/* Copyright 2001-2004 Roger Dingledine. * Copyright 2004-2006 Roger Dingledine, Nick Mathewson. */ /* See LICENSE for licensing information */ /* $Id$ */ const char directory_c_id[] = "$Id$"; #include "or.h" /** * \file directory.c * \brief Code to send and fetch directories and router * descriptors via HTTP. Directories use dirserv.c to generate the * results; clients use routers.c to parse them. **/ /* In-points to directory.c: * * - directory_post_to_dirservers(), called from * router_upload_dir_desc_to_dirservers() in router.c * upload_service_descriptor() in rendservice.c * - directory_get_from_dirserver(), called from * rend_client_refetch_renddesc() in rendclient.c * run_scheduled_events() in main.c * do_hup() in main.c * - connection_dir_process_inbuf(), called from * connection_process_inbuf() in connection.c * - connection_dir_finished_flushing(), called from * connection_finished_flushing() in connection.c * - connection_dir_finished_connecting(), called from * connection_finished_connecting() in connection.c */ static void directory_initiate_command(const char *address, uint32_t addr, uint16_t port, const char *platform, const char *digest, uint8_t purpose, int private_connection, const char *resource, const char *payload, size_t payload_len); static void directory_send_command(dir_connection_t *conn, const char *platform, int purpose, int direct, const char *resource, const char *payload, size_t payload_len); static int directory_handle_command(dir_connection_t *conn); static int body_is_plausible(const char *body, size_t body_len, int purpose); static int purpose_is_private(uint8_t purpose); static char *http_get_header(const char *headers, const char *which); static void http_set_address_origin(const char *headers, connection_t *conn); static void connection_dir_download_networkstatus_failed( dir_connection_t *conn, int status_code); static void connection_dir_download_routerdesc_failed(dir_connection_t *conn); static void dir_networkstatus_download_failed(smartlist_t *failed, int status_code); static void dir_routerdesc_download_failed(smartlist_t *failed, int status_code); static void note_request(const char *key, size_t bytes); /********* START VARIABLES **********/ /** How far in the future do we allow a directory server to tell us it is * before deciding that one of us has the wrong time? */ #define ALLOW_DIRECTORY_TIME_SKEW (30*60) #define X_ADDRESS_HEADER "X-Your-Address-Is: " /* HTTP cache control: how long do we tell proxies they can cache things? */ #define FULL_DIR_CACHE_LIFETIME (60*60) #define RUNNINGROUTERS_CACHE_LIFETIME (20*60) #define NETWORKSTATUS_CACHE_LIFETIME (5*60) #define ROUTERDESC_CACHE_LIFETIME (30*60) #define ROUTERDESC_BY_DIGEST_CACHE_LIFETIME (48*60*60) #define ROBOTS_CACHE_LIFETIME (24*60*60) /********* END VARIABLES ************/ /** Return true iff the directory purpose 'purpose' must use an * anonymous connection to a directory. */ static int purpose_is_private(uint8_t purpose) { if (get_options()->AllDirActionsPrivate) return 1; if (purpose == DIR_PURPOSE_FETCH_DIR || purpose == DIR_PURPOSE_UPLOAD_DIR || purpose == DIR_PURPOSE_FETCH_RUNNING_LIST || purpose == DIR_PURPOSE_FETCH_NETWORKSTATUS || purpose == DIR_PURPOSE_FETCH_SERVERDESC) return 0; return 1; } /** Start a connection to every known directory server, using * connection purpose 'purpose' and uploading the payload 'payload' * (length 'payload_len'). The purpose should be one of * 'DIR_PURPOSE_UPLOAD_DIR' or 'DIR_PURPOSE_UPLOAD_RENDDESC'. */ void directory_post_to_dirservers(uint8_t purpose, const char *payload, size_t payload_len) { smartlist_t *dirservers; int post_via_tor; int post_to_hidserv_only; dirservers = router_get_trusted_dir_servers(); tor_assert(dirservers); /* Only old dirservers handle rendezvous descriptor publishing. */ post_to_hidserv_only = (purpose == DIR_PURPOSE_UPLOAD_RENDDESC); /* This tries dirservers which we believe to be down, but ultimately, that's * harmless, and we may as well err on the side of getting things uploaded. */ SMARTLIST_FOREACH(dirservers, trusted_dir_server_t *, ds, { routerstatus_t *rs = &(ds->fake_status.status); if (post_to_hidserv_only && !ds->is_hidserv_authority) continue; if (!post_to_hidserv_only && !(ds->is_v1_authority || ds->is_v2_authority)) continue; if (purpose == DIR_PURPOSE_UPLOAD_DIR) ds->has_accepted_serverdesc = 0; post_via_tor = purpose_is_private(purpose) || !fascist_firewall_allows_address_dir(ds->addr, ds->dir_port); directory_initiate_command_routerstatus(rs, purpose, post_via_tor, NULL, payload, payload_len); }); } /** Start a connection to a random running directory server, using * connection purpose 'purpose' and requesting 'resource'. * If retry_if_no_servers, then if all the possible servers seem * down, mark them up and try again. */ void directory_get_from_dirserver(uint8_t purpose, const char *resource, int retry_if_no_servers) { routerstatus_t *rs = NULL; or_options_t *options = get_options(); int prefer_authority = server_mode(options) && options->DirPort != 0; int directconn = !purpose_is_private(purpose); authority_type_t type; /* FFFF we could break this switch into its own function, and call * it elsewhere in directory.c. -RD */ switch (purpose) { case DIR_PURPOSE_FETCH_NETWORKSTATUS: case DIR_PURPOSE_FETCH_SERVERDESC: type = V2_AUTHORITY; break; case DIR_PURPOSE_FETCH_DIR: case DIR_PURPOSE_FETCH_RUNNING_LIST: type = V1_AUTHORITY; break; case DIR_PURPOSE_FETCH_RENDDESC: type = HIDSERV_AUTHORITY; break; default: log_warn(LD_BUG, "Unexpected purpose %d", (int)purpose); return; } if (!options->FetchServerDescriptors && type != HIDSERV_AUTHORITY) return; if (directconn) { if (prefer_authority) { /* only ask authdirservers, and don't ask myself */ rs = router_pick_trusteddirserver(type, 1, 1, retry_if_no_servers); } if (!rs) { /* anybody with a non-zero dirport will do */ rs = router_pick_directory_server(1, 1, type==V2_AUTHORITY, retry_if_no_servers); if (!rs) { const char *which; if (purpose == DIR_PURPOSE_FETCH_DIR) which = "directory"; else if (purpose == DIR_PURPOSE_FETCH_RUNNING_LIST) which = "status list"; else if (purpose == DIR_PURPOSE_FETCH_NETWORKSTATUS) which = "network status"; else // if (purpose == DIR_PURPOSE_FETCH_NETWORKSTATUS) which = "server descriptors"; log_info(LD_DIR, "No router found for %s; falling back to dirserver list", which); rs = router_pick_trusteddirserver(type, 1, 1, retry_if_no_servers); if (!rs) directconn = 0; /* last resort: try routing it via Tor */ } } } if (!directconn) { /* Never use fascistfirewall; we're going via Tor. */ if (purpose == DIR_PURPOSE_FETCH_RENDDESC) { /* only ask hidserv authorities, any of them will do */ rs = router_pick_trusteddirserver(HIDSERV_AUTHORITY, 0, 0, retry_if_no_servers); } else { /* anybody with a non-zero dirport will do. Disregard firewalls. */ rs = router_pick_directory_server(1, 0, type == V2_AUTHORITY, retry_if_no_servers); /* If we have any hope of building an indirect conn, we know some router * descriptors. If (rs==NULL), we can't build circuits anyway, so * there's no point in falling back to the authorities in this case. */ } } if (rs) directory_initiate_command_routerstatus(rs, purpose, !directconn, resource, NULL, 0); else { log_notice(LD_DIR, "While fetching directory info, " "no running dirservers known. Will try again later. " "(purpose %d)", purpose); if (!purpose_is_private(purpose)) { /* remember we tried them all and failed. */ directory_all_unreachable(time(NULL)); } } } /** Launch a new connection to the directory server router to upload or * download a service or rendezvous descriptor. purpose determines what * kind of directory connection we're launching, and must be one of * DIR_PURPOSE_{FETCH|UPLOAD}_{DIR|RENDDESC}. * * When uploading, payload and payload_len determine the content * of the HTTP post. Otherwise, payload should be NULL. * * When fetching a rendezvous descriptor, resource is the service ID we * want to fetch. */ void directory_initiate_command_router(routerinfo_t *router, uint8_t purpose, int private_connection, const char *resource, const char *payload, size_t payload_len) { directory_initiate_command(router->address, router->addr, router->dir_port, router->platform, router->cache_info.identity_digest, purpose, private_connection, resource, payload, payload_len); } /** Launch a new connection to the directory server status to upload or * download a server or rendezvous descriptor. purpose determines what * kind of directory connection we're launching, and must be one of * DIR_PURPOSE_{FETCH|UPLOAD}_{DIR|RENDDESC}. * * When uploading, payload and payload_len determine the content * of the HTTP post. Otherwise, payload should be NULL. * * When fetching a rendezvous descriptor, resource is the service ID we * want to fetch. */ void directory_initiate_command_routerstatus(routerstatus_t *status, uint8_t purpose, int private_connection, const char *resource, const char *payload, size_t payload_len) { const char *platform = NULL; routerinfo_t *router; char address_buf[INET_NTOA_BUF_LEN+1]; struct in_addr in; const char *address; if ((router = router_get_by_digest(status->identity_digest))) { platform = router->platform; address = router->address; } else { in.s_addr = htonl(status->addr); tor_inet_ntoa(&in, address_buf, sizeof(address_buf)); address = address_buf; } directory_initiate_command(address, status->addr, status->dir_port, platform, status->identity_digest, purpose, private_connection, resource, payload, payload_len); } /** Return true iff conn is the client side of a directory connection * we launched to ourself in order to determine the reachability of our * dir_port. */ static int directory_conn_is_self_reachability_test(dir_connection_t *conn) { if (conn->requested_resource && !strcmpstart(conn->requested_resource,"authority")) { routerinfo_t *me = router_get_my_routerinfo(); if (me && router_digest_is_me(conn->identity_digest) && me->addr == conn->_base.addr && me->dir_port == conn->_base.port) return 1; } return 0; } /** Called when we are unable to complete the client's request to a directory * server due to a network error: Mark the router as down and try again if * possible. */ void connection_dir_request_failed(dir_connection_t *conn) { if (router_digest_is_me(conn->identity_digest)) return; /* this was a test fetch. don't retry. */ router_set_status(conn->identity_digest, 0); /* don't try him again */ if (conn->_base.purpose == DIR_PURPOSE_FETCH_DIR || conn->_base.purpose == DIR_PURPOSE_FETCH_RUNNING_LIST) { log_info(LD_DIR, "Giving up on directory server at '%s:%d'; retrying", conn->_base.address, conn->_base.port); directory_get_from_dirserver(conn->_base.purpose, NULL, 0 /* don't retry_if_no_servers */); if (directory_conn_is_self_reachability_test(conn)) { routerinfo_t *me = router_get_my_routerinfo(); if (me) control_event_server_status(LOG_WARN, "REACHABILITY_FAILED DIRADDRESS=%s:%d", me->address, me->dir_port); } } else if (conn->_base.purpose == DIR_PURPOSE_FETCH_NETWORKSTATUS) { log_info(LD_DIR, "Giving up on directory server at '%s'; retrying", conn->_base.address); connection_dir_download_networkstatus_failed(conn, -1); } else if (conn->_base.purpose == DIR_PURPOSE_FETCH_SERVERDESC) { log_info(LD_DIR, "Giving up on directory server at '%s'; retrying", conn->_base.address); connection_dir_download_routerdesc_failed(conn); } } /** Called when an attempt to download one or more network status * documents on connection conn failed. Decide whether to * retry the fetch now, later, or never. */ static void connection_dir_download_networkstatus_failed(dir_connection_t *conn, int status_code) { if (!conn->requested_resource) { /* We never reached directory_send_command, which means that we never * opened a network connection. Either we're out of sockets, or the * network is down. Either way, retrying would be pointless. */ return; } if (!strcmpstart(conn->requested_resource, "all")) { /* We're a non-authoritative directory cache; try again. Ignore status * code, since we don't want to keep trying forever in a tight loop * if all the authorities are shutting us out. */ smartlist_t *trusted_dirs = router_get_trusted_dir_servers(); SMARTLIST_FOREACH(trusted_dirs, trusted_dir_server_t *, ds, ++ds->n_networkstatus_failures); directory_get_from_dirserver(conn->_base.purpose, "all.z", 0 /* don't retry_if_no_servers */); } else if (!strcmpstart(conn->requested_resource, "fp/")) { /* We were trying to download by fingerprint; mark them all as having * failed, and possibly retry them later.*/ smartlist_t *failed = smartlist_create(); dir_split_resource_into_fingerprints(conn->requested_resource+3, failed, NULL, 0, 0); if (smartlist_len(failed)) { dir_networkstatus_download_failed(failed, status_code); SMARTLIST_FOREACH(failed, char *, cp, tor_free(cp)); } smartlist_free(failed); } } /** Called when an attempt to download one or more router descriptors * on connection conn failed. */ static void connection_dir_download_routerdesc_failed(dir_connection_t *conn) { /* Try again. No need to increment the failure count for routerdescs, since * it's not their fault.*/ /* update_router_descriptor_downloads(time(NULL)); */ (void) conn; /* XXXX012 Why did the above get commented out? -NM */ } /** Return 1 if platform can handle a BEGIN_DIR cell, and if * we're willing to send one. Else return 0. */ /* XXX we should refactor directory.c to hand status->or_port around, * so we can check it here rather than platform. */ static int connection_dir_supports_tunnels(or_options_t *options, const char *platform) { return options->TunnelDirConns && platform && tor_version_as_new_as(platform, "0.1.2.2-alpha"); } /** Helper for directory_initiate_command_(router|trusted_dir): send the * command to a server whose address is address, whose IP is * addr, whose directory port is dir_port, whose tor version is * platform, and whose identity key digest is digest. The * platform argument is optional; the others are required. */ static void directory_initiate_command(const char *address, uint32_t addr, uint16_t dir_port, const char *platform, const char *digest, uint8_t purpose, int private_connection, const char *resource, const char *payload, size_t payload_len) { dir_connection_t *conn; or_options_t *options = get_options(); int want_to_tunnel = connection_dir_supports_tunnels(options, platform); tor_assert(address); tor_assert(addr); tor_assert(dir_port); tor_assert(digest); log_debug(LD_DIR, "private %d, want_to_tunnel %d.", private_connection, want_to_tunnel); switch (purpose) { case DIR_PURPOSE_FETCH_DIR: log_debug(LD_DIR,"initiating directory fetch"); break; case DIR_PURPOSE_FETCH_RENDDESC: log_debug(LD_DIR,"initiating hidden-service descriptor fetch"); break; case DIR_PURPOSE_UPLOAD_DIR: log_debug(LD_OR,"initiating server descriptor upload"); break; case DIR_PURPOSE_UPLOAD_RENDDESC: log_debug(LD_REND,"initiating hidden-service descriptor upload"); break; case DIR_PURPOSE_FETCH_RUNNING_LIST: log_debug(LD_DIR,"initiating running-routers fetch"); break; case DIR_PURPOSE_FETCH_NETWORKSTATUS: log_debug(LD_DIR,"initiating network-status fetch"); break; case DIR_PURPOSE_FETCH_SERVERDESC: log_debug(LD_DIR,"initiating server descriptor fetch"); break; default: log_err(LD_BUG, "Unrecognized directory connection purpose."); tor_assert(0); } conn = TO_DIR_CONN(connection_new(CONN_TYPE_DIR)); /* set up conn so it's got all the data we need to remember */ conn->_base.addr = addr; conn->_base.port = dir_port; conn->_base.address = tor_strdup(address); memcpy(conn->identity_digest, digest, DIGEST_LEN); conn->_base.purpose = purpose; /* give it an initial state */ conn->_base.state = DIR_CONN_STATE_CONNECTING; if (!private_connection && !want_to_tunnel) { /* then we want to connect directly */ conn->dirconn_direct = 1; if (options->HttpProxy) { addr = options->HttpProxyAddr; dir_port = options->HttpProxyPort; } switch (connection_connect(TO_CONN(conn), conn->_base.address, addr, dir_port)) { case -1: connection_dir_request_failed(conn); /* retry if we want */ connection_free(TO_CONN(conn)); return; case 1: /* start flushing conn */ conn->_base.state = DIR_CONN_STATE_CLIENT_SENDING; /* fall through */ case 0: /* queue the command on the outbuf */ directory_send_command(conn, platform, purpose, 1, resource, payload, payload_len); connection_watch_events(TO_CONN(conn), EV_READ | EV_WRITE); /* writable indicates finish, readable indicates broken link, error indicates broken link in windowsland. */ } } else { /* we want to connect via tor */ /* make an AP connection * populate it and add it at the right state * socketpair and hook up both sides */ conn->dirconn_direct = 0; conn->_base.s = connection_ap_make_bridge(conn->_base.address, conn->_base.port, digest, private_connection ? SOCKS_COMMAND_CONNECT : SOCKS_COMMAND_CONNECT_DIR); if (conn->_base.s < 0) { log_warn(LD_NET,"Making AP bridge to dirserver failed."); connection_mark_for_close(TO_CONN(conn)); return; } if (connection_add(TO_CONN(conn)) < 0) { log_warn(LD_NET,"Unable to add AP bridge to dirserver."); connection_mark_for_close(TO_CONN(conn)); return; } conn->_base.state = DIR_CONN_STATE_CLIENT_SENDING; /* queue the command on the outbuf */ directory_send_command(conn, platform, purpose, 0, resource, payload, payload_len); connection_watch_events(TO_CONN(conn), EV_READ | EV_WRITE); } } /** Queue an appropriate HTTP command on conn-\>outbuf. The other args * are as in directory_initiate_command. */ static void directory_send_command(dir_connection_t *conn, const char *platform, int purpose, int direct, const char *resource, const char *payload, size_t payload_len) { char proxystring[256]; char proxyauthstring[256]; char hoststring[128]; char *url; char request[8192]; const char *httpcommand = NULL; size_t len; tor_assert(conn); tor_assert(conn->_base.type == CONN_TYPE_DIR); tor_free(conn->requested_resource); if (resource) conn->requested_resource = tor_strdup(resource); /* come up with a string for which Host: we want */ if (conn->_base.port == 80) { strlcpy(hoststring, conn->_base.address, sizeof(hoststring)); } else { tor_snprintf(hoststring, sizeof(hoststring),"%s:%d", conn->_base.address, conn->_base.port); } /* come up with some proxy lines, if we're using one. */ if (direct && get_options()->HttpProxy) { char *base64_authenticator=NULL; const char *authenticator = get_options()->HttpProxyAuthenticator; tor_snprintf(proxystring, sizeof(proxystring),"http://%s", hoststring); if (authenticator) { base64_authenticator = alloc_http_authenticator(authenticator); if (!base64_authenticator) log_warn(LD_BUG, "Encoding http authenticator failed"); } if (base64_authenticator) { tor_snprintf(proxyauthstring, sizeof(proxyauthstring), "\r\nProxy-Authorization: Basic %s", base64_authenticator); tor_free(base64_authenticator); } else { proxyauthstring[0] = 0; } } else { proxystring[0] = 0; proxyauthstring[0] = 0; } switch (purpose) { case DIR_PURPOSE_FETCH_DIR: tor_assert(!resource); tor_assert(!payload); log_debug(LD_DIR, "Asking for compressed directory from server running %s", platform?escaped(platform):""); httpcommand = "GET"; url = tor_strdup("/tor/dir.z"); break; case DIR_PURPOSE_FETCH_RUNNING_LIST: tor_assert(!resource); tor_assert(!payload); httpcommand = "GET"; url = tor_strdup("/tor/running-routers"); break; case DIR_PURPOSE_FETCH_NETWORKSTATUS: httpcommand = "GET"; len = strlen(resource)+32; url = tor_malloc(len); tor_snprintf(url, len, "/tor/status/%s", resource); break; case DIR_PURPOSE_FETCH_SERVERDESC: httpcommand = "GET"; len = strlen(resource)+32; url = tor_malloc(len); tor_snprintf(url, len, "/tor/server/%s", resource); break; case DIR_PURPOSE_UPLOAD_DIR: tor_assert(!resource); tor_assert(payload); httpcommand = "POST"; url = tor_strdup("/tor/"); break; case DIR_PURPOSE_FETCH_RENDDESC: tor_assert(resource); tor_assert(!payload); /* this must be true or we wouldn't be doing the lookup */ tor_assert(strlen(resource) <= REND_SERVICE_ID_LEN); /* This breaks the function abstraction. */ strlcpy(conn->rend_query, resource, sizeof(conn->rend_query)); httpcommand = "GET"; /* Request the most recent versioned descriptor. */ // (XXXX We were going to switch this to fetch rendezvous1 descriptors, // but that never got testing, and it wasn't a good design.) len = strlen(resource)+32; url = tor_malloc(len); tor_snprintf(url, len, "/tor/rendezvous/%s", resource); break; case DIR_PURPOSE_UPLOAD_RENDDESC: tor_assert(!resource); tor_assert(payload); httpcommand = "POST"; url = tor_strdup("/tor/rendezvous/publish"); break; default: tor_assert(0); return; } if (strlen(proxystring) + strlen(url) >= 4096) { log_warn(LD_BUG, "Bug: squid does not like URLs longer than 4095 bytes, this " "one is %d bytes long: %s%s", (int)(strlen(proxystring) + strlen(url)), proxystring, url); } tor_snprintf(request, sizeof(request), "%s %s", httpcommand, proxystring); connection_write_to_buf(request, strlen(request), TO_CONN(conn)); connection_write_to_buf(url, strlen(url), TO_CONN(conn)); tor_free(url); if (!strcmp(httpcommand, "GET") && !payload) { tor_snprintf(request, sizeof(request), " HTTP/1.0\r\nHost: %s%s\r\n\r\n", hoststring, proxyauthstring); } else { tor_snprintf(request, sizeof(request), " HTTP/1.0\r\nContent-Length: %lu\r\nHost: %s%s\r\n\r\n", payload ? (unsigned long)payload_len : 0, hoststring, proxyauthstring); } connection_write_to_buf(request, strlen(request), TO_CONN(conn)); if (payload) { /* then send the payload afterwards too */ connection_write_to_buf(payload, payload_len, TO_CONN(conn)); } } /** Parse an HTTP request string headers of the form * \verbatim * "\%s [http[s]://]\%s HTTP/1..." * \endverbatim * If it's well-formed, strdup the second \%s into *url, and * nul-terminate it. If the url doesn't start with "/tor/", rewrite it * so it does. Return 0. * Otherwise, return -1. */ static int parse_http_url(char *headers, char **url) { char *s, *start, *tmp; s = (char *)eat_whitespace_no_nl(headers); if (!*s) return -1; s = (char *)find_whitespace(s); /* get past GET/POST */ if (!*s) return -1; s = (char *)eat_whitespace_no_nl(s); if (!*s) return -1; start = s; /* this is it, assuming it's valid */ s = (char *)find_whitespace(start); if (!*s) return -1; /* tolerate the http[s] proxy style of putting the hostname in the url */ if (s-start >= 4 && !strcmpstart(start,"http")) { tmp = start + 4; if (*tmp == 's') tmp++; if (s-tmp >= 3 && !strcmpstart(tmp,"://")) { tmp = strchr(tmp+3, '/'); if (tmp && tmp < s) { log_debug(LD_DIR,"Skipping over 'http[s]://hostname' string"); start = tmp; } } } if (s-start < 5 || strcmpstart(start,"/tor/")) { /* need to rewrite it */ *url = tor_malloc(s - start + 5); strlcpy(*url,"/tor", s-start+5); strlcat((*url)+4, start, s-start+1); } else { *url = tor_strndup(start, s-start); } return 0; } /** Return a copy of the first HTTP header in headers whose key is * which. The key should be given with a terminating colon and space; * this function copies everything after, up to but not including the * following \\r\\n. */ static char * http_get_header(const char *headers, const char *which) { const char *cp = headers; while (cp) { if (!strcmpstart(cp, which)) { char *eos; cp += strlen(which); if ((eos = strchr(cp,'\r'))) return tor_strndup(cp, eos-cp); else return tor_strdup(cp); } cp = strchr(cp, '\n'); if (cp) ++cp; } return NULL; } /** If headers indicates that a proxy was involved, then rewrite * conn-\>address to describe our best guess of the address that * originated this HTTP request. */ static void http_set_address_origin(const char *headers, connection_t *conn) { char *fwd; fwd = http_get_header(headers, "Forwarded-For: "); if (!fwd) fwd = http_get_header(headers, "X-Forwarded-For: "); if (fwd) { tor_free(conn->address); conn->address = tor_strdup(escaped(fwd)); tor_free(fwd); } } /** Parse an HTTP response string headers of the form * \verbatim * "HTTP/1.\%d \%d\%s\r\n...". * \endverbatim * * If it's well-formed, assign the status code to *code and * return 0. Otherwise, return -1. * * On success: If date is provided, set *date to the Date * header in the http headers, or 0 if no such header is found. If * compression is provided, set *compression to the * compression method given in the Content-Encoding header, or 0 if no * such header is found, or -1 if the value of the header is not * recognized. If reason is provided, strdup the reason string * into it. */ int parse_http_response(const char *headers, int *code, time_t *date, compress_method_t *compression, char **reason) { int n1, n2; char datestr[RFC1123_TIME_LEN+1]; smartlist_t *parsed_headers; tor_assert(headers); tor_assert(code); while (TOR_ISSPACE(*headers)) headers++; /* tolerate leading whitespace */ if (sscanf(headers, "HTTP/1.%d %d", &n1, &n2) < 2 || (n1 != 0 && n1 != 1) || (n2 < 100 || n2 >= 600)) { log_warn(LD_HTTP,"Failed to parse header %s",escaped(headers)); return -1; } *code = n2; parsed_headers = smartlist_create(); smartlist_split_string(parsed_headers, headers, "\n", SPLIT_SKIP_SPACE|SPLIT_IGNORE_BLANK, -1); if (reason) { smartlist_t *status_line_elements = smartlist_create(); tor_assert(smartlist_len(parsed_headers)); smartlist_split_string(status_line_elements, smartlist_get(parsed_headers, 0), " ", SPLIT_SKIP_SPACE|SPLIT_IGNORE_BLANK, 3); tor_assert(smartlist_len(status_line_elements) <= 3); if (smartlist_len(status_line_elements) == 3) { *reason = smartlist_get(status_line_elements, 2); smartlist_set(status_line_elements, 2, NULL); /* Prevent free */ } SMARTLIST_FOREACH(status_line_elements, char *, cp, tor_free(cp)); smartlist_free(status_line_elements); } if (date) { *date = 0; SMARTLIST_FOREACH(parsed_headers, const char *, s, if (!strcmpstart(s, "Date: ")) { strlcpy(datestr, s+6, sizeof(datestr)); /* This will do nothing on failure, so we don't need to check the result. We shouldn't warn, since there are many other valid date formats besides the one we use. */ parse_rfc1123_time(datestr, date); break; }); } if (compression) { const char *enc = NULL; SMARTLIST_FOREACH(parsed_headers, const char *, s, if (!strcmpstart(s, "Content-Encoding: ")) { enc = s+18; break; }); if (!enc || !strcmp(enc, "identity")) { *compression = NO_METHOD; } else if (!strcmp(enc, "deflate") || !strcmp(enc, "x-deflate")) { *compression = ZLIB_METHOD; } else if (!strcmp(enc, "gzip") || !strcmp(enc, "x-gzip")) { *compression = GZIP_METHOD; } else { log_info(LD_HTTP, "Unrecognized content encoding: %s. Trying to deal.", escaped(enc)); *compression = UNKNOWN_METHOD; } } SMARTLIST_FOREACH(parsed_headers, char *, s, tor_free(s)); smartlist_free(parsed_headers); return 0; } /** Return true iff body doesn't start with a plausible router or * running-list or directory opening. This is a sign of possible compression. **/ static int body_is_plausible(const char *body, size_t len, int purpose) { int i; if (len == 0) return 1; /* empty bodies don't need decompression */ if (len < 32) return 0; if (purpose != DIR_PURPOSE_FETCH_RENDDESC) { if (!strcmpstart(body,"router") || !strcmpstart(body,"signed-directory") || !strcmpstart(body,"network-status") || !strcmpstart(body,"running-routers")) return 1; for (i=0;i<32;++i) { if (!TOR_ISPRINT(body[i]) && !TOR_ISSPACE(body[i])) return 0; } return 1; } else { return 1; } } /** We are a client, and we've finished reading the server's * response. Parse and it and act appropriately. * * If we're still happy with using this directory server in the future, return * 0. Otherwise return -1; and the caller should consider trying the request * again. * * The caller will take care of marking the connection for close. */ static int connection_dir_client_reached_eof(dir_connection_t *conn) { char *body; char *headers; char *reason = NULL; size_t body_len=0, orig_len=0; int status_code; time_t date_header=0; int delta; compress_method_t compression; int plausible; int skewed=0; int allow_partial = conn->_base.purpose == DIR_PURPOSE_FETCH_SERVERDESC; int was_compressed=0; switch (fetch_from_buf_http(conn->_base.inbuf, &headers, MAX_HEADERS_SIZE, &body, &body_len, MAX_DIR_SIZE, allow_partial)) { case -1: /* overflow */ log_warn(LD_PROTOCOL, "'fetch' response too large (server '%s:%d'). Closing.", conn->_base.address, conn->_base.port); return -1; case 0: log_info(LD_HTTP, "'fetch' response not all here, but we're at eof. Closing."); return -1; /* case 1, fall through */ } orig_len = body_len; if (parse_http_response(headers, &status_code, &date_header, &compression, &reason) < 0) { log_warn(LD_HTTP,"Unparseable headers (server '%s:%d'). Closing.", conn->_base.address, conn->_base.port); tor_free(body); tor_free(headers); return -1; } if (!reason) reason = tor_strdup("[no reason given]"); log_debug(LD_DIR, "Received response from directory server '%s:%d': %d %s", conn->_base.address, conn->_base.port, status_code, escaped(reason)); /* now check if it's got any hints for us about our IP address. */ if (conn->dirconn_direct) { char *guess = http_get_header(headers, X_ADDRESS_HEADER); if (guess) { router_new_address_suggestion(guess); tor_free(guess); } } if (date_header > 0) { /* The date header was written very soon after we sent our request, * so compute the skew as the difference between sending the request * and the date header. (We used to check now-date_header, but that's * inaccurate if we spend a lot of time downloading.) */ delta = conn->_base.timestamp_lastwritten - date_header; if (abs(delta)>ALLOW_DIRECTORY_TIME_SKEW) { int trusted = router_digest_is_trusted_dir(conn->identity_digest); log_fn(trusted ? LOG_WARN : LOG_INFO, LD_HTTP, "Received directory with skewed time (server '%s:%d'): " "we are %d minutes %s, or the directory is %d minutes %s.", conn->_base.address, conn->_base.port, abs(delta)/60, delta>0 ? "ahead" : "behind", abs(delta)/60, delta>0 ? "behind" : "ahead"); skewed = 1; /* don't check the recommended-versions line */ control_event_general_status(trusted ? LOG_WARN : LOG_NOTICE, "CLOCK_SKEW SKEW=%d SOURCE=DIRSERV:%s:%d", delta, conn->_base.address, conn->_base.port); } else { log_debug(LD_HTTP, "Time on received directory is within tolerance; " "we are %d seconds skewed. (That's okay.)", delta); } } (void) skewed; /* skewed isn't used yet. */ if (status_code == 503) { local_routerstatus_t *rs; trusted_dir_server_t *ds; time_t now = time(NULL); log_info(LD_DIR,"Received http status code %d (%s) from server " "'%s:%d'. I'll try again soon.", status_code, escaped(reason), conn->_base.address, conn->_base.port); if ((rs = router_get_combined_status_by_digest(conn->identity_digest))) rs->last_dir_503_at = now; if ((ds = router_get_trusteddirserver_by_digest(conn->identity_digest))) ds->fake_status.last_dir_503_at = now; tor_free(body); tor_free(headers); tor_free(reason); return -1; } plausible = body_is_plausible(body, body_len, conn->_base.purpose); if (compression != NO_METHOD || !plausible) { char *new_body = NULL; size_t new_len = 0; compress_method_t guessed = detect_compression_method(body, body_len); if (compression == UNKNOWN_METHOD || guessed != compression) { /* Tell the user if we don't believe what we're told about compression.*/ const char *description1, *description2; if (compression == ZLIB_METHOD) description1 = "as deflated"; else if (compression == GZIP_METHOD) description1 = "as gzipped"; else if (compression == NO_METHOD) description1 = "as uncompressed"; else description1 = "with an unknown Content-Encoding"; if (guessed == ZLIB_METHOD) description2 = "deflated"; else if (guessed == GZIP_METHOD) description2 = "gzipped"; else if (!plausible) description2 = "confusing binary junk"; else description2 = "uncompressed"; log_info(LD_HTTP, "HTTP body from server '%s:%d' was labeled %s, " "but it seems to be %s.%s", conn->_base.address, conn->_base.port, description1, description2, (compression>0 && guessed>0)?" Trying both.":""); } /* Try declared compression first if we can. */ if (compression == GZIP_METHOD || compression == ZLIB_METHOD) tor_gzip_uncompress(&new_body, &new_len, body, body_len, compression, !allow_partial, LOG_PROTOCOL_WARN); /* Okay, if that didn't work, and we think that it was compressed * differently, try that. */ if (!new_body && (guessed == GZIP_METHOD || guessed == ZLIB_METHOD) && compression != guessed) tor_gzip_uncompress(&new_body, &new_len, body, body_len, guessed, !allow_partial, LOG_PROTOCOL_WARN); /* If we're pretty sure that we have a compressed directory, and * we didn't manage to uncompress it, then warn and bail. */ if (!plausible && !new_body) { log_fn(LOG_PROTOCOL_WARN, LD_HTTP, "Unable to decompress HTTP body (server '%s:%d').", conn->_base.address, conn->_base.port); tor_free(body); tor_free(headers); tor_free(reason); return -1; } if (new_body) { tor_free(body); body = new_body; body_len = new_len; was_compressed = 1; } } if (conn->_base.purpose == DIR_PURPOSE_FETCH_DIR) { /* fetch/process the directory to cache it. */ log_info(LD_DIR,"Received directory (size %d) from server '%s:%d'", (int)body_len, conn->_base.address, conn->_base.port); if (status_code != 200) { log_warn(LD_DIR,"Received http status code %d (%s) from server " "'%s:%d' while fetching directory. I'll try again soon.", status_code, escaped(reason), conn->_base.address, conn->_base.port); tor_free(body); tor_free(headers); tor_free(reason); return -1; } if (router_parse_directory(body) < 0) { log_notice(LD_DIR,"I failed to parse the directory I fetched from " "'%s:%d'. Ignoring.", conn->_base.address, conn->_base.port); } note_request(was_compressed?"dl/dir.z":"dl/dir", orig_len); } if (conn->_base.purpose == DIR_PURPOSE_FETCH_RUNNING_LIST) { /* just update our list of running routers, if this list is new info */ log_info(LD_DIR,"Received running-routers list (size %d)", (int)body_len); if (status_code != 200) { log_warn(LD_DIR,"Received http status code %d (%s) from server " "'%s:%d' while fetching running-routers. I'll try again soon.", status_code, escaped(reason), conn->_base.address, conn->_base.port); tor_free(body); tor_free(headers); tor_free(reason); return -1; } if (router_parse_runningrouters(body)<0) { log_warn(LD_DIR, "Bad running-routers from server '%s:%d'. I'll try again soon.", conn->_base.address, conn->_base.port); tor_free(body); tor_free(headers); tor_free(reason); return -1; } note_request(was_compressed?"dl/running-routers.z": "dl/running-routers", orig_len); } if (conn->_base.purpose == DIR_PURPOSE_FETCH_NETWORKSTATUS) { smartlist_t *which = NULL; networkstatus_source_t source; char *cp; log_info(LD_DIR,"Received networkstatus objects (size %d) from server " "'%s:%d'",(int) body_len, conn->_base.address, conn->_base.port); if (status_code != 200) { log_warn(LD_DIR, "Received http status code %d (%s) from server " "'%s:%d' while fetching \"/tor/status/%s\". I'll try again soon.", status_code, escaped(reason), conn->_base.address, conn->_base.port, conn->requested_resource); tor_free(body); tor_free(headers); tor_free(reason); connection_dir_download_networkstatus_failed(conn, status_code); return -1; } note_request(was_compressed?"dl/status.z":"dl/status", orig_len); if (conn->requested_resource && !strcmpstart(conn->requested_resource,"fp/")) { source = NS_FROM_DIR_BY_FP; which = smartlist_create(); dir_split_resource_into_fingerprints(conn->requested_resource+3, which, NULL, 0, 0); } else if (conn->requested_resource && !strcmpstart(conn->requested_resource, "all")) { source = NS_FROM_DIR_ALL; which = smartlist_create(); SMARTLIST_FOREACH(router_get_trusted_dir_servers(), trusted_dir_server_t *, ds, { char *cp = tor_malloc(HEX_DIGEST_LEN+1); base16_encode(cp, HEX_DIGEST_LEN+1, ds->digest, DIGEST_LEN); smartlist_add(which, cp); }); } else { /* Can we even end up here? -- weasel*/ source = NS_FROM_DIR_BY_FP; log_warn(LD_BUG, "We received a networkstatus but we didn't ask " "for it by fp, nor did we ask for all."); } cp = body; while (*cp) { char *next = strstr(cp, "\nnetwork-status-version"); if (next) next[1] = '\0'; /* learn from it, and then remove it from 'which' */ if (router_set_networkstatus(cp, time(NULL), source, which)<0) break; if (next) { next[1] = 'n'; cp = next+1; } else break; } routers_update_all_from_networkstatus(); /*launches router downloads*/ directory_info_has_arrived(time(NULL), 0); if (which) { if (smartlist_len(which)) { dir_networkstatus_download_failed(which, status_code); } SMARTLIST_FOREACH(which, char *, cp, tor_free(cp)); smartlist_free(which); } } if (conn->_base.purpose == DIR_PURPOSE_FETCH_SERVERDESC) { smartlist_t *which = NULL; int n_asked_for = 0; log_info(LD_DIR,"Received server info (size %d) from server '%s:%d'", (int)body_len, conn->_base.address, conn->_base.port); note_request(was_compressed?"dl/server.z":"dl/server", orig_len); if (conn->requested_resource && !strcmpstart(conn->requested_resource,"d/")) { which = smartlist_create(); dir_split_resource_into_fingerprints(conn->requested_resource+2, which, NULL, 0, 0); n_asked_for = smartlist_len(which); } if (status_code != 200) { int dir_okay = status_code == 404 || (status_code == 400 && !strcmp(reason, "Servers unavailable.")); /* 404 means that it didn't have them; no big deal. * Older (pre-0.1.1.8) servers said 400 Servers unavailable instead. */ log_fn(dir_okay ? LOG_INFO : LOG_WARN, LD_DIR, "Received http status code %d (%s) from server '%s:%d' " "while fetching \"/tor/server/%s\". I'll try again soon.", status_code, escaped(reason), conn->_base.address, conn->_base.port, conn->requested_resource); if (!which) { connection_dir_download_routerdesc_failed(conn); } else { dir_routerdesc_download_failed(which, status_code); SMARTLIST_FOREACH(which, char *, cp, tor_free(cp)); smartlist_free(which); } tor_free(body); tor_free(headers); tor_free(reason); return dir_okay ? 0 : -1; } /* Learn the routers, assuming we requested by fingerprint or "all". * Right now, we only use "authority" to fetch ourself, so we don't want * to risk replacing ourself with a router running at the addr:port we * think we have. */ if (which || (conn->requested_resource && !strcmpstart(conn->requested_resource, "all"))) { /* as we learn from them, we remove them from 'which' */ router_load_routers_from_string(body, SAVED_NOWHERE, which); directory_info_has_arrived(time(NULL), 0); } if (which) { /* mark remaining ones as failed */ log_info(LD_DIR, "Received %d/%d routers requested from %s:%d", n_asked_for-smartlist_len(which), n_asked_for, conn->_base.address, (int)conn->_base.port); if (smartlist_len(which)) { dir_routerdesc_download_failed(which, status_code); } SMARTLIST_FOREACH(which, char *, cp, tor_free(cp)); smartlist_free(which); } if (directory_conn_is_self_reachability_test(conn)) router_dirport_found_reachable(); } if (conn->_base.purpose == DIR_PURPOSE_UPLOAD_DIR) { switch (status_code) { case 200: { int all_done = 1; trusted_dir_server_t *ds = router_get_trusteddirserver_by_digest(conn->identity_digest); smartlist_t *servers; log_info(LD_GENERAL,"eof (status 200) after uploading server " "descriptor: finished."); control_event_server_status( LOG_NOTICE, "ACCEPTED_SERVER_DESCRIPTOR DIRAUTH=%s:%d", conn->_base.address, conn->_base.port); ds->has_accepted_serverdesc = 1; servers = router_get_trusted_dir_servers(); SMARTLIST_FOREACH(servers, trusted_dir_server_t *, d, { if ((d->is_v1_authority || d->is_v2_authority) && !d->has_accepted_serverdesc) { all_done = 0; break; } }); if (all_done) control_event_server_status(LOG_NOTICE, "GOOD_SERVER_DESCRIPTOR"); } break; case 400: log_warn(LD_GENERAL,"http status 400 (%s) response from " "dirserver '%s:%d'. Please correct.", escaped(reason), conn->_base.address, conn->_base.port); control_event_server_status(LOG_WARN, "BAD_SERVER_DESCRIPTOR DIRAUTH=%s:%d REASON=\"%s\"", conn->_base.address, conn->_base.port, escaped(reason)); break; case 403: log_warn(LD_GENERAL, "http status 403 (%s) response from dirserver " "'%s:%d'. Is your clock skewed? Have you mailed us your key " "fingerprint? Are you using the right key? Are you using a " "private IP address? See http://tor.eff.org/doc/" "tor-doc-server.html",escaped(reason), conn->_base.address, conn->_base.port); control_event_server_status(LOG_WARN, "BAD_SERVER_DESCRIPTOR DIRAUTH=%s:%d REASON=\"%s\"", conn->_base.address, conn->_base.port, escaped(reason)); break; default: log_warn(LD_GENERAL, "http status %d (%s) reason unexpected while uploading " "descriptor to server '%s:%d').", status_code, escaped(reason), conn->_base.address, conn->_base.port); break; } /* return 0 in all cases, since we don't want to mark any * dirservers down just because they don't like us. */ } if (conn->_base.purpose == DIR_PURPOSE_FETCH_RENDDESC) { log_info(LD_REND,"Received rendezvous descriptor (size %d, status %d " "(%s))", (int)body_len, status_code, escaped(reason)); switch (status_code) { case 200: if (rend_cache_store(body, body_len) < 0) { log_warn(LD_REND,"Failed to store rendezvous descriptor."); /* alice's ap_stream will notice when connection_mark_for_close * cleans it up */ } else { /* success. notify pending connections about this. */ conn->_base.purpose = DIR_PURPOSE_HAS_FETCHED_RENDDESC; rend_client_desc_here(conn->rend_query); } break; case 404: /* not there. pending connections will be notified when * connection_mark_for_close cleans it up. */ break; case 400: log_warn(LD_REND, "http status 400 (%s). Dirserver didn't like our " "rendezvous query?", escaped(reason)); break; default: log_warn(LD_REND,"http status %d (%s) response unexpected while " "fetching hidden service descriptor (server '%s:%d').", status_code, escaped(reason), conn->_base.address, conn->_base.port); break; } } if (conn->_base.purpose == DIR_PURPOSE_UPLOAD_RENDDESC) { switch (status_code) { case 200: log_info(LD_REND, "Uploading rendezvous descriptor: finished with status " "200 (%s)", escaped(reason)); break; case 400: log_warn(LD_REND,"http status 400 (%s) response from dirserver " "'%s:%d'. Malformed rendezvous descriptor?", escaped(reason), conn->_base.address, conn->_base.port); break; default: log_warn(LD_REND,"http status %d (%s) response unexpected (server " "'%s:%d').", status_code, escaped(reason), conn->_base.address, conn->_base.port); break; } } tor_free(body); tor_free(headers); tor_free(reason); return 0; } /** Called when a directory connection reaches EOF */ int connection_dir_reached_eof(dir_connection_t *conn) { int retval; if (conn->_base.state != DIR_CONN_STATE_CLIENT_READING) { log_info(LD_HTTP,"conn reached eof, not reading. Closing."); connection_close_immediate(TO_CONN(conn)); /* error: give up on flushing */ connection_mark_for_close(TO_CONN(conn)); return -1; } retval = connection_dir_client_reached_eof(conn); if (retval == 0) /* success */ conn->_base.state = DIR_CONN_STATE_CLIENT_FINISHED; connection_mark_for_close(TO_CONN(conn)); return retval; } /** If any directory object is arriving, and it's over 10MB large, we're * getting DoS'd. (As of 0.1.2.x, raw directories are about 1MB, and we never * ask for more than 96 router descriptors at a time.) */ #define MAX_DIRECTORY_OBJECT_SIZE (10*(1<<20)) /** Read handler for directory connections. (That's connections to * directory servers and connections at directory servers.) */ int connection_dir_process_inbuf(dir_connection_t *conn) { tor_assert(conn); tor_assert(conn->_base.type == CONN_TYPE_DIR); /* Directory clients write, then read data until they receive EOF; * directory servers read data until they get an HTTP command, then * write their response (when it's finished flushing, they mark for * close). */ /* If we're on the dirserver side, look for a command. */ if (conn->_base.state == DIR_CONN_STATE_SERVER_COMMAND_WAIT) { if (directory_handle_command(conn) < 0) { connection_mark_for_close(TO_CONN(conn)); return -1; } return 0; } if (buf_datalen(conn->_base.inbuf) > MAX_DIRECTORY_OBJECT_SIZE) { log_warn(LD_HTTP, "Too much data received from directory connection: " "denial of service attempt, or you need to upgrade?"); connection_mark_for_close(TO_CONN(conn)); return -1; } if (!conn->_base.inbuf_reached_eof) log_debug(LD_HTTP,"Got data, not eof. Leaving on inbuf."); return 0; } /** Create an http response for the client conn out of * status and reason_phrase. Write it to conn. */ static void write_http_status_line(dir_connection_t *conn, int status, const char *reason_phrase) { char buf[256]; if (tor_snprintf(buf, sizeof(buf), "HTTP/1.0 %d %s\r\n\r\n", status, reason_phrase) < 0) { log_warn(LD_BUG,"Bug: status line too long."); return; } connection_write_to_buf(buf, strlen(buf), TO_CONN(conn)); } /** Write the header for an HTTP/1.0 response onto conn-\>outbuf, * with type as the Content-Type. * * If length is nonnegative, it is the Content-Length. * If encoding is provided, it is the Content-Encoding. * If cache_lifetime is greater than 0, the content may be cached for * up to cache_lifetime seconds. Otherwise, the content may not be cached. */ static void write_http_response_header(dir_connection_t *conn, ssize_t length, const char *type, const char *encoding, int cache_lifetime) { char date[RFC1123_TIME_LEN+1]; char tmp[1024]; char *cp; time_t now = time(NULL); tor_assert(conn); tor_assert(type); format_rfc1123_time(date, now); cp = tmp; tor_snprintf(cp, sizeof(tmp), "HTTP/1.0 200 OK\r\nDate: %s\r\nContent-Type: %s\r\n", date, type); cp += strlen(tmp); if (!is_internal_IP(conn->_base.addr, 0)) { /* Don't report the source address for a localhost/private connection. */ tor_snprintf(cp, sizeof(tmp)-(cp-tmp), X_ADDRESS_HEADER "%s\r\n", conn->_base.address); cp += strlen(cp); } if (encoding) { tor_snprintf(cp, sizeof(tmp)-(cp-tmp), "Content-Encoding: %s\r\n", encoding); cp += strlen(cp); } if (length >= 0) { tor_snprintf(cp, sizeof(tmp)-(cp-tmp), "Content-Length: %ld\r\n", (long)length); cp += strlen(cp); } if (cache_lifetime > 0) { char expbuf[RFC1123_TIME_LEN+1]; format_rfc1123_time(expbuf, now + cache_lifetime); /* We could say 'Cache-control: max-age=%d' here if we start doing * http/1.1 */ tor_snprintf(cp, sizeof(tmp)-(cp-tmp), "Expires: %s\r\n", expbuf); cp += strlen(cp); } else { /* We could say 'Cache-control: no-cache' here if we start doing * http/1.1 */ strlcpy(cp, "Pragma: no-cache\r\n", sizeof(tmp)-(cp-tmp)); cp += strlen(cp); } if (sizeof(tmp)-(cp-tmp) > 3) memcpy(cp, "\r\n", 3); else tor_assert(0); connection_write_to_buf(tmp, strlen(tmp), TO_CONN(conn)); } /** Helper function: return 1 if there are any dir conns of purpose * purpose that are going elsewhere than our own ORPort/Dirport. * Else return 0. */ static int already_fetching_directory(int purpose) { int i, n; connection_t *conn; connection_t **carray; get_connection_array(&carray,&n); for (i=0;itype == CONN_TYPE_DIR && conn->purpose == purpose && !conn->marked_for_close && !router_digest_is_me(TO_DIR_CONN(conn)->identity_digest)) return 1; } return 0; } #undef INSTRUMENT_DOWNLOADS #ifdef INSTRUMENT_DOWNLOADS /** DOCDOC */ static strmap_t *request_bytes_map = NULL; /** DOCDOC */ static void note_request(const char *key, size_t bytes) { uint64_t *n; if (!request_bytes_map) request_bytes_map = strmap_new(); n = strmap_get(request_bytes_map, key); if (!n) { n = tor_malloc_zero(sizeof(uint64_t)); strmap_set(request_bytes_map, key, n); } *n += bytes; } /** DOCDOC */ char * directory_dump_request_log(void) { smartlist_t *lines; char tmp[256]; char *result; strmap_iter_t *iter; if (!request_bytes_map) request_bytes_map = strmap_new(); lines = smartlist_create(); for (iter = strmap_iter_init(request_bytes_map); !strmap_iter_done(iter); iter = strmap_iter_next(request_bytes_map, iter)) { const char *key; void *val; uint64_t *n; strmap_iter_get(iter, &key, &val); n = val; tor_snprintf(tmp, sizeof(tmp), "%s "U64_FORMAT"\n", key, U64_PRINTF_ARG(*n)); smartlist_add(lines, tor_strdup(tmp)); } smartlist_sort_strings(lines); result = smartlist_join_strings(lines, "", 0, NULL); SMARTLIST_FOREACH(lines, char *, cp, tor_free(cp)); smartlist_free(lines); return result; } #else static void note_request(const char *key, size_t bytes) { (void)key; (void)bytes; } char * directory_dump_request_log(void) { return tor_strdup("Not supported."); } #endif /** Helper function: called when a dirserver gets a complete HTTP GET * request. Look for a request for a directory or for a rendezvous * service descriptor. On finding one, write a response into * conn-\>outbuf. If the request is unrecognized, send a 400. * Always return 0. */ static int directory_handle_command_get(dir_connection_t *conn, char *headers, char *body, size_t body_len) { size_t dlen; const char *cp; char *url = NULL; or_options_t *options = get_options(); /* We ignore the body of a GET request. */ (void)body; (void)body_len; log_debug(LD_DIRSERV,"Received GET command."); conn->_base.state = DIR_CONN_STATE_SERVER_WRITING; if (parse_http_url(headers, &url) < 0) { write_http_status_line(conn, 400, "Bad request"); return 0; } log_debug(LD_DIRSERV,"rewritten url as '%s'.", url); if (!strcmp(url,"/tor/") || !strcmp(url,"/tor/dir.z")) { /* dir fetch */ int deflated = !strcmp(url,"/tor/dir.z"); cached_dir_t *d = dirserv_get_directory(); if (!d) { log_notice(LD_DIRSERV,"Client asked for the mirrored directory, but we " "don't have a good one yet. Sending 503 Dir not available."); write_http_status_line(conn, 503, "Directory unavailable"); /* try to get a new one now */ if (!already_fetching_directory(DIR_PURPOSE_FETCH_DIR)) directory_get_from_dirserver(DIR_PURPOSE_FETCH_DIR, NULL, 1); tor_free(url); return 0; } dlen = deflated ? d->dir_z_len : d->dir_len; if (global_write_bucket_low(TO_CONN(conn), dlen, 1)) { log_info(LD_DIRSERV, "Client asked for the mirrored directory, but we've been " "writing too many bytes lately. Sending 503 Dir busy."); write_http_status_line(conn, 503, "Directory busy, try again later"); tor_free(url); return 0; } note_request(url, dlen); tor_free(url); log_debug(LD_DIRSERV,"Dumping %sdirectory to client.", deflated?"deflated ":""); write_http_response_header(conn, dlen, deflated?"application/octet-stream":"text/plain", deflated?"deflate":"identity", FULL_DIR_CACHE_LIFETIME); conn->cached_dir = d; conn->cached_dir_offset = 0; if (! deflated) conn->zlib_state = tor_zlib_new(0, ZLIB_METHOD); ++d->refcnt; /* Prime the connection with some data. */ conn->dir_spool_src = DIR_SPOOL_CACHED_DIR; connection_dirserv_flushed_some(conn); return 0; } if (!strcmp(url,"/tor/running-routers") || !strcmp(url,"/tor/running-routers.z")) { /* running-routers fetch */ int deflated = !strcmp(url,"/tor/running-routers.z"); dlen = dirserv_get_runningrouters(&cp, deflated); if (!dlen) { /* we failed to create/cache cp */ write_http_status_line(conn, 503, "Directory unavailable"); /* try to get a new one now */ if (!already_fetching_directory(DIR_PURPOSE_FETCH_RUNNING_LIST)) directory_get_from_dirserver(DIR_PURPOSE_FETCH_RUNNING_LIST, NULL, 1); tor_free(url); return 0; } if (global_write_bucket_low(TO_CONN(conn), dlen, 1)) { log_info(LD_DIRSERV, "Client asked for running-routers, but we've been " "writing too many bytes lately. Sending 503 Dir busy."); write_http_status_line(conn, 503, "Directory busy, try again later"); tor_free(url); return 0; } note_request(url, dlen); tor_free(url); write_http_response_header(conn, dlen, deflated?"application/octet-stream":"text/plain", deflated?"deflate":"identity", RUNNINGROUTERS_CACHE_LIFETIME); connection_write_to_buf(cp, strlen(cp), TO_CONN(conn)); return 0; } if (!strcmpstart(url,"/tor/status/")) { /* v2 network status fetch. */ size_t url_len = strlen(url); int deflated = !strcmp(url+url_len-2, ".z"); smartlist_t *dir_fps = smartlist_create(); const char *request_type = NULL; const char *key = url + strlen("/tor/status/"); if (deflated) url[url_len-2] = '\0'; dirserv_get_networkstatus_v2_fingerprints(dir_fps, key); if (!strcmpstart(key, "fp/")) request_type = deflated?"/tor/status/fp.z":"/tor/status/fp"; else if (!strcmpstart(key, "authority")) request_type = deflated?"/tor/status/authority.z": "/tor/status/authority"; else if (!strcmpstart(key, "all")) request_type = deflated?"/tor/status/all.z":"/tor/status/all"; else request_type = "/tor/status/?"; tor_free(url); if (!smartlist_len(dir_fps)) { /* we failed to create/cache cp */ write_http_status_line(conn, 503, "Network status object unavailable"); smartlist_free(dir_fps); return 0; } dlen = dirserv_estimate_data_size(dir_fps, 0, deflated); if (global_write_bucket_low(TO_CONN(conn), dlen, 2)) { log_info(LD_DIRSERV, "Client asked for network status lists, but we've been " "writing too many bytes lately. Sending 503 Dir busy."); write_http_status_line(conn, 503, "Directory busy, try again later"); SMARTLIST_FOREACH(dir_fps, char *, cp, tor_free(cp)); smartlist_free(dir_fps); return 0; } // note_request(request_type,dlen); (void) request_type; write_http_response_header(conn, -1, deflated?"application/octet_stream":"text/plain", deflated?"deflate":NULL, smartlist_len(dir_fps) == 1 ? NETWORKSTATUS_CACHE_LIFETIME:0); conn->fingerprint_stack = dir_fps; if (! deflated) conn->zlib_state = tor_zlib_new(0, ZLIB_METHOD); /* Prime the connection with some data. */ conn->dir_spool_src = DIR_SPOOL_NETWORKSTATUS; connection_dirserv_flushed_some(conn); return 0; } if (!strcmpstart(url,"/tor/server/")) { size_t url_len = strlen(url); int deflated = !strcmp(url+url_len-2, ".z"); int res; const char *msg; const char *request_type = NULL; int cache_lifetime = 0; if (deflated) url[url_len-2] = '\0'; conn->fingerprint_stack = smartlist_create(); res = dirserv_get_routerdesc_fingerprints(conn->fingerprint_stack, url, &msg); if (!strcmpstart(url, "/tor/server/fp/")) { request_type = deflated?"/tor/server/fp.z":"/tor/server/fp"; if (smartlist_len(conn->fingerprint_stack) == 1) cache_lifetime = ROUTERDESC_CACHE_LIFETIME; } else if (!strcmpstart(url, "/tor/server/authority")) { request_type = deflated?"/tor/server/authority.z": "/tor/server/authority"; cache_lifetime = ROUTERDESC_CACHE_LIFETIME; } else if (!strcmpstart(url, "/tor/server/all")) { request_type = deflated?"/tor/server/all.z":"/tor/server/all"; cache_lifetime = FULL_DIR_CACHE_LIFETIME; } else if (!strcmpstart(url, "/tor/server/d/")) { request_type = deflated?"/tor/server/d.z":"/tor/server/d"; if (smartlist_len(conn->fingerprint_stack) == 1) cache_lifetime = ROUTERDESC_BY_DIGEST_CACHE_LIFETIME; } else { request_type = "/tor/server/?"; } (void) request_type; /* usable for note_request. */ if (!strcmpstart(url, "/tor/server/d/")) conn->dir_spool_src = DIR_SPOOL_SERVER_BY_DIGEST; else conn->dir_spool_src = DIR_SPOOL_SERVER_BY_FP; tor_free(url); if (res < 0) write_http_status_line(conn, 404, msg); else { dlen = dirserv_estimate_data_size(conn->fingerprint_stack, 1, deflated); if (global_write_bucket_low(TO_CONN(conn), dlen, 2)) { log_info(LD_DIRSERV, "Client asked for server descriptors, but we've been " "writing too many bytes lately. Sending 503 Dir busy."); write_http_status_line(conn, 503, "Directory busy, try again later"); return 0; } write_http_response_header(conn, -1, deflated?"application/octet_stream":"text/plain", deflated?"deflate":NULL, cache_lifetime); if (deflated) conn->zlib_state = tor_zlib_new(1, ZLIB_METHOD); /* Prime the connection with some data. */ connection_dirserv_flushed_some(conn); } return 0; } if (options->HSAuthoritativeDir && (!strcmpstart(url,"/tor/rendezvous/") || !strcmpstart(url,"/tor/rendezvous1/"))) { /* rendezvous descriptor fetch */ const char *descp; size_t desc_len; int versioned = !strcmpstart(url,"/tor/rendezvous1/"); const char *query = url+strlen("/tor/rendezvous/")+(versioned?1:0); switch (rend_cache_lookup_desc(query, versioned?-1:0, &descp, &desc_len)) { case 1: /* valid */ write_http_response_header(conn, desc_len, "application/octet-stream", NULL, 0); note_request("/tor/rendezvous?/", desc_len); /* need to send descp separately, because it may include nuls */ connection_write_to_buf(descp, desc_len, TO_CONN(conn)); break; case 0: /* well-formed but not present */ write_http_status_line(conn, 404, "Not found"); break; case -1: /* not well-formed */ write_http_status_line(conn, 400, "Bad request"); break; } tor_free(url); return 0; } if (!strcmpstart(url,"/tor/bytes.txt")) { char *bytes = directory_dump_request_log(); size_t len = strlen(bytes); write_http_response_header(conn, len, "text/plain", NULL, 0); connection_write_to_buf(bytes, len, TO_CONN(conn)); tor_free(bytes); tor_free(url); return 0; } if (!strcmp(url,"/tor/robots.txt")) { /* /robots.txt will have been rewritten to /tor/robots.txt */ char robots[] = "User-agent: *\r\nDisallow: /\r\n"; size_t len = strlen(robots); write_http_response_header(conn, len, "text/plain", NULL, ROBOTS_CACHE_LIFETIME); connection_write_to_buf(robots, len, TO_CONN(conn)); tor_free(url); return 0; } if (!strcmp(url,"/tor/dir-all-weaselhack") && (conn->_base.addr == 0x7f000001ul) && authdir_mode(options)) { /* XXX until weasel rewrites his scripts XXXX012 */ char *new_directory=NULL; if (dirserv_dump_directory_to_string(&new_directory, get_identity_key(), 1)) { log_warn(LD_BUG, "Error creating full v1 directory."); tor_free(new_directory); write_http_status_line(conn, 503, "Directory unavailable"); return 0; } dlen = strlen(new_directory); write_http_response_header(conn, dlen, "text/plain", "identity", 0); connection_write_to_buf(new_directory, dlen, TO_CONN(conn)); tor_free(new_directory); tor_free(url); return 0; } /* we didn't recognize the url */ write_http_status_line(conn, 404, "Not found"); tor_free(url); return 0; } /** Helper function: called when a dirserver gets a complete HTTP POST * request. Look for an uploaded server descriptor or rendezvous * service descriptor. On finding one, process it and write a * response into conn-\>outbuf. If the request is unrecognized, send a * 400. Always return 0. */ static int directory_handle_command_post(dir_connection_t *conn, char *headers, char *body, size_t body_len) { char *url = NULL; or_options_t *options = get_options(); log_debug(LD_DIRSERV,"Received POST command."); conn->_base.state = DIR_CONN_STATE_SERVER_WRITING; if (!authdir_mode(options)) { /* we just provide cached directories; we don't want to * receive anything. */ write_http_status_line(conn, 400, "Nonauthoritative directory does not " "accept posted server descriptors"); return 0; } if (parse_http_url(headers, &url) < 0) { write_http_status_line(conn, 400, "Bad request"); return 0; } log_debug(LD_DIRSERV,"rewritten url as '%s'.", url); if (!strcmp(url,"/tor/")) { /* server descriptor post */ const char *msg; int r = dirserv_add_descriptor(body, &msg); tor_assert(msg); if (r > 0) dirserv_get_directory(); /* rebuild and write to disk */ switch (r) { case -2: case -1: case 1: log_notice(LD_DIRSERV,"Rejected router descriptor from %s.", conn->_base.address); /* malformed descriptor, or something wrong */ write_http_status_line(conn, 400, msg); break; case 0: /* accepted but discarded */ case 2: /* accepted */ write_http_status_line(conn, 200, msg); break; } goto done; } if (options->HSAuthoritativeDir && !strcmpstart(url,"/tor/rendezvous/publish")) { /* rendezvous descriptor post */ if (rend_cache_store(body, body_len) < 0) { // char tmp[1024*2+1]; log_fn(LOG_PROTOCOL_WARN, LD_DIRSERV, "Rejected rend descriptor (length %d) from %s.", (int)body_len, conn->_base.address); write_http_status_line(conn, 400, "Invalid service descriptor rejected"); } else { write_http_status_line(conn, 200, "Service descriptor stored"); } goto done; } /* we didn't recognize the url */ write_http_status_line(conn, 404, "Not found"); done: tor_free(url); return 0; } /** Called when a dirserver receives data on a directory connection; * looks for an HTTP request. If the request is complete, remove it * from the inbuf, try to process it; otherwise, leave it on the * buffer. Return a 0 on success, or -1 on error. */ static int directory_handle_command(dir_connection_t *conn) { char *headers=NULL, *body=NULL; size_t body_len=0; int r; tor_assert(conn); tor_assert(conn->_base.type == CONN_TYPE_DIR); switch (fetch_from_buf_http(conn->_base.inbuf, &headers, MAX_HEADERS_SIZE, &body, &body_len, MAX_BODY_SIZE, 0)) { case -1: /* overflow */ log_warn(LD_DIRSERV, "Invalid input from address '%s'. Closing.", conn->_base.address); return -1; case 0: log_debug(LD_DIRSERV,"command not all here yet."); return 0; /* case 1, fall through */ } http_set_address_origin(headers, TO_CONN(conn)); //log_debug(LD_DIRSERV,"headers %s, body %s.", headers, body); if (!strncasecmp(headers,"GET",3)) r = directory_handle_command_get(conn, headers, body, body_len); else if (!strncasecmp(headers,"POST",4)) r = directory_handle_command_post(conn, headers, body, body_len); else { log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL, "Got headers %s with unknown command. Closing.", escaped(headers)); r = -1; } tor_free(headers); tor_free(body); return r; } /** Write handler for directory connections; called when all data has * been flushed. Close the connection or wait for a response as * appropriate. */ int connection_dir_finished_flushing(dir_connection_t *conn) { tor_assert(conn); tor_assert(conn->_base.type == CONN_TYPE_DIR); switch (conn->_base.state) { case DIR_CONN_STATE_CLIENT_SENDING: log_debug(LD_DIR,"client finished sending command."); conn->_base.state = DIR_CONN_STATE_CLIENT_READING; connection_stop_writing(TO_CONN(conn)); return 0; case DIR_CONN_STATE_SERVER_WRITING: log_debug(LD_DIRSERV,"Finished writing server response. Closing."); connection_mark_for_close(TO_CONN(conn)); return 0; default: log_warn(LD_BUG,"Bug: called in unexpected state %d.", conn->_base.state); tor_fragile_assert(); return -1; } return 0; } /** Connected handler for directory connections: begin sending data to the * server */ int connection_dir_finished_connecting(dir_connection_t *conn) { tor_assert(conn); tor_assert(conn->_base.type == CONN_TYPE_DIR); tor_assert(conn->_base.state == DIR_CONN_STATE_CONNECTING); log_debug(LD_HTTP,"Dir connection to router %s:%u established.", conn->_base.address,conn->_base.port); conn->_base.state = DIR_CONN_STATE_CLIENT_SENDING; /* start flushing conn */ return 0; } /** Called when one or more networkstatus fetches have failed (with uppercase * fingerprints listed in failed). Mark those fingerprints as having * failed once, unless they failed with status code 503. */ static void dir_networkstatus_download_failed(smartlist_t *failed, int status_code) { if (status_code == 503) return; SMARTLIST_FOREACH(failed, const char *, fp, { char digest[DIGEST_LEN]; trusted_dir_server_t *dir; base16_decode(digest, DIGEST_LEN, fp, strlen(fp)); dir = router_get_trusteddirserver_by_digest(digest); if (dir) ++dir->n_networkstatus_failures; }); } /** Called when one or more routerdesc fetches have failed (with uppercase * fingerprints listed in failed). */ static void dir_routerdesc_download_failed(smartlist_t *failed, int status_code) { char digest[DIGEST_LEN]; local_routerstatus_t *rs; time_t now = time(NULL); int server = server_mode(get_options()) && get_options()->DirPort; SMARTLIST_FOREACH(failed, const char *, cp, { base16_decode(digest, DIGEST_LEN, cp, strlen(cp)); rs = router_get_combined_status_by_digest(digest); if (!rs || rs->n_download_failures >= MAX_ROUTERDESC_DOWNLOAD_FAILURES) continue; if (status_code != 503 || server) ++rs->n_download_failures; if (server) { switch (rs->n_download_failures) { case 0: rs->next_attempt_at = 0; break; case 1: rs->next_attempt_at = 0; break; case 2: rs->next_attempt_at = 0; break; case 3: rs->next_attempt_at = now+60; break; case 4: rs->next_attempt_at = now+60; break; case 5: rs->next_attempt_at = now+60*2; break; case 6: rs->next_attempt_at = now+60*5; break; case 7: rs->next_attempt_at = now+60*15; break; default: rs->next_attempt_at = TIME_MAX; break; } } else { switch (rs->n_download_failures) { case 0: rs->next_attempt_at = 0; break; case 1: rs->next_attempt_at = 0; break; case 2: rs->next_attempt_at = now+60; break; case 3: rs->next_attempt_at = now+60*5; break; case 4: rs->next_attempt_at = now+60*10; break; default: rs->next_attempt_at = TIME_MAX; break; } } if (rs->next_attempt_at == 0) log_debug(LD_DIR, "%s failed %d time(s); I'll try again immediately.", cp, (int)rs->n_download_failures); else if (rs->next_attempt_at < TIME_MAX) log_debug(LD_DIR, "%s failed %d time(s); I'll try again in %d seconds.", cp, (int)rs->n_download_failures, (int)(rs->next_attempt_at-now)); else log_debug(LD_DIR, "%s failed %d time(s); Giving up for a while.", cp, (int)rs->n_download_failures); }); /* update_router_descriptor_downloads(time(NULL)); */ } /* Given a directory resource request, containing zero * or more strings separated by plus signs, followed optionally by ".z", store * the strings, in order, into fp_out. If compressed_out is * non-NULL, set it to 1 if the resource ends in ".z", else set it to 0. If * decode_hex is true, then delete all elements that aren't hex digests, and * decode the rest. If sort_uniq is true, then sort the list and remove * all duplicates. */ int dir_split_resource_into_fingerprints(const char *resource, smartlist_t *fp_out, int *compressed_out, int decode_hex, int sort_uniq) { smartlist_t *fp_tmp = smartlist_create(); tor_assert(fp_out); smartlist_split_string(fp_tmp, resource, "+", 0, 0); if (compressed_out) *compressed_out = 0; if (smartlist_len(fp_tmp)) { char *last = smartlist_get(fp_tmp,smartlist_len(fp_tmp)-1); size_t last_len = strlen(last); if (last_len > 2 && !strcmp(last+last_len-2, ".z")) { last[last_len-2] = '\0'; if (compressed_out) *compressed_out = 1; } } if (decode_hex) { int i; char *cp, *d = NULL; for (i = 0; i < smartlist_len(fp_tmp); ++i) { cp = smartlist_get(fp_tmp, i); if (strlen(cp) != HEX_DIGEST_LEN) { log_info(LD_DIR, "Skipping digest %s with non-standard length.", escaped(cp)); smartlist_del_keeporder(fp_tmp, i--); goto again; } d = tor_malloc_zero(DIGEST_LEN); if (base16_decode(d, DIGEST_LEN, cp, HEX_DIGEST_LEN)<0) { log_info(LD_DIR, "Skipping non-decodable digest %s", escaped(cp)); smartlist_del_keeporder(fp_tmp, i--); goto again; } smartlist_set(fp_tmp, i, d); d = NULL; again: tor_free(cp); tor_free(d); } } if (sort_uniq) { smartlist_t *fp_tmp2 = smartlist_create(); int i; if (decode_hex) smartlist_sort_digests(fp_tmp); else smartlist_sort_strings(fp_tmp); if (smartlist_len(fp_tmp)) smartlist_add(fp_tmp2, smartlist_get(fp_tmp, 0)); for (i = 1; i < smartlist_len(fp_tmp); ++i) { char *cp = smartlist_get(fp_tmp, i); char *last = smartlist_get(fp_tmp2, smartlist_len(fp_tmp2)-1); if ((decode_hex && memcmp(cp, last, DIGEST_LEN)) || (!decode_hex && strcasecmp(cp, last))) smartlist_add(fp_tmp2, cp); else tor_free(cp); } smartlist_free(fp_tmp); fp_tmp = fp_tmp2; } smartlist_add_all(fp_out, fp_tmp); smartlist_free(fp_tmp); return 0; }