/* Copyright 2001 Matej Pfajfar. * Copyright 2001-2004 Roger Dingledine. * Copyright 2004-2005 Roger Dingledine, Nick Mathewson. */ /* See LICENSE for licensing information */ /* $Id$ */ const char routerparse_c_id[] = "$Id$"; /** * \file routerparse.c * \brief Code to parse and validate router descriptors and directories. **/ #include "or.h" /****************************************************************************/ /** Enumeration of possible token types. The ones starting with K_ * correspond to directory 'keywords'. _UNRECOGNIZED is for an * unrecognized keyword; _ERR is an error in the tokenizing process, * _EOF is an end-of-file marker, and _NIL is used to encode * not-a-token. */ typedef enum { K_ACCEPT, K_DIRECTORY_SIGNATURE, K_RECOMMENDED_SOFTWARE, K_REJECT, K_ROUTER, K_SIGNED_DIRECTORY, K_SIGNING_KEY, K_ONION_KEY, K_ROUTER_SIGNATURE, K_PUBLISHED, K_RUNNING_ROUTERS, K_ROUTER_STATUS, K_PLATFORM, K_OPT, K_BANDWIDTH, K_PORTS, K_CONTACT, K_NETWORK_STATUS, K_UPTIME, K_DIR_SIGNING_KEY, K_FAMILY, K_FINGERPRINT, K_HIBERNATING, K_READ_HISTORY, K_WRITE_HISTORY, _UNRECOGNIZED, _ERR, _EOF, _NIL } directory_keyword; /** Structure to hold a single directory token. * * We parse a directory by breaking it into "tokens", each consisting * of a keyword, a line full of arguments, and a binary object. The * arguments and object are both optional, depending on the keyword * type. */ typedef struct directory_token_t { directory_keyword tp; /**< Type of the token. */ int n_args; /**< Number of elements in args */ char **args; /**< Array of arguments from keyword line. */ char *object_type; /**< -----BEGIN [object_type]-----*/ size_t object_size; /**< Bytes in object_body */ char *object_body; /**< Contents of object, base64-decoded. */ crypto_pk_env_t *key; /**< For public keys only. */ const char *error; /**< For _ERR tokens only. */ } directory_token_t; /* ********************************************************************** */ /** We use a table of rules to decide how to parse each token type. */ /** Rules for how many arguments a keyword can take. */ typedef enum { NO_ARGS, /**< (1) no arguments, ever */ ARGS, /**< (2) a list of arguments separated by spaces */ CONCAT_ARGS, /**< or (3) the rest of the line, treated as a single argument. */ } arg_syntax; /** Rules for whether the keyword needs an object. */ typedef enum { NO_OBJ, /**< (1) no object, ever */ NEED_OBJ, /**< (2) object is required */ NEED_KEY, /**< (3) object is required, and must be a public key. */ OBJ_OK, /**< or (4) object is optional. */ } obj_syntax; /** Rules for where a keyword can appear. */ typedef enum { ANY = 0, /**< Appears in router descriptor or in directory sections. */ DIR_ONLY, /**< Appears only in directory. */ RTR_ONLY, /**< Appears only in router descriptor or runningrouters */ } where_syntax; /** Table mapping keywords to token value and to argument rules. */ static struct { const char *t; int v; arg_syntax s; obj_syntax os; where_syntax ws; } token_table[] = { { "accept", K_ACCEPT, ARGS, NO_OBJ, RTR_ONLY }, { "directory-signature", K_DIRECTORY_SIGNATURE, ARGS, NEED_OBJ,DIR_ONLY}, { "reject", K_REJECT, ARGS, NO_OBJ, RTR_ONLY }, { "router", K_ROUTER, ARGS, NO_OBJ, RTR_ONLY }, { "recommended-software",K_RECOMMENDED_SOFTWARE,ARGS, NO_OBJ, DIR_ONLY }, { "signed-directory", K_SIGNED_DIRECTORY, NO_ARGS, NO_OBJ, DIR_ONLY }, { "signing-key", K_SIGNING_KEY, NO_ARGS, NEED_KEY,RTR_ONLY }, { "onion-key", K_ONION_KEY, NO_ARGS, NEED_KEY,RTR_ONLY }, { "router-signature", K_ROUTER_SIGNATURE, NO_ARGS, NEED_OBJ,RTR_ONLY }, { "running-routers", K_RUNNING_ROUTERS, ARGS, NO_OBJ, DIR_ONLY }, { "router-status", K_ROUTER_STATUS, ARGS, NO_OBJ, DIR_ONLY }, { "ports", K_PORTS, ARGS, NO_OBJ, RTR_ONLY }, { "bandwidth", K_BANDWIDTH, ARGS, NO_OBJ, RTR_ONLY }, { "platform", K_PLATFORM, CONCAT_ARGS, NO_OBJ, RTR_ONLY }, { "published", K_PUBLISHED, CONCAT_ARGS, NO_OBJ, ANY }, { "opt", K_OPT, CONCAT_ARGS, OBJ_OK, ANY }, { "contact", K_CONTACT, CONCAT_ARGS, NO_OBJ, ANY }, { "network-status", K_NETWORK_STATUS, NO_ARGS, NO_OBJ, DIR_ONLY }, { "uptime", K_UPTIME, ARGS, NO_OBJ, RTR_ONLY }, { "dir-signing-key", K_DIR_SIGNING_KEY, ARGS, OBJ_OK, DIR_ONLY }, { "family", K_FAMILY, ARGS, NO_OBJ, RTR_ONLY }, { "fingerprint", K_FINGERPRINT, ARGS, NO_OBJ, ANY }, { "hibernating", K_HIBERNATING, ARGS, NO_OBJ, RTR_ONLY }, { "read-history", K_READ_HISTORY, ARGS, NO_OBJ, RTR_ONLY }, { "write-history", K_WRITE_HISTORY, ARGS, NO_OBJ, RTR_ONLY }, { NULL, -1, NO_ARGS, NO_OBJ, ANY } }; /* static function prototypes */ static int router_add_exit_policy(routerinfo_t *router,directory_token_t *tok); static addr_policy_t *router_parse_addr_policy(directory_token_t *tok); static int router_get_hash_impl(const char *s, char *digest, const char *start_str, const char *end_str); static void token_free(directory_token_t *tok); static smartlist_t *find_all_exitpolicy(smartlist_t *s); static directory_token_t *find_first_by_keyword(smartlist_t *s, directory_keyword keyword); static int tokenize_string(const char *start, const char *end, smartlist_t *out, int is_dir); static directory_token_t *get_next_token(const char **s, where_syntax where); static int check_directory_signature(const char *digest, directory_token_t *tok, crypto_pk_env_t *pkey, crypto_pk_env_t *declared_key); static crypto_pk_env_t *find_dir_signing_key(const char *str); /* static */ int is_obsolete_version(const char *myversion, const char *versionlist); static int tor_version_same_series(tor_version_t *a, tor_version_t *b); /** Set digest to the SHA-1 digest of the hash of the directory in * s. Return 0 on success, nonzero on failure. */ int router_get_dir_hash(const char *s, char *digest) { return router_get_hash_impl(s,digest, "signed-directory","\ndirectory-signature"); } /** Set digest to the SHA-1 digest of the hash of the first router in * s. Return 0 on success, nonzero on failure. */ int router_get_router_hash(const char *s, char *digest) { return router_get_hash_impl(s,digest, "router ","\nrouter-signature"); } /** Set digest to the SHA-1 digest of the hash of the running-routers * string in s. Return 0 on success, nonzero on failure. */ int router_get_runningrouters_hash(const char *s, char *digest) { return router_get_hash_impl(s,digest, "network-status","\ndirectory-signature"); } /** * Find the first instance of "recommended-software ...\n" at the start of * a line; return a newly allocated string containing the "..." portion. * Return NULL if no such instance was found. */ static char * get_recommended_software_from_directory(const char *str) { #define REC "recommended-software " const char *cp = str, *eol; size_t len = strlen(REC); cp = str; if (strcmpstart(str, REC)==0) { cp += len; } else { cp = strstr(str, "\n"REC); if (!cp) return NULL; cp += len+1; } eol = strchr(cp, '\n'); if (!eol) return NULL; return tor_strndup(cp, eol-cp); #undef REC } /** Return 1 if myversion is not in versionlist, and if at least * one version of Tor on versionlist is newer than myversion. * Return 1 if no version from the same series as myversion is * in versionlist (and myversion is not the newest * version), or if a newer version from the same series is in * versionlist. * * Otherwise return 0. * (versionlist is a comma-separated list of version strings, * optionally prefixed with "Tor". Versions that can't be parsed are * ignored.) */ /* static */ int is_obsolete_version(const char *myversion, const char *versionlist) { const char *vl; tor_version_t mine, other; int found_newer = 0, found_newer_in_series = 0, found_any_in_series = 0, r, ret, same; static int warned_too_new=0; smartlist_t *version_sl; int XXXpath; vl = versionlist; log_fn(LOG_DEBUG,"Checking whether version '%s' is in '%s'", myversion, versionlist); if (tor_version_parse(myversion, &mine)) { log_fn(LOG_ERR, "I couldn't parse my own version (%s)", myversion); tor_assert(0); } version_sl = smartlist_create(); smartlist_split_string(version_sl, versionlist, ",", SPLIT_SKIP_SPACE, 0); SMARTLIST_FOREACH(version_sl, const char *, cp, { if (!strcmpstart(cp, "Tor ")) cp += 4; if (tor_version_parse(cp, &other)) { /* Couldn't parse other; it can't be a match. */ } else { same = tor_version_same_series(&mine, &other); if (same) found_any_in_series = 1; r = tor_version_compare(&mine, &other); if (r==0) { ret = 0; goto done; } else if (r<0) { found_newer = 1; if (same) found_newer_in_series = 1; } } }); /* We didn't find the listed version. Is it new or old? */ if (found_any_in_series) { if (!found_newer_in_series) { /* We belong to a series with recommended members, and we are newer than * any recommended member. We're probably okay. */ if (!warned_too_new) { log(LOG_WARN, "This version of Tor (%s) is newer than any in the same series on the recommended list (%s)", myversion, versionlist); warned_too_new = 1; } ret = 0; XXXpath = 1; } else { /* We found a newer one in the same series; we're obsolete. */ ret = 1; XXXpath = 2; } } else { if (found_newer) { /* We belong to a series with no recommended members, and * a newer series is recommended. We're obsolete. */ ret = 1; XXXpath = 3; } else { /* We belong to a series with no recommended members, and it's * newer than any recommended series. We're probably okay. */ if (!warned_too_new) { log(LOG_WARN, "This version of Tor (%s) is newer than any on the recommended list (%s)", myversion, versionlist); warned_too_new = 1; } ret = 0; XXXpath = 4; } } /* log_fn(LOG_DEBUG, "Decided that %s is %sobsolete relative to %s: %d, %d, %d\n", myversion, ret?"":"not ", versionlist, found_newer, found_any_in_series, found_newer_in_series); */ done: SMARTLIST_FOREACH(version_sl, char *, version, tor_free(version)); smartlist_free(version_sl); return ret; } /* Return 0 if myversion is supported; else log a message and return * -1 (or exit if ignoreversions is false) */ int check_software_version_against_directory(const char *directory) { char *v; v = get_recommended_software_from_directory(directory); if (!v) { log_fn(LOG_WARN, "No recommended-versions string found in directory"); return -1; } if (!is_obsolete_version(VERSION, v)) { tor_free(v); return 0; } log(LOG_WARN, "You are running Tor version %s, which will not work with this network.\n" "Please use %s%s.", VERSION, strchr(v,',') ? "one of " : "", v); tor_free(v); } /** Parse a directory from str and, when done, store the * resulting routerlist in *dest, freeing the old value if * necessary. * * If pkey is provided, we check the directory signature with pkey. * * If check_version is non-zero, then examine the * Recommended-versions * line in the directory, and warn or quit * as needed. * * If write_to_cache is non-zero, then store this directory in * memory and/or disk as well. */ int /* Should be static; exposed for unit tests */ router_parse_routerlist_from_directory(const char *str, routerlist_t **dest, crypto_pk_env_t *pkey, int check_version, int write_to_cache) { directory_token_t *tok; char digest[DIGEST_LEN]; routerlist_t *new_dir = NULL; char *versions = NULL; smartlist_t *good_nickname_list = NULL; time_t published_on; int i, r; const char *end, *cp; smartlist_t *tokens = NULL; char dirnickname[MAX_NICKNAME_LEN+1]; crypto_pk_env_t *declared_key = NULL; if (router_get_dir_hash(str, digest)) { log_fn(LOG_WARN, "Unable to compute digest of directory"); goto err; } log_fn(LOG_DEBUG,"Received directory hashes to %s",hex_str(digest,4)); /* Check signature first, before we try to tokenize. */ cp = str; while (cp && (end = strstr(cp+1, "\ndirectory-signature"))) cp = end; if (cp == str || !cp) { log_fn(LOG_WARN, "No signature found on directory."); goto err; } ++cp; tokens = smartlist_create(); if (tokenize_string(cp,strchr(cp,'\0'),tokens,1)) { log_fn(LOG_WARN, "Error tokenizing directory signature"); goto err; } if (smartlist_len(tokens) != 1) { log_fn(LOG_WARN, "Unexpected number of tokens in signature"); goto err; } tok=smartlist_get(tokens,0); if (tok->tp != K_DIRECTORY_SIGNATURE) { log_fn(LOG_WARN,"Expected a single directory signature"); goto err; } declared_key = find_dir_signing_key(str); if (check_directory_signature(digest, tok, pkey, declared_key)<0) goto err; /* now we know tok->n_args == 1, so it's safe to access tok->args[0] */ if (!is_legal_nickname(tok->args[0])) { log_fn(LOG_WARN, "Directory nickname '%s' is misformed", tok->args[0]); goto err; } strlcpy(dirnickname, tok->args[0], sizeof(dirnickname)); SMARTLIST_FOREACH(tokens, directory_token_t *, tok, token_free(tok)); smartlist_free(tokens); tokens = NULL; /* Now that we know the signature is okay, check the version. */ if (check_version) check_software_version_against_directory(str); /* Now try to parse the first part of the directory. */ if ((end = strstr(str,"\nrouter "))) { ++end; } else if ((end = strstr(str, "\ndirectory-signature"))) { ++end; } else { end = str + strlen(str); } tokens = smartlist_create(); if (tokenize_string(str,end,tokens,1)) { log_fn(LOG_WARN, "Error tokenizing directory"); goto err; } if (smartlist_len(tokens) < 1) { log_fn(LOG_WARN, "Impossibly short directory header"); goto err; } if ((tok = find_first_by_keyword(tokens, _UNRECOGNIZED))) { log_fn(LOG_WARN, "Unrecognized keyword \"%s\" in directory header; can't parse directory.", tok->args[0]); goto err; } tok = smartlist_get(tokens,0); if (tok->tp != K_SIGNED_DIRECTORY) { log_fn(LOG_WARN, "Directory doesn't start with signed-directory."); goto err; } if (!(tok = find_first_by_keyword(tokens, K_PUBLISHED))) { log_fn(LOG_WARN, "Missing published time on directory."); goto err; } tor_assert(tok->n_args == 1); if (parse_iso_time(tok->args[0], &published_on) < 0) { goto err; } /* Now that we know the signature is okay, and we have a * publication time, cache the directory. */ if (!get_options()->AuthoritativeDir && write_to_cache) dirserv_set_cached_directory(str, published_on, 0); if (!(tok = find_first_by_keyword(tokens, K_RECOMMENDED_SOFTWARE))) { log_fn(LOG_WARN, "Missing recommended-software line from directory."); goto err; } if (tok->n_args > 1) { log_fn(LOG_WARN, "Invalid recommended-software line"); goto err; } versions = tok->n_args ? tor_strdup(tok->args[0]) : tor_strdup(""); /* Prefer router-status, then running-routers. */ if (!(tok = find_first_by_keyword(tokens, K_ROUTER_STATUS))) { log_fn(LOG_WARN, "Missing router-status line from directory."); goto err; } good_nickname_list = smartlist_create(); for (i=0; in_args; ++i) { smartlist_add(good_nickname_list, tok->args[i]); } tok->n_args = 0; /* Don't free the strings in good_nickname_list yet. */ /* Read the router list from s, advancing s up past the end of the last * router. */ str = end; if (router_parse_list_from_string(&str, &new_dir, good_nickname_list, tok->tp==K_RUNNING_ROUTERS, published_on)) { log_fn(LOG_WARN, "Error reading routers from directory"); goto err; } /* Determine if my routerinfo is considered verified. */ { static int have_warned_about_unverified_status = 0; routerinfo_t *me = router_get_my_routerinfo(); if (me) { if (router_update_status_from_smartlist(me, published_on, good_nickname_list)==1 && me->is_verified == 0 && !have_warned_about_unverified_status) { log_fn(LOG_WARN,"Dirserver '%s' lists your server as unverified. Please consider sending your identity fingerprint to the tor-ops.", dirnickname); have_warned_about_unverified_status = 1; } } } new_dir->software_versions = versions; versions = NULL; new_dir->published_on = published_on; new_dir->running_routers = tor_malloc_zero(sizeof(running_routers_t)); new_dir->running_routers->published_on = published_on; new_dir->running_routers->running_routers = good_nickname_list; SMARTLIST_FOREACH(tokens, directory_token_t *, tok, token_free(tok)); smartlist_free(tokens); tokens = NULL; if (*dest) routerlist_free(*dest); *dest = new_dir; r = 0; goto done; err: r = -1; if (new_dir) routerlist_free(new_dir); tor_free(versions); if (good_nickname_list) { SMARTLIST_FOREACH(good_nickname_list, char *, n, tor_free(n)); smartlist_free(good_nickname_list); } done: if (declared_key) crypto_free_pk_env(declared_key); if (tokens) { SMARTLIST_FOREACH(tokens, directory_token_t *, tok, token_free(tok)); smartlist_free(tokens); } return r; } /** Read a signed router status statement from str. On * success, return it, and cache the original string if * write_to_cache is set. Otherwise, return NULL. */ running_routers_t * router_parse_runningrouters(const char *str, int write_to_cache) { char digest[DIGEST_LEN]; running_routers_t *new_list = NULL; directory_token_t *tok; time_t published_on; int i; crypto_pk_env_t *declared_key = NULL; smartlist_t *tokens = NULL; if (router_get_runningrouters_hash(str, digest)) { log_fn(LOG_WARN, "Unable to compute digest of directory"); goto err; } tokens = smartlist_create(); if (tokenize_string(str,str+strlen(str),tokens,1)) { log_fn(LOG_WARN, "Error tokenizing directory"); goto err; } if ((tok = find_first_by_keyword(tokens, _UNRECOGNIZED))) { log_fn(LOG_WARN, "Unrecognized keyword '%s'; can't parse running-routers", tok->args[0]); goto err; } tok = smartlist_get(tokens,0); if (tok->tp != K_NETWORK_STATUS) { log_fn(LOG_WARN, "Network-status starts with wrong token"); goto err; } if (!(tok = find_first_by_keyword(tokens, K_PUBLISHED))) { log_fn(LOG_WARN, "Missing published time on directory."); goto err; } tor_assert(tok->n_args == 1); if (parse_iso_time(tok->args[0], &published_on) < 0) { goto err; } /* Now that we know the signature is okay, and we have a * publication time, cache the list. */ if (!get_options()->AuthoritativeDir && write_to_cache) dirserv_set_cached_directory(str, published_on, 1); if (!(tok = find_first_by_keyword(tokens, K_ROUTER_STATUS))) { if (!(tok = find_first_by_keyword(tokens, K_RUNNING_ROUTERS))) { log_fn(LOG_WARN, "Missing running-routers/router-status line from directory."); goto err; } } new_list = tor_malloc_zero(sizeof(running_routers_t)); new_list->published_on = published_on; new_list->running_routers = smartlist_create(); for (i=0;in_args;++i) { smartlist_add(new_list->running_routers, tok->args[i]); } tok->n_args = 0; /* Don't free the elements of tok->args. */ if (!(tok = find_first_by_keyword(tokens, K_DIRECTORY_SIGNATURE))) { log_fn(LOG_WARN, "Missing signature on running-routers"); goto err; } declared_key = find_dir_signing_key(str); if (check_directory_signature(digest, tok, NULL, declared_key) < 0) goto err; goto done; err: if (new_list) { running_routers_free(new_list); new_list = NULL; } done: if (declared_key) crypto_free_pk_env(declared_key); if (tokens) { SMARTLIST_FOREACH(tokens, directory_token_t *, tok, token_free(tok)); smartlist_free(tokens); } return new_list; } /** Given a directory or running-routers string in str, try to * find the its dir-signing-key token (if any). If this token is * present, extract and return the key. Return NULL on failure. */ static crypto_pk_env_t * find_dir_signing_key(const char *str) { const char *cp; directory_token_t *tok; crypto_pk_env_t *key = NULL; /* Is there a dir-signing-key in the directory? */ cp = strstr(str, "\nopt dir-signing-key"); if (!cp) cp = strstr(str, "\ndir-signing-key"); if (!cp) return NULL; ++cp; /* Now cp points to the start of the token. */ tok = get_next_token(&cp, DIR_ONLY); if (!tok) { log_fn(LOG_WARN, "Unparseable dir-signing-key token"); return NULL; } if (tok->tp != K_DIR_SIGNING_KEY) { log_fn(LOG_WARN, "Dir-signing-key token did not parse as expected"); return NULL; } if (tok->key) { key = tok->key; tok->key = NULL; /* steal reference. */ } else if (tok->n_args >= 1) { /** XXXX Once all the directories are running 0.1.0.6-rc or later, we * can remove this logic. */ key = crypto_pk_DER64_decode_public_key(tok->args[0]); if (!key) { log_fn(LOG_WARN, "Unparseable dir-signing-key argument"); return NULL; } } else { log_fn(LOG_WARN, "Dir-signing-key token contained no key"); return NULL; } token_free(tok); return key; } /** Return true iff key is allowed to sign directories. */ static int dir_signing_key_is_trusted(crypto_pk_env_t *key) { char digest[DIGEST_LEN]; if (!key) return 0; if (crypto_pk_get_digest(key, digest) < 0) { log_fn(LOG_WARN, "Error computing dir-signing-key digest"); return 0; } if (!router_digest_is_trusted_dir(digest)) { log_fn(LOG_WARN, "Listed dir-signing-key is not trusted"); return 0; } return 1; } /** Check whether the K_DIRECTORY_SIGNATURE token in tok has a * good signature for digest. * * If declared_key is set, the directory has declared what key * was used to sign it, so we will use that key only if it is an * authoritative directory signing key. * * Otherwise, if pkey is provided, try to use it. * * (New callers should always use declared_key when possible; * pkey is only for debugging.) */ static int check_directory_signature(const char *digest, directory_token_t *tok, crypto_pk_env_t *pkey, crypto_pk_env_t *declared_key) { char signed_digest[PK_BYTES]; crypto_pk_env_t *_pkey = NULL; if (tok->n_args != 1) { log_fn(LOG_WARN, "Too many or too few arguments to directory-signature"); return -1; } if (declared_key) { if (dir_signing_key_is_trusted(declared_key)) _pkey = declared_key; } if (!_pkey && pkey) { /* pkey provided for debugging purposes */ _pkey = pkey; } if (!_pkey) { log_fn(LOG_WARN, "Obsolete directory format (dir signing key not present) or signing key not trusted--rejecting."); return -1; } if (strcmp(tok->object_type, "SIGNATURE") || tok->object_size != 128) { log_fn(LOG_WARN, "Bad object type or length on directory signature"); return -1; } tor_assert(_pkey); if (crypto_pk_public_checksig(_pkey, signed_digest, tok->object_body, 128) != 20) { log_fn(LOG_WARN, "Error reading directory: invalid signature."); return -1; } log_fn(LOG_DEBUG,"Signed directory hash starts %s", hex_str(signed_digest,4)); if (memcmp(digest, signed_digest, 20)) { log_fn(LOG_WARN, "Error reading directory: signature does not match."); return -1; } return 0; } /** Given a string *s containing a concatenated sequence of router * descriptors, parses them and stores the result in *dest. If * good_nickname_list is provided, then routers are marked as * running/nonrunning and verified/unverified based on their status in the * list. Otherwise, all routers are marked running and verified. Advances * *s to a point immediately following the last router entry. Returns 0 on * success and -1 on failure. */ int router_parse_list_from_string(const char **s, routerlist_t **dest, smartlist_t *good_nickname_list, int rr_format, time_t published_on) { routerinfo_t *router; smartlist_t *routers; const char *end; tor_assert(s); tor_assert(*s); routers = smartlist_create(); while (1) { *s = eat_whitespace(*s); /* Don't start parsing the rest of *s unless it contains a router. */ if (strcmpstart(*s, "router ")!=0) break; if ((end = strstr(*s+1, "\nrouter "))) { end++; } else if ((end = strstr(*s+1, "\ndirectory-signature"))) { end++; } else { end = *s+strlen(*s); } router = router_parse_entry_from_string(*s, end); *s = end; if (!router) { log_fn(LOG_WARN, "Error reading router; skipping"); continue; } if (!good_nickname_list) { router->is_running = 1; /* start out assuming all dirservers are up */ router->is_verified = 1; router->status_set_at = time(NULL); } smartlist_add(routers, router); // log_fn(LOG_DEBUG,"just added router #%d.",smartlist_len(routers)); } if (good_nickname_list) { SMARTLIST_FOREACH(good_nickname_list, const char *, cp, routers_update_status_from_entry(routers, published_on, cp)); } if (*dest) routerlist_free(*dest); *dest = tor_malloc_zero(sizeof(routerlist_t)); (*dest)->routers = routers; return 0; } /** Helper function: reads a single router entry from *s ... * *end. Mallocs a new router and returns it if all goes well, else * returns NULL. */ routerinfo_t * router_parse_entry_from_string(const char *s, const char *end) { routerinfo_t *router = NULL; char signed_digest[128]; char digest[128]; smartlist_t *tokens = NULL, *exit_policy_tokens = NULL; directory_token_t *tok; int t; int ports_set, bw_set; if (!end) { end = s + strlen(s); } if (router_get_router_hash(s, digest) < 0) { log_fn(LOG_WARN, "Couldn't compute router hash."); return NULL; } tokens = smartlist_create(); if (tokenize_string(s,end,tokens,0)) { log_fn(LOG_WARN, "Error tokeninzing router descriptor."); goto err; } if (smartlist_len(tokens) < 2) { log_fn(LOG_WARN, "Impossibly short router descriptor."); goto err; } if ((tok = find_first_by_keyword(tokens, _UNRECOGNIZED))) { log_fn(LOG_INFO, "Unrecognized critical keyword '%s'; skipping descriptor. (It may be from another version of Tor.)", tok->args[0]); goto err; } tok = smartlist_get(tokens,0); if (tok->tp != K_ROUTER) { log_fn(LOG_WARN,"Entry does not start with \"router\""); goto err; } router = tor_malloc_zero(sizeof(routerinfo_t)); router->signed_descriptor = tor_strndup(s, end-s); ports_set = bw_set = 0; if (tok->n_args == 2 || tok->n_args == 5 || tok->n_args == 6) { router->nickname = tor_strdup(tok->args[0]); if (!is_legal_nickname(router->nickname)) { log_fn(LOG_WARN,"Router nickname is invalid"); goto err; } router->address = tor_strdup(tok->args[1]); router->addr = 0; if (tok->n_args >= 5) { router->or_port = (uint16_t) tor_parse_long(tok->args[2],10,0,65535,NULL,NULL); router->dir_port = (uint16_t) tor_parse_long(tok->args[4],10,0,65535,NULL,NULL); ports_set = 1; } } else { log_fn(LOG_WARN,"Wrong # of arguments to \"router\" (%d)",tok->n_args); goto err; } tok = find_first_by_keyword(tokens, K_PORTS); if (tok && ports_set) { log_fn(LOG_WARN,"Redundant ports line"); goto err; } else if (tok) { if (tok->n_args != 3) { log_fn(LOG_WARN,"Wrong # of arguments to \"ports\""); goto err; } router->or_port = (uint16_t) tor_parse_long(tok->args[0],10,0,65535,NULL,NULL); router->dir_port = (uint16_t) tor_parse_long(tok->args[2],10,0,65535,NULL,NULL); ports_set = 1; } tok = find_first_by_keyword(tokens, K_BANDWIDTH); if (tok && bw_set) { log_fn(LOG_WARN,"Redundant bandwidth line"); goto err; } else if (tok) { if (tok->n_args < 3) { /* XXXX Once 0.0.7 is *really* dead, restore this warning to its old form*/ log_fn(LOG_WARN,"Not enough arguments to \"bandwidth\": must be an obsolete server. Rejecting one server (nickname '%s').", router->nickname); goto err; } router->bandwidthrate = tor_parse_long(tok->args[0],10,0,INT_MAX,NULL,NULL); router->bandwidthburst = tor_parse_long(tok->args[1],10,0,INT_MAX,NULL,NULL); router->bandwidthcapacity = tor_parse_long(tok->args[2],10,0,INT_MAX,NULL,NULL); bw_set = 1; } if ((tok = find_first_by_keyword(tokens, K_UPTIME))) { if (tok->n_args != 1) { log_fn(LOG_WARN, "Unrecognized number of args on K_UPTIME; skipping."); } else { router->uptime = tor_parse_long(tok->args[0],10,0,LONG_MAX,NULL,NULL); } } if (!(tok = find_first_by_keyword(tokens, K_PUBLISHED))) { log_fn(LOG_WARN, "Missing published time"); goto err; } tor_assert(tok->n_args == 1); if (parse_iso_time(tok->args[0], &router->published_on) < 0) goto err; if (!(tok = find_first_by_keyword(tokens, K_ONION_KEY))) { log_fn(LOG_WARN, "Missing onion key"); goto err; } if (crypto_pk_keysize(tok->key) != PK_BYTES) { log_fn(LOG_WARN, "Wrong size on onion key: %d bits!", (int)crypto_pk_keysize(tok->key)*8); goto err; } router->onion_pkey = tok->key; tok->key = NULL; /* Prevent free */ if (!(tok = find_first_by_keyword(tokens, K_SIGNING_KEY))) { log_fn(LOG_WARN, "Missing identity key"); goto err; } if (crypto_pk_keysize(tok->key) != PK_BYTES) { log_fn(LOG_WARN, "Wrong size on identity key: %d bits!", (int)crypto_pk_keysize(tok->key)*8); goto err; } router->identity_pkey = tok->key; tok->key = NULL; /* Prevent free */ if (crypto_pk_get_digest(router->identity_pkey,router->identity_digest)) { log_fn(LOG_WARN, "Couldn't calculate key digest"); goto err; } if ((tok = find_first_by_keyword(tokens, K_PLATFORM))) { router->platform = tor_strdup(tok->args[0]); } if ((tok = find_first_by_keyword(tokens, K_CONTACT))) { router->contact_info = tor_strdup(tok->args[0]); } exit_policy_tokens = find_all_exitpolicy(tokens); SMARTLIST_FOREACH(exit_policy_tokens, directory_token_t *, t, if (router_add_exit_policy(router,t)<0) { log_fn(LOG_WARN,"Error in exit policy"); goto err; }); if ((tok = find_first_by_keyword(tokens, K_FAMILY)) && tok->n_args) { int i; router->declared_family = smartlist_create(); for (i=0;in_args;++i) { if (!is_legal_nickname_or_hexdigest(tok->args[i])) { log_fn(LOG_WARN, "Illegal nickname '%s' in family line", tok->args[i]); goto err; } smartlist_add(router->declared_family, tor_strdup(tok->args[i])); } } if (!(tok = find_first_by_keyword(tokens, K_ROUTER_SIGNATURE))) { log_fn(LOG_WARN, "Missing router signature"); goto err; } if (strcmp(tok->object_type, "SIGNATURE") || tok->object_size != 128) { log_fn(LOG_WARN, "Bad object type or length on router signature"); goto err; } if ((t=crypto_pk_public_checksig(router->identity_pkey, signed_digest, tok->object_body, 128)) != 20) { log_fn(LOG_WARN, "Invalid signature %d",t); goto err; } if (memcmp(digest, signed_digest, 20)) { log_fn(LOG_WARN, "Mismatched signature"); goto err; } if (!ports_set) { log_fn(LOG_WARN,"No ports declared; failing."); goto err; } if (!bw_set) { log_fn(LOG_WARN,"No bandwidth declared; failing."); goto err; } if (!router->or_port) { log_fn(LOG_WARN,"or_port unreadable or 0. Failing."); goto err; } if (!router->bandwidthrate) { log_fn(LOG_WARN,"bandwidthrate unreadable or 0. Failing."); goto err; } if (!router->platform) { router->platform = tor_strdup(""); } goto done; return router; err: routerinfo_free(router); router = NULL; done: if (tokens) { SMARTLIST_FOREACH(tokens, directory_token_t *, tok, token_free(tok)); smartlist_free(tokens); } if (exit_policy_tokens) { smartlist_free(exit_policy_tokens); } return router; } /** Parse the exit policy in the string s and return it. If * assume_action is nonnegative, then insert its action (ADDR_POLICY_ACCEPT or * ADDR_POLICY_REJECT) for items that specify no action. */ addr_policy_t * router_parse_addr_policy_from_string(const char *s, int assume_action) { directory_token_t *tok = NULL; const char *cp; char *tmp; addr_policy_t *r; size_t len, idx; /* *s might not end with \n, so we need to extend it with one. */ len = strlen(s); cp = tmp = tor_malloc(len+2); for (idx = 0; idx < len; ++idx) { tmp[idx] = tolower(s[idx]); } tmp[len]='\n'; tmp[len+1]='\0'; while (TOR_ISSPACE(*cp)) ++cp; if ((*cp == '*' || TOR_ISDIGIT(*cp)) && assume_action >= 0) { char *new_str = tor_malloc(len+10); tor_snprintf(new_str, len+10, "%s %s\n", assume_action == ADDR_POLICY_ACCEPT?"accept":"reject", cp); tor_free(tmp); cp = tmp = new_str; } tok = get_next_token(&cp, RTR_ONLY); if (tok->tp == _ERR) { log_fn(LOG_WARN, "Error reading exit policy: %s", tok->error); goto err; } if (tok->tp != K_ACCEPT && tok->tp != K_REJECT) { log_fn(LOG_WARN, "Expected 'accept' or 'reject'."); goto err; } /* Now that we've gotten an exit policy, add it to the router. */ r = router_parse_addr_policy(tok); goto done; err: r = NULL; done: tor_free(tmp); token_free(tok); return r; } /** DOCDOC */ int router_add_exit_policy_from_string(routerinfo_t *router, const char *s) { addr_policy_t *newe, *tmpe; newe = router_parse_addr_policy_from_string(s, -1); if (!newe) return -1; for (tmpe = router->exit_policy; tmpe; tmpe=tmpe->next) ; tmpe->next = newe; return 0; } /** DOCDOC */ static int router_add_exit_policy(routerinfo_t *router,directory_token_t *tok) { addr_policy_t *newe, **tmpe; newe = router_parse_addr_policy(tok); if (!newe) return -1; for (tmpe = &router->exit_policy; *tmpe; tmpe=&((*tmpe)->next)) ; *tmpe = newe; return 0; } /** Given a K_ACCEPT or K_REJECT token and a router, create and return * a new exit_policy_t corresponding to the token. */ static addr_policy_t * router_parse_addr_policy(directory_token_t *tok) { addr_policy_t *newe; // struct in_addr in; char *arg; // char *address; // char buf[INET_NTOA_BUF_LEN]; tor_assert(tok->tp == K_REJECT || tok->tp == K_ACCEPT); if (tok->n_args != 1) return NULL; arg = tok->args[0]; newe = tor_malloc_zero(sizeof(addr_policy_t)); newe->string = tor_malloc(8+strlen(arg)); /* XXX eventually, use the code from router.c:727 to generate this */ tor_snprintf(newe->string, 8+strlen(arg), "%s %s", (tok->tp == K_REJECT) ? "reject" : "accept", arg); newe->policy_type = (tok->tp == K_REJECT) ? ADDR_POLICY_REJECT : ADDR_POLICY_ACCEPT; if (parse_addr_and_port_range(arg, &newe->addr, &newe->msk, &newe->prt_min, &newe->prt_max)) goto policy_read_failed; // in.s_addr = htonl(newe->addr); // tor_inet_ntoa(&in, buf, sizeof(buf)); // address = tor_strdup(buf); // in.s_addr = htonl(newe->msk); // log_fn(LOG_DEBUG,"%s %s/%s:%d-%d", // newe->policy_type == ADDR_POLICY_REJECT ? "reject" : "accept", // address, inet_ntoa(in), newe->prt_min, newe->prt_max); // tor_free(address); return newe; policy_read_failed: tor_assert(newe->string); log_fn(LOG_WARN,"Couldn't parse line '%s'. Dropping", newe->string); tor_free(newe->string); tor_free(newe); return NULL; } /** log and exit if t is malformed */ void assert_addr_policy_ok(addr_policy_t *t) { addr_policy_t *t2; while (t) { tor_assert(t->policy_type == ADDR_POLICY_REJECT || t->policy_type == ADDR_POLICY_ACCEPT); tor_assert(t->prt_min <= t->prt_max); t2 = router_parse_addr_policy_from_string(t->string, -1); tor_assert(t2); tor_assert(t2->policy_type == t->policy_type); tor_assert(t2->addr == t->addr); tor_assert(t2->msk == t->msk); tor_assert(t2->prt_min == t->prt_min); tor_assert(t2->prt_max == t->prt_max); tor_assert(!strcmp(t2->string, t->string)); tor_assert(t2->next == NULL); addr_policy_free(t2); t = t->next; } } /* * Low-level tokenizer for router descriptors and directories. */ /** Free all resources allocated for tok */ static void token_free(directory_token_t *tok) { int i; tor_assert(tok); if (tok->args) { for (i = 0; i < tok->n_args; ++i) { tor_free(tok->args[i]); } tor_free(tok->args); } tor_free(tok->object_type); tor_free(tok->object_body); if (tok->key) crypto_free_pk_env(tok->key); tor_free(tok); } /** Helper function: read the next token from *s, advance *s to the end * of the token, and return the parsed token. If 'where' is DIR_ONLY * or RTR_ONLY, reject all tokens of the wrong type. */ static directory_token_t * get_next_token(const char **s, where_syntax where) { const char *next, *obstart; int i, done, allocated, is_opt; directory_token_t *tok; arg_syntax a_syn; obj_syntax o_syn = NO_OBJ; #define RET_ERR(msg) \ do { if (tok) token_free(tok); \ tok = tor_malloc_zero(sizeof(directory_token_t));\ tok->tp = _ERR; \ tok->error = msg; \ goto done_tokenizing; } while (0) tok = tor_malloc_zero(sizeof(directory_token_t)); tok->tp = _ERR; *s = eat_whitespace(*s); if (!**s) { tok->tp = _EOF; return tok; } next = find_whitespace(*s); if (!next) { tok->error = "Unexpected EOF"; return tok; } /* It's a keyword... but which one? */ is_opt = !strncmp("opt", *s, next-*s); if (is_opt) { *s = eat_whitespace(next); next = NULL; if (**s) next = find_whitespace(*s); if (!**s || !next) { RET_ERR("opt without keyword"); } } for (i = 0; token_table[i].t ; ++i) { if (!strncmp(token_table[i].t, *s, next-*s)) { /* We've found the keyword. */ tok->tp = token_table[i].v; a_syn = token_table[i].s; o_syn = token_table[i].os; if (token_table[i].ws != ANY && token_table[i].ws != where) { if (where == DIR_ONLY) { RET_ERR("Found a router-only token in a directory section"); } else { RET_ERR("Found a directory-only token in a router descriptor"); } } if (a_syn == ARGS) { /* This keyword takes multiple arguments. */ i = 0; done = (*next == '\n'); allocated = 32; tok->args = tor_malloc(sizeof(char*)*32); *s = eat_whitespace_no_nl(next); while (**s != '\n' && !done) { next = find_whitespace(*s); if (*next == '\n') done = 1; if (i == allocated) { allocated *= 2; tok->args = tor_realloc(tok->args,sizeof(char*)*allocated); } tok->args[i++] = tor_strndup(*s,next-*s); *s = eat_whitespace_no_nl(next+1); } tok->n_args = i; } else if (a_syn == CONCAT_ARGS) { /* The keyword takes the line as a single argument */ *s = eat_whitespace_no_nl(next); next = strchr(*s, '\n'); if (!next) RET_ERR("Unexpected EOF"); tok->args = tor_malloc(sizeof(char*)); tok->args[0] = tor_strndup(*s,next-*s); tok->n_args = 1; *s = eat_whitespace_no_nl(next+1); } else { /* The keyword takes no arguments. */ tor_assert(a_syn == NO_ARGS); *s = eat_whitespace_no_nl(next); if (**s != '\n') { RET_ERR("Unexpected arguments"); } tok->n_args = 0; *s = eat_whitespace_no_nl(*s+1); } break; } } if (tok->tp == _ERR) { if (is_opt) { tok->tp = K_OPT; *s = eat_whitespace_no_nl(next); next = strchr(*s,'\n'); if (!next) RET_ERR("Unexpected EOF"); tok->args = tor_malloc(sizeof(char*)); tok->args[0] = tor_strndup(*s,next-*s); tok->n_args = 1; *s = eat_whitespace_no_nl(next+1); o_syn = OBJ_OK; } else { tok->tp = _UNRECOGNIZED; next = strchr(*s, '\n'); if (!next) { RET_ERR("Unexpected EOF"); } tok->args = tor_malloc(sizeof(char*)); tok->args[0] = tor_strndup(*s,next-*s); tok->n_args = 1; *s = next+1; o_syn = OBJ_OK; } } *s = eat_whitespace(*s); if (strcmpstart(*s, "-----BEGIN ")) { goto done_tokenizing; } obstart = *s; *s += 11; /* length of "-----BEGIN ". */ next = strchr(*s, '\n'); if (next-*s < 6 || strcmpstart(next-5, "-----\n")) { RET_ERR("Malformed object: bad begin line"); } tok->object_type = tor_strndup(*s, next-*s-5); *s = next+1; next = strstr(*s, "-----END "); if (!next) { RET_ERR("Malformed object: missing end line"); } if (!strcmp(tok->object_type, "RSA PUBLIC KEY")) { if (strcmpstart(next, "-----END RSA PUBLIC KEY-----\n")) RET_ERR("Malformed object: mismatched end line"); next = strchr(next,'\n')+1; tok->key = crypto_new_pk_env(); if (crypto_pk_read_public_key_from_string(tok->key, obstart, next-obstart)) RET_ERR("Couldn't parse public key."); *s = next; } else { tok->object_body = tor_malloc(next-*s); /* really, this is too much RAM. */ i = base64_decode(tok->object_body, 256, *s, next-*s); if (i<0) { RET_ERR("Malformed object: bad base64-encoded data"); } tok->object_size = i; *s = next + 9; /* length of "-----END ". */ i = strlen(tok->object_type); if (strncmp(*s, tok->object_type, i) || strcmpstart(*s+i, "-----\n")) { RET_ERR("Malformed object: mismatched end tag"); } *s += i+6; } switch (o_syn) { case NO_OBJ: if (tok->object_body) RET_ERR("Unexpected object for keyword"); if (tok->key) RET_ERR("Unexpected public key for keyword"); break; case NEED_OBJ: if (!tok->object_body) RET_ERR("Missing object for keyword"); break; case NEED_KEY: if (!tok->key) RET_ERR("Missing public key for keyword"); break; case OBJ_OK: break; } done_tokenizing: return tok; #undef RET_ERR } /** Read all tokens from a string between start and end, and add * them to out. If is_dir is true, reject all non-directory * tokens; else reject all non-routerdescriptor tokens. */ static int tokenize_string(const char *start, const char *end, smartlist_t *out, int is_dir) { const char **s; directory_token_t *tok = NULL; where_syntax where = is_dir ? DIR_ONLY : RTR_ONLY; s = &start; while (*s < end && (!tok || tok->tp != _EOF)) { tok = get_next_token(s, where); if (tok->tp == _ERR) { log_fn(LOG_WARN, "parse error: %s", tok->error); return -1; } smartlist_add(out, tok); *s = eat_whitespace(*s); } return 0; } /** Find the first token in s whose keyword is keyword; return * NULL if no such keyword is found. */ static directory_token_t * find_first_by_keyword(smartlist_t *s, directory_keyword keyword) { SMARTLIST_FOREACH(s, directory_token_t *, t, if (t->tp == keyword) return t); return NULL; } /** Return a newly allocated smartlist of all accept or reject tokens in * s. */ static smartlist_t * find_all_exitpolicy(smartlist_t *s) { smartlist_t *out = smartlist_create(); SMARTLIST_FOREACH(s, directory_token_t *, t, if (t->tp == K_ACCEPT || t->tp == K_REJECT) smartlist_add(out,t)); return out; } /** Compute the SHA digest of the substring of s taken from the first * occurrence of start_str through the first newline after the first * subsequent occurrence of end_str; store the 20-byte result in * digest; return 0 on success. * * If no such substring exists, return -1. */ static int router_get_hash_impl(const char *s, char *digest, const char *start_str, const char *end_str) { char *start, *end; start = strstr(s, start_str); if (!start) { log_fn(LOG_WARN,"couldn't find \"%s\"",start_str); return -1; } if (start != s && *(start-1) != '\n') { log_fn(LOG_WARN, "first occurrence of \"%s\" is not at the start of a line", start_str); return -1; } end = strstr(start+strlen(start_str), end_str); if (!end) { log_fn(LOG_WARN,"couldn't find \"%s\"",end_str); return -1; } end = strchr(end+strlen(end_str), '\n'); if (!end) { log_fn(LOG_WARN,"couldn't find EOL"); return -1; } ++end; if (crypto_digest(digest, start, end-start)) { log_fn(LOG_WARN,"couldn't compute digest"); return -1; } return 0; } /** Parse the Tor version of the platform string platform, * and compare it to the version in cutoff. Return 1 if * the router is at least as new as the cutoff, else return 0. */ int tor_version_as_new_as(const char *platform, const char *cutoff) { tor_version_t cutoff_version, router_version; char *s, *start; char tmp[128]; if (tor_version_parse(cutoff, &cutoff_version)<0) { log_fn(LOG_WARN,"Bug: cutoff version '%s' unparseable.",cutoff); return 0; } if (strcmpstart(platform,"Tor ")) /* nonstandard Tor; be safe and say yes */ return 1; start = (char *)eat_whitespace(platform+3); if (!*start) return 0; s = (char *)find_whitespace(start); /* also finds '\0', which is fine */ if ((size_t)(s-start+1) >= sizeof(tmp)) /* too big, no */ return 0; strlcpy(tmp, start, s-start+1); if (tor_version_parse(tmp, &router_version)<0) { log_fn(LOG_INFO,"Router version '%s' unparseable.",tmp); return 1; /* be safe and say yes */ } return tor_version_compare(&router_version, &cutoff_version) >= 0; } /** Parse a tor version from s, and store the result in out. * Return 0 on success, -1 on failure. */ int tor_version_parse(const char *s, tor_version_t *out) { char *eos=NULL, *cp=NULL; /* Format is: * "Tor " ? NUM dot NUM dot NUM [ ( pre | rc | dot ) NUM [ -cvs ] ] */ tor_assert(s); tor_assert(out); memset(out, 0, sizeof(tor_version_t)); if (!strcasecmpstart(s, "Tor ")) cp += 4; /* Get major. */ out->major = strtol(s,&eos,10); if (!eos || eos==s || *eos != '.') return -1; cp = eos+1; /* Get minor */ out->minor = strtol(cp,&eos,10); if (!eos || eos==cp || *eos != '.') return -1; cp = eos+1; /* Get micro */ out->micro = strtol(cp,&eos,10); if (!eos || eos==cp) return -1; if (!*eos) { out->status = VER_RELEASE; out->patchlevel = 0; out->cvs = IS_NOT_CVS; return 0; } cp = eos; /* Get status */ if (*cp == '.') { out->status = VER_RELEASE; ++cp; } else if (0==strncmp(cp, "pre", 3)) { out->status = VER_PRE; cp += 3; } else if (0==strncmp(cp, "rc", 2)) { out->status = VER_RC; cp += 2; } else { return -1; } /* Get patchlevel */ out->patchlevel = strtol(cp,&eos,10); if (!eos || eos==cp) return -1; cp = eos; /* Get cvs status and status tag. */ if (*cp == '-' || *cp == '.') ++cp; strlcpy(out->status_tag, cp, sizeof(out->status_tag)); if (0==strcmp(cp, "cvs")) { out->cvs = IS_CVS; } else { out->cvs = IS_NOT_CVS; } return 0; } /** Compare two tor versions; Return <0 if a < b; 0 if a ==b, >0 if a > * b. */ int tor_version_compare(tor_version_t *a, tor_version_t *b) { int i; tor_assert(a); tor_assert(b); if ((i = a->major - b->major)) return i; else if ((i = a->minor - b->minor)) return i; else if ((i = a->micro - b->micro)) return i; else if ((i = a->status - b->status)) return i; else if ((i = a->patchlevel - b->patchlevel)) return i; if (a->major > 0 || a->minor > 0) { return strcmp(a->status_tag, b->status_tag); } else { return (a->cvs - b->cvs); } } /** Return true iff versions a and b belong to the same series. */ static int tor_version_same_series(tor_version_t *a, tor_version_t *b) { tor_assert(a); tor_assert(b); return ((a->major == b->major) && (a->minor == b->minor) && (a->micro == b->micro)); }