From af8cadf3a9febe3dbe22899b828f9f7946a82cef Mon Sep 17 00:00:00 2001 From: Roger Dingledine Date: Mon, 15 Jan 2018 22:33:40 -0500 Subject: [PATCH] Remove false positives from channel_is_client() Fix a set of false positives where relays would consider connections to other relays as being client-only connections (and thus e.g. deserving different link padding schemes) if those relays fell out of the consensus briefly. Now we look only at the initial handshake and whether the connection authenticated as a relay. Fixes bug 24898; bugfix on 0.3.1.1-alpha. --- changes/bug24898 | 8 ++++++++ src/or/command.c | 6 ------ src/or/connection_or.c | 6 ++++++ 3 files changed, 14 insertions(+), 6 deletions(-) create mode 100644 changes/bug24898 diff --git a/changes/bug24898 b/changes/bug24898 new file mode 100644 index 000000000..f64340d71 --- /dev/null +++ b/changes/bug24898 @@ -0,0 +1,8 @@ + o Major bugfixes (relays): + - Fix a set of false positives where relays would consider connections + to other relays as being client-only connections (and thus e.g. + deserving different link padding schemes) if those relays fell out + of the consensus briefly. Now we look only at the initial handshake + and whether the connection authenticated as a relay. Fixes bug + 24898; bugfix on 0.3.1.1-alpha. + diff --git a/src/or/command.c b/src/or/command.c index c667cbbe5..894483e00 100644 --- a/src/or/command.c +++ b/src/or/command.c @@ -328,12 +328,6 @@ command_process_create_cell(cell_t *cell, channel_t *chan) if (connection_or_digest_is_known_relay(chan->identity_digest)) { rep_hist_note_circuit_handshake_requested(create_cell->handshake_type); - // Needed for chutney: Sometimes relays aren't in the consensus yet, and - // get marked as clients. This resets their channels once they appear. - // Probably useful for normal operation wrt relay flapping, too. - chan->is_client = 0; - } else { - channel_mark_client(chan); } if (create_cell->handshake_type != ONION_HANDSHAKE_TYPE_FAST) { diff --git a/src/or/connection_or.c b/src/or/connection_or.c index 59a9bdffd..fcd281da2 100644 --- a/src/or/connection_or.c +++ b/src/or/connection_or.c @@ -1952,6 +1952,12 @@ connection_or_set_state_open(or_connection_t *conn) connection_or_change_state(conn, OR_CONN_STATE_OPEN); control_event_or_conn_status(conn, OR_CONN_EVENT_CONNECTED, 0); + /* Link protocol 3 appeared in Tor 0.2.3.6-alpha, so any connection + * that uses an earlier link protocol should not be treated as a relay. */ + if (conn->link_proto < 3) { + channel_mark_client(TLS_CHAN_TO_BASE(conn->chan)); + } + or_handshake_state_free(conn->handshake_state); conn->handshake_state = NULL; connection_start_reading(TO_CONN(conn));