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- /* Copyright 2001-2004 Roger Dingledine.
- * Copyright 2004-2005 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_trusted_dir(trusted_dir_server_t *dirserv,
- uint8_t purpose, int private_connection,
- const char *resource,
- const char *payload, size_t payload_len);
- 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(connection_t *conn, const char *platform,
- int purpose, const char *resource,
- const char *payload, size_t payload_len);
- static int directory_handle_command(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);
- /********* START VARIABLES **********/
- static addr_policy_t *dir_policy = NULL;
- #if 0 /* commented out for now, since for now what clients send is
- different from what servers want to receive */
- /** URL for publishing rendezvous descriptors. */
- char rend_publish_string[] = "/tor/rendezvous/publish";
- /** Prefix for downloading rendezvous descriptors. */
- char rend_fetch_url[] = "/tor/rendezvous/";
- #endif
- #define ALLOW_DIRECTORY_TIME_SKEW 30*60 /* 30 minutes */
- /********* END VARIABLES ************/
- /** Parse get_options()->DirPolicy, and put the processed version in
- * &dir_policy. Ignore port specifiers.
- */
- void
- parse_dir_policy(void)
- {
- addr_policy_t *n;
- if (dir_policy) {
- addr_policy_free(dir_policy);
- dir_policy = NULL;
- }
- config_parse_addr_policy(get_options()->DirPolicy, &dir_policy);
- /* ports aren't used. */
- for (n=dir_policy; n; n = n->next) {
- n->prt_min = 1;
- n->prt_max = 65535;
- }
- }
- /** Free storage used to hold parsed directory policy */
- void
- free_dir_policy(void)
- {
- addr_policy_free(dir_policy);
- dir_policy = NULL;
- }
- /** Return 1 if <b>addr</b> is permitted to connect to our dir port,
- * based on <b>dir_policy</b>. Else return 0.
- */
- int
- dir_policy_permits_address(uint32_t addr)
- {
- int a;
- if (!dir_policy) /* 'no dir policy' means 'accept' */
- return 1;
- a = router_compare_addr_to_addr_policy(addr, 1, dir_policy);
- if (a==ADDR_POLICY_REJECTED)
- return 0;
- else if (a==ADDR_POLICY_ACCEPTED)
- return 1;
- log_fn(LOG_WARN, "Bug: got unexpected 'maybe' answer from dir policy");
- return 0;
- }
- /** Return true iff the directory purpose 'purpose' must use an
- * anonymous connection to a directory. */
- static int
- purpose_is_private(uint8_t purpose)
- {
- if (purpose == DIR_PURPOSE_FETCH_DIR ||
- purpose == DIR_PURPOSE_UPLOAD_DIR ||
- purpose == DIR_PURPOSE_FETCH_RUNNING_LIST)
- 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;
- router_get_trusted_dir_servers(&dirservers);
- tor_assert(dirservers);
- /* 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,
- {
- /* Pay attention to fascistfirewall when we're uploading a
- * router descriptor, but not when uploading a service
- * descriptor -- those use Tor. */
- if (get_options()->FascistFirewall && purpose == DIR_PURPOSE_UPLOAD_DIR &&
- !get_options()->HttpProxy) {
- if (!smartlist_string_num_isin(get_options()->FirewallPorts, ds->dir_port))
- continue;
- }
- directory_initiate_command_trusted_dir(ds, purpose, purpose_is_private(purpose),
- NULL, payload, payload_len);
- });
- }
- /** Start a connection to a random running directory server, using
- * connection purpose 'purpose' requesting 'resource'. The purpose
- * should be one of 'DIR_PURPOSE_FETCH_DIR',
- * 'DIR_PURPOSE_FETCH_RENDDESC', 'DIR_PURPOSE_FETCH_RUNNING_LIST.'
- * If <b>retry_if_no_servers</b>, 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)
- {
- routerinfo_t *r = NULL;
- trusted_dir_server_t *ds = NULL;
- int fascistfirewall = get_options()->FascistFirewall;
- int directconn = purpose == DIR_PURPOSE_FETCH_DIR ||
- purpose == DIR_PURPOSE_FETCH_RUNNING_LIST;
- int fetch_fresh_first = advertised_server_mode();
- int priv = purpose_is_private(purpose);
- if (directconn) {
- if (fetch_fresh_first) {
- /* only ask authdirservers, and don't ask myself */
- ds = router_pick_trusteddirserver(1, fascistfirewall,
- retry_if_no_servers);
- }
- if (!ds) {
- /* anybody with a non-zero dirport will do */
- r = router_pick_directory_server(1, fascistfirewall,
- purpose==DIR_PURPOSE_FETCH_RUNNING_LIST,
- retry_if_no_servers);
- if (!r) {
- log_fn(LOG_INFO, "No router found for %s; falling back to dirserver list",
- purpose == DIR_PURPOSE_FETCH_RUNNING_LIST
- ? "status list" : "directory");
- ds = router_pick_trusteddirserver(1, fascistfirewall,
- retry_if_no_servers);
- }
- }
- } else { // (purpose == DIR_PURPOSE_FETCH_RENDDESC)
- /* only ask authdirservers, any of them will do */
- /* Never use fascistfirewall; we're going via Tor. */
- ds = router_pick_trusteddirserver(0, 0, retry_if_no_servers);
- }
- if (r)
- directory_initiate_command_router(r, purpose, priv, resource, NULL, 0);
- else if (ds)
- directory_initiate_command_trusted_dir(ds, purpose, priv, resource, NULL, 0);
- else {
- log_fn(LOG_NOTICE,"No running dirservers known. Not trying. (purpose %d)",
- purpose);
- if (directconn) {
- /* remember we tried them all and failed. */
- directory_all_unreachable(time(NULL));
- }
- }
- }
- /** Launch a new connection to the directory server <b>router</b> to upload or
- * download a service or rendezvous descriptor. <b>purpose</b> determines what
- * kind of directory connection we're launching, and must be one of
- * DIR_PURPOSE_{FETCH|UPLOAD}_{DIR|RENDDESC}.
- *
- * When uploading, <b>payload</b> and <b>payload_len</b> determine the content
- * of the HTTP post. Otherwise, <b>payload</b> should be NULL.
- *
- * When fetching a rendezvous descriptor, <b>resource</b> 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->identity_digest,
- purpose, private_connection, resource,
- payload, payload_len);
- }
- /** As directory_initiate_command_router, but send the command to a trusted
- * directory server <b>dirserv</b>. **/
- static void
- directory_initiate_command_trusted_dir(trusted_dir_server_t *dirserv,
- uint8_t purpose, int private_connection,
- const char *resource,
- const char *payload, size_t payload_len)
- {
- directory_initiate_command(dirserv->address, dirserv->addr,dirserv->dir_port,
- NULL, dirserv->digest, purpose, private_connection, resource,
- payload, payload_len);
- }
- /** Called when we are unable to complete our connection to a
- * directory server: Mark the router as down and try again if possible.
- */
- void
- connection_dir_connect_failed(connection_t *conn)
- {
- router_mark_as_down(conn->identity_digest); /* don't try him again */
- if (conn->purpose == DIR_PURPOSE_FETCH_DIR ||
- conn->purpose == DIR_PURPOSE_FETCH_RUNNING_LIST) {
- log_fn(LOG_INFO, "Giving up on directory server at '%s'; retrying",
- conn->address);
- directory_get_from_dirserver(conn->purpose, NULL,
- 0 /* don't retry_if_no_servers */);
- }
- }
- /** Helper for directory_initiate_command_(router|trusted_dir): send the
- * command to a server whose address is <b>address</b>, whose IP is
- * <b>addr</b>, whose directory port is <b>dir_port</b>, whose tor version is
- * <b>platform</b>, and whose identity key digest is <b>digest</b>. The
- * <b>platform</b> 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)
- {
- connection_t *conn;
- tor_assert(address);
- tor_assert(addr);
- tor_assert(dir_port);
- tor_assert(digest);
- switch (purpose) {
- case DIR_PURPOSE_FETCH_DIR:
- log_fn(LOG_DEBUG,"initiating directory fetch");
- break;
- case DIR_PURPOSE_FETCH_RENDDESC:
- log_fn(LOG_DEBUG,"initiating hidden-service descriptor fetch");
- break;
- case DIR_PURPOSE_UPLOAD_DIR:
- log_fn(LOG_DEBUG,"initiating server descriptor upload");
- break;
- case DIR_PURPOSE_UPLOAD_RENDDESC:
- log_fn(LOG_DEBUG,"initiating hidden-service descriptor upload");
- break;
- case DIR_PURPOSE_FETCH_RUNNING_LIST:
- log_fn(LOG_DEBUG,"initiating running-routers fetch");
- break;
- default:
- log_fn(LOG_ERR, "Unrecognized directory connection purpose.");
- tor_assert(0);
- }
- conn = connection_new(CONN_TYPE_DIR);
- /* set up conn so it's got all the data we need to remember */
- conn->addr = addr;
- conn->port = dir_port;
- conn->address = tor_strdup(address);
- memcpy(conn->identity_digest, digest, DIGEST_LEN);
- conn->purpose = purpose;
- /* give it an initial state */
- conn->state = DIR_CONN_STATE_CONNECTING;
- if (!private_connection) {
- /* then we want to connect directly */
- if (get_options()->HttpProxy) {
- addr = get_options()->HttpProxyAddr;
- dir_port = get_options()->HttpProxyPort;
- }
- switch (connection_connect(conn, conn->address, addr, dir_port)) {
- case -1:
- connection_dir_connect_failed(conn);
- connection_free(conn);
- return;
- case 1:
- conn->state = DIR_CONN_STATE_CLIENT_SENDING; /* start flushing conn */
- /* fall through */
- case 0:
- /* queue the command on the outbuf */
- directory_send_command(conn, platform, purpose, resource,
- payload, payload_len);
- connection_watch_events(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->s = connection_ap_make_bridge(conn->address, conn->port);
- if (conn->s < 0) {
- log_fn(LOG_WARN,"Making AP bridge to dirserver failed.");
- connection_mark_for_close(conn);
- return;
- }
- conn->state = DIR_CONN_STATE_CLIENT_SENDING;
- connection_add(conn);
- /* queue the command on the outbuf */
- directory_send_command(conn, platform, purpose, resource,
- payload, payload_len);
- connection_watch_events(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(connection_t *conn, const char *platform,
- int purpose, const char *resource,
- const char *payload, size_t payload_len)
- {
- char tmp[8192];
- char proxystring[256];
- char proxyauthstring[256];
- char hoststring[128];
- char url[128];
- const char *httpcommand = NULL;
- tor_assert(conn);
- tor_assert(conn->type == CONN_TYPE_DIR);
- /* come up with a string for which Host: we want */
- if (conn->port == 80) {
- strlcpy(hoststring, conn->address, sizeof(hoststring));
- } else {
- tor_snprintf(hoststring, sizeof(hoststring),"%s:%d",conn->address, conn->port);
- }
- /* come up with some proxy lines, if we're using one. */
- if (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_fn(LOG_WARN, "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_fn(LOG_DEBUG, "Asking for compressed directory from server running %s",
- platform?platform:"<unknown version>");
- httpcommand = "GET";
- strlcpy(url, "/tor/dir.z", sizeof(url));
- break;
- case DIR_PURPOSE_FETCH_RUNNING_LIST:
- tor_assert(!resource);
- tor_assert(!payload);
- httpcommand = "GET";
- strlcpy(url, "/tor/running-routers", sizeof(url));
- break;
- case DIR_PURPOSE_UPLOAD_DIR:
- tor_assert(!resource);
- tor_assert(payload);
- httpcommand = "POST";
- strlcpy(url, "/tor/", sizeof(url));
- 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";
- tor_snprintf(url, sizeof(url), "/tor/rendezvous/%s", resource);
- break;
- case DIR_PURPOSE_UPLOAD_RENDDESC:
- tor_assert(!resource);
- tor_assert(payload);
- httpcommand = "POST";
- tor_snprintf(url, sizeof(url), "/tor/rendezvous/publish");
- break;
- }
- tor_snprintf(tmp, sizeof(tmp), "%s %s%s HTTP/1.0\r\nContent-Length: %lu\r\nHost: %s%s\r\n\r\n",
- httpcommand,
- proxystring,
- url,
- payload ? (unsigned long)payload_len : 0,
- hoststring,
- proxyauthstring);
- connection_write_to_buf(tmp, strlen(tmp), conn);
- if (payload) {
- /* then send the payload afterwards too */
- connection_write_to_buf(payload, payload_len, conn);
- }
- }
- /** Parse an HTTP request string <b>headers</b> of the form
- * \verbatim
- * "\%s [http[s]://]\%s HTTP/1..."
- * \endverbatim
- * If it's well-formed, strdup the second \%s into *<b>url</b>, and
- * null-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_fn(LOG_DEBUG,"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;
- }
- /** Parse an HTTP response string <b>headers</b> of the form
- * \verbatim
- * "HTTP/1.\%d \%d\%s\r\n...".
- * \endverbatim
- *
- * If it's well-formed, assign the status code to *<b>code</b> and
- * return 0. Otherwise, return -1.
- *
- * On success: If <b>date</b> is provided, set *date to the Date
- * header in the http headers, or 0 if no such header is found. If
- * <b>compression</b> is provided, set *<b>compression</b> 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 <b>reason</b> is provided, strdup the reason string
- * into it.
- */
- int
- parse_http_response(const char *headers, int *code, time_t *date,
- int *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_fn(LOG_WARN,"Failed to parse header '%s'",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 = 0;
- } 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_fn(LOG_INFO, "Unrecognized content encoding: '%s'. Trying to deal.", enc);
- *compression = -1;
- }
- }
- SMARTLIST_FOREACH(parsed_headers, char *, s, tor_free(s));
- smartlist_free(parsed_headers);
- return 0;
- }
- /** Return true iff <b>body</b> 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.
- *
- * Return -1 if an error has occurred, or 0 normally. The caller
- * will take care of marking the connection for close.
- */
- static int
- connection_dir_client_reached_eof(connection_t *conn)
- {
- char *body;
- char *headers;
- char *reason = NULL;
- size_t body_len=0;
- int status_code;
- time_t now, date_header=0;
- int delta;
- int compression;
- int plausible;
- int skewed=0;
- switch (fetch_from_buf_http(conn->inbuf,
- &headers, MAX_HEADERS_SIZE,
- &body, &body_len, MAX_DIR_SIZE)) {
- case -1: /* overflow */
- log_fn(LOG_WARN,"'fetch' response too large (server '%s'). Failing.", conn->address);
- return -1;
- case 0:
- log_fn(LOG_INFO,"'fetch' response not all here, but we're at eof. Closing.");
- return -1;
- /* case 1, fall through */
- }
- if (parse_http_response(headers, &status_code, &date_header,
- &compression, &reason) < 0) {
- log_fn(LOG_WARN,"Unparseable headers (server '%s'). Closing.", conn->address);
- tor_free(body); tor_free(headers);
- return -1;
- }
- if (!reason) reason = tor_strdup("[no reason given]");
- log_fn(LOG_DEBUG,
- "Received response from directory server '%s': %d \"%s\"",
- conn->address, status_code, reason);
- if (date_header > 0) {
- now = time(NULL);
- delta = now-date_header;
- if (abs(delta)>ALLOW_DIRECTORY_TIME_SKEW) {
- log_fn(router_digest_is_trusted_dir(conn->identity_digest) ? LOG_WARN : LOG_INFO,
- "Received directory with skewed time (server '%s'): we are %d minutes %s, or the directory is %d minutes %s.",
- conn->address,
- abs(delta)/60, delta>0 ? "ahead" : "behind",
- abs(delta)/60, delta>0 ? "behind" : "ahead");
- skewed = 1; /* don't check the recommended-versions line */
- } else {
- log_fn(LOG_INFO, "Time on received directory is within tolerance; we are %d seconds skewed. (That's okay.)", delta);
- }
- }
- plausible = body_is_plausible(body, body_len, conn->purpose);
- if (compression || !plausible) {
- char *new_body = NULL;
- size_t new_len = 0;
- int guessed = detect_compression_method(body, body_len);
- if (compression <= 0 || 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 == 0)
- 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_fn(LOG_INFO, "HTTP body from server '%s' was labeled %s, "
- "but it seems to be %s.%s",
- conn->address, description1, description2,
- (compression>0 && guessed>0)?" Trying both.":"");
- }
- /* Try declared compression first if we can. */
- if (compression > 0)
- tor_gzip_uncompress(&new_body, &new_len, body, body_len, compression);
- /* Okay, if that didn't work, and we think that it was compressed
- * differently, try that. */
- if (!new_body && guessed > 0 && compression != guessed)
- tor_gzip_uncompress(&new_body, &new_len, body, body_len, guessed);
- /* 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_WARN, "Unable to decompress HTTP body (server '%s').", conn->address);
- tor_free(body); tor_free(headers); tor_free(reason);
- return -1;
- }
- if (new_body) {
- tor_free(body);
- body = new_body;
- body_len = new_len;
- }
- }
- if (conn->purpose == DIR_PURPOSE_FETCH_DIR) {
- /* fetch/process the directory to learn about new routers. */
- log_fn(LOG_INFO,"Received directory (size %d) from server '%s'",
- (int)body_len, conn->address);
- if (status_code == 503 || body_len == 0) {
- log_fn(LOG_INFO,"Empty directory; status %d (\"%s\") Ignoring.",
- status_code, reason);
- tor_free(body); tor_free(headers); tor_free(reason);
- return 0;
- }
- if (status_code != 200) {
- log_fn(LOG_WARN,"Received http status code %d (\"%s\") from server '%s'. Failing.",
- status_code, reason, conn->address);
- tor_free(body); tor_free(headers); tor_free(reason);
- return -1;
- }
- if (router_load_routerlist_from_directory(body, NULL, !skewed, 0) < 0) {
- log_fn(LOG_NOTICE,"I failed to parse the directory I fetched from %s:%d. Ignoring.", conn->address, conn->port);
- } else {
- log_fn(LOG_INFO,"updated routers.");
- }
- /* do things we've been waiting to do */
- directory_has_arrived(time(NULL), conn->identity_digest);
- }
- if (conn->purpose == DIR_PURPOSE_FETCH_RUNNING_LIST) {
- running_routers_t *rrs;
- routerlist_t *rl;
- /* just update our list of running routers, if this list is new info */
- log_fn(LOG_INFO,"Received running-routers list (size %d)", (int)body_len);
- if (status_code != 200) {
- log_fn(LOG_WARN,"Received http status code %d (\"%s\") from server '%s'. Failing.",
- status_code, reason, conn->address);
- tor_free(body); tor_free(headers); tor_free(reason);
- return -1;
- }
- if (!(rrs = router_parse_runningrouters(body, 1))) {
- log_fn(LOG_WARN, "Can't parse runningrouters list (server '%s')", conn->address);
- tor_free(body); tor_free(headers); tor_free(reason);
- return -1;
- }
- router_get_routerlist(&rl);
- if (rl) {
- routerlist_set_runningrouters(rl,rrs);
- } else {
- running_routers_free(rrs);
- }
- }
- if (conn->purpose == DIR_PURPOSE_UPLOAD_DIR) {
- switch (status_code) {
- case 200:
- log_fn(LOG_INFO,"eof (status 200) after uploading server descriptor: finished.");
- break;
- case 400:
- log_fn(LOG_WARN,"http status 400 (\"%s\") response from dirserver '%s'. Malformed server descriptor?", reason, conn->address);
- break;
- case 403:
- log_fn(LOG_WARN,"http status 403 (\"%s\") response from dirserver '%s'. 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.html#server.", reason, conn->address);
- break;
- default:
- log_fn(LOG_WARN,"http status %d (\"%s\") reason unexpected (server '%s').", status_code, reason, conn->address);
- break;
- }
- }
- if (conn->purpose == DIR_PURPOSE_FETCH_RENDDESC) {
- log_fn(LOG_INFO,"Received rendezvous descriptor (size %d, status %d (\"%s\"))",
- (int)body_len, status_code, reason);
- switch (status_code) {
- case 200:
- if (rend_cache_store(body, body_len) < 0) {
- log_fn(LOG_WARN,"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->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_fn(LOG_WARN,"http status 400 (\"%s\"). Dirserver didn't like our rendezvous query?", reason);
- break;
- default:
- log_fn(LOG_WARN,"http status %d (\"%s\") response unexpected (server '%s').", status_code, reason, conn->address);
- break;
- }
- }
- if (conn->purpose == DIR_PURPOSE_UPLOAD_RENDDESC) {
- switch (status_code) {
- case 200:
- log_fn(LOG_INFO,"Uploading rendezvous descriptor: finished with status 200 (\"%s\")", reason);
- break;
- case 400:
- log_fn(LOG_WARN,"http status 400 (\"%s\") response from dirserver. Malformed rendezvous descriptor?", reason);
- break;
- default:
- log_fn(LOG_WARN,"http status %d (\"%s\") response unexpected (server '%s').", status_code, reason, conn->address);
- break;
- }
- }
- tor_free(body); tor_free(headers); tor_free(reason);
- return 0;
- }
- /** Called when a directory connection reaches EOF */
- int
- connection_dir_reached_eof(connection_t *conn)
- {
- int retval;
- if (conn->state != DIR_CONN_STATE_CLIENT_READING) {
- log_fn(LOG_INFO,"conn reached eof, not reading. Closing.");
- connection_close_immediate(conn); /* it was an error; give up on flushing */
- connection_mark_for_close(conn);
- return -1;
- }
- retval = connection_dir_client_reached_eof(conn);
- connection_mark_for_close(conn);
- return retval;
- }
- /** Read handler for directory connections. (That's connections <em>to</em>
- * directory servers and connections <em>at</em> directory servers.)
- */
- int connection_dir_process_inbuf(connection_t *conn)
- {
- tor_assert(conn);
- tor_assert(conn->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->state == DIR_CONN_STATE_SERVER_COMMAND_WAIT) {
- if (directory_handle_command(conn) < 0) {
- connection_mark_for_close(conn);
- return -1;
- }
- return 0;
- }
- /* XXX for READ states, might want to make sure inbuf isn't too big */
- log_fn(LOG_DEBUG,"Got data, not eof. Leaving on inbuf.");
- return 0;
- }
- /** Create an http response for the client <b>conn</b> out of
- * <b>status</b> and <b>reason_phrase</b>. Write it to <b>conn</b>.
- */
- static void
- write_http_status_line(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_fn(LOG_WARN,"Bug: status line too long.");
- return;
- }
- connection_write_to_buf(buf, strlen(buf), conn);
- }
- /** Helper function: return 1 if there are any dir conns of purpose
- * <b>purpose</b> 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;i<n;i++) {
- conn = carray[i];
- if (conn->type == CONN_TYPE_DIR &&
- conn->purpose == purpose &&
- !conn->marked_for_close &&
- !router_digest_is_me(conn->identity_digest))
- return 1;
- }
- return 0;
- }
- /** 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(connection_t *conn, char *headers,
- char *body, size_t body_len)
- {
- size_t dlen;
- const char *cp;
- char *url;
- char tmp[8192];
- char date[RFC1123_TIME_LEN+1];
- log_fn(LOG_DEBUG,"Received GET command.");
- conn->state = DIR_CONN_STATE_SERVER_WRITING;
- if (parse_http_url(headers, &url) < 0) {
- write_http_status_line(conn, 400, "Bad request");
- return 0;
- }
- log_fn(LOG_INFO,"rewritten url as '%s'.", url);
- if (!strcmp(url,"/tor/") || !strcmp(url,"/tor/dir.z")) { /* directory fetch */
- int deflated = !strcmp(url,"/tor/dir.z");
- dlen = dirserv_get_directory(&cp, deflated);
- tor_free(url);
- if (dlen == 0) {
- log_fn(LOG_NOTICE,"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);
- return 0;
- }
- log_fn(LOG_DEBUG,"Dumping %sdirectory to client.",
- deflated?"deflated ":"");
- format_rfc1123_time(date, time(NULL));
- tor_snprintf(tmp, sizeof(tmp), "HTTP/1.0 200 OK\r\nDate: %s\r\nContent-Length: %d\r\nContent-Type: text/plain\r\nContent-Encoding: %s\r\n\r\n",
- date,
- (int)dlen,
- deflated?"deflate":"identity");
- connection_write_to_buf(tmp, strlen(tmp), conn);
- connection_write_to_buf(cp, dlen, conn);
- return 0;
- }
- if (!strcmp(url,"/tor/running-routers") ||
- !strcmp(url,"/tor/running-routers.z")) { /* running-routers fetch */
- int deflated = !strcmp(url,"/tor/dir.z");
- tor_free(url);
- 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);
- return 0;
- }
- format_rfc1123_time(date, time(NULL));
- tor_snprintf(tmp, sizeof(tmp), "HTTP/1.0 200 OK\r\nDate: %s\r\nContent-Length: %d\r\nContent-Type: text/plain\r\nContent-Encoding: %s\r\n\r\n",
- date,
- (int)dlen,
- deflated?"deflate":"identity");
- connection_write_to_buf(tmp, strlen(tmp), conn);
- connection_write_to_buf(cp, strlen(cp), conn);
- return 0;
- }
- if (!strcmpstart(url,"/tor/rendezvous/")) {
- /* rendezvous descriptor fetch */
- const char *descp;
- size_t desc_len;
- if (!authdir_mode(get_options())) {
- /* We don't hand out rend descs. In fact, it could be a security
- * risk, since rend_cache_lookup_desc() below would provide it
- * if we're gone to the site recently, and 404 if we haven't.
- *
- * Reject. */
- write_http_status_line(conn, 400, "Nonauthoritative directory does not not store rendezvous descriptors.");
- tor_free(url);
- return 0;
- }
- switch (rend_cache_lookup_desc(url+strlen("/tor/rendezvous/"), &descp, &desc_len)) {
- case 1: /* valid */
- format_rfc1123_time(date, time(NULL));
- tor_snprintf(tmp, sizeof(tmp), "HTTP/1.0 200 OK\r\nDate: %s\r\nContent-Length: %d\r\nContent-Type: application/octet-stream\r\n\r\n",
- date,
- (int)desc_len); /* can't include descp here, because it's got nuls */
- connection_write_to_buf(tmp, strlen(tmp), conn);
- connection_write_to_buf(descp, desc_len, 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;
- }
- /* 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(connection_t *conn, char *headers,
- char *body, size_t body_len)
- {
- const char *cp;
- char *url;
- log_fn(LOG_DEBUG,"Received POST command.");
- conn->state = DIR_CONN_STATE_SERVER_WRITING;
- if (!authdir_mode(get_options())) {
- /* we just provide cached directories; we don't want to
- * receive anything. */
- write_http_status_line(conn, 400, "Nonauthoritative directory does not not store server descriptors.");
- return 0;
- }
- if (parse_http_url(headers, &url) < 0) {
- write_http_status_line(conn, 400, "Bad request");
- return 0;
- }
- log_fn(LOG_INFO,"rewritten url as '%s'.", url);
- if (!strcmp(url,"/tor/")) { /* server descriptor post */
- const char *msg;
- cp = body;
- switch (dirserv_add_descriptor(&cp, &msg)) {
- case -2:
- case -1:
- /* malformed descriptor, or something wrong */
- write_http_status_line(conn, 400, msg?msg:"Malformed or unacceptable server descriptor");
- log_fn(LOG_NOTICE,"Rejected descriptor published by '%s'.", conn->address);
- break;
- case 0:
- /* descriptor was well-formed but server has not been approved */
- write_http_status_line(conn, 200, msg?msg:"Unverified server descriptor accepted");
- break;
- case 1:
- dirserv_get_directory(&cp, 0); /* rebuild and write to disk */
- write_http_status_line(conn, 200, msg?msg:"Verified server descriptor accepted");
- break;
- }
- tor_free(url);
- return 0;
- }
- if (!strcmpstart(url,"/tor/rendezvous/publish")) {
- /* rendezvous descriptor post */
- if (rend_cache_store(body, body_len) < 0)
- write_http_status_line(conn, 400, "Invalid service descriptor rejected");
- else
- write_http_status_line(conn, 200, "Service descriptor stored");
- tor_free(url);
- return 0;
- }
- /* we didn't recognize the url */
- write_http_status_line(conn, 404, "Not found");
- 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(connection_t *conn)
- {
- char *headers=NULL, *body=NULL;
- size_t body_len=0;
- int r;
- tor_assert(conn);
- tor_assert(conn->type == CONN_TYPE_DIR);
- switch (fetch_from_buf_http(conn->inbuf,
- &headers, MAX_HEADERS_SIZE,
- &body, &body_len, MAX_BODY_SIZE)) {
- case -1: /* overflow */
- log_fn(LOG_WARN,"Invalid input from address '%s'. Closing.", conn->address);
- return -1;
- case 0:
- log_fn(LOG_DEBUG,"command not all here yet.");
- return 0;
- /* case 1, fall through */
- }
- log_fn(LOG_DEBUG,"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_WARN,"Got headers '%s' with unknown command. Closing.", 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(connection_t *conn)
- {
- tor_assert(conn);
- tor_assert(conn->type == CONN_TYPE_DIR);
- switch (conn->state) {
- case DIR_CONN_STATE_CLIENT_SENDING:
- log_fn(LOG_DEBUG,"client finished sending command.");
- conn->state = DIR_CONN_STATE_CLIENT_READING;
- connection_stop_writing(conn);
- return 0;
- case DIR_CONN_STATE_SERVER_WRITING:
- log_fn(LOG_INFO,"Finished writing server response. Closing.");
- connection_mark_for_close(conn);
- return 0;
- default:
- log_fn(LOG_WARN,"Bug: called in unexpected state %d.", conn->state);
- tor_fragile_assert();
- return -1;
- }
- return 0;
- }
- /** Connected handler for directory connections: begin sending data to the
- * server */
- int
- connection_dir_finished_connecting(connection_t *conn)
- {
- tor_assert(conn);
- tor_assert(conn->type == CONN_TYPE_DIR);
- tor_assert(conn->state == DIR_CONN_STATE_CONNECTING);
- log_fn(LOG_INFO,"Dir connection to router %s:%u established.",
- conn->address,conn->port);
- conn->state = DIR_CONN_STATE_CLIENT_SENDING; /* start flushing conn */
- return 0;
- }
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