From 130e899fbb02d6005e3797dea2099e4033345ebe Mon Sep 17 00:00:00 2001 From: Robert Ransom Date: Tue, 18 Sep 2012 16:50:00 -0400 Subject: [PATCH] Warn if HSes are configured on a client with UseEntryGuards disabled --- changes/warn-about-hses-without-guards | 8 ++++++++ src/or/config.c | 9 +++++++++ 2 files changed, 17 insertions(+) create mode 100644 changes/warn-about-hses-without-guards diff --git a/changes/warn-about-hses-without-guards b/changes/warn-about-hses-without-guards new file mode 100644 index 0000000000..57b8b4d00f --- /dev/null +++ b/changes/warn-about-hses-without-guards @@ -0,0 +1,8 @@ + o Minor features: + + - Warn users who run hidden services on a Tor client with + UseEntryGuards disabled that their hidden services will be + vulnerable to http://freehaven.net/anonbib/#hs-attack06 (the + attack which motivated Tor to support entry guards in the first + place). Fixes bug 6889. + diff --git a/src/or/config.c b/src/or/config.c index affe2388bf..11f63efddc 100644 --- a/src/or/config.c +++ b/src/or/config.c @@ -2536,6 +2536,15 @@ options_validate(or_options_t *old_options, or_options_t *options, options->UseEntryGuards = 0; } + if (!(options->UseEntryGuards) && + (options->RendConfigLines != NULL)) { + log_warn(LD_CONFIG, + "UseEntryGuards is disabled, but you have configured one or more " + "hidden services on this Tor instance. Your hidden services " + "will be very easy to locate using a well-known attack -- see " + "http://freehaven.net/anonbib/#hs-attack06 for details."); + } + if (!(options->LearnCircuitBuildTimeout) && options->CircuitBuildTimeout < RECOMMENDED_MIN_CIRCUIT_BUILD_TIMEOUT) { log_warn(LD_CONFIG,