1 /* Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
2 * Copyright (c) 2007-2011, 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 uint8_t *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
);
358 last_request_ptr
= tor_malloc_zero(sizeof(time_t));
359 *last_request_ptr
= now
;
360 oldptr
= strmap_set(last_hid_serv_requests
, hsdir_desc_comb_id
,
364 last_request_ptr
= strmap_get_lc(last_hid_serv_requests
,
366 return (last_request_ptr
) ? *last_request_ptr
: 0;
369 /** Clean the history of request times to hidden service directories, so that
370 * it does not contain requests older than REND_HID_SERV_DIR_REQUERY_PERIOD
371 * seconds any more. */
373 directory_clean_last_hid_serv_requests(void)
376 time_t cutoff
= time(NULL
) - REND_HID_SERV_DIR_REQUERY_PERIOD
;
377 if (!last_hid_serv_requests
)
378 last_hid_serv_requests
= strmap_new();
379 for (iter
= strmap_iter_init(last_hid_serv_requests
);
380 !strmap_iter_done(iter
); ) {
384 strmap_iter_get(iter
, &key
, &val
);
385 ent
= (time_t *) val
;
387 iter
= strmap_iter_next_rmv(last_hid_serv_requests
, iter
);
390 iter
= strmap_iter_next(last_hid_serv_requests
, iter
);
395 /** Determine the responsible hidden service directories for <b>desc_id</b>
396 * and fetch the descriptor belonging to that ID from one of them. Only
397 * send a request to hidden service directories that we did not try within
398 * the last REND_HID_SERV_DIR_REQUERY_PERIOD seconds; on success, return 1,
399 * in the case that no hidden service directory is left to ask for the
400 * descriptor, return 0, and in case of a failure -1. <b>query</b> is only
401 * passed for pretty log statements. */
403 directory_get_from_hs_dir(const char *desc_id
, const rend_data_t
*rend_query
)
405 smartlist_t
*responsible_dirs
= smartlist_create();
406 routerstatus_t
*hs_dir
;
407 char desc_id_base32
[REND_DESC_ID_V2_LEN_BASE32
+ 1];
408 time_t now
= time(NULL
);
409 char descriptor_cookie_base64
[3*REND_DESC_COOKIE_LEN_BASE64
];
411 tor_assert(rend_query
);
412 /* Determine responsible dirs. Even if we can't get all we want,
413 * work with the ones we have. If it's empty, we'll notice below. */
414 (int) hid_serv_get_responsible_directories(responsible_dirs
, desc_id
);
416 base32_encode(desc_id_base32
, sizeof(desc_id_base32
),
417 desc_id
, DIGEST_LEN
);
419 /* Only select those hidden service directories to which we did not send
420 * a request recently and for which we have a router descriptor here. */
421 directory_clean_last_hid_serv_requests(); /* Clean request history first. */
423 SMARTLIST_FOREACH(responsible_dirs
, routerstatus_t
*, dir
, {
424 if (lookup_last_hid_serv_request(dir
, desc_id_base32
, 0, 0) +
425 REND_HID_SERV_DIR_REQUERY_PERIOD
>= now
||
426 !router_get_by_digest(dir
->identity_digest
))
427 SMARTLIST_DEL_CURRENT(responsible_dirs
, dir
);
430 hs_dir
= smartlist_choose(responsible_dirs
);
431 smartlist_free(responsible_dirs
);
433 log_info(LD_REND
, "Could not pick one of the responsible hidden "
434 "service directories, because we requested them all "
435 "recently without success.");
439 /* Remember, that we are requesting a descriptor from this hidden service
441 lookup_last_hid_serv_request(hs_dir
, desc_id_base32
, now
, 1);
443 /* Encode descriptor cookie for logging purposes. */
444 if (rend_query
->auth_type
!= REND_NO_AUTH
) {
445 if (base64_encode(descriptor_cookie_base64
,
446 sizeof(descriptor_cookie_base64
),
447 rend_query
->descriptor_cookie
, REND_DESC_COOKIE_LEN
)<0) {
448 log_warn(LD_BUG
, "Could not base64-encode descriptor cookie.");
451 /* Remove == signs and newline. */
452 descriptor_cookie_base64
[strlen(descriptor_cookie_base64
)-3] = '\0';
454 strlcpy(descriptor_cookie_base64
, "(none)",
455 sizeof(descriptor_cookie_base64
));
458 /* Send fetch request. (Pass query and possibly descriptor cookie so that
459 * they can be written to the directory connection and be referred to when
460 * the response arrives. */
461 directory_initiate_command_routerstatus_rend(hs_dir
,
462 DIR_PURPOSE_FETCH_RENDDESC_V2
,
463 ROUTER_PURPOSE_GENERAL
,
464 1, desc_id_base32
, NULL
, 0, 0,
466 log_info(LD_REND
, "Sending fetch request for v2 descriptor for "
467 "service '%s' with descriptor ID '%s', auth type %d, "
468 "and descriptor cookie '%s' to hidden service "
469 "directory '%s' on port %d.",
470 rend_query
->onion_address
, desc_id_base32
,
471 rend_query
->auth_type
,
472 (rend_query
->auth_type
== REND_NO_AUTH
? "[none]" :
473 escaped_safe_str(descriptor_cookie_base64
)),
474 hs_dir
->nickname
, hs_dir
->dir_port
);
478 /** If we are not currently fetching a rendezvous service descriptor
479 * for the service ID <b>query</b>, start a directory connection to fetch a
483 rend_client_refetch_renddesc(const char *query
)
485 if (!get_options()->FetchHidServDescriptors
)
487 log_info(LD_REND
, "Fetching rendezvous descriptor for service %s",
488 escaped_safe_str(query
));
489 if (connection_get_by_type_state_rendquery(CONN_TYPE_DIR
, 0, query
, 0)) {
490 log_info(LD_REND
,"Would fetch a new renddesc here (for %s), but one is "
491 "already in progress.", escaped_safe_str(query
));
493 /* not one already; initiate a dir rend desc lookup */
494 directory_get_from_dirserver(DIR_PURPOSE_FETCH_RENDDESC
,
495 ROUTER_PURPOSE_GENERAL
, query
,
496 PDS_RETRY_IF_NO_SERVERS
);
500 /** Start a connection to a hidden service directory to fetch a v2
501 * rendezvous service descriptor for the base32-encoded service ID
505 rend_client_refetch_v2_renddesc(const rend_data_t
*rend_query
)
507 char descriptor_id
[DIGEST_LEN
];
508 int replicas_left_to_try
[REND_NUMBER_OF_NON_CONSECUTIVE_REPLICAS
];
509 int i
, tries_left
, r
;
510 rend_cache_entry_t
*e
= NULL
;
511 time_t now
= time(NULL
);
512 tor_assert(rend_query
);
513 /* Are we configured to fetch descriptors? */
514 if (!get_options()->FetchHidServDescriptors
) {
515 log_warn(LD_REND
, "We received an onion address for a v2 rendezvous "
516 "service descriptor, but are not fetching service descriptors.");
519 /* Before fetching, check if we already have the descriptor here. */
520 r
= rend_cache_lookup_entry(rend_query
->onion_address
, -1, &e
);
521 if (r
> 0 && now
- e
->received
< NUM_SECONDS_BEFORE_HS_REFETCH
) {
522 log_info(LD_REND
, "We would fetch a v2 rendezvous descriptor, but we "
523 "already have a fresh copy of that descriptor here. "
527 log_debug(LD_REND
, "Fetching v2 rendezvous descriptor for service %s",
528 safe_str(rend_query
->onion_address
));
529 /* Randomly iterate over the replicas until a descriptor can be fetched
530 * from one of the consecutive nodes, or no options are left. */
531 tries_left
= REND_NUMBER_OF_NON_CONSECUTIVE_REPLICAS
;
532 for (i
= 0; i
< REND_NUMBER_OF_NON_CONSECUTIVE_REPLICAS
; i
++)
533 replicas_left_to_try
[i
] = i
;
534 while (tries_left
> 0) {
535 int rand
= crypto_rand_int(tries_left
);
536 int chosen_replica
= replicas_left_to_try
[rand
];
537 replicas_left_to_try
[rand
] = replicas_left_to_try
[--tries_left
];
539 if (rend_compute_v2_desc_id(descriptor_id
, rend_query
->onion_address
,
540 rend_query
->auth_type
== REND_STEALTH_AUTH
?
541 rend_query
->descriptor_cookie
: NULL
,
542 time(NULL
), chosen_replica
) < 0) {
543 log_warn(LD_REND
, "Internal error: Computing v2 rendezvous "
544 "descriptor ID did not succeed.");
547 if (directory_get_from_hs_dir(descriptor_id
, rend_query
) != 0)
548 return; /* either success or failure, but we're done */
550 /* If we come here, there are no hidden service directories left. */
551 log_info(LD_REND
, "Could not pick one of the responsible hidden "
552 "service directories to fetch descriptors, because "
553 "we already tried them all unsuccessfully.");
554 /* Close pending connections (unless a v0 request is still going on). */
555 rend_client_desc_trynow(rend_query
->onion_address
, 2);
559 /** Remove failed_intro from ent. If ent now has no intro points, or
560 * service is unrecognized, then launch a new renddesc fetch.
562 * Return -1 if error, 0 if no intro points remain or service
563 * unrecognized, 1 if recognized and some intro points remain.
566 rend_client_remove_intro_point(extend_info_t
*failed_intro
,
567 const rend_data_t
*rend_query
)
570 rend_cache_entry_t
*ent
;
573 r
= rend_cache_lookup_entry(rend_query
->onion_address
, -1, &ent
);
575 log_warn(LD_BUG
, "Malformed service ID %s.",
576 escaped_safe_str(rend_query
->onion_address
));
580 log_info(LD_REND
, "Unknown service %s. Re-fetching descriptor.",
581 escaped_safe_str(rend_query
->onion_address
));
582 /* Fetch both, v0 and v2 rend descriptors in parallel. Use whichever
583 * arrives first. Exception: When using client authorization, only
584 * fetch v2 descriptors.*/
585 rend_client_refetch_v2_renddesc(rend_query
);
586 if (rend_query
->auth_type
== REND_NO_AUTH
)
587 rend_client_refetch_renddesc(rend_query
->onion_address
);
591 for (i
= 0; i
< smartlist_len(ent
->parsed
->intro_nodes
); i
++) {
592 rend_intro_point_t
*intro
= smartlist_get(ent
->parsed
->intro_nodes
, i
);
593 if (!memcmp(failed_intro
->identity_digest
,
594 intro
->extend_info
->identity_digest
, DIGEST_LEN
)) {
595 rend_intro_point_free(intro
);
596 smartlist_del(ent
->parsed
->intro_nodes
, i
);
601 if (smartlist_len(ent
->parsed
->intro_nodes
) == 0) {
603 "No more intro points remain for %s. Re-fetching descriptor.",
604 escaped_safe_str(rend_query
->onion_address
));
605 /* Fetch both, v0 and v2 rend descriptors in parallel. Use whichever
606 * arrives first. Exception: When using client authorization, only
607 * fetch v2 descriptors.*/
608 rend_client_refetch_v2_renddesc(rend_query
);
609 if (rend_query
->auth_type
== REND_NO_AUTH
)
610 rend_client_refetch_renddesc(rend_query
->onion_address
);
612 /* move all pending streams back to renddesc_wait */
613 while ((conn
= connection_get_by_type_state_rendquery(CONN_TYPE_AP
,
614 AP_CONN_STATE_CIRCUIT_WAIT
,
615 rend_query
->onion_address
, -1))) {
616 conn
->state
= AP_CONN_STATE_RENDDESC_WAIT
;
621 log_info(LD_REND
,"%d options left for %s.",
622 smartlist_len(ent
->parsed
->intro_nodes
),
623 escaped_safe_str(rend_query
->onion_address
));
627 /** Called when we receive a RENDEZVOUS_ESTABLISHED cell; changes the state of
628 * the circuit to C_REND_READY.
631 rend_client_rendezvous_acked(origin_circuit_t
*circ
, const uint8_t *request
,
636 /* we just got an ack for our establish-rendezvous. switch purposes. */
637 if (circ
->_base
.purpose
!= CIRCUIT_PURPOSE_C_ESTABLISH_REND
) {
638 log_warn(LD_PROTOCOL
,"Got a rendezvous ack when we weren't expecting one. "
640 circuit_mark_for_close(TO_CIRCUIT(circ
), END_CIRC_REASON_TORPROTOCOL
);
643 log_info(LD_REND
,"Got rendezvous ack. This circuit is now ready for "
645 circ
->_base
.purpose
= CIRCUIT_PURPOSE_C_REND_READY
;
646 /* XXXX022 This is a pretty brute-force approach. It'd be better to
647 * attach only the connections that are waiting on this circuit, rather
648 * than trying to attach them all. See comments bug 743. */
649 /* If we already have the introduction circuit built, make sure we send
650 * the INTRODUCE cell _now_ */
651 connection_ap_attach_pending();
655 /** Bob sent us a rendezvous cell; join the circuits. */
657 rend_client_receive_rendezvous(origin_circuit_t
*circ
, const uint8_t *request
,
661 char keys
[DIGEST_LEN
+CPATH_KEY_MATERIAL_LEN
];
663 if ((circ
->_base
.purpose
!= CIRCUIT_PURPOSE_C_REND_READY
&&
664 circ
->_base
.purpose
!= CIRCUIT_PURPOSE_C_REND_READY_INTRO_ACKED
)
665 || !circ
->build_state
->pending_final_cpath
) {
666 log_warn(LD_PROTOCOL
,"Got rendezvous2 cell from hidden service, but not "
667 "expecting it. Closing.");
668 circuit_mark_for_close(TO_CIRCUIT(circ
), END_CIRC_REASON_TORPROTOCOL
);
672 if (request_len
!= DH_KEY_LEN
+DIGEST_LEN
) {
673 log_warn(LD_PROTOCOL
,"Incorrect length (%d) on RENDEZVOUS2 cell.",
678 log_info(LD_REND
,"Got RENDEZVOUS2 cell from hidden service.");
680 /* first DH_KEY_LEN bytes are g^y from bob. Finish the dh handshake...*/
681 tor_assert(circ
->build_state
);
682 tor_assert(circ
->build_state
->pending_final_cpath
);
683 hop
= circ
->build_state
->pending_final_cpath
;
684 tor_assert(hop
->dh_handshake_state
);
685 if (crypto_dh_compute_secret(hop
->dh_handshake_state
, (char*)request
,
687 keys
, DIGEST_LEN
+CPATH_KEY_MATERIAL_LEN
)<0) {
688 log_warn(LD_GENERAL
, "Couldn't complete DH handshake.");
691 /* ... and set up cpath. */
692 if (circuit_init_cpath_crypto(hop
, keys
+DIGEST_LEN
, 0)<0)
695 /* Check whether the digest is right... */
696 if (memcmp(keys
, request
+DH_KEY_LEN
, DIGEST_LEN
)) {
697 log_warn(LD_PROTOCOL
, "Incorrect digest of key material.");
701 crypto_dh_free(hop
->dh_handshake_state
);
702 hop
->dh_handshake_state
= NULL
;
704 /* All is well. Extend the circuit. */
705 circ
->_base
.purpose
= CIRCUIT_PURPOSE_C_REND_JOINED
;
706 hop
->state
= CPATH_STATE_OPEN
;
707 /* set the windows to default. these are the windows
708 * that alice thinks bob has.
710 hop
->package_window
= circuit_initial_package_window();
711 hop
->deliver_window
= CIRCWINDOW_START
;
713 onion_append_to_cpath(&circ
->cpath
, hop
);
714 circ
->build_state
->pending_final_cpath
= NULL
; /* prevent double-free */
715 /* XXXX022 This is a pretty brute-force approach. It'd be better to
716 * attach only the connections that are waiting on this circuit, rather
717 * than trying to attach them all. See comments bug 743. */
718 connection_ap_attach_pending();
721 circuit_mark_for_close(TO_CIRCUIT(circ
), END_CIRC_REASON_TORPROTOCOL
);
725 /** Find all the apconns in state AP_CONN_STATE_RENDDESC_WAIT that
726 * are waiting on query. If there's a working cache entry here
727 * with at least one intro point, move them to the next state. If
728 * <b>rend_version</b> is non-negative, fail connections that have
729 * requested <b>query</b> unless there are still descriptor fetch
730 * requests in progress for other descriptor versions than
731 * <b>rend_version</b>.
734 rend_client_desc_trynow(const char *query
, int rend_version
)
736 edge_connection_t
*conn
;
737 rend_cache_entry_t
*entry
;
738 time_t now
= time(NULL
);
740 smartlist_t
*conns
= get_connection_array();
741 SMARTLIST_FOREACH(conns
, connection_t
*, _conn
,
743 if (_conn
->type
!= CONN_TYPE_AP
||
744 _conn
->state
!= AP_CONN_STATE_RENDDESC_WAIT
||
745 _conn
->marked_for_close
)
747 conn
= TO_EDGE_CONN(_conn
);
748 if (!conn
->rend_data
)
750 if (rend_cmp_service_ids(query
, conn
->rend_data
->onion_address
))
752 assert_connection_ok(TO_CONN(conn
), now
);
753 if (rend_cache_lookup_entry(conn
->rend_data
->onion_address
, -1,
755 smartlist_len(entry
->parsed
->intro_nodes
) > 0) {
756 /* either this fetch worked, or it failed but there was a
757 * valid entry from before which we should reuse */
758 log_info(LD_REND
,"Rend desc is usable. Launching circuits.");
759 conn
->_base
.state
= AP_CONN_STATE_CIRCUIT_WAIT
;
761 /* restart their timeout values, so they get a fair shake at
762 * connecting to the hidden service. */
763 conn
->_base
.timestamp_created
= now
;
764 conn
->_base
.timestamp_lastread
= now
;
765 conn
->_base
.timestamp_lastwritten
= now
;
767 if (connection_ap_handshake_attach_circuit(conn
) < 0) {
768 /* it will never work */
769 log_warn(LD_REND
,"Rendezvous attempt failed. Closing.");
770 if (!conn
->_base
.marked_for_close
)
771 connection_mark_unattached_ap(conn
, END_STREAM_REASON_CANT_ATTACH
);
773 } else { /* 404, or fetch didn't get that far */
774 /* Unless there are requests for another descriptor version pending,
775 * close the connection. */
776 if (rend_version
>= 0 &&
777 !connection_get_by_type_state_rendquery(CONN_TYPE_DIR
, 0, query
,
778 rend_version
== 0 ? 2 : 0)) {
779 log_notice(LD_REND
,"Closing stream for '%s.onion': hidden service is "
780 "unavailable (try again later).", safe_str(query
));
781 connection_mark_unattached_ap(conn
, END_STREAM_REASON_RESOLVEFAILED
);
787 /** Return a newly allocated extend_info_t* for a randomly chosen introduction
788 * point for the named hidden service. Return NULL if all introduction points
789 * have been tried and failed.
792 rend_client_get_random_intro(const rend_data_t
*rend_query
)
795 rend_cache_entry_t
*entry
;
796 rend_intro_point_t
*intro
;
797 routerinfo_t
*router
;
799 if (rend_cache_lookup_entry(rend_query
->onion_address
, -1, &entry
) < 1) {
801 "Query '%s' didn't have valid rend desc in cache. Failing.",
802 safe_str(rend_query
->onion_address
));
807 if (smartlist_len(entry
->parsed
->intro_nodes
) == 0)
810 i
= crypto_rand_int(smartlist_len(entry
->parsed
->intro_nodes
));
811 intro
= smartlist_get(entry
->parsed
->intro_nodes
, i
);
812 /* Do we need to look up the router or is the extend info complete? */
813 if (!intro
->extend_info
->onion_key
) {
814 router
= router_get_by_nickname(intro
->extend_info
->nickname
, 0);
816 log_info(LD_REND
, "Unknown router with nickname '%s'; trying another.",
817 intro
->extend_info
->nickname
);
818 rend_intro_point_free(intro
);
819 smartlist_del(entry
->parsed
->intro_nodes
, i
);
822 extend_info_free(intro
->extend_info
);
823 intro
->extend_info
= extend_info_from_router(router
);
825 return extend_info_dup(intro
->extend_info
);
828 /** Client-side authorizations for hidden services; map of onion address to
829 * rend_service_authorization_t*. */
830 static strmap_t
*auth_hid_servs
= NULL
;
832 /** Look up the client-side authorization for the hidden service with
833 * <b>onion_address</b>. Return NULL if no authorization is available for
835 rend_service_authorization_t
*
836 rend_client_lookup_service_authorization(const char *onion_address
)
838 tor_assert(onion_address
);
839 if (!auth_hid_servs
) return NULL
;
840 return strmap_get(auth_hid_servs
, onion_address
);
843 /** Helper: Free storage held by rend_service_authorization_t. */
845 rend_service_authorization_free(rend_service_authorization_t
*auth
)
850 /** Helper for strmap_free. */
852 rend_service_authorization_strmap_item_free(void *service_auth
)
854 rend_service_authorization_free(service_auth
);
857 /** Release all the storage held in auth_hid_servs.
860 rend_service_authorization_free_all(void)
862 if (!auth_hid_servs
) {
865 strmap_free(auth_hid_servs
, rend_service_authorization_strmap_item_free
);
866 auth_hid_servs
= NULL
;
869 /** Parse <b>config_line</b> as a client-side authorization for a hidden
870 * service and add it to the local map of hidden service authorizations.
871 * Return 0 for success and -1 for failure. */
873 rend_parse_service_authorization(or_options_t
*options
, int validate_only
)
877 strmap_t
*parsed
= strmap_new();
878 smartlist_t
*sl
= smartlist_create();
879 rend_service_authorization_t
*auth
= NULL
;
881 for (line
= options
->HidServAuth
; line
; line
= line
->next
) {
882 char *onion_address
, *descriptor_cookie
;
883 char descriptor_cookie_tmp
[REND_DESC_COOKIE_LEN
+2];
884 char descriptor_cookie_base64ext
[REND_DESC_COOKIE_LEN_BASE64
+2+1];
885 int auth_type_val
= 0;
887 SMARTLIST_FOREACH(sl
, char *, c
, tor_free(c
););
889 smartlist_split_string(sl
, line
->value
, " ",
890 SPLIT_SKIP_SPACE
|SPLIT_IGNORE_BLANK
, 3);
891 if (smartlist_len(sl
) < 2) {
892 log_warn(LD_CONFIG
, "Configuration line does not consist of "
893 "\"onion-address authorization-cookie [service-name]\": "
894 "'%s'", line
->value
);
897 auth
= tor_malloc_zero(sizeof(rend_service_authorization_t
));
898 /* Parse onion address. */
899 onion_address
= smartlist_get(sl
, 0);
900 if (strlen(onion_address
) != REND_SERVICE_ADDRESS_LEN
||
901 strcmpend(onion_address
, ".onion")) {
902 log_warn(LD_CONFIG
, "Onion address has wrong format: '%s'",
906 strlcpy(auth
->onion_address
, onion_address
, REND_SERVICE_ID_LEN_BASE32
+1);
907 if (!rend_valid_service_id(auth
->onion_address
)) {
908 log_warn(LD_CONFIG
, "Onion address has wrong format: '%s'",
912 /* Parse descriptor cookie. */
913 descriptor_cookie
= smartlist_get(sl
, 1);
914 if (strlen(descriptor_cookie
) != REND_DESC_COOKIE_LEN_BASE64
) {
915 log_warn(LD_CONFIG
, "Authorization cookie has wrong length: '%s'",
919 /* Add trailing zero bytes (AA) to make base64-decoding happy. */
920 tor_snprintf(descriptor_cookie_base64ext
,
921 REND_DESC_COOKIE_LEN_BASE64
+2+1,
922 "%sAA", descriptor_cookie
);
923 if (base64_decode(descriptor_cookie_tmp
, sizeof(descriptor_cookie_tmp
),
924 descriptor_cookie_base64ext
,
925 strlen(descriptor_cookie_base64ext
)) < 0) {
926 log_warn(LD_CONFIG
, "Decoding authorization cookie failed: '%s'",
930 auth_type_val
= (descriptor_cookie_tmp
[16] >> 4) + 1;
931 if (auth_type_val
< 1 || auth_type_val
> 2) {
932 log_warn(LD_CONFIG
, "Authorization cookie has unknown authorization "
936 auth
->auth_type
= auth_type_val
== 1 ? REND_BASIC_AUTH
: REND_STEALTH_AUTH
;
937 memcpy(auth
->descriptor_cookie
, descriptor_cookie_tmp
,
938 REND_DESC_COOKIE_LEN
);
939 if (strmap_get(parsed
, auth
->onion_address
)) {
940 log_warn(LD_CONFIG
, "Duplicate authorization for the same hidden "
944 strmap_set(parsed
, auth
->onion_address
, auth
);
953 rend_service_authorization_free(auth
);
954 SMARTLIST_FOREACH(sl
, char *, c
, tor_free(c
););
956 if (!validate_only
&& res
== 0) {
957 rend_service_authorization_free_all();
958 auth_hid_servs
= parsed
;
960 strmap_free(parsed
, rend_service_authorization_strmap_item_free
);