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/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
/***
This file is part of systemd.
Copyright 2011 Lennart Poettering
systemd is free software; you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
systemd is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
#include <assert.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#ifdef HAVE_XZ
# include <lzma.h>
#endif
#ifdef HAVE_LZ4
# include <lz4.h>
#endif
#include "compress.h"
#include "macro.h"
#include "util.h"
#include "sparse-endian.h"
#include "journal-def.h"
#define ALIGN_8(l) ALIGN_TO(l, sizeof(size_t))
static const char* const object_compressed_table[_OBJECT_COMPRESSED_MAX] = {
[OBJECT_COMPRESSED_XZ] = "XZ",
[OBJECT_COMPRESSED_LZ4] = "LZ4",
};
DEFINE_STRING_TABLE_LOOKUP(object_compressed, int);
int compress_blob_xz(const void *src, uint64_t src_size, void *dst, size_t *dst_size) {
#ifdef HAVE_XZ
static const lzma_options_lzma opt = {
1u << 20u, NULL, 0, LZMA_LC_DEFAULT, LZMA_LP_DEFAULT,
LZMA_PB_DEFAULT, LZMA_MODE_FAST, 128, LZMA_MF_HC3, 4};
static const lzma_filter filters[2] = {
{LZMA_FILTER_LZMA2, (lzma_options_lzma*) &opt},
{LZMA_VLI_UNKNOWN, NULL}
};
lzma_ret ret;
size_t out_pos = 0;
assert(src);
assert(src_size > 0);
assert(dst);
assert(dst_size);
/* Returns < 0 if we couldn't compress the data or the
* compressed result is longer than the original */
if (src_size < 80)
return -ENOBUFS;
ret = lzma_stream_buffer_encode((lzma_filter*) filters, LZMA_CHECK_NONE, NULL,
src, src_size, dst, &out_pos, src_size - 1);
if (ret != LZMA_OK)
return -ENOBUFS;
*dst_size = out_pos;
return 0;
#else
return -EPROTONOSUPPORT;
#endif
}
int compress_blob_lz4(const void *src, uint64_t src_size, void *dst, size_t *dst_size) {
#ifdef HAVE_LZ4
int r;
assert(src);
assert(src_size > 0);
assert(dst);
assert(dst_size);
/* Returns < 0 if we couldn't compress the data or the
* compressed result is longer than the original */
if (src_size < 9)
return -ENOBUFS;
r = LZ4_compress_limitedOutput(src, dst + 8, src_size, src_size - 8 - 1);
if (r <= 0)
return -ENOBUFS;
*(le64_t*) dst = htole64(src_size);
*dst_size = r + 8;
return 0;
#else
return -EPROTONOSUPPORT;
#endif
}
int decompress_blob_xz(const void *src, uint64_t src_size,
void **dst, size_t *dst_alloc_size, size_t* dst_size, size_t dst_max) {
#ifdef HAVE_XZ
_cleanup_(lzma_end) lzma_stream s = LZMA_STREAM_INIT;
lzma_ret ret;
size_t space;
assert(src);
assert(src_size > 0);
assert(dst);
assert(dst_alloc_size);
assert(dst_size);
assert(*dst_alloc_size == 0 || *dst);
ret = lzma_stream_decoder(&s, UINT64_MAX, 0);
if (ret != LZMA_OK)
return -ENOMEM;
space = MIN(src_size * 2, dst_max ?: (size_t) -1);
if (!greedy_realloc(dst, dst_alloc_size, space, 1))
return -ENOMEM;
s.next_in = src;
s.avail_in = src_size;
s.next_out = *dst;
s.avail_out = space;
for (;;) {
size_t used;
ret = lzma_code(&s, LZMA_FINISH);
if (ret == LZMA_STREAM_END)
break;
else if (ret != LZMA_OK)
return -ENOMEM;
if (dst_max > 0 && (space - s.avail_out) >= dst_max)
break;
else if (dst_max > 0 && space == dst_max)
return -ENOBUFS;
used = space - s.avail_out;
space = MIN(2 * space, dst_max ?: (size_t) -1);
if (!greedy_realloc(dst, dst_alloc_size, space, 1))
return -ENOMEM;
s.avail_out = space - used;
s.next_out = *dst + used;
}
*dst_size = space - s.avail_out;
return 0;
#else
return -EPROTONOSUPPORT;
#endif
}
int decompress_blob_lz4(const void *src, uint64_t src_size,
void **dst, size_t *dst_alloc_size, size_t* dst_size, size_t dst_max) {
#ifdef HAVE_LZ4
char* out;
int r, size; /* LZ4 uses int for size */
assert(src);
assert(src_size > 0);
assert(dst);
assert(dst_alloc_size);
assert(dst_size);
assert(*dst_alloc_size == 0 || *dst);
if (src_size <= 8)
return -EBADMSG;
size = le64toh( *(le64_t*)src );
if (size < 0 || (le64_t) size != *(le64_t*)src)
return -EFBIG;
if ((size_t) size > *dst_alloc_size) {
out = realloc(*dst, size);
if (!out)
return -ENOMEM;
*dst = out;
*dst_alloc_size = size;
} else
out = *dst;
r = LZ4_decompress_safe(src + 8, out, src_size - 8, size);
if (r < 0 || r != size)
return -EBADMSG;
*dst_size = size;
return 0;
#else
return -EPROTONOSUPPORT;
#endif
}
int decompress_blob(int compression,
const void *src, uint64_t src_size,
void **dst, size_t *dst_alloc_size, size_t* dst_size, size_t dst_max) {
if (compression == OBJECT_COMPRESSED_XZ)
return decompress_blob_xz(src, src_size,
dst, dst_alloc_size, dst_size, dst_max);
else if (compression == OBJECT_COMPRESSED_LZ4)
return decompress_blob_lz4(src, src_size,
dst, dst_alloc_size, dst_size, dst_max);
else
return -EBADMSG;
}
int decompress_startswith_xz(const void *src, uint64_t src_size,
void **buffer, size_t *buffer_size,
const void *prefix, size_t prefix_len,
uint8_t extra) {
#ifdef HAVE_XZ
_cleanup_(lzma_end) lzma_stream s = LZMA_STREAM_INIT;
lzma_ret ret;
/* Checks whether the decompressed blob starts with the
* mentioned prefix. The byte extra needs to follow the
* prefix */
assert(src);
assert(src_size > 0);
assert(buffer);
assert(buffer_size);
assert(prefix);
assert(*buffer_size == 0 || *buffer);
ret = lzma_stream_decoder(&s, UINT64_MAX, 0);
if (ret != LZMA_OK)
return -EBADMSG;
if (!(greedy_realloc(buffer, buffer_size, ALIGN_8(prefix_len + 1), 1)))
return -ENOMEM;
s.next_in = src;
s.avail_in = src_size;
s.next_out = *buffer;
s.avail_out = *buffer_size;
for (;;) {
ret = lzma_code(&s, LZMA_FINISH);
if (ret != LZMA_STREAM_END && ret != LZMA_OK)
return -EBADMSG;
if (*buffer_size - s.avail_out >= prefix_len + 1)
return memcmp(*buffer, prefix, prefix_len) == 0 &&
((const uint8_t*) *buffer)[prefix_len] == extra;
if (ret == LZMA_STREAM_END)
return 0;
s.avail_out += *buffer_size;
if (!(greedy_realloc(buffer, buffer_size, *buffer_size * 2, 1)))
return -ENOMEM;
s.next_out = *buffer + *buffer_size - s.avail_out;
}
#else
return -EPROTONOSUPPORT;
#endif
}
int decompress_startswith_lz4(const void *src, uint64_t src_size,
void **buffer, size_t *buffer_size,
const void *prefix, size_t prefix_len,
uint8_t extra) {
#ifdef HAVE_LZ4
/* Checks whether the decompressed blob starts with the
* mentioned prefix. The byte extra needs to follow the
* prefix */
int r;
assert(src);
assert(src_size > 0);
assert(buffer);
assert(buffer_size);
assert(prefix);
assert(*buffer_size == 0 || *buffer);
if (src_size <= 8)
return -EBADMSG;
if (!(greedy_realloc(buffer, buffer_size, ALIGN_8(prefix_len + 1), 1)))
return -ENOMEM;
r = LZ4_decompress_safe_partial(src + 8, *buffer, src_size - 8,
prefix_len + 1, *buffer_size);
if (r < 0)
return -EBADMSG;
if ((unsigned) r >= prefix_len + 1)
return memcmp(*buffer, prefix, prefix_len) == 0 &&
((const uint8_t*) *buffer)[prefix_len] == extra;
else
return 0;
#else
return -EPROTONOSUPPORT;
#endif
}
int decompress_startswith(int compression,
const void *src, uint64_t src_size,
void **buffer, size_t *buffer_size,
const void *prefix, size_t prefix_len,
uint8_t extra) {
if (compression == OBJECT_COMPRESSED_XZ)
return decompress_startswith_xz(src, src_size,
buffer, buffer_size,
prefix, prefix_len,
extra);
else if (compression == OBJECT_COMPRESSED_LZ4)
return decompress_startswith_lz4(src, src_size,
buffer, buffer_size,
prefix, prefix_len,
extra);
else
return -EBADMSG;
}
int compress_stream_xz(int fdf, int fdt, off_t max_bytes) {
#ifdef HAVE_XZ
_cleanup_(lzma_end) lzma_stream s = LZMA_STREAM_INIT;
lzma_ret ret;
uint8_t buf[BUFSIZ], out[BUFSIZ];
lzma_action action = LZMA_RUN;
assert(fdf >= 0);
assert(fdt >= 0);
ret = lzma_easy_encoder(&s, LZMA_PRESET_DEFAULT, LZMA_CHECK_CRC64);
if (ret != LZMA_OK) {
log_error("Failed to initialize XZ encoder: code %d", ret);
return -EINVAL;
}
for (;;) {
if (s.avail_in == 0 && action == LZMA_RUN) {
size_t m = sizeof(buf);
ssize_t n;
if (max_bytes != -1 && m > (size_t) max_bytes)
m = max_bytes;
n = read(fdf, buf, m);
if (n < 0)
return -errno;
if (n == 0)
action = LZMA_FINISH;
else {
s.next_in = buf;
s.avail_in = n;
if (max_bytes != -1) {
assert(max_bytes >= n);
max_bytes -= n;
}
}
}
if (s.avail_out == 0) {
s.next_out = out;
s.avail_out = sizeof(out);
}
ret = lzma_code(&s, action);
if (ret != LZMA_OK && ret != LZMA_STREAM_END) {
log_error("Compression failed: code %d", ret);
return -EBADMSG;
}
if (s.avail_out == 0 || ret == LZMA_STREAM_END) {
ssize_t n, k;
n = sizeof(out) - s.avail_out;
errno = 0;
k = loop_write(fdt, out, n, false);
if (k < 0)
return k;
if (k != n)
return errno ? -errno : -EIO;
if (ret == LZMA_STREAM_END) {
log_debug("XZ compression finished (%"PRIu64" -> %"PRIu64" bytes, %.1f%%)",
s.total_in, s.total_out,
(double) s.total_out / s.total_in * 100);
return 0;
}
}
}
#else
return -EPROTONOSUPPORT;
#endif
}
#define LZ4_BUFSIZE (512*1024)
int compress_stream_lz4(int fdf, int fdt, off_t max_bytes) {
#ifdef HAVE_LZ4
_cleanup_free_ char *buf1 = NULL, *buf2 = NULL, *out = NULL;
char *buf;
LZ4_stream_t lz4_data = {};
le32_t header;
size_t total_in = 0, total_out = sizeof(header);
ssize_t n;
assert(fdf >= 0);
assert(fdt >= 0);
buf1 = malloc(LZ4_BUFSIZE);
buf2 = malloc(LZ4_BUFSIZE);
out = malloc(LZ4_COMPRESSBOUND(LZ4_BUFSIZE));
if (!buf1 || !buf2 || !out)
return log_oom();
buf = buf1;
for (;;) {
size_t m;
int r;
m = LZ4_BUFSIZE;
if (max_bytes != -1 && m > (size_t) max_bytes - total_in)
m = max_bytes - total_in;
n = read(fdf, buf, m);
if (n < 0)
return -errno;
if (n == 0)
break;
total_in += n;
r = LZ4_compress_limitedOutput_continue(&lz4_data, buf, out, n, n);
if (r == 0) {
log_debug("Compressed size exceeds original, aborting compression.");
return -ENOBUFS;
}
header = htole32(r);
errno = 0;
n = write(fdt, &header, sizeof(header));
if (n < 0)
return -errno;
if (n != sizeof(header))
return errno ? -errno : -EIO;
n = loop_write(fdt, out, r, false);
if (n < 0)
return n;
if (n != r)
return errno ? -errno : -EIO;
total_out += sizeof(header) + r;
buf = buf == buf1 ? buf2 : buf1;
}
header = htole32(0);
n = write(fdt, &header, sizeof(header));
if (n < 0)
return -errno;
if (n != sizeof(header))
return errno ? -errno : -EIO;
log_debug("LZ4 compression finished (%zu -> %zu bytes, %.1f%%)",
total_in, total_out,
(double) total_out / total_in * 100);
return 0;
#else
return -EPROTONOSUPPORT;
#endif
}
int decompress_stream_xz(int fdf, int fdt, off_t max_bytes) {
#ifdef HAVE_XZ
_cleanup_(lzma_end) lzma_stream s = LZMA_STREAM_INIT;
lzma_ret ret;
uint8_t buf[BUFSIZ], out[BUFSIZ];
lzma_action action = LZMA_RUN;
assert(fdf >= 0);
assert(fdt >= 0);
ret = lzma_stream_decoder(&s, UINT64_MAX, 0);
if (ret != LZMA_OK) {
log_error("Failed to initialize XZ decoder: code %d", ret);
return -ENOMEM;
}
for (;;) {
if (s.avail_in == 0 && action == LZMA_RUN) {
ssize_t n;
n = read(fdf, buf, sizeof(buf));
if (n < 0)
return -errno;
if (n == 0)
action = LZMA_FINISH;
else {
s.next_in = buf;
s.avail_in = n;
}
}
if (s.avail_out == 0) {
s.next_out = out;
s.avail_out = sizeof(out);
}
ret = lzma_code(&s, action);
if (ret != LZMA_OK && ret != LZMA_STREAM_END) {
log_error("Decompression failed: code %d", ret);
return -EBADMSG;
}
if (s.avail_out == 0 || ret == LZMA_STREAM_END) {
ssize_t n, k;
n = sizeof(out) - s.avail_out;
if (max_bytes != -1) {
if (max_bytes < n)
return -EFBIG;
max_bytes -= n;
}
errno = 0;
k = loop_write(fdt, out, n, false);
if (k < 0)
return k;
if (k != n)
return errno ? -errno : -EIO;
if (ret == LZMA_STREAM_END) {
log_debug("XZ decompression finished (%"PRIu64" -> %"PRIu64" bytes, %.1f%%)",
s.total_in, s.total_out,
(double) s.total_out / s.total_in * 100);
return 0;
}
}
}
#else
log_error("Cannot decompress file. Compiled without XZ support.");
return -EPROTONOSUPPORT;
#endif
}
int decompress_stream_lz4(int fdf, int fdt, off_t max_bytes) {
#ifdef HAVE_LZ4
_cleanup_free_ char *buf = NULL, *out = NULL;
size_t buf_size = 0;
LZ4_streamDecode_t lz4_data = {};
le32_t header;
size_t total_in = sizeof(header), total_out = 0;
assert(fdf >= 0);
assert(fdt >= 0);
out = malloc(4*LZ4_BUFSIZE);
if (!out)
return log_oom();
for (;;) {
ssize_t n, m;
int r;
n = read(fdf, &header, sizeof(header));
if (n < 0)
return -errno;
if (n != sizeof(header))
return errno ? -errno : -EIO;
m = le32toh(header);
if (m == 0)
break;
/* We refuse to use a bigger decompression buffer than
* the one used for compression by 4 times. This means
* that compression buffer size can be enlarged 4
* times. This can be changed, but old binaries might
* not accept buffers compressed by newer binaries then.
*/
if (m > LZ4_COMPRESSBOUND(LZ4_BUFSIZE * 4)) {
log_error("Compressed stream block too big: %zd bytes", m);
return -EBADMSG;
}
total_in += sizeof(header) + m;
if (!GREEDY_REALLOC(buf, buf_size, m))
return log_oom();
errno = 0;
n = loop_read(fdf, buf, m, false);
if (n < 0)
return n;
if (n != m)
return errno ? -errno : -EIO;
r = LZ4_decompress_safe_continue(&lz4_data, buf, out, m, 4*LZ4_BUFSIZE);
if (r <= 0)
log_error("LZ4 decompression failed.");
total_out += r;
if (max_bytes != -1 && total_out > (size_t) max_bytes) {
log_debug("Decompressed stream longer than %zd bytes", max_bytes);
return -EFBIG;
}
errno = 0;
n = loop_write(fdt, out, r, false);
if (n < 0)
return n;
if (n != r)
return errno ? -errno : -EIO;
}
log_debug("LZ4 decompression finished (%zu -> %zu bytes, %.1f%%)",
total_in, total_out,
(double) total_out / total_in * 100);
return 0;
#else
log_error("Cannot decompress file. Compiled without LZ4 support.");
return -EPROTONOSUPPORT;
#endif
}
int decompress_stream(const char *filename, int fdf, int fdt, off_t max_bytes) {
if (endswith(filename, ".lz4"))
return decompress_stream_lz4(fdf, fdt, max_bytes);
else if (endswith(filename, ".xz"))
return decompress_stream_xz(fdf, fdt, max_bytes);
else
return -EPROTONOSUPPORT;
}