tar:
* unpack: handle tar header fields which are not NUL terminated
* pack: handle 4+GB files correctly
* pack: refuse to store 101+ softlinks (was truncating link
target name)
* pack: mask mode with 07777
diff --git a/archival/libunarchive/get_header_tar.c b/archival/libunarchive/get_header_tar.c
index f78377e..b5cae9f 100644
--- a/archival/libunarchive/get_header_tar.c
+++ b/archival/libunarchive/get_header_tar.c
@@ -19,49 +19,69 @@
static char *linkname = NULL;
#endif
+/* NB: _DESTROYS_ str[len] character! */
+static unsigned long long getOctal(char *str, int len)
+{
+ unsigned long long v;
+ /* Actually, tar header allows leading spaces also.
+ * Oh well, we will be liberal and skip this...
+ * The only downside probably is that we allow "-123" too :)
+ if (*str < '0' || *str > '7')
+ bb_error_msg_and_die("corrupted octal value in tar header");
+ */
+ str[len] = '\0';
+ v = strtoull(str, &str, 8);
+ if (*str)
+ bb_error_msg_and_die("corrupted octal value in tar header");
+ return v;
+}
+
+void BUG_tar_header_size(void);
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;
+ file_header_t *file_header = archive_handle->file_header;
+ struct {
+ /* ustar header, Posix 1003.1 */
+ 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 */
+ } tar;
+ char *cp;
+ int sum, i;
+
+ if (sizeof(tar) != 512)
+ BUG_tar_header_size();
+
/* Align header */
data_align(archive_handle, 512);
- xread(archive_handle->src_fd, tar.raw, 512);
+ xread(archive_handle->src_fd, &tar, 512);
archive_handle->offset += 512;
/* If there is no filename its an empty header */
- if (tar.formatted.name[0] == 0) {
+ if (tar.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);
+ while (full_read(archive_handle->src_fd, &tar, 512) == 512)
+ /* repeat */;
return EXIT_FAILURE;
}
end = 1;
@@ -72,21 +92,22 @@
/* 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) {
+ if (strncmp(tar.magic, "ustar", 5) != 0) {
#ifdef CONFIG_FEATURE_TAR_OLDGNU_COMPATIBILITY
- if (memcmp(tar.formatted.magic, "\0\0\0\0", 5) != 0)
+ if (memcmp(tar.magic, "\0\0\0\0", 5) != 0)
#endif
bb_error_msg_and_die("invalid tar magic");
}
/* Do checksum on headers */
+ sum = ' ' * sizeof(tar.chksum);
for (i = 0; i < 148 ; i++) {
- sum += tar.raw[i];
+ sum += ((char*)&tar)[i];
}
- sum += ' ' * 8;
for (i = 156; i < 512 ; i++) {
- sum += tar.raw[i];
+ sum += ((char*)&tar)[i];
}
- if (sum != xstrtoul(tar.formatted.chksum, 8)) {
+ /* This field does not need special treatment (getOctal) */
+ if (sum != xstrtoul(tar.chksum, 8)) {
bb_error_msg_and_die("invalid tar header checksum");
}
@@ -101,30 +122,34 @@
} else
#endif
{
- file_header->name = xstrndup(tar.formatted.name, 100);
- if (tar.formatted.prefix[0]) {
+ file_header->name = xstrndup(tar.name, sizeof(tar.name));
+ if (tar.prefix[0]) {
char *temp = file_header->name;
- file_header->name = concat_path_file(tar.formatted.prefix, temp);
+ file_header->name = concat_path_file(tar.prefix, temp);
free(temp);
}
}
- file_header->uid = xstrtoul(tar.formatted.uid, 8);
- file_header->gid = xstrtoul(tar.formatted.gid, 8);
- file_header->size = XSTRTOUOFF(tar.formatted.size, 8);
- file_header->mtime = xstrtoul(tar.formatted.mtime, 8);
- file_header->link_name = tar.formatted.linkname[0] ?
- xstrdup(tar.formatted.linkname) : NULL;
- if (tar.formatted.devmajor[0]) {
- file_header->device = makedev(xstrtoul(tar.formatted.devmajor, 8),
- xstrtoul(tar.formatted.devminor, 8));
+ /* getOctal trashes subsequent field, therefore we call it
+ * on fields in reverse order */
+#define GET_OCTAL(a) getOctal((a), sizeof(a))
+ if (tar.devmajor[0]) {
+ unsigned minor = GET_OCTAL(tar.devminor);
+ unsigned major = GET_OCTAL(tar.devmajor);
+ file_header->device = makedev(major, minor);
}
-
+ file_header->mtime = GET_OCTAL(tar.mtime);
+ file_header->size = GET_OCTAL(tar.size);
+ file_header->gid = GET_OCTAL(tar.gid);
+ file_header->uid = GET_OCTAL(tar.uid);
+ file_header->link_name = !tar.linkname[0] ? NULL :
+ xstrndup(tar.linkname, sizeof(tar.linkname));
/* Set bits 0-11 of the files mode */
- file_header->mode = 07777 & xstrtoul(tar.formatted.mode, 8);
+ file_header->mode = 07777 & GET_OCTAL(tar.mode);
+#undef GET_OCTAL
/* Set bits 12-15 of the files mode */
- switch (tar.formatted.typeflag) {
+ switch (tar.typeflag) {
/* busybox identifies hard links as being regular files with 0 size and a link name */
case '1':
file_header->mode |= S_IFREG;
@@ -138,7 +163,7 @@
file_header->mode |= S_IFDIR;
} else
#endif
- file_header->mode |= S_IFREG;
+ file_header->mode |= S_IFREG;
break;
case '2':
file_header->mode |= S_IFLNK;
@@ -156,41 +181,35 @@
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 '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 '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);
+ bb_error_msg("ignoring extension type %c", tar.typeflag);
break;
default:
- bb_error_msg("unknown typeflag: 0x%x", tar.formatted.typeflag);
+ bb_error_msg("unknown typeflag: 0x%x", tar.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';
- }
- }
+
+ /* Strip trailing '/' in directories */
+ /* Must be done after mode is set as '/' is used to check if its a directory */
+ cp = last_char_is(file_header->name, '/');
+ if (cp) *cp = '\0';
if (archive_handle->filter(archive_handle) == EXIT_SUCCESS) {
archive_handle->action_header(archive_handle->file_header);