busybox/archival/libunarchive/get_header_tar.c
Rob Landley d921b2ecc0 Remove bb_ prefixes from xfuncs.c (and a few other places), consolidate
things like xasprintf() into xfuncs.c, remove xprint_file_by_name() (it only
had one user), clean up lots of #includes...  General cleanup pass.  What I've
been doing for the last couple days.

And it conflicts!  I've removed httpd.c from this checkin due to somebody else
touching that file.  It builds for me.  I have to catch a bus.  (Now you know
why I'm looking forward to Mercurial.)
2006-08-03 15:41:12 +00:00

209 lines
5.7 KiB
C

/* vi: set sw=4 ts=4: */
/* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
*
* FIXME:
* In privileged mode if uname and gname map to a uid and gid then use the
* mapped value instead of the uid/gid values in tar header
*
* References:
* GNU tar and star man pages,
* Opengroup's ustar interchange format,
* http://www.opengroup.org/onlinepubs/007904975/utilities/pax.html
*/
#include "libbb.h"
#include "unarchive.h"
#ifdef CONFIG_FEATURE_TAR_GNU_EXTENSIONS
static char *longname = NULL;
static char *linkname = NULL;
#endif
char get_header_tar(archive_handle_t *archive_handle)
{
file_header_t *file_header = archive_handle->file_header;
union {
/* ustar header, Posix 1003.1 */
unsigned char raw[512];
struct {
char name[100]; /* 0-99 */
char mode[8]; /* 100-107 */
char uid[8]; /* 108-115 */
char gid[8]; /* 116-123 */
char size[12]; /* 124-135 */
char mtime[12]; /* 136-147 */
char chksum[8]; /* 148-155 */
char typeflag; /* 156-156 */
char linkname[100]; /* 157-256 */
char magic[6]; /* 257-262 */
char version[2]; /* 263-264 */
char uname[32]; /* 265-296 */
char gname[32]; /* 297-328 */
char devmajor[8]; /* 329-336 */
char devminor[8]; /* 337-344 */
char prefix[155]; /* 345-499 */
char padding[12]; /* 500-512 */
} formatted;
} tar;
long sum = 0;
long i;
static int end = 0;
/* Align header */
data_align(archive_handle, 512);
xread(archive_handle->src_fd, tar.raw, 512);
archive_handle->offset += 512;
/* If there is no filename its an empty header */
if (tar.formatted.name[0] == 0) {
if (end) {
/* This is the second consecutive empty header! End of archive!
* Read until the end to empty the pipe from gz or bz2
*/
while (full_read(archive_handle->src_fd, tar.raw, 512) == 512);
return(EXIT_FAILURE);
}
end = 1;
return(EXIT_SUCCESS);
}
end = 0;
/* Check header has valid magic, "ustar" is for the proper tar
* 0's are for the old tar format
*/
if (strncmp(tar.formatted.magic, "ustar", 5) != 0) {
#ifdef CONFIG_FEATURE_TAR_OLDGNU_COMPATIBILITY
if (strncmp(tar.formatted.magic, "\0\0\0\0\0", 5) != 0)
#endif
bb_error_msg_and_die("Invalid tar magic");
}
/* Do checksum on headers */
for (i = 0; i < 148 ; i++) {
sum += tar.raw[i];
}
sum += ' ' * 8;
for (i = 156; i < 512 ; i++) {
sum += tar.raw[i];
}
if (sum != strtol(tar.formatted.chksum, NULL, 8)) {
bb_error_msg("Invalid tar header checksum");
return(EXIT_FAILURE);
}
#ifdef CONFIG_FEATURE_TAR_GNU_EXTENSIONS
if (longname) {
file_header->name = longname;
longname = NULL;
}
else if (linkname) {
file_header->name = linkname;
linkname = NULL;
} else
#endif
{
file_header->name = xstrndup(tar.formatted.name,100);
if (tar.formatted.prefix[0]) {
char *temp = file_header->name;
file_header->name = concat_path_file(tar.formatted.prefix, temp);
free(temp);
}
}
file_header->uid = strtol(tar.formatted.uid, NULL, 8);
file_header->gid = strtol(tar.formatted.gid, NULL, 8);
file_header->size = strtol(tar.formatted.size, NULL, 8);
file_header->mtime = strtol(tar.formatted.mtime, NULL, 8);
file_header->link_name = (tar.formatted.linkname[0] != '\0') ?
xstrdup(tar.formatted.linkname) : NULL;
file_header->device = makedev(strtol(tar.formatted.devmajor, NULL, 8),
strtol(tar.formatted.devminor, NULL, 8));
/* Set bits 0-11 of the files mode */
file_header->mode = 07777 & strtol(tar.formatted.mode, NULL, 8);
/* Set bits 12-15 of the files mode */
switch (tar.formatted.typeflag) {
/* busybox identifies hard links as being regular files with 0 size and a link name */
case '1':
file_header->mode |= S_IFREG;
break;
case '7':
/* Reserved for high performance files, treat as normal file */
case 0:
case '0':
#ifdef CONFIG_FEATURE_TAR_OLDGNU_COMPATIBILITY
if (last_char_is(file_header->name, '/')) {
file_header->mode |= S_IFDIR;
} else
#endif
file_header->mode |= S_IFREG;
break;
case '2':
file_header->mode |= S_IFLNK;
break;
case '3':
file_header->mode |= S_IFCHR;
break;
case '4':
file_header->mode |= S_IFBLK;
break;
case '5':
file_header->mode |= S_IFDIR;
break;
case '6':
file_header->mode |= S_IFIFO;
break;
#ifdef CONFIG_FEATURE_TAR_GNU_EXTENSIONS
case 'L': {
longname = xzalloc(file_header->size + 1);
xread(archive_handle->src_fd, longname, file_header->size);
archive_handle->offset += file_header->size;
return(get_header_tar(archive_handle));
}
case 'K': {
linkname = xzalloc(file_header->size + 1);
xread(archive_handle->src_fd, linkname, file_header->size);
archive_handle->offset += file_header->size;
file_header->name = linkname;
return(get_header_tar(archive_handle));
}
case 'D': /* GNU dump dir */
case 'M': /* Continuation of multi volume archive*/
case 'N': /* Old GNU for names > 100 characters */
case 'S': /* Sparse file */
case 'V': /* Volume header */
#endif
case 'g': /* pax global header */
case 'x': /* pax extended header */
bb_error_msg("Ignoring extension type %c", tar.formatted.typeflag);
break;
default:
bb_error_msg("Unknown typeflag: 0x%x", tar.formatted.typeflag);
}
{ /* Strip trailing '/' in directories */
/* Must be done after mode is set as '/' is used to check if its a directory */
char *tmp = last_char_is(file_header->name, '/');
if (tmp) {
*tmp = '\0';
}
}
if (archive_handle->filter(archive_handle) == EXIT_SUCCESS) {
archive_handle->action_header(archive_handle->file_header);
archive_handle->flags |= ARCHIVE_EXTRACT_QUIET;
archive_handle->action_data(archive_handle);
llist_add_to(&(archive_handle->passed), file_header->name);
} else {
data_skip(archive_handle);
}
archive_handle->offset += file_header->size;
free(file_header->link_name);
return(EXIT_SUCCESS);
}