diff options
Diffstat (limited to 'src/libsystemd/libsystemd-journal-internal/compress.c')
-rw-r--r-- | src/libsystemd/libsystemd-journal-internal/compress.c | 682 |
1 files changed, 682 insertions, 0 deletions
diff --git a/src/libsystemd/libsystemd-journal-internal/compress.c b/src/libsystemd/libsystemd-journal-internal/compress.c new file mode 100644 index 0000000000..1933b87b00 --- /dev/null +++ b/src/libsystemd/libsystemd-journal-internal/compress.c @@ -0,0 +1,682 @@ +/*** + 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 <stdlib.h> +#include <string.h> +#include <sys/mman.h> +#include <unistd.h> + +#ifdef HAVE_XZ +#include <lzma.h> +#endif + +#ifdef HAVE_LZ4 +#include <lz4.h> +#include <lz4frame.h> +#endif + +#include "alloc-util.h" +#include "compress.h" +#include "fd-util.h" +#include "io-util.h" +#include "journal-def.h" +#include "macro.h" +#include "sparse-endian.h" +#include "string-table.h" +#include "string-util.h" +#include "util.h" + +#ifdef HAVE_LZ4 +DEFINE_TRIVIAL_CLEANUP_FUNC(LZ4F_compressionContext_t, LZ4F_freeCompressionContext); +DEFINE_TRIVIAL_CLEANUP_FUNC(LZ4F_decompressionContext_t, LZ4F_freeDecompressionContext); +#endif + +#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_alloc_size, 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[] = { + { 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_alloc_size > 0); + 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, dst_alloc_size); + 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_alloc_size, size_t *dst_size) { +#ifdef HAVE_LZ4 + int r; + + assert(src); + assert(src_size > 0); + assert(dst); + assert(dst_alloc_size > 0); + 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, (int) dst_alloc_size - 8); + 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 || (unsigned) size != le64toh(*(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; + size_t size; + + 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) + size = (unsigned) r; + else { + /* lz4 always tries to decode full "sequence", so in + * pathological cases might need to decompress the + * full field. */ + r = decompress_blob_lz4(src, src_size, buffer, buffer_size, &size, 0); + if (r < 0) + return r; + } + + if (size >= 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, uint64_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 %u", ret); + return -EINVAL; + } + + for (;;) { + if (s.avail_in == 0 && action == LZMA_RUN) { + size_t m = sizeof(buf); + ssize_t n; + + if (max_bytes != (uint64_t) -1 && (uint64_t) m > max_bytes) + m = (size_t) 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 != (uint64_t) -1) { + assert(max_bytes >= (uint64_t) 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 %u", ret); + return -EBADMSG; + } + + if (s.avail_out == 0 || ret == LZMA_STREAM_END) { + ssize_t n, k; + + n = sizeof(out) - s.avail_out; + + k = loop_write(fdt, out, n, false); + if (k < 0) + return k; + + 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*1024u) + +int compress_stream_lz4(int fdf, int fdt, uint64_t max_bytes) { + +#ifdef HAVE_LZ4 + LZ4F_errorCode_t c; + _cleanup_(LZ4F_freeCompressionContextp) LZ4F_compressionContext_t ctx = NULL; + _cleanup_free_ char *buf = NULL; + char *src = NULL; + size_t size, n, total_in = 0, total_out, offset = 0, frame_size; + struct stat st; + int r; + static const LZ4F_compressOptions_t options = { + .stableSrc = 1, + }; + static const LZ4F_preferences_t preferences = { + .frameInfo.blockSizeID = 5, + }; + + c = LZ4F_createCompressionContext(&ctx, LZ4F_VERSION); + if (LZ4F_isError(c)) + return -ENOMEM; + + if (fstat(fdf, &st) < 0) + return log_debug_errno(errno, "fstat() failed: %m"); + + frame_size = LZ4F_compressBound(LZ4_BUFSIZE, &preferences); + size = frame_size + 64*1024; /* add some space for header and trailer */ + buf = malloc(size); + if (!buf) + return -ENOMEM; + + n = offset = total_out = LZ4F_compressBegin(ctx, buf, size, &preferences); + if (LZ4F_isError(n)) + return -EINVAL; + + src = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fdf, 0); + if (src == MAP_FAILED) + return -errno; + + log_debug("Buffer size is %zu bytes, header size %zu bytes.", size, n); + + while (total_in < (size_t) st.st_size) { + ssize_t k; + + k = MIN(LZ4_BUFSIZE, st.st_size - total_in); + n = LZ4F_compressUpdate(ctx, buf + offset, size - offset, + src + total_in, k, &options); + if (LZ4F_isError(n)) { + r = -ENOTRECOVERABLE; + goto cleanup; + } + + total_in += k; + offset += n; + total_out += n; + + if (max_bytes != (uint64_t) -1 && total_out > (size_t) max_bytes) { + log_debug("Compressed stream longer than %zd bytes", max_bytes); + return -EFBIG; + } + + if (size - offset < frame_size + 4) { + k = loop_write(fdt, buf, offset, false); + if (k < 0) { + r = k; + goto cleanup; + } + offset = 0; + } + } + + n = LZ4F_compressEnd(ctx, buf + offset, size - offset, &options); + if (LZ4F_isError(n)) { + r = -ENOTRECOVERABLE; + goto cleanup; + } + + offset += n; + total_out += n; + r = loop_write(fdt, buf, offset, false); + if (r < 0) + goto cleanup; + + log_debug("LZ4 compression finished (%zu -> %zu bytes, %.1f%%)", + total_in, total_out, + (double) total_out / total_in * 100); + cleanup: + munmap(src, st.st_size); + return r; +#else + return -EPROTONOSUPPORT; +#endif +} + +int decompress_stream_xz(int fdf, int fdt, uint64_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_debug("Failed to initialize XZ decoder: code %u", 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_debug("Decompression failed: code %u", 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 != (uint64_t) -1) { + if (max_bytes < (uint64_t) n) + return -EFBIG; + + max_bytes -= n; + } + + k = loop_write(fdt, out, n, false); + if (k < 0) + return k; + + 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_debug("Cannot decompress file. Compiled without XZ support."); + return -EPROTONOSUPPORT; +#endif +} + +int decompress_stream_lz4(int in, int out, uint64_t max_bytes) { +#ifdef HAVE_LZ4 + size_t c; + _cleanup_(LZ4F_freeDecompressionContextp) LZ4F_decompressionContext_t ctx = NULL; + _cleanup_free_ char *buf = NULL; + char *src; + struct stat st; + int r = 0; + size_t total_in = 0, total_out = 0; + + c = LZ4F_createDecompressionContext(&ctx, LZ4F_VERSION); + if (LZ4F_isError(c)) + return -ENOMEM; + + if (fstat(in, &st) < 0) + return log_debug_errno(errno, "fstat() failed: %m"); + + buf = malloc(LZ4_BUFSIZE); + if (!buf) + return -ENOMEM; + + src = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, in, 0); + if (src == MAP_FAILED) + return -errno; + + while (total_in < (size_t) st.st_size) { + size_t produced = LZ4_BUFSIZE; + size_t used = st.st_size - total_in; + + c = LZ4F_decompress(ctx, buf, &produced, src + total_in, &used, NULL); + if (LZ4F_isError(c)) { + r = -EBADMSG; + goto cleanup; + } + + total_in += used; + total_out += produced; + + if (max_bytes != (uint64_t) -1 && total_out > (size_t) max_bytes) { + log_debug("Decompressed stream longer than %zd bytes", max_bytes); + r = -EFBIG; + goto cleanup; + } + + r = loop_write(out, buf, produced, false); + if (r < 0) + goto cleanup; + } + + log_debug("LZ4 decompression finished (%zu -> %zu bytes, %.1f%%)", + total_in, total_out, + (double) total_out / total_in * 100); + cleanup: + munmap(src, st.st_size); + return r; +#else + log_debug("Cannot decompress file. Compiled without LZ4 support."); + return -EPROTONOSUPPORT; +#endif +} + +int decompress_stream(const char *filename, int fdf, int fdt, uint64_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; +} |