Implemented router twins (21478985) · Commits · Mike Perry / Tor

src/or/circuit.c

+4 −4

Original line number	Diff line number	Diff line
		@@ -287,14 +287,14 @@ int circuit_crypt(circuit_t circ, char in, size_t inlen, char crypt_type) {
		return -1;

		if(crypt_type == 'e') {
		log(LOG_DEBUG,"circuit_crypt(): Encrypting %d bytes.",inlen);
		// log(LOG_DEBUG,"circuit_crypt(): Encrypting %d bytes.",inlen);
		if(circ->cpath) { /* we're at the beginning of the circuit. We'll want to do layered crypts. */
		/* 'e' means we're preparing to send it out. */
		for (i=0; i < circ->cpathlen; i++) /* moving from last to first hop
		* Remember : cpath is in reverse order, i.e. last hop first
		*/
		{
		log(LOG_DEBUG,"circuit_crypt() : Encrypting via cpath: Processing hop %u",circ->cpathlen-i);
		// log(LOG_DEBUG,"circuit_crypt() : Encrypting via cpath: Processing hop %u",circ->cpathlen-i);
		thishop = circ->cpath[i];

		/* encrypt */
		@@ -317,13 +317,13 @@ int circuit_crypt(circuit_t circ, char in, size_t inlen, char crypt_type) {
		memcpy(in,out,inlen);
		}
		} else if(crypt_type == 'd') {
		log(LOG_DEBUG,"circuit_crypt(): Decrypting %d bytes.",inlen);
		// log(LOG_DEBUG,"circuit_crypt(): Decrypting %d bytes.",inlen);
		if(circ->cpath) { /* we're at the beginning of the circuit. We'll want to do layered crypts. */
		for (i=circ->cpathlen-1; i >= 0; i--) /* moving from first to last hop
		* Remember : cpath is in reverse order, i.e. last hop first
		*/
		{
		log(LOG_DEBUG,"circuit_crypt() : Decrypting via cpath: Processing hop %u",circ->cpathlen-i);
		// log(LOG_DEBUG,"circuit_crypt() : Decrypting via cpath: Processing hop %u",circ->cpathlen-i);
		thishop = circ->cpath[i];

		/* encrypt */

src/or/command.c

+4 −0

Original line number	Diff line number	Diff line
		@@ -111,6 +111,10 @@ void command_process_create_cell(cell_t cell, connection_t conn) {
		circuit_close(circ);
		return;
		}

		circ->n_addr = n_conn->addr; /* these are different if we found a twin instead */
		circ->n_port = n_conn->port;

		circ->n_conn = n_conn;
		log(LOG_DEBUG,"command_process_create_cell(): n_conn is %s:%u",n_conn->address,ntohs(n_conn->port));

src/or/connection_ap.c

+9 −7

Original line number	Diff line number	Diff line
		@@ -195,8 +195,6 @@ int ap_handshake_establish_circuit(connection_t conn, unsigned int route, int
		free(route); /* we don't need it anymore */

		circ = circuit_new(0, conn); /* sets circ->p_aci and circ->p_conn */
		circ->n_addr = firsthop->addr;
		circ->n_port = firsthop->or_port;
		circ->state = CIRCUIT_STATE_OR_WAIT;
		circ->onion = onion;
		circ->onionlen = onionlen;
		@@ -207,6 +205,8 @@ int ap_handshake_establish_circuit(connection_t conn, unsigned int route, int
		firsthop->address,ntohs(firsthop->or_port));
		n_conn = connection_twin_get_by_addr_port(firsthop->addr,firsthop->or_port);
		if(!n_conn) { /* not currently connected */
		circ->n_addr = firsthop->addr;
		circ->n_port = firsthop->or_port;
		if(global_role & ROLE_OR_CONNECT_ALL) { /* we would be connected if he were up. but he's not. */
		log(LOG_DEBUG,"ap_handshake_establish_circuit(): Route's firsthop isn't connected.");
		circuit_close(circ);
		@@ -221,11 +221,13 @@ int ap_handshake_establish_circuit(connection_t conn, unsigned int route, int
		return -1;
		}
		conn->state = AP_CONN_STATE_OR_WAIT;
		connection_watch_events(conn, 0); /* Stop listening for input from the AP! */
		connection_stop_reading(conn); /* Stop listening for input from the AP! */
		return 0; /* return success. The onion/circuit/etc will be taken care of automatically
		* (may already have been) whenever n_conn reaches OR_CONN_STATE_OPEN.
		*/
		} else { /* it's already open. use it. */
		} else { /* it (or a twin) is already open. use it. */
		circ->n_addr = n_conn->addr;
		circ->n_port = n_conn->port;
		return ap_handshake_send_onion(conn, n_conn, circ);
		}
		}
		@@ -237,12 +239,12 @@ int ap_handshake_n_conn_open(connection_t *or_conn) {
		log(LOG_DEBUG,"ap_handshake_n_conn_open(): Starting.");
		circ = circuit_get_by_naddr_nport(or_conn->addr, or_conn->port);
		if(!circ)
		return 0; /* i'm ok with that */
		return 0; /* i'm ok with that. no need to close the connection or anything. */

		if(circ->p_conn->state != AP_CONN_STATE_OR_WAIT) {
		log(LOG_DEBUG,"Bug: ap_handshake_n_conn_open() got an ap_conn not in OR_WAIT state.");
		}
		connection_watch_events(or_conn, POLLIN); /* resume listening for reads */
		connection_start_reading(circ->p_conn); /* resume listening for reads */
		log(LOG_DEBUG,"ap_handshake_n_conn_open(): Found circ, sending onion.");
		return ap_handshake_send_onion(circ->p_conn, or_conn, circ);
		}
		@@ -332,7 +334,7 @@ int ap_handshake_send_onion(connection_t ap_conn, connection_t n_conn, circuit

		/* now we want to give the AP a "0" byte, because it wants to hear
		* back from us */
		connection_write_to_buf(&zero, 1, ap_conn);
		connection_write_to_buf(&zero, 1, ap_conn); /* this does connection_start_writing() too */

		return 0;
		}

src/or/main.c

+30 −1

Original line number	Diff line number	Diff line
		@@ -91,6 +91,22 @@ int connection_remove(connection_t *conn) {
		return 0;
		}

		int pkey_cmp(RSA a, RSA b) {
		/* return 0 if a and b are "the same key". Return non-0 otherwise. */

		int result;

		if(!a \|\| !b)
		return -1;

		assert(a->n && a->e && b->n && b->e);

		result = BN_cmp(a->n, b->n);
		if(result)
		return result;
		return BN_cmp(a->e, b->e);
		}

		connection_t *connection_twin_get_by_addr_port(uint32_t addr, uint16_t port) {
		/* Find a connection to the router described by addr and port,
		* or alternately any router which knows its key.
		@@ -99,16 +115,29 @@ connection_t *connection_twin_get_by_addr_port(uint32_t addr, uint16_t port) {
		*/
		int i;
		connection_t *conn;
		routerinfo_t *router;

		/* first check if it's there exactly */
		conn = connection_exact_get_by_addr_port(addr,port);
		if(conn && connection_state_is_open(conn)) {
		log(LOG_DEBUG,"connection_twin_get_by_addr_port(): Found exact match.");
		return conn;
		}

		/* now check if any of the other open connections are a twin for this one */

		/* XXX */
		router = router_get_by_addr_port(addr,port);
		if(!router)
		return NULL;

		for(i=0;i<nfds;i++) {
		conn = connection_array[i];
		assert(conn);
		if(connection_state_is_open(conn) && !pkey_cmp(conn->pkey, router->pkey)) {
		log(LOG_DEBUG,"connection_twin_get_by_addr_port(): Found twin (%s).",conn->address);
		return conn;
		}
		}

		/* guess not */
		return NULL;

src/or/onion.c

+3 −3

Original line number	Diff line number	Diff line
		@@ -131,9 +131,9 @@ unsigned int new_route(double cw, routerinfo_t *rarray, size_t rarray_len, siz

		choice = choice % (rarray_len);
		log(LOG_DEBUG,"new_route() : Chosen router %u.",choice);
		if (choice == oldchoice) /* same router */
		{
		/* try again */
		if (choice == oldchoice \|\|
		(oldchoice < rarray_len && !pkey_cmp(rarray[choice]->pkey, rarray[oldchoice]->pkey))) {
		/* same router, or router twin. try again. */
		i--;
		continue;
		}