blob: 925f621588d0313318a7c967f71b95f24c85d3b5 [file] [log] [blame]
/*
** Copyright 1998-2003 University of Illinois Board of Trustees
** Copyright 1998-2003 Mark D. Roth
** All rights reserved.
**
** extract.c - libtar code to extract a file from a tar archive
**
** Mark D. Roth <roth@uiuc.edu>
** Campus Information Technologies and Educational Services
** University of Illinois at Urbana-Champaign
*/
#include <libtarint/internal.h>
#include <stdio.h>
#include <libtar/compat.h>
#include <sys/types.h>
#include <fcntl.h>
#include <errno.h>
#if defined(_WIN32) && !defined(__CYGWIN__)
# ifdef _MSC_VER
# include <sys/utime.h>
# else
# include <utime.h>
# endif
# include <io.h>
# include <direct.h>
#else
# include <utime.h>
# include <sys/param.h>
#endif
#ifdef STDC_HEADERS
# include <stdlib.h>
# include <string.h>
#endif
#ifdef HAVE_UNISTD_H
# include <unistd.h>
#endif
#ifdef HAVE_SYS_MKDEV_H
# include <sys/mkdev.h>
#endif
struct linkname
{
char ln_save[TAR_MAXPATHLEN];
char ln_real[TAR_MAXPATHLEN];
};
typedef struct linkname linkname_t;
static int
tar_set_file_perms(TAR *t, char *realname)
{
mode_t mode;
uid_t uid;
gid_t gid;
struct utimbuf ut;
char *filename;
char *pathname = 0;
if (realname)
{
filename = realname;
}
else
{
pathname = th_get_pathname(t);
filename = pathname;
}
mode = th_get_mode(t);
uid = th_get_uid(t);
gid = th_get_gid(t);
ut.modtime = ut.actime = th_get_mtime(t);
/* change owner/group */
#ifndef WIN32
if (geteuid() == 0)
#ifdef HAVE_LCHOWN
if (lchown(filename, uid, gid) == -1)
{
# ifdef DEBUG
fprintf(stderr, "lchown(\"%s\", %d, %d): %s\n",
filename, uid, gid, strerror(errno));
# endif
#else /* ! HAVE_LCHOWN */
if (!TH_ISSYM(t) && chown(filename, uid, gid) == -1)
{
# ifdef DEBUG
fprintf(stderr, "chown(\"%s\", %d, %d): %s\n",
filename, uid, gid, strerror(errno));
# endif
#endif /* HAVE_LCHOWN */
if (pathname)
{
free(pathname);
}
return -1;
}
/* change access/modification time */
if (!TH_ISSYM(t) && utime(filename, &ut) == -1)
{
#ifdef DEBUG
perror("utime()");
#endif
if (pathname)
{
free(pathname);
}
return -1;
}
/* change permissions */
if (!TH_ISSYM(t) && chmod(filename, mode & 07777) == -1)
{
#ifdef DEBUG
perror("chmod()");
#endif
if (pathname)
{
free(pathname);
}
return -1;
}
#else /* WIN32 */
(void)filename;
(void)gid;
(void)uid;
(void)mode;
#endif /* WIN32 */
if (pathname)
{
free(pathname);
}
return 0;
}
/* switchboard */
int
tar_extract_file(TAR *t, char *realname)
{
int i;
linkname_t *lnp;
char *pathname;
if (t->options & TAR_NOOVERWRITE)
{
struct stat s;
#ifdef WIN32
if (stat(realname, &s) == 0 || errno != ENOENT)
#else
if (lstat(realname, &s) == 0 || errno != ENOENT)
#endif
{
errno = EEXIST;
return -1;
}
}
if (TH_ISDIR(t))
{
i = tar_extract_dir(t, realname);
if (i == 1)
i = 0;
}
#ifndef _WIN32
else if (TH_ISLNK(t))
i = tar_extract_hardlink(t, realname);
else if (TH_ISSYM(t))
i = tar_extract_symlink(t, realname);
else if (TH_ISCHR(t))
i = tar_extract_chardev(t, realname);
else if (TH_ISBLK(t))
i = tar_extract_blockdev(t, realname);
else if (TH_ISFIFO(t))
i = tar_extract_fifo(t, realname);
#endif
else /* if (TH_ISREG(t)) */
i = tar_extract_regfile(t, realname);
if (i != 0)
return i;
i = tar_set_file_perms(t, realname);
if (i != 0)
return i;
lnp = (linkname_t *)calloc(1, sizeof(linkname_t));
if (lnp == NULL)
return -1;
pathname = th_get_pathname(t);
strlcpy(lnp->ln_save, pathname, sizeof(lnp->ln_save));
strlcpy(lnp->ln_real, realname, sizeof(lnp->ln_real));
#ifdef DEBUG
printf("tar_extract_file(): calling libtar_hash_add(): key=\"%s\", "
"value=\"%s\"\n", pathname, realname);
#endif
if (pathname)
{
free(pathname);
}
if (libtar_hash_add(t->h, lnp) != 0)
return -1;
return 0;
}
/* extract regular file */
int
tar_extract_regfile(TAR *t, char *realname)
{
mode_t mode;
size_t size;
uid_t uid;
gid_t gid;
int fdout;
ssize_t i, k;
char buf[T_BLOCKSIZE];
char *filename;
char *pathname = 0;
#ifdef DEBUG
printf("==> tar_extract_regfile(t=0x%lx, realname=\"%s\")\n", t,
realname);
#endif
if (!TH_ISREG(t))
{
errno = EINVAL;
return -1;
}
if (realname)
{
filename = realname;
}
else
{
pathname = th_get_pathname(t);
filename = pathname;
}
mode = th_get_mode(t);
size = th_get_size(t);
uid = th_get_uid(t);
gid = th_get_gid(t);
/* Make a copy of the string because dirname and mkdirhier may modify the
* string */
strncpy(buf, filename, sizeof(buf)-1);
buf[sizeof(buf)-1] = 0;
if (mkdirhier(dirname(buf)) == -1)
{
if (pathname)
{
free(pathname);
}
return -1;
}
#ifdef DEBUG
printf(" ==> extracting: %s (mode %04o, uid %d, gid %d, %d bytes)\n",
filename, mode, uid, gid, size);
#endif
fdout = open(filename, O_WRONLY | O_CREAT | O_TRUNC
#ifdef O_BINARY
| O_BINARY
#endif
, 0666);
if (fdout == -1)
{
#ifdef DEBUG
perror("open()");
#endif
if (pathname)
{
free(pathname);
}
return -1;
}
#if 0
/* change the owner. (will only work if run as root) */
if (fchown(fdout, uid, gid) == -1 && errno != EPERM)
{
#ifdef DEBUG
perror("fchown()");
#endif
if (pathname)
{
free(pathname);
}
return -1;
}
/* make sure the mode isn't inheritted from a file we're overwriting */
if (fchmod(fdout, mode & 07777) == -1)
{
#ifdef DEBUG
perror("fchmod()");
#endif
if (pathname)
{
free(pathname);
}
return -1;
}
#endif
/* extract the file */
for (i = size; i > 0; i -= T_BLOCKSIZE)
{
k = tar_block_read(t, buf);
if (k != T_BLOCKSIZE)
{
if (k != -1)
errno = EINVAL;
if (pathname)
{
free(pathname);
}
return -1;
}
/* write block to output file */
if (write(fdout, buf,
((i > T_BLOCKSIZE) ? T_BLOCKSIZE : (unsigned int)i)) == -1)
{
if (pathname)
{
free(pathname);
}
return -1;
}
}
/* close output file */
if (close(fdout) == -1)
{
if (pathname)
{
free(pathname);
}
return -1;
}
#ifdef DEBUG
printf("### done extracting %s\n", filename);
#endif
(void)filename;
(void)gid;
(void)uid;
(void)mode;
if (pathname)
{
free(pathname);
}
return 0;
}
/* skip regfile */
int
tar_skip_regfile(TAR *t)
{
ssize_t i, k;
size_t size;
char buf[T_BLOCKSIZE];
if (!TH_ISREG(t))
{
errno = EINVAL;
return -1;
}
size = th_get_size(t);
for (i = size; i > 0; i -= T_BLOCKSIZE)
{
k = tar_block_read(t, buf);
if (k != T_BLOCKSIZE)
{
if (k != -1)
errno = EINVAL;
return -1;
}
}
return 0;
}
/* hardlink */
int
tar_extract_hardlink(TAR * t, char *realname)
{
char *filename;
char *linktgt;
linkname_t *lnp;
libtar_hashptr_t hp;
char buf[T_BLOCKSIZE];
char *pathname = 0;
if (!TH_ISLNK(t))
{
errno = EINVAL;
return -1;
}
if (realname)
{
filename = realname;
}
else
{
pathname = th_get_pathname(t);
filename = pathname;
}
/* Make a copy of the string because dirname and mkdirhier may modify the
* string */
strncpy(buf, filename, sizeof(buf)-1);
buf[sizeof(buf)-1] = 0;
if (mkdirhier(dirname(buf)) == -1)
{
if (pathname)
{
free(pathname);
}
return -1;
}
libtar_hashptr_reset(&hp);
if (libtar_hash_getkey(t->h, &hp, th_get_linkname(t),
(libtar_matchfunc_t)libtar_str_match) != 0)
{
lnp = (linkname_t *)libtar_hashptr_data(&hp);
linktgt = lnp->ln_real;
}
else
linktgt = th_get_linkname(t);
#ifdef DEBUG
printf(" ==> extracting: %s (link to %s)\n", filename, linktgt);
#endif
#ifndef WIN32
if (link(linktgt, filename) == -1)
#else
(void)linktgt;
#endif
{
#ifdef DEBUG
perror("link()");
#endif
if (pathname)
{
free(pathname);
}
return -1;
}
#ifndef WIN32
if (pathname)
{
free(pathname);
}
return 0;
#endif
}
/* symlink */
int
tar_extract_symlink(TAR *t, char *realname)
{
char *filename;
char buf[T_BLOCKSIZE];
char *pathname = 0;
#ifndef _WIN32
if (!TH_ISSYM(t))
{
errno = EINVAL;
return -1;
}
#endif
if (realname)
{
filename = realname;
}
else
{
pathname = th_get_pathname(t);
filename = pathname;
}
/* Make a copy of the string because dirname and mkdirhier may modify the
* string */
strncpy(buf, filename, sizeof(buf)-1);
buf[sizeof(buf)-1] = 0;
if (mkdirhier(dirname(buf)) == -1)
{
if (pathname)
{
free(pathname);
}
return -1;
}
if (unlink(filename) == -1 && errno != ENOENT)
{
if (pathname)
{
free(pathname);
}
return -1;
}
#ifdef DEBUG
printf(" ==> extracting: %s (symlink to %s)\n",
filename, th_get_linkname(t));
#endif
#ifndef WIN32
if (symlink(th_get_linkname(t), filename) == -1)
#endif
{
#ifdef DEBUG
perror("symlink()");
#endif
if (pathname)
{
free(pathname);
}
return -1;
}
#ifndef WIN32
if (pathname)
{
free(pathname);
}
return 0;
#endif
}
/* character device */
int
tar_extract_chardev(TAR *t, char *realname)
{
mode_t mode;
unsigned long devmaj, devmin;
char *filename;
char buf[T_BLOCKSIZE];
char *pathname = 0;
#ifndef _WIN32
if (!TH_ISCHR(t))
{
errno = EINVAL;
return -1;
}
#endif
if (realname)
{
filename = realname;
}
else
{
pathname = th_get_pathname(t);
filename = pathname;
}
mode = th_get_mode(t);
devmaj = th_get_devmajor(t);
devmin = th_get_devminor(t);
/* Make a copy of the string because dirname and mkdirhier may modify the
* string */
strncpy(buf, filename, sizeof(buf)-1);
buf[sizeof(buf)-1] = 0;
if (mkdirhier(dirname(buf)) == -1)
{
if (pathname)
{
free(pathname);
}
return -1;
}
#ifdef DEBUG
printf(" ==> extracting: %s (character device %ld,%ld)\n",
filename, devmaj, devmin);
#endif
#ifndef WIN32
if (mknod(filename, mode | S_IFCHR,
compat_makedev(devmaj, devmin)) == -1)
#else
(void)devmin;
(void)devmaj;
(void)mode;
#endif
{
#ifdef DEBUG
perror("mknod()");
#endif
if (pathname)
{
free(pathname);
}
return -1;
}
#ifndef WIN32
if (pathname)
{
free(pathname);
}
return 0;
#endif
}
/* block device */
int
tar_extract_blockdev(TAR *t, char *realname)
{
mode_t mode;
unsigned long devmaj, devmin;
char *filename;
char buf[T_BLOCKSIZE];
char *pathname = 0;
if (!TH_ISBLK(t))
{
errno = EINVAL;
return -1;
}
if (realname)
{
filename = realname;
}
else
{
pathname = th_get_pathname(t);
filename = pathname;
}
mode = th_get_mode(t);
devmaj = th_get_devmajor(t);
devmin = th_get_devminor(t);
/* Make a copy of the string because dirname and mkdirhier may modify the
* string */
strncpy(buf, filename, sizeof(buf)-1);
buf[sizeof(buf)-1] = 0;
if (mkdirhier(dirname(buf)) == -1)
{
if (pathname)
{
free(pathname);
}
return -1;
}
#ifdef DEBUG
printf(" ==> extracting: %s (block device %ld,%ld)\n",
filename, devmaj, devmin);
#endif
#ifndef WIN32
if (mknod(filename, mode | S_IFBLK,
compat_makedev(devmaj, devmin)) == -1)
#else
(void)devmin;
(void)devmaj;
(void)mode;
#endif
{
#ifdef DEBUG
perror("mknod()");
#endif
if (pathname)
{
free(pathname);
}
return -1;
}
#ifndef WIN32
if (pathname)
{
free(pathname);
}
return 0;
#endif
}
/* directory */
int
tar_extract_dir(TAR *t, char *realname)
{
mode_t mode;
char *filename;
char buf[T_BLOCKSIZE];
char *pathname = 0;
size_t len = 0;
if (!TH_ISDIR(t))
{
errno = EINVAL;
return -1;
}
if (realname)
{
filename = realname;
}
else
{
pathname = th_get_pathname(t);
filename = pathname;
}
mode = th_get_mode(t);
/* Make a copy of the string because dirname and mkdirhier may modify the
* string */
strncpy(buf, filename, sizeof(buf)-1);
buf[sizeof(buf)-1] = 0;
if (mkdirhier(dirname(buf)) == -1)
{
if (pathname)
{
free(pathname);
}
return -1;
}
/* Strip trailing '/'...it confuses some Unixes (and BeOS)... */
strncpy(buf, filename, sizeof(buf)-1);
buf[sizeof(buf)-1] = 0;
len = strlen(buf);
if ((len > 0) && (buf[len-1] == '/'))
{
buf[len-1] = '\0';
}
#ifdef DEBUG
printf(" ==> extracting: %s (mode %04o, directory)\n", filename,
mode);
#endif
#ifdef WIN32
if (mkdir(buf) == -1)
#else
if (mkdir(buf, mode & 07777) == -1)
#endif
{
#ifdef __BORLANDC__
/* There is a bug in the Borland Run time library which makes MKDIR
return EACCES when it should return EEXIST
if it is some other error besides directory exists
then return false */
if ( errno == EACCES)
{
errno = EEXIST;
}
#endif
if (errno == EEXIST)
{
if (chmod(filename, mode & 07777) == -1)
{
#ifdef DEBUG
perror("chmod()");
#endif
if (pathname)
{
free(pathname);
}
return -1;
}
else
{
#ifdef DEBUG
puts(" *** using existing directory");
#endif
if (pathname)
{
free(pathname);
}
return 1;
}
}
else
{
#ifdef DEBUG
perror("mkdir()");
#endif
if (pathname)
{
free(pathname);
}
return -1;
}
}
if (pathname)
{
free(pathname);
}
return 0;
}
/* FIFO */
int
tar_extract_fifo(TAR *t, char *realname)
{
mode_t mode;
char *filename;
char buf[T_BLOCKSIZE];
char *pathname = 0;
if (!TH_ISFIFO(t))
{
errno = EINVAL;
return -1;
}
if (realname)
{
filename = realname;
}
else
{
pathname = th_get_pathname(t);
filename = pathname;
}
mode = th_get_mode(t);
/* Make a copy of the string because dirname and mkdirhier may modify the
* string */
strncpy(buf, filename, sizeof(buf)-1);
buf[sizeof(buf)-1] = 0;
if (mkdirhier(dirname(buf)) == -1)
{
if (pathname)
{
free(pathname);
}
return -1;
}
#ifdef DEBUG
printf(" ==> extracting: %s (fifo)\n", filename);
#endif
#ifndef WIN32
if (mkfifo(filename, mode & 07777) == -1)
#else
(void)mode;
#endif
{
#ifdef DEBUG
perror("mkfifo()");
#endif
if (pathname)
{
free(pathname);
}
return -1;
}
#ifndef WIN32
if (pathname)
{
free(pathname);
}
return 0;
#endif
}