commit faf45800611a35be6a4e1381818e69852877f62e Author: Nick Mathewson nickm@torproject.org Date: Mon Jun 11 16:14:57 2018 -0400

Several attempts to diagnose ticket 25686

There are a few reasons that relays might be uploading desciptors without saying X-Desc-Gen-Reason: 1. They are running an old version of our software, before 0.3.2.stable. 2. They are not running our software, but they are claiming they are. 3. They are uploading through a proxy that strips X-Desc-Gen-Reason. 4. They somehow had a bug in their software.

According to the 25686 data, 1 is the most common reason. This ticket is an attempt to diagnose case 4, or prove that case 4 doesn't actually happen. --- changes/bug25686_diagnostic | 4 ++++ src/or/directory.c | 5 +++-- src/or/router.c | 8 +++++++- 3 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/changes/bug25686_diagnostic b/changes/bug25686_diagnostic new file mode 100644 index 000000000..96323145d --- /dev/null +++ b/changes/bug25686_diagnostic @@ -0,0 +1,4 @@ + o Minor features (relay, diagnostic): + - Add several checks to detect whether Tor relays are uploading their + descriptors without specifying why they regenerated. Diagnostic for + ticket 25686. diff --git a/src/or/directory.c b/src/or/directory.c index f14bdde90..47058352f 100644 --- a/src/or/directory.c +++ b/src/or/directory.c @@ -1810,9 +1810,10 @@ directory_send_command(dir_connection_t *conn, tor_assert(payload); httpcommand = "POST"; url = tor_strdup("/tor/"); - if (why) { - smartlist_add_asprintf(headers, "X-Desc-Gen-Reason: %s\r\n", why); + if (!why) { + why = "for no reason at all"; } + smartlist_add_asprintf(headers, "X-Desc-Gen-Reason: %s\r\n", why); break; } case DIR_PURPOSE_UPLOAD_VOTE: diff --git a/src/or/router.c b/src/or/router.c index 83e5538a5..cacd1132a 100644 --- a/src/or/router.c +++ b/src/or/router.c @@ -1866,7 +1866,7 @@ static routerinfo_t *desc_routerinfo = NULL; static extrainfo_t *desc_extrainfo = NULL; /** Why did we most recently decide to regenerate our descriptor? Used to * tell the authorities why we're sending it to them. */ -static const char *desc_gen_reason = NULL; +static const char *desc_gen_reason = "uninitialized reason"; /** Since when has our descriptor been "clean"? 0 if we need to regenerate it * now. */ static time_t desc_clean_since = 0; @@ -2454,6 +2454,9 @@ router_rebuild_descriptor(int force) desc_clean_since = time(NULL); desc_needs_upload = 1; desc_gen_reason = desc_dirty_reason; + if (BUG(desc_gen_reason == NULL)) { + desc_gen_reason = "descriptor was marked dirty earlier, for no reason."; + } desc_dirty_reason = NULL; control_event_my_descriptor_changed(); return 0; @@ -2510,6 +2513,9 @@ void mark_my_descriptor_dirty(const char *reason) { const or_options_t *options = get_options(); + if (BUG(reason == NULL)) { + reason = "marked descriptor dirty for unspecified reason"; + } if (server_mode(options) && options->PublishServerDescriptor_) log_info(LD_OR, "Decided to publish new relay descriptor: %s", reason); desc_clean_since = 0;