commit 83bb9742b541ff53e72c407f45093c137e13a073 Author: Nick Mathewson nickm@torproject.org Date: Tue Sep 27 13:15:36 2011 -0400
Hook up all of the prop176 code; allow v3 negotiations to actually work --- src/or/command.c | 273 ++++++++++++++++++++++++++++++++++++++++++----- src/or/connection_or.c | 242 ++++++++++++++++++++++++++++++------------- src/or/connection_or.h | 12 ++- src/or/or.h | 10 ++ 4 files changed, 435 insertions(+), 102 deletions(-)
diff --git a/src/or/command.c b/src/or/command.c index a32671f..a8e68e1 100644 --- a/src/or/command.c +++ b/src/or/command.c @@ -46,6 +46,15 @@ uint64_t stats_n_versions_cells_processed = 0; /** How many CELL_NETINFO cells have we received, ever? */ uint64_t stats_n_netinfo_cells_processed = 0;
+/** How many CELL_VPADDING cells have we received, ever? */ +uint64_t stats_n_vpadding_cells_processed = 0; +/** How many CELL_CERTS cells have we received, ever? */ +uint64_t stats_n_cert_cells_processed = 0; +/** How many CELL_AUTH_CHALLENGE cells have we received, ever? */ +uint64_t stats_n_auth_challenge_cells_processed = 0; +/** How many CELL_AUTHENTICATE cells have we received, ever? */ +uint64_t stats_n_authenticate_cells_processed = 0; + /* These are the main functions for processing cells */ static void command_process_create_cell(cell_t *cell, or_connection_t *conn); static void command_process_created_cell(cell_t *cell, or_connection_t *conn); @@ -54,6 +63,12 @@ static void command_process_destroy_cell(cell_t *cell, or_connection_t *conn); static void command_process_versions_cell(var_cell_t *cell, or_connection_t *conn); static void command_process_netinfo_cell(cell_t *cell, or_connection_t *conn); +static void command_process_cert_cell(var_cell_t *cell, + or_connection_t *conn); +static void command_process_auth_challenge_cell(var_cell_t *cell, + or_connection_t *conn); +static void command_process_authenticate_cell(var_cell_t *cell, + or_connection_t *conn);
#ifdef KEEP_TIMING_STATS /** This is a wrapper function around the actual function that processes the @@ -93,7 +108,7 @@ command_time_process_cell(cell_t *cell, or_connection_t *conn, int *time, void command_process_cell(cell_t *cell, or_connection_t *conn) { - int handshaking = (conn->_base.state == OR_CONN_STATE_OR_HANDSHAKING_V2); + int handshaking = (conn->_base.state != OR_CONN_STATE_OPEN); #ifdef KEEP_TIMING_STATS /* how many of each cell have we seen so far this second? needs better * name. */ @@ -137,6 +152,10 @@ command_process_cell(cell_t *cell, or_connection_t *conn) if (handshaking && cell->command != CELL_VERSIONS && cell->command != CELL_NETINFO) return; + /* XXXX VERSIONS should be impossible; it's variable-length. */ + + if (conn->_base.state == OR_CONN_STATE_OR_HANDSHAKING_V3) + or_handshake_state_record_cell(conn->handshake_state, cell, 1);
switch (cell->command) { case CELL_PADDING: @@ -206,15 +225,55 @@ command_process_var_cell(var_cell_t *cell, or_connection_t *conn) } #endif
- /* reject all when not handshaking. */ - if (conn->_base.state != OR_CONN_STATE_OR_HANDSHAKING_V2) - return; + switch (conn->_base.state) + { + case OR_CONN_STATE_OR_HANDSHAKING_V2: + if (cell->command != CELL_VERSIONS) + return; + break; + case OR_CONN_STATE_TLS_HANDSHAKING: + /* If we're using bufferevents, it's entirely possible for us to + * notice "hey, data arrived!" before we notice "hey, the handshake + * finished!" And we need to be accepting both at once to handle both + * the v2 and v3 handshakes. */ + + /* fall through */ + case OR_CONN_STATE_TLS_SERVER_RENEGOTIATING: + if (cell->command != CELL_VERSIONS) + return; /*XXXX023 log*/ + break; + case OR_CONN_STATE_OR_HANDSHAKING_V3: + or_handshake_state_record_var_cell(conn->handshake_state, cell, 1); + break; /* Everything is allowed */ + case OR_CONN_STATE_OPEN: + if (conn->link_proto < 3) + return; + default: + /*XXXX023 log */ + return; + }
switch (cell->command) { case CELL_VERSIONS: ++stats_n_versions_cells_processed; PROCESS_CELL(versions, cell, conn); break; + case CELL_VPADDING: + ++stats_n_vpadding_cells_processed; + PROCESS_CELL(versions, cell, conn); + break; + case CELL_CERT: + ++stats_n_cert_cells_processed; + PROCESS_CELL(cert, cell, conn); + break; + case CELL_AUTH_CHALLENGE: + ++stats_n_auth_challenge_cells_processed; + PROCESS_CELL(auth_challenge, cell, conn); + break; + case CELL_AUTHENTICATE: + ++stats_n_authenticate_cells_processed; + PROCESS_CELL(authenticate, cell, conn); + break; default: log_fn(LOG_INFO, LD_PROTOCOL, "Variable-length cell of unknown type (%d) received.", @@ -504,14 +563,40 @@ command_process_versions_cell(var_cell_t *cell, or_connection_t *conn) { int highest_supported_version = 0; const uint8_t *cp, *end; + const int started_here = connection_or_nonopen_was_started_here(conn); if (conn->link_proto != 0 || - conn->_base.state != OR_CONN_STATE_OR_HANDSHAKING_V2 || (conn->handshake_state && conn->handshake_state->received_versions)) { log_fn(LOG_PROTOCOL_WARN, LD_OR, "Received a VERSIONS cell on a connection with its version " "already set to %d; dropping", (int) conn->link_proto); return; } + switch (conn->_base.state) + { + case OR_CONN_STATE_OR_HANDSHAKING_V2: + break; + case OR_CONN_STATE_TLS_HANDSHAKING: + case OR_CONN_STATE_TLS_SERVER_RENEGOTIATING: + if (started_here) { + log_fn(LOG_PROTOCOL_WARN, LD_OR, + "Received a versions cell while TLS-handshaking not in " + "OR_HANDSHAKING_V3 on a connection we originated."); + } + conn->_base.state = OR_CONN_STATE_OR_HANDSHAKING_V3; + if (connection_init_or_handshake_state(conn, started_here) < 0) { + connection_mark_for_close(TO_CONN(conn)); + return; + } + or_handshake_state_record_var_cell(conn->handshake_state, cell, 1); + break; + case OR_CONN_STATE_OR_HANDSHAKING_V3: + break; + default: + log_fn(LOG_PROTOCOL_WARN, LD_OR, + "VERSIONS cell while in unexpected state"); + return; + } + tor_assert(conn->handshake_state); end = cell->payload + cell->payload_len; for (cp = cell->payload; cp+1 < end; ++cp) { @@ -533,19 +618,80 @@ command_process_versions_cell(var_cell_t *cell, or_connection_t *conn) "That's crazily non-compliant. Closing connection."); connection_mark_for_close(TO_CONN(conn)); return; + } else if (highest_supported_version < 3 && + conn->_base.state == OR_CONN_STATE_OR_HANDSHAKING_V3) { + log_fn(LOG_PROTOCOL_WARN, LD_OR, + "Negotiated link protocol 2 or lower after doing a v3 TLS " + "handshake. Closing connection."); + connection_mark_for_close(TO_CONN(conn)); + return; } + conn->link_proto = highest_supported_version; conn->handshake_state->received_versions = 1;
- log_info(LD_OR, "Negotiated version %d with %s:%d; sending NETINFO.", - highest_supported_version, - safe_str_client(conn->_base.address), - conn->_base.port); - tor_assert(conn->link_proto >= 2); + if (conn->link_proto == 2) { + log_info(LD_OR, "Negotiated version %d with %s:%d; sending NETINFO.", + highest_supported_version, + safe_str_client(conn->_base.address), + conn->_base.port);
- if (connection_or_send_netinfo(conn) < 0) { - connection_mark_for_close(TO_CONN(conn)); - return; + if (connection_or_send_netinfo(conn) < 0) { + connection_mark_for_close(TO_CONN(conn)); + return; + } + } else { + const int send_versions = !started_here; + /* If we want to authenticate, send a CERTS cell */ + const int send_certs = !started_here || public_server_mode(get_options()); + /* If we're a relay that got a connection, ask for authentication. */ + const int send_chall = !started_here && public_server_mode(get_options()); + /* If our certs cell will authenticate us, or if we have no intention of + * authenticating, send a netinfo cell right now. */ + const int send_netinfo = + !(started_here && public_server_mode(get_options())); + const int send_any = + send_versions || send_certs || send_chall || send_netinfo; + tor_assert(conn->link_proto >= 3); + + log_info(LD_OR, "Negotiated version %d with %s:%d; %s%s%s%s%s", + highest_supported_version, + safe_str_client(conn->_base.address), + conn->_base.port, + send_any ? "Sending cells:" : "Waiting for CERTS cell", + send_versions ? " VERSIONS" : "", + send_certs ? " CERTS" : "", + send_versions ? " AUTH_CHALLENGE" : "", + send_netinfo ? " NETINFO" : ""); + + if (send_versions) { + if (connection_or_send_versions(conn, 1) < 0) { + log_warn(LD_OR, "Couldn't send versions cell"); + connection_mark_for_close(TO_CONN(conn)); + return; + } + } + if (send_certs) { + if (connection_or_send_cert_cell(conn) < 0) { + log_warn(LD_OR, "Couldn't send cert cell"); + connection_mark_for_close(TO_CONN(conn)); + return; + } + } + if (send_chall) { + if (connection_or_send_auth_challenge_cell(conn) < 0) { + log_warn(LD_OR, "Couldn't send auth_challenge cell"); + connection_mark_for_close(TO_CONN(conn)); + return; + } + } + if (send_netinfo) { + if (connection_or_send_netinfo(conn) < 0) { + log_warn(LD_OR, "Couldn't send netinfo cell"); + connection_mark_for_close(TO_CONN(conn)); + return; + } + } } }
@@ -571,13 +717,26 @@ command_process_netinfo_cell(cell_t *cell, or_connection_t *conn) conn->link_proto == 0 ? "non-versioned" : "a v1"); return; } - if (conn->_base.state != OR_CONN_STATE_OR_HANDSHAKING_V2) { + if (conn->_base.state != OR_CONN_STATE_OR_HANDSHAKING_V2 && + conn->_base.state != OR_CONN_STATE_OR_HANDSHAKING_V3) { log_fn(LOG_PROTOCOL_WARN, LD_OR, "Received a NETINFO cell on non-handshaking connection; dropping."); return; } tor_assert(conn->handshake_state && conn->handshake_state->received_versions); + + if (conn->_base.state == OR_CONN_STATE_OR_HANDSHAKING_V3) { + tor_assert(conn->link_proto >= 3); + if (conn->handshake_state->started_here) { + if (!conn->handshake_state->authenticated) { + log_fn(LOG_PROTOCOL_WARN, LD_OR, "Got a NETINFO cell from server, " + "but no authentication. Closing the connection."); + connection_mark_for_close(TO_CONN(conn)); + } + } + } + /* Decode the cell. */ timestamp = ntohl(get_uint32(cell->payload)); if (labs(now - conn->handshake_state->sent_versions_at) < 180) { @@ -692,8 +851,14 @@ command_process_cert_cell(var_cell_t *cell, or_connection_t *conn)
if (conn->_base.state != OR_CONN_STATE_OR_HANDSHAKING_V3) ERR("We're not doing a v3 handshake!"); + if (conn->link_proto < 3) + ERR("We're not using link protocol >= 3"); if (conn->handshake_state->received_cert_cell) ERR("We already got one"); + if (conn->handshake_state->authenticated) { + /* Should be unreachable, but let's make sure. */ + ERR("We're already authenticated!"); + } if (cell->payload_len < 1) ERR("It had no body"); if (cell->circ_id) @@ -750,7 +915,20 @@ command_process_cert_cell(var_cell_t *cell, or_connection_t *conn) if (! tor_tls_cert_is_valid(id_cert, id_cert, 1)) ERR("The ID certificate was not valid");
- /* XXXX okay, we just got authentication. Do something about that. */ + conn->handshake_state->authenticated = 1; + { + crypto_pk_env_t *identity_rcvd = tor_tls_cert_get_key(id_cert); + const digests_t *id_digests = tor_cert_get_id_digests(id_cert); + memcpy(conn->handshake_state->authenticated_peer_id, + id_digests->d[DIGEST_SHA1], DIGEST_LEN); + connection_or_set_circid_type(conn, identity_rcvd); + crypto_free_pk_env(identity_rcvd); + } + + if (connection_or_client_learned_peer_id(conn, + conn->handshake_state->authenticated_peer_id) < 0) + ERR("Problem setting or checking peer id"); +
conn->handshake_state->id_cert = id_cert; id_cert = NULL; @@ -803,10 +981,14 @@ command_process_auth_challenge_cell(var_cell_t *cell, or_connection_t *conn)
if (conn->_base.state != OR_CONN_STATE_OR_HANDSHAKING_V3) ERR("We're not currently doing a v3 handshake"); + if (conn->link_proto < 3) + ERR("We're not using link protocol >= 3"); if (! conn->handshake_state->started_here) ERR("We didn't originate this connection"); if (conn->handshake_state->received_auth_challenge) ERR("We already received one"); + if (! conn->handshake_state->received_cert_cell) + ERR("We haven't gotten a CERTS cell yet"); if (cell->payload_len < OR_AUTH_CHALLENGE_LEN + 2) ERR("It was too short"); if (cell->circ_id) @@ -829,7 +1011,19 @@ command_process_auth_challenge_cell(var_cell_t *cell, or_connection_t *conn)
conn->handshake_state->received_auth_challenge = 1;
- /* Send back authentication if we want, and if use_type is set */ + if (use_type && public_server_mode(get_options())) { + if (connection_or_send_authenticate_cell(conn, use_type) < 0) { + log_warn(LD_OR, "Couldn't send authenticate cell"); + connection_mark_for_close(TO_CONN(conn)); + return; + } + if (connection_or_send_netinfo(conn) < 0) { + log_warn(LD_OR, "Couldn't send netinfo cell"); + connection_mark_for_close(TO_CONN(conn)); + return; + } + } + #undef ERR }
@@ -842,7 +1036,7 @@ command_process_auth_challenge_cell(var_cell_t *cell, or_connection_t *conn) * the identity of the router on the other side of the connection. */ static void -command_process_authenticate_cell(or_connection_t *conn, var_cell_t *cell) +command_process_authenticate_cell(var_cell_t *cell, or_connection_t *conn) { uint8_t expected[V3_AUTH_FIXED_PART_LEN]; const uint8_t *auth; @@ -859,12 +1053,22 @@ command_process_authenticate_cell(or_connection_t *conn, var_cell_t *cell)
if (conn->_base.state != OR_CONN_STATE_OR_HANDSHAKING_V3) ERR("We're not doing a v3 handshake"); + if (conn->link_proto < 3) + ERR("We're not using link protocol >= 3"); if (! conn->handshake_state->started_here) ERR("We originated this connection"); if (conn->handshake_state->received_authenticate) ERR("We already got one!"); + if (conn->handshake_state->authenticated) { + /* Should be impossible given other checks */ + ERR("The peer is already authenticated"); + } + if (! conn->handshake_state->received_cert_cell) + ERR("We never got a cert cell"); if (conn->handshake_state->auth_cert == NULL) ERR("We never got an authentication certificate"); + if (conn->handshake_state->id_cert == NULL) + ERR("We never got an identity certificate"); if (cell->payload_len < 4) ERR("Cell was way too short");
@@ -915,6 +1119,8 @@ command_process_authenticate_cell(or_connection_t *conn, var_cell_t *cell) tor_free(signed_data); ERR("Not enough data was signed"); } + /* Note that we deliberately allow *more* than DIGEST256_LEN bytes here, + * in case they're later used to hold a SHA3 digest or something. */ if (tor_memneq(signed_data, d, DIGEST256_LEN)) { tor_free(signed_data); ERR("Signature did not match data to be signed."); @@ -922,19 +1128,28 @@ command_process_authenticate_cell(or_connection_t *conn, var_cell_t *cell) tor_free(signed_data); }
- /* XXXX we're authenticated. Now remember the fact, and remember whom we're - authenticated to. */ - + /* Okay, we are authenticated. */ conn->handshake_state->received_authenticate = 1; + conn->handshake_state->authenticated = 1; + { + crypto_pk_env_t *identity_rcvd = + tor_tls_cert_get_key(conn->handshake_state->id_cert); + const digests_t *id_digests = + tor_cert_get_id_digests(conn->handshake_state->id_cert); + + memcpy(conn->handshake_state->authenticated_peer_id, + id_digests->d[DIGEST_SHA1], DIGEST_LEN); + + connection_or_set_circid_type(conn, identity_rcvd); + crypto_free_pk_env(identity_rcvd); + + connection_or_init_conn_from_address(conn, + &conn->_base.addr, + conn->_base.port, + (const char*)conn->handshake_state->authenticated_peer_id, + 0); + } + #undef ERR }
- -void dummy_function(void); -void dummy_function(void) -{ - /* this is only here to avoid 'static function isn't used' warnings */ - command_process_auth_challenge_cell(NULL, NULL); - command_process_cert_cell(NULL, NULL); - command_process_authenticate_cell(NULL, NULL); -} diff --git a/src/or/connection_or.c b/src/or/connection_or.c index 4caa3d3..a391ca7 100644 --- a/src/or/connection_or.c +++ b/src/or/connection_or.c @@ -35,10 +35,8 @@ #endif
static int connection_tls_finish_handshake(or_connection_t *conn); +static int connection_or_launch_v3_or_handshake(or_connection_t *conn); static int connection_or_process_cells_from_inbuf(or_connection_t *conn); -static int connection_or_send_versions(or_connection_t *conn); -static int connection_init_or_handshake_state(or_connection_t *conn, - int started_here); static int connection_or_check_valid_tls_handshake(or_connection_t *conn, int started_here, char *digest_rcvd_out); @@ -388,6 +386,7 @@ connection_or_process_inbuf(or_connection_t *conn) #endif case OR_CONN_STATE_OPEN: case OR_CONN_STATE_OR_HANDSHAKING_V2: + case OR_CONN_STATE_OR_HANDSHAKING_V3: return connection_or_process_cells_from_inbuf(conn); default: return 0; /* don't do anything */ @@ -627,7 +626,7 @@ connection_or_update_token_buckets(smartlist_t *conns, /** If we don't necessarily know the router we're connecting to, but we * have an addr/port/id_digest, then fill in as much as we can. Start * by checking to see if this describes a router we know. */ -static void +void connection_or_init_conn_from_address(or_connection_t *conn, const tor_addr_t *addr, uint16_t port, const char *id_digest, @@ -1180,16 +1179,22 @@ connection_tls_continue_handshake(or_connection_t *conn) if (! tor_tls_used_v1_handshake(conn->tls)) { if (!tor_tls_is_server(conn->tls)) { if (conn->_base.state == OR_CONN_STATE_TLS_HANDSHAKING) { - log_debug(LD_OR, "Done with initial SSL handshake (client-side). " - "Requesting renegotiation."); - conn->_base.state = OR_CONN_STATE_TLS_CLIENT_RENEGOTIATING; - goto again; + if (tor_tls_received_v3_certificate(conn->tls)) { + log_notice(LD_OR, "Client got a v3 cert! Moving on to v3 " + "handshake."); + return connection_or_launch_v3_or_handshake(conn); + } else { + log_debug(LD_OR, "Done with initial SSL handshake (client-side). " + "Requesting renegotiation."); + conn->_base.state = OR_CONN_STATE_TLS_CLIENT_RENEGOTIATING; + goto again; + } } // log_notice(LD_OR,"Done. state was %d.", conn->_base.state); } else { - /* improved handshake, but not a client. */ + /* v2/v3 handshake, but not a client. */ log_debug(LD_OR, "Done with initial SSL handshake (server-side). " - "Expecting renegotiation."); + "Expecting renegotiation or VERSIONS cell"); tor_tls_set_renegotiate_callback(conn->tls, connection_or_tls_renegotiated_cb, conn); @@ -1234,17 +1239,24 @@ connection_or_handle_event_cb(struct bufferevent *bufev, short event, if (! tor_tls_used_v1_handshake(conn->tls)) { if (!tor_tls_is_server(conn->tls)) { if (conn->_base.state == OR_CONN_STATE_TLS_HANDSHAKING) { - conn->_base.state = OR_CONN_STATE_TLS_CLIENT_RENEGOTIATING; - tor_tls_unblock_renegotiation(conn->tls); - if (bufferevent_ssl_renegotiate(conn->_base.bufev)<0) { - log_warn(LD_OR, "Start_renegotiating went badly."); - connection_mark_for_close(TO_CONN(conn)); + if (tor_tls_received_v3_certificate(conn->tls)) { + log_notice(LD_OR, "Client got a v3 cert!"); + if (connection_or_launch_v3_or_handshake(conn) < 0) + connection_mark_for_close(TO_CONN(conn)); + return; + } else { + conn->_base.state = OR_CONN_STATE_TLS_CLIENT_RENEGOTIATING; + tor_tls_unblock_renegotiation(conn->tls); + if (bufferevent_ssl_renegotiate(conn->_base.bufev)<0) { + log_warn(LD_OR, "Start_renegotiating went badly."); + connection_mark_for_close(TO_CONN(conn)); + } + tor_tls_unblock_renegotiation(conn->tls); + return; /* ???? */ } - tor_tls_unblock_renegotiation(conn->tls); - return; /* ???? */ } } else if (tor_tls_get_num_server_handshakes(conn->tls) == 1) { - /* improved handshake, as a server. Only got one handshake, so + /* v2 or v3 handshake, as a server. Only got one handshake, so * wait for the next one. */ tor_tls_set_renegotiate_callback(conn->tls, connection_or_tls_renegotiated_cb, @@ -1256,7 +1268,7 @@ connection_or_handle_event_cb(struct bufferevent *bufev, short event, const int handshakes = tor_tls_get_num_server_handshakes(conn->tls); tor_assert(handshakes >= 2); if (handshakes == 2) { - /* improved handshake, as a server. Two handshakes happened already, + /* v2 handshake, as a server. Two handshakes happened already, * so we treat renegotiation as done. */ connection_or_tls_renegotiated_cb(conn->tls, conn); @@ -1300,6 +1312,29 @@ connection_or_nonopen_was_started_here(or_connection_t *conn) return !tor_tls_is_server(conn->tls); }
+/** Set the circid_type field of <b>conn</b> (which determines which part of + * the circuit ID space we're willing to use) based on comparing our ID to + * <b>identity_rcvd</b> */ +void +connection_or_set_circid_type(or_connection_t *conn, + crypto_pk_env_t *identity_rcvd) +{ + const int started_here = connection_or_nonopen_was_started_here(conn); + crypto_pk_env_t *our_identity = + started_here ? get_tlsclient_identity_key() : + get_server_identity_key(); + + if (identity_rcvd) { + if (crypto_pk_cmp_keys(our_identity, identity_rcvd)<0) { + conn->circ_id_type = CIRC_ID_TYPE_LOWER; + } else { + conn->circ_id_type = CIRC_ID_TYPE_HIGHER; + } + } else { + conn->circ_id_type = CIRC_ID_TYPE_NEITHER; + } +} + /** <b>Conn</b> just completed its handshake. Return 0 if all is well, and * return -1 if he is lying, broken, or otherwise something is wrong. * @@ -1337,10 +1372,7 @@ connection_or_check_valid_tls_handshake(or_connection_t *conn, started_here ? conn->_base.address : safe_str_client(conn->_base.address); const char *conn_type = started_here ? "outgoing" : "incoming"; - crypto_pk_env_t *our_identity = - started_here ? get_tlsclient_identity_key() : - get_server_identity_key(); - int has_cert = 0, has_identity=0; + int has_cert = 0;
check_no_tls_errors(); has_cert = tor_tls_peer_has_cert(conn->tls); @@ -1375,21 +1407,46 @@ connection_or_check_valid_tls_handshake(or_connection_t *conn, }
if (identity_rcvd) { - has_identity = 1; crypto_pk_get_digest(identity_rcvd, digest_rcvd_out); - if (crypto_pk_cmp_keys(our_identity, identity_rcvd)<0) { - conn->circ_id_type = CIRC_ID_TYPE_LOWER; - } else { - conn->circ_id_type = CIRC_ID_TYPE_HIGHER; - } - crypto_free_pk_env(identity_rcvd); } else { memset(digest_rcvd_out, 0, DIGEST_LEN); - conn->circ_id_type = CIRC_ID_TYPE_NEITHER; }
- if (started_here && tor_digest_is_zero(conn->identity_digest)) { - connection_or_set_identity_digest(conn, digest_rcvd_out); + connection_or_set_circid_type(conn, identity_rcvd); + crypto_free_pk_env(identity_rcvd); + + if (started_here) + return connection_or_client_learned_peer_id(conn, + (const uint8_t*)digest_rcvd_out); + + return 0; +} + +/** Called when we (as a connection initiator) have definitively, + * authenticatedly, learned that ID of the Tor instance on the other + * side of <b>conn</b> is <b>peer_id</b>. For v1 and v2 handshakes, + * this is right after we get a certificate chain in a TLS handshake + * or renegotiation. For v3 handshakes, this is right after we get a + * certificate chain in a CERT cell. + * + * If we want any particular ID before, record the one we got. + * + * If we wanted an ID, but we didn't get it, log a warning and return -1. + * + * If we're testing reachability, remember what we learned. + * + * Return 0 on success, -1 on failure. + */ +int +connection_or_client_learned_peer_id(or_connection_t *conn, + const uint8_t *peer_id) +{ + int as_expected = 1; + const or_options_t *options = get_options(); + int severity = server_mode(options) ? LOG_PROTOCOL_WARN : LOG_WARN; + + if (tor_digest_is_zero(conn->identity_digest)) { + connection_or_set_identity_digest(conn, (const char*)peer_id); tor_free(conn->nickname); conn->nickname = tor_malloc(HEX_DIGEST_LEN+2); conn->nickname[0] = '$'; @@ -1401,43 +1458,39 @@ connection_or_check_valid_tls_handshake(or_connection_t *conn, /* if it's a bridge and we didn't know its identity fingerprint, now * we do -- remember it for future attempts. */ learned_router_identity(&conn->_base.addr, conn->_base.port, - digest_rcvd_out); + (const char*)peer_id); }
- if (started_here) { - int as_advertised = 1; - tor_assert(has_cert); - tor_assert(has_identity); - if (tor_memneq(digest_rcvd_out, conn->identity_digest, DIGEST_LEN)) { - /* I was aiming for a particular digest. I didn't get it! */ - char seen[HEX_DIGEST_LEN+1]; - char expected[HEX_DIGEST_LEN+1]; - base16_encode(seen, sizeof(seen), digest_rcvd_out, DIGEST_LEN); - base16_encode(expected, sizeof(expected), conn->identity_digest, - DIGEST_LEN); - log_fn(severity, LD_HANDSHAKE, - "Tried connecting to router at %s:%d, but identity key was not " - "as expected: wanted %s but got %s.", - conn->_base.address, conn->_base.port, expected, seen); - entry_guard_register_connect_status(conn->identity_digest, 0, 1, - time(NULL)); - control_event_or_conn_status(conn, OR_CONN_EVENT_FAILED, - END_OR_CONN_REASON_OR_IDENTITY); - if (!authdir_mode_tests_reachability(options)) - control_event_bootstrap_problem("foo", END_OR_CONN_REASON_OR_IDENTITY); - as_advertised = 0; - } - if (authdir_mode_tests_reachability(options)) { - dirserv_orconn_tls_done(conn->_base.address, conn->_base.port, - digest_rcvd_out, as_advertised); - } - if (!as_advertised) - return -1; + if (tor_memneq(peer_id, conn->identity_digest, DIGEST_LEN)) { + /* I was aiming for a particular digest. I didn't get it! */ + char seen[HEX_DIGEST_LEN+1]; + char expected[HEX_DIGEST_LEN+1]; + base16_encode(seen, sizeof(seen), (const char*)peer_id, DIGEST_LEN); + base16_encode(expected, sizeof(expected), conn->identity_digest, + DIGEST_LEN); + log_fn(severity, LD_HANDSHAKE, + "Tried connecting to router at %s:%d, but identity key was not " + "as expected: wanted %s but got %s.", + conn->_base.address, conn->_base.port, expected, seen); + entry_guard_register_connect_status(conn->identity_digest, 0, 1, + time(NULL)); + control_event_or_conn_status(conn, OR_CONN_EVENT_FAILED, + END_OR_CONN_REASON_OR_IDENTITY); + if (!authdir_mode_tests_reachability(options)) + control_event_bootstrap_problem("foo", END_OR_CONN_REASON_OR_IDENTITY); + as_expected = 0; + } + if (authdir_mode_tests_reachability(options)) { + dirserv_orconn_tls_done(conn->_base.address, conn->_base.port, + (const char*)peer_id, as_expected); } + if (!as_expected) + return -1; + return 0; }
-/** The tls handshake is finished. +/** The v1/v2 TLS handshake is finished. * * Make sure we are happy with the person we just handshaked with. * @@ -1447,6 +1500,8 @@ connection_or_check_valid_tls_handshake(or_connection_t *conn, * If all is successful, call circuit_n_conn_done() to handle events * that have been pending on the <tls handshake completion. Also set the * directory to be dirty (only matters if I'm an authdirserver). + * + * If this is a v2 TLS handshake, send a versions cell. */ static int connection_tls_finish_handshake(or_connection_t *conn) @@ -1483,13 +1538,35 @@ connection_tls_finish_handshake(or_connection_t *conn) connection_or_init_conn_from_address(conn, &conn->_base.addr, conn->_base.port, digest_rcvd, 0); } - return connection_or_send_versions(conn); + return connection_or_send_versions(conn, 0); } }
+/** + * Called as client when initial TLS handshake is done, and we notice + * that we got a v3-handshake signalling certificate from the server. + * Set up structures, do bookkeeping, and send the versions cell. + * Return 0 on success and -1 on failure. + */ +static int +connection_or_launch_v3_or_handshake(or_connection_t *conn) +{ + tor_assert(connection_or_nonopen_was_started_here(conn)); + tor_assert(tor_tls_received_v3_certificate(conn->tls)); + + circuit_build_times_network_is_live(&circ_times); + + conn->_base.state = OR_CONN_STATE_OR_HANDSHAKING_V3; + if (connection_init_or_handshake_state(conn, 1) < 0) + return -1; + + return connection_or_send_versions(conn, 1); +} + + /** Allocate a new connection handshake state for the connection * <b>conn</b>. Return 0 on success, -1 on failure. */ -static int +int connection_init_or_handshake_state(or_connection_t *conn, int started_here) { or_handshake_state_t *s; @@ -1639,6 +1716,9 @@ connection_or_write_cell_to_buf(const cell_t *cell, or_connection_t *conn)
connection_write_to_buf(networkcell.body, CELL_NETWORK_SIZE, TO_CONN(conn));
+ if (conn->_base.state == OR_CONN_STATE_OR_HANDSHAKING_V3) + or_handshake_state_record_cell(conn->handshake_state, cell, 0); + if (cell->command != CELL_PADDING) conn->timestamp_last_added_nonpadding = approx_time(); } @@ -1658,6 +1738,8 @@ connection_or_write_var_cell_to_buf(const var_cell_t *cell, connection_write_to_buf(hdr, sizeof(hdr), TO_CONN(conn)); connection_write_to_buf((char*)cell->payload, cell->payload_len, TO_CONN(conn)); + if (conn->_base.state == OR_CONN_STATE_OR_HANDSHAKING_V3) + or_handshake_state_record_var_cell(conn->handshake_state, cell, 0); if (cell->command != CELL_PADDING) conn->timestamp_last_added_nonpadding = approx_time(); } @@ -1742,7 +1824,7 @@ connection_or_send_destroy(circid_t circ_id, or_connection_t *conn, int reason) }
/** Array of recognized link protocol versions. */ -static const uint16_t or_protocol_versions[] = { 1, 2 }; +static const uint16_t or_protocol_versions[] = { 1, 2, 3 }; /** Number of versions in <b>or_protocol_versions</b>. */ static const int n_or_protocol_versions = (int)( sizeof(or_protocol_versions)/sizeof(uint16_t) ); @@ -1761,20 +1843,33 @@ is_or_protocol_version_known(uint16_t v) }
/** Send a VERSIONS cell on <b>conn</b>, telling the other host about the - * link protocol versions that this Tor can support. */ -static int -connection_or_send_versions(or_connection_t *conn) + * link protocol versions that this Tor can support. + * + * If <b>v3_plus</b>, this is part of a V3 protocol handshake, so only + * allow protocol version v3 or later. If not <b>v3_plus</b>, this is + * not part of a v3 protocol handshake, so don't allow protocol v3 or + * later. + **/ +int +connection_or_send_versions(or_connection_t *conn, int v3_plus) { var_cell_t *cell; int i; + int n_versions = 0; + const int min_version = v3_plus ? 3 : 0; + const int max_version = v3_plus ? UINT16_MAX : 2; tor_assert(conn->handshake_state && !conn->handshake_state->sent_versions_at); cell = var_cell_new(n_or_protocol_versions * 2); cell->command = CELL_VERSIONS; for (i = 0; i < n_or_protocol_versions; ++i) { uint16_t v = or_protocol_versions[i]; - set_uint16(cell->payload+(2*i), htons(v)); + if (v < min_version || v > max_version) + continue; + set_uint16(cell->payload+(2*n_versions), htons(v)); + ++n_versions; } + cell->payload_len = n_versions * 2;
connection_or_write_var_cell_to_buf(cell, conn); conn->handshake_state->sent_versions_at = time(NULL); @@ -2047,7 +2142,7 @@ connection_or_compute_authenticate_cell_body(or_connection_t *conn, /** Send an AUTHENTICATE cell on the connection <b>conn</b>. Return 0 on * success, -1 on failure */ int -connection_or_send_authenticate_cell(or_connection_t *conn) +connection_or_send_authenticate_cell(or_connection_t *conn, int authtype) { var_cell_t *cell; crypto_pk_env_t *pk = tor_tls_get_my_client_auth_key(); @@ -2057,6 +2152,9 @@ connection_or_send_authenticate_cell(or_connection_t *conn)
if (!pk) return -1;/*XXXX log*/ + if (authtype != AUTHTYPE_RSA_SHA256_TLSSECRET) + return -1;/*XXXX log*/ + cell_maxlen = 4 + /* overhead */ V3_AUTH_BODY_LEN + /* Authentication body */ crypto_pk_keysize(pk) + /* Max signature length */ diff --git a/src/or/connection_or.h b/src/or/connection_or.h index a4d3be0..de3a989 100644 --- a/src/or/connection_or.h +++ b/src/or/connection_or.h @@ -41,6 +41,15 @@ void connection_or_report_broken_states(int severity, int domain); int connection_tls_start_handshake(or_connection_t *conn, int receiving); int connection_tls_continue_handshake(or_connection_t *conn);
+int connection_init_or_handshake_state(or_connection_t *conn, int started_here); +void connection_or_init_conn_from_address(or_connection_t *conn, + const tor_addr_t *addr, uint16_t port, + const char *id_digest, + int started_here); +int connection_or_client_learned_peer_id(or_connection_t *conn, + const uint8_t *peer_id); +void connection_or_set_circid_type(or_connection_t *conn, + crypto_pk_env_t *identity_rcvd); void or_handshake_state_free(or_handshake_state_t *state); void or_handshake_state_record_cell(or_handshake_state_t *state, const cell_t *cell, @@ -56,6 +65,7 @@ void connection_or_write_var_cell_to_buf(const var_cell_t *cell, or_connection_t *conn); int connection_or_send_destroy(circid_t circ_id, or_connection_t *conn, int reason); +int connection_or_send_versions(or_connection_t *conn, int v3_plus); int connection_or_send_netinfo(or_connection_t *conn); int connection_or_send_cert_cell(or_connection_t *conn); int connection_or_send_auth_challenge_cell(or_connection_t *conn); @@ -63,7 +73,7 @@ int connection_or_compute_authenticate_cell_body(or_connection_t *conn, uint8_t *out, size_t outlen, crypto_pk_env_t *signing_key, int server); -int connection_or_send_authenticate_cell(or_connection_t *conn); +int connection_or_send_authenticate_cell(or_connection_t *conn, int type);
int is_or_protocol_version_known(uint16_t version);
diff --git a/src/or/or.h b/src/or/or.h index a40598f..887dcb6 100644 --- a/src/or/or.h +++ b/src/or/or.h @@ -1142,6 +1142,16 @@ typedef struct or_handshake_state_t { /** True iff we have received and processed an AUTHENTICATE cell */ unsigned int received_authenticate : 1;
+ /* True iff we've received valid authentication to some identity. */ + unsigned int authenticated : 1; + + /** Identity digest that we have received and authenticated for our peer + * on this connection. */ + uint8_t authenticated_peer_id[DIGEST_LEN]; + + /** DOCDOC */ + uint8_t auth_challenge[OR_AUTH_CHALLENGE_LEN]; + /** Digests of the cells that we have sent or received as part of a V3 * handshake. Used for making and checking AUTHENTICATE cells. *