/* Copyright (c) 2001 Matej Pfajfar. * Copyright (c) 2001-2004, Roger Dingledine. * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. * Copyright (c) 2007-2018, The Tor Project, Inc. */ /* See LICENSE for licensing information */ /** * \file connection_edge.c * \brief Handle edge streams. * * An edge_connection_t is a subtype of a connection_t, and represents two * critical concepts in Tor: a stream, and an edge connection. From the Tor * protocol's point of view, a stream is a bi-directional channel that is * multiplexed on a single circuit. Each stream on a circuit is identified * with a separate 16-bit stream ID, local to the (circuit,exit) pair. * Streams are created in response to client requests. * * An edge connection is one thing that can implement a stream: it is either a * TCP application socket that has arrived via (e.g.) a SOCKS request, or an * exit connection. * * Not every instance of edge_connection_t truly represents an edge connction, * however. (Sorry!) We also create edge_connection_t objects for streams that * we will not be handling with TCP. The types of these streams are: * * * This module handles general-purpose functionality having to do with * edge_connection_t. On the client side, it accepts various types of * application requests on SocksPorts, TransPorts, and NATDPorts, and * creates streams appropriately. * * This module is also responsible for implementing stream isolation: * ensuring that streams that should not be linkable to one another are * kept to different circuits. * * On the exit side, this module handles the various stream-creating * type of RELAY cells by launching appropriate outgoing connections, * DNS requests, or directory connection objects. * * And for all edge connections, this module is responsible for handling * incoming and outdoing data as it arrives or leaves in the relay.c * module. (Outgoing data will be packaged in * connection_edge_process_inbuf() as it calls * connection_edge_package_raw_inbuf(); incoming data from RELAY_DATA * cells is applied in connection_edge_process_relay_cell().) **/ #define CONNECTION_EDGE_PRIVATE #include "or/or.h" #include "common/backtrace.h" #include "or/addressmap.h" #include "common/buffers.h" #include "or/channel.h" #include "or/circpathbias.h" #include "or/circuitlist.h" #include "or/circuituse.h" #include "or/config.h" #include "or/connection.h" #include "or/connection_edge.h" #include "or/connection_or.h" #include "or/control.h" #include "common/crypto_util.h" #include "or/dns.h" #include "or/dnsserv.h" #include "or/directory.h" #include "or/dirserv.h" #include "or/hibernate.h" #include "or/hs_common.h" #include "or/hs_cache.h" #include "or/hs_client.h" #include "or/hs_circuit.h" #include "or/main.h" #include "or/networkstatus.h" #include "or/nodelist.h" #include "or/policies.h" #include "or/proto_http.h" #include "or/proto_socks.h" #include "or/reasons.h" #include "or/relay.h" #include "or/rendclient.h" #include "or/rendcommon.h" #include "or/rendservice.h" #include "or/rephist.h" #include "or/router.h" #include "or/routerlist.h" #include "or/routerset.h" #include "or/circuitbuild.h" #include "or/cell_st.h" #include "or/cpath_build_state_st.h" #include "or/dir_connection_st.h" #include "or/entry_connection_st.h" #include "or/extend_info_st.h" #include "or/node_st.h" #include "or/or_circuit_st.h" #include "or/origin_circuit_st.h" #include "or/socks_request_st.h" #ifdef HAVE_LINUX_TYPES_H #include #endif #ifdef HAVE_LINUX_NETFILTER_IPV4_H #include #define TRANS_NETFILTER #define TRANS_NETFILTER_IPV4 #endif #ifdef HAVE_LINUX_IF_H #include #endif #ifdef HAVE_LINUX_NETFILTER_IPV6_IP6_TABLES_H #include #if defined(IP6T_SO_ORIGINAL_DST) #define TRANS_NETFILTER #define TRANS_NETFILTER_IPV6 #endif #endif /* defined(HAVE_LINUX_NETFILTER_IPV6_IP6_TABLES_H) */ #if defined(HAVE_NET_IF_H) && defined(HAVE_NET_PFVAR_H) #include #include #define TRANS_PF #endif #ifdef IP_TRANSPARENT #define TRANS_TPROXY #endif #define SOCKS4_GRANTED 90 #define SOCKS4_REJECT 91 static int connection_ap_handshake_process_socks(entry_connection_t *conn); static int connection_ap_process_natd(entry_connection_t *conn); static int connection_exit_connect_dir(edge_connection_t *exitconn); static int consider_plaintext_ports(entry_connection_t *conn, uint16_t port); static int connection_ap_supports_optimistic_data(const entry_connection_t *); /** Convert a connection_t* to an edge_connection_t*; assert if the cast is * invalid. */ edge_connection_t * TO_EDGE_CONN(connection_t *c) { tor_assert(c->magic == EDGE_CONNECTION_MAGIC || c->magic == ENTRY_CONNECTION_MAGIC); return DOWNCAST(edge_connection_t, c); } entry_connection_t * TO_ENTRY_CONN(connection_t *c) { tor_assert(c->magic == ENTRY_CONNECTION_MAGIC); return (entry_connection_t*) SUBTYPE_P(c, entry_connection_t, edge_.base_); } entry_connection_t * EDGE_TO_ENTRY_CONN(edge_connection_t *c) { tor_assert(c->base_.magic == ENTRY_CONNECTION_MAGIC); return (entry_connection_t*) SUBTYPE_P(c, entry_connection_t, edge_); } /** An AP stream has failed/finished. If it hasn't already sent back * a socks reply, send one now (based on endreason). Also set * has_sent_end to 1, and mark the conn. */ MOCK_IMPL(void, connection_mark_unattached_ap_,(entry_connection_t *conn, int endreason, int line, const char *file)) { connection_t *base_conn = ENTRY_TO_CONN(conn); edge_connection_t *edge_conn = ENTRY_TO_EDGE_CONN(conn); tor_assert(base_conn->type == CONN_TYPE_AP); ENTRY_TO_EDGE_CONN(conn)->edge_has_sent_end = 1; /* no circ yet */ /* If this is a rendezvous stream and it is failing without ever * being attached to a circuit, assume that an attempt to connect to * the destination hidden service has just ended. * * XXXX This condition doesn't limit to only streams failing * without ever being attached. That sloppiness should be harmless, * but we should fix it someday anyway. */ if ((edge_conn->on_circuit != NULL || edge_conn->edge_has_sent_end) && connection_edge_is_rendezvous_stream(edge_conn)) { if (edge_conn->rend_data) { rend_client_note_connection_attempt_ended(edge_conn->rend_data); } } if (base_conn->marked_for_close) { /* This call will warn as appropriate. */ connection_mark_for_close_(base_conn, line, file); return; } if (!conn->socks_request->has_finished) { if (endreason & END_STREAM_REASON_FLAG_ALREADY_SOCKS_REPLIED) log_warn(LD_BUG, "stream (marked at %s:%d) sending two socks replies?", file, line); if (SOCKS_COMMAND_IS_CONNECT(conn->socks_request->command)) connection_ap_handshake_socks_reply(conn, NULL, 0, endreason); else if (SOCKS_COMMAND_IS_RESOLVE(conn->socks_request->command)) connection_ap_handshake_socks_resolved(conn, RESOLVED_TYPE_ERROR_TRANSIENT, 0, NULL, -1, -1); else /* unknown or no handshake at all. send no response. */ conn->socks_request->has_finished = 1; } connection_mark_and_flush_(base_conn, line, file); ENTRY_TO_EDGE_CONN(conn)->end_reason = endreason; } /** There was an EOF. Send an end and mark the connection for close. */ int connection_edge_reached_eof(edge_connection_t *conn) { if (connection_get_inbuf_len(TO_CONN(conn)) && connection_state_is_open(TO_CONN(conn))) { /* it still has stuff to process. don't let it die yet. */ return 0; } log_info(LD_EDGE,"conn (fd "TOR_SOCKET_T_FORMAT") reached eof. Closing.", conn->base_.s); if (!conn->base_.marked_for_close) { /* only mark it if not already marked. it's possible to * get the 'end' right around when the client hangs up on us. */ connection_edge_end(conn, END_STREAM_REASON_DONE); if (conn->base_.type == CONN_TYPE_AP) { /* eof, so don't send a socks reply back */ if (EDGE_TO_ENTRY_CONN(conn)->socks_request) EDGE_TO_ENTRY_CONN(conn)->socks_request->has_finished = 1; } connection_mark_for_close(TO_CONN(conn)); } return 0; } /** Handle new bytes on conn->inbuf based on state: * - If it's waiting for socks info, try to read another step of the * socks handshake out of conn->inbuf. * - If it's waiting for the original destination, fetch it. * - If it's open, then package more relay cells from the stream. * - Else, leave the bytes on inbuf alone for now. * * Mark and return -1 if there was an unexpected error with the conn, * else return 0. */ int connection_edge_process_inbuf(edge_connection_t *conn, int package_partial) { tor_assert(conn); switch (conn->base_.state) { case AP_CONN_STATE_SOCKS_WAIT: if (connection_ap_handshake_process_socks(EDGE_TO_ENTRY_CONN(conn)) <0) { /* already marked */ return -1; } return 0; case AP_CONN_STATE_NATD_WAIT: if (connection_ap_process_natd(EDGE_TO_ENTRY_CONN(conn)) < 0) { /* already marked */ return -1; } return 0; case AP_CONN_STATE_HTTP_CONNECT_WAIT: if (connection_ap_process_http_connect(EDGE_TO_ENTRY_CONN(conn)) < 0) { return -1; } return 0; case AP_CONN_STATE_OPEN: case EXIT_CONN_STATE_OPEN: if (connection_edge_package_raw_inbuf(conn, package_partial, NULL) < 0) { /* (We already sent an end cell if possible) */ connection_mark_for_close(TO_CONN(conn)); return -1; } return 0; case AP_CONN_STATE_CONNECT_WAIT: if (connection_ap_supports_optimistic_data(EDGE_TO_ENTRY_CONN(conn))) { log_info(LD_EDGE, "data from edge while in '%s' state. Sending it anyway. " "package_partial=%d, buflen=%ld", conn_state_to_string(conn->base_.type, conn->base_.state), package_partial, (long)connection_get_inbuf_len(TO_CONN(conn))); if (connection_edge_package_raw_inbuf(conn, package_partial, NULL)<0) { /* (We already sent an end cell if possible) */ connection_mark_for_close(TO_CONN(conn)); return -1; } return 0; } /* Fall through if the connection is on a circuit without optimistic * data support. */ /* Falls through. */ case EXIT_CONN_STATE_CONNECTING: case AP_CONN_STATE_RENDDESC_WAIT: case AP_CONN_STATE_CIRCUIT_WAIT: case AP_CONN_STATE_RESOLVE_WAIT: case AP_CONN_STATE_CONTROLLER_WAIT: log_info(LD_EDGE, "data from edge while in '%s' state. Leaving it on buffer.", conn_state_to_string(conn->base_.type, conn->base_.state)); return 0; } log_warn(LD_BUG,"Got unexpected state %d. Closing.",conn->base_.state); tor_fragile_assert(); connection_edge_end(conn, END_STREAM_REASON_INTERNAL); connection_mark_for_close(TO_CONN(conn)); return -1; } /** This edge needs to be closed, because its circuit has closed. * Mark it for close and return 0. */ int connection_edge_destroy(circid_t circ_id, edge_connection_t *conn) { if (!conn->base_.marked_for_close) { log_info(LD_EDGE, "CircID %u: At an edge. Marking connection for close.", (unsigned) circ_id); if (conn->base_.type == CONN_TYPE_AP) { entry_connection_t *entry_conn = EDGE_TO_ENTRY_CONN(conn); connection_mark_unattached_ap(entry_conn, END_STREAM_REASON_DESTROY); control_event_stream_bandwidth(conn); control_event_stream_status(entry_conn, STREAM_EVENT_CLOSED, END_STREAM_REASON_DESTROY); conn->end_reason |= END_STREAM_REASON_FLAG_ALREADY_SENT_CLOSED; } else { /* closing the circuit, nothing to send an END to */ conn->edge_has_sent_end = 1; conn->end_reason = END_STREAM_REASON_DESTROY; conn->end_reason |= END_STREAM_REASON_FLAG_ALREADY_SENT_CLOSED; connection_mark_and_flush(TO_CONN(conn)); } } conn->cpath_layer = NULL; conn->on_circuit = NULL; return 0; } /** Send a raw end cell to the stream with ID stream_id out over the * circ towards the hop identified with cpath_layer. If this * is not a client connection, set the relay end cell's reason for closing * as reason */ static int relay_send_end_cell_from_edge(streamid_t stream_id, circuit_t *circ, uint8_t reason, crypt_path_t *cpath_layer) { char payload[1]; if (CIRCUIT_PURPOSE_IS_CLIENT(circ->purpose)) { /* Never send the server an informative reason code; it doesn't need to * know why the client stream is failing. */ reason = END_STREAM_REASON_MISC; } payload[0] = (char) reason; /* Note: we have to use relay_send_command_from_edge here, not * connection_edge_end or connection_edge_send_command, since those require * that we have a stream connected to a circuit, and we don't connect to a * circuit until we have a pending/successful resolve. */ return relay_send_command_from_edge(stream_id, circ, RELAY_COMMAND_END, payload, 1, cpath_layer); } /* If the connection conn is attempting to connect to an external * destination that is an hidden service and the reason is a connection * refused or timeout, log it so the operator can take appropriate actions. * The log statement is a rate limited warning. */ static void warn_if_hs_unreachable(const edge_connection_t *conn, uint8_t reason) { tor_assert(conn); if (conn->base_.type == CONN_TYPE_EXIT && connection_edge_is_rendezvous_stream(conn) && (reason == END_STREAM_REASON_CONNECTREFUSED || reason == END_STREAM_REASON_TIMEOUT)) { #define WARN_FAILED_HS_CONNECTION 300 static ratelim_t warn_limit = RATELIM_INIT(WARN_FAILED_HS_CONNECTION); char *m; if ((m = rate_limit_log(&warn_limit, approx_time()))) { log_warn(LD_EDGE, "Onion service connection to %s failed (%s)", (conn->base_.socket_family == AF_UNIX) ? safe_str(conn->base_.address) : safe_str(fmt_addrport(&conn->base_.addr, conn->base_.port)), stream_end_reason_to_string(reason)); tor_free(m); } } } /** Send a relay end cell from stream conn down conn's circuit, and * remember that we've done so. If this is not a client connection, set the * relay end cell's reason for closing as reason. * * Return -1 if this function has already been called on this conn, * else return 0. */ int connection_edge_end(edge_connection_t *conn, uint8_t reason) { char payload[RELAY_PAYLOAD_SIZE]; size_t payload_len=1; circuit_t *circ; uint8_t control_reason = reason; if (conn->edge_has_sent_end) { log_warn(LD_BUG,"(Harmless.) Calling connection_edge_end (reason %d) " "on an already ended stream?", reason); tor_fragile_assert(); return -1; } if (conn->base_.marked_for_close) { log_warn(LD_BUG, "called on conn that's already marked for close at %s:%d.", conn->base_.marked_for_close_file, conn->base_.marked_for_close); return 0; } circ = circuit_get_by_edge_conn(conn); if (circ && CIRCUIT_PURPOSE_IS_CLIENT(circ->purpose)) { /* If this is a client circuit, don't send the server an informative * reason code; it doesn't need to know why the client stream is * failing. */ reason = END_STREAM_REASON_MISC; } payload[0] = (char)reason; if (reason == END_STREAM_REASON_EXITPOLICY && !connection_edge_is_rendezvous_stream(conn)) { int addrlen; if (tor_addr_family(&conn->base_.addr) == AF_INET) { set_uint32(payload+1, tor_addr_to_ipv4n(&conn->base_.addr)); addrlen = 4; } else { memcpy(payload+1, tor_addr_to_in6_addr8(&conn->base_.addr), 16); addrlen = 16; } set_uint32(payload+1+addrlen, htonl(dns_clip_ttl(conn->address_ttl))); payload_len += 4+addrlen; } if (circ && !circ->marked_for_close) { log_debug(LD_EDGE,"Sending end on conn (fd "TOR_SOCKET_T_FORMAT").", conn->base_.s); connection_edge_send_command(conn, RELAY_COMMAND_END, payload, payload_len); /* We'll log warn if the connection was an hidden service and couldn't be * made because the service wasn't available. */ warn_if_hs_unreachable(conn, control_reason); } else { log_debug(LD_EDGE,"No circ to send end on conn " "(fd "TOR_SOCKET_T_FORMAT").", conn->base_.s); } conn->edge_has_sent_end = 1; conn->end_reason = control_reason; return 0; } /** An error has just occurred on an operation on an edge connection * conn. Extract the errno; convert it to an end reason, and send an * appropriate relay end cell to the other end of the connection's circuit. **/ int connection_edge_end_errno(edge_connection_t *conn) { uint8_t reason; tor_assert(conn); reason = errno_to_stream_end_reason(tor_socket_errno(conn->base_.s)); return connection_edge_end(conn, reason); } /** We just wrote some data to conn; act appropriately. * * (That is, if it's open, consider sending a stream-level sendme cell if we * have just flushed enough.) */ int connection_edge_flushed_some(edge_connection_t *conn) { switch (conn->base_.state) { case AP_CONN_STATE_OPEN: case EXIT_CONN_STATE_OPEN: connection_edge_consider_sending_sendme(conn); break; } return 0; } /** Connection conn has finished writing and has no bytes left on * its outbuf. * * If it's in state 'open', stop writing, consider responding with a * sendme, and return. * Otherwise, stop writing and return. * * If conn is broken, mark it for close and return -1, else * return 0. */ int connection_edge_finished_flushing(edge_connection_t *conn) { tor_assert(conn); switch (conn->base_.state) { case AP_CONN_STATE_OPEN: case EXIT_CONN_STATE_OPEN: connection_edge_consider_sending_sendme(conn); return 0; case AP_CONN_STATE_SOCKS_WAIT: case AP_CONN_STATE_NATD_WAIT: case AP_CONN_STATE_RENDDESC_WAIT: case AP_CONN_STATE_CIRCUIT_WAIT: case AP_CONN_STATE_CONNECT_WAIT: case AP_CONN_STATE_CONTROLLER_WAIT: case AP_CONN_STATE_RESOLVE_WAIT: case AP_CONN_STATE_HTTP_CONNECT_WAIT: return 0; default: log_warn(LD_BUG, "Called in unexpected state %d.",conn->base_.state); tor_fragile_assert(); return -1; } return 0; } /** Longest size for the relay payload of a RELAY_CONNECTED cell that we're * able to generate. */ /* 4 zero bytes; 1 type byte; 16 byte IPv6 address; 4 byte TTL. */ #define MAX_CONNECTED_CELL_PAYLOAD_LEN 25 /** Set the buffer at payload_out -- which must have at least * MAX_CONNECTED_CELL_PAYLOAD_LEN bytes available -- to the body of a * RELAY_CONNECTED cell indicating that we have connected to addr, and * that the name resolution that led us to addr will be valid for * ttl seconds. Return -1 on error, or the number of bytes used on * success. */ STATIC int connected_cell_format_payload(uint8_t *payload_out, const tor_addr_t *addr, uint32_t ttl) { const sa_family_t family = tor_addr_family(addr); int connected_payload_len; /* should be needless */ memset(payload_out, 0, MAX_CONNECTED_CELL_PAYLOAD_LEN); if (family == AF_INET) { set_uint32(payload_out, tor_addr_to_ipv4n(addr)); connected_payload_len = 4; } else if (family == AF_INET6) { set_uint32(payload_out, 0); set_uint8(payload_out + 4, 6); memcpy(payload_out + 5, tor_addr_to_in6_addr8(addr), 16); connected_payload_len = 21; } else { return -1; } set_uint32(payload_out + connected_payload_len, htonl(dns_clip_ttl(ttl))); connected_payload_len += 4; tor_assert(connected_payload_len <= MAX_CONNECTED_CELL_PAYLOAD_LEN); return connected_payload_len; } /** Connected handler for exit connections: start writing pending * data, deliver 'CONNECTED' relay cells as appropriate, and check * any pending data that may have been received. */ int connection_edge_finished_connecting(edge_connection_t *edge_conn) { connection_t *conn; tor_assert(edge_conn); tor_assert(edge_conn->base_.type == CONN_TYPE_EXIT); conn = TO_CONN(edge_conn); tor_assert(conn->state == EXIT_CONN_STATE_CONNECTING); log_info(LD_EXIT,"Exit connection to %s:%u (%s) established.", escaped_safe_str(conn->address), conn->port, safe_str(fmt_and_decorate_addr(&conn->addr))); rep_hist_note_exit_stream_opened(conn->port); conn->state = EXIT_CONN_STATE_OPEN; connection_watch_events(conn, READ_EVENT); /* stop writing, keep reading */ if (connection_get_outbuf_len(conn)) /* in case there are any queued relay * cells */ connection_start_writing(conn); /* deliver a 'connected' relay cell back through the circuit. */ if (connection_edge_is_rendezvous_stream(edge_conn)) { if (connection_edge_send_command(edge_conn, RELAY_COMMAND_CONNECTED, NULL, 0) < 0) return 0; /* circuit is closed, don't continue */ } else { uint8_t connected_payload[MAX_CONNECTED_CELL_PAYLOAD_LEN]; int connected_payload_len = connected_cell_format_payload(connected_payload, &conn->addr, edge_conn->address_ttl); if (connected_payload_len < 0) return -1; if (connection_edge_send_command(edge_conn, RELAY_COMMAND_CONNECTED, (char*)connected_payload, connected_payload_len) < 0) return 0; /* circuit is closed, don't continue */ } tor_assert(edge_conn->package_window > 0); /* in case the server has written anything */ return connection_edge_process_inbuf(edge_conn, 1); } /** A list of all the entry_connection_t * objects that are not marked * for close, and are in AP_CONN_STATE_CIRCUIT_WAIT. * * (Right now, we check in several places to make sure that this list is * correct. When it's incorrect, we'll fix it, and log a BUG message.) */ static smartlist_t *pending_entry_connections = NULL; static int untried_pending_connections = 0; /** * Mainloop event to tell us to scan for pending connections that can * be attached. */ static mainloop_event_t *attach_pending_entry_connections_ev = NULL; /** Common code to connection_(ap|exit)_about_to_close. */ static void connection_edge_about_to_close(edge_connection_t *edge_conn) { if (!edge_conn->edge_has_sent_end) { connection_t *conn = TO_CONN(edge_conn); log_warn(LD_BUG, "(Harmless.) Edge connection (marked at %s:%d) " "hasn't sent end yet?", conn->marked_for_close_file, conn->marked_for_close); tor_fragile_assert(); } } /** Called when we're about to finally unlink and free an AP (client) * connection: perform necessary accounting and cleanup */ void connection_ap_about_to_close(entry_connection_t *entry_conn) { circuit_t *circ; edge_connection_t *edge_conn = ENTRY_TO_EDGE_CONN(entry_conn); connection_t *conn = ENTRY_TO_CONN(entry_conn); connection_edge_about_to_close(edge_conn); if (entry_conn->socks_request->has_finished == 0) { /* since conn gets removed right after this function finishes, * there's no point trying to send back a reply at this point. */ log_warn(LD_BUG,"Closing stream (marked at %s:%d) without sending" " back a socks reply.", conn->marked_for_close_file, conn->marked_for_close); } if (!edge_conn->end_reason) { log_warn(LD_BUG,"Closing stream (marked at %s:%d) without having" " set end_reason.", conn->marked_for_close_file, conn->marked_for_close); } if (entry_conn->dns_server_request) { log_warn(LD_BUG,"Closing stream (marked at %s:%d) without having" " replied to DNS request.", conn->marked_for_close_file, conn->marked_for_close); dnsserv_reject_request(entry_conn); } if (TO_CONN(edge_conn)->state == AP_CONN_STATE_CIRCUIT_WAIT) { smartlist_remove(pending_entry_connections, entry_conn); } #if 1 /* Check to make sure that this isn't in pending_entry_connections if it * didn't actually belong there. */ if (TO_CONN(edge_conn)->type == CONN_TYPE_AP) { connection_ap_warn_and_unmark_if_pending_circ(entry_conn, "about_to_close"); } #endif /* 1 */ control_event_stream_bandwidth(edge_conn); control_event_stream_status(entry_conn, STREAM_EVENT_CLOSED, edge_conn->end_reason); circ = circuit_get_by_edge_conn(edge_conn); if (circ) circuit_detach_stream(circ, edge_conn); } /** Called when we're about to finally unlink and free an exit * connection: perform necessary accounting and cleanup */ void connection_exit_about_to_close(edge_connection_t *edge_conn) { circuit_t *circ; connection_t *conn = TO_CONN(edge_conn); connection_edge_about_to_close(edge_conn); circ = circuit_get_by_edge_conn(edge_conn); if (circ) circuit_detach_stream(circ, edge_conn); if (conn->state == EXIT_CONN_STATE_RESOLVING) { connection_dns_remove(edge_conn); } } /** Define a schedule for how long to wait between retrying * application connections. Rather than waiting a fixed amount of * time between each retry, we wait 10 seconds each for the first * two tries, and 15 seconds for each retry after * that. Hopefully this will improve the expected user experience. */ static int compute_retry_timeout(entry_connection_t *conn) { int timeout = get_options()->CircuitStreamTimeout; if (timeout) /* if our config options override the default, use them */ return timeout; if (conn->num_socks_retries < 2) /* try 0 and try 1 */ return 10; return 15; } /** Find all general-purpose AP streams waiting for a response that sent their * begin/resolve cell too long ago. Detach from their current circuit, and * mark their current circuit as unsuitable for new streams. Then call * connection_ap_handshake_attach_circuit() to attach to a new circuit (if * available) or launch a new one. * * For rendezvous streams, simply give up after SocksTimeout seconds (with no * retry attempt). */ void connection_ap_expire_beginning(void) { edge_connection_t *conn; entry_connection_t *entry_conn; circuit_t *circ; time_t now = time(NULL); const or_options_t *options = get_options(); int severity; int cutoff; int seconds_idle, seconds_since_born; smartlist_t *conns = get_connection_array(); SMARTLIST_FOREACH_BEGIN(conns, connection_t *, base_conn) { if (base_conn->type != CONN_TYPE_AP || base_conn->marked_for_close) continue; entry_conn = TO_ENTRY_CONN(base_conn); conn = ENTRY_TO_EDGE_CONN(entry_conn); /* if it's an internal linked connection, don't yell its status. */ severity = (tor_addr_is_null(&base_conn->addr) && !base_conn->port) ? LOG_INFO : LOG_NOTICE; seconds_idle = (int)( now - base_conn->timestamp_last_read_allowed ); seconds_since_born = (int)( now - base_conn->timestamp_created ); if (base_conn->state == AP_CONN_STATE_OPEN) continue; /* We already consider SocksTimeout in * connection_ap_handshake_attach_circuit(), but we need to consider * it here too because controllers that put streams in controller_wait * state never ask Tor to attach the circuit. */ if (AP_CONN_STATE_IS_UNATTACHED(base_conn->state)) { if (seconds_since_born >= options->SocksTimeout) { log_fn(severity, LD_APP, "Tried for %d seconds to get a connection to %s:%d. " "Giving up. (%s)", seconds_since_born, safe_str_client(entry_conn->socks_request->address), entry_conn->socks_request->port, conn_state_to_string(CONN_TYPE_AP, base_conn->state)); connection_mark_unattached_ap(entry_conn, END_STREAM_REASON_TIMEOUT); } continue; } /* We're in state connect_wait or resolve_wait now -- waiting for a * reply to our relay cell. See if we want to retry/give up. */ cutoff = compute_retry_timeout(entry_conn); if (seconds_idle < cutoff) continue; circ = circuit_get_by_edge_conn(conn); if (!circ) { /* it's vanished? */ log_info(LD_APP,"Conn is waiting (address %s), but lost its circ.", safe_str_client(entry_conn->socks_request->address)); connection_mark_unattached_ap(entry_conn, END_STREAM_REASON_TIMEOUT); continue; } if (circ->purpose == CIRCUIT_PURPOSE_C_REND_JOINED) { if (seconds_idle >= options->SocksTimeout) { log_fn(severity, LD_REND, "Rend stream is %d seconds late. Giving up on address" " '%s.onion'.", seconds_idle, safe_str_client(entry_conn->socks_request->address)); /* Roll back path bias use state so that we probe the circuit * if nothing else succeeds on it */ pathbias_mark_use_rollback(TO_ORIGIN_CIRCUIT(circ)); connection_edge_end(conn, END_STREAM_REASON_TIMEOUT); connection_mark_unattached_ap(entry_conn, END_STREAM_REASON_TIMEOUT); } continue; } if (circ->purpose != CIRCUIT_PURPOSE_C_GENERAL && circ->purpose != CIRCUIT_PURPOSE_C_HSDIR_GET && circ->purpose != CIRCUIT_PURPOSE_S_HSDIR_POST && circ->purpose != CIRCUIT_PURPOSE_C_MEASURE_TIMEOUT && circ->purpose != CIRCUIT_PURPOSE_PATH_BIAS_TESTING) { log_warn(LD_BUG, "circuit->purpose == CIRCUIT_PURPOSE_C_GENERAL failed. " "The purpose on the circuit was %s; it was in state %s, " "path_state %s.", circuit_purpose_to_string(circ->purpose), circuit_state_to_string(circ->state), CIRCUIT_IS_ORIGIN(circ) ? pathbias_state_to_string(TO_ORIGIN_CIRCUIT(circ)->path_state) : "none"); } log_fn(cutoff < 15 ? LOG_INFO : severity, LD_APP, "We tried for %d seconds to connect to '%s' using exit %s." " Retrying on a new circuit.", seconds_idle, safe_str_client(entry_conn->socks_request->address), conn->cpath_layer ? extend_info_describe(conn->cpath_layer->extend_info): "*unnamed*"); /* send an end down the circuit */ connection_edge_end(conn, END_STREAM_REASON_TIMEOUT); /* un-mark it as ending, since we're going to reuse it */ conn->edge_has_sent_end = 0; conn->end_reason = 0; /* make us not try this circuit again, but allow * current streams on it to survive if they can */ mark_circuit_unusable_for_new_conns(TO_ORIGIN_CIRCUIT(circ)); /* give our stream another 'cutoff' seconds to try */ conn->base_.timestamp_last_read_allowed += cutoff; if (entry_conn->num_socks_retries < 250) /* avoid overflow */ entry_conn->num_socks_retries++; /* move it back into 'pending' state, and try to attach. */ if (connection_ap_detach_retriable(entry_conn, TO_ORIGIN_CIRCUIT(circ), END_STREAM_REASON_TIMEOUT)<0) { if (!base_conn->marked_for_close) connection_mark_unattached_ap(entry_conn, END_STREAM_REASON_CANT_ATTACH); } } SMARTLIST_FOREACH_END(base_conn); } /** * As connection_ap_attach_pending, but first scans the entire connection * array to see if any elements are missing. */ void connection_ap_rescan_and_attach_pending(void) { entry_connection_t *entry_conn; smartlist_t *conns = get_connection_array(); if (PREDICT_UNLIKELY(NULL == pending_entry_connections)) pending_entry_connections = smartlist_new(); SMARTLIST_FOREACH_BEGIN(conns, connection_t *, conn) { if (conn->marked_for_close || conn->type != CONN_TYPE_AP || conn->state != AP_CONN_STATE_CIRCUIT_WAIT) continue; entry_conn = TO_ENTRY_CONN(conn); tor_assert(entry_conn); if (! smartlist_contains(pending_entry_connections, entry_conn)) { log_warn(LD_BUG, "Found a connection %p that was supposed to be " "in pending_entry_connections, but wasn't. No worries; " "adding it.", pending_entry_connections); untried_pending_connections = 1; connection_ap_mark_as_pending_circuit(entry_conn); } } SMARTLIST_FOREACH_END(conn); connection_ap_attach_pending(1); } #ifdef DEBUGGING_17659 #define UNMARK() do { \ entry_conn->marked_pending_circ_line = 0; \ entry_conn->marked_pending_circ_file = 0; \ } while (0) #else /* !(defined(DEBUGGING_17659)) */ #define UNMARK() do { } while (0) #endif /* defined(DEBUGGING_17659) */ /** Tell any AP streams that are listed as waiting for a new circuit to try * again. If there is an available circuit for a stream, attach it. Otherwise, * launch a new circuit. * * If retry is false, only check the list if it contains at least one * streams that we have not yet tried to attach to a circuit. */ void connection_ap_attach_pending(int retry) { if (PREDICT_UNLIKELY(!pending_entry_connections)) { return; } if (untried_pending_connections == 0 && !retry) return; /* Don't allow any modifications to list while we are iterating over * it. We'll put streams back on this list if we can't attach them * immediately. */ smartlist_t *pending = pending_entry_connections; pending_entry_connections = smartlist_new(); SMARTLIST_FOREACH_BEGIN(pending, entry_connection_t *, entry_conn) { connection_t *conn = ENTRY_TO_CONN(entry_conn); tor_assert(conn && entry_conn); if (conn->marked_for_close) { UNMARK(); continue; } if (conn->magic != ENTRY_CONNECTION_MAGIC) { log_warn(LD_BUG, "%p has impossible magic value %u.", entry_conn, (unsigned)conn->magic); UNMARK(); continue; } if (conn->state != AP_CONN_STATE_CIRCUIT_WAIT) { log_warn(LD_BUG, "%p is no longer in circuit_wait. Its current state " "is %s. Why is it on pending_entry_connections?", entry_conn, conn_state_to_string(conn->type, conn->state)); UNMARK(); continue; } /* Okay, we're through the sanity checks. Try to handle this stream. */ if (connection_ap_handshake_attach_circuit(entry_conn) < 0) { if (!conn->marked_for_close) connection_mark_unattached_ap(entry_conn, END_STREAM_REASON_CANT_ATTACH); } if (! conn->marked_for_close && conn->type == CONN_TYPE_AP && conn->state == AP_CONN_STATE_CIRCUIT_WAIT) { /* Is it still waiting for a circuit? If so, we didn't attach it, * so it's still pending. Put it back on the list. */ if (!smartlist_contains(pending_entry_connections, entry_conn)) { smartlist_add(pending_entry_connections, entry_conn); continue; } } /* If we got here, then we either closed the connection, or * we attached it. */ UNMARK(); } SMARTLIST_FOREACH_END(entry_conn); smartlist_free(pending); untried_pending_connections = 0; } static void attach_pending_entry_connections_cb(mainloop_event_t *ev, void *arg) { (void)ev; (void)arg; connection_ap_attach_pending(0); } /** Mark entry_conn as needing to get attached to a circuit. * * And entry_conn must be in AP_CONN_STATE_CIRCUIT_WAIT, * should not already be pending a circuit. The circuit will get * launched or the connection will get attached the next time we * call connection_ap_attach_pending(). */ void connection_ap_mark_as_pending_circuit_(entry_connection_t *entry_conn, const char *fname, int lineno) { connection_t *conn = ENTRY_TO_CONN(entry_conn); tor_assert(conn->state == AP_CONN_STATE_CIRCUIT_WAIT); tor_assert(conn->magic == ENTRY_CONNECTION_MAGIC); if (conn->marked_for_close) return; if (PREDICT_UNLIKELY(NULL == pending_entry_connections)) { pending_entry_connections = smartlist_new(); } if (PREDICT_UNLIKELY(NULL == attach_pending_entry_connections_ev)) { attach_pending_entry_connections_ev = mainloop_event_postloop_new( attach_pending_entry_connections_cb, NULL); } if (PREDICT_UNLIKELY(smartlist_contains(pending_entry_connections, entry_conn))) { log_warn(LD_BUG, "What?? pending_entry_connections already contains %p! " "(Called from %s:%d.)", entry_conn, fname, lineno); #ifdef DEBUGGING_17659 const char *f2 = entry_conn->marked_pending_circ_file; log_warn(LD_BUG, "(Previously called from %s:%d.)\n", f2 ? f2 : "", entry_conn->marked_pending_circ_line); #endif /* defined(DEBUGGING_17659) */ log_backtrace(LOG_WARN, LD_BUG, "To debug, this may help"); return; } #ifdef DEBUGGING_17659 entry_conn->marked_pending_circ_line = (uint16_t) lineno; entry_conn->marked_pending_circ_file = fname; #endif untried_pending_connections = 1; smartlist_add(pending_entry_connections, entry_conn); mainloop_event_activate(attach_pending_entry_connections_ev); } /** Mark entry_conn as no longer waiting for a circuit. */ void connection_ap_mark_as_non_pending_circuit(entry_connection_t *entry_conn) { if (PREDICT_UNLIKELY(NULL == pending_entry_connections)) return; UNMARK(); smartlist_remove(pending_entry_connections, entry_conn); } /* DOCDOC */ void connection_ap_warn_and_unmark_if_pending_circ(entry_connection_t *entry_conn, const char *where) { if (pending_entry_connections && smartlist_contains(pending_entry_connections, entry_conn)) { log_warn(LD_BUG, "What was %p doing in pending_entry_connections in %s?", entry_conn, where); connection_ap_mark_as_non_pending_circuit(entry_conn); } } /** Tell any AP streams that are waiting for a one-hop tunnel to * failed_digest that they are going to fail. */ /* XXXX We should get rid of this function, and instead attach * one-hop streams to circ->p_streams so they get marked in * circuit_mark_for_close like normal p_streams. */ void connection_ap_fail_onehop(const char *failed_digest, cpath_build_state_t *build_state) { entry_connection_t *entry_conn; char digest[DIGEST_LEN]; smartlist_t *conns = get_connection_array(); SMARTLIST_FOREACH_BEGIN(conns, connection_t *, conn) { if (conn->marked_for_close || conn->type != CONN_TYPE_AP || conn->state != AP_CONN_STATE_CIRCUIT_WAIT) continue; entry_conn = TO_ENTRY_CONN(conn); if (!entry_conn->want_onehop) continue; if (hexdigest_to_digest(entry_conn->chosen_exit_name, digest) < 0 || tor_memneq(digest, failed_digest, DIGEST_LEN)) continue; if (tor_digest_is_zero(digest)) { /* we don't know the digest; have to compare addr:port */ tor_addr_t addr; if (!build_state || !build_state->chosen_exit || !entry_conn->socks_request) { continue; } if (tor_addr_parse(&addr, entry_conn->socks_request->address)<0 || !tor_addr_eq(&build_state->chosen_exit->addr, &addr) || build_state->chosen_exit->port != entry_conn->socks_request->port) continue; } log_info(LD_APP, "Closing one-hop stream to '%s/%s' because the OR conn " "just failed.", entry_conn->chosen_exit_name, entry_conn->socks_request->address); connection_mark_unattached_ap(entry_conn, END_STREAM_REASON_TIMEOUT); } SMARTLIST_FOREACH_END(conn); } /** A circuit failed to finish on its last hop info. If there * are any streams waiting with this exit node in mind, but they * don't absolutely require it, make them give up on it. */ void circuit_discard_optional_exit_enclaves(extend_info_t *info) { entry_connection_t *entry_conn; const node_t *r1, *r2; smartlist_t *conns = get_connection_array(); SMARTLIST_FOREACH_BEGIN(conns, connection_t *, conn) { if (conn->marked_for_close || conn->type != CONN_TYPE_AP || conn->state != AP_CONN_STATE_CIRCUIT_WAIT) continue; entry_conn = TO_ENTRY_CONN(conn); if (!entry_conn->chosen_exit_optional && !entry_conn->chosen_exit_retries) continue; r1 = node_get_by_nickname(entry_conn->chosen_exit_name, NNF_NO_WARN_UNNAMED); r2 = node_get_by_id(info->identity_digest); if (!r1 || !r2 || r1 != r2) continue; tor_assert(entry_conn->socks_request); if (entry_conn->chosen_exit_optional) { log_info(LD_APP, "Giving up on enclave exit '%s' for destination %s.", safe_str_client(entry_conn->chosen_exit_name), escaped_safe_str_client(entry_conn->socks_request->address)); entry_conn->chosen_exit_optional = 0; tor_free(entry_conn->chosen_exit_name); /* clears it */ /* if this port is dangerous, warn or reject it now that we don't * think it'll be using an enclave. */ consider_plaintext_ports(entry_conn, entry_conn->socks_request->port); } if (entry_conn->chosen_exit_retries) { if (--entry_conn->chosen_exit_retries == 0) { /* give up! */ clear_trackexithost_mappings(entry_conn->chosen_exit_name); tor_free(entry_conn->chosen_exit_name); /* clears it */ /* if this port is dangerous, warn or reject it now that we don't * think it'll be using an enclave. */ consider_plaintext_ports(entry_conn, entry_conn->socks_request->port); } } } SMARTLIST_FOREACH_END(conn); } /** The AP connection conn has just failed while attaching or * sending a BEGIN or resolving on circ, but another circuit * might work. Detach the circuit, and either reattach it, launch a * new circuit, tell the controller, or give up as appropriate. * * Returns -1 on err, 1 on success, 0 on not-yet-sure. */ int connection_ap_detach_retriable(entry_connection_t *conn, origin_circuit_t *circ, int reason) { control_event_stream_status(conn, STREAM_EVENT_FAILED_RETRIABLE, reason); ENTRY_TO_CONN(conn)->timestamp_last_read_allowed = time(NULL); /* Roll back path bias use state so that we probe the circuit * if nothing else succeeds on it */ pathbias_mark_use_rollback(circ); if (conn->pending_optimistic_data) { buf_set_to_copy(&conn->sending_optimistic_data, conn->pending_optimistic_data); } if (!get_options()->LeaveStreamsUnattached || conn->use_begindir) { /* If we're attaching streams ourself, or if this connection is * a tunneled directory connection, then just attach it. */ ENTRY_TO_CONN(conn)->state = AP_CONN_STATE_CIRCUIT_WAIT; circuit_detach_stream(TO_CIRCUIT(circ),ENTRY_TO_EDGE_CONN(conn)); connection_ap_mark_as_pending_circuit(conn); } else { CONNECTION_AP_EXPECT_NONPENDING(conn); ENTRY_TO_CONN(conn)->state = AP_CONN_STATE_CONTROLLER_WAIT; circuit_detach_stream(TO_CIRCUIT(circ),ENTRY_TO_EDGE_CONN(conn)); } return 0; } /** Check if conn is using a dangerous port. Then warn and/or * reject depending on our config options. */ static int consider_plaintext_ports(entry_connection_t *conn, uint16_t port) { const or_options_t *options = get_options(); int reject = smartlist_contains_int_as_string( options->RejectPlaintextPorts, port); if (smartlist_contains_int_as_string(options->WarnPlaintextPorts, port)) { log_warn(LD_APP, "Application request to port %d: this port is " "commonly used for unencrypted protocols. Please make sure " "you don't send anything you would mind the rest of the " "Internet reading!%s", port, reject ? " Closing." : ""); control_event_client_status(LOG_WARN, "DANGEROUS_PORT PORT=%d RESULT=%s", port, reject ? "REJECT" : "WARN"); } if (reject) { log_info(LD_APP, "Port %d listed in RejectPlaintextPorts. Closing.", port); connection_mark_unattached_ap(conn, END_STREAM_REASON_ENTRYPOLICY); return -1; } return 0; } /** How many times do we try connecting with an exit configured via * TrackHostExits before concluding that it won't work any more and trying a * different one? */ #define TRACKHOSTEXITS_RETRIES 5 /** Call connection_ap_handshake_rewrite_and_attach() unless a controller * asked us to leave streams unattached. Return 0 in that case. * * See connection_ap_handshake_rewrite_and_attach()'s * documentation for arguments and return value. */ MOCK_IMPL(int, connection_ap_rewrite_and_attach_if_allowed,(entry_connection_t *conn, origin_circuit_t *circ, crypt_path_t *cpath)) { const or_options_t *options = get_options(); if (options->LeaveStreamsUnattached) { CONNECTION_AP_EXPECT_NONPENDING(conn); ENTRY_TO_CONN(conn)->state = AP_CONN_STATE_CONTROLLER_WAIT; return 0; } return connection_ap_handshake_rewrite_and_attach(conn, circ, cpath); } /* Try to perform any map-based rewriting of the target address in * conn, filling in the fields of out as we go, and modifying * conn->socks_request.address as appropriate. */ STATIC void connection_ap_handshake_rewrite(entry_connection_t *conn, rewrite_result_t *out) { socks_request_t *socks = conn->socks_request; const or_options_t *options = get_options(); tor_addr_t addr_tmp; /* Initialize all the fields of 'out' to reasonable defaults */ out->automap = 0; out->exit_source = ADDRMAPSRC_NONE; out->map_expires = TIME_MAX; out->end_reason = 0; out->should_close = 0; out->orig_address[0] = 0; /* We convert all incoming addresses to lowercase. */ tor_strlower(socks->address); /* Remember the original address. */ strlcpy(out->orig_address, socks->address, sizeof(out->orig_address)); log_debug(LD_APP,"Client asked for %s:%d", safe_str_client(socks->address), socks->port); /* Check for whether this is a .exit address. By default, those are * disallowed when they're coming straight from the client, but you're * allowed to have them in MapAddress commands and so forth. */ if (!strcmpend(socks->address, ".exit")) { log_warn(LD_APP, "The \".exit\" notation is disabled in Tor due to " "security risks."); control_event_client_status(LOG_WARN, "SOCKS_BAD_HOSTNAME HOSTNAME=%s", escaped(socks->address)); out->end_reason = END_STREAM_REASON_TORPROTOCOL; out->should_close = 1; return; } /* Remember the original address so we can tell the user about what * they actually said, not just what it turned into. */ /* XXX yes, this is the same as out->orig_address above. One is * in the output, and one is in the connection. */ if (! conn->original_dest_address) { /* Is the 'if' necessary here? XXXX */ conn->original_dest_address = tor_strdup(conn->socks_request->address); } /* First, apply MapAddress and MAPADDRESS mappings. We need to do * these only for non-reverse lookups, since they don't exist for those. * We also need to do this before we consider automapping, since we might * e.g. resolve irc.oftc.net into irconionaddress.onion, at which point * we'd need to automap it. */ if (socks->command != SOCKS_COMMAND_RESOLVE_PTR) { const unsigned rewrite_flags = AMR_FLAG_USE_MAPADDRESS; if (addressmap_rewrite(socks->address, sizeof(socks->address), rewrite_flags, &out->map_expires, &out->exit_source)) { control_event_stream_status(conn, STREAM_EVENT_REMAP, REMAP_STREAM_SOURCE_CACHE); } } /* Now see if we need to create or return an existing Hostname->IP * automapping. Automapping happens when we're asked to resolve a * hostname, and AutomapHostsOnResolve is set, and the hostname has a * suffix listed in AutomapHostsSuffixes. It's a handy feature * that lets you have Tor assign e.g. IPv6 addresses for .onion * names, and return them safely from DNSPort. */ if (socks->command == SOCKS_COMMAND_RESOLVE && tor_addr_parse(&addr_tmp, socks->address)<0 && options->AutomapHostsOnResolve) { /* Check the suffix... */ out->automap = addressmap_address_should_automap(socks->address, options); if (out->automap) { /* If we get here, then we should apply an automapping for this. */ const char *new_addr; /* We return an IPv4 address by default, or an IPv6 address if we * are allowed to do so. */ int addr_type = RESOLVED_TYPE_IPV4; if (conn->socks_request->socks_version != 4) { if (!conn->entry_cfg.ipv4_traffic || (conn->entry_cfg.ipv6_traffic && conn->entry_cfg.prefer_ipv6) || conn->entry_cfg.prefer_ipv6_virtaddr) addr_type = RESOLVED_TYPE_IPV6; } /* Okay, register the target address as automapped, and find the new * address we're supposed to give as a resolve answer. (Return a cached * value if we've looked up this address before. */ new_addr = addressmap_register_virtual_address( addr_type, tor_strdup(socks->address)); if (! new_addr) { log_warn(LD_APP, "Unable to automap address %s", escaped_safe_str(socks->address)); out->end_reason = END_STREAM_REASON_INTERNAL; out->should_close = 1; return; } log_info(LD_APP, "Automapping %s to %s", escaped_safe_str_client(socks->address), safe_str_client(new_addr)); strlcpy(socks->address, new_addr, sizeof(socks->address)); } } /* Now handle reverse lookups, if they're in the cache. This doesn't * happen too often, since client-side DNS caching is off by default, * and very deprecated. */ if (socks->command == SOCKS_COMMAND_RESOLVE_PTR) { unsigned rewrite_flags = 0; if (conn->entry_cfg.use_cached_ipv4_answers) rewrite_flags |= AMR_FLAG_USE_IPV4_DNS; if (conn->entry_cfg.use_cached_ipv6_answers) rewrite_flags |= AMR_FLAG_USE_IPV6_DNS; if (addressmap_rewrite_reverse(socks->address, sizeof(socks->address), rewrite_flags, &out->map_expires)) { char *result = tor_strdup(socks->address); /* remember _what_ is supposed to have been resolved. */ tor_snprintf(socks->address, sizeof(socks->address), "REVERSE[%s]", out->orig_address); connection_ap_handshake_socks_resolved(conn, RESOLVED_TYPE_HOSTNAME, strlen(result), (uint8_t*)result, -1, out->map_expires); tor_free(result); out->end_reason = END_STREAM_REASON_DONE | END_STREAM_REASON_FLAG_ALREADY_SOCKS_REPLIED; out->should_close = 1; return; } /* Hang on, did we find an answer saying that this is a reverse lookup for * an internal address? If so, we should reject it if we're configured to * do so. */ if (options->ClientDNSRejectInternalAddresses) { /* Don't let clients try to do a reverse lookup on 10.0.0.1. */ tor_addr_t addr; int ok; ok = tor_addr_parse_PTR_name( &addr, socks->address, AF_UNSPEC, 1); if (ok == 1 && tor_addr_is_internal(&addr, 0)) { connection_ap_handshake_socks_resolved(conn, RESOLVED_TYPE_ERROR, 0, NULL, -1, TIME_MAX); out->end_reason = END_STREAM_REASON_SOCKSPROTOCOL | END_STREAM_REASON_FLAG_ALREADY_SOCKS_REPLIED; out->should_close = 1; return; } } } /* If we didn't automap it before, then this is still the address that * came straight from the user, mapped according to any * MapAddress/MAPADDRESS commands. Now apply other mappings, * including previously registered Automap entries (IP back to * hostname), TrackHostExits entries, and client-side DNS cache * entries (if they're turned on). */ if (socks->command != SOCKS_COMMAND_RESOLVE_PTR && !out->automap) { unsigned rewrite_flags = AMR_FLAG_USE_AUTOMAP | AMR_FLAG_USE_TRACKEXIT; addressmap_entry_source_t exit_source2; if (conn->entry_cfg.use_cached_ipv4_answers) rewrite_flags |= AMR_FLAG_USE_IPV4_DNS; if (conn->entry_cfg.use_cached_ipv6_answers) rewrite_flags |= AMR_FLAG_USE_IPV6_DNS; if (addressmap_rewrite(socks->address, sizeof(socks->address), rewrite_flags, &out->map_expires, &exit_source2)) { control_event_stream_status(conn, STREAM_EVENT_REMAP, REMAP_STREAM_SOURCE_CACHE); } if (out->exit_source == ADDRMAPSRC_NONE) { /* If it wasn't a .exit before, maybe it turned into a .exit. Remember * the original source of a .exit. */ out->exit_source = exit_source2; } } /* Check to see whether we're about to use an address in the virtual * range without actually having gotten it from an Automap. */ if (!out->automap && address_is_in_virtual_range(socks->address)) { /* This address was probably handed out by * client_dns_get_unmapped_address, but the mapping was discarded for some * reason. Or the user typed in a virtual address range manually. We * *don't* want to send the address through Tor; that's likely to fail, * and may leak information. */ log_warn(LD_APP,"Missing mapping for virtual address '%s'. Refusing.", safe_str_client(socks->address)); out->end_reason = END_STREAM_REASON_INTERNAL; out->should_close = 1; return; } } /** We just received a SOCKS request in conn to an onion address of type * addresstype. Start connecting to the onion service. */ static int connection_ap_handle_onion(entry_connection_t *conn, socks_request_t *socks, origin_circuit_t *circ, hostname_type_t addresstype) { time_t now = approx_time(); connection_t *base_conn = ENTRY_TO_CONN(conn); /* If .onion address requests are disabled, refuse the request */ if (!conn->entry_cfg.onion_traffic) { log_warn(LD_APP, "Onion address %s requested from a port with .onion " "disabled", safe_str_client(socks->address)); connection_mark_unattached_ap(conn, END_STREAM_REASON_ENTRYPOLICY); return -1; } /* Check whether it's RESOLVE or RESOLVE_PTR. We don't handle those * for hidden service addresses. */ if (SOCKS_COMMAND_IS_RESOLVE(socks->command)) { /* if it's a resolve request, fail it right now, rather than * building all the circuits and then realizing it won't work. */ log_warn(LD_APP, "Resolve requests to hidden services not allowed. Failing."); connection_ap_handshake_socks_resolved(conn,RESOLVED_TYPE_ERROR, 0,NULL,-1,TIME_MAX); connection_mark_unattached_ap(conn, END_STREAM_REASON_SOCKSPROTOCOL | END_STREAM_REASON_FLAG_ALREADY_SOCKS_REPLIED); return -1; } /* If we were passed a circuit, then we need to fail. .onion addresses * only work when we launch our own circuits for now. */ if (circ) { log_warn(LD_CONTROL, "Attachstream to a circuit is not " "supported for .onion addresses currently. Failing."); connection_mark_unattached_ap(conn, END_STREAM_REASON_TORPROTOCOL); return -1; } /* Interface: Regardless of HS version after the block below we should have set onion_address, rend_cache_lookup_result, and descriptor_is_usable. */ const char *onion_address = NULL; int rend_cache_lookup_result = -ENOENT; int descriptor_is_usable = 0; if (addresstype == ONION_V2_HOSTNAME) { /* it's a v2 hidden service */ rend_cache_entry_t *entry = NULL; /* Look up if we have client authorization configured for this hidden * service. If we do, associate it with the rend_data. */ rend_service_authorization_t *client_auth = rend_client_lookup_service_authorization(socks->address); const uint8_t *cookie = NULL; rend_auth_type_t auth_type = REND_NO_AUTH; if (client_auth) { log_info(LD_REND, "Using previously configured client authorization " "for hidden service request."); auth_type = client_auth->auth_type; cookie = client_auth->descriptor_cookie; } /* Fill in the rend_data field so we can start doing a connection to * a hidden service. */ rend_data_t *rend_data = ENTRY_TO_EDGE_CONN(conn)->rend_data = rend_data_client_create(socks->address, NULL, (char *) cookie, auth_type); if (rend_data == NULL) { return -1; } onion_address = rend_data_get_address(rend_data); log_info(LD_REND,"Got a hidden service request for ID '%s'", safe_str_client(onion_address)); rend_cache_lookup_result = rend_cache_lookup_entry(onion_address,-1, &entry); if (!rend_cache_lookup_result && entry) { descriptor_is_usable = rend_client_any_intro_points_usable(entry); } } else { /* it's a v3 hidden service */ tor_assert(addresstype == ONION_V3_HOSTNAME); const hs_descriptor_t *cached_desc = NULL; int retval; /* Create HS conn identifier with HS pubkey */ hs_ident_edge_conn_t *hs_conn_ident = tor_malloc_zero(sizeof(hs_ident_edge_conn_t)); retval = hs_parse_address(socks->address, &hs_conn_ident->identity_pk, NULL, NULL); if (retval < 0) { log_warn(LD_GENERAL, "failed to parse hs address"); tor_free(hs_conn_ident); return -1; } ENTRY_TO_EDGE_CONN(conn)->hs_ident = hs_conn_ident; onion_address = socks->address; /* Check the v3 desc cache */ cached_desc = hs_cache_lookup_as_client(&hs_conn_ident->identity_pk); if (cached_desc) { rend_cache_lookup_result = 0; descriptor_is_usable = hs_client_any_intro_points_usable(&hs_conn_ident->identity_pk, cached_desc); log_info(LD_GENERAL, "Found %s descriptor in cache for %s. %s.", (descriptor_is_usable) ? "usable" : "unusable", safe_str_client(onion_address), (descriptor_is_usable) ? "Not fetching." : "Refecting."); } else { rend_cache_lookup_result = -ENOENT; } } /* Lookup the given onion address. If invalid, stop right now. * Otherwise, we might have it in the cache or not. */ unsigned int refetch_desc = 0; if (rend_cache_lookup_result < 0) { switch (-rend_cache_lookup_result) { case EINVAL: /* We should already have rejected this address! */ log_warn(LD_BUG,"Invalid service name '%s'", safe_str_client(onion_address)); connection_mark_unattached_ap(conn, END_STREAM_REASON_TORPROTOCOL); return -1; case ENOENT: /* We didn't have this; we should look it up. */ log_info(LD_REND, "No descriptor found in our cache for %s. Fetching.", safe_str_client(onion_address)); refetch_desc = 1; break; default: log_warn(LD_BUG, "Unknown cache lookup error %d", rend_cache_lookup_result); return -1; } } /* Help predict that we'll want to do hidden service circuits in the * future. We're not sure if it will need a stable circuit yet, but * we know we'll need *something*. */ rep_hist_note_used_internal(now, 0, 1); /* Now we have a descriptor but is it usable or not? If not, refetch. * Also, a fetch could have been requested if the onion address was not * found in the cache previously. */ if (refetch_desc || !descriptor_is_usable) { edge_connection_t *edge_conn = ENTRY_TO_EDGE_CONN(conn); connection_ap_mark_as_non_pending_circuit(conn); base_conn->state = AP_CONN_STATE_RENDDESC_WAIT; if (addresstype == ONION_V2_HOSTNAME) { tor_assert(edge_conn->rend_data); rend_client_refetch_v2_renddesc(edge_conn->rend_data); /* Whatever the result of the refetch, we don't go further. */ return 0; } else { tor_assert(addresstype == ONION_V3_HOSTNAME); tor_assert(edge_conn->hs_ident); /* Attempt to fetch the hsv3 descriptor. Check the retval to see how it * went and act accordingly. */ int ret = hs_client_refetch_hsdesc(&edge_conn->hs_ident->identity_pk); switch (ret) { case HS_CLIENT_FETCH_MISSING_INFO: /* Keeping the connection in descriptor wait state is fine because * once we get enough dirinfo or a new live consensus, the HS client * subsystem is notified and every connection in that state will * trigger a fetch for the service key. */ case HS_CLIENT_FETCH_LAUNCHED: case HS_CLIENT_FETCH_PENDING: case HS_CLIENT_FETCH_HAVE_DESC: return 0; case HS_CLIENT_FETCH_ERROR: case HS_CLIENT_FETCH_NO_HSDIRS: case HS_CLIENT_FETCH_NOT_ALLOWED: /* Can't proceed further and better close the SOCKS request. */ return -1; } } } /* We have the descriptor! So launch a connection to the HS. */ log_info(LD_REND, "Descriptor is here. Great."); base_conn->state = AP_CONN_STATE_CIRCUIT_WAIT; /* We'll try to attach it at the next event loop, or whenever * we call connection_ap_attach_pending() */ connection_ap_mark_as_pending_circuit(conn); return 0; } /** Connection conn just finished its socks handshake, or the * controller asked us to take care of it. If circ is defined, * then that's where we'll want to attach it. Otherwise we have to * figure it out ourselves. * * First, parse whether it's a .exit address, remap it, and so on. Then * if it's for a general circuit, try to attach it to a circuit (or launch * one as needed), else if it's for a rendezvous circuit, fetch a * rendezvous descriptor first (or attach/launch a circuit if the * rendezvous descriptor is already here and fresh enough). * * The stream will exit from the hop * indicated by cpath, or from the last hop in circ's cpath if * cpath is NULL. */ int connection_ap_handshake_rewrite_and_attach(entry_connection_t *conn, origin_circuit_t *circ, crypt_path_t *cpath) { socks_request_t *socks = conn->socks_request; const or_options_t *options = get_options(); connection_t *base_conn = ENTRY_TO_CONN(conn); time_t now = time(NULL); rewrite_result_t rr; /* First we'll do the rewrite part. Let's see if we get a reasonable * answer. */ memset(&rr, 0, sizeof(rr)); connection_ap_handshake_rewrite(conn,&rr); if (rr.should_close) { /* connection_ap_handshake_rewrite told us to close the connection: * either because it sent back an answer, or because it sent back an * error */ connection_mark_unattached_ap(conn, rr.end_reason); if (END_STREAM_REASON_DONE == (rr.end_reason & END_STREAM_REASON_MASK)) return 0; else return -1; } const time_t map_expires = rr.map_expires; const int automap = rr.automap; const addressmap_entry_source_t exit_source = rr.exit_source; /* Now, we parse the address to see if it's an .onion or .exit or * other special address. */ const hostname_type_t addresstype = parse_extended_hostname(socks->address); /* Now see whether the hostname is bogus. This could happen because of an * onion hostname whose format we don't recognize. */ if (addresstype == BAD_HOSTNAME) { control_event_client_status(LOG_WARN, "SOCKS_BAD_HOSTNAME HOSTNAME=%s", escaped(socks->address)); connection_mark_unattached_ap(conn, END_STREAM_REASON_TORPROTOCOL); return -1; } /* If this is a .exit hostname, strip off the .name.exit part, and * see whether we're willing to connect there, and and otherwise handle the * .exit address. * * We'll set chosen_exit_name and/or close the connection as appropriate. */ if (addresstype == EXIT_HOSTNAME) { /* If StrictNodes is not set, then .exit overrides ExcludeNodes but * not ExcludeExitNodes. */ routerset_t *excludeset = options->StrictNodes ? options->ExcludeExitNodesUnion_ : options->ExcludeExitNodes; const node_t *node = NULL; /* If this .exit was added by an AUTOMAP, then it came straight from * a user. That's not safe. */ if (exit_source == ADDRMAPSRC_AUTOMAP) { /* Whoops; this one is stale. It must have gotten added earlier? * (Probably this is not possible, since AllowDotExit no longer * exists.) */ log_warn(LD_APP,"Stale automapped address for '%s.exit'. Refusing.", safe_str_client(socks->address)); control_event_client_status(LOG_WARN, "SOCKS_BAD_HOSTNAME HOSTNAME=%s", escaped(socks->address)); connection_mark_unattached_ap(conn, END_STREAM_REASON_TORPROTOCOL); tor_assert_nonfatal_unreached(); return -1; } /* Double-check to make sure there are no .exits coming from * impossible/weird sources. */ if (exit_source == ADDRMAPSRC_DNS || exit_source == ADDRMAPSRC_NONE) { /* It shouldn't be possible to get a .exit address from any of these * sources. */ log_warn(LD_BUG,"Address '%s.exit', with impossible source for the " ".exit part. Refusing.", safe_str_client(socks->address)); control_event_client_status(LOG_WARN, "SOCKS_BAD_HOSTNAME HOSTNAME=%s", escaped(socks->address)); connection_mark_unattached_ap(conn, END_STREAM_REASON_TORPROTOCOL); return -1; } tor_assert(!automap); /* Now, find the character before the .(name) part. * (The ".exit" part got stripped off by "parse_extended_hostname"). * * We're going to put the exit name into conn->chosen_exit_name, and * look up a node correspondingly. */ char *s = strrchr(socks->address,'.'); if (s) { /* The address was of the form "(stuff).(name).exit */ if (s[1] != '\0') { /* Looks like a real .exit one. */ conn->chosen_exit_name = tor_strdup(s+1); node = node_get_by_nickname(conn->chosen_exit_name, 0); if (exit_source == ADDRMAPSRC_TRACKEXIT) { /* We 5 tries before it expires the addressmap */ conn->chosen_exit_retries = TRACKHOSTEXITS_RETRIES; } *s = 0; } else { /* Oops, the address was (stuff)..exit. That's not okay. */ log_warn(LD_APP,"Malformed exit address '%s.exit'. Refusing.", safe_str_client(socks->address)); control_event_client_status(LOG_WARN, "SOCKS_BAD_HOSTNAME HOSTNAME=%s", escaped(socks->address)); connection_mark_unattached_ap(conn, END_STREAM_REASON_TORPROTOCOL); return -1; } } else { /* It looks like they just asked for "foo.exit". That's a special * form that means (foo's address).foo.exit. */ conn->chosen_exit_name = tor_strdup(socks->address); node = node_get_by_nickname(conn->chosen_exit_name, 0); if (node) { *socks->address = 0; node_get_address_string(node, socks->address, sizeof(socks->address)); } } /* Now make sure that the chosen exit exists... */ if (!node) { log_warn(LD_APP, "Unrecognized relay in exit address '%s.exit'. Refusing.", safe_str_client(socks->address)); connection_mark_unattached_ap(conn, END_STREAM_REASON_TORPROTOCOL); return -1; } /* ...and make sure that it isn't excluded. */ if (routerset_contains_node(excludeset, node)) { log_warn(LD_APP, "Excluded relay in exit address '%s.exit'. Refusing.", safe_str_client(socks->address)); connection_mark_unattached_ap(conn, END_STREAM_REASON_TORPROTOCOL); return -1; } /* XXXX-1090 Should we also allow foo.bar.exit if ExitNodes is set and Bar is not listed in it? I say yes, but our revised manpage branch implies no. */ } /* Now, we handle everything that isn't a .onion address. */ if (addresstype != ONION_V2_HOSTNAME && addresstype != ONION_V3_HOSTNAME) { /* Not a hidden-service request. It's either a hostname or an IP, * possibly with a .exit that we stripped off. We're going to check * if we're allowed to connect/resolve there, and then launch the * appropriate request. */ /* Check for funny characters in the address. */ if (address_is_invalid_destination(socks->address, 1)) { control_event_client_status(LOG_WARN, "SOCKS_BAD_HOSTNAME HOSTNAME=%s", escaped(socks->address)); log_warn(LD_APP, "Destination '%s' seems to be an invalid hostname. Failing.", safe_str_client(socks->address)); connection_mark_unattached_ap(conn, END_STREAM_REASON_TORPROTOCOL); return -1; } #ifdef ENABLE_TOR2WEB_MODE /* If we're running in Tor2webMode, we don't allow anything BUT .onion * addresses. */ if (options->Tor2webMode) { log_warn(LD_APP, "Refusing to connect to non-hidden-service hostname " "or IP address %s because tor2web mode is enabled.", safe_str_client(socks->address)); connection_mark_unattached_ap(conn, END_STREAM_REASON_ENTRYPOLICY); return -1; } #endif /* defined(ENABLE_TOR2WEB_MODE) */ /* socks->address is a non-onion hostname or IP address. * If we can't do any non-onion requests, refuse the connection. * If we have a hostname but can't do DNS, refuse the connection. * If we have an IP address, but we can't use that address family, * refuse the connection. * * If we can do DNS requests, and we can use at least one address family, * then we have to resolve the address first. Then we'll know if it * resolves to a usable address family. */ /* First, check if all non-onion traffic is disabled */ if (!conn->entry_cfg.dns_request && !conn->entry_cfg.ipv4_traffic && !conn->entry_cfg.ipv6_traffic) { log_warn(LD_APP, "Refusing to connect to non-hidden-service hostname " "or IP address %s because Port has OnionTrafficOnly set (or " "NoDNSRequest, NoIPv4Traffic, and NoIPv6Traffic).", safe_str_client(socks->address)); connection_mark_unattached_ap(conn, END_STREAM_REASON_ENTRYPOLICY); return -1; } /* Then check if we have a hostname or IP address, and whether DNS or * the IP address family are permitted. Reject if not. */ tor_addr_t dummy_addr; int socks_family = tor_addr_parse(&dummy_addr, socks->address); /* family will be -1 for a non-onion hostname that's not an IP */ if (socks_family == -1) { if (!conn->entry_cfg.dns_request) { log_warn(LD_APP, "Refusing to connect to hostname %s " "because Port has NoDNSRequest set.", safe_str_client(socks->address)); connection_mark_unattached_ap(conn, END_STREAM_REASON_ENTRYPOLICY); return -1; } } else if (socks_family == AF_INET) { if (!conn->entry_cfg.ipv4_traffic) { log_warn(LD_APP, "Refusing to connect to IPv4 address %s because " "Port has NoIPv4Traffic set.", safe_str_client(socks->address)); connection_mark_unattached_ap(conn, END_STREAM_REASON_ENTRYPOLICY); return -1; } } else if (socks_family == AF_INET6) { if (!conn->entry_cfg.ipv6_traffic) { log_warn(LD_APP, "Refusing to connect to IPv6 address %s because " "Port has NoIPv6Traffic set.", safe_str_client(socks->address)); connection_mark_unattached_ap(conn, END_STREAM_REASON_ENTRYPOLICY); return -1; } } else { tor_assert_nonfatal_unreached_once(); } /* See if this is a hostname lookup that we can answer immediately. * (For example, an attempt to look up the IP address for an IP address.) */ if (socks->command == SOCKS_COMMAND_RESOLVE) { tor_addr_t answer; /* Reply to resolves immediately if we can. */ if (tor_addr_parse(&answer, socks->address) >= 0) {/* is it an IP? */ /* remember _what_ is supposed to have been resolved. */ strlcpy(socks->address, rr.orig_address, sizeof(socks->address)); connection_ap_handshake_socks_resolved_addr(conn, &answer, -1, map_expires); connection_mark_unattached_ap(conn, END_STREAM_REASON_DONE | END_STREAM_REASON_FLAG_ALREADY_SOCKS_REPLIED); return 0; } tor_assert(!automap); rep_hist_note_used_resolve(now); /* help predict this next time */ } else if (socks->command == SOCKS_COMMAND_CONNECT) { /* Now see if this is a connect request that we can reject immediately */ tor_assert(!automap); /* Don't allow connections to port 0. */ if (socks->port == 0) { log_notice(LD_APP,"Application asked to connect to port 0. Refusing."); connection_mark_unattached_ap(conn, END_STREAM_REASON_TORPROTOCOL); return -1; } /* You can't make connections to internal addresses, by default. * Exceptions are begindir requests (where the address is meaningless), * or cases where you've hand-configured a particular exit, thereby * making the local address meaningful. */ if (options->ClientRejectInternalAddresses && !conn->use_begindir && !conn->chosen_exit_name && !circ) { /* If we reach this point then we don't want to allow internal * addresses. Check if we got one. */ tor_addr_t addr; if (tor_addr_hostname_is_local(socks->address) || (tor_addr_parse(&addr, socks->address) >= 0 && tor_addr_is_internal(&addr, 0))) { /* If this is an explicit private address with no chosen exit node, * then we really don't want to try to connect to it. That's * probably an error. */ if (conn->is_transparent_ap) { #define WARN_INTRVL_LOOP 300 static ratelim_t loop_warn_limit = RATELIM_INIT(WARN_INTRVL_LOOP); char *m; if ((m = rate_limit_log(&loop_warn_limit, approx_time()))) { log_warn(LD_NET, "Rejecting request for anonymous connection to private " "address %s on a TransPort or NATDPort. Possible loop " "in your NAT rules?%s", safe_str_client(socks->address), m); tor_free(m); } } else { #define WARN_INTRVL_PRIV 300 static ratelim_t priv_warn_limit = RATELIM_INIT(WARN_INTRVL_PRIV); char *m; if ((m = rate_limit_log(&priv_warn_limit, approx_time()))) { log_warn(LD_NET, "Rejecting SOCKS request for anonymous connection to " "private address %s.%s", safe_str_client(socks->address),m); tor_free(m); } } connection_mark_unattached_ap(conn, END_STREAM_REASON_PRIVATE_ADDR); return -1; } } /* end "if we should check for internal addresses" */ /* Okay. We're still doing a CONNECT, and it wasn't a private * address. Here we do special handling for literal IP addresses, * to see if we should reject this preemptively, and to set up * fields in conn->entry_cfg to tell the exit what AF we want. */ { tor_addr_t addr; /* XXX Duplicate call to tor_addr_parse. */ if (tor_addr_parse(&addr, socks->address) >= 0) { /* If we reach this point, it's an IPv4 or an IPv6 address. */ sa_family_t family = tor_addr_family(&addr); if ((family == AF_INET && ! conn->entry_cfg.ipv4_traffic) || (family == AF_INET6 && ! conn->entry_cfg.ipv6_traffic)) { /* You can't do an IPv4 address on a v6-only socks listener, * or vice versa. */ log_warn(LD_NET, "Rejecting SOCKS request for an IP address " "family that this listener does not support."); connection_mark_unattached_ap(conn, END_STREAM_REASON_ENTRYPOLICY); return -1; } else if (family == AF_INET6 && socks->socks_version == 4) { /* You can't make a socks4 request to an IPv6 address. Socks4 * doesn't support that. */ log_warn(LD_NET, "Rejecting SOCKS4 request for an IPv6 address."); connection_mark_unattached_ap(conn, END_STREAM_REASON_ENTRYPOLICY); return -1; } else if (socks->socks_version == 4 && !conn->entry_cfg.ipv4_traffic) { /* You can't do any kind of Socks4 request when IPv4 is forbidden. * * XXX raise this check outside the enclosing block? */ log_warn(LD_NET, "Rejecting SOCKS4 request on a listener with " "no IPv4 traffic supported."); connection_mark_unattached_ap(conn, END_STREAM_REASON_ENTRYPOLICY); return -1; } else if (family == AF_INET6) { /* Tell the exit: we won't accept any ipv4 connection to an IPv6 * address. */ conn->entry_cfg.ipv4_traffic = 0; } else if (family == AF_INET) { /* Tell the exit: we won't accept any ipv6 connection to an IPv4 * address. */ conn->entry_cfg.ipv6_traffic = 0; } } } /* we never allow IPv6 answers on socks4. (TODO: Is this smart?) */ if (socks->socks_version == 4) conn->entry_cfg.ipv6_traffic = 0; /* Still handling CONNECT. Now, check for exit enclaves. (Which we * don't do on BEGIN_DIR, or when there is a chosen exit.) * * TODO: Should we remove this? Exit enclaves are nutty and don't * work very well */ if (!conn->use_begindir && !conn->chosen_exit_name && !circ) { /* see if we can find a suitable enclave exit */ const node_t *r = router_find_exact_exit_enclave(socks->address, socks->port); if (r) { log_info(LD_APP, "Redirecting address %s to exit at enclave router %s", safe_str_client(socks->address), node_describe(r)); /* use the hex digest, not nickname, in case there are two routers with this nickname */ conn->chosen_exit_name = tor_strdup(hex_str(r->identity, DIGEST_LEN)); conn->chosen_exit_optional = 1; } } /* Still handling CONNECT: warn or reject if it's using a dangerous * port. */ if (!conn->use_begindir && !conn->chosen_exit_name && !circ) if (consider_plaintext_ports(conn, socks->port) < 0) return -1; /* Remember the port so that we will predict that more requests there will happen in the future. */ if (!conn->use_begindir) { /* help predict this next time */ rep_hist_note_used_port(now, socks->port); } } else if (socks->command == SOCKS_COMMAND_RESOLVE_PTR) { rep_hist_note_used_resolve(now); /* help predict this next time */ /* no extra processing needed */ } else { /* We should only be doing CONNECT, RESOLVE, or RESOLVE_PTR! */ tor_fragile_assert(); } /* Okay. At this point we've set chosen_exit_name if needed, rewritten the * address, and decided not to reject it for any number of reasons. Now * mark the connection as waiting for a circuit, and try to attach it! */ base_conn->state = AP_CONN_STATE_CIRCUIT_WAIT; /* If we were given a circuit to attach to, try to attach. Otherwise, * try to find a good one and attach to that. */ int rv; if (circ) { rv = connection_ap_handshake_attach_chosen_circuit(conn, circ, cpath); } else { /* We'll try to attach it at the next event loop, or whenever * we call connection_ap_attach_pending() */ connection_ap_mark_as_pending_circuit(conn); rv = 0; } /* If the above function returned 0 then we're waiting for a circuit. * if it returned 1, we're attached. Both are okay. But if it returned * -1, there was an error, so make sure the connection is marked, and * return -1. */ if (rv < 0) { if (!base_conn->marked_for_close) connection_mark_unattached_ap(conn, END_STREAM_REASON_CANT_ATTACH); return -1; } return 0; } else { /* If we get here, it's a request for a .onion address! */ tor_assert(addresstype == ONION_V2_HOSTNAME || addresstype == ONION_V3_HOSTNAME); tor_assert(!automap); return connection_ap_handle_onion(conn, socks, circ, addresstype); } return 0; /* unreached but keeps the compiler happy */ } #ifdef TRANS_PF static int pf_socket = -1; int get_pf_socket(void) { int pf; /* This should be opened before dropping privileges. */ if (pf_socket >= 0) return pf_socket; #if defined(OpenBSD) /* only works on OpenBSD */ pf = tor_open_cloexec("/dev/pf", O_RDONLY, 0); #else /* works on NetBSD and FreeBSD */ pf = tor_open_cloexec("/dev/pf", O_RDWR, 0); #endif /* defined(OpenBSD) */ if (pf < 0) { log_warn(LD_NET, "open(\"/dev/pf\") failed: %s", strerror(errno)); return -1; } pf_socket = pf; return pf_socket; } #endif /* defined(TRANS_PF) */ #if defined(TRANS_NETFILTER) || defined(TRANS_PF) || \ defined(TRANS_TPROXY) /** Try fill in the address of req from the socket configured * with conn. */ static int destination_from_socket(entry_connection_t *conn, socks_request_t *req) { struct sockaddr_storage orig_dst; socklen_t orig_dst_len = sizeof(orig_dst); tor_addr_t addr; #ifdef TRANS_TPROXY if (get_options()->TransProxyType_parsed == TPT_TPROXY) { if (getsockname(ENTRY_TO_CONN(conn)->s, (struct sockaddr*)&orig_dst, &orig_dst_len) < 0) { int e = tor_socket_errno(ENTRY_TO_CONN(conn)->s); log_warn(LD_NET, "getsockname() failed: %s", tor_socket_strerror(e)); return -1; } goto done; } #endif /* defined(TRANS_TPROXY) */ #ifdef TRANS_NETFILTER int rv = -1; switch (ENTRY_TO_CONN(conn)->socket_family) { #ifdef TRANS_NETFILTER_IPV4 case AF_INET: rv = getsockopt(ENTRY_TO_CONN(conn)->s, SOL_IP, SO_ORIGINAL_DST, (struct sockaddr*)&orig_dst, &orig_dst_len); break; #endif /* defined(TRANS_NETFILTER_IPV4) */ #ifdef TRANS_NETFILTER_IPV6 case AF_INET6: rv = getsockopt(ENTRY_TO_CONN(conn)->s, SOL_IPV6, IP6T_SO_ORIGINAL_DST, (struct sockaddr*)&orig_dst, &orig_dst_len); break; #endif /* defined(TRANS_NETFILTER_IPV6) */ default: log_warn(LD_BUG, "Received transparent data from an unsuported socket family %d", ENTRY_TO_CONN(conn)->socket_family); return -1; } if (rv < 0) { int e = tor_socket_errno(ENTRY_TO_CONN(conn)->s); log_warn(LD_NET, "getsockopt() failed: %s", tor_socket_strerror(e)); return -1; } goto done; #elif defined(TRANS_PF) if (getsockname(ENTRY_TO_CONN(conn)->s, (struct sockaddr*)&orig_dst, &orig_dst_len) < 0) { int e = tor_socket_errno(ENTRY_TO_CONN(conn)->s); log_warn(LD_NET, "getsockname() failed: %s", tor_socket_strerror(e)); return -1; } goto done; #else (void)conn; (void)req; log_warn(LD_BUG, "Unable to determine destination from socket."); return -1; #endif /* defined(TRANS_NETFILTER) || ... */ done: tor_addr_from_sockaddr(&addr, (struct sockaddr*)&orig_dst, &req->port); tor_addr_to_str(req->address, &addr, sizeof(req->address), 1); return 0; } #endif /* defined(TRANS_NETFILTER) || defined(TRANS_PF) || ... */ #ifdef TRANS_PF static int destination_from_pf(entry_connection_t *conn, socks_request_t *req) { struct sockaddr_storage proxy_addr; socklen_t proxy_addr_len = sizeof(proxy_addr); struct sockaddr *proxy_sa = (struct sockaddr*) &proxy_addr; struct pfioc_natlook pnl; tor_addr_t addr; int pf = -1; if (getsockname(ENTRY_TO_CONN(conn)->s, (struct sockaddr*)&proxy_addr, &proxy_addr_len) < 0) { int e = tor_socket_errno(ENTRY_TO_CONN(conn)->s); log_warn(LD_NET, "getsockname() to determine transocks destination " "failed: %s", tor_socket_strerror(e)); return -1; } #ifdef __FreeBSD__ if (get_options()->TransProxyType_parsed == TPT_IPFW) { /* ipfw(8) is used and in this case getsockname returned the original destination */ if (tor_addr_from_sockaddr(&addr, proxy_sa, &req->port) < 0) { tor_fragile_assert(); return -1; } tor_addr_to_str(req->address, &addr, sizeof(req->address), 0); return 0; } #endif /* defined(__FreeBSD__) */ memset(&pnl, 0, sizeof(pnl)); pnl.proto = IPPROTO_TCP; pnl.direction = PF_OUT; if (proxy_sa->sa_family == AF_INET) { struct sockaddr_in *sin = (struct sockaddr_in *)proxy_sa; pnl.af = AF_INET; pnl.saddr.v4.s_addr = tor_addr_to_ipv4n(&ENTRY_TO_CONN(conn)->addr); pnl.sport = htons(ENTRY_TO_CONN(conn)->port); pnl.daddr.v4.s_addr = sin->sin_addr.s_addr; pnl.dport = sin->sin_port; } else if (proxy_sa->sa_family == AF_INET6) { struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)proxy_sa; pnl.af = AF_INET6; memcpy(&pnl.saddr.v6, tor_addr_to_in6(&ENTRY_TO_CONN(conn)->addr), sizeof(struct in6_addr)); pnl.sport = htons(ENTRY_TO_CONN(conn)->port); memcpy(&pnl.daddr.v6, &sin6->sin6_addr, sizeof(struct in6_addr)); pnl.dport = sin6->sin6_port; } else { log_warn(LD_NET, "getsockname() gave an unexpected address family (%d)", (int)proxy_sa->sa_family); return -1; } pf = get_pf_socket(); if (pf<0) return -1; if (ioctl(pf, DIOCNATLOOK, &pnl) < 0) { log_warn(LD_NET, "ioctl(DIOCNATLOOK) failed: %s", strerror(errno)); return -1; } if (pnl.af == AF_INET) { tor_addr_from_ipv4n(&addr, pnl.rdaddr.v4.s_addr); } else if (pnl.af == AF_INET6) { tor_addr_from_in6(&addr, &pnl.rdaddr.v6); } else { tor_fragile_assert(); return -1; } tor_addr_to_str(req->address, &addr, sizeof(req->address), 1); req->port = ntohs(pnl.rdport); return 0; } #endif /* defined(TRANS_PF) */ /** Fetch the original destination address and port from a * system-specific interface and put them into a * socks_request_t as if they came from a socks request. * * Return -1 if an error prevents fetching the destination, * else return 0. */ static int connection_ap_get_original_destination(entry_connection_t *conn, socks_request_t *req) { #ifdef TRANS_NETFILTER return destination_from_socket(conn, req); #elif defined(TRANS_PF) const or_options_t *options = get_options(); if (options->TransProxyType_parsed == TPT_PF_DIVERT) return destination_from_socket(conn, req); if (options->TransProxyType_parsed == TPT_DEFAULT || options->TransProxyType_parsed == TPT_IPFW) return destination_from_pf(conn, req); (void)conn; (void)req; log_warn(LD_BUG, "Proxy destination determination mechanism %s unknown.", options->TransProxyType); return -1; #else (void)conn; (void)req; log_warn(LD_BUG, "Called connection_ap_get_original_destination, but no " "transparent proxy method was configured."); return -1; #endif /* defined(TRANS_NETFILTER) || ... */ } /** connection_edge_process_inbuf() found a conn in state * socks_wait. See if conn->inbuf has the right bytes to proceed with * the socks handshake. * * If the handshake is complete, send it to * connection_ap_handshake_rewrite_and_attach(). * * Return -1 if an unexpected error with conn occurs (and mark it for close), * else return 0. */ static int connection_ap_handshake_process_socks(entry_connection_t *conn) { socks_request_t *socks; int sockshere; const or_options_t *options = get_options(); int had_reply = 0; connection_t *base_conn = ENTRY_TO_CONN(conn); tor_assert(conn); tor_assert(base_conn->type == CONN_TYPE_AP); tor_assert(base_conn->state == AP_CONN_STATE_SOCKS_WAIT); tor_assert(conn->socks_request); socks = conn->socks_request; log_debug(LD_APP,"entered."); sockshere = fetch_from_buf_socks(base_conn->inbuf, socks, options->TestSocks, options->SafeSocks); if (socks->replylen) { had_reply = 1; connection_buf_add((const char*)socks->reply, socks->replylen, base_conn); socks->replylen = 0; if (sockshere == -1) { /* An invalid request just got a reply, no additional * one is necessary. */ socks->has_finished = 1; } } if (sockshere == 0) { log_debug(LD_APP,"socks handshake not all here yet."); return 0; } else if (sockshere == -1) { if (!had_reply) { log_warn(LD_APP,"Fetching socks handshake failed. Closing."); connection_ap_handshake_socks_reply(conn, NULL, 0, END_STREAM_REASON_SOCKSPROTOCOL); } connection_mark_unattached_ap(conn, END_STREAM_REASON_SOCKSPROTOCOL | END_STREAM_REASON_FLAG_ALREADY_SOCKS_REPLIED); return -1; } /* else socks handshake is done, continue processing */ if (SOCKS_COMMAND_IS_CONNECT(socks->command)) control_event_stream_status(conn, STREAM_EVENT_NEW, 0); else control_event_stream_status(conn, STREAM_EVENT_NEW_RESOLVE, 0); return connection_ap_rewrite_and_attach_if_allowed(conn, NULL, NULL); } /** connection_init_accepted_conn() found a new trans AP conn. * Get the original destination and send it to * connection_ap_handshake_rewrite_and_attach(). * * Return -1 if an unexpected error with conn (and it should be marked * for close), else return 0. */ int connection_ap_process_transparent(entry_connection_t *conn) { socks_request_t *socks; tor_assert(conn); tor_assert(conn->socks_request); socks = conn->socks_request; /* pretend that a socks handshake completed so we don't try to * send a socks reply down a transparent conn */ socks->command = SOCKS_COMMAND_CONNECT; socks->has_finished = 1; log_debug(LD_APP,"entered."); if (connection_ap_get_original_destination(conn, socks) < 0) { log_warn(LD_APP,"Fetching original destination failed. Closing."); connection_mark_unattached_ap(conn, END_STREAM_REASON_CANT_FETCH_ORIG_DEST); return -1; } /* we have the original destination */ control_event_stream_status(conn, STREAM_EVENT_NEW, 0); return connection_ap_rewrite_and_attach_if_allowed(conn, NULL, NULL); } /** connection_edge_process_inbuf() found a conn in state natd_wait. See if * conn-\>inbuf has the right bytes to proceed. See FreeBSD's libalias(3) and * ProxyEncodeTcpStream() in src/lib/libalias/alias_proxy.c for the encoding * form of the original destination. * * If the original destination is complete, send it to * connection_ap_handshake_rewrite_and_attach(). * * Return -1 if an unexpected error with conn (and it should be marked * for close), else return 0. */ static int connection_ap_process_natd(entry_connection_t *conn) { char tmp_buf[36], *tbuf, *daddr; size_t tlen = 30; int err, port_ok; socks_request_t *socks; tor_assert(conn); tor_assert(ENTRY_TO_CONN(conn)->state == AP_CONN_STATE_NATD_WAIT); tor_assert(conn->socks_request); socks = conn->socks_request; log_debug(LD_APP,"entered."); /* look for LF-terminated "[DEST ip_addr port]" * where ip_addr is a dotted-quad and port is in string form */ err = connection_buf_get_line(ENTRY_TO_CONN(conn), tmp_buf, &tlen); if (err == 0) return 0; if (err < 0) { log_warn(LD_APP,"NATD handshake failed (DEST too long). Closing"); connection_mark_unattached_ap(conn, END_STREAM_REASON_INVALID_NATD_DEST); return -1; } if (strcmpstart(tmp_buf, "[DEST ")) { log_warn(LD_APP,"NATD handshake was ill-formed; closing. The client " "said: %s", escaped(tmp_buf)); connection_mark_unattached_ap(conn, END_STREAM_REASON_INVALID_NATD_DEST); return -1; } daddr = tbuf = &tmp_buf[0] + 6; /* after end of "[DEST " */ if (!(tbuf = strchr(tbuf, ' '))) { log_warn(LD_APP,"NATD handshake was ill-formed; closing. The client " "said: %s", escaped(tmp_buf)); connection_mark_unattached_ap(conn, END_STREAM_REASON_INVALID_NATD_DEST); return -1; } *tbuf++ = '\0'; /* pretend that a socks handshake completed so we don't try to * send a socks reply down a natd conn */ strlcpy(socks->address, daddr, sizeof(socks->address)); socks->port = (uint16_t) tor_parse_long(tbuf, 10, 1, 65535, &port_ok, &daddr); if (!port_ok) { log_warn(LD_APP,"NATD handshake failed; port %s is ill-formed or out " "of range.", escaped(tbuf)); connection_mark_unattached_ap(conn, END_STREAM_REASON_INVALID_NATD_DEST); return -1; } socks->command = SOCKS_COMMAND_CONNECT; socks->has_finished = 1; control_event_stream_status(conn, STREAM_EVENT_NEW, 0); ENTRY_TO_CONN(conn)->state = AP_CONN_STATE_CIRCUIT_WAIT; return connection_ap_rewrite_and_attach_if_allowed(conn, NULL, NULL); } /** Called on an HTTP CONNECT entry connection when some bytes have arrived, * but we have not yet received a full HTTP CONNECT request. Try to parse an * HTTP CONNECT request from the connection's inbuf. On success, set up the * connection's socks_request field and try to attach the connection. On * failure, send an HTTP reply, and mark the connection. */ STATIC int connection_ap_process_http_connect(entry_connection_t *conn) { if (BUG(ENTRY_TO_CONN(conn)->state != AP_CONN_STATE_HTTP_CONNECT_WAIT)) return -1; char *headers = NULL, *body = NULL; char *command = NULL, *addrport = NULL; char *addr = NULL; size_t bodylen = 0; const char *errmsg = NULL; int rv = 0; const int http_status = fetch_from_buf_http(ENTRY_TO_CONN(conn)->inbuf, &headers, 8192, &body, &bodylen, 1024, 0); if (http_status < 0) { /* Bad http status */ errmsg = "HTTP/1.0 400 Bad Request\r\n\r\n"; goto err; } else if (http_status == 0) { /* no HTTP request yet. */ goto done; } const int cmd_status = parse_http_command(headers, &command, &addrport); if (cmd_status < 0) { errmsg = "HTTP/1.0 400 Bad Request\r\n\r\n"; goto err; } tor_assert(command); tor_assert(addrport); if (strcasecmp(command, "connect")) { errmsg = "HTTP/1.0 405 Method Not Allowed\r\n\r\n"; goto err; } tor_assert(conn->socks_request); socks_request_t *socks = conn->socks_request; uint16_t port; if (tor_addr_port_split(LOG_WARN, addrport, &addr, &port) < 0) { errmsg = "HTTP/1.0 400 Bad Request\r\n\r\n"; goto err; } if (strlen(addr) >= MAX_SOCKS_ADDR_LEN) { errmsg = "HTTP/1.0 414 Request-URI Too Long\r\n\r\n"; goto err; } /* Abuse the 'username' and 'password' fields here. They are already an * abuse. */ { char *authorization = http_get_header(headers, "Proxy-Authorization: "); if (authorization) { socks->username = authorization; // steal reference socks->usernamelen = strlen(authorization); } char *isolation = http_get_header(headers, "X-Tor-Stream-Isolation: "); if (isolation) { socks->password = isolation; // steal reference socks->passwordlen = strlen(isolation); } } socks->command = SOCKS_COMMAND_CONNECT; socks->listener_type = CONN_TYPE_AP_HTTP_CONNECT_LISTENER; strlcpy(socks->address, addr, sizeof(socks->address)); socks->port = port; control_event_stream_status(conn, STREAM_EVENT_NEW, 0); rv = connection_ap_rewrite_and_attach_if_allowed(conn, NULL, NULL); // XXXX send a "100 Continue" message? goto done; err: if (BUG(errmsg == NULL)) errmsg = "HTTP/1.0 400 Bad Request\r\n\r\n"; log_warn(LD_EDGE, "Saying %s", escaped(errmsg)); connection_buf_add(errmsg, strlen(errmsg), ENTRY_TO_CONN(conn)); connection_mark_unattached_ap(conn, END_STREAM_REASON_HTTPPROTOCOL| END_STREAM_REASON_FLAG_ALREADY_SOCKS_REPLIED); done: tor_free(headers); tor_free(body); tor_free(command); tor_free(addrport); tor_free(addr); return rv; } /** Iterate over the two bytes of stream_id until we get one that is not * already in use; return it. Return 0 if can't get a unique stream_id. */ streamid_t get_unique_stream_id_by_circ(origin_circuit_t *circ) { edge_connection_t *tmpconn; streamid_t test_stream_id; uint32_t attempts=0; again: test_stream_id = circ->next_stream_id++; if (++attempts > 1<<16) { /* Make sure we don't loop forever if all stream_id's are used. */ log_warn(LD_APP,"No unused stream IDs. Failing."); return 0; } if (test_stream_id == 0) goto again; for (tmpconn = circ->p_streams; tmpconn; tmpconn=tmpconn->next_stream) if (tmpconn->stream_id == test_stream_id) goto again; return test_stream_id; } /** Return true iff conn is linked to a circuit and configured to use * an exit that supports optimistic data. */ static int connection_ap_supports_optimistic_data(const entry_connection_t *conn) { const edge_connection_t *edge_conn = ENTRY_TO_EDGE_CONN(conn); /* We can only send optimistic data if we're connected to an open general circuit. */ if (edge_conn->on_circuit == NULL || edge_conn->on_circuit->state != CIRCUIT_STATE_OPEN || (edge_conn->on_circuit->purpose != CIRCUIT_PURPOSE_C_GENERAL && edge_conn->on_circuit->purpose != CIRCUIT_PURPOSE_C_HSDIR_GET && edge_conn->on_circuit->purpose != CIRCUIT_PURPOSE_S_HSDIR_POST && edge_conn->on_circuit->purpose != CIRCUIT_PURPOSE_C_REND_JOINED)) return 0; return conn->may_use_optimistic_data; } /** Return a bitmask of BEGIN_FLAG_* flags that we should transmit in the * RELAY_BEGIN cell for ap_conn. */ static uint32_t connection_ap_get_begincell_flags(entry_connection_t *ap_conn) { edge_connection_t *edge_conn = ENTRY_TO_EDGE_CONN(ap_conn); const node_t *exitnode = NULL; const crypt_path_t *cpath_layer = edge_conn->cpath_layer; uint32_t flags = 0; /* No flags for begindir */ if (ap_conn->use_begindir) return 0; /* No flags for hidden services. */ if (edge_conn->on_circuit->purpose != CIRCUIT_PURPOSE_C_GENERAL) return 0; /* If only IPv4 is supported, no flags */ if (ap_conn->entry_cfg.ipv4_traffic && !ap_conn->entry_cfg.ipv6_traffic) return 0; if (! cpath_layer || ! cpath_layer->extend_info) return 0; if (!ap_conn->entry_cfg.ipv4_traffic) flags |= BEGIN_FLAG_IPV4_NOT_OK; exitnode = node_get_by_id(cpath_layer->extend_info->identity_digest); if (ap_conn->entry_cfg.ipv6_traffic && exitnode) { tor_addr_t a; tor_addr_make_null(&a, AF_INET6); if (compare_tor_addr_to_node_policy(&a, ap_conn->socks_request->port, exitnode) != ADDR_POLICY_REJECTED) { /* Only say "IPv6 OK" if the exit node supports IPv6. Otherwise there's * no point. */ flags |= BEGIN_FLAG_IPV6_OK; } } if (flags == BEGIN_FLAG_IPV6_OK) { /* When IPv4 and IPv6 are both allowed, consider whether to say we * prefer IPv6. Otherwise there's no point in declaring a preference */ if (ap_conn->entry_cfg.prefer_ipv6) flags |= BEGIN_FLAG_IPV6_PREFERRED; } if (flags == BEGIN_FLAG_IPV4_NOT_OK) { log_warn(LD_EDGE, "I'm about to ask a node for a connection that I " "am telling it to fulfil with neither IPv4 nor IPv6. That's " "not going to work. Did you perhaps ask for an IPv6 address " "on an IPv4Only port, or vice versa?"); } return flags; } /** Write a relay begin cell, using destaddr and destport from ap_conn's * socks_request field, and send it down circ. * * If ap_conn is broken, mark it for close and return -1. Else return 0. */ MOCK_IMPL(int, connection_ap_handshake_send_begin,(entry_connection_t *ap_conn)) { char payload[CELL_PAYLOAD_SIZE]; int payload_len; int begin_type; const or_options_t *options = get_options(); origin_circuit_t *circ; edge_connection_t *edge_conn = ENTRY_TO_EDGE_CONN(ap_conn); connection_t *base_conn = TO_CONN(edge_conn); tor_assert(edge_conn->on_circuit); circ = TO_ORIGIN_CIRCUIT(edge_conn->on_circuit); tor_assert(base_conn->type == CONN_TYPE_AP); tor_assert(base_conn->state == AP_CONN_STATE_CIRCUIT_WAIT); tor_assert(ap_conn->socks_request); tor_assert(SOCKS_COMMAND_IS_CONNECT(ap_conn->socks_request->command)); edge_conn->stream_id = get_unique_stream_id_by_circ(circ); if (edge_conn->stream_id==0) { /* XXXX+ Instead of closing this stream, we should make it get * retried on another circuit. */ connection_mark_unattached_ap(ap_conn, END_STREAM_REASON_INTERNAL); /* Mark this circuit "unusable for new streams". */ mark_circuit_unusable_for_new_conns(circ); return -1; } /* Set up begin cell flags. */ edge_conn->begincell_flags = connection_ap_get_begincell_flags(ap_conn); tor_snprintf(payload,RELAY_PAYLOAD_SIZE, "%s:%d", (circ->base_.purpose == CIRCUIT_PURPOSE_C_GENERAL) ? ap_conn->socks_request->address : "", ap_conn->socks_request->port); payload_len = (int)strlen(payload)+1; if (payload_len <= RELAY_PAYLOAD_SIZE - 4 && edge_conn->begincell_flags) { set_uint32(payload + payload_len, htonl(edge_conn->begincell_flags)); payload_len += 4; } log_info(LD_APP, "Sending relay cell %d on circ %u to begin stream %d.", (int)ap_conn->use_begindir, (unsigned)circ->base_.n_circ_id, edge_conn->stream_id); begin_type = ap_conn->use_begindir ? RELAY_COMMAND_BEGIN_DIR : RELAY_COMMAND_BEGIN; /* Check that circuits are anonymised, based on their type. */ if (begin_type == RELAY_COMMAND_BEGIN) { /* This connection is a standard OR connection. * Make sure its path length is anonymous, or that we're in a * non-anonymous mode. */ assert_circ_anonymity_ok(circ, options); } else if (begin_type == RELAY_COMMAND_BEGIN_DIR) { /* This connection is a begindir directory connection. * Look at the linked directory connection to access the directory purpose. * If a BEGINDIR connection is ever not linked, that's a bug. */ if (BUG(!base_conn->linked)) { return -1; } connection_t *linked_dir_conn_base = base_conn->linked_conn; /* If the linked connection has been unlinked by other code, we can't send * a begin cell on it. */ if (!linked_dir_conn_base) { return -1; } /* Sensitive directory connections must have an anonymous path length. * Otherwise, directory connections are typically one-hop. * This matches the earlier check for directory connection path anonymity * in directory_initiate_request(). */ if (purpose_needs_anonymity(linked_dir_conn_base->purpose, TO_DIR_CONN(linked_dir_conn_base)->router_purpose, TO_DIR_CONN(linked_dir_conn_base)->requested_resource)) { assert_circ_anonymity_ok(circ, options); } } else { /* This code was written for the two connection types BEGIN and BEGIN_DIR */ tor_assert_unreached(); } if (connection_edge_send_command(edge_conn, begin_type, begin_type == RELAY_COMMAND_BEGIN ? payload : NULL, begin_type == RELAY_COMMAND_BEGIN ? payload_len : 0) < 0) return -1; /* circuit is closed, don't continue */ edge_conn->package_window = STREAMWINDOW_START; edge_conn->deliver_window = STREAMWINDOW_START; base_conn->state = AP_CONN_STATE_CONNECT_WAIT; log_info(LD_APP,"Address/port sent, ap socket "TOR_SOCKET_T_FORMAT ", n_circ_id %u", base_conn->s, (unsigned)circ->base_.n_circ_id); control_event_stream_status(ap_conn, STREAM_EVENT_SENT_CONNECT, 0); /* If there's queued-up data, send it now */ if ((connection_get_inbuf_len(base_conn) || ap_conn->sending_optimistic_data) && connection_ap_supports_optimistic_data(ap_conn)) { log_info(LD_APP, "Sending up to %ld + %ld bytes of queued-up data", (long)connection_get_inbuf_len(base_conn), ap_conn->sending_optimistic_data ? (long)buf_datalen(ap_conn->sending_optimistic_data) : 0); if (connection_edge_package_raw_inbuf(edge_conn, 1, NULL) < 0) { connection_mark_for_close(base_conn); } } return 0; } /** Write a relay resolve cell, using destaddr and destport from ap_conn's * socks_request field, and send it down circ. * * If ap_conn is broken, mark it for close and return -1. Else return 0. */ int connection_ap_handshake_send_resolve(entry_connection_t *ap_conn) { int payload_len, command; const char *string_addr; char inaddr_buf[REVERSE_LOOKUP_NAME_BUF_LEN]; origin_circuit_t *circ; edge_connection_t *edge_conn = ENTRY_TO_EDGE_CONN(ap_conn); connection_t *base_conn = TO_CONN(edge_conn); tor_assert(edge_conn->on_circuit); circ = TO_ORIGIN_CIRCUIT(edge_conn->on_circuit); tor_assert(base_conn->type == CONN_TYPE_AP); tor_assert(base_conn->state == AP_CONN_STATE_CIRCUIT_WAIT); tor_assert(ap_conn->socks_request); tor_assert(circ->base_.purpose == CIRCUIT_PURPOSE_C_GENERAL); command = ap_conn->socks_request->command; tor_assert(SOCKS_COMMAND_IS_RESOLVE(command)); edge_conn->stream_id = get_unique_stream_id_by_circ(circ); if (edge_conn->stream_id==0) { /* XXXX+ Instead of closing this stream, we should make it get * retried on another circuit. */ connection_mark_unattached_ap(ap_conn, END_STREAM_REASON_INTERNAL); /* Mark this circuit "unusable for new streams". */ mark_circuit_unusable_for_new_conns(circ); return -1; } if (command == SOCKS_COMMAND_RESOLVE) { string_addr = ap_conn->socks_request->address; payload_len = (int)strlen(string_addr)+1; } else { /* command == SOCKS_COMMAND_RESOLVE_PTR */ const char *a = ap_conn->socks_request->address; tor_addr_t addr; int r; /* We're doing a reverse lookup. The input could be an IP address, or * could be an .in-addr.arpa or .ip6.arpa address */ r = tor_addr_parse_PTR_name(&addr, a, AF_UNSPEC, 1); if (r <= 0) { log_warn(LD_APP, "Rejecting ill-formed reverse lookup of %s", safe_str_client(a)); connection_mark_unattached_ap(ap_conn, END_STREAM_REASON_INTERNAL); return -1; } r = tor_addr_to_PTR_name(inaddr_buf, sizeof(inaddr_buf), &addr); if (r < 0) { log_warn(LD_BUG, "Couldn't generate reverse lookup hostname of %s", safe_str_client(a)); connection_mark_unattached_ap(ap_conn, END_STREAM_REASON_INTERNAL); return -1; } string_addr = inaddr_buf; payload_len = (int)strlen(inaddr_buf)+1; tor_assert(payload_len <= (int)sizeof(inaddr_buf)); } log_debug(LD_APP, "Sending relay cell to begin stream %d.", edge_conn->stream_id); if (connection_edge_send_command(edge_conn, RELAY_COMMAND_RESOLVE, string_addr, payload_len) < 0) return -1; /* circuit is closed, don't continue */ if (!base_conn->address) { /* This might be unnecessary. XXXX */ base_conn->address = tor_addr_to_str_dup(&base_conn->addr); } base_conn->state = AP_CONN_STATE_RESOLVE_WAIT; log_info(LD_APP,"Address sent for resolve, ap socket "TOR_SOCKET_T_FORMAT ", n_circ_id %u", base_conn->s, (unsigned)circ->base_.n_circ_id); control_event_stream_status(ap_conn, STREAM_EVENT_SENT_RESOLVE, 0); return 0; } /** Make an AP connection_t linked to the connection_t partner. make a * new linked connection pair, and attach one side to the conn, connection_add * it, initialize it to circuit_wait, and call * connection_ap_handshake_attach_circuit(conn) on it. * * Return the newly created end of the linked connection pair, or -1 if error. */ entry_connection_t * connection_ap_make_link(connection_t *partner, char *address, uint16_t port, const char *digest, int session_group, int isolation_flags, int use_begindir, int want_onehop) { entry_connection_t *conn; connection_t *base_conn; log_info(LD_APP,"Making internal %s tunnel to %s:%d ...", want_onehop ? "direct" : "anonymized", safe_str_client(address), port); conn = entry_connection_new(CONN_TYPE_AP, tor_addr_family(&partner->addr)); base_conn = ENTRY_TO_CONN(conn); base_conn->linked = 1; /* so that we can add it safely below. */ /* populate conn->socks_request */ /* leave version at zero, so the socks_reply is empty */ conn->socks_request->socks_version = 0; conn->socks_request->has_finished = 0; /* waiting for 'connected' */ strlcpy(conn->socks_request->address, address, sizeof(conn->socks_request->address)); conn->socks_request->port = port; conn->socks_request->command = SOCKS_COMMAND_CONNECT; conn->want_onehop = want_onehop; conn->use_begindir = use_begindir; if (use_begindir) { conn->chosen_exit_name = tor_malloc(HEX_DIGEST_LEN+2); conn->chosen_exit_name[0] = '$'; tor_assert(digest); base16_encode(conn->chosen_exit_name+1,HEX_DIGEST_LEN+1, digest, DIGEST_LEN); } /* Populate isolation fields. */ conn->socks_request->listener_type = CONN_TYPE_DIR_LISTENER; conn->original_dest_address = tor_strdup(address); conn->entry_cfg.session_group = session_group; conn->entry_cfg.isolation_flags = isolation_flags; base_conn->address = tor_strdup("(Tor_internal)"); tor_addr_make_unspec(&base_conn->addr); base_conn->port = 0; connection_link_connections(partner, base_conn); if (connection_add(base_conn) < 0) { /* no space, forget it */ connection_free(base_conn); return NULL; } base_conn->state = AP_CONN_STATE_CIRCUIT_WAIT; control_event_stream_status(conn, STREAM_EVENT_NEW, 0); /* attaching to a dirty circuit is fine */ connection_ap_mark_as_pending_circuit(conn); log_info(LD_APP,"... application connection created and linked."); return conn; } /** Notify any interested controller connections about a new hostname resolve * or resolve error. Takes the same arguments as does * connection_ap_handshake_socks_resolved(). */ static void tell_controller_about_resolved_result(entry_connection_t *conn, int answer_type, size_t answer_len, const char *answer, int ttl, time_t expires) { expires = time(NULL) + ttl; if (answer_type == RESOLVED_TYPE_IPV4 && answer_len >= 4) { char *cp = tor_dup_ip(ntohl(get_uint32(answer))); control_event_address_mapped(conn->socks_request->address, cp, expires, NULL, 0); tor_free(cp); } else if (answer_type == RESOLVED_TYPE_HOSTNAME && answer_len < 256) { char *cp = tor_strndup(answer, answer_len); control_event_address_mapped(conn->socks_request->address, cp, expires, NULL, 0); tor_free(cp); } else { control_event_address_mapped(conn->socks_request->address, "", time(NULL)+ttl, "error=yes", 0); } } /** * As connection_ap_handshake_socks_resolved, but take a tor_addr_t to send * as the answer. */ void connection_ap_handshake_socks_resolved_addr(entry_connection_t *conn, const tor_addr_t *answer, int ttl, time_t expires) { if (tor_addr_family(answer) == AF_INET) { uint32_t a = tor_addr_to_ipv4n(answer); /* network order */ connection_ap_handshake_socks_resolved(conn,RESOLVED_TYPE_IPV4,4, (uint8_t*)&a, ttl, expires); } else if (tor_addr_family(answer) == AF_INET6) { const uint8_t *a = tor_addr_to_in6_addr8(answer); connection_ap_handshake_socks_resolved(conn,RESOLVED_TYPE_IPV6,16, a, ttl, expires); } else { log_warn(LD_BUG, "Got called with address of unexpected family %d", tor_addr_family(answer)); connection_ap_handshake_socks_resolved(conn, RESOLVED_TYPE_ERROR,0,NULL,-1,-1); } } /** Send an answer to an AP connection that has requested a DNS lookup via * SOCKS. The type should be one of RESOLVED_TYPE_(IPV4|IPV6|HOSTNAME) or -1 * for unreachable; the answer should be in the format specified in the socks * extensions document. ttl is the ttl for the answer, or -1 on * certain errors or for values that didn't come via DNS. expires is * a time when the answer expires, or -1 or TIME_MAX if there's a good TTL. **/ /* XXXX the use of the ttl and expires fields is nutty. Let's make this * interface and those that use it less ugly. */ MOCK_IMPL(void, connection_ap_handshake_socks_resolved,(entry_connection_t *conn, int answer_type, size_t answer_len, const uint8_t *answer, int ttl, time_t expires)) { char buf[384]; size_t replylen; if (ttl >= 0) { if (answer_type == RESOLVED_TYPE_IPV4 && answer_len == 4) { tor_addr_t a; tor_addr_from_ipv4n(&a, get_uint32(answer)); if (! tor_addr_is_null(&a)) { client_dns_set_addressmap(conn, conn->socks_request->address, &a, conn->chosen_exit_name, ttl); } } else if (answer_type == RESOLVED_TYPE_IPV6 && answer_len == 16) { tor_addr_t a; tor_addr_from_ipv6_bytes(&a, (char*)answer); if (! tor_addr_is_null(&a)) { client_dns_set_addressmap(conn, conn->socks_request->address, &a, conn->chosen_exit_name, ttl); } } else if (answer_type == RESOLVED_TYPE_HOSTNAME && answer_len < 256) { char *cp = tor_strndup((char*)answer, answer_len); client_dns_set_reverse_addressmap(conn, conn->socks_request->address, cp, conn->chosen_exit_name, ttl); tor_free(cp); } } if (ENTRY_TO_EDGE_CONN(conn)->is_dns_request) { if (conn->dns_server_request) { /* We had a request on our DNS port: answer it. */ dnsserv_resolved(conn, answer_type, answer_len, (char*)answer, ttl); conn->socks_request->has_finished = 1; return; } else { /* This must be a request from the controller. Since answers to those * requests are not cached, they do not generate an ADDRMAP event on * their own. */ tell_controller_about_resolved_result(conn, answer_type, answer_len, (char*)answer, ttl, expires); conn->socks_request->has_finished = 1; return; } /* We shouldn't need to free conn here; it gets marked by the caller. */ } if (conn->socks_request->socks_version == 4) { buf[0] = 0x00; /* version */ if (answer_type == RESOLVED_TYPE_IPV4 && answer_len == 4) { buf[1] = SOCKS4_GRANTED; set_uint16(buf+2, 0); memcpy(buf+4, answer, 4); /* address */ replylen = SOCKS4_NETWORK_LEN; } else { /* "error" */ buf[1] = SOCKS4_REJECT; memset(buf+2, 0, 6); replylen = SOCKS4_NETWORK_LEN; } } else if (conn->socks_request->socks_version == 5) { /* SOCKS5 */ buf[0] = 0x05; /* version */ if (answer_type == RESOLVED_TYPE_IPV4 && answer_len == 4) { buf[1] = SOCKS5_SUCCEEDED; buf[2] = 0; /* reserved */ buf[3] = 0x01; /* IPv4 address type */ memcpy(buf+4, answer, 4); /* address */ set_uint16(buf+8, 0); /* port == 0. */ replylen = 10; } else if (answer_type == RESOLVED_TYPE_IPV6 && answer_len == 16) { buf[1] = SOCKS5_SUCCEEDED; buf[2] = 0; /* reserved */ buf[3] = 0x04; /* IPv6 address type */ memcpy(buf+4, answer, 16); /* address */ set_uint16(buf+20, 0); /* port == 0. */ replylen = 22; } else if (answer_type == RESOLVED_TYPE_HOSTNAME && answer_len < 256) { buf[1] = SOCKS5_SUCCEEDED; buf[2] = 0; /* reserved */ buf[3] = 0x03; /* Domainname address type */ buf[4] = (char)answer_len; memcpy(buf+5, answer, answer_len); /* address */ set_uint16(buf+5+answer_len, 0); /* port == 0. */ replylen = 5+answer_len+2; } else { buf[1] = SOCKS5_HOST_UNREACHABLE; memset(buf+2, 0, 8); replylen = 10; } } else { /* no socks version info; don't send anything back */ return; } connection_ap_handshake_socks_reply(conn, buf, replylen, (answer_type == RESOLVED_TYPE_IPV4 || answer_type == RESOLVED_TYPE_IPV6 || answer_type == RESOLVED_TYPE_HOSTNAME) ? 0 : END_STREAM_REASON_RESOLVEFAILED); } /** Send a socks reply to stream conn, using the appropriate * socks version, etc, and mark conn as completed with SOCKS * handshaking. * * If reply is defined, then write replylen bytes of it to conn * and return, else reply based on endreason (one of * END_STREAM_REASON_*). If reply is undefined, endreason can't * be 0 or REASON_DONE. Send endreason to the controller, if appropriate. */ void connection_ap_handshake_socks_reply(entry_connection_t *conn, char *reply, size_t replylen, int endreason) { char buf[256]; socks5_reply_status_t status = stream_end_reason_to_socks5_response(endreason); tor_assert(conn->socks_request); /* make sure it's an AP stream */ if (!SOCKS_COMMAND_IS_RESOLVE(conn->socks_request->command)) { control_event_stream_status(conn, status==SOCKS5_SUCCEEDED ? STREAM_EVENT_SUCCEEDED : STREAM_EVENT_FAILED, endreason); } /* Flag this stream's circuit as having completed a stream successfully * (for path bias) */ if (status == SOCKS5_SUCCEEDED || endreason == END_STREAM_REASON_RESOLVEFAILED || endreason == END_STREAM_REASON_CONNECTREFUSED || endreason == END_STREAM_REASON_CONNRESET || endreason == END_STREAM_REASON_NOROUTE || endreason == END_STREAM_REASON_RESOURCELIMIT) { if (!conn->edge_.on_circuit || !CIRCUIT_IS_ORIGIN(conn->edge_.on_circuit)) { if (endreason != END_STREAM_REASON_RESOLVEFAILED) { log_info(LD_BUG, "No origin circuit for successful SOCKS stream "U64_FORMAT ". Reason: %d", U64_PRINTF_ARG(ENTRY_TO_CONN(conn)->global_identifier), endreason); } /* * Else DNS remaps and failed hidden service lookups can send us * here with END_STREAM_REASON_RESOLVEFAILED; ignore it * * Perhaps we could make the test more precise; we can tell hidden * services by conn->edge_.renddata != NULL; anything analogous for * the DNS remap case? */ } else { // XXX: Hrmm. It looks like optimistic data can't go through this // codepath, but someone should probably test it and make sure. // We don't want to mark optimistically opened streams as successful. pathbias_mark_use_success(TO_ORIGIN_CIRCUIT(conn->edge_.on_circuit)); } } if (conn->socks_request->has_finished) { log_warn(LD_BUG, "(Harmless.) duplicate calls to " "connection_ap_handshake_socks_reply."); return; } if (replylen) { /* we already have a reply in mind */ connection_buf_add(reply, replylen, ENTRY_TO_CONN(conn)); conn->socks_request->has_finished = 1; return; } if (conn->socks_request->listener_type == CONN_TYPE_AP_HTTP_CONNECT_LISTENER) { const char *response = end_reason_to_http_connect_response_line(endreason); if (!response) { response = "HTTP/1.0 400 Bad Request\r\n\r\n"; } connection_buf_add(response, strlen(response), ENTRY_TO_CONN(conn)); } else if (conn->socks_request->socks_version == 4) { memset(buf,0,SOCKS4_NETWORK_LEN); buf[1] = (status==SOCKS5_SUCCEEDED ? SOCKS4_GRANTED : SOCKS4_REJECT); /* leave version, destport, destip zero */ connection_buf_add(buf, SOCKS4_NETWORK_LEN, ENTRY_TO_CONN(conn)); } else if (conn->socks_request->socks_version == 5) { size_t buf_len; memset(buf,0,sizeof(buf)); if (tor_addr_family(&conn->edge_.base_.addr) == AF_INET) { buf[0] = 5; /* version 5 */ buf[1] = (char)status; buf[2] = 0; buf[3] = 1; /* ipv4 addr */ /* 4 bytes for the header, 2 bytes for the port, 4 for the address. */ buf_len = 10; } else { /* AF_INET6. */ buf[0] = 5; /* version 5 */ buf[1] = (char)status; buf[2] = 0; buf[3] = 4; /* ipv6 addr */ /* 4 bytes for the header, 2 bytes for the port, 16 for the address. */ buf_len = 22; } connection_buf_add(buf,buf_len,ENTRY_TO_CONN(conn)); } /* If socks_version isn't 4 or 5, don't send anything. * This can happen in the case of AP bridges. */ conn->socks_request->has_finished = 1; return; } /** Read a RELAY_BEGIN or RELAY_BEGIN_DIR cell from cell, decode it, and * place the result in bcell. On success return 0; on failure return * <0 and set *end_reason_out to the end reason we should send back to * the client. * * Return -1 in the case where we want to send a RELAY_END cell, and < -1 when * we don't. **/ STATIC int begin_cell_parse(const cell_t *cell, begin_cell_t *bcell, uint8_t *end_reason_out) { relay_header_t rh; const uint8_t *body, *nul; memset(bcell, 0, sizeof(*bcell)); *end_reason_out = END_STREAM_REASON_MISC; relay_header_unpack(&rh, cell->payload); if (rh.length > RELAY_PAYLOAD_SIZE) { return -2; /*XXXX why not TORPROTOCOL? */ } bcell->stream_id = rh.stream_id; if (rh.command == RELAY_COMMAND_BEGIN_DIR) { bcell->is_begindir = 1; return 0; } else if (rh.command != RELAY_COMMAND_BEGIN) { log_warn(LD_BUG, "Got an unexpected command %d", (int)rh.command); *end_reason_out = END_STREAM_REASON_INTERNAL; return -1; } body = cell->payload + RELAY_HEADER_SIZE; nul = memchr(body, 0, rh.length); if (! nul) { log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL, "Relay begin cell has no \\0. Closing."); *end_reason_out = END_STREAM_REASON_TORPROTOCOL; return -1; } if (tor_addr_port_split(LOG_PROTOCOL_WARN, (char*)(body), &bcell->address,&bcell->port)<0) { log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL, "Unable to parse addr:port in relay begin cell. Closing."); *end_reason_out = END_STREAM_REASON_TORPROTOCOL; return -1; } if (bcell->port == 0) { log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL, "Missing port in relay begin cell. Closing."); tor_free(bcell->address); *end_reason_out = END_STREAM_REASON_TORPROTOCOL; return -1; } if (body + rh.length >= nul + 4) bcell->flags = ntohl(get_uint32(nul+1)); return 0; } /** For the given circ and the edge connection conn, setup the * connection, attach it to the circ and connect it. Return 0 on success * or END_CIRC_AT_ORIGIN if we can't find the requested hidden service port * where the caller should close the circuit. */ static int handle_hs_exit_conn(circuit_t *circ, edge_connection_t *conn) { int ret; origin_circuit_t *origin_circ; assert_circuit_ok(circ); tor_assert(circ->purpose == CIRCUIT_PURPOSE_S_REND_JOINED); tor_assert(conn); log_debug(LD_REND, "Connecting the hidden service rendezvous circuit " "to the service destination."); origin_circ = TO_ORIGIN_CIRCUIT(circ); conn->base_.address = tor_strdup("(rendezvous)"); conn->base_.state = EXIT_CONN_STATE_CONNECTING; /* The circuit either has an hs identifier for v3+ or a rend_data for legacy * service. */ if (origin_circ->rend_data) { conn->rend_data = rend_data_dup(origin_circ->rend_data); tor_assert(connection_edge_is_rendezvous_stream(conn)); ret = rend_service_set_connection_addr_port(conn, origin_circ); } else if (origin_circ->hs_ident) { /* Setup the identifier to be the one for the circuit service. */ conn->hs_ident = hs_ident_edge_conn_new(&origin_circ->hs_ident->identity_pk); tor_assert(connection_edge_is_rendezvous_stream(conn)); ret = hs_service_set_conn_addr_port(origin_circ, conn); } else { /* We should never get here if the circuit's purpose is rendezvous. */ tor_assert_nonfatal_unreached(); return -1; } if (ret < 0) { log_info(LD_REND, "Didn't find rendezvous service (addr%s, port %d)", fmt_addr(&TO_CONN(conn)->addr), TO_CONN(conn)->port); /* Send back reason DONE because we want to make hidden service port * scanning harder thus instead of returning that the exit policy * didn't match, which makes it obvious that the port is closed, * return DONE and kill the circuit. That way, a user (malicious or * not) needs one circuit per bad port unless it matches the policy of * the hidden service. */ relay_send_end_cell_from_edge(conn->stream_id, circ, END_STREAM_REASON_DONE, origin_circ->cpath->prev); connection_free_(TO_CONN(conn)); /* Drop the circuit here since it might be someone deliberately * scanning the hidden service ports. Note that this mitigates port * scanning by adding more work on the attacker side to successfully * scan but does not fully solve it. */ if (ret < -1) { return END_CIRC_AT_ORIGIN; } else { return 0; } } /* Link the circuit and the connection crypt path. */ conn->cpath_layer = origin_circ->cpath->prev; /* Add it into the linked list of p_streams on this circuit */ conn->next_stream = origin_circ->p_streams; origin_circ->p_streams = conn; conn->on_circuit = circ; assert_circuit_ok(circ); hs_inc_rdv_stream_counter(origin_circ); /* Connect tor to the hidden service destination. */ connection_exit_connect(conn); /* For path bias: This circuit was used successfully */ pathbias_mark_use_success(origin_circ); return 0; } /** A relay 'begin' or 'begin_dir' cell has arrived, and either we are * an exit hop for the circuit, or we are the origin and it is a * rendezvous begin. * * Launch a new exit connection and initialize things appropriately. * * If it's a rendezvous stream, call connection_exit_connect() on * it. * * For general streams, call dns_resolve() on it first, and only call * connection_exit_connect() if the dns answer is already known. * * Note that we don't call connection_add() on the new stream! We wait * for connection_exit_connect() to do that. * * Return -(some circuit end reason) if we want to tear down circ. * Else return 0. */ int connection_exit_begin_conn(cell_t *cell, circuit_t *circ) { edge_connection_t *n_stream; relay_header_t rh; char *address = NULL; uint16_t port = 0; or_circuit_t *or_circ = NULL; origin_circuit_t *origin_circ = NULL; crypt_path_t *layer_hint = NULL; const or_options_t *options = get_options(); begin_cell_t bcell; int rv; uint8_t end_reason=0; assert_circuit_ok(circ); if (!CIRCUIT_IS_ORIGIN(circ)) { or_circ = TO_OR_CIRCUIT(circ); } else { tor_assert(circ->purpose == CIRCUIT_PURPOSE_S_REND_JOINED); origin_circ = TO_ORIGIN_CIRCUIT(circ); layer_hint = origin_circ->cpath->prev; } relay_header_unpack(&rh, cell->payload); if (rh.length > RELAY_PAYLOAD_SIZE) return -END_CIRC_REASON_TORPROTOCOL; if (!server_mode(options) && circ->purpose != CIRCUIT_PURPOSE_S_REND_JOINED) { log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL, "Relay begin cell at non-server. Closing."); relay_send_end_cell_from_edge(rh.stream_id, circ, END_STREAM_REASON_EXITPOLICY, NULL); return 0; } rv = begin_cell_parse(cell, &bcell, &end_reason); if (rv < -1) { return -END_CIRC_REASON_TORPROTOCOL; } else if (rv == -1) { tor_free(bcell.address); relay_send_end_cell_from_edge(rh.stream_id, circ, end_reason, layer_hint); return 0; } if (! bcell.is_begindir) { /* Steal reference */ address = bcell.address; port = bcell.port; if (or_circ && or_circ->p_chan) { const int client_chan = channel_is_client(or_circ->p_chan); if ((client_chan || (!connection_or_digest_is_known_relay( or_circ->p_chan->identity_digest) && should_refuse_unknown_exits(options)))) { /* Don't let clients use us as a single-hop proxy. It attracts * attackers and users who'd be better off with, well, single-hop * proxies. */ log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL, "Attempt by %s to open a stream %s. Closing.", safe_str(channel_get_canonical_remote_descr(or_circ->p_chan)), client_chan ? "on first hop of circuit" : "from unknown relay"); relay_send_end_cell_from_edge(rh.stream_id, circ, client_chan ? END_STREAM_REASON_TORPROTOCOL : END_STREAM_REASON_MISC, NULL); tor_free(address); return 0; } } } else if (rh.command == RELAY_COMMAND_BEGIN_DIR) { if (!directory_permits_begindir_requests(options) || circ->purpose != CIRCUIT_PURPOSE_OR) { relay_send_end_cell_from_edge(rh.stream_id, circ, END_STREAM_REASON_NOTDIRECTORY, layer_hint); return 0; } /* Make sure to get the 'real' address of the previous hop: the * caller might want to know whether the remote IP address has changed, * and we might already have corrected base_.addr[ess] for the relay's * canonical IP address. */ if (or_circ && or_circ->p_chan) address = tor_strdup(channel_get_actual_remote_address(or_circ->p_chan)); else address = tor_strdup("127.0.0.1"); port = 1; /* XXXX This value is never actually used anywhere, and there * isn't "really" a connection here. But we * need to set it to something nonzero. */ } else { log_warn(LD_BUG, "Got an unexpected command %d", (int)rh.command); relay_send_end_cell_from_edge(rh.stream_id, circ, END_STREAM_REASON_INTERNAL, layer_hint); return 0; } if (! options->IPv6Exit) { /* I don't care if you prefer IPv6; I can't give you any. */ bcell.flags &= ~BEGIN_FLAG_IPV6_PREFERRED; /* If you don't want IPv4, I can't help. */ if (bcell.flags & BEGIN_FLAG_IPV4_NOT_OK) { tor_free(address); relay_send_end_cell_from_edge(rh.stream_id, circ, END_STREAM_REASON_EXITPOLICY, layer_hint); return 0; } } log_debug(LD_EXIT,"Creating new exit connection."); /* The 'AF_INET' here is temporary; we might need to change it later in * connection_exit_connect(). */ n_stream = edge_connection_new(CONN_TYPE_EXIT, AF_INET); /* Remember the tunneled request ID in the new edge connection, so that * we can measure download times. */ n_stream->dirreq_id = circ->dirreq_id; n_stream->base_.purpose = EXIT_PURPOSE_CONNECT; n_stream->begincell_flags = bcell.flags; n_stream->stream_id = rh.stream_id; n_stream->base_.port = port; /* leave n_stream->s at -1, because it's not yet valid */ n_stream->package_window = STREAMWINDOW_START; n_stream->deliver_window = STREAMWINDOW_START; if (circ->purpose == CIRCUIT_PURPOSE_S_REND_JOINED) { int ret; tor_free(address); /* We handle this circuit and stream in this function for all supported * hidden service version. */ ret = handle_hs_exit_conn(circ, n_stream); if (ret == 0) { /* This was a valid cell. Count it as delivered + overhead. */ circuit_read_valid_data(origin_circ, rh.length); } return ret; } tor_strlower(address); n_stream->base_.address = address; n_stream->base_.state = EXIT_CONN_STATE_RESOLVEFAILED; /* default to failed, change in dns_resolve if it turns out not to fail */ /* If we're hibernating or shutting down, we refuse to open new streams. */ if (we_are_hibernating()) { relay_send_end_cell_from_edge(rh.stream_id, circ, END_STREAM_REASON_HIBERNATING, NULL); connection_free_(TO_CONN(n_stream)); return 0; } n_stream->on_circuit = circ; if (rh.command == RELAY_COMMAND_BEGIN_DIR) { tor_addr_t tmp_addr; tor_assert(or_circ); if (or_circ->p_chan && channel_get_addr_if_possible(or_circ->p_chan, &tmp_addr)) { tor_addr_copy(&n_stream->base_.addr, &tmp_addr); } return connection_exit_connect_dir(n_stream); } log_debug(LD_EXIT,"about to start the dns_resolve()."); /* send it off to the gethostbyname farm */ switch (dns_resolve(n_stream)) { case 1: /* resolve worked; now n_stream is attached to circ. */ assert_circuit_ok(circ); log_debug(LD_EXIT,"about to call connection_exit_connect()."); connection_exit_connect(n_stream); return 0; case -1: /* resolve failed */ relay_send_end_cell_from_edge(rh.stream_id, circ, END_STREAM_REASON_RESOLVEFAILED, NULL); /* n_stream got freed. don't touch it. */ break; case 0: /* resolve added to pending list */ assert_circuit_ok(circ); break; } return 0; } /** * Called when we receive a RELAY_COMMAND_RESOLVE cell 'cell' along the * circuit circ; * begin resolving the hostname, and (eventually) reply with a RESOLVED cell. */ int connection_exit_begin_resolve(cell_t *cell, or_circuit_t *circ) { edge_connection_t *dummy_conn; relay_header_t rh; assert_circuit_ok(TO_CIRCUIT(circ)); relay_header_unpack(&rh, cell->payload); if (rh.length > RELAY_PAYLOAD_SIZE) return -1; /* This 'dummy_conn' only exists to remember the stream ID * associated with the resolve request; and to make the * implementation of dns.c more uniform. (We really only need to * remember the circuit, the stream ID, and the hostname to be * resolved; but if we didn't store them in a connection like this, * the housekeeping in dns.c would get way more complicated.) */ dummy_conn = edge_connection_new(CONN_TYPE_EXIT, AF_INET); dummy_conn->stream_id = rh.stream_id; dummy_conn->base_.address = tor_strndup( (char*)cell->payload+RELAY_HEADER_SIZE, rh.length); dummy_conn->base_.port = 0; dummy_conn->base_.state = EXIT_CONN_STATE_RESOLVEFAILED; dummy_conn->base_.purpose = EXIT_PURPOSE_RESOLVE; dummy_conn->on_circuit = TO_CIRCUIT(circ); /* send it off to the gethostbyname farm */ switch (dns_resolve(dummy_conn)) { case -1: /* Impossible to resolve; a resolved cell was sent. */ /* Connection freed; don't touch it. */ return 0; case 1: /* The result was cached; a resolved cell was sent. */ if (!dummy_conn->base_.marked_for_close) connection_free_(TO_CONN(dummy_conn)); return 0; case 0: /* resolve added to pending list */ assert_circuit_ok(TO_CIRCUIT(circ)); break; } return 0; } /** Helper: Return true and set *why_rejected to an optional clarifying * message message iff we do not allow connections to addr:port. */ static int my_exit_policy_rejects(const tor_addr_t *addr, uint16_t port, const char **why_rejected) { if (router_compare_to_my_exit_policy(addr, port)) { *why_rejected = ""; return 1; } else if (tor_addr_family(addr) == AF_INET6 && !get_options()->IPv6Exit) { *why_rejected = " (IPv6 address without IPv6Exit configured)"; return 1; } return 0; } /** Connect to conn's specified addr and port. If it worked, conn * has now been added to the connection_array. * * Send back a connected cell. Include the resolved IP of the destination * address, but only if it's a general exit stream. (Rendezvous * streams must not reveal what IP they connected to.) */ void connection_exit_connect(edge_connection_t *edge_conn) { const tor_addr_t *addr; uint16_t port; connection_t *conn = TO_CONN(edge_conn); int socket_error = 0, result; const char *why_failed_exit_policy = NULL; /* Apply exit policy to non-rendezvous connections. */ if (! connection_edge_is_rendezvous_stream(edge_conn) && my_exit_policy_rejects(&edge_conn->base_.addr, edge_conn->base_.port, &why_failed_exit_policy)) { if (BUG(!why_failed_exit_policy)) why_failed_exit_policy = ""; log_info(LD_EXIT,"%s:%d failed exit policy%s. Closing.", escaped_safe_str_client(conn->address), conn->port, why_failed_exit_policy); connection_edge_end(edge_conn, END_STREAM_REASON_EXITPOLICY); circuit_detach_stream(circuit_get_by_edge_conn(edge_conn), edge_conn); connection_free(conn); return; } #ifdef HAVE_SYS_UN_H if (conn->socket_family != AF_UNIX) { #else { #endif /* defined(HAVE_SYS_UN_H) */ addr = &conn->addr; port = conn->port; if (tor_addr_family(addr) == AF_INET6) conn->socket_family = AF_INET6; log_debug(LD_EXIT, "about to try connecting"); result = connection_connect(conn, conn->address, addr, port, &socket_error); #ifdef HAVE_SYS_UN_H } else { /* * In the AF_UNIX case, we expect to have already had conn->port = 1, * tor_addr_make_unspec(conn->addr) (cf. the way we mark in the incoming * case in connection_handle_listener_read()), and conn->address should * have the socket path to connect to. */ tor_assert(conn->address && strlen(conn->address) > 0); log_debug(LD_EXIT, "about to try connecting"); result = connection_connect_unix(conn, conn->address, &socket_error); #endif /* defined(HAVE_SYS_UN_H) */ } switch (result) { case -1: { int reason = errno_to_stream_end_reason(socket_error); connection_edge_end(edge_conn, reason); circuit_detach_stream(circuit_get_by_edge_conn(edge_conn), edge_conn); connection_free(conn); return; } case 0: conn->state = EXIT_CONN_STATE_CONNECTING; connection_watch_events(conn, READ_EVENT | WRITE_EVENT); /* writable indicates finish; * readable/error indicates broken link in windows-land. */ return; /* case 1: fall through */ } conn->state = EXIT_CONN_STATE_OPEN; if (connection_get_outbuf_len(conn)) { /* in case there are any queued data cells, from e.g. optimistic data */ connection_watch_events(conn, READ_EVENT|WRITE_EVENT); } else { connection_watch_events(conn, READ_EVENT); } /* also, deliver a 'connected' cell back through the circuit. */ if (connection_edge_is_rendezvous_stream(edge_conn)) { /* don't send an address back! */ connection_edge_send_command(edge_conn, RELAY_COMMAND_CONNECTED, NULL, 0); } else { /* normal stream */ uint8_t connected_payload[MAX_CONNECTED_CELL_PAYLOAD_LEN]; int connected_payload_len = connected_cell_format_payload(connected_payload, &conn->addr, edge_conn->address_ttl); if (connected_payload_len < 0) { connection_edge_end(edge_conn, END_STREAM_REASON_INTERNAL); circuit_detach_stream(circuit_get_by_edge_conn(edge_conn), edge_conn); connection_free(conn); return; } connection_edge_send_command(edge_conn, RELAY_COMMAND_CONNECTED, (char*)connected_payload, connected_payload_len); } } /** Given an exit conn that should attach to us as a directory server, open a * bridge connection with a linked connection pair, create a new directory * conn, and join them together. Return 0 on success (or if there was an * error we could send back an end cell for). Return -(some circuit end * reason) if the circuit needs to be torn down. Either connects * exitconn, frees it, or marks it, as appropriate. */ static int connection_exit_connect_dir(edge_connection_t *exitconn) { dir_connection_t *dirconn = NULL; or_circuit_t *circ = TO_OR_CIRCUIT(exitconn->on_circuit); log_info(LD_EXIT, "Opening local connection for anonymized directory exit"); exitconn->base_.state = EXIT_CONN_STATE_OPEN; dirconn = dir_connection_new(tor_addr_family(&exitconn->base_.addr)); tor_addr_copy(&dirconn->base_.addr, &exitconn->base_.addr); dirconn->base_.port = 0; dirconn->base_.address = tor_strdup(exitconn->base_.address); dirconn->base_.type = CONN_TYPE_DIR; dirconn->base_.purpose = DIR_PURPOSE_SERVER; dirconn->base_.state = DIR_CONN_STATE_SERVER_COMMAND_WAIT; /* Note that the new dir conn belongs to the same tunneled request as * the edge conn, so that we can measure download times. */ dirconn->dirreq_id = exitconn->dirreq_id; connection_link_connections(TO_CONN(dirconn), TO_CONN(exitconn)); if (connection_add(TO_CONN(exitconn))<0) { connection_edge_end(exitconn, END_STREAM_REASON_RESOURCELIMIT); connection_free_(TO_CONN(exitconn)); connection_free_(TO_CONN(dirconn)); return 0; } /* link exitconn to circ, now that we know we can use it. */ exitconn->next_stream = circ->n_streams; circ->n_streams = exitconn; if (connection_add(TO_CONN(dirconn))<0) { connection_edge_end(exitconn, END_STREAM_REASON_RESOURCELIMIT); connection_close_immediate(TO_CONN(exitconn)); connection_mark_for_close(TO_CONN(exitconn)); connection_free_(TO_CONN(dirconn)); return 0; } connection_start_reading(TO_CONN(dirconn)); connection_start_reading(TO_CONN(exitconn)); if (connection_edge_send_command(exitconn, RELAY_COMMAND_CONNECTED, NULL, 0) < 0) { connection_mark_for_close(TO_CONN(exitconn)); connection_mark_for_close(TO_CONN(dirconn)); return 0; } return 0; } /** Return 1 if conn is a rendezvous stream, or 0 if * it is a general stream. */ int connection_edge_is_rendezvous_stream(const edge_connection_t *conn) { tor_assert(conn); /* It should not be possible to set both of these structs */ tor_assert_nonfatal(!(conn->rend_data && conn->hs_ident)); if (conn->rend_data || conn->hs_ident) { return 1; } return 0; } /** Return 1 if router exit_node is likely to allow stream conn * to exit from it, or 0 if it probably will not allow it. * (We might be uncertain if conn's destination address has not yet been * resolved.) */ int connection_ap_can_use_exit(const entry_connection_t *conn, const node_t *exit_node) { const or_options_t *options = get_options(); tor_assert(conn); tor_assert(conn->socks_request); tor_assert(exit_node); /* If a particular exit node has been requested for the new connection, * make sure the exit node of the existing circuit matches exactly. */ if (conn->chosen_exit_name) { const node_t *chosen_exit = node_get_by_nickname(conn->chosen_exit_name, 0); if (!chosen_exit || tor_memneq(chosen_exit->identity, exit_node->identity, DIGEST_LEN)) { /* doesn't match */ // log_debug(LD_APP,"Requested node '%s', considering node '%s'. No.", // conn->chosen_exit_name, exit->nickname); return 0; } } if (conn->use_begindir) { /* Internal directory fetches do not count as exiting. */ return 1; } if (conn->socks_request->command == SOCKS_COMMAND_CONNECT) { tor_addr_t addr, *addrp = NULL; addr_policy_result_t r; if (0 == tor_addr_parse(&addr, conn->socks_request->address)) { addrp = &addr; } else if (!conn->entry_cfg.ipv4_traffic && conn->entry_cfg.ipv6_traffic) { tor_addr_make_null(&addr, AF_INET6); addrp = &addr; } else if (conn->entry_cfg.ipv4_traffic && !conn->entry_cfg.ipv6_traffic) { tor_addr_make_null(&addr, AF_INET); addrp = &addr; } r = compare_tor_addr_to_node_policy(addrp, conn->socks_request->port, exit_node); if (r == ADDR_POLICY_REJECTED) return 0; /* We know the address, and the exit policy rejects it. */ if (r == ADDR_POLICY_PROBABLY_REJECTED && !conn->chosen_exit_name) return 0; /* We don't know the addr, but the exit policy rejects most * addresses with this port. Since the user didn't ask for * this node, err on the side of caution. */ } else if (SOCKS_COMMAND_IS_RESOLVE(conn->socks_request->command)) { /* Don't send DNS requests to non-exit servers by default. */ if (!conn->chosen_exit_name && node_exit_policy_rejects_all(exit_node)) return 0; } if (routerset_contains_node(options->ExcludeExitNodesUnion_, exit_node)) { /* Not a suitable exit. Refuse it. */ return 0; } return 1; } /** If address is of the form "y.onion" with a well-formed handle y: * Put a NUL after y, lower-case it, and return ONION_V2_HOSTNAME or * ONION_V3_HOSTNAME depending on the HS version. * * If address is of the form "x.y.onion" with a well-formed handle x: * Drop "x.", put a NUL after y, lower-case it, and return * ONION_V2_HOSTNAME or ONION_V3_HOSTNAME depending on the HS version. * * If address is of the form "y.onion" with a badly-formed handle y: * Return BAD_HOSTNAME and log a message. * * If address is of the form "y.exit": * Put a NUL after y and return EXIT_HOSTNAME. * * Otherwise: * Return NORMAL_HOSTNAME and change nothing. */ hostname_type_t parse_extended_hostname(char *address) { char *s; char *q; char query[HS_SERVICE_ADDR_LEN_BASE32+1]; s = strrchr(address,'.'); if (!s) return NORMAL_HOSTNAME; /* no dot, thus normal */ if (!strcmp(s+1,"exit")) { *s = 0; /* NUL-terminate it */ return EXIT_HOSTNAME; /* .exit */ } if (strcmp(s+1,"onion")) return NORMAL_HOSTNAME; /* neither .exit nor .onion, thus normal */ /* so it is .onion */ *s = 0; /* NUL-terminate it */ /* locate a 'sub-domain' component, in order to remove it */ q = strrchr(address, '.'); if (q == address) { goto failed; /* reject sub-domain, as DNS does */ } q = (NULL == q) ? address : q + 1; if (strlcpy(query, q, HS_SERVICE_ADDR_LEN_BASE32+1) >= HS_SERVICE_ADDR_LEN_BASE32+1) goto failed; if (q != address) { memmove(address, q, strlen(q) + 1 /* also get \0 */); } if (rend_valid_v2_service_id(query)) { return ONION_V2_HOSTNAME; /* success */ } if (hs_address_is_valid(query)) { return ONION_V3_HOSTNAME; } failed: /* otherwise, return to previous state and return 0 */ *s = '.'; log_warn(LD_APP, "Invalid onion hostname %s; rejecting", safe_str_client(address)); return BAD_HOSTNAME; } /** Return true iff the (possibly NULL) alen-byte chunk of memory at * a is equal to the (possibly NULL) blen-byte chunk of memory * at b. */ static int memeq_opt(const char *a, size_t alen, const char *b, size_t blen) { if (a == NULL) { return (b == NULL); } else if (b == NULL) { return 0; } else if (alen != blen) { return 0; } else { return tor_memeq(a, b, alen); } } /** * Return true iff none of the isolation flags and fields in conn * should prevent it from being attached to circ. */ int connection_edge_compatible_with_circuit(const entry_connection_t *conn, const origin_circuit_t *circ) { const uint8_t iso = conn->entry_cfg.isolation_flags; const socks_request_t *sr = conn->socks_request; /* If circ has never been used for an isolated connection, we can * totally use it for this one. */ if (!circ->isolation_values_set) return 1; /* If circ has been used for connections having more than one value * for some field f, it will have the corresponding bit set in * isolation_flags_mixed. If isolation_flags_mixed has any bits * in common with iso, then conn must be isolated from at least * one stream that has been attached to circ. */ if ((iso & circ->isolation_flags_mixed) != 0) { /* For at least one field where conn is isolated, the circuit * already has mixed streams. */ return 0; } if (! conn->original_dest_address) { log_warn(LD_BUG, "Reached connection_edge_compatible_with_circuit without " "having set conn->original_dest_address"); ((entry_connection_t*)conn)->original_dest_address = tor_strdup(conn->socks_request->address); } if ((iso & ISO_STREAM) && (circ->associated_isolated_stream_global_id != ENTRY_TO_CONN(conn)->global_identifier)) return 0; if ((iso & ISO_DESTPORT) && conn->socks_request->port != circ->dest_port) return 0; if ((iso & ISO_DESTADDR) && strcasecmp(conn->original_dest_address, circ->dest_address)) return 0; if ((iso & ISO_SOCKSAUTH) && (! memeq_opt(sr->username, sr->usernamelen, circ->socks_username, circ->socks_username_len) || ! memeq_opt(sr->password, sr->passwordlen, circ->socks_password, circ->socks_password_len))) return 0; if ((iso & ISO_CLIENTPROTO) && (conn->socks_request->listener_type != circ->client_proto_type || conn->socks_request->socks_version != circ->client_proto_socksver)) return 0; if ((iso & ISO_CLIENTADDR) && !tor_addr_eq(&ENTRY_TO_CONN(conn)->addr, &circ->client_addr)) return 0; if ((iso & ISO_SESSIONGRP) && conn->entry_cfg.session_group != circ->session_group) return 0; if ((iso & ISO_NYM_EPOCH) && conn->nym_epoch != circ->nym_epoch) return 0; return 1; } /** * If dry_run is false, update circ's isolation flags and fields * to reflect having had conn attached to it, and return 0. Otherwise, * if dry_run is true, then make no changes to circ, and return * a bitfield of isolation flags that we would have to set in * isolation_flags_mixed to add conn to circ, or -1 if * circ has had no streams attached to it. */ int connection_edge_update_circuit_isolation(const entry_connection_t *conn, origin_circuit_t *circ, int dry_run) { const socks_request_t *sr = conn->socks_request; if (! conn->original_dest_address) { log_warn(LD_BUG, "Reached connection_update_circuit_isolation without " "having set conn->original_dest_address"); ((entry_connection_t*)conn)->original_dest_address = tor_strdup(conn->socks_request->address); } if (!circ->isolation_values_set) { if (dry_run) return -1; circ->associated_isolated_stream_global_id = ENTRY_TO_CONN(conn)->global_identifier; circ->dest_port = conn->socks_request->port; circ->dest_address = tor_strdup(conn->original_dest_address); circ->client_proto_type = conn->socks_request->listener_type; circ->client_proto_socksver = conn->socks_request->socks_version; tor_addr_copy(&circ->client_addr, &ENTRY_TO_CONN(conn)->addr); circ->session_group = conn->entry_cfg.session_group; circ->nym_epoch = conn->nym_epoch; circ->socks_username = sr->username ? tor_memdup(sr->username, sr->usernamelen) : NULL; circ->socks_password = sr->password ? tor_memdup(sr->password, sr->passwordlen) : NULL; circ->socks_username_len = sr->usernamelen; circ->socks_password_len = sr->passwordlen; circ->isolation_values_set = 1; return 0; } else { uint8_t mixed = 0; if (conn->socks_request->port != circ->dest_port) mixed |= ISO_DESTPORT; if (strcasecmp(conn->original_dest_address, circ->dest_address)) mixed |= ISO_DESTADDR; if (!memeq_opt(sr->username, sr->usernamelen, circ->socks_username, circ->socks_username_len) || !memeq_opt(sr->password, sr->passwordlen, circ->socks_password, circ->socks_password_len)) mixed |= ISO_SOCKSAUTH; if ((conn->socks_request->listener_type != circ->client_proto_type || conn->socks_request->socks_version != circ->client_proto_socksver)) mixed |= ISO_CLIENTPROTO; if (!tor_addr_eq(&ENTRY_TO_CONN(conn)->addr, &circ->client_addr)) mixed |= ISO_CLIENTADDR; if (conn->entry_cfg.session_group != circ->session_group) mixed |= ISO_SESSIONGRP; if (conn->nym_epoch != circ->nym_epoch) mixed |= ISO_NYM_EPOCH; if (dry_run) return mixed; if ((mixed & conn->entry_cfg.isolation_flags) != 0) { log_warn(LD_BUG, "Updating a circuit with seemingly incompatible " "isolation flags."); } circ->isolation_flags_mixed |= mixed; return 0; } } /** * Clear the isolation settings on circ. * * This only works on an open circuit that has never had a stream attached to * it, and whose isolation settings are hypothetical. (We set hypothetical * isolation settings on circuits as we're launching them, so that we * know whether they can handle more streams or whether we need to launch * even more circuits. Once the circuit is open, if it turns out that * we no longer have any streams to attach to it, we clear the isolation flags * and data so that other streams can have a chance.) */ void circuit_clear_isolation(origin_circuit_t *circ) { if (circ->isolation_any_streams_attached) { log_warn(LD_BUG, "Tried to clear the isolation status of a dirty circuit"); return; } if (TO_CIRCUIT(circ)->state != CIRCUIT_STATE_OPEN) { log_warn(LD_BUG, "Tried to clear the isolation status of a non-open " "circuit"); return; } circ->isolation_values_set = 0; circ->isolation_flags_mixed = 0; circ->associated_isolated_stream_global_id = 0; circ->client_proto_type = 0; circ->client_proto_socksver = 0; circ->dest_port = 0; tor_addr_make_unspec(&circ->client_addr); tor_free(circ->dest_address); circ->session_group = -1; circ->nym_epoch = 0; if (circ->socks_username) { memwipe(circ->socks_username, 0x11, circ->socks_username_len); tor_free(circ->socks_username); } if (circ->socks_password) { memwipe(circ->socks_password, 0x05, circ->socks_password_len); tor_free(circ->socks_password); } circ->socks_username_len = circ->socks_password_len = 0; } /** Free all storage held in module-scoped variables for connection_edge.c */ void connection_edge_free_all(void) { untried_pending_connections = 0; smartlist_free(pending_entry_connections); pending_entry_connections = NULL; mainloop_event_free(attach_pending_entry_connections_ev); }