prop224: Pick rendezvous point of protover HSRend=2 (c527cde8) · Commits · David Goulet / Tor

src/or/circuitbuild.c

+22 −6

Original line number	Diff line number	Diff line
		@@ -71,7 +71,8 @@ static channel_t * channel_connect_for_circuit(const tor_addr_t *addr,
		static int circuit_deliver_create_cell(circuit_t *circ,
		const create_cell_t *create_cell,
		int relayed);
		static int onion_pick_cpath_exit(origin_circuit_t circ, extend_info_t exit);
		static int onion_pick_cpath_exit(origin_circuit_t circ, extend_info_t exit,
		int is_hs_v3_rp_circuit);
		static crypt_path_t onion_next_hop_in_cpath(crypt_path_t cpath);
		static int onion_extend_cpath(origin_circuit_t *circ);
		static int onion_append_hop(crypt_path_t *head_ptr, extend_info_t choice);
		@@ -505,10 +506,15 @@ circuit_establish_circuit(uint8_t purpose, extend_info_t *exit_ei, int flags)
		{
		origin_circuit_t *circ;
		int err_reason = 0;
		int is_hs_v3_rp_circuit = 0;

		if (flags & CIRCLAUNCH_IS_V3_RP) {
		is_hs_v3_rp_circuit = 1;
		}

		circ = origin_circuit_init(purpose, flags);

		if (onion_pick_cpath_exit(circ, exit_ei) < 0 \|\|
		if (onion_pick_cpath_exit(circ, exit_ei, is_hs_v3_rp_circuit) < 0 \|\|
		onion_populate_cpath(circ) < 0) {
		circuit_mark_for_close(TO_CIRCUIT(circ), END_CIRC_REASON_NOPATH);
		return NULL;
		@@ -2156,7 +2162,8 @@ pick_rendezvous_node(router_crn_flags_t flags)
		*/
		static const node_t *
		choose_good_exit_server(uint8_t purpose,
		int need_uptime, int need_capacity, int is_internal)
		int need_uptime, int need_capacity, int is_internal,
		int need_hs_v3)
		{
		const or_options_t *options = get_options();
		router_crn_flags_t flags = CRN_NEED_DESC;
		@@ -2164,6 +2171,8 @@ choose_good_exit_server(uint8_t purpose,
		flags \|= CRN_NEED_UPTIME;
		if (need_capacity)
		flags \|= CRN_NEED_CAPACITY;
		if (need_hs_v3)
		flags \|= CRN_RENDEZVOUS_V3;

		switch (purpose) {
		case CIRCUIT_PURPOSE_C_GENERAL:
		@@ -2263,9 +2272,15 @@ warn_if_last_router_excluded(origin_circuit_t *circ,

		/** Decide a suitable length for circ's cpath, and pick an exit
		* router (or use <b>exit</b> if provided). Store these in the
		* cpath. Return 0 if ok, -1 if circuit should be closed. */
		* cpath.
		*
		* If <b>is_hs_v3_rp_circuit</b> is set, then this exit should be suitable to
		* be used as an HS v3 rendezvous point.
		*
		* Return 0 if ok, -1 if circuit should be closed. */
		static int
		onion_pick_cpath_exit(origin_circuit_t circ, extend_info_t exit_ei)
		onion_pick_cpath_exit(origin_circuit_t circ, extend_info_t exit_ei,
		int is_hs_v3_rp_circuit)
		{
		cpath_build_state_t *state = circ->build_state;

		@@ -2289,7 +2304,8 @@ onion_pick_cpath_exit(origin_circuit_t circ, extend_info_t exit_ei)
		} else { /* we have to decide one */
		const node_t *node =
		choose_good_exit_server(circ->base_.purpose, state->need_uptime,
		state->need_capacity, state->is_internal);
		state->need_capacity, state->is_internal,
		is_hs_v3_rp_circuit);
		if (!node) {
		log_warn(LD_CIRC,"Failed to choose an exit server");
		return -1;

src/or/circuitlist.c

+32 −0

Original line number	Diff line number	Diff line
		@@ -1609,6 +1609,30 @@ circuit_get_next_by_pk_and_purpose(origin_circuit_t *start,
		return NULL;
		}

		/** We might cannibalize this circuit: Return true if its last hop can be used
		* as a v3 rendezvous point. */
		static int
		circuit_can_be_cannibalized_for_v3_rp(const origin_circuit_t *circ)
		{
		if (!circ->build_state) {
		return 0;
		}

		extend_info_t *chosen_exit = circ->build_state->chosen_exit;
		if (BUG(!chosen_exit)) {
		return 0;
		}

		const node_t *rp_node = node_get_by_id(chosen_exit->identity_digest);
		if (rp_node) {
		if (node_supports_v3_rendezvous_point(rp_node)) {
		return 1;
		}
		}

		return 0;
		}

		/** Return a circuit that is open, is CIRCUIT_PURPOSE_C_GENERAL,
		* has a timestamp_dirty value of 0, has flags matching the CIRCLAUNCH_*
		* flags in <b>flags</b>, and if info is defined, does not already use info
		@@ -1691,6 +1715,14 @@ circuit_find_to_cannibalize(uint8_t purpose, extend_info_t *info,
		hop = hop->next;
		} while (hop != circ->cpath);
		}

		if ((flags & CIRCLAUNCH_IS_V3_RP) &&
		!circuit_can_be_cannibalized_for_v3_rp(circ)) {
		log_debug(LD_GENERAL, "Skipping uncannibalizable circuit for v3 "
		"rendezvous point.");
		goto next;
		}

		if (!best \|\| (best->build_state->need_uptime && !need_uptime))
		best = circ;
		next: ;

src/or/circuituse.c

+10 −0

Original line number	Diff line number	Diff line
		@@ -2290,6 +2290,16 @@ circuit_get_open_circ_or_launch(entry_connection_t *conn,
		if (want_onehop) flags \|= CIRCLAUNCH_ONEHOP_TUNNEL;
		if (need_uptime) flags \|= CIRCLAUNCH_NEED_UPTIME;
		if (need_internal) flags \|= CIRCLAUNCH_IS_INTERNAL;

		/* If we are about to pick a v3 RP right now, make sure we pick a
		* rendezvous point that supports the v3 protocol! */
		if (desired_circuit_purpose == CIRCUIT_PURPOSE_C_REND_JOINED &&
		new_circ_purpose == CIRCUIT_PURPOSE_C_ESTABLISH_REND &&
		ENTRY_TO_EDGE_CONN(conn)->hs_ident) {
		flags \|= CIRCLAUNCH_IS_V3_RP;
		log_info(LD_GENERAL, "Getting rendezvous circuit to v3 service!");
		}

		circ = circuit_launch_by_extend_info(new_circ_purpose, extend_info,
		flags);
		}

src/or/circuituse.h

+3 −0

Original line number	Diff line number	Diff line
		@@ -44,6 +44,9 @@ void circuit_build_failed(origin_circuit_t *circ);
		/** Flag to set when the last hop of a circuit doesn't need to be an
		* exit node. */
		#define CIRCLAUNCH_IS_INTERNAL (1<<3)
		/** Flag to set when we are trying to launch a v3 rendezvous circuit. We need
		* to apply some additional filters on the node picked. */
		#define CIRCLAUNCH_IS_V3_RP (1<<4)
		origin_circuit_t *circuit_launch_by_extend_info(uint8_t purpose,
		extend_info_t *info,
		int flags);

src/or/hs_client.c

+15 −2

Original line number	Diff line number	Diff line
		@@ -24,6 +24,7 @@
		#include "circuitlist.h"
		#include "circuituse.h"
		#include "connection.h"
		#include "nodelist.h"
		#include "circpathbias.h"
		#include "connection.h"
		#include "hs_ntor.h"
		@@ -461,9 +462,21 @@ client_rendezvous_circ_has_opened(origin_circuit_t *circ)
		tor_assert(circ);
		tor_assert(TO_CIRCUIT(circ)->purpose == CIRCUIT_PURPOSE_C_ESTABLISH_REND);

		const extend_info_t *rp_ei = circ->build_state->chosen_exit;

		/* Check that we didn't accidentally choose a node that does not understand
		* the v3 rendezvous protocol */
		if (rp_ei) {
		const node_t *rp_node = node_get_by_id(rp_ei->identity_digest);
		if (rp_node) {
		if (BUG(!node_supports_v3_rendezvous_point(rp_node))) {
		return;
		}
		}
		}

		log_info(LD_REND, "Rendezvous circuit has opened to %s.",
		safe_str_client(
		extend_info_describe(circ->build_state->chosen_exit)));
		safe_str_client(extend_info_describe(rp_ei)));

		/* Ignore returned value, nothing we can really do. On failure, the circuit
		* will be marked for close. */