Hook up client usage of congestion control negotiation (76bdadce) · Commits · The Tor Project / Core / Tor

src/core/or/circuitbuild.c

+43 −9

Original line number	Diff line number	Diff line
		@@ -72,6 +72,7 @@
		#include "feature/stats/predict_ports.h"
		#include "lib/crypt_ops/crypto_rand.h"
		#include "lib/trace/events.h"
		#include "core/or/congestion_control_common.h"

		#include "core/or/cell_st.h"
		#include "core/or/cpath_build_state_st.h"
		@@ -80,6 +81,7 @@
		#include "feature/nodelist/node_st.h"
		#include "core/or/or_circuit_st.h"
		#include "core/or/origin_circuit_st.h"
		#include "trunnel/circ_params.h"

		static int circuit_send_first_onion_skin(origin_circuit_t *circ);
		static int circuit_build_no_more_hops(origin_circuit_t *circ);
		@@ -841,7 +843,10 @@ circuit_pick_create_handshake(uint8_t *cell_type_out,
		* using the TAP handshake, and CREATE2 otherwise. */
		if (extend_info_supports_ntor(ei)) {
		*cell_type_out = CELL_CREATE2;
		if (ei->supports_ntor3_and_param_negotiation)
		/* Only use ntor v3 with exits that support congestion control,
		* and only when it is enabled. */
		if (ei->exit_supports_congestion_control &&
		congestion_control_enabled())
		*handshake_type_out = ONION_HANDSHAKE_TYPE_NTOR_V3;
		else
		*handshake_type_out = ONION_HANDSHAKE_TYPE_NTOR;
		@@ -1263,12 +1268,14 @@ circuit_finish_handshake(origin_circuit_t *circ,

		onion_handshake_state_release(&hop->handshake_state);

		// XXXX TODO-324: use `params` to initialize the congestion control.

		if (cpath_init_circuit_crypto(hop, keys, sizeof(keys), 0, 0)<0) {
		return -END_CIRC_REASON_TORPROTOCOL;
		}

		if (params.cc_enabled) {
		hop->ccontrol = congestion_control_new(&params);
		}

		hop->state = CPATH_STATE_OPEN;
		log_info(LD_CIRC,"Finished building circuit hop:");
		circuit_log_path(LOG_INFO,LD_CIRC,circ);
		@@ -2068,7 +2075,10 @@ onion_pick_cpath_exit(origin_circuit_t circ, extend_info_t exit_ei,
		log_warn(LD_CIRC,"Failed to choose an exit server");
		return -1;
		}
		exit_ei = extend_info_from_node(node, state->onehop_tunnel);
		exit_ei = extend_info_from_node(node, state->onehop_tunnel,
		/* for_exit_use */
		!state->is_internal && TO_CIRCUIT(circ)->purpose ==
		CIRCUIT_PURPOSE_C_GENERAL);
		if (BUG(exit_ei == NULL))
		return -1;
		}
		@@ -2464,7 +2474,7 @@ onion_extend_cpath(origin_circuit_t *circ)
		primary address, for potentially connecting to an IPv6 OR
		port. Servers always want the primary (IPv4) address. */
		int client = (server_mode(get_options()) == 0);
		info = extend_info_from_node(r, client);
		info = extend_info_from_node(r, client, false);
		/* Clients can fail to find an allowed address */
		tor_assert_nonfatal(info \|\| client);
		}
		@@ -2472,7 +2482,7 @@ onion_extend_cpath(origin_circuit_t *circ)
		const node_t *r =
		choose_good_middle_server(purpose, state, circ->cpath, cur_len);
		if (r) {
		info = extend_info_from_node(r, 0);
		info = extend_info_from_node(r, 0, false);
		}
		}

		@@ -2597,9 +2607,33 @@ client_circ_negotiation_message(const extend_info_t *ei,
		size_t *msg_len_out)
		{
		tor_assert(ei && msg_out && msg_len_out);
		if (! ei->supports_ntor3_and_param_negotiation)
		circ_params_request_t params = {0};
		ssize_t msg_len = 0;

		if (! ei->exit_supports_congestion_control)
		return -1;

		/* TODO-324: fill in the client message that gets sent. */
		tor_assert_unreached();
		circ_params_request_set_version(&params, 0);

		circ_params_request_set_cc_supported(&params,
		congestion_control_enabled());

		msg_len = circ_params_request_encoded_len(&params);

		if (msg_len < 0) {
		return -1;
		}

		*msg_out = tor_malloc_zero(msg_len);

		msg_len = circ_params_request_encode(*msg_out, msg_len, &params);

		if (msg_len < 0) {
		tor_free(*msg_out);
		return -1;
		}

		*msg_len_out = (size_t)msg_len;

		return 0;
		}

src/core/or/circuituse.c

+4 −2

Original line number	Diff line number	Diff line
		@@ -2427,7 +2427,8 @@ circuit_get_open_circ_or_launch(entry_connection_t *conn,
		/* We might want to connect to an IPv6 bridge for loading
		descriptors so we use the preferred address rather than
		the primary. */
		extend_info = extend_info_from_node(r, conn->want_onehop ? 1 : 0);
		extend_info = extend_info_from_node(r, conn->want_onehop ? 1 : 0,
		desired_circuit_purpose == CIRCUIT_PURPOSE_C_GENERAL);
		if (!extend_info) {
		log_warn(LD_CIRC,"Could not make a one-hop connection to %s. "
		"Discarding this circuit.", conn->chosen_exit_name);
		@@ -2463,7 +2464,8 @@ circuit_get_open_circ_or_launch(entry_connection_t *conn,
		NULL, /* Ed25519 ID */
		NULL, NULL, /* onion keys */
		&addr, conn->socks_request->port,
		NULL);
		NULL,
		false);
		} else { /* ! (want_onehop && conn->chosen_exit_name[0] == '$') */
		/* We will need an onion key for the router, and we
		* don't have one. Refuse or relax requirements. */

src/core/or/command.c

+1 −3

Original line number	Diff line number	Diff line
		@@ -367,6 +367,7 @@ command_process_create_cell(cell_t cell, channel_t chan)
		create_cell->onionskin,
		create_cell->handshake_len,
		NULL,
		NULL,
		created_cell.reply,
		sizeof(created_cell.reply),
		keys, CPATH_KEY_MATERIAL_LEN,
		@@ -381,9 +382,6 @@ command_process_create_cell(cell_t cell, channel_t chan)
		created_cell.cell_type = CELL_CREATED_FAST;
		created_cell.handshake_len = len;

		// TODO-324: We should in theory look at params here, though it will
		// always tell us to use the old-fashioned congestion control.

		if (onionskin_answer(circ, &created_cell,
		(const char *)keys, sizeof(keys),
		rend_circ_nonce)<0) {

src/core/or/extend_info_st.h

+4 −3

Original line number	Diff line number	Diff line
		@@ -38,9 +38,10 @@ struct extend_info_t {
		crypto_pk_t *onion_key;
		/** Ntor onion key for this hop. */
		curve25519_public_key_t curve25519_onion_key;
		/** True if this hop supports NtorV3 _and_ negotiation of at least one
		* relevant circuit parameter (currently only congestion control). */
		bool supports_ntor3_and_param_negotiation;
		/** True if this hop is to be used as an _exit_,
		* and it also supports supports NtorV3 _and_ negotiation
		* of congestion control parameters */
		bool exit_supports_congestion_control;
		};

		#endif /* !defined(EXTEND_INFO_ST_H) */

src/core/or/extendinfo.c

+12 −8

Original line number	Diff line number	Diff line
		@@ -36,7 +36,8 @@ extend_info_new(const char *nickname,
		crypto_pk_t *onion_key,
		const curve25519_public_key_t *ntor_key,
		const tor_addr_t *addr, uint16_t port,
		const protover_summary_flags_t *pv)
		const protover_summary_flags_t *pv,
		bool for_exit_use)
		{
		extend_info_t *info = tor_malloc_zero(sizeof(extend_info_t));
		if (rsa_id_digest)
		@@ -58,9 +59,9 @@ extend_info_new(const char *nickname,
		extend_info_add_orport(info, addr, port);
		}

		if (pv) {
		info->supports_ntor3_and_param_negotiation =
		pv->supports_ntor3_and_param_negotiation;
		if (pv && for_exit_use) {
		info->exit_supports_congestion_control =
		pv->supports_congestion_control;
		}

		return info;
		@@ -96,7 +97,8 @@ extend_info_add_orport(extend_info_t *ei,
		* and IP version config.
		**/
		extend_info_t *
		extend_info_from_node(const node_t *node, int for_direct_connect)
		extend_info_from_node(const node_t *node, int for_direct_connect,
		bool for_exit)
		{
		crypto_pk_t *rsa_pubkey = NULL;
		extend_info_t *info = NULL;
		@@ -157,7 +159,8 @@ extend_info_from_node(const node_t *node, int for_direct_connect)
		curve_pubkey,
		&ap.addr,
		ap.port,
		&node->ri->pv);
		&node->ri->pv,
		for_exit);
		} else if (valid_addr && node->rs && node->md) {
		info = extend_info_new(node->rs->nickname,
		node->identity,
		@@ -166,7 +169,8 @@ extend_info_from_node(const node_t *node, int for_direct_connect)
		curve_pubkey,
		&ap.addr,
		ap.port,
		&node->rs->pv);
		&node->rs->pv,
		for_exit);
		}

		crypto_pk_free(rsa_pubkey);
		@@ -225,7 +229,7 @@ extend_info_supports_ntor_v3(const extend_info_t *ei)
		{
		tor_assert(ei);
		return extend_info_supports_ntor(ei) &&
		ei->supports_ntor3_and_param_negotiation;
		ei->exit_supports_congestion_control;
		}

		/* Does ei have an onion key which it would prefer to use?