/*-*- 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_continue(&lz4_data, buf, out, n); if (r == 0) { log_error("LZ4 compression failed."); return -EBADMSG; } 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; }