freebsd-dev/lib/libarchive/archive_read_support_format_cpio.c
Tim Kientzle a46c33df05 Fine-tune the format detection for CPIO and ISO9660 sub-types.
This has no impact on the actual operation, it just fixes some
inaccuracies in the format code and description reported back to the caller.
2005-11-08 07:41:03 +00:00

605 lines
18 KiB
C

/*-
* Copyright (c) 2003-2004 Tim Kientzle
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer
* in this position and unchanged.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "archive_platform.h"
__FBSDID("$FreeBSD$");
#include <sys/stat.h>
#include <errno.h>
/* #include <stdint.h> */ /* See archive_platform.h */
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "archive.h"
#include "archive_entry.h"
#include "archive_private.h"
struct cpio_bin_header {
unsigned char c_magic[2];
unsigned char c_dev[2];
unsigned char c_ino[2];
unsigned char c_mode[2];
unsigned char c_uid[2];
unsigned char c_gid[2];
unsigned char c_nlink[2];
unsigned char c_rdev[2];
unsigned char c_mtime[4];
unsigned char c_namesize[2];
unsigned char c_filesize[4];
};
struct cpio_odc_header {
char c_magic[6];
char c_dev[6];
char c_ino[6];
char c_mode[6];
char c_uid[6];
char c_gid[6];
char c_nlink[6];
char c_rdev[6];
char c_mtime[11];
char c_namesize[6];
char c_filesize[11];
};
struct cpio_newc_header {
char c_magic[6];
char c_ino[8];
char c_mode[8];
char c_uid[8];
char c_gid[8];
char c_nlink[8];
char c_mtime[8];
char c_filesize[8];
char c_devmajor[8];
char c_devminor[8];
char c_rdevmajor[8];
char c_rdevminor[8];
char c_namesize[8];
char c_crc[8];
};
struct links_entry {
struct links_entry *next;
struct links_entry *previous;
int links;
dev_t dev;
ino_t ino;
char *name;
};
#define CPIO_MAGIC 0x13141516
struct cpio {
int magic;
int (*read_header)(struct archive *, struct cpio *,
struct stat *, size_t *, size_t *);
struct links_entry *links_head;
struct archive_string entry_name;
struct archive_string entry_linkname;
off_t entry_bytes_remaining;
off_t entry_offset;
off_t entry_padding;
};
static int64_t atol16(const char *, unsigned);
static int64_t atol8(const char *, unsigned);
static int archive_read_format_cpio_bid(struct archive *);
static int archive_read_format_cpio_cleanup(struct archive *);
static int archive_read_format_cpio_read_data(struct archive *,
const void **, size_t *, off_t *);
static int archive_read_format_cpio_read_header(struct archive *,
struct archive_entry *);
static int be4(const unsigned char *);
static int header_bin_be(struct archive *, struct cpio *, struct stat *,
size_t *, size_t *);
static int header_bin_le(struct archive *, struct cpio *, struct stat *,
size_t *, size_t *);
static int header_newc(struct archive *, struct cpio *, struct stat *,
size_t *, size_t *);
static int header_odc(struct archive *, struct cpio *, struct stat *,
size_t *, size_t *);
static int le4(const unsigned char *);
static void record_hardlink(struct cpio *cpio, struct archive_entry *entry,
const struct stat *st);
int
archive_read_support_format_cpio(struct archive *a)
{
struct cpio *cpio;
int r;
cpio = malloc(sizeof(*cpio));
if (cpio == NULL) {
archive_set_error(a, ENOMEM, "Can't allocate cpio data");
return (ARCHIVE_FATAL);
}
memset(cpio, 0, sizeof(*cpio));
cpio->magic = CPIO_MAGIC;
r = __archive_read_register_format(a,
cpio,
archive_read_format_cpio_bid,
archive_read_format_cpio_read_header,
archive_read_format_cpio_read_data,
NULL,
archive_read_format_cpio_cleanup);
if (r != ARCHIVE_OK)
free(cpio);
return (ARCHIVE_OK);
}
static int
archive_read_format_cpio_bid(struct archive *a)
{
int bid, bytes_read;
const void *h;
const unsigned char *p;
struct cpio *cpio;
cpio = *(a->pformat_data);
bid = 0;
bytes_read = (a->compression_read_ahead)(a, &h, 6);
/* Convert error code into error return. */
if (bytes_read < 0)
return ((int)bytes_read);
if (bytes_read < 6)
return (-1);
p = h;
if (memcmp(p, "070707", 6) == 0) {
/* ASCII cpio archive (odc, POSIX.1) */
cpio->read_header = header_odc;
bid += 48;
/*
* XXX TODO: More verification; Could check that only octal
* digits appear in appropriate header locations. XXX
*/
} else if (memcmp(p, "070701", 6) == 0) {
/* ASCII cpio archive (SVR4 without CRC) */
cpio->read_header = header_newc;
bid += 48;
/*
* XXX TODO: More verification; Could check that only hex
* digits appear in appropriate header locations. XXX
*/
} else if (memcmp(p, "070702", 6) == 0) {
/* ASCII cpio archive (SVR4 with CRC) */
/* XXX TODO: Flag that we should check the CRC. XXX */
cpio->read_header = header_newc;
bid += 48;
/*
* XXX TODO: More verification; Could check that only hex
* digits appear in appropriate header locations. XXX
*/
} else if (p[0] * 256 + p[1] == 070707) {
/* big-endian binary cpio archives */
cpio->read_header = header_bin_be;
bid += 16;
/* Is more verification possible here? */
} else if (p[0] + p[1] * 256 == 070707) {
/* little-endian binary cpio archives */
cpio->read_header = header_bin_le;
bid += 16;
/* Is more verification possible here? */
} else
return (ARCHIVE_WARN);
return (bid);
}
static int
archive_read_format_cpio_read_header(struct archive *a,
struct archive_entry *entry)
{
struct stat st;
struct cpio *cpio;
size_t bytes;
const void *h;
size_t namelength;
size_t name_pad;
int r;
memset(&st, 0, sizeof(st));
cpio = *(a->pformat_data);
r = (cpio->read_header(a, cpio, &st, &namelength, &name_pad));
if (r != ARCHIVE_OK)
return (r);
/* Assign all of the 'stat' fields at once. */
archive_entry_copy_stat(entry, &st);
/* Read name from buffer. */
bytes = (a->compression_read_ahead)(a, &h, namelength + name_pad);
if (bytes < namelength + name_pad)
return (ARCHIVE_FATAL);
(a->compression_read_consume)(a, namelength + name_pad);
archive_strncpy(&cpio->entry_name, h, namelength);
archive_entry_set_pathname(entry, cpio->entry_name.s);
cpio->entry_offset = 0;
/* If this is a symlink, read the link contents. */
if (S_ISLNK(st.st_mode)) {
bytes = (a->compression_read_ahead)(a, &h,
cpio->entry_bytes_remaining);
if ((off_t)bytes < cpio->entry_bytes_remaining)
return (ARCHIVE_FATAL);
(a->compression_read_consume)(a, cpio->entry_bytes_remaining);
archive_strncpy(&cpio->entry_linkname, h,
cpio->entry_bytes_remaining);
archive_entry_set_symlink(entry, cpio->entry_linkname.s);
cpio->entry_bytes_remaining = 0;
}
/* Compare name to "TRAILER!!!" to test for end-of-archive. */
if (namelength == 11 && strcmp(h,"TRAILER!!!")==0) {
/* TODO: Store file location of start of block. */
archive_set_error(a, 0, NULL);
return (ARCHIVE_EOF);
}
/* Detect and record hardlinks to previously-extracted entries. */
record_hardlink(cpio, entry, &st);
return (ARCHIVE_OK);
}
static int
archive_read_format_cpio_read_data(struct archive *a,
const void **buff, size_t *size, off_t *offset)
{
ssize_t bytes_read;
struct cpio *cpio;
cpio = *(a->pformat_data);
if (cpio->entry_bytes_remaining > 0) {
bytes_read = (a->compression_read_ahead)(a, buff, 1);
if (bytes_read <= 0)
return (ARCHIVE_FATAL);
if (bytes_read > cpio->entry_bytes_remaining)
bytes_read = cpio->entry_bytes_remaining;
*size = bytes_read;
*offset = cpio->entry_offset;
cpio->entry_offset += bytes_read;
cpio->entry_bytes_remaining -= bytes_read;
(a->compression_read_consume)(a, bytes_read);
return (ARCHIVE_OK);
} else {
while (cpio->entry_padding > 0) {
bytes_read = (a->compression_read_ahead)(a, buff, 1);
if (bytes_read <= 0)
return (ARCHIVE_FATAL);
if (bytes_read > cpio->entry_padding)
bytes_read = cpio->entry_padding;
(a->compression_read_consume)(a, bytes_read);
cpio->entry_padding -= bytes_read;
}
*buff = NULL;
*size = 0;
*offset = cpio->entry_offset;
return (ARCHIVE_EOF);
}
}
static int
header_newc(struct archive *a, struct cpio *cpio, struct stat *st,
size_t *namelength, size_t *name_pad)
{
const void *h;
const struct cpio_newc_header *header;
size_t bytes;
/* Read fixed-size portion of header. */
bytes = (a->compression_read_ahead)(a, &h, sizeof(struct cpio_newc_header));
if (bytes < sizeof(struct cpio_newc_header))
return (ARCHIVE_FATAL);
(a->compression_read_consume)(a, sizeof(struct cpio_newc_header));
/* Parse out hex fields into struct stat. */
header = h;
if (memcmp(header->c_magic, "070701", 6) == 0) {
a->archive_format = ARCHIVE_FORMAT_CPIO_SVR4_NOCRC;
a->archive_format_name = "ASCII cpio (SVR4 with no CRC)";
} else if (memcmp(header->c_magic, "070702", 6) == 0) {
a->archive_format = ARCHIVE_FORMAT_CPIO_SVR4_CRC;
a->archive_format_name = "ASCII cpio (SVR4 with CRC)";
} else {
/* TODO: Abort here? */
}
st->st_ino = atol16(header->c_ino, sizeof(header->c_ino));
st->st_mode = atol16(header->c_mode, sizeof(header->c_mode));
st->st_uid = atol16(header->c_uid, sizeof(header->c_uid));
st->st_gid = atol16(header->c_gid, sizeof(header->c_gid));
st->st_nlink = atol16(header->c_nlink, sizeof(header->c_nlink));
st->st_mtime = atol16(header->c_mtime, sizeof(header->c_mtime));
*namelength = atol16(header->c_namesize, sizeof(header->c_namesize));
/* Pad name to 2 more than a multiple of 4. */
*name_pad = (2 - *namelength) & 3;
/*
* Note: entry_bytes_remaining is at least 64 bits and
* therefore gauranteed to be big enough for a 33-bit file
* size. struct stat.st_size may only be 32 bits, so
* assigning there first could lose information.
*/
cpio->entry_bytes_remaining =
atol16(header->c_filesize, sizeof(header->c_filesize));
st->st_size = cpio->entry_bytes_remaining;
/* Pad file contents to a multiple of 4. */
cpio->entry_padding = 3 & -cpio->entry_bytes_remaining;
return (ARCHIVE_OK);
}
static int
header_odc(struct archive *a, struct cpio *cpio, struct stat *st,
size_t *namelength, size_t *name_pad)
{
const void *h;
const struct cpio_odc_header *header;
size_t bytes;
a->archive_format = ARCHIVE_FORMAT_CPIO_POSIX;
a->archive_format_name = "POSIX octet-oriented cpio";
/* Read fixed-size portion of header. */
bytes = (a->compression_read_ahead)(a, &h, sizeof(struct cpio_odc_header));
if (bytes < sizeof(struct cpio_odc_header))
return (ARCHIVE_FATAL);
(a->compression_read_consume)(a, sizeof(struct cpio_odc_header));
/* Parse out octal fields into struct stat. */
header = h;
st->st_dev = atol8(header->c_dev, sizeof(header->c_dev));
st->st_ino = atol8(header->c_ino, sizeof(header->c_ino));
st->st_mode = atol8(header->c_mode, sizeof(header->c_mode));
st->st_uid = atol8(header->c_uid, sizeof(header->c_uid));
st->st_gid = atol8(header->c_gid, sizeof(header->c_gid));
st->st_nlink = atol8(header->c_nlink, sizeof(header->c_nlink));
st->st_rdev = atol8(header->c_rdev, sizeof(header->c_rdev));
st->st_mtime = atol8(header->c_mtime, sizeof(header->c_mtime));
*namelength = atol8(header->c_namesize, sizeof(header->c_namesize));
*name_pad = 0; /* No padding of filename. */
/*
* Note: entry_bytes_remaining is at least 64 bits and
* therefore gauranteed to be big enough for a 33-bit file
* size. struct stat.st_size may only be 32 bits, so
* assigning there first could lose information.
*/
cpio->entry_bytes_remaining =
atol8(header->c_filesize, sizeof(header->c_filesize));
st->st_size = cpio->entry_bytes_remaining;
cpio->entry_padding = 0;
return (ARCHIVE_OK);
}
static int
header_bin_le(struct archive *a, struct cpio *cpio, struct stat *st,
size_t *namelength, size_t *name_pad)
{
const void *h;
const struct cpio_bin_header *header;
size_t bytes;
a->archive_format = ARCHIVE_FORMAT_CPIO_BIN_LE;
a->archive_format_name = "cpio (little-endian binary)";
/* Read fixed-size portion of header. */
bytes = (a->compression_read_ahead)(a, &h, sizeof(struct cpio_bin_header));
if (bytes < sizeof(struct cpio_bin_header))
return (ARCHIVE_FATAL);
(a->compression_read_consume)(a, sizeof(struct cpio_bin_header));
/* Parse out binary fields into struct stat. */
header = h;
st->st_dev = header->c_dev[0] + header->c_dev[1] * 256;
st->st_ino = header->c_ino[0] + header->c_ino[1] * 256;
st->st_mode = header->c_mode[0] + header->c_mode[1] * 256;
st->st_uid = header->c_uid[0] + header->c_uid[1] * 256;
st->st_gid = header->c_gid[0] + header->c_gid[1] * 256;
st->st_nlink = header->c_nlink[0] + header->c_nlink[1] * 256;
st->st_rdev = header->c_rdev[0] + header->c_rdev[1] * 256;
st->st_mtime = le4(header->c_mtime);
*namelength = header->c_namesize[0] + header->c_namesize[1] * 256;
*name_pad = *namelength & 1; /* Pad to even. */
cpio->entry_bytes_remaining = le4(header->c_filesize);
st->st_size = cpio->entry_bytes_remaining;
cpio->entry_padding = cpio->entry_bytes_remaining & 1; /* Pad to even. */
return (ARCHIVE_OK);
}
static int
header_bin_be(struct archive *a, struct cpio *cpio, struct stat *st,
size_t *namelength, size_t *name_pad)
{
const void *h;
const struct cpio_bin_header *header;
size_t bytes;
a->archive_format = ARCHIVE_FORMAT_CPIO_BIN_BE;
a->archive_format_name = "cpio (big-endian binary)";
/* Read fixed-size portion of header. */
bytes = (a->compression_read_ahead)(a, &h,
sizeof(struct cpio_bin_header));
if (bytes < sizeof(struct cpio_bin_header))
return (ARCHIVE_FATAL);
(a->compression_read_consume)(a, sizeof(struct cpio_bin_header));
/* Parse out binary fields into struct stat. */
header = h;
st->st_dev = header->c_dev[0] * 256 + header->c_dev[1];
st->st_ino = header->c_ino[0] * 256 + header->c_ino[1];
st->st_mode = header->c_mode[0] * 256 + header->c_mode[1];
st->st_uid = header->c_uid[0] * 256 + header->c_uid[1];
st->st_gid = header->c_gid[0] * 256 + header->c_gid[1];
st->st_nlink = header->c_nlink[0] * 256 + header->c_nlink[1];
st->st_rdev = header->c_rdev[0] * 256 + header->c_rdev[1];
st->st_mtime = be4(header->c_mtime);
*namelength = header->c_namesize[0] * 256 + header->c_namesize[1];
*name_pad = *namelength & 1; /* Pad to even. */
cpio->entry_bytes_remaining = be4(header->c_filesize);
st->st_size = cpio->entry_bytes_remaining;
cpio->entry_padding = cpio->entry_bytes_remaining & 1; /* Pad to even. */
return (ARCHIVE_OK);
}
static int
archive_read_format_cpio_cleanup(struct archive *a)
{
struct cpio *cpio;
cpio = *(a->pformat_data);
/* Free inode->name map */
while (cpio->links_head != NULL) {
struct links_entry *lp = cpio->links_head->next;
if (cpio->links_head->name)
free(cpio->links_head->name);
free(cpio->links_head);
cpio->links_head = lp;
}
free(cpio);
*(a->pformat_data) = NULL;
return (ARCHIVE_OK);
}
static int
le4(const unsigned char *p)
{
return ((p[0]<<16) + (p[1]<<24) + (p[2]<<0) + (p[3]<<8));
}
static int
be4(const unsigned char *p)
{
return (p[0] + (p[1]<<8) + (p[2]<<16) + (p[3]<<24));
}
/*
* Note that this implementation does not (and should not!) obey
* locale settings; you cannot simply substitute strtol here, since
* it does obey locale.
*/
static int64_t
atol8(const char *p, unsigned char_cnt)
{
int64_t l;
int digit;
l = 0;
while (char_cnt-- > 0) {
if (*p >= '0' && *p <= '7')
digit = *p - '0';
else
return (l);
p++;
l <<= 3;
l |= digit;
}
return (l);
}
static int64_t
atol16(const char *p, unsigned char_cnt)
{
int64_t l;
int digit;
l = 0;
while (char_cnt-- > 0) {
if (*p >= 'a' && *p <= 'f')
digit = *p - 'a' + 10;
else if (*p >= 'A' && *p <= 'F')
digit = *p - 'A' + 10;
else if (*p >= '0' && *p <= '9')
digit = *p - '0';
else
return (l);
p++;
l <<= 4;
l |= digit;
}
return (l);
}
static void
record_hardlink(struct cpio *cpio, struct archive_entry *entry,
const struct stat *st)
{
struct links_entry *le;
/*
* First look in the list of multiply-linked files. If we've
* already dumped it, convert this entry to a hard link entry.
*/
for (le = cpio->links_head; le; le = le->next) {
if (le->dev == st->st_dev && le->ino == st->st_ino) {
archive_entry_set_hardlink(entry, le->name);
if (--le->links <= 0) {
if (le->previous != NULL)
le->previous->next = le->next;
if (le->next != NULL)
le->next->previous = le->previous;
if (cpio->links_head == le)
cpio->links_head = le->next;
free(le);
}
return;
}
}
le = malloc(sizeof(struct links_entry));
if (le == NULL)
__archive_errx(1, "Out of memory adding file to list");
if (cpio->links_head != NULL)
cpio->links_head->previous = le;
le->next = cpio->links_head;
le->previous = NULL;
cpio->links_head = le;
le->dev = st->st_dev;
le->ino = st->st_ino;
le->links = st->st_nlink - 1;
le->name = strdup(archive_entry_pathname(entry));
if (le->name == NULL)
__archive_errx(1, "Out of memory adding file to list");
}