/* Copyright 2001,2002,2003 Roger Dingledine, Matej Pfajfar. */ /* See LICENSE for licensing information */ /* $Id$ */ #include "or.h" /** * \file router.c * \brief OR functionality, including key maintenance, generating * and uploading server descriptors, retrying OR connections. **/ extern or_options_t options; /* command-line and config-file options */ extern long stats_n_seconds_uptime; /** Exposed for test.c. */ void get_platform_str(char *platform, int len); /************************************************************/ /***** * Key management: ORs only. *****/ /** Private keys for this OR. There is also an SSL key managed by tortls.c. */ static tor_mutex_t *key_lock=NULL; static time_t onionkey_set_at=0; /* When was onionkey last changed? */ static crypto_pk_env_t *onionkey=NULL; static crypto_pk_env_t *lastonionkey=NULL; static crypto_pk_env_t *identitykey=NULL; /** Replace the current onion key with k. Does not affect lastonionkey; * to update onionkey correctly, call rotate_onion_key(). */ void set_onion_key(crypto_pk_env_t *k) { tor_mutex_acquire(key_lock); onionkey = k; onionkey_set_at = time(NULL); tor_mutex_release(key_lock); } /** Return the current onion key. Requires that the onion key has been * loaded or generated. */ crypto_pk_env_t *get_onion_key(void) { tor_assert(onionkey); return onionkey; } /** Return the onion key that was current before the most recent onion * key rotation. If no rotation has been performed since this process * started, return NULL. */ crypto_pk_env_t *get_previous_onion_key(void) { return lastonionkey; } void dup_onion_keys(crypto_pk_env_t **key, crypto_pk_env_t **last) { tor_assert(key && last); tor_mutex_acquire(key_lock); *key = crypto_pk_dup_key(onionkey); if (lastonionkey) *last = crypto_pk_dup_key(lastonionkey); else *last = NULL; tor_mutex_release(key_lock); } /** Return the time when the onion key was last set. This is either the time * when the process launched, or the time of the most recent key rotation since * the process launched. */ time_t get_onion_key_set_at(void) { return onionkey_set_at; } /** Set the current identity key to k. */ void set_identity_key(crypto_pk_env_t *k) { identitykey = k; } /** Returns the current identity key; requires that the identity key has been * set. */ crypto_pk_env_t *get_identity_key(void) { tor_assert(identitykey); return identitykey; } /** Replace the previous onion key with the current onion key, and generate * a new previous onion key. Immediately after calling this function, * the OR should: * - schedule all previous cpuworkers to shut down _after_ processing * pending work. (This will cause fresh cpuworkers to be generated.) * - generate and upload a fresh routerinfo. */ void rotate_onion_key(void) { char fname[512]; crypto_pk_env_t *prkey; sprintf(fname,"%s/keys/onion.key",get_data_directory(&options)); if (!(prkey = crypto_new_pk_env())) { log(LOG_ERR, "Error creating crypto environment."); goto error; } if (crypto_pk_generate_key(prkey)) { log(LOG_ERR, "Error generating onion key"); goto error; } if (crypto_pk_write_private_key_to_filename(prkey, fname)) { log(LOG_ERR, "Couldn't write generated key to %s.", fname); goto error; } tor_mutex_acquire(key_lock); if (lastonionkey) crypto_free_pk_env(lastonionkey); log_fn(LOG_INFO, "Rotating onion key"); lastonionkey = onionkey; set_onion_key(prkey); tor_mutex_release(key_lock); return; error: log_fn(LOG_WARN, "Couldn't rotate onion key."); } /* Read an RSA secret key key from a file that was once named fname_old, * but is now named fname_new. Rename the file from old to new as needed. */ crypto_pk_env_t *init_key_from_file_name_changed(const char *fname_old, const char *fname_new) { int fs; fs = file_status(fname_new); if (fs == FN_FILE) /* The new filename is there. */ return init_key_from_file(fname_new); fs = file_status(fname_old); if (fs != FN_FILE) /* There is no key under either name. */ return init_key_from_file(fname_new); /* The old filename exists, and the new one doesn't. Rename and load. */ if (rename(fname_old, fname_new) < 0) { log_fn(LOG_ERR, "Couldn't rename %s to %s: %s", fname_old, fname_new, strerror(errno)); return NULL; } return init_key_from_file(fname_new); } /** Try to read an RSA key from fname. If fname doesn't exist, * create a new RSA key and save it in fname. Return the read/created * key, or NULL on error. */ crypto_pk_env_t *init_key_from_file(const char *fname) { crypto_pk_env_t *prkey = NULL; FILE *file = NULL; if (!(prkey = crypto_new_pk_env())) { log(LOG_ERR, "Error creating crypto environment."); goto error; } switch(file_status(fname)) { case FN_DIR: case FN_ERROR: log(LOG_ERR, "Can't read key from %s", fname); goto error; case FN_NOENT: log(LOG_INFO, "No key found in %s; generating fresh key.", fname); if (crypto_pk_generate_key(prkey)) { log(LOG_ERR, "Error generating onion key"); goto error; } if (crypto_pk_check_key(prkey) <= 0) { log(LOG_ERR, "Generated key seems invalid"); goto error; } log(LOG_INFO, "Generated key seems valid"); if (crypto_pk_write_private_key_to_filename(prkey, fname)) { log(LOG_ERR, "Couldn't write generated key to %s.", fname); goto error; } return prkey; case FN_FILE: if (crypto_pk_read_private_key_from_filename(prkey, fname)) { log(LOG_ERR, "Error loading private key."); goto error; } return prkey; default: tor_assert(0); } error: if (prkey) crypto_free_pk_env(prkey); if (file) fclose(file); return NULL; } /** Initialize all OR private keys, and the TLS context, as necessary. * On OPs, this only initializes the tls context. */ int init_keys(void) { char keydir[512]; char keydir2[512]; char fingerprint[FINGERPRINT_LEN+MAX_NICKNAME_LEN+3]; char *cp; const char *tmp, *mydesc, *datadir; crypto_pk_env_t *prkey; if (!key_lock) key_lock = tor_mutex_new(); /* OP's don't need persistant keys; just make up an identity and * initialize the TLS context. */ if (!server_mode()) { tor_assert(!options.DirPort); #if 0 /* XXXX008 enable this once we make ORs tolerate unknown routers. */ if (!(prkey = crypto_new_pk_env())) return -1; if (crypto_pk_generate_key(prkey)) return -1; set_identity_key(prkey); if (tor_tls_context_new(get_identity_key(), 1, options.Nickname, MAX_SSL_KEY_LIFETIME) < 0) { log_fn(LOG_ERR, "Error creating TLS context for OP."); return -1; } #endif if (tor_tls_context_new(NULL, 0, NULL, MAX_SSL_KEY_LIFETIME)<0) { log_fn(LOG_ERR, "Error creating TLS context for OP."); return -1; } return 0; } /* Make sure DataDirectory exists, and is private. */ datadir = get_data_directory(&options); tor_assert(datadir); if (strlen(datadir) > (512-128)) { log_fn(LOG_ERR, "DataDirectory is too long."); return -1; } if (check_private_dir(datadir, 1)) { return -1; } /* Check the key directory. */ sprintf(keydir,"%s/keys", datadir); if (check_private_dir(keydir, 1)) { return -1; } cp = keydir + strlen(keydir); /* End of string. */ /* 1. Read identity key. Make it if none is found. */ sprintf(keydir,"%s/keys/identity.key",datadir); sprintf(keydir2,"%s/keys/secret_id_key",datadir); log_fn(LOG_INFO,"Reading/making identity key %s...",keydir2); prkey = init_key_from_file_name_changed(keydir,keydir2); if (!prkey) return -1; set_identity_key(prkey); /* 2. Read onion key. Make it if none is found. */ sprintf(keydir,"%s/keys/onion.key",datadir); sprintf(keydir2,"%s/keys/secret_onion_key",datadir); log_fn(LOG_INFO,"Reading/making onion key %s...",keydir2); prkey = init_key_from_file_name_changed(keydir,keydir2); if (!prkey) return -1; set_onion_key(prkey); /* 3. Initialize link key and TLS context. */ if (tor_tls_context_new(get_identity_key(), 1, options.Nickname, MAX_SSL_KEY_LIFETIME) < 0) { log_fn(LOG_ERR, "Error initializing TLS context"); return -1; } /* 4. Dump router descriptor to 'router.desc' */ /* Must be called after keys are initialized. */ if (!(router_get_my_descriptor())) { log_fn(LOG_ERR, "Error initializing descriptor."); return -1; } /* We need to add our own fingerprint so it gets recognized. */ if (dirserv_add_own_fingerprint(options.Nickname, get_identity_key())) { log_fn(LOG_ERR, "Error adding own fingerprint to approved set"); return -1; } tmp = mydesc = router_get_my_descriptor(); if (dirserv_add_descriptor(&tmp) != 1) { log(LOG_ERR, "Unable to add own descriptor to directory."); return -1; } sprintf(keydir,"%s/router.desc", datadir); log_fn(LOG_INFO,"Dumping descriptor to %s...",keydir); if (write_str_to_file(keydir, mydesc)) { return -1; } /* 5. Dump fingerprint to 'fingerprint' */ sprintf(keydir,"%s/fingerprint", datadir); log_fn(LOG_INFO,"Dumping fingerprint to %s...",keydir); tor_assert(strlen(options.Nickname) <= MAX_NICKNAME_LEN); strcpy(fingerprint, options.Nickname); strcat(fingerprint, " "); if (crypto_pk_get_fingerprint(get_identity_key(), fingerprint+strlen(fingerprint))<0) { log_fn(LOG_ERR, "Error computing fingerprint"); return -1; } strcat(fingerprint, "\n"); if (write_str_to_file(keydir, fingerprint)) return -1; if(!options.DirPort) return 0; /* 6. [dirserver only] load approved-routers file */ sprintf(keydir,"%s/approved-routers", datadir); log_fn(LOG_INFO,"Loading approved fingerprints from %s...",keydir); if(dirserv_parse_fingerprint_file(keydir) < 0) { log_fn(LOG_ERR, "Error loading fingerprints"); return -1; } /* 7. [dirserver only] load old directory, if it's there */ sprintf(keydir,"%s/cached-directory", datadir); log_fn(LOG_INFO,"Loading cached directory from %s...",keydir); cp = read_file_to_str(keydir); if(!cp) { log_fn(LOG_INFO,"Cached directory %s not present. Ok.",keydir); } else { if(options.AuthoritativeDir) { if(dirserv_load_from_directory_string(cp) < 0){ log_fn(LOG_ERR, "Cached directory %s is corrupt", keydir); tor_free(cp); return -1; } } else { /* set time to 1 so it will be replaced on first download. */ dirserv_set_cached_directory(cp, 1); } tor_free(cp); } /* success */ return 0; } /* * Clique maintenance */ /** OR only: try to open connections to all of the other ORs we know about. */ void router_retry_connections(void) { int i; routerinfo_t *router; routerlist_t *rl; router_get_routerlist(&rl); for (i=0;i < smartlist_len(rl->routers);i++) { router = smartlist_get(rl->routers, i); if(router_is_me(router)) continue; if(!connection_get_by_identity_digest(router->identity_digest, CONN_TYPE_OR)) { /* not in the list */ log_fn(LOG_DEBUG,"connecting to OR %s:%u.",router->address,router->or_port); connection_or_connect(router->addr, router->or_port, router->identity_digest); } } } /* * OR descriptor generation. */ /** My routerinfo. */ static routerinfo_t *desc_routerinfo = NULL; /** String representation of my descriptor, signed by me. */ static char descriptor[8192]; /** OR only: try to upload our signed descriptor to all the directory servers * we know about. */ void router_upload_dir_desc_to_dirservers(void) { const char *s; s = router_get_my_descriptor(); if (!s) { log_fn(LOG_WARN, "No descriptor; skipping upload"); return; } directory_post_to_dirservers(DIR_PURPOSE_UPLOAD_DIR, s, strlen(s)); } #define DEFAULT_EXIT_POLICY "reject 0.0.0.0/8,reject 169.254.0.0/16,reject 127.0.0.0/8,reject 192.168.0.0/16,reject 10.0.0.0/8,reject 172.16.0.0/12,accept *:20-22,accept *:53,accept *:79-81,accept *:110,accept *:143,accept *:443,accept *:873,accept *:993,accept *:995,accept *:1024-65535,reject *:*" /** Set the exit policy on router to match the exit policy in the * current configuration file. If the exit policy doesn't have a catch-all * rule, then append the default exit policy as well. */ static void router_add_exit_policy_from_config(routerinfo_t *router) { struct exit_policy_t *ep; struct config_line_t default_policy; config_parse_exit_policy(options.ExitPolicy, &router->exit_policy); for (ep = router->exit_policy; ep; ep = ep->next) { if (ep->msk == 0 && ep->prt_min <= 1 && ep->prt_max >= 65535) { /* if exitpolicy includes a *:* line, then we're done. */ return; } } /* Else, append the default exitpolicy. */ default_policy.key = NULL; default_policy.value = DEFAULT_EXIT_POLICY; default_policy.next = NULL; config_parse_exit_policy(&default_policy, &router->exit_policy); } /** OR only: Return false if my exit policy says to allow connection to * conn. Else return true. */ int router_compare_to_my_exit_policy(connection_t *conn) { tor_assert(desc_routerinfo); /* make sure it's resolved to something. this way we can't get a 'maybe' below. */ if (!conn->addr) return -1; return router_compare_addr_to_exit_policy(conn->addr, conn->port, desc_routerinfo->exit_policy); } /** Return true iff router has the same nickname as this OR. (For an * OP, always returns false.) */ int router_is_me(routerinfo_t *router) { tor_assert(router); /* XXXX008 should compare identity instead? */ return options.Nickname && !strcasecmp(router->nickname, options.Nickname); } /** Return a routerinfo for this OR, rebuilding a fresh one if * necessary. Return NULL on error, or if called on an OP. */ routerinfo_t *router_get_my_routerinfo(void) { if (!server_mode()) return NULL; if (!desc_routerinfo) { if (router_rebuild_descriptor()) return NULL; } return desc_routerinfo; } /** OR only: Return a signed server descriptor for this OR, rebuilding a fresh * one if necessary. Return NULL on error. */ const char *router_get_my_descriptor(void) { if (!desc_routerinfo) { if (router_rebuild_descriptor()) return NULL; } log_fn(LOG_DEBUG,"my desc is '%s'",descriptor); return descriptor; } /** Rebuild a fresh routerinfo and signed server descriptor for this * OR. Return 0 on success, -1 on error. */ int router_rebuild_descriptor(void) { routerinfo_t *ri; struct in_addr addr; char platform[256]; if (!tor_inet_aton(options.Address, &addr)) { log_fn(LOG_ERR, "options.Address didn't hold an IP."); return -1; } ri = tor_malloc_zero(sizeof(routerinfo_t)); ri->address = tor_strdup(options.Address); ri->nickname = tor_strdup(options.Nickname); ri->addr = (uint32_t) ntohl(addr.s_addr); ri->or_port = options.ORPort; ri->socks_port = options.SocksPort; ri->dir_port = options.DirPort; ri->published_on = time(NULL); ri->onion_pkey = crypto_pk_dup_key(get_onion_key()); /* must invoke from main thread */ ri->identity_pkey = crypto_pk_dup_key(get_identity_key()); if (crypto_pk_get_digest(ri->identity_pkey, ri->identity_digest)<0) { routerinfo_free(ri); return -1; } get_platform_str(platform, sizeof(platform)); ri->platform = tor_strdup(platform); ri->bandwidthrate = options.BandwidthRate; ri->bandwidthburst = options.BandwidthBurst; ri->exit_policy = NULL; /* zero it out first */ router_add_exit_policy_from_config(ri); if (desc_routerinfo) routerinfo_free(desc_routerinfo); desc_routerinfo = ri; if (router_dump_router_to_string(descriptor, 8192, ri, get_identity_key())<0) { log_fn(LOG_WARN, "Couldn't dump router to string."); return -1; } if (ri->dir_port) ri->is_trusted_dir = 1; return 0; } /** Set platform (max length len) to a NUL-terminated short * string describing the version of Tor and the operating system we're * currently running on. */ void get_platform_str(char *platform, int len) { snprintf(platform, len-1, "Tor %s (up %ld sec) on %s", VERSION, stats_n_seconds_uptime, get_uname()); platform[len-1] = '\0'; return; } /* XXX need to audit this thing and count fenceposts. maybe * refactor so we don't have to keep asking if we're * near the end of maxlen? */ #define DEBUG_ROUTER_DUMP_ROUTER_TO_STRING /** OR only: Given a routerinfo for this router, and an identity key to sign * with, encode the routerinfo as a signed server descriptor and write the * result into s, using at most maxlen bytes. Return -1 on * failure, and the number of bytes used on success. */ int router_dump_router_to_string(char *s, int maxlen, routerinfo_t *router, crypto_pk_env_t *ident_key) { char *onion_pkey; /* Onion key, PEM-encoded. */ char *identity_pkey; /* Identity key, PEM-encoded. */ char digest[20]; char signature[128]; char published[32]; struct in_addr in; int onion_pkeylen, identity_pkeylen; int written; int result=0; struct exit_policy_t *tmpe; #ifdef DEBUG_ROUTER_DUMP_ROUTER_TO_STRING char *s_tmp, *s_dup; const char *cp; routerinfo_t *ri_tmp; #endif /* Make sure the identity key matches the one in the routerinfo. */ if (crypto_pk_cmp_keys(ident_key, router->identity_pkey)) { log_fn(LOG_WARN,"Tried to sign a router with a private key that didn't match router's public key!"); return -1; } /* PEM-encode the onion key */ if(crypto_pk_write_public_key_to_string(router->onion_pkey, &onion_pkey,&onion_pkeylen)<0) { log_fn(LOG_WARN,"write onion_pkey to string failed!"); return -1; } /* PEM-encode the identity key key */ if(crypto_pk_write_public_key_to_string(router->identity_pkey, &identity_pkey,&identity_pkeylen)<0) { log_fn(LOG_WARN,"write identity_pkey to string failed!"); tor_free(onion_pkey); return -1; } /* Encode the publication time. */ strftime(published, 32, "%Y-%m-%d %H:%M:%S", gmtime(&router->published_on)); /* Generate the easy portion of the router descriptor. */ result = snprintf(s, maxlen, "router %s %s %d %d %d\n" "platform %s\n" "published %s\n" "bandwidth %d %d %d\n" "onion-key\n%s" "signing-key\n%s", router->nickname, router->address, router->or_port, router->socks_port, /* Due to an 0.0.7 bug, we can't actually say that we have a dirport unles * we're an authoritative directory. */ router->is_trusted_dir ? router->dir_port : 0, router->platform, published, (int) router->bandwidthrate, (int) router->bandwidthburst, (int) router->advertisedbandwidth, onion_pkey, identity_pkey); tor_free(onion_pkey); tor_free(identity_pkey); if(result < 0 || result >= maxlen) { /* apparently different glibcs do different things on snprintf error.. so check both */ return -1; } /* From now on, we use 'written' to remember the current length of 's'. */ written = result; if (router->dir_port && !router->is_trusted_dir) { /* dircacheport wasn't recognized before 0.0.8pre. (When 0.0.7 is gone, * we can fold this back into dirport anyway.) */ result = snprintf(s+written,maxlen-written, "opt dircacheport %d\n", router->dir_port); if (result<0 || result+written > maxlen) return -1; written += result; } if (options.ContactInfo && strlen(options.ContactInfo)) { result = snprintf(s+written,maxlen-written, "opt contact %s\n", options.ContactInfo); if (result<0 || result+written > maxlen) return -1; written += result; } /* Write the exit policy to the end of 's'. */ for(tmpe=router->exit_policy; tmpe; tmpe=tmpe->next) { in.s_addr = htonl(tmpe->addr); /* Write: "accept 1.2.3.4" */ result = snprintf(s+written, maxlen-written, "%s %s", tmpe->policy_type == EXIT_POLICY_ACCEPT ? "accept" : "reject", tmpe->msk == 0 ? "*" : inet_ntoa(in)); if(result < 0 || result+written > maxlen) { /* apparently different glibcs do different things on snprintf error.. so check both */ return -1; } written += result; if (tmpe->msk != 0xFFFFFFFFu && tmpe->msk != 0) { /* Write "/255.255.0.0" */ in.s_addr = htonl(tmpe->msk); result = snprintf(s+written, maxlen-written, "/%s", inet_ntoa(in)); if (result<0 || result+written > maxlen) return -1; written += result; } if (tmpe->prt_min == 0 && tmpe->prt_max == 65535) { /* There is no port set; write ":*" */ if (written > maxlen-4) return -1; strcat(s+written, ":*\n"); written += 3; } else if (tmpe->prt_min == tmpe->prt_max) { /* There is only one port; write ":80". */ result = snprintf(s+written, maxlen-written, ":%d\n", tmpe->prt_min); if (result<0 || result+written > maxlen) return -1; written += result; } else { /* There is a range of ports; write ":79-80". */ result = snprintf(s+written, maxlen-written, ":%d-%d\n", tmpe->prt_min, tmpe->prt_max); if (result<0 || result+written > maxlen) return -1; written += result; } } /* end for */ if (written > maxlen-256) /* Not enough room for signature. */ return -1; /* Sign the directory */ strcat(s+written, "router-signature\n"); written += strlen(s+written); s[written] = '\0'; if (router_get_router_hash(s, digest) < 0) return -1; if (crypto_pk_private_sign(ident_key, digest, 20, signature) < 0) { log_fn(LOG_WARN, "Error signing digest"); return -1; } strcat(s+written, "-----BEGIN SIGNATURE-----\n"); written += strlen(s+written); if (base64_encode(s+written, maxlen-written, signature, 128) < 0) { log_fn(LOG_WARN, "Couldn't base64-encode signature"); return -1; } written += strlen(s+written); strcat(s+written, "-----END SIGNATURE-----\n"); written += strlen(s+written); if (written > maxlen-2) return -1; /* include a last '\n' */ s[written] = '\n'; s[written+1] = 0; #ifdef DEBUG_ROUTER_DUMP_ROUTER_TO_STRING cp = s_tmp = s_dup = tor_strdup(s); ri_tmp = router_parse_entry_from_string(cp, NULL); if (!ri_tmp) { log_fn(LOG_ERR, "We just generated a router descriptor we can't parse: <<%s>>", s); return -1; } free(s_dup); routerinfo_free(ri_tmp); #endif return written+1; } /* Local Variables: mode:c indent-tabs-mode:nil c-basic-offset:2 End: */