commit cf2f7a1bea3beb03368fc309e7bf7d9ba598b6dd Author: Alexander Færøy <ahf@torproject.org> Date: Thu May 11 03:32:51 2017 +0200 Decide compression method in the various handle_* functions(). See: https://bugs.torproject.org/21667 --- src/or/directory.c | 89 ++++++++++++++++++++++++++++++++++-------------------- 1 file changed, 56 insertions(+), 33 deletions(-) diff --git a/src/or/directory.c b/src/or/directory.c index ca49388..78e0fb3 100644 --- a/src/or/directory.c +++ b/src/or/directory.c @@ -3706,6 +3706,22 @@ find_best_diff(const smartlist_t *digests, int flav, return NULL; } +/** Try to find the best supported compression method possible from a given + * <b>compression_methods</b>. Return NO_METHOD if no mutually supported + * compression method could be found. */ +static compress_method_t +find_best_compression_method(unsigned compression_methods) +{ + unsigned u; + for (u = 0; u < ARRAY_LENGTH(srv_meth_pref_precompressed); ++u) { + compress_method_t method = srv_meth_pref_precompressed[u]; + if (compression_methods & (1u<<method)) + return method; + } + + return NO_METHOD; +} + /** Helper function for GET /tor/status-vote/current/consensus */ static int @@ -3713,7 +3729,8 @@ handle_get_current_consensus(dir_connection_t *conn, const get_handler_args_t *args) { const char *url = args->url; - const int compressed = args->compression_supported & (1u << ZLIB_METHOD); + const compress_method_t compress_method = + find_best_compression_method(args->compression_supported); const time_t if_modified_since = args->if_modified_since; int clear_spool = 0; @@ -3786,11 +3803,11 @@ handle_get_current_consensus(dir_connection_t *conn, } else if (flavor) { spooled = spooled_resource_new(DIR_SPOOL_NETWORKSTATUS, (uint8_t*)flavor, strlen(flavor)); - compression_used = compressed ? ZLIB_METHOD : NO_METHOD; + compression_used = compress_method; } else { spooled = spooled_resource_new(DIR_SPOOL_NETWORKSTATUS, NULL, 0); - compression_used = compressed ? ZLIB_METHOD : NO_METHOD; + compression_used = compress_method; } tor_free(flavor); smartlist_add(conn->spool, spooled); @@ -3806,7 +3823,7 @@ handle_get_current_consensus(dir_connection_t *conn, size_t size_guess = 0; int n_expired = 0; dirserv_spool_remove_missing_and_guess_size(conn, if_modified_since, - compressed, + compress_method != NO_METHOD, &size_guess, &n_expired); @@ -3848,8 +3865,8 @@ handle_get_current_consensus(dir_connection_t *conn, write_http_response_header(conn, -1, compression_used, smartlist_len(conn->spool) == 1 ? lifetime : 0); - if (! compressed) - conn->compress_state = tor_compress_new(0, ZLIB_METHOD, + if (compress_method != NO_METHOD) + conn->compress_state = tor_compress_new(0, compress_method, HIGH_COMPRESSION); /* Prime the connection with some data. */ @@ -3870,7 +3887,8 @@ static int handle_get_status_vote(dir_connection_t *conn, const get_handler_args_t *args) { const char *url = args->url; - const int compressed = args->compression_supported & (1u << ZLIB_METHOD); + const compress_method_t compress_method = + find_best_compression_method(args->compression_supported); { int current; ssize_t body_len = 0; @@ -3927,13 +3945,13 @@ handle_get_status_vote(dir_connection_t *conn, const get_handler_args_t *args) goto vote_done; } SMARTLIST_FOREACH(dir_items, cached_dir_t *, d, - body_len += compressed + body_len += compress_method != NO_METHOD ? d->dir_compressed_len : d->dir_len); estimated_len += body_len; SMARTLIST_FOREACH(items, const char *, item, { size_t ln = strlen(item); - if (compressed) { + if (compress_method != NO_METHOD) { estimated_len += ln/2; } else { body_len += ln; estimated_len += ln; @@ -3945,12 +3963,12 @@ handle_get_status_vote(dir_connection_t *conn, const get_handler_args_t *args) goto vote_done; } write_http_response_header(conn, body_len ? body_len : -1, - compressed ? ZLIB_METHOD : NO_METHOD, + compress_method, lifetime); if (smartlist_len(items)) { - if (compressed) { - conn->compress_state = tor_compress_new(1, ZLIB_METHOD, + if (compress_method != NO_METHOD) { + conn->compress_state = tor_compress_new(1, compress_method, choose_compression_level(estimated_len)); SMARTLIST_FOREACH(items, const char *, c, connection_write_to_buf_compress(c, strlen(c), conn, 0)); @@ -3961,9 +3979,9 @@ handle_get_status_vote(dir_connection_t *conn, const get_handler_args_t *args) } } else { SMARTLIST_FOREACH(dir_items, cached_dir_t *, d, - connection_write_to_buf(compressed + connection_write_to_buf(compress_method != NO_METHOD ? d->dir_compressed : d->dir, - compressed + compress_method != NO_METHOD ? d->dir_compressed_len : d->dir_len, TO_CONN(conn))); } @@ -3982,7 +4000,8 @@ static int handle_get_microdesc(dir_connection_t *conn, const get_handler_args_t *args) { const char *url = args->url; - const int compressed = args->compression_supported & (1u << ZLIB_METHOD); + const compress_method_t compress_method = + find_best_compression_method(args->compression_supported); int clear_spool = 1; { conn->spool = smartlist_new(); @@ -3993,7 +4012,8 @@ handle_get_microdesc(dir_connection_t *conn, const get_handler_args_t *args) DSR_DIGEST256|DSR_BASE64|DSR_SORT_UNIQ); size_t size_guess = 0; - dirserv_spool_remove_missing_and_guess_size(conn, 0, compressed, + dirserv_spool_remove_missing_and_guess_size(conn, 0, + compress_method != NO_METHOD, &size_guess, NULL); if (smartlist_len(conn->spool) == 0) { write_http_status_line(conn, 404, "Not found"); @@ -4009,11 +4029,11 @@ handle_get_microdesc(dir_connection_t *conn, const get_handler_args_t *args) clear_spool = 0; write_http_response_header(conn, -1, - compressed ? ZLIB_METHOD : NO_METHOD, + compress_method, MICRODESC_CACHE_LIFETIME); - if (compressed) - conn->compress_state = tor_compress_new(1, ZLIB_METHOD, + if (compress_method != NO_METHOD) + conn->compress_state = tor_compress_new(1, compress_method, choose_compression_level(size_guess)); const int initial_flush_result = connection_dirserv_flushed_some(conn); @@ -4034,7 +4054,8 @@ static int handle_get_descriptor(dir_connection_t *conn, const get_handler_args_t *args) { const char *url = args->url; - const int compressed = args->compression_supported & (1u << ZLIB_METHOD); + const compress_method_t compress_method = + find_best_compression_method(args->compression_supported); const or_options_t *options = get_options(); int clear_spool = 1; if (!strcmpstart(url,"/tor/server/") || @@ -4073,8 +4094,8 @@ handle_get_descriptor(dir_connection_t *conn, const get_handler_args_t *args) size_t size_guess = 0; int n_expired = 0; dirserv_spool_remove_missing_and_guess_size(conn, publish_cutoff, - compressed, &size_guess, - &n_expired); + compress_method != NO_METHOD, + &size_guess, &n_expired); /* If we are the bridge authority and the descriptor is a bridge * descriptor, remember that we served this descriptor for desc stats. */ @@ -4104,11 +4125,9 @@ handle_get_descriptor(dir_connection_t *conn, const get_handler_args_t *args) dir_conn_clear_spool(conn); goto done; } - write_http_response_header(conn, -1, - compressed ? ZLIB_METHOD : NO_METHOD, - cache_lifetime); - if (compressed) - conn->compress_state = tor_compress_new(1, ZLIB_METHOD, + write_http_response_header(conn, -1, compress_method, cache_lifetime); + if (compress_method != NO_METHOD) + conn->compress_state = tor_compress_new(1, compress_method, choose_compression_level(size_guess)); clear_spool = 0; /* Prime the connection with some data. */ @@ -4129,7 +4148,8 @@ static int handle_get_keys(dir_connection_t *conn, const get_handler_args_t *args) { const char *url = args->url; - const int compressed = args->compression_supported & (1u << ZLIB_METHOD); + const compress_method_t compress_method = + find_best_compression_method(args->compression_supported); const time_t if_modified_since = args->if_modified_since; { smartlist_t *certs = smartlist_new(); @@ -4192,16 +4212,19 @@ handle_get_keys(dir_connection_t *conn, const get_handler_args_t *args) SMARTLIST_FOREACH(certs, authority_cert_t *, c, len += c->cache_info.signed_descriptor_len); - if (global_write_bucket_low(TO_CONN(conn), compressed?len/2:len, 2)) { + if (global_write_bucket_low(TO_CONN(conn), + compress_method != NO_METHOD ? len/2 : len, + 2)) { write_http_status_line(conn, 503, "Directory busy, try again later"); goto keys_done; } - write_http_response_header(conn, compressed?-1:len, - compressed ? ZLIB_METHOD : NO_METHOD, + write_http_response_header(conn, + compress_method != NO_METHOD ? -1 : len, + compress_method, 60*60); - if (compressed) { - conn->compress_state = tor_compress_new(1, ZLIB_METHOD, + if (compress_method != NO_METHOD) { + conn->compress_state = tor_compress_new(1, compress_method, choose_compression_level(len)); SMARTLIST_FOREACH(certs, authority_cert_t *, c, connection_write_to_buf_compress(