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-rw-r--r--src/journal/compress.c677
1 files changed, 677 insertions, 0 deletions
diff --git a/src/journal/compress.c b/src/journal/compress.c
new file mode 100644
index 0000000..e95ce2b
--- /dev/null
+++ b/src/journal/compress.c
@@ -0,0 +1,677 @@
+/* SPDX-License-Identifier: LGPL-2.1+ */
+
+#include <inttypes.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/mman.h>
+#include <unistd.h>
+
+#if HAVE_XZ
+#include <lzma.h>
+#endif
+
+#if 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"
+
+#if 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) {
+#if 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) {
+#if 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_default(src, (char*)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) {
+
+#if 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 = *(uint8_t**)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) {
+
+#if 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((char*)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) {
+
+#if 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 (!IN_SET(ret, LZMA_OK, LZMA_STREAM_END))
+ 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 = *(uint8_t**)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) {
+#if 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((char*)src + 8, *buffer, src_size - 8,
+ prefix_len + 1, *buffer_size);
+ /* One lz4 < 1.8.3, we might get "failure" (r < 0), or "success" where
+ * just a part of the buffer is decompressed. But if we get a smaller
+ * amount of bytes than requested, we don't know whether there isn't enough
+ * data to fill the requested size or whether we just got a partial answer.
+ */
+ if (r < 0 || (size_t) r < prefix_len + 1) {
+ size_t size;
+
+ if (LZ4_versionNumber() >= 10803)
+ /* We trust that the newer lz4 decompresses the number of bytes we
+ * requested if available in the compressed string. */
+ return 0;
+
+ if (r > 0)
+ /* Compare what we have first, in case of mismatch we can
+ * shortcut the full comparison. */
+ if (memcmp(*buffer, prefix, r) != 0)
+ return 0;
+
+ /* Before version 1.8.3, lz4 always tries to decode full a "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 0;
+ }
+
+ return memcmp(*buffer, prefix, prefix_len) == 0 &&
+ ((const uint8_t*) *buffer)[prefix_len] == extra;
+#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) {
+#if 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 (!IN_SET(ret, LZMA_OK, 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) {
+
+#if 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 %"PRIu64" 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) {
+
+#if 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 (!IN_SET(ret, LZMA_OK, 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) {
+#if 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 %"PRIu64" 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,
+ total_in > 0 ? (double) total_out / total_in * 100 : 0.0);
+ 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;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-23 02:32:39 +0000