commit 782eb02b79363bf8ed609495d516bc59972f4352 Author: Nick Mathewson nickm@torproject.org Date: Tue Jun 20 11:26:51 2017 -0400
Send the correct content-encoding when serving cached_dir_t objects
A cached_dir_t object (for now) is always compressed with DEFLATE_METHOD, but in handle_get_status_vote() to we were using the general compression-negotiation code decide what compression to claim we were using.
This was one of the reasons behind 22502.
Fixes bug 22669; bugfix on 0.3.1.1-alpha --- changes/bug22669 | 4 ++++ src/or/directory.c | 25 +++++++++++++++++++++++-- 2 files changed, 27 insertions(+), 2 deletions(-)
diff --git a/changes/bug22669 b/changes/bug22669 new file mode 100644 index 0000000..804a39e --- /dev/null +++ b/changes/bug22669 @@ -0,0 +1,4 @@ + o Minor bugfixes (compression): + - When serving directory votes compressed with zlib, + do not claim to have compressed them with zstd. Fixes bug 22669; + bugfix on 0.3.1.1-alpha. diff --git a/src/or/directory.c b/src/or/directory.c index ecd9811..b680b13 100644 --- a/src/or/directory.c +++ b/src/or/directory.c @@ -4190,13 +4190,14 @@ static int handle_get_status_vote(dir_connection_t *conn, const get_handler_args_t *args) { const char *url = args->url; - const compress_method_t compress_method = - find_best_compression_method(args->compression_supported, 1); { int current; ssize_t body_len = 0; ssize_t estimated_len = 0; + /* This smartlist holds strings that we can compress on the fly. */ smartlist_t *items = smartlist_new(); + /* This smartlist holds cached_dir_t objects that have a precompressed + * deflated version. */ smartlist_t *dir_items = smartlist_new(); int lifetime = 60; /* XXXX?? should actually use vote intervals. */ url += strlen("/tor/status-vote/"); @@ -4247,6 +4248,26 @@ handle_get_status_vote(dir_connection_t *conn, const get_handler_args_t *args) write_http_status_line(conn, 404, "Not found"); goto vote_done; } + + /* We're sending items from at most one kind of source */ + tor_assert_nonfatal(smartlist_len(items) == 0 || + smartlist_len(dir_items) == 0); + + int streaming; + unsigned mask; + if (smartlist_len(items)) { + /* We're taking strings and compressing them on the fly. */ + streaming = 1; + mask = ~0u; + } else { + /* We're taking cached_dir_t objects. We only have them uncompressed + * or deflated. */ + streaming = 0; + mask = (1u<<NO_METHOD) | (1u<<ZLIB_METHOD); + } + const compress_method_t compress_method = find_best_compression_method( + args->compression_supported&mask, streaming); + SMARTLIST_FOREACH(dir_items, cached_dir_t *, d, body_len += compress_method != NO_METHOD ? d->dir_compressed_len : d->dir_len);