1 /* Copyright (c) 2001 Matej Pfajfar.
2 * Copyright (c) 2001-2004, Roger Dingledine.
3 * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
4 * Copyright (c) 2007-2009, The Tor Project, Inc. */
5 /* See LICENSE for licensing information */
8 * \file connection_or.c
9 * \brief Functions to handle OR connections, TLS handshaking, and
10 * cells on the network.
15 static int connection_tls_finish_handshake(or_connection_t
*conn
);
16 static int connection_or_process_cells_from_inbuf(or_connection_t
*conn
);
17 static int connection_or_send_versions(or_connection_t
*conn
);
18 static int connection_init_or_handshake_state(or_connection_t
*conn
,
20 static int connection_or_check_valid_tls_handshake(or_connection_t
*conn
,
22 char *digest_rcvd_out
);
24 /**************************************************************/
26 /** Map from identity digest of connected OR or desired OR to a connection_t
27 * with that identity digest. If there is more than one such connection_t,
28 * they form a linked list, with next_with_same_id as the next pointer. */
29 static digestmap_t
*orconn_identity_map
= NULL
;
31 /** If conn is listed in orconn_identity_map, remove it, and clear
32 * conn->identity_digest. Otherwise do nothing. */
34 connection_or_remove_from_identity_map(or_connection_t
*conn
)
38 if (!orconn_identity_map
)
40 tmp
= digestmap_get(orconn_identity_map
, conn
->identity_digest
);
42 if (!tor_digest_is_zero(conn
->identity_digest
)) {
43 log_warn(LD_BUG
, "Didn't find connection '%s' on identity map when "
44 "trying to remove it.",
45 conn
->nickname
? conn
->nickname
: "NULL");
50 if (conn
->next_with_same_id
)
51 digestmap_set(orconn_identity_map
, conn
->identity_digest
,
52 conn
->next_with_same_id
);
54 digestmap_remove(orconn_identity_map
, conn
->identity_digest
);
56 while (tmp
->next_with_same_id
) {
57 if (tmp
->next_with_same_id
== conn
) {
58 tmp
->next_with_same_id
= conn
->next_with_same_id
;
61 tmp
= tmp
->next_with_same_id
;
64 memset(conn
->identity_digest
, 0, DIGEST_LEN
);
65 conn
->next_with_same_id
= NULL
;
68 /** Remove all entries from the identity-to-orconn map, and clear
69 * all identities in OR conns.*/
71 connection_or_clear_identity_map(void)
73 smartlist_t
*conns
= get_connection_array();
74 SMARTLIST_FOREACH(conns
, connection_t
*, conn
,
76 if (conn
->type
== CONN_TYPE_OR
) {
77 or_connection_t
*or_conn
= TO_OR_CONN(conn
);
78 memset(or_conn
->identity_digest
, 0, DIGEST_LEN
);
79 or_conn
->next_with_same_id
= NULL
;
83 digestmap_free(orconn_identity_map
, NULL
);
84 orconn_identity_map
= NULL
;
87 /** Change conn->identity_digest to digest, and add conn into
88 * orconn_digest_map. */
90 connection_or_set_identity_digest(or_connection_t
*conn
, const char *digest
)
96 if (!orconn_identity_map
)
97 orconn_identity_map
= digestmap_new();
98 if (!memcmp(conn
->identity_digest
, digest
, DIGEST_LEN
))
101 /* If the identity was set previously, remove the old mapping. */
102 if (! tor_digest_is_zero(conn
->identity_digest
))
103 connection_or_remove_from_identity_map(conn
);
105 memcpy(conn
->identity_digest
, digest
, DIGEST_LEN
);
107 /* If we're setting the ID to zero, don't add a mapping. */
108 if (tor_digest_is_zero(digest
))
111 tmp
= digestmap_set(orconn_identity_map
, digest
, conn
);
112 conn
->next_with_same_id
= tmp
;
115 /* Testing code to check for bugs in representation. */
116 for (; tmp
; tmp
= tmp
->next_with_same_id
) {
117 tor_assert(!memcmp(tmp
->identity_digest
, digest
, DIGEST_LEN
));
118 tor_assert(tmp
!= conn
);
123 /** Pack the cell_t host-order structure <b>src</b> into network-order
124 * in the buffer <b>dest</b>. See tor-spec.txt for details about the
127 * Note that this function doesn't touch <b>dst</b>-\>next: the caller
128 * should set it or clear it as appropriate.
131 cell_pack(packed_cell_t
*dst
, const cell_t
*src
)
133 char *dest
= dst
->body
;
134 *(uint16_t*)dest
= htons(src
->circ_id
);
135 *(uint8_t*)(dest
+2) = src
->command
;
136 memcpy(dest
+3, src
->payload
, CELL_PAYLOAD_SIZE
);
139 /** Unpack the network-order buffer <b>src</b> into a host-order
140 * cell_t structure <b>dest</b>.
143 cell_unpack(cell_t
*dest
, const char *src
)
145 dest
->circ_id
= ntohs(*(uint16_t*)(src
));
146 dest
->command
= *(uint8_t*)(src
+2);
147 memcpy(dest
->payload
, src
+3, CELL_PAYLOAD_SIZE
);
150 /** Write the header of <b>cell</b> into the first VAR_CELL_HEADER_SIZE
151 * bytes of <b>hdr_out</b>. */
153 var_cell_pack_header(const var_cell_t
*cell
, char *hdr_out
)
155 set_uint16(hdr_out
, htons(cell
->circ_id
));
156 set_uint8(hdr_out
+2, cell
->command
);
157 set_uint16(hdr_out
+3, htons(cell
->payload_len
));
160 /** Allocate and return a new var_cell_t with <b>payload_len</b> bytes of
163 var_cell_new(uint16_t payload_len
)
165 var_cell_t
*cell
= tor_malloc(sizeof(var_cell_t
)+payload_len
-1);
166 cell
->payload_len
= payload_len
;
172 /** Release all space held by <b>cell</b>. */
174 var_cell_free(var_cell_t
*cell
)
179 /** We've received an EOF from <b>conn</b>. Mark it for close and return. */
181 connection_or_reached_eof(or_connection_t
*conn
)
183 log_info(LD_OR
,"OR connection reached EOF. Closing.");
184 connection_mark_for_close(TO_CONN(conn
));
188 /** Handle any new bytes that have come in on connection <b>conn</b>.
189 * If conn is in 'open' state, hand it to
190 * connection_or_process_cells_from_inbuf()
194 connection_or_process_inbuf(or_connection_t
*conn
)
199 switch (conn
->_base
.state
) {
200 case OR_CONN_STATE_PROXY_HANDSHAKING
:
201 ret
= connection_read_proxy_handshake(TO_CONN(conn
));
203 /* start TLS after handshake completion, or deal with error */
205 tor_assert(TO_CONN(conn
)->proxy_state
== PROXY_CONNECTED
);
206 if (connection_tls_start_handshake(conn
, 0) < 0)
210 connection_mark_for_close(TO_CONN(conn
));
214 case OR_CONN_STATE_OPEN
:
215 case OR_CONN_STATE_OR_HANDSHAKING
:
216 return connection_or_process_cells_from_inbuf(conn
);
218 return 0; /* don't do anything */
222 /** When adding cells to an OR connection's outbuf, keep adding until the
223 * outbuf is at least this long, or we run out of cells. */
224 #define OR_CONN_HIGHWATER (32*1024)
226 /** Add cells to an OR connection's outbuf whenever the outbuf's data length
227 * drops below this size. */
228 #define OR_CONN_LOWWATER (16*1024)
230 /** Called whenever we have flushed some data on an or_conn: add more data
231 * from active circuits. */
233 connection_or_flushed_some(or_connection_t
*conn
)
235 size_t datalen
= buf_datalen(conn
->_base
.outbuf
);
236 /* If we're under the low water mark, add cells until we're just over the
237 * high water mark. */
238 if (datalen
< OR_CONN_LOWWATER
) {
239 ssize_t n
= (OR_CONN_HIGHWATER
- datalen
+ CELL_NETWORK_SIZE
-1)
241 time_t now
= approx_time();
242 while (conn
->active_circuits
&& n
> 0) {
244 flushed
= connection_or_flush_from_first_active_circuit(conn
, 1, now
);
251 /** Connection <b>conn</b> has finished writing and has no bytes left on
254 * Otherwise it's in state "open": stop writing and return.
256 * If <b>conn</b> is broken, mark it for close and return -1, else
260 connection_or_finished_flushing(or_connection_t
*conn
)
263 assert_connection_ok(TO_CONN(conn
),0);
265 switch (conn
->_base
.state
) {
266 case OR_CONN_STATE_PROXY_HANDSHAKING
:
267 case OR_CONN_STATE_OPEN
:
268 case OR_CONN_STATE_OR_HANDSHAKING
:
269 connection_stop_writing(TO_CONN(conn
));
272 log_err(LD_BUG
,"Called in unexpected state %d.", conn
->_base
.state
);
273 tor_fragile_assert();
279 /** Connected handler for OR connections: begin the TLS handshake.
282 connection_or_finished_connecting(or_connection_t
*or_conn
)
287 conn
= TO_CONN(or_conn
);
288 tor_assert(conn
->state
== OR_CONN_STATE_CONNECTING
);
290 log_debug(LD_HANDSHAKE
,"OR connect() to router at %s:%u finished.",
291 conn
->address
,conn
->port
);
292 control_event_bootstrap(BOOTSTRAP_STATUS_HANDSHAKE
, 0);
294 proxy_type
= PROXY_NONE
;
296 if (get_options()->HttpsProxy
)
297 proxy_type
= PROXY_CONNECT
;
298 else if (get_options()->Socks4Proxy
)
299 proxy_type
= PROXY_SOCKS4
;
300 else if (get_options()->Socks5Proxy
)
301 proxy_type
= PROXY_SOCKS5
;
303 if (proxy_type
!= PROXY_NONE
) {
304 /* start proxy handshake */
305 if (connection_proxy_connect(conn
, proxy_type
) < 0) {
306 connection_mark_for_close(conn
);
310 connection_start_reading(conn
);
311 conn
->state
= OR_CONN_STATE_PROXY_HANDSHAKING
;
315 if (connection_tls_start_handshake(or_conn
, 0) < 0) {
316 /* TLS handshaking error of some kind. */
317 connection_mark_for_close(conn
);
323 /** If we don't necessarily know the router we're connecting to, but we
324 * have an addr/port/id_digest, then fill in as much as we can. Start
325 * by checking to see if this describes a router we know. */
327 connection_or_init_conn_from_address(or_connection_t
*conn
,
328 const tor_addr_t
*addr
, uint16_t port
,
329 const char *id_digest
,
332 or_options_t
*options
= get_options();
333 routerinfo_t
*r
= router_get_by_digest(id_digest
);
334 conn
->bandwidthrate
= (int)options
->BandwidthRate
;
335 conn
->read_bucket
= conn
->bandwidthburst
= (int)options
->BandwidthBurst
;
336 connection_or_set_identity_digest(conn
, id_digest
);
338 conn
->_base
.port
= port
;
339 tor_addr_copy(&conn
->_base
.addr
, addr
);
340 tor_addr_copy(&conn
->real_addr
, addr
);
342 /* XXXX proposal 118 will make this more complex. */
343 if (tor_addr_eq_ipv4h(&conn
->_base
.addr
, r
->addr
))
344 conn
->is_canonical
= 1;
346 /* Override the addr/port, so our log messages will make sense.
347 * This is dangerous, since if we ever try looking up a conn by
348 * its actual addr/port, we won't remember. Careful! */
349 /* XXXX arma: this is stupid, and it's the reason we need real_addr
350 * to track is_canonical properly. What requires it? */
351 /* XXXX <arma> i believe the reason we did this, originally, is because
352 * we wanted to log what OR a connection was to, and if we logged the
353 * right IP address and port 56244, that wouldn't be as helpful. now we
354 * log the "right" port too, so we know if it's moria1 or moria2.
356 tor_addr_from_ipv4h(&conn
->_base
.addr
, r
->addr
);
357 conn
->_base
.port
= r
->or_port
;
359 conn
->nickname
= tor_strdup(r
->nickname
);
360 tor_free(conn
->_base
.address
);
361 conn
->_base
.address
= tor_strdup(r
->address
);
364 /* If we're an authoritative directory server, we may know a
365 * nickname for this router. */
366 n
= dirserv_get_nickname_by_digest(id_digest
);
368 conn
->nickname
= tor_strdup(n
);
370 conn
->nickname
= tor_malloc(HEX_DIGEST_LEN
+2);
371 conn
->nickname
[0] = '$';
372 base16_encode(conn
->nickname
+1, HEX_DIGEST_LEN
+1,
373 conn
->identity_digest
, DIGEST_LEN
);
375 tor_free(conn
->_base
.address
);
376 conn
->_base
.address
= tor_dup_addr(addr
);
380 /** Return true iff <b>a</b> is "better" than <b>b</b> for new circuits.
382 * A more canonical connection is always better than a less canonical
383 * connection. That aside, a connection is better if it has circuits and the
384 * other does not, or if it was created more recently.
386 * Requires that both input connections are open; not is_bad_for_new_circs,
387 * and not impossibly non-canonical.
389 * If </b>forgive_new_connections</b> is true, then we do not call
390 * <b>a</b>better than <b>b</b> simply because b has no circuits,
391 * unless b is also relatively old.
394 connection_or_is_better(time_t now
,
395 const or_connection_t
*a
,
396 const or_connection_t
*b
,
397 int forgive_new_connections
)
400 /** Do not definitively deprecate a new connection with no circuits on it
401 * until this much time has passed. */
402 #define NEW_CONN_GRACE_PERIOD (15*60)
404 if (b
->is_canonical
&& !a
->is_canonical
)
405 return 0; /* A canonical connection is better than a non-canonical
406 * one, no matter how new it is or which has circuits. */
408 newer
= b
->_base
.timestamp_created
< a
->_base
.timestamp_created
;
411 /* We prefer canonical connections regardless of newness. */
412 (!b
->is_canonical
&& a
->is_canonical
) ||
413 /* If both have circuits we prefer the newer: */
414 (b
->n_circuits
&& a
->n_circuits
&& newer
) ||
415 /* If neither has circuits we prefer the newer: */
416 (!b
->n_circuits
&& !a
->n_circuits
&& newer
))
419 /* If one has no circuits and the other does... */
420 if (!b
->n_circuits
&& a
->n_circuits
) {
421 /* Then it's bad, unless it's in its grace period and we're forgiving. */
422 if (forgive_new_connections
&&
423 now
< b
->_base
.timestamp_created
+ NEW_CONN_GRACE_PERIOD
)
432 /** Return the OR connection we should use to extend a circuit to the router
433 * whose identity is <b>digest</b>, and whose address we believe (or have been
434 * told in an extend cell) is <b>target_addr</b>. If there is no good
435 * connection, set *<b>msg_out</b> to a message describing the connection's
436 * state and our next action, and set <b>launch_out</b> to a boolean for
437 * whether we should launch a new connection or not.
440 connection_or_get_for_extend(const char *digest
,
441 const tor_addr_t
*target_addr
,
442 const char **msg_out
,
445 or_connection_t
*conn
, *best
=NULL
;
446 int n_inprogress_goodaddr
= 0, n_old
= 0, n_noncanonical
= 0, n_possible
= 0;
447 time_t now
= approx_time();
450 tor_assert(launch_out
);
452 if (!orconn_identity_map
) {
453 *msg_out
= "Router not connected (nothing is). Connecting.";
458 conn
= digestmap_get(orconn_identity_map
, digest
);
460 for (; conn
; conn
= conn
->next_with_same_id
) {
461 tor_assert(conn
->_base
.magic
== OR_CONNECTION_MAGIC
);
462 tor_assert(conn
->_base
.type
== CONN_TYPE_OR
);
463 tor_assert(!memcmp(conn
->identity_digest
, digest
, DIGEST_LEN
));
464 if (conn
->_base
.marked_for_close
)
466 /* Never return a non-open connection. */
467 if (conn
->_base
.state
!= OR_CONN_STATE_OPEN
) {
468 /* If the address matches, don't launch a new connection for this
470 if (!tor_addr_compare(&conn
->real_addr
, target_addr
, CMP_EXACT
))
471 ++n_inprogress_goodaddr
;
474 /* Never return a connection that shouldn't be used for circs. */
475 if (conn
->is_bad_for_new_circs
) {
479 /* Never return a non-canonical connection using a recent link protocol
480 * if the address is not what we wanted.
482 * (For old link protocols, we can't rely on is_canonical getting
483 * set properly if we're talking to the right address, since we might
484 * have an out-of-date descriptor, and we will get no NETINFO cell to
485 * tell us about the right address.) */
486 if (!conn
->is_canonical
&& conn
->link_proto
>= 2 &&
487 tor_addr_compare(&conn
->real_addr
, target_addr
, CMP_EXACT
)) {
495 best
= conn
; /* If we have no 'best' so far, this one is good enough. */
499 if (connection_or_is_better(now
, conn
, best
, 0))
504 *msg_out
= "Connection is fine; using it.";
507 } else if (n_inprogress_goodaddr
) {
508 *msg_out
= "Connection in progress; waiting.";
511 } else if (n_old
|| n_noncanonical
) {
512 *msg_out
= "Connections all too old, or too non-canonical. "
513 " Launching a new one.";
517 *msg_out
= "Not connected. Connecting.";
523 /** How old do we let a connection to an OR get before deciding it's
524 * too old for new circuits? */
525 #define TIME_BEFORE_OR_CONN_IS_TOO_OLD (60*60*24*7)
527 /** Given the head of the linked list for all the or_connections with a given
528 * identity, set elements of that list as is_bad_for_new_circs() as
529 * appropriate. Helper for connection_or_set_bad_connections().
532 connection_or_group_set_badness(or_connection_t
*head
)
534 or_connection_t
*or_conn
= NULL
, *best
= NULL
;
535 int n_old
= 0, n_inprogress
= 0, n_canonical
= 0, n_other
= 0;
536 time_t now
= time(NULL
);
538 /* Pass 1: expire everything that's old, and see what the status of
539 * everything else is. */
540 for (or_conn
= head
; or_conn
; or_conn
= or_conn
->next_with_same_id
) {
541 if (or_conn
->_base
.marked_for_close
||
542 or_conn
->is_bad_for_new_circs
)
544 if (or_conn
->_base
.timestamp_created
+ TIME_BEFORE_OR_CONN_IS_TOO_OLD
547 "Marking OR conn to %s:%d as too old for new circuits "
548 "(fd %d, %d secs old).",
549 or_conn
->_base
.address
, or_conn
->_base
.port
, or_conn
->_base
.s
,
550 (int)(now
- or_conn
->_base
.timestamp_created
));
551 or_conn
->is_bad_for_new_circs
= 1;
554 if (or_conn
->is_bad_for_new_circs
) {
556 } else if (or_conn
->_base
.state
!= OR_CONN_STATE_OPEN
) {
558 } else if (or_conn
->is_canonical
) {
565 /* Pass 2: We know how about how good the best connection is.
566 * expire everything that's worse, and find the very best if we can. */
567 for (or_conn
= head
; or_conn
; or_conn
= or_conn
->next_with_same_id
) {
568 if (or_conn
->_base
.marked_for_close
||
569 or_conn
->is_bad_for_new_circs
)
570 continue; /* This one doesn't need to be marked bad. */
571 if (or_conn
->_base
.state
!= OR_CONN_STATE_OPEN
)
572 continue; /* Don't mark anything bad until we have seen what happens
573 * when the connection finishes. */
574 if (n_canonical
&& !or_conn
->is_canonical
) {
575 /* We have at least one open canonical connection to this router,
576 * and this one is open but not canonical. Mark it bad. */
578 "Marking OR conn to %s:%d as too old for new circuits: "
579 "(fd %d, %d secs old). It is not canonical, and we have "
580 "another connection to that OR that is.",
581 or_conn
->_base
.address
, or_conn
->_base
.port
, or_conn
->_base
.s
,
582 (int)(now
- or_conn
->_base
.timestamp_created
));
583 or_conn
->is_bad_for_new_circs
= 1;
587 if (!best
|| connection_or_is_better(now
, or_conn
, best
, 0))
594 /* Pass 3: One connection to OR is best. If it's canonical, mark as bad
595 * every other open connection. If it's non-canonical, mark as bad
596 * every other open connection to the same address.
598 * XXXX This isn't optimal; if we have connections to an OR at multiple
599 * addresses, we'd like to pick the best _for each address_, and mark as
600 * bad every open connection that isn't best for its address. But this
601 * can only occur in cases where the other OR is old (so we have no
602 * canonical connection to it), or where all the connections to the OR are
603 * at noncanonical addresses and we have no good direct connection (which
604 * means we aren't at risk of attaching circuits to it anyway). As
605 * 0.1.2.x dies out, the first case will go away, and the second one is
606 * "mostly harmless", so a fix can wait until somebody is bored.
608 for (or_conn
= head
; or_conn
; or_conn
= or_conn
->next_with_same_id
) {
609 if (or_conn
->_base
.marked_for_close
||
610 or_conn
->is_bad_for_new_circs
||
611 or_conn
->_base
.state
!= OR_CONN_STATE_OPEN
)
613 if (or_conn
!= best
&& connection_or_is_better(now
, best
, or_conn
, 1)) {
614 /* This isn't the best conn, _and_ the best conn is better than it,
615 even when we're being forgiving. */
616 if (best
->is_canonical
) {
618 "Marking OR conn to %s:%d as too old for new circuits: "
619 "(fd %d, %d secs old). We have a better canonical one "
620 "(fd %d; %d secs old).",
621 or_conn
->_base
.address
, or_conn
->_base
.port
, or_conn
->_base
.s
,
622 (int)(now
- or_conn
->_base
.timestamp_created
),
623 best
->_base
.s
, (int)(now
- best
->_base
.timestamp_created
));
624 or_conn
->is_bad_for_new_circs
= 1;
625 } else if (!tor_addr_compare(&or_conn
->real_addr
,
626 &best
->real_addr
, CMP_EXACT
)) {
628 "Marking OR conn to %s:%d as too old for new circuits: "
629 "(fd %d, %d secs old). We have a better one "
630 "(fd %d; %d secs old).",
631 or_conn
->_base
.address
, or_conn
->_base
.port
, or_conn
->_base
.s
,
632 (int)(now
- or_conn
->_base
.timestamp_created
),
633 best
->_base
.s
, (int)(now
- best
->_base
.timestamp_created
));
634 or_conn
->is_bad_for_new_circs
= 1;
640 /** Go through all the OR connections, and set the is_bad_for_new_circs
642 * - all connections that are too old.
643 * - all open non-canonical connections for which a canonical connection
644 * exists to the same router.
645 * - all open canonical connections for which a 'better' canonical
646 * connection exists to the same router.
647 * - all open non-canonical connections for which a 'better' non-canonical
648 * connection exists to the same router at the same address.
650 * See connection_or_is_better() for our idea of what makes one OR connection
651 * better than another.
654 connection_or_set_bad_connections(void)
656 if (!orconn_identity_map
)
659 DIGESTMAP_FOREACH(orconn_identity_map
, identity
, or_connection_t
*, conn
) {
660 connection_or_group_set_badness(conn
);
661 } DIGESTMAP_FOREACH_END
;
664 /** <b>conn</b> is in the 'connecting' state, and it failed to complete
665 * a TCP connection. Send notifications appropriately.
667 * <b>reason</b> specifies the or_conn_end_reason for the failure;
668 * <b>msg</b> specifies the strerror-style error message.
671 connection_or_connect_failed(or_connection_t
*conn
,
672 int reason
, const char *msg
)
674 control_event_or_conn_status(conn
, OR_CONN_EVENT_FAILED
, reason
);
675 if (!authdir_mode_tests_reachability(get_options()))
676 control_event_bootstrap_problem(msg
, reason
);
679 /** Launch a new OR connection to <b>addr</b>:<b>port</b> and expect to
680 * handshake with an OR with identity digest <b>id_digest</b>.
682 * If <b>id_digest</b> is me, do nothing. If we're already connected to it,
683 * return that connection. If the connect() is in progress, set the
684 * new conn's state to 'connecting' and return it. If connect() succeeds,
685 * call connection_tls_start_handshake() on it.
687 * This function is called from router_retry_connections(), for
688 * ORs connecting to ORs, and circuit_establish_circuit(), for
689 * OPs connecting to ORs.
691 * Return the launched conn, or NULL if it failed.
694 connection_or_connect(const tor_addr_t
*_addr
, uint16_t port
,
695 const char *id_digest
)
697 or_connection_t
*conn
;
698 or_options_t
*options
= get_options();
699 int socket_error
= 0;
704 tor_assert(id_digest
);
705 tor_addr_copy(&addr
, _addr
);
707 if (server_mode(options
) && router_digest_is_me(id_digest
)) {
708 log_info(LD_PROTOCOL
,"Client asked me to connect to myself. Refusing.");
712 conn
= or_connection_new(AF_INET
);
714 /* set up conn so it's got all the data we need to remember */
715 connection_or_init_conn_from_address(conn
, &addr
, port
, id_digest
, 1);
716 conn
->_base
.state
= OR_CONN_STATE_CONNECTING
;
717 control_event_or_conn_status(conn
, OR_CONN_EVENT_LAUNCHED
, 0);
719 /* use a proxy server if available */
720 if (options
->HttpsProxy
) {
722 tor_addr_copy(&addr
, &options
->HttpsProxyAddr
);
723 port
= options
->HttpsProxyPort
;
724 } else if (options
->Socks4Proxy
) {
726 tor_addr_copy(&addr
, &options
->Socks4ProxyAddr
);
727 port
= options
->Socks4ProxyPort
;
728 } else if (options
->Socks5Proxy
) {
730 tor_addr_copy(&addr
, &options
->Socks5ProxyAddr
);
731 port
= options
->Socks5ProxyPort
;
734 switch (connection_connect(TO_CONN(conn
), conn
->_base
.address
,
735 &addr
, port
, &socket_error
)) {
737 /* If the connection failed immediately, and we're using
738 * a proxy, our proxy is down. Don't blame the Tor server. */
740 entry_guard_register_connect_status(conn
->identity_digest
,
742 connection_or_connect_failed(conn
,
743 errno_to_orconn_end_reason(socket_error
),
744 tor_socket_strerror(socket_error
));
745 connection_free(TO_CONN(conn
));
748 connection_watch_events(TO_CONN(conn
), READ_EVENT
| WRITE_EVENT
);
749 /* writable indicates finish, readable indicates broken link,
750 error indicates broken link on windows */
752 /* case 1: fall through */
755 if (connection_or_finished_connecting(conn
) < 0) {
756 /* already marked for close */
762 /** Begin the tls handshake with <b>conn</b>. <b>receiving</b> is 0 if
763 * we initiated the connection, else it's 1.
765 * Assign a new tls object to conn->tls, begin reading on <b>conn</b>, and
766 * pass <b>conn</b> to connection_tls_continue_handshake().
768 * Return -1 if <b>conn</b> is broken, else return 0.
771 connection_tls_start_handshake(or_connection_t
*conn
, int receiving
)
773 conn
->_base
.state
= OR_CONN_STATE_TLS_HANDSHAKING
;
774 conn
->tls
= tor_tls_new(conn
->_base
.s
, receiving
);
775 tor_tls_set_logged_address(conn
->tls
, // XXX client and relay?
776 escaped_safe_str(conn
->_base
.address
));
778 log_warn(LD_BUG
,"tor_tls_new failed. Closing.");
781 connection_start_reading(TO_CONN(conn
));
782 log_debug(LD_HANDSHAKE
,"starting TLS handshake on fd %d", conn
->_base
.s
);
783 note_crypto_pk_op(receiving
? TLS_HANDSHAKE_S
: TLS_HANDSHAKE_C
);
785 if (connection_tls_continue_handshake(conn
) < 0) {
791 /** Invoked on the server side from inside tor_tls_read() when the server
792 * gets a successful TLS renegotiation from the client. */
794 connection_or_tls_renegotiated_cb(tor_tls_t
*tls
, void *_conn
)
796 or_connection_t
*conn
= _conn
;
799 /* Don't invoke this again. */
800 tor_tls_set_renegotiate_callback(tls
, NULL
, NULL
);
801 tor_tls_block_renegotiation(tls
);
803 if (connection_tls_finish_handshake(conn
) < 0) {
804 /* XXXX_TLS double-check that it's ok to do this from inside read. */
805 /* XXXX_TLS double-check that this verifies certificates. */
806 connection_mark_for_close(TO_CONN(conn
));
810 /** Move forward with the tls handshake. If it finishes, hand
811 * <b>conn</b> to connection_tls_finish_handshake().
813 * Return -1 if <b>conn</b> is broken, else return 0.
816 connection_tls_continue_handshake(or_connection_t
*conn
)
819 check_no_tls_errors();
821 if (conn
->_base
.state
== OR_CONN_STATE_TLS_CLIENT_RENEGOTIATING
) {
822 // log_notice(LD_OR, "Renegotiate with %p", conn->tls);
823 result
= tor_tls_renegotiate(conn
->tls
);
824 // log_notice(LD_OR, "Result: %d", result);
826 tor_assert(conn
->_base
.state
== OR_CONN_STATE_TLS_HANDSHAKING
);
827 // log_notice(LD_OR, "Continue handshake with %p", conn->tls);
828 result
= tor_tls_handshake(conn
->tls
);
829 // log_notice(LD_OR, "Result: %d", result);
832 CASE_TOR_TLS_ERROR_ANY
:
833 log_info(LD_OR
,"tls error [%s]. breaking connection.",
834 tor_tls_err_to_string(result
));
837 if (! tor_tls_used_v1_handshake(conn
->tls
)) {
838 if (!tor_tls_is_server(conn
->tls
)) {
839 if (conn
->_base
.state
== OR_CONN_STATE_TLS_HANDSHAKING
) {
840 // log_notice(LD_OR,"Done. state was TLS_HANDSHAKING.");
841 conn
->_base
.state
= OR_CONN_STATE_TLS_CLIENT_RENEGOTIATING
;
844 // log_notice(LD_OR,"Done. state was %d.", conn->_base.state);
846 /* improved handshake, but not a client. */
847 tor_tls_set_renegotiate_callback(conn
->tls
,
848 connection_or_tls_renegotiated_cb
,
850 conn
->_base
.state
= OR_CONN_STATE_TLS_SERVER_RENEGOTIATING
;
851 connection_stop_writing(TO_CONN(conn
));
852 connection_start_reading(TO_CONN(conn
));
856 return connection_tls_finish_handshake(conn
);
857 case TOR_TLS_WANTWRITE
:
858 connection_start_writing(TO_CONN(conn
));
859 log_debug(LD_OR
,"wanted write");
861 case TOR_TLS_WANTREAD
: /* handshaking conns are *always* reading */
862 log_debug(LD_OR
,"wanted read");
865 log_info(LD_OR
,"tls closed. breaking connection.");
871 /** Return 1 if we initiated this connection, or 0 if it started
872 * out as an incoming connection.
875 connection_or_nonopen_was_started_here(or_connection_t
*conn
)
877 tor_assert(conn
->_base
.type
== CONN_TYPE_OR
);
879 return 1; /* it's still in proxy states or something */
880 if (conn
->handshake_state
)
881 return conn
->handshake_state
->started_here
;
882 return !tor_tls_is_server(conn
->tls
);
885 /** <b>Conn</b> just completed its handshake. Return 0 if all is well, and
886 * return -1 if he is lying, broken, or otherwise something is wrong.
888 * If we initiated this connection (<b>started_here</b> is true), make sure
889 * the other side sent sent a correctly formed certificate. If I initiated the
890 * connection, make sure it's the right guy.
892 * Otherwise (if we _didn't_ initiate this connection), it's okay for
893 * the certificate to be weird or absent.
895 * If we return 0, and the certificate is as expected, write a hash of the
896 * identity key into digest_rcvd, which must have DIGEST_LEN space in it. (If
897 * we return -1 this buffer is undefined.) If the certificate is invalid
898 * or missing on an incoming connection, we return 0 and set digest_rcvd to
899 * DIGEST_LEN 0 bytes.
902 * 1) Set conn->circ_id_type according to tor-spec.txt.
903 * 2) If we're an authdirserver and we initiated the connection: drop all
904 * descriptors that claim to be on that IP/port but that aren't
905 * this guy; and note that this guy is reachable.
908 connection_or_check_valid_tls_handshake(or_connection_t
*conn
,
910 char *digest_rcvd_out
)
912 crypto_pk_env_t
*identity_rcvd
=NULL
;
913 or_options_t
*options
= get_options();
914 int severity
= server_mode(options
) ? LOG_PROTOCOL_WARN
: LOG_WARN
;
915 const char *safe_address
=
916 started_here
? conn
->_base
.address
:
917 safe_str_client(conn
->_base
.address
);
918 const char *conn_type
= started_here
? "outgoing" : "incoming";
919 int has_cert
= 0, has_identity
=0;
921 check_no_tls_errors();
922 has_cert
= tor_tls_peer_has_cert(conn
->tls
);
923 if (started_here
&& !has_cert
) {
924 log_info(LD_HANDSHAKE
,"Tried connecting to router at %s:%d, but it didn't "
925 "send a cert! Closing.",
926 safe_address
, conn
->_base
.port
);
928 } else if (!has_cert
) {
929 log_debug(LD_HANDSHAKE
,"Got incoming connection with no certificate. "
932 check_no_tls_errors();
935 int v
= tor_tls_verify(started_here
?severity
:LOG_INFO
,
936 conn
->tls
, &identity_rcvd
);
937 if (started_here
&& v
<0) {
938 log_fn(severity
,LD_HANDSHAKE
,"Tried connecting to router at %s:%d: It"
939 " has a cert but it's invalid. Closing.",
940 safe_address
, conn
->_base
.port
);
943 log_info(LD_HANDSHAKE
,"Incoming connection gave us an invalid cert "
946 log_debug(LD_HANDSHAKE
,
947 "The certificate seems to be valid on %s connection "
948 "with %s:%d", conn_type
, safe_address
, conn
->_base
.port
);
950 check_no_tls_errors();
955 crypto_pk_get_digest(identity_rcvd
, digest_rcvd_out
);
956 if (crypto_pk_cmp_keys(get_identity_key(), identity_rcvd
)<0) {
957 conn
->circ_id_type
= CIRC_ID_TYPE_LOWER
;
959 conn
->circ_id_type
= CIRC_ID_TYPE_HIGHER
;
961 crypto_free_pk_env(identity_rcvd
);
963 memset(digest_rcvd_out
, 0, DIGEST_LEN
);
964 conn
->circ_id_type
= CIRC_ID_TYPE_NEITHER
;
967 if (started_here
&& tor_digest_is_zero(conn
->identity_digest
)) {
968 connection_or_set_identity_digest(conn
, digest_rcvd_out
);
969 tor_free(conn
->nickname
);
970 conn
->nickname
= tor_malloc(HEX_DIGEST_LEN
+2);
971 conn
->nickname
[0] = '$';
972 base16_encode(conn
->nickname
+1, HEX_DIGEST_LEN
+1,
973 conn
->identity_digest
, DIGEST_LEN
);
974 log_info(LD_HANDSHAKE
, "Connected to router %s at %s:%d without knowing "
975 "its key. Hoping for the best.",
976 conn
->nickname
, conn
->_base
.address
, conn
->_base
.port
);
980 int as_advertised
= 1;
981 tor_assert(has_cert
);
982 tor_assert(has_identity
);
983 if (memcmp(digest_rcvd_out
, conn
->identity_digest
, DIGEST_LEN
)) {
984 /* I was aiming for a particular digest. I didn't get it! */
985 char seen
[HEX_DIGEST_LEN
+1];
986 char expected
[HEX_DIGEST_LEN
+1];
987 base16_encode(seen
, sizeof(seen
), digest_rcvd_out
, DIGEST_LEN
);
988 base16_encode(expected
, sizeof(expected
), conn
->identity_digest
,
990 log_fn(severity
, LD_HANDSHAKE
,
991 "Tried connecting to router at %s:%d, but identity key was not "
992 "as expected: wanted %s but got %s.",
993 conn
->_base
.address
, conn
->_base
.port
, expected
, seen
);
994 entry_guard_register_connect_status(conn
->identity_digest
, 0, 1,
996 control_event_or_conn_status(conn
, OR_CONN_EVENT_FAILED
,
997 END_OR_CONN_REASON_OR_IDENTITY
);
998 if (!authdir_mode_tests_reachability(options
))
999 control_event_bootstrap_problem("foo", END_OR_CONN_REASON_OR_IDENTITY
);
1002 if (authdir_mode_tests_reachability(options
)) {
1003 /* We initiated this connection to address:port. Drop all routers
1004 * with the same address:port and a different key.
1006 dirserv_orconn_tls_done(conn
->_base
.address
, conn
->_base
.port
,
1007 digest_rcvd_out
, as_advertised
);
1015 /** The tls handshake is finished.
1017 * Make sure we are happy with the person we just handshaked with.
1019 * If he initiated the connection, make sure he's not already connected,
1020 * then initialize conn from the information in router.
1022 * If all is successful, call circuit_n_conn_done() to handle events
1023 * that have been pending on the <tls handshake completion. Also set the
1024 * directory to be dirty (only matters if I'm an authdirserver).
1027 connection_tls_finish_handshake(or_connection_t
*conn
)
1029 char digest_rcvd
[DIGEST_LEN
];
1030 int started_here
= connection_or_nonopen_was_started_here(conn
);
1032 log_debug(LD_HANDSHAKE
,"tls handshake with %s done. verifying.",
1033 safe_str_client(conn
->_base
.address
));
1035 directory_set_dirty();
1037 if (connection_or_check_valid_tls_handshake(conn
, started_here
,
1041 circuit_build_times_network_is_live(&circ_times
);
1043 if (tor_tls_used_v1_handshake(conn
->tls
)) {
1044 conn
->link_proto
= 1;
1045 if (!started_here
) {
1046 connection_or_init_conn_from_address(conn
, &conn
->_base
.addr
,
1047 conn
->_base
.port
, digest_rcvd
, 0);
1049 tor_tls_block_renegotiation(conn
->tls
);
1050 return connection_or_set_state_open(conn
);
1052 conn
->_base
.state
= OR_CONN_STATE_OR_HANDSHAKING
;
1053 if (connection_init_or_handshake_state(conn
, started_here
) < 0)
1055 if (!started_here
) {
1056 connection_or_init_conn_from_address(conn
, &conn
->_base
.addr
,
1057 conn
->_base
.port
, digest_rcvd
, 0);
1059 return connection_or_send_versions(conn
);
1063 /** Allocate a new connection handshake state for the connection
1064 * <b>conn</b>. Return 0 on success, -1 on failure. */
1066 connection_init_or_handshake_state(or_connection_t
*conn
, int started_here
)
1068 or_handshake_state_t
*s
;
1069 s
= conn
->handshake_state
= tor_malloc_zero(sizeof(or_handshake_state_t
));
1070 s
->started_here
= started_here
? 1 : 0;
1074 /** Free all storage held by <b>state</b>. */
1076 or_handshake_state_free(or_handshake_state_t
*state
)
1080 memset(state
, 0xBE, sizeof(or_handshake_state_t
));
1084 /** Set <b>conn</b>'s state to OR_CONN_STATE_OPEN, and tell other subsystems
1085 * as appropriate. Called when we are done with all TLS and OR handshaking.
1088 connection_or_set_state_open(or_connection_t
*conn
)
1090 int started_here
= connection_or_nonopen_was_started_here(conn
);
1091 time_t now
= time(NULL
);
1092 conn
->_base
.state
= OR_CONN_STATE_OPEN
;
1093 control_event_or_conn_status(conn
, OR_CONN_EVENT_CONNECTED
, 0);
1096 circuit_build_times_network_is_live(&circ_times
);
1097 rep_hist_note_connect_succeeded(conn
->identity_digest
, now
);
1098 if (entry_guard_register_connect_status(conn
->identity_digest
,
1100 /* Close any circuits pending on this conn. We leave it in state
1101 * 'open' though, because it didn't actually *fail* -- we just
1102 * chose not to use it. (Otherwise
1103 * connection_about_to_close_connection() will call a big pile of
1104 * functions to indicate we shouldn't try it again.) */
1105 log_debug(LD_OR
, "New entry guard was reachable, but closing this "
1106 "connection so we can retry the earlier entry guards.");
1107 circuit_n_conn_done(conn
, 0);
1110 router_set_status(conn
->identity_digest
, 1);
1112 /* only report it to the geoip module if it's not a known router */
1113 if (!router_get_by_digest(conn
->identity_digest
)) {
1114 if (tor_addr_family(&TO_CONN(conn
)->addr
) == AF_INET
) {
1115 /*XXXX IP6 support ipv6 geoip.*/
1116 uint32_t a
= tor_addr_to_ipv4h(&TO_CONN(conn
)->addr
);
1117 geoip_note_client_seen(GEOIP_CLIENT_CONNECT
, a
, now
);
1122 or_handshake_state_free(conn
->handshake_state
);
1123 conn
->handshake_state
= NULL
;
1125 connection_start_reading(TO_CONN(conn
));
1126 circuit_n_conn_done(conn
, 1); /* send the pending creates, if any. */
1131 /** Pack <b>cell</b> into wire-format, and write it onto <b>conn</b>'s outbuf.
1132 * For cells that use or affect a circuit, this should only be called by
1133 * connection_or_flush_from_first_active_circuit().
1136 connection_or_write_cell_to_buf(const cell_t
*cell
, or_connection_t
*conn
)
1138 packed_cell_t networkcell
;
1143 cell_pack(&networkcell
, cell
);
1145 connection_write_to_buf(networkcell
.body
, CELL_NETWORK_SIZE
, TO_CONN(conn
));
1147 if (cell
->command
!= CELL_PADDING
)
1148 conn
->timestamp_last_added_nonpadding
= approx_time();
1151 /** Pack a variable-length <b>cell</b> into wire-format, and write it onto
1152 * <b>conn</b>'s outbuf. Right now, this <em>DOES NOT</em> support cells that
1156 connection_or_write_var_cell_to_buf(const var_cell_t
*cell
,
1157 or_connection_t
*conn
)
1159 char hdr
[VAR_CELL_HEADER_SIZE
];
1162 var_cell_pack_header(cell
, hdr
);
1163 connection_write_to_buf(hdr
, sizeof(hdr
), TO_CONN(conn
));
1164 connection_write_to_buf(cell
->payload
, cell
->payload_len
, TO_CONN(conn
));
1165 if (cell
->command
!= CELL_PADDING
)
1166 conn
->timestamp_last_added_nonpadding
= approx_time();
1169 /** See whether there's a variable-length cell waiting on <b>conn</b>'s
1170 * inbuf. Return values as for fetch_var_cell_from_buf(). */
1172 connection_fetch_var_cell_from_buf(or_connection_t
*conn
, var_cell_t
**out
)
1174 return fetch_var_cell_from_buf(conn
->_base
.inbuf
, out
, conn
->link_proto
);
1177 /** Process cells from <b>conn</b>'s inbuf.
1179 * Loop: while inbuf contains a cell, pull it off the inbuf, unpack it,
1180 * and hand it to command_process_cell().
1185 connection_or_process_cells_from_inbuf(or_connection_t
*conn
)
1187 var_cell_t
*var_cell
;
1191 "%d: starting, inbuf_datalen %d (%d pending in tls object).",
1192 conn
->_base
.s
,(int)buf_datalen(conn
->_base
.inbuf
),
1193 tor_tls_get_pending_bytes(conn
->tls
));
1194 if (connection_fetch_var_cell_from_buf(conn
, &var_cell
)) {
1196 return 0; /* not yet. */
1197 circuit_build_times_network_is_live(&circ_times
);
1198 command_process_var_cell(var_cell
, conn
);
1199 var_cell_free(var_cell
);
1201 char buf
[CELL_NETWORK_SIZE
];
1203 if (buf_datalen(conn
->_base
.inbuf
) < CELL_NETWORK_SIZE
) /* whole response
1205 return 0; /* not yet */
1207 circuit_build_times_network_is_live(&circ_times
);
1208 connection_fetch_from_buf(buf
, CELL_NETWORK_SIZE
, TO_CONN(conn
));
1210 /* retrieve cell info from buf (create the host-order struct from the
1211 * network-order string) */
1212 cell_unpack(&cell
, buf
);
1214 command_process_cell(&cell
, conn
);
1219 /** Write a destroy cell with circ ID <b>circ_id</b> and reason <b>reason</b>
1220 * onto OR connection <b>conn</b>. Don't perform range-checking on reason:
1221 * we may want to propagate reasons from other cells.
1226 connection_or_send_destroy(circid_t circ_id
, or_connection_t
*conn
, int reason
)
1232 memset(&cell
, 0, sizeof(cell_t
));
1233 cell
.circ_id
= circ_id
;
1234 cell
.command
= CELL_DESTROY
;
1235 cell
.payload
[0] = (uint8_t) reason
;
1236 log_debug(LD_OR
,"Sending destroy (circID %d).", circ_id
);
1238 /* XXXX It's possible that under some circumstances, we want the destroy
1239 * to take precedence over other data waiting on the circuit's cell queue.
1242 connection_or_write_cell_to_buf(&cell
, conn
);
1246 /** Array of recognized link protocol versions. */
1247 static const uint16_t or_protocol_versions
[] = { 1, 2 };
1248 /** Number of versions in <b>or_protocol_versions</b>. */
1249 static const int n_or_protocol_versions
=
1250 (int)( sizeof(or_protocol_versions
)/sizeof(uint16_t) );
1252 /** Return true iff <b>v</b> is a link protocol version that this Tor
1253 * implementation believes it can support. */
1255 is_or_protocol_version_known(uint16_t v
)
1258 for (i
= 0; i
< n_or_protocol_versions
; ++i
) {
1259 if (or_protocol_versions
[i
] == v
)
1265 /** Send a VERSIONS cell on <b>conn</b>, telling the other host about the
1266 * link protocol versions that this Tor can support. */
1268 connection_or_send_versions(or_connection_t
*conn
)
1272 tor_assert(conn
->handshake_state
&&
1273 !conn
->handshake_state
->sent_versions_at
);
1274 cell
= var_cell_new(n_or_protocol_versions
* 2);
1275 cell
->command
= CELL_VERSIONS
;
1276 for (i
= 0; i
< n_or_protocol_versions
; ++i
) {
1277 uint16_t v
= or_protocol_versions
[i
];
1278 set_uint16(cell
->payload
+(2*i
), htons(v
));
1281 connection_or_write_var_cell_to_buf(cell
, conn
);
1282 conn
->handshake_state
->sent_versions_at
= time(NULL
);
1284 var_cell_free(cell
);
1288 /** Send a NETINFO cell on <b>conn</b>, telling the other server what we know
1289 * about their address, our address, and the current time. */
1291 connection_or_send_netinfo(or_connection_t
*conn
)
1294 time_t now
= time(NULL
);
1299 memset(&cell
, 0, sizeof(cell_t
));
1300 cell
.command
= CELL_NETINFO
;
1303 set_uint32(cell
.payload
, htonl((uint32_t)now
));
1305 /* Their address. */
1306 out
= cell
.payload
+ 4;
1307 len
= append_address_to_payload(out
, &conn
->_base
.addr
);
1313 if ((me
= router_get_my_routerinfo())) {
1315 *out
++ = 1; /* only one address is supported. */
1317 tor_addr_from_ipv4h(&my_addr
, me
->addr
);
1318 len
= append_address_to_payload(out
, &my_addr
);
1326 connection_or_write_cell_to_buf(&cell
, conn
);