commit 8da24c99bdb90b04a05d5bccf5bcff1218174b75 Author: Nick Mathewson nickm@torproject.org Date: Tue Nov 15 07:49:06 2016 -0500
Split bridge functions into a new module.
This patch is just: * Code movement * Adding headers here and there as needed * Adding a bridges_free_all() with a call to it.
It breaks compilation, since the bridge code needed to make exactly 2 calls into entrynodes.c internals. I'll fix those in the next commit. --- src/or/bridges.c | 809 +++++++++++++++++++++++++++++++++++++++++++++ src/or/bridges.h | 54 +++ src/or/circuitbuild.c | 1 + src/or/circuituse.c | 1 + src/or/config.c | 1 + src/or/connection.c | 1 + src/or/connection_or.c | 1 + src/or/control.c | 1 + src/or/directory.c | 1 + src/or/entrynodes.c | 776 +------------------------------------------ src/or/entrynodes.h | 34 -- src/or/include.am | 2 + src/or/main.c | 2 + src/or/networkstatus.c | 1 + src/or/routerlist.c | 1 + src/or/transports.c | 2 +- src/test/test_config.c | 1 + src/test/test_controller.c | 1 + 18 files changed, 880 insertions(+), 810 deletions(-)
diff --git a/src/or/bridges.c b/src/or/bridges.c new file mode 100644 index 0000000..73510cf --- /dev/null +++ b/src/or/bridges.c @@ -0,0 +1,809 @@ +/* Copyright (c) 2001 Matej Pfajfar. + * Copyright (c) 2001-2004, Roger Dingledine. + * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. + * Copyright (c) 2007-2016, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +/** + * \file bridges.c + * \brief Code to manage bridges and bridge selection. + * + * Bridges are fixed entry nodes, used for censorship circumvention. + **/ + +#include "or.h" +#include "bridges.h" +#include "circuitbuild.h" +#include "config.h" +#include "connection.h" +#include "directory.h" +#include "entrynodes.h" +#include "nodelist.h" +#include "policies.h" +#include "router.h" +#include "routerlist.h" +#include "routerset.h" +#include "transports.h" + +/** Information about a configured bridge. Currently this just matches the + * ones in the torrc file, but one day we may be able to learn about new + * bridges on our own, and remember them in the state file. */ +typedef struct { + /** Address of the bridge. */ + tor_addr_t addr; + /** TLS port for the bridge. */ + uint16_t port; + /** Boolean: We are re-parsing our bridge list, and we are going to remove + * this one if we don't find it in the list of configured bridges. */ + unsigned marked_for_removal : 1; + /** Expected identity digest, or all zero bytes if we don't know what the + * digest should be. */ + char identity[DIGEST_LEN]; + + /** Name of pluggable transport protocol taken from its config line. */ + char *transport_name; + + /** When should we next try to fetch a descriptor for this bridge? */ + download_status_t fetch_status; + + /** A smartlist of k=v values to be passed to the SOCKS proxy, if + transports are used for this bridge. */ + smartlist_t *socks_args; +} bridge_info_t; + +static void bridge_free(bridge_info_t *bridge); +static int num_bridges_usable(void); + +/** A list of configured bridges. Whenever we actually get a descriptor + * for one, we add it as an entry guard. Note that the order of bridges + * in this list does not necessarily correspond to the order of bridges + * in the torrc. */ +static smartlist_t *bridge_list = NULL; + +/** Mark every entry of the bridge list to be removed on our next call to + * sweep_bridge_list unless it has first been un-marked. */ +void +mark_bridge_list(void) +{ + if (!bridge_list) + bridge_list = smartlist_new(); + SMARTLIST_FOREACH(bridge_list, bridge_info_t *, b, + b->marked_for_removal = 1); +} + +/** Remove every entry of the bridge list that was marked with + * mark_bridge_list if it has not subsequently been un-marked. */ +void +sweep_bridge_list(void) +{ + if (!bridge_list) + bridge_list = smartlist_new(); + SMARTLIST_FOREACH_BEGIN(bridge_list, bridge_info_t *, b) { + if (b->marked_for_removal) { + SMARTLIST_DEL_CURRENT(bridge_list, b); + bridge_free(b); + } + } SMARTLIST_FOREACH_END(b); +} + +/** Initialize the bridge list to empty, creating it if needed. */ +static void +clear_bridge_list(void) +{ + if (!bridge_list) + bridge_list = smartlist_new(); + SMARTLIST_FOREACH(bridge_list, bridge_info_t *, b, bridge_free(b)); + smartlist_clear(bridge_list); +} + +/** Free the bridge <b>bridge</b>. */ +static void +bridge_free(bridge_info_t *bridge) +{ + if (!bridge) + return; + + tor_free(bridge->transport_name); + if (bridge->socks_args) { + SMARTLIST_FOREACH(bridge->socks_args, char*, s, tor_free(s)); + smartlist_free(bridge->socks_args); + } + + tor_free(bridge); +} + +/** If we have a bridge configured whose digest matches <b>digest</b>, or a + * bridge with no known digest whose address matches any of the + * tor_addr_port_t's in <b>orports</b>, return that bridge. Else return + * NULL. */ +static bridge_info_t * +get_configured_bridge_by_orports_digest(const char *digest, + const smartlist_t *orports) +{ + if (!bridge_list) + return NULL; + SMARTLIST_FOREACH_BEGIN(bridge_list, bridge_info_t *, bridge) + { + if (tor_digest_is_zero(bridge->identity)) { + SMARTLIST_FOREACH_BEGIN(orports, tor_addr_port_t *, ap) + { + if (tor_addr_compare(&bridge->addr, &ap->addr, CMP_EXACT) == 0 && + bridge->port == ap->port) + return bridge; + } + SMARTLIST_FOREACH_END(ap); + } + if (digest && tor_memeq(bridge->identity, digest, DIGEST_LEN)) + return bridge; + } + SMARTLIST_FOREACH_END(bridge); + return NULL; +} + +/** If we have a bridge configured whose digest matches <b>digest</b>, or a + * bridge with no known digest whose address matches <b>addr</b>:<b>port</b>, + * return that bridge. Else return NULL. If <b>digest</b> is NULL, check for + * address/port matches only. */ +static bridge_info_t * +get_configured_bridge_by_addr_port_digest(const tor_addr_t *addr, + uint16_t port, + const char *digest) +{ + if (!bridge_list) + return NULL; + SMARTLIST_FOREACH_BEGIN(bridge_list, bridge_info_t *, bridge) + { + if ((tor_digest_is_zero(bridge->identity) || digest == NULL) && + !tor_addr_compare(&bridge->addr, addr, CMP_EXACT) && + bridge->port == port) + return bridge; + if (digest && tor_memeq(bridge->identity, digest, DIGEST_LEN)) + return bridge; + } + SMARTLIST_FOREACH_END(bridge); + return NULL; +} + +/** If we have a bridge configured whose digest matches <b>digest</b>, or a + * bridge with no known digest whose address matches <b>addr</b>:<b>port</b>, + * return 1. Else return 0. If <b>digest</b> is NULL, check for + * address/port matches only. */ +int +addr_is_a_configured_bridge(const tor_addr_t *addr, + uint16_t port, + const char *digest) +{ + tor_assert(addr); + return get_configured_bridge_by_addr_port_digest(addr, port, digest) ? 1 : 0; +} + +/** If we have a bridge configured whose digest matches + * <b>ei->identity_digest</b>, or a bridge with no known digest whose address + * matches <b>ei->addr</b>:<b>ei->port</b>, return 1. Else return 0. + * If <b>ei->onion_key</b> is NULL, check for address/port matches only. */ +int +extend_info_is_a_configured_bridge(const extend_info_t *ei) +{ + const char *digest = ei->onion_key ? ei->identity_digest : NULL; + return addr_is_a_configured_bridge(&ei->addr, ei->port, digest); +} + +/** Wrapper around get_configured_bridge_by_addr_port_digest() to look + * it up via router descriptor <b>ri</b>. */ +static bridge_info_t * +get_configured_bridge_by_routerinfo(const routerinfo_t *ri) +{ + bridge_info_t *bi = NULL; + smartlist_t *orports = router_get_all_orports(ri); + bi = get_configured_bridge_by_orports_digest(ri->cache_info.identity_digest, + orports); + SMARTLIST_FOREACH(orports, tor_addr_port_t *, p, tor_free(p)); + smartlist_free(orports); + return bi; +} + +/** Return 1 if <b>ri</b> is one of our known bridges, else 0. */ +int +routerinfo_is_a_configured_bridge(const routerinfo_t *ri) +{ + return get_configured_bridge_by_routerinfo(ri) ? 1 : 0; +} + +/** Return 1 if <b>node</b> is one of our configured bridges, else 0. */ +int +node_is_a_configured_bridge(const node_t *node) +{ + int retval = 0; + smartlist_t *orports = node_get_all_orports(node); + retval = get_configured_bridge_by_orports_digest(node->identity, + orports) != NULL; + SMARTLIST_FOREACH(orports, tor_addr_port_t *, p, tor_free(p)); + smartlist_free(orports); + return retval; +} + +/** We made a connection to a router at <b>addr</b>:<b>port</b> + * without knowing its digest. Its digest turned out to be <b>digest</b>. + * If it was a bridge, and we still don't know its digest, record it. + */ +void +learned_router_identity(const tor_addr_t *addr, uint16_t port, + const char *digest) +{ + bridge_info_t *bridge = + get_configured_bridge_by_addr_port_digest(addr, port, digest); + if (bridge && tor_digest_is_zero(bridge->identity)) { + char *transport_info = NULL; + const char *transport_name = + find_transport_name_by_bridge_addrport(addr, port); + if (transport_name) + tor_asprintf(&transport_info, " (with transport '%s')", transport_name); + + memcpy(bridge->identity, digest, DIGEST_LEN); + log_notice(LD_DIR, "Learned fingerprint %s for bridge %s%s.", + hex_str(digest, DIGEST_LEN), fmt_addrport(addr, port), + transport_info ? transport_info : ""); + tor_free(transport_info); + } +} + +/** Return true if <b>bridge</b> has the same identity digest as + * <b>digest</b>. If <b>digest</b> is NULL, it matches + * bridges with unspecified identity digests. */ +static int +bridge_has_digest(const bridge_info_t *bridge, const char *digest) +{ + if (digest) + return tor_memeq(digest, bridge->identity, DIGEST_LEN); + else + return tor_digest_is_zero(bridge->identity); +} + +/** We are about to add a new bridge at <b>addr</b>:<b>port</b>, with optional + * <b>digest</b> and <b>transport_name</b>. Mark for removal any previously + * existing bridge with the same address and port, and warn the user as + * appropriate. + */ +static void +bridge_resolve_conflicts(const tor_addr_t *addr, uint16_t port, + const char *digest, const char *transport_name) +{ + /* Iterate the already-registered bridge list: + + If you find a bridge with the same adress and port, mark it for + removal. It doesn't make sense to have two active bridges with + the same IP:PORT. If the bridge in question has a different + digest or transport than <b>digest</b>/<b>transport_name</b>, + it's probably a misconfiguration and we should warn the user. + */ + SMARTLIST_FOREACH_BEGIN(bridge_list, bridge_info_t *, bridge) { + if (bridge->marked_for_removal) + continue; + + if (tor_addr_eq(&bridge->addr, addr) && (bridge->port == port)) { + + bridge->marked_for_removal = 1; + + if (!bridge_has_digest(bridge, digest) || + strcmp_opt(bridge->transport_name, transport_name)) { + /* warn the user */ + char *bridge_description_new, *bridge_description_old; + tor_asprintf(&bridge_description_new, "%s:%s:%s", + fmt_addrport(addr, port), + digest ? hex_str(digest, DIGEST_LEN) : "", + transport_name ? transport_name : ""); + tor_asprintf(&bridge_description_old, "%s:%s:%s", + fmt_addrport(&bridge->addr, bridge->port), + tor_digest_is_zero(bridge->identity) ? + "" : hex_str(bridge->identity,DIGEST_LEN), + bridge->transport_name ? bridge->transport_name : ""); + + log_warn(LD_GENERAL,"Tried to add bridge '%s', but we found a conflict" + " with the already registered bridge '%s'. We will discard" + " the old bridge and keep '%s'. If this is not what you" + " wanted, please change your configuration file accordingly.", + bridge_description_new, bridge_description_old, + bridge_description_new); + + tor_free(bridge_description_new); + tor_free(bridge_description_old); + } + } + } SMARTLIST_FOREACH_END(bridge); +} + +/** Return True if we have a bridge that uses a transport with name + * <b>transport_name</b>. */ +MOCK_IMPL(int, +transport_is_needed, (const char *transport_name)) +{ + if (!bridge_list) + return 0; + + SMARTLIST_FOREACH_BEGIN(bridge_list, const bridge_info_t *, bridge) { + if (bridge->transport_name && + !strcmp(bridge->transport_name, transport_name)) + return 1; + } SMARTLIST_FOREACH_END(bridge); + + return 0; +} + +/** Register the bridge information in <b>bridge_line</b> to the + * bridge subsystem. Steals reference of <b>bridge_line</b>. */ +void +bridge_add_from_config(bridge_line_t *bridge_line) +{ + bridge_info_t *b; + + { /* Log the bridge we are about to register: */ + log_debug(LD_GENERAL, "Registering bridge at %s (transport: %s) (%s)", + fmt_addrport(&bridge_line->addr, bridge_line->port), + bridge_line->transport_name ? + bridge_line->transport_name : "no transport", + tor_digest_is_zero(bridge_line->digest) ? + "no key listed" : hex_str(bridge_line->digest, DIGEST_LEN)); + + if (bridge_line->socks_args) { /* print socks arguments */ + int i = 0; + + tor_assert(smartlist_len(bridge_line->socks_args) > 0); + + log_debug(LD_GENERAL, "Bridge uses %d SOCKS arguments:", + smartlist_len(bridge_line->socks_args)); + SMARTLIST_FOREACH(bridge_line->socks_args, const char *, arg, + log_debug(LD_CONFIG, "%d: %s", ++i, arg)); + } + } + + bridge_resolve_conflicts(&bridge_line->addr, + bridge_line->port, + bridge_line->digest, + bridge_line->transport_name); + + b = tor_malloc_zero(sizeof(bridge_info_t)); + tor_addr_copy(&b->addr, &bridge_line->addr); + b->port = bridge_line->port; + memcpy(b->identity, bridge_line->digest, DIGEST_LEN); + if (bridge_line->transport_name) + b->transport_name = bridge_line->transport_name; + b->fetch_status.schedule = DL_SCHED_BRIDGE; + b->fetch_status.backoff = DL_SCHED_RANDOM_EXPONENTIAL; + b->socks_args = bridge_line->socks_args; + if (!bridge_list) + bridge_list = smartlist_new(); + + tor_free(bridge_line); /* Deallocate bridge_line now. */ + + smartlist_add(bridge_list, b); +} + +/** Return true iff <b>routerset</b> contains the bridge <b>bridge</b>. */ +static int +routerset_contains_bridge(const routerset_t *routerset, + const bridge_info_t *bridge) +{ + int result; + extend_info_t *extinfo; + tor_assert(bridge); + if (!routerset) + return 0; + + extinfo = extend_info_new( + NULL, bridge->identity, NULL, NULL, &bridge->addr, bridge->port); + result = routerset_contains_extendinfo(routerset, extinfo); + extend_info_free(extinfo); + return result; +} + +/** If <b>digest</b> is one of our known bridges, return it. */ +static bridge_info_t * +find_bridge_by_digest(const char *digest) +{ + SMARTLIST_FOREACH(bridge_list, bridge_info_t *, bridge, + { + if (tor_memeq(bridge->identity, digest, DIGEST_LEN)) + return bridge; + }); + return NULL; +} + +/** Given the <b>addr</b> and <b>port</b> of a bridge, if that bridge + * supports a pluggable transport, return its name. Otherwise, return + * NULL. */ +const char * +find_transport_name_by_bridge_addrport(const tor_addr_t *addr, uint16_t port) +{ + if (!bridge_list) + return NULL; + + SMARTLIST_FOREACH_BEGIN(bridge_list, const bridge_info_t *, bridge) { + if (tor_addr_eq(&bridge->addr, addr) && + (bridge->port == port)) + return bridge->transport_name; + } SMARTLIST_FOREACH_END(bridge); + + return NULL; +} + +/** If <b>addr</b> and <b>port</b> match the address and port of a + * bridge of ours that uses pluggable transports, place its transport + * in <b>transport</b>. + * + * Return 0 on success (found a transport, or found a bridge with no + * transport, or found no bridge); return -1 if we should be using a + * transport, but the transport could not be found. + */ +int +get_transport_by_bridge_addrport(const tor_addr_t *addr, uint16_t port, + const transport_t **transport) +{ + *transport = NULL; + if (!bridge_list) + return 0; + + SMARTLIST_FOREACH_BEGIN(bridge_list, const bridge_info_t *, bridge) { + if (tor_addr_eq(&bridge->addr, addr) && + (bridge->port == port)) { /* bridge matched */ + if (bridge->transport_name) { /* it also uses pluggable transports */ + *transport = transport_get_by_name(bridge->transport_name); + if (*transport == NULL) { /* it uses pluggable transports, but + the transport could not be found! */ + return -1; + } + return 0; + } else { /* bridge matched, but it doesn't use transports. */ + break; + } + } + } SMARTLIST_FOREACH_END(bridge); + + *transport = NULL; + return 0; +} + +/** Return a smartlist containing all the SOCKS arguments that we + * should pass to the SOCKS proxy. */ +const smartlist_t * +get_socks_args_by_bridge_addrport(const tor_addr_t *addr, uint16_t port) +{ + bridge_info_t *bridge = get_configured_bridge_by_addr_port_digest(addr, + port, + NULL); + return bridge ? bridge->socks_args : NULL; +} + +/** We need to ask <b>bridge</b> for its server descriptor. */ +static void +launch_direct_bridge_descriptor_fetch(bridge_info_t *bridge) +{ + const or_options_t *options = get_options(); + + if (connection_get_by_type_addr_port_purpose( + CONN_TYPE_DIR, &bridge->addr, bridge->port, + DIR_PURPOSE_FETCH_SERVERDESC)) + return; /* it's already on the way */ + + if (routerset_contains_bridge(options->ExcludeNodes, bridge)) { + download_status_mark_impossible(&bridge->fetch_status); + log_warn(LD_APP, "Not using bridge at %s: it is in ExcludeNodes.", + safe_str_client(fmt_and_decorate_addr(&bridge->addr))); + return; + } + + /* Until we get a descriptor for the bridge, we only know one address for + * it. */ + if (!fascist_firewall_allows_address_addr(&bridge->addr, bridge->port, + FIREWALL_OR_CONNECTION, 0, 0)) { + log_notice(LD_CONFIG, "Tried to fetch a descriptor directly from a " + "bridge, but that bridge is not reachable through our " + "firewall."); + return; + } + + directory_initiate_command(&bridge->addr, bridge->port, + NULL, 0, /*no dirport*/ + bridge->identity, + DIR_PURPOSE_FETCH_SERVERDESC, + ROUTER_PURPOSE_BRIDGE, + DIRIND_ONEHOP, "authority.z", NULL, 0, 0); +} + +/** Fetching the bridge descriptor from the bridge authority returned a + * "not found". Fall back to trying a direct fetch. */ +void +retry_bridge_descriptor_fetch_directly(const char *digest) +{ + bridge_info_t *bridge = find_bridge_by_digest(digest); + if (!bridge) + return; /* not found? oh well. */ + + launch_direct_bridge_descriptor_fetch(bridge); +} + +/** For each bridge in our list for which we don't currently have a + * descriptor, fetch a new copy of its descriptor -- either directly + * from the bridge or via a bridge authority. */ +void +fetch_bridge_descriptors(const or_options_t *options, time_t now) +{ + int num_bridge_auths = get_n_authorities(BRIDGE_DIRINFO); + int ask_bridge_directly; + int can_use_bridge_authority; + + if (!bridge_list) + return; + + /* If we still have unconfigured managed proxies, don't go and + connect to a bridge. */ + if (pt_proxies_configuration_pending()) + return; + + SMARTLIST_FOREACH_BEGIN(bridge_list, bridge_info_t *, bridge) + { + if (!download_status_is_ready(&bridge->fetch_status, now, + IMPOSSIBLE_TO_DOWNLOAD)) + continue; /* don't bother, no need to retry yet */ + if (routerset_contains_bridge(options->ExcludeNodes, bridge)) { + download_status_mark_impossible(&bridge->fetch_status); + log_warn(LD_APP, "Not using bridge at %s: it is in ExcludeNodes.", + safe_str_client(fmt_and_decorate_addr(&bridge->addr))); + continue; + } + + /* schedule another fetch as if this one will fail, in case it does */ + download_status_failed(&bridge->fetch_status, 0); + + can_use_bridge_authority = !tor_digest_is_zero(bridge->identity) && + num_bridge_auths; + ask_bridge_directly = !can_use_bridge_authority || + !options->UpdateBridgesFromAuthority; + log_debug(LD_DIR, "ask_bridge_directly=%d (%d, %d, %d)", + ask_bridge_directly, tor_digest_is_zero(bridge->identity), + !options->UpdateBridgesFromAuthority, !num_bridge_auths); + + if (ask_bridge_directly && + !fascist_firewall_allows_address_addr(&bridge->addr, bridge->port, + FIREWALL_OR_CONNECTION, 0, + 0)) { + log_notice(LD_DIR, "Bridge at '%s' isn't reachable by our " + "firewall policy. %s.", + fmt_addrport(&bridge->addr, bridge->port), + can_use_bridge_authority ? + "Asking bridge authority instead" : "Skipping"); + if (can_use_bridge_authority) + ask_bridge_directly = 0; + else + continue; + } + + if (ask_bridge_directly) { + /* we need to ask the bridge itself for its descriptor. */ + launch_direct_bridge_descriptor_fetch(bridge); + } else { + /* We have a digest and we want to ask an authority. We could + * combine all the requests into one, but that may give more + * hints to the bridge authority than we want to give. */ + char resource[10 + HEX_DIGEST_LEN]; + memcpy(resource, "fp/", 3); + base16_encode(resource+3, HEX_DIGEST_LEN+1, + bridge->identity, DIGEST_LEN); + memcpy(resource+3+HEX_DIGEST_LEN, ".z", 3); + log_info(LD_DIR, "Fetching bridge info '%s' from bridge authority.", + resource); + directory_get_from_dirserver(DIR_PURPOSE_FETCH_SERVERDESC, + ROUTER_PURPOSE_BRIDGE, resource, 0, DL_WANT_AUTHORITY); + } + } + SMARTLIST_FOREACH_END(bridge); +} + +/** If our <b>bridge</b> is configured to be a different address than + * the bridge gives in <b>node</b>, rewrite the routerinfo + * we received to use the address we meant to use. Now we handle + * multihomed bridges better. + */ +static void +rewrite_node_address_for_bridge(const bridge_info_t *bridge, node_t *node) +{ + /* XXXX move this function. */ + /* XXXX overridden addresses should really live in the node_t, so that the + * routerinfo_t and the microdesc_t can be immutable. But we can only + * do that safely if we know that no function that connects to an OR + * does so through an address from any source other than node_get_addr(). + */ + tor_addr_t addr; + const or_options_t *options = get_options(); + + if (node->ri) { + routerinfo_t *ri = node->ri; + tor_addr_from_ipv4h(&addr, ri->addr); + + if ((!tor_addr_compare(&bridge->addr, &addr, CMP_EXACT) && + bridge->port == ri->or_port) || + (!tor_addr_compare(&bridge->addr, &ri->ipv6_addr, CMP_EXACT) && + bridge->port == ri->ipv6_orport)) { + /* they match, so no need to do anything */ + } else { + if (tor_addr_family(&bridge->addr) == AF_INET) { + ri->addr = tor_addr_to_ipv4h(&bridge->addr); + ri->or_port = bridge->port; + log_info(LD_DIR, + "Adjusted bridge routerinfo for '%s' to match configured " + "address %s:%d.", + ri->nickname, fmt_addr32(ri->addr), ri->or_port); + } else if (tor_addr_family(&bridge->addr) == AF_INET6) { + tor_addr_copy(&ri->ipv6_addr, &bridge->addr); + ri->ipv6_orport = bridge->port; + log_info(LD_DIR, + "Adjusted bridge routerinfo for '%s' to match configured " + "address %s.", + ri->nickname, fmt_addrport(&ri->ipv6_addr, ri->ipv6_orport)); + } else { + log_err(LD_BUG, "Address family not supported: %d.", + tor_addr_family(&bridge->addr)); + return; + } + } + + if (options->ClientPreferIPv6ORPort == -1) { + /* Mark which address to use based on which bridge_t we got. */ + node->ipv6_preferred = (tor_addr_family(&bridge->addr) == AF_INET6 && + !tor_addr_is_null(&node->ri->ipv6_addr)); + } else { + /* Mark which address to use based on user preference */ + node->ipv6_preferred = (fascist_firewall_prefer_ipv6_orport(options) && + !tor_addr_is_null(&node->ri->ipv6_addr)); + } + + /* XXXipv6 we lack support for falling back to another address for + the same relay, warn the user */ + if (!tor_addr_is_null(&ri->ipv6_addr)) { + tor_addr_port_t ap; + node_get_pref_orport(node, &ap); + log_notice(LD_CONFIG, + "Bridge '%s' has both an IPv4 and an IPv6 address. " + "Will prefer using its %s address (%s) based on %s.", + ri->nickname, + node->ipv6_preferred ? "IPv6" : "IPv4", + fmt_addrport(&ap.addr, ap.port), + options->ClientPreferIPv6ORPort == -1 ? + "the configured Bridge address" : + "ClientPreferIPv6ORPort"); + } + } + if (node->rs) { + routerstatus_t *rs = node->rs; + tor_addr_from_ipv4h(&addr, rs->addr); + + if (!tor_addr_compare(&bridge->addr, &addr, CMP_EXACT) && + bridge->port == rs->or_port) { + /* they match, so no need to do anything */ + } else { + rs->addr = tor_addr_to_ipv4h(&bridge->addr); + rs->or_port = bridge->port; + log_info(LD_DIR, + "Adjusted bridge routerstatus for '%s' to match " + "configured address %s.", + rs->nickname, fmt_addrport(&bridge->addr, rs->or_port)); + } + } +} + +/** We just learned a descriptor for a bridge. See if that + * digest is in our entry guard list, and add it if not. */ +void +learned_bridge_descriptor(routerinfo_t *ri, int from_cache) +{ + tor_assert(ri); + tor_assert(ri->purpose == ROUTER_PURPOSE_BRIDGE); + if (get_options()->UseBridges) { + int first = num_bridges_usable() <= 1; + bridge_info_t *bridge = get_configured_bridge_by_routerinfo(ri); + time_t now = time(NULL); + router_set_status(ri->cache_info.identity_digest, 1); + + if (bridge) { /* if we actually want to use this one */ + node_t *node; + /* it's here; schedule its re-fetch for a long time from now. */ + if (!from_cache) + download_status_reset(&bridge->fetch_status); + + node = node_get_mutable_by_id(ri->cache_info.identity_digest); + tor_assert(node); + rewrite_node_address_for_bridge(bridge, node); + if (tor_digest_is_zero(bridge->identity)) { + memcpy(bridge->identity,ri->cache_info.identity_digest, DIGEST_LEN); + log_notice(LD_DIR, "Learned identity %s for bridge at %s:%d", + hex_str(bridge->identity, DIGEST_LEN), + fmt_and_decorate_addr(&bridge->addr), + (int) bridge->port); + } + add_an_entry_guard(get_guard_selection_info(), node, 1, 1, 0, 0); + + log_notice(LD_DIR, "new bridge descriptor '%s' (%s): %s", ri->nickname, + from_cache ? "cached" : "fresh", router_describe(ri)); + /* set entry->made_contact so if it goes down we don't drop it from + * our entry node list */ + entry_guard_register_connect_status(ri->cache_info.identity_digest, + 1, 0, now); + if (first) { + routerlist_retry_directory_downloads(now); + } + } + } +} + +/** Return the number of bridges that have descriptors that + * are marked with purpose 'bridge' and are running. + * + * We use this function to decide if we're ready to start building + * circuits through our bridges, or if we need to wait until the + * directory "server/authority" requests finish. */ +int +any_bridge_descriptors_known(void) +{ + tor_assert(get_options()->UseBridges); + return choose_random_entry(NULL) != NULL; +} + +/** Return the number of bridges that have descriptors that are marked with + * purpose 'bridge' and are running. + */ +static int +num_bridges_usable(void) +{ + int n_options = 0; + tor_assert(get_options()->UseBridges); + (void) choose_random_entry_impl(get_guard_selection_info(), + NULL, 0, 0, &n_options); + return n_options; +} + +/** Return a smartlist containing all bridge identity digests */ +MOCK_IMPL(smartlist_t *, +list_bridge_identities, (void)) +{ + smartlist_t *result = NULL; + char *digest_tmp; + + if (get_options()->UseBridges && bridge_list) { + result = smartlist_new(); + + SMARTLIST_FOREACH_BEGIN(bridge_list, bridge_info_t *, b) { + digest_tmp = tor_malloc(DIGEST_LEN); + memcpy(digest_tmp, b->identity, DIGEST_LEN); + smartlist_add(result, digest_tmp); + } SMARTLIST_FOREACH_END(b); + } + + return result; +} + +/** Get the download status for a bridge descriptor given its identity */ +MOCK_IMPL(download_status_t *, +get_bridge_dl_status_by_id, (const char *digest)) +{ + download_status_t *dl = NULL; + + if (digest && get_options()->UseBridges && bridge_list) { + SMARTLIST_FOREACH_BEGIN(bridge_list, bridge_info_t *, b) { + if (tor_memeq(digest, b->identity, DIGEST_LEN)) { + dl = &(b->fetch_status); + break; + } + } SMARTLIST_FOREACH_END(b); + } + + return dl; +} + +/** Release all storage held in bridges.c */ +void +bridges_free_all(void) +{ + clear_bridge_list(); + smartlist_free(bridge_list); + bridge_list = NULL; +} + diff --git a/src/or/bridges.h b/src/or/bridges.h new file mode 100644 index 0000000..738b1a6 --- /dev/null +++ b/src/or/bridges.h @@ -0,0 +1,54 @@ +/* Copyright (c) 2001 Matej Pfajfar. + * Copyright (c) 2001-2004, Roger Dingledine. + * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. + * Copyright (c) 2007-2016, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +/** + * \file bridges.h + * \brief Header file for circuitbuild.c. + **/ + +#ifndef TOR_BRIDGES_H +#define TOR_BRIDGES_H + +struct bridge_line_t; + +void mark_bridge_list(void); +void sweep_bridge_list(void); + +int addr_is_a_configured_bridge(const tor_addr_t *addr, uint16_t port, + const char *digest); +int extend_info_is_a_configured_bridge(const extend_info_t *ei); +int routerinfo_is_a_configured_bridge(const routerinfo_t *ri); +int node_is_a_configured_bridge(const node_t *node); +void learned_router_identity(const tor_addr_t *addr, uint16_t port, + const char *digest); + +void bridge_add_from_config(struct bridge_line_t *bridge_line); +void retry_bridge_descriptor_fetch_directly(const char *digest); +void fetch_bridge_descriptors(const or_options_t *options, time_t now); +void learned_bridge_descriptor(routerinfo_t *ri, int from_cache); +int any_bridge_descriptors_known(void); +const smartlist_t *get_socks_args_by_bridge_addrport(const tor_addr_t *addr, + uint16_t port); + +int any_bridges_dont_support_microdescriptors(void); + +const char *find_transport_name_by_bridge_addrport(const tor_addr_t *addr, + uint16_t port); +struct transport_t; +int get_transport_by_bridge_addrport(const tor_addr_t *addr, uint16_t port, + const struct transport_t **transport); + +MOCK_DECL(int, transport_is_needed, (const char *transport_name)); +int validate_pluggable_transports_config(void); + +MOCK_DECL(smartlist_t *, list_bridge_identities, (void)); +MOCK_DECL(download_status_t *, get_bridge_dl_status_by_id, + (const char *digest)); + +void bridges_free_all(void); + +#endif + diff --git a/src/or/circuitbuild.c b/src/or/circuitbuild.c index 2998f5c..b482e78 100644 --- a/src/or/circuitbuild.c +++ b/src/or/circuitbuild.c @@ -28,6 +28,7 @@ #define CIRCUITBUILD_PRIVATE
#include "or.h" +#include "bridges.h" #include "channel.h" #include "circpathbias.h" #define CIRCUITBUILD_PRIVATE diff --git a/src/or/circuituse.c b/src/or/circuituse.c index ba7b75f..2f972d1 100644 --- a/src/or/circuituse.c +++ b/src/or/circuituse.c @@ -29,6 +29,7 @@
#include "or.h" #include "addressmap.h" +#include "bridges.h" #include "channel.h" #include "circpathbias.h" #include "circuitbuild.h" diff --git a/src/or/config.c b/src/or/config.c index 9553822..79a5847 100644 --- a/src/or/config.c +++ b/src/or/config.c @@ -60,6 +60,7 @@
#define CONFIG_PRIVATE #include "or.h" +#include "bridges.h" #include "compat.h" #include "addressmap.h" #include "channel.h" diff --git a/src/or/connection.c b/src/or/connection.c index 2e3df34..2964c30 100644 --- a/src/or/connection.c +++ b/src/or/connection.c @@ -56,6 +56,7 @@
#define CONNECTION_PRIVATE #include "or.h" +#include "bridges.h" #include "buffers.h" /* * Define this so we get channel internal functions, since we're implementing diff --git a/src/or/connection_or.c b/src/or/connection_or.c index eb67f06..ecc5a45 100644 --- a/src/or/connection_or.c +++ b/src/or/connection_or.c @@ -21,6 +21,7 @@ * This module also implements the client side of the v3 Tor link handshake, **/ #include "or.h" +#include "bridges.h" #include "buffers.h" /* * Define this so we get channel internal functions, since we're implementing diff --git a/src/or/control.c b/src/or/control.c index f0cb435..1d7ec1b 100644 --- a/src/or/control.c +++ b/src/or/control.c @@ -36,6 +36,7 @@
#include "or.h" #include "addressmap.h" +#include "bridges.h" #include "buffers.h" #include "channel.h" #include "channeltls.h" diff --git a/src/or/directory.c b/src/or/directory.c index 65ddd7d..efa5a31 100644 --- a/src/or/directory.c +++ b/src/or/directory.c @@ -7,6 +7,7 @@
#include "or.h" #include "backtrace.h" +#include "bridges.h" #include "buffers.h" #include "circuitbuild.h" #include "config.h" diff --git a/src/or/entrynodes.c b/src/or/entrynodes.c index 9af7140..886e653 100644 --- a/src/or/entrynodes.c +++ b/src/or/entrynodes.c @@ -15,6 +15,7 @@ #define ENTRYNODES_PRIVATE
#include "or.h" +#include "bridges.h" #include "circpathbias.h" #include "circuitbuild.h" #include "circuitstats.h" @@ -37,32 +38,6 @@ #include "transports.h" #include "statefile.h"
-/** Information about a configured bridge. Currently this just matches the - * ones in the torrc file, but one day we may be able to learn about new - * bridges on our own, and remember them in the state file. */ -typedef struct { - /** Address of the bridge. */ - tor_addr_t addr; - /** TLS port for the bridge. */ - uint16_t port; - /** Boolean: We are re-parsing our bridge list, and we are going to remove - * this one if we don't find it in the list of configured bridges. */ - unsigned marked_for_removal : 1; - /** Expected identity digest, or all zero bytes if we don't know what the - * digest should be. */ - char identity[DIGEST_LEN]; - - /** Name of pluggable transport protocol taken from its config line. */ - char *transport_name; - - /** When should we next try to fetch a descriptor for this bridge? */ - download_status_t fetch_status; - - /** A smartlist of k=v values to be passed to the SOCKS proxy, if - transports are used for this bridge. */ - smartlist_t *socks_args; -} bridge_info_t; - /** All the context for guard selection on a particular client */
struct guard_selection_s { @@ -99,14 +74,12 @@ struct guard_selection_s { static smartlist_t *guard_contexts = NULL; static guard_selection_t *curr_guard_context = NULL;
-static void bridge_free(bridge_info_t *bridge); static const node_t *choose_random_entry_impl(guard_selection_t *gs, cpath_build_state_t *state, int for_directory, dirinfo_type_t dirtype, int *n_options_out); static guard_selection_t * guard_selection_new(void); -static int num_bridges_usable(void);
/* Default number of entry guards in the case where the NumEntryGuards * consensus parameter is not set */ @@ -2282,330 +2255,6 @@ guard_get_guardfraction_bandwidth(guardfraction_bandwidth_t *guardfraction_bw, guardfraction_bw->non_guard_bw = orig_bandwidth - (int) guard_bw; }
-/** A list of configured bridges. Whenever we actually get a descriptor - * for one, we add it as an entry guard. Note that the order of bridges - * in this list does not necessarily correspond to the order of bridges - * in the torrc. */ -static smartlist_t *bridge_list = NULL; - -/** Mark every entry of the bridge list to be removed on our next call to - * sweep_bridge_list unless it has first been un-marked. */ -void -mark_bridge_list(void) -{ - if (!bridge_list) - bridge_list = smartlist_new(); - SMARTLIST_FOREACH(bridge_list, bridge_info_t *, b, - b->marked_for_removal = 1); -} - -/** Remove every entry of the bridge list that was marked with - * mark_bridge_list if it has not subsequently been un-marked. */ -void -sweep_bridge_list(void) -{ - if (!bridge_list) - bridge_list = smartlist_new(); - SMARTLIST_FOREACH_BEGIN(bridge_list, bridge_info_t *, b) { - if (b->marked_for_removal) { - SMARTLIST_DEL_CURRENT(bridge_list, b); - bridge_free(b); - } - } SMARTLIST_FOREACH_END(b); -} - -/** Initialize the bridge list to empty, creating it if needed. */ -static void -clear_bridge_list(void) -{ - if (!bridge_list) - bridge_list = smartlist_new(); - SMARTLIST_FOREACH(bridge_list, bridge_info_t *, b, bridge_free(b)); - smartlist_clear(bridge_list); -} - -/** Free the bridge <b>bridge</b>. */ -static void -bridge_free(bridge_info_t *bridge) -{ - if (!bridge) - return; - - tor_free(bridge->transport_name); - if (bridge->socks_args) { - SMARTLIST_FOREACH(bridge->socks_args, char*, s, tor_free(s)); - smartlist_free(bridge->socks_args); - } - - tor_free(bridge); -} - -/** If we have a bridge configured whose digest matches <b>digest</b>, or a - * bridge with no known digest whose address matches any of the - * tor_addr_port_t's in <b>orports</b>, return that bridge. Else return - * NULL. */ -static bridge_info_t * -get_configured_bridge_by_orports_digest(const char *digest, - const smartlist_t *orports) -{ - if (!bridge_list) - return NULL; - SMARTLIST_FOREACH_BEGIN(bridge_list, bridge_info_t *, bridge) - { - if (tor_digest_is_zero(bridge->identity)) { - SMARTLIST_FOREACH_BEGIN(orports, tor_addr_port_t *, ap) - { - if (tor_addr_compare(&bridge->addr, &ap->addr, CMP_EXACT) == 0 && - bridge->port == ap->port) - return bridge; - } - SMARTLIST_FOREACH_END(ap); - } - if (digest && tor_memeq(bridge->identity, digest, DIGEST_LEN)) - return bridge; - } - SMARTLIST_FOREACH_END(bridge); - return NULL; -} - -/** If we have a bridge configured whose digest matches <b>digest</b>, or a - * bridge with no known digest whose address matches <b>addr</b>:<b>port</b>, - * return that bridge. Else return NULL. If <b>digest</b> is NULL, check for - * address/port matches only. */ -static bridge_info_t * -get_configured_bridge_by_addr_port_digest(const tor_addr_t *addr, - uint16_t port, - const char *digest) -{ - if (!bridge_list) - return NULL; - SMARTLIST_FOREACH_BEGIN(bridge_list, bridge_info_t *, bridge) - { - if ((tor_digest_is_zero(bridge->identity) || digest == NULL) && - !tor_addr_compare(&bridge->addr, addr, CMP_EXACT) && - bridge->port == port) - return bridge; - if (digest && tor_memeq(bridge->identity, digest, DIGEST_LEN)) - return bridge; - } - SMARTLIST_FOREACH_END(bridge); - return NULL; -} - -/** If we have a bridge configured whose digest matches <b>digest</b>, or a - * bridge with no known digest whose address matches <b>addr</b>:<b>port</b>, - * return 1. Else return 0. If <b>digest</b> is NULL, check for - * address/port matches only. */ -int -addr_is_a_configured_bridge(const tor_addr_t *addr, - uint16_t port, - const char *digest) -{ - tor_assert(addr); - return get_configured_bridge_by_addr_port_digest(addr, port, digest) ? 1 : 0; -} - -/** If we have a bridge configured whose digest matches - * <b>ei->identity_digest</b>, or a bridge with no known digest whose address - * matches <b>ei->addr</b>:<b>ei->port</b>, return 1. Else return 0. - * If <b>ei->onion_key</b> is NULL, check for address/port matches only. */ -int -extend_info_is_a_configured_bridge(const extend_info_t *ei) -{ - const char *digest = ei->onion_key ? ei->identity_digest : NULL; - return addr_is_a_configured_bridge(&ei->addr, ei->port, digest); -} - -/** Wrapper around get_configured_bridge_by_addr_port_digest() to look - * it up via router descriptor <b>ri</b>. */ -static bridge_info_t * -get_configured_bridge_by_routerinfo(const routerinfo_t *ri) -{ - bridge_info_t *bi = NULL; - smartlist_t *orports = router_get_all_orports(ri); - bi = get_configured_bridge_by_orports_digest(ri->cache_info.identity_digest, - orports); - SMARTLIST_FOREACH(orports, tor_addr_port_t *, p, tor_free(p)); - smartlist_free(orports); - return bi; -} - -/** Return 1 if <b>ri</b> is one of our known bridges, else 0. */ -int -routerinfo_is_a_configured_bridge(const routerinfo_t *ri) -{ - return get_configured_bridge_by_routerinfo(ri) ? 1 : 0; -} - -/** Return 1 if <b>node</b> is one of our configured bridges, else 0. */ -int -node_is_a_configured_bridge(const node_t *node) -{ - int retval = 0; - smartlist_t *orports = node_get_all_orports(node); - retval = get_configured_bridge_by_orports_digest(node->identity, - orports) != NULL; - SMARTLIST_FOREACH(orports, tor_addr_port_t *, p, tor_free(p)); - smartlist_free(orports); - return retval; -} - -/** We made a connection to a router at <b>addr</b>:<b>port</b> - * without knowing its digest. Its digest turned out to be <b>digest</b>. - * If it was a bridge, and we still don't know its digest, record it. - */ -void -learned_router_identity(const tor_addr_t *addr, uint16_t port, - const char *digest) -{ - bridge_info_t *bridge = - get_configured_bridge_by_addr_port_digest(addr, port, digest); - if (bridge && tor_digest_is_zero(bridge->identity)) { - char *transport_info = NULL; - const char *transport_name = - find_transport_name_by_bridge_addrport(addr, port); - if (transport_name) - tor_asprintf(&transport_info, " (with transport '%s')", transport_name); - - memcpy(bridge->identity, digest, DIGEST_LEN); - log_notice(LD_DIR, "Learned fingerprint %s for bridge %s%s.", - hex_str(digest, DIGEST_LEN), fmt_addrport(addr, port), - transport_info ? transport_info : ""); - tor_free(transport_info); - } -} - -/** Return true if <b>bridge</b> has the same identity digest as - * <b>digest</b>. If <b>digest</b> is NULL, it matches - * bridges with unspecified identity digests. */ -static int -bridge_has_digest(const bridge_info_t *bridge, const char *digest) -{ - if (digest) - return tor_memeq(digest, bridge->identity, DIGEST_LEN); - else - return tor_digest_is_zero(bridge->identity); -} - -/** We are about to add a new bridge at <b>addr</b>:<b>port</b>, with optional - * <b>digest</b> and <b>transport_name</b>. Mark for removal any previously - * existing bridge with the same address and port, and warn the user as - * appropriate. - */ -static void -bridge_resolve_conflicts(const tor_addr_t *addr, uint16_t port, - const char *digest, const char *transport_name) -{ - /* Iterate the already-registered bridge list: - - If you find a bridge with the same adress and port, mark it for - removal. It doesn't make sense to have two active bridges with - the same IP:PORT. If the bridge in question has a different - digest or transport than <b>digest</b>/<b>transport_name</b>, - it's probably a misconfiguration and we should warn the user. - */ - SMARTLIST_FOREACH_BEGIN(bridge_list, bridge_info_t *, bridge) { - if (bridge->marked_for_removal) - continue; - - if (tor_addr_eq(&bridge->addr, addr) && (bridge->port == port)) { - - bridge->marked_for_removal = 1; - - if (!bridge_has_digest(bridge, digest) || - strcmp_opt(bridge->transport_name, transport_name)) { - /* warn the user */ - char *bridge_description_new, *bridge_description_old; - tor_asprintf(&bridge_description_new, "%s:%s:%s", - fmt_addrport(addr, port), - digest ? hex_str(digest, DIGEST_LEN) : "", - transport_name ? transport_name : ""); - tor_asprintf(&bridge_description_old, "%s:%s:%s", - fmt_addrport(&bridge->addr, bridge->port), - tor_digest_is_zero(bridge->identity) ? - "" : hex_str(bridge->identity,DIGEST_LEN), - bridge->transport_name ? bridge->transport_name : ""); - - log_warn(LD_GENERAL,"Tried to add bridge '%s', but we found a conflict" - " with the already registered bridge '%s'. We will discard" - " the old bridge and keep '%s'. If this is not what you" - " wanted, please change your configuration file accordingly.", - bridge_description_new, bridge_description_old, - bridge_description_new); - - tor_free(bridge_description_new); - tor_free(bridge_description_old); - } - } - } SMARTLIST_FOREACH_END(bridge); -} - -/** Return True if we have a bridge that uses a transport with name - * <b>transport_name</b>. */ -MOCK_IMPL(int, -transport_is_needed, (const char *transport_name)) -{ - if (!bridge_list) - return 0; - - SMARTLIST_FOREACH_BEGIN(bridge_list, const bridge_info_t *, bridge) { - if (bridge->transport_name && - !strcmp(bridge->transport_name, transport_name)) - return 1; - } SMARTLIST_FOREACH_END(bridge); - - return 0; -} - -/** Register the bridge information in <b>bridge_line</b> to the - * bridge subsystem. Steals reference of <b>bridge_line</b>. */ -void -bridge_add_from_config(bridge_line_t *bridge_line) -{ - bridge_info_t *b; - - { /* Log the bridge we are about to register: */ - log_debug(LD_GENERAL, "Registering bridge at %s (transport: %s) (%s)", - fmt_addrport(&bridge_line->addr, bridge_line->port), - bridge_line->transport_name ? - bridge_line->transport_name : "no transport", - tor_digest_is_zero(bridge_line->digest) ? - "no key listed" : hex_str(bridge_line->digest, DIGEST_LEN)); - - if (bridge_line->socks_args) { /* print socks arguments */ - int i = 0; - - tor_assert(smartlist_len(bridge_line->socks_args) > 0); - - log_debug(LD_GENERAL, "Bridge uses %d SOCKS arguments:", - smartlist_len(bridge_line->socks_args)); - SMARTLIST_FOREACH(bridge_line->socks_args, const char *, arg, - log_debug(LD_CONFIG, "%d: %s", ++i, arg)); - } - } - - bridge_resolve_conflicts(&bridge_line->addr, - bridge_line->port, - bridge_line->digest, - bridge_line->transport_name); - - b = tor_malloc_zero(sizeof(bridge_info_t)); - tor_addr_copy(&b->addr, &bridge_line->addr); - b->port = bridge_line->port; - memcpy(b->identity, bridge_line->digest, DIGEST_LEN); - if (bridge_line->transport_name) - b->transport_name = bridge_line->transport_name; - b->fetch_status.schedule = DL_SCHED_BRIDGE; - b->fetch_status.backoff = DL_SCHED_RANDOM_EXPONENTIAL; - b->socks_args = bridge_line->socks_args; - if (!bridge_list) - bridge_list = smartlist_new(); - - tor_free(bridge_line); /* Deallocate bridge_line now. */ - - smartlist_add(bridge_list, b); -} - /** Returns true iff the node is used as a guard in the specified guard * context */ int @@ -2642,426 +2291,6 @@ is_node_used_as_guard, (const node_t *node)) get_guard_selection_info(), node); }
-/** Return true iff <b>routerset</b> contains the bridge <b>bridge</b>. */ -static int -routerset_contains_bridge(const routerset_t *routerset, - const bridge_info_t *bridge) -{ - int result; - extend_info_t *extinfo; - tor_assert(bridge); - if (!routerset) - return 0; - - extinfo = extend_info_new( - NULL, bridge->identity, NULL, NULL, &bridge->addr, bridge->port); - result = routerset_contains_extendinfo(routerset, extinfo); - extend_info_free(extinfo); - return result; -} - -/** If <b>digest</b> is one of our known bridges, return it. */ -static bridge_info_t * -find_bridge_by_digest(const char *digest) -{ - SMARTLIST_FOREACH(bridge_list, bridge_info_t *, bridge, - { - if (tor_memeq(bridge->identity, digest, DIGEST_LEN)) - return bridge; - }); - return NULL; -} - -/** Given the <b>addr</b> and <b>port</b> of a bridge, if that bridge - * supports a pluggable transport, return its name. Otherwise, return - * NULL. */ -const char * -find_transport_name_by_bridge_addrport(const tor_addr_t *addr, uint16_t port) -{ - if (!bridge_list) - return NULL; - - SMARTLIST_FOREACH_BEGIN(bridge_list, const bridge_info_t *, bridge) { - if (tor_addr_eq(&bridge->addr, addr) && - (bridge->port == port)) - return bridge->transport_name; - } SMARTLIST_FOREACH_END(bridge); - - return NULL; -} - -/** If <b>addr</b> and <b>port</b> match the address and port of a - * bridge of ours that uses pluggable transports, place its transport - * in <b>transport</b>. - * - * Return 0 on success (found a transport, or found a bridge with no - * transport, or found no bridge); return -1 if we should be using a - * transport, but the transport could not be found. - */ -int -get_transport_by_bridge_addrport(const tor_addr_t *addr, uint16_t port, - const transport_t **transport) -{ - *transport = NULL; - if (!bridge_list) - return 0; - - SMARTLIST_FOREACH_BEGIN(bridge_list, const bridge_info_t *, bridge) { - if (tor_addr_eq(&bridge->addr, addr) && - (bridge->port == port)) { /* bridge matched */ - if (bridge->transport_name) { /* it also uses pluggable transports */ - *transport = transport_get_by_name(bridge->transport_name); - if (*transport == NULL) { /* it uses pluggable transports, but - the transport could not be found! */ - return -1; - } - return 0; - } else { /* bridge matched, but it doesn't use transports. */ - break; - } - } - } SMARTLIST_FOREACH_END(bridge); - - *transport = NULL; - return 0; -} - -/** Return a smartlist containing all the SOCKS arguments that we - * should pass to the SOCKS proxy. */ -const smartlist_t * -get_socks_args_by_bridge_addrport(const tor_addr_t *addr, uint16_t port) -{ - bridge_info_t *bridge = get_configured_bridge_by_addr_port_digest(addr, - port, - NULL); - return bridge ? bridge->socks_args : NULL; -} - -/** We need to ask <b>bridge</b> for its server descriptor. */ -static void -launch_direct_bridge_descriptor_fetch(bridge_info_t *bridge) -{ - const or_options_t *options = get_options(); - - if (connection_get_by_type_addr_port_purpose( - CONN_TYPE_DIR, &bridge->addr, bridge->port, - DIR_PURPOSE_FETCH_SERVERDESC)) - return; /* it's already on the way */ - - if (routerset_contains_bridge(options->ExcludeNodes, bridge)) { - download_status_mark_impossible(&bridge->fetch_status); - log_warn(LD_APP, "Not using bridge at %s: it is in ExcludeNodes.", - safe_str_client(fmt_and_decorate_addr(&bridge->addr))); - return; - } - - /* Until we get a descriptor for the bridge, we only know one address for - * it. */ - if (!fascist_firewall_allows_address_addr(&bridge->addr, bridge->port, - FIREWALL_OR_CONNECTION, 0, 0)) { - log_notice(LD_CONFIG, "Tried to fetch a descriptor directly from a " - "bridge, but that bridge is not reachable through our " - "firewall."); - return; - } - - directory_initiate_command(&bridge->addr, bridge->port, - NULL, 0, /*no dirport*/ - bridge->identity, - DIR_PURPOSE_FETCH_SERVERDESC, - ROUTER_PURPOSE_BRIDGE, - DIRIND_ONEHOP, "authority.z", NULL, 0, 0); -} - -/** Fetching the bridge descriptor from the bridge authority returned a - * "not found". Fall back to trying a direct fetch. */ -void -retry_bridge_descriptor_fetch_directly(const char *digest) -{ - bridge_info_t *bridge = find_bridge_by_digest(digest); - if (!bridge) - return; /* not found? oh well. */ - - launch_direct_bridge_descriptor_fetch(bridge); -} - -/** For each bridge in our list for which we don't currently have a - * descriptor, fetch a new copy of its descriptor -- either directly - * from the bridge or via a bridge authority. */ -void -fetch_bridge_descriptors(const or_options_t *options, time_t now) -{ - int num_bridge_auths = get_n_authorities(BRIDGE_DIRINFO); - int ask_bridge_directly; - int can_use_bridge_authority; - - if (!bridge_list) - return; - - /* If we still have unconfigured managed proxies, don't go and - connect to a bridge. */ - if (pt_proxies_configuration_pending()) - return; - - SMARTLIST_FOREACH_BEGIN(bridge_list, bridge_info_t *, bridge) - { - if (!download_status_is_ready(&bridge->fetch_status, now, - IMPOSSIBLE_TO_DOWNLOAD)) - continue; /* don't bother, no need to retry yet */ - if (routerset_contains_bridge(options->ExcludeNodes, bridge)) { - download_status_mark_impossible(&bridge->fetch_status); - log_warn(LD_APP, "Not using bridge at %s: it is in ExcludeNodes.", - safe_str_client(fmt_and_decorate_addr(&bridge->addr))); - continue; - } - - /* schedule another fetch as if this one will fail, in case it does */ - download_status_failed(&bridge->fetch_status, 0); - - can_use_bridge_authority = !tor_digest_is_zero(bridge->identity) && - num_bridge_auths; - ask_bridge_directly = !can_use_bridge_authority || - !options->UpdateBridgesFromAuthority; - log_debug(LD_DIR, "ask_bridge_directly=%d (%d, %d, %d)", - ask_bridge_directly, tor_digest_is_zero(bridge->identity), - !options->UpdateBridgesFromAuthority, !num_bridge_auths); - - if (ask_bridge_directly && - !fascist_firewall_allows_address_addr(&bridge->addr, bridge->port, - FIREWALL_OR_CONNECTION, 0, - 0)) { - log_notice(LD_DIR, "Bridge at '%s' isn't reachable by our " - "firewall policy. %s.", - fmt_addrport(&bridge->addr, bridge->port), - can_use_bridge_authority ? - "Asking bridge authority instead" : "Skipping"); - if (can_use_bridge_authority) - ask_bridge_directly = 0; - else - continue; - } - - if (ask_bridge_directly) { - /* we need to ask the bridge itself for its descriptor. */ - launch_direct_bridge_descriptor_fetch(bridge); - } else { - /* We have a digest and we want to ask an authority. We could - * combine all the requests into one, but that may give more - * hints to the bridge authority than we want to give. */ - char resource[10 + HEX_DIGEST_LEN]; - memcpy(resource, "fp/", 3); - base16_encode(resource+3, HEX_DIGEST_LEN+1, - bridge->identity, DIGEST_LEN); - memcpy(resource+3+HEX_DIGEST_LEN, ".z", 3); - log_info(LD_DIR, "Fetching bridge info '%s' from bridge authority.", - resource); - directory_get_from_dirserver(DIR_PURPOSE_FETCH_SERVERDESC, - ROUTER_PURPOSE_BRIDGE, resource, 0, DL_WANT_AUTHORITY); - } - } - SMARTLIST_FOREACH_END(bridge); -} - -/** If our <b>bridge</b> is configured to be a different address than - * the bridge gives in <b>node</b>, rewrite the routerinfo - * we received to use the address we meant to use. Now we handle - * multihomed bridges better. - */ -static void -rewrite_node_address_for_bridge(const bridge_info_t *bridge, node_t *node) -{ - /* XXXX move this function. */ - /* XXXX overridden addresses should really live in the node_t, so that the - * routerinfo_t and the microdesc_t can be immutable. But we can only - * do that safely if we know that no function that connects to an OR - * does so through an address from any source other than node_get_addr(). - */ - tor_addr_t addr; - const or_options_t *options = get_options(); - - if (node->ri) { - routerinfo_t *ri = node->ri; - tor_addr_from_ipv4h(&addr, ri->addr); - - if ((!tor_addr_compare(&bridge->addr, &addr, CMP_EXACT) && - bridge->port == ri->or_port) || - (!tor_addr_compare(&bridge->addr, &ri->ipv6_addr, CMP_EXACT) && - bridge->port == ri->ipv6_orport)) { - /* they match, so no need to do anything */ - } else { - if (tor_addr_family(&bridge->addr) == AF_INET) { - ri->addr = tor_addr_to_ipv4h(&bridge->addr); - ri->or_port = bridge->port; - log_info(LD_DIR, - "Adjusted bridge routerinfo for '%s' to match configured " - "address %s:%d.", - ri->nickname, fmt_addr32(ri->addr), ri->or_port); - } else if (tor_addr_family(&bridge->addr) == AF_INET6) { - tor_addr_copy(&ri->ipv6_addr, &bridge->addr); - ri->ipv6_orport = bridge->port; - log_info(LD_DIR, - "Adjusted bridge routerinfo for '%s' to match configured " - "address %s.", - ri->nickname, fmt_addrport(&ri->ipv6_addr, ri->ipv6_orport)); - } else { - log_err(LD_BUG, "Address family not supported: %d.", - tor_addr_family(&bridge->addr)); - return; - } - } - - if (options->ClientPreferIPv6ORPort == -1) { - /* Mark which address to use based on which bridge_t we got. */ - node->ipv6_preferred = (tor_addr_family(&bridge->addr) == AF_INET6 && - !tor_addr_is_null(&node->ri->ipv6_addr)); - } else { - /* Mark which address to use based on user preference */ - node->ipv6_preferred = (fascist_firewall_prefer_ipv6_orport(options) && - !tor_addr_is_null(&node->ri->ipv6_addr)); - } - - /* XXXipv6 we lack support for falling back to another address for - the same relay, warn the user */ - if (!tor_addr_is_null(&ri->ipv6_addr)) { - tor_addr_port_t ap; - node_get_pref_orport(node, &ap); - log_notice(LD_CONFIG, - "Bridge '%s' has both an IPv4 and an IPv6 address. " - "Will prefer using its %s address (%s) based on %s.", - ri->nickname, - node->ipv6_preferred ? "IPv6" : "IPv4", - fmt_addrport(&ap.addr, ap.port), - options->ClientPreferIPv6ORPort == -1 ? - "the configured Bridge address" : - "ClientPreferIPv6ORPort"); - } - } - if (node->rs) { - routerstatus_t *rs = node->rs; - tor_addr_from_ipv4h(&addr, rs->addr); - - if (!tor_addr_compare(&bridge->addr, &addr, CMP_EXACT) && - bridge->port == rs->or_port) { - /* they match, so no need to do anything */ - } else { - rs->addr = tor_addr_to_ipv4h(&bridge->addr); - rs->or_port = bridge->port; - log_info(LD_DIR, - "Adjusted bridge routerstatus for '%s' to match " - "configured address %s.", - rs->nickname, fmt_addrport(&bridge->addr, rs->or_port)); - } - } -} - -/** We just learned a descriptor for a bridge. See if that - * digest is in our entry guard list, and add it if not. */ -void -learned_bridge_descriptor(routerinfo_t *ri, int from_cache) -{ - tor_assert(ri); - tor_assert(ri->purpose == ROUTER_PURPOSE_BRIDGE); - if (get_options()->UseBridges) { - int first = num_bridges_usable() <= 1; - bridge_info_t *bridge = get_configured_bridge_by_routerinfo(ri); - time_t now = time(NULL); - router_set_status(ri->cache_info.identity_digest, 1); - - if (bridge) { /* if we actually want to use this one */ - node_t *node; - /* it's here; schedule its re-fetch for a long time from now. */ - if (!from_cache) - download_status_reset(&bridge->fetch_status); - - node = node_get_mutable_by_id(ri->cache_info.identity_digest); - tor_assert(node); - rewrite_node_address_for_bridge(bridge, node); - if (tor_digest_is_zero(bridge->identity)) { - memcpy(bridge->identity,ri->cache_info.identity_digest, DIGEST_LEN); - log_notice(LD_DIR, "Learned identity %s for bridge at %s:%d", - hex_str(bridge->identity, DIGEST_LEN), - fmt_and_decorate_addr(&bridge->addr), - (int) bridge->port); - } - add_an_entry_guard(get_guard_selection_info(), node, 1, 1, 0, 0); - - log_notice(LD_DIR, "new bridge descriptor '%s' (%s): %s", ri->nickname, - from_cache ? "cached" : "fresh", router_describe(ri)); - /* set entry->made_contact so if it goes down we don't drop it from - * our entry node list */ - entry_guard_register_connect_status(ri->cache_info.identity_digest, - 1, 0, now); - if (first) { - routerlist_retry_directory_downloads(now); - } - } - } -} - -/** Return the number of bridges that have descriptors that - * are marked with purpose 'bridge' and are running. - * - * We use this function to decide if we're ready to start building - * circuits through our bridges, or if we need to wait until the - * directory "server/authority" requests finish. */ -int -any_bridge_descriptors_known(void) -{ - tor_assert(get_options()->UseBridges); - return choose_random_entry(NULL) != NULL; -} - -/** Return the number of bridges that have descriptors that are marked with - * purpose 'bridge' and are running. - */ -static int -num_bridges_usable(void) -{ - int n_options = 0; - tor_assert(get_options()->UseBridges); - (void) choose_random_entry_impl(get_guard_selection_info(), - NULL, 0, 0, &n_options); - return n_options; -} - -/** Return a smartlist containing all bridge identity digests */ -MOCK_IMPL(smartlist_t *, -list_bridge_identities, (void)) -{ - smartlist_t *result = NULL; - char *digest_tmp; - - if (get_options()->UseBridges && bridge_list) { - result = smartlist_new(); - - SMARTLIST_FOREACH_BEGIN(bridge_list, bridge_info_t *, b) { - digest_tmp = tor_malloc(DIGEST_LEN); - memcpy(digest_tmp, b->identity, DIGEST_LEN); - smartlist_add(result, digest_tmp); - } SMARTLIST_FOREACH_END(b); - } - - return result; -} - -/** Get the download status for a bridge descriptor given its identity */ -MOCK_IMPL(download_status_t *, -get_bridge_dl_status_by_id, (const char *digest)) -{ - download_status_t *dl = NULL; - - if (digest && get_options()->UseBridges && bridge_list) { - SMARTLIST_FOREACH_BEGIN(bridge_list, bridge_info_t *, b) { - if (tor_memeq(digest, b->identity, DIGEST_LEN)) { - dl = &(b->fetch_status); - break; - } - } SMARTLIST_FOREACH_END(b); - } - - return dl; -} - /** Return 1 if we have at least one descriptor for an entry guard * (bridge or member of EntryNodes) and all descriptors we know are * down. Else return 0. If <b>act</b> is 1, then mark the down guards @@ -3163,9 +2392,6 @@ entry_guards_free_all(void) smartlist_free(guard_contexts); guard_contexts = NULL; } - clear_bridge_list(); - smartlist_free(bridge_list); - bridge_list = NULL; circuit_build_times_free_timeouts(get_circuit_build_times_mutable()); }
diff --git a/src/or/entrynodes.h b/src/or/entrynodes.h index 5c0857b..8407945 100644 --- a/src/or/entrynodes.h +++ b/src/or/entrynodes.h @@ -221,41 +221,11 @@ int is_node_used_as_guard_for_guard_selection(guard_selection_t *gs, const node_t *node); MOCK_DECL(int, is_node_used_as_guard, (const node_t *node));
-void mark_bridge_list(void); -void sweep_bridge_list(void); - -int addr_is_a_configured_bridge(const tor_addr_t *addr, uint16_t port, - const char *digest); -int extend_info_is_a_configured_bridge(const extend_info_t *ei); -int routerinfo_is_a_configured_bridge(const routerinfo_t *ri); -int node_is_a_configured_bridge(const node_t *node); -void learned_router_identity(const tor_addr_t *addr, uint16_t port, - const char *digest); -struct bridge_line_t; -void bridge_add_from_config(struct bridge_line_t *bridge_line); -void retry_bridge_descriptor_fetch_directly(const char *digest); -void fetch_bridge_descriptors(const or_options_t *options, time_t now); -void learned_bridge_descriptor(routerinfo_t *ri, int from_cache); -int any_bridge_descriptors_known(void); int entries_known_but_down(const or_options_t *options); void entries_retry_all(const or_options_t *options);
-const smartlist_t *get_socks_args_by_bridge_addrport(const tor_addr_t *addr, - uint16_t port); - -int any_bridges_dont_support_microdescriptors(void); - void entry_guards_free_all(void);
-const char *find_transport_name_by_bridge_addrport(const tor_addr_t *addr, - uint16_t port); -struct transport_t; -int get_transport_by_bridge_addrport(const tor_addr_t *addr, uint16_t port, - const struct transport_t **transport); - -MOCK_DECL(int, transport_is_needed, (const char *transport_name)); -int validate_pluggable_transports_config(void); - double pathbias_get_close_success_count(entry_guard_t *guard); double pathbias_get_use_success_count(entry_guard_t *guard);
@@ -275,9 +245,5 @@ guard_get_guardfraction_bandwidth(guardfraction_bandwidth_t *guardfraction_bw, int orig_bandwidth, uint32_t guardfraction_percentage);
-MOCK_DECL(smartlist_t *, list_bridge_identities, (void)); -MOCK_DECL(download_status_t *, get_bridge_dl_status_by_id, - (const char *digest)); - #endif
diff --git a/src/or/include.am b/src/or/include.am index 10f8b85..278aa9b 100644 --- a/src/or/include.am +++ b/src/or/include.am @@ -19,6 +19,7 @@ EXTRA_DIST+= src/or/ntmain.c src/or/Makefile.nmake
LIBTOR_A_SOURCES = \ src/or/addressmap.c \ + src/or/bridges.c \ src/or/buffers.c \ src/or/channel.c \ src/or/channeltls.c \ @@ -130,6 +131,7 @@ endif
ORHEADERS = \ src/or/addressmap.h \ + src/or/bridges.h \ src/or/buffers.h \ src/or/channel.h \ src/or/channeltls.h \ diff --git a/src/or/main.c b/src/or/main.c index c10f627..a508003 100644 --- a/src/or/main.c +++ b/src/or/main.c @@ -50,6 +50,7 @@ #include "or.h" #include "addressmap.h" #include "backtrace.h" +#include "bridges.h" #include "buffers.h" #include "channel.h" #include "channeltls.h" @@ -3114,6 +3115,7 @@ tor_free_all(int postfork) control_free_all(); sandbox_free_getaddrinfo_cache(); protover_free_all(); + bridges_free_all(); if (!postfork) { config_free_all(); or_state_free_all(); diff --git a/src/or/networkstatus.c b/src/or/networkstatus.c index 316ce48..ec8f77f 100644 --- a/src/or/networkstatus.c +++ b/src/or/networkstatus.c @@ -38,6 +38,7 @@
#define NETWORKSTATUS_PRIVATE #include "or.h" +#include "bridges.h" #include "channel.h" #include "circuitmux.h" #include "circuitmux_ewma.h" diff --git a/src/or/routerlist.c b/src/or/routerlist.c index c99d22e..f51b50e 100644 --- a/src/or/routerlist.c +++ b/src/or/routerlist.c @@ -93,6 +93,7 @@ #define ROUTERLIST_PRIVATE #include "or.h" #include "backtrace.h" +#include "bridges.h" #include "crypto_ed25519.h" #include "circuitstats.h" #include "config.h" diff --git a/src/or/transports.c b/src/or/transports.c index f755882..feeff6e 100644 --- a/src/or/transports.c +++ b/src/or/transports.c @@ -91,13 +91,13 @@
#define PT_PRIVATE #include "or.h" +#include "bridges.h" #include "config.h" #include "circuitbuild.h" #include "transports.h" #include "util.h" #include "router.h" #include "statefile.h" -#include "entrynodes.h" #include "connection_or.h" #include "ext_orport.h" #include "control.h" diff --git a/src/test/test_config.c b/src/test/test_config.c index 2fc37b0..cf047f0 100644 --- a/src/test/test_config.c +++ b/src/test/test_config.c @@ -11,6 +11,7 @@ #include "or.h" #include "address.h" #include "addressmap.h" +#include "bridges.h" #include "circuitmux_ewma.h" #include "circuitbuild.h" #include "config.h" diff --git a/src/test/test_controller.c b/src/test/test_controller.c index f19c846..4e65d76 100644 --- a/src/test/test_controller.c +++ b/src/test/test_controller.c @@ -3,6 +3,7 @@
#define CONTROL_PRIVATE #include "or.h" +#include "bridges.h" #include "control.h" #include "entrynodes.h" #include "networkstatus.h"