSION_LEN );
 940
 941         /* Enter the user and group names (default to root if it fails) */
 942         my_getpwuid(header.uname, statbuf->st_uid);
 943         if (! *header.uname)
 944                 strcpy(header.uname, "root");
 945         my_getgrgid(header.gname, statbuf->st_gid);
 946         if (! *header.uname)
 947                 strcpy(header.uname, "root");
 948
 949         if (tbInfo->hlInfo) {
 950                 /* This is a hard link */
 951                 header.typeflag = LNKTYPE;
 952                 strncpy(header.linkname, tbInfo->hlInfo->name, sizeof(header.linkname));
 953         } else if (S_ISLNK(statbuf->st_mode)) {
 954                 int link_size=0;
 955                 char buffer[BUFSIZ];
 956                 header.typeflag  = SYMTYPE;
 957                 link_size = readlink(fileName, buffer, sizeof(buffer) - 1);
 958                 if ( link_size < 0) {
 959                         error_msg("Error reading symlink '%s': %s\n", header.name, strerror(errno));
 960                         return ( FALSE);
 961                 }
 962                 buffer[link_size] = '\0';
 963                 strncpy(header.linkname, buffer, sizeof(header.linkname));
 964         } else if (S_ISDIR(statbuf->st_mode)) {
 965                 header.typeflag  = DIRTYPE;
 966                 strncat(header.name, "/", sizeof(header.name));
 967         } else if (S_ISCHR(statbuf->st_mode)) {
 968                 header.typeflag  = CHRTYPE;
 969                 putOctal(header.devmajor, sizeof(header.devmajor), MAJOR(statbuf->st_rdev));
 970                 putOctal(header.devminor, sizeof(header.devminor), MINOR(statbuf->st_rdev));
 971         } else if (S_ISBLK(statbuf->st_mode)) {
 972                 header.typeflag  = BLKTYPE;
 973                 putOctal(header.devmajor, sizeof(header.devmajor), MAJOR(statbuf->st_rdev));
 974                 putOctal(header.devminor, sizeof(header.devminor), MINOR(statbuf->st_rdev));
 975         } else if (S_ISFIFO(statbuf->st_mode)) {
 976                 header.typeflag  = FIFOTYPE;
 977         } else if (S_ISREG(statbuf->st_mode)) {
 978                 header.typeflag  = REGTYPE;
 979                 putOctal(header.size, sizeof(header.size), statbuf->st_size);
 980         } else {
 981                 error_msg("%s: Unknown file type\n", fileName);
 982                 return ( FALSE);
 983         }
 984
 985         /* Calculate and store the checksum (i.e. the sum of all of the bytes of
 986          * the header).  The checksum field must be filled with blanks for the
 987          * calculation.  The checksum field is formatted differently from the
 988          * other fields: it has [6] digits, a null, then a space -- rather than
 989          * digits, followed by a null like the other fields... */
 990         memset(header.chksum, ' ', sizeof(header.chksum));
 991         cp = (const unsigned char *) &header;
 992         while (size-- > 0)
 993                 chksum += *cp++;
 994         putOctal(header.chksum, 7, chksum);
 995
 996         /* Now write the header out to disk */
 997         if ((size=full_write(tbInfo->tarFd, (char*)&header, sizeof(struct TarHeader))) < 0) {
 998                 error_msg(io_error, fileName, strerror(errno));
 999                 return ( FALSE);
1000         }
1001         /* Pad the header up to the tar block size */
1002         for (; size<TAR_BLOCK_SIZE; size++) {
1003                 write(tbInfo->tarFd, "\0", 1);
1004         }
1005         /* Now do the verbose thing (or not) */
1006         if (tbInfo->verboseFlag==TRUE) {
1007                 FILE *vbFd = stdout;
1008                 if (tbInfo->tarFd == fileno(stdout))    // If the archive goes to stdout, verbose to stderr
1009                         vbFd = stderr;
1010                 fprintf(vbFd, "%s\n", header.name);
1011         }
1012
1013         return ( TRUE);
1014 }
1015
1016
1017 static int writeFileToTarball(const char *fileName, struct stat *statbuf, void* userData)
1018 {
1019         struct TarBallInfo *tbInfo = (struct TarBallInfo *)userData;
1020
1021         /*
1022         ** Check to see if we are dealing with a hard link.
1023         ** If so -
1024         ** Treat the first occurance of a given dev/inode as a file while
1025         ** treating any additional occurances as hard links.  This is done
1026         ** by adding the file information to the HardLinkInfo linked list.
1027         */
1028         tbInfo->hlInfo = NULL;
1029         if (statbuf->st_nlink > 1) {
1030                 tbInfo->hlInfo = findHardLinkInfo(tbInfo->hlInfoHead, statbuf->st_dev,
1031                                 statbuf->st_ino);
1032                 if (tbInfo->hlInfo == NULL)
1033                         addHardLinkInfo (&tbInfo->hlInfoHead, statbuf->st_dev,
1034                                         statbuf->st_ino, statbuf->st_nlink, fileName);
1035         }
1036
1037         /* It is against the rules to archive a socket */
1038         if (S_ISSOCK(statbuf->st_mode)) {
1039                 error_msg("%s: socket ignored\n", fileName);
1040                 return( TRUE);
1041         }
1042
1043         /* It is a bad idea to store the archive we are in the process of creating,
1044          * so check the device and inode to be sure that this particular file isn't
1045          * the new tarball */
1046         if (tbInfo->statBuf.st_dev == statbuf->st_dev &&
1047                         tbInfo->statBuf.st_ino == statbuf->st_ino) {
1048                 error_msg("%s: file is the archive; skipping\n", fileName);
1049                 return( TRUE);
1050         }
1051
1052         if (strlen(fileName) >= NAME_SIZE) {
1053                 error_msg(name_longer_than_foo, NAME_SIZE);
1054                 return ( TRUE);
1055         }
1056
1057         if (writeTarHeader(tbInfo, fileName, statbuf)==FALSE) {
1058                 return( FALSE);
1059         }
1060
1061         /* Now, if the file is a regular file, copy it out to the tarball */
1062         if ((tbInfo->hlInfo == NULL)
1063         &&  (S_ISREG(statbuf->st_mode))) {
1064                 int  inputFileFd;
1065                 char buffer[BUFSIZ];
1066                 ssize_t size=0, readSize=0;
1067
1068                 /* open the file we want to archive, and make sure all is well */
1069                 if ((inputFileFd = open(fileName, O_RDONLY)) < 0) {
1070                         error_msg("%s: Cannot open: %s\n", fileName, strerror(errno));
1071                         return( FALSE);
1072                 }
1073
1074                 /* write the file to the archive */
1075                 while ( (size = full_read(inputFileFd, buffer, sizeof(buffer))) > 0 ) {
1076                         if (full_write(tbInfo->tarFd, buffer, size) != size ) {
1077                                 /* Output file seems to have a problem */
1078                                 error_msg(io_error, fileName, strerror(errno));
1079                                 return( FALSE);
1080                         }
1081                         readSize+=size;
1082                 }
1083                 if (size == -1) {
1084                         error_msg(io_error, fileName, strerror(errno));
1085                         return( FALSE);
1086                 }
1087                 /* Pad the file up to the tar block size */
1088                 for (; (readSize%TAR_BLOCK_SIZE) != 0; readSize++) {
1089                         write(tbInfo->tarFd, "\0", 1);
1090                 }
1091                 close( inputFileFd);
1092         }
1093
1094         return( TRUE);
1095 }
1096
1097 static int writeTarFile(const char* tarName, int verboseFlag, char **argv,
1098                 char** excludeList)
1099 {
1100         int tarFd=-1;
1101         int errorFlag=FALSE;
1102         ssize_t size;
1103         struct TarBallInfo tbInfo;
1104         tbInfo.verboseFlag = verboseFlag;
1105         tbInfo.hlInfoHead = NULL;
1106
1107         /* Make sure there is at least one file to tar up.  */
1108         if (*argv == NULL)
1109                 error_msg_and_die("Cowardly refusing to create an empty archive\n");
1110
1111         /* Open the tar file for writing.  */
1112         if (!strcmp(tarName, "-"))
1113                 tbInfo.tarFd = fileno(stdout);
1114         else
1115                 tbInfo.tarFd = open (tarName, O_WRONLY | O_CREAT | O_TRUNC, 0644);
1116         if (tbInfo.tarFd < 0) {
1117                 error_msg( "Error opening '%s': %s\n", tarName, strerror(errno));
1118                 freeHardLinkInfo(&tbInfo.hlInfoHead);
1119                 return ( FALSE);
1120         }
1121         tbInfo.excludeList=excludeList;
1122         /* Store the stat info for the tarball's file, so
1123          * can avoid including the tarball into itself....  */
1124         if (fstat(tbInfo.tarFd, &tbInfo.statBuf) < 0)
1125                 error_msg_and_die(io_error, tarName, strerror(errno));
1126
1127         /* Set the umask for this process so it doesn't
1128          * screw up permission setting for us later. */
1129         umask(0);
1130
1131         /* Read the directory/files and iterate over them one at a time */
1132         while (*argv != NULL) {
1133                 if (recursive_action(*argv++, TRUE, FALSE, FALSE,
1134                                         writeFileToTarball, writeFileToTarball,
1135                                         (void*) &tbInfo) == FALSE) {
1136                         errorFlag = TRUE;
1137                 }
1138         }
1139         /* Write two empty blocks to the end of the archive */
1140         for (size=0; size<(2*TAR_BLOCK_SIZE); size++) {
1141                 write(tbInfo.tarFd, "\0", 1);
1142         }
1143
1144         /* To be pedantically correct, we would check if the tarball
1145          * is smaller than 20 tar blocks, and pad it if it was smaller,
1146          * but that isn't necessary for GNU tar interoperability, and
1147          * so is considered a waste of space */
1148
1149         /* Hang up the tools, close up shop, head home */
1150         close(tarFd);
1151         if (errorFlag == TRUE) {
1152                 error_msg("Error exit delayed from previous errors\n");
1153                 freeHardLinkInfo(&tbInfo.hlInfoHead);
1154                 return(FALSE);
1155         }
1156         freeHardLinkInfo(&tbInfo.hlInfoHead);
1157         return( TRUE);
1158 }
1159
1160
1161 #endif
1162