Commit a77a366b authored by Nick Mathewson's avatar Nick Mathewson 🦞
Browse files

Warn on zstd header/library version mismatch 

If we're going to potentially degrade performance in this case, we
may as well tell people so.
parent f98cb5d3

src/common/compress.c

+10 −0
Original line number Diff line number Diff line
@@ -663,3 +663,13 @@ tor_compress_init(void) 
  tor_zstd_init();

}



/** Warn if we had any problems while setting up our compression libraries.

 *

 * (This isn't part of tor_compress_init, since the logs aren't set up yet.)

 */

void

tor_compress_log_init_warnings(void)

{

  tor_zstd_warn_if_version_mismatched();

}

src/common/compress.h

+1 −0
Original line number Diff line number Diff line
@@ -87,6 +87,7 @@ void tor_compress_free_(tor_compress_state_t *state); 
size_t tor_compress_state_size(const tor_compress_state_t *state);



void tor_compress_init(void);

void tor_compress_log_init_warnings(void);



#endif /* !defined(TOR_COMPRESS_H) */

src/common/compress_zstd.c

+38 −8
Original line number Diff line number Diff line
@@ -58,21 +58,29 @@ tor_zstd_method_supported(void) 
#endif

}



/** Format a zstd version number as a string in <b>buf</b>. */

static void

tor_zstd_format_version(char *buf, size_t buflen, unsigned version_number)

{

  tor_snprintf(buf, buflen,

               "%u.%u.%u",

               version_number / 10000 % 100,

               version_number / 100 % 100,

               version_number % 100);

}



#define VERSION_STR_MAX_LEN 16 /* more than enough space for 99.99.99 */



/** Return a string representation of the version of the currently running

 * version of libzstd. Returns NULL if Zstandard is unsupported. */

const char *

tor_zstd_get_version_str(void)

{

#ifdef HAVE_ZSTD

  static char version_str[16];

  size_t version_number;

  static char version_str[VERSION_STR_MAX_LEN];



  version_number = ZSTD_versionNumber();

  tor_snprintf(version_str, sizeof(version_str),

               "%d.%d.%d",

               (int) version_number / 10000 % 100,

               (int) version_number / 100 % 100,

               (int) version_number % 100);

  tor_zstd_format_version(version_str, sizeof(version_str),

                          ZSTD_versionNumber());



  return version_str;

#else /* !(defined(HAVE_ZSTD)) */
@@ -487,6 +495,27 @@ tor_zstd_init(void) 
  atomic_counter_init(&total_zstd_allocation);

}



/** Warn if the header and library versions don't match. */

void

tor_zstd_warn_if_version_mismatched(void)

{

#ifdef HAVE_ZSTD

  if (! tor_zstd_can_use_static_apis()) {

    char header_version[VERSION_STR_MAX_LEN];

    char runtime_version[VERSION_STR_MAX_LEN];

    tor_zstd_format_version(header_version, sizeof(header_version),

                            ZSTD_VERSION_NUMBER);

    tor_zstd_format_version(runtime_version, sizeof(runtime_version),

                            ZSTD_versionNumber());



    log_warn(LD_GENERAL,

             "Tor was compiled with zstd %s, but is running with zstd %s. "

             "For safety, we'll avoid using advanced zstd functionality.",

             header_version, runtime_version);

  }

#endif

}



#ifdef TOR_UNIT_TESTS

/** Testing only: disable usage of static-only APIs, so we can make sure that

 * we still work without them. */
@@ -496,3 +525,4 @@ tor_zstd_set_static_apis_disabled_for_testing(int disabled) 
  static_apis_disable_for_testing = disabled;

}

#endif

src/common/compress_zstd.h

+1 −0
Original line number Diff line number Diff line
@@ -43,6 +43,7 @@ size_t tor_zstd_compress_state_size(const tor_zstd_compress_state_t *state); 
size_t tor_zstd_get_total_allocation(void);



void tor_zstd_init(void);

void tor_zstd_warn_if_version_mismatched(void);



#ifdef TOR_UNIT_TESTS

void tor_zstd_set_static_apis_disabled_for_testing(int disabled);

src/or/main.c

+2 −0
Original line number Diff line number Diff line
@@ -3323,6 +3323,8 @@ tor_init(int argc, char *argv[]) 
    if (strstr(version, "alpha") || strstr(version, "beta"))

      log_notice(LD_GENERAL, "This version is not a stable Tor release. "

                 "Expect more bugs than usual.");



    tor_compress_log_init_warnings();

  }



#ifdef HAVE_RUST