From 2b63fa40e8349e0e6c40d0660d9df5b0ba73937e Mon Sep 17 00:00:00 2001 From: Roger Dingledine Date: Mon, 27 Jul 2009 21:01:24 -0400 Subject: three hacks to workaround bug 1038 The problem is that clients and hidden services are receiving relay_early cells, and they tear down the circuit. Hack #1 is for rendezvous points to rewrite relay_early cells to relay cells. That way there are never any incoming relay_early cells. Hack #2 is for clients and hidden services to never send a relay_early cell on an established rendezvous circuit. That works around rendezvous points that haven't upgraded yet. Hack #3 is for clients and hidden services to not tear down the circuit when they receive an inbound relay_early cell. We already refuse extend cells at clients. --- src/or/relay.c | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-) (limited to 'src/or/relay.c') diff --git a/src/or/relay.c b/src/or/relay.c index 8099f4f072..3419e3d190 100644 --- a/src/or/relay.c +++ b/src/or/relay.c @@ -208,6 +208,7 @@ circuit_receive_relay_cell(cell_t *cell, circuit_t *circ, tor_assert(circ->purpose == CIRCUIT_PURPOSE_REND_ESTABLISHED); tor_assert(splice->_base.purpose == CIRCUIT_PURPOSE_REND_ESTABLISHED); cell->circ_id = splice->p_circ_id; + cell->command = CELL_RELAY; /* can't be relay_early anyway */ if ((reason = circuit_receive_relay_cell(cell, TO_CIRCUIT(splice), CELL_DIRECTION_IN)) < 0) { log_warn(LD_REND, "Error relaying cell across rendezvous; closing " @@ -541,11 +542,17 @@ relay_send_command_from_edge(uint16_t stream_id, circuit_t *circ, origin_circuit_t *origin_circ = TO_ORIGIN_CIRCUIT(circ); if (origin_circ->remaining_relay_early_cells > 0 && (relay_command == RELAY_COMMAND_EXTEND || - cpath_layer != origin_circ->cpath)) { - /* If we've got any relay_early cells left, and we're sending a relay - * cell or we're not talking to the first hop, use one of them. Don't - * worry about the conn protocol version: append_cell_to_circuit_queue - * will fix it up. */ + (cpath_layer != origin_circ->cpath && + !CIRCUIT_PURPOSE_IS_ESTABLISHED_REND(circ->purpose)))) { + /* If we've got any relay_early cells left, and we're sending + * an extend cell or (we're not talking to the first hop and we're + * not talking to a rendezvous circuit), use one of them. + * Don't worry about the conn protocol version: + * append_cell_to_circuit_queue will fix it up. */ + /* XXX For now, clients don't use RELAY_EARLY cells when sending + * relay cells on rendezvous circuits. See bug 1038. Eventually, + * we can take this behavior away in favor of having clients avoid + * rendezvous points running 0.2.1.3-alpha through 0.2.1.18. -RD */ cell.command = CELL_RELAY_EARLY; --origin_circ->remaining_relay_early_cells; log_debug(LD_OR, "Sending a RELAY_EARLY cell; %d remaining.", -- cgit v1.2.3-54-g00ecf