commit f2b1eb1f052c99e0be096b98888e9854cf57a64c Author: David Goulet dgoulet@torproject.org Date: Wed Jun 19 11:09:14 2019 -0400

hs: Disallow single hop client circuit when introducing

This will effectively also deny any bridge to be used as a single hop to the introduction point since bridge do not authenticate like clients.

Fixes #24963

Signed-off-by: David Goulet dgoulet@torproject.org --- changes/ticket24963 | 5 +++++ src/feature/hs/hs_intropoint.c | 9 +++++++++ 2 files changed, 14 insertions(+)

diff --git a/changes/ticket24963 b/changes/ticket24963 new file mode 100644 index 000000000..50adcfaaf --- /dev/null +++ b/changes/ticket24963 @@ -0,0 +1,5 @@ + o Minor feature (onion service): + - Disallow single hop clients to introduce directly at the introduction + point. We've removed Tor2web a while back and rendezvous are blocked at + the relays. This is to remove load off the network from spammy clients. + Close ticket 24963. diff --git a/src/feature/hs/hs_intropoint.c b/src/feature/hs/hs_intropoint.c index 9333060e7..447f73b60 100644 --- a/src/feature/hs/hs_intropoint.c +++ b/src/feature/hs/hs_intropoint.c @@ -10,6 +10,7 @@

#include "core/or/or.h" #include "app/config/config.h" +#include "core/or/channel.h" #include "core/or/circuitlist.h" #include "core/or/circuituse.h" #include "core/or/relay.h" @@ -546,6 +547,14 @@ circuit_is_suitable_for_introduce1(const or_circuit_t *circ) return 0; }

+ /* Disallow single hop client circuit. */ + if (channel_is_client(circ->p_chan)) { + log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL, + "Single hop client was rejected while trying to introduce. " + "Closing circuit."); + return 0; + } + return 1; }