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authorAlexander Færøy <ahf@torproject.org>2017-04-18 22:19:29 +0200
committerNick Mathewson <nickm@torproject.org>2017-04-25 08:10:09 -0400
commit380736d045f85299121f044928170cff321ae852 (patch)
tree4b6590a5ee0a5c08e1e128fc8ee9bf0938e75bc8 /src/common
parentce1feae9d9a4366e3cd93a68416841d0c6a636c5 (diff)
downloadtor-380736d045f85299121f044928170cff321ae852.tar.gz
tor-380736d045f85299121f044928170cff321ae852.zip
Add Zstandard support.
See: https://bugs.torproject.org/21662
Diffstat (limited to 'src/common')
-rw-r--r--src/common/compress.c33
-rw-r--r--src/common/compress.h3
-rw-r--r--src/common/compress_zstd.c584
-rw-r--r--src/common/compress_zstd.h56
-rw-r--r--src/common/include.am2
5 files changed, 677 insertions, 1 deletions
diff --git a/src/common/compress.c b/src/common/compress.c
index 3c7a3c6392..dc86be7750 100644
--- a/src/common/compress.c
+++ b/src/common/compress.c
@@ -25,6 +25,7 @@
#include "compress.h"
#include "compress_lzma.h"
#include "compress_zlib.h"
+#include "compress_zstd.h"
/** @{ */
/* These macros define the maximum allowable compression factor. Anything of
@@ -85,6 +86,9 @@ tor_compress(char **out, size_t *out_len,
if (method == LZMA_METHOD)
return tor_lzma_compress(out, out_len, in, in_len, method);
+ if (method == ZSTD_METHOD)
+ return tor_zstd_compress(out, out_len, in, in_len, method);
+
return -1;
}
@@ -118,6 +122,12 @@ tor_uncompress(char **out, size_t *out_len,
complete_only,
protocol_warn_level);
+ if (method == ZSTD_METHOD)
+ return tor_zstd_uncompress(out, out_len, in, in_len,
+ method,
+ complete_only,
+ protocol_warn_level);
+
return -1;
}
@@ -136,6 +146,9 @@ detect_compression_method(const char *in, size_t in_len)
} else if (in_len > 3 &&
fast_memeq(in, "\x5d\x00\x00\x00", 4)) {
return LZMA_METHOD;
+ } else if (in_len > 3 &&
+ fast_memeq(in, "\x28\xb5\x2f\xfd", 4)) {
+ return ZSTD_METHOD;
} else {
return UNKNOWN_METHOD;
}
@@ -149,6 +162,7 @@ struct tor_compress_state_t {
union {
tor_zlib_compress_state_t *zlib_state;
tor_lzma_compress_state_t *lzma_state;
+ tor_zstd_compress_state_t *zstd_state;
} u; /**< Compression backend state. */
};
@@ -185,6 +199,16 @@ tor_compress_new(int compress, compress_method_t method,
state->u.lzma_state = lzma_state;
break;
}
+ case ZSTD_METHOD: {
+ tor_zstd_compress_state_t *zstd_state =
+ tor_zstd_compress_new(compress, method, compression_level);
+
+ if (zstd_state == NULL)
+ goto err;
+
+ state->u.zstd_state = zstd_state;
+ break;
+ }
case NO_METHOD:
case UNKNOWN_METHOD:
goto err;
@@ -226,6 +250,10 @@ tor_compress_process(tor_compress_state_t *state,
return tor_lzma_compress_process(state->u.lzma_state,
out, out_len, in, in_len,
finish);
+ case ZSTD_METHOD:
+ return tor_zstd_compress_process(state->u.zstd_state,
+ out, out_len, in, in_len,
+ finish);
case NO_METHOD:
case UNKNOWN_METHOD:
goto err;
@@ -250,6 +278,9 @@ tor_compress_free(tor_compress_state_t *state)
case LZMA_METHOD:
tor_lzma_compress_free(state->u.lzma_state);
break;
+ case ZSTD_METHOD:
+ tor_zstd_compress_free(state->u.zstd_state);
+ break;
case NO_METHOD:
case UNKNOWN_METHOD:
break;
@@ -270,6 +301,8 @@ tor_compress_state_size(const tor_compress_state_t *state)
return tor_zlib_compress_state_size(state->u.zlib_state);
case LZMA_METHOD:
return tor_lzma_compress_state_size(state->u.lzma_state);
+ case ZSTD_METHOD:
+ return tor_zstd_compress_state_size(state->u.zstd_state);
case NO_METHOD:
case UNKNOWN_METHOD:
goto err;
diff --git a/src/common/compress.h b/src/common/compress.h
index 3e3ab3a574..59e7a79061 100644
--- a/src/common/compress.h
+++ b/src/common/compress.h
@@ -19,7 +19,8 @@ typedef enum {
GZIP_METHOD=1,
ZLIB_METHOD=2,
LZMA_METHOD=3,
- UNKNOWN_METHOD=4
+ ZSTD_METHOD=4,
+ UNKNOWN_METHOD=5
} compress_method_t;
/**
diff --git a/src/common/compress_zstd.c b/src/common/compress_zstd.c
new file mode 100644
index 0000000000..e2eb292d5d
--- /dev/null
+++ b/src/common/compress_zstd.c
@@ -0,0 +1,584 @@
+/* Copyright (c) 2004, Roger Dingledine.
+ * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
+ * Copyright (c) 2007-2017, The Tor Project, Inc. */
+/* See LICENSE for licensing information */
+
+/**
+ * \file compress_zstd.c
+ * \brief Compression backend for Zstandard.
+ *
+ * This module should never be invoked directly. Use the compress module
+ * instead.
+ **/
+
+#include "orconfig.h"
+
+#include "util.h"
+#include "torlog.h"
+#include "compress.h"
+#include "compress_zstd.h"
+
+#ifdef HAVE_ZSTD
+#include <zstd.h>
+#include <zstd_errors.h>
+#endif
+
+/** Total number of bytes allocated for Zstandard state. */
+static size_t total_zstd_allocation = 0;
+
+/** Return a string representation of the version of the currently running
+ * version of libzstd. */
+const char *
+tor_zstd_get_version_str(void)
+{
+#ifdef HAVE_ZSTD
+ static char version_str[16];
+ size_t version_number;
+
+ version_number = ZSTD_versionNumber();
+ tor_snprintf(version_str, sizeof(version_str),
+ "%lu.%lu.%lu",
+ version_number / 10000 % 100,
+ version_number / 100 % 100,
+ version_number % 100);
+
+ return version_str;
+#else
+ return "N/A";
+#endif
+}
+
+/** Return a string representation of the version of the version of libzstd
+ * used at compilation. */
+const char *
+tor_zstd_get_header_version_str(void)
+{
+#ifdef HAVE_ZSTD
+ return ZSTD_VERSION_STRING;
+#else
+ return "N/A";
+#endif
+}
+
+/** Given <b>in_len</b> bytes at <b>in</b>, compress them into a newly
+ * allocated buffer, using the Zstandard method. Store the compressed string
+ * in *<b>out</b>, and its length in *<b>out_len</b>. Return 0 on success, -1
+ * on failure.
+ */
+int
+tor_zstd_compress(char **out, size_t *out_len,
+ const char *in, size_t in_len,
+ compress_method_t method)
+{
+#ifdef HAVE_ZSTD
+ ZSTD_CStream *stream = NULL;
+ size_t out_size, old_size;
+ size_t retval;
+
+ tor_assert(out);
+ tor_assert(out_len);
+ tor_assert(in);
+ tor_assert(in_len < UINT_MAX);
+ tor_assert(method == ZSTD_METHOD);
+
+ *out = NULL;
+
+ stream = ZSTD_createCStream();
+
+ if (stream == NULL) {
+ // Zstandard does not give us any useful error message to why this
+ // happened. See https://github.com/facebook/zstd/issues/398
+ log_warn(LD_GENERAL, "Error while creating Zstandard stream");
+ goto err;
+ }
+
+ retval = ZSTD_initCStream(stream,
+ tor_compress_memory_level(HIGH_COMPRESSION));
+
+ if (ZSTD_isError(retval)) {
+ log_warn(LD_GENERAL, "Zstandard stream initialization error: %s",
+ ZSTD_getErrorName(retval));
+ goto err;
+ }
+
+ // Assume 50% compression and update our buffer in case we need to.
+ out_size = in_len / 2;
+ if (out_size < 1024)
+ out_size = 1024;
+
+ *out = tor_malloc(out_size);
+ *out_len = 0;
+
+ ZSTD_inBuffer input = { in, in_len, 0 };
+ ZSTD_outBuffer output = { *out, out_size, 0 };
+
+ while (input.pos < input.size) {
+ retval = ZSTD_compressStream(stream, &output, &input);
+
+ if (ZSTD_isError(retval)) {
+ log_warn(LD_GENERAL, "Zstandard stream compression error: %s",
+ ZSTD_getErrorName(retval));
+ goto err;
+ }
+
+ if (input.pos < input.size && output.pos == output.size) {
+ old_size = out_size;
+ out_size *= 2;
+
+ if (out_size < old_size) {
+ log_warn(LD_GENERAL, "Size overflow in Zstandard compression.");
+ goto err;
+ }
+
+ if (out_size - output.pos > UINT_MAX) {
+ log_warn(LD_BUG, "Ran over unsigned int limit of Zstandard while "
+ "compressing.");
+ goto err;
+ }
+
+ output.dst = *out = tor_realloc(*out, out_size);
+ output.size = out_size;
+ }
+ }
+
+ while (1) {
+ retval = ZSTD_endStream(stream, &output);
+
+ if (retval == 0)
+ break;
+
+ if (ZSTD_isError(retval)) {
+ log_warn(LD_GENERAL, "Zstandard stream error: %s",
+ ZSTD_getErrorName(retval));
+ goto err;
+ }
+
+ if (output.pos == output.size) {
+ old_size = out_size;
+ out_size *= 2;
+
+ if (out_size < old_size) {
+ log_warn(LD_GENERAL, "Size overflow in Zstandard compression.");
+ goto err;
+ }
+
+ if (out_size - output.pos > UINT_MAX) {
+ log_warn(LD_BUG, "Ran over unsigned int limit of Zstandard while "
+ "compressing.");
+ goto err;
+ }
+
+ output.dst = *out = tor_realloc(*out, out_size);
+ output.size = out_size;
+ }
+ }
+
+ *out_len = output.pos;
+
+ if (tor_compress_is_compression_bomb(*out_len, in_len)) {
+ log_warn(LD_BUG, "We compressed something and got an insanely high "
+ "compression factor; other Tor instances would think "
+ "this is a compression bomb.");
+ goto err;
+ }
+
+ if (stream != NULL) {
+ ZSTD_freeCStream(stream);
+ }
+
+ return 0;
+
+ err:
+ if (stream != NULL) {
+ ZSTD_freeCStream(stream);
+ }
+
+ tor_free(*out);
+ return -1;
+#else // HAVE_ZSTD.
+ (void)out;
+ (void)out_len;
+ (void)in;
+ (void)in_len;
+ (void)method;
+
+ return -1;
+#endif // HAVE_ZSTD.
+}
+
+/** Given a Zstandard compressed string of total length <b>in_len</b> bytes at
+ * <b>in</b>, uncompress them into a newly allocated buffer. Store the
+ * uncompressed string in *<b>out</b>, and its length in *<b>out_len</b>.
+ * Return 0 on success, -1 on failure.
+ *
+ * If <b>complete_only</b> is true, we consider a truncated input as a failure;
+ * otherwise we decompress as much as we can. Warn about truncated or corrupt
+ * inputs at <b>protocol_warn_level</b>.
+ */
+int
+tor_zstd_uncompress(char **out, size_t *out_len,
+ const char *in, size_t in_len,
+ compress_method_t method,
+ int complete_only,
+ int protocol_warn_level)
+{
+#ifdef HAVE_ZSTD
+ ZSTD_DStream *stream = NULL;
+ size_t retval;
+ size_t out_size, old_size;
+
+ tor_assert(out);
+ tor_assert(out_len);
+ tor_assert(in);
+ tor_assert(in_len < UINT_MAX);
+ tor_assert(method == ZSTD_METHOD);
+
+ // FIXME(ahf): Handle this?
+ (void)complete_only;
+ (void)protocol_warn_level;
+
+ *out = NULL;
+
+ stream = ZSTD_createDStream();
+
+ if (stream == NULL) {
+ // Zstandard does not give us any useful error message to why this
+ // happened. See https://github.com/facebook/zstd/issues/398
+ log_warn(LD_GENERAL, "Error while creating Zstandard stream");
+ goto err;
+ }
+
+ retval = ZSTD_initDStream(stream);
+
+ if (ZSTD_isError(retval)) {
+ log_warn(LD_GENERAL, "Zstandard stream initialization error: %s",
+ ZSTD_getErrorName(retval));
+ goto err;
+ }
+
+ out_size = in_len * 2;
+ if (out_size < 1024)
+ out_size = 1024;
+
+ if (out_size >= SIZE_T_CEILING || out_size > UINT_MAX)
+ goto err;
+
+ *out = tor_malloc(out_size);
+ *out_len = 0;
+
+ ZSTD_inBuffer input = { in, in_len, 0 };
+ ZSTD_outBuffer output = { *out, out_size, 0 };
+
+ while (input.pos < input.size) {
+ retval = ZSTD_decompressStream(stream, &output, &input);
+
+ if (ZSTD_isError(retval)) {
+ log_warn(LD_GENERAL, "Zstandard stream decompression error: %s",
+ ZSTD_getErrorName(retval));
+ goto err;
+ }
+
+ if (input.pos < input.size && output.pos == output.size) {
+ old_size = out_size;
+ out_size *= 2;
+
+ if (out_size < old_size) {
+ log_warn(LD_GENERAL, "Size overflow in Zstandard compression.");
+ goto err;
+ }
+
+ if (tor_compress_is_compression_bomb(in_len, out_size)) {
+ log_warn(LD_GENERAL, "Input looks like a possible Zstandard "
+ "compression bomb. Not proceeding.");
+ goto err;
+ }
+
+ if (out_size >= SIZE_T_CEILING) {
+ log_warn(LD_BUG, "Hit SIZE_T_CEILING limit while uncompressing "
+ "Zstandard data.");
+ goto err;
+ }
+
+ if (out_size - output.pos > UINT_MAX) {
+ log_warn(LD_BUG, "Ran over unsigned int limit of Zstandard while "
+ "decompressing.");
+ goto err;
+ }
+
+ output.dst = *out = tor_realloc(*out, out_size);
+ output.size = out_size;
+ }
+ }
+
+ *out_len = output.pos;
+
+ if (stream != NULL) {
+ ZSTD_freeDStream(stream);
+ }
+
+ // NUL-terminate our output.
+ if (out_size == *out_len)
+ *out = tor_realloc(*out, out_size + 1);
+ (*out)[*out_len] = '\0';
+
+ return 0;
+
+ err:
+ if (stream != NULL) {
+ ZSTD_freeDStream(stream);
+ }
+
+ tor_free(*out);
+ return -1;
+#else // HAVE_ZSTD.
+ (void)out;
+ (void)out_len;
+ (void)in;
+ (void)in_len;
+ (void)method;
+ (void)complete_only;
+ (void)protocol_warn_level;
+
+ return -1;
+#endif // HAVE_ZSTD.
+}
+
+/** Internal Zstandard state for incremental compression/decompression.
+ * The body of this struct is not exposed. */
+struct tor_zstd_compress_state_t {
+#ifdef HAVE_ZSTD
+ union {
+ /** Compression stream. Used when <b>compress</b> is true. */
+ ZSTD_CStream *compress_stream;
+ /** Decompression stream. Used when <b>compress</b> is false. */
+ ZSTD_DStream *decompress_stream;
+ } u; /**< Zstandard stream objects. */
+#endif // HAVE_ZSTD.
+
+ int compress; /**< True if we are compressing; false if we are inflating */
+
+ /** Number of bytes read so far. Used to detect compression bombs. */
+ size_t input_so_far;
+ /** Number of bytes written so far. Used to detect compression bombs. */
+ size_t output_so_far;
+
+ /** Approximate number of bytes allocated for this object. */
+ size_t allocation;
+};
+
+/** Construct and return a tor_zstd_compress_state_t object using
+ * <b>method</b>. If <b>compress</b>, it's for compression; otherwise it's for
+ * decompression. */
+tor_zstd_compress_state_t *
+tor_zstd_compress_new(int compress,
+ compress_method_t method,
+ compression_level_t compression_level)
+{
+ tor_assert(method == ZSTD_METHOD);
+
+#ifdef HAVE_ZSTD
+ tor_zstd_compress_state_t *result;
+ size_t retval;
+
+ result = tor_malloc_zero(sizeof(tor_zstd_compress_state_t));
+ result->compress = compress;
+
+ // FIXME(ahf): We should either try to do the pre-calculation that is done
+ // with the zlib backend or use a custom allocator here where we pass our
+ // tor_zstd_compress_state_t as the opaque value.
+ result->allocation = 0;
+
+ if (compress) {
+ result->u.compress_stream = ZSTD_createCStream();
+
+ if (result->u.compress_stream == NULL) {
+ log_warn(LD_GENERAL, "Error while creating Zstandard stream");
+ goto err;
+ }
+
+ retval = ZSTD_initCStream(result->u.compress_stream,
+ tor_compress_memory_level(compression_level));
+
+ if (ZSTD_isError(retval)) {
+ log_warn(LD_GENERAL, "Zstandard stream initialization error: %s",
+ ZSTD_getErrorName(retval));
+ goto err;
+ }
+ } else {
+ result->u.decompress_stream = ZSTD_createDStream();
+
+ if (result->u.decompress_stream == NULL) {
+ log_warn(LD_GENERAL, "Error while creating Zstandard stream");
+ goto err;
+ }
+
+ retval = ZSTD_initDStream(result->u.decompress_stream);
+
+ if (ZSTD_isError(retval)) {
+ log_warn(LD_GENERAL, "Zstandard stream initialization error: %s",
+ ZSTD_getErrorName(retval));
+ goto err;
+ }
+ }
+
+ return result;
+
+ err:
+ if (compress) {
+ ZSTD_freeCStream(result->u.compress_stream);
+ } else {
+ ZSTD_freeDStream(result->u.decompress_stream);
+ }
+
+ tor_free(result);
+ return NULL;
+#else // HAVE_ZSTD.
+ (void)compress;
+ (void)method;
+ (void)compression_level;
+
+ return NULL;
+#endif // HAVE_ZSTD.
+}
+
+/** Compress/decompress some bytes using <b>state</b>. Read up to
+ * *<b>in_len</b> bytes from *<b>in</b>, and write up to *<b>out_len</b> bytes
+ * to *<b>out</b>, adjusting the values as we go. If <b>finish</b> is true,
+ * we've reached the end of the input.
+ *
+ * Return TOR_COMPRESS_DONE if we've finished the entire
+ * compression/decompression.
+ * Return TOR_COMPRESS_OK if we're processed everything from the input.
+ * Return TOR_COMPRESS_BUFFER_FULL if we're out of space on <b>out</b>.
+ * Return TOR_COMPRESS_ERROR if the stream is corrupt.
+ */
+tor_compress_output_t
+tor_zstd_compress_process(tor_zstd_compress_state_t *state,
+ char **out, size_t *out_len,
+ const char **in, size_t *in_len,
+ int finish)
+{
+#ifdef HAVE_ZSTD
+ size_t retval;
+
+ tor_assert(state != NULL);
+ tor_assert(*in_len <= UINT_MAX);
+ tor_assert(*out_len <= UINT_MAX);
+
+ ZSTD_inBuffer input = { *in, *in_len, 0 };
+ ZSTD_outBuffer output = { *out, *out_len, 0 };
+
+ if (state->compress) {
+ retval = ZSTD_compressStream(state->u.compress_stream,
+ &output, &input);
+ } else {
+ retval = ZSTD_decompressStream(state->u.decompress_stream,
+ &output, &input);
+ }
+
+ state->input_so_far += input.pos;
+ state->output_so_far += output.pos;
+
+ *out = (char *)output.dst + output.pos;
+ *out_len = output.size - output.pos;
+ *in = (char *)input.src + input.pos;
+ *in_len = input.size - input.pos;
+
+ if (! state->compress &&
+ tor_compress_is_compression_bomb(state->input_so_far,
+ state->output_so_far)) {
+ log_warn(LD_DIR, "Possible compression bomb; abandoning stream.");
+ return TOR_COMPRESS_ERROR;
+ }
+
+ if (ZSTD_isError(retval)) {
+ log_warn(LD_GENERAL, "Zstandard %s didn't finish: %s.",
+ state->compress ? "compression" : "decompression",
+ ZSTD_getErrorName(retval));
+ return TOR_COMPRESS_ERROR;
+ }
+
+ if (state->compress && !finish) {
+ retval = ZSTD_flushStream(state->u.compress_stream, &output);
+
+ *out = (char *)output.dst + output.pos;
+ *out_len = output.size - output.pos;
+
+ if (ZSTD_isError(retval)) {
+ log_warn(LD_GENERAL, "Zstandard compression unable to flush: %s.",
+ ZSTD_getErrorName(retval));
+ return TOR_COMPRESS_ERROR;
+ }
+
+ if (retval > 0)
+ return TOR_COMPRESS_BUFFER_FULL;
+ }
+
+ if (state->compress && finish) {
+ retval = ZSTD_endStream(state->u.compress_stream, &output);
+
+ *out = (char *)output.dst + output.pos;
+ *out_len = output.size - output.pos;
+
+ if (ZSTD_isError(retval)) {
+ log_warn(LD_GENERAL, "Zstandard compression unable to write "
+ "epilogue: %s.",
+ ZSTD_getErrorName(retval));
+ return TOR_COMPRESS_ERROR;
+ }
+
+ // endStream returns the number of bytes that is needed to write the
+ // epilogue.
+ if (retval > 0)
+ return TOR_COMPRESS_BUFFER_FULL;
+ }
+
+ return finish ? TOR_COMPRESS_DONE : TOR_COMPRESS_OK;
+#else // HAVE_ZSTD.
+ (void)state;
+ (void)out;
+ (void)out_len;
+ (void)in;
+ (void)in_len;
+ (void)finish;
+
+ return TOR_COMPRESS_ERROR;
+#endif // HAVE_ZSTD.
+}
+
+/** Deallocate <b>state</b>. */
+void
+tor_zstd_compress_free(tor_zstd_compress_state_t *state)
+{
+ if (state == NULL)
+ return;
+
+ total_zstd_allocation -= state->allocation;
+
+#ifdef HAVE_ZSTD
+ if (state->compress) {
+ ZSTD_freeCStream(state->u.compress_stream);
+ } else {
+ ZSTD_freeDStream(state->u.decompress_stream);
+ }
+#endif // HAVE_ZSTD.
+
+ tor_free(state);
+}
+
+/** Return the approximate number of bytes allocated for <b>state</b>. */
+size_t
+tor_zstd_compress_state_size(const tor_zstd_compress_state_t *state)
+{
+ tor_assert(state != NULL);
+ return state->allocation;
+}
+
+/** Return the approximate number of bytes allocated for all Zstandard
+ * states. */
+size_t
+tor_zstd_get_total_allocation(void)
+{
+ return total_zstd_allocation;
+}
+
diff --git a/src/common/compress_zstd.h b/src/common/compress_zstd.h
new file mode 100644
index 0000000000..ec83ba961e
--- /dev/null
+++ b/src/common/compress_zstd.h
@@ -0,0 +1,56 @@
+/* Copyright (c) 2003, Roger Dingledine
+ * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
+ * Copyright (c) 2007-2017, The Tor Project, Inc. */
+/* See LICENSE for licensing information */
+
+/**
+ * \file compress_zstd.h
+ * \brief Header for compress_zstd.c
+ **/
+
+#ifndef TOR_COMPRESS_ZSTD_H
+#define TOR_COMPRESS_ZSTD_H
+
+const char *
+tor_zstd_get_version_str(void);
+
+const char *
+tor_zstd_get_header_version_str(void);
+
+int
+tor_zstd_compress(char **out, size_t *out_len,
+ const char *in, size_t in_len,
+ compress_method_t method);
+
+int
+tor_zstd_uncompress(char **out, size_t *out_len,
+ const char *in, size_t in_len,
+ compress_method_t method,
+ int complete_only,
+ int protocol_warn_level);
+
+/** Internal state for an incremental Zstandard compression/decompression. */
+typedef struct tor_zstd_compress_state_t tor_zstd_compress_state_t;
+
+tor_zstd_compress_state_t *
+tor_zstd_compress_new(int compress,
+ compress_method_t method,
+ compression_level_t compression_level);
+
+tor_compress_output_t
+tor_zstd_compress_process(tor_zstd_compress_state_t *state,
+ char **out, size_t *out_len,
+ const char **in, size_t *in_len,
+ int finish);
+
+void
+tor_zstd_compress_free(tor_zstd_compress_state_t *state);
+
+size_t
+tor_zstd_compress_state_size(const tor_zstd_compress_state_t *state);
+
+size_t
+tor_zstd_get_total_allocation(void);
+
+#endif // TOR_COMPRESS_ZSTD_H.
+
diff --git a/src/common/include.am b/src/common/include.am
index 2682c22b32..e285ef5f86 100644
--- a/src/common/include.am
+++ b/src/common/include.am
@@ -108,6 +108,7 @@ LIBOR_CRYPTO_A_SRC = \
src/common/compress.c \
src/common/compress_lzma.c \
src/common/compress_zlib.c \
+ src/common/compress_zstd.c \
src/common/crypto.c \
src/common/crypto_pwbox.c \
src/common/crypto_s2k.c \
@@ -150,6 +151,7 @@ COMMONHEADERS = \
src/common/compress.h \
src/common/compress_lzma.h \
src/common/compress_zlib.h \
+ src/common/compress_zstd.h \
src/common/confline.h \
src/common/container.h \
src/common/crypto.h \