1 /* Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
2 * Copyright (c) 2007-2008, 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) { /* unversioned 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 log_warn(LD_BUG
, "Internal error: could not find intro key.");
101 if (crypto_pk_get_digest(intro_key
, payload
)<0) {
102 log_warn(LD_BUG
, "Internal error: couldn't hash public key.");
106 /* Initialize the pending_final_cpath and start the DH handshake. */
107 cpath
= rendcirc
->build_state
->pending_final_cpath
;
109 cpath
= rendcirc
->build_state
->pending_final_cpath
=
110 tor_malloc_zero(sizeof(crypt_path_t
));
111 cpath
->magic
= CRYPT_PATH_MAGIC
;
112 if (!(cpath
->dh_handshake_state
= crypto_dh_new())) {
113 log_warn(LD_BUG
, "Internal error: couldn't allocate DH.");
116 if (crypto_dh_generate_public(cpath
->dh_handshake_state
)<0) {
117 log_warn(LD_BUG
, "Internal error: couldn't generate g^x.");
122 /* If version is 3, write (optional) auth data and timestamp. */
123 if (entry
->parsed
->protocols
& (1<<3)) {
124 tmp
[0] = 3; /* version 3 of the cell format */
125 tmp
[1] = (uint8_t)introcirc
->rend_data
->auth_type
; /* auth type, if any */
127 if (introcirc
->rend_data
->auth_type
!= REND_NO_AUTH
) {
128 set_uint16(tmp
+2, htons(REND_DESC_COOKIE_LEN
));
129 memcpy(tmp
+4, introcirc
->rend_data
->descriptor_cookie
,
130 REND_DESC_COOKIE_LEN
);
131 v3_shift
+= 2+REND_DESC_COOKIE_LEN
;
133 set_uint32(tmp
+v3_shift
+1, htonl(time(NULL
)));
135 } /* if version 2 only write version number */
136 else if (entry
->parsed
->protocols
& (1<<2)) {
137 tmp
[0] = 2; /* version 2 of the cell format */
140 /* write the remaining items into tmp */
141 if (entry
->parsed
->protocols
& (1<<3) || entry
->parsed
->protocols
& (1<<2)) {
142 /* version 2 format */
143 extend_info_t
*extend_info
= rendcirc
->build_state
->chosen_exit
;
146 set_uint32(tmp
+v3_shift
+1, tor_addr_to_ipv4h(&extend_info
->addr
));
147 set_uint16(tmp
+v3_shift
+5, htons(extend_info
->port
));
148 memcpy(tmp
+v3_shift
+7, extend_info
->identity_digest
, DIGEST_LEN
);
149 klen
= crypto_pk_asn1_encode(extend_info
->onion_key
,
150 tmp
+v3_shift
+7+DIGEST_LEN
+2,
151 sizeof(tmp
)-(v3_shift
+7+DIGEST_LEN
+2));
152 set_uint16(tmp
+v3_shift
+7+DIGEST_LEN
, htons(klen
));
153 memcpy(tmp
+v3_shift
+7+DIGEST_LEN
+2+klen
, rendcirc
->rend_data
->rend_cookie
,
155 dh_offset
= v3_shift
+7+DIGEST_LEN
+2+klen
+REND_COOKIE_LEN
;
158 strncpy(tmp
, rendcirc
->build_state
->chosen_exit
->nickname
,
159 (MAX_NICKNAME_LEN
+1)); /* nul pads */
160 memcpy(tmp
+MAX_NICKNAME_LEN
+1, rendcirc
->rend_data
->rend_cookie
,
162 dh_offset
= MAX_NICKNAME_LEN
+1+REND_COOKIE_LEN
;
165 if (crypto_dh_get_public(cpath
->dh_handshake_state
, tmp
+dh_offset
,
167 log_warn(LD_BUG
, "Internal error: couldn't extract g^x.");
171 note_crypto_pk_op(REND_CLIENT
);
172 /*XXX maybe give crypto_pk_public_hybrid_encrypt a max_len arg,
173 * to avoid buffer overflows? */
174 r
= crypto_pk_public_hybrid_encrypt(intro_key
, payload
+DIGEST_LEN
,
176 (int)(dh_offset
+DH_KEY_LEN
),
177 PK_PKCS1_OAEP_PADDING
, 0);
179 log_warn(LD_BUG
,"Internal error: hybrid pk encrypt failed.");
183 payload_len
= DIGEST_LEN
+ r
;
184 tor_assert(payload_len
<= RELAY_PAYLOAD_SIZE
); /* we overran something */
186 log_info(LD_REND
, "Sending an INTRODUCE1 cell");
187 if (relay_send_command_from_edge(0, TO_CIRCUIT(introcirc
),
188 RELAY_COMMAND_INTRODUCE1
,
189 payload
, payload_len
,
190 introcirc
->cpath
->prev
)<0) {
191 /* introcirc is already marked for close. leave rendcirc alone. */
192 log_warn(LD_BUG
, "Couldn't send INTRODUCE1 cell");
196 /* Now, we wait for an ACK or NAK on this circuit. */
197 introcirc
->_base
.purpose
= CIRCUIT_PURPOSE_C_INTRODUCE_ACK_WAIT
;
201 circuit_mark_for_close(TO_CIRCUIT(introcirc
), END_CIRC_REASON_INTERNAL
);
202 circuit_mark_for_close(TO_CIRCUIT(rendcirc
), END_CIRC_REASON_INTERNAL
);
206 /** Called when a rendezvous circuit is open; sends a establish
207 * rendezvous circuit as appropriate. */
209 rend_client_rendcirc_has_opened(origin_circuit_t
*circ
)
211 tor_assert(circ
->_base
.purpose
== CIRCUIT_PURPOSE_C_ESTABLISH_REND
);
213 log_info(LD_REND
,"rendcirc is open");
215 /* generate a rendezvous cookie, store it in circ */
216 if (rend_client_send_establish_rendezvous(circ
) < 0) {
221 /** Called when get an ACK or a NAK for a REND_INTRODUCE1 cell.
224 rend_client_introduction_acked(origin_circuit_t
*circ
,
225 const char *request
, size_t request_len
)
227 origin_circuit_t
*rendcirc
;
228 (void) request
; // XXXX Use this.
230 if (circ
->_base
.purpose
!= CIRCUIT_PURPOSE_C_INTRODUCE_ACK_WAIT
) {
231 log_warn(LD_PROTOCOL
,
232 "Received REND_INTRODUCE_ACK on unexpected circuit %d.",
233 circ
->_base
.n_circ_id
);
234 circuit_mark_for_close(TO_CIRCUIT(circ
), END_CIRC_REASON_TORPROTOCOL
);
238 tor_assert(circ
->build_state
->chosen_exit
);
239 tor_assert(circ
->rend_data
);
241 if (request_len
== 0) {
242 /* It's an ACK; the introduction point relayed our introduction request. */
243 /* Locate the rend circ which is waiting to hear about this ack,
246 log_info(LD_REND
,"Received ack. Telling rend circ...");
247 rendcirc
= circuit_get_by_rend_query_and_purpose(
248 circ
->rend_data
->onion_address
, CIRCUIT_PURPOSE_C_REND_READY
);
249 if (rendcirc
) { /* remember the ack */
250 rendcirc
->_base
.purpose
= CIRCUIT_PURPOSE_C_REND_READY_INTRO_ACKED
;
252 log_info(LD_REND
,"...Found no rend circ. Dropping on the floor.");
254 /* close the circuit: we won't need it anymore. */
255 circ
->_base
.purpose
= CIRCUIT_PURPOSE_C_INTRODUCE_ACKED
;
256 circuit_mark_for_close(TO_CIRCUIT(circ
), END_CIRC_REASON_FINISHED
);
258 /* It's a NAK; the introduction point didn't relay our request. */
259 circ
->_base
.purpose
= CIRCUIT_PURPOSE_C_INTRODUCING
;
260 /* Remove this intro point from the set of viable introduction
261 * points. If any remain, extend to a new one and try again.
262 * If none remain, refetch the service descriptor.
264 if (rend_client_remove_intro_point(circ
->build_state
->chosen_exit
,
265 circ
->rend_data
) > 0) {
266 /* There are introduction points left. Re-extend the circuit to
267 * another intro point and try again. */
268 extend_info_t
*extend_info
;
270 extend_info
= rend_client_get_random_intro(circ
->rend_data
);
272 log_warn(LD_REND
, "No introduction points left for %s. Closing.",
273 escaped_safe_str(circ
->rend_data
->onion_address
));
274 circuit_mark_for_close(TO_CIRCUIT(circ
), END_CIRC_REASON_INTERNAL
);
278 "Got nack for %s from %s. Re-extending circ %d, "
280 escaped_safe_str(circ
->rend_data
->onion_address
),
281 circ
->build_state
->chosen_exit
->nickname
, circ
->_base
.n_circ_id
,
282 extend_info
->nickname
);
283 result
= circuit_extend_to_new_exit(circ
, extend_info
);
284 extend_info_free(extend_info
);
291 /** The period for which a hidden service directory cannot be queried for
292 * the same descriptor ID again. */
293 #define REND_HID_SERV_DIR_REQUERY_PERIOD (15 * 60)
295 /** Contains the last request times to hidden service directories for
296 * certain queries; keys are strings consisting of base32-encoded
297 * hidden service directory identities and base32-encoded descriptor IDs;
298 * values are pointers to timestamps of the last requests. */
299 static strmap_t
*last_hid_serv_requests
= NULL
;
301 /** Look up the last request time to hidden service directory <b>hs_dir</b>
302 * for descriptor ID <b>desc_id_base32</b>. If <b>set</b> is non-zero,
303 * assign the current time <b>now</b> and return that. Otherwise, return
304 * the most recent request time, or 0 if no such request has been sent
307 lookup_last_hid_serv_request(routerstatus_t
*hs_dir
,
308 const char *desc_id_base32
, time_t now
, int set
)
310 char hsdir_id_base32
[REND_DESC_ID_V2_LEN_BASE32
+ 1];
311 char hsdir_desc_comb_id
[2 * REND_DESC_ID_V2_LEN_BASE32
+ 1];
312 time_t *last_request_ptr
;
313 base32_encode(hsdir_id_base32
, sizeof(hsdir_id_base32
),
314 hs_dir
->identity_digest
, DIGEST_LEN
);
315 tor_snprintf(hsdir_desc_comb_id
, sizeof(hsdir_desc_comb_id
), "%s%s",
316 hsdir_id_base32
, desc_id_base32
);
318 last_request_ptr
= tor_malloc_zero(sizeof(time_t *));
319 *last_request_ptr
= now
;
320 strmap_set(last_hid_serv_requests
, hsdir_desc_comb_id
, last_request_ptr
);
322 last_request_ptr
= strmap_get_lc(last_hid_serv_requests
,
324 return (last_request_ptr
) ? *last_request_ptr
: 0;
327 /** Clean the history of request times to hidden service directories, so that
328 * it does not contain requests older than REND_HID_SERV_DIR_REQUERY_PERIOD
329 * seconds any more. */
331 directory_clean_last_hid_serv_requests(void)
334 time_t cutoff
= time(NULL
) - REND_HID_SERV_DIR_REQUERY_PERIOD
;
335 if (!last_hid_serv_requests
)
336 last_hid_serv_requests
= strmap_new();
337 for (iter
= strmap_iter_init(last_hid_serv_requests
);
338 !strmap_iter_done(iter
); ) {
342 strmap_iter_get(iter
, &key
, &val
);
343 ent
= (time_t *) val
;
345 iter
= strmap_iter_next_rmv(last_hid_serv_requests
, iter
);
348 iter
= strmap_iter_next(last_hid_serv_requests
, iter
);
353 /** Determine the responsible hidden service directories for <b>desc_id</b>
354 * and fetch the descriptor belonging to that ID from one of them. Only
355 * send a request to hidden service directories that we did not try within
356 * the last REND_HID_SERV_DIR_REQUERY_PERIOD seconds; on success, return 1,
357 * in the case that no hidden service directory is left to ask for the
358 * descriptor, return 0, and in case of a failure -1. <b>query</b> is only
359 * passed for pretty log statements. */
361 directory_get_from_hs_dir(const char *desc_id
, const rend_data_t
*rend_query
)
363 smartlist_t
*responsible_dirs
= smartlist_create();
364 routerstatus_t
*hs_dir
;
365 char desc_id_base32
[REND_DESC_ID_V2_LEN_BASE32
+ 1];
366 time_t now
= time(NULL
);
367 char descriptor_cookie_base64
[3*REND_DESC_COOKIE_LEN_BASE64
];
369 tor_assert(rend_query
);
370 /* Determine responsible dirs. Even if we can't get all we want,
371 * work with the ones we have. If it's empty, we'll notice below. */
372 (int) hid_serv_get_responsible_directories(responsible_dirs
, desc_id
);
374 base32_encode(desc_id_base32
, sizeof(desc_id_base32
),
375 desc_id
, DIGEST_LEN
);
377 /* Only select those hidden service directories to which we did not send
378 * a request recently and for which we have a router descriptor here. */
379 directory_clean_last_hid_serv_requests(); /* Clean request history first. */
381 SMARTLIST_FOREACH(responsible_dirs
, routerstatus_t
*, dir
, {
382 if (lookup_last_hid_serv_request(dir
, desc_id_base32
, 0, 0) +
383 REND_HID_SERV_DIR_REQUERY_PERIOD
>= now
||
384 !router_get_by_digest(dir
->identity_digest
))
385 SMARTLIST_DEL_CURRENT(responsible_dirs
, dir
);
388 hs_dir
= smartlist_choose(responsible_dirs
);
389 smartlist_free(responsible_dirs
);
391 log_info(LD_REND
, "Could not pick one of the responsible hidden "
392 "service directories, because we requested them all "
393 "recently without success.");
397 /* Remember, that we are requesting a descriptor from this hidden service
399 lookup_last_hid_serv_request(hs_dir
, desc_id_base32
, now
, 1);
401 /* Encode descriptor cookie for logging purposes. */
402 if (rend_query
->auth_type
!= REND_NO_AUTH
) {
403 if (base64_encode(descriptor_cookie_base64
,
404 sizeof(descriptor_cookie_base64
),
405 rend_query
->descriptor_cookie
, REND_DESC_COOKIE_LEN
)<0) {
406 log_warn(LD_BUG
, "Could not base64-encode descriptor cookie.");
409 /* Remove == signs and newline. */
410 descriptor_cookie_base64
[strlen(descriptor_cookie_base64
)-3] = '\0';
412 strlcpy(descriptor_cookie_base64
, "(none)",
413 sizeof(descriptor_cookie_base64
));
416 /* Send fetch request. (Pass query and possibly descriptor cookie so that
417 * they can be written to the directory connection and be referred to when
418 * the response arrives. */
419 directory_initiate_command_routerstatus_rend(hs_dir
,
420 DIR_PURPOSE_FETCH_RENDDESC_V2
,
421 ROUTER_PURPOSE_GENERAL
,
422 1, desc_id_base32
, NULL
, 0, 0,
424 log_info(LD_REND
, "Sending fetch request for v2 descriptor for "
425 "service '%s' with descriptor ID '%s', auth type %d, "
426 "and descriptor cookie '%s' to hidden service "
427 "directory '%s' on port %d.",
428 rend_query
->onion_address
, desc_id_base32
,
429 rend_query
->auth_type
,
430 (rend_query
->auth_type
== REND_NO_AUTH
? "[none]" :
431 escaped_safe_str(descriptor_cookie_base64
)),
432 hs_dir
->nickname
, hs_dir
->dir_port
);
436 /** If we are not currently fetching a rendezvous service descriptor
437 * for the service ID <b>query</b>, start a directory connection to fetch a
441 rend_client_refetch_renddesc(const char *query
)
443 if (!get_options()->FetchHidServDescriptors
)
445 log_info(LD_REND
, "Fetching rendezvous descriptor for service %s",
446 escaped_safe_str(query
));
447 if (connection_get_by_type_state_rendquery(CONN_TYPE_DIR
, 0, query
, 0)) {
448 log_info(LD_REND
,"Would fetch a new renddesc here (for %s), but one is "
449 "already in progress.", escaped_safe_str(query
));
451 /* not one already; initiate a dir rend desc lookup */
452 directory_get_from_dirserver(DIR_PURPOSE_FETCH_RENDDESC
,
453 ROUTER_PURPOSE_GENERAL
, query
,
454 PDS_RETRY_IF_NO_SERVERS
);
458 /** Start a connection to a hidden service directory to fetch a v2
459 * rendezvous service descriptor for the base32-encoded service ID
463 rend_client_refetch_v2_renddesc(const rend_data_t
*rend_query
)
465 char descriptor_id
[DIGEST_LEN
];
466 int replicas_left_to_try
[REND_NUMBER_OF_NON_CONSECUTIVE_REPLICAS
];
468 rend_cache_entry_t
*e
= NULL
;
469 tor_assert(rend_query
);
470 /* Are we configured to fetch descriptors? */
471 if (!get_options()->FetchHidServDescriptors
) {
472 log_warn(LD_REND
, "We received an onion address for a v2 rendezvous "
473 "service descriptor, but are not fetching service descriptors.");
476 /* Before fetching, check if we already have the descriptor here. */
477 if (rend_cache_lookup_entry(rend_query
->onion_address
, -1, &e
) > 0) {
478 log_info(LD_REND
, "We would fetch a v2 rendezvous descriptor, but we "
479 "already have that descriptor here. Not fetching.");
482 log_debug(LD_REND
, "Fetching v2 rendezvous descriptor for service %s",
483 safe_str(rend_query
->onion_address
));
484 /* Randomly iterate over the replicas until a descriptor can be fetched
485 * from one of the consecutive nodes, or no options are left. */
486 tries_left
= REND_NUMBER_OF_NON_CONSECUTIVE_REPLICAS
;
487 for (i
= 0; i
< REND_NUMBER_OF_NON_CONSECUTIVE_REPLICAS
; i
++)
488 replicas_left_to_try
[i
] = i
;
489 while (tries_left
> 0) {
490 int rand
= crypto_rand_int(tries_left
);
491 int chosen_replica
= replicas_left_to_try
[rand
];
492 replicas_left_to_try
[rand
] = replicas_left_to_try
[--tries_left
];
494 if (rend_compute_v2_desc_id(descriptor_id
, rend_query
->onion_address
,
495 rend_query
->auth_type
== REND_STEALTH_AUTH
?
496 rend_query
->descriptor_cookie
: NULL
,
497 time(NULL
), chosen_replica
) < 0) {
498 log_warn(LD_REND
, "Internal error: Computing v2 rendezvous "
499 "descriptor ID did not succeed.");
502 if (directory_get_from_hs_dir(descriptor_id
, rend_query
) != 0)
503 return; /* either success or failure, but we're done */
505 /* If we come here, there are no hidden service directories left. */
506 log_info(LD_REND
, "Could not pick one of the responsible hidden "
507 "service directories to fetch descriptors, because "
508 "we already tried them all unsuccessfully.");
509 /* Close pending connections (unless a v0 request is still going on). */
510 rend_client_desc_trynow(rend_query
->onion_address
, 2);
514 /** Remove failed_intro from ent. If ent now has no intro points, or
515 * service is unrecognized, then launch a new renddesc fetch.
517 * Return -1 if error, 0 if no intro points remain or service
518 * unrecognized, 1 if recognized and some intro points remain.
521 rend_client_remove_intro_point(extend_info_t
*failed_intro
,
522 const rend_data_t
*rend_query
)
525 rend_cache_entry_t
*ent
;
528 r
= rend_cache_lookup_entry(rend_query
->onion_address
, -1, &ent
);
530 log_warn(LD_BUG
, "Malformed service ID %s.",
531 escaped_safe_str(rend_query
->onion_address
));
535 log_info(LD_REND
, "Unknown service %s. Re-fetching descriptor.",
536 escaped_safe_str(rend_query
->onion_address
));
537 /* Fetch both, v0 and v2 rend descriptors in parallel. Use whichever
538 * arrives first. Exception: When using client authorization, only
539 * fetch v2 descriptors.*/
540 rend_client_refetch_v2_renddesc(rend_query
);
541 if (rend_query
->auth_type
== REND_NO_AUTH
)
542 rend_client_refetch_renddesc(rend_query
->onion_address
);
546 for (i
= 0; i
< smartlist_len(ent
->parsed
->intro_nodes
); i
++) {
547 rend_intro_point_t
*intro
= smartlist_get(ent
->parsed
->intro_nodes
, i
);
548 if (!memcmp(failed_intro
->identity_digest
,
549 intro
->extend_info
->identity_digest
, DIGEST_LEN
)) {
550 rend_intro_point_free(intro
);
551 smartlist_del(ent
->parsed
->intro_nodes
, i
);
556 if (smartlist_len(ent
->parsed
->intro_nodes
) == 0) {
558 "No more intro points remain for %s. Re-fetching descriptor.",
559 escaped_safe_str(rend_query
->onion_address
));
560 /* Fetch both, v0 and v2 rend descriptors in parallel. Use whichever
561 * arrives first. Exception: When using client authorization, only
562 * fetch v2 descriptors.*/
563 rend_client_refetch_v2_renddesc(rend_query
);
564 if (rend_query
->auth_type
== REND_NO_AUTH
)
565 rend_client_refetch_renddesc(rend_query
->onion_address
);
567 /* move all pending streams back to renddesc_wait */
568 while ((conn
= connection_get_by_type_state_rendquery(CONN_TYPE_AP
,
569 AP_CONN_STATE_CIRCUIT_WAIT
,
570 rend_query
->onion_address
, -1))) {
571 conn
->state
= AP_CONN_STATE_RENDDESC_WAIT
;
576 log_info(LD_REND
,"%d options left for %s.",
577 smartlist_len(ent
->parsed
->intro_nodes
),
578 escaped_safe_str(rend_query
->onion_address
));
582 /** Called when we receive a RENDEZVOUS_ESTABLISHED cell; changes the state of
583 * the circuit to C_REND_READY.
586 rend_client_rendezvous_acked(origin_circuit_t
*circ
, const char *request
,
591 /* we just got an ack for our establish-rendezvous. switch purposes. */
592 if (circ
->_base
.purpose
!= CIRCUIT_PURPOSE_C_ESTABLISH_REND
) {
593 log_warn(LD_PROTOCOL
,"Got a rendezvous ack when we weren't expecting one. "
595 circuit_mark_for_close(TO_CIRCUIT(circ
), END_CIRC_REASON_TORPROTOCOL
);
598 log_info(LD_REND
,"Got rendezvous ack. This circuit is now ready for "
600 circ
->_base
.purpose
= CIRCUIT_PURPOSE_C_REND_READY
;
601 /* XXXX022 This is a pretty brute-force approach. It'd be better to
602 * attach only the connections that are waiting on this circuit, rather
603 * than trying to attach them all. See comments bug 743. */
604 /* If we already have the introduction circuit built, make sure we send
605 * the INTRODUCE cell _now_ */
606 connection_ap_attach_pending();
610 /** Bob sent us a rendezvous cell; join the circuits. */
612 rend_client_receive_rendezvous(origin_circuit_t
*circ
, const char *request
,
616 char keys
[DIGEST_LEN
+CPATH_KEY_MATERIAL_LEN
];
618 if ((circ
->_base
.purpose
!= CIRCUIT_PURPOSE_C_REND_READY
&&
619 circ
->_base
.purpose
!= CIRCUIT_PURPOSE_C_REND_READY_INTRO_ACKED
)
620 || !circ
->build_state
->pending_final_cpath
) {
621 log_warn(LD_PROTOCOL
,"Got rendezvous2 cell from hidden service, but not "
622 "expecting it. Closing.");
623 circuit_mark_for_close(TO_CIRCUIT(circ
), END_CIRC_REASON_TORPROTOCOL
);
627 if (request_len
!= DH_KEY_LEN
+DIGEST_LEN
) {
628 log_warn(LD_PROTOCOL
,"Incorrect length (%d) on RENDEZVOUS2 cell.",
633 log_info(LD_REND
,"Got RENDEZVOUS2 cell from hidden service.");
635 /* first DH_KEY_LEN bytes are g^y from bob. Finish the dh handshake...*/
636 tor_assert(circ
->build_state
);
637 tor_assert(circ
->build_state
->pending_final_cpath
);
638 hop
= circ
->build_state
->pending_final_cpath
;
639 tor_assert(hop
->dh_handshake_state
);
640 if (crypto_dh_compute_secret(hop
->dh_handshake_state
, request
, DH_KEY_LEN
,
641 keys
, DIGEST_LEN
+CPATH_KEY_MATERIAL_LEN
)<0) {
642 log_warn(LD_GENERAL
, "Couldn't complete DH handshake.");
645 /* ... and set up cpath. */
646 if (circuit_init_cpath_crypto(hop
, keys
+DIGEST_LEN
, 0)<0)
649 /* Check whether the digest is right... */
650 if (memcmp(keys
, request
+DH_KEY_LEN
, DIGEST_LEN
)) {
651 log_warn(LD_PROTOCOL
, "Incorrect digest of key material.");
655 crypto_dh_free(hop
->dh_handshake_state
);
656 hop
->dh_handshake_state
= NULL
;
658 /* All is well. Extend the circuit. */
659 circ
->_base
.purpose
= CIRCUIT_PURPOSE_C_REND_JOINED
;
660 hop
->state
= CPATH_STATE_OPEN
;
661 /* set the windows to default. these are the windows
662 * that alice thinks bob has.
664 hop
->package_window
= CIRCWINDOW_START
;
665 hop
->deliver_window
= CIRCWINDOW_START
;
667 onion_append_to_cpath(&circ
->cpath
, hop
);
668 circ
->build_state
->pending_final_cpath
= NULL
; /* prevent double-free */
669 /* XXXX022 This is a pretty brute-force approach. It'd be better to
670 * attach only the connections that are waiting on this circuit, rather
671 * than trying to attach them all. See comments bug 743. */
672 connection_ap_attach_pending();
675 circuit_mark_for_close(TO_CIRCUIT(circ
), END_CIRC_REASON_TORPROTOCOL
);
679 /** Find all the apconns in state AP_CONN_STATE_RENDDESC_WAIT that
680 * are waiting on query. If there's a working cache entry here
681 * with at least one intro point, move them to the next state. If
682 * <b>rend_version</b> is non-negative, fail connections that have
683 * requested <b>query</b> unless there are still descriptor fetch
684 * requests in progress for other descriptor versions than
685 * <b>rend_version</b>.
688 rend_client_desc_trynow(const char *query
, int rend_version
)
690 edge_connection_t
*conn
;
691 rend_cache_entry_t
*entry
;
692 time_t now
= time(NULL
);
694 smartlist_t
*conns
= get_connection_array();
695 SMARTLIST_FOREACH(conns
, connection_t
*, _conn
,
697 if (_conn
->type
!= CONN_TYPE_AP
||
698 _conn
->state
!= AP_CONN_STATE_RENDDESC_WAIT
||
699 _conn
->marked_for_close
)
701 conn
= TO_EDGE_CONN(_conn
);
702 if (!conn
->rend_data
)
704 if (rend_cmp_service_ids(query
, conn
->rend_data
->onion_address
))
706 assert_connection_ok(TO_CONN(conn
), now
);
707 if (rend_cache_lookup_entry(conn
->rend_data
->onion_address
, -1,
709 smartlist_len(entry
->parsed
->intro_nodes
) > 0) {
710 /* either this fetch worked, or it failed but there was a
711 * valid entry from before which we should reuse */
712 log_info(LD_REND
,"Rend desc is usable. Launching circuits.");
713 conn
->_base
.state
= AP_CONN_STATE_CIRCUIT_WAIT
;
715 /* restart their timeout values, so they get a fair shake at
716 * connecting to the hidden service. */
717 conn
->_base
.timestamp_created
= now
;
718 conn
->_base
.timestamp_lastread
= now
;
719 conn
->_base
.timestamp_lastwritten
= now
;
721 if (connection_ap_handshake_attach_circuit(conn
) < 0) {
722 /* it will never work */
723 log_warn(LD_REND
,"Rendezvous attempt failed. Closing.");
724 if (!conn
->_base
.marked_for_close
)
725 connection_mark_unattached_ap(conn
, END_STREAM_REASON_CANT_ATTACH
);
727 } else { /* 404, or fetch didn't get that far */
728 /* Unless there are requests for another descriptor version pending,
729 * close the connection. */
730 if (rend_version
>= 0 &&
731 !connection_get_by_type_state_rendquery(CONN_TYPE_DIR
, 0, query
,
732 rend_version
== 0 ? 2 : 0)) {
733 log_notice(LD_REND
,"Closing stream for '%s.onion': hidden service is "
734 "unavailable (try again later).", safe_str(query
));
735 connection_mark_unattached_ap(conn
, END_STREAM_REASON_RESOLVEFAILED
);
741 /** Return a newly allocated extend_info_t* for a randomly chosen introduction
742 * point for the named hidden service. Return NULL if all introduction points
743 * have been tried and failed.
746 rend_client_get_random_intro(const rend_data_t
*rend_query
)
749 rend_cache_entry_t
*entry
;
750 rend_intro_point_t
*intro
;
751 routerinfo_t
*router
;
753 if (rend_cache_lookup_entry(rend_query
->onion_address
, -1, &entry
) < 1) {
755 "Query '%s' didn't have valid rend desc in cache. Failing.",
756 safe_str(rend_query
->onion_address
));
761 if (smartlist_len(entry
->parsed
->intro_nodes
) == 0)
764 i
= crypto_rand_int(smartlist_len(entry
->parsed
->intro_nodes
));
765 intro
= smartlist_get(entry
->parsed
->intro_nodes
, i
);
766 /* Do we need to look up the router or is the extend info complete? */
767 if (!intro
->extend_info
->onion_key
) {
768 router
= router_get_by_nickname(intro
->extend_info
->nickname
, 0);
770 log_info(LD_REND
, "Unknown router with nickname '%s'; trying another.",
771 intro
->extend_info
->nickname
);
772 rend_intro_point_free(intro
);
773 smartlist_del(entry
->parsed
->intro_nodes
, i
);
776 extend_info_free(intro
->extend_info
);
777 intro
->extend_info
= extend_info_from_router(router
);
779 return extend_info_dup(intro
->extend_info
);
782 /** Client-side authorizations for hidden services; map of onion address to
783 * rend_service_authorization_t*. */
784 static strmap_t
*auth_hid_servs
= NULL
;
786 /** Look up the client-side authorization for the hidden service with
787 * <b>onion_address</b>. Return NULL if no authorization is available for
789 rend_service_authorization_t
*
790 rend_client_lookup_service_authorization(const char *onion_address
)
792 tor_assert(onion_address
);
793 if (!auth_hid_servs
) return NULL
;
794 return strmap_get(auth_hid_servs
, onion_address
);
797 /** Helper: Free storage held by rend_service_authorization_t. */
799 rend_service_authorization_free(rend_service_authorization_t
*auth
)
804 /** Helper for strmap_free. */
806 rend_service_authorization_strmap_item_free(void *service_auth
)
808 rend_service_authorization_free(service_auth
);
811 /** Release all the storage held in auth_hid_servs.
814 rend_service_authorization_free_all(void)
816 if (!auth_hid_servs
) {
819 strmap_free(auth_hid_servs
, rend_service_authorization_strmap_item_free
);
820 auth_hid_servs
= NULL
;
823 /** Parse <b>config_line</b> as a client-side authorization for a hidden
824 * service and add it to the local map of hidden service authorizations.
825 * Return 0 for success and -1 for failure. */
827 rend_parse_service_authorization(or_options_t
*options
, int validate_only
)
831 strmap_t
*parsed
= strmap_new();
832 smartlist_t
*sl
= smartlist_create();
833 rend_service_authorization_t
*auth
= NULL
;
835 for (line
= options
->HidServAuth
; line
; line
= line
->next
) {
836 char *onion_address
, *descriptor_cookie
;
837 char descriptor_cookie_tmp
[REND_DESC_COOKIE_LEN
+2];
838 char descriptor_cookie_base64ext
[REND_DESC_COOKIE_LEN_BASE64
+2+1];
839 int auth_type_val
= 0;
841 SMARTLIST_FOREACH(sl
, char *, c
, tor_free(c
););
843 smartlist_split_string(sl
, line
->value
, " ",
844 SPLIT_SKIP_SPACE
|SPLIT_IGNORE_BLANK
, 3);
845 if (smartlist_len(sl
) < 2) {
846 log_warn(LD_CONFIG
, "Configuration line does not consist of "
847 "\"onion-address authorization-cookie [service-name]\": "
848 "'%s'", line
->value
);
851 auth
= tor_malloc_zero(sizeof(rend_service_authorization_t
));
852 /* Parse onion address. */
853 onion_address
= smartlist_get(sl
, 0);
854 if (strlen(onion_address
) != REND_SERVICE_ADDRESS_LEN
||
855 strcmpend(onion_address
, ".onion")) {
856 log_warn(LD_CONFIG
, "Onion address has wrong format: '%s'",
860 strlcpy(auth
->onion_address
, onion_address
, REND_SERVICE_ID_LEN_BASE32
+1);
861 if (!rend_valid_service_id(auth
->onion_address
)) {
862 log_warn(LD_CONFIG
, "Onion address has wrong format: '%s'",
866 /* Parse descriptor cookie. */
867 descriptor_cookie
= smartlist_get(sl
, 1);
868 if (strlen(descriptor_cookie
) != REND_DESC_COOKIE_LEN_BASE64
) {
869 log_warn(LD_CONFIG
, "Authorization cookie has wrong length: '%s'",
873 /* Add trailing zero bytes (AA) to make base64-decoding happy. */
874 tor_snprintf(descriptor_cookie_base64ext
,
875 REND_DESC_COOKIE_LEN_BASE64
+2+1,
876 "%sAA", descriptor_cookie
);
877 if (base64_decode(descriptor_cookie_tmp
, sizeof(descriptor_cookie_tmp
),
878 descriptor_cookie_base64ext
,
879 strlen(descriptor_cookie_base64ext
)) < 0) {
880 log_warn(LD_CONFIG
, "Decoding authorization cookie failed: '%s'",
884 auth_type_val
= (descriptor_cookie_tmp
[16] >> 4) + 1;
885 if (auth_type_val
< 1 || auth_type_val
> 2) {
886 log_warn(LD_CONFIG
, "Authorization cookie has unknown authorization "
890 auth
->auth_type
= auth_type_val
== 1 ? REND_BASIC_AUTH
: REND_STEALTH_AUTH
;
891 memcpy(auth
->descriptor_cookie
, descriptor_cookie_tmp
,
892 REND_DESC_COOKIE_LEN
);
893 if (strmap_get(parsed
, auth
->onion_address
)) {
894 log_warn(LD_CONFIG
, "Duplicate authorization for the same hidden "
898 strmap_set(parsed
, auth
->onion_address
, auth
);
907 rend_service_authorization_free(auth
);
908 SMARTLIST_FOREACH(sl
, char *, c
, tor_free(c
););
910 if (!validate_only
&& res
== 0) {
911 rend_service_authorization_free_all();
912 auth_hid_servs
= parsed
;
914 strmap_free(parsed
, rend_service_authorization_strmap_item_free
);