Fetching contributors…
Cannot retrieve contributors at this time
636 lines (562 sloc) 17.4 KB
/*-
* Copyright (c) 2007 Kai Wang
* Copyright (c) 2007 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: head/lib/libarchive/archive_read_support_format_ar.c 201101 2009-12-28 03:06:27Z kientzle $");
#ifdef HAVE_SYS_STAT_H
#include <sys/stat.h>
#endif
#ifdef HAVE_ERRNO_H
#include <errno.h>
#endif
#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif
#ifdef HAVE_STRING_H
#include <string.h>
#endif
#ifdef HAVE_LIMITS_H
#include <limits.h>
#endif
#include "archive.h"
#include "archive_entry.h"
#include "archive_private.h"
#include "archive_read_private.h"
struct ar {
int64_t entry_bytes_remaining;
/* unconsumed is purely to track data we've gotten from readahead,
* but haven't yet marked as consumed. Must be paired with
* entry_bytes_remaining usage/modification.
*/
size_t entry_bytes_unconsumed;
int64_t entry_offset;
int64_t entry_padding;
char *strtab;
size_t strtab_size;
char read_global_header;
};
/*
* Define structure of the "ar" header.
*/
#define AR_name_offset 0
#define AR_name_size 16
#define AR_date_offset 16
#define AR_date_size 12
#define AR_uid_offset 28
#define AR_uid_size 6
#define AR_gid_offset 34
#define AR_gid_size 6
#define AR_mode_offset 40
#define AR_mode_size 8
#define AR_size_offset 48
#define AR_size_size 10
#define AR_fmag_offset 58
#define AR_fmag_size 2
static int archive_read_format_ar_bid(struct archive_read *a, int);
static int archive_read_format_ar_cleanup(struct archive_read *a);
static int archive_read_format_ar_read_data(struct archive_read *a,
const void **buff, size_t *size, int64_t *offset);
static int archive_read_format_ar_skip(struct archive_read *a);
static int archive_read_format_ar_read_header(struct archive_read *a,
struct archive_entry *e);
static uint64_t ar_atol8(const char *p, unsigned char_cnt);
static uint64_t ar_atol10(const char *p, unsigned char_cnt);
static int ar_parse_gnu_filename_table(struct archive_read *a);
static int ar_parse_common_header(struct ar *ar, struct archive_entry *,
const char *h);
int
archive_read_support_format_ar(struct archive *_a)
{
struct archive_read *a = (struct archive_read *)_a;
struct ar *ar;
int r;
archive_check_magic(_a, ARCHIVE_READ_MAGIC,
ARCHIVE_STATE_NEW, "archive_read_support_format_ar");
ar = (struct ar *)malloc(sizeof(*ar));
if (ar == NULL) {
archive_set_error(&a->archive, ENOMEM,
"Can't allocate ar data");
return (ARCHIVE_FATAL);
}
memset(ar, 0, sizeof(*ar));
ar->strtab = NULL;
r = __archive_read_register_format(a,
ar,
"ar",
archive_read_format_ar_bid,
NULL,
archive_read_format_ar_read_header,
archive_read_format_ar_read_data,
archive_read_format_ar_skip,
NULL,
archive_read_format_ar_cleanup,
NULL,
NULL);
if (r != ARCHIVE_OK) {
free(ar);
return (r);
}
return (ARCHIVE_OK);
}
static int
archive_read_format_ar_cleanup(struct archive_read *a)
{
struct ar *ar;
ar = (struct ar *)(a->format->data);
if (ar->strtab)
free(ar->strtab);
free(ar);
(a->format->data) = NULL;
return (ARCHIVE_OK);
}
static int
archive_read_format_ar_bid(struct archive_read *a, int best_bid)
{
const void *h;
(void)best_bid; /* UNUSED */
/*
* Verify the 8-byte file signature.
* TODO: Do we need to check more than this?
*/
if ((h = __archive_read_ahead(a, 8, NULL)) == NULL)
return (-1);
if (memcmp(h, "!<arch>\n", 8) == 0) {
return (64);
}
return (-1);
}
static int
_ar_read_header(struct archive_read *a, struct archive_entry *entry,
struct ar *ar, const char *h, size_t *unconsumed)
{
char filename[AR_name_size + 1];
uint64_t number; /* Used to hold parsed numbers before validation. */
size_t bsd_name_length, entry_size;
char *p, *st;
const void *b;
int r;
/* Verify the magic signature on the file header. */
if (strncmp(h + AR_fmag_offset, "`\n", 2) != 0) {
archive_set_error(&a->archive, EINVAL,
"Incorrect file header signature");
return (ARCHIVE_FATAL);
}
/* Copy filename into work buffer. */
strncpy(filename, h + AR_name_offset, AR_name_size);
filename[AR_name_size] = '\0';
/*
* Guess the format variant based on the filename.
*/
if (a->archive.archive_format == ARCHIVE_FORMAT_AR) {
/* We don't already know the variant, so let's guess. */
/*
* Biggest clue is presence of '/': GNU starts special
* filenames with '/', appends '/' as terminator to
* non-special names, so anything with '/' should be
* GNU except for BSD long filenames.
*/
if (strncmp(filename, "#1/", 3) == 0)
a->archive.archive_format = ARCHIVE_FORMAT_AR_BSD;
else if (strchr(filename, '/') != NULL)
a->archive.archive_format = ARCHIVE_FORMAT_AR_GNU;
else if (strncmp(filename, "__.SYMDEF", 9) == 0)
a->archive.archive_format = ARCHIVE_FORMAT_AR_BSD;
/*
* XXX Do GNU/SVR4 'ar' programs ever omit trailing '/'
* if name exactly fills 16-byte field? If so, we
* can't assume entries without '/' are BSD. XXX
*/
}
/* Update format name from the code. */
if (a->archive.archive_format == ARCHIVE_FORMAT_AR_GNU)
a->archive.archive_format_name = "ar (GNU/SVR4)";
else if (a->archive.archive_format == ARCHIVE_FORMAT_AR_BSD)
a->archive.archive_format_name = "ar (BSD)";
else
a->archive.archive_format_name = "ar";
/*
* Remove trailing spaces from the filename. GNU and BSD
* variants both pad filename area out with spaces.
* This will only be wrong if GNU/SVR4 'ar' implementations
* omit trailing '/' for 16-char filenames and we have
* a 16-char filename that ends in ' '.
*/
p = filename + AR_name_size - 1;
while (p >= filename && *p == ' ') {
*p = '\0';
p--;
}
/*
* Remove trailing slash unless first character is '/'.
* (BSD entries never end in '/', so this will only trim
* GNU-format entries. GNU special entries start with '/'
* and are not terminated in '/', so we don't trim anything
* that starts with '/'.)
*/
if (filename[0] != '/' && p > filename && *p == '/') {
*p = '\0';
}
if (p < filename) {
archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
"Found entry with empty filename");
return (ARCHIVE_FATAL);
}
/*
* '//' is the GNU filename table.
* Later entries can refer to names in this table.
*/
if (strcmp(filename, "//") == 0) {
/* This must come before any call to _read_ahead. */
ar_parse_common_header(ar, entry, h);
archive_entry_copy_pathname(entry, filename);
archive_entry_set_filetype(entry, AE_IFREG);
/* Get the size of the filename table. */
number = ar_atol10(h + AR_size_offset, AR_size_size);
if (number > SIZE_MAX) {
archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
"Filename table too large");
return (ARCHIVE_FATAL);
}
entry_size = (size_t)number;
if (entry_size == 0) {
archive_set_error(&a->archive, EINVAL,
"Invalid string table");
return (ARCHIVE_FATAL);
}
if (ar->strtab != NULL) {
archive_set_error(&a->archive, EINVAL,
"More than one string tables exist");
return (ARCHIVE_FATAL);
}
/* Read the filename table into memory. */
st = malloc(entry_size);
if (st == NULL) {
archive_set_error(&a->archive, ENOMEM,
"Can't allocate filename table buffer");
return (ARCHIVE_FATAL);
}
ar->strtab = st;
ar->strtab_size = entry_size;
if (*unconsumed) {
__archive_read_consume(a, *unconsumed);
*unconsumed = 0;
}
if ((b = __archive_read_ahead(a, entry_size, NULL)) == NULL)
return (ARCHIVE_FATAL);
memcpy(st, b, entry_size);
__archive_read_consume(a, entry_size);
/* All contents are consumed. */
ar->entry_bytes_remaining = 0;
archive_entry_set_size(entry, ar->entry_bytes_remaining);
/* Parse the filename table. */
return (ar_parse_gnu_filename_table(a));
}
/*
* GNU variant handles long filenames by storing /<number>
* to indicate a name stored in the filename table.
* XXX TODO: Verify that it's all digits... Don't be fooled
* by "/9xyz" XXX
*/
if (filename[0] == '/' && filename[1] >= '0' && filename[1] <= '9') {
number = ar_atol10(h + AR_name_offset + 1, AR_name_size - 1);
/*
* If we can't look up the real name, warn and return
* the entry with the wrong name.
*/
if (ar->strtab == NULL || number > ar->strtab_size) {
archive_set_error(&a->archive, EINVAL,
"Can't find long filename for GNU/SVR4 archive entry");
archive_entry_copy_pathname(entry, filename);
/* Parse the time, owner, mode, size fields. */
ar_parse_common_header(ar, entry, h);
return (ARCHIVE_FATAL);
}
archive_entry_copy_pathname(entry, &ar->strtab[(size_t)number]);
/* Parse the time, owner, mode, size fields. */
return (ar_parse_common_header(ar, entry, h));
}
/*
* BSD handles long filenames by storing "#1/" followed by the
* length of filename as a decimal number, then prepends the
* the filename to the file contents.
*/
if (strncmp(filename, "#1/", 3) == 0) {
/* Parse the time, owner, mode, size fields. */
/* This must occur before _read_ahead is called again. */
ar_parse_common_header(ar, entry, h);
/* Parse the size of the name, adjust the file size. */
number = ar_atol10(h + AR_name_offset + 3, AR_name_size - 3);
bsd_name_length = (size_t)number;
/* Guard against the filename + trailing NUL
* overflowing a size_t and against the filename size
* being larger than the entire entry. */
if (number > (uint64_t)(bsd_name_length + 1)
|| (int64_t)bsd_name_length > ar->entry_bytes_remaining) {
archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
"Bad input file size");
return (ARCHIVE_FATAL);
}
ar->entry_bytes_remaining -= bsd_name_length;
/* Adjust file size reported to client. */
archive_entry_set_size(entry, ar->entry_bytes_remaining);
if (*unconsumed) {
__archive_read_consume(a, *unconsumed);
*unconsumed = 0;
}
/* Read the long name into memory. */
if ((b = __archive_read_ahead(a, bsd_name_length, NULL)) == NULL) {
archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
"Truncated input file");
return (ARCHIVE_FATAL);
}
/* Store it in the entry. */
p = (char *)malloc(bsd_name_length + 1);
if (p == NULL) {
archive_set_error(&a->archive, ENOMEM,
"Can't allocate fname buffer");
return (ARCHIVE_FATAL);
}
strncpy(p, b, bsd_name_length);
p[bsd_name_length] = '\0';
__archive_read_consume(a, bsd_name_length);
archive_entry_copy_pathname(entry, p);
free(p);
return (ARCHIVE_OK);
}
/*
* "/" is the SVR4/GNU archive symbol table.
*/
if (strcmp(filename, "/") == 0) {
archive_entry_copy_pathname(entry, "/");
/* Parse the time, owner, mode, size fields. */
r = ar_parse_common_header(ar, entry, h);
/* Force the file type to a regular file. */
archive_entry_set_filetype(entry, AE_IFREG);
return (r);
}
/*
* "__.SYMDEF" is a BSD archive symbol table.
*/
if (strcmp(filename, "__.SYMDEF") == 0) {
archive_entry_copy_pathname(entry, filename);
/* Parse the time, owner, mode, size fields. */
return (ar_parse_common_header(ar, entry, h));
}
/*
* Otherwise, this is a standard entry. The filename
* has already been trimmed as much as possible, based
* on our current knowledge of the format.
*/
archive_entry_copy_pathname(entry, filename);
return (ar_parse_common_header(ar, entry, h));
}
static int
archive_read_format_ar_read_header(struct archive_read *a,
struct archive_entry *entry)
{
struct ar *ar = (struct ar*)(a->format->data);
size_t unconsumed;
const void *header_data;
int ret;
if (!ar->read_global_header) {
/*
* We are now at the beginning of the archive,
* so we need first consume the ar global header.
*/
__archive_read_consume(a, 8);
ar->read_global_header = 1;
/* Set a default format code for now. */
a->archive.archive_format = ARCHIVE_FORMAT_AR;
}
/* Read the header for the next file entry. */
if ((header_data = __archive_read_ahead(a, 60, NULL)) == NULL)
/* Broken header. */
return (ARCHIVE_EOF);
unconsumed = 60;
ret = _ar_read_header(a, entry, ar, (const char *)header_data, &unconsumed);
if (unconsumed)
__archive_read_consume(a, unconsumed);
return ret;
}
static int
ar_parse_common_header(struct ar *ar, struct archive_entry *entry,
const char *h)
{
uint64_t n;
/* Copy remaining header */
archive_entry_set_mtime(entry,
(time_t)ar_atol10(h + AR_date_offset, AR_date_size), 0L);
archive_entry_set_uid(entry,
(uid_t)ar_atol10(h + AR_uid_offset, AR_uid_size));
archive_entry_set_gid(entry,
(gid_t)ar_atol10(h + AR_gid_offset, AR_gid_size));
archive_entry_set_mode(entry,
(mode_t)ar_atol8(h + AR_mode_offset, AR_mode_size));
n = ar_atol10(h + AR_size_offset, AR_size_size);
ar->entry_offset = 0;
ar->entry_padding = n % 2;
archive_entry_set_size(entry, n);
ar->entry_bytes_remaining = n;
return (ARCHIVE_OK);
}
static int
archive_read_format_ar_read_data(struct archive_read *a,
const void **buff, size_t *size, int64_t *offset)
{
ssize_t bytes_read;
struct ar *ar;
ar = (struct ar *)(a->format->data);
if (ar->entry_bytes_unconsumed) {
__archive_read_consume(a, ar->entry_bytes_unconsumed);
ar->entry_bytes_unconsumed = 0;
}
if (ar->entry_bytes_remaining > 0) {
*buff = __archive_read_ahead(a, 1, &bytes_read);
if (bytes_read == 0) {
archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
"Truncated ar archive");
return (ARCHIVE_FATAL);
}
if (bytes_read < 0)
return (ARCHIVE_FATAL);
if (bytes_read > ar->entry_bytes_remaining)
bytes_read = (ssize_t)ar->entry_bytes_remaining;
*size = bytes_read;
ar->entry_bytes_unconsumed = bytes_read;
*offset = ar->entry_offset;
ar->entry_offset += bytes_read;
ar->entry_bytes_remaining -= bytes_read;
return (ARCHIVE_OK);
} else {
int64_t skipped = __archive_read_consume(a, ar->entry_padding);
if (skipped >= 0) {
ar->entry_padding -= skipped;
}
if (ar->entry_padding) {
if (skipped >= 0) {
archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
"Truncated ar archive- failed consuming padding");
}
return (ARCHIVE_FATAL);
}
*buff = NULL;
*size = 0;
*offset = ar->entry_offset;
return (ARCHIVE_EOF);
}
}
static int
archive_read_format_ar_skip(struct archive_read *a)
{
int64_t bytes_skipped;
struct ar* ar;
ar = (struct ar *)(a->format->data);
bytes_skipped = __archive_read_consume(a,
ar->entry_bytes_remaining + ar->entry_padding
+ ar->entry_bytes_unconsumed);
if (bytes_skipped < 0)
return (ARCHIVE_FATAL);
ar->entry_bytes_remaining = 0;
ar->entry_bytes_unconsumed = 0;
ar->entry_padding = 0;
return (ARCHIVE_OK);
}
static int
ar_parse_gnu_filename_table(struct archive_read *a)
{
struct ar *ar;
char *p;
size_t size;
ar = (struct ar*)(a->format->data);
size = ar->strtab_size;
for (p = ar->strtab; p < ar->strtab + size - 1; ++p) {
if (*p == '/') {
*p++ = '\0';
if (*p != '\n')
goto bad_string_table;
*p = '\0';
}
}
/*
* GNU ar always pads the table to an even size.
* The pad character is either '\n' or '`'.
*/
if (p != ar->strtab + size && *p != '\n' && *p != '`')
goto bad_string_table;
/* Enforce zero termination. */
ar->strtab[size - 1] = '\0';
return (ARCHIVE_OK);
bad_string_table:
archive_set_error(&a->archive, EINVAL,
"Invalid string table");
free(ar->strtab);
ar->strtab = NULL;
return (ARCHIVE_FATAL);
}
static uint64_t
ar_atol8(const char *p, unsigned char_cnt)
{
uint64_t l, limit, last_digit_limit;
unsigned int digit, base;
base = 8;
limit = UINT64_MAX / base;
last_digit_limit = UINT64_MAX % base;
while ((*p == ' ' || *p == '\t') && char_cnt-- > 0)
p++;
l = 0;
digit = *p - '0';
while (*p >= '0' && digit < base && char_cnt-- > 0) {
if (l>limit || (l == limit && digit > last_digit_limit)) {
l = UINT64_MAX; /* Truncate on overflow. */
break;
}
l = (l * base) + digit;
digit = *++p - '0';
}
return (l);
}
static uint64_t
ar_atol10(const char *p, unsigned char_cnt)
{
uint64_t l, limit, last_digit_limit;
unsigned int base, digit;
base = 10;
limit = UINT64_MAX / base;
last_digit_limit = UINT64_MAX % base;
while ((*p == ' ' || *p == '\t') && char_cnt-- > 0)
p++;
l = 0;
digit = *p - '0';
while (*p >= '0' && digit < base && char_cnt-- > 0) {
if (l > limit || (l == limit && digit > last_digit_limit)) {
l = UINT64_MAX; /* Truncate on overflow. */
break;
}
l = (l * base) + digit;
digit = *++p - '0';
}
return (l);
}