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rename archival/libunarchive -> archival/libarchive; move bz/ into it

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Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko
2010-11-03 02:38:31 +01:00
parent 5e9934028a
commit 833d4e7f84
74 changed files with 57 additions and 57 deletions
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461
archival/libarchive/get_header_tar.c Normal file
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/* vi: set sw=4 ts=4: */
/* Licensed under GPLv2 or later, see file LICENSE in this source tree.
*
* 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 "archive.h"
typedef uint32_t aliased_uint32_t FIX_ALIASING;
typedef off_t aliased_off_t FIX_ALIASING;
/* NB: _DESTROYS_ str[len] character! */
static unsigned long long getOctal(char *str, int len)
{
unsigned long long v;
char *end;
/* NB: leading spaces are allowed. Using strtoull to handle that.
* The downside is that we accept e.g. "-123" too :(
*/
str[len] = '\0';
v = strtoull(str, &end, 8);
/* std: "Each numeric field is terminated by one or more
* <space> or NUL characters". We must support ' '! */
if (*end != '\0' && *end != ' ') {
int8_t first = str[0];
if (!(first & 0x80))
bb_error_msg_and_die("corrupted octal value in tar header");
/*
* GNU tar uses "base-256 encoding" for very large numbers.
* Encoding is binary, with highest bit always set as a marker
* and sign in next-highest bit:
* 80 00 .. 00 - zero
* bf ff .. ff - largest positive number
* ff ff .. ff - minus 1
* c0 00 .. 00 - smallest negative number
*
* Example of tar file with 8914993153 (0x213600001) byte file.
* Field starts at offset 7c:
* 00070 30 30 30 00 30 30 30 30 30 30 30 00 80 00 00 00 |000.0000000.....|
* 00080 00 00 00 02 13 60 00 01 31 31 31 32 30 33 33 36 |.....`..11120336|
*
* NB: tarballs with NEGATIVE unix times encoded that way were seen!
*/
v = first;
/* Sign-extend using 6th bit: */
v <<= sizeof(unsigned long long)*8 - 7;
v = (long long)v >> (sizeof(unsigned long long)*8 - 7);
while (--len != 0)
v = (v << 8) + (unsigned char) *str++;
}
return v;
}
#define GET_OCTAL(a) getOctal((a), sizeof(a))
#if ENABLE_FEATURE_TAR_SELINUX
/* Scan a PAX header for SELinux contexts, via "RHT.security.selinux" keyword.
* This is what Red Hat's patched version of tar uses.
*/
# define SELINUX_CONTEXT_KEYWORD "RHT.security.selinux"
static char *get_selinux_sctx_from_pax_hdr(archive_handle_t *archive_handle, unsigned sz)
{
char *buf, *p;
char *result;
p = buf = xmalloc(sz + 1);
/* prevent bb_strtou from running off the buffer */
buf[sz] = '\0';
xread(archive_handle->src_fd, buf, sz);
archive_handle->offset += sz;
result = NULL;
while (sz != 0) {
char *end, *value;
unsigned len;
/* Every record has this format: "LEN NAME=VALUE\n" */
len = bb_strtou(p, &end, 10);
/* expect errno to be EINVAL, because the character
* following the digits should be a space
*/
p += len;
sz -= len;
if ((int)sz < 0
|| len == 0
|| errno != EINVAL
|| *end != ' '
) {
bb_error_msg("malformed extended header, skipped");
// More verbose version:
//bb_error_msg("malformed extended header at %"OFF_FMT"d, skipped",
// archive_handle->offset - (sz + len));
break;
}
/* overwrite the terminating newline with NUL
* (we do not bother to check that it *was* a newline)
*/
p[-1] = '\0';
/* Is it selinux security context? */
value = end + 1;
if (strncmp(value, SELINUX_CONTEXT_KEYWORD"=", sizeof(SELINUX_CONTEXT_KEYWORD"=") - 1) == 0) {
value += sizeof(SELINUX_CONTEXT_KEYWORD"=") - 1;
result = xstrdup(value);
break;
}
}
free(buf);
return result;
}
#endif
char FAST_FUNC get_header_tar(archive_handle_t *archive_handle)
{
file_header_t *file_header = archive_handle->file_header;
struct tar_header_t tar;
char *cp;
int i, sum_u, sum;
#if ENABLE_FEATURE_TAR_OLDSUN_COMPATIBILITY
int sum_s;
#endif
int parse_names;
/* Our "private data" */
#if ENABLE_FEATURE_TAR_GNU_EXTENSIONS
# define p_longname (archive_handle->tar__longname)
# define p_linkname (archive_handle->tar__linkname)
#else
# define p_longname 0
# define p_linkname 0
#endif
#if ENABLE_FEATURE_TAR_GNU_EXTENSIONS || ENABLE_FEATURE_TAR_SELINUX
again:
#endif
/* Align header */
data_align(archive_handle, 512);
again_after_align:
#if ENABLE_DESKTOP || ENABLE_FEATURE_TAR_AUTODETECT
/* to prevent misdetection of bz2 sig */
*(aliased_uint32_t*)&tar = 0;
i = full_read(archive_handle->src_fd, &tar, 512);
/* If GNU tar sees EOF in above read, it says:
* "tar: A lone zero block at N", where N = kilobyte
* where EOF was met (not EOF block, actual EOF!),
* and exits with EXIT_SUCCESS.
* We will mimic exit(EXIT_SUCCESS), although we will not mimic
* the message and we don't check whether we indeed
* saw zero block directly before this. */
if (i == 0) {
xfunc_error_retval = 0;
short_read:
bb_error_msg_and_die("short read");
}
if (i != 512) {
IF_FEATURE_TAR_AUTODETECT(goto autodetect;)
goto short_read;
}
#else
i = 512;
xread(archive_handle->src_fd, &tar, i);
#endif
archive_handle->offset += i;
/* If there is no filename its an empty header */
if (tar.name[0] == 0 && tar.prefix[0] == 0) {
if (archive_handle->tar__end) {
/* 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, 512) == 512)
continue;
return EXIT_FAILURE;
}
archive_handle->tar__end = 1;
return EXIT_SUCCESS;
}
archive_handle->tar__end = 0;
/* Check header has valid magic, "ustar" is for the proper tar,
* five NULs are for the old tar format */
if (strncmp(tar.magic, "ustar", 5) != 0
&& (!ENABLE_FEATURE_TAR_OLDGNU_COMPATIBILITY
|| memcmp(tar.magic, "\0\0\0\0", 5) != 0)
) {
#if ENABLE_FEATURE_TAR_AUTODETECT
char FAST_FUNC (*get_header_ptr)(archive_handle_t *);
uint16_t magic2;
autodetect:
magic2 = *(uint16_t*)tar.name;
/* tar gz/bz autodetect: check for gz/bz2 magic.
* If we see the magic, and it is the very first block,
* we can switch to get_header_tar_gz/bz2/lzma().
* Needs seekable fd. I wish recv(MSG_PEEK) works
* on any fd... */
# if ENABLE_FEATURE_SEAMLESS_GZ
if (magic2 == GZIP_MAGIC) {
get_header_ptr = get_header_tar_gz;
} else
# endif
# if ENABLE_FEATURE_SEAMLESS_BZ2
if (magic2 == BZIP2_MAGIC
&& tar.name[2] == 'h' && isdigit(tar.name[3])
) { /* bzip2 */
get_header_ptr = get_header_tar_bz2;
} else
# endif
# if ENABLE_FEATURE_SEAMLESS_XZ
//TODO: if (magic2 == XZ_MAGIC1)...
//else
# endif
goto err;
/* Two different causes for lseek() != 0:
* unseekable fd (would like to support that too, but...),
* or not first block (false positive, it's not .gz/.bz2!) */
if (lseek(archive_handle->src_fd, -i, SEEK_CUR) != 0)
goto err;
while (get_header_ptr(archive_handle) == EXIT_SUCCESS)
continue;
return EXIT_FAILURE;
err:
#endif /* FEATURE_TAR_AUTODETECT */
bb_error_msg_and_die("invalid tar magic");
}
/* Do checksum on headers.
* POSIX says that checksum is done on unsigned bytes, but
* Sun and HP-UX gets it wrong... more details in
* GNU tar source. */
#if ENABLE_FEATURE_TAR_OLDSUN_COMPATIBILITY
sum_s = ' ' * sizeof(tar.chksum);
#endif
sum_u = ' ' * sizeof(tar.chksum);
for (i = 0; i < 148; i++) {
sum_u += ((unsigned char*)&tar)[i];
#if ENABLE_FEATURE_TAR_OLDSUN_COMPATIBILITY
sum_s += ((signed char*)&tar)[i];
#endif
}
for (i = 156; i < 512; i++) {
sum_u += ((unsigned char*)&tar)[i];
#if ENABLE_FEATURE_TAR_OLDSUN_COMPATIBILITY
sum_s += ((signed char*)&tar)[i];
#endif
}
/* This field does not need special treatment (getOctal) */
{
char *endp; /* gcc likes temp var for &endp */
sum = strtoul(tar.chksum, &endp, 8);
if ((*endp != '\0' && *endp != ' ')
|| (sum_u != sum IF_FEATURE_TAR_OLDSUN_COMPATIBILITY(&& sum_s != sum))
) {
bb_error_msg_and_die("invalid tar header checksum");
}
}
/* don't use xstrtoul, tar.chksum may have leading spaces */
sum = strtoul(tar.chksum, NULL, 8);
if (sum_u != sum IF_FEATURE_TAR_OLDSUN_COMPATIBILITY(&& sum_s != sum)) {
bb_error_msg_and_die("invalid tar header checksum");
}
/* 0 is reserved for high perf file, treat as normal file */
if (!tar.typeflag) tar.typeflag = '0';
parse_names = (tar.typeflag >= '0' && tar.typeflag <= '7');
/* getOctal trashes subsequent field, therefore we call it
* on fields in reverse order */
if (tar.devmajor[0]) {
char t = tar.prefix[0];
/* we trash prefix[0] here, but we DO need it later! */
unsigned minor = GET_OCTAL(tar.devminor);
unsigned major = GET_OCTAL(tar.devmajor);
file_header->device = makedev(major, minor);
tar.prefix[0] = t;
}
file_header->link_target = NULL;
if (!p_linkname && parse_names && tar.linkname[0]) {
file_header->link_target = xstrndup(tar.linkname, sizeof(tar.linkname));
/* FIXME: what if we have non-link object with link_target? */
/* Will link_target be free()ed? */
}
#if ENABLE_FEATURE_TAR_UNAME_GNAME
file_header->tar__uname = tar.uname[0] ? xstrndup(tar.uname, sizeof(tar.uname)) : NULL;
file_header->tar__gname = tar.gname[0] ? xstrndup(tar.gname, sizeof(tar.gname)) : NULL;
#endif
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);
/* Set bits 0-11 of the files mode */
file_header->mode = 07777 & GET_OCTAL(tar.mode);
file_header->name = NULL;
if (!p_longname && parse_names) {
/* we trash mode[0] here, it's ok */
//tar.name[sizeof(tar.name)] = '\0'; - gcc 4.3.0 would complain
tar.mode[0] = '\0';
if (tar.prefix[0]) {
/* and padding[0] */
//tar.prefix[sizeof(tar.prefix)] = '\0'; - gcc 4.3.0 would complain
tar.padding[0] = '\0';
file_header->name = concat_path_file(tar.prefix, tar.name);
} else
file_header->name = xstrdup(tar.name);
}
/* Set bits 12-15 of the files mode */
/* (typeflag was not trashed because chksum does not use getOctal) */
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;
break;
case '7':
/* case 0: */
case '0':
#if ENABLE_FEATURE_TAR_OLDGNU_COMPATIBILITY
if (last_char_is(file_header->name, '/')) {
goto set_dir;
}
#endif
file_header->mode |= S_IFREG;
break;
case '2':
file_header->mode |= S_IFLNK;
/* have seen tarballs with size field containing
* the size of the link target's name */
size0:
file_header->size = 0;
break;
case '3':
file_header->mode |= S_IFCHR;
goto size0; /* paranoia */
case '4':
file_header->mode |= S_IFBLK;
goto size0;
case '5':
IF_FEATURE_TAR_OLDGNU_COMPATIBILITY(set_dir:)
file_header->mode |= S_IFDIR;
goto size0;
case '6':
file_header->mode |= S_IFIFO;
goto size0;
#if ENABLE_FEATURE_TAR_GNU_EXTENSIONS
case 'L':
/* free: paranoia: tar with several consecutive longnames */
free(p_longname);
/* For paranoia reasons we allocate extra NUL char */
p_longname = xzalloc(file_header->size + 1);
/* We read ASCIZ string, including NUL */
xread(archive_handle->src_fd, p_longname, file_header->size);
archive_handle->offset += file_header->size;
/* return get_header_tar(archive_handle); */
/* gcc 4.1.1 didn't optimize it into jump */
/* so we will do it ourself, this also saves stack */
goto again;
case 'K':
free(p_linkname);
p_linkname = xzalloc(file_header->size + 1);
xread(archive_handle->src_fd, p_linkname, file_header->size);
archive_handle->offset += file_header->size;
/* return get_header_tar(archive_handle); */
goto again;
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
#if !ENABLE_FEATURE_TAR_SELINUX
case 'g': /* pax global header */
case 'x': /* pax extended header */
#else
skip_ext_hdr:
#endif
{
off_t sz;
bb_error_msg("warning: skipping header '%c'", tar.typeflag);
sz = (file_header->size + 511) & ~(off_t)511;
archive_handle->offset += sz;
sz >>= 9; /* sz /= 512 but w/o contortions for signed div */
while (sz--)
xread(archive_handle->src_fd, &tar, 512);
/* return get_header_tar(archive_handle); */
goto again_after_align;
}
#if ENABLE_FEATURE_TAR_SELINUX
case 'g': /* pax global header */
case 'x': { /* pax extended header */
char **pp;
if ((uoff_t)file_header->size > 0xfffff) /* paranoia */
goto skip_ext_hdr;
pp = (tar.typeflag == 'g') ? &archive_handle->tar__global_sctx : &archive_handle->tar__next_file_sctx;
free(*pp);
*pp = get_selinux_sctx_from_pax_hdr(archive_handle, file_header->size);
goto again;
}
#endif
default:
bb_error_msg_and_die("unknown typeflag: 0x%x", tar.typeflag);
}
#if ENABLE_FEATURE_TAR_GNU_EXTENSIONS
if (p_longname) {
file_header->name = p_longname;
p_longname = NULL;
}
if (p_linkname) {
file_header->link_target = p_linkname;
p_linkname = NULL;
}
#endif
if (strncmp(file_header->name, "/../"+1, 3) == 0
|| strstr(file_header->name, "/../")
) {
bb_error_msg_and_die("name with '..' encountered: '%s'",
file_header->name);
}
/* Strip trailing '/' in directories */
/* Must be done after mode is set as '/' is used to check if it's a directory */
cp = last_char_is(file_header->name, '/');
if (archive_handle->filter(archive_handle) == EXIT_SUCCESS) {
archive_handle->action_header(/*archive_handle->*/ file_header);
/* Note that we kill the '/' only after action_header() */
/* (like GNU tar 1.15.1: verbose mode outputs "dir/dir/") */
if (cp)
*cp = '\0';
archive_handle->action_data(archive_handle);
if (archive_handle->accept || archive_handle->reject)
llist_add_to(&archive_handle->passed, file_header->name);
else /* Caller isn't interested in list of unpacked files */
free(file_header->name);
} else {
data_skip(archive_handle);
free(file_header->name);
}
archive_handle->offset += file_header->size;
free(file_header->link_target);
/* Do not free(file_header->name)!
* It might be inserted in archive_handle->passed - see above */
#if ENABLE_FEATURE_TAR_UNAME_GNAME
free(file_header->tar__uname);
free(file_header->tar__gname);
#endif
return EXIT_SUCCESS;
}