commit 44db455cc894b4a0fda80a28ed5ea55bf4d41231 Author: teor teor@torproject.org Date: Thu Nov 29 01:03:03 2018 +1000
Dir: allow directory mirrors to serve future consensuses
When Tor's clock is behind the clocks on the authorities, allow Tor to serve future consensuses.
Fixes bug 28654; bugfix on 0.3.0.1-alpha. --- changes/bug28654 | 3 ++ src/feature/dircache/dircache.c | 73 ++++++++++++++++++++++++++++------------- 2 files changed, 54 insertions(+), 22 deletions(-)
diff --git a/changes/bug28654 b/changes/bug28654 new file mode 100644 index 000000000..4ca843309 --- /dev/null +++ b/changes/bug28654 @@ -0,0 +1,3 @@ + o Minor bugfixes (directory mirror): + - When Tor's clock is behind the clocks on the authorities, allow Tor to + serve future consensuses. Fixes bug 28654; bugfix on 0.3.0.1-alpha. diff --git a/src/feature/dircache/dircache.c b/src/feature/dircache/dircache.c index 872a88018..ce90f4910 100644 --- a/src/feature/dircache/dircache.c +++ b/src/feature/dircache/dircache.c @@ -495,28 +495,47 @@ handle_get_frontpage(dir_connection_t *conn, const get_handler_args_t *args) }
/** Warn that the cached consensus <b>consensus</b> of type - * <b>flavor</b> is too old and will not be served to clients. Rate-limit the - * warning to avoid logging an entry on every request. + * <b>flavor</b> too new or too old, based on <b>is_too_new</b>, + * and will not be served to clients. Rate-limit the warning to avoid logging + * an entry on every request. */ static void -warn_consensus_is_too_old(const struct consensus_cache_entry_t *consensus, - const char *flavor, time_t now) +warn_consensus_is_not_reasonably_live( + const struct consensus_cache_entry_t *consensus, + const char *flavor, time_t now, bool is_too_new) { -#define TOO_OLD_WARNING_INTERVAL (60*60) - static ratelim_t warned = RATELIM_INIT(TOO_OLD_WARNING_INTERVAL); +#define NOT_REASONABLY_LIVE_WARNING_INTERVAL (60*60) + static ratelim_t warned[2] = { RATELIM_INIT( + NOT_REASONABLY_LIVE_WARNING_INTERVAL), + RATELIM_INIT( + NOT_REASONABLY_LIVE_WARNING_INTERVAL) }; char timestamp[ISO_TIME_LEN+1]; - time_t valid_until; - char *dupes; + /* valid_after if is_too_new, valid_until if !is_too_new */ + time_t valid_time = 0; + char *dupes = NULL;
- if (consensus_cache_entry_get_valid_until(consensus, &valid_until)) - return; - - if ((dupes = rate_limit_log(&warned, now))) { - format_local_iso_time(timestamp, valid_until); - log_warn(LD_DIRSERV, "Our %s%sconsensus is too old, so we will not " - "serve it to clients. It was valid until %s local time and we " - "continued to serve it for up to 24 hours after it expired.%s", - flavor ? flavor : "", flavor ? " " : "", timestamp, dupes); + if (is_too_new) { + if (consensus_cache_entry_get_valid_after(consensus, &valid_time)) + return; + dupes = rate_limit_log(&warned[1], now); + } else { + if (consensus_cache_entry_get_valid_until(consensus, &valid_time)) + return; + dupes = rate_limit_log(&warned[0], now); + } + + if (dupes) { + format_local_iso_time(timestamp, valid_time); + log_warn(LD_DIRSERV, "Our %s%sconsensus is too %s, so we will not " + "serve it to clients. It was valid %s %s local time and we " + "continued to serve it for up to 24 hours %s.%s", + flavor ? flavor : "", + flavor ? " " : "", + is_too_new ? "new" : "old", + is_too_new ? "after" : "until", + timestamp, + is_too_new ? "before it was valid" : "after it expired", + dupes); tor_free(dupes); } } @@ -859,7 +878,6 @@ handle_get_current_consensus(dir_connection_t *conn,
if (req.diff_only && !cached_consensus) { write_short_http_response(conn, 404, "No such diff available"); - // XXXX warn_consensus_is_too_old(v, req.flavor, now); geoip_note_ns_response(GEOIP_REJECT_NOT_FOUND); goto done; } @@ -870,19 +888,30 @@ handle_get_current_consensus(dir_connection_t *conn, &compression_used); }
- time_t fresh_until, valid_until; - int have_fresh_until = 0, have_valid_until = 0; + time_t valid_after, fresh_until, valid_until; + int have_valid_after = 0, have_fresh_until = 0, have_valid_until = 0; if (cached_consensus) { + have_valid_after = + !consensus_cache_entry_get_valid_after(cached_consensus, &valid_after); have_fresh_until = !consensus_cache_entry_get_fresh_until(cached_consensus, &fresh_until); have_valid_until = !consensus_cache_entry_get_valid_until(cached_consensus, &valid_until); }
- if (cached_consensus && have_valid_until && + if (cached_consensus && have_valid_after && + !networkstatus_valid_after_is_reasonably_live(valid_after, now)) { + write_short_http_response(conn, 404, "Consensus is too new"); + warn_consensus_is_not_reasonably_live(cached_consensus, req.flavor, now, + 1); + geoip_note_ns_response(GEOIP_REJECT_NOT_FOUND); + goto done; + } else if ( + cached_consensus && have_valid_until && !networkstatus_valid_until_is_reasonably_live(valid_until, now)) { write_short_http_response(conn, 404, "Consensus is too old"); - warn_consensus_is_too_old(cached_consensus, req.flavor, now); + warn_consensus_is_not_reasonably_live(cached_consensus, req.flavor, now, + 0); geoip_note_ns_response(GEOIP_REJECT_NOT_FOUND); goto done; }