networkstatus.c 93 KB

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  1. /* Copyright (c) 2001 Matej Pfajfar.
  2. * Copyright (c) 2001-2004, Roger Dingledine.
  3. * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
  4. * Copyright (c) 2007-2017, The Tor Project, Inc. */
  5. /* See LICENSE for licensing information */
  6. /**
  7. * \file networkstatus.c
  8. * \brief Functions and structures for handling networkstatus documents as a
  9. * client or as a directory cache.
  10. *
  11. * A consensus networkstatus object is created by the directory
  12. * authorities. It authenticates a set of network parameters--most
  13. * importantly, the list of all the relays in the network. This list
  14. * of relays is represented as an array of routerstatus_t objects.
  15. *
  16. * There are currently two flavors of consensus. With the older "NS"
  17. * flavor, each relay is associated with a digest of its router
  18. * descriptor. Tor instances that use this consensus keep the list of
  19. * router descriptors as routerinfo_t objects stored and managed in
  20. * routerlist.c. With the newer "microdesc" flavor, each relay is
  21. * associated with a digest of the microdescriptor that the authorities
  22. * made for it. These are stored and managed in microdesc.c. Information
  23. * about the router is divided between the the networkstatus and the
  24. * microdescriptor according to the general rule that microdescriptors
  25. * should hold information that changes much less frequently than the
  26. * information in the networkstatus.
  27. *
  28. * Modern clients use microdescriptor networkstatuses. Directory caches
  29. * need to keep both kinds of networkstatus document, so they can serve them.
  30. *
  31. * This module manages fetching, holding, storing, updating, and
  32. * validating networkstatus objects. The download-and-validate process
  33. * is slightly complicated by the fact that the keys you need to
  34. * validate a consensus are stored in the authority certificates, which
  35. * you might not have yet when you download the consensus.
  36. */
  37. #define NETWORKSTATUS_PRIVATE
  38. #include "or.h"
  39. #include "bridges.h"
  40. #include "channel.h"
  41. #include "circuitmux.h"
  42. #include "circuitmux_ewma.h"
  43. #include "circuitstats.h"
  44. #include "config.h"
  45. #include "connection.h"
  46. #include "connection_or.h"
  47. #include "consdiffmgr.h"
  48. #include "control.h"
  49. #include "directory.h"
  50. #include "dirserv.h"
  51. #include "dirvote.h"
  52. #include "entrynodes.h"
  53. #include "hibernate.h"
  54. #include "main.h"
  55. #include "microdesc.h"
  56. #include "networkstatus.h"
  57. #include "nodelist.h"
  58. #include "protover.h"
  59. #include "relay.h"
  60. #include "router.h"
  61. #include "routerlist.h"
  62. #include "routerparse.h"
  63. #include "scheduler.h"
  64. #include "shared_random.h"
  65. #include "transports.h"
  66. #include "torcert.h"
  67. #include "channelpadding.h"
  68. /** Most recently received and validated v3 "ns"-flavored consensus network
  69. * status. */
  70. STATIC networkstatus_t *current_ns_consensus = NULL;
  71. /** Most recently received and validated v3 "microdesc"-flavored consensus
  72. * network status. */
  73. STATIC networkstatus_t *current_md_consensus = NULL;
  74. /** A v3 consensus networkstatus that we've received, but which we don't
  75. * have enough certificates to be happy about. */
  76. typedef struct consensus_waiting_for_certs_t {
  77. /** The consensus itself. */
  78. networkstatus_t *consensus;
  79. /** The encoded version of the consensus, nul-terminated. */
  80. char *body;
  81. /** When did we set the current value of consensus_waiting_for_certs? If
  82. * this is too recent, we shouldn't try to fetch a new consensus for a
  83. * little while, to give ourselves time to get certificates for this one. */
  84. time_t set_at;
  85. /** Set to 1 if we've been holding on to it for so long we should maybe
  86. * treat it as being bad. */
  87. int dl_failed;
  88. } consensus_waiting_for_certs_t;
  89. /** An array, for each flavor of consensus we might want, of consensuses that
  90. * we have downloaded, but which we cannot verify due to having insufficient
  91. * authority certificates. */
  92. static consensus_waiting_for_certs_t
  93. consensus_waiting_for_certs[N_CONSENSUS_FLAVORS];
  94. /** A time before which we shouldn't try to replace the current consensus:
  95. * this will be at some point after the next consensus becomes valid, but
  96. * before the current consensus becomes invalid. */
  97. static time_t time_to_download_next_consensus[N_CONSENSUS_FLAVORS];
  98. /** Download status for the current consensus networkstatus. */
  99. static download_status_t consensus_dl_status[N_CONSENSUS_FLAVORS] =
  100. {
  101. { 0, 0, 0, DL_SCHED_CONSENSUS, DL_WANT_ANY_DIRSERVER,
  102. DL_SCHED_INCREMENT_FAILURE, DL_SCHED_RANDOM_EXPONENTIAL, 0, 0 },
  103. { 0, 0, 0, DL_SCHED_CONSENSUS, DL_WANT_ANY_DIRSERVER,
  104. DL_SCHED_INCREMENT_FAILURE, DL_SCHED_RANDOM_EXPONENTIAL, 0, 0 },
  105. };
  106. #define N_CONSENSUS_BOOTSTRAP_SCHEDULES 2
  107. #define CONSENSUS_BOOTSTRAP_SOURCE_AUTHORITY 0
  108. #define CONSENSUS_BOOTSTRAP_SOURCE_ANY_DIRSERVER 1
  109. /* Using DL_SCHED_INCREMENT_ATTEMPT on these schedules means that
  110. * download_status_increment_failure won't increment these entries.
  111. * However, any bootstrap connection failures that occur after we have
  112. * a valid consensus will count against the failure counts on the non-bootstrap
  113. * schedules. There should only be one of these, as all the others will have
  114. * been cancelled. (This doesn't seem to be a significant issue.) */
  115. static download_status_t
  116. consensus_bootstrap_dl_status[N_CONSENSUS_BOOTSTRAP_SCHEDULES] =
  117. {
  118. { 0, 0, 0, DL_SCHED_CONSENSUS, DL_WANT_AUTHORITY,
  119. DL_SCHED_INCREMENT_ATTEMPT, DL_SCHED_RANDOM_EXPONENTIAL, 0, 0 },
  120. /* During bootstrap, DL_WANT_ANY_DIRSERVER means "use fallbacks". */
  121. { 0, 0, 0, DL_SCHED_CONSENSUS, DL_WANT_ANY_DIRSERVER,
  122. DL_SCHED_INCREMENT_ATTEMPT, DL_SCHED_RANDOM_EXPONENTIAL, 0, 0 },
  123. };
  124. /** True iff we have logged a warning about this OR's version being older than
  125. * listed by the authorities. */
  126. static int have_warned_about_old_version = 0;
  127. /** True iff we have logged a warning about this OR's version being newer than
  128. * listed by the authorities. */
  129. static int have_warned_about_new_version = 0;
  130. static void update_consensus_bootstrap_multiple_downloads(
  131. time_t now,
  132. const or_options_t *options);
  133. static int networkstatus_check_required_protocols(const networkstatus_t *ns,
  134. int client_mode,
  135. char **warning_out);
  136. /** Forget that we've warned about anything networkstatus-related, so we will
  137. * give fresh warnings if the same behavior happens again. */
  138. void
  139. networkstatus_reset_warnings(void)
  140. {
  141. SMARTLIST_FOREACH(nodelist_get_list(), node_t *, node,
  142. node->name_lookup_warned = 0);
  143. have_warned_about_old_version = 0;
  144. have_warned_about_new_version = 0;
  145. }
  146. /** Reset the descriptor download failure count on all networkstatus docs, so
  147. * that we can retry any long-failed documents immediately.
  148. */
  149. void
  150. networkstatus_reset_download_failures(void)
  151. {
  152. int i;
  153. log_debug(LD_GENERAL,
  154. "In networkstatus_reset_download_failures()");
  155. for (i=0; i < N_CONSENSUS_FLAVORS; ++i)
  156. download_status_reset(&consensus_dl_status[i]);
  157. for (i=0; i < N_CONSENSUS_BOOTSTRAP_SCHEDULES; ++i)
  158. download_status_reset(&consensus_bootstrap_dl_status[i]);
  159. }
  160. /**
  161. * Read and and return the cached consensus of type <b>flavorname</b>. If
  162. * <b>unverified</b> is false, get the one we haven't verified. Return NULL if
  163. * the file isn't there. */
  164. static char *
  165. networkstatus_read_cached_consensus_impl(int flav,
  166. const char *flavorname,
  167. int unverified_consensus)
  168. {
  169. char buf[128];
  170. const char *prefix;
  171. if (unverified_consensus) {
  172. prefix = "unverified";
  173. } else {
  174. prefix = "cached";
  175. }
  176. if (flav == FLAV_NS) {
  177. tor_snprintf(buf, sizeof(buf), "%s-consensus", prefix);
  178. } else {
  179. tor_snprintf(buf, sizeof(buf), "%s-%s-consensus", prefix, flavorname);
  180. }
  181. char *filename = get_datadir_fname(buf);
  182. char *result = read_file_to_str(filename, RFTS_IGNORE_MISSING, NULL);
  183. tor_free(filename);
  184. return result;
  185. }
  186. /** Return a new string containing the current cached consensus of flavor
  187. * <b>flavorname</b>. */
  188. char *
  189. networkstatus_read_cached_consensus(const char *flavorname)
  190. {
  191. int flav = networkstatus_parse_flavor_name(flavorname);
  192. if (flav < 0)
  193. return NULL;
  194. return networkstatus_read_cached_consensus_impl(flav, flavorname, 0);
  195. }
  196. /** Read every cached v3 consensus networkstatus from the disk. */
  197. int
  198. router_reload_consensus_networkstatus(void)
  199. {
  200. const unsigned int flags = NSSET_FROM_CACHE | NSSET_DONT_DOWNLOAD_CERTS;
  201. int flav;
  202. /* FFFF Suppress warnings if cached consensus is bad? */
  203. for (flav = 0; flav < N_CONSENSUS_FLAVORS; ++flav) {
  204. const char *flavor = networkstatus_get_flavor_name(flav);
  205. char *s = networkstatus_read_cached_consensus_impl(flav, flavor, 0);
  206. if (s) {
  207. if (networkstatus_set_current_consensus(s, flavor, flags, NULL) < -1) {
  208. log_warn(LD_FS, "Couldn't load consensus %s networkstatus from cache",
  209. flavor);
  210. }
  211. tor_free(s);
  212. }
  213. s = networkstatus_read_cached_consensus_impl(flav, flavor, 1);
  214. if (s) {
  215. if (networkstatus_set_current_consensus(s, flavor,
  216. flags|NSSET_WAS_WAITING_FOR_CERTS,
  217. NULL)) {
  218. log_info(LD_FS, "Couldn't load unverified consensus %s networkstatus "
  219. "from cache", flavor);
  220. }
  221. tor_free(s);
  222. }
  223. }
  224. update_certificate_downloads(time(NULL));
  225. routers_update_all_from_networkstatus(time(NULL), 3);
  226. update_microdescs_from_networkstatus(time(NULL));
  227. return 0;
  228. }
  229. /** Free all storage held by the vote_routerstatus object <b>rs</b>. */
  230. void
  231. vote_routerstatus_free(vote_routerstatus_t *rs)
  232. {
  233. vote_microdesc_hash_t *h, *next;
  234. if (!rs)
  235. return;
  236. tor_free(rs->version);
  237. tor_free(rs->protocols);
  238. tor_free(rs->status.exitsummary);
  239. for (h = rs->microdesc; h; h = next) {
  240. tor_free(h->microdesc_hash_line);
  241. next = h->next;
  242. tor_free(h);
  243. }
  244. tor_free(rs);
  245. }
  246. /** Free all storage held by the routerstatus object <b>rs</b>. */
  247. void
  248. routerstatus_free(routerstatus_t *rs)
  249. {
  250. if (!rs)
  251. return;
  252. tor_free(rs->exitsummary);
  253. tor_free(rs);
  254. }
  255. /** Free all storage held in <b>sig</b> */
  256. void
  257. document_signature_free(document_signature_t *sig)
  258. {
  259. tor_free(sig->signature);
  260. tor_free(sig);
  261. }
  262. /** Return a newly allocated copy of <b>sig</b> */
  263. document_signature_t *
  264. document_signature_dup(const document_signature_t *sig)
  265. {
  266. document_signature_t *r = tor_memdup(sig, sizeof(document_signature_t));
  267. if (r->signature)
  268. r->signature = tor_memdup(sig->signature, sig->signature_len);
  269. return r;
  270. }
  271. /** Free all storage held in <b>ns</b>. */
  272. void
  273. networkstatus_vote_free(networkstatus_t *ns)
  274. {
  275. if (!ns)
  276. return;
  277. tor_free(ns->client_versions);
  278. tor_free(ns->server_versions);
  279. tor_free(ns->recommended_client_protocols);
  280. tor_free(ns->recommended_relay_protocols);
  281. tor_free(ns->required_client_protocols);
  282. tor_free(ns->required_relay_protocols);
  283. if (ns->known_flags) {
  284. SMARTLIST_FOREACH(ns->known_flags, char *, c, tor_free(c));
  285. smartlist_free(ns->known_flags);
  286. }
  287. if (ns->weight_params) {
  288. SMARTLIST_FOREACH(ns->weight_params, char *, c, tor_free(c));
  289. smartlist_free(ns->weight_params);
  290. }
  291. if (ns->net_params) {
  292. SMARTLIST_FOREACH(ns->net_params, char *, c, tor_free(c));
  293. smartlist_free(ns->net_params);
  294. }
  295. if (ns->supported_methods) {
  296. SMARTLIST_FOREACH(ns->supported_methods, char *, c, tor_free(c));
  297. smartlist_free(ns->supported_methods);
  298. }
  299. if (ns->package_lines) {
  300. SMARTLIST_FOREACH(ns->package_lines, char *, c, tor_free(c));
  301. smartlist_free(ns->package_lines);
  302. }
  303. if (ns->voters) {
  304. SMARTLIST_FOREACH_BEGIN(ns->voters, networkstatus_voter_info_t *, voter) {
  305. tor_free(voter->nickname);
  306. tor_free(voter->address);
  307. tor_free(voter->contact);
  308. if (voter->sigs) {
  309. SMARTLIST_FOREACH(voter->sigs, document_signature_t *, sig,
  310. document_signature_free(sig));
  311. smartlist_free(voter->sigs);
  312. }
  313. tor_free(voter);
  314. } SMARTLIST_FOREACH_END(voter);
  315. smartlist_free(ns->voters);
  316. }
  317. authority_cert_free(ns->cert);
  318. if (ns->routerstatus_list) {
  319. if (ns->type == NS_TYPE_VOTE || ns->type == NS_TYPE_OPINION) {
  320. SMARTLIST_FOREACH(ns->routerstatus_list, vote_routerstatus_t *, rs,
  321. vote_routerstatus_free(rs));
  322. } else {
  323. SMARTLIST_FOREACH(ns->routerstatus_list, routerstatus_t *, rs,
  324. routerstatus_free(rs));
  325. }
  326. smartlist_free(ns->routerstatus_list);
  327. }
  328. digestmap_free(ns->desc_digest_map, NULL);
  329. if (ns->sr_info.commits) {
  330. SMARTLIST_FOREACH(ns->sr_info.commits, sr_commit_t *, c,
  331. sr_commit_free(c));
  332. smartlist_free(ns->sr_info.commits);
  333. }
  334. tor_free(ns->sr_info.previous_srv);
  335. tor_free(ns->sr_info.current_srv);
  336. memwipe(ns, 11, sizeof(*ns));
  337. tor_free(ns);
  338. }
  339. /** Return the voter info from <b>vote</b> for the voter whose identity digest
  340. * is <b>identity</b>, or NULL if no such voter is associated with
  341. * <b>vote</b>. */
  342. networkstatus_voter_info_t *
  343. networkstatus_get_voter_by_id(networkstatus_t *vote,
  344. const char *identity)
  345. {
  346. if (!vote || !vote->voters)
  347. return NULL;
  348. SMARTLIST_FOREACH(vote->voters, networkstatus_voter_info_t *, voter,
  349. if (fast_memeq(voter->identity_digest, identity, DIGEST_LEN))
  350. return voter);
  351. return NULL;
  352. }
  353. /** Check whether the signature <b>sig</b> is correctly signed with the
  354. * signing key in <b>cert</b>. Return -1 if <b>cert</b> doesn't match the
  355. * signing key; otherwise set the good_signature or bad_signature flag on
  356. * <b>voter</b>, and return 0. */
  357. int
  358. networkstatus_check_document_signature(const networkstatus_t *consensus,
  359. document_signature_t *sig,
  360. const authority_cert_t *cert)
  361. {
  362. char key_digest[DIGEST_LEN];
  363. const int dlen = sig->alg == DIGEST_SHA1 ? DIGEST_LEN : DIGEST256_LEN;
  364. char *signed_digest;
  365. size_t signed_digest_len;
  366. if (crypto_pk_get_digest(cert->signing_key, key_digest)<0)
  367. return -1;
  368. if (tor_memneq(sig->signing_key_digest, key_digest, DIGEST_LEN) ||
  369. tor_memneq(sig->identity_digest, cert->cache_info.identity_digest,
  370. DIGEST_LEN))
  371. return -1;
  372. if (authority_cert_is_blacklisted(cert)) {
  373. /* We implement blacklisting for authority signing keys by treating
  374. * all their signatures as always bad. That way we don't get into
  375. * crazy loops of dropping and re-fetching signatures. */
  376. log_warn(LD_DIR, "Ignoring a consensus signature made with deprecated"
  377. " signing key %s",
  378. hex_str(cert->signing_key_digest, DIGEST_LEN));
  379. sig->bad_signature = 1;
  380. return 0;
  381. }
  382. signed_digest_len = crypto_pk_keysize(cert->signing_key);
  383. signed_digest = tor_malloc(signed_digest_len);
  384. if (crypto_pk_public_checksig(cert->signing_key,
  385. signed_digest,
  386. signed_digest_len,
  387. sig->signature,
  388. sig->signature_len) < dlen ||
  389. tor_memneq(signed_digest, consensus->digests.d[sig->alg], dlen)) {
  390. log_warn(LD_DIR, "Got a bad signature on a networkstatus vote");
  391. sig->bad_signature = 1;
  392. } else {
  393. sig->good_signature = 1;
  394. }
  395. tor_free(signed_digest);
  396. return 0;
  397. }
  398. /** Given a v3 networkstatus consensus in <b>consensus</b>, check every
  399. * as-yet-unchecked signature on <b>consensus</b>. Return 1 if there is a
  400. * signature from every recognized authority on it, 0 if there are
  401. * enough good signatures from recognized authorities on it, -1 if we might
  402. * get enough good signatures by fetching missing certificates, and -2
  403. * otherwise. Log messages at INFO or WARN: if <b>warn</b> is over 1, warn
  404. * about every problem; if warn is at least 1, warn only if we can't get
  405. * enough signatures; if warn is negative, log nothing at all. */
  406. int
  407. networkstatus_check_consensus_signature(networkstatus_t *consensus,
  408. int warn)
  409. {
  410. int n_good = 0;
  411. int n_missing_key = 0, n_dl_failed_key = 0;
  412. int n_bad = 0;
  413. int n_unknown = 0;
  414. int n_no_signature = 0;
  415. int n_v3_authorities = get_n_authorities(V3_DIRINFO);
  416. int n_required = n_v3_authorities/2 + 1;
  417. smartlist_t *list_good = smartlist_new();
  418. smartlist_t *list_no_signature = smartlist_new();
  419. smartlist_t *need_certs_from = smartlist_new();
  420. smartlist_t *unrecognized = smartlist_new();
  421. smartlist_t *missing_authorities = smartlist_new();
  422. int severity;
  423. time_t now = time(NULL);
  424. tor_assert(consensus->type == NS_TYPE_CONSENSUS);
  425. SMARTLIST_FOREACH_BEGIN(consensus->voters, networkstatus_voter_info_t *,
  426. voter) {
  427. int good_here = 0;
  428. int bad_here = 0;
  429. int unknown_here = 0;
  430. int missing_key_here = 0, dl_failed_key_here = 0;
  431. SMARTLIST_FOREACH_BEGIN(voter->sigs, document_signature_t *, sig) {
  432. if (!sig->good_signature && !sig->bad_signature &&
  433. sig->signature) {
  434. /* we can try to check the signature. */
  435. int is_v3_auth = trusteddirserver_get_by_v3_auth_digest(
  436. sig->identity_digest) != NULL;
  437. authority_cert_t *cert =
  438. authority_cert_get_by_digests(sig->identity_digest,
  439. sig->signing_key_digest);
  440. tor_assert(tor_memeq(sig->identity_digest, voter->identity_digest,
  441. DIGEST_LEN));
  442. if (!is_v3_auth) {
  443. smartlist_add(unrecognized, voter);
  444. ++unknown_here;
  445. continue;
  446. } else if (!cert || cert->expires < now) {
  447. smartlist_add(need_certs_from, voter);
  448. ++missing_key_here;
  449. if (authority_cert_dl_looks_uncertain(sig->identity_digest))
  450. ++dl_failed_key_here;
  451. continue;
  452. }
  453. if (networkstatus_check_document_signature(consensus, sig, cert) < 0) {
  454. smartlist_add(need_certs_from, voter);
  455. ++missing_key_here;
  456. if (authority_cert_dl_looks_uncertain(sig->identity_digest))
  457. ++dl_failed_key_here;
  458. continue;
  459. }
  460. }
  461. if (sig->good_signature)
  462. ++good_here;
  463. else if (sig->bad_signature)
  464. ++bad_here;
  465. } SMARTLIST_FOREACH_END(sig);
  466. if (good_here) {
  467. ++n_good;
  468. smartlist_add(list_good, voter->nickname);
  469. } else if (bad_here) {
  470. ++n_bad;
  471. } else if (missing_key_here) {
  472. ++n_missing_key;
  473. if (dl_failed_key_here)
  474. ++n_dl_failed_key;
  475. } else if (unknown_here) {
  476. ++n_unknown;
  477. } else {
  478. ++n_no_signature;
  479. smartlist_add(list_no_signature, voter->nickname);
  480. }
  481. } SMARTLIST_FOREACH_END(voter);
  482. /* Now see whether we're missing any voters entirely. */
  483. SMARTLIST_FOREACH(router_get_trusted_dir_servers(),
  484. dir_server_t *, ds,
  485. {
  486. if ((ds->type & V3_DIRINFO) &&
  487. !networkstatus_get_voter_by_id(consensus, ds->v3_identity_digest))
  488. smartlist_add(missing_authorities, ds);
  489. });
  490. if (warn > 1 || (warn >= 0 &&
  491. (n_good + n_missing_key - n_dl_failed_key < n_required))) {
  492. severity = LOG_WARN;
  493. } else {
  494. severity = LOG_INFO;
  495. }
  496. if (warn >= 0) {
  497. SMARTLIST_FOREACH(unrecognized, networkstatus_voter_info_t *, voter,
  498. {
  499. tor_log(severity, LD_DIR, "Consensus includes unrecognized authority "
  500. "'%s' at %s:%d (contact %s; identity %s)",
  501. voter->nickname, voter->address, (int)voter->dir_port,
  502. voter->contact?voter->contact:"n/a",
  503. hex_str(voter->identity_digest, DIGEST_LEN));
  504. });
  505. SMARTLIST_FOREACH(need_certs_from, networkstatus_voter_info_t *, voter,
  506. {
  507. tor_log(severity, LD_DIR, "Looks like we need to download a new "
  508. "certificate from authority '%s' at %s:%d (contact %s; "
  509. "identity %s)",
  510. voter->nickname, voter->address, (int)voter->dir_port,
  511. voter->contact?voter->contact:"n/a",
  512. hex_str(voter->identity_digest, DIGEST_LEN));
  513. });
  514. SMARTLIST_FOREACH(missing_authorities, dir_server_t *, ds,
  515. {
  516. tor_log(severity, LD_DIR, "Consensus does not include configured "
  517. "authority '%s' at %s:%d (identity %s)",
  518. ds->nickname, ds->address, (int)ds->dir_port,
  519. hex_str(ds->v3_identity_digest, DIGEST_LEN));
  520. });
  521. {
  522. char *joined;
  523. smartlist_t *sl = smartlist_new();
  524. char *tmp = smartlist_join_strings(list_good, " ", 0, NULL);
  525. smartlist_add_asprintf(sl,
  526. "A consensus needs %d good signatures from recognized "
  527. "authorities for us to accept it. This one has %d (%s).",
  528. n_required, n_good, tmp);
  529. tor_free(tmp);
  530. if (n_no_signature) {
  531. tmp = smartlist_join_strings(list_no_signature, " ", 0, NULL);
  532. smartlist_add_asprintf(sl,
  533. "%d (%s) of the authorities we know didn't sign it.",
  534. n_no_signature, tmp);
  535. tor_free(tmp);
  536. }
  537. if (n_unknown) {
  538. smartlist_add_asprintf(sl,
  539. "It has %d signatures from authorities we don't "
  540. "recognize.", n_unknown);
  541. }
  542. if (n_bad) {
  543. smartlist_add_asprintf(sl, "%d of the signatures on it didn't verify "
  544. "correctly.", n_bad);
  545. }
  546. if (n_missing_key) {
  547. smartlist_add_asprintf(sl,
  548. "We were unable to check %d of the signatures, "
  549. "because we were missing the keys.", n_missing_key);
  550. }
  551. joined = smartlist_join_strings(sl, " ", 0, NULL);
  552. tor_log(severity, LD_DIR, "%s", joined);
  553. tor_free(joined);
  554. SMARTLIST_FOREACH(sl, char *, c, tor_free(c));
  555. smartlist_free(sl);
  556. }
  557. }
  558. smartlist_free(list_good);
  559. smartlist_free(list_no_signature);
  560. smartlist_free(unrecognized);
  561. smartlist_free(need_certs_from);
  562. smartlist_free(missing_authorities);
  563. if (n_good == n_v3_authorities)
  564. return 1;
  565. else if (n_good >= n_required)
  566. return 0;
  567. else if (n_good + n_missing_key >= n_required)
  568. return -1;
  569. else
  570. return -2;
  571. }
  572. /** How far in the future do we allow a network-status to get before removing
  573. * it? (seconds) */
  574. #define NETWORKSTATUS_ALLOW_SKEW (24*60*60)
  575. /** Helper for bsearching a list of routerstatus_t pointers: compare a
  576. * digest in the key to the identity digest of a routerstatus_t. */
  577. int
  578. compare_digest_to_routerstatus_entry(const void *_key, const void **_member)
  579. {
  580. const char *key = _key;
  581. const routerstatus_t *rs = *_member;
  582. return tor_memcmp(key, rs->identity_digest, DIGEST_LEN);
  583. }
  584. /** Helper for bsearching a list of routerstatus_t pointers: compare a
  585. * digest in the key to the identity digest of a routerstatus_t. */
  586. int
  587. compare_digest_to_vote_routerstatus_entry(const void *_key,
  588. const void **_member)
  589. {
  590. const char *key = _key;
  591. const vote_routerstatus_t *vrs = *_member;
  592. return tor_memcmp(key, vrs->status.identity_digest, DIGEST_LEN);
  593. }
  594. /** As networkstatus_find_entry, but do not return a const pointer */
  595. routerstatus_t *
  596. networkstatus_vote_find_mutable_entry(networkstatus_t *ns, const char *digest)
  597. {
  598. return smartlist_bsearch(ns->routerstatus_list, digest,
  599. compare_digest_to_routerstatus_entry);
  600. }
  601. /** Return the entry in <b>ns</b> for the identity digest <b>digest</b>, or
  602. * NULL if none was found. */
  603. const routerstatus_t *
  604. networkstatus_vote_find_entry(networkstatus_t *ns, const char *digest)
  605. {
  606. return networkstatus_vote_find_mutable_entry(ns, digest);
  607. }
  608. /*XXXX MOVE make this static once functions are moved into this file. */
  609. /** Search the routerstatuses in <b>ns</b> for one whose identity digest is
  610. * <b>digest</b>. Return value and set *<b>found_out</b> as for
  611. * smartlist_bsearch_idx(). */
  612. int
  613. networkstatus_vote_find_entry_idx(networkstatus_t *ns,
  614. const char *digest, int *found_out)
  615. {
  616. return smartlist_bsearch_idx(ns->routerstatus_list, digest,
  617. compare_digest_to_routerstatus_entry,
  618. found_out);
  619. }
  620. /** As router_get_consensus_status_by_descriptor_digest, but does not return
  621. * a const pointer. */
  622. MOCK_IMPL(routerstatus_t *,
  623. router_get_mutable_consensus_status_by_descriptor_digest,(
  624. networkstatus_t *consensus,
  625. const char *digest))
  626. {
  627. if (!consensus)
  628. consensus = networkstatus_get_latest_consensus();
  629. if (!consensus)
  630. return NULL;
  631. if (!consensus->desc_digest_map) {
  632. digestmap_t *m = consensus->desc_digest_map = digestmap_new();
  633. SMARTLIST_FOREACH(consensus->routerstatus_list,
  634. routerstatus_t *, rs,
  635. {
  636. digestmap_set(m, rs->descriptor_digest, rs);
  637. });
  638. }
  639. return digestmap_get(consensus->desc_digest_map, digest);
  640. }
  641. /** Return the consensus view of the status of the router whose current
  642. * <i>descriptor</i> digest in <b>consensus</b> is <b>digest</b>, or NULL if
  643. * no such router is known. */
  644. const routerstatus_t *
  645. router_get_consensus_status_by_descriptor_digest(networkstatus_t *consensus,
  646. const char *digest)
  647. {
  648. return router_get_mutable_consensus_status_by_descriptor_digest(
  649. consensus, digest);
  650. }
  651. /** Return a smartlist of all router descriptor digests in a consensus */
  652. static smartlist_t *
  653. router_get_descriptor_digests_in_consensus(networkstatus_t *consensus)
  654. {
  655. smartlist_t *result = smartlist_new();
  656. digestmap_iter_t *i;
  657. const char *digest;
  658. void *rs;
  659. char *digest_tmp;
  660. for (i = digestmap_iter_init(consensus->desc_digest_map);
  661. !(digestmap_iter_done(i));
  662. i = digestmap_iter_next(consensus->desc_digest_map, i)) {
  663. digestmap_iter_get(i, &digest, &rs);
  664. digest_tmp = tor_malloc(DIGEST_LEN);
  665. memcpy(digest_tmp, digest, DIGEST_LEN);
  666. smartlist_add(result, digest_tmp);
  667. }
  668. return result;
  669. }
  670. /** Return a smartlist of all router descriptor digests in the current
  671. * consensus */
  672. MOCK_IMPL(smartlist_t *,
  673. router_get_descriptor_digests,(void))
  674. {
  675. smartlist_t *result = NULL;
  676. if (current_ns_consensus) {
  677. result =
  678. router_get_descriptor_digests_in_consensus(current_ns_consensus);
  679. }
  680. return result;
  681. }
  682. /** Given the digest of a router descriptor, return its current download
  683. * status, or NULL if the digest is unrecognized. */
  684. MOCK_IMPL(download_status_t *,
  685. router_get_dl_status_by_descriptor_digest,(const char *d))
  686. {
  687. routerstatus_t *rs;
  688. if (!current_ns_consensus)
  689. return NULL;
  690. if ((rs = router_get_mutable_consensus_status_by_descriptor_digest(
  691. current_ns_consensus, d)))
  692. return &rs->dl_status;
  693. return NULL;
  694. }
  695. /** As router_get_consensus_status_by_id, but do not return a const pointer */
  696. routerstatus_t *
  697. router_get_mutable_consensus_status_by_id(const char *digest)
  698. {
  699. const networkstatus_t *ns = networkstatus_get_latest_consensus();
  700. if (!ns)
  701. return NULL;
  702. smartlist_t *rslist = ns->routerstatus_list;
  703. return smartlist_bsearch(rslist, digest,
  704. compare_digest_to_routerstatus_entry);
  705. }
  706. /** Return the consensus view of the status of the router whose identity
  707. * digest is <b>digest</b>, or NULL if we don't know about any such router. */
  708. const routerstatus_t *
  709. router_get_consensus_status_by_id(const char *digest)
  710. {
  711. return router_get_mutable_consensus_status_by_id(digest);
  712. }
  713. /** How frequently do directory authorities re-download fresh networkstatus
  714. * documents? */
  715. #define AUTHORITY_NS_CACHE_INTERVAL (10*60)
  716. /** How frequently do non-authority directory caches re-download fresh
  717. * networkstatus documents? */
  718. #define NONAUTHORITY_NS_CACHE_INTERVAL (60*60)
  719. /** Return true iff, given the options listed in <b>options</b>, <b>flavor</b>
  720. * is the flavor of a consensus networkstatus that we would like to fetch.
  721. *
  722. * For certificate fetches, use we_want_to_fetch_unknown_auth_certs, and
  723. * for serving fetched documents, use directory_caches_dir_info. */
  724. int
  725. we_want_to_fetch_flavor(const or_options_t *options, int flavor)
  726. {
  727. if (flavor < 0 || flavor > N_CONSENSUS_FLAVORS) {
  728. /* This flavor is crazy; we don't want it */
  729. /*XXXX handle unrecognized flavors later */
  730. return 0;
  731. }
  732. if (authdir_mode_v3(options) || directory_caches_dir_info(options)) {
  733. /* We want to serve all flavors to others, regardless if we would use
  734. * it ourselves. */
  735. return 1;
  736. }
  737. if (options->FetchUselessDescriptors) {
  738. /* In order to get all descriptors, we need to fetch all consensuses. */
  739. return 1;
  740. }
  741. /* Otherwise, we want the flavor only if we want to use it to build
  742. * circuits. */
  743. return flavor == usable_consensus_flavor();
  744. }
  745. /** Return true iff, given the options listed in <b>options</b>, we would like
  746. * to fetch and store unknown authority certificates.
  747. *
  748. * For consensus and descriptor fetches, use we_want_to_fetch_flavor, and
  749. * for serving fetched certificates, use directory_caches_unknown_auth_certs.
  750. */
  751. int
  752. we_want_to_fetch_unknown_auth_certs(const or_options_t *options)
  753. {
  754. if (authdir_mode_v3(options) ||
  755. directory_caches_unknown_auth_certs((options))) {
  756. /* We want to serve all certs to others, regardless if we would use
  757. * them ourselves. */
  758. return 1;
  759. }
  760. if (options->FetchUselessDescriptors) {
  761. /* Unknown certificates are definitely useless. */
  762. return 1;
  763. }
  764. /* Otherwise, don't fetch unknown certificates. */
  765. return 0;
  766. }
  767. /** How long will we hang onto a possibly live consensus for which we're
  768. * fetching certs before we check whether there is a better one? */
  769. #define DELAY_WHILE_FETCHING_CERTS (20*60)
  770. /** What is the minimum time we need to have waited fetching certs, before we
  771. * increment the consensus download schedule on failure? */
  772. #define MIN_DELAY_FOR_FETCH_CERT_STATUS_FAILURE (1*60)
  773. /* Check if a downloaded consensus flavor should still wait for certificates
  774. * to download now. If we decide not to wait, check if enough time has passed
  775. * to consider the certificate download failure a separate failure. If so,
  776. * fail dls.
  777. * If waiting for certificates to download, return 1. If not, return 0. */
  778. static int
  779. check_consensus_waiting_for_certs(int flavor, time_t now,
  780. download_status_t *dls)
  781. {
  782. consensus_waiting_for_certs_t *waiting;
  783. /* We should always have a known flavor, because we_want_to_fetch_flavor()
  784. * filters out unknown flavors. */
  785. tor_assert(flavor >= 0 && flavor < N_CONSENSUS_FLAVORS);
  786. waiting = &consensus_waiting_for_certs[flavor];
  787. if (waiting->consensus) {
  788. /* XXXX make sure this doesn't delay sane downloads. */
  789. if (waiting->set_at + DELAY_WHILE_FETCHING_CERTS > now &&
  790. waiting->consensus->valid_until > now) {
  791. return 1;
  792. } else {
  793. if (!waiting->dl_failed) {
  794. if (waiting->set_at + MIN_DELAY_FOR_FETCH_CERT_STATUS_FAILURE > now) {
  795. download_status_failed(dls, 0);
  796. }
  797. waiting->dl_failed=1;
  798. }
  799. }
  800. }
  801. return 0;
  802. }
  803. /** If we want to download a fresh consensus, launch a new download as
  804. * appropriate. */
  805. static void
  806. update_consensus_networkstatus_downloads(time_t now)
  807. {
  808. int i;
  809. const or_options_t *options = get_options();
  810. const int we_are_bootstrapping = networkstatus_consensus_is_bootstrapping(
  811. now);
  812. const int use_multi_conn =
  813. networkstatus_consensus_can_use_multiple_directories(options);
  814. if (should_delay_dir_fetches(options, NULL))
  815. return;
  816. for (i=0; i < N_CONSENSUS_FLAVORS; ++i) {
  817. /* XXXX need some way to download unknown flavors if we are caching. */
  818. const char *resource;
  819. networkstatus_t *c;
  820. int max_in_progress_conns = 1;
  821. if (! we_want_to_fetch_flavor(options, i))
  822. continue;
  823. c = networkstatus_get_latest_consensus_by_flavor(i);
  824. if (! (c && c->valid_after <= now && now <= c->valid_until)) {
  825. /* No live consensus? Get one now!*/
  826. time_to_download_next_consensus[i] = now;
  827. }
  828. if (time_to_download_next_consensus[i] > now)
  829. continue; /* Wait until the current consensus is older. */
  830. resource = networkstatus_get_flavor_name(i);
  831. /* Check if we already have enough connections in progress */
  832. if (we_are_bootstrapping && use_multi_conn) {
  833. max_in_progress_conns =
  834. options->ClientBootstrapConsensusMaxInProgressTries;
  835. }
  836. if (connection_dir_count_by_purpose_and_resource(
  837. DIR_PURPOSE_FETCH_CONSENSUS,
  838. resource)
  839. >= max_in_progress_conns) {
  840. continue;
  841. }
  842. /* Check if we want to launch another download for a usable consensus.
  843. * Only used during bootstrap. */
  844. if (we_are_bootstrapping && use_multi_conn
  845. && i == usable_consensus_flavor()) {
  846. /* Check if we're already downloading a usable consensus */
  847. if (networkstatus_consensus_is_already_downloading(resource))
  848. continue;
  849. /* Make multiple connections for a bootstrap consensus download. */
  850. update_consensus_bootstrap_multiple_downloads(now, options);
  851. } else {
  852. /* Check if we failed downloading a consensus too recently */
  853. int max_dl_tries = options->TestingConsensusMaxDownloadTries;
  854. /* Let's make sure we remembered to update consensus_dl_status */
  855. tor_assert(consensus_dl_status[i].schedule == DL_SCHED_CONSENSUS);
  856. if (!download_status_is_ready(&consensus_dl_status[i],
  857. now,
  858. max_dl_tries)) {
  859. continue;
  860. }
  861. /* Check if we're waiting for certificates to download */
  862. if (check_consensus_waiting_for_certs(i, now, &consensus_dl_status[i]))
  863. continue;
  864. /* Try the requested attempt */
  865. log_info(LD_DIR, "Launching %s standard networkstatus consensus "
  866. "download.", networkstatus_get_flavor_name(i));
  867. directory_get_from_dirserver(DIR_PURPOSE_FETCH_CONSENSUS,
  868. ROUTER_PURPOSE_GENERAL, resource,
  869. PDS_RETRY_IF_NO_SERVERS,
  870. consensus_dl_status[i].want_authority);
  871. }
  872. }
  873. }
  874. /** When we're bootstrapping, launch one or more consensus download
  875. * connections, if schedule indicates connection(s) should be made after now.
  876. * If is_authority, connect to an authority, otherwise, use a fallback
  877. * directory mirror.
  878. */
  879. static void
  880. update_consensus_bootstrap_attempt_downloads(
  881. time_t now,
  882. const or_options_t *options,
  883. download_status_t *dls,
  884. download_want_authority_t want_authority)
  885. {
  886. int use_fallbacks = networkstatus_consensus_can_use_extra_fallbacks(options);
  887. int max_dl_tries = options->ClientBootstrapConsensusMaxDownloadTries;
  888. if (!use_fallbacks) {
  889. max_dl_tries =
  890. options->ClientBootstrapConsensusAuthorityOnlyMaxDownloadTries;
  891. }
  892. const char *resource = networkstatus_get_flavor_name(
  893. usable_consensus_flavor());
  894. /* Let's make sure we remembered to update schedule */
  895. tor_assert(dls->schedule == DL_SCHED_CONSENSUS);
  896. /* Allow for multiple connections in the same second, if the schedule value
  897. * is 0. */
  898. while (download_status_is_ready(dls, now, max_dl_tries)) {
  899. log_info(LD_DIR, "Launching %s bootstrap %s networkstatus consensus "
  900. "download.", resource, (want_authority == DL_WANT_AUTHORITY
  901. ? "authority"
  902. : "mirror"));
  903. directory_get_from_dirserver(DIR_PURPOSE_FETCH_CONSENSUS,
  904. ROUTER_PURPOSE_GENERAL, resource,
  905. PDS_RETRY_IF_NO_SERVERS, want_authority);
  906. /* schedule the next attempt */
  907. download_status_increment_attempt(dls, resource, now);
  908. }
  909. }
  910. /** If we're bootstrapping, check the connection schedules and see if we want
  911. * to make additional, potentially concurrent, consensus download
  912. * connections.
  913. * Only call when bootstrapping, and when we want to make additional
  914. * connections. Only nodes that satisfy
  915. * networkstatus_consensus_can_use_multiple_directories make additional
  916. * connections.
  917. */
  918. static void
  919. update_consensus_bootstrap_multiple_downloads(time_t now,
  920. const or_options_t *options)
  921. {
  922. const int usable_flavor = usable_consensus_flavor();
  923. /* make sure we can use multiple connections */
  924. if (!networkstatus_consensus_can_use_multiple_directories(options)) {
  925. return;
  926. }
  927. /* Launch concurrent consensus download attempt(s) based on the mirror and
  928. * authority schedules. Try the mirror first - this makes it slightly more
  929. * likely that we'll connect to the fallback first, and then end the
  930. * authority connection attempt. */
  931. /* If a consensus download fails because it's waiting for certificates,
  932. * we'll fail both the authority and fallback schedules. This is better than
  933. * failing only one of the schedules, and having the other continue
  934. * unchecked.
  935. */
  936. /* If we don't have or can't use extra fallbacks, don't try them. */
  937. if (networkstatus_consensus_can_use_extra_fallbacks(options)) {
  938. download_status_t *dls_f =
  939. &consensus_bootstrap_dl_status[CONSENSUS_BOOTSTRAP_SOURCE_ANY_DIRSERVER];
  940. if (!check_consensus_waiting_for_certs(usable_flavor, now, dls_f)) {
  941. /* During bootstrap, DL_WANT_ANY_DIRSERVER means "use fallbacks". */
  942. update_consensus_bootstrap_attempt_downloads(now, options, dls_f,
  943. DL_WANT_ANY_DIRSERVER);
  944. }
  945. }
  946. /* Now try an authority. */
  947. download_status_t *dls_a =
  948. &consensus_bootstrap_dl_status[CONSENSUS_BOOTSTRAP_SOURCE_AUTHORITY];
  949. if (!check_consensus_waiting_for_certs(usable_flavor, now, dls_a)) {
  950. update_consensus_bootstrap_attempt_downloads(now, options, dls_a,
  951. DL_WANT_AUTHORITY);
  952. }
  953. }
  954. /** Called when an attempt to download a consensus fails: note that the
  955. * failure occurred, and possibly retry. */
  956. void
  957. networkstatus_consensus_download_failed(int status_code, const char *flavname)
  958. {
  959. int flav = networkstatus_parse_flavor_name(flavname);
  960. if (flav >= 0) {
  961. tor_assert(flav < N_CONSENSUS_FLAVORS);
  962. /* XXXX handle unrecognized flavors */
  963. download_status_failed(&consensus_dl_status[flav], status_code);
  964. /* Retry immediately, if appropriate. */
  965. update_consensus_networkstatus_downloads(time(NULL));
  966. }
  967. }
  968. /** How long do we (as a cache) wait after a consensus becomes non-fresh
  969. * before trying to fetch another? */
  970. #define CONSENSUS_MIN_SECONDS_BEFORE_CACHING 120
  971. /** Update the time at which we'll consider replacing the current
  972. * consensus of flavor <b>flav</b> */
  973. static void
  974. update_consensus_networkstatus_fetch_time_impl(time_t now, int flav)
  975. {
  976. const or_options_t *options = get_options();
  977. networkstatus_t *c = networkstatus_get_latest_consensus_by_flavor(flav);
  978. const char *flavor = networkstatus_get_flavor_name(flav);
  979. if (! we_want_to_fetch_flavor(get_options(), flav))
  980. return;
  981. if (c && c->valid_after <= now && now <= c->valid_until) {
  982. long dl_interval;
  983. long interval = c->fresh_until - c->valid_after;
  984. long min_sec_before_caching = CONSENSUS_MIN_SECONDS_BEFORE_CACHING;
  985. time_t start;
  986. if (min_sec_before_caching > interval/16) {
  987. /* Usually we allow 2-minutes slop factor in case clocks get
  988. desynchronized a little. If we're on a private network with
  989. a crazy-fast voting interval, though, 2 minutes may be too
  990. much. */
  991. min_sec_before_caching = interval/16;
  992. /* make sure we always delay by at least a second before caching */
  993. if (min_sec_before_caching == 0) {
  994. min_sec_before_caching = 1;
  995. }
  996. }
  997. if (directory_fetches_dir_info_early(options)) {
  998. /* We want to cache the next one at some point after this one
  999. * is no longer fresh... */
  1000. start = (time_t)(c->fresh_until + min_sec_before_caching);
  1001. /* Some clients may need the consensus sooner than others. */
  1002. if (options->FetchDirInfoExtraEarly || authdir_mode_v3(options)) {
  1003. dl_interval = 60;
  1004. if (min_sec_before_caching + dl_interval > interval)
  1005. dl_interval = interval/2;
  1006. } else {
  1007. /* But only in the first half-interval after that. */
  1008. dl_interval = interval/2;
  1009. }
  1010. } else {
  1011. /* We're an ordinary client, a bridge, or a hidden service.
  1012. * Give all the caches enough time to download the consensus. */
  1013. start = (time_t)(c->fresh_until + (interval*3)/4);
  1014. /* But download the next one well before this one is expired. */
  1015. dl_interval = ((c->valid_until - start) * 7 )/ 8;
  1016. /* If we're a bridge user, make use of the numbers we just computed
  1017. * to choose the rest of the interval *after* them. */
  1018. if (directory_fetches_dir_info_later(options)) {
  1019. /* Give all the *clients* enough time to download the consensus. */
  1020. start = (time_t)(start + dl_interval + min_sec_before_caching);
  1021. /* But try to get it before ours actually expires. */
  1022. dl_interval = (c->valid_until - start) - min_sec_before_caching;
  1023. }
  1024. }
  1025. /* catch low dl_interval in crazy-fast networks */
  1026. if (dl_interval < 1)
  1027. dl_interval = 1;
  1028. /* catch late start in crazy-fast networks */
  1029. if (start+dl_interval >= c->valid_until)
  1030. start = c->valid_until - dl_interval - 1;
  1031. log_debug(LD_DIR,
  1032. "fresh_until: %ld start: %ld "
  1033. "dl_interval: %ld valid_until: %ld ",
  1034. (long)c->fresh_until, (long)start, dl_interval,
  1035. (long)c->valid_until);
  1036. /* We must not try to replace c while it's still fresh: */
  1037. tor_assert(c->fresh_until < start);
  1038. /* We must download the next one before c is invalid: */
  1039. tor_assert(start+dl_interval < c->valid_until);
  1040. time_to_download_next_consensus[flav] =
  1041. start + crypto_rand_int((int)dl_interval);
  1042. {
  1043. char tbuf1[ISO_TIME_LEN+1];
  1044. char tbuf2[ISO_TIME_LEN+1];
  1045. char tbuf3[ISO_TIME_LEN+1];
  1046. format_local_iso_time(tbuf1, c->fresh_until);
  1047. format_local_iso_time(tbuf2, c->valid_until);
  1048. format_local_iso_time(tbuf3, time_to_download_next_consensus[flav]);
  1049. log_info(LD_DIR, "Live %s consensus %s the most recent until %s and "
  1050. "will expire at %s; fetching the next one at %s.",
  1051. flavor, (c->fresh_until > now) ? "will be" : "was",
  1052. tbuf1, tbuf2, tbuf3);
  1053. }
  1054. } else {
  1055. time_to_download_next_consensus[flav] = now;
  1056. log_info(LD_DIR, "No live %s consensus; we should fetch one immediately.",
  1057. flavor);
  1058. }
  1059. }
  1060. /** Update the time at which we'll consider replacing the current
  1061. * consensus of flavor 'flavor' */
  1062. void
  1063. update_consensus_networkstatus_fetch_time(time_t now)
  1064. {
  1065. int i;
  1066. for (i = 0; i < N_CONSENSUS_FLAVORS; ++i) {
  1067. if (we_want_to_fetch_flavor(get_options(), i))
  1068. update_consensus_networkstatus_fetch_time_impl(now, i);
  1069. }
  1070. }
  1071. /** Return 1 if there's a reason we shouldn't try any directory
  1072. * fetches yet (e.g. we demand bridges and none are yet known).
  1073. * Else return 0.
  1074. * If we return 1 and <b>msg_out</b> is provided, set <b>msg_out</b>
  1075. * to an explanation of why directory fetches are delayed. (If we
  1076. * return 0, we set msg_out to NULL.)
  1077. */
  1078. int
  1079. should_delay_dir_fetches(const or_options_t *options, const char **msg_out)
  1080. {
  1081. if (msg_out) {
  1082. *msg_out = NULL;
  1083. }
  1084. if (options->DisableNetwork) {
  1085. if (msg_out) {
  1086. *msg_out = "DisableNetwork is set.";
  1087. }
  1088. log_info(LD_DIR, "Delaying dir fetches (DisableNetwork is set)");
  1089. return 1;
  1090. }
  1091. if (we_are_hibernating()) {
  1092. if (msg_out) {
  1093. *msg_out = "We are hibernating or shutting down.";
  1094. }
  1095. log_info(LD_DIR, "Delaying dir fetches (Hibernating or shutting down)");
  1096. return 1;
  1097. }
  1098. if (options->UseBridges) {
  1099. if (!any_bridge_descriptors_known()) {
  1100. if (msg_out) {
  1101. *msg_out = "No running bridges";
  1102. }
  1103. log_info(LD_DIR, "Delaying dir fetches (no running bridges known)");
  1104. return 1;
  1105. }
  1106. if (pt_proxies_configuration_pending()) {
  1107. if (msg_out) {
  1108. *msg_out = "Pluggable transport proxies still configuring";
  1109. }
  1110. log_info(LD_DIR, "Delaying dir fetches (pt proxies still configuring)");
  1111. return 1;
  1112. }
  1113. }
  1114. return 0;
  1115. }
  1116. /** Launch requests for networkstatus documents and authority certificates as
  1117. * appropriate. */
  1118. void
  1119. update_networkstatus_downloads(time_t now)
  1120. {
  1121. const or_options_t *options = get_options();
  1122. if (should_delay_dir_fetches(options, NULL))
  1123. return;
  1124. update_consensus_networkstatus_downloads(now);
  1125. update_certificate_downloads(now);
  1126. }
  1127. /** Launch requests as appropriate for missing directory authority
  1128. * certificates. */
  1129. void
  1130. update_certificate_downloads(time_t now)
  1131. {
  1132. int i;
  1133. for (i = 0; i < N_CONSENSUS_FLAVORS; ++i) {
  1134. if (consensus_waiting_for_certs[i].consensus)
  1135. authority_certs_fetch_missing(consensus_waiting_for_certs[i].consensus,
  1136. now, NULL);
  1137. }
  1138. if (current_ns_consensus)
  1139. authority_certs_fetch_missing(current_ns_consensus, now, NULL);
  1140. if (current_md_consensus)
  1141. authority_certs_fetch_missing(current_md_consensus, now, NULL);
  1142. }
  1143. /** Return 1 if we have a consensus but we don't have enough certificates
  1144. * to start using it yet. */
  1145. int
  1146. consensus_is_waiting_for_certs(void)
  1147. {
  1148. return consensus_waiting_for_certs[usable_consensus_flavor()].consensus
  1149. ? 1 : 0;
  1150. }
  1151. /** Look up the currently active (depending on bootstrap status) download
  1152. * status for this consensus flavor and return a pointer to it.
  1153. */
  1154. MOCK_IMPL(download_status_t *,
  1155. networkstatus_get_dl_status_by_flavor,(consensus_flavor_t flavor))
  1156. {
  1157. download_status_t *dl = NULL;
  1158. const int we_are_bootstrapping =
  1159. networkstatus_consensus_is_bootstrapping(time(NULL));
  1160. if ((int)flavor <= N_CONSENSUS_FLAVORS) {
  1161. dl = &((we_are_bootstrapping ?
  1162. consensus_bootstrap_dl_status : consensus_dl_status)[flavor]);
  1163. }
  1164. return dl;
  1165. }
  1166. /** Look up the bootstrap download status for this consensus flavor
  1167. * and return a pointer to it. */
  1168. MOCK_IMPL(download_status_t *,
  1169. networkstatus_get_dl_status_by_flavor_bootstrap,(consensus_flavor_t flavor))
  1170. {
  1171. download_status_t *dl = NULL;
  1172. if ((int)flavor <= N_CONSENSUS_FLAVORS) {
  1173. dl = &(consensus_bootstrap_dl_status[flavor]);
  1174. }
  1175. return dl;
  1176. }
  1177. /** Look up the running (non-bootstrap) download status for this consensus
  1178. * flavor and return a pointer to it. */
  1179. MOCK_IMPL(download_status_t *,
  1180. networkstatus_get_dl_status_by_flavor_running,(consensus_flavor_t flavor))
  1181. {
  1182. download_status_t *dl = NULL;
  1183. if ((int)flavor <= N_CONSENSUS_FLAVORS) {
  1184. dl = &(consensus_dl_status[flavor]);
  1185. }
  1186. return dl;
  1187. }
  1188. /** Return the most recent consensus that we have downloaded, or NULL if we
  1189. * don't have one. */
  1190. MOCK_IMPL(networkstatus_t *,
  1191. networkstatus_get_latest_consensus,(void))
  1192. {
  1193. if (we_use_microdescriptors_for_circuits(get_options()))
  1194. return current_md_consensus;
  1195. else
  1196. return current_ns_consensus;
  1197. }
  1198. /** Return the latest consensus we have whose flavor matches <b>f</b>, or NULL
  1199. * if we don't have one. */
  1200. MOCK_IMPL(networkstatus_t *,
  1201. networkstatus_get_latest_consensus_by_flavor,(consensus_flavor_t f))
  1202. {
  1203. if (f == FLAV_NS)
  1204. return current_ns_consensus;
  1205. else if (f == FLAV_MICRODESC)
  1206. return current_md_consensus;
  1207. else {
  1208. tor_assert(0);
  1209. return NULL;
  1210. }
  1211. }
  1212. /** Return the most recent consensus that we have downloaded, or NULL if it is
  1213. * no longer live. */
  1214. MOCK_IMPL(networkstatus_t *,
  1215. networkstatus_get_live_consensus,(time_t now))
  1216. {
  1217. networkstatus_t *ns = networkstatus_get_latest_consensus();
  1218. if (ns && networkstatus_is_live(ns, now))
  1219. return ns;
  1220. else
  1221. return NULL;
  1222. }
  1223. /** Given a consensus in <b>ns</b>, return true iff currently live and
  1224. * unexpired. */
  1225. int
  1226. networkstatus_is_live(const networkstatus_t *ns, time_t now)
  1227. {
  1228. return (ns->valid_after <= now && now <= ns->valid_until);
  1229. }
  1230. /** Determine if <b>consensus</b> is valid or expired recently enough that
  1231. * we can still use it.
  1232. *
  1233. * Return 1 if the consensus is reasonably live, or 0 if it is too old.
  1234. */
  1235. int
  1236. networkstatus_consensus_reasonably_live(const networkstatus_t *consensus,
  1237. time_t now)
  1238. {
  1239. if (BUG(!consensus))
  1240. return 0;
  1241. return networkstatus_valid_until_is_reasonably_live(consensus->valid_until,
  1242. now);
  1243. }
  1244. /** As networkstatus_consensus_reasonably_live, but takes a valid_until
  1245. * time rather than an entire consensus. */
  1246. int
  1247. networkstatus_valid_until_is_reasonably_live(time_t valid_until,
  1248. time_t now)
  1249. {
  1250. #define REASONABLY_LIVE_TIME (24*60*60)
  1251. return (now <= valid_until + REASONABLY_LIVE_TIME);
  1252. }
  1253. /* XXXX remove this in favor of get_live_consensus. But actually,
  1254. * leave something like it for bridge users, who need to not totally
  1255. * lose if they spend a while fetching a new consensus. */
  1256. /** As networkstatus_get_live_consensus(), but is way more tolerant of expired
  1257. * consensuses. */
  1258. networkstatus_t *
  1259. networkstatus_get_reasonably_live_consensus(time_t now, int flavor)
  1260. {
  1261. networkstatus_t *consensus =
  1262. networkstatus_get_latest_consensus_by_flavor(flavor);
  1263. if (consensus &&
  1264. consensus->valid_after <= now &&
  1265. networkstatus_consensus_reasonably_live(consensus, now))
  1266. return consensus;
  1267. else
  1268. return NULL;
  1269. }
  1270. /** Check if we need to download a consensus during tor's bootstrap phase.
  1271. * If we have no consensus, or our consensus is unusably old, return 1.
  1272. * As soon as we have received a consensus, return 0, even if we don't have
  1273. * enough certificates to validate it.
  1274. * If a fallback directory gives us a consensus we can never get certs for,
  1275. * check_consensus_waiting_for_certs() will wait 20 minutes before failing
  1276. * the cert downloads. After that, a new consensus will be fetched from a
  1277. * randomly chosen fallback. */
  1278. MOCK_IMPL(int,
  1279. networkstatus_consensus_is_bootstrapping,(time_t now))
  1280. {
  1281. /* If we have a validated, reasonably live consensus, we're not
  1282. * bootstrapping a consensus at all. */
  1283. if (networkstatus_get_reasonably_live_consensus(
  1284. now,
  1285. usable_consensus_flavor())) {
  1286. return 0;
  1287. }
  1288. /* If we have a consensus, but we're waiting for certificates,
  1289. * we're not waiting for a consensus download while bootstrapping. */
  1290. if (consensus_is_waiting_for_certs()) {
  1291. return 0;
  1292. }
  1293. /* If we have no consensus, or our consensus is very old, we are
  1294. * bootstrapping, and we need to download a consensus. */
  1295. return 1;
  1296. }
  1297. /** Check if we can use multiple directories for a consensus download.
  1298. * Only clients (including bridge relays, which act like clients) benefit
  1299. * from multiple simultaneous consensus downloads. */
  1300. int
  1301. networkstatus_consensus_can_use_multiple_directories(
  1302. const or_options_t *options)
  1303. {
  1304. /* If we are a client, bridge, bridge client, or hidden service */
  1305. return !public_server_mode(options);
  1306. }
  1307. /** Check if we can use fallback directory mirrors for a consensus download.
  1308. * If we have fallbacks and don't want to fetch from the authorities,
  1309. * we can use them. */
  1310. MOCK_IMPL(int,
  1311. networkstatus_consensus_can_use_extra_fallbacks,(const or_options_t *options))
  1312. {
  1313. /* The list length comparisons are a quick way to check if we have any
  1314. * non-authority fallback directories. If we ever have any authorities that
  1315. * aren't fallback directories, we will need to change this code. */
  1316. tor_assert(smartlist_len(router_get_fallback_dir_servers())
  1317. >= smartlist_len(router_get_trusted_dir_servers()));
  1318. /* If we don't fetch from the authorities, and we have additional mirrors,
  1319. * we can use them. */
  1320. return (!directory_fetches_from_authorities(options)
  1321. && (smartlist_len(router_get_fallback_dir_servers())
  1322. > smartlist_len(router_get_trusted_dir_servers())));
  1323. }
  1324. /* Is there a consensus fetch for flavor <b>resource</b> that's far
  1325. * enough along to be attached to a circuit? */
  1326. int
  1327. networkstatus_consensus_is_already_downloading(const char *resource)
  1328. {
  1329. int answer = 0;
  1330. /* First, get a list of all the dir conns that are fetching a consensus,
  1331. * fetching *this* consensus, and are in state "reading" (meaning they
  1332. * have already flushed their request onto the socks connection). */
  1333. smartlist_t *fetching_conns =
  1334. connection_dir_list_by_purpose_resource_and_state(
  1335. DIR_PURPOSE_FETCH_CONSENSUS, resource, DIR_CONN_STATE_CLIENT_READING);
  1336. /* Then, walk through each conn, to see if its linked socks connection
  1337. * is in an attached state. We have to check this separately, since with
  1338. * the optimistic data feature, fetches can send their request to the
  1339. * socks connection and go into state 'reading', even before they're
  1340. * attached to any circuit. */
  1341. SMARTLIST_FOREACH_BEGIN(fetching_conns, dir_connection_t *, dirconn) {
  1342. /* Do any of these other dir conns have a linked socks conn that is
  1343. * attached to a circuit already? */
  1344. connection_t *base = TO_CONN(dirconn);
  1345. if (base->linked_conn &&
  1346. base->linked_conn->type == CONN_TYPE_AP &&
  1347. !AP_CONN_STATE_IS_UNATTACHED(base->linked_conn->state)) {
  1348. answer = 1;
  1349. break; /* stop looping, because we know the answer will be yes */
  1350. }
  1351. } SMARTLIST_FOREACH_END(dirconn);
  1352. smartlist_free(fetching_conns);
  1353. return answer;
  1354. }
  1355. /** Given two router status entries for the same router identity, return 1 if
  1356. * if the contents have changed between them. Otherwise, return 0. */
  1357. static int
  1358. routerstatus_has_changed(const routerstatus_t *a, const routerstatus_t *b)
  1359. {
  1360. tor_assert(tor_memeq(a->identity_digest, b->identity_digest, DIGEST_LEN));
  1361. return strcmp(a->nickname, b->nickname) ||
  1362. fast_memneq(a->descriptor_digest, b->descriptor_digest, DIGEST_LEN) ||
  1363. a->addr != b->addr ||
  1364. a->or_port != b->or_port ||
  1365. a->dir_port != b->dir_port ||
  1366. a->is_authority != b->is_authority ||
  1367. a->is_exit != b->is_exit ||
  1368. a->is_stable != b->is_stable ||
  1369. a->is_fast != b->is_fast ||
  1370. a->is_flagged_running != b->is_flagged_running ||
  1371. a->is_named != b->is_named ||
  1372. a->is_unnamed != b->is_unnamed ||
  1373. a->is_valid != b->is_valid ||
  1374. a->is_possible_guard != b->is_possible_guard ||
  1375. a->is_bad_exit != b->is_bad_exit ||
  1376. a->is_hs_dir != b->is_hs_dir;
  1377. // XXXX this function needs a huge refactoring; it has gotten out
  1378. // XXXX of sync with routerstatus_t, and it will do so again.
  1379. }
  1380. /** Notify controllers of any router status entries that changed between
  1381. * <b>old_c</b> and <b>new_c</b>. */
  1382. static void
  1383. notify_control_networkstatus_changed(const networkstatus_t *old_c,
  1384. const networkstatus_t *new_c)
  1385. {
  1386. smartlist_t *changed;
  1387. if (old_c == new_c)
  1388. return;
  1389. /* tell the controller exactly which relays are still listed, as well
  1390. * as what they're listed as */
  1391. control_event_newconsensus(new_c);
  1392. if (!control_event_is_interesting(EVENT_NS))
  1393. return;
  1394. if (!old_c) {
  1395. control_event_networkstatus_changed(new_c->routerstatus_list);
  1396. return;
  1397. }
  1398. changed = smartlist_new();
  1399. SMARTLIST_FOREACH_JOIN(
  1400. old_c->routerstatus_list, const routerstatus_t *, rs_old,
  1401. new_c->routerstatus_list, const routerstatus_t *, rs_new,
  1402. tor_memcmp(rs_old->identity_digest,
  1403. rs_new->identity_digest, DIGEST_LEN),
  1404. smartlist_add(changed, (void*) rs_new)) {
  1405. if (routerstatus_has_changed(rs_old, rs_new))
  1406. smartlist_add(changed, (void*)rs_new);
  1407. } SMARTLIST_FOREACH_JOIN_END(rs_old, rs_new);
  1408. control_event_networkstatus_changed(changed);
  1409. smartlist_free(changed);
  1410. }
  1411. /* Called when the consensus has changed from old_c to new_c. */
  1412. static void
  1413. notify_networkstatus_changed(const networkstatus_t *old_c,
  1414. const networkstatus_t *new_c)
  1415. {
  1416. notify_control_networkstatus_changed(old_c, new_c);
  1417. scheduler_notify_networkstatus_changed(old_c, new_c);
  1418. }
  1419. /** Copy all the ancillary information (like router download status and so on)
  1420. * from <b>old_c</b> to <b>new_c</b>. */
  1421. static void
  1422. networkstatus_copy_old_consensus_info(networkstatus_t *new_c,
  1423. const networkstatus_t *old_c)
  1424. {
  1425. if (old_c == new_c)
  1426. return;
  1427. if (!old_c || !smartlist_len(old_c->routerstatus_list))
  1428. return;
  1429. SMARTLIST_FOREACH_JOIN(old_c->routerstatus_list, routerstatus_t *, rs_old,
  1430. new_c->routerstatus_list, routerstatus_t *, rs_new,
  1431. tor_memcmp(rs_old->identity_digest,
  1432. rs_new->identity_digest, DIGEST_LEN),
  1433. STMT_NIL) {
  1434. /* Okay, so we're looking at the same identity. */
  1435. rs_new->last_dir_503_at = rs_old->last_dir_503_at;
  1436. if (tor_memeq(rs_old->descriptor_digest, rs_new->descriptor_digest,
  1437. DIGEST256_LEN)) {
  1438. /* And the same descriptor too! */
  1439. memcpy(&rs_new->dl_status, &rs_old->dl_status,sizeof(download_status_t));
  1440. }
  1441. } SMARTLIST_FOREACH_JOIN_END(rs_old, rs_new);
  1442. }
  1443. #ifdef TOR_UNIT_TESTS
  1444. /**Accept a <b>flavor</b> consensus <b>c</b> without any additional
  1445. * validation. This is exclusively for unit tests.
  1446. * We copy any ancillary information from a pre-existing consensus
  1447. * and then free the current one and replace it with the newly
  1448. * provided instance. Returns -1 on unrecognized flavor, 0 otherwise.
  1449. */
  1450. int
  1451. networkstatus_set_current_consensus_from_ns(networkstatus_t *c,
  1452. const char *flavor)
  1453. {
  1454. int flav = networkstatus_parse_flavor_name(flavor);
  1455. switch (flav) {
  1456. case FLAV_NS:
  1457. if (current_ns_consensus) {
  1458. networkstatus_copy_old_consensus_info(c, current_ns_consensus);
  1459. networkstatus_vote_free(current_ns_consensus);
  1460. }
  1461. current_ns_consensus = c;
  1462. break;
  1463. case FLAV_MICRODESC:
  1464. if (current_md_consensus) {
  1465. networkstatus_copy_old_consensus_info(c, current_md_consensus);
  1466. networkstatus_vote_free(current_md_consensus);
  1467. }
  1468. current_md_consensus = c;
  1469. break;
  1470. }
  1471. return current_md_consensus ? 0 : -1;
  1472. }
  1473. #endif /* defined(TOR_UNIT_TESTS) */
  1474. /**
  1475. * Return true if any option is set in <b>options</b> to make us behave
  1476. * as a client.
  1477. *
  1478. * XXXX If we need this elsewhere at any point, we should make it nonstatic
  1479. * XXXX and move it into another file.
  1480. */
  1481. static int
  1482. any_client_port_set(const or_options_t *options)
  1483. {
  1484. return (options->SocksPort_set ||
  1485. options->TransPort_set ||
  1486. options->NATDPort_set ||
  1487. options->ControlPort_set ||
  1488. options->DNSPort_set ||
  1489. options->HTTPTunnelPort_set);
  1490. }
  1491. /**
  1492. * Helper for handle_missing_protocol_warning: handles either the
  1493. * client case (if <b>is_client</b> is set) or the server case otherwise.
  1494. */
  1495. static void
  1496. handle_missing_protocol_warning_impl(const networkstatus_t *c,
  1497. int is_client)
  1498. {
  1499. char *protocol_warning = NULL;
  1500. int should_exit = networkstatus_check_required_protocols(c,
  1501. is_client,
  1502. &protocol_warning);
  1503. if (protocol_warning) {
  1504. tor_log(should_exit ? LOG_ERR : LOG_WARN,
  1505. LD_GENERAL,
  1506. "%s", protocol_warning);
  1507. }
  1508. if (should_exit) {
  1509. tor_assert_nonfatal(protocol_warning);
  1510. }
  1511. tor_free(protocol_warning);
  1512. if (should_exit)
  1513. exit(1); // XXXX bad exit: should return from main.
  1514. }
  1515. /** Called when we have received a networkstatus <b>c</b>. If there are
  1516. * any _required_ protocols we are missing, log an error and exit
  1517. * immediately. If there are any _recommended_ protocols we are missing,
  1518. * warn. */
  1519. static void
  1520. handle_missing_protocol_warning(const networkstatus_t *c,
  1521. const or_options_t *options)
  1522. {
  1523. const int is_server = server_mode(options);
  1524. const int is_client = any_client_port_set(options) || !is_server;
  1525. if (is_server)
  1526. handle_missing_protocol_warning_impl(c, 0);
  1527. if (is_client)
  1528. handle_missing_protocol_warning_impl(c, 1);
  1529. }
  1530. /** Try to replace the current cached v3 networkstatus with the one in
  1531. * <b>consensus</b>. If we don't have enough certificates to validate it,
  1532. * store it in consensus_waiting_for_certs and launch a certificate fetch.
  1533. *
  1534. * If flags & NSSET_FROM_CACHE, this networkstatus has come from the disk
  1535. * cache. If flags & NSSET_WAS_WAITING_FOR_CERTS, this networkstatus was
  1536. * already received, but we were waiting for certificates on it. If flags &
  1537. * NSSET_DONT_DOWNLOAD_CERTS, do not launch certificate downloads as needed.
  1538. * If flags & NSSET_ACCEPT_OBSOLETE, then we should be willing to take this
  1539. * consensus, even if it comes from many days in the past.
  1540. *
  1541. * If source_dir is non-NULL, it's the identity digest for a directory that
  1542. * we've just successfully retrieved a consensus or certificates from, so try
  1543. * it first to fetch any missing certificates.
  1544. *
  1545. * Return 0 on success, <0 on failure. On failure, caller should increment
  1546. * the failure count as appropriate.
  1547. *
  1548. * We return -1 for mild failures that don't need to be reported to the
  1549. * user, and -2 for more serious problems.
  1550. */
  1551. int
  1552. networkstatus_set_current_consensus(const char *consensus,
  1553. const char *flavor,
  1554. unsigned flags,
  1555. const char *source_dir)
  1556. {
  1557. networkstatus_t *c=NULL;
  1558. int r, result = -1;
  1559. time_t now = approx_time();
  1560. const or_options_t *options = get_options();
  1561. char *unverified_fname = NULL, *consensus_fname = NULL;
  1562. int flav = networkstatus_parse_flavor_name(flavor);
  1563. const unsigned from_cache = flags & NSSET_FROM_CACHE;
  1564. const unsigned was_waiting_for_certs = flags & NSSET_WAS_WAITING_FOR_CERTS;
  1565. const unsigned dl_certs = !(flags & NSSET_DONT_DOWNLOAD_CERTS);
  1566. const unsigned accept_obsolete = flags & NSSET_ACCEPT_OBSOLETE;
  1567. const unsigned require_flavor = flags & NSSET_REQUIRE_FLAVOR;
  1568. const common_digests_t *current_digests = NULL;
  1569. consensus_waiting_for_certs_t *waiting = NULL;
  1570. time_t current_valid_after = 0;
  1571. int free_consensus = 1; /* Free 'c' at the end of the function */
  1572. int old_ewma_enabled;
  1573. int checked_protocols_already = 0;
  1574. if (flav < 0) {
  1575. /* XXXX we don't handle unrecognized flavors yet. */
  1576. log_warn(LD_BUG, "Unrecognized consensus flavor %s", flavor);
  1577. return -2;
  1578. }
  1579. /* Make sure it's parseable. */
  1580. c = networkstatus_parse_vote_from_string(consensus, NULL, NS_TYPE_CONSENSUS);
  1581. if (!c) {
  1582. log_warn(LD_DIR, "Unable to parse networkstatus consensus");
  1583. result = -2;
  1584. goto done;
  1585. }
  1586. if (from_cache && !was_waiting_for_certs) {
  1587. /* We previously stored this; check _now_ to make sure that version-kills
  1588. * really work. This happens even before we check signatures: we did so
  1589. * before when we stored this to disk. This does mean an attacker who can
  1590. * write to the datadir can make us not start: such an attacker could
  1591. * already harm us by replacing our guards, which would be worse. */
  1592. checked_protocols_already = 1;
  1593. handle_missing_protocol_warning(c, options);
  1594. }
  1595. if ((int)c->flavor != flav) {
  1596. /* This wasn't the flavor we thought we were getting. */
  1597. if (require_flavor) {
  1598. log_warn(LD_DIR, "Got consensus with unexpected flavor %s (wanted %s)",
  1599. networkstatus_get_flavor_name(c->flavor), flavor);
  1600. goto done;
  1601. }
  1602. flav = c->flavor;
  1603. flavor = networkstatus_get_flavor_name(flav);
  1604. }
  1605. if (flav != usable_consensus_flavor() &&
  1606. !we_want_to_fetch_flavor(options, flav)) {
  1607. /* This consensus is totally boring to us: we won't use it, we didn't want
  1608. * it, and we won't serve it. Drop it. */
  1609. goto done;
  1610. }
  1611. if (from_cache && !accept_obsolete &&
  1612. c->valid_until < now-OLD_ROUTER_DESC_MAX_AGE) {
  1613. log_info(LD_DIR, "Loaded an expired consensus. Discarding.");
  1614. goto done;
  1615. }
  1616. if (!strcmp(flavor, "ns")) {
  1617. consensus_fname = get_datadir_fname("cached-consensus");
  1618. unverified_fname = get_datadir_fname("unverified-consensus");
  1619. if (current_ns_consensus) {
  1620. current_digests = &current_ns_consensus->digests;
  1621. current_valid_after = current_ns_consensus->valid_after;
  1622. }
  1623. } else if (!strcmp(flavor, "microdesc")) {
  1624. consensus_fname = get_datadir_fname("cached-microdesc-consensus");
  1625. unverified_fname = get_datadir_fname("unverified-microdesc-consensus");
  1626. if (current_md_consensus) {
  1627. current_digests = &current_md_consensus->digests;
  1628. current_valid_after = current_md_consensus->valid_after;
  1629. }
  1630. } else {
  1631. cached_dir_t *cur;
  1632. char buf[128];
  1633. tor_snprintf(buf, sizeof(buf), "cached-%s-consensus", flavor);
  1634. consensus_fname = get_datadir_fname(buf);
  1635. tor_snprintf(buf, sizeof(buf), "unverified-%s-consensus", flavor);
  1636. unverified_fname = get_datadir_fname(buf);
  1637. cur = dirserv_get_consensus(flavor);
  1638. if (cur) {
  1639. current_digests = &cur->digests;
  1640. current_valid_after = cur->published;
  1641. }
  1642. }
  1643. if (current_digests &&
  1644. tor_memeq(&c->digests, current_digests, sizeof(c->digests))) {
  1645. /* We already have this one. That's a failure. */
  1646. log_info(LD_DIR, "Got a %s consensus we already have", flavor);
  1647. goto done;
  1648. }
  1649. if (current_valid_after && c->valid_after <= current_valid_after) {
  1650. /* We have a newer one. There's no point in accepting this one,
  1651. * even if it's great. */
  1652. log_info(LD_DIR, "Got a %s consensus at least as old as the one we have",
  1653. flavor);
  1654. goto done;
  1655. }
  1656. /* Make sure it's signed enough. */
  1657. if ((r=networkstatus_check_consensus_signature(c, 1))<0) {
  1658. if (r == -1) {
  1659. /* Okay, so it _might_ be signed enough if we get more certificates. */
  1660. if (!was_waiting_for_certs) {
  1661. log_info(LD_DIR,
  1662. "Not enough certificates to check networkstatus consensus");
  1663. }
  1664. if (!current_valid_after ||
  1665. c->valid_after > current_valid_after) {
  1666. waiting = &consensus_waiting_for_certs[flav];
  1667. networkstatus_vote_free(waiting->consensus);
  1668. tor_free(waiting->body);
  1669. waiting->consensus = c;
  1670. free_consensus = 0;
  1671. waiting->body = tor_strdup(consensus);
  1672. waiting->set_at = now;
  1673. waiting->dl_failed = 0;
  1674. if (!from_cache) {
  1675. write_str_to_file(unverified_fname, consensus, 0);
  1676. }
  1677. if (dl_certs)
  1678. authority_certs_fetch_missing(c, now, source_dir);
  1679. /* This case is not a success or a failure until we get the certs
  1680. * or fail to get the certs. */
  1681. result = 0;
  1682. } else {
  1683. /* Even if we had enough signatures, we'd never use this as the
  1684. * latest consensus. */
  1685. if (was_waiting_for_certs && from_cache)
  1686. if (unlink(unverified_fname) != 0) {
  1687. log_warn(LD_FS,
  1688. "Failed to unlink %s: %s",
  1689. unverified_fname, strerror(errno));
  1690. }
  1691. }
  1692. goto done;
  1693. } else {
  1694. /* This can never be signed enough: Kill it. */
  1695. if (!was_waiting_for_certs) {
  1696. log_warn(LD_DIR, "Not enough good signatures on networkstatus "
  1697. "consensus");
  1698. result = -2;
  1699. }
  1700. if (was_waiting_for_certs && (r < -1) && from_cache) {
  1701. if (unlink(unverified_fname) != 0) {
  1702. log_warn(LD_FS,
  1703. "Failed to unlink %s: %s",
  1704. unverified_fname, strerror(errno));
  1705. }
  1706. }
  1707. goto done;
  1708. }
  1709. }
  1710. if (!from_cache && flav == usable_consensus_flavor())
  1711. control_event_client_status(LOG_NOTICE, "CONSENSUS_ARRIVED");
  1712. if (!checked_protocols_already) {
  1713. handle_missing_protocol_warning(c, options);
  1714. }
  1715. /* Are we missing any certificates at all? */
  1716. if (r != 1 && dl_certs)
  1717. authority_certs_fetch_missing(c, now, source_dir);
  1718. const int is_usable_flavor = flav == usable_consensus_flavor();
  1719. if (is_usable_flavor) {
  1720. notify_networkstatus_changed(networkstatus_get_latest_consensus(), c);
  1721. }
  1722. if (flav == FLAV_NS) {
  1723. if (current_ns_consensus) {
  1724. networkstatus_copy_old_consensus_info(c, current_ns_consensus);
  1725. networkstatus_vote_free(current_ns_consensus);
  1726. /* Defensive programming : we should set current_ns_consensus very soon
  1727. * but we're about to call some stuff in the meantime, and leaving this
  1728. * dangling pointer around has proven to be trouble. */
  1729. current_ns_consensus = NULL;
  1730. }
  1731. current_ns_consensus = c;
  1732. free_consensus = 0; /* avoid free */
  1733. } else if (flav == FLAV_MICRODESC) {
  1734. if (current_md_consensus) {
  1735. networkstatus_copy_old_consensus_info(c, current_md_consensus);
  1736. networkstatus_vote_free(current_md_consensus);
  1737. /* more defensive programming */
  1738. current_md_consensus = NULL;
  1739. }
  1740. current_md_consensus = c;
  1741. free_consensus = 0; /* avoid free */
  1742. }
  1743. waiting = &consensus_waiting_for_certs[flav];
  1744. if (waiting->consensus &&
  1745. waiting->consensus->valid_after <= c->valid_after) {
  1746. networkstatus_vote_free(waiting->consensus);
  1747. waiting->consensus = NULL;
  1748. if (consensus != waiting->body)
  1749. tor_free(waiting->body);
  1750. else
  1751. waiting->body = NULL;
  1752. waiting->set_at = 0;
  1753. waiting->dl_failed = 0;
  1754. if (unlink(unverified_fname) != 0) {
  1755. log_warn(LD_FS,
  1756. "Failed to unlink %s: %s",
  1757. unverified_fname, strerror(errno));
  1758. }
  1759. }
  1760. if (is_usable_flavor) {
  1761. /* The "current" consensus has just been set and it is a usable flavor so
  1762. * the first thing we need to do is recalculate the voting schedule static
  1763. * object so we can use the timings in there needed by some subsystems
  1764. * such as hidden service and shared random. */
  1765. dirvote_recalculate_timing(options, now);
  1766. nodelist_set_consensus(c);
  1767. /* XXXXNM Microdescs: needs a non-ns variant. ???? NM*/
  1768. update_consensus_networkstatus_fetch_time(now);
  1769. /* Update ewma and adjust policy if needed; first cache the old value */
  1770. old_ewma_enabled = cell_ewma_enabled();
  1771. /* Change the cell EWMA settings */
  1772. cell_ewma_set_scale_factor(options, c);
  1773. /* If we just enabled ewma, set the cmux policy on all active channels */
  1774. if (cell_ewma_enabled() && !old_ewma_enabled) {
  1775. channel_set_cmux_policy_everywhere(&ewma_policy);
  1776. } else if (!cell_ewma_enabled() && old_ewma_enabled) {
  1777. /* Turn it off everywhere */
  1778. channel_set_cmux_policy_everywhere(NULL);
  1779. }
  1780. /* XXXX this call might be unnecessary here: can changing the
  1781. * current consensus really alter our view of any OR's rate limits? */
  1782. connection_or_update_token_buckets(get_connection_array(), options);
  1783. circuit_build_times_new_consensus_params(
  1784. get_circuit_build_times_mutable(), c);
  1785. channelpadding_new_consensus_params(c);
  1786. }
  1787. /* Reset the failure count only if this consensus is actually valid. */
  1788. if (c->valid_after <= now && now <= c->valid_until) {
  1789. download_status_reset(&consensus_dl_status[flav]);
  1790. } else {
  1791. if (!from_cache)
  1792. download_status_failed(&consensus_dl_status[flav], 0);
  1793. }
  1794. if (we_want_to_fetch_flavor(options, flav)) {
  1795. dirserv_set_cached_consensus_networkstatus(consensus,
  1796. flavor,
  1797. &c->digests,
  1798. c->digest_sha3_as_signed,
  1799. c->valid_after);
  1800. if (dir_server_mode(get_options())) {
  1801. consdiffmgr_add_consensus(consensus, c);
  1802. }
  1803. }
  1804. if (!from_cache) {
  1805. write_str_to_file(consensus_fname, consensus, 0);
  1806. }
  1807. /** If a consensus appears more than this many seconds before its declared
  1808. * valid-after time, declare that our clock is skewed. */
  1809. #define EARLY_CONSENSUS_NOTICE_SKEW 60
  1810. if (now < c->valid_after - EARLY_CONSENSUS_NOTICE_SKEW) {
  1811. char tbuf[ISO_TIME_LEN+1];
  1812. char dbuf[64];
  1813. long delta = now - c->valid_after;
  1814. char *flavormsg = NULL;
  1815. format_iso_time(tbuf, c->valid_after);
  1816. format_time_interval(dbuf, sizeof(dbuf), delta);
  1817. log_warn(LD_GENERAL, "Our clock is %s behind the time published in the "
  1818. "consensus network status document (%s UTC). Tor needs an "
  1819. "accurate clock to work correctly. Please check your time and "
  1820. "date settings!", dbuf, tbuf);
  1821. tor_asprintf(&flavormsg, "%s flavor consensus", flavor);
  1822. clock_skew_warning(NULL, delta, 1, LD_GENERAL, flavormsg, "CONSENSUS");
  1823. tor_free(flavormsg);
  1824. }
  1825. /* We got a new consesus. Reset our md fetch fail cache */
  1826. microdesc_reset_outdated_dirservers_list();
  1827. router_dir_info_changed();
  1828. result = 0;
  1829. done:
  1830. if (free_consensus)
  1831. networkstatus_vote_free(c);
  1832. tor_free(consensus_fname);
  1833. tor_free(unverified_fname);
  1834. return result;
  1835. }
  1836. /** Called when we have gotten more certificates: see whether we can
  1837. * now verify a pending consensus.
  1838. *
  1839. * If source_dir is non-NULL, it's the identity digest for a directory that
  1840. * we've just successfully retrieved certificates from, so try it first to
  1841. * fetch any missing certificates.
  1842. */
  1843. void
  1844. networkstatus_note_certs_arrived(const char *source_dir)
  1845. {
  1846. int i;
  1847. for (i=0; i<N_CONSENSUS_FLAVORS; ++i) {
  1848. consensus_waiting_for_certs_t *waiting = &consensus_waiting_for_certs[i];
  1849. if (!waiting->consensus)
  1850. continue;
  1851. if (networkstatus_check_consensus_signature(waiting->consensus, 0)>=0) {
  1852. char *waiting_body = waiting->body;
  1853. if (!networkstatus_set_current_consensus(
  1854. waiting_body,
  1855. networkstatus_get_flavor_name(i),
  1856. NSSET_WAS_WAITING_FOR_CERTS,
  1857. source_dir)) {
  1858. tor_free(waiting_body);
  1859. }
  1860. }
  1861. }
  1862. }
  1863. /** If the network-status list has changed since the last time we called this
  1864. * function, update the status of every routerinfo from the network-status
  1865. * list. If <b>dir_version</b> is 2, it's a v2 networkstatus that changed.
  1866. * If <b>dir_version</b> is 3, it's a v3 consensus that changed.
  1867. */
  1868. void
  1869. routers_update_all_from_networkstatus(time_t now, int dir_version)
  1870. {
  1871. routerlist_t *rl = router_get_routerlist();
  1872. networkstatus_t *consensus = networkstatus_get_reasonably_live_consensus(now,
  1873. FLAV_NS);
  1874. if (!consensus || dir_version < 3) /* nothing more we should do */
  1875. return;
  1876. /* calls router_dir_info_changed() when it's done -- more routers
  1877. * might be up or down now, which might affect whether there's enough
  1878. * directory info. */
  1879. routers_update_status_from_consensus_networkstatus(rl->routers, 0);
  1880. SMARTLIST_FOREACH(rl->routers, routerinfo_t *, ri,
  1881. ri->cache_info.routerlist_index = ri_sl_idx);
  1882. if (rl->old_routers)
  1883. signed_descs_update_status_from_consensus_networkstatus(rl->old_routers);
  1884. if (!have_warned_about_old_version) {
  1885. int is_server = server_mode(get_options());
  1886. version_status_t status;
  1887. const char *recommended = is_server ?
  1888. consensus->server_versions : consensus->client_versions;
  1889. status = tor_version_is_obsolete(VERSION, recommended);
  1890. if (status == VS_RECOMMENDED) {
  1891. log_info(LD_GENERAL, "The directory authorities say my version is ok.");
  1892. } else if (status == VS_EMPTY) {
  1893. log_info(LD_GENERAL,
  1894. "The directory authorities don't recommend any versions.");
  1895. } else if (status == VS_NEW || status == VS_NEW_IN_SERIES) {
  1896. if (!have_warned_about_new_version) {
  1897. log_notice(LD_GENERAL, "This version of Tor (%s) is newer than any "
  1898. "recommended version%s, according to the directory "
  1899. "authorities. Recommended versions are: %s",
  1900. VERSION,
  1901. status == VS_NEW_IN_SERIES ? " in its series" : "",
  1902. recommended);
  1903. have_warned_about_new_version = 1;
  1904. control_event_general_status(LOG_WARN, "DANGEROUS_VERSION "
  1905. "CURRENT=%s REASON=%s RECOMMENDED=\"%s\"",
  1906. VERSION, "NEW", recommended);
  1907. }
  1908. } else {
  1909. log_warn(LD_GENERAL, "Please upgrade! "
  1910. "This version of Tor (%s) is %s, according to the directory "
  1911. "authorities. Recommended versions are: %s",
  1912. VERSION,
  1913. status == VS_OLD ? "obsolete" : "not recommended",
  1914. recommended);
  1915. have_warned_about_old_version = 1;
  1916. control_event_general_status(LOG_WARN, "DANGEROUS_VERSION "
  1917. "CURRENT=%s REASON=%s RECOMMENDED=\"%s\"",
  1918. VERSION, status == VS_OLD ? "OBSOLETE" : "UNRECOMMENDED",
  1919. recommended);
  1920. }
  1921. }
  1922. }
  1923. /** Given a list <b>routers</b> of routerinfo_t *, update each status field
  1924. * according to our current consensus networkstatus. May re-order
  1925. * <b>routers</b>. */
  1926. void
  1927. routers_update_status_from_consensus_networkstatus(smartlist_t *routers,
  1928. int reset_failures)
  1929. {
  1930. const or_options_t *options = get_options();
  1931. int authdir = authdir_mode_v3(options);
  1932. networkstatus_t *ns = networkstatus_get_latest_consensus();
  1933. if (!ns || !smartlist_len(ns->routerstatus_list))
  1934. return;
  1935. routers_sort_by_identity(routers);
  1936. SMARTLIST_FOREACH_JOIN(ns->routerstatus_list, routerstatus_t *, rs,
  1937. routers, routerinfo_t *, router,
  1938. tor_memcmp(rs->identity_digest,
  1939. router->cache_info.identity_digest, DIGEST_LEN),
  1940. {
  1941. }) {
  1942. /* Is it the same descriptor, or only the same identity? */
  1943. if (tor_memeq(router->cache_info.signed_descriptor_digest,
  1944. rs->descriptor_digest, DIGEST_LEN)) {
  1945. if (ns->valid_until > router->cache_info.last_listed_as_valid_until)
  1946. router->cache_info.last_listed_as_valid_until = ns->valid_until;
  1947. }
  1948. if (authdir) {
  1949. /* If we _are_ an authority, we should check whether this router
  1950. * is one that will cause us to need a reachability test. */
  1951. routerinfo_t *old_router =
  1952. router_get_mutable_by_digest(router->cache_info.identity_digest);
  1953. if (old_router != router) {
  1954. router->needs_retest_if_added =
  1955. dirserv_should_launch_reachability_test(router, old_router);
  1956. }
  1957. }
  1958. if (reset_failures) {
  1959. download_status_reset(&rs->dl_status);
  1960. }
  1961. } SMARTLIST_FOREACH_JOIN_END(rs, router);
  1962. router_dir_info_changed();
  1963. }
  1964. /** Given a list of signed_descriptor_t, update their fields (mainly, when
  1965. * they were last listed) from the most recent consensus. */
  1966. void
  1967. signed_descs_update_status_from_consensus_networkstatus(smartlist_t *descs)
  1968. {
  1969. networkstatus_t *ns = current_ns_consensus;
  1970. if (!ns)
  1971. return;
  1972. if (!ns->desc_digest_map) {
  1973. char dummy[DIGEST_LEN];
  1974. /* instantiates the digest map. */
  1975. memset(dummy, 0, sizeof(dummy));
  1976. router_get_consensus_status_by_descriptor_digest(ns, dummy);
  1977. }
  1978. SMARTLIST_FOREACH(descs, signed_descriptor_t *, d,
  1979. {
  1980. const routerstatus_t *rs = digestmap_get(ns->desc_digest_map,
  1981. d->signed_descriptor_digest);
  1982. if (rs) {
  1983. if (ns->valid_until > d->last_listed_as_valid_until)
  1984. d->last_listed_as_valid_until = ns->valid_until;
  1985. }
  1986. });
  1987. }
  1988. /** Generate networkstatus lines for a single routerstatus_t object, and
  1989. * return the result in a newly allocated string. Used only by controller
  1990. * interface (for now.) */
  1991. char *
  1992. networkstatus_getinfo_helper_single(const routerstatus_t *rs)
  1993. {
  1994. return routerstatus_format_entry(rs, NULL, NULL, NS_CONTROL_PORT, NULL);
  1995. }
  1996. /** Alloc and return a string describing routerstatuses for the most
  1997. * recent info of each router we know about that is of purpose
  1998. * <b>purpose_string</b>. Return NULL if unrecognized purpose.
  1999. *
  2000. * Right now this function is oriented toward listing bridges (you
  2001. * shouldn't use this for general-purpose routers, since those
  2002. * should be listed from the consensus, not from the routers list). */
  2003. char *
  2004. networkstatus_getinfo_by_purpose(const char *purpose_string, time_t now)
  2005. {
  2006. time_t cutoff = now - ROUTER_MAX_AGE_TO_PUBLISH;
  2007. char *answer;
  2008. routerlist_t *rl = router_get_routerlist();
  2009. smartlist_t *statuses;
  2010. uint8_t purpose = router_purpose_from_string(purpose_string);
  2011. routerstatus_t rs;
  2012. int bridge_auth = authdir_mode_bridge(get_options());
  2013. if (purpose == ROUTER_PURPOSE_UNKNOWN) {
  2014. log_info(LD_DIR, "Unrecognized purpose '%s' when listing router statuses.",
  2015. purpose_string);
  2016. return NULL;
  2017. }
  2018. statuses = smartlist_new();
  2019. SMARTLIST_FOREACH_BEGIN(rl->routers, routerinfo_t *, ri) {
  2020. node_t *node = node_get_mutable_by_id(ri->cache_info.identity_digest);
  2021. if (!node)
  2022. continue;
  2023. if (ri->cache_info.published_on < cutoff)
  2024. continue;
  2025. if (ri->purpose != purpose)
  2026. continue;
  2027. if (bridge_auth && ri->purpose == ROUTER_PURPOSE_BRIDGE)
  2028. dirserv_set_router_is_running(ri, now);
  2029. /* then generate and write out status lines for each of them */
  2030. set_routerstatus_from_routerinfo(&rs, node, ri, now, 0);
  2031. smartlist_add(statuses, networkstatus_getinfo_helper_single(&rs));
  2032. } SMARTLIST_FOREACH_END(ri);
  2033. answer = smartlist_join_strings(statuses, "", 0, NULL);
  2034. SMARTLIST_FOREACH(statuses, char *, cp, tor_free(cp));
  2035. smartlist_free(statuses);
  2036. return answer;
  2037. }
  2038. /** Write out router status entries for all our bridge descriptors. */
  2039. void
  2040. networkstatus_dump_bridge_status_to_file(time_t now)
  2041. {
  2042. char *status = networkstatus_getinfo_by_purpose("bridge", now);
  2043. const or_options_t *options = get_options();
  2044. char *fname = NULL;
  2045. char *thresholds = NULL;
  2046. char *published_thresholds_and_status = NULL;
  2047. char published[ISO_TIME_LEN+1];
  2048. const routerinfo_t *me = router_get_my_routerinfo();
  2049. char fingerprint[FINGERPRINT_LEN+1];
  2050. char *fingerprint_line = NULL;
  2051. if (me && crypto_pk_get_fingerprint(me->identity_pkey,
  2052. fingerprint, 0) >= 0) {
  2053. tor_asprintf(&fingerprint_line, "fingerprint %s\n", fingerprint);
  2054. } else {
  2055. log_warn(LD_BUG, "Error computing fingerprint for bridge status.");
  2056. }
  2057. format_iso_time(published, now);
  2058. dirserv_compute_bridge_flag_thresholds();
  2059. thresholds = dirserv_get_flag_thresholds_line();
  2060. tor_asprintf(&published_thresholds_and_status,
  2061. "published %s\nflag-thresholds %s\n%s%s",
  2062. published, thresholds, fingerprint_line ? fingerprint_line : "",
  2063. status);
  2064. tor_asprintf(&fname, "%s"PATH_SEPARATOR"networkstatus-bridges",
  2065. options->DataDirectory);
  2066. write_str_to_file(fname,published_thresholds_and_status,0);
  2067. tor_free(thresholds);
  2068. tor_free(published_thresholds_and_status);
  2069. tor_free(fname);
  2070. tor_free(status);
  2071. tor_free(fingerprint_line);
  2072. }
  2073. /* DOCDOC get_net_param_from_list */
  2074. static int32_t
  2075. get_net_param_from_list(smartlist_t *net_params, const char *param_name,
  2076. int32_t default_val, int32_t min_val, int32_t max_val)
  2077. {
  2078. int32_t res = default_val;
  2079. size_t name_len = strlen(param_name);
  2080. tor_assert(max_val > min_val);
  2081. tor_assert(min_val <= default_val);
  2082. tor_assert(max_val >= default_val);
  2083. SMARTLIST_FOREACH_BEGIN(net_params, const char *, p) {
  2084. if (!strcmpstart(p, param_name) && p[name_len] == '=') {
  2085. int ok=0;
  2086. long v = tor_parse_long(p+name_len+1, 10, INT32_MIN,
  2087. INT32_MAX, &ok, NULL);
  2088. if (ok) {
  2089. res = (int32_t) v;
  2090. break;
  2091. }
  2092. }
  2093. } SMARTLIST_FOREACH_END(p);
  2094. if (res < min_val) {
  2095. log_warn(LD_DIR, "Consensus parameter %s is too small. Got %d, raising to "
  2096. "%d.", param_name, res, min_val);
  2097. res = min_val;
  2098. } else if (res > max_val) {
  2099. log_warn(LD_DIR, "Consensus parameter %s is too large. Got %d, capping to "
  2100. "%d.", param_name, res, max_val);
  2101. res = max_val;
  2102. }
  2103. return res;
  2104. }
  2105. /** Return the value of a integer parameter from the networkstatus <b>ns</b>
  2106. * whose name is <b>param_name</b>. If <b>ns</b> is NULL, try loading the
  2107. * latest consensus ourselves. Return <b>default_val</b> if no latest
  2108. * consensus, or if it has no parameter called <b>param_name</b>.
  2109. * Make sure the value parsed from the consensus is at least
  2110. * <b>min_val</b> and at most <b>max_val</b> and raise/cap the parsed value
  2111. * if necessary. */
  2112. MOCK_IMPL(int32_t,
  2113. networkstatus_get_param, (const networkstatus_t *ns, const char *param_name,
  2114. int32_t default_val, int32_t min_val, int32_t max_val))
  2115. {
  2116. if (!ns) /* if they pass in null, go find it ourselves */
  2117. ns = networkstatus_get_latest_consensus();
  2118. if (!ns || !ns->net_params)
  2119. return default_val;
  2120. return get_net_param_from_list(ns->net_params, param_name,
  2121. default_val, min_val, max_val);
  2122. }
  2123. /**
  2124. * As networkstatus_get_param(), but check torrc_value before checking the
  2125. * consensus. If torrc_value is in-range, then return it instead of the
  2126. * value from the consensus.
  2127. */
  2128. int32_t
  2129. networkstatus_get_overridable_param(const networkstatus_t *ns,
  2130. int32_t torrc_value,
  2131. const char *param_name,
  2132. int32_t default_val,
  2133. int32_t min_val, int32_t max_val)
  2134. {
  2135. if (torrc_value >= min_val && torrc_value <= max_val)
  2136. return torrc_value;
  2137. else
  2138. return networkstatus_get_param(
  2139. ns, param_name, default_val, min_val, max_val);
  2140. }
  2141. /**
  2142. * Retrieve the consensus parameter that governs the
  2143. * fixed-point precision of our network balancing 'bandwidth-weights'
  2144. * (which are themselves integer consensus values). We divide them
  2145. * by this value and ensure they never exceed this value.
  2146. */
  2147. int
  2148. networkstatus_get_weight_scale_param(networkstatus_t *ns)
  2149. {
  2150. return networkstatus_get_param(ns, "bwweightscale",
  2151. BW_WEIGHT_SCALE,
  2152. BW_MIN_WEIGHT_SCALE,
  2153. BW_MAX_WEIGHT_SCALE);
  2154. }
  2155. /** Return the value of a integer bw weight parameter from the networkstatus
  2156. * <b>ns</b> whose name is <b>weight_name</b>. If <b>ns</b> is NULL, try
  2157. * loading the latest consensus ourselves. Return <b>default_val</b> if no
  2158. * latest consensus, or if it has no parameter called <b>weight_name</b>. */
  2159. int32_t
  2160. networkstatus_get_bw_weight(networkstatus_t *ns, const char *weight_name,
  2161. int32_t default_val)
  2162. {
  2163. int32_t param;
  2164. int max;
  2165. if (!ns) /* if they pass in null, go find it ourselves */
  2166. ns = networkstatus_get_latest_consensus();
  2167. if (!ns || !ns->weight_params)
  2168. return default_val;
  2169. max = networkstatus_get_weight_scale_param(ns);
  2170. param = get_net_param_from_list(ns->weight_params, weight_name,
  2171. default_val, -1,
  2172. BW_MAX_WEIGHT_SCALE);
  2173. if (param > max) {
  2174. log_warn(LD_DIR, "Value of consensus weight %s was too large, capping "
  2175. "to %d", weight_name, max);
  2176. param = max;
  2177. }
  2178. return param;
  2179. }
  2180. /** Return the name of the consensus flavor <b>flav</b> as used to identify
  2181. * the flavor in directory documents. */
  2182. const char *
  2183. networkstatus_get_flavor_name(consensus_flavor_t flav)
  2184. {
  2185. switch (flav) {
  2186. case FLAV_NS:
  2187. return "ns";
  2188. case FLAV_MICRODESC:
  2189. return "microdesc";
  2190. default:
  2191. tor_fragile_assert();
  2192. return "??";
  2193. }
  2194. }
  2195. /** Return the consensus_flavor_t value for the flavor called <b>flavname</b>,
  2196. * or -1 if the flavor is not recognized. */
  2197. int
  2198. networkstatus_parse_flavor_name(const char *flavname)
  2199. {
  2200. if (!strcmp(flavname, "ns"))
  2201. return FLAV_NS;
  2202. else if (!strcmp(flavname, "microdesc"))
  2203. return FLAV_MICRODESC;
  2204. else
  2205. return -1;
  2206. }
  2207. /** Return 0 if this routerstatus is obsolete, too new, isn't
  2208. * running, or otherwise not a descriptor that we would make any
  2209. * use of even if we had it. Else return 1. */
  2210. int
  2211. client_would_use_router(const routerstatus_t *rs, time_t now)
  2212. {
  2213. if (!rs->is_flagged_running) {
  2214. /* If we had this router descriptor, we wouldn't even bother using it.
  2215. * (Fetching and storing depends on by we_want_to_fetch_flavor().) */
  2216. return 0;
  2217. }
  2218. if (rs->published_on + OLD_ROUTER_DESC_MAX_AGE < now) {
  2219. /* We'd drop it immediately for being too old. */
  2220. return 0;
  2221. }
  2222. if (!routerstatus_version_supports_extend2_cells(rs, 1)) {
  2223. /* We'd ignore it because it doesn't support EXTEND2 cells.
  2224. * If we don't know the version, download the descriptor so we can
  2225. * check if it supports EXTEND2 cells and ntor. */
  2226. return 0;
  2227. }
  2228. return 1;
  2229. }
  2230. /** If <b>question</b> is a string beginning with "ns/" in a format the
  2231. * control interface expects for a GETINFO question, set *<b>answer</b> to a
  2232. * newly-allocated string containing networkstatus lines for the appropriate
  2233. * ORs. Return 0 on success, -1 on unrecognized question format. */
  2234. int
  2235. getinfo_helper_networkstatus(control_connection_t *conn,
  2236. const char *question, char **answer,
  2237. const char **errmsg)
  2238. {
  2239. const routerstatus_t *status;
  2240. (void) conn;
  2241. if (!networkstatus_get_latest_consensus()) {
  2242. *answer = tor_strdup("");
  2243. return 0;
  2244. }
  2245. if (!strcmp(question, "ns/all")) {
  2246. smartlist_t *statuses = smartlist_new();
  2247. SMARTLIST_FOREACH(networkstatus_get_latest_consensus()->routerstatus_list,
  2248. const routerstatus_t *, rs,
  2249. {
  2250. smartlist_add(statuses, networkstatus_getinfo_helper_single(rs));
  2251. });
  2252. *answer = smartlist_join_strings(statuses, "", 0, NULL);
  2253. SMARTLIST_FOREACH(statuses, char *, cp, tor_free(cp));
  2254. smartlist_free(statuses);
  2255. return 0;
  2256. } else if (!strcmpstart(question, "ns/id/")) {
  2257. char d[DIGEST_LEN];
  2258. const char *q = question + 6;
  2259. if (*q == '$')
  2260. ++q;
  2261. if (base16_decode(d, DIGEST_LEN, q, strlen(q)) != DIGEST_LEN) {
  2262. *errmsg = "Data not decodeable as hex";
  2263. return -1;
  2264. }
  2265. status = router_get_consensus_status_by_id(d);
  2266. } else if (!strcmpstart(question, "ns/name/")) {
  2267. const node_t *n = node_get_by_nickname(question+8, 0);
  2268. status = n ? n->rs : NULL;
  2269. } else if (!strcmpstart(question, "ns/purpose/")) {
  2270. *answer = networkstatus_getinfo_by_purpose(question+11, time(NULL));
  2271. return *answer ? 0 : -1;
  2272. } else if (!strcmp(question, "consensus/packages")) {
  2273. const networkstatus_t *ns = networkstatus_get_latest_consensus();
  2274. if (ns && ns->package_lines)
  2275. *answer = smartlist_join_strings(ns->package_lines, "\n", 0, NULL);
  2276. else
  2277. *errmsg = "No consensus available";
  2278. return *answer ? 0 : -1;
  2279. } else if (!strcmp(question, "consensus/valid-after") ||
  2280. !strcmp(question, "consensus/fresh-until") ||
  2281. !strcmp(question, "consensus/valid-until")) {
  2282. const networkstatus_t *ns = networkstatus_get_latest_consensus();
  2283. if (ns) {
  2284. time_t t;
  2285. if (!strcmp(question, "consensus/valid-after"))
  2286. t = ns->valid_after;
  2287. else if (!strcmp(question, "consensus/fresh-until"))
  2288. t = ns->fresh_until;
  2289. else
  2290. t = ns->valid_until;
  2291. char tbuf[ISO_TIME_LEN+1];
  2292. format_iso_time(tbuf, t);
  2293. *answer = tor_strdup(tbuf);
  2294. } else {
  2295. *errmsg = "No consensus available";
  2296. }
  2297. return *answer ? 0 : -1;
  2298. } else {
  2299. return 0;
  2300. }
  2301. if (status)
  2302. *answer = networkstatus_getinfo_helper_single(status);
  2303. return 0;
  2304. }
  2305. /** Check whether the networkstatus <b>ns</b> lists any protocol
  2306. * versions as "required" or "recommended" that we do not support. If
  2307. * so, set *<b>warning_out</b> to a newly allocated string describing
  2308. * the problem.
  2309. *
  2310. * Return 1 if we should exit, 0 if we should not. */
  2311. int
  2312. networkstatus_check_required_protocols(const networkstatus_t *ns,
  2313. int client_mode,
  2314. char **warning_out)
  2315. {
  2316. const char *func = client_mode ? "client" : "relay";
  2317. const char *required, *recommended;
  2318. char *missing = NULL;
  2319. tor_assert(warning_out);
  2320. if (client_mode) {
  2321. required = ns->required_client_protocols;
  2322. recommended = ns->recommended_client_protocols;
  2323. } else {
  2324. required = ns->required_relay_protocols;
  2325. recommended = ns->recommended_relay_protocols;
  2326. }
  2327. if (!protover_all_supported(required, &missing)) {
  2328. tor_asprintf(warning_out, "At least one protocol listed as required in "
  2329. "the consensus is not supported by this version of Tor. "
  2330. "You should upgrade. This version of Tor will not work as a "
  2331. "%s on the Tor network. The missing protocols are: %s",
  2332. func, missing);
  2333. tor_free(missing);
  2334. return 1;
  2335. }
  2336. if (! protover_all_supported(recommended, &missing)) {
  2337. tor_asprintf(warning_out, "At least one protocol listed as recommended in "
  2338. "the consensus is not supported by this version of Tor. "
  2339. "You should upgrade. This version of Tor will eventually "
  2340. "stop working as a %s on the Tor network. The missing "
  2341. "protocols are: %s",
  2342. func, missing);
  2343. tor_free(missing);
  2344. }
  2345. tor_assert_nonfatal(missing == NULL);
  2346. return 0;
  2347. }
  2348. /** Free all storage held locally in this module. */
  2349. void
  2350. networkstatus_free_all(void)
  2351. {
  2352. int i;
  2353. networkstatus_vote_free(current_ns_consensus);
  2354. networkstatus_vote_free(current_md_consensus);
  2355. current_md_consensus = current_ns_consensus = NULL;
  2356. for (i=0; i < N_CONSENSUS_FLAVORS; ++i) {
  2357. consensus_waiting_for_certs_t *waiting = &consensus_waiting_for_certs[i];
  2358. if (waiting->consensus) {
  2359. networkstatus_vote_free(waiting->consensus);
  2360. waiting->consensus = NULL;
  2361. }
  2362. tor_free(waiting->body);
  2363. }
  2364. }