/* Copyright (c) 2001 Matej Pfajfar. * Copyright (c) 2001-2004, Roger Dingledine. * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. */ /* See LICENSE for licensing information */ /* $Id$ */ const char routerlist_c_id[] = "$Id$"; /** * \file routerlist.c * \brief Code to * maintain and access the global list of routerinfos for known * servers. **/ #include "or.h" /****************************************************************************/ /* static function prototypes */ static routerstatus_t *router_pick_directory_server_impl(int requireother, int fascistfirewall, int for_v2_directory); static routerstatus_t *router_pick_trusteddirserver_impl( int need_v1_authority, int requireother, int fascistfirewall); static void mark_all_trusteddirservers_up(void); static int router_nickname_is_in_list(routerinfo_t *router, const char *list); static int router_nickname_matches(routerinfo_t *router, const char *nickname); static void routerstatus_list_update_from_networkstatus(time_t now); static void local_routerstatus_free(local_routerstatus_t *rs); static void trusted_dir_server_free(trusted_dir_server_t *ds); static void update_networkstatus_cache_downloads(time_t now); static void update_networkstatus_client_downloads(time_t now); static int signed_desc_digest_is_recognized(signed_descriptor_t *desc); static void routerlist_assert_ok(routerlist_t *rl); static int have_tried_downloading_all_statuses(int n_failures); static routerstatus_t *networkstatus_find_entry(networkstatus_t *ns, const char *digest); /****************************************************************************/ /** Global list of a trusted_dir_server_t object for each trusted directory * server. */ static smartlist_t *trusted_dir_servers = NULL; /** Global list of all of the routers that we know about. */ static routerlist_t *routerlist = NULL; /** Global list of all of the current network_status documents that we know * about. This list is kept sorted by published_on. */ static smartlist_t *networkstatus_list = NULL; /** Global list of local_routerstatus_t for each router, known or unknown. */ static smartlist_t *routerstatus_list = NULL; /** True iff any member of networkstatus_list has changed since the last time * we called routerstatus_list_update_from_networkstatus(). */ static int networkstatus_list_has_changed = 0; /** True iff any element of routerstatus_list has changed since the last * time we called routers_update_all_from_networkstatus().*/ static int routerstatus_list_has_changed = 0; /** List of strings for nicknames we've already warned about and that are * still unknown / unavailable. */ static smartlist_t *warned_nicknames = NULL; /** List of strings for nicknames or fingerprints we've already warned about * and that are still conflicted. */ static smartlist_t *warned_conflicts = NULL; /** The last time we tried to download any routerdesc, or 0 for "never". We * use this to rate-limit download attempts when the number of routerdescs to * download is low. */ static time_t last_routerdesc_download_attempted = 0; /** The last time we tried to download a networkstatus, or 0 for "never". We * use this to rate-limit download attempts for directory caches (including * mirrors). Clients don't use this now. */ static time_t last_networkstatus_download_attempted = 0; /** True iff we have logged a warning about this OR not being valid or * not being named. */ static int have_warned_about_invalid_status = 0; /** True iff we have logged a warning about this OR's version being older than * listed by the authorities */ static int have_warned_about_old_version = 0; /** True iff we have logged a warning about this OR's version being newer than * listed by the authorities */ static int have_warned_about_new_version = 0; /** Repopulate our list of network_status_t objects from the list cached on * disk. Return 0 on success, -1 on failure. */ int router_reload_networkstatus(void) { char filename[512]; struct stat st; smartlist_t *entries; char *s; tor_assert(get_options()->DataDirectory); if (!networkstatus_list) networkstatus_list = smartlist_create(); tor_snprintf(filename,sizeof(filename),"%s/cached-status", get_options()->DataDirectory); entries = tor_listdir(filename); SMARTLIST_FOREACH(entries, const char *, fn, { char buf[DIGEST_LEN]; if (strlen(fn) != HEX_DIGEST_LEN || base16_decode(buf, sizeof(buf), fn, strlen(fn))) { log_info(LD_DIR, "Skipping cached-status file with unexpected name \"%s\"",fn); continue; } tor_snprintf(filename,sizeof(filename),"%s/cached-status/%s", get_options()->DataDirectory, fn); s = read_file_to_str(filename, 0); if (s) { stat(filename, &st); if (router_set_networkstatus(s, st.st_mtime, NS_FROM_CACHE, NULL)<0) { log_warn(LD_FS, "Couldn't load networkstatus from \"%s\"",filename); } tor_free(s); } }); SMARTLIST_FOREACH(entries, char *, fn, tor_free(fn)); smartlist_free(entries); networkstatus_list_clean(time(NULL)); routers_update_all_from_networkstatus(); return 0; } /* Router descriptor storage. * * Routerdescs are stored in a big file, named "cached-routers". As new * routerdescs arrive, we append them to a journal file named * "cached-routers.new". * * From time to time, we replace "cached-routers" with a new file containing * only the live, non-superseded descriptors, and clear cached-routers.new. * * On startup, we read both files. */ /** The size of the router log, in bytes. */ static size_t router_journal_len = 0; /** The size of the router store, in bytes. */ static size_t router_store_len = 0; /** Total bytes dropped since last rebuild. */ static size_t router_bytes_dropped = 0; /** Helper: return 1 iff the router log is so big we want to rebuild the * store. */ static int router_should_rebuild_store(void) { if (router_store_len > (1<<16)) return (router_journal_len > router_store_len / 2 || router_bytes_dropped > router_store_len / 2); else return router_journal_len > (1<<15); } /** Add the len-type router descriptor in s to the router * journal. */ static int router_append_to_journal(signed_descriptor_t *desc) { or_options_t *options = get_options(); size_t fname_len = strlen(options->DataDirectory)+32; char *fname = tor_malloc(fname_len); const char *body = signed_descriptor_get_body(desc); size_t len = desc->signed_descriptor_len; tor_snprintf(fname, fname_len, "%s/cached-routers.new", options->DataDirectory); tor_assert(len == strlen(body)); if (append_bytes_to_file(fname, body, len, 0)) { log_warn(LD_FS, "Unable to store router descriptor"); tor_free(fname); return -1; } tor_free(fname); router_journal_len += len; return 0; } /** If the journal is too long, or if force is true, then atomically * replace the router store with the routers currently in our routerlist, and * clear the journal. Return 0 on success, -1 on failure. */ static int router_rebuild_store(int force) { size_t len = 0; or_options_t *options; size_t fname_len; smartlist_t *chunk_list = NULL; char *fname = NULL; int r = -1, i; if (!force && !router_should_rebuild_store()) return 0; if (!routerlist) return 0; /* Don't save deadweight. */ routerlist_remove_old_routers(); options = get_options(); fname_len = strlen(options->DataDirectory)+32; fname = tor_malloc(fname_len); tor_snprintf(fname, fname_len, "%s/cached-routers", options->DataDirectory); chunk_list = smartlist_create(); for (i = 0; i < 2; ++i) { smartlist_t *lst = (i == 0) ? routerlist->old_routers : routerlist->routers; SMARTLIST_FOREACH(lst, void *, ptr, { signed_descriptor_t *sd = (i==0) ? ((signed_descriptor_t*)ptr): &((routerinfo_t*)ptr)->cache_info; sized_chunk_t *c; const char *body = signed_descriptor_get_body(sd); if (!body) { log_warn(LD_BUG, "Bug! No descriptor available for router."); goto done; } c = tor_malloc(sizeof(sized_chunk_t)); c->bytes = body; c->len = sd->signed_descriptor_len; smartlist_add(chunk_list, c); }); } if (write_chunks_to_file(fname, chunk_list, 0)<0) { log_warn(LD_FS, "Error writing router store to disk."); goto done; } tor_snprintf(fname, fname_len, "%s/cached-routers.new", options->DataDirectory); write_str_to_file(fname, "", 0); r = 0; router_store_len = len; router_journal_len = 0; router_bytes_dropped = 0; done: tor_free(fname); if (chunk_list) { SMARTLIST_FOREACH(chunk_list, sized_chunk_t *, c, tor_free(c)); smartlist_free(chunk_list); } return r; } /* Load all cached router descriptors from the store. Return 0 on success and * -1 on failure. */ int router_reload_router_list(void) { or_options_t *options = get_options(); size_t fname_len = strlen(options->DataDirectory)+32; char *fname = tor_malloc(fname_len); struct stat st; int j; if (!routerlist) router_get_routerlist(); /* mallocs and inits it in place */ router_journal_len = router_store_len = 0; for (j = 0; j < 2; ++j) { char *contents; tor_snprintf(fname, fname_len, (j==0)?"%s/cached-routers":"%s/cached-routers.new", options->DataDirectory); contents = read_file_to_str(fname, 0); if (contents) { stat(fname, &st); if (j==0) router_store_len = st.st_size; else router_journal_len = st.st_size; router_load_routers_from_string(contents, 1, NULL); tor_free(contents); } } tor_free(fname); if (router_journal_len) { /* Always clear the journal on startup.*/ router_rebuild_store(1); } else { /* Don't cache expired routers. (This is in an else because * router_rebuild_store() also calls remove_old_routers().) */ routerlist_remove_old_routers(); } return 0; } /** Return a smartlist containing a list of trusted_dir_server_t * for all * known trusted dirservers. Callers must not modify the list or its * contents. */ smartlist_t * router_get_trusted_dir_servers(void) { if (!trusted_dir_servers) trusted_dir_servers = smartlist_create(); return trusted_dir_servers; } /** Try to find a running dirserver. If there are no running dirservers * in our routerlist and retry_if_no_servers is non-zero, * set all the authoritative ones as running again, and pick one; * if there are then no dirservers at all in our routerlist, * reload the routerlist and try one last time. If for_runningrouters is * true, then only pick a dirserver that can answer runningrouters queries * (that is, a trusted dirserver, or one running 0.0.9rc5-cvs or later). * Don't pick an authority if any non-authority is viable. * Other args are as in router_pick_directory_server_impl(). */ routerstatus_t * router_pick_directory_server(int requireother, int fascistfirewall, int for_v2_directory, int retry_if_no_servers) { routerstatus_t *choice; if (!routerlist) return NULL; choice = router_pick_directory_server_impl(requireother, fascistfirewall, for_v2_directory); if (choice || !retry_if_no_servers) return choice; log_info(LD_DIR, "No reachable router entries for dirservers. " "Trying them all again."); /* mark all authdirservers as up again */ mark_all_trusteddirservers_up(); /* try again */ choice = router_pick_directory_server_impl(requireother, fascistfirewall, for_v2_directory); if (choice) return choice; log_info(LD_DIR,"Still no %s router entries. Reloading and trying again.", fascistfirewall ? "reachable" : "known"); if (router_reload_router_list()) { return NULL; } /* give it one last try */ choice = router_pick_directory_server_impl(requireother, fascistfirewall, for_v2_directory); return choice; } /** Return the trusted_dir_server_t for the directory authority whose identity * key hashes to digest, or NULL if no such authority is known. */ trusted_dir_server_t * router_get_trusteddirserver_by_digest(const char *digest) { if (!trusted_dir_servers) return NULL; SMARTLIST_FOREACH(trusted_dir_servers, trusted_dir_server_t *, ds, { if (!memcmp(ds->digest, digest, DIGEST_LEN)) return ds; }); return NULL; } /** Try to find a running trusted dirserver. If there are no running * trusted dirservers and retry_if_no_servers is non-zero, * set them all as running again, and try again. * If need_v1_authority is set, return only trusted servers * that are authorities for the V1 directory protocol. * Other args are as in router_pick_trusteddirserver_impl(). */ routerstatus_t * router_pick_trusteddirserver(int need_v1_authority, int requireother, int fascistfirewall, int retry_if_no_servers) { routerstatus_t *choice; choice = router_pick_trusteddirserver_impl(need_v1_authority, requireother, fascistfirewall); if (choice || !retry_if_no_servers) return choice; log_info(LD_DIR, "No trusted dirservers are reachable. Trying them all again."); mark_all_trusteddirservers_up(); return router_pick_trusteddirserver_impl(need_v1_authority, requireother, fascistfirewall); } /** Pick a random running valid directory server/mirror from our * routerlist. Don't pick an authority if any non-authorities are viable. * If fascistfirewall, * make sure the router we pick is allowed by our firewall options. * If requireother, it cannot be us. If for_v2_directory, * choose a directory server new enough to support the v2 directory * functionality. */ static routerstatus_t * router_pick_directory_server_impl(int requireother, int fascistfirewall, int for_v2_directory) { routerstatus_t *result; smartlist_t *sl; smartlist_t *trusted; if (!routerstatus_list) return NULL; /* Find all the running dirservers we know about. */ sl = smartlist_create(); trusted = smartlist_create(); SMARTLIST_FOREACH(routerstatus_list, local_routerstatus_t *, _local_status, { routerstatus_t *status = &(_local_status->status); int is_trusted; if (!status->is_running || !status->dir_port || !status->is_valid) continue; if (requireother && router_digest_is_me(status->identity_digest)) continue; if (fascistfirewall) { if (!fascist_firewall_allows_address_dir(status->addr, status->dir_port)) continue; } is_trusted = router_digest_is_trusted_dir(status->identity_digest); if (for_v2_directory && !(status->is_v2_dir || is_trusted)) continue; smartlist_add(is_trusted ? trusted : sl, status); }); if (smartlist_len(sl)) result = smartlist_choose(sl); else result = smartlist_choose(trusted); smartlist_free(sl); smartlist_free(trusted); return result; } /** Choose randomly from among the trusted dirservers that are up. If * fascistfirewall, make sure the port we pick is allowed by our * firewall options. If requireother, it cannot be us. If * need_v1_authority, choose a trusted authority for the v1 directory * system. */ static routerstatus_t * router_pick_trusteddirserver_impl(int need_v1_authority, int requireother, int fascistfirewall) { smartlist_t *sl; routerinfo_t *me; routerstatus_t *rs; sl = smartlist_create(); me = router_get_my_routerinfo(); if (!trusted_dir_servers) return NULL; SMARTLIST_FOREACH(trusted_dir_servers, trusted_dir_server_t *, d, { if (!d->is_running) continue; if (need_v1_authority && !d->is_v1_authority) continue; if (requireother && me && router_digest_is_me(d->digest)) continue; if (fascistfirewall) { if (!fascist_firewall_allows_address_dir(d->addr, d->dir_port)) continue; } smartlist_add(sl, &d->fake_status); }); rs = smartlist_choose(sl); smartlist_free(sl); return rs; } /** Go through and mark the authoritative dirservers as up. */ static void mark_all_trusteddirservers_up(void) { if (routerlist) { SMARTLIST_FOREACH(routerlist->routers, routerinfo_t *, router, if (router_digest_is_trusted_dir(router->cache_info.identity_digest) && router->dir_port > 0) { router->is_running = 1; }); } if (trusted_dir_servers) { SMARTLIST_FOREACH(trusted_dir_servers, trusted_dir_server_t *, dir, { local_routerstatus_t *rs; dir->is_running = 1; dir->n_networkstatus_failures = 0; rs = router_get_combined_status_by_digest(dir->digest); if (rs) rs->status.is_running = 1; }); } last_networkstatus_download_attempted = 0; } /** Reset all internal variables used to count failed downloads of network * status objects. */ void router_reset_status_download_failures(void) { mark_all_trusteddirservers_up(); } /** Add all the family of router to the smartlist sl. * This is used to make sure we don't pick siblings in a single path. */ void routerlist_add_family(smartlist_t *sl, routerinfo_t *router) { routerinfo_t *r; config_line_t *cl; if (!router->declared_family) return; /* Add every r such that router declares familyness with r, and r * declares familyhood with router. */ SMARTLIST_FOREACH(router->declared_family, const char *, n, { if (!(r = router_get_by_nickname(n, 0))) continue; if (!r->declared_family) continue; SMARTLIST_FOREACH(r->declared_family, const char *, n2, { if (router_nickname_matches(router, n2)) smartlist_add(sl, r); }); }); /* If the user declared any families locally, honor those too. */ for (cl = get_options()->NodeFamilies; cl; cl = cl->next) { if (router_nickname_is_in_list(router, cl->value)) { add_nickname_list_to_smartlist(sl, cl->value, 0, 1, 1); } } } /** Given a comma-and-whitespace separated list of nicknames, see which * nicknames in list name routers in our routerlist that are * currently running. Add the routerinfos for those routers to sl. */ void add_nickname_list_to_smartlist(smartlist_t *sl, const char *list, int must_be_running, int warn_if_down, int warn_if_unnamed) { routerinfo_t *router; smartlist_t *nickname_list; int have_dir_info = router_have_minimum_dir_info(); if (!list) return; /* nothing to do */ tor_assert(sl); nickname_list = smartlist_create(); if (!warned_nicknames) warned_nicknames = smartlist_create(); smartlist_split_string(nickname_list, list, ",", SPLIT_SKIP_SPACE|SPLIT_IGNORE_BLANK, 0); SMARTLIST_FOREACH(nickname_list, const char *, nick, { int warned; if (!is_legal_nickname_or_hexdigest(nick)) { log_warn(LD_CONFIG, "Nickname '%s' is misformed; skipping", nick); continue; } router = router_get_by_nickname(nick, warn_if_unnamed); warned = smartlist_string_isin(warned_nicknames, nick); if (router) { if (!must_be_running || router->is_running) { smartlist_add(sl,router); if (warned) smartlist_string_remove(warned_nicknames, nick); } else { if (!warned) { log_fn(warn_if_down ? LOG_WARN : LOG_DEBUG, LD_CONFIG, "Nickname list includes '%s' which is known but down.",nick); smartlist_add(warned_nicknames, tor_strdup(nick)); } } } else { if (!warned) { log_fn(have_dir_info ? LOG_WARN : LOG_INFO, LD_CONFIG, "Nickname list includes '%s' which isn't a known router.",nick); smartlist_add(warned_nicknames, tor_strdup(nick)); } } }); SMARTLIST_FOREACH(nickname_list, char *, nick, tor_free(nick)); smartlist_free(nickname_list); } /** Return 1 iff any member of the comma-separated list list is an * acceptable nickname or hexdigest for router. Else return 0. */ static int router_nickname_is_in_list(routerinfo_t *router, const char *list) { smartlist_t *nickname_list; int v = 0; if (!list) return 0; /* definitely not */ tor_assert(router); nickname_list = smartlist_create(); smartlist_split_string(nickname_list, list, ",", SPLIT_SKIP_SPACE|SPLIT_IGNORE_BLANK, 0); SMARTLIST_FOREACH(nickname_list, const char *, cp, if (router_nickname_matches(router, cp)) {v=1;break;}); SMARTLIST_FOREACH(nickname_list, char *, cp, tor_free(cp)); smartlist_free(nickname_list); return v; } /** Add every router from our routerlist that is currently running to * sl, so that we can pick a node for a circuit. */ static void router_add_running_routers_to_smartlist(smartlist_t *sl, int allow_invalid, int need_uptime, int need_capacity, int need_guard) { if (!routerlist) return; SMARTLIST_FOREACH(routerlist->routers, routerinfo_t *, router, { if (router->is_running && router->purpose == ROUTER_PURPOSE_GENERAL && (router->is_valid || /* XXX this next part is wrong and should be fixed one day -RD */ (allow_invalid && !router_is_unreliable(router, need_uptime, need_capacity, need_guard)))) { /* If it's running, and either it's valid or we're ok picking * invalid routers and this one is suitable. */ smartlist_add(sl, router); } }); } /** Look through the routerlist until we find a router that has my key. Return it. */ routerinfo_t * routerlist_find_my_routerinfo(void) { if (!routerlist) return NULL; SMARTLIST_FOREACH(routerlist->routers, routerinfo_t *, router, { if (router_is_me(router)) return router; }); return NULL; } /** Find a router that's up, that has this IP address, and * that allows exit to this address:port, or return NULL if there * isn't a good one. */ routerinfo_t * router_find_exact_exit_enclave(const char *address, uint16_t port) { uint32_t addr; struct in_addr in; if (!tor_inet_aton(address, &in)) return NULL; /* it's not an IP already */ addr = ntohl(in.s_addr); SMARTLIST_FOREACH(routerlist->routers, routerinfo_t *, router, { if (router->is_running && router->addr == addr && compare_addr_to_addr_policy(addr, port, router->exit_policy) == ADDR_POLICY_ACCEPTED) return router; }); return NULL; } /** Return 1 if router is not suitable for these parameters, else 0. * If need_uptime is non-zero, we require a minimum uptime. * If need_capacity is non-zero, we require a minimum advertised * bandwidth. */ int router_is_unreliable(routerinfo_t *router, int need_uptime, int need_capacity, int need_guard) { if (need_uptime && !router->is_stable) return 1; if (need_capacity && !router->is_fast) return 1; if (need_guard && !router->is_possible_guard) return 1; return 0; } /** Remove from routerlist sl all routers that are not * sufficiently stable. */ static void routerlist_sl_remove_unreliable_routers(smartlist_t *sl, int need_uptime, int need_capacity, int need_guard) { int i; routerinfo_t *router; for (i = 0; i < smartlist_len(sl); ++i) { router = smartlist_get(sl, i); if (router_is_unreliable(router, need_uptime, need_capacity, need_guard)) { // log(LOG_DEBUG, "Router '%s' has insufficient uptime; deleting.", // router->nickname); smartlist_del(sl, i--); } } } /** Return the smaller of the router's configured BandwidthRate * and its advertised capacity. */ uint32_t router_get_advertised_bandwidth(routerinfo_t *router) { if (router->bandwidthcapacity < router->bandwidthrate) return router->bandwidthcapacity; return router->bandwidthrate; } #define MAX_BELIEVABLE_BANDWIDTH 1500000 /* 1.5 MB/sec */ /** Choose a random element of router list sl, weighted by * the advertised bandwidth of each router. */ routerinfo_t * routerlist_sl_choose_by_bandwidth(smartlist_t *sl) { int i; routerinfo_t *router; smartlist_t *bandwidths; uint32_t this_bw, tmp, total_bw=0, rand_bw; uint32_t *p; /* First count the total bandwidth weight, and make a smartlist * of each value. */ bandwidths = smartlist_create(); for (i = 0; i < smartlist_len(sl); ++i) { router = smartlist_get(sl, i); this_bw = router_get_advertised_bandwidth(router); /* if they claim something huge, don't believe it */ if (this_bw > MAX_BELIEVABLE_BANDWIDTH) this_bw = MAX_BELIEVABLE_BANDWIDTH; p = tor_malloc(sizeof(uint32_t)); *p = this_bw; smartlist_add(bandwidths, p); total_bw += this_bw; } if (!total_bw) { SMARTLIST_FOREACH(bandwidths, uint32_t*, p, tor_free(p)); smartlist_free(bandwidths); return smartlist_choose(sl); } /* Second, choose a random value from the bandwidth weights. */ rand_bw = crypto_rand_int(total_bw); /* Last, count through sl until we get to the element we picked */ tmp = 0; for (i=0; ; i++) { tor_assert(i < smartlist_len(sl)); p = smartlist_get(bandwidths, i); tmp += *p; if (tmp >= rand_bw) break; } SMARTLIST_FOREACH(bandwidths, uint32_t*, p, tor_free(p)); smartlist_free(bandwidths); return (routerinfo_t *)smartlist_get(sl, i); } /** Return a random running router from the routerlist. If any node * named in preferred is available, pick one of those. Never * pick a node named in excluded, or whose routerinfo is in * excludedsmartlist, even if they are the only nodes * available. If strict is true, never pick any node besides * those in preferred. * If need_uptime is non-zero and any router has more than * a minimum uptime, return one of those. * If need_capacity is non-zero, weight your choice by the * advertised capacity of each router. */ routerinfo_t * router_choose_random_node(const char *preferred, const char *excluded, smartlist_t *excludedsmartlist, int need_uptime, int need_capacity, int need_guard, int allow_invalid, int strict) { smartlist_t *sl, *excludednodes; routerinfo_t *choice = NULL; excludednodes = smartlist_create(); add_nickname_list_to_smartlist(excludednodes,excluded,0,0,1); /* Try the preferred nodes first. Ignore need_uptime and need_capacity * and need_guard, since the user explicitly asked for these nodes. */ if (preferred) { sl = smartlist_create(); add_nickname_list_to_smartlist(sl,preferred,1,1,1); smartlist_subtract(sl,excludednodes); if (excludedsmartlist) smartlist_subtract(sl,excludedsmartlist); choice = smartlist_choose(sl); smartlist_free(sl); } if (!choice && !strict) { /* Then give up on our preferred choices: any node * will do that has the required attributes. */ sl = smartlist_create(); router_add_running_routers_to_smartlist(sl, allow_invalid, need_uptime, need_capacity, need_guard); smartlist_subtract(sl,excludednodes); if (excludedsmartlist) smartlist_subtract(sl,excludedsmartlist); routerlist_sl_remove_unreliable_routers(sl, need_uptime, need_capacity, need_guard); if (need_capacity) choice = routerlist_sl_choose_by_bandwidth(sl); else choice = smartlist_choose(sl); smartlist_free(sl); if (!choice && (need_uptime || need_capacity || need_guard)) { /* try once more -- recurse but with fewer restrictions. */ log_info(LD_CIRC, "We couldn't find any live%s%s%s routers; falling back " "to list of all routers.", need_capacity?", fast":"", need_uptime?", stable":"", need_guard?", guard":""); choice = router_choose_random_node( NULL, excluded, excludedsmartlist, 0, 0, 0, allow_invalid, 0); } } smartlist_free(excludednodes); if (!choice) log_warn(LD_CIRC, "No available nodes when trying to choose node. Failing."); return choice; } /** Return true iff the digest of router's identity key, * encoded in hexadecimal, matches hexdigest (which is * optionally prefixed with a single dollar sign). Return false if * hexdigest is malformed, or it doesn't match. */ static INLINE int router_hex_digest_matches(routerinfo_t *router, const char *hexdigest) { char digest[DIGEST_LEN]; tor_assert(hexdigest); if (hexdigest[0] == '$') ++hexdigest; if (strlen(hexdigest) != HEX_DIGEST_LEN || base16_decode(digest, DIGEST_LEN, hexdigest, HEX_DIGEST_LEN)<0) return 0; return (!memcmp(digest, router->cache_info.identity_digest, DIGEST_LEN)); } /** Return true if router's nickname matches nickname * (case-insensitive), or if router's identity key digest * matches a hexadecimal value stored in nickname. Return * false otherwise. */ static int router_nickname_matches(routerinfo_t *router, const char *nickname) { if (nickname[0]!='$' && !strcasecmp(router->nickname, nickname)) return 1; return router_hex_digest_matches(router, nickname); } /** Return the router in our routerlist whose (case-insensitive) * nickname or (case-sensitive) hexadecimal key digest is * nickname. Return NULL if no such router is known. */ routerinfo_t * router_get_by_nickname(const char *nickname, int warn_if_unnamed) { int maybedigest; char digest[DIGEST_LEN]; routerinfo_t *best_match=NULL; int n_matches = 0; tor_assert(nickname); if (!routerlist) return NULL; if (nickname[0] == '$') return router_get_by_hexdigest(nickname); if (server_mode(get_options()) && !strcasecmp(nickname, get_options()->Nickname)) return router_get_my_routerinfo(); maybedigest = (strlen(nickname) == HEX_DIGEST_LEN) && (base16_decode(digest,DIGEST_LEN,nickname,HEX_DIGEST_LEN) == 0); SMARTLIST_FOREACH(routerlist->routers, routerinfo_t *, router, { if (!strcasecmp(router->nickname, nickname)) { if (router->is_named) return router; else { ++n_matches; if (n_matches <= 1 || router->is_running) best_match = router; } } else if (maybedigest && !memcmp(digest, router->cache_info.identity_digest, DIGEST_LEN) ) { return router; } }); if (best_match) { if (warn_if_unnamed && n_matches > 1) { smartlist_t *fps = smartlist_create(); int any_unwarned = 0; SMARTLIST_FOREACH(routerlist->routers, routerinfo_t *, router, { local_routerstatus_t *rs; char *desc; size_t dlen; char fp[HEX_DIGEST_LEN+1]; if (strcasecmp(router->nickname, nickname)) continue; rs = router_get_combined_status_by_digest( router->cache_info.identity_digest); if (rs && !rs->name_lookup_warned) { rs->name_lookup_warned = 1; any_unwarned = 1; } base16_encode(fp, sizeof(fp), router->cache_info.identity_digest, DIGEST_LEN); dlen = 32 + HEX_DIGEST_LEN + strlen(router->address); desc = tor_malloc(dlen); tor_snprintf(desc, dlen, "\"$%s\" for the one at %s:%d", fp, router->address, router->or_port); smartlist_add(fps, desc); }); if (any_unwarned) { char *alternatives = smartlist_join_strings(fps, "; ",0,NULL); log_warn(LD_CONFIG, "There are multiple matches for the nickname \"%s\"," " but none is listed as named by the directory authories. " "Choosing one arbitrarily. If you meant one in particular, " "you should say %s.", nickname, alternatives); tor_free(alternatives); } SMARTLIST_FOREACH(fps, char *, cp, tor_free(cp)); smartlist_free(fps); } else if (warn_if_unnamed) { local_routerstatus_t *rs = router_get_combined_status_by_digest( best_match->cache_info.identity_digest); if (rs && !rs->name_lookup_warned) { char fp[HEX_DIGEST_LEN+1]; base16_encode(fp, sizeof(fp), best_match->cache_info.identity_digest, DIGEST_LEN); log_warn(LD_CONFIG, "You specified a server \"%s\" by name, but the " "directory authorities do not have a listing for this name. " "To make sure you get the same server in the future, refer to " "it by key, as \"$%s\".", nickname, fp); rs->name_lookup_warned = 1; } } return best_match; } return NULL; } /** Try to find a routerinfo for digest. If we don't have one, * return 1. If we do, ask tor_version_as_new_as() for the answer. */ int router_digest_version_as_new_as(const char *digest, const char *cutoff) { routerinfo_t *router = router_get_by_digest(digest); if (!router) return 1; return tor_version_as_new_as(router->platform, cutoff); } /** Return true iff digest is the digest of the identity key of * a trusted directory. */ int router_digest_is_trusted_dir(const char *digest) { if (!trusted_dir_servers) return 0; if (get_options()->AuthoritativeDir && router_digest_is_me(digest)) return 1; SMARTLIST_FOREACH(trusted_dir_servers, trusted_dir_server_t *, ent, if (!memcmp(digest, ent->digest, DIGEST_LEN)) return 1); return 0; } /** Return the router in our routerlist whose hexadecimal key digest * is hexdigest. Return NULL if no such router is known. */ routerinfo_t * router_get_by_hexdigest(const char *hexdigest) { char digest[DIGEST_LEN]; tor_assert(hexdigest); if (!routerlist) return NULL; if (hexdigest[0]=='$') ++hexdigest; if (strlen(hexdigest) != HEX_DIGEST_LEN || base16_decode(digest,DIGEST_LEN,hexdigest,HEX_DIGEST_LEN) < 0) return NULL; return router_get_by_digest(digest); } /** Return the router in our routerlist whose 20-byte key digest * is digest. Return NULL if no such router is known. */ routerinfo_t * router_get_by_digest(const char *digest) { tor_assert(digest); if (!routerlist) return NULL; // routerlist_assert_ok(routerlist); return digestmap_get(routerlist->identity_map, digest); } /** Return the router in our routerlist whose 20-byte descriptor * is digest. Return NULL if no such router is known. */ signed_descriptor_t * router_get_by_descriptor_digest(const char *digest) { tor_assert(digest); if (!routerlist) return NULL; return digestmap_get(routerlist->desc_digest_map, digest); } const char * signed_descriptor_get_body(signed_descriptor_t *desc) { return desc->signed_descriptor_body; } /** Return the current list of all known routers. */ routerlist_t * router_get_routerlist(void) { if (!routerlist) { routerlist = tor_malloc_zero(sizeof(routerlist_t)); routerlist->routers = smartlist_create(); routerlist->old_routers = smartlist_create(); routerlist->identity_map = digestmap_new(); routerlist->desc_digest_map = digestmap_new(); } return routerlist; } /** Free all storage held by router. */ void routerinfo_free(routerinfo_t *router) { if (!router) return; tor_free(router->cache_info.signed_descriptor_body); tor_free(router->address); tor_free(router->nickname); tor_free(router->platform); tor_free(router->contact_info); if (router->onion_pkey) crypto_free_pk_env(router->onion_pkey); if (router->identity_pkey) crypto_free_pk_env(router->identity_pkey); if (router->declared_family) { SMARTLIST_FOREACH(router->declared_family, char *, s, tor_free(s)); smartlist_free(router->declared_family); } addr_policy_free(router->exit_policy); tor_free(router); } /** Release storage held by sd. */ static void signed_descriptor_free(signed_descriptor_t *sd) { tor_free(sd->signed_descriptor_body); tor_free(sd); } /** Extract a signed_descriptor_t from a routerinfo, and free the routerinfo. */ static signed_descriptor_t * signed_descriptor_from_routerinfo(routerinfo_t *ri) { signed_descriptor_t *sd = tor_malloc_zero(sizeof(signed_descriptor_t)); memcpy(sd, &(ri->cache_info), sizeof(signed_descriptor_t)); ri->cache_info.signed_descriptor_body = NULL; routerinfo_free(ri); return sd; } /** Free all storage held by a routerlist rl */ void routerlist_free(routerlist_t *rl) { tor_assert(rl); digestmap_free(rl->identity_map, NULL); digestmap_free(rl->desc_digest_map, NULL); SMARTLIST_FOREACH(rl->routers, routerinfo_t *, r, routerinfo_free(r)); SMARTLIST_FOREACH(rl->old_routers, signed_descriptor_t *, sd, signed_descriptor_free(sd)); smartlist_free(rl->routers); smartlist_free(rl->old_routers); tor_free(rl); } void dump_routerlist_mem_usage(int severity) { uint64_t livedescs = 0; uint64_t olddescs = 0; if (!routerlist) return; SMARTLIST_FOREACH(routerlist->routers, routerinfo_t *, r, livedescs += r->cache_info.signed_descriptor_len); SMARTLIST_FOREACH(routerlist->old_routers, signed_descriptor_t *, sd, olddescs += sd->signed_descriptor_len); log(severity, LD_GENERAL, "In %d live descriptors: "U64_FORMAT" bytes. " "In %d old descriptors: "U64_FORMAT" bytes.", smartlist_len(routerlist->routers), U64_PRINTF_ARG(livedescs), smartlist_len(routerlist->old_routers), U64_PRINTF_ARG(olddescs)); } /** Return the greatest number of routerdescs we'll hold for any given router. */ static int max_descriptors_per_router(void) { int n_authorities = 0; if (trusted_dir_servers) n_authorities = smartlist_len(trusted_dir_servers); return (n_authorities < 5) ? 5 : n_authorities; } /** Return non-zero if we have a lot of extra descriptors in our * routerlist, and should get rid of some of them. Else return 0. * * We should be careful to not return true too eagerly, since we * could churn. By using "+1" below, we make sure this function * only returns true at most every smartlist_len(rl-\>routers) * new descriptors. */ static INLINE int routerlist_is_overfull(routerlist_t *rl) { return smartlist_len(rl->old_routers) > smartlist_len(rl->routers)*(max_descriptors_per_router()+1); } static INLINE int _routerlist_find_elt(smartlist_t *sl, void *ri, int idx) { if (idx < 0 || smartlist_get(sl, idx) != ri) { idx = -1; SMARTLIST_FOREACH(sl, routerinfo_t *, r, if (r == ri) { idx = r_sl_idx; break; }); } return idx; } /** Insert an item ri into the routerlist rl, updating indices * as needed. */ static void routerlist_insert(routerlist_t *rl, routerinfo_t *ri) { digestmap_set(rl->identity_map, ri->cache_info.identity_digest, ri); digestmap_set(rl->desc_digest_map, ri->cache_info.signed_descriptor_digest, &(ri->cache_info)); smartlist_add(rl->routers, ri); // routerlist_assert_ok(rl); } static void routerlist_insert_old(routerlist_t *rl, routerinfo_t *ri) { if (get_options()->DirPort && !digestmap_get(rl->desc_digest_map, ri->cache_info.signed_descriptor_digest)) { signed_descriptor_t *sd = signed_descriptor_from_routerinfo(ri); digestmap_set(rl->desc_digest_map, sd->signed_descriptor_digest, sd); smartlist_add(rl->old_routers, sd); } else { routerinfo_free(ri); } // routerlist_assert_ok(rl); } /** Remove an item ri from the routerlist rl, updating indices * as needed. If idx is nonnegative and smartlist_get(rl->routers, * idx) == ri, we don't need to do a linear search over the list to decide * which to remove. We fill the gap in rl->routers with a later element in * the list, if any exists. ri is freed. */ void routerlist_remove(routerlist_t *rl, routerinfo_t *ri, int idx, int make_old) { routerinfo_t *ri_tmp; idx = _routerlist_find_elt(rl->routers, ri, idx); if (idx < 0) return; smartlist_del(rl->routers, idx); ri_tmp = digestmap_remove(rl->identity_map, ri->cache_info.identity_digest); tor_assert(ri_tmp == ri); if (make_old && get_options()->DirPort) { signed_descriptor_t *sd; sd = signed_descriptor_from_routerinfo(ri); smartlist_add(rl->old_routers, sd); digestmap_set(rl->desc_digest_map, sd->signed_descriptor_digest, sd); } else { ri_tmp = digestmap_remove(rl->desc_digest_map, ri->cache_info.signed_descriptor_digest); tor_assert(ri_tmp == ri); router_bytes_dropped += ri->cache_info.signed_descriptor_len; routerinfo_free(ri); } // routerlist_assert_ok(rl); } static void routerlist_remove_old(routerlist_t *rl, signed_descriptor_t *sd, int idx) { signed_descriptor_t *sd_tmp; idx = _routerlist_find_elt(rl->old_routers, sd, idx); if (idx < 0) return; smartlist_del(rl->old_routers, idx); sd_tmp = digestmap_remove(rl->desc_digest_map, sd->signed_descriptor_digest); tor_assert(sd_tmp == sd); router_bytes_dropped += sd->signed_descriptor_len; signed_descriptor_free(sd); // routerlist_assert_ok(rl); } /** Remove ri_old from the routerlist rl, and replace it with * ri_new, updating all index info. If idx is nonnegative and * smartlist_get(rl->routers, idx) == ri, we don't need to do a linear * search over the list to decide which to remove. We put ri_new in the same * index as ri_old, if possible. ri is freed as appropriate. */ static void routerlist_replace(routerlist_t *rl, routerinfo_t *ri_old, routerinfo_t *ri_new, int idx, int make_old) { tor_assert(ri_old != ri_new); idx = _routerlist_find_elt(rl->routers, ri_old, idx); if (idx >= 0) { smartlist_set(rl->routers, idx, ri_new); } else { log_warn(LD_BUG, "Appending entry from routerlist_replace."); routerlist_insert(rl, ri_new); return; } if (memcmp(ri_old->cache_info.identity_digest, ri_new->cache_info.identity_digest, DIGEST_LEN)) { /* digests don't match; digestmap_set won't replace */ digestmap_remove(rl->identity_map, ri_old->cache_info.identity_digest); } digestmap_set(rl->identity_map, ri_new->cache_info.identity_digest, ri_new); digestmap_set(rl->desc_digest_map, ri_new->cache_info.signed_descriptor_digest, &(ri_new->cache_info)); if (make_old && get_options()->DirPort) { signed_descriptor_t *sd = signed_descriptor_from_routerinfo(ri_old); smartlist_add(rl->old_routers, sd); digestmap_set(rl->desc_digest_map, sd->signed_descriptor_digest, sd); } else { if (memcmp(ri_old->cache_info.signed_descriptor_digest, ri_new->cache_info.signed_descriptor_digest, DIGEST_LEN)) { /* digests don't match; digestmap_set didn't replace */ digestmap_remove(rl->desc_digest_map, ri_old->cache_info.signed_descriptor_digest); } routerinfo_free(ri_old); } // routerlist_assert_ok(rl); } /** Free all memory held by the routerlist module. */ void routerlist_free_all(void) { if (routerlist) routerlist_free(routerlist); routerlist = NULL; if (warned_nicknames) { SMARTLIST_FOREACH(warned_nicknames, char *, cp, tor_free(cp)); smartlist_free(warned_nicknames); warned_nicknames = NULL; } if (warned_conflicts) { SMARTLIST_FOREACH(warned_conflicts, char *, cp, tor_free(cp)); smartlist_free(warned_conflicts); warned_conflicts = NULL; } if (trusted_dir_servers) { SMARTLIST_FOREACH(trusted_dir_servers, trusted_dir_server_t *, ds, trusted_dir_server_free(ds)); smartlist_free(trusted_dir_servers); trusted_dir_servers = NULL; } if (networkstatus_list) { SMARTLIST_FOREACH(networkstatus_list, networkstatus_t *, ns, networkstatus_free(ns)); smartlist_free(networkstatus_list); networkstatus_list = NULL; } if (routerstatus_list) { SMARTLIST_FOREACH(routerstatus_list, local_routerstatus_t *, rs, local_routerstatus_free(rs)); smartlist_free(routerstatus_list); routerstatus_list = NULL; } } /** Free all storage held by the routerstatus object rs. */ void routerstatus_free(routerstatus_t *rs) { tor_free(rs); } /** Free all storage held by the local_routerstatus object rs. */ static void local_routerstatus_free(local_routerstatus_t *rs) { tor_free(rs); } /** Free all storage held by the networkstatus object ns. */ void networkstatus_free(networkstatus_t *ns) { tor_free(ns->source_address); tor_free(ns->contact); if (ns->signing_key) crypto_free_pk_env(ns->signing_key); tor_free(ns->client_versions); tor_free(ns->server_versions); if (ns->entries) { SMARTLIST_FOREACH(ns->entries, routerstatus_t *, rs, routerstatus_free(rs)); smartlist_free(ns->entries); } tor_free(ns); } /** Forget that we have issued any router-related warnings, so that we'll * warn again if we see the same errors. */ void routerlist_reset_warnings(void) { if (!warned_nicknames) warned_nicknames = smartlist_create(); SMARTLIST_FOREACH(warned_nicknames, char *, cp, tor_free(cp)); smartlist_clear(warned_nicknames); /* now the list is empty. */ if (!warned_conflicts) warned_conflicts = smartlist_create(); SMARTLIST_FOREACH(warned_conflicts, char *, cp, tor_free(cp)); smartlist_clear(warned_conflicts); /* now the list is empty. */ if (!routerstatus_list) routerstatus_list = smartlist_create(); SMARTLIST_FOREACH(routerstatus_list, local_routerstatus_t *, rs, rs->name_lookup_warned = 0); have_warned_about_invalid_status = 0; have_warned_about_old_version = 0; have_warned_about_new_version = 0; } /** Mark the router with ID digest as running or non-running * in our routerlist. */ void router_set_status(const char *digest, int up) { routerinfo_t *router; local_routerstatus_t *status; tor_assert(digest); SMARTLIST_FOREACH(trusted_dir_servers, trusted_dir_server_t *, d, if (!memcmp(d->digest, digest, DIGEST_LEN)) d->is_running = up); router = router_get_by_digest(digest); if (router) { log_debug(LD_DIR,"Marking router '%s' as %s.", router->nickname, up ? "up" : "down"); if (!up && router_is_me(router) && !we_are_hibernating()) log_warn(LD_NET, "We just marked ourself as down. Are your external " "addresses reachable?"); router->is_running = up; } status = router_get_combined_status_by_digest(digest); if (status) { status->status.is_running = up; } } /** Add router to the routerlist, if we don't already have it. Replace * older entries (if any) with the same key. Note: Callers should not hold * their pointers to router if this function fails; router * will either be inserted into the routerlist or freed. * * Returns >= 0 if the router was added; less than 0 if it was not. * * If we're returning non-zero, then assign to *msg a static string * describing the reason for not liking the routerinfo. * * If the return value is less than -1, there was a problem with the * routerinfo. If the return value is equal to -1, then the routerinfo was * fine, but out-of-date. If the return value is equal to 1, the * routerinfo was accepted, but we should notify the generator of the * descriptor using the message *msg. * * If from_cache, this descriptor came from our disk cache. If * from_fetch, we received it in response to a request we made. * (If both are false, that means it was uploaded to us as an auth dir * server or via the controller.) * * This function should be called *after* * routers_update_status_from_networkstatus; subsequently, you should call * router_rebuild_store and control_event_descriptors_changed. */ int router_add_to_routerlist(routerinfo_t *router, const char **msg, int from_cache, int from_fetch) { int i; const char *id_digest; int authdir = get_options()->AuthoritativeDir; int authdir_believes_valid = 0; tor_assert(msg); if (!routerlist) router_get_routerlist(); if (!networkstatus_list) networkstatus_list = smartlist_create(); id_digest = router->cache_info.identity_digest; /* Make sure that we haven't already got this exact descriptor. */ if (digestmap_get(routerlist->desc_digest_map, router->cache_info.signed_descriptor_digest)) { log_info(LD_DIR, "Dropping descriptor that we already have for router '%s'", router->nickname); *msg = "Router descriptor was not new."; routerinfo_free(router); return -1; } if (routerlist_is_overfull(routerlist)) routerlist_remove_old_routers(); if (authdir) { if (authdir_wants_to_reject_router(router, msg, !from_cache && !from_fetch)) { tor_assert(*msg); routerinfo_free(router); return -2; } authdir_believes_valid = router->is_valid; } else if (from_fetch) { /* Only check the descriptor digest against the network statuses when * we are receiving in response to a fetch. */ if (!signed_desc_digest_is_recognized(&router->cache_info)) { log_warn(LD_DIR, "Dropping unrecognized descriptor for router '%s'", router->nickname); *msg = "Router descriptor is not referenced by any network-status."; routerinfo_free(router); return -1; } } /* We no longer need a router with this descriptor digest. */ SMARTLIST_FOREACH(networkstatus_list, networkstatus_t *, ns, { routerstatus_t *rs = networkstatus_find_entry(ns, router->cache_info.identity_digest); if (rs && !memcmp(rs->descriptor_digest, router->cache_info.signed_descriptor_digest, DIGEST_LEN)) rs->need_to_mirror = 0; }); /* Probably, there's no way to actually pass this function our own * descriptor, but in case there is, don't replace our own descriptor. */ if (router_is_me(router)) { routerinfo_free(router); return 0; } /* If we have a router with this name, and the identity key is the same, * choose the newer one. If the identity key has changed, and one of the * routers is named, drop the unnamed ones. (If more than one are named, * drop the old ones.) */ for (i = 0; i < smartlist_len(routerlist->routers); ++i) { routerinfo_t *old_router = smartlist_get(routerlist->routers, i); if (!crypto_pk_cmp_keys(router->identity_pkey,old_router->identity_pkey)) { if (router->cache_info.published_on <= old_router->cache_info.published_on) { /* Same key, but old */ log_debug(LD_DIR, "Skipping not-new descriptor for router '%s'", router->nickname); /* Only journal this desc if we'll be serving it. */ if (!from_cache && get_options()->DirPort) router_append_to_journal(&router->cache_info); routerlist_insert_old(routerlist, router); *msg = "Router descriptor was not new."; return -1; } else { /* Same key, new. */ int unreachable = 0; log_debug(LD_DIR, "Replacing entry for router '%s/%s' [%s]", router->nickname, old_router->nickname, hex_str(id_digest,DIGEST_LEN)); if (router->addr == old_router->addr && router->or_port == old_router->or_port) { /* these carry over when the address and orport are unchanged.*/ router->last_reachable = old_router->last_reachable; router->testing_since = old_router->testing_since; router->num_unreachable_notifications = old_router->num_unreachable_notifications; } if (authdir && !from_cache && !from_fetch && router_have_minimum_dir_info() && dirserv_thinks_router_is_blatantly_unreachable(router, time(NULL))) { if (router->num_unreachable_notifications >= 3) { unreachable = 1; log_notice(LD_DIR, "Notifying server '%s' that it's unreachable. " "(ContactInfo '%s', platform '%s').", router->nickname, router->contact_info ? router->contact_info : "", router->platform ? router->platform : ""); } else { log_info(LD_DIR,"'%s' may be unreachable -- the %d previous " "descriptors were thought to be unreachable.", router->nickname, router->num_unreachable_notifications); router->num_unreachable_notifications++; } } routerlist_replace(routerlist, old_router, router, i, 1); if (!from_cache) { router_append_to_journal(&router->cache_info); } directory_set_dirty(); *msg = unreachable ? "Dirserver believes your ORPort is unreachable" : authdir_believes_valid ? "Valid server updated" : ("Invalid server updated. (This dirserver is marking your " "server as unapproved.)"); return unreachable ? 1 : 0; } } else if (!strcasecmp(router->nickname, old_router->nickname)) { /* nicknames match, keys don't. */ if (router->is_named) { /* The new named router replaces the old one; remove the * old one. And carry on to the end of the list, in case * there are more old unnamed routers with this nickname. */ /* mark-for-close connections using the old key, so we can * make new ones with the new key. */ connection_t *conn; while ((conn = connection_or_get_by_identity_digest( old_router->cache_info.identity_digest))) { log_info(LD_DIR,"Closing conn to router '%s'; there is now a named " "router with that name.", old_router->nickname); connection_mark_for_close(conn); } routerlist_remove(routerlist, old_router, i--, 0); } else if (old_router->is_named) { /* Can't replace a named router with an unnamed one. */ log_debug(LD_DIR, "Skipping unnamed entry for named router '%s'", router->nickname); routerinfo_free(router); *msg = "Already have named router with same nickname and different key."; return -2; } } } /* We haven't seen a router with this name before. Add it to the end of * the list. */ routerlist_insert(routerlist, router); if (!from_cache) router_append_to_journal(&router->cache_info); directory_set_dirty(); return 0; } static int _compare_old_routers_by_identity(const void **_a, const void **_b) { int i; const signed_descriptor_t *r1 = *_a, *r2 = *_b; if ((i = memcmp(r1->identity_digest, r2->identity_digest, DIGEST_LEN))) return i; return r1->published_on - r2->published_on; } struct duration_idx_t { int duration; int idx; int old; }; static int _compare_duration_idx(const void *_d1, const void *_d2) { const struct duration_idx_t *d1 = _d1; const struct duration_idx_t *d2 = _d2; return d1->duration - d2->duration; } /** The range lo through hi inclusive of routerlist->old_routers * must contain routerinfo_t with the same identity and with publication time * in ascending order. Remove members from this range until there are no more * than max_descriptors_per_router() remaining. Start by removing the oldest * members from before cutoff, then remove members which were current * for the lowest amount of time. The order of members of old_routers at * indices lo or higher may be changed. */ static void routerlist_remove_old_cached_routers_with_id(time_t cutoff, int lo, int hi, digestmap_t *retain) { int i, n = hi-lo+1, n_extra; int n_rmv = 0; struct duration_idx_t *lifespans; uint8_t *rmv, *must_keep; smartlist_t *lst = routerlist->old_routers; #if 1 const char *ident; tor_assert(hi < smartlist_len(lst)); tor_assert(lo <= hi); ident = ((signed_descriptor_t*)smartlist_get(lst, lo))->identity_digest; for (i = lo+1; i <= hi; ++i) { signed_descriptor_t *r = smartlist_get(lst, i); tor_assert(!memcmp(ident, r->identity_digest, DIGEST_LEN)); } #endif /* Check whether we need to do anything at all. */ n_extra = n - max_descriptors_per_router(); if (n_extra <= 0) return; lifespans = tor_malloc_zero(sizeof(struct duration_idx_t)*n); rmv = tor_malloc_zero(sizeof(uint8_t)*n); must_keep = tor_malloc_zero(sizeof(uint8_t)*n); /* Set lifespans to contain the lifespan and index of each server. */ /* Set rmv[i-lo]=1 if we're going to remove a server for being too old. */ for (i = lo; i <= hi; ++i) { signed_descriptor_t *r = smartlist_get(lst, i); signed_descriptor_t *r_next; lifespans[i-lo].idx = i; if (retain && digestmap_get(retain, r->signed_descriptor_digest)) { must_keep[i-lo] = 1; } if (i < hi) { r_next = smartlist_get(lst, i+1); tor_assert(r->published_on <= r_next->published_on); lifespans[i-lo].duration = (r_next->published_on - r->published_on); } else { r_next = NULL; lifespans[i-lo].duration = INT_MAX; } if (!must_keep[i-lo] && r->published_on < cutoff && n_rmv < n_extra) { ++n_rmv; lifespans[i-lo].old = 1; rmv[i-lo] = 1; } } if (n_rmv < n_extra) { /** * We aren't removing enough servers for being old. Sort lifespans by * the duration of liveness, and remove the ones we're not already going to * remove based on how long they were alive. **/ qsort(lifespans, n, sizeof(struct duration_idx_t), _compare_duration_idx); for (i = 0; i < n && n_rmv < n_extra; ++i) { if (!must_keep[lifespans[i].idx-lo] && !lifespans[i].old) { rmv[lifespans[i].idx-lo] = 1; ++n_rmv; } } } for (i = hi; i >= lo; --i) { if (rmv[i-lo]) routerlist_remove_old(routerlist, smartlist_get(lst, i), i); } tor_free(must_keep); tor_free(rmv); tor_free(lifespans); } /** Deactivate any routers from the routerlist that are more than * ROUTER_MAX_AGE seconds old; remove old routers from the list of * cached routers if we have too many. */ void routerlist_remove_old_routers(void) { int i, hi=-1; const char *cur_id = NULL; time_t now = time(NULL); time_t cutoff; routerinfo_t *router; signed_descriptor_t *sd; digestmap_t *retain; or_options_t *options = get_options(); if (!routerlist || !networkstatus_list) return; retain = digestmap_new(); cutoff = now - OLD_ROUTER_DESC_MAX_AGE; if (server_mode(options) && options->DirPort) { SMARTLIST_FOREACH(networkstatus_list, networkstatus_t *, ns, { SMARTLIST_FOREACH(ns->entries, routerstatus_t *, rs, if (rs->published_on >= cutoff) digestmap_set(retain, rs->descriptor_digest, (void*)1)); }); } cutoff = now - ROUTER_MAX_AGE; /* Remove too-old members of routerlist->routers. */ for (i = 0; i < smartlist_len(routerlist->routers); ++i) { router = smartlist_get(routerlist->routers, i); if (router->cache_info.published_on <= cutoff && !digestmap_get(retain, router->cache_info.signed_descriptor_digest)) { /* Too old. Remove it. */ log_info(LD_DIR, "Forgetting obsolete (too old) routerinfo for router '%s'", router->nickname); routerlist_remove(routerlist, router, i--, 1); } } /* Remove far-too-old members of routerlist->old_routers. */ cutoff = now - OLD_ROUTER_DESC_MAX_AGE; for (i = 0; i < smartlist_len(routerlist->old_routers); ++i) { sd = smartlist_get(routerlist->old_routers, i); if (sd->published_on <= cutoff && !digestmap_get(retain, sd->signed_descriptor_digest)) { /* Too old. Remove it. */ routerlist_remove_old(routerlist, sd, i--); } } /* Now we're looking at routerlist->old_routers for extraneous * members. (We'd keep all the members if we could, but we'd like to save * space.) First, check whether we have too many router descriptors, total. * We're okay with having too many for some given router, so long as the * total number doesn't approach max_descriptors_per_router()*len(router). */ if (smartlist_len(routerlist->old_routers) < smartlist_len(routerlist->routers) * (max_descriptors_per_router() - 1)) goto done; smartlist_sort(routerlist->old_routers, _compare_old_routers_by_identity); /* Iterate through the list from back to front, so when we remove descriptors * we don't mess up groups we haven't gotten to. */ for (i = smartlist_len(routerlist->old_routers)-1; i >= 0; --i) { signed_descriptor_t *r = smartlist_get(routerlist->old_routers, i); if (!cur_id) { cur_id = r->identity_digest; hi = i; } if (memcmp(cur_id, r->identity_digest, DIGEST_LEN)) { routerlist_remove_old_cached_routers_with_id(cutoff, i+1, hi, retain); cur_id = r->identity_digest; hi = i; } } if (hi>=0) routerlist_remove_old_cached_routers_with_id(cutoff, 0, hi, retain); routerlist_assert_ok(routerlist); done: digestmap_free(retain, NULL); } /** * Code to parse a single router descriptor and insert it into the * routerlist. Return -1 if the descriptor was ill-formed; 0 if the * descriptor was well-formed but could not be added; and 1 if the * descriptor was added. * * If we don't add it and msg is not NULL, then assign to * *msg a static string describing the reason for refusing the * descriptor. * * This is used only by the controller. */ int router_load_single_router(const char *s, uint8_t purpose, const char **msg) { routerinfo_t *ri; int r; smartlist_t *lst; tor_assert(msg); *msg = NULL; if (!(ri = router_parse_entry_from_string(s, NULL))) { log_warn(LD_DIR, "Error parsing router descriptor; dropping."); *msg = "Couldn't parse router descriptor."; return -1; } ri->purpose = purpose; if (router_is_me(ri)) { log_warn(LD_DIR, "Router's identity key matches mine; dropping."); *msg = "Router's identity key matches mine."; routerinfo_free(ri); return 0; } lst = smartlist_create(); smartlist_add(lst, ri); routers_update_status_from_networkstatus(lst, 0); if ((r=router_add_to_routerlist(ri, msg, 0, 0))<0) { /* we've already assigned to *msg now, and ri is already freed */ tor_assert(*msg); if (r < -1) log_warn(LD_DIR, "Couldn't add router to list: %s Dropping.", *msg); smartlist_free(lst); return 0; } else { control_event_descriptors_changed(lst); smartlist_free(lst); log_debug(LD_DIR, "Added router to list"); return 1; } } /** Given a string s containing some routerdescs, parse it and put the * routers into our directory. If from_cache is false, the routers * are in response to a query to the network: cache them. * * If requested_fingerprints is provided, it must contain a list of * uppercased identity fingerprints. Do not update any router whose * fingerprint is not on the list; after updating a router, remove its * fingerprint from the list. */ void router_load_routers_from_string(const char *s, int from_cache, smartlist_t *requested_fingerprints) { smartlist_t *routers = smartlist_create(), *changed = smartlist_create(); char fp[HEX_DIGEST_LEN+1]; const char *msg; router_parse_list_from_string(&s, routers); routers_update_status_from_networkstatus(routers, !from_cache); log_info(LD_DIR, "%d elements to add", smartlist_len(routers)); SMARTLIST_FOREACH(routers, routerinfo_t *, ri, { base16_encode(fp, sizeof(fp), ri->cache_info.signed_descriptor_digest, DIGEST_LEN); if (requested_fingerprints) { if (smartlist_string_isin(requested_fingerprints, fp)) { smartlist_string_remove(requested_fingerprints, fp); } else { char *requested = smartlist_join_strings(requested_fingerprints," ",0,NULL); log_warn(LD_DIR, "We received a router descriptor with a fingerprint (%s) " "that we never requested. (We asked for: %s.) Dropping.", fp, requested); tor_free(requested); routerinfo_free(ri); continue; } } if (router_add_to_routerlist(ri, &msg, from_cache, !from_cache) >= 0) smartlist_add(changed, ri); }); if (smartlist_len(changed)) control_event_descriptors_changed(changed); routerlist_assert_ok(routerlist); router_rebuild_store(0); smartlist_free(routers); smartlist_free(changed); } /** Helper: return a newly allocated string containing the name of the filename * where we plan to cache ns. */ static char * networkstatus_get_cache_filename(const networkstatus_t *ns) { const char *datadir = get_options()->DataDirectory; size_t len = strlen(datadir)+64; char fp[HEX_DIGEST_LEN+1]; char *fn = tor_malloc(len+1); base16_encode(fp, HEX_DIGEST_LEN+1, ns->identity_digest, DIGEST_LEN); tor_snprintf(fn, len, "%s/cached-status/%s",datadir,fp); return fn; } /** Helper for smartlist_sort: Compare two networkstatus objects by * publication date. */ static int _compare_networkstatus_published_on(const void **_a, const void **_b) { const networkstatus_t *a = *_a, *b = *_b; if (a->published_on < b->published_on) return -1; else if (a->published_on > b->published_on) return 1; else return 0; } /** Add the parsed neworkstatus in ns (with original document in * s to the disk cache (and the in-memory directory server cache) as * appropriate. */ static int add_networkstatus_to_cache(const char *s, networkstatus_source_t source, networkstatus_t *ns) { if (source != NS_FROM_CACHE) { char *fn = networkstatus_get_cache_filename(ns); if (write_str_to_file(fn, s, 0)<0) { log_notice(LD_FS, "Couldn't write cached network status to \"%s\"", fn); } tor_free(fn); } if (get_options()->DirPort) dirserv_set_cached_networkstatus_v2(s, ns->identity_digest, ns->published_on); return 0; } /** How far in the future do we allow a network-status to get before removing * it? (seconds) */ #define NETWORKSTATUS_ALLOW_SKEW (24*60*60) /** Given a string s containing a network status that we received at * arrived_at from source, try to parse it, see if we want to * store it, and put it into our cache as necessary. * * If source is NS_FROM_DIR or NS_FROM_CACHE, do not replace our * own networkstatus_t (if we're a directory server). * * If source is NS_FROM_CACHE, do not write our networkstatus_t to the * cache. * * If requested_fingerprints is provided, it must contain a list of * uppercased identity fingerprints. Do not update any networkstatus whose * fingerprint is not on the list; after updating a networkstatus, remove its * fingerprint from the list. * * Return 0 on success, -1 on failure. * * Callers should make sure that routers_update_all_from_networkstatus() is * invoked after this function succeeds. */ int router_set_networkstatus(const char *s, time_t arrived_at, networkstatus_source_t source, smartlist_t *requested_fingerprints) { networkstatus_t *ns; int i, found; time_t now; int skewed = 0; trusted_dir_server_t *trusted_dir = NULL; const char *source_desc = NULL; char fp[HEX_DIGEST_LEN+1]; char published[ISO_TIME_LEN+1]; ns = networkstatus_parse_from_string(s); if (!ns) { log_warn(LD_DIR, "Couldn't parse network status."); return -1; } base16_encode(fp, HEX_DIGEST_LEN+1, ns->identity_digest, DIGEST_LEN); if (!(trusted_dir = router_get_trusteddirserver_by_digest(ns->identity_digest))) { log_info(LD_DIR, "Network status was signed, but not by an authoritative " "directory we recognize."); if (!get_options()->DirPort) { networkstatus_free(ns); return 0; } source_desc = fp; } else { source_desc = trusted_dir->description; } now = time(NULL); if (arrived_at > now) arrived_at = now; ns->received_on = arrived_at; format_iso_time(published, ns->published_on); if (ns->published_on > now + NETWORKSTATUS_ALLOW_SKEW) { log_warn(LD_GENERAL, "Network status from %s was published in the future " "(%s GMT). Somebody is skewed here: check your clock. " "Not caching.", source_desc, published); skewed = 1; } if (!networkstatus_list) networkstatus_list = smartlist_create(); if (source == NS_FROM_DIR && router_digest_is_me(ns->identity_digest)) { /* Don't replace our own networkstatus when we get it from somebody else.*/ networkstatus_free(ns); return 0; } if (requested_fingerprints) { if (smartlist_string_isin(requested_fingerprints, fp)) { smartlist_string_remove(requested_fingerprints, fp); } else { char *requested = smartlist_join_strings(requested_fingerprints," ",0,NULL); log_warn(LD_DIR, "We received a network status with a fingerprint (%s) that we " "never requested. (We asked for: %s.) Dropping.", fp, requested); tor_free(requested); return 0; } } if (!trusted_dir) { if (!skewed && get_options()->DirPort) { /* We got a non-trusted networkstatus, and we're a directory cache. * This means that we asked an authority, and it told us about another * authority we didn't recognize. */ add_networkstatus_to_cache(s, source, ns); networkstatus_free(ns); } return 0; } if (source != NS_FROM_CACHE && trusted_dir) trusted_dir->n_networkstatus_failures = 0; found = 0; for (i=0; i < smartlist_len(networkstatus_list); ++i) { networkstatus_t *old_ns = smartlist_get(networkstatus_list, i); if (!memcmp(old_ns->identity_digest, ns->identity_digest, DIGEST_LEN)) { if (!memcmp(old_ns->networkstatus_digest, ns->networkstatus_digest, DIGEST_LEN)) { /* Same one we had before. */ networkstatus_free(ns); log_info(LD_DIR, "Not replacing network-status from %s (published %s); " "we already have it.", trusted_dir->description, published); if (old_ns->received_on < arrived_at) { if (source != NS_FROM_CACHE) { char *fn = networkstatus_get_cache_filename(old_ns); /* We use mtime to tell when it arrived, so update that. */ touch_file(fn); tor_free(fn); } old_ns->received_on = arrived_at; } return 0; } else if (old_ns->published_on >= ns->published_on) { char old_published[ISO_TIME_LEN+1]; format_iso_time(old_published, old_ns->published_on); log_info(LD_DIR, "Not replacing network-status from %s (published %s);" " we have a newer one (published %s) for this authority.", trusted_dir->description, published, old_published); networkstatus_free(ns); return 0; } else { networkstatus_free(old_ns); smartlist_set(networkstatus_list, i, ns); found = 1; break; } } } if (!found) smartlist_add(networkstatus_list, ns); SMARTLIST_FOREACH(ns->entries, routerstatus_t *, rs, { if (!router_get_by_descriptor_digest(rs->descriptor_digest)) rs->need_to_mirror = 1; }); log_info(LD_DIR, "Setting networkstatus %s %s (published %s)", source == NS_FROM_CACHE?"cached from": (source==NS_FROM_DIR?"downloaded from":"generated for"), trusted_dir->description, published); networkstatus_list_has_changed = 1; smartlist_sort(networkstatus_list, _compare_networkstatus_published_on); if (!skewed) add_networkstatus_to_cache(s, source, ns); networkstatus_list_update_recent(now); return 0; } /** How old do we allow a network-status to get before removing it * completely? */ #define MAX_NETWORKSTATUS_AGE (10*24*60*60) /** Remove all very-old network_status_t objects from memory and from the * disk cache. */ void networkstatus_list_clean(time_t now) { int i; if (!networkstatus_list) return; for (i = 0; i < smartlist_len(networkstatus_list); ++i) { networkstatus_t *ns = smartlist_get(networkstatus_list, i); char *fname = NULL;; if (ns->published_on + MAX_NETWORKSTATUS_AGE > now) continue; /* Okay, this one is too old. Remove it from the list, and delete it * from the cache. */ smartlist_del(networkstatus_list, i--); fname = networkstatus_get_cache_filename(ns); if (file_status(fname) == FN_FILE) { log_info(LD_DIR, "Removing too-old networkstatus in %s", fname); unlink(fname); } tor_free(fname); if (get_options()->DirPort) { dirserv_set_cached_networkstatus_v2(NULL, ns->identity_digest, 0); } networkstatus_free(ns); } } /** Helper for bsearching a list of routerstatus_t pointers.*/ static int _compare_digest_to_routerstatus_entry(const void *_key, const void **_member) { const char *key = _key; const routerstatus_t *rs = *_member; return memcmp(key, rs->identity_digest, DIGEST_LEN); } /** Return the entry in ns for the identity digest digest, or * NULL if none was found. */ static routerstatus_t * networkstatus_find_entry(networkstatus_t *ns, const char *digest) { return smartlist_bsearch(ns->entries, digest, _compare_digest_to_routerstatus_entry); } /** Return the consensus view of the status of the router whose digest is * digest, or NULL if we don't know about any such router. */ local_routerstatus_t * router_get_combined_status_by_digest(const char *digest) { if (!routerstatus_list) return NULL; return smartlist_bsearch(routerstatus_list, digest, _compare_digest_to_routerstatus_entry); } /** Return true iff any networkstatus includes a descriptor whose digest * is that of desc. */ static int signed_desc_digest_is_recognized(signed_descriptor_t *desc) { routerstatus_t *rs; if (!networkstatus_list) return 0; SMARTLIST_FOREACH(networkstatus_list, networkstatus_t *, ns, { if (!(rs = networkstatus_find_entry(ns, desc->identity_digest))) continue; if (!memcmp(rs->descriptor_digest, desc->signed_descriptor_digest, DIGEST_LEN)) return 1; }); return 0; } /** How frequently do directory authorities re-download fresh networkstatus * documents? */ #define AUTHORITY_NS_CACHE_INTERVAL (5*60) /** How frequently do non-authority directory caches re-download fresh * networkstatus documents? */ #define NONAUTHORITY_NS_CACHE_INTERVAL (15*60) /** We are a directory server, and so cache network_status documents. * Initiate downloads as needed to update them. For authorities, this means * asking each trusted directory for its network-status. For caches, this * means asking a random authority for all network-statuses. */ static void update_networkstatus_cache_downloads(time_t now) { int authority = authdir_mode(get_options()); int interval = authority ? AUTHORITY_NS_CACHE_INTERVAL : NONAUTHORITY_NS_CACHE_INTERVAL; if (last_networkstatus_download_attempted + interval >= now) return; if (!trusted_dir_servers) return; last_networkstatus_download_attempted = now; if (authority) { /* An authority launches a separate connection for everybody. */ SMARTLIST_FOREACH(trusted_dir_servers, trusted_dir_server_t *, ds, { char resource[HEX_DIGEST_LEN+6]; /* fp/hexdigit.z\0 */ if (router_digest_is_me(ds->digest)) continue; if (connection_get_by_type_addr_port_purpose( CONN_TYPE_DIR, ds->addr, ds->dir_port, DIR_PURPOSE_FETCH_NETWORKSTATUS)) { /* We are already fetching this one. */ continue; } strlcpy(resource, "fp/", sizeof(resource)); base16_encode(resource+3, sizeof(resource)-3, ds->digest, DIGEST_LEN); strlcat(resource, ".z", sizeof(resource)); directory_initiate_command_routerstatus( &ds->fake_status, DIR_PURPOSE_FETCH_NETWORKSTATUS, 0, /* Not private */ resource, NULL, 0 /* No payload. */); }); } else { /* A non-authority cache launches one connection to a random authority. */ /* (Check whether we're currently fetching network-status objects.) */ if (!connection_get_by_type_purpose(CONN_TYPE_DIR, DIR_PURPOSE_FETCH_NETWORKSTATUS)) directory_get_from_dirserver(DIR_PURPOSE_FETCH_NETWORKSTATUS,"all.z",1); } } /** How long (in seconds) does a client wait after getting a network status * before downloading the next in sequence? */ #define NETWORKSTATUS_CLIENT_DL_INTERVAL (30*60) /* How many times do we allow a networkstatus download to fail before we * assume that the authority isn't publishing? */ #define NETWORKSTATUS_N_ALLOWABLE_FAILURES 3 /** We are not a directory cache or authority. Update our network-status list * by launching a new directory fetch for enough network-status documents "as * necessary". See function comments for implementation details. */ static void update_networkstatus_client_downloads(time_t now) { int n_live = 0, n_dirservers, n_running_dirservers, needed = 0; int fetch_latest = 0; int most_recent_idx = -1; trusted_dir_server_t *most_recent = NULL; time_t most_recent_received = 0; char *resource, *cp; size_t resource_len; smartlist_t *missing; if (connection_get_by_type_purpose(CONN_TYPE_DIR, DIR_PURPOSE_FETCH_NETWORKSTATUS)) return; /* This is a little tricky. We want to download enough network-status * objects so that we have all of them under * NETWORKSTATUS_MAX_AGE publication time. We want to download a new * *one* if the most recent one's publication time is under * NETWORKSTATUS_CLIENT_DL_INTERVAL. */ if (!trusted_dir_servers || !smartlist_len(trusted_dir_servers)) return; n_dirservers = n_running_dirservers = smartlist_len(trusted_dir_servers); missing = smartlist_create(); SMARTLIST_FOREACH(trusted_dir_servers, trusted_dir_server_t *, ds, { networkstatus_t *ns = networkstatus_get_by_digest(ds->digest); if (ds->n_networkstatus_failures > NETWORKSTATUS_N_ALLOWABLE_FAILURES) { --n_running_dirservers; continue; } if (ns && ns->published_on > now-NETWORKSTATUS_MAX_AGE) ++n_live; else smartlist_add(missing, ds->digest); if (ns && (!most_recent || ns->received_on > most_recent_received)) { most_recent_idx = ds_sl_idx; /* magic variable from FOREACH */ most_recent = ds; most_recent_received = ns->received_on; } }); /* Also, download at least 1 every NETWORKSTATUS_CLIENT_DL_INTERVAL. */ if (!smartlist_len(missing) && most_recent_received < now-NETWORKSTATUS_CLIENT_DL_INTERVAL) { log_info(LD_DIR, "Our most recent network-status document (from %s) " "is %d seconds old; downloading another.", most_recent?most_recent->description:"nobody", (int)(now-most_recent_received)); fetch_latest = 1; needed = 1; } else if (smartlist_len(missing)) { log_info(LD_DIR, "For %d/%d running directory servers, we have %d live" " network-status documents. Downloading %d.", n_running_dirservers, n_dirservers, n_live, smartlist_len(missing)); needed = smartlist_len(missing); } else { smartlist_free(missing); return; } /* If no networkstatus was found, choose a dirserver at random as "most * recent". */ if (most_recent_idx<0) most_recent_idx = crypto_rand_int(n_dirservers); if (fetch_latest) { int i; int n_failed = 0; for (i = most_recent_idx + 1; 1; ++i) { trusted_dir_server_t *ds; if (i >= n_dirservers) i = 0; ds = smartlist_get(trusted_dir_servers, i); if (n_failed < n_dirservers && ds->n_networkstatus_failures > NETWORKSTATUS_N_ALLOWABLE_FAILURES) { ++n_failed; continue; } smartlist_add(missing, ds->digest); break; } } /* Build a request string for all the resources we want. */ resource_len = smartlist_len(missing) * (HEX_DIGEST_LEN+1) + 6; resource = tor_malloc(resource_len); memcpy(resource, "fp/", 3); cp = resource+3; needed = smartlist_len(missing); SMARTLIST_FOREACH(missing, const char *, d, { base16_encode(cp, HEX_DIGEST_LEN+1, d, DIGEST_LEN); cp += HEX_DIGEST_LEN; --needed; if (needed) *cp++ = '+'; }); memcpy(cp, ".z", 3); directory_get_from_dirserver(DIR_PURPOSE_FETCH_NETWORKSTATUS, resource, 1); tor_free(resource); smartlist_free(missing); } /** Launch requests for networkstatus documents as appropriate. */ void update_networkstatus_downloads(time_t now) { or_options_t *options = get_options(); if (server_mode(options) && options->DirPort) update_networkstatus_cache_downloads(time(NULL)); else update_networkstatus_client_downloads(time(NULL)); } /** Return 1 if all running sufficiently-stable routers will reject * addr:port, return 0 if any might accept it. */ int router_exit_policy_all_routers_reject(uint32_t addr, uint16_t port, int need_uptime) { addr_policy_result_t r; if (!routerlist) return 1; SMARTLIST_FOREACH(routerlist->routers, routerinfo_t *, router, { if (router->is_running && !router_is_unreliable(router, need_uptime, 0, 0)) { r = compare_addr_to_addr_policy(addr, port, router->exit_policy); if (r != ADDR_POLICY_REJECTED && r != ADDR_POLICY_PROBABLY_REJECTED) return 0; /* this one could be ok. good enough. */ } }); return 1; /* all will reject. */ } /** Return true iff router does not permit exit streams. */ int router_exit_policy_rejects_all(routerinfo_t *router) { return compare_addr_to_addr_policy(0, 0, router->exit_policy) == ADDR_POLICY_REJECTED; } /** Add to the list of authorized directory servers one at * address:port, with identity key digest. If * address is NULL, add ourself. */ void add_trusted_dir_server(const char *nickname, const char *address, uint16_t port, const char *digest, int supports_v1) { trusted_dir_server_t *ent; uint32_t a; char *hostname = NULL; size_t dlen; if (!trusted_dir_servers) trusted_dir_servers = smartlist_create(); if (!address) { /* The address is us; we should guess. */ if (resolve_my_address(get_options(), &a, &hostname) < 0) { log_warn(LD_CONFIG, "Couldn't find a suitable address when adding ourself as a " "trusted directory server."); return; } } else { if (tor_lookup_hostname(address, &a)) { log_warn(LD_CONFIG, "Unable to lookup address for directory server at '%s'", address); return; } hostname = tor_strdup(address); a = ntohl(a); } ent = tor_malloc_zero(sizeof(trusted_dir_server_t)); ent->nickname = nickname ? tor_strdup(nickname) : NULL; ent->address = hostname; ent->addr = a; ent->dir_port = port; ent->is_running = 1; ent->is_v1_authority = supports_v1; memcpy(ent->digest, digest, DIGEST_LEN); dlen = 64 + strlen(hostname) + (nickname?strlen(nickname):0); ent->description = tor_malloc(dlen); if (nickname) tor_snprintf(ent->description, dlen, "directory server \"%s\" at %s:%d", nickname, hostname, (int)port); else tor_snprintf(ent->description, dlen, "directory server at %s:%d", hostname, (int)port); ent->fake_status.addr = ent->addr; memcpy(ent->fake_status.identity_digest, digest, DIGEST_LEN); if (nickname) strlcpy(ent->fake_status.nickname, nickname, sizeof(ent->fake_status.nickname)); else ent->fake_status.nickname[0] = '\0'; ent->fake_status.dir_port = ent->dir_port; smartlist_add(trusted_dir_servers, ent); } /** Free storage held in ds */ void trusted_dir_server_free(trusted_dir_server_t *ds) { tor_free(ds->nickname); tor_free(ds->description); tor_free(ds->address); tor_free(ds); } /** Remove all members from the list of trusted dir servers. */ void clear_trusted_dir_servers(void) { if (trusted_dir_servers) { SMARTLIST_FOREACH(trusted_dir_servers, trusted_dir_server_t *, ent, trusted_dir_server_free(ent)); smartlist_clear(trusted_dir_servers); } else { trusted_dir_servers = smartlist_create(); } } /** Return 1 if any trusted dir server supports v1 directories, * else return 0. */ int any_trusted_dir_supports_v1(void) { if (trusted_dir_servers) SMARTLIST_FOREACH(trusted_dir_servers, trusted_dir_server_t *, ent, if (ent->is_v1_authority) return 1); return 0; } /** Return the network status with a given identity digest. */ networkstatus_t * networkstatus_get_by_digest(const char *digest) { SMARTLIST_FOREACH(networkstatus_list, networkstatus_t *, ns, { if (!memcmp(ns->identity_digest, digest, DIGEST_LEN)) return ns; }); return NULL; } /** We believe networkstatuses more recent than this when they tell us that * our server is broken, invalid, obsolete, etc. */ #define SELF_OPINION_INTERVAL (90*60) /** Return a string naming the versions of Tor recommended by * at least n_needed versioning networkstatuses */ static char * compute_recommended_versions(time_t now, int client) { int n_seen; char *current; smartlist_t *combined, *recommended; int n_recent; char *result; if (!networkstatus_list) return tor_strdup(""); combined = smartlist_create(); n_recent = 0; SMARTLIST_FOREACH(networkstatus_list, networkstatus_t *, ns, { const char *vers; smartlist_t *versions; if (! ns->recommends_versions) continue; if (ns->received_on + SELF_OPINION_INTERVAL < now) continue; n_recent++; vers = client ? ns->client_versions : ns->server_versions; if (!vers) continue; versions = smartlist_create(); smartlist_split_string(versions, vers, ",", SPLIT_SKIP_SPACE|SPLIT_IGNORE_BLANK, 0); sort_version_list(versions, 1); }); sort_version_list(combined, 0); current = NULL; n_seen = 0; recommended = smartlist_create(); SMARTLIST_FOREACH(combined, char *, cp, { if (current && !strcmp(cp, current)) { ++n_seen; } else { /* XXX Another case of requiring only half, not more than half -RD */ if (n_seen >= n_recent/2 && current) smartlist_add(recommended, current); n_seen = 0; current = cp; } }); /* XXX and here -RD */ if (n_seen >= n_recent/2 && current) smartlist_add(recommended, current); result = smartlist_join_strings(recommended, ", ", 0, NULL); SMARTLIST_FOREACH(combined, char *, cp, tor_free(cp)); smartlist_free(combined); smartlist_free(recommended); return result; } /** If the network-status list has changed since the last time we called this * function, update the status of every routerinfo from the network-status * list. */ void routers_update_all_from_networkstatus(void) { routerinfo_t *me; time_t now; if (!routerlist || !networkstatus_list || (!networkstatus_list_has_changed && !routerstatus_list_has_changed)) return; now = time(NULL); if (networkstatus_list_has_changed) routerstatus_list_update_from_networkstatus(now); routers_update_status_from_networkstatus(routerlist->routers, 0); me = router_get_my_routerinfo(); if (me && !have_warned_about_invalid_status && have_tried_downloading_all_statuses(4)) { int n_recent = 0, n_listing = 0, n_valid = 0, n_named = 0, n_naming = 0; routerstatus_t *rs; SMARTLIST_FOREACH(networkstatus_list, networkstatus_t *, ns, { if (ns->received_on + SELF_OPINION_INTERVAL < now) continue; ++n_recent; if (ns->binds_names) ++n_naming; if (!(rs = networkstatus_find_entry(ns, me->cache_info.identity_digest))) continue; ++n_listing; if (rs->is_valid) ++n_valid; if (rs->is_named) ++n_named; }); if (n_recent && n_listing) { if (n_valid <= n_recent/2) { log_warn(LD_GENERAL, "%d/%d recent statements from directory authorities list us " "as unapproved. Are you misconfigured?", n_recent-n_valid, n_recent); have_warned_about_invalid_status = 1; } else if (n_naming && !n_named) { log_warn(LD_GENERAL, "0/%d name-binding directory authorities " "recognize your nickname. Please consider sending your " "nickname and identity fingerprint to the tor-ops.", n_naming); have_warned_about_invalid_status = 1; } } } entry_guards_set_status_from_directory(); if (!have_warned_about_old_version && have_tried_downloading_all_statuses(4)) { int n_recent = 0; int n_recommended = 0; int is_server = server_mode(get_options()); version_status_t consensus = VS_RECOMMENDED; SMARTLIST_FOREACH(networkstatus_list, networkstatus_t *, ns, { version_status_t vs; if (!ns->recommends_versions || ns->received_on + SELF_OPINION_INTERVAL < now ) continue; vs = tor_version_is_obsolete( VERSION, is_server ? ns->server_versions : ns->client_versions); if (vs == VS_RECOMMENDED) ++n_recommended; if (n_recent++ == 0) { consensus = vs; } else if (consensus != vs) { consensus = version_status_join(consensus, vs); } }); if (n_recent && n_recommended <= n_recent/2) { if (consensus == VS_NEW || consensus == VS_NEW_IN_SERIES) { if (!have_warned_about_new_version) { char *rec = compute_recommended_versions(now, !is_server); log_notice(LD_GENERAL, "This version of Tor (%s) is newer than any " "recommended version%s, according to %d/%d recent network " "statuses. Versions recommended by at least %d recent " "authorit%s are: %s", VERSION, consensus == VS_NEW_IN_SERIES ? " in its series" : "", n_recent-n_recommended, n_recent, n_recent/2, n_recent/2 > 1 ? "ies" : "y", rec); have_warned_about_new_version = 1; tor_free(rec); } } else { char *rec = compute_recommended_versions(now, !is_server); log_warn(LD_GENERAL, "Please upgrade! " "This version of Tor (%s) is %s, according to " "%d/%d recent network statuses. Versions recommended by " "at least %d recent authorit%s are: %s", VERSION, consensus == VS_OLD ? "obsolete" : "not recommended", n_recent-n_recommended, n_recent, n_recent/2, n_recent/2 > 1 ? "ies" : "y", rec); have_warned_about_old_version = 1; tor_free(rec); } } else { log_info(LD_GENERAL, "%d/%d recently downloaded statements from " "directory authorities say my version is ok.", n_recommended, n_recent); } } routerstatus_list_has_changed = 0; } /** Allow any network-status newer than this to influence our view of who's * running. */ #define DEFAULT_RUNNING_INTERVAL (60*60) /** If possible, always allow at least this many network-statuses to influence * our view of who's running. */ #define MIN_TO_INFLUENCE_RUNNING 3 /** Change the is_recent field of each member of networkstatus_list so that * all members more recent than DEFAULT_RUNNING_INTERVAL are recent, and * at least the MIN_TO_INFLUENCE_RUNNING most recent members are recent, and no * others are recent. Set networkstatus_list_has_changed if anything happened. */ void networkstatus_list_update_recent(time_t now) { int n_statuses, n_recent, changed, i; char published[ISO_TIME_LEN+1]; if (!networkstatus_list) return; n_statuses = smartlist_len(networkstatus_list); n_recent = 0; changed = 0; for (i=n_statuses-1; i >= 0; --i) { networkstatus_t *ns = smartlist_get(networkstatus_list, i); trusted_dir_server_t *ds = router_get_trusteddirserver_by_digest(ns->identity_digest); const char *src = ds?ds->description:ns->source_address; if (n_recent < MIN_TO_INFLUENCE_RUNNING || ns->published_on + DEFAULT_RUNNING_INTERVAL > now) { if (!ns->is_recent) { format_iso_time(published, ns->published_on); log_info(LD_DIR, "Networkstatus from %s (published %s) is now \"recent\"", src, published); changed = 1; } ns->is_recent = 1; ++n_recent; } else { if (ns->is_recent) { format_iso_time(published, ns->published_on); log_info(LD_DIR, "Networkstatus from %s (published %s) is " "no longer \"recent\"", src, published); changed = 1; ns->is_recent = 0; } } } if (changed) networkstatus_list_has_changed = 1; } /** Helper for routerstatus_list_update_from_networkstatus: remember how many * authorities recommend a given descriptor digest. */ typedef struct { routerstatus_t *rs; int count; } desc_digest_count_t; /** Update our view of router status (as stored in routerstatus_list) from the * current set of network status documents (as stored in networkstatus_list). * Do nothing unless the network status list has changed since the last time * this function was called. */ static void routerstatus_list_update_from_networkstatus(time_t now) { or_options_t *options = get_options(); int n_trusted, n_statuses, n_recent = 0, n_naming = 0; int i, j, warned; int *index, *size; networkstatus_t **networkstatus; smartlist_t *result; strmap_t *name_map; char conflict[DIGEST_LEN]; /* Sentinel value */ desc_digest_count_t *digest_counts = NULL; /* compute which network statuses will have a vote now */ networkstatus_list_update_recent(now); if (!networkstatus_list_has_changed) return; if (!networkstatus_list) networkstatus_list = smartlist_create(); if (!routerstatus_list) routerstatus_list = smartlist_create(); if (!trusted_dir_servers) trusted_dir_servers = smartlist_create(); if (!warned_conflicts) warned_conflicts = smartlist_create(); n_trusted = smartlist_len(trusted_dir_servers); n_statuses = smartlist_len(networkstatus_list); if (n_statuses <= n_trusted/2) { /* Not enough statuses to adjust status. */ log_info(LD_DIR, "Not enough statuses to update router status list. (%d/%d)", n_statuses, n_trusted); return; } log_info(LD_DIR, "Rebuilding router status list."); index = tor_malloc(sizeof(int)*n_statuses); size = tor_malloc(sizeof(int)*n_statuses); networkstatus = tor_malloc(sizeof(networkstatus_t *)*n_statuses); for (i = 0; i < n_statuses; ++i) { index[i] = 0; networkstatus[i] = smartlist_get(networkstatus_list, i); size[i] = smartlist_len(networkstatus[i]->entries); if (networkstatus[i]->binds_names) ++n_naming; if (networkstatus[i]->is_recent) ++n_recent; } /** Iterate over all entries in all networkstatuses, and build * name_map as a map from lc nickname to identity digest. If there * is a conflict on that nickname, map the lc nickname to conflict. */ name_map = strmap_new(); memset(conflict, 0xff, sizeof(conflict)); for (i = 0; i < n_statuses; ++i) { if (!networkstatus[i]->binds_names) continue; SMARTLIST_FOREACH(networkstatus[i]->entries, routerstatus_t *, rs, { const char *other_digest; if (!rs->is_named) continue; other_digest = strmap_get_lc(name_map, rs->nickname); warned = smartlist_string_isin(warned_conflicts, rs->nickname); if (!other_digest) { strmap_set_lc(name_map, rs->nickname, rs->identity_digest); if (warned) smartlist_string_remove(warned_conflicts, rs->nickname); } else if (memcmp(other_digest, rs->identity_digest, DIGEST_LEN) && other_digest != conflict) { if (!warned) { int should_warn = options->DirPort && options->AuthoritativeDir; char fp1[HEX_DIGEST_LEN+1]; char fp2[HEX_DIGEST_LEN+1]; base16_encode(fp1, sizeof(fp1), other_digest, DIGEST_LEN); base16_encode(fp2, sizeof(fp2), rs->identity_digest, DIGEST_LEN); log_fn(should_warn ? LOG_WARN : LOG_INFO, LD_DIR, "Naming authorities disagree about which key goes with %s. " "($%s vs $%s)", rs->nickname, fp1, fp2); strmap_set_lc(name_map, rs->nickname, conflict); smartlist_add(warned_conflicts, tor_strdup(rs->nickname)); } } else { if (warned) smartlist_string_remove(warned_conflicts, rs->nickname); } }); } result = smartlist_create(); digest_counts = tor_malloc_zero(sizeof(desc_digest_count_t)*n_statuses); /* Iterate through all of the sorted routerstatus lists in lockstep. * Invariants: * - For 0 <= i < n_statuses: index[i] is an index into * networkstatus[i]->entries, which has size[i] elements. * - For i1, i2, j such that 0 <= i1 < n_statuses, 0 <= i2 < n_statues, 0 <= * j < index[i1], networkstatus[i1]->entries[j]->identity_digest < * networkstatus[i2]->entries[index[i2]]->identity_digest. * * (That is, the indices are always advanced past lower digest before * higher.) */ while (1) { int n_running=0, n_named=0, n_valid=0, n_listing=0; int n_v2_dir=0, n_fast=0, n_stable=0, n_exit=0, n_guard=0; int n_desc_digests=0, highest_count=0; const char *the_name = NULL; local_routerstatus_t *rs_out, *rs_old; routerstatus_t *rs, *most_recent; networkstatus_t *ns; const char *lowest = NULL; /* Find out which of the digests appears first. */ for (i = 0; i < n_statuses; ++i) { if (index[i] < size[i]) { rs = smartlist_get(networkstatus[i]->entries, index[i]); if (!lowest || memcmp(rs->identity_digest, lowest, DIGEST_LEN)<0) lowest = rs->identity_digest; } } if (!lowest) { /* We're out of routers. Great! */ break; } /* Okay. The routers at networkstatus[i]->entries[index[i]] whose digests * match "lowest" are next in order. Iterate over them, incrementing those * index[i] as we go. */ for (i = 0; i < n_statuses; ++i) { if (index[i] >= size[i]) continue; ns = networkstatus[i]; rs = smartlist_get(ns->entries, index[i]); if (memcmp(rs->identity_digest, lowest, DIGEST_LEN)) continue; /* At this point, we know that we're looking at a routersatus with * identity "lowest". */ ++index[i]; ++n_listing; /* Should we name this router? Only if all the names from naming * authorities match. */ if (rs->is_named && ns->binds_names) { if (!the_name) the_name = rs->nickname; if (!strcasecmp(rs->nickname, the_name)) { ++n_named; } else if (strcmp(the_name,"**mismatch**")) { char hd[HEX_DIGEST_LEN+1]; base16_encode(hd, HEX_DIGEST_LEN+1, rs->identity_digest, DIGEST_LEN); if (! smartlist_string_isin(warned_conflicts, hd)) { log_warn(LD_DIR, "Naming authorities disagree about nicknames for $%s " "(\"%s\" vs \"%s\")", hd, the_name, rs->nickname); smartlist_add(warned_conflicts, tor_strdup(hd)); } the_name = "**mismatch**"; } } /* Keep a running count of how often which descriptor digests * appear. */ for (j = 0; j < n_desc_digests; ++j) { if (!memcmp(rs->descriptor_digest, digest_counts[j].rs->descriptor_digest, DIGEST_LEN)) { if (++digest_counts[j].count > highest_count) highest_count = digest_counts[j].count; goto found; } } digest_counts[n_desc_digests].rs = rs; digest_counts[n_desc_digests].count = 1; if (!highest_count) highest_count = 1; ++n_desc_digests; found: /* Now tally up the easily-tallied flags. */ if (rs->is_valid) ++n_valid; if (rs->is_running && ns->is_recent) ++n_running; if (rs->is_exit) ++n_exit; if (rs->is_fast) ++n_fast; if (rs->is_possible_guard) ++n_guard; if (rs->is_stable) ++n_stable; if (rs->is_v2_dir) ++n_v2_dir; } /* Go over the descriptor digests and figure out which descriptor we * want. */ most_recent = NULL; for (i = 0; i < n_desc_digests; ++i) { /* If any digest appears twice or more, ignore those that don't.*/ if (highest_count >= 2 && digest_counts[i].count < 2) continue; if (!most_recent || digest_counts[i].rs->published_on > most_recent->published_on) most_recent = digest_counts[i].rs; } rs_out = tor_malloc_zero(sizeof(local_routerstatus_t)); memcpy(&rs_out->status, most_recent, sizeof(routerstatus_t)); /* Copy status info about this router, if we had any before. */ if ((rs_old = router_get_combined_status_by_digest(lowest))) { if (!memcmp(rs_out->status.descriptor_digest, most_recent->descriptor_digest, DIGEST_LEN)) { rs_out->n_download_failures = rs_old->n_download_failures; rs_out->next_attempt_at = rs_old->next_attempt_at; } rs_out->name_lookup_warned = rs_old->name_lookup_warned; } smartlist_add(result, rs_out); log_debug(LD_DIR, "Router '%s' is listed by %d/%d directories, " "named by %d/%d, validated by %d/%d, and %d/%d recent " "directories think it's running.", rs_out->status.nickname, n_listing, n_statuses, n_named, n_naming, n_valid, n_statuses, n_running, n_recent); rs_out->status.is_named = 0; if (the_name && strcmp(the_name, "**mismatch**") && n_named > 0) { const char *d = strmap_get_lc(name_map, the_name); if (d && d != conflict) rs_out->status.is_named = 1; if (smartlist_string_isin(warned_conflicts, rs_out->status.nickname)) smartlist_string_remove(warned_conflicts, rs_out->status.nickname); } if (rs_out->status.is_named) strlcpy(rs_out->status.nickname, the_name, sizeof(rs_out->status.nickname)); rs_out->status.is_valid = n_valid > n_statuses/2; rs_out->status.is_running = n_running > n_recent/2; rs_out->status.is_exit = n_exit > n_statuses/2; rs_out->status.is_fast = n_fast > n_statuses/2; rs_out->status.is_possible_guard = n_guard > n_statuses/2; rs_out->status.is_stable = n_stable > n_statuses/2; rs_out->status.is_v2_dir = n_v2_dir > n_statuses/2; } SMARTLIST_FOREACH(routerstatus_list, local_routerstatus_t *, rs, local_routerstatus_free(rs)); smartlist_free(routerstatus_list); routerstatus_list = result; tor_free(networkstatus); tor_free(index); tor_free(size); tor_free(digest_counts); strmap_free(name_map, NULL); networkstatus_list_has_changed = 0; routerstatus_list_has_changed = 1; } /** Given a list routers of routerinfo_t *, update each routers's * is_named, is_valid, and is_running fields according to our current * networkstatus_t documents. */ void routers_update_status_from_networkstatus(smartlist_t *routers, int reset_failures) { trusted_dir_server_t *ds; local_routerstatus_t *rs; or_options_t *options = get_options(); int authdir = options->AuthoritativeDir; int namingdir = options->AuthoritativeDir && options->NamingAuthoritativeDir; if (!routerstatus_list) return; SMARTLIST_FOREACH(routers, routerinfo_t *, router, { const char *digest = router->cache_info.identity_digest; rs = router_get_combined_status_by_digest(digest); ds = router_get_trusteddirserver_by_digest(digest); if (!rs) continue; if (!namingdir) router->is_named = rs->status.is_named; if (!authdir) { /* If we're not an authdir, believe others. */ router->is_valid = rs->status.is_valid; router->is_running = rs->status.is_running; router->is_fast = rs->status.is_fast; router->is_stable = rs->status.is_stable; router->is_possible_guard = rs->status.is_possible_guard; } if (router->is_running && ds) { ds->n_networkstatus_failures = 0; } if (reset_failures) { rs->n_download_failures = 0; rs->next_attempt_at = 0; } }); } /** For every router descriptor we are currently downloading by descriptor * digest, set result[d] to 1. */ static void list_pending_descriptor_downloads(digestmap_t *result) { const char *prefix = "d/"; size_t p_len = strlen(prefix); int i, n_conns; connection_t **carray; smartlist_t *tmp = smartlist_create(); tor_assert(result); get_connection_array(&carray, &n_conns); for (i = 0; i < n_conns; ++i) { connection_t *conn = carray[i]; if (conn->type == CONN_TYPE_DIR && conn->purpose == DIR_PURPOSE_FETCH_SERVERDESC && !conn->marked_for_close) { if (!strcmpstart(conn->requested_resource, prefix)) dir_split_resource_into_fingerprints(conn->requested_resource+p_len, tmp, NULL, 1); } } SMARTLIST_FOREACH(tmp, char *, d, { digestmap_set(result, d, (void*)1); tor_free(d); }); smartlist_free(tmp); } /** Launch downloads for all the descriptors whose digests are listed * as digests[i] for lo <= i < hi. (Lo and hi may be out of range.) * If source is given, download from source; otherwise, * download from an appropriate random directory server. */ static void initiate_descriptor_downloads(routerstatus_t *source, smartlist_t *digests, int lo, int hi) { int i, n = hi-lo; char *resource, *cp; size_t r_len; if (n <= 0) return; if (lo < 0) lo = 0; if (hi > smartlist_len(digests)) hi = smartlist_len(digests); r_len = 8 + (HEX_DIGEST_LEN+1)*n; cp = resource = tor_malloc(r_len); memcpy(cp, "d/", 2); cp += 2; for (i = lo; i < hi; ++i) { base16_encode(cp, r_len-(cp-resource), smartlist_get(digests,i), DIGEST_LEN); cp += HEX_DIGEST_LEN; *cp++ = '+'; } memcpy(cp-1, ".z", 3); if (source) { /* We know which authority we want. */ directory_initiate_command_routerstatus(source, DIR_PURPOSE_FETCH_SERVERDESC, 0, /* not private */ resource, NULL, 0); } else { directory_get_from_dirserver(DIR_PURPOSE_FETCH_SERVERDESC, resource, 1); } tor_free(resource); } /** Clients don't download any descriptor this recent, since it will probably * not have propageted to enough caches. */ #define ESTIMATED_PROPAGATION_TIME (10*60) /** Return 0 if this routerstatus is obsolete, too new, isn't * running, or otherwise not a descriptor that we would make any * use of even if we had it. Else return 1. */ static int client_would_use_router(routerstatus_t *rs, time_t now) { if (rs->published_on + ROUTER_MAX_AGE < now) { /* This one is too old to consider. */ return 0; } if (!rs->is_running && !get_options()->FetchUselessDescriptors) { /* If we had this router descriptor, we wouldn't even bother using it. * But, if we want to have a complete list, fetch it anyway. */ return 0; } if (rs->published_on + ESTIMATED_PROPAGATION_TIME > now) { /* Most caches probably don't have this descriptor yet. */ return 0; } return 1; } /** Return new list of ID fingerprints for routers that we (as a client) would * like to download. */ static smartlist_t * router_list_client_downloadable(void) { int n_downloadable = 0; smartlist_t *downloadable = smartlist_create(); digestmap_t *downloading; time_t now = time(NULL); /* these are just used for logging */ int n_not_ready = 0, n_in_progress = 0, n_uptodate = 0, n_wouldnt_use = 0; if (!routerstatus_list) return downloadable; downloading = digestmap_new(); list_pending_descriptor_downloads(downloading); routerstatus_list_update_from_networkstatus(now); SMARTLIST_FOREACH(routerstatus_list, local_routerstatus_t *, rs, { routerinfo_t *ri; if (!client_would_use_router(&rs->status, now)) { /* We wouldn't want this descriptor even if we got it. */ ++n_wouldnt_use; } else if (digestmap_get(downloading, rs->status.descriptor_digest)) { /* We're downloading this one now. */ ++n_in_progress; } else if (router_get_by_descriptor_digest(rs->status.descriptor_digest)) { /* We have the 'best' descriptor for this router. */ ++n_uptodate; } else if ((ri = router_get_by_digest(rs->status.identity_digest)) && ri->cache_info.published_on > rs->status.published_on) { /* Oddly, we have a descriptor more recent than the 'best' one, but it was once best. So that's okay. */ ++n_uptodate; } else if (rs->next_attempt_at > now) { /* We failed too recently to try again. */ ++n_not_ready; } else { /* Okay, time to try it. */ smartlist_add(downloadable, rs->status.descriptor_digest); ++n_downloadable; } }); #if 0 log_info(LD_DIR, "%d router descriptors are downloadable. " "%d are in progress. %d are up-to-date. " "%d are non-useful. %d failed too recently to retry.", n_downloadable, n_in_progress, n_uptodate, n_wouldnt_use, n_not_ready); #endif digestmap_free(downloading, NULL); return downloadable; } /** Initiate new router downloads as needed, using the strategy for * non-directory-servers. * * We only allow one router descriptor download at a time. * If we have less than two network-status documents, we ask * a directory for "all descriptors." * Otherwise, we ask for all descriptors that we think are different * from what we have. */ static void update_router_descriptor_client_downloads(time_t now) { /* Max amount of hashes to download per request. * Since squid does not like URLs >= 4096 bytes we limit it to 96. * 4096 - strlen(http://255.255.255.255/tor/server/d/.z) == 4058 * 4058/41 (40 for the hash and 1 for the + that separates them) => 98 * So use 96 because it's a nice number. */ #define MAX_DL_PER_REQUEST 96 /** Don't split our requests so finely that we are requesting fewer than * this number per server. */ #define MIN_DL_PER_REQUEST 4 /** To prevent a single screwy cache from confusing us by selective reply, * try to split our requests into at least this this many requests. */ #define MIN_REQUESTS 3 /** If we want fewer than this many descriptors, wait until we * want more, or until MAX_CLIENT_INTERVAL_WITHOUT_REQUEST has * passed. */ #define MAX_DL_TO_DELAY 16 /** When directory clients have only a few servers to request, they batch * them until they have more, or until this amount of time has passed. */ #define MAX_CLIENT_INTERVAL_WITHOUT_REQUEST (10*60) smartlist_t *downloadable = NULL; int should_delay, n_downloadable; or_options_t *options = get_options(); if (server_mode(options) && options->DirPort) { log_warn(LD_BUG, "Called router_descriptor_client_downloads() on a mirror?"); } /* XXX here's another magic 2 that probably should be replaced * by <= smartlist_len(trusted_dir_servers)/2 * or by a function returning same. -- weasel */ if (networkstatus_list && smartlist_len(networkstatus_list) < 2) { log_info(LD_DIR, "Not enough networkstatus documents to launch requests."); } downloadable = router_list_client_downloadable(); n_downloadable = smartlist_len(downloadable); if (n_downloadable >= MAX_DL_TO_DELAY) { log_debug(LD_DIR, "There are enough downloadable routerdescs to launch requests."); should_delay = 0; } else if (n_downloadable == 0) { // log_debug(LD_DIR, "No routerdescs need to be downloaded."); should_delay = 1; } else { should_delay = (last_routerdesc_download_attempted + MAX_CLIENT_INTERVAL_WITHOUT_REQUEST) > now; if (!should_delay) { if (last_routerdesc_download_attempted) { log_info(LD_DIR, "There are not many downloadable routerdescs, but we've " "been waiting long enough (%d seconds). Downloading.", (int)(now-last_routerdesc_download_attempted)); } else { log_info(LD_DIR, "There are not many downloadable routerdescs, but we've " "never downloaded descriptors before. Downloading."); } } } if (! should_delay) { int i, n_per_request; n_per_request = (n_downloadable+MIN_REQUESTS-1) / MIN_REQUESTS; if (n_per_request > MAX_DL_PER_REQUEST) n_per_request = MAX_DL_PER_REQUEST; if (n_per_request < MIN_DL_PER_REQUEST) n_per_request = MIN_DL_PER_REQUEST; log_info(LD_DIR, "Launching %d request%s for %d router%s, %d at a time", (n_downloadable+n_per_request-1)/n_per_request, n_downloadable>n_per_request?"s":"", n_downloadable, n_downloadable>1?"s":"", n_per_request); for (i=0; i < n_downloadable; i += n_per_request) { initiate_descriptor_downloads(NULL, downloadable, i, i+n_per_request); } last_routerdesc_download_attempted = now; } smartlist_free(downloadable); } /** Launch downloads for router status as needed, using the strategy used by * authorities and caches: download every descriptor we don't have but would * serve from a random authoritiy that lists it. */ static void update_router_descriptor_cache_downloads(time_t now) { smartlist_t **downloadable; /* For each authority, what can we dl from it? */ smartlist_t **download_from; /* ... and, what will we dl from it? */ digestmap_t *map; /* Which descs are in progress, or assigned? */ int i, j, n; int n_download; or_options_t *options = get_options(); if (!(server_mode(options) && options->DirPort)) { log_warn(LD_BUG, "Called update_router_descriptor_cache_downloads() " "on a non-mirror?"); } if (!networkstatus_list || !smartlist_len(networkstatus_list)) return; map = digestmap_new(); n = smartlist_len(networkstatus_list); downloadable = tor_malloc_zero(sizeof(smartlist_t*) * n); download_from = tor_malloc_zero(sizeof(smartlist_t*) * n); /* Set map[d]=1 for the digest of every descriptor that we are currently * downloading. */ list_pending_descriptor_downloads(map); /* For the digest of every descriptor that we don't have, and that we aren't * downloading, add d to downloadable[i] if the i'th networkstatus knows * about that descriptor, and we haven't already failed to get that * descriptor from the corresponding authority. */ n_download = 0; SMARTLIST_FOREACH(networkstatus_list, networkstatus_t *, ns, { smartlist_t *dl = smartlist_create(); downloadable[ns_sl_idx] = dl; download_from[ns_sl_idx] = smartlist_create(); SMARTLIST_FOREACH(ns->entries, routerstatus_t * , rs, { if (!rs->need_to_mirror) continue; if (router_get_by_descriptor_digest(rs->descriptor_digest)) { log_warn(LD_BUG, "Bug: We have a router descriptor, but need_to_mirror=1."); rs->need_to_mirror = 0; continue; } if (options->AuthoritativeDir && dirserv_would_reject_router(rs)) { rs->need_to_mirror = 0; continue; } if (digestmap_get(map, rs->descriptor_digest)) { /* We're downloading it already. */ continue; } else { /* We could download it from this guy. */ smartlist_add(dl, rs->descriptor_digest); ++n_download; } }); }); /* At random, assign descriptors to authorities such that: * - if d is a member of some downloadable[x], d is a member of some * download_from[y]. (Everything we want to download, we try to download * from somebody.) * - If d is a member of download_from[y], d is a member of downloadable[y]. * (We only try to download descriptors from authorities who claim to have * them.) * - No d is a member of download_from[x] and download_from[y] s.t. x != y. * (We don't try to download anything from two authorities concurrently.) */ while (n_download) { int which_ns = crypto_rand_int(n); smartlist_t *dl = downloadable[which_ns]; int idx; char *d; tor_assert(dl); if (!smartlist_len(dl)) continue; idx = crypto_rand_int(smartlist_len(dl)); d = smartlist_get(dl, idx); if (! digestmap_get(map, d)) { smartlist_add(download_from[which_ns], d); digestmap_set(map, d, (void*) 1); } smartlist_del(dl, idx); --n_download; } /* Now, we can actually launch our requests. */ for (i=0; iidentity_digest); smartlist_t *dl = download_from[i]; if (!ds) { log_warn(LD_BUG, "Networkstatus with no corresponding authority!"); continue; } if (! smartlist_len(dl)) continue; log_info(LD_DIR, "Requesting %d descriptors from authority \"%s\"", smartlist_len(dl), ds->nickname); for (j=0; j < smartlist_len(dl); j += MAX_DL_PER_REQUEST) { initiate_descriptor_downloads(&(ds->fake_status), dl, j, j+MAX_DL_PER_REQUEST); } } for (i=0; iDirPort) { update_router_descriptor_cache_downloads(now); } else { update_router_descriptor_client_downloads(now); } } static int routerstatus_count_usable_entries(smartlist_t *entries) { int count = 0; time_t now = time(NULL); SMARTLIST_FOREACH(entries, routerstatus_t *, rs, if (client_would_use_router(rs, now)) count++); return count; } /** Return true iff we have enough networkstatus and router information to * start building circuits. Right now, this means "more than half the * networkstatus documents, and at least 1/4 of expected routers." */ //XXX should consider whether we have enough exiting nodes here. int router_have_minimum_dir_info(void) { int tot = 0, num_running = 0; int n_ns, n_authorities, res, avg; static int have_enough = 0; if (!networkstatus_list || !routerlist) { res = 0; goto done; } n_authorities = smartlist_len(trusted_dir_servers); n_ns = smartlist_len(networkstatus_list); if (n_ns<=n_authorities/2) { log_info(LD_DIR, "We have %d of %d network statuses, and we want " "more than %d.", n_ns, n_authorities, n_authorities/2); res = 0; goto done; } SMARTLIST_FOREACH(networkstatus_list, networkstatus_t *, ns, tot += routerstatus_count_usable_entries(ns->entries)); avg = tot / n_ns; SMARTLIST_FOREACH(routerstatus_list, local_routerstatus_t *, rs, { if (rs->status.is_running) num_running++; }); res = smartlist_len(routerlist->routers) >= (avg/4) && num_running > 2; done: if (res && !have_enough) { log(LOG_NOTICE, LD_DIR, "We now have enough directory information to build circuits."); } if (!res && have_enough) { log(LOG_NOTICE, LD_DIR,"Our directory information is no longer up-to-date " "enough to build circuits.%s", num_running > 2 ? "" : " (Not enough servers seem reachable -- " "is your network connection down?)"); } have_enough = res; return res; } /** Return true iff we have downloaded, or attempted to download at least * n_failures times, a network status for each authority. */ static int have_tried_downloading_all_statuses(int n_failures) { if (!trusted_dir_servers) return 0; SMARTLIST_FOREACH(trusted_dir_servers, trusted_dir_server_t *, ds, { /* If we don't have the status, and we haven't failed to get the status, * we haven't tried to get the status. */ if (!networkstatus_get_by_digest(ds->digest) && ds->n_networkstatus_failures <= n_failures) return 0; }); return 1; } /** Reset the descriptor download failure count on all routers, so that we * can retry any long-failed routers immediately. */ void router_reset_descriptor_download_failures(void) { if (!routerstatus_list) return; SMARTLIST_FOREACH(routerstatus_list, local_routerstatus_t *, rs, { rs->n_download_failures = 0; rs->next_attempt_at = 0; }); tor_assert(networkstatus_list); SMARTLIST_FOREACH(networkstatus_list, networkstatus_t *, ns, SMARTLIST_FOREACH(ns->entries, routerstatus_t *, rs, { if (!router_get_by_descriptor_digest(rs->descriptor_digest)) rs->need_to_mirror = 1; })); last_routerdesc_download_attempted = 0; } /** Any changes in a router descriptor's publication time larger than this are * automatically non-cosmetic. */ #define ROUTER_MAX_COSMETIC_TIME_DIFFERENCE (12*60*60) /** Return true iff the only differences between r1 and r2 are such that * would not cause a recent (post 0.1.1.6) dirserver to republish. */ int router_differences_are_cosmetic(routerinfo_t *r1, routerinfo_t *r2) { time_t r1pub, r2pub; tor_assert(r1 && r2); /* r1 should be the one that was published first. */ if (r1->cache_info.published_on > r2->cache_info.published_on) { routerinfo_t *ri_tmp = r2; r2 = r1; r1 = ri_tmp; } /* If any key fields differ, they're different. */ if (strcasecmp(r1->address, r2->address) || strcasecmp(r1->nickname, r2->nickname) || r1->or_port != r2->or_port || r1->dir_port != r2->dir_port || crypto_pk_cmp_keys(r1->onion_pkey, r2->onion_pkey) || crypto_pk_cmp_keys(r1->identity_pkey, r2->identity_pkey) || strcasecmp(r1->platform, r2->platform) || (r1->contact_info && !r2->contact_info) || /* contact_info is optional */ (!r1->contact_info && r2->contact_info) || (r1->contact_info && r2->contact_info && strcasecmp(r1->contact_info, r2->contact_info)) || r1->is_hibernating != r2->is_hibernating || cmp_addr_policies(r1->exit_policy, r2->exit_policy)) return 0; if ((r1->declared_family == NULL) != (r2->declared_family == NULL)) return 0; if (r1->declared_family && r2->declared_family) { int i, n; if (smartlist_len(r1->declared_family)!=smartlist_len(r2->declared_family)) return 0; n = smartlist_len(r1->declared_family); for (i=0; i < n; ++i) { if (strcasecmp(smartlist_get(r1->declared_family, i), smartlist_get(r2->declared_family, i))) return 0; } } /* Did bandwidth change a lot? */ if ((r1->bandwidthcapacity < r2->bandwidthcapacity/2) || (r2->bandwidthcapacity < r1->bandwidthcapacity/2)) return 0; /* Did more than 12 hours pass? */ if (r1->cache_info.published_on + ROUTER_MAX_COSMETIC_TIME_DIFFERENCE < r2->cache_info.published_on) return 0; /* Did uptime fail to increase by approximately the amount we would think, * give or take 30 minutes? */ r1pub = r1->cache_info.published_on; r2pub = r2->cache_info.published_on; if (abs(r2->uptime - (r1->uptime + (r2pub - r1pub)))) return 0; /* Otherwise, the difference is cosmetic. */ return 1; } static void routerlist_assert_ok(routerlist_t *rl) { digestmap_iter_t *iter; routerinfo_t *r2; signed_descriptor_t *sd2; if (!routerlist) return; SMARTLIST_FOREACH(rl->routers, routerinfo_t *, r, { r2 = digestmap_get(rl->identity_map, r->cache_info.identity_digest); tor_assert(r == r2); sd2 = digestmap_get(rl->desc_digest_map, r->cache_info.signed_descriptor_digest); tor_assert(&(r->cache_info) == sd2); }); SMARTLIST_FOREACH(rl->old_routers, signed_descriptor_t *, sd, { r2 = digestmap_get(rl->identity_map, sd->identity_digest); tor_assert(sd != &(r2->cache_info)); sd2 = digestmap_get(rl->desc_digest_map, sd->signed_descriptor_digest); tor_assert(sd == sd2); }); iter = digestmap_iter_init(rl->identity_map); while (!digestmap_iter_done(iter)) { const char *d; void *_r; routerinfo_t *r; digestmap_iter_get(iter, &d, &_r); r = _r; tor_assert(!memcmp(r->cache_info.identity_digest, d, DIGEST_LEN)); iter = digestmap_iter_next(rl->identity_map, iter); } iter = digestmap_iter_init(rl->desc_digest_map); while (!digestmap_iter_done(iter)) { const char *d; void *_sd; signed_descriptor_t *sd; digestmap_iter_get(iter, &d, &_sd); sd = _sd; tor_assert(!memcmp(sd->signed_descriptor_digest, d, DIGEST_LEN)); iter = digestmap_iter_next(rl->desc_digest_map, iter); } } /** Allocate and return a new string representing the contact info * and platform string for router, * surrounded by quotes and using standard C escapes. * * THIS FUNCTION IS NOT REENTRANT. Don't call it from outside the main * thread. Also, each call invalidates the last-returned value, so don't * try log_warn(LD_GENERAL, "%s %s", esc_router_info(a), esc_router_info(b)); */ const char * esc_router_info(routerinfo_t *router) { static char *info; char *esc_contact, *esc_platform; size_t len; if (info) tor_free(info); esc_contact = esc_for_log(router->contact_info); esc_platform = esc_for_log(router->platform); len = strlen(esc_contact)+strlen(esc_platform)+32; info = tor_malloc(len); tor_snprintf(info, len, "Contact %s, Platform %s", esc_contact, esc_platform); tor_free(esc_contact); tor_free(esc_platform); return info; }