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