tar: handle tarfiles with (broken) checksums a-la Sun.

This commit is contained in:
Denis Vlasenko 2007-03-03 20:06:59 +00:00
parent 19c238bc90
commit dcbd51dd28
2 changed files with 16 additions and 6 deletions

View File

@ -69,7 +69,7 @@ char get_header_tar(archive_handle_t *archive_handle)
char padding[12]; /* 500-512 */
} tar;
char *cp;
int sum, i;
int i, sum_u, sum_s, sum;
int parse_names;
if (sizeof(tar) != 512)
@ -110,16 +110,23 @@ char get_header_tar(archive_handle_t *archive_handle)
#endif
bb_error_msg_and_die("invalid tar magic");
}
/* Do checksum on headers */
sum = ' ' * sizeof(tar.chksum);
/* Do checksum on headers.
* POSIX says that checksum is done on unsigned bytes, but
* Sun and HP-UX fucked it up... more details in
* GNU tar source. */
sum_s = sum_u = ' ' * sizeof(tar.chksum);
for (i = 0; i < 148 ; i++) {
sum += ((char*)&tar)[i];
sum_u += ((unsigned char*)&tar)[i];
sum_s += ((signed char*)&tar)[i];
}
for (i = 156; i < 512 ; i++) {
sum += ((char*)&tar)[i];
sum_u += ((unsigned char*)&tar)[i];
sum_s += ((signed char*)&tar)[i];
}
/* This field does not need special treatment (getOctal) */
if (sum != xstrtoul(tar.chksum, 8)) {
sum = xstrtoul(tar.chksum, 8);
if (sum_u != sum && sum_s != sum) {
bb_error_msg_and_die("invalid tar header checksum");
}

View File

@ -173,6 +173,9 @@ static void putOctal(char *cp, int len, off_t value)
static void chksum_and_xwrite(int fd, struct TarHeader* hp)
{
/* POSIX says that checksum is done on unsigned bytes
* (Sun and HP-UX fucked it up... more details in
* GNU tar source) */
const unsigned char *cp;
int chksum, size;