1 /* Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
2 * Copyright (c) 2007-2009, The Tor Project, Inc. */
3 /* See LICENSE for licensing information */
7 * \brief Client code to access location-hidden services.
12 /** Called when we've established a circuit to an introduction point:
13 * send the introduction request. */
15 rend_client_introcirc_has_opened(origin_circuit_t
*circ
)
17 tor_assert(circ
->_base
.purpose
== CIRCUIT_PURPOSE_C_INTRODUCING
);
18 tor_assert(circ
->cpath
);
20 log_info(LD_REND
,"introcirc is open");
21 connection_ap_attach_pending();
24 /** Send the establish-rendezvous cell along a rendezvous circuit. if
25 * it fails, mark the circ for close and return -1. else return 0.
28 rend_client_send_establish_rendezvous(origin_circuit_t
*circ
)
30 tor_assert(circ
->_base
.purpose
== CIRCUIT_PURPOSE_C_ESTABLISH_REND
);
31 tor_assert(circ
->rend_data
);
32 log_info(LD_REND
, "Sending an ESTABLISH_RENDEZVOUS cell");
34 if (crypto_rand(circ
->rend_data
->rend_cookie
, REND_COOKIE_LEN
) < 0) {
35 log_warn(LD_BUG
, "Internal error: Couldn't produce random cookie.");
36 circuit_mark_for_close(TO_CIRCUIT(circ
), END_CIRC_REASON_INTERNAL
);
39 if (relay_send_command_from_edge(0, TO_CIRCUIT(circ
),
40 RELAY_COMMAND_ESTABLISH_RENDEZVOUS
,
41 circ
->rend_data
->rend_cookie
,
43 circ
->cpath
->prev
)<0) {
44 /* circ is already marked for close */
45 log_warn(LD_GENERAL
, "Couldn't send ESTABLISH_RENDEZVOUS cell");
52 /** Called when we're trying to connect an ap conn; sends an INTRODUCE1 cell
53 * down introcirc if possible.
56 rend_client_send_introduction(origin_circuit_t
*introcirc
,
57 origin_circuit_t
*rendcirc
)
61 char payload
[RELAY_PAYLOAD_SIZE
];
62 char tmp
[RELAY_PAYLOAD_SIZE
];
63 rend_cache_entry_t
*entry
;
66 crypto_pk_env_t
*intro_key
; /* either Bob's public key or an intro key. */
68 tor_assert(introcirc
->_base
.purpose
== CIRCUIT_PURPOSE_C_INTRODUCING
);
69 tor_assert(rendcirc
->_base
.purpose
== CIRCUIT_PURPOSE_C_REND_READY
);
70 tor_assert(introcirc
->rend_data
);
71 tor_assert(rendcirc
->rend_data
);
72 tor_assert(!rend_cmp_service_ids(introcirc
->rend_data
->onion_address
,
73 rendcirc
->rend_data
->onion_address
));
75 if (rend_cache_lookup_entry(introcirc
->rend_data
->onion_address
, -1,
78 "query %s didn't have valid rend desc in cache. Failing.",
79 escaped_safe_str(introcirc
->rend_data
->onion_address
));
83 /* first 20 bytes of payload are the hash of Bob's pk */
84 if (entry
->parsed
->version
== 0) { /* un-versioned descriptor */
85 intro_key
= entry
->parsed
->pk
;
86 } else { /* versioned descriptor */
88 SMARTLIST_FOREACH(entry
->parsed
->intro_nodes
, rend_intro_point_t
*,
90 if (!memcmp(introcirc
->build_state
->chosen_exit
->identity_digest
,
91 intro
->extend_info
->identity_digest
, DIGEST_LEN
)) {
92 intro_key
= intro
->intro_key
;
97 /** XXX This case probably means that the intro point vanished while
98 * we were building a circuit to it. In the future, we should find
99 * out how that happened and whether we should kill the circuits to
100 * removed intro points immediately. See task 1073. */
101 int num_intro_points
= smartlist_len(entry
->parsed
->intro_nodes
);
102 if (rend_cache_lookup_entry(introcirc
->rend_data
->onion_address
,
104 log_info(LD_REND
, "We have both a v0 and a v2 rend desc for this "
105 "service. The v2 desc doesn't contain the introduction "
106 "point (and key) to send an INTRODUCE1/2 cell to this "
107 "introduction point. Assuming the introduction point "
108 "is for v0 rend clients and using the service key "
109 "from the v0 desc instead. (This is probably a bug, "
110 "because we shouldn't even have both a v0 and a v2 "
111 "descriptor for the same service.)");
112 /* See flyspray task 1024. */
113 intro_key
= entry
->parsed
->pk
;
115 log_info(LD_REND
, "Internal error: could not find intro key; we "
116 "only have a v2 rend desc with %d intro points.",
122 if (crypto_pk_get_digest(intro_key
, payload
)<0) {
123 log_warn(LD_BUG
, "Internal error: couldn't hash public key.");
127 /* Initialize the pending_final_cpath and start the DH handshake. */
128 cpath
= rendcirc
->build_state
->pending_final_cpath
;
130 cpath
= rendcirc
->build_state
->pending_final_cpath
=
131 tor_malloc_zero(sizeof(crypt_path_t
));
132 cpath
->magic
= CRYPT_PATH_MAGIC
;
133 if (!(cpath
->dh_handshake_state
= crypto_dh_new())) {
134 log_warn(LD_BUG
, "Internal error: couldn't allocate DH.");
137 if (crypto_dh_generate_public(cpath
->dh_handshake_state
)<0) {
138 log_warn(LD_BUG
, "Internal error: couldn't generate g^x.");
143 /* If version is 3, write (optional) auth data and timestamp. */
144 if (entry
->parsed
->protocols
& (1<<3)) {
145 tmp
[0] = 3; /* version 3 of the cell format */
146 tmp
[1] = (uint8_t)introcirc
->rend_data
->auth_type
; /* auth type, if any */
148 if (introcirc
->rend_data
->auth_type
!= REND_NO_AUTH
) {
149 set_uint16(tmp
+2, htons(REND_DESC_COOKIE_LEN
));
150 memcpy(tmp
+4, introcirc
->rend_data
->descriptor_cookie
,
151 REND_DESC_COOKIE_LEN
);
152 v3_shift
+= 2+REND_DESC_COOKIE_LEN
;
154 set_uint32(tmp
+v3_shift
+1, htonl((uint32_t)time(NULL
)));
156 } /* if version 2 only write version number */
157 else if (entry
->parsed
->protocols
& (1<<2)) {
158 tmp
[0] = 2; /* version 2 of the cell format */
161 /* write the remaining items into tmp */
162 if (entry
->parsed
->protocols
& (1<<3) || entry
->parsed
->protocols
& (1<<2)) {
163 /* version 2 format */
164 extend_info_t
*extend_info
= rendcirc
->build_state
->chosen_exit
;
167 set_uint32(tmp
+v3_shift
+1, tor_addr_to_ipv4h(&extend_info
->addr
));
168 set_uint16(tmp
+v3_shift
+5, htons(extend_info
->port
));
169 memcpy(tmp
+v3_shift
+7, extend_info
->identity_digest
, DIGEST_LEN
);
170 klen
= crypto_pk_asn1_encode(extend_info
->onion_key
,
171 tmp
+v3_shift
+7+DIGEST_LEN
+2,
172 sizeof(tmp
)-(v3_shift
+7+DIGEST_LEN
+2));
173 set_uint16(tmp
+v3_shift
+7+DIGEST_LEN
, htons(klen
));
174 memcpy(tmp
+v3_shift
+7+DIGEST_LEN
+2+klen
, rendcirc
->rend_data
->rend_cookie
,
176 dh_offset
= v3_shift
+7+DIGEST_LEN
+2+klen
+REND_COOKIE_LEN
;
179 strncpy(tmp
, rendcirc
->build_state
->chosen_exit
->nickname
,
180 (MAX_NICKNAME_LEN
+1)); /* nul pads */
181 memcpy(tmp
+MAX_NICKNAME_LEN
+1, rendcirc
->rend_data
->rend_cookie
,
183 dh_offset
= MAX_NICKNAME_LEN
+1+REND_COOKIE_LEN
;
186 if (crypto_dh_get_public(cpath
->dh_handshake_state
, tmp
+dh_offset
,
188 log_warn(LD_BUG
, "Internal error: couldn't extract g^x.");
192 note_crypto_pk_op(REND_CLIENT
);
193 /*XXX maybe give crypto_pk_public_hybrid_encrypt a max_len arg,
194 * to avoid buffer overflows? */
195 r
= crypto_pk_public_hybrid_encrypt(intro_key
, payload
+DIGEST_LEN
,
197 (int)(dh_offset
+DH_KEY_LEN
),
198 PK_PKCS1_OAEP_PADDING
, 0);
200 log_warn(LD_BUG
,"Internal error: hybrid pk encrypt failed.");
204 payload_len
= DIGEST_LEN
+ r
;
205 tor_assert(payload_len
<= RELAY_PAYLOAD_SIZE
); /* we overran something */
207 log_info(LD_REND
, "Sending an INTRODUCE1 cell");
208 if (relay_send_command_from_edge(0, TO_CIRCUIT(introcirc
),
209 RELAY_COMMAND_INTRODUCE1
,
210 payload
, payload_len
,
211 introcirc
->cpath
->prev
)<0) {
212 /* introcirc is already marked for close. leave rendcirc alone. */
213 log_warn(LD_BUG
, "Couldn't send INTRODUCE1 cell");
217 /* Now, we wait for an ACK or NAK on this circuit. */
218 introcirc
->_base
.purpose
= CIRCUIT_PURPOSE_C_INTRODUCE_ACK_WAIT
;
222 circuit_mark_for_close(TO_CIRCUIT(introcirc
), END_CIRC_REASON_INTERNAL
);
223 circuit_mark_for_close(TO_CIRCUIT(rendcirc
), END_CIRC_REASON_INTERNAL
);
227 /** Called when a rendezvous circuit is open; sends a establish
228 * rendezvous circuit as appropriate. */
230 rend_client_rendcirc_has_opened(origin_circuit_t
*circ
)
232 tor_assert(circ
->_base
.purpose
== CIRCUIT_PURPOSE_C_ESTABLISH_REND
);
234 log_info(LD_REND
,"rendcirc is open");
236 /* generate a rendezvous cookie, store it in circ */
237 if (rend_client_send_establish_rendezvous(circ
) < 0) {
242 /** Called when get an ACK or a NAK for a REND_INTRODUCE1 cell.
245 rend_client_introduction_acked(origin_circuit_t
*circ
,
246 const char *request
, size_t request_len
)
248 origin_circuit_t
*rendcirc
;
249 (void) request
; // XXXX Use this.
251 if (circ
->_base
.purpose
!= CIRCUIT_PURPOSE_C_INTRODUCE_ACK_WAIT
) {
252 log_warn(LD_PROTOCOL
,
253 "Received REND_INTRODUCE_ACK on unexpected circuit %d.",
254 circ
->_base
.n_circ_id
);
255 circuit_mark_for_close(TO_CIRCUIT(circ
), END_CIRC_REASON_TORPROTOCOL
);
259 tor_assert(circ
->build_state
->chosen_exit
);
260 tor_assert(circ
->rend_data
);
262 if (request_len
== 0) {
263 /* It's an ACK; the introduction point relayed our introduction request. */
264 /* Locate the rend circ which is waiting to hear about this ack,
267 log_info(LD_REND
,"Received ack. Telling rend circ...");
268 rendcirc
= circuit_get_by_rend_query_and_purpose(
269 circ
->rend_data
->onion_address
, CIRCUIT_PURPOSE_C_REND_READY
);
270 if (rendcirc
) { /* remember the ack */
271 rendcirc
->_base
.purpose
= CIRCUIT_PURPOSE_C_REND_READY_INTRO_ACKED
;
273 log_info(LD_REND
,"...Found no rend circ. Dropping on the floor.");
275 /* close the circuit: we won't need it anymore. */
276 circ
->_base
.purpose
= CIRCUIT_PURPOSE_C_INTRODUCE_ACKED
;
277 circuit_mark_for_close(TO_CIRCUIT(circ
), END_CIRC_REASON_FINISHED
);
279 /* It's a NAK; the introduction point didn't relay our request. */
280 circ
->_base
.purpose
= CIRCUIT_PURPOSE_C_INTRODUCING
;
281 /* Remove this intro point from the set of viable introduction
282 * points. If any remain, extend to a new one and try again.
283 * If none remain, refetch the service descriptor.
285 if (rend_client_remove_intro_point(circ
->build_state
->chosen_exit
,
286 circ
->rend_data
) > 0) {
287 /* There are introduction points left. Re-extend the circuit to
288 * another intro point and try again. */
289 extend_info_t
*extend_info
;
291 extend_info
= rend_client_get_random_intro(circ
->rend_data
);
293 log_warn(LD_REND
, "No introduction points left for %s. Closing.",
294 escaped_safe_str(circ
->rend_data
->onion_address
));
295 circuit_mark_for_close(TO_CIRCUIT(circ
), END_CIRC_REASON_INTERNAL
);
298 if (circ
->remaining_relay_early_cells
) {
300 "Got nack for %s from %s. Re-extending circ %d, "
302 escaped_safe_str(circ
->rend_data
->onion_address
),
303 circ
->build_state
->chosen_exit
->nickname
,
304 circ
->_base
.n_circ_id
, extend_info
->nickname
);
305 result
= circuit_extend_to_new_exit(circ
, extend_info
);
308 "Got nack for %s from %s. Building a new introduction "
309 "circuit, this time to %s.",
310 escaped_safe_str(circ
->rend_data
->onion_address
),
311 circ
->build_state
->chosen_exit
->nickname
,
312 extend_info
->nickname
);
313 circuit_mark_for_close(TO_CIRCUIT(circ
), END_CIRC_REASON_FINISHED
);
314 if (!circuit_launch_by_extend_info(CIRCUIT_PURPOSE_C_INTRODUCING
,
316 CIRCLAUNCH_IS_INTERNAL
)) {
317 log_warn(LD_REND
, "Building introduction circuit failed.");
323 extend_info_free(extend_info
);
330 /** The period for which a hidden service directory cannot be queried for
331 * the same descriptor ID again. */
332 #define REND_HID_SERV_DIR_REQUERY_PERIOD (15 * 60)
334 /** Contains the last request times to hidden service directories for
335 * certain queries; keys are strings consisting of base32-encoded
336 * hidden service directory identities and base32-encoded descriptor IDs;
337 * values are pointers to timestamps of the last requests. */
338 static strmap_t
*last_hid_serv_requests
= NULL
;
340 /** Look up the last request time to hidden service directory <b>hs_dir</b>
341 * for descriptor ID <b>desc_id_base32</b>. If <b>set</b> is non-zero,
342 * assign the current time <b>now</b> and return that. Otherwise, return
343 * the most recent request time, or 0 if no such request has been sent
346 lookup_last_hid_serv_request(routerstatus_t
*hs_dir
,
347 const char *desc_id_base32
, time_t now
, int set
)
349 char hsdir_id_base32
[REND_DESC_ID_V2_LEN_BASE32
+ 1];
350 char hsdir_desc_comb_id
[2 * REND_DESC_ID_V2_LEN_BASE32
+ 1];
351 time_t *last_request_ptr
;
352 base32_encode(hsdir_id_base32
, sizeof(hsdir_id_base32
),
353 hs_dir
->identity_digest
, DIGEST_LEN
);
354 tor_snprintf(hsdir_desc_comb_id
, sizeof(hsdir_desc_comb_id
), "%s%s",
355 hsdir_id_base32
, desc_id_base32
);
357 last_request_ptr
= tor_malloc_zero(sizeof(time_t *));
358 *last_request_ptr
= now
;
359 strmap_set(last_hid_serv_requests
, hsdir_desc_comb_id
, last_request_ptr
);
361 last_request_ptr
= strmap_get_lc(last_hid_serv_requests
,
363 return (last_request_ptr
) ? *last_request_ptr
: 0;
366 /** Clean the history of request times to hidden service directories, so that
367 * it does not contain requests older than REND_HID_SERV_DIR_REQUERY_PERIOD
368 * seconds any more. */
370 directory_clean_last_hid_serv_requests(void)
373 time_t cutoff
= time(NULL
) - REND_HID_SERV_DIR_REQUERY_PERIOD
;
374 if (!last_hid_serv_requests
)
375 last_hid_serv_requests
= strmap_new();
376 for (iter
= strmap_iter_init(last_hid_serv_requests
);
377 !strmap_iter_done(iter
); ) {
381 strmap_iter_get(iter
, &key
, &val
);
382 ent
= (time_t *) val
;
384 iter
= strmap_iter_next_rmv(last_hid_serv_requests
, iter
);
387 iter
= strmap_iter_next(last_hid_serv_requests
, iter
);
392 /** Determine the responsible hidden service directories for <b>desc_id</b>
393 * and fetch the descriptor belonging to that ID from one of them. Only
394 * send a request to hidden service directories that we did not try within
395 * the last REND_HID_SERV_DIR_REQUERY_PERIOD seconds; on success, return 1,
396 * in the case that no hidden service directory is left to ask for the
397 * descriptor, return 0, and in case of a failure -1. <b>query</b> is only
398 * passed for pretty log statements. */
400 directory_get_from_hs_dir(const char *desc_id
, const rend_data_t
*rend_query
)
402 smartlist_t
*responsible_dirs
= smartlist_create();
403 routerstatus_t
*hs_dir
;
404 char desc_id_base32
[REND_DESC_ID_V2_LEN_BASE32
+ 1];
405 time_t now
= time(NULL
);
406 char descriptor_cookie_base64
[3*REND_DESC_COOKIE_LEN_BASE64
];
408 tor_assert(rend_query
);
409 /* Determine responsible dirs. Even if we can't get all we want,
410 * work with the ones we have. If it's empty, we'll notice below. */
411 (int) hid_serv_get_responsible_directories(responsible_dirs
, desc_id
);
413 base32_encode(desc_id_base32
, sizeof(desc_id_base32
),
414 desc_id
, DIGEST_LEN
);
416 /* Only select those hidden service directories to which we did not send
417 * a request recently and for which we have a router descriptor here. */
418 directory_clean_last_hid_serv_requests(); /* Clean request history first. */
420 SMARTLIST_FOREACH(responsible_dirs
, routerstatus_t
*, dir
, {
421 if (lookup_last_hid_serv_request(dir
, desc_id_base32
, 0, 0) +
422 REND_HID_SERV_DIR_REQUERY_PERIOD
>= now
||
423 !router_get_by_digest(dir
->identity_digest
))
424 SMARTLIST_DEL_CURRENT(responsible_dirs
, dir
);
427 hs_dir
= smartlist_choose(responsible_dirs
);
428 smartlist_free(responsible_dirs
);
430 log_info(LD_REND
, "Could not pick one of the responsible hidden "
431 "service directories, because we requested them all "
432 "recently without success.");
436 /* Remember, that we are requesting a descriptor from this hidden service
438 lookup_last_hid_serv_request(hs_dir
, desc_id_base32
, now
, 1);
440 /* Encode descriptor cookie for logging purposes. */
441 if (rend_query
->auth_type
!= REND_NO_AUTH
) {
442 if (base64_encode(descriptor_cookie_base64
,
443 sizeof(descriptor_cookie_base64
),
444 rend_query
->descriptor_cookie
, REND_DESC_COOKIE_LEN
)<0) {
445 log_warn(LD_BUG
, "Could not base64-encode descriptor cookie.");
448 /* Remove == signs and newline. */
449 descriptor_cookie_base64
[strlen(descriptor_cookie_base64
)-3] = '\0';
451 strlcpy(descriptor_cookie_base64
, "(none)",
452 sizeof(descriptor_cookie_base64
));
455 /* Send fetch request. (Pass query and possibly descriptor cookie so that
456 * they can be written to the directory connection and be referred to when
457 * the response arrives. */
458 directory_initiate_command_routerstatus_rend(hs_dir
,
459 DIR_PURPOSE_FETCH_RENDDESC_V2
,
460 ROUTER_PURPOSE_GENERAL
,
461 1, desc_id_base32
, NULL
, 0, 0,
463 log_info(LD_REND
, "Sending fetch request for v2 descriptor for "
464 "service '%s' with descriptor ID '%s', auth type %d, "
465 "and descriptor cookie '%s' to hidden service "
466 "directory '%s' on port %d.",
467 rend_query
->onion_address
, desc_id_base32
,
468 rend_query
->auth_type
,
469 (rend_query
->auth_type
== REND_NO_AUTH
? "[none]" :
470 escaped_safe_str(descriptor_cookie_base64
)),
471 hs_dir
->nickname
, hs_dir
->dir_port
);
475 /** If we are not currently fetching a rendezvous service descriptor
476 * for the service ID <b>query</b>, start a directory connection to fetch a
480 rend_client_refetch_renddesc(const char *query
)
482 if (!get_options()->FetchHidServDescriptors
)
484 log_info(LD_REND
, "Fetching rendezvous descriptor for service %s",
485 escaped_safe_str(query
));
486 if (connection_get_by_type_state_rendquery(CONN_TYPE_DIR
, 0, query
, 0)) {
487 log_info(LD_REND
,"Would fetch a new renddesc here (for %s), but one is "
488 "already in progress.", escaped_safe_str(query
));
490 /* not one already; initiate a dir rend desc lookup */
491 directory_get_from_dirserver(DIR_PURPOSE_FETCH_RENDDESC
,
492 ROUTER_PURPOSE_GENERAL
, query
,
493 PDS_RETRY_IF_NO_SERVERS
);
497 /** Start a connection to a hidden service directory to fetch a v2
498 * rendezvous service descriptor for the base32-encoded service ID
502 rend_client_refetch_v2_renddesc(const rend_data_t
*rend_query
)
504 char descriptor_id
[DIGEST_LEN
];
505 int replicas_left_to_try
[REND_NUMBER_OF_NON_CONSECUTIVE_REPLICAS
];
506 int i
, tries_left
, r
;
507 rend_cache_entry_t
*e
= NULL
;
508 time_t now
= time(NULL
);
509 tor_assert(rend_query
);
510 /* Are we configured to fetch descriptors? */
511 if (!get_options()->FetchHidServDescriptors
) {
512 log_warn(LD_REND
, "We received an onion address for a v2 rendezvous "
513 "service descriptor, but are not fetching service descriptors.");
516 /* Before fetching, check if we already have the descriptor here. */
517 r
= rend_cache_lookup_entry(rend_query
->onion_address
, -1, &e
);
518 if (r
> 0 && now
- e
->received
< NUM_SECONDS_BEFORE_HS_REFETCH
) {
519 log_info(LD_REND
, "We would fetch a v2 rendezvous descriptor, but we "
520 "already have a fresh copy of that descriptor here. "
524 log_debug(LD_REND
, "Fetching v2 rendezvous descriptor for service %s",
525 safe_str(rend_query
->onion_address
));
526 /* Randomly iterate over the replicas until a descriptor can be fetched
527 * from one of the consecutive nodes, or no options are left. */
528 tries_left
= REND_NUMBER_OF_NON_CONSECUTIVE_REPLICAS
;
529 for (i
= 0; i
< REND_NUMBER_OF_NON_CONSECUTIVE_REPLICAS
; i
++)
530 replicas_left_to_try
[i
] = i
;
531 while (tries_left
> 0) {
532 int rand
= crypto_rand_int(tries_left
);
533 int chosen_replica
= replicas_left_to_try
[rand
];
534 replicas_left_to_try
[rand
] = replicas_left_to_try
[--tries_left
];
536 if (rend_compute_v2_desc_id(descriptor_id
, rend_query
->onion_address
,
537 rend_query
->auth_type
== REND_STEALTH_AUTH
?
538 rend_query
->descriptor_cookie
: NULL
,
539 time(NULL
), chosen_replica
) < 0) {
540 log_warn(LD_REND
, "Internal error: Computing v2 rendezvous "
541 "descriptor ID did not succeed.");
544 if (directory_get_from_hs_dir(descriptor_id
, rend_query
) != 0)
545 return; /* either success or failure, but we're done */
547 /* If we come here, there are no hidden service directories left. */
548 log_info(LD_REND
, "Could not pick one of the responsible hidden "
549 "service directories to fetch descriptors, because "
550 "we already tried them all unsuccessfully.");
551 /* Close pending connections (unless a v0 request is still going on). */
552 rend_client_desc_trynow(rend_query
->onion_address
, 2);
556 /** Remove failed_intro from ent. If ent now has no intro points, or
557 * service is unrecognized, then launch a new renddesc fetch.
559 * Return -1 if error, 0 if no intro points remain or service
560 * unrecognized, 1 if recognized and some intro points remain.
563 rend_client_remove_intro_point(extend_info_t
*failed_intro
,
564 const rend_data_t
*rend_query
)
567 rend_cache_entry_t
*ent
;
570 r
= rend_cache_lookup_entry(rend_query
->onion_address
, -1, &ent
);
572 log_warn(LD_BUG
, "Malformed service ID %s.",
573 escaped_safe_str(rend_query
->onion_address
));
577 log_info(LD_REND
, "Unknown service %s. Re-fetching descriptor.",
578 escaped_safe_str(rend_query
->onion_address
));
579 /* Fetch both, v0 and v2 rend descriptors in parallel. Use whichever
580 * arrives first. Exception: When using client authorization, only
581 * fetch v2 descriptors.*/
582 rend_client_refetch_v2_renddesc(rend_query
);
583 if (rend_query
->auth_type
== REND_NO_AUTH
)
584 rend_client_refetch_renddesc(rend_query
->onion_address
);
588 for (i
= 0; i
< smartlist_len(ent
->parsed
->intro_nodes
); i
++) {
589 rend_intro_point_t
*intro
= smartlist_get(ent
->parsed
->intro_nodes
, i
);
590 if (!memcmp(failed_intro
->identity_digest
,
591 intro
->extend_info
->identity_digest
, DIGEST_LEN
)) {
592 rend_intro_point_free(intro
);
593 smartlist_del(ent
->parsed
->intro_nodes
, i
);
598 if (smartlist_len(ent
->parsed
->intro_nodes
) == 0) {
600 "No more intro points remain for %s. Re-fetching descriptor.",
601 escaped_safe_str(rend_query
->onion_address
));
602 /* Fetch both, v0 and v2 rend descriptors in parallel. Use whichever
603 * arrives first. Exception: When using client authorization, only
604 * fetch v2 descriptors.*/
605 rend_client_refetch_v2_renddesc(rend_query
);
606 if (rend_query
->auth_type
== REND_NO_AUTH
)
607 rend_client_refetch_renddesc(rend_query
->onion_address
);
609 /* move all pending streams back to renddesc_wait */
610 while ((conn
= connection_get_by_type_state_rendquery(CONN_TYPE_AP
,
611 AP_CONN_STATE_CIRCUIT_WAIT
,
612 rend_query
->onion_address
, -1))) {
613 conn
->state
= AP_CONN_STATE_RENDDESC_WAIT
;
618 log_info(LD_REND
,"%d options left for %s.",
619 smartlist_len(ent
->parsed
->intro_nodes
),
620 escaped_safe_str(rend_query
->onion_address
));
624 /** Called when we receive a RENDEZVOUS_ESTABLISHED cell; changes the state of
625 * the circuit to C_REND_READY.
628 rend_client_rendezvous_acked(origin_circuit_t
*circ
, const char *request
,
633 /* we just got an ack for our establish-rendezvous. switch purposes. */
634 if (circ
->_base
.purpose
!= CIRCUIT_PURPOSE_C_ESTABLISH_REND
) {
635 log_warn(LD_PROTOCOL
,"Got a rendezvous ack when we weren't expecting one. "
637 circuit_mark_for_close(TO_CIRCUIT(circ
), END_CIRC_REASON_TORPROTOCOL
);
640 log_info(LD_REND
,"Got rendezvous ack. This circuit is now ready for "
642 circ
->_base
.purpose
= CIRCUIT_PURPOSE_C_REND_READY
;
643 /* XXXX022 This is a pretty brute-force approach. It'd be better to
644 * attach only the connections that are waiting on this circuit, rather
645 * than trying to attach them all. See comments bug 743. */
646 /* If we already have the introduction circuit built, make sure we send
647 * the INTRODUCE cell _now_ */
648 connection_ap_attach_pending();
652 /** Bob sent us a rendezvous cell; join the circuits. */
654 rend_client_receive_rendezvous(origin_circuit_t
*circ
, const char *request
,
658 char keys
[DIGEST_LEN
+CPATH_KEY_MATERIAL_LEN
];
660 if ((circ
->_base
.purpose
!= CIRCUIT_PURPOSE_C_REND_READY
&&
661 circ
->_base
.purpose
!= CIRCUIT_PURPOSE_C_REND_READY_INTRO_ACKED
)
662 || !circ
->build_state
->pending_final_cpath
) {
663 log_warn(LD_PROTOCOL
,"Got rendezvous2 cell from hidden service, but not "
664 "expecting it. Closing.");
665 circuit_mark_for_close(TO_CIRCUIT(circ
), END_CIRC_REASON_TORPROTOCOL
);
669 if (request_len
!= DH_KEY_LEN
+DIGEST_LEN
) {
670 log_warn(LD_PROTOCOL
,"Incorrect length (%d) on RENDEZVOUS2 cell.",
675 log_info(LD_REND
,"Got RENDEZVOUS2 cell from hidden service.");
677 /* first DH_KEY_LEN bytes are g^y from bob. Finish the dh handshake...*/
678 tor_assert(circ
->build_state
);
679 tor_assert(circ
->build_state
->pending_final_cpath
);
680 hop
= circ
->build_state
->pending_final_cpath
;
681 tor_assert(hop
->dh_handshake_state
);
682 if (crypto_dh_compute_secret(hop
->dh_handshake_state
, request
, DH_KEY_LEN
,
683 keys
, DIGEST_LEN
+CPATH_KEY_MATERIAL_LEN
)<0) {
684 log_warn(LD_GENERAL
, "Couldn't complete DH handshake.");
687 /* ... and set up cpath. */
688 if (circuit_init_cpath_crypto(hop
, keys
+DIGEST_LEN
, 0)<0)
691 /* Check whether the digest is right... */
692 if (memcmp(keys
, request
+DH_KEY_LEN
, DIGEST_LEN
)) {
693 log_warn(LD_PROTOCOL
, "Incorrect digest of key material.");
697 crypto_dh_free(hop
->dh_handshake_state
);
698 hop
->dh_handshake_state
= NULL
;
700 /* All is well. Extend the circuit. */
701 circ
->_base
.purpose
= CIRCUIT_PURPOSE_C_REND_JOINED
;
702 hop
->state
= CPATH_STATE_OPEN
;
703 /* set the windows to default. these are the windows
704 * that alice thinks bob has.
706 hop
->package_window
= CIRCWINDOW_START
;
707 hop
->deliver_window
= CIRCWINDOW_START
;
709 onion_append_to_cpath(&circ
->cpath
, hop
);
710 circ
->build_state
->pending_final_cpath
= NULL
; /* prevent double-free */
711 /* XXXX022 This is a pretty brute-force approach. It'd be better to
712 * attach only the connections that are waiting on this circuit, rather
713 * than trying to attach them all. See comments bug 743. */
714 connection_ap_attach_pending();
717 circuit_mark_for_close(TO_CIRCUIT(circ
), END_CIRC_REASON_TORPROTOCOL
);
721 /** Find all the apconns in state AP_CONN_STATE_RENDDESC_WAIT that
722 * are waiting on query. If there's a working cache entry here
723 * with at least one intro point, move them to the next state. If
724 * <b>rend_version</b> is non-negative, fail connections that have
725 * requested <b>query</b> unless there are still descriptor fetch
726 * requests in progress for other descriptor versions than
727 * <b>rend_version</b>.
730 rend_client_desc_trynow(const char *query
, int rend_version
)
732 edge_connection_t
*conn
;
733 rend_cache_entry_t
*entry
;
734 time_t now
= time(NULL
);
736 smartlist_t
*conns
= get_connection_array();
737 SMARTLIST_FOREACH(conns
, connection_t
*, _conn
,
739 if (_conn
->type
!= CONN_TYPE_AP
||
740 _conn
->state
!= AP_CONN_STATE_RENDDESC_WAIT
||
741 _conn
->marked_for_close
)
743 conn
= TO_EDGE_CONN(_conn
);
744 if (!conn
->rend_data
)
746 if (rend_cmp_service_ids(query
, conn
->rend_data
->onion_address
))
748 assert_connection_ok(TO_CONN(conn
), now
);
749 if (rend_cache_lookup_entry(conn
->rend_data
->onion_address
, -1,
751 smartlist_len(entry
->parsed
->intro_nodes
) > 0) {
752 /* either this fetch worked, or it failed but there was a
753 * valid entry from before which we should reuse */
754 log_info(LD_REND
,"Rend desc is usable. Launching circuits.");
755 conn
->_base
.state
= AP_CONN_STATE_CIRCUIT_WAIT
;
757 /* restart their timeout values, so they get a fair shake at
758 * connecting to the hidden service. */
759 conn
->_base
.timestamp_created
= now
;
760 conn
->_base
.timestamp_lastread
= now
;
761 conn
->_base
.timestamp_lastwritten
= now
;
763 if (connection_ap_handshake_attach_circuit(conn
) < 0) {
764 /* it will never work */
765 log_warn(LD_REND
,"Rendezvous attempt failed. Closing.");
766 if (!conn
->_base
.marked_for_close
)
767 connection_mark_unattached_ap(conn
, END_STREAM_REASON_CANT_ATTACH
);
769 } else { /* 404, or fetch didn't get that far */
770 /* Unless there are requests for another descriptor version pending,
771 * close the connection. */
772 if (rend_version
>= 0 &&
773 !connection_get_by_type_state_rendquery(CONN_TYPE_DIR
, 0, query
,
774 rend_version
== 0 ? 2 : 0)) {
775 log_notice(LD_REND
,"Closing stream for '%s.onion': hidden service is "
776 "unavailable (try again later).", safe_str(query
));
777 connection_mark_unattached_ap(conn
, END_STREAM_REASON_RESOLVEFAILED
);
783 /** Return a newly allocated extend_info_t* for a randomly chosen introduction
784 * point for the named hidden service. Return NULL if all introduction points
785 * have been tried and failed.
788 rend_client_get_random_intro(const rend_data_t
*rend_query
)
791 rend_cache_entry_t
*entry
;
792 rend_intro_point_t
*intro
;
793 routerinfo_t
*router
;
795 if (rend_cache_lookup_entry(rend_query
->onion_address
, -1, &entry
) < 1) {
797 "Query '%s' didn't have valid rend desc in cache. Failing.",
798 safe_str(rend_query
->onion_address
));
803 if (smartlist_len(entry
->parsed
->intro_nodes
) == 0)
806 i
= crypto_rand_int(smartlist_len(entry
->parsed
->intro_nodes
));
807 intro
= smartlist_get(entry
->parsed
->intro_nodes
, i
);
808 /* Do we need to look up the router or is the extend info complete? */
809 if (!intro
->extend_info
->onion_key
) {
810 router
= router_get_by_nickname(intro
->extend_info
->nickname
, 0);
812 log_info(LD_REND
, "Unknown router with nickname '%s'; trying another.",
813 intro
->extend_info
->nickname
);
814 rend_intro_point_free(intro
);
815 smartlist_del(entry
->parsed
->intro_nodes
, i
);
818 extend_info_free(intro
->extend_info
);
819 intro
->extend_info
= extend_info_from_router(router
);
821 return extend_info_dup(intro
->extend_info
);
824 /** Client-side authorizations for hidden services; map of onion address to
825 * rend_service_authorization_t*. */
826 static strmap_t
*auth_hid_servs
= NULL
;
828 /** Look up the client-side authorization for the hidden service with
829 * <b>onion_address</b>. Return NULL if no authorization is available for
831 rend_service_authorization_t
*
832 rend_client_lookup_service_authorization(const char *onion_address
)
834 tor_assert(onion_address
);
835 if (!auth_hid_servs
) return NULL
;
836 return strmap_get(auth_hid_servs
, onion_address
);
839 /** Helper: Free storage held by rend_service_authorization_t. */
841 rend_service_authorization_free(rend_service_authorization_t
*auth
)
846 /** Helper for strmap_free. */
848 rend_service_authorization_strmap_item_free(void *service_auth
)
850 rend_service_authorization_free(service_auth
);
853 /** Release all the storage held in auth_hid_servs.
856 rend_service_authorization_free_all(void)
858 if (!auth_hid_servs
) {
861 strmap_free(auth_hid_servs
, rend_service_authorization_strmap_item_free
);
862 auth_hid_servs
= NULL
;
865 /** Parse <b>config_line</b> as a client-side authorization for a hidden
866 * service and add it to the local map of hidden service authorizations.
867 * Return 0 for success and -1 for failure. */
869 rend_parse_service_authorization(or_options_t
*options
, int validate_only
)
873 strmap_t
*parsed
= strmap_new();
874 smartlist_t
*sl
= smartlist_create();
875 rend_service_authorization_t
*auth
= NULL
;
877 for (line
= options
->HidServAuth
; line
; line
= line
->next
) {
878 char *onion_address
, *descriptor_cookie
;
879 char descriptor_cookie_tmp
[REND_DESC_COOKIE_LEN
+2];
880 char descriptor_cookie_base64ext
[REND_DESC_COOKIE_LEN_BASE64
+2+1];
881 int auth_type_val
= 0;
883 SMARTLIST_FOREACH(sl
, char *, c
, tor_free(c
););
885 smartlist_split_string(sl
, line
->value
, " ",
886 SPLIT_SKIP_SPACE
|SPLIT_IGNORE_BLANK
, 3);
887 if (smartlist_len(sl
) < 2) {
888 log_warn(LD_CONFIG
, "Configuration line does not consist of "
889 "\"onion-address authorization-cookie [service-name]\": "
890 "'%s'", line
->value
);
893 auth
= tor_malloc_zero(sizeof(rend_service_authorization_t
));
894 /* Parse onion address. */
895 onion_address
= smartlist_get(sl
, 0);
896 if (strlen(onion_address
) != REND_SERVICE_ADDRESS_LEN
||
897 strcmpend(onion_address
, ".onion")) {
898 log_warn(LD_CONFIG
, "Onion address has wrong format: '%s'",
902 strlcpy(auth
->onion_address
, onion_address
, REND_SERVICE_ID_LEN_BASE32
+1);
903 if (!rend_valid_service_id(auth
->onion_address
)) {
904 log_warn(LD_CONFIG
, "Onion address has wrong format: '%s'",
908 /* Parse descriptor cookie. */
909 descriptor_cookie
= smartlist_get(sl
, 1);
910 if (strlen(descriptor_cookie
) != REND_DESC_COOKIE_LEN_BASE64
) {
911 log_warn(LD_CONFIG
, "Authorization cookie has wrong length: '%s'",
915 /* Add trailing zero bytes (AA) to make base64-decoding happy. */
916 tor_snprintf(descriptor_cookie_base64ext
,
917 REND_DESC_COOKIE_LEN_BASE64
+2+1,
918 "%sAA", descriptor_cookie
);
919 if (base64_decode(descriptor_cookie_tmp
, sizeof(descriptor_cookie_tmp
),
920 descriptor_cookie_base64ext
,
921 strlen(descriptor_cookie_base64ext
)) < 0) {
922 log_warn(LD_CONFIG
, "Decoding authorization cookie failed: '%s'",
926 auth_type_val
= (descriptor_cookie_tmp
[16] >> 4) + 1;
927 if (auth_type_val
< 1 || auth_type_val
> 2) {
928 log_warn(LD_CONFIG
, "Authorization cookie has unknown authorization "
932 auth
->auth_type
= auth_type_val
== 1 ? REND_BASIC_AUTH
: REND_STEALTH_AUTH
;
933 memcpy(auth
->descriptor_cookie
, descriptor_cookie_tmp
,
934 REND_DESC_COOKIE_LEN
);
935 if (strmap_get(parsed
, auth
->onion_address
)) {
936 log_warn(LD_CONFIG
, "Duplicate authorization for the same hidden "
940 strmap_set(parsed
, auth
->onion_address
, auth
);
949 rend_service_authorization_free(auth
);
950 SMARTLIST_FOREACH(sl
, char *, c
, tor_free(c
););
952 if (!validate_only
&& res
== 0) {
953 rend_service_authorization_free_all();
954 auth_hid_servs
= parsed
;
956 strmap_free(parsed
, rend_service_authorization_strmap_item_free
);