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- /* Copyright 2001 Matej Pfajfar.
- * Copyright 2001-2004 Roger Dingledine.
- * Copyright 2004-2005 Roger Dingledine, Nick Mathewson. */
- /* See LICENSE for licensing information */
- /* $Id$ */
- const char connection_edge_c_id[] = "$Id$";
- /**
- * \file connection_edge.c
- * \brief Handle edge streams.
- **/
- #include "or.h"
- #include "tree.h"
- static addr_policy_t *socks_policy = NULL;
- /* List of exit_redirect_t */
- static smartlist_t *redirect_exit_list = NULL;
- static int connection_ap_handshake_process_socks(connection_t *conn);
- static int address_is_in_virtual_range(const char *addr);
- /** 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.
- */
- void
- connection_close_unattached_ap(connection_t *conn, int endreason) {
- tor_assert(conn->type == CONN_TYPE_AP);
- conn->has_sent_end = 1; /* no circ yet */
- if (!conn->socks_request->has_finished) {
- socks5_reply_status_t socksreason =
- connection_edge_end_reason_socks5_response(endreason);
- //XXX Bug: it's not marked for close yet, so the below things won't
- // be defined yet. -RD
- if (endreason == END_STREAM_REASON_ALREADY_SOCKS_REPLIED)
- log_fn(LOG_WARN,"Bug: stream (marked at %s:%d) sending two socks replies?",
- conn->marked_for_close_file?conn->marked_for_close_file:"",
- conn->marked_for_close);
- if (conn->socks_request->command == SOCKS_COMMAND_CONNECT)
- connection_ap_handshake_socks_reply(conn, NULL, 0, socksreason);
- else
- connection_ap_handshake_socks_resolved(conn,RESOLVED_TYPE_ERROR,0,NULL);
- }
- //XXX Bug: this means that marked-for-close-file and marked-for-close
- // will all be defined as being inside this function. that's not what
- // we had in mind. -RD
- connection_mark_for_close(conn);
- conn->hold_open_until_flushed = 1;
- }
- /** There was an EOF. Send an end and mark the connection for close.
- */
- int connection_edge_reached_eof(connection_t *conn) {
- #ifdef HALF_OPEN
- /* eof reached; we're done reading, but we might want to write more. */
- conn->done_receiving = 1;
- shutdown(conn->s, 0); /* XXX check return, refactor NM */
- if (conn->done_sending) {
- connection_edge_end(conn, END_STREAM_REASON_DONE, conn->cpath_layer);
- connection_mark_for_close(conn);
- } else {
- connection_edge_send_command(conn, circuit_get_by_conn(conn), RELAY_COMMAND_END,
- NULL, 0, conn->cpath_layer);
- }
- return 0;
- #else
- if (buf_datalen(conn->inbuf) && connection_state_is_open(conn)) {
- /* it still has stuff to process. don't let it die yet. */
- return 0;
- }
- log_fn(LOG_INFO,"conn (fd %d) reached eof (stream size %d). Closing.", conn->s, (int)conn->stream_size);
- if (!conn->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, conn->cpath_layer);
- if (conn->socks_request) /* eof, so don't send a socks reply back */
- conn->socks_request->has_finished = 1;
- connection_mark_for_close(conn);
- }
- return 0;
- #endif
- }
- /** 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 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(connection_t *conn, int package_partial) {
- tor_assert(conn);
- tor_assert(CONN_IS_EDGE(conn));
- switch (conn->state) {
- case AP_CONN_STATE_SOCKS_WAIT:
- if (connection_ap_handshake_process_socks(conn) < 0) {
- /* already marked */
- return -1;
- }
- return 0;
- case AP_CONN_STATE_OPEN:
- case EXIT_CONN_STATE_OPEN:
- if (connection_edge_package_raw_inbuf(conn, package_partial) < 0) {
- /* (We already sent an end cell if possible) */
- connection_mark_for_close(conn);
- return -1;
- }
- return 0;
- case EXIT_CONN_STATE_CONNECTING:
- case AP_CONN_STATE_RENDDESC_WAIT:
- case AP_CONN_STATE_CIRCUIT_WAIT:
- case AP_CONN_STATE_CONNECT_WAIT:
- case AP_CONN_STATE_RESOLVE_WAIT:
- case AP_CONN_STATE_CONTROLLER_WAIT:
- log_fn(LOG_INFO,"data from edge while in '%s' state. Leaving it on buffer.",
- conn_state_to_string[conn->type][conn->state]);
- return 0;
- }
- log_fn(LOG_WARN,"Bug: Got unexpected state %d. Closing.",conn->state);
- #ifdef TOR_FRAGILE
- tor_assert(0);
- #endif
- connection_edge_end(conn, END_STREAM_REASON_INTERNAL, conn->cpath_layer);
- connection_mark_for_close(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(uint16_t circ_id, connection_t *conn) {
- tor_assert(CONN_IS_EDGE(conn));
- if (conn->marked_for_close)
- return 0; /* already marked; probably got an 'end' */
- log_fn(LOG_INFO,"CircID %d: At an edge. Marking connection for close.",
- circ_id);
- if (conn->type == CONN_TYPE_AP) {
- connection_close_unattached_ap(conn, END_STREAM_REASON_DESTROY);
- } else {
- conn->has_sent_end = 1; /* we're closing the circuit, nothing to send to */
- connection_mark_for_close(conn);
- conn->hold_open_until_flushed = 1;
- }
- conn->cpath_layer = NULL;
- return 0;
- }
- /** Send a relay end cell from stream <b>conn</b> to conn's circuit,
- * with a destination of cpath_layer. (If cpath_layer is NULL, the
- * destination is the circuit's origin.) Mark the relay end cell as
- * closing because of <b>reason</b>.
- *
- * Return -1 if this function has already been called on this conn,
- * else return 0.
- */
- int
- connection_edge_end(connection_t *conn, char reason, crypt_path_t *cpath_layer)
- {
- char payload[5];
- size_t payload_len=1;
- circuit_t *circ;
- if (conn->has_sent_end) {
- log_fn(LOG_WARN,"Harmless bug: Calling connection_edge_end (reason %d) on an already ended stream?", reason);
- #ifdef TOR_FRAGILE
- tor_assert(0);
- #endif
- return -1;
- }
- if (conn->marked_for_close) {
- log_fn(LOG_WARN,"Bug: called on conn that's already marked for close at %s:%d.",
- conn->marked_for_close_file, conn->marked_for_close);
- return 0;
- }
- payload[0] = reason;
- if (reason == END_STREAM_REASON_EXITPOLICY) {
- /* this is safe even for rend circs, because they never fail
- * because of exitpolicy */
- set_uint32(payload+1, htonl(conn->addr));
- payload_len += 4;
- }
- circ = circuit_get_by_conn(conn);
- if (circ && !circ->marked_for_close) {
- log_fn(LOG_DEBUG,"Marking conn (fd %d) and sending end.",conn->s);
- connection_edge_send_command(conn, circ, RELAY_COMMAND_END,
- payload, payload_len, cpath_layer);
- } else {
- log_fn(LOG_DEBUG,"Marking conn (fd %d); no circ to send end.",conn->s);
- }
- conn->has_sent_end = 1;
- return 0;
- }
- /** An error has just occured on an operation on an edge connection
- * <b>conn</b>. Extract the errno; convert it to an end reason, and send
- * an appropriate relay end cell to <b>cpath_layer</b>.
- **/
- int
- connection_edge_end_errno(connection_t *conn, crypt_path_t *cpath_layer)
- {
- uint8_t reason;
- tor_assert(conn);
- reason = (uint8_t)errno_to_end_reason(tor_socket_errno(conn->s));
- return connection_edge_end(conn, reason, cpath_layer);
- }
- /** Connection <b>conn</b> 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 <b>conn</b> is broken, mark it for close and return -1, else
- * return 0.
- */
- int connection_edge_finished_flushing(connection_t *conn) {
- tor_assert(conn);
- tor_assert(CONN_IS_EDGE(conn));
- switch (conn->state) {
- case AP_CONN_STATE_OPEN:
- case EXIT_CONN_STATE_OPEN:
- connection_stop_writing(conn);
- connection_edge_consider_sending_sendme(conn);
- return 0;
- case AP_CONN_STATE_SOCKS_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:
- connection_stop_writing(conn);
- return 0;
- default:
- log_fn(LOG_WARN,"BUG: called in unexpected state %d.", conn->state);
- #ifdef TOR_FRAGILE
- tor_assert(0);
- #endif
- return -1;
- }
- return 0;
- }
- /** 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(connection_t *conn)
- {
- unsigned char connected_payload[4];
- tor_assert(conn);
- tor_assert(conn->type == CONN_TYPE_EXIT);
- tor_assert(conn->state == EXIT_CONN_STATE_CONNECTING);
- log_fn(LOG_INFO,"Exit connection to %s:%u established.",
- conn->address,conn->port);
- conn->state = EXIT_CONN_STATE_OPEN;
- connection_watch_events(conn, EV_READ); /* stop writing, continue reading */
- if (connection_wants_to_flush(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(conn)) {
- if (connection_edge_send_command(conn, circuit_get_by_conn(conn),
- RELAY_COMMAND_CONNECTED, NULL, 0, conn->cpath_layer) < 0)
- return 0; /* circuit is closed, don't continue */
- } else {
- *(uint32_t*)connected_payload = htonl(conn->addr);
- if (connection_edge_send_command(conn, circuit_get_by_conn(conn),
- RELAY_COMMAND_CONNECTED, connected_payload, 4, conn->cpath_layer) < 0)
- return 0; /* circuit is closed, don't continue */
- }
- tor_assert(conn->package_window > 0);
- /* in case the server has written anything */
- return connection_edge_process_inbuf(conn, 1);
- }
- /** Find all general-purpose AP streams waiting for a response that sent
- * their begin/resolve cell >=15 seconds 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 45 seconds (with no
- * retry attempt).
- */
- void connection_ap_expire_beginning(void) {
- connection_t **carray;
- connection_t *conn;
- circuit_t *circ;
- int n, i;
- time_t now = time(NULL);
- or_options_t *options = get_options();
- get_connection_array(&carray, &n);
- for (i = 0; i < n; ++i) {
- conn = carray[i];
- if (conn->type != CONN_TYPE_AP)
- continue;
- if (conn->state == AP_CONN_STATE_CONTROLLER_WAIT) {
- if (now - conn->timestamp_lastread >= 120) {
- log_fn(LOG_NOTICE, "Closing unattached stream.");
- connection_close_unattached_ap(conn, END_STREAM_REASON_TIMEOUT);
- }
- continue;
- }
- else if (conn->state != AP_CONN_STATE_RESOLVE_WAIT &&
- conn->state != AP_CONN_STATE_CONNECT_WAIT)
- continue;
- if (now - conn->timestamp_lastread < 15)
- continue;
- circ = circuit_get_by_conn(conn);
- if (!circ) { /* it's vanished? */
- log_fn(LOG_INFO,"Conn is waiting (address %s), but lost its circ.",
- conn->socks_request->address);
- connection_close_unattached_ap(conn, END_STREAM_REASON_TIMEOUT);
- continue;
- }
- if (circ->purpose == CIRCUIT_PURPOSE_C_REND_JOINED) {
- if (now - conn->timestamp_lastread > 45) {
- log_fn(LOG_NOTICE,"Rend stream is %d seconds late. Giving up on address '%s'.",
- (int)(now - conn->timestamp_lastread), conn->socks_request->address);
- connection_edge_end(conn, END_STREAM_REASON_TIMEOUT, conn->cpath_layer);
- connection_close_unattached_ap(conn, END_STREAM_REASON_TIMEOUT);
- }
- continue;
- }
- tor_assert(circ->purpose == CIRCUIT_PURPOSE_C_GENERAL);
- log_fn(LOG_NOTICE,"Stream is %d seconds late on address '%s'. Retrying.",
- (int)(now - conn->timestamp_lastread), conn->socks_request->address);
- circuit_log_path(LOG_NOTICE, circ);
- /* send an end down the circuit */
- connection_edge_end(conn, END_STREAM_REASON_TIMEOUT, conn->cpath_layer);
- /* un-mark it as ending, since we're going to reuse it */
- conn->has_sent_end = 0;
- /* kludge to make us not try this circuit again, yet to allow
- * current streams on it to survive if they can: make it
- * unattractive to use for new streams */
- tor_assert(circ->timestamp_dirty);
- circ->timestamp_dirty -= options->MaxCircuitDirtiness;
- /* give our stream another 15 seconds to try */
- conn->timestamp_lastread += 15;
- /* move it back into 'pending' state, and try to attach. */
- if (connection_ap_detach_retriable(conn, circ)<0) {
- connection_close_unattached_ap(conn, END_STREAM_REASON_CANT_ATTACH);
- }
- } /* end for */
- }
- /** Tell any AP streams that are waiting for a new circuit that one is
- * available.
- */
- void connection_ap_attach_pending(void)
- {
- connection_t **carray;
- connection_t *conn;
- int n, i;
- get_connection_array(&carray, &n);
- for (i = 0; i < n; ++i) {
- conn = carray[i];
- if (conn->marked_for_close ||
- conn->type != CONN_TYPE_AP ||
- conn->state != AP_CONN_STATE_CIRCUIT_WAIT)
- continue;
- if (connection_ap_handshake_attach_circuit(conn) < 0) {
- connection_close_unattached_ap(conn, END_STREAM_REASON_CANT_ATTACH);
- }
- }
- }
- /** The AP connection <b>conn</b> has just failed while attaching or
- * sending a BEGIN or resolving on <b>circ</b>, but another circuit
- * might work. Detach the circuit, and either reattach it, launch a
- * new circuit, tell the controller, or give up as a appropriate.
- *
- * Returns -1 on err, 1 on success, 0 on not-yet-sure.
- */
- int
- connection_ap_detach_retriable(connection_t *conn, circuit_t *circ)
- {
- control_event_stream_status(conn, STREAM_EVENT_FAILED_RETRIABLE);
- conn->timestamp_lastread = time(NULL);
- if (! get_options()->LeaveStreamsUnattached) {
- conn->state = AP_CONN_STATE_CIRCUIT_WAIT;
- circuit_detach_stream(circ,conn);
- return connection_ap_handshake_attach_circuit(conn);
- } else {
- conn->state = AP_CONN_STATE_CONTROLLER_WAIT;
- circuit_detach_stream(circ,conn);
- return 0;
- }
- }
- /** A client-side struct to remember requests to rewrite addresses
- * to new addresses. These structs make up a tree, with addressmap
- * below as its root.
- *
- * There are 5 ways to set an address mapping:
- * - A MapAddress command from the controller [permanent]
- * - An AddressMap directive in the torrc [permanent]
- * - When a TrackHostExits torrc directive is triggered [temporary]
- * - When a dns resolve succeeds [temporary]
- * - When a dns resolve fails [temporary]
- *
- * When an addressmap request is made but one is already registered,
- * the new one is replaced only if the currently registered one has
- * no "new_address" (that is, it's in the process of dns resolve),
- * or if the new one is permanent (expires==0 or 1).
- *
- * (We overload the 'expires' field, using "0" for mappings set via
- * the configuration file, "1" for mappings set from the control
- * interface, and other values for DNS mappings that can expire.)
- */
- typedef struct {
- char *new_address;
- time_t expires;
- int num_resolve_failures;
- } addressmap_entry_t;
- typedef struct {
- char *ipv4_address;
- char *hostname_address;
- } virtaddress_entry_t;
- /** The tree of client-side address rewrite instructions. */
- static strmap_t *addressmap=NULL;
- /**
- * Tree mapping addresses to which virtual address, if any, we
- * assigned them to.
- *
- * We maintain the following invariant: if [A,B] is in
- * virtaddress_reversemap, then B must be a virtual address, and [A,B]
- * must be in addressmap. We do not require that the converse hold:
- * if it fails, then we could end up mapping two virtual addresses to
- * the same address, which is no disaster.
- **/
- static strmap_t *virtaddress_reversemap=NULL;
- /** Initialize addressmap. */
- void addressmap_init(void) {
- addressmap = strmap_new();
- virtaddress_reversemap = strmap_new();
- }
- /** Free the memory associated with the addressmap entry <b>_ent</b>. */
- static void
- addressmap_ent_free(void *_ent) {
- addressmap_entry_t *ent = _ent;
- tor_free(ent->new_address);
- tor_free(ent);
- }
- static void
- addressmap_virtaddress_ent_free(void *_ent) {
- virtaddress_entry_t *ent = _ent;
- tor_free(ent->ipv4_address);
- tor_free(ent->hostname_address);
- tor_free(ent);
- }
- static void
- addressmap_virtaddress_remove(const char *addr, addressmap_entry_t *ent)
- {
- if (ent && ent->new_address && address_is_in_virtual_range(ent->new_address)) {
- virtaddress_entry_t *ve =
- strmap_get(virtaddress_reversemap, ent->new_address);
- /*log_fn(LOG_NOTICE,"remove reverse mapping for %s",ent->new_address);*/
- if (ve) {
- if (!strcmp(addr, ve->ipv4_address))
- tor_free(ve->ipv4_address);
- if (!strcmp(addr, ve->hostname_address))
- tor_free(ve->hostname_address);
- if (!ve->ipv4_address && !ve->hostname_address) {
- tor_free(ve);
- strmap_remove(virtaddress_reversemap, ent->new_address);
- }
- }
- }
- }
- static void
- addressmap_ent_remove(const char *addr, addressmap_entry_t *ent)
- {
- addressmap_virtaddress_remove(addr, ent);
- addressmap_ent_free(ent);
- }
- /** Remove all entries from the addressmap that were set via the
- * configuration file or the command line. */
- void
- addressmap_clear_configured(void)
- {
- addressmap_get_mappings(NULL, 0, 0);
- }
- /** Remove all entries from the addressmap that are set to expire, ever. */
- void
- addressmap_clear_transient(void)
- {
- addressmap_get_mappings(NULL, 2, TIME_MAX);
- }
- /** Clean out entries from the addressmap cache that were
- * added long enough ago that they are no longer valid.
- */
- void addressmap_clean(time_t now) {
- addressmap_get_mappings(NULL, 2, now);
- }
- /** Free all the elements in the addressmap, and free the addressmap
- * itself. */
- void addressmap_free_all(void) {
- strmap_free(addressmap, addressmap_ent_free);
- addressmap = NULL;
- strmap_free(virtaddress_reversemap, addressmap_virtaddress_ent_free);
- }
- /** Look at address, and rewrite it until it doesn't want any
- * more rewrites; but don't get into an infinite loop.
- * Don't write more than maxlen chars into address.
- */
- void addressmap_rewrite(char *address, size_t maxlen) {
- addressmap_entry_t *ent;
- int rewrites;
- for (rewrites = 0; rewrites < 16; rewrites++) {
- ent = strmap_get(addressmap, address);
- if (!ent || !ent->new_address)
- return; /* done, no rewrite needed */
- log_fn(LOG_INFO, "Addressmap: rewriting '%s' to '%s'",
- address, ent->new_address);
- strlcpy(address, ent->new_address, maxlen);
- }
- log_fn(LOG_WARN,"Loop detected: we've rewritten '%s' 16 times! Using it as-is.",
- address);
- /* it's fine to rewrite a rewrite, but don't loop forever */
- }
- /** Return 1 if <b>address</b> is already registered, else return 0 */
- int addressmap_already_mapped(const char *address) {
- return strmap_get(addressmap, address) ? 1 : 0;
- }
- /** Register a request to map <b>address</b> to <b>new_address</b>,
- * which will expire on <b>expires</b> (or 0 if never expires from
- * config file, 1 if never expires from controller, 2 if never expires
- * (virtual address mapping) from the controller.)
- *
- * <b>new_address</b> should be a newly dup'ed string, which we'll use or
- * free as appropriate. We will leave address alone.
- *
- * If <b>new_address</b> is NULL, or equal to <b>address</b>, remove
- * any mappings that exist from <b>address</b>.
- */
- void addressmap_register(const char *address, char *new_address, time_t expires) {
- addressmap_entry_t *ent;
- ent = strmap_get(addressmap, address);
- if (!new_address || !strcasecmp(address,new_address)) {
- /* Remove the mapping, if any. */
- tor_free(new_address);
- if (ent) {
- addressmap_ent_remove(address,ent);
- strmap_remove(addressmap, address);
- }
- return;
- }
- if (!ent) { /* make a new one and register it */
- ent = tor_malloc_zero(sizeof(addressmap_entry_t));
- strmap_set(addressmap, address, ent);
- } else if (ent->new_address) { /* we need to clean up the old mapping. */
- if (expires > 1) {
- log_fn(LOG_INFO,"Temporary addressmap ('%s' to '%s') not performed, since it's already mapped to '%s'", address, new_address, ent->new_address);
- tor_free(new_address);
- return;
- }
- if (address_is_in_virtual_range(ent->new_address) &&
- expires != 2) {
- /* XXX This isn't the perfect test; we want to avoid removing
- * mappings set from the control interface _as virtual mapping */
- addressmap_virtaddress_remove(address, ent);
- }
- tor_free(ent->new_address);
- } /* else { we have an in-progress resolve with no mapping. } */
- ent->new_address = new_address;
- ent->expires = expires==2 ? 1 : expires;
- ent->num_resolve_failures = 0;
- log_fn(LOG_INFO, "Addressmap: (re)mapped '%s' to '%s'",
- address, ent->new_address);
- }
- /** An attempt to resolve <b>address</b> failed at some OR.
- * Increment the number of resolve failures we have on record
- * for it, and then return that number.
- */
- int client_dns_incr_failures(const char *address)
- {
- addressmap_entry_t *ent;
- ent = strmap_get(addressmap,address);
- if (!ent) {
- ent = tor_malloc_zero(sizeof(addressmap_entry_t));
- ent->expires = time(NULL)+MAX_DNS_ENTRY_AGE;
- strmap_set(addressmap,address,ent);
- }
- ++ent->num_resolve_failures;
- log_fn(LOG_INFO,"Address %s now has %d resolve failures.",
- address, ent->num_resolve_failures);
- return ent->num_resolve_failures;
- }
- /** Record the fact that <b>address</b> resolved to <b>val</b>.
- * We can now use this in subsequent streams via addressmap_rewrite()
- * so we can more correctly choose an exit that will allow <b>address</b>.
- *
- * If <b>exitname</b> is defined, then append the addresses with
- * ".exitname.exit" before registering the mapping.
- */
- void client_dns_set_addressmap(const char *address, uint32_t val, const char *exitname)
- {
- struct in_addr in;
- char extendedaddress[MAX_SOCKS_ADDR_LEN+MAX_HEX_NICKNAME_LEN+10];
- char valbuf[INET_NTOA_BUF_LEN];
- char extendedval[INET_NTOA_BUF_LEN+MAX_HEX_NICKNAME_LEN+10];
- tor_assert(address); tor_assert(val);
- if (tor_inet_aton(address, &in))
- return; /* If address was an IP address already, don't add a mapping. */
- in.s_addr = htonl(val);
- tor_inet_ntoa(&in,valbuf,sizeof(valbuf));
- if (exitname) {
- tor_snprintf(extendedaddress, sizeof(extendedaddress),
- "%s.%s.exit", address, exitname);
- tor_snprintf(extendedval, sizeof(extendedval),
- "%s.%s.exit", valbuf, exitname);
- } else {
- tor_snprintf(extendedaddress, sizeof(extendedaddress),
- "%s", address);
- tor_snprintf(extendedval, sizeof(extendedval),
- "%s", valbuf);
- }
- addressmap_register(extendedaddress, tor_strdup(extendedval),
- time(NULL) + MAX_DNS_ENTRY_AGE);
- }
- /* Currently, we hand out 127.192.0.1 through 127.254.254.254.
- * These addresses should map to localhost, so even if the
- * application accidentally tried to connect to them directly (not
- * via Tor), it wouldn't get too far astray.
- *
- * Eventually, we should probably make this configurable.
- */
- #define MIN_UNUSED_IPV4 0x7fc00001u
- #define MAX_UNUSED_IPV4 0x7ffefefeu
- /**
- * Return true iff <b>addr</b> is likely to have been returned by
- * client_dns_get_unused_address.
- **/
- static int
- address_is_in_virtual_range(const char *addr)
- {
- struct in_addr in;
- tor_assert(addr);
- if (!strcasecmpend(addr, ".virtual")) {
- return 1;
- } else if (tor_inet_aton(addr, &in)) {
- uint32_t a = ntohl(in.s_addr);
- if (a >= MIN_UNUSED_IPV4 && a <= MAX_UNUSED_IPV4)
- return 1;
- }
- return 0;
- }
- /** Return a newly allocated string holding an address of <b>type</b>
- * (one of RESOLVED_TYPE_{IPV4|HOSTNAME}) that has not yet been mapped,
- * and that is very unlikely to be the address of any real host.
- */
- static char *
- addressmap_get_virtual_address(int type)
- {
- char buf[64];
- static uint32_t next_ipv4 = MIN_UNUSED_IPV4;
- struct in_addr in;
- if (type == RESOLVED_TYPE_HOSTNAME) {
- char rand[10];
- do {
- crypto_rand(rand, sizeof(rand));
- base32_encode(buf,sizeof(buf),rand,sizeof(rand));
- strlcat(buf, ".virtual", sizeof(buf));
- } while (strmap_get(addressmap, buf));
- return tor_strdup(buf);
- } else if (type == RESOLVED_TYPE_IPV4) {
- while (1) {
- /* Don't hand out any .0 or .255 address. */
- while ((next_ipv4 & 0xff) == 0 ||
- (next_ipv4 & 0xff) == 0xff)
- ++next_ipv4;
- in.s_addr = htonl(next_ipv4);
- tor_inet_ntoa(&in, buf, sizeof(buf));
- if (!strmap_get(addressmap, buf))
- break;
- ++next_ipv4;
- if (next_ipv4 > MAX_UNUSED_IPV4)
- next_ipv4 = MIN_UNUSED_IPV4;
- }
- return tor_strdup(buf);
- } else {
- log_fn(LOG_WARN, "Called with unsupported address type (%d)",
- type);
- return NULL;
- }
- }
- /** A controller has requested that we map some address of type
- * <b>type</b> to the address <b>new_address</b>. Choose an address
- * that is unlikely to be used, and map it, and return it in a newly
- * allocated string. If another address of the same type is already
- * mapped to <b>new_address</b>, try to return a copy of that address.
- *
- * The string in <b>new_address</b> may be freed, or inserted into a map
- * as appropriate.
- **/
- const char *
- addressmap_register_virtual_address(int type, char *new_address)
- {
- char **addrp;
- virtaddress_entry_t *vent;
- tor_assert(new_address);
- tor_assert(addressmap);
- tor_assert(virtaddress_reversemap);
- vent = strmap_get(virtaddress_reversemap, new_address);
- if (!vent) {
- vent = tor_malloc_zero(sizeof(virtaddress_entry_t));
- strmap_set(virtaddress_reversemap, new_address, vent);
- }
- addrp = (type == RESOLVED_TYPE_IPV4) ?
- &vent->ipv4_address : &vent->hostname_address;
- if (*addrp) {
- addressmap_entry_t *ent = strmap_get(addressmap, *addrp);
- if (ent && ent->new_address && !strcasecmp(new_address, ent->new_address)) {
- tor_free(new_address);
- return tor_strdup(*addrp);
- } else
- log_fn(LOG_WARN, "Internal confusion: I thought that '%s' was mapped to by '%s', but '%s' really maps to '%s'. This is a harmless bug.",
- new_address, *addrp, *addrp, ent?ent->new_address:"(nothing)");
- }
- tor_free(*addrp);
- *addrp = addressmap_get_virtual_address(type);
- addressmap_register(*addrp, new_address, 2);
- #if 0
- {
- addressmap_entry_t *ent;
- ent = strmap_get(addressmap, *addrp);
- tor_assert(ent);
- tor_assert(!strcasecmp(ent->new_address,new_address));
- vent = strmap_get(virtaddress_reversemap, new_address);
- tor_assert(vent);
- tor_assert(!strcasecmp(*addrp,
- (type == RESOLVED_TYPE_IPV4) ?
- vent->ipv4_address : vent->hostname_address));
- log_fn(LOG_INFO, "Map from %s to %s okay.",*addrp,new_address);
- }
- #endif
- return *addrp;
- }
- /** Return 1 if <b>address</b> has funny characters in it like
- * colons. Return 0 if it's fine.
- */
- static int
- address_is_invalid_destination(const char *address) {
- /* FFFF should flesh this out */
- if (strchr(address,':'))
- return 1;
- return 0;
- }
- /** Iterate over all address mapings which have expiry times between
- * min_expires and max_expires, inclusive. If sl is provided, add an
- * "old-addr new-addr" string to sl for each mapping. If sl is NULL,
- * remove the mappings.
- */
- void
- addressmap_get_mappings(smartlist_t *sl, time_t min_expires, time_t max_expires)
- {
- strmap_iter_t *iter;
- const char *key;
- void *_val;
- addressmap_entry_t *val;
- for (iter = strmap_iter_init(addressmap); !strmap_iter_done(iter); ) {
- strmap_iter_get(iter, &key, &_val);
- val = _val;
- if (val->expires >= min_expires && val->expires <= max_expires) {
- if (!sl) {
- addressmap_ent_remove(key, val);
- iter = strmap_iter_next_rmv(addressmap,iter);
- continue;
- } else if (val->new_address) {
- size_t len = strlen(key)+strlen(val->new_address)+2;
- char *line = tor_malloc(len);
- tor_snprintf(line, len, "%s %s", key, val->new_address);
- smartlist_add(sl, line);
- }
- }
- iter = strmap_iter_next(addressmap,iter);
- }
- }
- /** 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, and it's for a general circuit, then
- * try to attach it to a circuit (or launch one as needed). If it's for
- * a rendezvous circuit, then fetch a rendezvous descriptor first (or
- * attach/launch a circuit if the rendezvous descriptor is already here
- * and fresh enough).
- *
- * Return -1 if an unexpected error with conn (and it should be marked
- * for close), else return 0.
- */
- static int connection_ap_handshake_process_socks(connection_t *conn) {
- socks_request_t *socks;
- int sockshere;
- hostname_type_t addresstype;
- tor_assert(conn);
- tor_assert(conn->type == CONN_TYPE_AP);
- tor_assert(conn->state == AP_CONN_STATE_SOCKS_WAIT);
- tor_assert(conn->socks_request);
- socks = conn->socks_request;
- log_fn(LOG_DEBUG,"entered.");
- sockshere = fetch_from_buf_socks(conn->inbuf, socks);
- if (sockshere == 0) {
- if (socks->replylen) {
- connection_write_to_buf(socks->reply, socks->replylen, conn);
- socks->replylen = 0; /* zero it out so we can do another round of negotiation */
- } else {
- log_fn(LOG_DEBUG,"socks handshake not all here yet.");
- }
- return 0;
- } else if (sockshere == -1) {
- if (socks->replylen) { /* we should send reply back */
- log_fn(LOG_DEBUG,"reply is already set for us. Using it.");
- connection_ap_handshake_socks_reply(conn, socks->reply, socks->replylen,
- SOCKS5_GENERAL_ERROR);
- } else {
- log_fn(LOG_WARN,"Fetching socks handshake failed. Closing.");
- connection_ap_handshake_socks_reply(conn, NULL, 0, SOCKS5_GENERAL_ERROR);
- }
- connection_close_unattached_ap(conn, END_STREAM_REASON_ALREADY_SOCKS_REPLIED);
- return -1;
- } /* else socks handshake is done, continue processing */
- tor_strlower(socks->address); /* normalize it */
- /* For address map controls, remap the address */
- addressmap_rewrite(socks->address, sizeof(socks->address));
- if (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. We *don't* want to send
- * the address through tor; that's likely to fail, and may leak
- * information.
- */
- log_fn(LOG_WARN,"Missing mapping for virtual address '%s'. Refusing.",
- socks->address);
- connection_close_unattached_ap(conn, END_STREAM_REASON_INTERNAL);
- return -1;
- }
- /* Parse the address provided by SOCKS. Modify it in-place if it
- * specifies a hidden-service (.onion) or particular exit node (.exit).
- */
- addresstype = parse_extended_hostname(socks->address);
- if (addresstype == EXIT_HOSTNAME) {
- /* .exit -- modify conn to specify the exit node. */
- char *s = strrchr(socks->address,'.');
- if (!s || s[1] == '\0') {
- log_fn(LOG_WARN,"Malformed exit address '%s'. Refusing.", socks->address);
- connection_close_unattached_ap(conn, END_STREAM_REASON_TORPROTOCOL);
- return -1;
- }
- conn->chosen_exit_name = tor_strdup(s+1);
- *s = 0;
- }
- if (addresstype != ONION_HOSTNAME) {
- /* not a hidden-service request (i.e. normal or .exit) */
- if (address_is_invalid_destination(socks->address)) {
- log_fn(LOG_WARN,"Destination '%s' seems to be an invalid hostname. Failing.", socks->address);
- connection_close_unattached_ap(conn, END_STREAM_REASON_TORPROTOCOL);
- return -1;
- }
- if (socks->command == SOCKS_COMMAND_RESOLVE) {
- uint32_t answer;
- struct in_addr in;
- /* Reply to resolves immediately if we can. */
- if (strlen(socks->address) > RELAY_PAYLOAD_SIZE) {
- log_fn(LOG_WARN,"Address to be resolved is too large. Failing.");
- connection_ap_handshake_socks_resolved(conn,RESOLVED_TYPE_ERROR,0,NULL);
- connection_close_unattached_ap(conn, END_STREAM_REASON_ALREADY_SOCKS_REPLIED);
- return -1;
- }
- if (tor_inet_aton(socks->address, &in)) { /* see if it's an IP already */
- answer = in.s_addr;
- connection_ap_handshake_socks_resolved(conn,RESOLVED_TYPE_IPV4,4,
- (char*)&answer);
- connection_close_unattached_ap(conn, END_STREAM_REASON_ALREADY_SOCKS_REPLIED);
- return 0;
- }
- rep_hist_note_used_resolve(time(NULL)); /* help predict this next time */
- control_event_stream_status(conn, STREAM_EVENT_NEW_RESOLVE);
- } else { /* socks->command == SOCKS_COMMAND_CONNECT */
- if (socks->port == 0) {
- log_fn(LOG_NOTICE,"Application asked to connect to port 0. Refusing.");
- connection_close_unattached_ap(conn, END_STREAM_REASON_TORPROTOCOL);
- return -1;
- }
- rep_hist_note_used_port(socks->port, time(NULL)); /* help predict this next time */
- control_event_stream_status(conn, STREAM_EVENT_NEW);
- }
- if (! get_options()->LeaveStreamsUnattached) {
- conn->state = AP_CONN_STATE_CIRCUIT_WAIT;
- if (connection_ap_handshake_attach_circuit(conn) < 0) {
- connection_close_unattached_ap(conn, END_STREAM_REASON_CANT_ATTACH);
- return -1;
- }
- return 0;
- } else {
- conn->state = AP_CONN_STATE_CONTROLLER_WAIT;
- return 0;
- }
- } else {
- /* it's a hidden-service request */
- rend_cache_entry_t *entry;
- int r;
- if (socks->command == SOCKS_COMMAND_RESOLVE) {
- /* if it's a resolve request, fail it right now, rather than
- * building all the circuits and then realizing it won't work. */
- log_fn(LOG_WARN,"Resolve requests to hidden services not allowed. Failing.");
- connection_ap_handshake_socks_resolved(conn,RESOLVED_TYPE_ERROR,0,NULL);
- connection_close_unattached_ap(conn, END_STREAM_REASON_ALREADY_SOCKS_REPLIED);
- return -1;
- }
- strlcpy(conn->rend_query, socks->address, sizeof(conn->rend_query));
- log_fn(LOG_INFO,"Got a hidden service request for ID '%s'", conn->rend_query);
- /* see if we already have it cached */
- r = rend_cache_lookup_entry(conn->rend_query, &entry);
- if (r<0) {
- log_fn(LOG_WARN,"Invalid service descriptor %s", conn->rend_query);
- connection_close_unattached_ap(conn, END_STREAM_REASON_TORPROTOCOL);
- return -1;
- }
- if (r==0) {
- conn->state = AP_CONN_STATE_RENDDESC_WAIT;
- log_fn(LOG_INFO, "Unknown descriptor %s. Fetching.", conn->rend_query);
- rend_client_refetch_renddesc(conn->rend_query);
- return 0;
- }
- if (r>0) {
- #define NUM_SECONDS_BEFORE_REFETCH (60*15)
- if (time(NULL) - entry->received < NUM_SECONDS_BEFORE_REFETCH) {
- conn->state = AP_CONN_STATE_CIRCUIT_WAIT;
- log_fn(LOG_INFO, "Descriptor is here and fresh enough. Great.");
- if (connection_ap_handshake_attach_circuit(conn) < 0) {
- connection_close_unattached_ap(conn, END_STREAM_REASON_CANT_ATTACH);
- return -1;
- }
- return 0;
- } else {
- conn->state = AP_CONN_STATE_RENDDESC_WAIT;
- log_fn(LOG_INFO, "Stale descriptor %s. Refetching.", conn->rend_query);
- rend_client_refetch_renddesc(conn->rend_query);
- return 0;
- }
- }
- }
- return 0; /* unreached but keeps the compiler happy */
- }
- /** 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.
- */
- static uint16_t get_unique_stream_id_by_circ(circuit_t *circ) {
- connection_t *tmpconn;
- uint16_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_fn(LOG_WARN,"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;
- }
- /** 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.
- */
- int connection_ap_handshake_send_begin(connection_t *ap_conn, circuit_t *circ)
- {
- char payload[CELL_PAYLOAD_SIZE];
- int payload_len;
- tor_assert(ap_conn->type == CONN_TYPE_AP);
- tor_assert(ap_conn->state == AP_CONN_STATE_CIRCUIT_WAIT);
- tor_assert(ap_conn->socks_request);
- ap_conn->stream_id = get_unique_stream_id_by_circ(circ);
- if (ap_conn->stream_id==0) {
- connection_close_unattached_ap(ap_conn, END_STREAM_REASON_INTERNAL);
- circuit_mark_for_close(circ);
- return -1;
- }
- tor_snprintf(payload,RELAY_PAYLOAD_SIZE, "%s:%d",
- (circ->purpose == CIRCUIT_PURPOSE_C_GENERAL) ?
- ap_conn->socks_request->address : "",
- ap_conn->socks_request->port);
- payload_len = strlen(payload)+1;
- log_fn(LOG_DEBUG,"Sending relay cell to begin stream %d.",ap_conn->stream_id);
- if (connection_edge_send_command(ap_conn, circ, RELAY_COMMAND_BEGIN,
- payload, payload_len, ap_conn->cpath_layer) < 0)
- return -1; /* circuit is closed, don't continue */
- ap_conn->package_window = STREAMWINDOW_START;
- ap_conn->deliver_window = STREAMWINDOW_START;
- ap_conn->state = AP_CONN_STATE_CONNECT_WAIT;
- log_fn(LOG_INFO,"Address/port sent, ap socket %d, n_circ_id %d",
- ap_conn->s, circ->n_circ_id);
- control_event_stream_status(ap_conn, STREAM_EVENT_SENT_CONNECT);
- 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(connection_t *ap_conn, circuit_t *circ)
- {
- int payload_len;
- const char *string_addr;
- tor_assert(ap_conn->type == CONN_TYPE_AP);
- tor_assert(ap_conn->state == AP_CONN_STATE_CIRCUIT_WAIT);
- tor_assert(ap_conn->socks_request);
- tor_assert(ap_conn->socks_request->command == SOCKS_COMMAND_RESOLVE);
- tor_assert(circ->purpose == CIRCUIT_PURPOSE_C_GENERAL);
- ap_conn->stream_id = get_unique_stream_id_by_circ(circ);
- if (ap_conn->stream_id==0) {
- connection_close_unattached_ap(ap_conn, END_STREAM_REASON_INTERNAL);
- circuit_mark_for_close(circ);
- return -1;
- }
- string_addr = ap_conn->socks_request->address;
- payload_len = strlen(string_addr)+1;
- tor_assert(payload_len <= RELAY_PAYLOAD_SIZE);
- log_fn(LOG_DEBUG,"Sending relay cell to begin stream %d.",ap_conn->stream_id);
- if (connection_edge_send_command(ap_conn, circ, RELAY_COMMAND_RESOLVE,
- string_addr, payload_len, ap_conn->cpath_layer) < 0)
- return -1; /* circuit is closed, don't continue */
- ap_conn->state = AP_CONN_STATE_RESOLVE_WAIT;
- log_fn(LOG_INFO,"Address sent for resolve, ap socket %d, n_circ_id %d",
- ap_conn->s, circ->n_circ_id);
- control_event_stream_status(ap_conn, STREAM_EVENT_SENT_RESOLVE);
- return 0;
- }
- /** Make an AP connection_t, do a socketpair 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 other end of the socketpair, or -1 if error.
- */
- int connection_ap_make_bridge(char *address, uint16_t port) {
- int fd[2];
- connection_t *conn;
- log_fn(LOG_INFO,"Making AP bridge to %s:%d ...",address,port);
- if (tor_socketpair(AF_UNIX, SOCK_STREAM, 0, fd) < 0) {
- log(LOG_WARN,"Couldn't construct socketpair (%s). Network down? Delaying.",
- tor_socket_strerror(tor_socket_errno(-1)));
- return -1;
- }
- set_socket_nonblocking(fd[0]);
- set_socket_nonblocking(fd[1]);
- conn = connection_new(CONN_TYPE_AP);
- conn->s = fd[0];
- /* 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->address = tor_strdup("(local bridge)");
- conn->addr = 0;
- conn->port = 0;
- if (connection_add(conn) < 0) { /* no space, forget it */
- connection_free(conn); /* this closes fd[0] */
- tor_close_socket(fd[1]);
- return -1;
- }
- conn->state = AP_CONN_STATE_CIRCUIT_WAIT;
- connection_start_reading(conn);
- /* attaching to a dirty circuit is fine */
- if (connection_ap_handshake_attach_circuit(conn) < 0) {
- connection_close_unattached_ap(conn, END_STREAM_REASON_CANT_ATTACH);
- tor_close_socket(fd[1]);
- return -1;
- }
- log_fn(LOG_INFO,"... AP bridge created and connected.");
- return fd[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) or
- * -1 for unreachable; the answer should be in the format specified
- * in the socks extensions document.
- **/
- void connection_ap_handshake_socks_resolved(connection_t *conn,
- int answer_type,
- size_t answer_len,
- const char *answer)
- {
- char buf[256];
- size_t replylen;
- if (answer_type == RESOLVED_TYPE_IPV4) {
- uint32_t a = get_uint32(answer);
- if (a)
- client_dns_set_addressmap(conn->socks_request->address, ntohl(a),
- conn->chosen_exit_name);
- }
- if (conn->socks_request->socks_version == 4) {
- buf[0] = 0x00; /* version */
- if (answer_type == RESOLVED_TYPE_IPV4 && answer_len == 4) {
- buf[1] = 90; /* "Granted" */
- set_uint16(buf+2, 0);
- memcpy(buf+4, answer, 4); /* address */
- replylen = SOCKS4_NETWORK_LEN;
- } else {
- buf[1] = 91; /* "error" */
- memset(buf+2, 0, 6);
- replylen = SOCKS4_NETWORK_LEN;
- }
- } else {
- /* 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 {
- buf[1] = SOCKS5_HOST_UNREACHABLE;
- memset(buf+2, 0, 8);
- replylen = 10;
- }
- }
- connection_ap_handshake_socks_reply(conn, buf, replylen,
- (answer_type == RESOLVED_TYPE_IPV4 ||
- answer_type == RESOLVED_TYPE_IPV6) ?
- SOCKS5_SUCCEEDED : SOCKS5_HOST_UNREACHABLE);
- }
- /** Send a socks reply to stream <b>conn</b>, using the appropriate
- * socks version, etc, and mark <b>conn</b> as completed with SOCKS
- * handshaking.
- *
- * If <b>reply</b> is defined, then write <b>replylen</b> bytes of it
- * to conn and return, else reply based on <b>status</b>.
- *
- * If <b>reply</b> is undefined, <b>status</b> can't be 0.
- */
- void connection_ap_handshake_socks_reply(connection_t *conn, char *reply,
- size_t replylen,
- socks5_reply_status_t status) {
- char buf[256];
- tor_assert(conn->socks_request); /* make sure it's an AP stream */
- control_event_stream_status(conn,
- status==SOCKS5_SUCCEEDED ? STREAM_EVENT_SUCCEEDED : STREAM_EVENT_FAILED);
- if (conn->socks_request->has_finished) {
- log_fn(LOG_WARN, "Harmless bug: duplicate calls to connection_ap_handshake_socks_reply.");
- return;
- }
- if (replylen) { /* we already have a reply in mind */
- connection_write_to_buf(reply, replylen, conn);
- conn->socks_request->has_finished = 1;
- return;
- }
- if (conn->socks_request->socks_version == 4) {
- memset(buf,0,SOCKS4_NETWORK_LEN);
- #define SOCKS4_GRANTED 90
- #define SOCKS4_REJECT 91
- buf[1] = (status==SOCKS5_SUCCEEDED ? SOCKS4_GRANTED : SOCKS4_REJECT);
- /* leave version, destport, destip zero */
- connection_write_to_buf(buf, SOCKS4_NETWORK_LEN, conn);
- } else if (conn->socks_request->socks_version == 5) {
- buf[0] = 5; /* version 5 */
- buf[1] = (char)status;
- buf[2] = 0;
- buf[3] = 1; /* ipv4 addr */
- memset(buf+4,0,6); /* Set external addr/port to 0.
- The spec doesn't seem to say what to do here. -RD */
- connection_write_to_buf(buf,10,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;
- }
- /** A relay 'begin' 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 -1 if we want to tear down <b>circ</b>. Else return 0.
- */
- int connection_exit_begin_conn(cell_t *cell, circuit_t *circ) {
- connection_t *n_stream;
- relay_header_t rh;
- char *address=NULL;
- uint16_t port;
- assert_circuit_ok(circ);
- relay_header_unpack(&rh, cell->payload);
- /* XXX currently we don't send an end cell back if we drop the
- * begin because it's malformed.
- */
- if (!memchr(cell->payload+RELAY_HEADER_SIZE, 0, rh.length)) {
- log_fn(LOG_WARN,"relay begin cell has no \\0. Dropping.");
- return 0;
- }
- if (parse_addr_port(cell->payload+RELAY_HEADER_SIZE,&address,NULL,&port)<0) {
- log_fn(LOG_WARN,"Unable to parse addr:port in relay begin cell. Dropping.");
- return 0;
- }
- if (port==0) {
- log_fn(LOG_WARN,"Missing port in relay begin cell. Dropping.");
- tor_free(address);
- return 0;
- }
- log_fn(LOG_DEBUG,"Creating new exit connection.");
- n_stream = connection_new(CONN_TYPE_EXIT);
- n_stream->purpose = EXIT_PURPOSE_CONNECT;
- n_stream->stream_id = rh.stream_id;
- n_stream->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) {
- log_fn(LOG_DEBUG,"begin is for rendezvous. configuring stream.");
- n_stream->address = tor_strdup("(rendezvous)");
- n_stream->state = EXIT_CONN_STATE_CONNECTING;
- strlcpy(n_stream->rend_query, circ->rend_query,
- sizeof(n_stream->rend_query));
- tor_assert(connection_edge_is_rendezvous_stream(n_stream));
- assert_circuit_ok(circ);
- if (rend_service_set_connection_addr_port(n_stream, circ) < 0) {
- log_fn(LOG_INFO,"Didn't find rendezvous service (port %d)",n_stream->port);
- connection_edge_end(n_stream, END_STREAM_REASON_EXITPOLICY, n_stream->cpath_layer);
- connection_free(n_stream);
- circuit_mark_for_close(circ); /* knock the whole thing down, somebody screwed up */
- tor_free(address);
- return 0;
- }
- assert_circuit_ok(circ);
- log_fn(LOG_DEBUG,"Finished assigning addr/port");
- n_stream->cpath_layer = circ->cpath->prev; /* link it */
- /* add it into the linked list of n_streams on this circuit */
- n_stream->next_stream = circ->n_streams;
- circ->n_streams = n_stream;
- assert_circuit_ok(circ);
- connection_exit_connect(n_stream);
- tor_free(address);
- return 0;
- }
- tor_strlower(address);
- n_stream->address = address;
- n_stream->state = EXIT_CONN_STATE_RESOLVEFAILED;
- /* default to failed, change in dns_resolve if it turns out not to fail */
- if (we_are_hibernating()) {
- connection_edge_end(n_stream, END_STREAM_REASON_HIBERNATING, n_stream->cpath_layer);
- connection_free(n_stream);
- return 0;
- }
- /* send it off to the gethostbyname farm */
- switch (dns_resolve(n_stream)) {
- case 1: /* resolve worked */
- /* add it into the linked list of n_streams on this circuit */
- n_stream->next_stream = circ->n_streams;
- circ->n_streams = n_stream;
- assert_circuit_ok(circ);
- connection_exit_connect(n_stream);
- return 0;
- case -1: /* resolve failed */
- /* n_stream got freed. don't touch it. */
- break;
- case 0: /* resolve added to pending list */
- /* add it into the linked list of resolving_streams on this circuit */
- n_stream->next_stream = circ->resolving_streams;
- circ->resolving_streams = n_stream;
- assert_circuit_ok(circ);
- ;
- }
- return 0;
- }
- /**
- * Called when we receive a RELAY_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, circuit_t *circ) {
- connection_t *dummy_conn;
- relay_header_t rh;
- assert_circuit_ok(circ);
- relay_header_unpack(&rh, cell->payload);
- /* 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 = connection_new(CONN_TYPE_EXIT);
- dummy_conn->stream_id = rh.stream_id;
- dummy_conn->address = tor_strndup(cell->payload+RELAY_HEADER_SIZE,
- rh.length);
- dummy_conn->port = 0;
- dummy_conn->state = EXIT_CONN_STATE_RESOLVEFAILED;
- dummy_conn->purpose = EXIT_PURPOSE_RESOLVE;
- /* 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->marked_for_close)
- connection_free(dummy_conn);
- return 0;
- case 0: /* resolve added to pending list */
- dummy_conn->next_stream = circ->resolving_streams;
- circ->resolving_streams = dummy_conn;
- assert_circuit_ok(circ);
- break;
- }
- 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 <em>only</em> if it's a general exit stream. (Rendezvous
- * streams must not reveal what IP they connected to.)
- */
- void
- connection_exit_connect(connection_t *conn) {
- unsigned char connected_payload[4];
- uint32_t addr;
- uint16_t port;
- if (!connection_edge_is_rendezvous_stream(conn) &&
- router_compare_to_my_exit_policy(conn) == ADDR_POLICY_REJECTED) {
- log_fn(LOG_INFO,"%s:%d failed exit policy. Closing.", conn->address, conn->port);
- connection_edge_end(conn, END_STREAM_REASON_EXITPOLICY, conn->cpath_layer);
- circuit_detach_stream(circuit_get_by_conn(conn), conn);
- connection_free(conn);
- return;
- }
- addr = conn->addr;
- port = conn->port;
- if (redirect_exit_list) {
- SMARTLIST_FOREACH(redirect_exit_list, exit_redirect_t *, r,
- {
- if ((addr&r->mask)==(r->addr&r->mask) &&
- (r->port_min <= port) && (port <= r->port_max)) {
- struct in_addr in;
- if (r->is_redirect) {
- char tmpbuf[INET_NTOA_BUF_LEN];
- addr = r->addr_dest;
- port = r->port_dest;
- in.s_addr = htonl(addr);
- tor_inet_ntoa(&in, tmpbuf, sizeof(tmpbuf));
- log_fn(LOG_DEBUG, "Redirecting connection from %s:%d to %s:%d",
- conn->address, conn->port, tmpbuf, port);
- }
- break;
- }
- });
- }
- log_fn(LOG_DEBUG,"about to try connecting");
- switch (connection_connect(conn, conn->address, addr, port)) {
- case -1:
- connection_edge_end_errno(conn, conn->cpath_layer);
- circuit_detach_stream(circuit_get_by_conn(conn), conn);
- connection_free(conn);
- return;
- case 0:
- conn->state = EXIT_CONN_STATE_CONNECTING;
- connection_watch_events(conn, EV_WRITE | EV_READ);
- /* writable indicates finish;
- * readable/error indicates broken link in windowsland. */
- return;
- /* case 1: fall through */
- }
- conn->state = EXIT_CONN_STATE_OPEN;
- if (connection_wants_to_flush(conn)) { /* in case there are any queued data cells */
- log_fn(LOG_WARN,"Bug: newly connected conn had data waiting!");
- // connection_start_writing(conn);
- }
- connection_watch_events(conn, EV_READ);
- /* also, deliver a 'connected' cell back through the circuit. */
- if (connection_edge_is_rendezvous_stream(conn)) { /* rendezvous stream */
- /* don't send an address back! */
- connection_edge_send_command(conn, circuit_get_by_conn(conn), RELAY_COMMAND_CONNECTED,
- NULL, 0, conn->cpath_layer);
- } else { /* normal stream */
- /* This must be the original address, not the redirected address. */
- *(uint32_t*)connected_payload = htonl(conn->addr);
- connection_edge_send_command(conn, circuit_get_by_conn(conn), RELAY_COMMAND_CONNECTED,
- connected_payload, 4, conn->cpath_layer);
- }
- }
- /** Return 1 if <b>conn</b> is a rendezvous stream, or 0 if
- * it is a general stream.
- */
- int connection_edge_is_rendezvous_stream(connection_t *conn) {
- tor_assert(conn);
- if (*conn->rend_query) /* XXX */
- return 1;
- return 0;
- }
- /** Return 1 if router <b>exit</b> is likely to allow stream <b>conn</b>
- * 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(connection_t *conn, routerinfo_t *exit)
- {
- tor_assert(conn);
- tor_assert(conn->type == CONN_TYPE_AP);
- tor_assert(conn->socks_request);
- tor_assert(exit);
- log_fn(LOG_DEBUG,"considering nickname %s, for address %s / port %d:",
- exit->nickname, conn->socks_request->address,
- conn->socks_request->port);
- /* 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) {
- if (router_get_by_nickname(conn->chosen_exit_name) != exit) {
- /* doesn't match */
- log_fn(LOG_DEBUG,"Requested node '%s', considering node '%s'. No.",
- conn->chosen_exit_name, exit->nickname);
- return 0;
- }
- }
- if (conn->socks_request->command != SOCKS_COMMAND_RESOLVE) {
- struct in_addr in;
- uint32_t addr = 0;
- addr_policy_result_t r;
- if (tor_inet_aton(conn->socks_request->address, &in))
- addr = ntohl(in.s_addr);
- r = router_compare_addr_to_addr_policy(addr, conn->socks_request->port,
- exit->exit_policy);
- if (r == ADDR_POLICY_REJECTED || r == ADDR_POLICY_PROBABLY_REJECTED)
- return 0;
- }
- return 1;
- }
- /** A helper function for socks_policy_permits_address() below.
- *
- * Parse options->SocksPolicy in the same way that the exit policy
- * is parsed, and put the processed version in &socks_policy.
- * Ignore port specifiers.
- */
- void
- parse_socks_policy(void)
- {
- addr_policy_t *n;
- if (socks_policy) {
- addr_policy_free(socks_policy);
- socks_policy = NULL;
- }
- config_parse_addr_policy(get_options()->SocksPolicy, &socks_policy);
- /* ports aren't used. */
- for (n=socks_policy; n; n = n->next) {
- n->prt_min = 1;
- n->prt_max = 65535;
- }
- }
- void
- free_socks_policy(void)
- {
- addr_policy_free(socks_policy);
- socks_policy = NULL;
- }
- /** Return 1 if <b>addr</b> is permitted to connect to our socks port,
- * based on <b>socks_policy</b>. Else return 0.
- */
- int socks_policy_permits_address(uint32_t addr)
- {
- int a;
- if (!socks_policy) /* 'no socks policy' means 'accept' */
- return 1;
- a = router_compare_addr_to_addr_policy(addr, 1, socks_policy);
- if (a==ADDR_POLICY_REJECTED)
- return 0;
- else if (a==ADDR_POLICY_ACCEPTED)
- return 1;
- log_fn(LOG_WARN, "Bug: Got unexpected 'maybe' answer from socks policy");
- return 0;
- }
- /** Make connection redirection follow the provided list of
- * exit_redirect_t */
- void
- set_exit_redirects(smartlist_t *lst)
- {
- if (redirect_exit_list) {
- SMARTLIST_FOREACH(redirect_exit_list, exit_redirect_t *, p, tor_free(p));
- smartlist_free(redirect_exit_list);
- }
- redirect_exit_list = lst;
- }
- /** If address is of the form "y.onion" with a well-formed handle y:
- * Put a '\0' after y, lower-case it, and return ONION_HOSTNAME.
- *
- * If address is of the form "y.exit":
- * Put a '\0' after y and return EXIT_HOSTNAME.
- *
- * Otherwise:
- * Return NORMAL_HOSTNAME and change nothing.
- */
- hostname_type_t
- parse_extended_hostname(char *address) {
- char *s;
- char query[REND_SERVICE_ID_LEN+1];
- s = strrchr(address,'.');
- if (!s) return 0; /* no dot, thus normal */
- if (!strcmp(s+1,"exit")) {
- *s = 0; /* null-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; /* null-terminate it */
- if (strlcpy(query, address, REND_SERVICE_ID_LEN+1) >= REND_SERVICE_ID_LEN+1)
- goto failed;
- if (rend_valid_service_id(query)) {
- return ONION_HOSTNAME; /* success */
- }
- failed:
- /* otherwise, return to previous state and return 0 */
- *s = '.';
- return NORMAL_HOSTNAME;
- }
|