policies.c 100 KB

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  1. /* Copyright (c) 2001-2004, Roger Dingledine.
  2. * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
  3. * Copyright (c) 2007-2015, 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(0);
  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. if (!addr || tor_addr_is_null(addr) || !port) {
  370. return 0;
  371. }
  372. if (!server_mode(options)) {
  373. if (tor_addr_family(addr) == AF_INET &&
  374. (!options->ClientUseIPv4 || (pref_only && pref_ipv6)))
  375. return 0;
  376. /* Bridges can always use IPv6 */
  377. if (tor_addr_family(addr) == AF_INET6 &&
  378. (!fascist_firewall_use_ipv6(options) || (pref_only && !pref_ipv6)))
  379. return 0;
  380. }
  381. return addr_policy_permits_tor_addr(addr, port,
  382. firewall_policy);
  383. }
  384. /** Is this client configured to use IPv6?
  385. */
  386. int
  387. fascist_firewall_use_ipv6(const or_options_t *options)
  388. {
  389. /* Clients use IPv6 if it's set, or they use bridges, or they don't use
  390. * IPv4 */
  391. return (options->ClientUseIPv6 == 1 || options->UseBridges == 1
  392. || options->ClientUseIPv4 == 0);
  393. }
  394. /** Do we prefer to connect to IPv6, ignoring ClientPreferIPv6ORPort and
  395. * ClientPreferIPv6DirPort?
  396. * If we're unsure, return -1, otherwise, return 1 for IPv6 and 0 for IPv4.
  397. */
  398. static int
  399. fascist_firewall_prefer_ipv6_impl(const or_options_t *options)
  400. {
  401. /*
  402. Cheap implementation of config options ClientUseIPv4 & ClientUseIPv6 --
  403. If we're a server or IPv6 is disabled, use IPv4.
  404. If IPv4 is disabled, use IPv6.
  405. */
  406. if (server_mode(options) || !fascist_firewall_use_ipv6(options)) {
  407. return 0;
  408. }
  409. if (!options->ClientUseIPv4) {
  410. return 1;
  411. }
  412. return -1;
  413. }
  414. /** Do we prefer to connect to IPv6 ORPorts?
  415. */
  416. int
  417. fascist_firewall_prefer_ipv6_orport(const or_options_t *options)
  418. {
  419. /* node->ipv6_preferred is set from fascist_firewall_prefer_ipv6_orport()
  420. * each time the consensus is loaded.
  421. * If our preferences change, we will only reset ipv6_preferred on the node
  422. * when the next consensus is loaded. But the consensus is realoded when the
  423. * configuration changes after a HUP. So as long as the result of this
  424. * function only depends on Tor's options, everything should work ok.
  425. */
  426. int pref_ipv6 = fascist_firewall_prefer_ipv6_impl(options);
  427. if (pref_ipv6 >= 0) {
  428. return pref_ipv6;
  429. }
  430. /* We can use both IPv4 and IPv6 - which do we prefer? */
  431. if (options->ClientPreferIPv6ORPort == 1) {
  432. return 1;
  433. }
  434. return 0;
  435. }
  436. /** Do we prefer to connect to IPv6 DirPorts?
  437. */
  438. int
  439. fascist_firewall_prefer_ipv6_dirport(const or_options_t *options)
  440. {
  441. int pref_ipv6 = fascist_firewall_prefer_ipv6_impl(options);
  442. if (pref_ipv6 >= 0) {
  443. return pref_ipv6;
  444. }
  445. /* We can use both IPv4 and IPv6 - which do we prefer? */
  446. if (options->ClientPreferIPv6DirPort == 1) {
  447. return 1;
  448. }
  449. return 0;
  450. }
  451. /** Return true iff we think our firewall will let us make a connection to
  452. * addr:port. Uses ReachableORAddresses or ReachableDirAddresses based on
  453. * fw_connection.
  454. * If pref_only, return false if addr is not in the client's preferred address
  455. * family.
  456. */
  457. int
  458. fascist_firewall_allows_address_addr(const tor_addr_t *addr, uint16_t port,
  459. firewall_connection_t fw_connection,
  460. int pref_only)
  461. {
  462. const or_options_t *options = get_options();
  463. if (fw_connection == FIREWALL_OR_CONNECTION) {
  464. return fascist_firewall_allows_address(addr, port,
  465. reachable_or_addr_policy,
  466. pref_only,
  467. fascist_firewall_prefer_ipv6_orport(options));
  468. } else if (fw_connection == FIREWALL_DIR_CONNECTION) {
  469. return fascist_firewall_allows_address(addr, port,
  470. reachable_dir_addr_policy,
  471. pref_only,
  472. fascist_firewall_prefer_ipv6_dirport(options));
  473. } else {
  474. log_warn(LD_BUG, "Bad firewall_connection_t value %d.",
  475. fw_connection);
  476. return 0;
  477. }
  478. }
  479. /** Return true iff we think our firewall will let us make a connection to
  480. * addr:port (ap). Uses ReachableORAddresses or ReachableDirAddresses based on
  481. * fw_connection.
  482. * If pref_only, return false if addr is not in the client's preferred address
  483. * family.
  484. */
  485. int
  486. fascist_firewall_allows_address_ap(const tor_addr_port_t *ap,
  487. firewall_connection_t fw_connection,
  488. int pref_only)
  489. {
  490. tor_assert(ap);
  491. return fascist_firewall_allows_address_addr(&ap->addr, ap->port,
  492. fw_connection, pref_only);
  493. }
  494. /* Return true iff we think our firewall will let us make a connection to
  495. * ipv4h_or_addr:ipv4_or_port. ipv4h_or_addr is interpreted in host order.
  496. * Uses ReachableORAddresses or ReachableDirAddresses based on
  497. * fw_connection.
  498. * If pref_only, return false if addr is not in the client's preferred address
  499. * family. */
  500. int
  501. fascist_firewall_allows_address_ipv4h(uint32_t ipv4h_or_addr,
  502. uint16_t ipv4_or_port,
  503. firewall_connection_t fw_connection,
  504. int pref_only)
  505. {
  506. tor_addr_t ipv4_or_addr;
  507. tor_addr_from_ipv4h(&ipv4_or_addr, ipv4h_or_addr);
  508. return fascist_firewall_allows_address_addr(&ipv4_or_addr, ipv4_or_port,
  509. fw_connection, pref_only);
  510. }
  511. /** Return true iff we think our firewall will let us make a connection to
  512. * ipv4h_addr/ipv6_addr. Uses ipv4_orport/ipv6_orport/ReachableORAddresses or
  513. * ipv4_dirport/ipv6_dirport/ReachableDirAddresses based on IPv4/IPv6 and
  514. * <b>fw_connection</b>.
  515. * If pref_only, return false if addr is not in the client's preferred address
  516. * family. */
  517. static int
  518. fascist_firewall_allows_base(uint32_t ipv4h_addr, uint16_t ipv4_orport,
  519. uint16_t ipv4_dirport,
  520. const tor_addr_t *ipv6_addr, uint16_t ipv6_orport,
  521. uint16_t ipv6_dirport,
  522. firewall_connection_t fw_connection,
  523. int pref_only)
  524. {
  525. if (fascist_firewall_allows_address_ipv4h(ipv4h_addr,
  526. (fw_connection == FIREWALL_OR_CONNECTION
  527. ? ipv4_orport
  528. : ipv4_dirport),
  529. fw_connection,
  530. pref_only)) {
  531. return 1;
  532. }
  533. if (fascist_firewall_allows_address_addr(ipv6_addr,
  534. (fw_connection == FIREWALL_OR_CONNECTION
  535. ? ipv6_orport
  536. : ipv6_dirport),
  537. fw_connection,
  538. pref_only)) {
  539. return 1;
  540. }
  541. return 0;
  542. }
  543. /** Like fascist_firewall_allows_ri, but doesn't consult the node. */
  544. static int
  545. fascist_firewall_allows_ri_impl(const routerinfo_t *ri,
  546. firewall_connection_t fw_connection,
  547. int pref_only)
  548. {
  549. if (!ri) {
  550. return 0;
  551. }
  552. /* Assume IPv4 and IPv6 DirPorts are the same */
  553. return fascist_firewall_allows_base(ri->addr, ri->or_port, ri->dir_port,
  554. &ri->ipv6_addr, ri->ipv6_orport,
  555. ri->dir_port, fw_connection, pref_only);
  556. }
  557. /** Like fascist_firewall_allows_rs, but doesn't consult the node. */
  558. static int
  559. fascist_firewall_allows_rs_impl(const routerstatus_t *rs,
  560. firewall_connection_t fw_connection,
  561. int pref_only)
  562. {
  563. if (!rs) {
  564. return 0;
  565. }
  566. /* Assume IPv4 and IPv6 DirPorts are the same */
  567. return fascist_firewall_allows_base(rs->addr, rs->or_port, rs->dir_port,
  568. &rs->ipv6_addr, rs->ipv6_orport,
  569. rs->dir_port, fw_connection, pref_only);
  570. }
  571. /** Return true iff we think our firewall will let us make a connection to
  572. * <b>rs</b> on either its IPv4 or IPv6 address. Uses
  573. * or_port/ipv6_orport/ReachableORAddresses or dir_port/ReachableDirAddresses
  574. * based on IPv4/IPv6 and <b>fw_connection</b>.
  575. * If pref_only, return false if addr is not in the client's preferred address
  576. * family.
  577. * Consults the corresponding node if the addresses in rs are not permitted. */
  578. int
  579. fascist_firewall_allows_rs(const routerstatus_t *rs,
  580. firewall_connection_t fw_connection, int pref_only)
  581. {
  582. if (!rs) {
  583. return 0;
  584. }
  585. /* Assume IPv4 and IPv6 DirPorts are the same */
  586. if (fascist_firewall_allows_rs_impl(rs, fw_connection, pref_only)) {
  587. return 1;
  588. } else {
  589. const node_t *node = node_get_by_id(rs->identity_digest);
  590. return fascist_firewall_allows_node(node, fw_connection, pref_only);
  591. }
  592. }
  593. /** Like fascist_firewall_allows_md, but doesn't consult the node. */
  594. static int
  595. fascist_firewall_allows_md_impl(const microdesc_t *md,
  596. firewall_connection_t fw_connection,
  597. int pref_only)
  598. {
  599. if (!md) {
  600. return 0;
  601. }
  602. /* Can't check dirport, it doesn't have one */
  603. if (fw_connection == FIREWALL_DIR_CONNECTION) {
  604. return 0;
  605. }
  606. /* Also can't check IPv4, doesn't have that either */
  607. return fascist_firewall_allows_address_addr(&md->ipv6_addr, md->ipv6_orport,
  608. fw_connection, pref_only);
  609. }
  610. /** Return true iff we think our firewall will let us make a connection to
  611. * <b>node</b>:
  612. * - if <b>preferred</b> is true, on its preferred address,
  613. * - if not, on either its IPv4 or IPv6 address.
  614. * Uses or_port/ipv6_orport/ReachableORAddresses or
  615. * dir_port/ReachableDirAddresses based on IPv4/IPv6 and <b>fw_connection</b>.
  616. * If pref_only, return false if addr is not in the client's preferred address
  617. * family. */
  618. int
  619. fascist_firewall_allows_node(const node_t *node,
  620. firewall_connection_t fw_connection,
  621. int pref_only)
  622. {
  623. if (!node) {
  624. return 0;
  625. }
  626. node_assert_ok(node);
  627. /* Sometimes, the rs is missing the IPv6 address info, and we need to go
  628. * all the way to the md */
  629. if (node->ri && fascist_firewall_allows_ri_impl(node->ri, fw_connection,
  630. pref_only)) {
  631. return 1;
  632. } else if (node->rs && fascist_firewall_allows_rs_impl(node->rs,
  633. fw_connection,
  634. pref_only)) {
  635. return 1;
  636. } else if (node->md && fascist_firewall_allows_md_impl(node->md,
  637. fw_connection,
  638. pref_only)) {
  639. return 1;
  640. } else {
  641. /* If we know nothing, assume it's unreachable, we'll never get an address
  642. * to connect to. */
  643. return 0;
  644. }
  645. }
  646. /** Return true iff we think our firewall will let us make a connection to
  647. * <b>ds</b> on either its IPv4 or IPv6 address. Uses ReachableORAddresses or
  648. * ReachableDirAddresses based on <b>fw_connection</b> (some directory
  649. * connections are tunneled over ORPorts).
  650. * If pref_only, return false if addr is not in the client's preferred address
  651. * family. */
  652. int
  653. fascist_firewall_allows_dir_server(const dir_server_t *ds,
  654. firewall_connection_t fw_connection,
  655. int pref_only)
  656. {
  657. if (!ds) {
  658. return 0;
  659. }
  660. /* A dir_server_t always has a fake_status. As long as it has the same
  661. * addresses/ports in both fake_status and dir_server_t, this works fine.
  662. * (See #17867.)
  663. * This function relies on fascist_firewall_allows_rs looking up the node on
  664. * failure, because it will get the latest info for the relay. */
  665. return fascist_firewall_allows_rs(&ds->fake_status, fw_connection,
  666. pref_only);
  667. }
  668. /** If a and b are both valid and allowed by fw_connection,
  669. * choose one based on want_a and return it.
  670. * Otherwise, return whichever is allowed.
  671. * Otherwise, return NULL.
  672. * If pref_only, only return an address if it's in the client's preferred
  673. * address family. */
  674. static const tor_addr_port_t *
  675. fascist_firewall_choose_address_impl(const tor_addr_port_t *a,
  676. const tor_addr_port_t *b,
  677. int want_a,
  678. firewall_connection_t fw_connection,
  679. int pref_only)
  680. {
  681. const tor_addr_port_t *use_a = NULL;
  682. const tor_addr_port_t *use_b = NULL;
  683. if (fascist_firewall_allows_address_ap(a, fw_connection, pref_only)) {
  684. use_a = a;
  685. }
  686. if (fascist_firewall_allows_address_ap(b, fw_connection, pref_only)) {
  687. use_b = b;
  688. }
  689. /* If both are allowed */
  690. if (use_a && use_b) {
  691. /* Choose a if we want it */
  692. return (want_a ? use_a : use_b);
  693. } else {
  694. /* Choose a if we have it */
  695. return (use_a ? use_a : use_b);
  696. }
  697. }
  698. /** If a and b are both valid and preferred by fw_connection,
  699. * choose one based on want_a and return it.
  700. * Otherwise, return whichever is preferred.
  701. * If neither are preferred, and pref_only is false:
  702. * - If a and b are both allowed by fw_connection,
  703. * choose one based on want_a and return it.
  704. * - Otherwise, return whichever is preferred.
  705. * Otherwise, return NULL. */
  706. const tor_addr_port_t *
  707. fascist_firewall_choose_address(const tor_addr_port_t *a,
  708. const tor_addr_port_t *b,
  709. int want_a,
  710. firewall_connection_t fw_connection,
  711. int pref_only)
  712. {
  713. const tor_addr_port_t *pref = fascist_firewall_choose_address_impl(
  714. a, b, want_a,
  715. fw_connection,
  716. 1);
  717. if (pref_only || pref) {
  718. /* If there is a preferred address, use it. If we can only use preferred
  719. * addresses, and neither address is preferred, pref will be NULL, and we
  720. * want to return NULL, so return it. */
  721. return pref;
  722. } else {
  723. /* If there's no preferred address, and we can return addresses that are
  724. * not preferred, use an address that's allowed */
  725. return fascist_firewall_choose_address_impl(a, b, want_a, fw_connection,
  726. 0);
  727. }
  728. }
  729. /** Copy an address and port into <b>ap</b> that we think our firewall will
  730. * let us connect to. Uses ipv4_addr/ipv6_addr and
  731. * ipv4_orport/ipv6_orport/ReachableORAddresses or
  732. * ipv4_dirport/ipv6_dirport/ReachableDirAddresses based on IPv4/IPv6 and
  733. * <b>fw_connection</b>.
  734. * If pref_only, only choose preferred addresses. In either case, choose
  735. * a preferred address before an address that's not preferred.
  736. * If neither address is chosen, return 0, else return 1. */
  737. static int
  738. fascist_firewall_choose_address_base(const tor_addr_t *ipv4_addr,
  739. uint16_t ipv4_orport,
  740. uint16_t ipv4_dirport,
  741. const tor_addr_t *ipv6_addr,
  742. uint16_t ipv6_orport,
  743. uint16_t ipv6_dirport,
  744. firewall_connection_t fw_connection,
  745. int pref_only,
  746. tor_addr_port_t* ap)
  747. {
  748. const tor_addr_port_t *result = NULL;
  749. /* This argument is ignored as long as the address pair is IPv4/IPv6,
  750. * because we always have a preference in a client.
  751. * For bridge clients, this selects the preferred address, which was
  752. * previously IPv6 (if a bridge has both), so we keep that behaviour. */
  753. const int bridge_client_prefer_ipv4 = 0;
  754. tor_assert(ipv6_addr);
  755. tor_assert(ap);
  756. tor_addr_port_t ipv4_ap;
  757. tor_addr_copy(&ipv4_ap.addr, ipv4_addr);
  758. ipv4_ap.port = (fw_connection == FIREWALL_OR_CONNECTION
  759. ? ipv4_orport
  760. : ipv4_dirport);
  761. tor_addr_port_t ipv6_ap;
  762. tor_addr_copy(&ipv6_ap.addr, ipv6_addr);
  763. ipv6_ap.port = (fw_connection == FIREWALL_OR_CONNECTION
  764. ? ipv6_orport
  765. : ipv6_dirport);
  766. result = fascist_firewall_choose_address(&ipv4_ap, &ipv6_ap,
  767. bridge_client_prefer_ipv4,
  768. fw_connection, pref_only);
  769. if (result) {
  770. tor_addr_copy(&ap->addr, &result->addr);
  771. ap->port = result->port;
  772. return 1;
  773. } else {
  774. return 0;
  775. }
  776. }
  777. /** Like fascist_firewall_choose_address_base, but takes a host-order IPv4
  778. * address as the first parameter. */
  779. static int
  780. fascist_firewall_choose_address_ipv4h(uint32_t ipv4h_addr,
  781. uint16_t ipv4_orport,
  782. uint16_t ipv4_dirport,
  783. const tor_addr_t *ipv6_addr,
  784. uint16_t ipv6_orport,
  785. uint16_t ipv6_dirport,
  786. firewall_connection_t fw_connection,
  787. int pref_only,
  788. tor_addr_port_t* ap)
  789. {
  790. tor_addr_t ipv4_addr;
  791. tor_addr_from_ipv4h(&ipv4_addr, ipv4h_addr);
  792. return fascist_firewall_choose_address_base(&ipv4_addr, ipv4_orport,
  793. ipv4_dirport, ipv6_addr,
  794. ipv6_orport, ipv6_dirport,
  795. fw_connection, pref_only, ap);
  796. }
  797. #define IPV6_OR_LOOKUP(r, identity_digest, ipv6_or_ap) \
  798. STMT_BEGIN \
  799. if (!(r)->ipv6_orport || tor_addr_is_null(&(r)->ipv6_addr)) { \
  800. const node_t *node = node_get_by_id((identity_digest)); \
  801. if (node) { \
  802. node_get_pref_ipv6_orport(node, &(ipv6_or_ap)); \
  803. } else { \
  804. tor_addr_make_null(&(ipv6_or_ap).addr, AF_INET6); \
  805. (ipv6_or_ap).port = 0; \
  806. } \
  807. } else { \
  808. tor_addr_copy(&(ipv6_or_ap).addr, &(r)->ipv6_addr); \
  809. (ipv6_or_ap).port = (r)->ipv6_orport; \
  810. } \
  811. STMT_END
  812. /** Copy an address and port from <b>rs</b> into <b>ap</b> that we think our
  813. * firewall will let us connect to. Uses ipv4h_addr/ipv6_addr and
  814. * ipv4_orport/ipv6_orport/ReachableORAddresses or
  815. * ipv4_dirport/ipv6_dirport/ReachableDirAddresses based on IPv4/IPv6 and
  816. * <b>fw_connection</b>.
  817. * If pref_only, only choose preferred addresses. In either case, choose
  818. * a preferred address before an address that's not preferred.
  819. * If neither address is chosen, return 0, else return 1.
  820. * Consults the corresponding node if the addresses in rs are not valid. */
  821. int
  822. fascist_firewall_choose_address_rs(const routerstatus_t *rs,
  823. firewall_connection_t fw_connection,
  824. int pref_only, tor_addr_port_t* ap)
  825. {
  826. if (!rs) {
  827. return 0;
  828. }
  829. tor_assert(ap);
  830. /* Don't do the lookup if the IPv6 address/port in rs is OK.
  831. * If it's OK, assume the dir_port is also OK. */
  832. tor_addr_port_t ipv6_or_ap;
  833. IPV6_OR_LOOKUP(rs, rs->identity_digest, ipv6_or_ap);
  834. /* Assume IPv4 and IPv6 DirPorts are the same.
  835. * Assume the IPv6 OR and Dir addresses are the same. */
  836. return fascist_firewall_choose_address_ipv4h(rs->addr,
  837. rs->or_port,
  838. rs->dir_port,
  839. &ipv6_or_ap.addr,
  840. ipv6_or_ap.port,
  841. rs->dir_port,
  842. fw_connection,
  843. pref_only,
  844. ap);
  845. }
  846. /** Copy an address and port from <b>node</b> into <b>ap</b> that we think our
  847. * firewall will let us connect to. Uses ipv4h_addr/ipv6_addr and
  848. * ipv4_orport/ipv6_orport/ReachableORAddresses or
  849. * ipv4_dirport/ipv6_dirport/ReachableDirAddresses based on IPv4/IPv6 and
  850. * <b>fw_connection</b>.
  851. * If pref_only, only choose preferred addresses. In either case, choose
  852. * a preferred address before an address that's not preferred.
  853. * If neither address is chosen, return 0, else return 1. */
  854. int
  855. fascist_firewall_choose_address_node(const node_t *node,
  856. firewall_connection_t fw_connection,
  857. int pref_only, tor_addr_port_t *ap)
  858. {
  859. if (!node) {
  860. return 0;
  861. }
  862. node_assert_ok(node);
  863. tor_addr_port_t ipv4_or_ap;
  864. node_get_prim_orport(node, &ipv4_or_ap);
  865. tor_addr_port_t ipv4_dir_ap;
  866. node_get_prim_dirport(node, &ipv4_dir_ap);
  867. tor_addr_port_t ipv6_or_ap;
  868. node_get_pref_ipv6_orport(node, &ipv6_or_ap);
  869. tor_addr_port_t ipv6_dir_ap;
  870. node_get_pref_ipv6_dirport(node, &ipv6_dir_ap);
  871. /* Assume the IPv6 OR and Dir addresses are the same. */
  872. return fascist_firewall_choose_address_base(&ipv4_or_ap.addr,
  873. ipv4_or_ap.port,
  874. ipv4_dir_ap.port,
  875. &ipv6_or_ap.addr,
  876. ipv6_or_ap.port,
  877. ipv6_dir_ap.port,
  878. fw_connection,
  879. pref_only,
  880. ap);
  881. }
  882. /** Copy an address and port from <b>ds</b> into <b>ap</b> that we think our
  883. * firewall will let us connect to. Uses ipv4h_addr/ipv6_addr and
  884. * ipv4_orport/ipv6_orport/ReachableORAddresses or
  885. * ipv4_dirport/ipv6_dirport/ReachableDirAddresses based on IPv4/IPv6 and
  886. * <b>fw_connection</b>.
  887. * If pref_only, only choose preferred addresses. In either case, choose
  888. * a preferred address before an address that's not preferred.
  889. * If neither address is chosen, return 0, else return 1. */
  890. int
  891. fascist_firewall_choose_address_dir_server(const dir_server_t *ds,
  892. firewall_connection_t fw_connection,
  893. int pref_only, tor_addr_port_t *ap)
  894. {
  895. if (!ds) {
  896. return 0;
  897. }
  898. /* A dir_server_t always has a fake_status. As long as it has the same
  899. * addresses/ports in both fake_status and dir_server_t, this works fine.
  900. * (See #17867.)
  901. * This function relies on fascist_firewall_choose_address_rs looking up the
  902. * addresses from the node if it can, because that will get the latest info
  903. * for the relay. */
  904. return fascist_firewall_choose_address_rs(&ds->fake_status, fw_connection,
  905. pref_only, ap);
  906. }
  907. /** Return 1 if <b>addr</b> is permitted to connect to our dir port,
  908. * based on <b>dir_policy</b>. Else return 0.
  909. */
  910. int
  911. dir_policy_permits_address(const tor_addr_t *addr)
  912. {
  913. return addr_policy_permits_tor_addr(addr, 1, dir_policy);
  914. }
  915. /** Return 1 if <b>addr</b> is permitted to connect to our socks port,
  916. * based on <b>socks_policy</b>. Else return 0.
  917. */
  918. int
  919. socks_policy_permits_address(const tor_addr_t *addr)
  920. {
  921. return addr_policy_permits_tor_addr(addr, 1, socks_policy);
  922. }
  923. /** Return true iff the address <b>addr</b> is in a country listed in the
  924. * case-insensitive list of country codes <b>cc_list</b>. */
  925. static int
  926. addr_is_in_cc_list(uint32_t addr, const smartlist_t *cc_list)
  927. {
  928. country_t country;
  929. const char *name;
  930. tor_addr_t tar;
  931. if (!cc_list)
  932. return 0;
  933. /* XXXXipv6 */
  934. tor_addr_from_ipv4h(&tar, addr);
  935. country = geoip_get_country_by_addr(&tar);
  936. name = geoip_get_country_name(country);
  937. return smartlist_contains_string_case(cc_list, name);
  938. }
  939. /** Return 1 if <b>addr</b>:<b>port</b> is permitted to publish to our
  940. * directory, based on <b>authdir_reject_policy</b>. Else return 0.
  941. */
  942. int
  943. authdir_policy_permits_address(uint32_t addr, uint16_t port)
  944. {
  945. if (! addr_policy_permits_address(addr, port, authdir_reject_policy))
  946. return 0;
  947. return !addr_is_in_cc_list(addr, get_options()->AuthDirRejectCCs);
  948. }
  949. /** Return 1 if <b>addr</b>:<b>port</b> is considered valid in our
  950. * directory, based on <b>authdir_invalid_policy</b>. Else return 0.
  951. */
  952. int
  953. authdir_policy_valid_address(uint32_t addr, uint16_t port)
  954. {
  955. if (! addr_policy_permits_address(addr, port, authdir_invalid_policy))
  956. return 0;
  957. return !addr_is_in_cc_list(addr, get_options()->AuthDirInvalidCCs);
  958. }
  959. /** Return 1 if <b>addr</b>:<b>port</b> should be marked as a bad exit,
  960. * based on <b>authdir_badexit_policy</b>. Else return 0.
  961. */
  962. int
  963. authdir_policy_badexit_address(uint32_t addr, uint16_t port)
  964. {
  965. if (! addr_policy_permits_address(addr, port, authdir_badexit_policy))
  966. return 1;
  967. return addr_is_in_cc_list(addr, get_options()->AuthDirBadExitCCs);
  968. }
  969. #define REJECT(arg) \
  970. STMT_BEGIN *msg = tor_strdup(arg); goto err; STMT_END
  971. /** Config helper: If there's any problem with the policy configuration
  972. * options in <b>options</b>, return -1 and set <b>msg</b> to a newly
  973. * allocated description of the error. Else return 0. */
  974. int
  975. validate_addr_policies(const or_options_t *options, char **msg)
  976. {
  977. /* XXXX Maybe merge this into parse_policies_from_options, to make sure
  978. * that the two can't go out of sync. */
  979. smartlist_t *addr_policy=NULL;
  980. *msg = NULL;
  981. if (policies_parse_exit_policy_from_options(options,0,NULL,&addr_policy)) {
  982. REJECT("Error in ExitPolicy entry.");
  983. }
  984. static int warned_about_exitrelay = 0;
  985. const int exitrelay_setting_is_auto = options->ExitRelay == -1;
  986. const int policy_accepts_something =
  987. ! (policy_is_reject_star(addr_policy, AF_INET) &&
  988. policy_is_reject_star(addr_policy, AF_INET6));
  989. if (server_mode(options) &&
  990. ! warned_about_exitrelay &&
  991. exitrelay_setting_is_auto &&
  992. policy_accepts_something) {
  993. /* Policy accepts something */
  994. warned_about_exitrelay = 1;
  995. log_warn(LD_CONFIG,
  996. "Tor is running as an exit relay%s. If you did not want this "
  997. "behavior, please set the ExitRelay option to 0. If you do "
  998. "want to run an exit Relay, please set the ExitRelay option "
  999. "to 1 to disable this warning, and for forward compatibility.",
  1000. options->ExitPolicy == NULL ?
  1001. " with the default exit policy" : "");
  1002. if (options->ExitPolicy == NULL) {
  1003. log_warn(LD_CONFIG,
  1004. "In a future version of Tor, ExitRelay 0 may become the "
  1005. "default when no ExitPolicy is given.");
  1006. }
  1007. }
  1008. /* The rest of these calls *append* to addr_policy. So don't actually
  1009. * use the results for anything other than checking if they parse! */
  1010. if (parse_addr_policy(options->DirPolicy, &addr_policy, -1))
  1011. REJECT("Error in DirPolicy entry.");
  1012. if (parse_addr_policy(options->SocksPolicy, &addr_policy, -1))
  1013. REJECT("Error in SocksPolicy entry.");
  1014. if (parse_addr_policy(options->AuthDirReject, &addr_policy,
  1015. ADDR_POLICY_REJECT))
  1016. REJECT("Error in AuthDirReject entry.");
  1017. if (parse_addr_policy(options->AuthDirInvalid, &addr_policy,
  1018. ADDR_POLICY_REJECT))
  1019. REJECT("Error in AuthDirInvalid entry.");
  1020. if (parse_addr_policy(options->AuthDirBadExit, &addr_policy,
  1021. ADDR_POLICY_REJECT))
  1022. REJECT("Error in AuthDirBadExit entry.");
  1023. if (parse_addr_policy(options->ReachableAddresses, &addr_policy,
  1024. ADDR_POLICY_ACCEPT))
  1025. REJECT("Error in ReachableAddresses entry.");
  1026. if (parse_addr_policy(options->ReachableORAddresses, &addr_policy,
  1027. ADDR_POLICY_ACCEPT))
  1028. REJECT("Error in ReachableORAddresses entry.");
  1029. if (parse_addr_policy(options->ReachableDirAddresses, &addr_policy,
  1030. ADDR_POLICY_ACCEPT))
  1031. REJECT("Error in ReachableDirAddresses entry.");
  1032. err:
  1033. addr_policy_list_free(addr_policy);
  1034. return *msg ? -1 : 0;
  1035. #undef REJECT
  1036. }
  1037. /** Parse <b>string</b> in the same way that the exit policy
  1038. * is parsed, and put the processed version in *<b>policy</b>.
  1039. * Ignore port specifiers.
  1040. */
  1041. static int
  1042. load_policy_from_option(config_line_t *config, const char *option_name,
  1043. smartlist_t **policy,
  1044. int assume_action)
  1045. {
  1046. int r;
  1047. int killed_any_ports = 0;
  1048. addr_policy_list_free(*policy);
  1049. *policy = NULL;
  1050. r = parse_addr_policy(config, policy, assume_action);
  1051. if (r < 0) {
  1052. return -1;
  1053. }
  1054. if (*policy) {
  1055. SMARTLIST_FOREACH_BEGIN(*policy, addr_policy_t *, n) {
  1056. /* ports aren't used in these. */
  1057. if (n->prt_min > 1 || n->prt_max != 65535) {
  1058. addr_policy_t newp, *c;
  1059. memcpy(&newp, n, sizeof(newp));
  1060. newp.prt_min = 1;
  1061. newp.prt_max = 65535;
  1062. newp.is_canonical = 0;
  1063. c = addr_policy_get_canonical_entry(&newp);
  1064. SMARTLIST_REPLACE_CURRENT(*policy, n, c);
  1065. addr_policy_free(n);
  1066. killed_any_ports = 1;
  1067. }
  1068. } SMARTLIST_FOREACH_END(n);
  1069. }
  1070. if (killed_any_ports) {
  1071. log_warn(LD_CONFIG, "Ignoring ports in %s option.", option_name);
  1072. }
  1073. return 0;
  1074. }
  1075. /** Set all policies based on <b>options</b>, which should have been validated
  1076. * first by validate_addr_policies. */
  1077. int
  1078. policies_parse_from_options(const or_options_t *options)
  1079. {
  1080. int ret = 0;
  1081. if (load_policy_from_option(options->SocksPolicy, "SocksPolicy",
  1082. &socks_policy, -1) < 0)
  1083. ret = -1;
  1084. if (load_policy_from_option(options->DirPolicy, "DirPolicy",
  1085. &dir_policy, -1) < 0)
  1086. ret = -1;
  1087. if (load_policy_from_option(options->AuthDirReject, "AuthDirReject",
  1088. &authdir_reject_policy, ADDR_POLICY_REJECT) < 0)
  1089. ret = -1;
  1090. if (load_policy_from_option(options->AuthDirInvalid, "AuthDirInvalid",
  1091. &authdir_invalid_policy, ADDR_POLICY_REJECT) < 0)
  1092. ret = -1;
  1093. if (load_policy_from_option(options->AuthDirBadExit, "AuthDirBadExit",
  1094. &authdir_badexit_policy, ADDR_POLICY_REJECT) < 0)
  1095. ret = -1;
  1096. if (parse_reachable_addresses() < 0)
  1097. ret = -1;
  1098. return ret;
  1099. }
  1100. /** Compare two provided address policy items, and return -1, 0, or 1
  1101. * if the first is less than, equal to, or greater than the second. */
  1102. static int
  1103. cmp_single_addr_policy(addr_policy_t *a, addr_policy_t *b)
  1104. {
  1105. int r;
  1106. if ((r=((int)a->policy_type - (int)b->policy_type)))
  1107. return r;
  1108. if ((r=((int)a->is_private - (int)b->is_private)))
  1109. return r;
  1110. /* refcnt and is_canonical are irrelevant to equality,
  1111. * they are hash table implementation details */
  1112. if ((r=tor_addr_compare(&a->addr, &b->addr, CMP_EXACT)))
  1113. return r;
  1114. if ((r=((int)a->maskbits - (int)b->maskbits)))
  1115. return r;
  1116. if ((r=((int)a->prt_min - (int)b->prt_min)))
  1117. return r;
  1118. if ((r=((int)a->prt_max - (int)b->prt_max)))
  1119. return r;
  1120. return 0;
  1121. }
  1122. /** Like cmp_single_addr_policy() above, but looks at the
  1123. * whole set of policies in each case. */
  1124. int
  1125. cmp_addr_policies(smartlist_t *a, smartlist_t *b)
  1126. {
  1127. int r, i;
  1128. int len_a = a ? smartlist_len(a) : 0;
  1129. int len_b = b ? smartlist_len(b) : 0;
  1130. for (i = 0; i < len_a && i < len_b; ++i) {
  1131. if ((r = cmp_single_addr_policy(smartlist_get(a, i), smartlist_get(b, i))))
  1132. return r;
  1133. }
  1134. if (i == len_a && i == len_b)
  1135. return 0;
  1136. if (i < len_a)
  1137. return -1;
  1138. else
  1139. return 1;
  1140. }
  1141. /** Node in hashtable used to store address policy entries. */
  1142. typedef struct policy_map_ent_t {
  1143. HT_ENTRY(policy_map_ent_t) node;
  1144. addr_policy_t *policy;
  1145. } policy_map_ent_t;
  1146. /* DOCDOC policy_root */
  1147. static HT_HEAD(policy_map, policy_map_ent_t) policy_root = HT_INITIALIZER();
  1148. /** Return true iff a and b are equal. */
  1149. static inline int
  1150. policy_eq(policy_map_ent_t *a, policy_map_ent_t *b)
  1151. {
  1152. return cmp_single_addr_policy(a->policy, b->policy) == 0;
  1153. }
  1154. /** Return a hashcode for <b>ent</b> */
  1155. static unsigned int
  1156. policy_hash(const policy_map_ent_t *ent)
  1157. {
  1158. const addr_policy_t *a = ent->policy;
  1159. addr_policy_t aa;
  1160. memset(&aa, 0, sizeof(aa));
  1161. aa.prt_min = a->prt_min;
  1162. aa.prt_max = a->prt_max;
  1163. aa.maskbits = a->maskbits;
  1164. aa.policy_type = a->policy_type;
  1165. aa.is_private = a->is_private;
  1166. if (a->is_private) {
  1167. aa.is_private = 1;
  1168. } else {
  1169. tor_addr_copy_tight(&aa.addr, &a->addr);
  1170. }
  1171. return (unsigned) siphash24g(&aa, sizeof(aa));
  1172. }
  1173. HT_PROTOTYPE(policy_map, policy_map_ent_t, node, policy_hash,
  1174. policy_eq)
  1175. HT_GENERATE2(policy_map, policy_map_ent_t, node, policy_hash,
  1176. policy_eq, 0.6, tor_reallocarray_, tor_free_)
  1177. /** Given a pointer to an addr_policy_t, return a copy of the pointer to the
  1178. * "canonical" copy of that addr_policy_t; the canonical copy is a single
  1179. * reference-counted object. */
  1180. addr_policy_t *
  1181. addr_policy_get_canonical_entry(addr_policy_t *e)
  1182. {
  1183. policy_map_ent_t search, *found;
  1184. if (e->is_canonical)
  1185. return e;
  1186. search.policy = e;
  1187. found = HT_FIND(policy_map, &policy_root, &search);
  1188. if (!found) {
  1189. found = tor_malloc_zero(sizeof(policy_map_ent_t));
  1190. found->policy = tor_memdup(e, sizeof(addr_policy_t));
  1191. found->policy->is_canonical = 1;
  1192. found->policy->refcnt = 0;
  1193. HT_INSERT(policy_map, &policy_root, found);
  1194. }
  1195. tor_assert(!cmp_single_addr_policy(found->policy, e));
  1196. ++found->policy->refcnt;
  1197. return found->policy;
  1198. }
  1199. /** Helper for compare_tor_addr_to_addr_policy. Implements the case where
  1200. * addr and port are both known. */
  1201. static addr_policy_result_t
  1202. compare_known_tor_addr_to_addr_policy(const tor_addr_t *addr, uint16_t port,
  1203. const smartlist_t *policy)
  1204. {
  1205. /* We know the address and port, and we know the policy, so we can just
  1206. * compute an exact match. */
  1207. SMARTLIST_FOREACH_BEGIN(policy, addr_policy_t *, tmpe) {
  1208. if (tmpe->addr.family == AF_UNSPEC) {
  1209. log_warn(LD_BUG, "Policy contains an AF_UNSPEC address, which only "
  1210. "matches other AF_UNSPEC addresses.");
  1211. }
  1212. /* Address is known */
  1213. if (!tor_addr_compare_masked(addr, &tmpe->addr, tmpe->maskbits,
  1214. CMP_EXACT)) {
  1215. if (port >= tmpe->prt_min && port <= tmpe->prt_max) {
  1216. /* Exact match for the policy */
  1217. return tmpe->policy_type == ADDR_POLICY_ACCEPT ?
  1218. ADDR_POLICY_ACCEPTED : ADDR_POLICY_REJECTED;
  1219. }
  1220. }
  1221. } SMARTLIST_FOREACH_END(tmpe);
  1222. /* accept all by default. */
  1223. return ADDR_POLICY_ACCEPTED;
  1224. }
  1225. /** Helper for compare_tor_addr_to_addr_policy. Implements the case where
  1226. * addr is known but port is not. */
  1227. static addr_policy_result_t
  1228. compare_known_tor_addr_to_addr_policy_noport(const tor_addr_t *addr,
  1229. const smartlist_t *policy)
  1230. {
  1231. /* We look to see if there's a definite match. If so, we return that
  1232. match's value, unless there's an intervening possible match that says
  1233. something different. */
  1234. int maybe_accept = 0, maybe_reject = 0;
  1235. SMARTLIST_FOREACH_BEGIN(policy, addr_policy_t *, tmpe) {
  1236. if (tmpe->addr.family == AF_UNSPEC) {
  1237. log_warn(LD_BUG, "Policy contains an AF_UNSPEC address, which only "
  1238. "matches other AF_UNSPEC addresses.");
  1239. }
  1240. if (!tor_addr_compare_masked(addr, &tmpe->addr, tmpe->maskbits,
  1241. CMP_EXACT)) {
  1242. if (tmpe->prt_min <= 1 && tmpe->prt_max >= 65535) {
  1243. /* Definitely matches, since it covers all ports. */
  1244. if (tmpe->policy_type == ADDR_POLICY_ACCEPT) {
  1245. /* If we already hit a clause that might trigger a 'reject', than we
  1246. * can't be sure of this certain 'accept'.*/
  1247. return maybe_reject ? ADDR_POLICY_PROBABLY_ACCEPTED :
  1248. ADDR_POLICY_ACCEPTED;
  1249. } else {
  1250. return maybe_accept ? ADDR_POLICY_PROBABLY_REJECTED :
  1251. ADDR_POLICY_REJECTED;
  1252. }
  1253. } else {
  1254. /* Might match. */
  1255. if (tmpe->policy_type == ADDR_POLICY_REJECT)
  1256. maybe_reject = 1;
  1257. else
  1258. maybe_accept = 1;
  1259. }
  1260. }
  1261. } SMARTLIST_FOREACH_END(tmpe);
  1262. /* accept all by default. */
  1263. return maybe_reject ? ADDR_POLICY_PROBABLY_ACCEPTED : ADDR_POLICY_ACCEPTED;
  1264. }
  1265. /** Helper for compare_tor_addr_to_addr_policy. Implements the case where
  1266. * port is known but address is not. */
  1267. static addr_policy_result_t
  1268. compare_unknown_tor_addr_to_addr_policy(uint16_t port,
  1269. const smartlist_t *policy)
  1270. {
  1271. /* We look to see if there's a definite match. If so, we return that
  1272. match's value, unless there's an intervening possible match that says
  1273. something different. */
  1274. int maybe_accept = 0, maybe_reject = 0;
  1275. SMARTLIST_FOREACH_BEGIN(policy, addr_policy_t *, tmpe) {
  1276. if (tmpe->addr.family == AF_UNSPEC) {
  1277. log_warn(LD_BUG, "Policy contains an AF_UNSPEC address, which only "
  1278. "matches other AF_UNSPEC addresses.");
  1279. }
  1280. if (tmpe->prt_min <= port && port <= tmpe->prt_max) {
  1281. if (tmpe->maskbits == 0) {
  1282. /* Definitely matches, since it covers all addresses. */
  1283. if (tmpe->policy_type == ADDR_POLICY_ACCEPT) {
  1284. /* If we already hit a clause that might trigger a 'reject', than we
  1285. * can't be sure of this certain 'accept'.*/
  1286. return maybe_reject ? ADDR_POLICY_PROBABLY_ACCEPTED :
  1287. ADDR_POLICY_ACCEPTED;
  1288. } else {
  1289. return maybe_accept ? ADDR_POLICY_PROBABLY_REJECTED :
  1290. ADDR_POLICY_REJECTED;
  1291. }
  1292. } else {
  1293. /* Might match. */
  1294. if (tmpe->policy_type == ADDR_POLICY_REJECT)
  1295. maybe_reject = 1;
  1296. else
  1297. maybe_accept = 1;
  1298. }
  1299. }
  1300. } SMARTLIST_FOREACH_END(tmpe);
  1301. /* accept all by default. */
  1302. return maybe_reject ? ADDR_POLICY_PROBABLY_ACCEPTED : ADDR_POLICY_ACCEPTED;
  1303. }
  1304. /** Decide whether a given addr:port is definitely accepted,
  1305. * definitely rejected, probably accepted, or probably rejected by a
  1306. * given policy. If <b>addr</b> is 0, we don't know the IP of the
  1307. * target address. If <b>port</b> is 0, we don't know the port of the
  1308. * target address. (At least one of <b>addr</b> and <b>port</b> must be
  1309. * provided. If you want to know whether a policy would definitely reject
  1310. * an unknown address:port, use policy_is_reject_star().)
  1311. *
  1312. * We could do better by assuming that some ranges never match typical
  1313. * addresses (127.0.0.1, and so on). But we'll try this for now.
  1314. */
  1315. MOCK_IMPL(addr_policy_result_t,
  1316. compare_tor_addr_to_addr_policy,(const tor_addr_t *addr, uint16_t port,
  1317. const smartlist_t *policy))
  1318. {
  1319. if (!policy) {
  1320. /* no policy? accept all. */
  1321. return ADDR_POLICY_ACCEPTED;
  1322. } else if (addr == NULL || tor_addr_is_null(addr)) {
  1323. if (port == 0) {
  1324. log_info(LD_BUG, "Rejecting null address with 0 port (family %d)",
  1325. addr ? tor_addr_family(addr) : -1);
  1326. return ADDR_POLICY_REJECTED;
  1327. }
  1328. return compare_unknown_tor_addr_to_addr_policy(port, policy);
  1329. } else if (port == 0) {
  1330. return compare_known_tor_addr_to_addr_policy_noport(addr, policy);
  1331. } else {
  1332. return compare_known_tor_addr_to_addr_policy(addr, port, policy);
  1333. }
  1334. }
  1335. /** Return true iff the address policy <b>a</b> covers every case that
  1336. * would be covered by <b>b</b>, so that a,b is redundant. */
  1337. static int
  1338. addr_policy_covers(addr_policy_t *a, addr_policy_t *b)
  1339. {
  1340. if (tor_addr_family(&a->addr) != tor_addr_family(&b->addr)) {
  1341. /* You can't cover a different family. */
  1342. return 0;
  1343. }
  1344. /* We can ignore accept/reject, since "accept *:80, reject *:80" reduces
  1345. * to "accept *:80". */
  1346. if (a->maskbits > b->maskbits) {
  1347. /* a has more fixed bits than b; it can't possibly cover b. */
  1348. return 0;
  1349. }
  1350. if (tor_addr_compare_masked(&a->addr, &b->addr, a->maskbits, CMP_EXACT)) {
  1351. /* There's a fixed bit in a that's set differently in b. */
  1352. return 0;
  1353. }
  1354. return (a->prt_min <= b->prt_min && a->prt_max >= b->prt_max);
  1355. }
  1356. /** Return true iff the address policies <b>a</b> and <b>b</b> intersect,
  1357. * that is, there exists an address/port that is covered by <b>a</b> that
  1358. * is also covered by <b>b</b>.
  1359. */
  1360. static int
  1361. addr_policy_intersects(addr_policy_t *a, addr_policy_t *b)
  1362. {
  1363. maskbits_t minbits;
  1364. /* All the bits we care about are those that are set in both
  1365. * netmasks. If they are equal in a and b's networkaddresses
  1366. * then the networks intersect. If there is a difference,
  1367. * then they do not. */
  1368. if (a->maskbits < b->maskbits)
  1369. minbits = a->maskbits;
  1370. else
  1371. minbits = b->maskbits;
  1372. if (tor_addr_compare_masked(&a->addr, &b->addr, minbits, CMP_EXACT))
  1373. return 0;
  1374. if (a->prt_max < b->prt_min || b->prt_max < a->prt_min)
  1375. return 0;
  1376. return 1;
  1377. }
  1378. /** Add the exit policy described by <b>more</b> to <b>policy</b>.
  1379. */
  1380. STATIC void
  1381. append_exit_policy_string(smartlist_t **policy, const char *more)
  1382. {
  1383. config_line_t tmp;
  1384. tmp.key = NULL;
  1385. tmp.value = (char*) more;
  1386. tmp.next = NULL;
  1387. if (parse_addr_policy(&tmp, policy, -1)<0) {
  1388. log_warn(LD_BUG, "Unable to parse internally generated policy %s",more);
  1389. }
  1390. }
  1391. /** Add "reject <b>addr</b>:*" to <b>dest</b>, creating the list as needed. */
  1392. void
  1393. addr_policy_append_reject_addr(smartlist_t **dest, const tor_addr_t *addr)
  1394. {
  1395. tor_assert(dest);
  1396. tor_assert(addr);
  1397. addr_policy_t p, *add;
  1398. memset(&p, 0, sizeof(p));
  1399. p.policy_type = ADDR_POLICY_REJECT;
  1400. p.maskbits = tor_addr_family(addr) == AF_INET6 ? 128 : 32;
  1401. tor_addr_copy(&p.addr, addr);
  1402. p.prt_min = 1;
  1403. p.prt_max = 65535;
  1404. add = addr_policy_get_canonical_entry(&p);
  1405. if (!*dest)
  1406. *dest = smartlist_new();
  1407. smartlist_add(*dest, add);
  1408. log_debug(LD_CONFIG, "Adding a reject ExitPolicy 'reject %s:*'",
  1409. fmt_addr(addr));
  1410. }
  1411. /* Is addr public for the purposes of rejection? */
  1412. static int
  1413. tor_addr_is_public_for_reject(const tor_addr_t *addr)
  1414. {
  1415. return (!tor_addr_is_null(addr) && !tor_addr_is_internal(addr, 0)
  1416. && !tor_addr_is_multicast(addr));
  1417. }
  1418. /* Add "reject <b>addr</b>:*" to <b>dest</b>, creating the list as needed.
  1419. * Filter the address, only adding an IPv4 reject rule if ipv4_rules
  1420. * is true, and similarly for ipv6_rules. Check each address returns true for
  1421. * tor_addr_is_public_for_reject before adding it.
  1422. */
  1423. static void
  1424. addr_policy_append_reject_addr_filter(smartlist_t **dest,
  1425. const tor_addr_t *addr,
  1426. int ipv4_rules,
  1427. int ipv6_rules)
  1428. {
  1429. tor_assert(dest);
  1430. tor_assert(addr);
  1431. /* Only reject IP addresses which are public */
  1432. if (tor_addr_is_public_for_reject(addr)) {
  1433. /* Reject IPv4 addresses and IPv6 addresses based on the filters */
  1434. int is_ipv4 = tor_addr_is_v4(addr);
  1435. if ((is_ipv4 && ipv4_rules) || (!is_ipv4 && ipv6_rules)) {
  1436. addr_policy_append_reject_addr(dest, addr);
  1437. }
  1438. }
  1439. }
  1440. /** Add "reject addr:*" to <b>dest</b>, for each addr in addrs, creating the
  1441. * list as needed. */
  1442. void
  1443. addr_policy_append_reject_addr_list(smartlist_t **dest,
  1444. const smartlist_t *addrs)
  1445. {
  1446. tor_assert(dest);
  1447. tor_assert(addrs);
  1448. SMARTLIST_FOREACH_BEGIN(addrs, tor_addr_t *, addr) {
  1449. addr_policy_append_reject_addr(dest, addr);
  1450. } SMARTLIST_FOREACH_END(addr);
  1451. }
  1452. /** Add "reject addr:*" to <b>dest</b>, for each addr in addrs, creating the
  1453. * list as needed. Filter using */
  1454. static void
  1455. addr_policy_append_reject_addr_list_filter(smartlist_t **dest,
  1456. const smartlist_t *addrs,
  1457. int ipv4_rules,
  1458. int ipv6_rules)
  1459. {
  1460. tor_assert(dest);
  1461. tor_assert(addrs);
  1462. SMARTLIST_FOREACH_BEGIN(addrs, tor_addr_t *, addr) {
  1463. addr_policy_append_reject_addr_filter(dest, addr, ipv4_rules, ipv6_rules);
  1464. } SMARTLIST_FOREACH_END(addr);
  1465. }
  1466. /** Detect and excise "dead code" from the policy *<b>dest</b>. */
  1467. static void
  1468. exit_policy_remove_redundancies(smartlist_t *dest)
  1469. {
  1470. addr_policy_t *ap, *tmp;
  1471. int i, j;
  1472. /* Step one: kill every ipv4 thing after *4:*, every IPv6 thing after *6:*
  1473. */
  1474. {
  1475. int kill_v4=0, kill_v6=0;
  1476. for (i = 0; i < smartlist_len(dest); ++i) {
  1477. sa_family_t family;
  1478. ap = smartlist_get(dest, i);
  1479. family = tor_addr_family(&ap->addr);
  1480. if ((family == AF_INET && kill_v4) ||
  1481. (family == AF_INET6 && kill_v6)) {
  1482. smartlist_del_keeporder(dest, i--);
  1483. addr_policy_free(ap);
  1484. continue;
  1485. }
  1486. if (ap->maskbits == 0 && ap->prt_min <= 1 && ap->prt_max >= 65535) {
  1487. /* This is a catch-all line -- later lines are unreachable. */
  1488. if (family == AF_INET) {
  1489. kill_v4 = 1;
  1490. } else if (family == AF_INET6) {
  1491. kill_v6 = 1;
  1492. }
  1493. }
  1494. }
  1495. }
  1496. /* Step two: for every entry, see if there's a redundant entry
  1497. * later on, and remove it. */
  1498. for (i = 0; i < smartlist_len(dest)-1; ++i) {
  1499. ap = smartlist_get(dest, i);
  1500. for (j = i+1; j < smartlist_len(dest); ++j) {
  1501. tmp = smartlist_get(dest, j);
  1502. tor_assert(j > i);
  1503. if (addr_policy_covers(ap, tmp)) {
  1504. char p1[POLICY_BUF_LEN], p2[POLICY_BUF_LEN];
  1505. policy_write_item(p1, sizeof(p1), tmp, 0);
  1506. policy_write_item(p2, sizeof(p2), ap, 0);
  1507. log_debug(LD_CONFIG, "Removing exit policy %s (%d). It is made "
  1508. "redundant by %s (%d).", p1, j, p2, i);
  1509. smartlist_del_keeporder(dest, j--);
  1510. addr_policy_free(tmp);
  1511. }
  1512. }
  1513. }
  1514. /* Step three: for every entry A, see if there's an entry B making this one
  1515. * redundant later on. This is the case if A and B are of the same type
  1516. * (accept/reject), A is a subset of B, and there is no other entry of
  1517. * different type in between those two that intersects with A.
  1518. *
  1519. * Anybody want to double-check the logic here? XXX
  1520. */
  1521. for (i = 0; i < smartlist_len(dest)-1; ++i) {
  1522. ap = smartlist_get(dest, i);
  1523. for (j = i+1; j < smartlist_len(dest); ++j) {
  1524. // tor_assert(j > i); // j starts out at i+1; j only increases; i only
  1525. // // decreases.
  1526. tmp = smartlist_get(dest, j);
  1527. if (ap->policy_type != tmp->policy_type) {
  1528. if (addr_policy_intersects(ap, tmp))
  1529. break;
  1530. } else { /* policy_types are equal. */
  1531. if (addr_policy_covers(tmp, ap)) {
  1532. char p1[POLICY_BUF_LEN], p2[POLICY_BUF_LEN];
  1533. policy_write_item(p1, sizeof(p1), ap, 0);
  1534. policy_write_item(p2, sizeof(p2), tmp, 0);
  1535. log_debug(LD_CONFIG, "Removing exit policy %s. It is already "
  1536. "covered by %s.", p1, p2);
  1537. smartlist_del_keeporder(dest, i--);
  1538. addr_policy_free(ap);
  1539. break;
  1540. }
  1541. }
  1542. }
  1543. }
  1544. }
  1545. /** Reject private helper for policies_parse_exit_policy_internal: rejects
  1546. * publicly routable addresses on this exit relay.
  1547. *
  1548. * Add reject entries to the linked list *dest:
  1549. * - if configured_addresses is non-NULL, add entries that reject each
  1550. * tor_addr_t* in the list as a destination.
  1551. * - if reject_interface_addresses is true, add entries that reject each
  1552. * public IPv4 and IPv6 address of each interface on this machine.
  1553. * - if reject_configured_port_addresses is true, add entries that reject
  1554. * each IPv4 and IPv6 address configured for a port.
  1555. *
  1556. * IPv6 entries are only added if ipv6_exit is true. (All IPv6 addresses are
  1557. * already blocked by policies_parse_exit_policy_internal if ipv6_exit is
  1558. * false.)
  1559. *
  1560. * The list *dest is created as needed.
  1561. */
  1562. void
  1563. policies_parse_exit_policy_reject_private(
  1564. smartlist_t **dest,
  1565. int ipv6_exit,
  1566. const smartlist_t *configured_addresses,
  1567. int reject_interface_addresses,
  1568. int reject_configured_port_addresses)
  1569. {
  1570. tor_assert(dest);
  1571. /* Reject configured addresses, if they are from public netblocks. */
  1572. if (configured_addresses) {
  1573. addr_policy_append_reject_addr_list_filter(dest, configured_addresses,
  1574. 1, ipv6_exit);
  1575. }
  1576. /* Reject configured port addresses, if they are from public netblocks. */
  1577. if (reject_configured_port_addresses) {
  1578. const smartlist_t *port_addrs = get_configured_ports();
  1579. SMARTLIST_FOREACH_BEGIN(port_addrs, port_cfg_t *, port) {
  1580. /* Only reject port IP addresses, not port unix sockets */
  1581. if (!port->is_unix_addr) {
  1582. addr_policy_append_reject_addr_filter(dest, &port->addr, 1, ipv6_exit);
  1583. }
  1584. } SMARTLIST_FOREACH_END(port);
  1585. }
  1586. /* Reject local addresses from public netblocks on any interface. */
  1587. if (reject_interface_addresses) {
  1588. smartlist_t *public_addresses = NULL;
  1589. /* Reject public IPv4 addresses on any interface */
  1590. public_addresses = get_interface_address6_list(LOG_INFO, AF_INET, 0);
  1591. addr_policy_append_reject_addr_list_filter(dest, public_addresses, 1, 0);
  1592. free_interface_address6_list(public_addresses);
  1593. /* Don't look for IPv6 addresses if we're configured as IPv4-only */
  1594. if (ipv6_exit) {
  1595. /* Reject public IPv6 addresses on any interface */
  1596. public_addresses = get_interface_address6_list(LOG_INFO, AF_INET6, 0);
  1597. addr_policy_append_reject_addr_list_filter(dest, public_addresses, 0, 1);
  1598. free_interface_address6_list(public_addresses);
  1599. }
  1600. }
  1601. /* If addresses were added multiple times, remove all but one of them. */
  1602. if (*dest) {
  1603. exit_policy_remove_redundancies(*dest);
  1604. }
  1605. }
  1606. /**
  1607. * Iterate through <b>policy</b> looking for redundant entries. Log a
  1608. * warning message with the first redundant entry, if any is found.
  1609. */
  1610. static void
  1611. policies_log_first_redundant_entry(const smartlist_t *policy)
  1612. {
  1613. int found_final_effective_entry = 0;
  1614. int first_redundant_entry = 0;
  1615. tor_assert(policy);
  1616. SMARTLIST_FOREACH_BEGIN(policy, const addr_policy_t *, p) {
  1617. sa_family_t family;
  1618. int found_ipv4_wildcard = 0, found_ipv6_wildcard = 0;
  1619. const int i = p_sl_idx;
  1620. /* Look for accept/reject *[4|6|]:* entires */
  1621. if (p->prt_min <= 1 && p->prt_max == 65535 && p->maskbits == 0) {
  1622. family = tor_addr_family(&p->addr);
  1623. /* accept/reject *:* may have already been expanded into
  1624. * accept/reject *4:*,accept/reject *6:*
  1625. * But handle both forms.
  1626. */
  1627. if (family == AF_INET || family == AF_UNSPEC) {
  1628. found_ipv4_wildcard = 1;
  1629. }
  1630. if (family == AF_INET6 || family == AF_UNSPEC) {
  1631. found_ipv6_wildcard = 1;
  1632. }
  1633. }
  1634. /* We also find accept *4:*,reject *6:* ; and
  1635. * accept *4:*,<other policies>,accept *6:* ; and similar.
  1636. * That's ok, because they make any subsequent entries redundant. */
  1637. if (found_ipv4_wildcard && found_ipv6_wildcard) {
  1638. found_final_effective_entry = 1;
  1639. /* if we're not on the final entry in the list */
  1640. if (i < smartlist_len(policy) - 1) {
  1641. first_redundant_entry = i + 1;
  1642. }
  1643. break;
  1644. }
  1645. } SMARTLIST_FOREACH_END(p);
  1646. /* Work out if there are redundant trailing entries in the policy list */
  1647. if (found_final_effective_entry && first_redundant_entry > 0) {
  1648. const addr_policy_t *p;
  1649. /* Longest possible policy is
  1650. * "accept6 ffff:ffff:..255/128:10000-65535",
  1651. * which contains a max-length IPv6 address, plus 24 characters. */
  1652. char line[TOR_ADDR_BUF_LEN + 32];
  1653. tor_assert(first_redundant_entry < smartlist_len(policy));
  1654. p = smartlist_get(policy, first_redundant_entry);
  1655. /* since we've already parsed the policy into an addr_policy_t struct,
  1656. * we might not log exactly what the user typed in */
  1657. policy_write_item(line, TOR_ADDR_BUF_LEN + 32, p, 0);
  1658. log_warn(LD_DIR, "Exit policy '%s' and all following policies are "
  1659. "redundant, as it follows accept/reject *:* rules for both "
  1660. "IPv4 and IPv6. They will be removed from the exit policy. (Use "
  1661. "accept/reject *:* as the last entry in any exit policy.)",
  1662. line);
  1663. }
  1664. }
  1665. #define DEFAULT_EXIT_POLICY \
  1666. "reject *:25,reject *:119,reject *:135-139,reject *:445," \
  1667. "reject *:563,reject *:1214,reject *:4661-4666," \
  1668. "reject *:6346-6429,reject *:6699,reject *:6881-6999,accept *:*"
  1669. /** Parse the exit policy <b>cfg</b> into the linked list *<b>dest</b>.
  1670. *
  1671. * If <b>ipv6_exit</b> is false, prepend "reject *6:*" to the policy.
  1672. *
  1673. * If <b>rejectprivate</b> is true:
  1674. * - prepend "reject private:*" to the policy.
  1675. * - prepend entries that reject publicly routable addresses on this exit
  1676. * relay by calling policies_parse_exit_policy_reject_private
  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. /* Reject IPv4 and IPv6 publicly routable addresses on this exit relay */
  1705. policies_parse_exit_policy_reject_private(
  1706. dest, ipv6_exit,
  1707. configured_addresses,
  1708. reject_interface_addresses,
  1709. reject_configured_port_addresses);
  1710. }
  1711. if (parse_addr_policy(cfg, dest, -1))
  1712. return -1;
  1713. /* Before we add the default policy and final rejects, check to see if
  1714. * there are any lines after accept *:* or reject *:*. These lines have no
  1715. * effect, and are most likely an error. */
  1716. policies_log_first_redundant_entry(*dest);
  1717. if (add_default_policy) {
  1718. append_exit_policy_string(dest, DEFAULT_EXIT_POLICY);
  1719. } else {
  1720. append_exit_policy_string(dest, "reject *4:*");
  1721. append_exit_policy_string(dest, "reject *6:*");
  1722. }
  1723. exit_policy_remove_redundancies(*dest);
  1724. return 0;
  1725. }
  1726. /** Parse exit policy in <b>cfg</b> into <b>dest</b> smartlist.
  1727. *
  1728. * Prepend an entry that rejects all IPv6 destinations unless
  1729. * <b>EXIT_POLICY_IPV6_ENABLED</b> bit is set in <b>options</b> bitmask.
  1730. *
  1731. * If <b>EXIT_POLICY_REJECT_PRIVATE</b> bit is set in <b>options</b>:
  1732. * - prepend an entry that rejects all destinations in all netblocks
  1733. * reserved for private use.
  1734. * - prepend entries that reject publicly routable addresses on this exit
  1735. * relay by calling policies_parse_exit_policy_internal
  1736. *
  1737. * If <b>EXIT_POLICY_ADD_DEFAULT</b> bit is set in <b>options</b>, append
  1738. * default exit policy entries to <b>result</b> smartlist.
  1739. */
  1740. int
  1741. policies_parse_exit_policy(config_line_t *cfg, smartlist_t **dest,
  1742. exit_policy_parser_cfg_t options,
  1743. const smartlist_t *configured_addresses)
  1744. {
  1745. int ipv6_enabled = (options & EXIT_POLICY_IPV6_ENABLED) ? 1 : 0;
  1746. int reject_private = (options & EXIT_POLICY_REJECT_PRIVATE) ? 1 : 0;
  1747. int add_default = (options & EXIT_POLICY_ADD_DEFAULT) ? 1 : 0;
  1748. return policies_parse_exit_policy_internal(cfg,dest,ipv6_enabled,
  1749. reject_private,
  1750. configured_addresses,
  1751. reject_private,
  1752. reject_private,
  1753. add_default);
  1754. }
  1755. /** Helper function that adds a copy of addr to a smartlist as long as it is
  1756. * non-NULL and not tor_addr_is_null().
  1757. *
  1758. * The caller is responsible for freeing all the tor_addr_t* in the smartlist.
  1759. */
  1760. static void
  1761. policies_copy_addr_to_smartlist(smartlist_t *addr_list, const tor_addr_t *addr)
  1762. {
  1763. if (addr && !tor_addr_is_null(addr)) {
  1764. tor_addr_t *addr_copy = tor_malloc(sizeof(tor_addr_t));
  1765. tor_addr_copy(addr_copy, addr);
  1766. smartlist_add(addr_list, addr_copy);
  1767. }
  1768. }
  1769. /** Helper function that adds ipv4h_addr to a smartlist as a tor_addr_t *,
  1770. * as long as it is not tor_addr_is_null(), by converting it to a tor_addr_t
  1771. * and passing it to policies_add_addr_to_smartlist.
  1772. *
  1773. * The caller is responsible for freeing all the tor_addr_t* in the smartlist.
  1774. */
  1775. static void
  1776. policies_copy_ipv4h_to_smartlist(smartlist_t *addr_list, uint32_t ipv4h_addr)
  1777. {
  1778. if (ipv4h_addr) {
  1779. tor_addr_t ipv4_tor_addr;
  1780. tor_addr_from_ipv4h(&ipv4_tor_addr, ipv4h_addr);
  1781. policies_copy_addr_to_smartlist(addr_list, &ipv4_tor_addr);
  1782. }
  1783. }
  1784. /** Helper function that adds copies of
  1785. * or_options->OutboundBindAddressIPv[4|6]_ to a smartlist as tor_addr_t *, as
  1786. * long as or_options is non-NULL, and the addresses are not
  1787. * tor_addr_is_null(), by passing them to policies_add_addr_to_smartlist.
  1788. *
  1789. * The caller is responsible for freeing all the tor_addr_t* in the smartlist.
  1790. */
  1791. static void
  1792. policies_copy_outbound_addresses_to_smartlist(smartlist_t *addr_list,
  1793. const or_options_t *or_options)
  1794. {
  1795. if (or_options) {
  1796. policies_copy_addr_to_smartlist(addr_list,
  1797. &or_options->OutboundBindAddressIPv4_);
  1798. policies_copy_addr_to_smartlist(addr_list,
  1799. &or_options->OutboundBindAddressIPv6_);
  1800. }
  1801. }
  1802. /** Parse <b>ExitPolicy</b> member of <b>or_options</b> into <b>result</b>
  1803. * smartlist.
  1804. * If <b>or_options->IPv6Exit</b> is false, prepend an entry that
  1805. * rejects all IPv6 destinations.
  1806. *
  1807. * If <b>or_options->ExitPolicyRejectPrivate</b> is true:
  1808. * - prepend an entry that rejects all destinations in all netblocks reserved
  1809. * for private use.
  1810. * - if local_address is non-zero, treat it as a host-order IPv4 address, and
  1811. * add it to the list of configured addresses.
  1812. * - if ipv6_local_address is non-NULL, and not the null tor_addr_t, add it
  1813. * to the list of configured addresses.
  1814. * - if or_options->OutboundBindAddressIPv4_ is not the null tor_addr_t, add
  1815. * it to the list of configured addresses.
  1816. * - if or_options->OutboundBindAddressIPv6_ is not the null tor_addr_t, add
  1817. * it to the list of configured addresses.
  1818. *
  1819. * If <b>or_options->BridgeRelay</b> is false, append entries of default
  1820. * Tor exit policy into <b>result</b> smartlist.
  1821. *
  1822. * If or_options->ExitRelay is false, then make our exit policy into
  1823. * "reject *:*" regardless.
  1824. */
  1825. int
  1826. policies_parse_exit_policy_from_options(const or_options_t *or_options,
  1827. uint32_t local_address,
  1828. const tor_addr_t *ipv6_local_address,
  1829. smartlist_t **result)
  1830. {
  1831. exit_policy_parser_cfg_t parser_cfg = 0;
  1832. smartlist_t *configured_addresses = NULL;
  1833. int rv = 0;
  1834. /* Short-circuit for non-exit relays */
  1835. if (or_options->ExitRelay == 0) {
  1836. append_exit_policy_string(result, "reject *4:*");
  1837. append_exit_policy_string(result, "reject *6:*");
  1838. return 0;
  1839. }
  1840. configured_addresses = smartlist_new();
  1841. /* Configure the parser */
  1842. if (or_options->IPv6Exit) {
  1843. parser_cfg |= EXIT_POLICY_IPV6_ENABLED;
  1844. }
  1845. if (or_options->ExitPolicyRejectPrivate) {
  1846. parser_cfg |= EXIT_POLICY_REJECT_PRIVATE;
  1847. }
  1848. if (!or_options->BridgeRelay) {
  1849. parser_cfg |= EXIT_POLICY_ADD_DEFAULT;
  1850. }
  1851. /* Copy the configured addresses into the tor_addr_t* list */
  1852. policies_copy_ipv4h_to_smartlist(configured_addresses, local_address);
  1853. policies_copy_addr_to_smartlist(configured_addresses, ipv6_local_address);
  1854. policies_copy_outbound_addresses_to_smartlist(configured_addresses,
  1855. or_options);
  1856. rv = policies_parse_exit_policy(or_options->ExitPolicy, result, parser_cfg,
  1857. configured_addresses);
  1858. SMARTLIST_FOREACH(configured_addresses, tor_addr_t *, a, tor_free(a));
  1859. smartlist_free(configured_addresses);
  1860. return rv;
  1861. }
  1862. /** Add "reject *:*" to the end of the policy in *<b>dest</b>, allocating
  1863. * *<b>dest</b> as needed. */
  1864. void
  1865. policies_exit_policy_append_reject_star(smartlist_t **dest)
  1866. {
  1867. append_exit_policy_string(dest, "reject *4:*");
  1868. append_exit_policy_string(dest, "reject *6:*");
  1869. }
  1870. /** Replace the exit policy of <b>node</b> with reject *:* */
  1871. void
  1872. policies_set_node_exitpolicy_to_reject_all(node_t *node)
  1873. {
  1874. node->rejects_all = 1;
  1875. }
  1876. /** Return 1 if there is at least one /8 subnet in <b>policy</b> that
  1877. * allows exiting to <b>port</b>. Otherwise, return 0. */
  1878. static int
  1879. exit_policy_is_general_exit_helper(smartlist_t *policy, int port)
  1880. {
  1881. uint32_t mask, ip, i;
  1882. /* Is this /8 rejected (1), or undecided (0)? */
  1883. char subnet_status[256];
  1884. memset(subnet_status, 0, sizeof(subnet_status));
  1885. SMARTLIST_FOREACH_BEGIN(policy, addr_policy_t *, p) {
  1886. if (tor_addr_family(&p->addr) != AF_INET)
  1887. continue; /* IPv4 only for now */
  1888. if (p->prt_min > port || p->prt_max < port)
  1889. continue; /* Doesn't cover our port. */
  1890. mask = 0;
  1891. tor_assert(p->maskbits <= 32);
  1892. if (p->maskbits)
  1893. mask = UINT32_MAX<<(32-p->maskbits);
  1894. ip = tor_addr_to_ipv4h(&p->addr);
  1895. /* Calculate the first and last subnet that this exit policy touches
  1896. * and set it as loop boundaries. */
  1897. for (i = ((mask & ip)>>24); i <= (~((mask & ip) ^ mask)>>24); ++i) {
  1898. tor_addr_t addr;
  1899. if (subnet_status[i] != 0)
  1900. continue; /* We already reject some part of this /8 */
  1901. tor_addr_from_ipv4h(&addr, i<<24);
  1902. if (tor_addr_is_internal(&addr, 0))
  1903. continue; /* Local or non-routable addresses */
  1904. if (p->policy_type == ADDR_POLICY_ACCEPT) {
  1905. if (p->maskbits > 8)
  1906. continue; /* Narrower than a /8. */
  1907. /* We found an allowed subnet of at least size /8. Done
  1908. * for this port! */
  1909. return 1;
  1910. } else if (p->policy_type == ADDR_POLICY_REJECT) {
  1911. subnet_status[i] = 1;
  1912. }
  1913. }
  1914. } SMARTLIST_FOREACH_END(p);
  1915. return 0;
  1916. }
  1917. /** Return true iff <b>ri</b> is "useful as an exit node", meaning
  1918. * it allows exit to at least one /8 address space for at least
  1919. * two of ports 80, 443, and 6667. */
  1920. int
  1921. exit_policy_is_general_exit(smartlist_t *policy)
  1922. {
  1923. static const int ports[] = { 80, 443, 6667 };
  1924. int n_allowed = 0;
  1925. int i;
  1926. if (!policy) /*XXXX disallow NULL policies? */
  1927. return 0;
  1928. for (i = 0; i < 3; ++i) {
  1929. n_allowed += exit_policy_is_general_exit_helper(policy, ports[i]);
  1930. }
  1931. return n_allowed >= 2;
  1932. }
  1933. /** Return false if <b>policy</b> might permit access to some addr:port;
  1934. * otherwise if we are certain it rejects everything, return true. */
  1935. int
  1936. policy_is_reject_star(const smartlist_t *policy, sa_family_t family)
  1937. {
  1938. if (!policy) /*XXXX disallow NULL policies? */
  1939. return 1;
  1940. SMARTLIST_FOREACH_BEGIN(policy, addr_policy_t *, p) {
  1941. if (p->policy_type == ADDR_POLICY_ACCEPT &&
  1942. (tor_addr_family(&p->addr) == family ||
  1943. tor_addr_family(&p->addr) == AF_UNSPEC)) {
  1944. return 0;
  1945. } else if (p->policy_type == ADDR_POLICY_REJECT &&
  1946. p->prt_min <= 1 && p->prt_max == 65535 &&
  1947. p->maskbits == 0 &&
  1948. (tor_addr_family(&p->addr) == family ||
  1949. tor_addr_family(&p->addr) == AF_UNSPEC)) {
  1950. return 1;
  1951. }
  1952. } SMARTLIST_FOREACH_END(p);
  1953. return 1;
  1954. }
  1955. /** Write a single address policy to the buf_len byte buffer at buf. Return
  1956. * the number of characters written, or -1 on failure. */
  1957. int
  1958. policy_write_item(char *buf, size_t buflen, const addr_policy_t *policy,
  1959. int format_for_desc)
  1960. {
  1961. size_t written = 0;
  1962. char addrbuf[TOR_ADDR_BUF_LEN];
  1963. const char *addrpart;
  1964. int result;
  1965. const int is_accept = policy->policy_type == ADDR_POLICY_ACCEPT;
  1966. const sa_family_t family = tor_addr_family(&policy->addr);
  1967. const int is_ip6 = (family == AF_INET6);
  1968. tor_addr_to_str(addrbuf, &policy->addr, sizeof(addrbuf), 1);
  1969. /* write accept/reject 1.2.3.4 */
  1970. if (policy->is_private) {
  1971. addrpart = "private";
  1972. } else if (policy->maskbits == 0) {
  1973. if (format_for_desc)
  1974. addrpart = "*";
  1975. else if (family == AF_INET6)
  1976. addrpart = "*6";
  1977. else if (family == AF_INET)
  1978. addrpart = "*4";
  1979. else
  1980. addrpart = "*";
  1981. } else {
  1982. addrpart = addrbuf;
  1983. }
  1984. result = tor_snprintf(buf, buflen, "%s%s %s",
  1985. is_accept ? "accept" : "reject",
  1986. (is_ip6&&format_for_desc)?"6":"",
  1987. addrpart);
  1988. if (result < 0)
  1989. return -1;
  1990. written += strlen(buf);
  1991. /* If the maskbits is 32 (IPv4) or 128 (IPv6) we don't need to give it. If
  1992. the mask is 0, we already wrote "*". */
  1993. if (policy->maskbits < (is_ip6?128:32) && policy->maskbits > 0) {
  1994. if (tor_snprintf(buf+written, buflen-written, "/%d", policy->maskbits)<0)
  1995. return -1;
  1996. written += strlen(buf+written);
  1997. }
  1998. if (policy->prt_min <= 1 && policy->prt_max == 65535) {
  1999. /* There is no port set; write ":*" */
  2000. if (written+4 > buflen)
  2001. return -1;
  2002. strlcat(buf+written, ":*", buflen-written);
  2003. written += 2;
  2004. } else if (policy->prt_min == policy->prt_max) {
  2005. /* There is only one port; write ":80". */
  2006. result = tor_snprintf(buf+written, buflen-written, ":%d", policy->prt_min);
  2007. if (result<0)
  2008. return -1;
  2009. written += result;
  2010. } else {
  2011. /* There is a range of ports; write ":79-80". */
  2012. result = tor_snprintf(buf+written, buflen-written, ":%d-%d",
  2013. policy->prt_min, policy->prt_max);
  2014. if (result<0)
  2015. return -1;
  2016. written += result;
  2017. }
  2018. if (written < buflen)
  2019. buf[written] = '\0';
  2020. else
  2021. return -1;
  2022. return (int)written;
  2023. }
  2024. /** Create a new exit policy summary, initially only with a single
  2025. * port 1-64k item */
  2026. /* XXXX This entire thing will do most stuff in O(N^2), or worse. Use an
  2027. * RB-tree if that turns out to matter. */
  2028. static smartlist_t *
  2029. policy_summary_create(void)
  2030. {
  2031. smartlist_t *summary;
  2032. policy_summary_item_t* item;
  2033. item = tor_malloc_zero(sizeof(policy_summary_item_t));
  2034. item->prt_min = 1;
  2035. item->prt_max = 65535;
  2036. item->reject_count = 0;
  2037. item->accepted = 0;
  2038. summary = smartlist_new();
  2039. smartlist_add(summary, item);
  2040. return summary;
  2041. }
  2042. /** Split the summary item in <b>item</b> at the port <b>new_starts</b>.
  2043. * The current item is changed to end at new-starts - 1, the new item
  2044. * copies reject_count and accepted from the old item,
  2045. * starts at new_starts and ends at the port where the original item
  2046. * previously ended.
  2047. */
  2048. static policy_summary_item_t*
  2049. policy_summary_item_split(policy_summary_item_t* old, uint16_t new_starts)
  2050. {
  2051. policy_summary_item_t* new;
  2052. new = tor_malloc_zero(sizeof(policy_summary_item_t));
  2053. new->prt_min = new_starts;
  2054. new->prt_max = old->prt_max;
  2055. new->reject_count = old->reject_count;
  2056. new->accepted = old->accepted;
  2057. old->prt_max = new_starts-1;
  2058. tor_assert(old->prt_min <= old->prt_max);
  2059. tor_assert(new->prt_min <= new->prt_max);
  2060. return new;
  2061. }
  2062. /* XXXX Nick says I'm going to hell for this. If he feels charitably towards
  2063. * my immortal soul, he can clean it up himself. */
  2064. #define AT(x) ((policy_summary_item_t*)smartlist_get(summary, x))
  2065. #define REJECT_CUTOFF_COUNT (1<<25)
  2066. /** Split an exit policy summary so that prt_min and prt_max
  2067. * fall at exactly the start and end of an item respectively.
  2068. */
  2069. static int
  2070. policy_summary_split(smartlist_t *summary,
  2071. uint16_t prt_min, uint16_t prt_max)
  2072. {
  2073. int start_at_index;
  2074. int i = 0;
  2075. while (AT(i)->prt_max < prt_min)
  2076. i++;
  2077. if (AT(i)->prt_min != prt_min) {
  2078. policy_summary_item_t* new_item;
  2079. new_item = policy_summary_item_split(AT(i), prt_min);
  2080. smartlist_insert(summary, i+1, new_item);
  2081. i++;
  2082. }
  2083. start_at_index = i;
  2084. while (AT(i)->prt_max < prt_max)
  2085. i++;
  2086. if (AT(i)->prt_max != prt_max) {
  2087. policy_summary_item_t* new_item;
  2088. new_item = policy_summary_item_split(AT(i), prt_max+1);
  2089. smartlist_insert(summary, i+1, new_item);
  2090. }
  2091. return start_at_index;
  2092. }
  2093. /** Mark port ranges as accepted if they are below the reject_count */
  2094. static void
  2095. policy_summary_accept(smartlist_t *summary,
  2096. uint16_t prt_min, uint16_t prt_max)
  2097. {
  2098. int i = policy_summary_split(summary, prt_min, prt_max);
  2099. while (i < smartlist_len(summary) &&
  2100. AT(i)->prt_max <= prt_max) {
  2101. if (!AT(i)->accepted &&
  2102. AT(i)->reject_count <= REJECT_CUTOFF_COUNT)
  2103. AT(i)->accepted = 1;
  2104. i++;
  2105. }
  2106. tor_assert(i < smartlist_len(summary) || prt_max==65535);
  2107. }
  2108. /** Count the number of addresses in a network with prefixlen maskbits
  2109. * against the given portrange. */
  2110. static void
  2111. policy_summary_reject(smartlist_t *summary,
  2112. maskbits_t maskbits,
  2113. uint16_t prt_min, uint16_t prt_max)
  2114. {
  2115. int i = policy_summary_split(summary, prt_min, prt_max);
  2116. /* XXX: ipv4 specific */
  2117. uint64_t count = (U64_LITERAL(1) << (32-maskbits));
  2118. while (i < smartlist_len(summary) &&
  2119. AT(i)->prt_max <= prt_max) {
  2120. AT(i)->reject_count += count;
  2121. i++;
  2122. }
  2123. tor_assert(i < smartlist_len(summary) || prt_max==65535);
  2124. }
  2125. /** Add a single exit policy item to our summary:
  2126. * If it is an accept ignore it unless it is for all IP addresses
  2127. * ("*"), i.e. it's prefixlen/maskbits is 0, else call
  2128. * policy_summary_accept().
  2129. * If it's a reject ignore it if it is about one of the private
  2130. * networks, else call policy_summary_reject().
  2131. */
  2132. static void
  2133. policy_summary_add_item(smartlist_t *summary, addr_policy_t *p)
  2134. {
  2135. if (p->policy_type == ADDR_POLICY_ACCEPT) {
  2136. if (p->maskbits == 0) {
  2137. policy_summary_accept(summary, p->prt_min, p->prt_max);
  2138. }
  2139. } else if (p->policy_type == ADDR_POLICY_REJECT) {
  2140. int is_private = 0;
  2141. int i;
  2142. for (i = 0; private_nets[i]; ++i) {
  2143. tor_addr_t addr;
  2144. maskbits_t maskbits;
  2145. if (tor_addr_parse_mask_ports(private_nets[i], 0, &addr,
  2146. &maskbits, NULL, NULL)<0) {
  2147. tor_assert(0);
  2148. }
  2149. if (tor_addr_compare(&p->addr, &addr, CMP_EXACT) == 0 &&
  2150. p->maskbits == maskbits) {
  2151. is_private = 1;
  2152. break;
  2153. }
  2154. }
  2155. if (!is_private) {
  2156. policy_summary_reject(summary, p->maskbits, p->prt_min, p->prt_max);
  2157. }
  2158. } else
  2159. tor_assert(0);
  2160. }
  2161. /** Create a string representing a summary for an exit policy.
  2162. * The summary will either be an "accept" plus a comma-separated list of port
  2163. * ranges or a "reject" plus port-ranges, depending on which is shorter.
  2164. *
  2165. * If no exits are allowed at all then "reject 1-65535" is returned. If no
  2166. * ports are blocked instead of "reject " we return "accept 1-65535". (These
  2167. * are an exception to the shorter-representation-wins rule).
  2168. */
  2169. char *
  2170. policy_summarize(smartlist_t *policy, sa_family_t family)
  2171. {
  2172. smartlist_t *summary = policy_summary_create();
  2173. smartlist_t *accepts, *rejects;
  2174. int i, last, start_prt;
  2175. size_t accepts_len, rejects_len;
  2176. char *accepts_str = NULL, *rejects_str = NULL, *shorter_str, *result;
  2177. const char *prefix;
  2178. tor_assert(policy);
  2179. /* Create the summary list */
  2180. SMARTLIST_FOREACH_BEGIN(policy, addr_policy_t *, p) {
  2181. sa_family_t f = tor_addr_family(&p->addr);
  2182. if (f != AF_INET && f != AF_INET6) {
  2183. log_warn(LD_BUG, "Weird family when summarizing address policy");
  2184. }
  2185. if (f != family)
  2186. continue;
  2187. /* XXXX-ipv6 More family work is needed */
  2188. policy_summary_add_item(summary, p);
  2189. } SMARTLIST_FOREACH_END(p);
  2190. /* Now create two lists of strings, one for accepted and one
  2191. * for rejected ports. We take care to merge ranges so that
  2192. * we avoid getting stuff like "1-4,5-9,10", instead we want
  2193. * "1-10"
  2194. */
  2195. i = 0;
  2196. start_prt = 1;
  2197. accepts = smartlist_new();
  2198. rejects = smartlist_new();
  2199. while (1) {
  2200. last = i == smartlist_len(summary)-1;
  2201. if (last ||
  2202. AT(i)->accepted != AT(i+1)->accepted) {
  2203. char buf[POLICY_BUF_LEN];
  2204. if (start_prt == AT(i)->prt_max)
  2205. tor_snprintf(buf, sizeof(buf), "%d", start_prt);
  2206. else
  2207. tor_snprintf(buf, sizeof(buf), "%d-%d", start_prt, AT(i)->prt_max);
  2208. if (AT(i)->accepted)
  2209. smartlist_add(accepts, tor_strdup(buf));
  2210. else
  2211. smartlist_add(rejects, tor_strdup(buf));
  2212. if (last)
  2213. break;
  2214. start_prt = AT(i+1)->prt_min;
  2215. };
  2216. i++;
  2217. };
  2218. /* Figure out which of the two stringlists will be shorter and use
  2219. * that to build the result
  2220. */
  2221. if (smartlist_len(accepts) == 0) { /* no exits at all */
  2222. result = tor_strdup("reject 1-65535");
  2223. goto cleanup;
  2224. }
  2225. if (smartlist_len(rejects) == 0) { /* no rejects at all */
  2226. result = tor_strdup("accept 1-65535");
  2227. goto cleanup;
  2228. }
  2229. accepts_str = smartlist_join_strings(accepts, ",", 0, &accepts_len);
  2230. rejects_str = smartlist_join_strings(rejects, ",", 0, &rejects_len);
  2231. if (rejects_len > MAX_EXITPOLICY_SUMMARY_LEN-strlen("reject")-1 &&
  2232. accepts_len > MAX_EXITPOLICY_SUMMARY_LEN-strlen("accept")-1) {
  2233. char *c;
  2234. shorter_str = accepts_str;
  2235. prefix = "accept";
  2236. c = shorter_str + (MAX_EXITPOLICY_SUMMARY_LEN-strlen(prefix)-1);
  2237. while (*c != ',' && c >= shorter_str)
  2238. c--;
  2239. tor_assert(c >= shorter_str);
  2240. tor_assert(*c == ',');
  2241. *c = '\0';
  2242. } else if (rejects_len < accepts_len) {
  2243. shorter_str = rejects_str;
  2244. prefix = "reject";
  2245. } else {
  2246. shorter_str = accepts_str;
  2247. prefix = "accept";
  2248. }
  2249. tor_asprintf(&result, "%s %s", prefix, shorter_str);
  2250. cleanup:
  2251. /* cleanup */
  2252. SMARTLIST_FOREACH(summary, policy_summary_item_t *, s, tor_free(s));
  2253. smartlist_free(summary);
  2254. tor_free(accepts_str);
  2255. SMARTLIST_FOREACH(accepts, char *, s, tor_free(s));
  2256. smartlist_free(accepts);
  2257. tor_free(rejects_str);
  2258. SMARTLIST_FOREACH(rejects, char *, s, tor_free(s));
  2259. smartlist_free(rejects);
  2260. return result;
  2261. }
  2262. /** Convert a summarized policy string into a short_policy_t. Return NULL
  2263. * if the string is not well-formed. */
  2264. short_policy_t *
  2265. parse_short_policy(const char *summary)
  2266. {
  2267. const char *orig_summary = summary;
  2268. short_policy_t *result;
  2269. int is_accept;
  2270. int n_entries;
  2271. short_policy_entry_t entries[MAX_EXITPOLICY_SUMMARY_LEN]; /* overkill */
  2272. const char *next;
  2273. if (!strcmpstart(summary, "accept ")) {
  2274. is_accept = 1;
  2275. summary += strlen("accept ");
  2276. } else if (!strcmpstart(summary, "reject ")) {
  2277. is_accept = 0;
  2278. summary += strlen("reject ");
  2279. } else {
  2280. log_fn(LOG_PROTOCOL_WARN, LD_DIR, "Unrecognized policy summary keyword");
  2281. return NULL;
  2282. }
  2283. n_entries = 0;
  2284. for ( ; *summary; summary = next) {
  2285. const char *comma = strchr(summary, ',');
  2286. unsigned low, high;
  2287. char dummy;
  2288. char ent_buf[32];
  2289. size_t len;
  2290. next = comma ? comma+1 : strchr(summary, '\0');
  2291. len = comma ? (size_t)(comma - summary) : strlen(summary);
  2292. if (n_entries == MAX_EXITPOLICY_SUMMARY_LEN) {
  2293. log_fn(LOG_PROTOCOL_WARN, LD_DIR, "Impossibly long policy summary %s",
  2294. escaped(orig_summary));
  2295. return NULL;
  2296. }
  2297. if (! TOR_ISDIGIT(*summary) || len > (sizeof(ent_buf)-1)) {
  2298. /* unrecognized entry format. skip it. */
  2299. continue;
  2300. }
  2301. if (len < 1) {
  2302. /* empty; skip it. */
  2303. /* XXX This happens to be unreachable, since if len==0, then *summary is
  2304. * ',' or '\0', and the TOR_ISDIGIT test above would have failed. */
  2305. continue;
  2306. }
  2307. memcpy(ent_buf, summary, len);
  2308. ent_buf[len] = '\0';
  2309. if (tor_sscanf(ent_buf, "%u-%u%c", &low, &high, &dummy) == 2) {
  2310. if (low<1 || low>65535 || high<1 || high>65535 || low>high) {
  2311. log_fn(LOG_PROTOCOL_WARN, LD_DIR,
  2312. "Found bad entry in policy summary %s", escaped(orig_summary));
  2313. return NULL;
  2314. }
  2315. } else if (tor_sscanf(ent_buf, "%u%c", &low, &dummy) == 1) {
  2316. if (low<1 || low>65535) {
  2317. log_fn(LOG_PROTOCOL_WARN, LD_DIR,
  2318. "Found bad entry in policy summary %s", escaped(orig_summary));
  2319. return NULL;
  2320. }
  2321. high = low;
  2322. } else {
  2323. log_fn(LOG_PROTOCOL_WARN, LD_DIR,"Found bad entry in policy summary %s",
  2324. escaped(orig_summary));
  2325. return NULL;
  2326. }
  2327. entries[n_entries].min_port = low;
  2328. entries[n_entries].max_port = high;
  2329. n_entries++;
  2330. }
  2331. if (n_entries == 0) {
  2332. log_fn(LOG_PROTOCOL_WARN, LD_DIR,
  2333. "Found no port-range entries in summary %s", escaped(orig_summary));
  2334. return NULL;
  2335. }
  2336. {
  2337. size_t size = STRUCT_OFFSET(short_policy_t, entries) +
  2338. sizeof(short_policy_entry_t)*(n_entries);
  2339. result = tor_malloc_zero(size);
  2340. tor_assert( (char*)&result->entries[n_entries-1] < ((char*)result)+size);
  2341. }
  2342. result->is_accept = is_accept;
  2343. result->n_entries = n_entries;
  2344. memcpy(result->entries, entries, sizeof(short_policy_entry_t)*n_entries);
  2345. return result;
  2346. }
  2347. /** Write <b>policy</b> back out into a string. Used only for unit tests
  2348. * currently. */
  2349. char *
  2350. write_short_policy(const short_policy_t *policy)
  2351. {
  2352. int i;
  2353. char *answer;
  2354. smartlist_t *sl = smartlist_new();
  2355. smartlist_add_asprintf(sl, "%s", policy->is_accept ? "accept " : "reject ");
  2356. for (i=0; i < policy->n_entries; i++) {
  2357. const short_policy_entry_t *e = &policy->entries[i];
  2358. if (e->min_port == e->max_port) {
  2359. smartlist_add_asprintf(sl, "%d", e->min_port);
  2360. } else {
  2361. smartlist_add_asprintf(sl, "%d-%d", e->min_port, e->max_port);
  2362. }
  2363. if (i < policy->n_entries-1)
  2364. smartlist_add(sl, tor_strdup(","));
  2365. }
  2366. answer = smartlist_join_strings(sl, "", 0, NULL);
  2367. SMARTLIST_FOREACH(sl, char *, a, tor_free(a));
  2368. smartlist_free(sl);
  2369. return answer;
  2370. }
  2371. /** Release all storage held in <b>policy</b>. */
  2372. void
  2373. short_policy_free(short_policy_t *policy)
  2374. {
  2375. tor_free(policy);
  2376. }
  2377. /** See whether the <b>addr</b>:<b>port</b> address is likely to be accepted
  2378. * or rejected by the summarized policy <b>policy</b>. Return values are as
  2379. * for compare_tor_addr_to_addr_policy. Unlike the regular addr_policy
  2380. * functions, requires the <b>port</b> be specified. */
  2381. addr_policy_result_t
  2382. compare_tor_addr_to_short_policy(const tor_addr_t *addr, uint16_t port,
  2383. const short_policy_t *policy)
  2384. {
  2385. int i;
  2386. int found_match = 0;
  2387. int accept;
  2388. tor_assert(port != 0);
  2389. if (addr && tor_addr_is_null(addr))
  2390. addr = NULL; /* Unspec means 'no address at all,' in this context. */
  2391. if (addr && get_options()->ClientRejectInternalAddresses &&
  2392. (tor_addr_is_internal(addr, 0) || tor_addr_is_loopback(addr)))
  2393. return ADDR_POLICY_REJECTED;
  2394. for (i=0; i < policy->n_entries; ++i) {
  2395. const short_policy_entry_t *e = &policy->entries[i];
  2396. if (e->min_port <= port && port <= e->max_port) {
  2397. found_match = 1;
  2398. break;
  2399. }
  2400. }
  2401. if (found_match)
  2402. accept = policy->is_accept;
  2403. else
  2404. accept = ! policy->is_accept;
  2405. /* ???? are these right? -NM */
  2406. /* We should be sure not to return ADDR_POLICY_ACCEPTED in the accept
  2407. * case here, because it would cause clients to believe that the node
  2408. * allows exit enclaving. Trying it anyway would open up a cool attack
  2409. * where the node refuses due to exitpolicy, the client reacts in
  2410. * surprise by rewriting the node's exitpolicy to reject *:*, and then
  2411. * an adversary targets users by causing them to attempt such connections
  2412. * to 98% of the exits.
  2413. *
  2414. * Once microdescriptors can handle addresses in special cases (e.g. if
  2415. * we ever solve ticket 1774), we can provide certainty here. -RD */
  2416. if (accept)
  2417. return ADDR_POLICY_PROBABLY_ACCEPTED;
  2418. else
  2419. return ADDR_POLICY_REJECTED;
  2420. }
  2421. /** Return true iff <b>policy</b> seems reject all ports */
  2422. int
  2423. short_policy_is_reject_star(const short_policy_t *policy)
  2424. {
  2425. /* This doesn't need to be as much on the lookout as policy_is_reject_star,
  2426. * since policy summaries are from the consensus or from consensus
  2427. * microdescs.
  2428. */
  2429. tor_assert(policy);
  2430. /* Check for an exact match of "reject 1-65535". */
  2431. return (policy->is_accept == 0 && policy->n_entries == 1 &&
  2432. policy->entries[0].min_port == 1 &&
  2433. policy->entries[0].max_port == 65535);
  2434. }
  2435. /** Decide whether addr:port is probably or definitely accepted or rejected by
  2436. * <b>node</b>. See compare_tor_addr_to_addr_policy for details on addr/port
  2437. * interpretation. */
  2438. addr_policy_result_t
  2439. compare_tor_addr_to_node_policy(const tor_addr_t *addr, uint16_t port,
  2440. const node_t *node)
  2441. {
  2442. if (node->rejects_all)
  2443. return ADDR_POLICY_REJECTED;
  2444. if (addr && tor_addr_family(addr) == AF_INET6) {
  2445. const short_policy_t *p = NULL;
  2446. if (node->ri)
  2447. p = node->ri->ipv6_exit_policy;
  2448. else if (node->md)
  2449. p = node->md->ipv6_exit_policy;
  2450. if (p)
  2451. return compare_tor_addr_to_short_policy(addr, port, p);
  2452. else
  2453. return ADDR_POLICY_REJECTED;
  2454. }
  2455. if (node->ri) {
  2456. return compare_tor_addr_to_addr_policy(addr, port, node->ri->exit_policy);
  2457. } else if (node->md) {
  2458. if (node->md->exit_policy == NULL)
  2459. return ADDR_POLICY_REJECTED;
  2460. else
  2461. return compare_tor_addr_to_short_policy(addr, port,
  2462. node->md->exit_policy);
  2463. } else {
  2464. return ADDR_POLICY_PROBABLY_REJECTED;
  2465. }
  2466. }
  2467. /**
  2468. * Given <b>policy_list</b>, a list of addr_policy_t, produce a string
  2469. * representation of the list.
  2470. * If <b>include_ipv4</b> is true, include IPv4 entries.
  2471. * If <b>include_ipv6</b> is true, include IPv6 entries.
  2472. */
  2473. char *
  2474. policy_dump_to_string(const smartlist_t *policy_list,
  2475. int include_ipv4,
  2476. int include_ipv6)
  2477. {
  2478. smartlist_t *policy_string_list;
  2479. char *policy_string = NULL;
  2480. policy_string_list = smartlist_new();
  2481. SMARTLIST_FOREACH_BEGIN(policy_list, addr_policy_t *, tmpe) {
  2482. char *pbuf;
  2483. int bytes_written_to_pbuf;
  2484. if ((tor_addr_family(&tmpe->addr) == AF_INET6) && (!include_ipv6)) {
  2485. continue; /* Don't include IPv6 parts of address policy */
  2486. }
  2487. if ((tor_addr_family(&tmpe->addr) == AF_INET) && (!include_ipv4)) {
  2488. continue; /* Don't include IPv4 parts of address policy */
  2489. }
  2490. pbuf = tor_malloc(POLICY_BUF_LEN);
  2491. bytes_written_to_pbuf = policy_write_item(pbuf,POLICY_BUF_LEN, tmpe, 1);
  2492. if (bytes_written_to_pbuf < 0) {
  2493. log_warn(LD_BUG, "policy_dump_to_string ran out of room!");
  2494. tor_free(pbuf);
  2495. goto done;
  2496. }
  2497. smartlist_add(policy_string_list,pbuf);
  2498. } SMARTLIST_FOREACH_END(tmpe);
  2499. policy_string = smartlist_join_strings(policy_string_list, "\n", 0, NULL);
  2500. done:
  2501. SMARTLIST_FOREACH(policy_string_list, char *, str, tor_free(str));
  2502. smartlist_free(policy_string_list);
  2503. return policy_string;
  2504. }
  2505. /** Implementation for GETINFO control command: knows the answer for questions
  2506. * about "exit-policy/..." */
  2507. int
  2508. getinfo_helper_policies(control_connection_t *conn,
  2509. const char *question, char **answer,
  2510. const char **errmsg)
  2511. {
  2512. (void) conn;
  2513. (void) errmsg;
  2514. if (!strcmp(question, "exit-policy/default")) {
  2515. *answer = tor_strdup(DEFAULT_EXIT_POLICY);
  2516. } else if (!strcmp(question, "exit-policy/reject-private/default")) {
  2517. smartlist_t *private_policy_strings;
  2518. const char **priv = private_nets;
  2519. private_policy_strings = smartlist_new();
  2520. while (*priv != NULL) {
  2521. /* IPv6 addresses are in "[]" and contain ":",
  2522. * IPv4 addresses are not in "[]" and contain "." */
  2523. smartlist_add_asprintf(private_policy_strings, "reject %s:*", *priv);
  2524. priv++;
  2525. }
  2526. *answer = smartlist_join_strings(private_policy_strings,
  2527. ",", 0, NULL);
  2528. SMARTLIST_FOREACH(private_policy_strings, char *, str, tor_free(str));
  2529. smartlist_free(private_policy_strings);
  2530. } else if (!strcmp(question, "exit-policy/reject-private/relay")) {
  2531. const or_options_t *options = get_options();
  2532. const routerinfo_t *me = router_get_my_routerinfo();
  2533. if (!me) {
  2534. *errmsg = "router_get_my_routerinfo returned NULL";
  2535. return -1;
  2536. }
  2537. if (!options->ExitPolicyRejectPrivate) {
  2538. *answer = tor_strdup("");
  2539. return 0;
  2540. }
  2541. smartlist_t *private_policy_list = smartlist_new();
  2542. smartlist_t *configured_addresses = smartlist_new();
  2543. /* Copy the configured addresses into the tor_addr_t* list */
  2544. policies_copy_ipv4h_to_smartlist(configured_addresses, me->addr);
  2545. policies_copy_addr_to_smartlist(configured_addresses, &me->ipv6_addr);
  2546. policies_copy_outbound_addresses_to_smartlist(configured_addresses,
  2547. options);
  2548. policies_parse_exit_policy_reject_private(
  2549. &private_policy_list,
  2550. options->IPv6Exit,
  2551. configured_addresses,
  2552. 1, 1);
  2553. *answer = policy_dump_to_string(private_policy_list, 1, 1);
  2554. addr_policy_list_free(private_policy_list);
  2555. SMARTLIST_FOREACH(configured_addresses, tor_addr_t *, a, tor_free(a));
  2556. smartlist_free(configured_addresses);
  2557. } else if (!strcmpstart(question, "exit-policy/")) {
  2558. const routerinfo_t *me = router_get_my_routerinfo();
  2559. int include_ipv4 = 0;
  2560. int include_ipv6 = 0;
  2561. if (!strcmp(question, "exit-policy/ipv4")) {
  2562. include_ipv4 = 1;
  2563. } else if (!strcmp(question, "exit-policy/ipv6")) {
  2564. include_ipv6 = 1;
  2565. } else if (!strcmp(question, "exit-policy/full")) {
  2566. include_ipv4 = include_ipv6 = 1;
  2567. } else {
  2568. return 0; /* No such key. */
  2569. }
  2570. if (!me) {
  2571. *errmsg = "router_get_my_routerinfo returned NULL";
  2572. return -1;
  2573. }
  2574. *answer = router_dump_exit_policy_to_string(me,include_ipv4,include_ipv6);
  2575. }
  2576. return 0;
  2577. }
  2578. /** Release all storage held by <b>p</b>. */
  2579. void
  2580. addr_policy_list_free(smartlist_t *lst)
  2581. {
  2582. if (!lst)
  2583. return;
  2584. SMARTLIST_FOREACH(lst, addr_policy_t *, policy, addr_policy_free(policy));
  2585. smartlist_free(lst);
  2586. }
  2587. /** Release all storage held by <b>p</b>. */
  2588. void
  2589. addr_policy_free(addr_policy_t *p)
  2590. {
  2591. if (!p)
  2592. return;
  2593. if (--p->refcnt <= 0) {
  2594. if (p->is_canonical) {
  2595. policy_map_ent_t search, *found;
  2596. search.policy = p;
  2597. found = HT_REMOVE(policy_map, &policy_root, &search);
  2598. if (found) {
  2599. tor_assert(p == found->policy);
  2600. tor_free(found);
  2601. }
  2602. }
  2603. tor_free(p);
  2604. }
  2605. }
  2606. /** Release all storage held by policy variables. */
  2607. void
  2608. policies_free_all(void)
  2609. {
  2610. addr_policy_list_free(reachable_or_addr_policy);
  2611. reachable_or_addr_policy = NULL;
  2612. addr_policy_list_free(reachable_dir_addr_policy);
  2613. reachable_dir_addr_policy = NULL;
  2614. addr_policy_list_free(socks_policy);
  2615. socks_policy = NULL;
  2616. addr_policy_list_free(dir_policy);
  2617. dir_policy = NULL;
  2618. addr_policy_list_free(authdir_reject_policy);
  2619. authdir_reject_policy = NULL;
  2620. addr_policy_list_free(authdir_invalid_policy);
  2621. authdir_invalid_policy = NULL;
  2622. addr_policy_list_free(authdir_badexit_policy);
  2623. authdir_badexit_policy = NULL;
  2624. if (!HT_EMPTY(&policy_root)) {
  2625. policy_map_ent_t **ent;
  2626. int n = 0;
  2627. char buf[POLICY_BUF_LEN];
  2628. log_warn(LD_MM, "Still had %d address policies cached at shutdown.",
  2629. (int)HT_SIZE(&policy_root));
  2630. /* Note the first 10 cached policies to try to figure out where they
  2631. * might be coming from. */
  2632. HT_FOREACH(ent, policy_map, &policy_root) {
  2633. if (++n > 10)
  2634. break;
  2635. if (policy_write_item(buf, sizeof(buf), (*ent)->policy, 0) >= 0)
  2636. log_warn(LD_MM," %d [%d]: %s", n, (*ent)->policy->refcnt, buf);
  2637. }
  2638. }
  2639. HT_CLEAR(policy_map, &policy_root);
  2640. }