policies.c 102 KB

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  1. /* Copyright (c) 2001-2004, Roger Dingledine.
  2. * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
  3. * Copyright (c) 2007-2016, The Tor Project, Inc. */
  4. /* See LICENSE for licensing information */
  5. /**
  6. * \file policies.c
  7. * \brief Code to parse and use address policies and exit policies.
  8. **/
  9. #define POLICIES_PRIVATE
  10. #include "or.h"
  11. #include "config.h"
  12. #include "dirserv.h"
  13. #include "networkstatus.h"
  14. #include "nodelist.h"
  15. #include "policies.h"
  16. #include "router.h"
  17. #include "routerparse.h"
  18. #include "geoip.h"
  19. #include "ht.h"
  20. /** Policy that addresses for incoming SOCKS connections must match. */
  21. static smartlist_t *socks_policy = NULL;
  22. /** Policy that addresses for incoming directory connections must match. */
  23. static smartlist_t *dir_policy = NULL;
  24. /** Policy that addresses for incoming router descriptors must match in order
  25. * to be published by us. */
  26. static smartlist_t *authdir_reject_policy = NULL;
  27. /** Policy that addresses for incoming router descriptors must match in order
  28. * to be marked as valid in our networkstatus. */
  29. static smartlist_t *authdir_invalid_policy = NULL;
  30. /** Policy that addresses for incoming router descriptors must <b>not</b>
  31. * match in order to not be marked as BadExit. */
  32. static smartlist_t *authdir_badexit_policy = NULL;
  33. /** Parsed addr_policy_t describing which addresses we believe we can start
  34. * circuits at. */
  35. static smartlist_t *reachable_or_addr_policy = NULL;
  36. /** Parsed addr_policy_t describing which addresses we believe we can connect
  37. * to directories at. */
  38. static smartlist_t *reachable_dir_addr_policy = NULL;
  39. /** Element of an exit policy summary */
  40. typedef struct policy_summary_item_t {
  41. uint16_t prt_min; /**< Lowest port number to accept/reject. */
  42. uint16_t prt_max; /**< Highest port number to accept/reject. */
  43. uint64_t reject_count; /**< Number of IP-Addresses that are rejected to
  44. this port range. */
  45. unsigned int accepted:1; /** Has this port already been accepted */
  46. } policy_summary_item_t;
  47. /** Private networks. This list is used in two places, once to expand the
  48. * "private" keyword when parsing our own exit policy, secondly to ignore
  49. * just such networks when building exit policy summaries. It is important
  50. * that all authorities agree on that list when creating summaries, so don't
  51. * just change this without a proper migration plan and a proposal and stuff.
  52. */
  53. static const char *private_nets[] = {
  54. "0.0.0.0/8", "169.254.0.0/16",
  55. "127.0.0.0/8", "192.168.0.0/16", "10.0.0.0/8", "172.16.0.0/12",
  56. "[::]/8",
  57. "[fc00::]/7", "[fe80::]/10", "[fec0::]/10", "[ff00::]/8", "[::]/127",
  58. NULL
  59. };
  60. static int policies_parse_exit_policy_internal(
  61. config_line_t *cfg,
  62. smartlist_t **dest,
  63. int ipv6_exit,
  64. int rejectprivate,
  65. const smartlist_t *configured_addresses,
  66. int reject_interface_addresses,
  67. int reject_configured_port_addresses,
  68. int add_default_policy);
  69. /** Replace all "private" entries in *<b>policy</b> with their expanded
  70. * equivalents. */
  71. void
  72. policy_expand_private(smartlist_t **policy)
  73. {
  74. uint16_t port_min, port_max;
  75. int i;
  76. smartlist_t *tmp;
  77. if (!*policy) /*XXXX disallow NULL policies? */
  78. return;
  79. tmp = smartlist_new();
  80. SMARTLIST_FOREACH_BEGIN(*policy, addr_policy_t *, p) {
  81. if (! p->is_private) {
  82. smartlist_add(tmp, p);
  83. continue;
  84. }
  85. for (i = 0; private_nets[i]; ++i) {
  86. addr_policy_t newpolicy;
  87. memcpy(&newpolicy, p, sizeof(addr_policy_t));
  88. newpolicy.is_private = 0;
  89. newpolicy.is_canonical = 0;
  90. if (tor_addr_parse_mask_ports(private_nets[i], 0,
  91. &newpolicy.addr,
  92. &newpolicy.maskbits, &port_min, &port_max)<0) {
  93. tor_assert_unreached();
  94. }
  95. smartlist_add(tmp, addr_policy_get_canonical_entry(&newpolicy));
  96. }
  97. addr_policy_free(p);
  98. } SMARTLIST_FOREACH_END(p);
  99. smartlist_free(*policy);
  100. *policy = tmp;
  101. }
  102. /** Expand each of the AF_UNSPEC elements in *<b>policy</b> (which indicate
  103. * protocol-neutral wildcards) into a pair of wildcard elements: one IPv4-
  104. * specific and one IPv6-specific. */
  105. void
  106. policy_expand_unspec(smartlist_t **policy)
  107. {
  108. smartlist_t *tmp;
  109. if (!*policy)
  110. return;
  111. tmp = smartlist_new();
  112. SMARTLIST_FOREACH_BEGIN(*policy, addr_policy_t *, p) {
  113. sa_family_t family = tor_addr_family(&p->addr);
  114. if (family == AF_INET6 || family == AF_INET || p->is_private) {
  115. smartlist_add(tmp, p);
  116. } else if (family == AF_UNSPEC) {
  117. addr_policy_t newpolicy_ipv4;
  118. addr_policy_t newpolicy_ipv6;
  119. memcpy(&newpolicy_ipv4, p, sizeof(addr_policy_t));
  120. memcpy(&newpolicy_ipv6, p, sizeof(addr_policy_t));
  121. newpolicy_ipv4.is_canonical = 0;
  122. newpolicy_ipv6.is_canonical = 0;
  123. if (p->maskbits != 0) {
  124. log_warn(LD_BUG, "AF_UNSPEC policy with maskbits==%d", p->maskbits);
  125. newpolicy_ipv4.maskbits = 0;
  126. newpolicy_ipv6.maskbits = 0;
  127. }
  128. tor_addr_from_ipv4h(&newpolicy_ipv4.addr, 0);
  129. tor_addr_from_ipv6_bytes(&newpolicy_ipv6.addr,
  130. "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0");
  131. smartlist_add(tmp, addr_policy_get_canonical_entry(&newpolicy_ipv4));
  132. smartlist_add(tmp, addr_policy_get_canonical_entry(&newpolicy_ipv6));
  133. addr_policy_free(p);
  134. } else {
  135. log_warn(LD_BUG, "Funny-looking address policy with family %d", family);
  136. smartlist_add(tmp, p);
  137. }
  138. } SMARTLIST_FOREACH_END(p);
  139. smartlist_free(*policy);
  140. *policy = tmp;
  141. }
  142. /**
  143. * Given a linked list of config lines containing "accept[6]" and "reject[6]"
  144. * tokens, parse them and append the result to <b>dest</b>. Return -1
  145. * if any tokens are malformed (and don't append any), else return 0.
  146. *
  147. * If <b>assume_action</b> is nonnegative, then insert its action
  148. * (ADDR_POLICY_ACCEPT or ADDR_POLICY_REJECT) for items that specify no
  149. * action.
  150. */
  151. static int
  152. parse_addr_policy(config_line_t *cfg, smartlist_t **dest,
  153. int assume_action)
  154. {
  155. smartlist_t *result;
  156. smartlist_t *entries;
  157. addr_policy_t *item;
  158. int malformed_list;
  159. int r = 0;
  160. if (!cfg)
  161. return 0;
  162. result = smartlist_new();
  163. entries = smartlist_new();
  164. for (; cfg; cfg = cfg->next) {
  165. smartlist_split_string(entries, cfg->value, ",",
  166. SPLIT_SKIP_SPACE|SPLIT_IGNORE_BLANK, 0);
  167. SMARTLIST_FOREACH_BEGIN(entries, const char *, ent) {
  168. log_debug(LD_CONFIG,"Adding new entry '%s'",ent);
  169. malformed_list = 0;
  170. item = router_parse_addr_policy_item_from_string(ent, assume_action,
  171. &malformed_list);
  172. if (item) {
  173. smartlist_add(result, item);
  174. } else if (malformed_list) {
  175. /* the error is so severe the entire list should be discarded */
  176. log_warn(LD_CONFIG, "Malformed policy '%s'. Discarding entire policy "
  177. "list.", ent);
  178. r = -1;
  179. } else {
  180. /* the error is minor: don't add the item, but keep processing the
  181. * rest of the policies in the list */
  182. log_debug(LD_CONFIG, "Ignored policy '%s' due to non-fatal error. "
  183. "The remainder of the policy list will be used.",
  184. ent);
  185. }
  186. } SMARTLIST_FOREACH_END(ent);
  187. SMARTLIST_FOREACH(entries, char *, ent, tor_free(ent));
  188. smartlist_clear(entries);
  189. }
  190. smartlist_free(entries);
  191. if (r == -1) {
  192. addr_policy_list_free(result);
  193. } else {
  194. policy_expand_private(&result);
  195. policy_expand_unspec(&result);
  196. if (*dest) {
  197. smartlist_add_all(*dest, result);
  198. smartlist_free(result);
  199. } else {
  200. *dest = result;
  201. }
  202. }
  203. return r;
  204. }
  205. /** Helper: parse the Reachable(Dir|OR)?Addresses fields into
  206. * reachable_(or|dir)_addr_policy. The options should already have
  207. * been validated by validate_addr_policies.
  208. */
  209. static int
  210. parse_reachable_addresses(void)
  211. {
  212. const or_options_t *options = get_options();
  213. int ret = 0;
  214. if (options->ReachableDirAddresses &&
  215. options->ReachableORAddresses &&
  216. options->ReachableAddresses) {
  217. log_warn(LD_CONFIG,
  218. "Both ReachableDirAddresses and ReachableORAddresses are set. "
  219. "ReachableAddresses setting will be ignored.");
  220. }
  221. addr_policy_list_free(reachable_or_addr_policy);
  222. reachable_or_addr_policy = NULL;
  223. if (!options->ReachableORAddresses && options->ReachableAddresses)
  224. log_info(LD_CONFIG,
  225. "Using ReachableAddresses as ReachableORAddresses.");
  226. if (parse_addr_policy(options->ReachableORAddresses ?
  227. options->ReachableORAddresses :
  228. options->ReachableAddresses,
  229. &reachable_or_addr_policy, ADDR_POLICY_ACCEPT)) {
  230. log_warn(LD_CONFIG,
  231. "Error parsing Reachable%sAddresses entry; ignoring.",
  232. options->ReachableORAddresses ? "OR" : "");
  233. ret = -1;
  234. }
  235. addr_policy_list_free(reachable_dir_addr_policy);
  236. reachable_dir_addr_policy = NULL;
  237. if (!options->ReachableDirAddresses && options->ReachableAddresses)
  238. log_info(LD_CONFIG,
  239. "Using ReachableAddresses as ReachableDirAddresses");
  240. if (parse_addr_policy(options->ReachableDirAddresses ?
  241. options->ReachableDirAddresses :
  242. options->ReachableAddresses,
  243. &reachable_dir_addr_policy, ADDR_POLICY_ACCEPT)) {
  244. if (options->ReachableDirAddresses)
  245. log_warn(LD_CONFIG,
  246. "Error parsing ReachableDirAddresses entry; ignoring.");
  247. ret = -1;
  248. }
  249. /* We ignore ReachableAddresses for relays */
  250. if (!server_mode(options)) {
  251. if ((reachable_or_addr_policy
  252. && policy_is_reject_star(reachable_or_addr_policy, AF_UNSPEC))
  253. || (reachable_dir_addr_policy
  254. && policy_is_reject_star(reachable_dir_addr_policy, AF_UNSPEC))) {
  255. log_warn(LD_CONFIG, "Tor cannot connect to the Internet if "
  256. "ReachableAddresses, ReachableORAddresses, or "
  257. "ReachableDirAddresses reject all addresses. Please accept "
  258. "some addresses in these options.");
  259. } else if (options->ClientUseIPv4 == 1
  260. && ((reachable_or_addr_policy
  261. && policy_is_reject_star(reachable_or_addr_policy, AF_INET))
  262. || (reachable_dir_addr_policy
  263. && policy_is_reject_star(reachable_dir_addr_policy, AF_INET)))) {
  264. log_warn(LD_CONFIG, "You have set ClientUseIPv4 1, but "
  265. "ReachableAddresses, ReachableORAddresses, or "
  266. "ReachableDirAddresses reject all IPv4 addresses. "
  267. "Tor will not connect using IPv4.");
  268. } else if (fascist_firewall_use_ipv6(options)
  269. && ((reachable_or_addr_policy
  270. && policy_is_reject_star(reachable_or_addr_policy, AF_INET6))
  271. || (reachable_dir_addr_policy
  272. && policy_is_reject_star(reachable_dir_addr_policy, AF_INET6)))) {
  273. log_warn(LD_CONFIG, "You have configured tor to use IPv6 "
  274. "(ClientUseIPv6 1 or UseBridges 1), but "
  275. "ReachableAddresses, ReachableORAddresses, or "
  276. "ReachableDirAddresses reject all IPv6 addresses. "
  277. "Tor will not connect using IPv6.");
  278. }
  279. }
  280. return ret;
  281. }
  282. /* Return true iff ClientUseIPv4 0 or ClientUseIPv6 0 might block any OR or Dir
  283. * address:port combination. */
  284. static int
  285. firewall_is_fascist_impl(void)
  286. {
  287. const or_options_t *options = get_options();
  288. /* Assume every non-bridge relay has an IPv4 address.
  289. * Clients which use bridges may only know the IPv6 address of their
  290. * bridge. */
  291. return (options->ClientUseIPv4 == 0
  292. || (!fascist_firewall_use_ipv6(options)
  293. && options->UseBridges == 1));
  294. }
  295. /** Return true iff the firewall options, including ClientUseIPv4 0 and
  296. * ClientUseIPv6 0, might block any OR address:port combination.
  297. * Address preferences may still change which address is selected even if
  298. * this function returns false.
  299. */
  300. int
  301. firewall_is_fascist_or(void)
  302. {
  303. return (reachable_or_addr_policy != NULL || firewall_is_fascist_impl());
  304. }
  305. /** Return true iff the firewall options, including ClientUseIPv4 0 and
  306. * ClientUseIPv6 0, might block any Dir address:port combination.
  307. * Address preferences may still change which address is selected even if
  308. * this function returns false.
  309. */
  310. int
  311. firewall_is_fascist_dir(void)
  312. {
  313. return (reachable_dir_addr_policy != NULL || firewall_is_fascist_impl());
  314. }
  315. /** Return true iff <b>policy</b> (possibly NULL) will allow a
  316. * connection to <b>addr</b>:<b>port</b>.
  317. */
  318. static int
  319. addr_policy_permits_tor_addr(const tor_addr_t *addr, uint16_t port,
  320. smartlist_t *policy)
  321. {
  322. addr_policy_result_t p;
  323. p = compare_tor_addr_to_addr_policy(addr, port, policy);
  324. switch (p) {
  325. case ADDR_POLICY_PROBABLY_ACCEPTED:
  326. case ADDR_POLICY_ACCEPTED:
  327. return 1;
  328. case ADDR_POLICY_PROBABLY_REJECTED:
  329. case ADDR_POLICY_REJECTED:
  330. return 0;
  331. default:
  332. log_warn(LD_BUG, "Unexpected result: %d", (int)p);
  333. return 0;
  334. }
  335. }
  336. /** Return true iff <b> policy</b> (possibly NULL) will allow a connection to
  337. * <b>addr</b>:<b>port</b>. <b>addr</b> is an IPv4 address given in host
  338. * order. */
  339. /* XXXX deprecate when possible. */
  340. static int
  341. addr_policy_permits_address(uint32_t addr, uint16_t port,
  342. smartlist_t *policy)
  343. {
  344. tor_addr_t a;
  345. tor_addr_from_ipv4h(&a, addr);
  346. return addr_policy_permits_tor_addr(&a, port, policy);
  347. }
  348. /** Return true iff we think our firewall will let us make a connection to
  349. * addr:port.
  350. *
  351. * If we are configured as a server, ignore any address family preference and
  352. * just use IPv4.
  353. * Otherwise:
  354. * - return false for all IPv4 addresses:
  355. * - if ClientUseIPv4 is 0, or
  356. * if pref_only and pref_ipv6 are both true;
  357. * - return false for all IPv6 addresses:
  358. * - if fascist_firewall_use_ipv6() is 0, or
  359. * - if pref_only is true and pref_ipv6 is false.
  360. *
  361. * Return false if addr is NULL or tor_addr_is_null(), or if port is 0. */
  362. STATIC int
  363. fascist_firewall_allows_address(const tor_addr_t *addr,
  364. uint16_t port,
  365. smartlist_t *firewall_policy,
  366. int pref_only, int pref_ipv6)
  367. {
  368. const or_options_t *options = get_options();
  369. const int client_mode = !server_mode(options);
  370. if (!addr || tor_addr_is_null(addr) || !port) {
  371. return 0;
  372. }
  373. /* Clients stop using IPv4 if it's disabled. In most cases, clients also
  374. * stop using IPv4 if it's not preferred.
  375. * Servers must have IPv4 enabled and preferred. */
  376. if (tor_addr_family(addr) == AF_INET && client_mode &&
  377. (!options->ClientUseIPv4 || (pref_only && pref_ipv6))) {
  378. return 0;
  379. }
  380. /* Clients and Servers won't use IPv6 unless it's enabled (and in most
  381. * cases, IPv6 must also be preferred before it will be used). */
  382. if (tor_addr_family(addr) == AF_INET6 &&
  383. (!fascist_firewall_use_ipv6(options) || (pref_only && !pref_ipv6))) {
  384. return 0;
  385. }
  386. return addr_policy_permits_tor_addr(addr, port,
  387. firewall_policy);
  388. }
  389. /** Is this client configured to use IPv6?
  390. * Use node_ipv6_or/dir_preferred() when checking a specific node and OR/Dir
  391. * port: it supports bridge client per-node IPv6 preferences.
  392. */
  393. int
  394. fascist_firewall_use_ipv6(const or_options_t *options)
  395. {
  396. /* Clients use IPv6 if it's set, or they use bridges, or they don't use
  397. * IPv4 */
  398. return (options->ClientUseIPv6 == 1 || options->UseBridges == 1
  399. || options->ClientUseIPv4 == 0);
  400. }
  401. /** Do we prefer to connect to IPv6, ignoring ClientPreferIPv6ORPort and
  402. * ClientPreferIPv6DirPort?
  403. * If we're unsure, return -1, otherwise, return 1 for IPv6 and 0 for IPv4.
  404. */
  405. static int
  406. fascist_firewall_prefer_ipv6_impl(const or_options_t *options)
  407. {
  408. /*
  409. Cheap implementation of config options ClientUseIPv4 & ClientUseIPv6 --
  410. If we're a server or IPv6 is disabled, use IPv4.
  411. If IPv4 is disabled, use IPv6.
  412. */
  413. if (server_mode(options) || !fascist_firewall_use_ipv6(options)) {
  414. return 0;
  415. }
  416. if (!options->ClientUseIPv4) {
  417. return 1;
  418. }
  419. return -1;
  420. }
  421. /** Do we prefer to connect to IPv6 ORPorts?
  422. * Use node_ipv6_or_preferred() whenever possible: it supports bridge client
  423. * per-node IPv6 preferences.
  424. */
  425. int
  426. fascist_firewall_prefer_ipv6_orport(const or_options_t *options)
  427. {
  428. int pref_ipv6 = fascist_firewall_prefer_ipv6_impl(options);
  429. if (pref_ipv6 >= 0) {
  430. return pref_ipv6;
  431. }
  432. /* We can use both IPv4 and IPv6 - which do we prefer? */
  433. if (options->ClientPreferIPv6ORPort == 1) {
  434. return 1;
  435. }
  436. return 0;
  437. }
  438. /** Do we prefer to connect to IPv6 DirPorts?
  439. *
  440. * (node_ipv6_dir_preferred() doesn't support bridge client per-node IPv6
  441. * preferences. There's no reason to use it instead of this function.)
  442. */
  443. int
  444. fascist_firewall_prefer_ipv6_dirport(const or_options_t *options)
  445. {
  446. int pref_ipv6 = fascist_firewall_prefer_ipv6_impl(options);
  447. if (pref_ipv6 >= 0) {
  448. return pref_ipv6;
  449. }
  450. /* We can use both IPv4 and IPv6 - which do we prefer? */
  451. if (options->ClientPreferIPv6DirPort == 1) {
  452. return 1;
  453. }
  454. return 0;
  455. }
  456. /** Return true iff we think our firewall will let us make a connection to
  457. * addr:port. Uses ReachableORAddresses or ReachableDirAddresses based on
  458. * fw_connection.
  459. * If pref_only is true, return true if addr is in the client's preferred
  460. * address family, which is IPv6 if pref_ipv6 is true, and IPv4 otherwise.
  461. * If pref_only is false, ignore pref_ipv6, and return true if addr is allowed.
  462. */
  463. int
  464. fascist_firewall_allows_address_addr(const tor_addr_t *addr, uint16_t port,
  465. firewall_connection_t fw_connection,
  466. int pref_only, int pref_ipv6)
  467. {
  468. if (fw_connection == FIREWALL_OR_CONNECTION) {
  469. return fascist_firewall_allows_address(addr, port,
  470. reachable_or_addr_policy,
  471. pref_only, pref_ipv6);
  472. } else if (fw_connection == FIREWALL_DIR_CONNECTION) {
  473. return fascist_firewall_allows_address(addr, port,
  474. reachable_dir_addr_policy,
  475. pref_only, pref_ipv6);
  476. } else {
  477. log_warn(LD_BUG, "Bad firewall_connection_t value %d.",
  478. fw_connection);
  479. return 0;
  480. }
  481. }
  482. /** Return true iff we think our firewall will let us make a connection to
  483. * addr:port (ap). Uses ReachableORAddresses or ReachableDirAddresses based on
  484. * fw_connection.
  485. * pref_only and pref_ipv6 work as in fascist_firewall_allows_address_addr().
  486. */
  487. static int
  488. fascist_firewall_allows_address_ap(const tor_addr_port_t *ap,
  489. firewall_connection_t fw_connection,
  490. int pref_only, int pref_ipv6)
  491. {
  492. tor_assert(ap);
  493. return fascist_firewall_allows_address_addr(&ap->addr, ap->port,
  494. fw_connection, pref_only,
  495. pref_ipv6);
  496. }
  497. /* Return true iff we think our firewall will let us make a connection to
  498. * ipv4h_or_addr:ipv4_or_port. ipv4h_or_addr is interpreted in host order.
  499. * Uses ReachableORAddresses or ReachableDirAddresses based on
  500. * fw_connection.
  501. * pref_only and pref_ipv6 work as in fascist_firewall_allows_address_addr().
  502. */
  503. static int
  504. fascist_firewall_allows_address_ipv4h(uint32_t ipv4h_or_addr,
  505. uint16_t ipv4_or_port,
  506. firewall_connection_t fw_connection,
  507. int pref_only, int pref_ipv6)
  508. {
  509. tor_addr_t ipv4_or_addr;
  510. tor_addr_from_ipv4h(&ipv4_or_addr, ipv4h_or_addr);
  511. return fascist_firewall_allows_address_addr(&ipv4_or_addr, ipv4_or_port,
  512. fw_connection, pref_only,
  513. pref_ipv6);
  514. }
  515. /** Return true iff we think our firewall will let us make a connection to
  516. * ipv4h_addr/ipv6_addr. Uses ipv4_orport/ipv6_orport/ReachableORAddresses or
  517. * ipv4_dirport/ipv6_dirport/ReachableDirAddresses based on IPv4/IPv6 and
  518. * <b>fw_connection</b>.
  519. * pref_only and pref_ipv6 work as in fascist_firewall_allows_address_addr().
  520. */
  521. static int
  522. fascist_firewall_allows_base(uint32_t ipv4h_addr, uint16_t ipv4_orport,
  523. uint16_t ipv4_dirport,
  524. const tor_addr_t *ipv6_addr, uint16_t ipv6_orport,
  525. uint16_t ipv6_dirport,
  526. firewall_connection_t fw_connection,
  527. int pref_only, int pref_ipv6)
  528. {
  529. if (fascist_firewall_allows_address_ipv4h(ipv4h_addr,
  530. (fw_connection == FIREWALL_OR_CONNECTION
  531. ? ipv4_orport
  532. : ipv4_dirport),
  533. fw_connection,
  534. pref_only, pref_ipv6)) {
  535. return 1;
  536. }
  537. if (fascist_firewall_allows_address_addr(ipv6_addr,
  538. (fw_connection == FIREWALL_OR_CONNECTION
  539. ? ipv6_orport
  540. : ipv6_dirport),
  541. fw_connection,
  542. pref_only, pref_ipv6)) {
  543. return 1;
  544. }
  545. return 0;
  546. }
  547. /** Like fascist_firewall_allows_base(), but takes ri. */
  548. static int
  549. fascist_firewall_allows_ri_impl(const routerinfo_t *ri,
  550. firewall_connection_t fw_connection,
  551. int pref_only, int pref_ipv6)
  552. {
  553. if (!ri) {
  554. return 0;
  555. }
  556. /* Assume IPv4 and IPv6 DirPorts are the same */
  557. return fascist_firewall_allows_base(ri->addr, ri->or_port, ri->dir_port,
  558. &ri->ipv6_addr, ri->ipv6_orport,
  559. ri->dir_port, fw_connection, pref_only,
  560. pref_ipv6);
  561. }
  562. /** Like fascist_firewall_allows_rs, but takes pref_ipv6. */
  563. static int
  564. fascist_firewall_allows_rs_impl(const routerstatus_t *rs,
  565. firewall_connection_t fw_connection,
  566. int pref_only, int pref_ipv6)
  567. {
  568. if (!rs) {
  569. return 0;
  570. }
  571. /* Assume IPv4 and IPv6 DirPorts are the same */
  572. return fascist_firewall_allows_base(rs->addr, rs->or_port, rs->dir_port,
  573. &rs->ipv6_addr, rs->ipv6_orport,
  574. rs->dir_port, fw_connection, pref_only,
  575. pref_ipv6);
  576. }
  577. /** Like fascist_firewall_allows_base(), but takes rs.
  578. * When rs is a fake_status from a dir_server_t, it can have a reachable
  579. * address, even when the corresponding node does not.
  580. * nodes can be missing addresses when there's no consensus (IPv4 and IPv6),
  581. * or when there is a microdescriptor consensus, but no microdescriptors
  582. * (microdescriptors have IPv6, the microdesc consensus does not). */
  583. int
  584. fascist_firewall_allows_rs(const routerstatus_t *rs,
  585. firewall_connection_t fw_connection, int pref_only)
  586. {
  587. if (!rs) {
  588. return 0;
  589. }
  590. /* We don't have access to the node-specific IPv6 preference, so use the
  591. * generic IPv6 preference instead. */
  592. const or_options_t *options = get_options();
  593. int pref_ipv6 = (fw_connection == FIREWALL_OR_CONNECTION
  594. ? fascist_firewall_prefer_ipv6_orport(options)
  595. : fascist_firewall_prefer_ipv6_dirport(options));
  596. return fascist_firewall_allows_rs_impl(rs, fw_connection, pref_only,
  597. pref_ipv6);
  598. }
  599. /** Return true iff we think our firewall will let us make a connection to
  600. * ipv6_addr:ipv6_orport based on ReachableORAddresses.
  601. * If <b>fw_connection</b> is FIREWALL_DIR_CONNECTION, returns 0.
  602. * pref_only and pref_ipv6 work as in fascist_firewall_allows_address_addr().
  603. */
  604. static int
  605. fascist_firewall_allows_md_impl(const microdesc_t *md,
  606. firewall_connection_t fw_connection,
  607. int pref_only, int pref_ipv6)
  608. {
  609. if (!md) {
  610. return 0;
  611. }
  612. /* Can't check dirport, it doesn't have one */
  613. if (fw_connection == FIREWALL_DIR_CONNECTION) {
  614. return 0;
  615. }
  616. /* Also can't check IPv4, doesn't have that either */
  617. return fascist_firewall_allows_address_addr(&md->ipv6_addr, md->ipv6_orport,
  618. fw_connection, pref_only,
  619. pref_ipv6);
  620. }
  621. /** Like fascist_firewall_allows_base(), but takes node, and looks up pref_ipv6
  622. * from node_ipv6_or/dir_preferred(). */
  623. int
  624. fascist_firewall_allows_node(const node_t *node,
  625. firewall_connection_t fw_connection,
  626. int pref_only)
  627. {
  628. if (!node) {
  629. return 0;
  630. }
  631. node_assert_ok(node);
  632. const int pref_ipv6 = (fw_connection == FIREWALL_OR_CONNECTION
  633. ? node_ipv6_or_preferred(node)
  634. : node_ipv6_dir_preferred(node));
  635. /* Sometimes, the rs is missing the IPv6 address info, and we need to go
  636. * all the way to the md */
  637. if (node->ri && fascist_firewall_allows_ri_impl(node->ri, fw_connection,
  638. pref_only, pref_ipv6)) {
  639. return 1;
  640. } else if (node->rs && fascist_firewall_allows_rs_impl(node->rs,
  641. fw_connection,
  642. pref_only,
  643. pref_ipv6)) {
  644. return 1;
  645. } else if (node->md && fascist_firewall_allows_md_impl(node->md,
  646. fw_connection,
  647. pref_only,
  648. pref_ipv6)) {
  649. return 1;
  650. } else {
  651. /* If we know nothing, assume it's unreachable, we'll never get an address
  652. * to connect to. */
  653. return 0;
  654. }
  655. }
  656. /** Like fascist_firewall_allows_rs(), but takes ds. */
  657. int
  658. fascist_firewall_allows_dir_server(const dir_server_t *ds,
  659. firewall_connection_t fw_connection,
  660. int pref_only)
  661. {
  662. if (!ds) {
  663. return 0;
  664. }
  665. /* A dir_server_t always has a fake_status. As long as it has the same
  666. * addresses/ports in both fake_status and dir_server_t, this works fine.
  667. * (See #17867.)
  668. * fascist_firewall_allows_rs only checks the addresses in fake_status. */
  669. return fascist_firewall_allows_rs(&ds->fake_status, fw_connection,
  670. pref_only);
  671. }
  672. /** If a and b are both valid and allowed by fw_connection,
  673. * choose one based on want_a and return it.
  674. * Otherwise, return whichever is allowed.
  675. * Otherwise, return NULL.
  676. * pref_only and pref_ipv6 work as in fascist_firewall_allows_address_addr().
  677. */
  678. static const tor_addr_port_t *
  679. fascist_firewall_choose_address_impl(const tor_addr_port_t *a,
  680. const tor_addr_port_t *b,
  681. int want_a,
  682. firewall_connection_t fw_connection,
  683. int pref_only, int pref_ipv6)
  684. {
  685. const tor_addr_port_t *use_a = NULL;
  686. const tor_addr_port_t *use_b = NULL;
  687. if (fascist_firewall_allows_address_ap(a, fw_connection, pref_only,
  688. pref_ipv6)) {
  689. use_a = a;
  690. }
  691. if (fascist_firewall_allows_address_ap(b, fw_connection, pref_only,
  692. pref_ipv6)) {
  693. use_b = b;
  694. }
  695. /* If both are allowed */
  696. if (use_a && use_b) {
  697. /* Choose a if we want it */
  698. return (want_a ? use_a : use_b);
  699. } else {
  700. /* Choose a if we have it */
  701. return (use_a ? use_a : use_b);
  702. }
  703. }
  704. /** If a and b are both valid and preferred by fw_connection,
  705. * choose one based on want_a and return it.
  706. * Otherwise, return whichever is preferred.
  707. * If neither are preferred, and pref_only is false:
  708. * - If a and b are both allowed by fw_connection,
  709. * choose one based on want_a and return it.
  710. * - Otherwise, return whichever is preferred.
  711. * Otherwise, return NULL. */
  712. STATIC const tor_addr_port_t *
  713. fascist_firewall_choose_address(const tor_addr_port_t *a,
  714. const tor_addr_port_t *b,
  715. int want_a,
  716. firewall_connection_t fw_connection,
  717. int pref_only, int pref_ipv6)
  718. {
  719. const tor_addr_port_t *pref = fascist_firewall_choose_address_impl(
  720. a, b, want_a,
  721. fw_connection,
  722. 1, pref_ipv6);
  723. if (pref_only || pref) {
  724. /* If there is a preferred address, use it. If we can only use preferred
  725. * addresses, and neither address is preferred, pref will be NULL, and we
  726. * want to return NULL, so return it. */
  727. return pref;
  728. } else {
  729. /* If there's no preferred address, and we can return addresses that are
  730. * not preferred, use an address that's allowed */
  731. return fascist_firewall_choose_address_impl(a, b, want_a, fw_connection,
  732. 0, pref_ipv6);
  733. }
  734. }
  735. /** Copy an address and port into <b>ap</b> that we think our firewall will
  736. * let us connect to. Uses ipv4_addr/ipv6_addr and
  737. * ipv4_orport/ipv6_orport/ReachableORAddresses or
  738. * ipv4_dirport/ipv6_dirport/ReachableDirAddresses based on IPv4/IPv6 and
  739. * <b>fw_connection</b>.
  740. * If pref_only, only choose preferred addresses. In either case, choose
  741. * a preferred address before an address that's not preferred.
  742. * If both addresses could be chosen (they are both preferred or both allowed)
  743. * choose IPv6 if pref_ipv6 is true, otherwise choose IPv4.
  744. * If neither address is chosen, return 0, else return 1. */
  745. static int
  746. fascist_firewall_choose_address_base(const tor_addr_t *ipv4_addr,
  747. uint16_t ipv4_orport,
  748. uint16_t ipv4_dirport,
  749. const tor_addr_t *ipv6_addr,
  750. uint16_t ipv6_orport,
  751. uint16_t ipv6_dirport,
  752. firewall_connection_t fw_connection,
  753. int pref_only,
  754. int pref_ipv6,
  755. tor_addr_port_t* ap)
  756. {
  757. const tor_addr_port_t *result = NULL;
  758. const int want_ipv4 = !pref_ipv6;
  759. tor_assert(ipv6_addr);
  760. tor_assert(ap);
  761. tor_addr_port_t ipv4_ap;
  762. tor_addr_copy(&ipv4_ap.addr, ipv4_addr);
  763. ipv4_ap.port = (fw_connection == FIREWALL_OR_CONNECTION
  764. ? ipv4_orport
  765. : ipv4_dirport);
  766. tor_addr_port_t ipv6_ap;
  767. tor_addr_copy(&ipv6_ap.addr, ipv6_addr);
  768. ipv6_ap.port = (fw_connection == FIREWALL_OR_CONNECTION
  769. ? ipv6_orport
  770. : ipv6_dirport);
  771. result = fascist_firewall_choose_address(&ipv4_ap, &ipv6_ap,
  772. want_ipv4,
  773. fw_connection, pref_only,
  774. pref_ipv6);
  775. if (result) {
  776. tor_addr_copy(&ap->addr, &result->addr);
  777. ap->port = result->port;
  778. return 1;
  779. } else {
  780. return 0;
  781. }
  782. }
  783. /** Like fascist_firewall_choose_address_base(), but takes a host-order IPv4
  784. * address as the first parameter. */
  785. static int
  786. fascist_firewall_choose_address_ipv4h(uint32_t ipv4h_addr,
  787. uint16_t ipv4_orport,
  788. uint16_t ipv4_dirport,
  789. const tor_addr_t *ipv6_addr,
  790. uint16_t ipv6_orport,
  791. uint16_t ipv6_dirport,
  792. firewall_connection_t fw_connection,
  793. int pref_only,
  794. int pref_ipv6,
  795. tor_addr_port_t* ap)
  796. {
  797. tor_addr_t ipv4_addr;
  798. tor_addr_from_ipv4h(&ipv4_addr, ipv4h_addr);
  799. return fascist_firewall_choose_address_base(&ipv4_addr, ipv4_orport,
  800. ipv4_dirport, ipv6_addr,
  801. ipv6_orport, ipv6_dirport,
  802. fw_connection, pref_only,
  803. pref_ipv6, ap);
  804. }
  805. /** Like fascist_firewall_choose_address_base(), but takes <b>rs</b>.
  806. * Consults the corresponding node, then falls back to rs if node is NULL.
  807. * This should only happen when there's no valid consensus, and rs doesn't
  808. * correspond to a bridge client's bridge.
  809. */
  810. int
  811. fascist_firewall_choose_address_rs(const routerstatus_t *rs,
  812. firewall_connection_t fw_connection,
  813. int pref_only, tor_addr_port_t* ap)
  814. {
  815. if (!rs) {
  816. return 0;
  817. }
  818. tor_assert(ap);
  819. const node_t *node = node_get_by_id(rs->identity_digest);
  820. if (node) {
  821. return fascist_firewall_choose_address_node(node, fw_connection, pref_only,
  822. ap);
  823. } else {
  824. /* There's no node-specific IPv6 preference, so use the generic IPv6
  825. * preference instead. */
  826. const or_options_t *options = get_options();
  827. int pref_ipv6 = (fw_connection == FIREWALL_OR_CONNECTION
  828. ? fascist_firewall_prefer_ipv6_orport(options)
  829. : fascist_firewall_prefer_ipv6_dirport(options));
  830. /* Assume IPv4 and IPv6 DirPorts are the same.
  831. * Assume the IPv6 OR and Dir addresses are the same. */
  832. return fascist_firewall_choose_address_ipv4h(rs->addr,
  833. rs->or_port,
  834. rs->dir_port,
  835. &rs->ipv6_addr,
  836. rs->ipv6_orport,
  837. rs->dir_port,
  838. fw_connection,
  839. pref_only,
  840. pref_ipv6,
  841. ap);
  842. }
  843. }
  844. /** Like fascist_firewall_choose_address_base(), but takes <b>node</b>, and
  845. * looks up the node's IPv6 preference rather than taking an argument
  846. * for pref_ipv6. */
  847. int
  848. fascist_firewall_choose_address_node(const node_t *node,
  849. firewall_connection_t fw_connection,
  850. int pref_only, tor_addr_port_t *ap)
  851. {
  852. if (!node) {
  853. return 0;
  854. }
  855. node_assert_ok(node);
  856. const int pref_ipv6_node = (fw_connection == FIREWALL_OR_CONNECTION
  857. ? node_ipv6_or_preferred(node)
  858. : node_ipv6_dir_preferred(node));
  859. tor_addr_port_t ipv4_or_ap;
  860. node_get_prim_orport(node, &ipv4_or_ap);
  861. tor_addr_port_t ipv4_dir_ap;
  862. node_get_prim_dirport(node, &ipv4_dir_ap);
  863. tor_addr_port_t ipv6_or_ap;
  864. node_get_pref_ipv6_orport(node, &ipv6_or_ap);
  865. tor_addr_port_t ipv6_dir_ap;
  866. node_get_pref_ipv6_dirport(node, &ipv6_dir_ap);
  867. /* Assume the IPv6 OR and Dir addresses are the same. */
  868. return fascist_firewall_choose_address_base(&ipv4_or_ap.addr,
  869. ipv4_or_ap.port,
  870. ipv4_dir_ap.port,
  871. &ipv6_or_ap.addr,
  872. ipv6_or_ap.port,
  873. ipv6_dir_ap.port,
  874. fw_connection,
  875. pref_only,
  876. pref_ipv6_node,
  877. ap);
  878. }
  879. /** Like fascist_firewall_choose_address_rs(), but takes <b>ds</b>. */
  880. int
  881. fascist_firewall_choose_address_dir_server(const dir_server_t *ds,
  882. firewall_connection_t fw_connection,
  883. int pref_only,
  884. tor_addr_port_t *ap)
  885. {
  886. if (!ds) {
  887. return 0;
  888. }
  889. /* A dir_server_t always has a fake_status. As long as it has the same
  890. * addresses/ports in both fake_status and dir_server_t, this works fine.
  891. * (See #17867.)
  892. * This function relies on fascist_firewall_choose_address_rs looking up the
  893. * node if it can, because that will get the latest info for the relay. */
  894. return fascist_firewall_choose_address_rs(&ds->fake_status, fw_connection,
  895. pref_only, ap);
  896. }
  897. /** Return 1 if <b>addr</b> is permitted to connect to our dir port,
  898. * based on <b>dir_policy</b>. Else return 0.
  899. */
  900. int
  901. dir_policy_permits_address(const tor_addr_t *addr)
  902. {
  903. return addr_policy_permits_tor_addr(addr, 1, dir_policy);
  904. }
  905. /** Return 1 if <b>addr</b> is permitted to connect to our socks port,
  906. * based on <b>socks_policy</b>. Else return 0.
  907. */
  908. int
  909. socks_policy_permits_address(const tor_addr_t *addr)
  910. {
  911. return addr_policy_permits_tor_addr(addr, 1, socks_policy);
  912. }
  913. /** Return true iff the address <b>addr</b> is in a country listed in the
  914. * case-insensitive list of country codes <b>cc_list</b>. */
  915. static int
  916. addr_is_in_cc_list(uint32_t addr, const smartlist_t *cc_list)
  917. {
  918. country_t country;
  919. const char *name;
  920. tor_addr_t tar;
  921. if (!cc_list)
  922. return 0;
  923. /* XXXXipv6 */
  924. tor_addr_from_ipv4h(&tar, addr);
  925. country = geoip_get_country_by_addr(&tar);
  926. name = geoip_get_country_name(country);
  927. return smartlist_contains_string_case(cc_list, name);
  928. }
  929. /** Return 1 if <b>addr</b>:<b>port</b> is permitted to publish to our
  930. * directory, based on <b>authdir_reject_policy</b>. Else return 0.
  931. */
  932. int
  933. authdir_policy_permits_address(uint32_t addr, uint16_t port)
  934. {
  935. if (! addr_policy_permits_address(addr, port, authdir_reject_policy))
  936. return 0;
  937. return !addr_is_in_cc_list(addr, get_options()->AuthDirRejectCCs);
  938. }
  939. /** Return 1 if <b>addr</b>:<b>port</b> is considered valid in our
  940. * directory, based on <b>authdir_invalid_policy</b>. Else return 0.
  941. */
  942. int
  943. authdir_policy_valid_address(uint32_t addr, uint16_t port)
  944. {
  945. if (! addr_policy_permits_address(addr, port, authdir_invalid_policy))
  946. return 0;
  947. return !addr_is_in_cc_list(addr, get_options()->AuthDirInvalidCCs);
  948. }
  949. /** Return 1 if <b>addr</b>:<b>port</b> should be marked as a bad exit,
  950. * based on <b>authdir_badexit_policy</b>. Else return 0.
  951. */
  952. int
  953. authdir_policy_badexit_address(uint32_t addr, uint16_t port)
  954. {
  955. if (! addr_policy_permits_address(addr, port, authdir_badexit_policy))
  956. return 1;
  957. return addr_is_in_cc_list(addr, get_options()->AuthDirBadExitCCs);
  958. }
  959. #define REJECT(arg) \
  960. STMT_BEGIN *msg = tor_strdup(arg); goto err; STMT_END
  961. /** Config helper: If there's any problem with the policy configuration
  962. * options in <b>options</b>, return -1 and set <b>msg</b> to a newly
  963. * allocated description of the error. Else return 0. */
  964. int
  965. validate_addr_policies(const or_options_t *options, char **msg)
  966. {
  967. /* XXXX Maybe merge this into parse_policies_from_options, to make sure
  968. * that the two can't go out of sync. */
  969. smartlist_t *addr_policy=NULL;
  970. *msg = NULL;
  971. if (policies_parse_exit_policy_from_options(options,0,NULL,&addr_policy)) {
  972. REJECT("Error in ExitPolicy entry.");
  973. }
  974. static int warned_about_exitrelay = 0;
  975. const int exitrelay_setting_is_auto = options->ExitRelay == -1;
  976. const int policy_accepts_something =
  977. ! (policy_is_reject_star(addr_policy, AF_INET) &&
  978. policy_is_reject_star(addr_policy, AF_INET6));
  979. if (server_mode(options) &&
  980. ! warned_about_exitrelay &&
  981. exitrelay_setting_is_auto &&
  982. policy_accepts_something) {
  983. /* Policy accepts something */
  984. warned_about_exitrelay = 1;
  985. log_warn(LD_CONFIG,
  986. "Tor is running as an exit relay%s. If you did not want this "
  987. "behavior, please set the ExitRelay option to 0. If you do "
  988. "want to run an exit Relay, please set the ExitRelay option "
  989. "to 1 to disable this warning, and for forward compatibility.",
  990. options->ExitPolicy == NULL ?
  991. " with the default exit policy" : "");
  992. if (options->ExitPolicy == NULL) {
  993. log_warn(LD_CONFIG,
  994. "In a future version of Tor, ExitRelay 0 may become the "
  995. "default when no ExitPolicy is given.");
  996. }
  997. }
  998. /* The rest of these calls *append* to addr_policy. So don't actually
  999. * use the results for anything other than checking if they parse! */
  1000. if (parse_addr_policy(options->DirPolicy, &addr_policy, -1))
  1001. REJECT("Error in DirPolicy entry.");
  1002. if (parse_addr_policy(options->SocksPolicy, &addr_policy, -1))
  1003. REJECT("Error in SocksPolicy entry.");
  1004. if (parse_addr_policy(options->AuthDirReject, &addr_policy,
  1005. ADDR_POLICY_REJECT))
  1006. REJECT("Error in AuthDirReject entry.");
  1007. if (parse_addr_policy(options->AuthDirInvalid, &addr_policy,
  1008. ADDR_POLICY_REJECT))
  1009. REJECT("Error in AuthDirInvalid entry.");
  1010. if (parse_addr_policy(options->AuthDirBadExit, &addr_policy,
  1011. ADDR_POLICY_REJECT))
  1012. REJECT("Error in AuthDirBadExit entry.");
  1013. if (parse_addr_policy(options->ReachableAddresses, &addr_policy,
  1014. ADDR_POLICY_ACCEPT))
  1015. REJECT("Error in ReachableAddresses entry.");
  1016. if (parse_addr_policy(options->ReachableORAddresses, &addr_policy,
  1017. ADDR_POLICY_ACCEPT))
  1018. REJECT("Error in ReachableORAddresses entry.");
  1019. if (parse_addr_policy(options->ReachableDirAddresses, &addr_policy,
  1020. ADDR_POLICY_ACCEPT))
  1021. REJECT("Error in ReachableDirAddresses entry.");
  1022. err:
  1023. addr_policy_list_free(addr_policy);
  1024. return *msg ? -1 : 0;
  1025. #undef REJECT
  1026. }
  1027. /** Parse <b>string</b> in the same way that the exit policy
  1028. * is parsed, and put the processed version in *<b>policy</b>.
  1029. * Ignore port specifiers.
  1030. */
  1031. static int
  1032. load_policy_from_option(config_line_t *config, const char *option_name,
  1033. smartlist_t **policy,
  1034. int assume_action)
  1035. {
  1036. int r;
  1037. int killed_any_ports = 0;
  1038. addr_policy_list_free(*policy);
  1039. *policy = NULL;
  1040. r = parse_addr_policy(config, policy, assume_action);
  1041. if (r < 0) {
  1042. return -1;
  1043. }
  1044. if (*policy) {
  1045. SMARTLIST_FOREACH_BEGIN(*policy, addr_policy_t *, n) {
  1046. /* ports aren't used in these. */
  1047. if (n->prt_min > 1 || n->prt_max != 65535) {
  1048. addr_policy_t newp, *c;
  1049. memcpy(&newp, n, sizeof(newp));
  1050. newp.prt_min = 1;
  1051. newp.prt_max = 65535;
  1052. newp.is_canonical = 0;
  1053. c = addr_policy_get_canonical_entry(&newp);
  1054. SMARTLIST_REPLACE_CURRENT(*policy, n, c);
  1055. addr_policy_free(n);
  1056. killed_any_ports = 1;
  1057. }
  1058. } SMARTLIST_FOREACH_END(n);
  1059. }
  1060. if (killed_any_ports) {
  1061. log_warn(LD_CONFIG, "Ignoring ports in %s option.", option_name);
  1062. }
  1063. return 0;
  1064. }
  1065. /** Set all policies based on <b>options</b>, which should have been validated
  1066. * first by validate_addr_policies. */
  1067. int
  1068. policies_parse_from_options(const or_options_t *options)
  1069. {
  1070. int ret = 0;
  1071. if (load_policy_from_option(options->SocksPolicy, "SocksPolicy",
  1072. &socks_policy, -1) < 0)
  1073. ret = -1;
  1074. if (load_policy_from_option(options->DirPolicy, "DirPolicy",
  1075. &dir_policy, -1) < 0)
  1076. ret = -1;
  1077. if (load_policy_from_option(options->AuthDirReject, "AuthDirReject",
  1078. &authdir_reject_policy, ADDR_POLICY_REJECT) < 0)
  1079. ret = -1;
  1080. if (load_policy_from_option(options->AuthDirInvalid, "AuthDirInvalid",
  1081. &authdir_invalid_policy, ADDR_POLICY_REJECT) < 0)
  1082. ret = -1;
  1083. if (load_policy_from_option(options->AuthDirBadExit, "AuthDirBadExit",
  1084. &authdir_badexit_policy, ADDR_POLICY_REJECT) < 0)
  1085. ret = -1;
  1086. if (parse_reachable_addresses() < 0)
  1087. ret = -1;
  1088. return ret;
  1089. }
  1090. /** Compare two provided address policy items, and return -1, 0, or 1
  1091. * if the first is less than, equal to, or greater than the second. */
  1092. static int
  1093. cmp_single_addr_policy(addr_policy_t *a, addr_policy_t *b)
  1094. {
  1095. int r;
  1096. if ((r=((int)a->policy_type - (int)b->policy_type)))
  1097. return r;
  1098. if ((r=((int)a->is_private - (int)b->is_private)))
  1099. return r;
  1100. /* refcnt and is_canonical are irrelevant to equality,
  1101. * they are hash table implementation details */
  1102. if ((r=tor_addr_compare(&a->addr, &b->addr, CMP_EXACT)))
  1103. return r;
  1104. if ((r=((int)a->maskbits - (int)b->maskbits)))
  1105. return r;
  1106. if ((r=((int)a->prt_min - (int)b->prt_min)))
  1107. return r;
  1108. if ((r=((int)a->prt_max - (int)b->prt_max)))
  1109. return r;
  1110. return 0;
  1111. }
  1112. /** Like cmp_single_addr_policy() above, but looks at the
  1113. * whole set of policies in each case. */
  1114. int
  1115. cmp_addr_policies(smartlist_t *a, smartlist_t *b)
  1116. {
  1117. int r, i;
  1118. int len_a = a ? smartlist_len(a) : 0;
  1119. int len_b = b ? smartlist_len(b) : 0;
  1120. for (i = 0; i < len_a && i < len_b; ++i) {
  1121. if ((r = cmp_single_addr_policy(smartlist_get(a, i), smartlist_get(b, i))))
  1122. return r;
  1123. }
  1124. if (i == len_a && i == len_b)
  1125. return 0;
  1126. if (i < len_a)
  1127. return -1;
  1128. else
  1129. return 1;
  1130. }
  1131. /** Node in hashtable used to store address policy entries. */
  1132. typedef struct policy_map_ent_t {
  1133. HT_ENTRY(policy_map_ent_t) node;
  1134. addr_policy_t *policy;
  1135. } policy_map_ent_t;
  1136. /* DOCDOC policy_root */
  1137. static HT_HEAD(policy_map, policy_map_ent_t) policy_root = HT_INITIALIZER();
  1138. /** Return true iff a and b are equal. */
  1139. static inline int
  1140. policy_eq(policy_map_ent_t *a, policy_map_ent_t *b)
  1141. {
  1142. return cmp_single_addr_policy(a->policy, b->policy) == 0;
  1143. }
  1144. /** Return a hashcode for <b>ent</b> */
  1145. static unsigned int
  1146. policy_hash(const policy_map_ent_t *ent)
  1147. {
  1148. const addr_policy_t *a = ent->policy;
  1149. addr_policy_t aa;
  1150. memset(&aa, 0, sizeof(aa));
  1151. aa.prt_min = a->prt_min;
  1152. aa.prt_max = a->prt_max;
  1153. aa.maskbits = a->maskbits;
  1154. aa.policy_type = a->policy_type;
  1155. aa.is_private = a->is_private;
  1156. if (a->is_private) {
  1157. aa.is_private = 1;
  1158. } else {
  1159. tor_addr_copy_tight(&aa.addr, &a->addr);
  1160. }
  1161. return (unsigned) siphash24g(&aa, sizeof(aa));
  1162. }
  1163. HT_PROTOTYPE(policy_map, policy_map_ent_t, node, policy_hash,
  1164. policy_eq)
  1165. HT_GENERATE2(policy_map, policy_map_ent_t, node, policy_hash,
  1166. policy_eq, 0.6, tor_reallocarray_, tor_free_)
  1167. /** Given a pointer to an addr_policy_t, return a copy of the pointer to the
  1168. * "canonical" copy of that addr_policy_t; the canonical copy is a single
  1169. * reference-counted object. */
  1170. addr_policy_t *
  1171. addr_policy_get_canonical_entry(addr_policy_t *e)
  1172. {
  1173. policy_map_ent_t search, *found;
  1174. if (e->is_canonical)
  1175. return e;
  1176. search.policy = e;
  1177. found = HT_FIND(policy_map, &policy_root, &search);
  1178. if (!found) {
  1179. found = tor_malloc_zero(sizeof(policy_map_ent_t));
  1180. found->policy = tor_memdup(e, sizeof(addr_policy_t));
  1181. found->policy->is_canonical = 1;
  1182. found->policy->refcnt = 0;
  1183. HT_INSERT(policy_map, &policy_root, found);
  1184. }
  1185. tor_assert(!cmp_single_addr_policy(found->policy, e));
  1186. ++found->policy->refcnt;
  1187. return found->policy;
  1188. }
  1189. /** Helper for compare_tor_addr_to_addr_policy. Implements the case where
  1190. * addr and port are both known. */
  1191. static addr_policy_result_t
  1192. compare_known_tor_addr_to_addr_policy(const tor_addr_t *addr, uint16_t port,
  1193. const smartlist_t *policy)
  1194. {
  1195. /* We know the address and port, and we know the policy, so we can just
  1196. * compute an exact match. */
  1197. SMARTLIST_FOREACH_BEGIN(policy, addr_policy_t *, tmpe) {
  1198. if (tmpe->addr.family == AF_UNSPEC) {
  1199. log_warn(LD_BUG, "Policy contains an AF_UNSPEC address, which only "
  1200. "matches other AF_UNSPEC addresses.");
  1201. }
  1202. /* Address is known */
  1203. if (!tor_addr_compare_masked(addr, &tmpe->addr, tmpe->maskbits,
  1204. CMP_EXACT)) {
  1205. if (port >= tmpe->prt_min && port <= tmpe->prt_max) {
  1206. /* Exact match for the policy */
  1207. return tmpe->policy_type == ADDR_POLICY_ACCEPT ?
  1208. ADDR_POLICY_ACCEPTED : ADDR_POLICY_REJECTED;
  1209. }
  1210. }
  1211. } SMARTLIST_FOREACH_END(tmpe);
  1212. /* accept all by default. */
  1213. return ADDR_POLICY_ACCEPTED;
  1214. }
  1215. /** Helper for compare_tor_addr_to_addr_policy. Implements the case where
  1216. * addr is known but port is not. */
  1217. static addr_policy_result_t
  1218. compare_known_tor_addr_to_addr_policy_noport(const tor_addr_t *addr,
  1219. const smartlist_t *policy)
  1220. {
  1221. /* We look to see if there's a definite match. If so, we return that
  1222. match's value, unless there's an intervening possible match that says
  1223. something different. */
  1224. int maybe_accept = 0, maybe_reject = 0;
  1225. SMARTLIST_FOREACH_BEGIN(policy, addr_policy_t *, tmpe) {
  1226. if (tmpe->addr.family == AF_UNSPEC) {
  1227. log_warn(LD_BUG, "Policy contains an AF_UNSPEC address, which only "
  1228. "matches other AF_UNSPEC addresses.");
  1229. }
  1230. if (!tor_addr_compare_masked(addr, &tmpe->addr, tmpe->maskbits,
  1231. CMP_EXACT)) {
  1232. if (tmpe->prt_min <= 1 && tmpe->prt_max >= 65535) {
  1233. /* Definitely matches, since it covers all ports. */
  1234. if (tmpe->policy_type == ADDR_POLICY_ACCEPT) {
  1235. /* If we already hit a clause that might trigger a 'reject', than we
  1236. * can't be sure of this certain 'accept'.*/
  1237. return maybe_reject ? ADDR_POLICY_PROBABLY_ACCEPTED :
  1238. ADDR_POLICY_ACCEPTED;
  1239. } else {
  1240. return maybe_accept ? ADDR_POLICY_PROBABLY_REJECTED :
  1241. ADDR_POLICY_REJECTED;
  1242. }
  1243. } else {
  1244. /* Might match. */
  1245. if (tmpe->policy_type == ADDR_POLICY_REJECT)
  1246. maybe_reject = 1;
  1247. else
  1248. maybe_accept = 1;
  1249. }
  1250. }
  1251. } SMARTLIST_FOREACH_END(tmpe);
  1252. /* accept all by default. */
  1253. return maybe_reject ? ADDR_POLICY_PROBABLY_ACCEPTED : ADDR_POLICY_ACCEPTED;
  1254. }
  1255. /** Helper for compare_tor_addr_to_addr_policy. Implements the case where
  1256. * port is known but address is not. */
  1257. static addr_policy_result_t
  1258. compare_unknown_tor_addr_to_addr_policy(uint16_t port,
  1259. const smartlist_t *policy)
  1260. {
  1261. /* We look to see if there's a definite match. If so, we return that
  1262. match's value, unless there's an intervening possible match that says
  1263. something different. */
  1264. int maybe_accept = 0, maybe_reject = 0;
  1265. SMARTLIST_FOREACH_BEGIN(policy, addr_policy_t *, tmpe) {
  1266. if (tmpe->addr.family == AF_UNSPEC) {
  1267. log_warn(LD_BUG, "Policy contains an AF_UNSPEC address, which only "
  1268. "matches other AF_UNSPEC addresses.");
  1269. }
  1270. if (tmpe->prt_min <= port && port <= tmpe->prt_max) {
  1271. if (tmpe->maskbits == 0) {
  1272. /* Definitely matches, since it covers all addresses. */
  1273. if (tmpe->policy_type == ADDR_POLICY_ACCEPT) {
  1274. /* If we already hit a clause that might trigger a 'reject', than we
  1275. * can't be sure of this certain 'accept'.*/
  1276. return maybe_reject ? ADDR_POLICY_PROBABLY_ACCEPTED :
  1277. ADDR_POLICY_ACCEPTED;
  1278. } else {
  1279. return maybe_accept ? ADDR_POLICY_PROBABLY_REJECTED :
  1280. ADDR_POLICY_REJECTED;
  1281. }
  1282. } else {
  1283. /* Might match. */
  1284. if (tmpe->policy_type == ADDR_POLICY_REJECT)
  1285. maybe_reject = 1;
  1286. else
  1287. maybe_accept = 1;
  1288. }
  1289. }
  1290. } SMARTLIST_FOREACH_END(tmpe);
  1291. /* accept all by default. */
  1292. return maybe_reject ? ADDR_POLICY_PROBABLY_ACCEPTED : ADDR_POLICY_ACCEPTED;
  1293. }
  1294. /** Decide whether a given addr:port is definitely accepted,
  1295. * definitely rejected, probably accepted, or probably rejected by a
  1296. * given policy. If <b>addr</b> is 0, we don't know the IP of the
  1297. * target address. If <b>port</b> is 0, we don't know the port of the
  1298. * target address. (At least one of <b>addr</b> and <b>port</b> must be
  1299. * provided. If you want to know whether a policy would definitely reject
  1300. * an unknown address:port, use policy_is_reject_star().)
  1301. *
  1302. * We could do better by assuming that some ranges never match typical
  1303. * addresses (127.0.0.1, and so on). But we'll try this for now.
  1304. */
  1305. MOCK_IMPL(addr_policy_result_t,
  1306. compare_tor_addr_to_addr_policy,(const tor_addr_t *addr, uint16_t port,
  1307. const smartlist_t *policy))
  1308. {
  1309. if (!policy) {
  1310. /* no policy? accept all. */
  1311. return ADDR_POLICY_ACCEPTED;
  1312. } else if (addr == NULL || tor_addr_is_null(addr)) {
  1313. if (port == 0) {
  1314. log_info(LD_BUG, "Rejecting null address with 0 port (family %d)",
  1315. addr ? tor_addr_family(addr) : -1);
  1316. return ADDR_POLICY_REJECTED;
  1317. }
  1318. return compare_unknown_tor_addr_to_addr_policy(port, policy);
  1319. } else if (port == 0) {
  1320. return compare_known_tor_addr_to_addr_policy_noport(addr, policy);
  1321. } else {
  1322. return compare_known_tor_addr_to_addr_policy(addr, port, policy);
  1323. }
  1324. }
  1325. /** Return true iff the address policy <b>a</b> covers every case that
  1326. * would be covered by <b>b</b>, so that a,b is redundant. */
  1327. static int
  1328. addr_policy_covers(addr_policy_t *a, addr_policy_t *b)
  1329. {
  1330. if (tor_addr_family(&a->addr) != tor_addr_family(&b->addr)) {
  1331. /* You can't cover a different family. */
  1332. return 0;
  1333. }
  1334. /* We can ignore accept/reject, since "accept *:80, reject *:80" reduces
  1335. * to "accept *:80". */
  1336. if (a->maskbits > b->maskbits) {
  1337. /* a has more fixed bits than b; it can't possibly cover b. */
  1338. return 0;
  1339. }
  1340. if (tor_addr_compare_masked(&a->addr, &b->addr, a->maskbits, CMP_EXACT)) {
  1341. /* There's a fixed bit in a that's set differently in b. */
  1342. return 0;
  1343. }
  1344. return (a->prt_min <= b->prt_min && a->prt_max >= b->prt_max);
  1345. }
  1346. /** Return true iff the address policies <b>a</b> and <b>b</b> intersect,
  1347. * that is, there exists an address/port that is covered by <b>a</b> that
  1348. * is also covered by <b>b</b>.
  1349. */
  1350. static int
  1351. addr_policy_intersects(addr_policy_t *a, addr_policy_t *b)
  1352. {
  1353. maskbits_t minbits;
  1354. /* All the bits we care about are those that are set in both
  1355. * netmasks. If they are equal in a and b's networkaddresses
  1356. * then the networks intersect. If there is a difference,
  1357. * then they do not. */
  1358. if (a->maskbits < b->maskbits)
  1359. minbits = a->maskbits;
  1360. else
  1361. minbits = b->maskbits;
  1362. if (tor_addr_compare_masked(&a->addr, &b->addr, minbits, CMP_EXACT))
  1363. return 0;
  1364. if (a->prt_max < b->prt_min || b->prt_max < a->prt_min)
  1365. return 0;
  1366. return 1;
  1367. }
  1368. /** Add the exit policy described by <b>more</b> to <b>policy</b>.
  1369. */
  1370. STATIC void
  1371. append_exit_policy_string(smartlist_t **policy, const char *more)
  1372. {
  1373. config_line_t tmp;
  1374. tmp.key = NULL;
  1375. tmp.value = (char*) more;
  1376. tmp.next = NULL;
  1377. if (parse_addr_policy(&tmp, policy, -1)<0) {
  1378. log_warn(LD_BUG, "Unable to parse internally generated policy %s",more);
  1379. }
  1380. }
  1381. /** Add "reject <b>addr</b>:*" to <b>dest</b>, creating the list as needed. */
  1382. void
  1383. addr_policy_append_reject_addr(smartlist_t **dest, const tor_addr_t *addr)
  1384. {
  1385. tor_assert(dest);
  1386. tor_assert(addr);
  1387. addr_policy_t p, *add;
  1388. memset(&p, 0, sizeof(p));
  1389. p.policy_type = ADDR_POLICY_REJECT;
  1390. p.maskbits = tor_addr_family(addr) == AF_INET6 ? 128 : 32;
  1391. tor_addr_copy(&p.addr, addr);
  1392. p.prt_min = 1;
  1393. p.prt_max = 65535;
  1394. add = addr_policy_get_canonical_entry(&p);
  1395. if (!*dest)
  1396. *dest = smartlist_new();
  1397. smartlist_add(*dest, add);
  1398. log_debug(LD_CONFIG, "Adding a reject ExitPolicy 'reject %s:*'",
  1399. fmt_addr(addr));
  1400. }
  1401. /* Is addr public for the purposes of rejection? */
  1402. static int
  1403. tor_addr_is_public_for_reject(const tor_addr_t *addr)
  1404. {
  1405. return (!tor_addr_is_null(addr) && !tor_addr_is_internal(addr, 0)
  1406. && !tor_addr_is_multicast(addr));
  1407. }
  1408. /* Add "reject <b>addr</b>:*" to <b>dest</b>, creating the list as needed.
  1409. * Filter the address, only adding an IPv4 reject rule if ipv4_rules
  1410. * is true, and similarly for ipv6_rules. Check each address returns true for
  1411. * tor_addr_is_public_for_reject before adding it.
  1412. */
  1413. static void
  1414. addr_policy_append_reject_addr_filter(smartlist_t **dest,
  1415. const tor_addr_t *addr,
  1416. int ipv4_rules,
  1417. int ipv6_rules)
  1418. {
  1419. tor_assert(dest);
  1420. tor_assert(addr);
  1421. /* Only reject IP addresses which are public */
  1422. if (tor_addr_is_public_for_reject(addr)) {
  1423. /* Reject IPv4 addresses and IPv6 addresses based on the filters */
  1424. int is_ipv4 = tor_addr_is_v4(addr);
  1425. if ((is_ipv4 && ipv4_rules) || (!is_ipv4 && ipv6_rules)) {
  1426. addr_policy_append_reject_addr(dest, addr);
  1427. }
  1428. }
  1429. }
  1430. /** Add "reject addr:*" to <b>dest</b>, for each addr in addrs, creating the
  1431. * list as needed. */
  1432. void
  1433. addr_policy_append_reject_addr_list(smartlist_t **dest,
  1434. const smartlist_t *addrs)
  1435. {
  1436. tor_assert(dest);
  1437. tor_assert(addrs);
  1438. SMARTLIST_FOREACH_BEGIN(addrs, tor_addr_t *, addr) {
  1439. addr_policy_append_reject_addr(dest, addr);
  1440. } SMARTLIST_FOREACH_END(addr);
  1441. }
  1442. /** Add "reject addr:*" to <b>dest</b>, for each addr in addrs, creating the
  1443. * list as needed. Filter using */
  1444. static void
  1445. addr_policy_append_reject_addr_list_filter(smartlist_t **dest,
  1446. const smartlist_t *addrs,
  1447. int ipv4_rules,
  1448. int ipv6_rules)
  1449. {
  1450. tor_assert(dest);
  1451. tor_assert(addrs);
  1452. SMARTLIST_FOREACH_BEGIN(addrs, tor_addr_t *, addr) {
  1453. addr_policy_append_reject_addr_filter(dest, addr, ipv4_rules, ipv6_rules);
  1454. } SMARTLIST_FOREACH_END(addr);
  1455. }
  1456. /** Detect and excise "dead code" from the policy *<b>dest</b>. */
  1457. static void
  1458. exit_policy_remove_redundancies(smartlist_t *dest)
  1459. {
  1460. addr_policy_t *ap, *tmp;
  1461. int i, j;
  1462. /* Step one: kill every ipv4 thing after *4:*, every IPv6 thing after *6:*
  1463. */
  1464. {
  1465. int kill_v4=0, kill_v6=0;
  1466. for (i = 0; i < smartlist_len(dest); ++i) {
  1467. sa_family_t family;
  1468. ap = smartlist_get(dest, i);
  1469. family = tor_addr_family(&ap->addr);
  1470. if ((family == AF_INET && kill_v4) ||
  1471. (family == AF_INET6 && kill_v6)) {
  1472. smartlist_del_keeporder(dest, i--);
  1473. addr_policy_free(ap);
  1474. continue;
  1475. }
  1476. if (ap->maskbits == 0 && ap->prt_min <= 1 && ap->prt_max >= 65535) {
  1477. /* This is a catch-all line -- later lines are unreachable. */
  1478. if (family == AF_INET) {
  1479. kill_v4 = 1;
  1480. } else if (family == AF_INET6) {
  1481. kill_v6 = 1;
  1482. }
  1483. }
  1484. }
  1485. }
  1486. /* Step two: for every entry, see if there's a redundant entry
  1487. * later on, and remove it. */
  1488. for (i = 0; i < smartlist_len(dest)-1; ++i) {
  1489. ap = smartlist_get(dest, i);
  1490. for (j = i+1; j < smartlist_len(dest); ++j) {
  1491. tmp = smartlist_get(dest, j);
  1492. tor_assert(j > i);
  1493. if (addr_policy_covers(ap, tmp)) {
  1494. char p1[POLICY_BUF_LEN], p2[POLICY_BUF_LEN];
  1495. policy_write_item(p1, sizeof(p1), tmp, 0);
  1496. policy_write_item(p2, sizeof(p2), ap, 0);
  1497. log_debug(LD_CONFIG, "Removing exit policy %s (%d). It is made "
  1498. "redundant by %s (%d).", p1, j, p2, i);
  1499. smartlist_del_keeporder(dest, j--);
  1500. addr_policy_free(tmp);
  1501. }
  1502. }
  1503. }
  1504. /* Step three: for every entry A, see if there's an entry B making this one
  1505. * redundant later on. This is the case if A and B are of the same type
  1506. * (accept/reject), A is a subset of B, and there is no other entry of
  1507. * different type in between those two that intersects with A.
  1508. *
  1509. * Anybody want to double-check the logic here? XXX
  1510. */
  1511. for (i = 0; i < smartlist_len(dest)-1; ++i) {
  1512. ap = smartlist_get(dest, i);
  1513. for (j = i+1; j < smartlist_len(dest); ++j) {
  1514. // tor_assert(j > i); // j starts out at i+1; j only increases; i only
  1515. // // decreases.
  1516. tmp = smartlist_get(dest, j);
  1517. if (ap->policy_type != tmp->policy_type) {
  1518. if (addr_policy_intersects(ap, tmp))
  1519. break;
  1520. } else { /* policy_types are equal. */
  1521. if (addr_policy_covers(tmp, ap)) {
  1522. char p1[POLICY_BUF_LEN], p2[POLICY_BUF_LEN];
  1523. policy_write_item(p1, sizeof(p1), ap, 0);
  1524. policy_write_item(p2, sizeof(p2), tmp, 0);
  1525. log_debug(LD_CONFIG, "Removing exit policy %s. It is already "
  1526. "covered by %s.", p1, p2);
  1527. smartlist_del_keeporder(dest, i--);
  1528. addr_policy_free(ap);
  1529. break;
  1530. }
  1531. }
  1532. }
  1533. }
  1534. }
  1535. /** Reject private helper for policies_parse_exit_policy_internal: rejects
  1536. * publicly routable addresses on this exit relay.
  1537. *
  1538. * Add reject entries to the linked list *<b>dest</b>:
  1539. * <ul>
  1540. * <li>if configured_addresses is non-NULL, add entries that reject each
  1541. * tor_addr_t in the list as a destination.
  1542. * <li>if reject_interface_addresses is true, add entries that reject each
  1543. * public IPv4 and IPv6 address of each interface on this machine.
  1544. * <li>if reject_configured_port_addresses is true, add entries that reject
  1545. * each IPv4 and IPv6 address configured for a port.
  1546. * </ul>
  1547. *
  1548. * IPv6 entries are only added if ipv6_exit is true. (All IPv6 addresses are
  1549. * already blocked by policies_parse_exit_policy_internal if ipv6_exit is
  1550. * false.)
  1551. *
  1552. * The list in <b>dest</b> is created as needed.
  1553. */
  1554. void
  1555. policies_parse_exit_policy_reject_private(
  1556. smartlist_t **dest,
  1557. int ipv6_exit,
  1558. const smartlist_t *configured_addresses,
  1559. int reject_interface_addresses,
  1560. int reject_configured_port_addresses)
  1561. {
  1562. tor_assert(dest);
  1563. /* Reject configured addresses, if they are from public netblocks. */
  1564. if (configured_addresses) {
  1565. addr_policy_append_reject_addr_list_filter(dest, configured_addresses,
  1566. 1, ipv6_exit);
  1567. }
  1568. /* Reject configured port addresses, if they are from public netblocks. */
  1569. if (reject_configured_port_addresses) {
  1570. const smartlist_t *port_addrs = get_configured_ports();
  1571. SMARTLIST_FOREACH_BEGIN(port_addrs, port_cfg_t *, port) {
  1572. /* Only reject port IP addresses, not port unix sockets */
  1573. if (!port->is_unix_addr) {
  1574. addr_policy_append_reject_addr_filter(dest, &port->addr, 1, ipv6_exit);
  1575. }
  1576. } SMARTLIST_FOREACH_END(port);
  1577. }
  1578. /* Reject local addresses from public netblocks on any interface. */
  1579. if (reject_interface_addresses) {
  1580. smartlist_t *public_addresses = NULL;
  1581. /* Reject public IPv4 addresses on any interface */
  1582. public_addresses = get_interface_address6_list(LOG_INFO, AF_INET, 0);
  1583. addr_policy_append_reject_addr_list_filter(dest, public_addresses, 1, 0);
  1584. free_interface_address6_list(public_addresses);
  1585. /* Don't look for IPv6 addresses if we're configured as IPv4-only */
  1586. if (ipv6_exit) {
  1587. /* Reject public IPv6 addresses on any interface */
  1588. public_addresses = get_interface_address6_list(LOG_INFO, AF_INET6, 0);
  1589. addr_policy_append_reject_addr_list_filter(dest, public_addresses, 0, 1);
  1590. free_interface_address6_list(public_addresses);
  1591. }
  1592. }
  1593. /* If addresses were added multiple times, remove all but one of them. */
  1594. if (*dest) {
  1595. exit_policy_remove_redundancies(*dest);
  1596. }
  1597. }
  1598. /**
  1599. * Iterate through <b>policy</b> looking for redundant entries. Log a
  1600. * warning message with the first redundant entry, if any is found.
  1601. */
  1602. static void
  1603. policies_log_first_redundant_entry(const smartlist_t *policy)
  1604. {
  1605. int found_final_effective_entry = 0;
  1606. int first_redundant_entry = 0;
  1607. tor_assert(policy);
  1608. SMARTLIST_FOREACH_BEGIN(policy, const addr_policy_t *, p) {
  1609. sa_family_t family;
  1610. int found_ipv4_wildcard = 0, found_ipv6_wildcard = 0;
  1611. const int i = p_sl_idx;
  1612. /* Look for accept/reject *[4|6|]:* entires */
  1613. if (p->prt_min <= 1 && p->prt_max == 65535 && p->maskbits == 0) {
  1614. family = tor_addr_family(&p->addr);
  1615. /* accept/reject *:* may have already been expanded into
  1616. * accept/reject *4:*,accept/reject *6:*
  1617. * But handle both forms.
  1618. */
  1619. if (family == AF_INET || family == AF_UNSPEC) {
  1620. found_ipv4_wildcard = 1;
  1621. }
  1622. if (family == AF_INET6 || family == AF_UNSPEC) {
  1623. found_ipv6_wildcard = 1;
  1624. }
  1625. }
  1626. /* We also find accept *4:*,reject *6:* ; and
  1627. * accept *4:*,<other policies>,accept *6:* ; and similar.
  1628. * That's ok, because they make any subsequent entries redundant. */
  1629. if (found_ipv4_wildcard && found_ipv6_wildcard) {
  1630. found_final_effective_entry = 1;
  1631. /* if we're not on the final entry in the list */
  1632. if (i < smartlist_len(policy) - 1) {
  1633. first_redundant_entry = i + 1;
  1634. }
  1635. break;
  1636. }
  1637. } SMARTLIST_FOREACH_END(p);
  1638. /* Work out if there are redundant trailing entries in the policy list */
  1639. if (found_final_effective_entry && first_redundant_entry > 0) {
  1640. const addr_policy_t *p;
  1641. /* Longest possible policy is
  1642. * "accept6 ffff:ffff:..255/128:10000-65535",
  1643. * which contains a max-length IPv6 address, plus 24 characters. */
  1644. char line[TOR_ADDR_BUF_LEN + 32];
  1645. tor_assert(first_redundant_entry < smartlist_len(policy));
  1646. p = smartlist_get(policy, first_redundant_entry);
  1647. /* since we've already parsed the policy into an addr_policy_t struct,
  1648. * we might not log exactly what the user typed in */
  1649. policy_write_item(line, TOR_ADDR_BUF_LEN + 32, p, 0);
  1650. log_warn(LD_DIR, "Exit policy '%s' and all following policies are "
  1651. "redundant, as it follows accept/reject *:* rules for both "
  1652. "IPv4 and IPv6. They will be removed from the exit policy. (Use "
  1653. "accept/reject *:* as the last entry in any exit policy.)",
  1654. line);
  1655. }
  1656. }
  1657. #define DEFAULT_EXIT_POLICY \
  1658. "reject *:25,reject *:119,reject *:135-139,reject *:445," \
  1659. "reject *:563,reject *:1214,reject *:4661-4666," \
  1660. "reject *:6346-6429,reject *:6699,reject *:6881-6999,accept *:*"
  1661. /** Parse the exit policy <b>cfg</b> into the linked list *<b>dest</b>.
  1662. *
  1663. * If <b>ipv6_exit</b> is false, prepend "reject *6:*" to the policy.
  1664. *
  1665. * If <b>configured_addresses</b> contains addresses:
  1666. * - prepend entries that reject the addresses in this list. These may be the
  1667. * advertised relay addresses and/or the outbound bind addresses,
  1668. * depending on the ExitPolicyRejectPrivate and
  1669. * ExitPolicyRejectLocalInterfaces settings.
  1670. * If <b>rejectprivate</b> is true:
  1671. * - prepend "reject private:*" to the policy.
  1672. * If <b>reject_interface_addresses</b> is true:
  1673. * - prepend entries that reject publicly routable interface addresses on
  1674. * this exit relay by calling policies_parse_exit_policy_reject_private
  1675. * If <b>reject_configured_port_addresses</b> is true:
  1676. * - prepend entries that reject all configured port addresses
  1677. *
  1678. * If cfg doesn't end in an absolute accept or reject and if
  1679. * <b>add_default_policy</b> is true, add the default exit
  1680. * policy afterwards.
  1681. *
  1682. * Return -1 if we can't parse cfg, else return 0.
  1683. *
  1684. * This function is used to parse the exit policy from our torrc. For
  1685. * the functions used to parse the exit policy from a router descriptor,
  1686. * see router_add_exit_policy.
  1687. */
  1688. static int
  1689. policies_parse_exit_policy_internal(config_line_t *cfg,
  1690. smartlist_t **dest,
  1691. int ipv6_exit,
  1692. int rejectprivate,
  1693. const smartlist_t *configured_addresses,
  1694. int reject_interface_addresses,
  1695. int reject_configured_port_addresses,
  1696. int add_default_policy)
  1697. {
  1698. if (!ipv6_exit) {
  1699. append_exit_policy_string(dest, "reject *6:*");
  1700. }
  1701. if (rejectprivate) {
  1702. /* Reject IPv4 and IPv6 reserved private netblocks */
  1703. append_exit_policy_string(dest, "reject private:*");
  1704. }
  1705. /* Consider rejecting IPv4 and IPv6 advertised relay addresses, outbound bind
  1706. * addresses, publicly routable addresses, and configured port addresses
  1707. * on this exit relay */
  1708. policies_parse_exit_policy_reject_private(dest, ipv6_exit,
  1709. configured_addresses,
  1710. reject_interface_addresses,
  1711. reject_configured_port_addresses);
  1712. if (parse_addr_policy(cfg, dest, -1))
  1713. return -1;
  1714. /* Before we add the default policy and final rejects, check to see if
  1715. * there are any lines after accept *:* or reject *:*. These lines have no
  1716. * effect, and are most likely an error. */
  1717. policies_log_first_redundant_entry(*dest);
  1718. if (add_default_policy) {
  1719. append_exit_policy_string(dest, DEFAULT_EXIT_POLICY);
  1720. } else {
  1721. append_exit_policy_string(dest, "reject *4:*");
  1722. append_exit_policy_string(dest, "reject *6:*");
  1723. }
  1724. exit_policy_remove_redundancies(*dest);
  1725. return 0;
  1726. }
  1727. /** Parse exit policy in <b>cfg</b> into <b>dest</b> smartlist.
  1728. *
  1729. * Prepend an entry that rejects all IPv6 destinations unless
  1730. * <b>EXIT_POLICY_IPV6_ENABLED</b> bit is set in <b>options</b> bitmask.
  1731. *
  1732. * If <b>EXIT_POLICY_REJECT_PRIVATE</b> bit is set in <b>options</b>:
  1733. * - prepend an entry that rejects all destinations in all netblocks
  1734. * reserved for private use.
  1735. * - prepend entries that reject the advertised relay addresses in
  1736. * configured_addresses
  1737. * If <b>EXIT_POLICY_REJECT_LOCAL_INTERFACES</b> bit is set in <b>options</b>:
  1738. * - prepend entries that reject publicly routable addresses on this exit
  1739. * relay by calling policies_parse_exit_policy_internal
  1740. * - prepend entries that reject the outbound bind addresses in
  1741. * configured_addresses
  1742. * - prepend entries that reject all configured port addresses
  1743. *
  1744. * If <b>EXIT_POLICY_ADD_DEFAULT</b> bit is set in <b>options</b>, append
  1745. * default exit policy entries to <b>result</b> smartlist.
  1746. */
  1747. int
  1748. policies_parse_exit_policy(config_line_t *cfg, smartlist_t **dest,
  1749. exit_policy_parser_cfg_t options,
  1750. const smartlist_t *configured_addresses)
  1751. {
  1752. int ipv6_enabled = (options & EXIT_POLICY_IPV6_ENABLED) ? 1 : 0;
  1753. int reject_private = (options & EXIT_POLICY_REJECT_PRIVATE) ? 1 : 0;
  1754. int add_default = (options & EXIT_POLICY_ADD_DEFAULT) ? 1 : 0;
  1755. int reject_local_interfaces = (options &
  1756. EXIT_POLICY_REJECT_LOCAL_INTERFACES) ? 1 : 0;
  1757. return policies_parse_exit_policy_internal(cfg,dest,ipv6_enabled,
  1758. reject_private,
  1759. configured_addresses,
  1760. reject_local_interfaces,
  1761. reject_local_interfaces,
  1762. add_default);
  1763. }
  1764. /** Helper function that adds a copy of addr to a smartlist as long as it is
  1765. * non-NULL and not tor_addr_is_null().
  1766. *
  1767. * The caller is responsible for freeing all the tor_addr_t* in the smartlist.
  1768. */
  1769. static void
  1770. policies_copy_addr_to_smartlist(smartlist_t *addr_list, const tor_addr_t *addr)
  1771. {
  1772. if (addr && !tor_addr_is_null(addr)) {
  1773. tor_addr_t *addr_copy = tor_malloc(sizeof(tor_addr_t));
  1774. tor_addr_copy(addr_copy, addr);
  1775. smartlist_add(addr_list, addr_copy);
  1776. }
  1777. }
  1778. /** Helper function that adds ipv4h_addr to a smartlist as a tor_addr_t *,
  1779. * as long as it is not tor_addr_is_null(), by converting it to a tor_addr_t
  1780. * and passing it to policies_add_addr_to_smartlist.
  1781. *
  1782. * The caller is responsible for freeing all the tor_addr_t* in the smartlist.
  1783. */
  1784. static void
  1785. policies_copy_ipv4h_to_smartlist(smartlist_t *addr_list, uint32_t ipv4h_addr)
  1786. {
  1787. if (ipv4h_addr) {
  1788. tor_addr_t ipv4_tor_addr;
  1789. tor_addr_from_ipv4h(&ipv4_tor_addr, ipv4h_addr);
  1790. policies_copy_addr_to_smartlist(addr_list, &ipv4_tor_addr);
  1791. }
  1792. }
  1793. /** Helper function that adds copies of
  1794. * or_options->OutboundBindAddressIPv[4|6]_ to a smartlist as tor_addr_t *, as
  1795. * long as or_options is non-NULL, and the addresses are not
  1796. * tor_addr_is_null(), by passing them to policies_add_addr_to_smartlist.
  1797. *
  1798. * The caller is responsible for freeing all the tor_addr_t* in the smartlist.
  1799. */
  1800. static void
  1801. policies_copy_outbound_addresses_to_smartlist(smartlist_t *addr_list,
  1802. const or_options_t *or_options)
  1803. {
  1804. if (or_options) {
  1805. policies_copy_addr_to_smartlist(addr_list,
  1806. &or_options->OutboundBindAddressIPv4_);
  1807. policies_copy_addr_to_smartlist(addr_list,
  1808. &or_options->OutboundBindAddressIPv6_);
  1809. }
  1810. }
  1811. /** Parse <b>ExitPolicy</b> member of <b>or_options</b> into <b>result</b>
  1812. * smartlist.
  1813. * If <b>or_options->IPv6Exit</b> is false, prepend an entry that
  1814. * rejects all IPv6 destinations.
  1815. *
  1816. * If <b>or_options->ExitPolicyRejectPrivate</b> is true:
  1817. * - prepend an entry that rejects all destinations in all netblocks reserved
  1818. * for private use.
  1819. * - if local_address is non-zero, treat it as a host-order IPv4 address, and
  1820. * add it to the list of configured addresses.
  1821. * - if ipv6_local_address is non-NULL, and not the null tor_addr_t, add it
  1822. * to the list of configured addresses.
  1823. * If <b>or_options->ExitPolicyRejectLocalInterfaces</b> is true:
  1824. * - if or_options->OutboundBindAddressIPv4_ is not the null tor_addr_t, add
  1825. * it to the list of configured addresses.
  1826. * - if or_options->OutboundBindAddressIPv6_ is not the null tor_addr_t, add
  1827. * it to the list of configured addresses.
  1828. *
  1829. * If <b>or_options->BridgeRelay</b> is false, append entries of default
  1830. * Tor exit policy into <b>result</b> smartlist.
  1831. *
  1832. * If or_options->ExitRelay is false, then make our exit policy into
  1833. * "reject *:*" regardless.
  1834. */
  1835. int
  1836. policies_parse_exit_policy_from_options(const or_options_t *or_options,
  1837. uint32_t local_address,
  1838. const tor_addr_t *ipv6_local_address,
  1839. smartlist_t **result)
  1840. {
  1841. exit_policy_parser_cfg_t parser_cfg = 0;
  1842. smartlist_t *configured_addresses = NULL;
  1843. int rv = 0;
  1844. /* Short-circuit for non-exit relays */
  1845. if (or_options->ExitRelay == 0) {
  1846. append_exit_policy_string(result, "reject *4:*");
  1847. append_exit_policy_string(result, "reject *6:*");
  1848. return 0;
  1849. }
  1850. configured_addresses = smartlist_new();
  1851. /* Configure the parser */
  1852. if (or_options->IPv6Exit) {
  1853. parser_cfg |= EXIT_POLICY_IPV6_ENABLED;
  1854. }
  1855. if (or_options->ExitPolicyRejectPrivate) {
  1856. parser_cfg |= EXIT_POLICY_REJECT_PRIVATE;
  1857. }
  1858. if (!or_options->BridgeRelay) {
  1859. parser_cfg |= EXIT_POLICY_ADD_DEFAULT;
  1860. }
  1861. if (or_options->ExitPolicyRejectLocalInterfaces) {
  1862. parser_cfg |= EXIT_POLICY_REJECT_LOCAL_INTERFACES;
  1863. }
  1864. /* Copy the configured addresses into the tor_addr_t* list */
  1865. if (or_options->ExitPolicyRejectPrivate) {
  1866. policies_copy_ipv4h_to_smartlist(configured_addresses, local_address);
  1867. policies_copy_addr_to_smartlist(configured_addresses, ipv6_local_address);
  1868. }
  1869. if (or_options->ExitPolicyRejectLocalInterfaces) {
  1870. policies_copy_outbound_addresses_to_smartlist(configured_addresses,
  1871. or_options);
  1872. }
  1873. rv = policies_parse_exit_policy(or_options->ExitPolicy, result, parser_cfg,
  1874. configured_addresses);
  1875. SMARTLIST_FOREACH(configured_addresses, tor_addr_t *, a, tor_free(a));
  1876. smartlist_free(configured_addresses);
  1877. return rv;
  1878. }
  1879. /** Add "reject *:*" to the end of the policy in *<b>dest</b>, allocating
  1880. * *<b>dest</b> as needed. */
  1881. void
  1882. policies_exit_policy_append_reject_star(smartlist_t **dest)
  1883. {
  1884. append_exit_policy_string(dest, "reject *4:*");
  1885. append_exit_policy_string(dest, "reject *6:*");
  1886. }
  1887. /** Replace the exit policy of <b>node</b> with reject *:* */
  1888. void
  1889. policies_set_node_exitpolicy_to_reject_all(node_t *node)
  1890. {
  1891. node->rejects_all = 1;
  1892. }
  1893. /** Return 1 if there is at least one /8 subnet in <b>policy</b> that
  1894. * allows exiting to <b>port</b>. Otherwise, return 0. */
  1895. static int
  1896. exit_policy_is_general_exit_helper(smartlist_t *policy, int port)
  1897. {
  1898. uint32_t mask, ip, i;
  1899. /* Is this /8 rejected (1), or undecided (0)? */
  1900. char subnet_status[256];
  1901. memset(subnet_status, 0, sizeof(subnet_status));
  1902. SMARTLIST_FOREACH_BEGIN(policy, addr_policy_t *, p) {
  1903. if (tor_addr_family(&p->addr) != AF_INET)
  1904. continue; /* IPv4 only for now */
  1905. if (p->prt_min > port || p->prt_max < port)
  1906. continue; /* Doesn't cover our port. */
  1907. mask = 0;
  1908. tor_assert(p->maskbits <= 32);
  1909. if (p->maskbits)
  1910. mask = UINT32_MAX<<(32-p->maskbits);
  1911. ip = tor_addr_to_ipv4h(&p->addr);
  1912. /* Calculate the first and last subnet that this exit policy touches
  1913. * and set it as loop boundaries. */
  1914. for (i = ((mask & ip)>>24); i <= (~((mask & ip) ^ mask)>>24); ++i) {
  1915. tor_addr_t addr;
  1916. if (subnet_status[i] != 0)
  1917. continue; /* We already reject some part of this /8 */
  1918. tor_addr_from_ipv4h(&addr, i<<24);
  1919. if (tor_addr_is_internal(&addr, 0) &&
  1920. !get_options()->DirAllowPrivateAddresses) {
  1921. continue; /* Local or non-routable addresses */
  1922. }
  1923. if (p->policy_type == ADDR_POLICY_ACCEPT) {
  1924. if (p->maskbits > 8)
  1925. continue; /* Narrower than a /8. */
  1926. /* We found an allowed subnet of at least size /8. Done
  1927. * for this port! */
  1928. return 1;
  1929. } else if (p->policy_type == ADDR_POLICY_REJECT) {
  1930. subnet_status[i] = 1;
  1931. }
  1932. }
  1933. } SMARTLIST_FOREACH_END(p);
  1934. return 0;
  1935. }
  1936. /** Return true iff <b>ri</b> is "useful as an exit node", meaning
  1937. * it allows exit to at least one /8 address space for at least
  1938. * two of ports 80, 443, and 6667. */
  1939. int
  1940. exit_policy_is_general_exit(smartlist_t *policy)
  1941. {
  1942. static const int ports[] = { 80, 443, 6667 };
  1943. int n_allowed = 0;
  1944. int i;
  1945. if (!policy) /*XXXX disallow NULL policies? */
  1946. return 0;
  1947. for (i = 0; i < 3; ++i) {
  1948. n_allowed += exit_policy_is_general_exit_helper(policy, ports[i]);
  1949. }
  1950. return n_allowed >= 2;
  1951. }
  1952. /** Return false if <b>policy</b> might permit access to some addr:port;
  1953. * otherwise if we are certain it rejects everything, return true. */
  1954. int
  1955. policy_is_reject_star(const smartlist_t *policy, sa_family_t family)
  1956. {
  1957. if (!policy) /*XXXX disallow NULL policies? */
  1958. return 1;
  1959. SMARTLIST_FOREACH_BEGIN(policy, addr_policy_t *, p) {
  1960. if (p->policy_type == ADDR_POLICY_ACCEPT &&
  1961. (tor_addr_family(&p->addr) == family ||
  1962. tor_addr_family(&p->addr) == AF_UNSPEC)) {
  1963. return 0;
  1964. } else if (p->policy_type == ADDR_POLICY_REJECT &&
  1965. p->prt_min <= 1 && p->prt_max == 65535 &&
  1966. p->maskbits == 0 &&
  1967. (tor_addr_family(&p->addr) == family ||
  1968. tor_addr_family(&p->addr) == AF_UNSPEC)) {
  1969. return 1;
  1970. }
  1971. } SMARTLIST_FOREACH_END(p);
  1972. return 1;
  1973. }
  1974. /** Write a single address policy to the buf_len byte buffer at buf. Return
  1975. * the number of characters written, or -1 on failure. */
  1976. int
  1977. policy_write_item(char *buf, size_t buflen, const addr_policy_t *policy,
  1978. int format_for_desc)
  1979. {
  1980. size_t written = 0;
  1981. char addrbuf[TOR_ADDR_BUF_LEN];
  1982. const char *addrpart;
  1983. int result;
  1984. const int is_accept = policy->policy_type == ADDR_POLICY_ACCEPT;
  1985. const sa_family_t family = tor_addr_family(&policy->addr);
  1986. const int is_ip6 = (family == AF_INET6);
  1987. tor_addr_to_str(addrbuf, &policy->addr, sizeof(addrbuf), 1);
  1988. /* write accept/reject 1.2.3.4 */
  1989. if (policy->is_private) {
  1990. addrpart = "private";
  1991. } else if (policy->maskbits == 0) {
  1992. if (format_for_desc)
  1993. addrpart = "*";
  1994. else if (family == AF_INET6)
  1995. addrpart = "*6";
  1996. else if (family == AF_INET)
  1997. addrpart = "*4";
  1998. else
  1999. addrpart = "*";
  2000. } else {
  2001. addrpart = addrbuf;
  2002. }
  2003. result = tor_snprintf(buf, buflen, "%s%s %s",
  2004. is_accept ? "accept" : "reject",
  2005. (is_ip6&&format_for_desc)?"6":"",
  2006. addrpart);
  2007. if (result < 0)
  2008. return -1;
  2009. written += strlen(buf);
  2010. /* If the maskbits is 32 (IPv4) or 128 (IPv6) we don't need to give it. If
  2011. the mask is 0, we already wrote "*". */
  2012. if (policy->maskbits < (is_ip6?128:32) && policy->maskbits > 0) {
  2013. if (tor_snprintf(buf+written, buflen-written, "/%d", policy->maskbits)<0)
  2014. return -1;
  2015. written += strlen(buf+written);
  2016. }
  2017. if (policy->prt_min <= 1 && policy->prt_max == 65535) {
  2018. /* There is no port set; write ":*" */
  2019. if (written+4 > buflen)
  2020. return -1;
  2021. strlcat(buf+written, ":*", buflen-written);
  2022. written += 2;
  2023. } else if (policy->prt_min == policy->prt_max) {
  2024. /* There is only one port; write ":80". */
  2025. result = tor_snprintf(buf+written, buflen-written, ":%d", policy->prt_min);
  2026. if (result<0)
  2027. return -1;
  2028. written += result;
  2029. } else {
  2030. /* There is a range of ports; write ":79-80". */
  2031. result = tor_snprintf(buf+written, buflen-written, ":%d-%d",
  2032. policy->prt_min, policy->prt_max);
  2033. if (result<0)
  2034. return -1;
  2035. written += result;
  2036. }
  2037. if (written < buflen)
  2038. buf[written] = '\0';
  2039. else
  2040. return -1;
  2041. return (int)written;
  2042. }
  2043. /** Create a new exit policy summary, initially only with a single
  2044. * port 1-64k item */
  2045. /* XXXX This entire thing will do most stuff in O(N^2), or worse. Use an
  2046. * RB-tree if that turns out to matter. */
  2047. static smartlist_t *
  2048. policy_summary_create(void)
  2049. {
  2050. smartlist_t *summary;
  2051. policy_summary_item_t* item;
  2052. item = tor_malloc_zero(sizeof(policy_summary_item_t));
  2053. item->prt_min = 1;
  2054. item->prt_max = 65535;
  2055. item->reject_count = 0;
  2056. item->accepted = 0;
  2057. summary = smartlist_new();
  2058. smartlist_add(summary, item);
  2059. return summary;
  2060. }
  2061. /** Split the summary item in <b>item</b> at the port <b>new_starts</b>.
  2062. * The current item is changed to end at new-starts - 1, the new item
  2063. * copies reject_count and accepted from the old item,
  2064. * starts at new_starts and ends at the port where the original item
  2065. * previously ended.
  2066. */
  2067. static policy_summary_item_t*
  2068. policy_summary_item_split(policy_summary_item_t* old, uint16_t new_starts)
  2069. {
  2070. policy_summary_item_t* new;
  2071. new = tor_malloc_zero(sizeof(policy_summary_item_t));
  2072. new->prt_min = new_starts;
  2073. new->prt_max = old->prt_max;
  2074. new->reject_count = old->reject_count;
  2075. new->accepted = old->accepted;
  2076. old->prt_max = new_starts-1;
  2077. tor_assert(old->prt_min <= old->prt_max);
  2078. tor_assert(new->prt_min <= new->prt_max);
  2079. return new;
  2080. }
  2081. /* XXXX Nick says I'm going to hell for this. If he feels charitably towards
  2082. * my immortal soul, he can clean it up himself. */
  2083. #define AT(x) ((policy_summary_item_t*)smartlist_get(summary, x))
  2084. #define REJECT_CUTOFF_COUNT (1<<25)
  2085. /** Split an exit policy summary so that prt_min and prt_max
  2086. * fall at exactly the start and end of an item respectively.
  2087. */
  2088. static int
  2089. policy_summary_split(smartlist_t *summary,
  2090. uint16_t prt_min, uint16_t prt_max)
  2091. {
  2092. int start_at_index;
  2093. int i = 0;
  2094. while (AT(i)->prt_max < prt_min)
  2095. i++;
  2096. if (AT(i)->prt_min != prt_min) {
  2097. policy_summary_item_t* new_item;
  2098. new_item = policy_summary_item_split(AT(i), prt_min);
  2099. smartlist_insert(summary, i+1, new_item);
  2100. i++;
  2101. }
  2102. start_at_index = i;
  2103. while (AT(i)->prt_max < prt_max)
  2104. i++;
  2105. if (AT(i)->prt_max != prt_max) {
  2106. policy_summary_item_t* new_item;
  2107. new_item = policy_summary_item_split(AT(i), prt_max+1);
  2108. smartlist_insert(summary, i+1, new_item);
  2109. }
  2110. return start_at_index;
  2111. }
  2112. /** Mark port ranges as accepted if they are below the reject_count */
  2113. static void
  2114. policy_summary_accept(smartlist_t *summary,
  2115. uint16_t prt_min, uint16_t prt_max)
  2116. {
  2117. int i = policy_summary_split(summary, prt_min, prt_max);
  2118. while (i < smartlist_len(summary) &&
  2119. AT(i)->prt_max <= prt_max) {
  2120. if (!AT(i)->accepted &&
  2121. AT(i)->reject_count <= REJECT_CUTOFF_COUNT)
  2122. AT(i)->accepted = 1;
  2123. i++;
  2124. }
  2125. tor_assert(i < smartlist_len(summary) || prt_max==65535);
  2126. }
  2127. /** Count the number of addresses in a network with prefixlen maskbits
  2128. * against the given portrange. */
  2129. static void
  2130. policy_summary_reject(smartlist_t *summary,
  2131. maskbits_t maskbits,
  2132. uint16_t prt_min, uint16_t prt_max)
  2133. {
  2134. int i = policy_summary_split(summary, prt_min, prt_max);
  2135. /* XXX: ipv4 specific */
  2136. uint64_t count = (U64_LITERAL(1) << (32-maskbits));
  2137. while (i < smartlist_len(summary) &&
  2138. AT(i)->prt_max <= prt_max) {
  2139. AT(i)->reject_count += count;
  2140. i++;
  2141. }
  2142. tor_assert(i < smartlist_len(summary) || prt_max==65535);
  2143. }
  2144. /** Add a single exit policy item to our summary:
  2145. *
  2146. * If it is an accept, ignore it unless it is for all IP addresses
  2147. * ("*", i.e. its prefixlen/maskbits is 0). Otherwise call
  2148. * policy_summary_accept().
  2149. *
  2150. * If it is a reject, ignore it if it is about one of the private
  2151. * networks. Otherwise call policy_summary_reject().
  2152. */
  2153. static void
  2154. policy_summary_add_item(smartlist_t *summary, addr_policy_t *p)
  2155. {
  2156. if (p->policy_type == ADDR_POLICY_ACCEPT) {
  2157. if (p->maskbits == 0) {
  2158. policy_summary_accept(summary, p->prt_min, p->prt_max);
  2159. }
  2160. } else if (p->policy_type == ADDR_POLICY_REJECT) {
  2161. int is_private = 0;
  2162. int i;
  2163. for (i = 0; private_nets[i]; ++i) {
  2164. tor_addr_t addr;
  2165. maskbits_t maskbits;
  2166. if (tor_addr_parse_mask_ports(private_nets[i], 0, &addr,
  2167. &maskbits, NULL, NULL)<0) {
  2168. tor_assert(0);
  2169. }
  2170. if (tor_addr_compare(&p->addr, &addr, CMP_EXACT) == 0 &&
  2171. p->maskbits == maskbits) {
  2172. is_private = 1;
  2173. break;
  2174. }
  2175. }
  2176. if (!is_private) {
  2177. policy_summary_reject(summary, p->maskbits, p->prt_min, p->prt_max);
  2178. }
  2179. } else
  2180. tor_assert(0);
  2181. }
  2182. /** Create a string representing a summary for an exit policy.
  2183. * The summary will either be an "accept" plus a comma-separated list of port
  2184. * ranges or a "reject" plus port-ranges, depending on which is shorter.
  2185. *
  2186. * If no exits are allowed at all then "reject 1-65535" is returned. If no
  2187. * ports are blocked instead of "reject " we return "accept 1-65535". (These
  2188. * are an exception to the shorter-representation-wins rule).
  2189. */
  2190. char *
  2191. policy_summarize(smartlist_t *policy, sa_family_t family)
  2192. {
  2193. smartlist_t *summary = policy_summary_create();
  2194. smartlist_t *accepts, *rejects;
  2195. int i, last, start_prt;
  2196. size_t accepts_len, rejects_len;
  2197. char *accepts_str = NULL, *rejects_str = NULL, *shorter_str, *result;
  2198. const char *prefix;
  2199. tor_assert(policy);
  2200. /* Create the summary list */
  2201. SMARTLIST_FOREACH_BEGIN(policy, addr_policy_t *, p) {
  2202. sa_family_t f = tor_addr_family(&p->addr);
  2203. if (f != AF_INET && f != AF_INET6) {
  2204. log_warn(LD_BUG, "Weird family when summarizing address policy");
  2205. }
  2206. if (f != family)
  2207. continue;
  2208. /* XXXX-ipv6 More family work is needed */
  2209. policy_summary_add_item(summary, p);
  2210. } SMARTLIST_FOREACH_END(p);
  2211. /* Now create two lists of strings, one for accepted and one
  2212. * for rejected ports. We take care to merge ranges so that
  2213. * we avoid getting stuff like "1-4,5-9,10", instead we want
  2214. * "1-10"
  2215. */
  2216. i = 0;
  2217. start_prt = 1;
  2218. accepts = smartlist_new();
  2219. rejects = smartlist_new();
  2220. while (1) {
  2221. last = i == smartlist_len(summary)-1;
  2222. if (last ||
  2223. AT(i)->accepted != AT(i+1)->accepted) {
  2224. char buf[POLICY_BUF_LEN];
  2225. if (start_prt == AT(i)->prt_max)
  2226. tor_snprintf(buf, sizeof(buf), "%d", start_prt);
  2227. else
  2228. tor_snprintf(buf, sizeof(buf), "%d-%d", start_prt, AT(i)->prt_max);
  2229. if (AT(i)->accepted)
  2230. smartlist_add(accepts, tor_strdup(buf));
  2231. else
  2232. smartlist_add(rejects, tor_strdup(buf));
  2233. if (last)
  2234. break;
  2235. start_prt = AT(i+1)->prt_min;
  2236. };
  2237. i++;
  2238. };
  2239. /* Figure out which of the two stringlists will be shorter and use
  2240. * that to build the result
  2241. */
  2242. if (smartlist_len(accepts) == 0) { /* no exits at all */
  2243. result = tor_strdup("reject 1-65535");
  2244. goto cleanup;
  2245. }
  2246. if (smartlist_len(rejects) == 0) { /* no rejects at all */
  2247. result = tor_strdup("accept 1-65535");
  2248. goto cleanup;
  2249. }
  2250. accepts_str = smartlist_join_strings(accepts, ",", 0, &accepts_len);
  2251. rejects_str = smartlist_join_strings(rejects, ",", 0, &rejects_len);
  2252. if (rejects_len > MAX_EXITPOLICY_SUMMARY_LEN-strlen("reject")-1 &&
  2253. accepts_len > MAX_EXITPOLICY_SUMMARY_LEN-strlen("accept")-1) {
  2254. char *c;
  2255. shorter_str = accepts_str;
  2256. prefix = "accept";
  2257. c = shorter_str + (MAX_EXITPOLICY_SUMMARY_LEN-strlen(prefix)-1);
  2258. while (*c != ',' && c >= shorter_str)
  2259. c--;
  2260. tor_assert(c >= shorter_str);
  2261. tor_assert(*c == ',');
  2262. *c = '\0';
  2263. } else if (rejects_len < accepts_len) {
  2264. shorter_str = rejects_str;
  2265. prefix = "reject";
  2266. } else {
  2267. shorter_str = accepts_str;
  2268. prefix = "accept";
  2269. }
  2270. tor_asprintf(&result, "%s %s", prefix, shorter_str);
  2271. cleanup:
  2272. /* cleanup */
  2273. SMARTLIST_FOREACH(summary, policy_summary_item_t *, s, tor_free(s));
  2274. smartlist_free(summary);
  2275. tor_free(accepts_str);
  2276. SMARTLIST_FOREACH(accepts, char *, s, tor_free(s));
  2277. smartlist_free(accepts);
  2278. tor_free(rejects_str);
  2279. SMARTLIST_FOREACH(rejects, char *, s, tor_free(s));
  2280. smartlist_free(rejects);
  2281. return result;
  2282. }
  2283. /** Convert a summarized policy string into a short_policy_t. Return NULL
  2284. * if the string is not well-formed. */
  2285. short_policy_t *
  2286. parse_short_policy(const char *summary)
  2287. {
  2288. const char *orig_summary = summary;
  2289. short_policy_t *result;
  2290. int is_accept;
  2291. int n_entries;
  2292. short_policy_entry_t entries[MAX_EXITPOLICY_SUMMARY_LEN]; /* overkill */
  2293. const char *next;
  2294. if (!strcmpstart(summary, "accept ")) {
  2295. is_accept = 1;
  2296. summary += strlen("accept ");
  2297. } else if (!strcmpstart(summary, "reject ")) {
  2298. is_accept = 0;
  2299. summary += strlen("reject ");
  2300. } else {
  2301. log_fn(LOG_PROTOCOL_WARN, LD_DIR, "Unrecognized policy summary keyword");
  2302. return NULL;
  2303. }
  2304. n_entries = 0;
  2305. for ( ; *summary; summary = next) {
  2306. const char *comma = strchr(summary, ',');
  2307. unsigned low, high;
  2308. char dummy;
  2309. char ent_buf[32];
  2310. size_t len;
  2311. next = comma ? comma+1 : strchr(summary, '\0');
  2312. len = comma ? (size_t)(comma - summary) : strlen(summary);
  2313. if (n_entries == MAX_EXITPOLICY_SUMMARY_LEN) {
  2314. log_fn(LOG_PROTOCOL_WARN, LD_DIR, "Impossibly long policy summary %s",
  2315. escaped(orig_summary));
  2316. return NULL;
  2317. }
  2318. if (! TOR_ISDIGIT(*summary) || len > (sizeof(ent_buf)-1)) {
  2319. /* unrecognized entry format. skip it. */
  2320. continue;
  2321. }
  2322. if (len < 1) {
  2323. /* empty; skip it. */
  2324. /* XXX This happens to be unreachable, since if len==0, then *summary is
  2325. * ',' or '\0', and the TOR_ISDIGIT test above would have failed. */
  2326. continue;
  2327. }
  2328. memcpy(ent_buf, summary, len);
  2329. ent_buf[len] = '\0';
  2330. if (tor_sscanf(ent_buf, "%u-%u%c", &low, &high, &dummy) == 2) {
  2331. if (low<1 || low>65535 || high<1 || high>65535 || low>high) {
  2332. log_fn(LOG_PROTOCOL_WARN, LD_DIR,
  2333. "Found bad entry in policy summary %s", escaped(orig_summary));
  2334. return NULL;
  2335. }
  2336. } else if (tor_sscanf(ent_buf, "%u%c", &low, &dummy) == 1) {
  2337. if (low<1 || low>65535) {
  2338. log_fn(LOG_PROTOCOL_WARN, LD_DIR,
  2339. "Found bad entry in policy summary %s", escaped(orig_summary));
  2340. return NULL;
  2341. }
  2342. high = low;
  2343. } else {
  2344. log_fn(LOG_PROTOCOL_WARN, LD_DIR,"Found bad entry in policy summary %s",
  2345. escaped(orig_summary));
  2346. return NULL;
  2347. }
  2348. entries[n_entries].min_port = low;
  2349. entries[n_entries].max_port = high;
  2350. n_entries++;
  2351. }
  2352. if (n_entries == 0) {
  2353. log_fn(LOG_PROTOCOL_WARN, LD_DIR,
  2354. "Found no port-range entries in summary %s", escaped(orig_summary));
  2355. return NULL;
  2356. }
  2357. {
  2358. size_t size = STRUCT_OFFSET(short_policy_t, entries) +
  2359. sizeof(short_policy_entry_t)*(n_entries);
  2360. result = tor_malloc_zero(size);
  2361. tor_assert( (char*)&result->entries[n_entries-1] < ((char*)result)+size);
  2362. }
  2363. result->is_accept = is_accept;
  2364. result->n_entries = n_entries;
  2365. memcpy(result->entries, entries, sizeof(short_policy_entry_t)*n_entries);
  2366. return result;
  2367. }
  2368. /** Write <b>policy</b> back out into a string. Used only for unit tests
  2369. * currently. */
  2370. char *
  2371. write_short_policy(const short_policy_t *policy)
  2372. {
  2373. int i;
  2374. char *answer;
  2375. smartlist_t *sl = smartlist_new();
  2376. smartlist_add_asprintf(sl, "%s", policy->is_accept ? "accept " : "reject ");
  2377. for (i=0; i < policy->n_entries; i++) {
  2378. const short_policy_entry_t *e = &policy->entries[i];
  2379. if (e->min_port == e->max_port) {
  2380. smartlist_add_asprintf(sl, "%d", e->min_port);
  2381. } else {
  2382. smartlist_add_asprintf(sl, "%d-%d", e->min_port, e->max_port);
  2383. }
  2384. if (i < policy->n_entries-1)
  2385. smartlist_add(sl, tor_strdup(","));
  2386. }
  2387. answer = smartlist_join_strings(sl, "", 0, NULL);
  2388. SMARTLIST_FOREACH(sl, char *, a, tor_free(a));
  2389. smartlist_free(sl);
  2390. return answer;
  2391. }
  2392. /** Release all storage held in <b>policy</b>. */
  2393. void
  2394. short_policy_free(short_policy_t *policy)
  2395. {
  2396. tor_free(policy);
  2397. }
  2398. /** See whether the <b>addr</b>:<b>port</b> address is likely to be accepted
  2399. * or rejected by the summarized policy <b>policy</b>. Return values are as
  2400. * for compare_tor_addr_to_addr_policy. Unlike the regular addr_policy
  2401. * functions, requires the <b>port</b> be specified. */
  2402. addr_policy_result_t
  2403. compare_tor_addr_to_short_policy(const tor_addr_t *addr, uint16_t port,
  2404. const short_policy_t *policy)
  2405. {
  2406. int i;
  2407. int found_match = 0;
  2408. int accept_;
  2409. tor_assert(port != 0);
  2410. if (addr && tor_addr_is_null(addr))
  2411. addr = NULL; /* Unspec means 'no address at all,' in this context. */
  2412. if (addr && get_options()->ClientRejectInternalAddresses &&
  2413. (tor_addr_is_internal(addr, 0) || tor_addr_is_loopback(addr)))
  2414. return ADDR_POLICY_REJECTED;
  2415. for (i=0; i < policy->n_entries; ++i) {
  2416. const short_policy_entry_t *e = &policy->entries[i];
  2417. if (e->min_port <= port && port <= e->max_port) {
  2418. found_match = 1;
  2419. break;
  2420. }
  2421. }
  2422. if (found_match)
  2423. accept_ = policy->is_accept;
  2424. else
  2425. accept_ = ! policy->is_accept;
  2426. /* ???? are these right? -NM */
  2427. /* We should be sure not to return ADDR_POLICY_ACCEPTED in the accept
  2428. * case here, because it would cause clients to believe that the node
  2429. * allows exit enclaving. Trying it anyway would open up a cool attack
  2430. * where the node refuses due to exitpolicy, the client reacts in
  2431. * surprise by rewriting the node's exitpolicy to reject *:*, and then
  2432. * an adversary targets users by causing them to attempt such connections
  2433. * to 98% of the exits.
  2434. *
  2435. * Once microdescriptors can handle addresses in special cases (e.g. if
  2436. * we ever solve ticket 1774), we can provide certainty here. -RD */
  2437. if (accept_)
  2438. return ADDR_POLICY_PROBABLY_ACCEPTED;
  2439. else
  2440. return ADDR_POLICY_REJECTED;
  2441. }
  2442. /** Return true iff <b>policy</b> seems reject all ports */
  2443. int
  2444. short_policy_is_reject_star(const short_policy_t *policy)
  2445. {
  2446. /* This doesn't need to be as much on the lookout as policy_is_reject_star,
  2447. * since policy summaries are from the consensus or from consensus
  2448. * microdescs.
  2449. */
  2450. tor_assert(policy);
  2451. /* Check for an exact match of "reject 1-65535". */
  2452. return (policy->is_accept == 0 && policy->n_entries == 1 &&
  2453. policy->entries[0].min_port == 1 &&
  2454. policy->entries[0].max_port == 65535);
  2455. }
  2456. /** Decide whether addr:port is probably or definitely accepted or rejected by
  2457. * <b>node</b>. See compare_tor_addr_to_addr_policy for details on addr/port
  2458. * interpretation. */
  2459. addr_policy_result_t
  2460. compare_tor_addr_to_node_policy(const tor_addr_t *addr, uint16_t port,
  2461. const node_t *node)
  2462. {
  2463. if (node->rejects_all)
  2464. return ADDR_POLICY_REJECTED;
  2465. if (addr && tor_addr_family(addr) == AF_INET6) {
  2466. const short_policy_t *p = NULL;
  2467. if (node->ri)
  2468. p = node->ri->ipv6_exit_policy;
  2469. else if (node->md)
  2470. p = node->md->ipv6_exit_policy;
  2471. if (p)
  2472. return compare_tor_addr_to_short_policy(addr, port, p);
  2473. else
  2474. return ADDR_POLICY_REJECTED;
  2475. }
  2476. if (node->ri) {
  2477. return compare_tor_addr_to_addr_policy(addr, port, node->ri->exit_policy);
  2478. } else if (node->md) {
  2479. if (node->md->exit_policy == NULL)
  2480. return ADDR_POLICY_REJECTED;
  2481. else
  2482. return compare_tor_addr_to_short_policy(addr, port,
  2483. node->md->exit_policy);
  2484. } else {
  2485. return ADDR_POLICY_PROBABLY_REJECTED;
  2486. }
  2487. }
  2488. /**
  2489. * Given <b>policy_list</b>, a list of addr_policy_t, produce a string
  2490. * representation of the list.
  2491. * If <b>include_ipv4</b> is true, include IPv4 entries.
  2492. * If <b>include_ipv6</b> is true, include IPv6 entries.
  2493. */
  2494. char *
  2495. policy_dump_to_string(const smartlist_t *policy_list,
  2496. int include_ipv4,
  2497. int include_ipv6)
  2498. {
  2499. smartlist_t *policy_string_list;
  2500. char *policy_string = NULL;
  2501. policy_string_list = smartlist_new();
  2502. SMARTLIST_FOREACH_BEGIN(policy_list, addr_policy_t *, tmpe) {
  2503. char *pbuf;
  2504. int bytes_written_to_pbuf;
  2505. if ((tor_addr_family(&tmpe->addr) == AF_INET6) && (!include_ipv6)) {
  2506. continue; /* Don't include IPv6 parts of address policy */
  2507. }
  2508. if ((tor_addr_family(&tmpe->addr) == AF_INET) && (!include_ipv4)) {
  2509. continue; /* Don't include IPv4 parts of address policy */
  2510. }
  2511. pbuf = tor_malloc(POLICY_BUF_LEN);
  2512. bytes_written_to_pbuf = policy_write_item(pbuf,POLICY_BUF_LEN, tmpe, 1);
  2513. if (bytes_written_to_pbuf < 0) {
  2514. log_warn(LD_BUG, "policy_dump_to_string ran out of room!");
  2515. tor_free(pbuf);
  2516. goto done;
  2517. }
  2518. smartlist_add(policy_string_list,pbuf);
  2519. } SMARTLIST_FOREACH_END(tmpe);
  2520. policy_string = smartlist_join_strings(policy_string_list, "\n", 0, NULL);
  2521. done:
  2522. SMARTLIST_FOREACH(policy_string_list, char *, str, tor_free(str));
  2523. smartlist_free(policy_string_list);
  2524. return policy_string;
  2525. }
  2526. /** Implementation for GETINFO control command: knows the answer for questions
  2527. * about "exit-policy/..." */
  2528. int
  2529. getinfo_helper_policies(control_connection_t *conn,
  2530. const char *question, char **answer,
  2531. const char **errmsg)
  2532. {
  2533. (void) conn;
  2534. (void) errmsg;
  2535. if (!strcmp(question, "exit-policy/default")) {
  2536. *answer = tor_strdup(DEFAULT_EXIT_POLICY);
  2537. } else if (!strcmp(question, "exit-policy/reject-private/default")) {
  2538. smartlist_t *private_policy_strings;
  2539. const char **priv = private_nets;
  2540. private_policy_strings = smartlist_new();
  2541. while (*priv != NULL) {
  2542. /* IPv6 addresses are in "[]" and contain ":",
  2543. * IPv4 addresses are not in "[]" and contain "." */
  2544. smartlist_add_asprintf(private_policy_strings, "reject %s:*", *priv);
  2545. priv++;
  2546. }
  2547. *answer = smartlist_join_strings(private_policy_strings,
  2548. ",", 0, NULL);
  2549. SMARTLIST_FOREACH(private_policy_strings, char *, str, tor_free(str));
  2550. smartlist_free(private_policy_strings);
  2551. } else if (!strcmp(question, "exit-policy/reject-private/relay")) {
  2552. const or_options_t *options = get_options();
  2553. const routerinfo_t *me = router_get_my_routerinfo();
  2554. if (!me) {
  2555. *errmsg = "router_get_my_routerinfo returned NULL";
  2556. return -1;
  2557. }
  2558. if (!options->ExitPolicyRejectPrivate &&
  2559. !options->ExitPolicyRejectLocalInterfaces) {
  2560. *answer = tor_strdup("");
  2561. return 0;
  2562. }
  2563. smartlist_t *private_policy_list = smartlist_new();
  2564. smartlist_t *configured_addresses = smartlist_new();
  2565. /* Copy the configured addresses into the tor_addr_t* list */
  2566. if (options->ExitPolicyRejectPrivate) {
  2567. policies_copy_ipv4h_to_smartlist(configured_addresses, me->addr);
  2568. policies_copy_addr_to_smartlist(configured_addresses, &me->ipv6_addr);
  2569. }
  2570. if (options->ExitPolicyRejectLocalInterfaces) {
  2571. policies_copy_outbound_addresses_to_smartlist(configured_addresses,
  2572. options);
  2573. }
  2574. policies_parse_exit_policy_reject_private(
  2575. &private_policy_list,
  2576. options->IPv6Exit,
  2577. configured_addresses,
  2578. options->ExitPolicyRejectLocalInterfaces,
  2579. options->ExitPolicyRejectLocalInterfaces);
  2580. *answer = policy_dump_to_string(private_policy_list, 1, 1);
  2581. addr_policy_list_free(private_policy_list);
  2582. SMARTLIST_FOREACH(configured_addresses, tor_addr_t *, a, tor_free(a));
  2583. smartlist_free(configured_addresses);
  2584. } else if (!strcmpstart(question, "exit-policy/")) {
  2585. const routerinfo_t *me = router_get_my_routerinfo();
  2586. int include_ipv4 = 0;
  2587. int include_ipv6 = 0;
  2588. if (!strcmp(question, "exit-policy/ipv4")) {
  2589. include_ipv4 = 1;
  2590. } else if (!strcmp(question, "exit-policy/ipv6")) {
  2591. include_ipv6 = 1;
  2592. } else if (!strcmp(question, "exit-policy/full")) {
  2593. include_ipv4 = include_ipv6 = 1;
  2594. } else {
  2595. return 0; /* No such key. */
  2596. }
  2597. if (!me) {
  2598. *errmsg = "router_get_my_routerinfo returned NULL";
  2599. return -1;
  2600. }
  2601. *answer = router_dump_exit_policy_to_string(me,include_ipv4,include_ipv6);
  2602. }
  2603. return 0;
  2604. }
  2605. /** Release all storage held by <b>p</b>. */
  2606. void
  2607. addr_policy_list_free(smartlist_t *lst)
  2608. {
  2609. if (!lst)
  2610. return;
  2611. SMARTLIST_FOREACH(lst, addr_policy_t *, policy, addr_policy_free(policy));
  2612. smartlist_free(lst);
  2613. }
  2614. /** Release all storage held by <b>p</b>. */
  2615. void
  2616. addr_policy_free(addr_policy_t *p)
  2617. {
  2618. if (!p)
  2619. return;
  2620. if (--p->refcnt <= 0) {
  2621. if (p->is_canonical) {
  2622. policy_map_ent_t search, *found;
  2623. search.policy = p;
  2624. found = HT_REMOVE(policy_map, &policy_root, &search);
  2625. if (found) {
  2626. tor_assert(p == found->policy);
  2627. tor_free(found);
  2628. }
  2629. }
  2630. tor_free(p);
  2631. }
  2632. }
  2633. /** Release all storage held by policy variables. */
  2634. void
  2635. policies_free_all(void)
  2636. {
  2637. addr_policy_list_free(reachable_or_addr_policy);
  2638. reachable_or_addr_policy = NULL;
  2639. addr_policy_list_free(reachable_dir_addr_policy);
  2640. reachable_dir_addr_policy = NULL;
  2641. addr_policy_list_free(socks_policy);
  2642. socks_policy = NULL;
  2643. addr_policy_list_free(dir_policy);
  2644. dir_policy = NULL;
  2645. addr_policy_list_free(authdir_reject_policy);
  2646. authdir_reject_policy = NULL;
  2647. addr_policy_list_free(authdir_invalid_policy);
  2648. authdir_invalid_policy = NULL;
  2649. addr_policy_list_free(authdir_badexit_policy);
  2650. authdir_badexit_policy = NULL;
  2651. if (!HT_EMPTY(&policy_root)) {
  2652. policy_map_ent_t **ent;
  2653. int n = 0;
  2654. char buf[POLICY_BUF_LEN];
  2655. log_warn(LD_MM, "Still had %d address policies cached at shutdown.",
  2656. (int)HT_SIZE(&policy_root));
  2657. /* Note the first 10 cached policies to try to figure out where they
  2658. * might be coming from. */
  2659. HT_FOREACH(ent, policy_map, &policy_root) {
  2660. if (++n > 10)
  2661. break;
  2662. if (policy_write_item(buf, sizeof(buf), (*ent)->policy, 0) >= 0)
  2663. log_warn(LD_MM," %d [%d]: %s", n, (*ent)->policy->refcnt, buf);
  2664. }
  2665. }
  2666. HT_CLEAR(policy_map, &policy_root);
  2667. }