[tor-commits] [tor/master] Merge branch 'bug26896_034'
nickm at torproject.org
nickm at torproject.org
Tue Aug 28 16:35:59 UTC 2018
commit 3b960df4f9990355fc2514689280731c31551a4a
Merge: 103dd68ba 21a9d0344
Author: Nick Mathewson <nickm at torproject.org>
Date: Tue Aug 28 12:35:50 2018 -0400
Merge branch 'bug26896_034'
changes/bug26896 | 3 +++
src/feature/dircache/directory.c | 3 +++
2 files changed, 6 insertions(+)
diff --cc src/feature/dircache/directory.c
index a72317618,000000000..888a7c193
mode 100644,000000..100644
--- a/src/feature/dircache/directory.c
+++ b/src/feature/dircache/directory.c
@@@ -1,5966 -1,0 +1,5969 @@@
+/* Copyright (c) 2001-2004, Roger Dingledine.
+ * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
+ * Copyright (c) 2007-2018, The Tor Project, Inc. */
+/* See LICENSE for licensing information */
+
+#define DIRECTORY_PRIVATE
+
+#include "core/or/or.h"
+#include "lib/err/backtrace.h"
+#include "feature/client/bridges.h"
+#include "lib/container/buffers.h"
+#include "core/or/circuitbuild.h"
+#include "app/config/config.h"
+#include "core/mainloop/connection.h"
+#include "core/or/connection_edge.h"
+#include "feature/dircache/conscache.h"
+#include "feature/dircommon/consdiff.h"
+#include "feature/dircache/consdiffmgr.h"
+#include "feature/control/control.h"
+#include "lib/compress/compress.h"
+#include "lib/crypt_ops/crypto_rand.h"
+#include "lib/crypt_ops/crypto_util.h"
+#include "feature/dircache/directory.h"
+#include "feature/dircache/dirserv.h"
+#include "feature/client/entrynodes.h"
+#include "feature/dircommon/fp_pair.h"
+#include "feature/stats/geoip.h"
+#include "feature/hs/hs_cache.h"
+#include "feature/hs/hs_common.h"
+#include "feature/hs/hs_control.h"
+#include "feature/hs/hs_client.h"
+#include "core/mainloop/main.h"
+#include "feature/nodelist/microdesc.h"
+#include "feature/nodelist/networkstatus.h"
+#include "feature/nodelist/nodelist.h"
+#include "core/or/policies.h"
+#include "core/or/relay.h"
+#include "feature/rend/rendclient.h"
+#include "feature/rend/rendcommon.h"
+#include "feature/rend/rendservice.h"
+#include "feature/stats/rephist.h"
+#include "feature/relay/router.h"
+#include "feature/nodelist/routerlist.h"
+#include "feature/nodelist/routerparse.h"
+#include "feature/nodelist/routerset.h"
+#include "lib/encoding/confline.h"
+#include "lib/crypt_ops/crypto_format.h"
+
+#if defined(EXPORTMALLINFO) && defined(HAVE_MALLOC_H) && defined(HAVE_MALLINFO)
+#if !defined(OpenBSD)
+#include <malloc.h>
+#endif
+#endif
+
+#include "feature/dirauth/dirvote.h"
+#include "feature/dirauth/mode.h"
+#include "feature/dirauth/shared_random.h"
+
+#include "feature/nodelist/authority_cert_st.h"
+#include "feature/dircache/cached_dir_st.h"
+#include "feature/dircommon/dir_connection_st.h"
+#include "feature/dirclient/dir_server_st.h"
+#include "core/or/entry_connection_st.h"
+#include "feature/nodelist/networkstatus_st.h"
+#include "feature/nodelist/node_st.h"
+#include "feature/rend/rend_service_descriptor_st.h"
+#include "feature/nodelist/routerinfo_st.h"
+
+/**
+ * \file directory.c
+ * \brief Code to send and fetch information from directory authorities and
+ * caches via HTTP.
+ *
+ * Directory caches and authorities use dirserv.c to generate the results of a
+ * query and stream them to the connection; clients use routerparse.c to parse
+ * them.
+ *
+ * Every directory request has a dir_connection_t on the client side and on
+ * the server side. In most cases, the dir_connection_t object is a linked
+ * connection, tunneled through an edge_connection_t so that it can be a
+ * stream on the Tor network. The only non-tunneled connections are those
+ * that are used to upload material (descriptors and votes) to authorities.
+ * Among tunneled connections, some use one-hop circuits, and others use
+ * multi-hop circuits for anonymity.
+ *
+ * Directory requests are launched by calling
+ * directory_initiate_request(). This
+ * launch the connection, will construct an HTTP request with
+ * directory_send_command(), send the and wait for a response. The client
+ * later handles the response with connection_dir_client_reached_eof(),
+ * which passes the information received to another part of Tor.
+ *
+ * On the server side, requests are read in directory_handle_command(),
+ * which dispatches first on the request type (GET or POST), and then on
+ * the URL requested. GET requests are processed with a table-based
+ * dispatcher in url_table[]. The process of handling larger GET requests
+ * is complicated because we need to avoid allocating a copy of all the
+ * data to be sent to the client in one huge buffer. Instead, we spool the
+ * data into the buffer using logic in connection_dirserv_flushed_some() in
+ * dirserv.c. (TODO: If we extended buf.c to have a zero-copy
+ * reference-based buffer type, we could remove most of that code, at the
+ * cost of a bit more reference counting.)
+ **/
+
+/* 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_send_command(dir_connection_t *conn,
+ int direct,
+ const directory_request_t *request);
+static int body_is_plausible(const char *body, size_t body_len, int purpose);
+static void http_set_address_origin(const char *headers, connection_t *conn);
+static void connection_dir_download_routerdesc_failed(dir_connection_t *conn);
+static void connection_dir_bridge_routerdesc_failed(dir_connection_t *conn);
+static void connection_dir_download_cert_failed(
+ dir_connection_t *conn, int status_code);
+static void connection_dir_retry_bridges(smartlist_t *descs);
+static void dir_routerdesc_download_failed(smartlist_t *failed,
+ int status_code,
+ int router_purpose,
+ int was_extrainfo,
+ int was_descriptor_digests);
+static void dir_microdesc_download_failed(smartlist_t *failed,
+ int status_code,
+ const char *dir_id);
+static int client_likes_consensus(const struct consensus_cache_entry_t *ent,
+ const char *want_url);
+
+static void connection_dir_close_consensus_fetches(
+ dir_connection_t *except_this_one, const char *resource);
+
+/********* START VARIABLES **********/
+
+/** Maximum size, in bytes, for resized buffers. */
+#define MAX_BUF_SIZE ((1<<24)-1) /* 16MB-1 */
+/** Maximum size, in bytes, for any directory object that we've downloaded. */
+#define MAX_DIR_DL_SIZE MAX_BUF_SIZE
+
+/** Maximum size, in bytes, for any directory object that we're accepting
+ * as an upload. */
+#define MAX_DIR_UL_SIZE MAX_BUF_SIZE
+
+/** 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: "
+#define X_OR_DIFF_FROM_CONSENSUS_HEADER "X-Or-Diff-From-Consensus: "
+
+/** HTTP cache control: how long do we tell proxies they can cache each
+ * kind of document we serve? */
+#define FULL_DIR_CACHE_LIFETIME (60*60)
+#define RUNNINGROUTERS_CACHE_LIFETIME (20*60)
+#define DIRPORTFRONTPAGE_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)
+#define MICRODESC_CACHE_LIFETIME (48*60*60)
+
+/********* END VARIABLES ************/
+
+/** Convert a connection_t* to a dir_connection_t*; assert if the cast is
+ * invalid. */
+dir_connection_t *
+TO_DIR_CONN(connection_t *c)
+{
+ tor_assert(c->magic == DIR_CONNECTION_MAGIC);
+ return DOWNCAST(dir_connection_t, c);
+}
+
+/** Return false if the directory purpose <b>dir_purpose</b>
+ * does not require an anonymous (three-hop) connection.
+ *
+ * Return true 1) by default, 2) if all directory actions have
+ * specifically been configured to be over an anonymous connection,
+ * or 3) if the router is a bridge */
+int
+purpose_needs_anonymity(uint8_t dir_purpose, uint8_t router_purpose,
+ const char *resource)
+{
+ if (get_options()->AllDirActionsPrivate)
+ return 1;
+
+ if (router_purpose == ROUTER_PURPOSE_BRIDGE) {
+ if (dir_purpose == DIR_PURPOSE_FETCH_SERVERDESC
+ && resource && !strcmp(resource, "authority.z")) {
+ /* We are asking a bridge for its own descriptor. That doesn't need
+ anonymity. */
+ return 0;
+ }
+ /* Assume all other bridge stuff needs anonymity. */
+ return 1; /* if no circuits yet, this might break bootstrapping, but it's
+ * needed to be safe. */
+ }
+
+ switch (dir_purpose)
+ {
+ case DIR_PURPOSE_UPLOAD_DIR:
+ case DIR_PURPOSE_UPLOAD_VOTE:
+ case DIR_PURPOSE_UPLOAD_SIGNATURES:
+ case DIR_PURPOSE_FETCH_STATUS_VOTE:
+ case DIR_PURPOSE_FETCH_DETACHED_SIGNATURES:
+ case DIR_PURPOSE_FETCH_CONSENSUS:
+ case DIR_PURPOSE_FETCH_CERTIFICATE:
+ case DIR_PURPOSE_FETCH_SERVERDESC:
+ case DIR_PURPOSE_FETCH_EXTRAINFO:
+ case DIR_PURPOSE_FETCH_MICRODESC:
+ return 0;
+ case DIR_PURPOSE_HAS_FETCHED_HSDESC:
+ case DIR_PURPOSE_HAS_FETCHED_RENDDESC_V2:
+ case DIR_PURPOSE_UPLOAD_RENDDESC_V2:
+ case DIR_PURPOSE_FETCH_RENDDESC_V2:
+ case DIR_PURPOSE_FETCH_HSDESC:
+ case DIR_PURPOSE_UPLOAD_HSDESC:
+ return 1;
+ case DIR_PURPOSE_SERVER:
+ default:
+ log_warn(LD_BUG, "Called with dir_purpose=%d, router_purpose=%d",
+ dir_purpose, router_purpose);
+ tor_assert_nonfatal_unreached();
+ return 1; /* Assume it needs anonymity; better safe than sorry. */
+ }
+}
+
+/** Return a newly allocated string describing <b>auth</b>. Only describes
+ * authority features. */
+STATIC char *
+authdir_type_to_string(dirinfo_type_t auth)
+{
+ char *result;
+ smartlist_t *lst = smartlist_new();
+ if (auth & V3_DIRINFO)
+ smartlist_add(lst, (void*)"V3");
+ if (auth & BRIDGE_DIRINFO)
+ smartlist_add(lst, (void*)"Bridge");
+ if (smartlist_len(lst)) {
+ result = smartlist_join_strings(lst, ", ", 0, NULL);
+ } else {
+ result = tor_strdup("[Not an authority]");
+ }
+ smartlist_free(lst);
+ return result;
+}
+
+/** Return a string describing a given directory connection purpose. */
+STATIC const char *
+dir_conn_purpose_to_string(int purpose)
+{
+ switch (purpose)
+ {
+ case DIR_PURPOSE_UPLOAD_DIR:
+ return "server descriptor upload";
+ case DIR_PURPOSE_UPLOAD_VOTE:
+ return "server vote upload";
+ case DIR_PURPOSE_UPLOAD_SIGNATURES:
+ return "consensus signature upload";
+ case DIR_PURPOSE_FETCH_SERVERDESC:
+ return "server descriptor fetch";
+ case DIR_PURPOSE_FETCH_EXTRAINFO:
+ return "extra-info fetch";
+ case DIR_PURPOSE_FETCH_CONSENSUS:
+ return "consensus network-status fetch";
+ case DIR_PURPOSE_FETCH_CERTIFICATE:
+ return "authority cert fetch";
+ case DIR_PURPOSE_FETCH_STATUS_VOTE:
+ return "status vote fetch";
+ case DIR_PURPOSE_FETCH_DETACHED_SIGNATURES:
+ return "consensus signature fetch";
+ case DIR_PURPOSE_FETCH_RENDDESC_V2:
+ return "hidden-service v2 descriptor fetch";
+ case DIR_PURPOSE_UPLOAD_RENDDESC_V2:
+ return "hidden-service v2 descriptor upload";
+ case DIR_PURPOSE_FETCH_HSDESC:
+ return "hidden-service descriptor fetch";
+ case DIR_PURPOSE_UPLOAD_HSDESC:
+ return "hidden-service descriptor upload";
+ case DIR_PURPOSE_FETCH_MICRODESC:
+ return "microdescriptor fetch";
+ }
+
+ log_warn(LD_BUG, "Called with unknown purpose %d", purpose);
+ return "(unknown)";
+}
+
+/** Return the requisite directory information types. */
+STATIC dirinfo_type_t
+dir_fetch_type(int dir_purpose, int router_purpose, const char *resource)
+{
+ dirinfo_type_t type;
+ switch (dir_purpose) {
+ case DIR_PURPOSE_FETCH_EXTRAINFO:
+ type = EXTRAINFO_DIRINFO;
+ if (router_purpose == ROUTER_PURPOSE_BRIDGE)
+ type |= BRIDGE_DIRINFO;
+ else
+ type |= V3_DIRINFO;
+ break;
+ case DIR_PURPOSE_FETCH_SERVERDESC:
+ if (router_purpose == ROUTER_PURPOSE_BRIDGE)
+ type = BRIDGE_DIRINFO;
+ else
+ type = V3_DIRINFO;
+ break;
+ case DIR_PURPOSE_FETCH_STATUS_VOTE:
+ case DIR_PURPOSE_FETCH_DETACHED_SIGNATURES:
+ case DIR_PURPOSE_FETCH_CERTIFICATE:
+ type = V3_DIRINFO;
+ break;
+ case DIR_PURPOSE_FETCH_CONSENSUS:
+ type = V3_DIRINFO;
+ if (resource && !strcmp(resource, "microdesc"))
+ type |= MICRODESC_DIRINFO;
+ break;
+ case DIR_PURPOSE_FETCH_MICRODESC:
+ type = MICRODESC_DIRINFO;
+ break;
+ default:
+ log_warn(LD_BUG, "Unexpected purpose %d", (int)dir_purpose);
+ type = NO_DIRINFO;
+ break;
+ }
+ return type;
+}
+
+/** Return true iff <b>identity_digest</b> is the digest of a router which
+ * says that it caches extrainfos. (If <b>is_authority</b> we always
+ * believe that to be true.) */
+int
+router_supports_extrainfo(const char *identity_digest, int is_authority)
+{
+ const node_t *node = node_get_by_id(identity_digest);
+
+ if (node && node->ri) {
+ if (node->ri->caches_extra_info)
+ return 1;
+ }
+ if (is_authority) {
+ return 1;
+ }
+ return 0;
+}
+
+/** Return true iff any trusted directory authority has accepted our
+ * server descriptor.
+ *
+ * We consider any authority sufficient because waiting for all of
+ * them means it never happens while any authority is down; we don't
+ * go for something more complex in the middle (like \>1/3 or \>1/2 or
+ * \>=1/2) because that doesn't seem necessary yet.
+ */
+int
+directories_have_accepted_server_descriptor(void)
+{
+ const smartlist_t *servers = router_get_trusted_dir_servers();
+ const or_options_t *options = get_options();
+ SMARTLIST_FOREACH(servers, dir_server_t *, d, {
+ if ((d->type & options->PublishServerDescriptor_) &&
+ d->has_accepted_serverdesc) {
+ return 1;
+ }
+ });
+ return 0;
+}
+
+/** Start a connection to every suitable directory authority, using
+ * connection purpose <b>dir_purpose</b> and uploading <b>payload</b>
+ * (of length <b>payload_len</b>). The dir_purpose should be one of
+ * 'DIR_PURPOSE_UPLOAD_{DIR|VOTE|SIGNATURES}'.
+ *
+ * <b>router_purpose</b> describes the type of descriptor we're
+ * publishing, if we're publishing a descriptor -- e.g. general or bridge.
+ *
+ * <b>type</b> specifies what sort of dir authorities (V3,
+ * BRIDGE, etc) we should upload to.
+ *
+ * If <b>extrainfo_len</b> is nonzero, the first <b>payload_len</b> bytes of
+ * <b>payload</b> hold a router descriptor, and the next <b>extrainfo_len</b>
+ * bytes of <b>payload</b> hold an extra-info document. Upload the descriptor
+ * to all authorities, and the extra-info document to all authorities that
+ * support it.
+ */
+void
+directory_post_to_dirservers(uint8_t dir_purpose, uint8_t router_purpose,
+ dirinfo_type_t type,
+ const char *payload,
+ size_t payload_len, size_t extrainfo_len)
+{
+ const or_options_t *options = get_options();
+ dir_indirection_t indirection;
+ const smartlist_t *dirservers = router_get_trusted_dir_servers();
+ int found = 0;
+ const int exclude_self = (dir_purpose == DIR_PURPOSE_UPLOAD_VOTE ||
+ dir_purpose == DIR_PURPOSE_UPLOAD_SIGNATURES);
+ 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_BEGIN(dirservers, dir_server_t *, ds) {
+ routerstatus_t *rs = &(ds->fake_status);
+ size_t upload_len = payload_len;
+
+ if ((type & ds->type) == 0)
+ continue;
+
+ if (exclude_self && router_digest_is_me(ds->digest)) {
+ /* we don't upload to ourselves, but at least there's now at least
+ * one authority of this type that has what we wanted to upload. */
+ found = 1;
+ continue;
+ }
+
+ if (options->StrictNodes &&
+ routerset_contains_routerstatus(options->ExcludeNodes, rs, -1)) {
+ log_warn(LD_DIR, "Wanted to contact authority '%s' for %s, but "
+ "it's in our ExcludedNodes list and StrictNodes is set. "
+ "Skipping.",
+ ds->nickname,
+ dir_conn_purpose_to_string(dir_purpose));
+ continue;
+ }
+
+ found = 1; /* at least one authority of this type was listed */
+ if (dir_purpose == DIR_PURPOSE_UPLOAD_DIR)
+ ds->has_accepted_serverdesc = 0;
+
+ if (extrainfo_len && router_supports_extrainfo(ds->digest, 1)) {
+ upload_len += extrainfo_len;
+ log_info(LD_DIR, "Uploading an extrainfo too (length %d)",
+ (int) extrainfo_len);
+ }
+ if (purpose_needs_anonymity(dir_purpose, router_purpose, NULL)) {
+ indirection = DIRIND_ANONYMOUS;
+ } else if (!fascist_firewall_allows_dir_server(ds,
+ FIREWALL_DIR_CONNECTION,
+ 0)) {
+ if (fascist_firewall_allows_dir_server(ds, FIREWALL_OR_CONNECTION, 0))
+ indirection = DIRIND_ONEHOP;
+ else
+ indirection = DIRIND_ANONYMOUS;
+ } else {
+ indirection = DIRIND_DIRECT_CONN;
+ }
+
+ directory_request_t *req = directory_request_new(dir_purpose);
+ directory_request_set_routerstatus(req, rs);
+ directory_request_set_router_purpose(req, router_purpose);
+ directory_request_set_indirection(req, indirection);
+ directory_request_set_payload(req, payload, upload_len);
+ directory_initiate_request(req);
+ directory_request_free(req);
+ } SMARTLIST_FOREACH_END(ds);
+ if (!found) {
+ char *s = authdir_type_to_string(type);
+ log_warn(LD_DIR, "Publishing server descriptor to directory authorities "
+ "of type '%s', but no authorities of that type listed!", s);
+ tor_free(s);
+ }
+}
+
+/** Return true iff, according to the values in <b>options</b>, we should be
+ * using directory guards for direct downloads of directory information. */
+STATIC int
+should_use_directory_guards(const or_options_t *options)
+{
+ /* Public (non-bridge) servers never use directory guards. */
+ if (public_server_mode(options))
+ return 0;
+ /* If guards are disabled, we can't use directory guards.
+ */
+ if (!options->UseEntryGuards)
+ return 0;
+ /* If we're configured to fetch directory info aggressively or of a
+ * nonstandard type, don't use directory guards. */
+ if (options->DownloadExtraInfo || options->FetchDirInfoEarly ||
+ options->FetchDirInfoExtraEarly || options->FetchUselessDescriptors)
+ return 0;
+ return 1;
+}
+
+/** Pick an unconstrained directory server from among our guards, the latest
+ * networkstatus, or the fallback dirservers, for use in downloading
+ * information of type <b>type</b>, and return its routerstatus. */
+static const routerstatus_t *
+directory_pick_generic_dirserver(dirinfo_type_t type, int pds_flags,
+ uint8_t dir_purpose,
+ circuit_guard_state_t **guard_state_out)
+{
+ const routerstatus_t *rs = NULL;
+ const or_options_t *options = get_options();
+
+ if (options->UseBridges)
+ log_warn(LD_BUG, "Called when we have UseBridges set.");
+
+ if (should_use_directory_guards(options)) {
+ const node_t *node = guards_choose_dirguard(dir_purpose, guard_state_out);
+ if (node)
+ rs = node->rs;
+ } else {
+ /* anybody with a non-zero dirport will do */
+ rs = router_pick_directory_server(type, pds_flags);
+ }
+ if (!rs) {
+ log_info(LD_DIR, "No router found for %s; falling back to "
+ "dirserver list.", dir_conn_purpose_to_string(dir_purpose));
+ rs = router_pick_fallback_dirserver(type, pds_flags);
+ }
+
+ return rs;
+}
+
+/**
+ * Set the extra fields in <b>req</b> that are used when requesting a
+ * consensus of type <b>resource</b>.
+ *
+ * Right now, these fields are if-modified-since and x-or-diff-from-consensus.
+ */
+static void
+dir_consensus_request_set_additional_headers(directory_request_t *req,
+ const char *resource)
+{
+ time_t if_modified_since = 0;
+ uint8_t or_diff_from[DIGEST256_LEN];
+ int or_diff_from_is_set = 0;
+
+ /* DEFAULT_IF_MODIFIED_SINCE_DELAY is 1/20 of the default consensus
+ * period of 1 hour.
+ */
+ const int DEFAULT_IF_MODIFIED_SINCE_DELAY = 180;
+ const int32_t DEFAULT_TRY_DIFF_FOR_CONSENSUS_NEWER = 72;
+ const int32_t MIN_TRY_DIFF_FOR_CONSENSUS_NEWER = 0;
+ const int32_t MAX_TRY_DIFF_FOR_CONSENSUS_NEWER = 8192;
+ const char TRY_DIFF_FOR_CONSENSUS_NEWER_NAME[] =
+ "try-diff-for-consensus-newer-than";
+
+ int flav = FLAV_NS;
+ if (resource)
+ flav = networkstatus_parse_flavor_name(resource);
+
+ int32_t max_age_for_diff = 3600 *
+ networkstatus_get_param(NULL,
+ TRY_DIFF_FOR_CONSENSUS_NEWER_NAME,
+ DEFAULT_TRY_DIFF_FOR_CONSENSUS_NEWER,
+ MIN_TRY_DIFF_FOR_CONSENSUS_NEWER,
+ MAX_TRY_DIFF_FOR_CONSENSUS_NEWER);
+
+ if (flav != -1) {
+ /* IF we have a parsed consensus of this type, we can do an
+ * if-modified-time based on it. */
+ networkstatus_t *v;
+ v = networkstatus_get_latest_consensus_by_flavor(flav);
+ if (v) {
+ /* In networks with particularly short V3AuthVotingIntervals,
+ * ask for the consensus if it's been modified since half the
+ * V3AuthVotingInterval of the most recent consensus. */
+ time_t ims_delay = DEFAULT_IF_MODIFIED_SINCE_DELAY;
+ if (v->fresh_until > v->valid_after
+ && ims_delay > (v->fresh_until - v->valid_after)/2) {
+ ims_delay = (v->fresh_until - v->valid_after)/2;
+ }
+ if_modified_since = v->valid_after + ims_delay;
+ if (v->valid_after >= approx_time() - max_age_for_diff) {
+ memcpy(or_diff_from, v->digest_sha3_as_signed, DIGEST256_LEN);
+ or_diff_from_is_set = 1;
+ }
+ }
+ } else {
+ /* Otherwise it might be a consensus we don't parse, but which we
+ * do cache. Look at the cached copy, perhaps. */
+ cached_dir_t *cd = dirserv_get_consensus(resource);
+ /* We have no method of determining the voting interval from an
+ * unparsed consensus, so we use the default. */
+ if (cd) {
+ if_modified_since = cd->published + DEFAULT_IF_MODIFIED_SINCE_DELAY;
+ if (cd->published >= approx_time() - max_age_for_diff) {
+ memcpy(or_diff_from, cd->digest_sha3_as_signed, DIGEST256_LEN);
+ or_diff_from_is_set = 1;
+ }
+ }
+ }
+
+ if (if_modified_since > 0)
+ directory_request_set_if_modified_since(req, if_modified_since);
+ if (or_diff_from_is_set) {
+ char hex[HEX_DIGEST256_LEN + 1];
+ base16_encode(hex, sizeof(hex),
+ (const char*)or_diff_from, sizeof(or_diff_from));
+ directory_request_add_header(req, X_OR_DIFF_FROM_CONSENSUS_HEADER, hex);
+ }
+}
+
+/** Start a connection to a random running directory server, using
+ * connection purpose <b>dir_purpose</b>, intending to fetch descriptors
+ * of purpose <b>router_purpose</b>, and requesting <b>resource</b>.
+ * Use <b>pds_flags</b> as arguments to router_pick_directory_server()
+ * or router_pick_trusteddirserver().
+ */
+MOCK_IMPL(void,
+directory_get_from_dirserver,(
+ uint8_t dir_purpose,
+ uint8_t router_purpose,
+ const char *resource,
+ int pds_flags,
+ download_want_authority_t want_authority))
+{
+ const routerstatus_t *rs = NULL;
+ const or_options_t *options = get_options();
+ int prefer_authority = (directory_fetches_from_authorities(options)
+ || want_authority == DL_WANT_AUTHORITY);
+ int require_authority = 0;
+ int get_via_tor = purpose_needs_anonymity(dir_purpose, router_purpose,
+ resource);
+ dirinfo_type_t type = dir_fetch_type(dir_purpose, router_purpose, resource);
+
+ if (type == NO_DIRINFO)
+ return;
+
+ if (!options->FetchServerDescriptors)
+ return;
+
+ circuit_guard_state_t *guard_state = NULL;
+ if (!get_via_tor) {
+ if (options->UseBridges && !(type & BRIDGE_DIRINFO)) {
+ /* We want to ask a running bridge for which we have a descriptor.
+ *
+ * When we ask choose_random_entry() for a bridge, we specify what
+ * sort of dir fetch we'll be doing, so it won't return a bridge
+ * that can't answer our question.
+ */
+ const node_t *node = guards_choose_dirguard(dir_purpose, &guard_state);
+ if (node && node->ri) {
+ /* every bridge has a routerinfo. */
+ routerinfo_t *ri = node->ri;
+ /* clients always make OR connections to bridges */
+ tor_addr_port_t or_ap;
+ directory_request_t *req = directory_request_new(dir_purpose);
+ /* we are willing to use a non-preferred address if we need to */
+ fascist_firewall_choose_address_node(node, FIREWALL_OR_CONNECTION, 0,
+ &or_ap);
+ directory_request_set_or_addr_port(req, &or_ap);
+ directory_request_set_directory_id_digest(req,
+ ri->cache_info.identity_digest);
+ directory_request_set_router_purpose(req, router_purpose);
+ directory_request_set_resource(req, resource);
+ if (dir_purpose == DIR_PURPOSE_FETCH_CONSENSUS)
+ dir_consensus_request_set_additional_headers(req, resource);
+ directory_request_set_guard_state(req, guard_state);
+ directory_initiate_request(req);
+ directory_request_free(req);
+ } else {
+ if (guard_state) {
+ entry_guard_cancel(&guard_state);
+ }
+ log_notice(LD_DIR, "Ignoring directory request, since no bridge "
+ "nodes are available yet.");
+ }
+
+ return;
+ } else {
+ if (prefer_authority || (type & BRIDGE_DIRINFO)) {
+ /* only ask authdirservers, and don't ask myself */
+ rs = router_pick_trusteddirserver(type, pds_flags);
+ if (rs == NULL && (pds_flags & (PDS_NO_EXISTING_SERVERDESC_FETCH|
+ PDS_NO_EXISTING_MICRODESC_FETCH))) {
+ /* We don't want to fetch from any authorities that we're currently
+ * fetching server descriptors from, and we got no match. Did we
+ * get no match because all the authorities have connections
+ * fetching server descriptors (in which case we should just
+ * return,) or because all the authorities are down or on fire or
+ * unreachable or something (in which case we should go on with
+ * our fallback code)? */
+ pds_flags &= ~(PDS_NO_EXISTING_SERVERDESC_FETCH|
+ PDS_NO_EXISTING_MICRODESC_FETCH);
+ rs = router_pick_trusteddirserver(type, pds_flags);
+ if (rs) {
+ log_debug(LD_DIR, "Deferring serverdesc fetch: all authorities "
+ "are in use.");
+ return;
+ }
+ }
+ if (rs == NULL && require_authority) {
+ log_info(LD_DIR, "No authorities were available for %s: will try "
+ "later.", dir_conn_purpose_to_string(dir_purpose));
+ return;
+ }
+ }
+ if (!rs && !(type & BRIDGE_DIRINFO)) {
+ rs = directory_pick_generic_dirserver(type, pds_flags,
+ dir_purpose,
+ &guard_state);
+ if (!rs)
+ get_via_tor = 1; /* last resort: try routing it via Tor */
+ }
+ }
+ }
+
+ if (get_via_tor) {
+ /* Never use fascistfirewall; we're going via Tor. */
+ pds_flags |= PDS_IGNORE_FASCISTFIREWALL;
+ rs = router_pick_directory_server(type, pds_flags);
+ }
+
+ /* 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) {
+ const dir_indirection_t indirection =
+ get_via_tor ? DIRIND_ANONYMOUS : DIRIND_ONEHOP;
+ directory_request_t *req = directory_request_new(dir_purpose);
+ directory_request_set_routerstatus(req, rs);
+ directory_request_set_router_purpose(req, router_purpose);
+ directory_request_set_indirection(req, indirection);
+ directory_request_set_resource(req, resource);
+ if (dir_purpose == DIR_PURPOSE_FETCH_CONSENSUS)
+ dir_consensus_request_set_additional_headers(req, resource);
+ if (guard_state)
+ directory_request_set_guard_state(req, guard_state);
+ directory_initiate_request(req);
+ directory_request_free(req);
+ } else {
+ log_notice(LD_DIR,
+ "While fetching directory info, "
+ "no running dirservers known. Will try again later. "
+ "(purpose %d)", dir_purpose);
+ if (!purpose_needs_anonymity(dir_purpose, router_purpose, resource)) {
+ /* remember we tried them all and failed. */
+ directory_all_unreachable(time(NULL));
+ }
+ }
+}
+
+/** As directory_get_from_dirserver, but initiates a request to <i>every</i>
+ * directory authority other than ourself. Only for use by authorities when
+ * searching for missing information while voting. */
+void
+directory_get_from_all_authorities(uint8_t dir_purpose,
+ uint8_t router_purpose,
+ const char *resource)
+{
+ tor_assert(dir_purpose == DIR_PURPOSE_FETCH_STATUS_VOTE ||
+ dir_purpose == DIR_PURPOSE_FETCH_DETACHED_SIGNATURES);
+
+ SMARTLIST_FOREACH_BEGIN(router_get_trusted_dir_servers(),
+ dir_server_t *, ds) {
+ if (router_digest_is_me(ds->digest))
+ continue;
+ if (!(ds->type & V3_DIRINFO))
+ continue;
+ const routerstatus_t *rs = &ds->fake_status;
+ directory_request_t *req = directory_request_new(dir_purpose);
+ directory_request_set_routerstatus(req, rs);
+ directory_request_set_router_purpose(req, router_purpose);
+ directory_request_set_resource(req, resource);
+ directory_initiate_request(req);
+ directory_request_free(req);
+ } SMARTLIST_FOREACH_END(ds);
+}
+
+/** Return true iff <b>ind</b> requires a multihop circuit. */
+static int
+dirind_is_anon(dir_indirection_t ind)
+{
+ return ind == DIRIND_ANON_DIRPORT || ind == DIRIND_ANONYMOUS;
+}
+
+/* Choose reachable OR and Dir addresses and ports from status, copying them
+ * into use_or_ap and use_dir_ap. If indirection is anonymous, then we're
+ * connecting via another relay, so choose the primary IPv4 address and ports.
+ *
+ * status should have at least one reachable address, if we can't choose a
+ * reachable address, warn and return -1. Otherwise, return 0.
+ */
+static int
+directory_choose_address_routerstatus(const routerstatus_t *status,
+ dir_indirection_t indirection,
+ tor_addr_port_t *use_or_ap,
+ tor_addr_port_t *use_dir_ap)
+{
+ tor_assert(status != NULL);
+ tor_assert(use_or_ap != NULL);
+ tor_assert(use_dir_ap != NULL);
+
+ const or_options_t *options = get_options();
+ int have_or = 0, have_dir = 0;
+
+ /* We expect status to have at least one reachable address if we're
+ * connecting to it directly.
+ *
+ * Therefore, we can simply use the other address if the one we want isn't
+ * allowed by the firewall.
+ *
+ * (When Tor uploads and downloads a hidden service descriptor, it uses
+ * DIRIND_ANONYMOUS, except for Tor2Web, which uses DIRIND_ONEHOP.
+ * So this code will only modify the address for Tor2Web's HS descriptor
+ * fetches. Even Single Onion Servers (NYI) use DIRIND_ANONYMOUS, to avoid
+ * HSDirs denying service by rejecting descriptors.)
+ */
+
+ /* Initialise the OR / Dir addresses */
+ tor_addr_make_null(&use_or_ap->addr, AF_UNSPEC);
+ use_or_ap->port = 0;
+ tor_addr_make_null(&use_dir_ap->addr, AF_UNSPEC);
+ use_dir_ap->port = 0;
+
+ /* ORPort connections */
+ if (indirection == DIRIND_ANONYMOUS) {
+ if (status->addr) {
+ /* Since we're going to build a 3-hop circuit and ask the 2nd relay
+ * to extend to this address, always use the primary (IPv4) OR address */
+ tor_addr_from_ipv4h(&use_or_ap->addr, status->addr);
+ use_or_ap->port = status->or_port;
+ have_or = 1;
+ }
+ } else if (indirection == DIRIND_ONEHOP) {
+ /* We use an IPv6 address if we have one and we prefer it.
+ * Use the preferred address and port if they are reachable, otherwise,
+ * use the alternate address and port (if any).
+ */
+ fascist_firewall_choose_address_rs(status, FIREWALL_OR_CONNECTION, 0,
+ use_or_ap);
+ have_or = tor_addr_port_is_valid_ap(use_or_ap, 0);
+ }
+
+ /* DirPort connections
+ * DIRIND_ONEHOP uses ORPort, but may fall back to the DirPort on relays */
+ if (indirection == DIRIND_DIRECT_CONN ||
+ indirection == DIRIND_ANON_DIRPORT ||
+ (indirection == DIRIND_ONEHOP
+ && !directory_must_use_begindir(options))) {
+ fascist_firewall_choose_address_rs(status, FIREWALL_DIR_CONNECTION, 0,
+ use_dir_ap);
+ have_dir = tor_addr_port_is_valid_ap(use_dir_ap, 0);
+ }
+
+ /* We rejected all addresses in the relay's status. This means we can't
+ * connect to it. */
+ if (!have_or && !have_dir) {
+ static int logged_backtrace = 0;
+ log_info(LD_BUG, "Rejected all OR and Dir addresses from %s when "
+ "launching an outgoing directory connection to: IPv4 %s OR %d "
+ "Dir %d IPv6 %s OR %d Dir %d", routerstatus_describe(status),
+ fmt_addr32(status->addr), status->or_port,
+ status->dir_port, fmt_addr(&status->ipv6_addr),
+ status->ipv6_orport, status->dir_port);
+ if (!logged_backtrace) {
+ log_backtrace(LOG_INFO, LD_BUG, "Addresses came from");
+ logged_backtrace = 1;
+ }
+ return -1;
+ }
+
+ return 0;
+}
+
+/** Return true iff <b>conn</b> 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")) {
+ const routerinfo_t *me = router_get_my_routerinfo();
+ if (me &&
+ router_digest_is_me(conn->identity_digest) &&
+ tor_addr_eq_ipv4h(&conn->base_.addr, me->addr) && /*XXXX prop 118*/
+ 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.
+ */
+static void
+connection_dir_request_failed(dir_connection_t *conn)
+{
+ if (conn->guard_state) {
+ /* We haven't seen a success on this guard state, so consider it to have
+ * failed. */
+ entry_guard_failed(&conn->guard_state);
+ }
+ if (directory_conn_is_self_reachability_test(conn)) {
+ return; /* this was a test fetch. don't retry. */
+ }
+ if (!entry_list_is_constrained(get_options()))
+ router_set_status(conn->identity_digest, 0); /* don't try this one again */
+ if (conn->base_.purpose == DIR_PURPOSE_FETCH_SERVERDESC ||
+ conn->base_.purpose == DIR_PURPOSE_FETCH_EXTRAINFO) {
+ log_info(LD_DIR, "Giving up on serverdesc/extrainfo fetch from "
+ "directory server at '%s'; retrying",
+ conn->base_.address);
+ if (conn->router_purpose == ROUTER_PURPOSE_BRIDGE)
+ connection_dir_bridge_routerdesc_failed(conn);
+ connection_dir_download_routerdesc_failed(conn);
+ } else if (conn->base_.purpose == DIR_PURPOSE_FETCH_CONSENSUS) {
+ if (conn->requested_resource)
+ networkstatus_consensus_download_failed(0, conn->requested_resource);
+ } else if (conn->base_.purpose == DIR_PURPOSE_FETCH_CERTIFICATE) {
+ log_info(LD_DIR, "Giving up on certificate fetch from directory server "
+ "at '%s'; retrying",
+ conn->base_.address);
+ connection_dir_download_cert_failed(conn, 0);
+ } else if (conn->base_.purpose == DIR_PURPOSE_FETCH_DETACHED_SIGNATURES) {
+ log_info(LD_DIR, "Giving up downloading detached signatures from '%s'",
+ conn->base_.address);
+ } else if (conn->base_.purpose == DIR_PURPOSE_FETCH_STATUS_VOTE) {
+ log_info(LD_DIR, "Giving up downloading votes from '%s'",
+ conn->base_.address);
+ } else if (conn->base_.purpose == DIR_PURPOSE_FETCH_MICRODESC) {
+ log_info(LD_DIR, "Giving up on downloading microdescriptors from "
+ "directory server at '%s'; will retry", conn->base_.address);
+ connection_dir_download_routerdesc_failed(conn);
+ }
+}
+
+/** Helper: Attempt to fetch directly the descriptors of each bridge
+ * listed in <b>failed</b>.
+ */
+static void
+connection_dir_retry_bridges(smartlist_t *descs)
+{
+ char digest[DIGEST_LEN];
+ SMARTLIST_FOREACH(descs, const char *, cp,
+ {
+ if (base16_decode(digest, DIGEST_LEN, cp, strlen(cp)) != DIGEST_LEN) {
+ log_warn(LD_BUG, "Malformed fingerprint in list: %s",
+ escaped(cp));
+ continue;
+ }
+ retry_bridge_descriptor_fetch_directly(digest);
+ });
+}
+
+/** Called when an attempt to download one or more router descriptors
+ * or extra-info documents on connection <b>conn</b> failed.
+ */
+static void
+connection_dir_download_routerdesc_failed(dir_connection_t *conn)
+{
+ /* No need to increment the failure count for routerdescs, since
+ * it's not their fault. */
+
+ /* No need to relaunch descriptor downloads here: we already do it
+ * every 10 or 60 seconds (FOO_DESCRIPTOR_RETRY_INTERVAL) in main.c. */
+ tor_assert(conn->base_.purpose == DIR_PURPOSE_FETCH_SERVERDESC ||
+ conn->base_.purpose == DIR_PURPOSE_FETCH_EXTRAINFO ||
+ conn->base_.purpose == DIR_PURPOSE_FETCH_MICRODESC);
+
+ (void) conn;
+}
+
+/** Called when an attempt to download a bridge's routerdesc from
+ * one of the authorities failed due to a network error. If
+ * possible attempt to download descriptors from the bridge directly.
+ */
+static void
+connection_dir_bridge_routerdesc_failed(dir_connection_t *conn)
+{
+ smartlist_t *which = NULL;
+
+ /* Requests for bridge descriptors are in the form 'fp/', so ignore
+ anything else. */
+ if (!conn->requested_resource || strcmpstart(conn->requested_resource,"fp/"))
+ return;
+
+ which = smartlist_new();
+ dir_split_resource_into_fingerprints(conn->requested_resource
+ + strlen("fp/"),
+ which, NULL, 0);
+
+ tor_assert(conn->base_.purpose != DIR_PURPOSE_FETCH_EXTRAINFO);
+ if (smartlist_len(which)) {
+ connection_dir_retry_bridges(which);
+ SMARTLIST_FOREACH(which, char *, cp, tor_free(cp));
+ }
+ smartlist_free(which);
+}
+
+/** Called when an attempt to fetch a certificate fails. */
+static void
+connection_dir_download_cert_failed(dir_connection_t *conn, int status)
+{
+ const char *fp_pfx = "fp/";
+ const char *fpsk_pfx = "fp-sk/";
+ smartlist_t *failed;
+ tor_assert(conn->base_.purpose == DIR_PURPOSE_FETCH_CERTIFICATE);
+
+ if (!conn->requested_resource)
+ return;
+ failed = smartlist_new();
+ /*
+ * We have two cases download by fingerprint (resource starts
+ * with "fp/") or download by fingerprint/signing key pair
+ * (resource starts with "fp-sk/").
+ */
+ if (!strcmpstart(conn->requested_resource, fp_pfx)) {
+ /* Download by fingerprint case */
+ dir_split_resource_into_fingerprints(conn->requested_resource +
+ strlen(fp_pfx),
+ failed, NULL, DSR_HEX);
+ SMARTLIST_FOREACH_BEGIN(failed, char *, cp) {
+ /* Null signing key digest indicates download by fp only */
+ authority_cert_dl_failed(cp, NULL, status);
+ tor_free(cp);
+ } SMARTLIST_FOREACH_END(cp);
+ } else if (!strcmpstart(conn->requested_resource, fpsk_pfx)) {
+ /* Download by (fp,sk) pairs */
+ dir_split_resource_into_fingerprint_pairs(conn->requested_resource +
+ strlen(fpsk_pfx), failed);
+ SMARTLIST_FOREACH_BEGIN(failed, fp_pair_t *, cp) {
+ authority_cert_dl_failed(cp->first, cp->second, status);
+ tor_free(cp);
+ } SMARTLIST_FOREACH_END(cp);
+ } else {
+ log_warn(LD_DIR,
+ "Don't know what to do with failure for cert fetch %s",
+ conn->requested_resource);
+ }
+
+ smartlist_free(failed);
+
+ update_certificate_downloads(time(NULL));
+}
+
+/* Should this tor instance only use begindir for all its directory requests?
+ */
+int
+directory_must_use_begindir(const or_options_t *options)
+{
+ /* Clients, onion services, and bridges must use begindir,
+ * relays and authorities do not have to */
+ return !public_server_mode(options);
+}
+
+/** Evaluate the situation and decide if we should use an encrypted
+ * "begindir-style" connection for this directory request.
+ * 0) If there is no DirPort, yes.
+ * 1) If or_port is 0, or it's a direct conn and or_port is firewalled
+ * or we're a dir mirror, no.
+ * 2) If we prefer to avoid begindir conns, and we're not fetching or
+ * publishing a bridge relay descriptor, no.
+ * 3) Else yes.
+ * If returning 0, return in *reason why we can't use begindir.
+ * reason must not be NULL.
+ */
+static int
+directory_command_should_use_begindir(const or_options_t *options,
+ const directory_request_t *req,
+ const char **reason)
+{
+ const tor_addr_t *or_addr = &req->or_addr_port.addr;
+ //const tor_addr_t *dir_addr = &req->dir_addr_port.addr;
+ const int or_port = req->or_addr_port.port;
+ const int dir_port = req->dir_addr_port.port;
+
+ const dir_indirection_t indirection = req->indirection;
+
+ tor_assert(reason);
+ *reason = NULL;
+
+ /* Reasons why we must use begindir */
+ if (!dir_port) {
+ *reason = "(using begindir - directory with no DirPort)";
+ return 1; /* We don't know a DirPort -- must begindir. */
+ }
+ /* Reasons why we can't possibly use begindir */
+ if (!or_port) {
+ *reason = "directory with unknown ORPort";
+ return 0; /* We don't know an ORPort -- no chance. */
+ }
+ if (indirection == DIRIND_DIRECT_CONN ||
+ indirection == DIRIND_ANON_DIRPORT) {
+ *reason = "DirPort connection";
+ return 0;
+ }
+ if (indirection == DIRIND_ONEHOP) {
+ /* We're firewalled and want a direct OR connection */
+ if (!fascist_firewall_allows_address_addr(or_addr, or_port,
+ FIREWALL_OR_CONNECTION, 0, 0)) {
+ *reason = "ORPort not reachable";
+ return 0;
+ }
+ }
+ /* Reasons why we want to avoid using begindir */
+ if (indirection == DIRIND_ONEHOP) {
+ if (!directory_must_use_begindir(options)) {
+ *reason = "in relay mode";
+ return 0;
+ }
+ }
+ /* DIRIND_ONEHOP on a client, or DIRIND_ANONYMOUS
+ */
+ *reason = "(using begindir)";
+ return 1;
+}
+
+/**
+ * Create and return a new directory_request_t with purpose
+ * <b>dir_purpose</b>.
+ */
+directory_request_t *
+directory_request_new(uint8_t dir_purpose)
+{
+ tor_assert(dir_purpose >= DIR_PURPOSE_MIN_);
+ tor_assert(dir_purpose <= DIR_PURPOSE_MAX_);
+ tor_assert(dir_purpose != DIR_PURPOSE_SERVER);
+ tor_assert(dir_purpose != DIR_PURPOSE_HAS_FETCHED_RENDDESC_V2);
+ tor_assert(dir_purpose != DIR_PURPOSE_HAS_FETCHED_HSDESC);
+
+ directory_request_t *result = tor_malloc_zero(sizeof(*result));
+ tor_addr_make_null(&result->or_addr_port.addr, AF_INET);
+ result->or_addr_port.port = 0;
+ tor_addr_make_null(&result->dir_addr_port.addr, AF_INET);
+ result->dir_addr_port.port = 0;
+ result->dir_purpose = dir_purpose;
+ result->router_purpose = ROUTER_PURPOSE_GENERAL;
+ result->indirection = DIRIND_ONEHOP;
+ return result;
+}
+/**
+ * Release all resources held by <b>req</b>.
+ */
+void
+directory_request_free_(directory_request_t *req)
+{
+ if (req == NULL)
+ return;
+ config_free_lines(req->additional_headers);
+ tor_free(req);
+}
+/**
+ * Set the address and OR port to use for this directory request. If there is
+ * no OR port, we'll have to connect over the dirport. (If there are both,
+ * the indirection setting determines which to use.)
+ */
+void
+directory_request_set_or_addr_port(directory_request_t *req,
+ const tor_addr_port_t *p)
+{
+ memcpy(&req->or_addr_port, p, sizeof(*p));
+}
+/**
+ * Set the address and dirport to use for this directory request. If there
+ * is no dirport, we'll have to connect over the OR port. (If there are both,
+ * the indirection setting determines which to use.)
+ */
+void
+directory_request_set_dir_addr_port(directory_request_t *req,
+ const tor_addr_port_t *p)
+{
+ memcpy(&req->dir_addr_port, p, sizeof(*p));
+}
+/**
+ * Set the RSA identity digest of the directory to use for this directory
+ * request.
+ */
+void
+directory_request_set_directory_id_digest(directory_request_t *req,
+ const char *digest)
+{
+ memcpy(req->digest, digest, DIGEST_LEN);
+}
+/**
+ * Set the router purpose associated with uploaded and downloaded router
+ * descriptors and extrainfo documents in this directory request. The purpose
+ * must be one of ROUTER_PURPOSE_GENERAL (the default) or
+ * ROUTER_PURPOSE_BRIDGE.
+ */
+void
+directory_request_set_router_purpose(directory_request_t *req,
+ uint8_t router_purpose)
+{
+ tor_assert(router_purpose == ROUTER_PURPOSE_GENERAL ||
+ router_purpose == ROUTER_PURPOSE_BRIDGE);
+ // assert that it actually makes sense to set this purpose, given
+ // the dir_purpose.
+ req->router_purpose = router_purpose;
+}
+/**
+ * Set the indirection to be used for the directory request. The indirection
+ * parameter configures whether to connect to a DirPort or ORPort, and whether
+ * to anonymize the connection. DIRIND_ONEHOP (use ORPort, don't anonymize)
+ * is the default. See dir_indirection_t for more information.
+ */
+void
+directory_request_set_indirection(directory_request_t *req,
+ dir_indirection_t indirection)
+{
+ req->indirection = indirection;
+}
+
+/**
+ * Set a pointer to the resource to request from a directory. Different
+ * request types use resources to indicate different components of their URL.
+ * Note that only an alias to <b>resource</b> is stored, so the
+ * <b>resource</b> must outlive the request.
+ */
+void
+directory_request_set_resource(directory_request_t *req,
+ const char *resource)
+{
+ req->resource = resource;
+}
+/**
+ * Set a pointer to the payload to include with this directory request, along
+ * with its length. Note that only an alias to <b>payload</b> is stored, so
+ * the <b>payload</b> must outlive the request.
+ */
+void
+directory_request_set_payload(directory_request_t *req,
+ const char *payload,
+ size_t payload_len)
+{
+ tor_assert(DIR_PURPOSE_IS_UPLOAD(req->dir_purpose));
+
+ req->payload = payload;
+ req->payload_len = payload_len;
+}
+/**
+ * Set an if-modified-since date to send along with the request. The
+ * default is 0 (meaning, send no if-modified-since header).
+ */
+void
+directory_request_set_if_modified_since(directory_request_t *req,
+ time_t if_modified_since)
+{
+ req->if_modified_since = if_modified_since;
+}
+
+/** Include a header of name <b>key</b> with content <b>val</b> in the
+ * request. Neither may include newlines or other odd characters. Their
+ * ordering is not currently guaranteed.
+ *
+ * Note that, as elsewhere in this module, header keys include a trailing
+ * colon and space.
+ */
+void
+directory_request_add_header(directory_request_t *req,
+ const char *key,
+ const char *val)
+{
+ config_line_prepend(&req->additional_headers, key, val);
+}
+/**
+ * Set an object containing HS data to be associated with this request. Note
+ * that only an alias to <b>query</b> is stored, so the <b>query</b> object
+ * must outlive the request.
+ */
+void
+directory_request_set_rend_query(directory_request_t *req,
+ const rend_data_t *query)
+{
+ if (query) {
+ tor_assert(req->dir_purpose == DIR_PURPOSE_FETCH_RENDDESC_V2 ||
+ req->dir_purpose == DIR_PURPOSE_UPLOAD_RENDDESC_V2);
+ }
+ req->rend_query = query;
+}
+/**
+ * Set an object containing HS connection identifier to be associated with
+ * this request. Note that only an alias to <b>ident</b> is stored, so the
+ * <b>ident</b> object must outlive the request.
+ */
+void
+directory_request_upload_set_hs_ident(directory_request_t *req,
+ const hs_ident_dir_conn_t *ident)
+{
+ if (ident) {
+ tor_assert(req->dir_purpose == DIR_PURPOSE_UPLOAD_HSDESC);
+ }
+ req->hs_ident = ident;
+}
+/**
+ * Set an object containing HS connection identifier to be associated with
+ * this fetch request. Note that only an alias to <b>ident</b> is stored, so
+ * the <b>ident</b> object must outlive the request.
+ */
+void
+directory_request_fetch_set_hs_ident(directory_request_t *req,
+ const hs_ident_dir_conn_t *ident)
+{
+ if (ident) {
+ tor_assert(req->dir_purpose == DIR_PURPOSE_FETCH_HSDESC);
+ }
+ req->hs_ident = ident;
+}
+/** Set a static circuit_guard_state_t object to affliate with the request in
+ * <b>req</b>. This object will receive notification when the attempt to
+ * connect to the guard either succeeds or fails. */
+void
+directory_request_set_guard_state(directory_request_t *req,
+ circuit_guard_state_t *state)
+{
+ req->guard_state = state;
+}
+
+/**
+ * Internal: Return true if any information for contacting the directory in
+ * <b>req</b> has been set, other than by the routerstatus. */
+static int
+directory_request_dir_contact_info_specified(const directory_request_t *req)
+{
+ /* We only check for ports here, since we don't use an addr unless the port
+ * is set */
+ return (req->or_addr_port.port ||
+ req->dir_addr_port.port ||
+ ! tor_digest_is_zero(req->digest));
+}
+
+/**
+ * Set the routerstatus to use for the directory associated with this
+ * request. If this option is set, then no other function to set the
+ * directory's address or identity should be called.
+ */
+void
+directory_request_set_routerstatus(directory_request_t *req,
+ const routerstatus_t *status)
+{
+ req->routerstatus = status;
+}
+/**
+ * Helper: update the addresses, ports, and identities in <b>req</b>
+ * from the routerstatus object in <b>req</b>. Return 0 on success.
+ * On failure, warn and return -1.
+ */
+static int
+directory_request_set_dir_from_routerstatus(directory_request_t *req)
+
+{
+ const routerstatus_t *status = req->routerstatus;
+ if (BUG(status == NULL))
+ return -1;
+ const or_options_t *options = get_options();
+ const node_t *node;
+ tor_addr_port_t use_or_ap, use_dir_ap;
+ const int anonymized_connection = dirind_is_anon(req->indirection);
+
+ tor_assert(status != NULL);
+
+ node = node_get_by_id(status->identity_digest);
+
+ /* XXX The below check is wrong: !node means it's not in the consensus,
+ * but we haven't checked if we have a descriptor for it -- and also,
+ * we only care about the descriptor if it's a begindir-style anonymized
+ * connection. */
+ if (!node && anonymized_connection) {
+ log_info(LD_DIR, "Not sending anonymized request to directory '%s'; we "
+ "don't have its router descriptor.",
+ routerstatus_describe(status));
+ return -1;
+ }
+
+ if (options->ExcludeNodes && options->StrictNodes &&
+ routerset_contains_routerstatus(options->ExcludeNodes, status, -1)) {
+ log_warn(LD_DIR, "Wanted to contact directory mirror %s for %s, but "
+ "it's in our ExcludedNodes list and StrictNodes is set. "
+ "Skipping. This choice might make your Tor not work.",
+ routerstatus_describe(status),
+ dir_conn_purpose_to_string(req->dir_purpose));
+ return -1;
+ }
+
+ /* At this point, if we are a client making a direct connection to a
+ * directory server, we have selected a server that has at least one address
+ * allowed by ClientUseIPv4/6 and Reachable{"",OR,Dir}Addresses. This
+ * selection uses the preference in ClientPreferIPv6{OR,Dir}Port, if
+ * possible. (If UseBridges is set, clients always use IPv6, and prefer it
+ * by default.)
+ *
+ * Now choose an address that we can use to connect to the directory server.
+ */
+ if (directory_choose_address_routerstatus(status,
+ req->indirection, &use_or_ap,
+ &use_dir_ap) < 0) {
+ return -1;
+ }
+
+ directory_request_set_or_addr_port(req, &use_or_ap);
+ directory_request_set_dir_addr_port(req, &use_dir_ap);
+ directory_request_set_directory_id_digest(req, status->identity_digest);
+ return 0;
+}
+
+/**
+ * Launch the provided directory request, configured in <b>request</b>.
+ * After this function is called, you can free <b>request</b>.
+ */
+MOCK_IMPL(void,
+directory_initiate_request,(directory_request_t *request))
+{
+ tor_assert(request);
+ if (request->routerstatus) {
+ tor_assert_nonfatal(
+ ! directory_request_dir_contact_info_specified(request));
+ if (directory_request_set_dir_from_routerstatus(request) < 0) {
+ return;
+ }
+ }
+
+ const tor_addr_port_t *or_addr_port = &request->or_addr_port;
+ const tor_addr_port_t *dir_addr_port = &request->dir_addr_port;
+ const char *digest = request->digest;
+ const uint8_t dir_purpose = request->dir_purpose;
+ const uint8_t router_purpose = request->router_purpose;
+ const dir_indirection_t indirection = request->indirection;
+ const char *resource = request->resource;
+ const rend_data_t *rend_query = request->rend_query;
+ const hs_ident_dir_conn_t *hs_ident = request->hs_ident;
+ circuit_guard_state_t *guard_state = request->guard_state;
+
+ tor_assert(or_addr_port->port || dir_addr_port->port);
+ tor_assert(digest);
+
+ dir_connection_t *conn;
+ const or_options_t *options = get_options();
+ int socket_error = 0;
+ const char *begindir_reason = NULL;
+ /* Should the connection be to a relay's OR port (and inside that we will
+ * send our directory request)? */
+ const int use_begindir =
+ directory_command_should_use_begindir(options, request, &begindir_reason);
+
+ /* Will the connection go via a three-hop Tor circuit? Note that this
+ * is separate from whether it will use_begindir. */
+ const int anonymized_connection = dirind_is_anon(indirection);
+
+ /* What is the address we want to make the directory request to? If
+ * we're making a begindir request this is the ORPort of the relay
+ * we're contacting; if not a begindir request, this is its DirPort.
+ * Note that if anonymized_connection is true, we won't be initiating
+ * a connection directly to this address. */
+ tor_addr_t addr;
+ tor_addr_copy(&addr, &(use_begindir ? or_addr_port : dir_addr_port)->addr);
+ uint16_t port = (use_begindir ? or_addr_port : dir_addr_port)->port;
+
+ log_debug(LD_DIR, "anonymized %d, use_begindir %d.",
+ anonymized_connection, use_begindir);
+
+ log_debug(LD_DIR, "Initiating %s", dir_conn_purpose_to_string(dir_purpose));
+
+ if (purpose_needs_anonymity(dir_purpose, router_purpose, resource)) {
+ tor_assert(anonymized_connection ||
+ rend_non_anonymous_mode_enabled(options));
+ }
+
+ /* use encrypted begindir connections for everything except relays
+ * this provides better protection for directory fetches */
+ if (!use_begindir && directory_must_use_begindir(options)) {
+ log_warn(LD_BUG, "Client could not use begindir connection: %s",
+ begindir_reason ? begindir_reason : "(NULL)");
+ return;
+ }
+
+ /* ensure that we don't make direct connections when a SOCKS server is
+ * configured. */
+ if (!anonymized_connection && !use_begindir && !options->HTTPProxy &&
+ (options->Socks4Proxy || options->Socks5Proxy)) {
+ log_warn(LD_DIR, "Cannot connect to a directory server through a "
+ "SOCKS proxy!");
+ return;
+ }
+
+ /* Make sure that the destination addr and port we picked is viable. */
+ if (!port || tor_addr_is_null(&addr)) {
+ static int logged_backtrace = 0;
+ log_warn(LD_DIR,
+ "Cannot make an outgoing %sconnection without a remote %sPort.",
+ use_begindir ? "begindir " : "",
+ use_begindir ? "OR" : "Dir");
+ if (!logged_backtrace) {
+ log_backtrace(LOG_INFO, LD_BUG, "Address came from");
+ logged_backtrace = 1;
+ }
+ return;
+ }
+
+ conn = dir_connection_new(tor_addr_family(&addr));
+
+ /* set up conn so it's got all the data we need to remember */
+ tor_addr_copy(&conn->base_.addr, &addr);
+ conn->base_.port = port;
+ conn->base_.address = tor_addr_to_str_dup(&addr);
+ memcpy(conn->identity_digest, digest, DIGEST_LEN);
+
+ conn->base_.purpose = dir_purpose;
+ conn->router_purpose = router_purpose;
+
+ /* give it an initial state */
+ conn->base_.state = DIR_CONN_STATE_CONNECTING;
+
+ /* decide whether we can learn our IP address from this conn */
+ /* XXXX This is a bad name for this field now. */
+ conn->dirconn_direct = !anonymized_connection;
+
+ /* copy rendezvous data, if any */
+ if (rend_query) {
+ /* We can't have both v2 and v3+ identifier. */
+ tor_assert_nonfatal(!hs_ident);
+ conn->rend_data = rend_data_dup(rend_query);
+ }
+ if (hs_ident) {
+ /* We can't have both v2 and v3+ identifier. */
+ tor_assert_nonfatal(!rend_query);
+ conn->hs_ident = hs_ident_dir_conn_dup(hs_ident);
+ }
+
+ if (!anonymized_connection && !use_begindir) {
+ /* then we want to connect to dirport directly */
+
+ if (options->HTTPProxy) {
+ tor_addr_copy(&addr, &options->HTTPProxyAddr);
+ port = options->HTTPProxyPort;
+ }
+
+ // In this case we should not have picked a directory guard.
+ if (BUG(guard_state)) {
+ entry_guard_cancel(&guard_state);
+ }
+
+ switch (connection_connect(TO_CONN(conn), conn->base_.address, &addr,
+ port, &socket_error)) {
+ case -1:
+ connection_mark_for_close(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, 1, request);
+ connection_watch_events(TO_CONN(conn), READ_EVENT | WRITE_EVENT);
+ /* writable indicates finish, readable indicates broken link,
+ error indicates broken link in windowsland. */
+ }
+ } else {
+ /* We will use a Tor circuit (maybe 1-hop, maybe 3-hop, maybe with
+ * begindir, maybe not with begindir) */
+
+ entry_connection_t *linked_conn;
+
+ /* Anonymized tunneled connections can never share a circuit.
+ * One-hop directory connections can share circuits with each other
+ * but nothing else. */
+ int iso_flags = anonymized_connection ? ISO_STREAM : ISO_SESSIONGRP;
+
+ /* If it's an anonymized connection, remember the fact that we
+ * wanted it for later: maybe we'll want it again soon. */
+ if (anonymized_connection && use_begindir)
+ rep_hist_note_used_internal(time(NULL), 0, 1);
+ else if (anonymized_connection && !use_begindir)
+ rep_hist_note_used_port(time(NULL), conn->base_.port);
+
+ // In this case we should not have a directory guard; we'll
+ // get a regular guard later when we build the circuit.
+ if (BUG(anonymized_connection && guard_state)) {
+ entry_guard_cancel(&guard_state);
+ }
+
+ conn->guard_state = guard_state;
+
+ /* make an AP connection
+ * populate it and add it at the right state
+ * hook up both sides
+ */
+ linked_conn =
+ connection_ap_make_link(TO_CONN(conn),
+ conn->base_.address, conn->base_.port,
+ digest,
+ SESSION_GROUP_DIRCONN, iso_flags,
+ use_begindir, !anonymized_connection);
+ if (!linked_conn) {
+ log_warn(LD_NET,"Making tunnel 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 connection for link 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, 0, request);
+
+ connection_watch_events(TO_CONN(conn), READ_EVENT|WRITE_EVENT);
+ connection_start_reading(ENTRY_TO_CONN(linked_conn));
+ }
+}
+
+/** Return true iff anything we say on <b>conn</b> is being encrypted before
+ * we send it to the client/server. */
+int
+connection_dir_is_encrypted(const dir_connection_t *conn)
+{
+ /* Right now it's sufficient to see if conn is or has been linked, since
+ * the only thing it could be linked to is an edge connection on a
+ * circuit, and the only way it could have been unlinked is at the edge
+ * connection getting closed.
+ */
+ return TO_CONN(conn)->linked;
+}
+
+/** Helper for sorting
+ *
+ * sort strings alphabetically
+ */
+static int
+compare_strs_(const void **a, const void **b)
+{
+ const char *s1 = *a, *s2 = *b;
+ return strcmp(s1, s2);
+}
+
+#define CONDITIONAL_CONSENSUS_FPR_LEN 3
+#if (CONDITIONAL_CONSENSUS_FPR_LEN > DIGEST_LEN)
+#error "conditional consensus fingerprint length is larger than digest length"
+#endif
+
+/** Return the URL we should use for a consensus download.
+ *
+ * Use the "conditional consensus downloading" feature described in
+ * dir-spec.txt, i.e.
+ * GET .../consensus/<b>fpr</b>+<b>fpr</b>+<b>fpr</b>
+ *
+ * If 'resource' is provided, it is the name of a consensus flavor to request.
+ */
+static char *
+directory_get_consensus_url(const char *resource)
+{
+ char *url = NULL;
+ const char *hyphen, *flavor;
+ if (resource==NULL || strcmp(resource, "ns")==0) {
+ flavor = ""; /* Request ns consensuses as "", so older servers will work*/
+ hyphen = "";
+ } else {
+ flavor = resource;
+ hyphen = "-";
+ }
+
+ {
+ char *authority_id_list;
+ smartlist_t *authority_digests = smartlist_new();
+
+ SMARTLIST_FOREACH_BEGIN(router_get_trusted_dir_servers(),
+ dir_server_t *, ds) {
+ char *hex;
+ if (!(ds->type & V3_DIRINFO))
+ continue;
+
+ hex = tor_malloc(2*CONDITIONAL_CONSENSUS_FPR_LEN+1);
+ base16_encode(hex, 2*CONDITIONAL_CONSENSUS_FPR_LEN+1,
+ ds->v3_identity_digest, CONDITIONAL_CONSENSUS_FPR_LEN);
+ smartlist_add(authority_digests, hex);
+ } SMARTLIST_FOREACH_END(ds);
+ smartlist_sort(authority_digests, compare_strs_);
+ authority_id_list = smartlist_join_strings(authority_digests,
+ "+", 0, NULL);
+
+ tor_asprintf(&url, "/tor/status-vote/current/consensus%s%s/%s.z",
+ hyphen, flavor, authority_id_list);
+
+ SMARTLIST_FOREACH(authority_digests, char *, cp, tor_free(cp));
+ smartlist_free(authority_digests);
+ tor_free(authority_id_list);
+ }
+ return url;
+}
+
+/**
+ * Copies the ipv6 from source to destination, subject to buffer size limit
+ * size. If decorate is true, makes sure the copied address is decorated.
+ */
+static void
+copy_ipv6_address(char* destination, const char* source, size_t len,
+ int decorate) {
+ tor_assert(destination);
+ tor_assert(source);
+
+ if (decorate && source[0] != '[') {
+ tor_snprintf(destination, len, "[%s]", source);
+ } else {
+ strlcpy(destination, source, len);
+ }
+}
+
+/** Queue an appropriate HTTP command for <b>request</b> on
+ * <b>conn</b>-\>outbuf. If <b>direct</b> is true, we're making a
+ * non-anonymized connection to the dirport.
+ */
+static void
+directory_send_command(dir_connection_t *conn,
+ const int direct,
+ const directory_request_t *req)
+{
+ tor_assert(req);
+ const int purpose = req->dir_purpose;
+ const char *resource = req->resource;
+ const char *payload = req->payload;
+ const size_t payload_len = req->payload_len;
+ const time_t if_modified_since = req->if_modified_since;
+ const int anonymized_connection = dirind_is_anon(req->indirection);
+
+ char proxystring[256];
+ char hoststring[128];
+ /* NEEDS to be the same size hoststring.
+ Will be decorated with brackets around it if it is ipv6. */
+ char decorated_address[128];
+ smartlist_t *headers = smartlist_new();
+ char *url;
+ char *accept_encoding;
+ size_t url_len;
+ char request[8192];
+ size_t request_len, total_request_len = 0;
+ const char *httpcommand = NULL;
+
+ tor_assert(conn);
+ tor_assert(conn->base_.type == CONN_TYPE_DIR);
+
+ tor_free(conn->requested_resource);
+ if (resource)
+ conn->requested_resource = tor_strdup(resource);
+
+ /* decorate the ip address if it is ipv6 */
+ if (strchr(conn->base_.address, ':')) {
+ copy_ipv6_address(decorated_address, conn->base_.address,
+ sizeof(decorated_address), 1);
+ } else {
+ strlcpy(decorated_address, conn->base_.address, sizeof(decorated_address));
+ }
+
+ /* come up with a string for which Host: we want */
+ if (conn->base_.port == 80) {
+ strlcpy(hoststring, decorated_address, sizeof(hoststring));
+ } else {
+ tor_snprintf(hoststring, sizeof(hoststring), "%s:%d",
+ decorated_address, conn->base_.port);
+ }
+
+ /* Format if-modified-since */
+ if (if_modified_since) {
+ char b[RFC1123_TIME_LEN+1];
+ format_rfc1123_time(b, if_modified_since);
+ smartlist_add_asprintf(headers, "If-Modified-Since: %s\r\n", b);
+ }
+
+ /* 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) {
+ smartlist_add_asprintf(headers,
+ "Proxy-Authorization: Basic %s\r\n",
+ base64_authenticator);
+ tor_free(base64_authenticator);
+ }
+ } else {
+ proxystring[0] = 0;
+ }
+
+ if (! anonymized_connection) {
+ /* Add Accept-Encoding. */
+ accept_encoding = accept_encoding_header();
+ smartlist_add_asprintf(headers, "Accept-Encoding: %s\r\n",
+ accept_encoding);
+ tor_free(accept_encoding);
+ }
+
+ /* Add additional headers, if any */
+ {
+ config_line_t *h;
+ for (h = req->additional_headers; h; h = h->next) {
+ smartlist_add_asprintf(headers, "%s%s\r\n", h->key, h->value);
+ }
+ }
+
+ switch (purpose) {
+ case DIR_PURPOSE_FETCH_CONSENSUS:
+ /* resource is optional. If present, it's a flavor name */
+ tor_assert(!payload);
+ httpcommand = "GET";
+ url = directory_get_consensus_url(resource);
+ log_info(LD_DIR, "Downloading consensus from %s using %s",
+ hoststring, url);
+ break;
+ case DIR_PURPOSE_FETCH_CERTIFICATE:
+ tor_assert(resource);
+ tor_assert(!payload);
+ httpcommand = "GET";
+ tor_asprintf(&url, "/tor/keys/%s", resource);
+ break;
+ case DIR_PURPOSE_FETCH_STATUS_VOTE:
+ tor_assert(resource);
+ tor_assert(!payload);
+ httpcommand = "GET";
+ tor_asprintf(&url, "/tor/status-vote/next/%s.z", resource);
+ break;
+ case DIR_PURPOSE_FETCH_DETACHED_SIGNATURES:
+ tor_assert(!resource);
+ tor_assert(!payload);
+ httpcommand = "GET";
+ url = tor_strdup("/tor/status-vote/next/consensus-signatures.z");
+ break;
+ case DIR_PURPOSE_FETCH_SERVERDESC:
+ tor_assert(resource);
+ httpcommand = "GET";
+ tor_asprintf(&url, "/tor/server/%s", resource);
+ break;
+ case DIR_PURPOSE_FETCH_EXTRAINFO:
+ tor_assert(resource);
+ httpcommand = "GET";
+ tor_asprintf(&url, "/tor/extra/%s", resource);
+ break;
+ case DIR_PURPOSE_FETCH_MICRODESC:
+ tor_assert(resource);
+ httpcommand = "GET";
+ tor_asprintf(&url, "/tor/micro/%s", resource);
+ break;
+ case DIR_PURPOSE_UPLOAD_DIR: {
+ const char *why = router_get_descriptor_gen_reason();
+ tor_assert(!resource);
+ tor_assert(payload);
+ httpcommand = "POST";
+ url = tor_strdup("/tor/");
+ if (!why) {
+ why = "for no reason at all";
+ }
+ smartlist_add_asprintf(headers, "X-Desc-Gen-Reason: %s\r\n", why);
+ break;
+ }
+ case DIR_PURPOSE_UPLOAD_VOTE:
+ tor_assert(!resource);
+ tor_assert(payload);
+ httpcommand = "POST";
+ url = tor_strdup("/tor/post/vote");
+ break;
+ case DIR_PURPOSE_UPLOAD_SIGNATURES:
+ tor_assert(!resource);
+ tor_assert(payload);
+ httpcommand = "POST";
+ url = tor_strdup("/tor/post/consensus-signature");
+ break;
+ case DIR_PURPOSE_FETCH_RENDDESC_V2:
+ tor_assert(resource);
+ tor_assert(strlen(resource) <= REND_DESC_ID_V2_LEN_BASE32);
+ tor_assert(!payload);
+ httpcommand = "GET";
+ tor_asprintf(&url, "/tor/rendezvous2/%s", resource);
+ break;
+ case DIR_PURPOSE_FETCH_HSDESC:
+ tor_assert(resource);
+ tor_assert(strlen(resource) <= ED25519_BASE64_LEN);
+ tor_assert(!payload);
+ httpcommand = "GET";
+ tor_asprintf(&url, "/tor/hs/3/%s", resource);
+ break;
+ case DIR_PURPOSE_UPLOAD_RENDDESC_V2:
+ tor_assert(!resource);
+ tor_assert(payload);
+ httpcommand = "POST";
+ url = tor_strdup("/tor/rendezvous2/publish");
+ break;
+ case DIR_PURPOSE_UPLOAD_HSDESC:
+ tor_assert(resource);
+ tor_assert(payload);
+ httpcommand = "POST";
+ tor_asprintf(&url, "/tor/hs/%s/publish", resource);
+ break;
+ default:
+ tor_assert(0);
+ return;
+ }
+
+ /* warn in the non-tunneled case */
+ if (direct && (strlen(proxystring) + strlen(url) >= 4096)) {
+ log_warn(LD_BUG,
+ "Squid does not like URLs longer than 4095 bytes, and this "
+ "one is %d bytes long: %s%s",
+ (int)(strlen(proxystring) + strlen(url)), proxystring, url);
+ }
+
+ tor_snprintf(request, sizeof(request), "%s %s", httpcommand, proxystring);
+
+ request_len = strlen(request);
+ total_request_len += request_len;
+ connection_buf_add(request, request_len, TO_CONN(conn));
+
+ url_len = strlen(url);
+ total_request_len += url_len;
+ connection_buf_add(url, url_len, TO_CONN(conn));
+ tor_free(url);
+
+ if (!strcmp(httpcommand, "POST") || payload) {
+ smartlist_add_asprintf(headers, "Content-Length: %lu\r\n",
+ payload ? (unsigned long)payload_len : 0);
+ }
+
+ {
+ char *header = smartlist_join_strings(headers, "", 0, NULL);
+ tor_snprintf(request, sizeof(request), " HTTP/1.0\r\nHost: %s\r\n%s\r\n",
+ hoststring, header);
+ tor_free(header);
+ }
+
+ request_len = strlen(request);
+ total_request_len += request_len;
+ connection_buf_add(request, request_len, TO_CONN(conn));
+
+ if (payload) {
+ /* then send the payload afterwards too */
+ connection_buf_add(payload, payload_len, TO_CONN(conn));
+ total_request_len += payload_len;
+ }
+
+ SMARTLIST_FOREACH(headers, char *, h, tor_free(h));
+ smartlist_free(headers);
+
+ log_debug(LD_DIR,
+ "Sent request to directory server '%s:%d': "
+ "(purpose: %d, request size: %"TOR_PRIuSZ", "
+ "payload size: %"TOR_PRIuSZ")",
+ conn->base_.address, conn->base_.port,
+ conn->base_.purpose,
+ (total_request_len),
+ (payload ? payload_len : 0));
+}
+
+/** 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
+ * 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(const char *headers, char **url)
+{
+ char *command = NULL;
+ if (parse_http_command(headers, &command, url) < 0) {
+ return -1;
+ }
+ if (strcmpstart(*url, "/tor/")) {
+ char *new_url = NULL;
+ tor_asprintf(&new_url, "/tor%s%s",
+ *url[0] == '/' ? "" : "/",
+ *url);
+ tor_free(*url);
+ *url = new_url;
+ }
+ tor_free(command);
+ return 0;
+}
+
+/** Parse an HTTP request line at the start of a headers string. On failure,
+ * return -1. On success, set *<b>command_out</b> to a copy of the HTTP
+ * command ("get", "post", etc), set *<b>url_out</b> to a copy of the URL, and
+ * return 0. */
+int
+parse_http_command(const char *headers, char **command_out, char **url_out)
+{
+ const char *command, *end_of_command;
+ char *s, *start, *tmp;
+
+ s = (char *)eat_whitespace_no_nl(headers);
+ if (!*s) return -1;
+ command = s;
+ s = (char *)find_whitespace(s); /* get past GET/POST */
+ if (!*s) return -1;
+ end_of_command = s;
+ s = (char *)eat_whitespace_no_nl(s);
+ if (!*s) return -1;
+ start = s; /* this is the URL, 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;
+ }
+ }
+ }
+
+ /* Check if the header is well formed (next sequence
+ * should be HTTP/1.X\r\n). Assumes we're supporting 1.0? */
+ {
+ unsigned minor_ver;
+ char ch;
+ char *e = (char *)eat_whitespace_no_nl(s);
+ if (2 != tor_sscanf(e, "HTTP/1.%u%c", &minor_ver, &ch)) {
+ return -1;
+ }
+ if (ch != '\r')
+ return -1;
+ }
+
+ *url_out = tor_memdup_nulterm(start, s-start);
+ *command_out = tor_memdup_nulterm(command, end_of_command - command);
+ return 0;
+}
+
+/** Return a copy of the first HTTP header in <b>headers</b> whose key is
+ * <b>which</b>. 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. */
+char *
+http_get_header(const char *headers, const char *which)
+{
+ const char *cp = headers;
+ while (cp) {
+ if (!strcasecmpstart(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 <b>headers</b> indicates that a proxy was involved, then rewrite
+ * <b>conn</b>-\>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_addr_t toraddr;
+ if (tor_addr_parse(&toraddr,fwd) == -1 ||
+ tor_addr_is_internal(&toraddr,0)) {
+ log_debug(LD_DIR, "Ignoring local/internal IP %s", escaped(fwd));
+ tor_free(fwd);
+ return;
+ }
+
+ tor_free(conn->address);
+ conn->address = tor_strdup(fwd);
+ tor_free(fwd);
+ }
+}
+
+/** 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,
+ compress_method_t *compression, char **reason)
+{
+ unsigned 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 (tor_sscanf(headers, "HTTP/1.%u %u", &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_new();
+ smartlist_split_string(parsed_headers, headers, "\n",
+ SPLIT_SKIP_SPACE|SPLIT_IGNORE_BLANK, -1);
+ if (reason) {
+ smartlist_t *status_line_elements = smartlist_new();
+ 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 == NULL)
+ *compression = NO_METHOD;
+ else {
+ *compression = compression_method_get_by_name(enc);
+
+ if (*compression == UNKNOWN_METHOD)
+ log_info(LD_HTTP, "Unrecognized content encoding: %s. Trying to deal.",
+ escaped(enc));
+ }
+ }
+ 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
+ * network-status or microdescriptor 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_MICRODESC) {
+ return (!strcmpstart(body,"onion-key"));
+ }
+
+ if (!strcmpstart(body,"router") ||
+ !strcmpstart(body,"network-status"))
+ return 1;
+ for (i=0;i<32;++i) {
+ if (!TOR_ISPRINT(body[i]) && !TOR_ISSPACE(body[i]))
+ return 0;
+ }
+
+ return 1;
+}
+
+/** Called when we've just fetched a bunch of router descriptors in
+ * <b>body</b>. The list <b>which</b>, if present, holds digests for
+ * descriptors we requested: descriptor digests if <b>descriptor_digests</b>
+ * is true, or identity digests otherwise. Parse the descriptors, validate
+ * them, and annotate them as having purpose <b>purpose</b> and as having been
+ * downloaded from <b>source</b>.
+ *
+ * Return the number of routers actually added. */
+static int
+load_downloaded_routers(const char *body, smartlist_t *which,
+ int descriptor_digests,
+ int router_purpose,
+ const char *source)
+{
+ char buf[256];
+ char time_buf[ISO_TIME_LEN+1];
+ int added = 0;
+ int general = router_purpose == ROUTER_PURPOSE_GENERAL;
+ format_iso_time(time_buf, time(NULL));
+ tor_assert(source);
+
+ if (tor_snprintf(buf, sizeof(buf),
+ "@downloaded-at %s\n"
+ "@source %s\n"
+ "%s%s%s", time_buf, escaped(source),
+ !general ? "@purpose " : "",
+ !general ? router_purpose_to_string(router_purpose) : "",
+ !general ? "\n" : "")<0)
+ return added;
+
+ added = router_load_routers_from_string(body, NULL, SAVED_NOWHERE, which,
+ descriptor_digests, buf);
+ if (added && general)
+ control_event_bootstrap(BOOTSTRAP_STATUS_LOADING_DESCRIPTORS,
+ count_loading_descriptors_progress());
+ return added;
+}
+
+static int handle_response_fetch_certificate(dir_connection_t *,
+ const response_handler_args_t *);
+static int handle_response_fetch_status_vote(dir_connection_t *,
+ const response_handler_args_t *);
+static int handle_response_fetch_detached_signatures(dir_connection_t *,
+ const response_handler_args_t *);
+static int handle_response_fetch_desc(dir_connection_t *,
+ const response_handler_args_t *);
+static int handle_response_upload_dir(dir_connection_t *,
+ const response_handler_args_t *);
+static int handle_response_upload_vote(dir_connection_t *,
+ const response_handler_args_t *);
+static int handle_response_upload_signatures(dir_connection_t *,
+ const response_handler_args_t *);
+static int handle_response_fetch_renddesc_v2(dir_connection_t *,
+ const response_handler_args_t *);
+static int handle_response_upload_renddesc_v2(dir_connection_t *,
+ const response_handler_args_t *);
+static int handle_response_upload_hsdesc(dir_connection_t *,
+ const response_handler_args_t *);
+
+static int
+dir_client_decompress_response_body(char **bodyp, size_t *bodylenp,
+ dir_connection_t *conn,
+ compress_method_t compression,
+ int anonymized_connection)
+{
+ int rv = 0;
+ const char *body = *bodyp;
+ size_t body_len = *bodylenp;
+ int allow_partial = (conn->base_.purpose == DIR_PURPOSE_FETCH_SERVERDESC ||
+ conn->base_.purpose == DIR_PURPOSE_FETCH_EXTRAINFO ||
+ conn->base_.purpose == DIR_PURPOSE_FETCH_MICRODESC);
+
+ int plausible = body_is_plausible(body, body_len, conn->base_.purpose);
+
+ if (plausible && compression == NO_METHOD) {
+ return 0;
+ }
+
+ int severity = LOG_DEBUG;
+ char *new_body = NULL;
+ size_t new_len = 0;
+ const char *description1, *description2;
+ int want_to_try_both = 0;
+ int tried_both = 0;
+ compress_method_t guessed = detect_compression_method(body, body_len);
+
+ description1 = compression_method_get_human_name(compression);
+
+ if (BUG(description1 == NULL))
+ description1 = compression_method_get_human_name(UNKNOWN_METHOD);
+
+ if (guessed == UNKNOWN_METHOD && !plausible)
+ description2 = "confusing binary junk";
+ else
+ description2 = compression_method_get_human_name(guessed);
+
+ /* Tell the user if we don't believe what we're told about compression.*/
+ want_to_try_both = (compression == UNKNOWN_METHOD ||
+ guessed != compression);
+ if (want_to_try_both) {
+ severity = LOG_PROTOCOL_WARN;
+ }
+
+ tor_log(severity, LD_HTTP,
+ "HTTP body from server '%s:%d' was labeled as %s, "
+ "%s it seems to be %s.%s",
+ conn->base_.address, conn->base_.port, description1,
+ guessed != compression?"but":"and",
+ description2,
+ (compression>0 && guessed>0 && want_to_try_both)?
+ " Trying both.":"");
+
+ /* Try declared compression first if we can.
+ * tor_compress_supports_method() also returns true for NO_METHOD.
+ * Ensure that the server is not sending us data compressed using a
+ * compression method that is not allowed for anonymous connections. */
+ if (anonymized_connection &&
+ ! allowed_anonymous_connection_compression_method(compression)) {
+ warn_disallowed_anonymous_compression_method(compression);
+ rv = -1;
+ goto done;
+ }
+
+ if (tor_compress_supports_method(compression)) {
+ tor_uncompress(&new_body, &new_len, body, body_len, compression,
+ !allow_partial, LOG_PROTOCOL_WARN);
+ if (new_body) {
+ /* We succeeded with the declared compression method. Great! */
+ rv = 0;
+ goto done;
+ }
+ }
+
+ /* Okay, if that didn't work, and we think that it was compressed
+ * differently, try that. */
+ if (anonymized_connection &&
+ ! allowed_anonymous_connection_compression_method(guessed)) {
+ warn_disallowed_anonymous_compression_method(guessed);
+ rv = -1;
+ goto done;
+ }
+
+ if (tor_compress_supports_method(guessed) &&
+ compression != guessed) {
+ tor_uncompress(&new_body, &new_len, body, body_len, guessed,
+ !allow_partial, LOG_INFO);
+ tried_both = 1;
+ }
+ /* 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 (tried %s%s%s, server '%s:%d').",
+ description1,
+ tried_both?" and ":"",
+ tried_both?description2:"",
+ conn->base_.address, conn->base_.port);
+ rv = -1;
+ goto done;
+ }
+
+ done:
+ if (new_body) {
+ if (rv == 0) {
+ /* success! */
+ tor_free(*bodyp);
+ *bodyp = new_body;
+ *bodylenp = new_len;
+ } else {
+ tor_free(new_body);
+ }
+ }
+
+ return rv;
+}
+
+/** We are a client, and we've finished reading the server's
+ * response. Parse 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 = NULL;
+ char *headers = NULL;
+ char *reason = NULL;
+ size_t body_len = 0;
+ int status_code;
+ time_t date_header = 0;
+ long apparent_skew;
+ compress_method_t compression;
+ int skewed = 0;
+ int rv;
+ int allow_partial = (conn->base_.purpose == DIR_PURPOSE_FETCH_SERVERDESC ||
+ conn->base_.purpose == DIR_PURPOSE_FETCH_EXTRAINFO ||
+ conn->base_.purpose == DIR_PURPOSE_FETCH_MICRODESC);
+ size_t received_bytes;
+ const int anonymized_connection =
+ purpose_needs_anonymity(conn->base_.purpose,
+ conn->router_purpose,
+ conn->requested_resource);
+
+ received_bytes = connection_get_inbuf_len(TO_CONN(conn));
+
+ switch (connection_fetch_from_buf_http(TO_CONN(conn),
+ &headers, MAX_HEADERS_SIZE,
+ &body, &body_len, MAX_DIR_DL_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 */
+ }
+
+ 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);
+
+ rv = -1;
+ goto done;
+ }
+ if (!reason) reason = tor_strdup("[no reason given]");
+
+ tor_log(LOG_DEBUG, LD_DIR,
+ "Received response from directory server '%s:%d': %d %s "
+ "(purpose: %d, response size: %"TOR_PRIuSZ
+#ifdef MEASUREMENTS_21206
+ ", data cells received: %d, data cells sent: %d"
+#endif
+ ", compression: %d)",
+ conn->base_.address, conn->base_.port, status_code,
+ escaped(reason), conn->base_.purpose,
+ (received_bytes),
+#ifdef MEASUREMENTS_21206
+ conn->data_cells_received, conn->data_cells_sent,
+#endif
+ compression);
+
+ if (conn->guard_state) {
+ /* we count the connection as successful once we can read from it. We do
+ * not, however, delay use of the circuit here, since it's just for a
+ * one-hop directory request. */
+ /* XXXXprop271 note that this will not do the right thing for other
+ * waiting circuits that would be triggered by this circuit becoming
+ * complete/usable. But that's ok, I think.
+ */
+ entry_guard_succeeded(&conn->guard_state);
+ circuit_guard_state_free(conn->guard_state);
+ conn->guard_state = NULL;
+ }
+
+ /* 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, conn);
+ 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.)
+ */
+ apparent_skew = conn->base_.timestamp_last_write_allowed - date_header;
+ if (labs(apparent_skew)>ALLOW_DIRECTORY_TIME_SKEW) {
+ int trusted = router_digest_is_trusted_dir(conn->identity_digest);
+ clock_skew_warning(TO_CONN(conn), apparent_skew, trusted, LD_HTTP,
+ "directory", "DIRSERV");
+ skewed = 1; /* don't check the recommended-versions line */
+ } else {
+ log_debug(LD_HTTP, "Time on received directory is within tolerance; "
+ "we are %ld seconds skewed. (That's okay.)", apparent_skew);
+ }
+ }
+ (void) skewed; /* skewed isn't used yet. */
+
+ if (status_code == 503) {
+ routerstatus_t *rs;
+ dir_server_t *ds;
+ const char *id_digest = conn->identity_digest;
+ 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);
+ time_t now = approx_time();
+ if ((rs = router_get_mutable_consensus_status_by_id(id_digest)))
+ rs->last_dir_503_at = now;
+ if ((ds = router_get_fallback_dirserver_by_digest(id_digest)))
+ ds->fake_status.last_dir_503_at = now;
+
+ rv = -1;
+ goto done;
+ }
+
+ if (dir_client_decompress_response_body(&body, &body_len,
+ conn, compression, anonymized_connection) < 0) {
+ rv = -1;
+ goto done;
+ }
+
+ response_handler_args_t args;
+ memset(&args, 0, sizeof(args));
+ args.status_code = status_code;
+ args.reason = reason;
+ args.body = body;
+ args.body_len = body_len;
+ args.headers = headers;
+
+ switch (conn->base_.purpose) {
+ case DIR_PURPOSE_FETCH_CONSENSUS:
+ rv = handle_response_fetch_consensus(conn, &args);
+ break;
+ case DIR_PURPOSE_FETCH_CERTIFICATE:
+ rv = handle_response_fetch_certificate(conn, &args);
+ break;
+ case DIR_PURPOSE_FETCH_STATUS_VOTE:
+ rv = handle_response_fetch_status_vote(conn, &args);
+ break;
+ case DIR_PURPOSE_FETCH_DETACHED_SIGNATURES:
+ rv = handle_response_fetch_detached_signatures(conn, &args);
+ break;
+ case DIR_PURPOSE_FETCH_SERVERDESC:
+ case DIR_PURPOSE_FETCH_EXTRAINFO:
+ rv = handle_response_fetch_desc(conn, &args);
+ break;
+ case DIR_PURPOSE_FETCH_MICRODESC:
+ rv = handle_response_fetch_microdesc(conn, &args);
+ break;
+ case DIR_PURPOSE_FETCH_RENDDESC_V2:
+ rv = handle_response_fetch_renddesc_v2(conn, &args);
+ break;
+ case DIR_PURPOSE_UPLOAD_DIR:
+ rv = handle_response_upload_dir(conn, &args);
+ break;
+ case DIR_PURPOSE_UPLOAD_SIGNATURES:
+ rv = handle_response_upload_signatures(conn, &args);
+ break;
+ case DIR_PURPOSE_UPLOAD_VOTE:
+ rv = handle_response_upload_vote(conn, &args);
+ break;
+ case DIR_PURPOSE_UPLOAD_RENDDESC_V2:
+ rv = handle_response_upload_renddesc_v2(conn, &args);
+ break;
+ case DIR_PURPOSE_UPLOAD_HSDESC:
+ rv = handle_response_upload_hsdesc(conn, &args);
+ break;
+ case DIR_PURPOSE_FETCH_HSDESC:
+ rv = handle_response_fetch_hsdesc_v3(conn, &args);
+ break;
+ default:
+ tor_assert_nonfatal_unreached();
+ rv = -1;
+ break;
+ }
+
+ done:
+ tor_free(body);
+ tor_free(headers);
+ tor_free(reason);
+ return rv;
+}
+
+/**
+ * Handler function: processes a response to a request for a networkstatus
+ * consensus document by checking the consensus, storing it, and marking
+ * router requests as reachable.
+ **/
+STATIC int
+handle_response_fetch_consensus(dir_connection_t *conn,
+ const response_handler_args_t *args)
+{
+ tor_assert(conn->base_.purpose == DIR_PURPOSE_FETCH_CONSENSUS);
+ const int status_code = args->status_code;
+ const char *body = args->body;
+ const size_t body_len = args->body_len;
+ const char *reason = args->reason;
+ const time_t now = approx_time();
+
+ const char *consensus;
+ char *new_consensus = NULL;
+ const char *sourcename;
+
+ int r;
+ const char *flavname = conn->requested_resource;
+ if (status_code != 200) {
+ int severity = (status_code == 304) ? LOG_INFO : LOG_WARN;
+ tor_log(severity, LD_DIR,
+ "Received http status code %d (%s) from server "
+ "'%s:%d' while fetching consensus directory.",
+ status_code, escaped(reason), conn->base_.address,
+ conn->base_.port);
+ networkstatus_consensus_download_failed(status_code, flavname);
+ return -1;
+ }
+
+ if (looks_like_a_consensus_diff(body, body_len)) {
+ /* First find our previous consensus. Maybe it's in ram, maybe not. */
+ cached_dir_t *cd = dirserv_get_consensus(flavname);
+ const char *consensus_body;
+ char *owned_consensus = NULL;
+ if (cd) {
+ consensus_body = cd->dir;
+ } else {
+ owned_consensus = networkstatus_read_cached_consensus(flavname);
+ consensus_body = owned_consensus;
+ }
+ if (!consensus_body) {
+ log_warn(LD_DIR, "Received a consensus diff, but we can't find "
+ "any %s-flavored consensus in our current cache.",flavname);
+ networkstatus_consensus_download_failed(0, flavname);
+ // XXXX if this happens too much, see below
+ return -1;
+ }
+
+ new_consensus = consensus_diff_apply(consensus_body, body);
+ tor_free(owned_consensus);
+ if (new_consensus == NULL) {
+ log_warn(LD_DIR, "Could not apply consensus diff received from server "
+ "'%s:%d'", conn->base_.address, conn->base_.port);
+ // XXXX If this happens too many times, we should maybe not use
+ // XXXX this directory for diffs any more?
+ networkstatus_consensus_download_failed(0, flavname);
+ return -1;
+ }
+ log_info(LD_DIR, "Applied consensus diff (size %d) from server "
+ "'%s:%d', resulting in a new consensus document (size %d).",
+ (int)body_len, conn->base_.address, conn->base_.port,
+ (int)strlen(new_consensus));
+ consensus = new_consensus;
+ sourcename = "generated based on a diff";
+ } else {
+ log_info(LD_DIR,"Received consensus directory (body size %d) from server "
+ "'%s:%d'", (int)body_len, conn->base_.address, conn->base_.port);
+ consensus = body;
+ sourcename = "downloaded";
+ }
+
+ if ((r=networkstatus_set_current_consensus(consensus, flavname, 0,
+ conn->identity_digest))<0) {
+ log_fn(r<-1?LOG_WARN:LOG_INFO, LD_DIR,
+ "Unable to load %s consensus directory %s from "
+ "server '%s:%d'. I'll try again soon.",
+ flavname, sourcename, conn->base_.address, conn->base_.port);
+ networkstatus_consensus_download_failed(0, flavname);
+ tor_free(new_consensus);
+ return -1;
+ }
+
+ /* If we launched other fetches for this consensus, cancel them. */
+ connection_dir_close_consensus_fetches(conn, flavname);
+
+ /* update the list of routers and directory guards */
+ routers_update_all_from_networkstatus(now, 3);
+ update_microdescs_from_networkstatus(now);
+ directory_info_has_arrived(now, 0, 0);
+
+ if (authdir_mode_v3(get_options())) {
+ sr_act_post_consensus(
+ networkstatus_get_latest_consensus_by_flavor(FLAV_NS));
+ }
+ log_info(LD_DIR, "Successfully loaded consensus.");
+
+ tor_free(new_consensus);
+ return 0;
+}
+
+/**
+ * Handler function: processes a response to a request for one or more
+ * authority certificates
+ **/
+static int
+handle_response_fetch_certificate(dir_connection_t *conn,
+ const response_handler_args_t *args)
+{
+ tor_assert(conn->base_.purpose == DIR_PURPOSE_FETCH_CERTIFICATE);
+ const int status_code = args->status_code;
+ const char *reason = args->reason;
+ const char *body = args->body;
+ const size_t body_len = args->body_len;
+
+ if (status_code != 200) {
+ log_warn(LD_DIR,
+ "Received http status code %d (%s) from server "
+ "'%s:%d' while fetching \"/tor/keys/%s\".",
+ status_code, escaped(reason), conn->base_.address,
+ conn->base_.port, conn->requested_resource);
+ connection_dir_download_cert_failed(conn, status_code);
+ return -1;
+ }
+ log_info(LD_DIR,"Received authority certificates (body size %d) from "
+ "server '%s:%d'",
+ (int)body_len, conn->base_.address, conn->base_.port);
+
+ /*
+ * Tell trusted_dirs_load_certs_from_string() whether it was by fp
+ * or fp-sk pair.
+ */
+ int src_code = -1;
+ if (!strcmpstart(conn->requested_resource, "fp/")) {
+ src_code = TRUSTED_DIRS_CERTS_SRC_DL_BY_ID_DIGEST;
+ } else if (!strcmpstart(conn->requested_resource, "fp-sk/")) {
+ src_code = TRUSTED_DIRS_CERTS_SRC_DL_BY_ID_SK_DIGEST;
+ }
+
+ if (src_code != -1) {
+ if (trusted_dirs_load_certs_from_string(body, src_code, 1,
+ conn->identity_digest)<0) {
+ log_warn(LD_DIR, "Unable to parse fetched certificates");
+ /* if we fetched more than one and only some failed, the successful
+ * ones got flushed to disk so it's safe to call this on them */
+ connection_dir_download_cert_failed(conn, status_code);
+ } else {
+ time_t now = approx_time();
+ directory_info_has_arrived(now, 0, 0);
+ log_info(LD_DIR, "Successfully loaded certificates from fetch.");
+ }
+ } else {
+ log_warn(LD_DIR,
+ "Couldn't figure out what to do with fetched certificates for "
+ "unknown resource %s",
+ conn->requested_resource);
+ connection_dir_download_cert_failed(conn, status_code);
+ }
+ return 0;
+}
+
+/**
+ * Handler function: processes a response to a request for an authority's
+ * current networkstatus vote.
+ **/
+static int
+handle_response_fetch_status_vote(dir_connection_t *conn,
+ const response_handler_args_t *args)
+{
+ tor_assert(conn->base_.purpose == DIR_PURPOSE_FETCH_STATUS_VOTE);
+ const int status_code = args->status_code;
+ const char *reason = args->reason;
+ const char *body = args->body;
+ const size_t body_len = args->body_len;
+
+ const char *msg;
+ int st;
+ log_info(LD_DIR,"Got votes (body 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-vote/next/%s.z\".",
+ status_code, escaped(reason), conn->base_.address,
+ conn->base_.port, conn->requested_resource);
+ return -1;
+ }
+ dirvote_add_vote(body, &msg, &st);
+ if (st > 299) {
+ log_warn(LD_DIR, "Error adding retrieved vote: %s", msg);
+ } else {
+ log_info(LD_DIR, "Added vote(s) successfully [msg: %s]", msg);
+ }
+
+ return 0;
+}
+
+/**
+ * Handler function: processes a response to a request for the signatures
+ * that an authority knows about on a given consensus.
+ **/
+static int
+handle_response_fetch_detached_signatures(dir_connection_t *conn,
+ const response_handler_args_t *args)
+{
+ tor_assert(conn->base_.purpose == DIR_PURPOSE_FETCH_DETACHED_SIGNATURES);
+ const int status_code = args->status_code;
+ const char *reason = args->reason;
+ const char *body = args->body;
+ const size_t body_len = args->body_len;
+
+ const char *msg = NULL;
+ log_info(LD_DIR,"Got detached signatures (body 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-vote/next/consensus-signatures.z\".",
+ status_code, escaped(reason), conn->base_.address,
+ conn->base_.port);
+ return -1;
+ }
+ if (dirvote_add_signatures(body, conn->base_.address, &msg)<0) {
+ log_warn(LD_DIR, "Problem adding detached signatures from %s:%d: %s",
+ conn->base_.address, conn->base_.port, msg?msg:"???");
+ }
+
+ return 0;
+}
+
+/**
+ * Handler function: processes a response to a request for a group of server
+ * descriptors or an extrainfo documents.
+ **/
+static int
+handle_response_fetch_desc(dir_connection_t *conn,
+ const response_handler_args_t *args)
+{
+ tor_assert(conn->base_.purpose == DIR_PURPOSE_FETCH_SERVERDESC ||
+ conn->base_.purpose == DIR_PURPOSE_FETCH_EXTRAINFO);
+ const int status_code = args->status_code;
+ const char *reason = args->reason;
+ const char *body = args->body;
+ const size_t body_len = args->body_len;
+
+ int was_ei = conn->base_.purpose == DIR_PURPOSE_FETCH_EXTRAINFO;
+ smartlist_t *which = NULL;
+ int n_asked_for = 0;
+ int descriptor_digests = conn->requested_resource &&
+ !strcmpstart(conn->requested_resource,"d/");
+ log_info(LD_DIR,"Received %s (body size %d) from server '%s:%d'",
+ was_ei ? "extra server info" : "server info",
+ (int)body_len, conn->base_.address, conn->base_.port);
+ if (conn->requested_resource &&
+ (!strcmpstart(conn->requested_resource,"d/") ||
+ !strcmpstart(conn->requested_resource,"fp/"))) {
+ which = smartlist_new();
+ dir_split_resource_into_fingerprints(conn->requested_resource +
+ (descriptor_digests ? 2 : 3),
+ which, NULL, 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,
+ conn->router_purpose,
+ was_ei, descriptor_digests);
+ SMARTLIST_FOREACH(which, char *, cp, tor_free(cp));
+ smartlist_free(which);
+ }
+ return dir_okay ? 0 : -1;
+ }
+ /* Learn the routers, assuming we requested by fingerprint or "all"
+ * or "authority".
+ *
+ * We use "authority" to fetch our own descriptor for
+ * testing, and to fetch bridge descriptors for bootstrapping. Ignore
+ * the output of "authority" requests unless we are using bridges,
+ * since otherwise they'll be the response from reachability tests,
+ * and we don't really want to add that to our routerlist. */
+ if (which || (conn->requested_resource &&
+ (!strcmpstart(conn->requested_resource, "all") ||
+ (!strcmpstart(conn->requested_resource, "authority") &&
+ get_options()->UseBridges)))) {
+ /* as we learn from them, we remove them from 'which' */
+ if (was_ei) {
+ router_load_extrainfo_from_string(body, NULL, SAVED_NOWHERE, which,
+ descriptor_digests);
+ } else {
+ //router_load_routers_from_string(body, NULL, SAVED_NOWHERE, which,
+ // descriptor_digests, conn->router_purpose);
+ if (load_downloaded_routers(body, which, descriptor_digests,
+ conn->router_purpose,
+ conn->base_.address)) {
+ time_t now = approx_time();
+ directory_info_has_arrived(now, 0, 1);
+ }
+ }
+ }
+ if (which) { /* mark remaining ones as failed */
+ log_info(LD_DIR, "Received %d/%d %s requested from %s:%d",
+ n_asked_for-smartlist_len(which), n_asked_for,
+ was_ei ? "extra-info documents" : "router descriptors",
+ conn->base_.address, (int)conn->base_.port);
+ if (smartlist_len(which)) {
+ dir_routerdesc_download_failed(which, status_code,
+ conn->router_purpose,
+ was_ei, descriptor_digests);
+ }
+ SMARTLIST_FOREACH(which, char *, cp, tor_free(cp));
+ smartlist_free(which);
+ }
+ if (directory_conn_is_self_reachability_test(conn))
+ router_dirport_found_reachable();
+
+ return 0;
+}
+
+/**
+ * Handler function: processes a response to a request for a group of
+ * microdescriptors
+ **/
+STATIC int
+handle_response_fetch_microdesc(dir_connection_t *conn,
+ const response_handler_args_t *args)
+{
+ tor_assert(conn->base_.purpose == DIR_PURPOSE_FETCH_MICRODESC);
+ const int status_code = args->status_code;
+ const char *reason = args->reason;
+ const char *body = args->body;
+ const size_t body_len = args->body_len;
+
+ smartlist_t *which = NULL;
+ log_info(LD_DIR,"Received answer to microdescriptor request (status %d, "
+ "body size %d) from server '%s:%d'",
+ status_code, (int)body_len, conn->base_.address,
+ conn->base_.port);
+ tor_assert(conn->requested_resource &&
+ !strcmpstart(conn->requested_resource, "d/"));
+ tor_assert_nonfatal(!tor_mem_is_zero(conn->identity_digest, DIGEST_LEN));
+ which = smartlist_new();
+ dir_split_resource_into_fingerprints(conn->requested_resource+2,
+ which, NULL,
+ DSR_DIGEST256|DSR_BASE64);
+ if (status_code != 200) {
+ log_info(LD_DIR, "Received status code %d (%s) from server "
+ "'%s:%d' while fetching \"/tor/micro/%s\". I'll try again "
+ "soon.",
+ status_code, escaped(reason), conn->base_.address,
+ (int)conn->base_.port, conn->requested_resource);
+ dir_microdesc_download_failed(which, status_code, conn->identity_digest);
+ SMARTLIST_FOREACH(which, char *, cp, tor_free(cp));
+ smartlist_free(which);
+ return 0;
+ } else {
+ smartlist_t *mds;
+ time_t now = approx_time();
+ mds = microdescs_add_to_cache(get_microdesc_cache(),
+ body, body+body_len, SAVED_NOWHERE, 0,
+ now, which);
+ if (smartlist_len(which)) {
+ /* Mark remaining ones as failed. */
+ dir_microdesc_download_failed(which, status_code, conn->identity_digest);
+ }
+ if (mds && smartlist_len(mds)) {
+ control_event_bootstrap(BOOTSTRAP_STATUS_LOADING_DESCRIPTORS,
+ count_loading_descriptors_progress());
+ directory_info_has_arrived(now, 0, 1);
+ }
+ SMARTLIST_FOREACH(which, char *, cp, tor_free(cp));
+ smartlist_free(which);
+ smartlist_free(mds);
+ }
+
+ return 0;
+}
+
+/**
+ * Handler function: processes a response to a POST request to upload our
+ * router descriptor.
+ **/
+static int
+handle_response_upload_dir(dir_connection_t *conn,
+ const response_handler_args_t *args)
+{
+ tor_assert(conn->base_.purpose == DIR_PURPOSE_UPLOAD_DIR);
+ const int status_code = args->status_code;
+ const char *reason = args->reason;
+ const char *headers = args->headers;
+
+ switch (status_code) {
+ case 200: {
+ dir_server_t *ds =
+ router_get_trusteddirserver_by_digest(conn->identity_digest);
+ char *rejected_hdr = http_get_header(headers,
+ "X-Descriptor-Not-New: ");
+ if (rejected_hdr) {
+ if (!strcmp(rejected_hdr, "Yes")) {
+ log_info(LD_GENERAL,
+ "Authority '%s' declined our descriptor (not new)",
+ ds->nickname);
+ /* XXXX use this information; be sure to upload next one
+ * sooner. -NM */
+ /* XXXX++ On further thought, the task above implies that we're
+ * basing our regenerate-descriptor time on when we uploaded the
+ * last descriptor, not on the published time of the last
+ * descriptor. If those are different, that's a bad thing to
+ * do. -NM */
+ }
+ tor_free(rejected_hdr);
+ }
+ 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;
+ if (directories_have_accepted_server_descriptor())
+ 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;
+ default:
+ log_warn(LD_GENERAL,
+ "HTTP status %d (%s) was unexpected while uploading "
+ "descriptor to server '%s:%d'. Possibly the server is "
+ "misconfigured?",
+ 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. */
+
+ return 0;
+}
+
+/**
+ * Handler function: processes a response to POST request to upload our
+ * own networkstatus vote.
+ **/
+static int
+handle_response_upload_vote(dir_connection_t *conn,
+ const response_handler_args_t *args)
+{
+ tor_assert(conn->base_.purpose == DIR_PURPOSE_UPLOAD_VOTE);
+ const int status_code = args->status_code;
+ const char *reason = args->reason;
+
+ switch (status_code) {
+ case 200: {
+ log_notice(LD_DIR,"Uploaded a vote to dirserver %s:%d",
+ conn->base_.address, conn->base_.port);
+ }
+ break;
+ case 400:
+ log_warn(LD_DIR,"http status 400 (%s) response after uploading "
+ "vote to dirserver '%s:%d'. Please correct.",
+ escaped(reason), conn->base_.address, conn->base_.port);
+ break;
+ default:
+ log_warn(LD_GENERAL,
+ "HTTP status %d (%s) was unexpected while uploading "
+ "vote 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. */
+ return 0;
+}
+
+/**
+ * Handler function: processes a response to POST request to upload our
+ * view of the signatures on the current consensus.
+ **/
+static int
+handle_response_upload_signatures(dir_connection_t *conn,
+ const response_handler_args_t *args)
+{
+ tor_assert(conn->base_.purpose == DIR_PURPOSE_UPLOAD_SIGNATURES);
+ const int status_code = args->status_code;
+ const char *reason = args->reason;
+
+ switch (status_code) {
+ case 200: {
+ log_notice(LD_DIR,"Uploaded signature(s) to dirserver %s:%d",
+ conn->base_.address, conn->base_.port);
+ }
+ break;
+ case 400:
+ log_warn(LD_DIR,"http status 400 (%s) response after uploading "
+ "signatures to dirserver '%s:%d'. Please correct.",
+ escaped(reason), conn->base_.address, conn->base_.port);
+ break;
+ default:
+ log_warn(LD_GENERAL,
+ "HTTP status %d (%s) was unexpected while uploading "
+ "signatures 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. */
+
+ return 0;
+}
+
+/**
+ * Handler function: processes a response to a request for a v3 hidden service
+ * descriptor.
+ **/
+STATIC int
+handle_response_fetch_hsdesc_v3(dir_connection_t *conn,
+ const response_handler_args_t *args)
+{
+ const int status_code = args->status_code;
+ const char *reason = args->reason;
+ const char *body = args->body;
+ const size_t body_len = args->body_len;
+
+ tor_assert(conn->hs_ident);
+
+ log_info(LD_REND,"Received v3 hsdesc (body size %d, status %d (%s))",
+ (int)body_len, status_code, escaped(reason));
+
+ switch (status_code) {
+ case 200:
+ /* We got something: Try storing it in the cache. */
+ if (hs_cache_store_as_client(body, &conn->hs_ident->identity_pk) < 0) {
+ log_warn(LD_REND, "Failed to store hidden service descriptor");
+ /* Fire control port FAILED event. */
+ hs_control_desc_event_failed(conn->hs_ident, conn->identity_digest,
+ "BAD_DESC");
+ hs_control_desc_event_content(conn->hs_ident, conn->identity_digest,
+ NULL);
+ } else {
+ log_info(LD_REND, "Stored hidden service descriptor successfully.");
+ TO_CONN(conn)->purpose = DIR_PURPOSE_HAS_FETCHED_HSDESC;
+ hs_client_desc_has_arrived(conn->hs_ident);
+ /* Fire control port RECEIVED event. */
+ hs_control_desc_event_received(conn->hs_ident, conn->identity_digest);
+ hs_control_desc_event_content(conn->hs_ident, conn->identity_digest,
+ body);
+ }
+ break;
+ case 404:
+ /* Not there. We'll retry when connection_about_to_close_connection()
+ * tries to clean this conn up. */
+ log_info(LD_REND, "Fetching hidden service v3 descriptor not found: "
+ "Retrying at another directory.");
+ /* Fire control port FAILED event. */
+ hs_control_desc_event_failed(conn->hs_ident, conn->identity_digest,
+ "NOT_FOUND");
+ hs_control_desc_event_content(conn->hs_ident, conn->identity_digest,
+ NULL);
+ break;
+ case 400:
+ log_warn(LD_REND, "Fetching v3 hidden service descriptor failed: "
+ "http status 400 (%s). Dirserver didn't like our "
+ "query? Retrying at another directory.",
+ escaped(reason));
+ /* Fire control port FAILED event. */
+ hs_control_desc_event_failed(conn->hs_ident, conn->identity_digest,
+ "QUERY_REJECTED");
+ hs_control_desc_event_content(conn->hs_ident, conn->identity_digest,
+ NULL);
+ break;
+ default:
+ log_warn(LD_REND, "Fetching v3 hidden service descriptor failed: "
+ "http status %d (%s) response unexpected from HSDir server "
+ "'%s:%d'. Retrying at another directory.",
+ status_code, escaped(reason), TO_CONN(conn)->address,
+ TO_CONN(conn)->port);
+ /* Fire control port FAILED event. */
+ hs_control_desc_event_failed(conn->hs_ident, conn->identity_digest,
+ "UNEXPECTED");
+ hs_control_desc_event_content(conn->hs_ident, conn->identity_digest,
+ NULL);
+ break;
+ }
+
+ return 0;
+}
+
+/**
+ * Handler function: processes a response to a request for a v2 hidden service
+ * descriptor.
+ **/
+static int
+handle_response_fetch_renddesc_v2(dir_connection_t *conn,
+ const response_handler_args_t *args)
+{
+ tor_assert(conn->base_.purpose == DIR_PURPOSE_FETCH_RENDDESC_V2);
+ const int status_code = args->status_code;
+ const char *reason = args->reason;
+ const char *body = args->body;
+ const size_t body_len = args->body_len;
+
+#define SEND_HS_DESC_FAILED_EVENT(reason) \
+ (control_event_hsv2_descriptor_failed(conn->rend_data, \
+ conn->identity_digest, \
+ reason))
+#define SEND_HS_DESC_FAILED_CONTENT() \
+ (control_event_hs_descriptor_content( \
+ rend_data_get_address(conn->rend_data), \
+ conn->requested_resource, \
+ conn->identity_digest, \
+ NULL))
+
+ tor_assert(conn->rend_data);
+ log_info(LD_REND,"Received rendezvous descriptor (body size %d, status %d "
+ "(%s))",
+ (int)body_len, status_code, escaped(reason));
+ switch (status_code) {
+ case 200:
+ {
+ rend_cache_entry_t *entry = NULL;
+
+ if (rend_cache_store_v2_desc_as_client(body,
+ conn->requested_resource,
+ conn->rend_data, &entry) < 0) {
+ log_warn(LD_REND,"Fetching v2 rendezvous descriptor failed. "
+ "Retrying at another directory.");
+ /* We'll retry when connection_about_to_close_connection()
+ * cleans this dir conn up. */
+ SEND_HS_DESC_FAILED_EVENT("BAD_DESC");
+ SEND_HS_DESC_FAILED_CONTENT();
+ } else {
+ char service_id[REND_SERVICE_ID_LEN_BASE32 + 1];
+ /* Should never be NULL here if we found the descriptor. */
+ tor_assert(entry);
+ rend_get_service_id(entry->parsed->pk, service_id);
+
+ /* success. notify pending connections about this. */
+ log_info(LD_REND, "Successfully fetched v2 rendezvous "
+ "descriptor.");
+ control_event_hsv2_descriptor_received(service_id,
+ conn->rend_data,
+ conn->identity_digest);
+ control_event_hs_descriptor_content(service_id,
+ conn->requested_resource,
+ conn->identity_digest,
+ body);
+ conn->base_.purpose = DIR_PURPOSE_HAS_FETCHED_RENDDESC_V2;
+ rend_client_desc_trynow(service_id);
+ memwipe(service_id, 0, sizeof(service_id));
+ }
+ break;
+ }
+ case 404:
+ /* Not there. We'll retry when
+ * connection_about_to_close_connection() cleans this conn up. */
+ log_info(LD_REND,"Fetching v2 rendezvous descriptor failed: "
+ "Retrying at another directory.");
+ SEND_HS_DESC_FAILED_EVENT("NOT_FOUND");
+ SEND_HS_DESC_FAILED_CONTENT();
+ break;
+ case 400:
+ log_warn(LD_REND, "Fetching v2 rendezvous descriptor failed: "
+ "http status 400 (%s). Dirserver didn't like our "
+ "v2 rendezvous query? Retrying at another directory.",
+ escaped(reason));
+ SEND_HS_DESC_FAILED_EVENT("QUERY_REJECTED");
+ SEND_HS_DESC_FAILED_CONTENT();
+ break;
+ default:
+ log_warn(LD_REND, "Fetching v2 rendezvous descriptor failed: "
+ "http status %d (%s) response unexpected while "
+ "fetching v2 hidden service descriptor (server '%s:%d'). "
+ "Retrying at another directory.",
+ status_code, escaped(reason), conn->base_.address,
+ conn->base_.port);
+ SEND_HS_DESC_FAILED_EVENT("UNEXPECTED");
+ SEND_HS_DESC_FAILED_CONTENT();
+ break;
+ }
+
+ return 0;
+}
+
+/**
+ * Handler function: processes a response to a POST request to upload a v2
+ * hidden service descriptor.
+ **/
+static int
+handle_response_upload_renddesc_v2(dir_connection_t *conn,
+ const response_handler_args_t *args)
+{
+ tor_assert(conn->base_.purpose == DIR_PURPOSE_UPLOAD_RENDDESC_V2);
+ const int status_code = args->status_code;
+ const char *reason = args->reason;
+
+#define SEND_HS_DESC_UPLOAD_FAILED_EVENT(reason) \
+ (control_event_hs_descriptor_upload_failed( \
+ conn->identity_digest, \
+ rend_data_get_address(conn->rend_data), \
+ reason))
+
+ log_info(LD_REND,"Uploaded rendezvous descriptor (status %d "
+ "(%s))",
+ status_code, escaped(reason));
+ /* Without the rend data, we'll have a problem identifying what has been
+ * uploaded for which service. */
+ tor_assert(conn->rend_data);
+ switch (status_code) {
+ case 200:
+ log_info(LD_REND,
+ "Uploading rendezvous descriptor: finished with status "
+ "200 (%s)", escaped(reason));
+ control_event_hs_descriptor_uploaded(conn->identity_digest,
+ rend_data_get_address(conn->rend_data));
+ rend_service_desc_has_uploaded(conn->rend_data);
+ 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);
+ SEND_HS_DESC_UPLOAD_FAILED_EVENT("UPLOAD_REJECTED");
+ 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);
+ SEND_HS_DESC_UPLOAD_FAILED_EVENT("UNEXPECTED");
+ break;
+ }
+
+ return 0;
+}
+
+/**
+ * Handler function: processes a response to a POST request to upload an
+ * hidden service descriptor.
+ **/
+static int
+handle_response_upload_hsdesc(dir_connection_t *conn,
+ const response_handler_args_t *args)
+{
+ const int status_code = args->status_code;
+ const char *reason = args->reason;
+
+ tor_assert(conn);
+ tor_assert(conn->base_.purpose == DIR_PURPOSE_UPLOAD_HSDESC);
+
+ log_info(LD_REND, "Uploaded hidden service descriptor (status %d "
+ "(%s))",
+ status_code, escaped(reason));
+ /* For this directory response, it MUST have an hidden service identifier on
+ * this connection. */
+ tor_assert(conn->hs_ident);
+ switch (status_code) {
+ case 200:
+ log_info(LD_REND, "Uploading hidden service descriptor: "
+ "finished with status 200 (%s)", escaped(reason));
+ hs_control_desc_event_uploaded(conn->hs_ident, conn->identity_digest);
+ break;
+ case 400:
+ log_fn(LOG_PROTOCOL_WARN, LD_REND,
+ "Uploading hidden service descriptor: http "
+ "status 400 (%s) response from dirserver "
+ "'%s:%d'. Malformed hidden service descriptor?",
+ escaped(reason), conn->base_.address, conn->base_.port);
+ hs_control_desc_event_failed(conn->hs_ident, conn->identity_digest,
+ "UPLOAD_REJECTED");
+ break;
+ default:
+ log_warn(LD_REND, "Uploading hidden service descriptor: http "
+ "status %d (%s) response unexpected (server "
+ "'%s:%d').",
+ status_code, escaped(reason), conn->base_.address,
+ conn->base_.port);
+ hs_control_desc_event_failed(conn->hs_ident, conn->identity_digest,
+ "UNEXPECTED");
+ break;
+ }
+
+ 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. [state=%d] Closing.",
+ conn->base_.state);
+ 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))
+
+#define MAX_VOTE_DL_SIZE (MAX_DIRECTORY_OBJECT_SIZE * 5)
+
+/** 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(dir_connection_t *conn)
+{
+ size_t max_size;
+ 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;
+ }
+
+ max_size =
+ (TO_CONN(conn)->purpose == DIR_PURPOSE_FETCH_STATUS_VOTE) ?
+ MAX_VOTE_DL_SIZE : MAX_DIRECTORY_OBJECT_SIZE;
+
+ if (connection_get_inbuf_len(TO_CONN(conn)) > max_size) {
+ log_warn(LD_HTTP,
+ "Too much data received from directory connection (%s): "
+ "denial of service attempt, or you need to upgrade?",
+ conn->base_.address);
+ 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;
+}
+
+/** We are closing a dir connection: If <b>dir_conn</b> is a dir connection
+ * that tried to fetch an HS descriptor, check if it successfully fetched it,
+ * or if we need to try again. */
+static void
+refetch_hsdesc_if_needed(dir_connection_t *dir_conn)
+{
+ connection_t *conn = TO_CONN(dir_conn);
+
+ /* If we were trying to fetch a v2 rend desc and did not succeed, retry as
+ * needed. (If a fetch is successful, the connection state is changed to
+ * DIR_PURPOSE_HAS_FETCHED_RENDDESC_V2 or DIR_PURPOSE_HAS_FETCHED_HSDESC to
+ * mark that refetching is unnecessary.) */
+ if (conn->purpose == DIR_PURPOSE_FETCH_RENDDESC_V2 &&
+ dir_conn->rend_data &&
+ rend_valid_v2_service_id(
+ rend_data_get_address(dir_conn->rend_data))) {
+ rend_client_refetch_v2_renddesc(dir_conn->rend_data);
+ }
+
+ /* Check for v3 rend desc fetch */
+ if (conn->purpose == DIR_PURPOSE_FETCH_HSDESC &&
+ dir_conn->hs_ident &&
+ !ed25519_public_key_is_zero(&dir_conn->hs_ident->identity_pk)) {
+ hs_client_refetch_hsdesc(&dir_conn->hs_ident->identity_pk);
+ }
+}
+
+/** Called when we're about to finally unlink and free a directory connection:
+ * perform necessary accounting and cleanup */
+void
+connection_dir_about_to_close(dir_connection_t *dir_conn)
+{
+ connection_t *conn = TO_CONN(dir_conn);
+
+ if (conn->state < DIR_CONN_STATE_CLIENT_FINISHED) {
+ /* It's a directory connection and connecting or fetching
+ * failed: forget about this router, and maybe try again. */
+ connection_dir_request_failed(dir_conn);
+ }
+
+ refetch_hsdesc_if_needed(dir_conn);
+}
+
+/** 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_short_http_response(dir_connection_t *conn, int status,
+ const char *reason_phrase)
+{
+ char *buf = NULL;
+ char *datestring = NULL;
+
+ IF_BUG_ONCE(!reason_phrase) { /* bullet-proofing */
+ reason_phrase = "unspecified";
+ }
+
+ if (server_mode(get_options())) {
+ /* include the Date: header, but only if we're a relay or bridge */
+ char datebuf[RFC1123_TIME_LEN+1];
+ format_rfc1123_time(datebuf, time(NULL));
+ tor_asprintf(&datestring, "Date: %s\r\n", datebuf);
+ }
+
+ tor_asprintf(&buf, "HTTP/1.0 %d %s\r\n%s\r\n",
+ status, reason_phrase, datestring?datestring:"");
+
+ log_debug(LD_DIRSERV,"Wrote status 'HTTP/1.0 %d %s'", status, reason_phrase);
+ connection_buf_add(buf, strlen(buf), TO_CONN(conn));
+
+ tor_free(datestring);
+ tor_free(buf);
+}
+
+/** Write the header for an HTTP/1.0 response onto <b>conn</b>-\>outbuf,
+ * with <b>type</b> as the Content-Type.
+ *
+ * If <b>length</b> is nonnegative, it is the Content-Length.
+ * If <b>encoding</b> is provided, it is the Content-Encoding.
+ * If <b>cache_lifetime</b> 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_impl(dir_connection_t *conn, ssize_t length,
+ const char *type, const char *encoding,
+ const char *extra_headers,
+ long cache_lifetime)
+{
+ char date[RFC1123_TIME_LEN+1];
+ time_t now = time(NULL);
+ buf_t *buf = buf_new_with_capacity(1024);
+
+ tor_assert(conn);
+
+ format_rfc1123_time(date, now);
+
+ buf_add_printf(buf, "HTTP/1.0 200 OK\r\nDate: %s\r\n", date);
+ if (type) {
+ buf_add_printf(buf, "Content-Type: %s\r\n", type);
+ }
+ if (!is_local_addr(&conn->base_.addr)) {
+ /* Don't report the source address for a nearby/private connection.
+ * Otherwise we tend to mis-report in cases where incoming ports are
+ * being forwarded to a Tor server running behind the firewall. */
+ buf_add_printf(buf, X_ADDRESS_HEADER "%s\r\n", conn->base_.address);
+ }
+ if (encoding) {
+ buf_add_printf(buf, "Content-Encoding: %s\r\n", encoding);
+ }
+ if (length >= 0) {
+ buf_add_printf(buf, "Content-Length: %ld\r\n", (long)length);
+ }
+ if (cache_lifetime > 0) {
+ char expbuf[RFC1123_TIME_LEN+1];
+ format_rfc1123_time(expbuf, (time_t)(now + cache_lifetime));
+ /* We could say 'Cache-control: max-age=%d' here if we start doing
+ * http/1.1 */
+ buf_add_printf(buf, "Expires: %s\r\n", expbuf);
+ } else if (cache_lifetime == 0) {
+ /* We could say 'Cache-control: no-cache' here if we start doing
+ * http/1.1 */
+ buf_add_string(buf, "Pragma: no-cache\r\n");
+ }
+ if (extra_headers) {
+ buf_add_string(buf, extra_headers);
+ }
+ buf_add_string(buf, "\r\n");
+
+ connection_buf_add_buf(TO_CONN(conn), buf);
+ buf_free(buf);
+}
+
+/** As write_http_response_header_impl, but sets encoding and content-typed
+ * based on whether the response will be <b>compressed</b> or not. */
+static void
+write_http_response_headers(dir_connection_t *conn, ssize_t length,
+ compress_method_t method,
+ const char *extra_headers, long cache_lifetime)
+{
+ const char *methodname = compression_method_get_name(method);
+ const char *doctype;
+ if (method == NO_METHOD)
+ doctype = "text/plain";
+ else
+ doctype = "application/octet-stream";
+ write_http_response_header_impl(conn, length,
+ doctype,
+ methodname,
+ extra_headers,
+ cache_lifetime);
+}
+
+/** As write_http_response_headers, but assumes extra_headers is NULL */
+static void
+write_http_response_header(dir_connection_t *conn, ssize_t length,
+ compress_method_t method,
+ long cache_lifetime)
+{
+ write_http_response_headers(conn, length, method, NULL, cache_lifetime);
+}
+
+/** Array of compression methods to use (if supported) for serving
+ * precompressed data, ordered from best to worst. */
+static compress_method_t srv_meth_pref_precompressed[] = {
+ LZMA_METHOD,
+ ZSTD_METHOD,
+ ZLIB_METHOD,
+ GZIP_METHOD,
+ NO_METHOD
+};
+
+/** Array of compression methods to use (if supported) for serving
+ * streamed data, ordered from best to worst. */
+static compress_method_t srv_meth_pref_streaming_compression[] = {
+ ZSTD_METHOD,
+ ZLIB_METHOD,
+ GZIP_METHOD,
+ NO_METHOD
+};
+
+/** Array of allowed compression methods to use (if supported) when receiving a
+ * response from a request that was required to be anonymous. */
+static compress_method_t client_meth_allowed_anonymous_compression[] = {
+ ZLIB_METHOD,
+ GZIP_METHOD,
+ NO_METHOD
+};
+
+/** Parse the compression methods listed in an Accept-Encoding header <b>h</b>,
+ * and convert them to a bitfield where compression method x is supported if
+ * and only if 1 << x is set in the bitfield. */
+STATIC unsigned
+parse_accept_encoding_header(const char *h)
+{
+ unsigned result = (1u << NO_METHOD);
+ smartlist_t *methods = smartlist_new();
+ smartlist_split_string(methods, h, ",",
+ SPLIT_SKIP_SPACE|SPLIT_STRIP_SPACE|SPLIT_IGNORE_BLANK, 0);
+
+ SMARTLIST_FOREACH_BEGIN(methods, const char *, m) {
+ compress_method_t method = compression_method_get_by_name(m);
+ if (method != UNKNOWN_METHOD) {
+ tor_assert(((unsigned)method) < 8*sizeof(unsigned));
+ result |= (1u << method);
+ }
+ } SMARTLIST_FOREACH_END(m);
+ SMARTLIST_FOREACH_BEGIN(methods, char *, m) {
+ tor_free(m);
+ } SMARTLIST_FOREACH_END(m);
+ smartlist_free(methods);
+ return result;
+}
+
+/** Array of compression methods to use (if supported) for requesting
+ * compressed data, ordered from best to worst. */
+static compress_method_t client_meth_pref[] = {
+ LZMA_METHOD,
+ ZSTD_METHOD,
+ ZLIB_METHOD,
+ GZIP_METHOD,
+ NO_METHOD
+};
+
+/** Return a newly allocated string containing a comma separated list of
+ * supported encodings. */
+STATIC char *
+accept_encoding_header(void)
+{
+ smartlist_t *methods = smartlist_new();
+ char *header = NULL;
+ compress_method_t method;
+ unsigned i;
+
+ for (i = 0; i < ARRAY_LENGTH(client_meth_pref); ++i) {
+ method = client_meth_pref[i];
+ if (tor_compress_supports_method(method))
+ smartlist_add(methods, (char *)compression_method_get_name(method));
+ }
+
+ header = smartlist_join_strings(methods, ", ", 0, NULL);
+ smartlist_free(methods);
+
+ return header;
+}
+
+/** Decide whether a client would accept the consensus we have.
+ *
+ * Clients can say they only want a consensus if it's signed by more
+ * than half the authorities in a list. They pass this list in
+ * the url as "...consensus/<b>fpr</b>+<b>fpr</b>+<b>fpr</b>".
+ *
+ * <b>fpr</b> may be an abbreviated fingerprint, i.e. only a left substring
+ * of the full authority identity digest. (Only strings of even length,
+ * i.e. encodings of full bytes, are handled correctly. In the case
+ * of an odd number of hex digits the last one is silently ignored.)
+ *
+ * Returns 1 if more than half of the requested authorities signed the
+ * consensus, 0 otherwise.
+ */
+int
+client_likes_consensus(const struct consensus_cache_entry_t *ent,
+ const char *want_url)
+{
+ smartlist_t *voters = smartlist_new();
+ int need_at_least;
+ int have = 0;
+
+ if (consensus_cache_entry_get_voter_id_digests(ent, voters) != 0) {
+ smartlist_free(voters);
+ return 1; // We don't know the voters; assume the client won't mind. */
+ }
+
+ smartlist_t *want_authorities = smartlist_new();
+ dir_split_resource_into_fingerprints(want_url, want_authorities, NULL, 0);
+ need_at_least = smartlist_len(want_authorities)/2+1;
+
+ SMARTLIST_FOREACH_BEGIN(want_authorities, const char *, want_digest) {
+
+ SMARTLIST_FOREACH_BEGIN(voters, const char *, digest) {
+ if (!strcasecmpstart(digest, want_digest)) {
+ have++;
+ break;
+ };
+ } SMARTLIST_FOREACH_END(digest);
+
+ /* early exit, if we already have enough */
+ if (have >= need_at_least)
+ break;
+ } SMARTLIST_FOREACH_END(want_digest);
+
+ SMARTLIST_FOREACH(want_authorities, char *, d, tor_free(d));
+ smartlist_free(want_authorities);
+ SMARTLIST_FOREACH(voters, char *, cp, tor_free(cp));
+ smartlist_free(voters);
+ return (have >= need_at_least);
+}
+
+/** Return the compression level we should use for sending a compressed
+ * response of size <b>n_bytes</b>. */
+STATIC compression_level_t
+choose_compression_level(ssize_t n_bytes)
+{
+ if (! have_been_under_memory_pressure()) {
+ return HIGH_COMPRESSION; /* we have plenty of RAM. */
+ } else if (n_bytes < 0) {
+ return HIGH_COMPRESSION; /* unknown; might be big. */
+ } else if (n_bytes < 1024) {
+ return LOW_COMPRESSION;
+ } else if (n_bytes < 2048) {
+ return MEDIUM_COMPRESSION;
+ } else {
+ return HIGH_COMPRESSION;
+ }
+}
+
+/** Information passed to handle a GET request. */
+typedef struct get_handler_args_t {
+ /** Bitmask of compression methods that the client said (or implied) it
+ * supported. */
+ unsigned compression_supported;
+ /** If nonzero, the time included an if-modified-since header with this
+ * value. */
+ time_t if_modified_since;
+ /** String containing the requested URL or resource. */
+ const char *url;
+ /** String containing the HTTP headers */
+ const char *headers;
+} get_handler_args_t;
+
+/** Entry for handling an HTTP GET request.
+ *
+ * This entry matches a request if "string" is equal to the requested
+ * resource, or if "is_prefix" is true and "string" is a prefix of the
+ * requested resource.
+ *
+ * The 'handler' function is called to handle the request. It receives
+ * an arguments structure, and must return 0 on success or -1 if we should
+ * close the connection.
+ **/
+typedef struct url_table_ent_s {
+ const char *string;
+ int is_prefix;
+ int (*handler)(dir_connection_t *conn, const get_handler_args_t *args);
+} url_table_ent_t;
+
+static int handle_get_frontpage(dir_connection_t *conn,
+ const get_handler_args_t *args);
+static int handle_get_current_consensus(dir_connection_t *conn,
+ const get_handler_args_t *args);
+static int handle_get_status_vote(dir_connection_t *conn,
+ const get_handler_args_t *args);
+static int handle_get_microdesc(dir_connection_t *conn,
+ const get_handler_args_t *args);
+static int handle_get_descriptor(dir_connection_t *conn,
+ const get_handler_args_t *args);
+static int handle_get_keys(dir_connection_t *conn,
+ const get_handler_args_t *args);
+static int handle_get_hs_descriptor_v2(dir_connection_t *conn,
+ const get_handler_args_t *args);
+static int handle_get_robots(dir_connection_t *conn,
+ const get_handler_args_t *args);
+static int handle_get_networkstatus_bridges(dir_connection_t *conn,
+ const get_handler_args_t *args);
+
+/** Table for handling GET requests. */
+static const url_table_ent_t url_table[] = {
+ { "/tor/", 0, handle_get_frontpage },
+ { "/tor/status-vote/current/consensus", 1, handle_get_current_consensus },
+ { "/tor/status-vote/current/", 1, handle_get_status_vote },
+ { "/tor/status-vote/next/", 1, handle_get_status_vote },
+ { "/tor/micro/d/", 1, handle_get_microdesc },
+ { "/tor/server/", 1, handle_get_descriptor },
+ { "/tor/extra/", 1, handle_get_descriptor },
+ { "/tor/keys/", 1, handle_get_keys },
+ { "/tor/rendezvous2/", 1, handle_get_hs_descriptor_v2 },
+ { "/tor/hs/3/", 1, handle_get_hs_descriptor_v3 },
+ { "/tor/robots.txt", 0, handle_get_robots },
+ { "/tor/networkstatus-bridges", 0, handle_get_networkstatus_bridges },
+ { NULL, 0, NULL },
+};
+
+/** 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 404.
+ * Return 0 if we handled this successfully, or -1 if we need to close
+ * the connection. */
+MOCK_IMPL(STATIC int,
+directory_handle_command_get,(dir_connection_t *conn, const char *headers,
+ const char *req_body, size_t req_body_len))
+{
+ char *url, *url_mem, *header;
+ time_t if_modified_since = 0;
+ int zlib_compressed_in_url;
+ unsigned compression_methods_supported;
+
+ /* We ignore the body of a GET request. */
+ (void)req_body;
+ (void)req_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_short_http_response(conn, 400, "Bad request");
+ return 0;
+ }
+ if ((header = http_get_header(headers, "If-Modified-Since: "))) {
+ struct tm tm;
+ if (parse_http_time(header, &tm) == 0) {
+ if (tor_timegm(&tm, &if_modified_since)<0) {
+ if_modified_since = 0;
+ } else {
+ log_debug(LD_DIRSERV, "If-Modified-Since is '%s'.", escaped(header));
+ }
+ }
+ /* The correct behavior on a malformed If-Modified-Since header is to
+ * act as if no If-Modified-Since header had been given. */
+ tor_free(header);
+ }
+ log_debug(LD_DIRSERV,"rewritten url as '%s'.", escaped(url));
+
+ url_mem = url;
+ {
+ size_t url_len = strlen(url);
+
+ zlib_compressed_in_url = url_len > 2 && !strcmp(url+url_len-2, ".z");
+ if (zlib_compressed_in_url) {
+ url[url_len-2] = '\0';
+ }
+ }
+
+ if ((header = http_get_header(headers, "Accept-Encoding: "))) {
+ compression_methods_supported = parse_accept_encoding_header(header);
+ tor_free(header);
+ } else {
+ compression_methods_supported = (1u << NO_METHOD);
+ }
+ if (zlib_compressed_in_url) {
+ compression_methods_supported |= (1u << ZLIB_METHOD);
+ }
+
+ /* Remove all methods that we don't both support. */
+ compression_methods_supported &= tor_compress_get_supported_method_bitmask();
+
+ get_handler_args_t args;
+ args.url = url;
+ args.headers = headers;
+ args.if_modified_since = if_modified_since;
+ args.compression_supported = compression_methods_supported;
+
+ int i, result = -1;
+ for (i = 0; url_table[i].string; ++i) {
+ int match;
+ if (url_table[i].is_prefix) {
+ match = !strcmpstart(url, url_table[i].string);
+ } else {
+ match = !strcmp(url, url_table[i].string);
+ }
+ if (match) {
+ result = url_table[i].handler(conn, &args);
+ goto done;
+ }
+ }
+
+ /* we didn't recognize the url */
+ write_short_http_response(conn, 404, "Not found");
+ result = 0;
+
+ done:
+ tor_free(url_mem);
+ return result;
+}
+
+/** Helper function for GET / or GET /tor/
+ */
+static int
+handle_get_frontpage(dir_connection_t *conn, const get_handler_args_t *args)
+{
+ (void) args; /* unused */
+ const char *frontpage = get_dirportfrontpage();
+
+ if (frontpage) {
+ size_t dlen;
+ dlen = strlen(frontpage);
+ /* Let's return a disclaimer page (users shouldn't use V1 anymore,
+ and caches don't fetch '/', so this is safe). */
+
+ /* [We don't check for write_bucket_low here, since we want to serve
+ * this page no matter what.] */
+ write_http_response_header_impl(conn, dlen, "text/html", "identity",
+ NULL, DIRPORTFRONTPAGE_CACHE_LIFETIME);
+ connection_buf_add(frontpage, dlen, TO_CONN(conn));
+ } else {
+ write_short_http_response(conn, 404, "Not found");
+ }
+ return 0;
+}
+
+/** Warn that the cached consensus <b>consensus</b> of type
+ * <b>flavor</b> is too old and will not be served to clients. Rate-limit the
+ * warning to avoid logging an entry on every request.
+ */
+static void
+warn_consensus_is_too_old(const struct consensus_cache_entry_t *consensus,
+ const char *flavor, time_t now)
+{
+#define TOO_OLD_WARNING_INTERVAL (60*60)
+ static ratelim_t warned = RATELIM_INIT(TOO_OLD_WARNING_INTERVAL);
+ char timestamp[ISO_TIME_LEN+1];
+ time_t valid_until;
+ char *dupes;
+
+ if (consensus_cache_entry_get_valid_until(consensus, &valid_until))
+ return;
+
+ if ((dupes = rate_limit_log(&warned, now))) {
+ format_local_iso_time(timestamp, valid_until);
+ log_warn(LD_DIRSERV, "Our %s%sconsensus is too old, so we will not "
+ "serve it to clients. It was valid until %s local time and we "
+ "continued to serve it for up to 24 hours after it expired.%s",
+ flavor ? flavor : "", flavor ? " " : "", timestamp, dupes);
+ tor_free(dupes);
+ }
+}
+
+/**
+ * Parse a single hex-encoded sha3-256 digest from <b>hex</b> into
+ * <b>digest</b>. Return 0 on success. On failure, report that the hash came
+ * from <b>location</b>, report that we are taking <b>action</b> with it, and
+ * return -1.
+ */
+static int
+parse_one_diff_hash(uint8_t *digest, const char *hex, const char *location,
+ const char *action)
+{
+ if (base16_decode((char*)digest, DIGEST256_LEN, hex, strlen(hex)) ==
+ DIGEST256_LEN) {
+ return 0;
+ } else {
+ log_fn(LOG_PROTOCOL_WARN, LD_DIR,
+ "%s contained bogus digest %s; %s.",
+ location, escaped(hex), action);
+ return -1;
+ }
+}
+
+/** If there is an X-Or-Diff-From-Consensus header included in <b>headers</b>,
+ * set <b>digest_out<b> to a new smartlist containing every 256-bit
+ * hex-encoded digest listed in that header and return 0. Otherwise return
+ * -1. */
+static int
+parse_or_diff_from_header(smartlist_t **digests_out, const char *headers)
+{
+ char *hdr = http_get_header(headers, X_OR_DIFF_FROM_CONSENSUS_HEADER);
+ if (hdr == NULL) {
+ return -1;
+ }
+ smartlist_t *hex_digests = smartlist_new();
+ *digests_out = smartlist_new();
+ smartlist_split_string(hex_digests, hdr, " ",
+ SPLIT_SKIP_SPACE|SPLIT_IGNORE_BLANK, -1);
+ SMARTLIST_FOREACH_BEGIN(hex_digests, const char *, hex) {
+ uint8_t digest[DIGEST256_LEN];
+ if (!parse_one_diff_hash(digest, hex, "X-Or-Diff-From-Consensus header",
+ "ignoring")) {
+ smartlist_add(*digests_out, tor_memdup(digest, sizeof(digest)));
+ }
+ } SMARTLIST_FOREACH_END(hex);
+ SMARTLIST_FOREACH(hex_digests, char *, cp, tor_free(cp));
+ smartlist_free(hex_digests);
+ tor_free(hdr);
+ return 0;
+}
+
+/** Fallback compression method. The fallback compression method is used in
+ * case a client requests a non-compressed document. We only store compressed
+ * documents, so we use this compression method to fetch the document and let
+ * the spooling system do the streaming decompression.
+ */
+#define FALLBACK_COMPRESS_METHOD ZLIB_METHOD
+
+/**
+ * Try to find the best consensus diff possible in order to serve a client
+ * request for a diff from one of the consensuses in <b>digests</b> to the
+ * current consensus of flavor <b>flav</b>. The client supports the
+ * compression methods listed in the <b>compression_methods</b> bitfield:
+ * place the method chosen (if any) into <b>compression_used_out</b>.
+ */
+static struct consensus_cache_entry_t *
+find_best_diff(const smartlist_t *digests, int flav,
+ unsigned compression_methods,
+ compress_method_t *compression_used_out)
+{
+ struct consensus_cache_entry_t *result = NULL;
+
+ SMARTLIST_FOREACH_BEGIN(digests, const uint8_t *, diff_from) {
+ unsigned u;
+ for (u = 0; u < ARRAY_LENGTH(srv_meth_pref_precompressed); ++u) {
+ compress_method_t method = srv_meth_pref_precompressed[u];
+ if (0 == (compression_methods & (1u<<method)))
+ continue; // client doesn't like this one, or we don't have it.
+ if (consdiffmgr_find_diff_from(&result, flav, DIGEST_SHA3_256,
+ diff_from, DIGEST256_LEN,
+ method) == CONSDIFF_AVAILABLE) {
+ tor_assert_nonfatal(result);
+ *compression_used_out = method;
+ return result;
+ }
+ }
+ } SMARTLIST_FOREACH_END(diff_from);
+
+ SMARTLIST_FOREACH_BEGIN(digests, const uint8_t *, diff_from) {
+ if (consdiffmgr_find_diff_from(&result, flav, DIGEST_SHA3_256, diff_from,
+ DIGEST256_LEN, FALLBACK_COMPRESS_METHOD) == CONSDIFF_AVAILABLE) {
+ tor_assert_nonfatal(result);
+ *compression_used_out = FALLBACK_COMPRESS_METHOD;
+ return result;
+ }
+ } SMARTLIST_FOREACH_END(diff_from);
+
+ return NULL;
+}
+
+/** Lookup the cached consensus document by the flavor found in <b>flav</b>.
+ * The preferred set of compression methods should be listed in the
+ * <b>compression_methods</b> bitfield. The compression method chosen (if any)
+ * is stored in <b>compression_used_out</b>. */
+static struct consensus_cache_entry_t *
+find_best_consensus(int flav,
+ unsigned compression_methods,
+ compress_method_t *compression_used_out)
+{
+ struct consensus_cache_entry_t *result = NULL;
+ unsigned u;
+
+ for (u = 0; u < ARRAY_LENGTH(srv_meth_pref_precompressed); ++u) {
+ compress_method_t method = srv_meth_pref_precompressed[u];
+
+ if (0 == (compression_methods & (1u<<method)))
+ continue;
+
+ if (consdiffmgr_find_consensus(&result, flav,
+ method) == CONSDIFF_AVAILABLE) {
+ tor_assert_nonfatal(result);
+ *compression_used_out = method;
+ return result;
+ }
+ }
+
+ if (consdiffmgr_find_consensus(&result, flav,
+ FALLBACK_COMPRESS_METHOD) == CONSDIFF_AVAILABLE) {
+ tor_assert_nonfatal(result);
+ *compression_used_out = FALLBACK_COMPRESS_METHOD;
+ return result;
+ }
+
+ return NULL;
+}
+
+/** Try to find the best supported compression method possible from a given
+ * <b>compression_methods</b>. Return NO_METHOD if no mutually supported
+ * compression method could be found. */
+static compress_method_t
+find_best_compression_method(unsigned compression_methods, int stream)
+{
+ unsigned u;
+ compress_method_t *methods;
+ size_t length;
+
+ if (stream) {
+ methods = srv_meth_pref_streaming_compression;
+ length = ARRAY_LENGTH(srv_meth_pref_streaming_compression);
+ } else {
+ methods = srv_meth_pref_precompressed;
+ length = ARRAY_LENGTH(srv_meth_pref_precompressed);
+ }
+
+ for (u = 0; u < length; ++u) {
+ compress_method_t method = methods[u];
+ if (compression_methods & (1u<<method))
+ return method;
+ }
+
+ return NO_METHOD;
+}
+
+/** Check if any of the digests in <b>digests</b> matches the latest consensus
+ * flavor (given in <b>flavor</b>) that we have available. */
+static int
+digest_list_contains_best_consensus(consensus_flavor_t flavor,
+ const smartlist_t *digests)
+{
+ const networkstatus_t *ns = NULL;
+
+ if (digests == NULL)
+ return 0;
+
+ ns = networkstatus_get_latest_consensus_by_flavor(flavor);
+
+ if (ns == NULL)
+ return 0;
+
+ SMARTLIST_FOREACH_BEGIN(digests, const uint8_t *, digest) {
+ if (tor_memeq(ns->digest_sha3_as_signed, digest, DIGEST256_LEN))
+ return 1;
+ } SMARTLIST_FOREACH_END(digest);
+
+ return 0;
+}
+
+/** Check if the given compression method is allowed for a connection that is
+ * supposed to be anonymous. Returns 1 if the compression method is allowed,
+ * otherwise 0. */
+STATIC int
+allowed_anonymous_connection_compression_method(compress_method_t method)
+{
+ unsigned u;
+
+ for (u = 0; u < ARRAY_LENGTH(client_meth_allowed_anonymous_compression);
+ ++u) {
+ compress_method_t allowed_method =
+ client_meth_allowed_anonymous_compression[u];
+
+ if (! tor_compress_supports_method(allowed_method))
+ continue;
+
+ if (method == allowed_method)
+ return 1;
+ }
+
+ return 0;
+}
+
+/** Log a warning when a remote server has sent us a document using a
+ * compression method that is not allowed for anonymous directory requests. */
+STATIC void
+warn_disallowed_anonymous_compression_method(compress_method_t method)
+{
+ log_fn(LOG_PROTOCOL_WARN, LD_HTTP,
+ "Received a %s HTTP response, which is not "
+ "allowed for anonymous directory requests.",
+ compression_method_get_human_name(method));
+}
+
+/** Encodes the results of parsing a consensus request to figure out what
+ * consensus, and possibly what diffs, the user asked for. */
+typedef struct {
+ /** name of the flavor to retrieve. */
+ char *flavor;
+ /** flavor to retrive, as enum. */
+ consensus_flavor_t flav;
+ /** plus-separated list of authority fingerprints; see
+ * client_likes_consensus(). Aliases the URL in the request passed to
+ * parse_consensus_request(). */
+ const char *want_fps;
+ /** Optionally, a smartlist of sha3 digests-as-signed of the consensuses
+ * to return a diff from. */
+ smartlist_t *diff_from_digests;
+ /** If true, never send a full consensus. If there is no diff, send
+ * a 404 instead. */
+ int diff_only;
+} parsed_consensus_request_t;
+
+/** Remove all data held in <b>req</b>. Do not free <b>req</b> itself, since
+ * it is stack-allocated. */
+static void
+parsed_consensus_request_clear(parsed_consensus_request_t *req)
+{
+ if (!req)
+ return;
+ tor_free(req->flavor);
+ if (req->diff_from_digests) {
+ SMARTLIST_FOREACH(req->diff_from_digests, uint8_t *, d, tor_free(d));
+ smartlist_free(req->diff_from_digests);
+ }
+ memset(req, 0, sizeof(parsed_consensus_request_t));
+}
+
+/**
+ * Parse the URL and relevant headers of <b>args</b> for a current-consensus
+ * request to learn what flavor of consensus we want, what keys it must be
+ * signed with, and what diffs we would accept (or demand) instead. Return 0
+ * on success and -1 on failure.
+ */
+static int
+parse_consensus_request(parsed_consensus_request_t *out,
+ const get_handler_args_t *args)
+{
+ const char *url = args->url;
+ memset(out, 0, sizeof(parsed_consensus_request_t));
+ out->flav = FLAV_NS;
+
+ const char CONSENSUS_URL_PREFIX[] = "/tor/status-vote/current/consensus/";
+ const char CONSENSUS_FLAVORED_PREFIX[] =
+ "/tor/status-vote/current/consensus-";
+
+ /* figure out the flavor if any, and who we wanted to sign the thing */
+ const char *after_flavor = NULL;
+
+ if (!strcmpstart(url, CONSENSUS_FLAVORED_PREFIX)) {
+ const char *f, *cp;
+ f = url + strlen(CONSENSUS_FLAVORED_PREFIX);
+ cp = strchr(f, '/');
+ if (cp) {
+ after_flavor = cp+1;
+ out->flavor = tor_strndup(f, cp-f);
+ } else {
+ out->flavor = tor_strdup(f);
+ }
+ int flav = networkstatus_parse_flavor_name(out->flavor);
+ if (flav < 0)
+ flav = FLAV_NS;
+ out->flav = flav;
+ } else {
+ if (!strcmpstart(url, CONSENSUS_URL_PREFIX))
+ after_flavor = url+strlen(CONSENSUS_URL_PREFIX);
+ }
+
+ /* see whether we've been asked explicitly for a diff from an older
+ * consensus. (The user might also have said that a diff would be okay,
+ * via X-Or-Diff-From-Consensus */
+ const char DIFF_COMPONENT[] = "diff/";
+ char *diff_hash_in_url = NULL;
+ if (after_flavor && !strcmpstart(after_flavor, DIFF_COMPONENT)) {
+ after_flavor += strlen(DIFF_COMPONENT);
+ const char *cp = strchr(after_flavor, '/');
+ if (cp) {
+ diff_hash_in_url = tor_strndup(after_flavor, cp-after_flavor);
+ out->want_fps = cp+1;
+ } else {
+ diff_hash_in_url = tor_strdup(after_flavor);
+ out->want_fps = NULL;
+ }
+ } else {
+ out->want_fps = after_flavor;
+ }
+
+ if (diff_hash_in_url) {
+ uint8_t diff_from[DIGEST256_LEN];
+ out->diff_from_digests = smartlist_new();
+ out->diff_only = 1;
+ int ok = !parse_one_diff_hash(diff_from, diff_hash_in_url, "URL",
+ "rejecting");
+ tor_free(diff_hash_in_url);
+ if (ok) {
+ smartlist_add(out->diff_from_digests,
+ tor_memdup(diff_from, DIGEST256_LEN));
+ } else {
+ return -1;
+ }
+ } else {
+ parse_or_diff_from_header(&out->diff_from_digests, args->headers);
+ }
+
+ return 0;
+}
+
+/** Helper function for GET /tor/status-vote/current/consensus
+ */
+static int
+handle_get_current_consensus(dir_connection_t *conn,
+ const get_handler_args_t *args)
+{
+ const compress_method_t compress_method =
+ find_best_compression_method(args->compression_supported, 0);
+ const time_t if_modified_since = args->if_modified_since;
+ int clear_spool = 0;
+
+ /* v3 network status fetch. */
+ long lifetime = NETWORKSTATUS_CACHE_LIFETIME;
+
+ time_t now = time(NULL);
+ parsed_consensus_request_t req;
+
+ if (parse_consensus_request(&req, args) < 0) {
+ write_short_http_response(conn, 404, "Couldn't parse request");
+ goto done;
+ }
+
+ if (digest_list_contains_best_consensus(req.flav,
+ req.diff_from_digests)) {
+ write_short_http_response(conn, 304, "Not modified");
+ geoip_note_ns_response(GEOIP_REJECT_NOT_MODIFIED);
+ goto done;
+ }
+
+ struct consensus_cache_entry_t *cached_consensus = NULL;
+
+ compress_method_t compression_used = NO_METHOD;
+ if (req.diff_from_digests) {
+ cached_consensus = find_best_diff(req.diff_from_digests, req.flav,
+ args->compression_supported,
+ &compression_used);
+ }
+
+ if (req.diff_only && !cached_consensus) {
+ write_short_http_response(conn, 404, "No such diff available");
+ // XXXX warn_consensus_is_too_old(v, req.flavor, now);
+ geoip_note_ns_response(GEOIP_REJECT_NOT_FOUND);
+ goto done;
+ }
+
+ if (! cached_consensus) {
+ cached_consensus = find_best_consensus(req.flav,
+ args->compression_supported,
+ &compression_used);
+ }
+
+ time_t fresh_until, valid_until;
+ int have_fresh_until = 0, have_valid_until = 0;
+ if (cached_consensus) {
+ have_fresh_until =
+ !consensus_cache_entry_get_fresh_until(cached_consensus, &fresh_until);
+ have_valid_until =
+ !consensus_cache_entry_get_valid_until(cached_consensus, &valid_until);
+ }
+
+ if (cached_consensus && have_valid_until &&
+ !networkstatus_valid_until_is_reasonably_live(valid_until, now)) {
+ write_short_http_response(conn, 404, "Consensus is too old");
+ warn_consensus_is_too_old(cached_consensus, req.flavor, now);
+ geoip_note_ns_response(GEOIP_REJECT_NOT_FOUND);
+ goto done;
+ }
+
+ if (cached_consensus && req.want_fps &&
+ !client_likes_consensus(cached_consensus, req.want_fps)) {
+ write_short_http_response(conn, 404, "Consensus not signed by sufficient "
+ "number of requested authorities");
+ geoip_note_ns_response(GEOIP_REJECT_NOT_ENOUGH_SIGS);
+ goto done;
+ }
+
+ conn->spool = smartlist_new();
+ clear_spool = 1;
+ {
+ spooled_resource_t *spooled;
+ if (cached_consensus) {
+ spooled = spooled_resource_new_from_cache_entry(cached_consensus);
+ smartlist_add(conn->spool, spooled);
+ }
+ }
+
+ lifetime = (have_fresh_until && fresh_until > now) ? fresh_until - now : 0;
+
+ size_t size_guess = 0;
+ int n_expired = 0;
+ dirserv_spool_remove_missing_and_guess_size(conn, if_modified_since,
+ compress_method != NO_METHOD,
+ &size_guess,
+ &n_expired);
+
+ if (!smartlist_len(conn->spool) && !n_expired) {
+ write_short_http_response(conn, 404, "Not found");
+ geoip_note_ns_response(GEOIP_REJECT_NOT_FOUND);
+ goto done;
+ } else if (!smartlist_len(conn->spool)) {
+ write_short_http_response(conn, 304, "Not modified");
+ geoip_note_ns_response(GEOIP_REJECT_NOT_MODIFIED);
+ goto done;
+ }
+
+ if (global_write_bucket_low(TO_CONN(conn), size_guess, 2)) {
+ log_debug(LD_DIRSERV,
+ "Client asked for network status lists, but we've been "
+ "writing too many bytes lately. Sending 503 Dir busy.");
+ write_short_http_response(conn, 503, "Directory busy, try again later");
+ geoip_note_ns_response(GEOIP_REJECT_BUSY);
+ goto done;
+ }
+
+ tor_addr_t addr;
+ if (tor_addr_parse(&addr, (TO_CONN(conn))->address) >= 0) {
+ geoip_note_client_seen(GEOIP_CLIENT_NETWORKSTATUS,
+ &addr, NULL,
+ time(NULL));
+ geoip_note_ns_response(GEOIP_SUCCESS);
+ /* Note that a request for a network status has started, so that we
+ * can measure the download time later on. */
+ if (conn->dirreq_id)
+ geoip_start_dirreq(conn->dirreq_id, size_guess, DIRREQ_TUNNELED);
+ else
+ geoip_start_dirreq(TO_CONN(conn)->global_identifier, size_guess,
+ DIRREQ_DIRECT);
+ }
+
+ /* Use this header to tell caches that the response depends on the
+ * X-Or-Diff-From-Consensus header (or lack thereof). */
+ const char vary_header[] = "Vary: X-Or-Diff-From-Consensus\r\n";
+
+ clear_spool = 0;
+
+ // The compress_method might have been NO_METHOD, but we store the data
+ // compressed. Decompress them using `compression_used`. See fallback code in
+ // find_best_consensus() and find_best_diff().
+ write_http_response_headers(conn, -1,
+ compress_method == NO_METHOD ?
+ NO_METHOD : compression_used,
+ vary_header,
+ smartlist_len(conn->spool) == 1 ? lifetime : 0);
+
+ if (compress_method == NO_METHOD && smartlist_len(conn->spool))
+ conn->compress_state = tor_compress_new(0, compression_used,
+ HIGH_COMPRESSION);
+
+ /* Prime the connection with some data. */
+ const int initial_flush_result = connection_dirserv_flushed_some(conn);
+ tor_assert_nonfatal(initial_flush_result == 0);
+ goto done;
+
+ done:
+ parsed_consensus_request_clear(&req);
+ if (clear_spool) {
+ dir_conn_clear_spool(conn);
+ }
+ return 0;
+}
+
+/** Helper function for GET /tor/status-vote/{current,next}/...
+ */
+static int
+handle_get_status_vote(dir_connection_t *conn, const get_handler_args_t *args)
+{
+ const char *url = args->url;
+ {
+ ssize_t body_len = 0;
+ ssize_t estimated_len = 0;
+ int lifetime = 60; /* XXXX?? should actually use vote intervals. */
+ /* This smartlist holds strings that we can compress on the fly. */
+ smartlist_t *items = smartlist_new();
+ /* This smartlist holds cached_dir_t objects that have a precompressed
+ * deflated version. */
+ smartlist_t *dir_items = smartlist_new();
+ dirvote_dirreq_get_status_vote(url, items, dir_items);
+ if (!smartlist_len(dir_items) && !smartlist_len(items)) {
+ write_short_http_response(conn, 404, "Not found");
+ goto vote_done;
+ }
+
+ /* We're sending items from at most one kind of source */
+ tor_assert_nonfatal(smartlist_len(items) == 0 ||
+ smartlist_len(dir_items) == 0);
+
+ int streaming;
+ unsigned mask;
+ if (smartlist_len(items)) {
+ /* We're taking strings and compressing them on the fly. */
+ streaming = 1;
+ mask = ~0u;
+ } else {
+ /* We're taking cached_dir_t objects. We only have them uncompressed
+ * or deflated. */
+ streaming = 0;
+ mask = (1u<<NO_METHOD) | (1u<<ZLIB_METHOD);
+ }
+ const compress_method_t compress_method = find_best_compression_method(
+ args->compression_supported&mask, streaming);
+
+ SMARTLIST_FOREACH(dir_items, cached_dir_t *, d,
+ body_len += compress_method != NO_METHOD ?
+ d->dir_compressed_len : d->dir_len);
+ estimated_len += body_len;
+ SMARTLIST_FOREACH(items, const char *, item, {
+ size_t ln = strlen(item);
+ if (compress_method != NO_METHOD) {
+ estimated_len += ln/2;
+ } else {
+ body_len += ln; estimated_len += ln;
+ }
+ });
+
+ if (global_write_bucket_low(TO_CONN(conn), estimated_len, 2)) {
+ write_short_http_response(conn, 503, "Directory busy, try again later");
+ goto vote_done;
+ }
+ write_http_response_header(conn, body_len ? body_len : -1,
+ compress_method,
+ lifetime);
+
+ if (smartlist_len(items)) {
+ if (compress_method != NO_METHOD) {
+ conn->compress_state = tor_compress_new(1, compress_method,
+ choose_compression_level(estimated_len));
+ SMARTLIST_FOREACH(items, const char *, c,
+ connection_buf_add_compress(c, strlen(c), conn, 0));
+ connection_buf_add_compress("", 0, conn, 1);
+ } else {
+ SMARTLIST_FOREACH(items, const char *, c,
+ connection_buf_add(c, strlen(c), TO_CONN(conn)));
+ }
+ } else {
+ SMARTLIST_FOREACH(dir_items, cached_dir_t *, d,
+ connection_buf_add(compress_method != NO_METHOD ?
+ d->dir_compressed : d->dir,
+ compress_method != NO_METHOD ?
+ d->dir_compressed_len : d->dir_len,
+ TO_CONN(conn)));
+ }
+ vote_done:
+ smartlist_free(items);
+ smartlist_free(dir_items);
+ goto done;
+ }
+ done:
+ return 0;
+}
+
+/** Helper function for GET /tor/micro/d/...
+ */
+static int
+handle_get_microdesc(dir_connection_t *conn, const get_handler_args_t *args)
+{
+ const char *url = args->url;
+ const compress_method_t compress_method =
+ find_best_compression_method(args->compression_supported, 1);
+ int clear_spool = 1;
+ {
+ conn->spool = smartlist_new();
+
+ dir_split_resource_into_spoolable(url+strlen("/tor/micro/d/"),
+ DIR_SPOOL_MICRODESC,
+ conn->spool, NULL,
+ DSR_DIGEST256|DSR_BASE64|DSR_SORT_UNIQ);
+
+ size_t size_guess = 0;
+ dirserv_spool_remove_missing_and_guess_size(conn, 0,
+ compress_method != NO_METHOD,
+ &size_guess, NULL);
+ if (smartlist_len(conn->spool) == 0) {
+ write_short_http_response(conn, 404, "Not found");
+ goto done;
+ }
+ if (global_write_bucket_low(TO_CONN(conn), size_guess, 2)) {
+ log_info(LD_DIRSERV,
+ "Client asked for server descriptors, but we've been "
+ "writing too many bytes lately. Sending 503 Dir busy.");
+ write_short_http_response(conn, 503, "Directory busy, try again later");
+ goto done;
+ }
+
+ clear_spool = 0;
+ write_http_response_header(conn, -1,
+ compress_method,
+ MICRODESC_CACHE_LIFETIME);
+
+ if (compress_method != NO_METHOD)
+ conn->compress_state = tor_compress_new(1, compress_method,
+ choose_compression_level(size_guess));
+
+ const int initial_flush_result = connection_dirserv_flushed_some(conn);
+ tor_assert_nonfatal(initial_flush_result == 0);
+ goto done;
+ }
+
+ done:
+ if (clear_spool) {
+ dir_conn_clear_spool(conn);
+ }
+ return 0;
+}
+
+/** Helper function for GET /tor/{server,extra}/...
+ */
+static int
+handle_get_descriptor(dir_connection_t *conn, const get_handler_args_t *args)
+{
+ const char *url = args->url;
+ const compress_method_t compress_method =
+ find_best_compression_method(args->compression_supported, 1);
+ const or_options_t *options = get_options();
+ int clear_spool = 1;
+ if (!strcmpstart(url,"/tor/server/") ||
+ (!options->BridgeAuthoritativeDir &&
+ !options->BridgeRelay && !strcmpstart(url,"/tor/extra/"))) {
+ int res;
+ const char *msg = NULL;
+ int cache_lifetime = 0;
+ int is_extra = !strcmpstart(url,"/tor/extra/");
+ url += is_extra ? strlen("/tor/extra/") : strlen("/tor/server/");
+ dir_spool_source_t source;
+ time_t publish_cutoff = 0;
+ if (!strcmpstart(url, "d/")) {
+ source =
+ is_extra ? DIR_SPOOL_EXTRA_BY_DIGEST : DIR_SPOOL_SERVER_BY_DIGEST;
+ } else {
+ source =
+ is_extra ? DIR_SPOOL_EXTRA_BY_FP : DIR_SPOOL_SERVER_BY_FP;
+ /* We only want to apply a publish cutoff when we're requesting
+ * resources by fingerprint. */
+ publish_cutoff = time(NULL) - ROUTER_MAX_AGE_TO_PUBLISH;
+ }
+
+ conn->spool = smartlist_new();
+ res = dirserv_get_routerdesc_spool(conn->spool, url,
+ source,
+ connection_dir_is_encrypted(conn),
+ &msg);
+
+ if (!strcmpstart(url, "all")) {
+ cache_lifetime = FULL_DIR_CACHE_LIFETIME;
+ } else if (smartlist_len(conn->spool) == 1) {
+ cache_lifetime = ROUTERDESC_BY_DIGEST_CACHE_LIFETIME;
+ }
+
+ size_t size_guess = 0;
+ int n_expired = 0;
+ dirserv_spool_remove_missing_and_guess_size(conn, publish_cutoff,
+ compress_method != NO_METHOD,
+ &size_guess, &n_expired);
+
+ /* If we are the bridge authority and the descriptor is a bridge
+ * descriptor, remember that we served this descriptor for desc stats. */
+ /* XXXX it's a bit of a kludge to have this here. */
+ if (get_options()->BridgeAuthoritativeDir &&
+ source == DIR_SPOOL_SERVER_BY_FP) {
+ SMARTLIST_FOREACH_BEGIN(conn->spool, spooled_resource_t *, spooled) {
+ const routerinfo_t *router =
+ router_get_by_id_digest((const char *)spooled->digest);
+ /* router can be NULL here when the bridge auth is asked for its own
+ * descriptor. */
+ if (router && router->purpose == ROUTER_PURPOSE_BRIDGE)
+ rep_hist_note_desc_served(router->cache_info.identity_digest);
+ } SMARTLIST_FOREACH_END(spooled);
+ }
+
+ if (res < 0 || size_guess == 0 || smartlist_len(conn->spool) == 0) {
+ if (msg == NULL)
+ msg = "Not found";
+ write_short_http_response(conn, 404, msg);
+ } else {
+ if (global_write_bucket_low(TO_CONN(conn), size_guess, 2)) {
+ log_info(LD_DIRSERV,
+ "Client asked for server descriptors, but we've been "
+ "writing too many bytes lately. Sending 503 Dir busy.");
+ write_short_http_response(conn, 503,
+ "Directory busy, try again later");
+ dir_conn_clear_spool(conn);
+ goto done;
+ }
+ write_http_response_header(conn, -1, compress_method, cache_lifetime);
+ if (compress_method != NO_METHOD)
+ conn->compress_state = tor_compress_new(1, compress_method,
+ choose_compression_level(size_guess));
+ clear_spool = 0;
+ /* Prime the connection with some data. */
+ int initial_flush_result = connection_dirserv_flushed_some(conn);
+ tor_assert_nonfatal(initial_flush_result == 0);
+ }
+ goto done;
+ }
+ done:
+ if (clear_spool)
+ dir_conn_clear_spool(conn);
+ return 0;
+}
+
+/** Helper function for GET /tor/keys/...
+ */
+static int
+handle_get_keys(dir_connection_t *conn, const get_handler_args_t *args)
+{
+ const char *url = args->url;
+ const compress_method_t compress_method =
+ find_best_compression_method(args->compression_supported, 1);
+ const time_t if_modified_since = args->if_modified_since;
+ {
+ smartlist_t *certs = smartlist_new();
+ ssize_t len = -1;
+ if (!strcmp(url, "/tor/keys/all")) {
+ authority_cert_get_all(certs);
+ } else if (!strcmp(url, "/tor/keys/authority")) {
+ authority_cert_t *cert = get_my_v3_authority_cert();
+ if (cert)
+ smartlist_add(certs, cert);
+ } else if (!strcmpstart(url, "/tor/keys/fp/")) {
+ smartlist_t *fps = smartlist_new();
+ dir_split_resource_into_fingerprints(url+strlen("/tor/keys/fp/"),
+ fps, NULL,
+ DSR_HEX|DSR_SORT_UNIQ);
+ SMARTLIST_FOREACH(fps, char *, d, {
+ authority_cert_t *c = authority_cert_get_newest_by_id(d);
+ if (c) smartlist_add(certs, c);
+ tor_free(d);
+ });
+ smartlist_free(fps);
+ } else if (!strcmpstart(url, "/tor/keys/sk/")) {
+ smartlist_t *fps = smartlist_new();
+ dir_split_resource_into_fingerprints(url+strlen("/tor/keys/sk/"),
+ fps, NULL,
+ DSR_HEX|DSR_SORT_UNIQ);
+ SMARTLIST_FOREACH(fps, char *, d, {
+ authority_cert_t *c = authority_cert_get_by_sk_digest(d);
+ if (c) smartlist_add(certs, c);
+ tor_free(d);
+ });
+ smartlist_free(fps);
+ } else if (!strcmpstart(url, "/tor/keys/fp-sk/")) {
+ smartlist_t *fp_sks = smartlist_new();
+ dir_split_resource_into_fingerprint_pairs(url+strlen("/tor/keys/fp-sk/"),
+ fp_sks);
+ SMARTLIST_FOREACH(fp_sks, fp_pair_t *, pair, {
+ authority_cert_t *c = authority_cert_get_by_digests(pair->first,
+ pair->second);
+ if (c) smartlist_add(certs, c);
+ tor_free(pair);
+ });
+ smartlist_free(fp_sks);
+ } else {
+ write_short_http_response(conn, 400, "Bad request");
+ goto keys_done;
+ }
+ if (!smartlist_len(certs)) {
+ write_short_http_response(conn, 404, "Not found");
+ goto keys_done;
+ }
+ SMARTLIST_FOREACH(certs, authority_cert_t *, c,
+ if (c->cache_info.published_on < if_modified_since)
+ SMARTLIST_DEL_CURRENT(certs, c));
+ if (!smartlist_len(certs)) {
+ write_short_http_response(conn, 304, "Not modified");
+ goto keys_done;
+ }
+ len = 0;
+ SMARTLIST_FOREACH(certs, authority_cert_t *, c,
+ len += c->cache_info.signed_descriptor_len);
+
+ if (global_write_bucket_low(TO_CONN(conn),
+ compress_method != NO_METHOD ? len/2 : len,
+ 2)) {
+ write_short_http_response(conn, 503, "Directory busy, try again later");
+ goto keys_done;
+ }
+
+ write_http_response_header(conn,
+ compress_method != NO_METHOD ? -1 : len,
+ compress_method,
+ 60*60);
+ if (compress_method != NO_METHOD) {
+ conn->compress_state = tor_compress_new(1, compress_method,
+ choose_compression_level(len));
+ SMARTLIST_FOREACH(certs, authority_cert_t *, c,
+ connection_buf_add_compress(
+ c->cache_info.signed_descriptor_body,
+ c->cache_info.signed_descriptor_len,
+ conn, 0));
+ connection_buf_add_compress("", 0, conn, 1);
+ } else {
+ SMARTLIST_FOREACH(certs, authority_cert_t *, c,
+ connection_buf_add(c->cache_info.signed_descriptor_body,
+ c->cache_info.signed_descriptor_len,
+ TO_CONN(conn)));
+ }
+ keys_done:
+ smartlist_free(certs);
+ goto done;
+ }
+ done:
+ return 0;
+}
+
+/** Helper function for GET /tor/rendezvous2/
+ */
+static int
+handle_get_hs_descriptor_v2(dir_connection_t *conn,
+ const get_handler_args_t *args)
+{
+ const char *url = args->url;
+ if (connection_dir_is_encrypted(conn)) {
+ /* Handle v2 rendezvous descriptor fetch request. */
+ const char *descp;
+ const char *query = url + strlen("/tor/rendezvous2/");
+ if (rend_valid_descriptor_id(query)) {
+ log_info(LD_REND, "Got a v2 rendezvous descriptor request for ID '%s'",
+ safe_str(escaped(query)));
+ switch (rend_cache_lookup_v2_desc_as_dir(query, &descp)) {
+ case 1: /* valid */
+ write_http_response_header(conn, strlen(descp), NO_METHOD, 0);
+ connection_buf_add(descp, strlen(descp), TO_CONN(conn));
+ break;
+ case 0: /* well-formed but not present */
+ write_short_http_response(conn, 404, "Not found");
+ break;
+ case -1: /* not well-formed */
+ write_short_http_response(conn, 400, "Bad request");
+ break;
+ }
+ } else { /* not well-formed */
+ write_short_http_response(conn, 400, "Bad request");
+ }
+ goto done;
+ } else {
+ /* Not encrypted! */
+ write_short_http_response(conn, 404, "Not found");
+ }
+ done:
+ return 0;
+}
+
+/** Helper function for GET /tor/hs/3/<z>. Only for version 3.
+ */
+STATIC int
+handle_get_hs_descriptor_v3(dir_connection_t *conn,
+ const get_handler_args_t *args)
+{
+ int retval;
+ const char *desc_str = NULL;
+ const char *pubkey_str = NULL;
+ const char *url = args->url;
+
+ /* Reject unencrypted dir connections */
+ if (!connection_dir_is_encrypted(conn)) {
+ write_short_http_response(conn, 404, "Not found");
+ goto done;
+ }
+
+ /* After the path prefix follows the base64 encoded blinded pubkey which we
+ * use to get the descriptor from the cache. Skip the prefix and get the
+ * pubkey. */
+ tor_assert(!strcmpstart(url, "/tor/hs/3/"));
+ pubkey_str = url + strlen("/tor/hs/3/");
+ retval = hs_cache_lookup_as_dir(HS_VERSION_THREE,
+ pubkey_str, &desc_str);
+ if (retval <= 0 || desc_str == NULL) {
+ write_short_http_response(conn, 404, "Not found");
+ goto done;
+ }
+
+ /* Found requested descriptor! Pass it to this nice client. */
+ write_http_response_header(conn, strlen(desc_str), NO_METHOD, 0);
+ connection_buf_add(desc_str, strlen(desc_str), TO_CONN(conn));
+
+ done:
+ return 0;
+}
+
+/** Helper function for GET /tor/networkstatus-bridges
+ */
+static int
+handle_get_networkstatus_bridges(dir_connection_t *conn,
+ const get_handler_args_t *args)
+{
+ const char *headers = args->headers;
+
+ const or_options_t *options = get_options();
+ if (options->BridgeAuthoritativeDir &&
+ options->BridgePassword_AuthDigest_ &&
+ connection_dir_is_encrypted(conn)) {
+ char *status;
+ char digest[DIGEST256_LEN];
+
+ char *header = http_get_header(headers, "Authorization: Basic ");
+ if (header)
+ crypto_digest256(digest, header, strlen(header), DIGEST_SHA256);
+
+ /* now make sure the password is there and right */
+ if (!header ||
+ tor_memneq(digest,
+ options->BridgePassword_AuthDigest_, DIGEST256_LEN)) {
+ write_short_http_response(conn, 404, "Not found");
+ tor_free(header);
+ goto done;
+ }
+ tor_free(header);
+
+ /* all happy now. send an answer. */
+ status = networkstatus_getinfo_by_purpose("bridge", time(NULL));
+ size_t dlen = strlen(status);
+ write_http_response_header(conn, dlen, NO_METHOD, 0);
+ connection_buf_add(status, dlen, TO_CONN(conn));
+ tor_free(status);
+ goto done;
+ }
+ done:
+ return 0;
+}
+
+/** Helper function for GET robots.txt or /tor/robots.txt */
+static int
+handle_get_robots(dir_connection_t *conn, const get_handler_args_t *args)
+{
+ (void)args;
+ {
+ const char robots[] = "User-agent: *\r\nDisallow: /\r\n";
+ size_t len = strlen(robots);
+ write_http_response_header(conn, len, NO_METHOD, ROBOTS_CACHE_LIFETIME);
+ connection_buf_add(robots, len, TO_CONN(conn));
+ }
+ return 0;
+}
+
+/* Given the <b>url</b> from a POST request, try to extract the version number
+ * using the provided <b>prefix</b>. The version should be after the prefix and
+ * ending with the separator "/". For instance:
+ * /tor/hs/3/publish
+ *
+ * On success, <b>end_pos</b> points to the position right after the version
+ * was found. On error, it is set to NULL.
+ *
+ * Return version on success else negative value. */
+STATIC int
+parse_hs_version_from_post(const char *url, const char *prefix,
+ const char **end_pos)
+{
+ int ok;
+ unsigned long version;
+ const char *start;
+ char *end = NULL;
+
+ tor_assert(url);
+ tor_assert(prefix);
+ tor_assert(end_pos);
+
+ /* Check if the prefix does start the url. */
+ if (strcmpstart(url, prefix)) {
+ goto err;
+ }
+ /* Move pointer to the end of the prefix string. */
+ start = url + strlen(prefix);
+ /* Try this to be the HS version and if we are still at the separator, next
+ * will be move to the right value. */
+ version = tor_parse_long(start, 10, 0, INT_MAX, &ok, &end);
+ if (!ok) {
+ goto err;
+ }
+
+ *end_pos = end;
+ return (int) version;
+ err:
+ *end_pos = NULL;
+ return -1;
+}
+
+/* Handle the POST request for a hidden service descripror. The request is in
+ * <b>url</b>, the body of the request is in <b>body</b>. Return 200 on success
+ * else return 400 indicating a bad request. */
+STATIC int
+handle_post_hs_descriptor(const char *url, const char *body)
+{
+ int version;
+ const char *end_pos;
+
+ tor_assert(url);
+ tor_assert(body);
+
+ version = parse_hs_version_from_post(url, "/tor/hs/", &end_pos);
+ if (version < 0) {
+ goto err;
+ }
+
+ /* We have a valid version number, now make sure it's a publish request. Use
+ * the end position just after the version and check for the command. */
+ if (strcmpstart(end_pos, "/publish")) {
+ goto err;
+ }
+
+ switch (version) {
+ case HS_VERSION_THREE:
+ if (hs_cache_store_as_dir(body) < 0) {
+ goto err;
+ }
+ log_info(LD_REND, "Publish request for HS descriptor handled "
+ "successfully.");
+ break;
+ default:
+ /* Unsupported version, return a bad request. */
+ goto err;
+ }
+
+ return 200;
+ err:
+ /* Bad request. */
+ return 400;
+}
+
+/** 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. */
+MOCK_IMPL(STATIC int,
+directory_handle_command_post,(dir_connection_t *conn, const char *headers,
+ const char *body, size_t body_len))
+{
+ char *url = NULL;
+ const or_options_t *options = get_options();
+
+ log_debug(LD_DIRSERV,"Received POST command.");
+
+ conn->base_.state = DIR_CONN_STATE_SERVER_WRITING;
+
+ if (!public_server_mode(options)) {
+ log_info(LD_DIR, "Rejected dir post request from %s "
+ "since we're not a public relay.", conn->base_.address);
+ write_short_http_response(conn, 503, "Not acting as a public relay");
+ goto done;
+ }
+
+ if (parse_http_url(headers, &url) < 0) {
+ write_short_http_response(conn, 400, "Bad request");
+ return 0;
+ }
+ log_debug(LD_DIRSERV,"rewritten url as '%s'.", escaped(url));
+
+ /* Handle v2 rendezvous service publish request. */
+ if (connection_dir_is_encrypted(conn) &&
+ !strcmpstart(url,"/tor/rendezvous2/publish")) {
+ if (rend_cache_store_v2_desc_as_dir(body) < 0) {
+ log_warn(LD_REND, "Rejected v2 rend descriptor (body size %d) from %s.",
+ (int)body_len, conn->base_.address);
+ write_short_http_response(conn, 400,
+ "Invalid v2 service descriptor rejected");
+ } else {
+ write_short_http_response(conn, 200, "Service descriptor (v2) stored");
+ log_info(LD_REND, "Handled v2 rendezvous descriptor post: accepted");
+ }
+ goto done;
+ }
+
+ /* Handle HS descriptor publish request. */
+ /* XXX: This should be disabled with a consensus param until we want to
+ * the prop224 be deployed and thus use. */
+ if (connection_dir_is_encrypted(conn) && !strcmpstart(url, "/tor/hs/")) {
+ const char *msg = "HS descriptor stored successfully.";
+
+ /* We most probably have a publish request for an HS descriptor. */
+ int code = handle_post_hs_descriptor(url, body);
+ if (code != 200) {
+ msg = "Invalid HS descriptor. Rejected.";
+ }
+ write_short_http_response(conn, code, msg);
+ goto done;
+ }
+
+ if (!authdir_mode(options)) {
+ /* we just provide cached directories; we don't want to
+ * receive anything. */
+ write_short_http_response(conn, 400, "Nonauthoritative directory does not "
+ "accept posted server descriptors");
+ goto done;
+ }
+
+ if (authdir_mode(options) &&
+ !strcmp(url,"/tor/")) { /* server descriptor post */
+ const char *msg = "[None]";
+ uint8_t purpose = authdir_mode_bridge(options) ?
+ ROUTER_PURPOSE_BRIDGE : ROUTER_PURPOSE_GENERAL;
+ was_router_added_t r = dirserv_add_multiple_descriptors(body, purpose,
+ conn->base_.address, &msg);
+ tor_assert(msg);
+
+ if (r == ROUTER_ADDED_SUCCESSFULLY) {
+ write_short_http_response(conn, 200, msg);
+ } else if (WRA_WAS_OUTDATED(r)) {
+ write_http_response_header_impl(conn, -1, NULL, NULL,
+ "X-Descriptor-Not-New: Yes\r\n", -1);
+ } else {
+ log_info(LD_DIRSERV,
+ "Rejected router descriptor or extra-info from %s "
+ "(\"%s\").",
+ conn->base_.address, msg);
+ write_short_http_response(conn, 400, msg);
+ }
+ goto done;
+ }
+
+ if (authdir_mode_v3(options) &&
+ !strcmp(url,"/tor/post/vote")) { /* v3 networkstatus vote */
+ const char *msg = "OK";
+ int status;
+ if (dirvote_add_vote(body, &msg, &status)) {
+ write_short_http_response(conn, status, "Vote stored");
+ } else {
+ tor_assert(msg);
+ log_warn(LD_DIRSERV, "Rejected vote from %s (\"%s\").",
+ conn->base_.address, msg);
+ write_short_http_response(conn, status, msg);
+ }
+ goto done;
+ }
+
+ if (authdir_mode_v3(options) &&
+ !strcmp(url,"/tor/post/consensus-signature")) { /* sigs on consensus. */
+ const char *msg = NULL;
+ if (dirvote_add_signatures(body, conn->base_.address, &msg)>=0) {
+ write_short_http_response(conn, 200, msg?msg:"Signatures stored");
+ } else {
+ log_warn(LD_DIR, "Unable to store signatures posted by %s: %s",
+ conn->base_.address, msg?msg:"???");
+ write_short_http_response(conn, 400,
+ msg?msg:"Unable to store signatures");
+ }
+ goto done;
+ }
+
+ /* we didn't recognize the url */
+ write_short_http_response(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 (connection_fetch_from_buf_http(TO_CONN(conn),
+ &headers, MAX_HEADERS_SIZE,
+ &body, &body_len, MAX_DIR_UL_SIZE, 0)) {
+ case -1: /* overflow */
+ log_warn(LD_DIRSERV,
+ "Request too large from address '%s' to DirPort. Closing.",
+ safe_str(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));
+ // we should escape headers here as well,
+ // but we can't call escaped() twice, as it uses the same buffer
+ //log_debug(LD_DIRSERV,"headers %s, body %s.", headers, escaped(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);
+
++ if (conn->base_.marked_for_close)
++ return 0;
++
+ /* Note that we have finished writing the directory response. For direct
+ * connections this means we're done; for tunneled connections it's only
+ * an intermediate step. */
+ if (conn->dirreq_id)
+ geoip_change_dirreq_state(conn->dirreq_id, DIRREQ_TUNNELED,
+ DIRREQ_FLUSHING_DIR_CONN_FINISHED);
+ else
+ geoip_change_dirreq_state(TO_CONN(conn)->global_identifier,
+ DIRREQ_DIRECT,
+ DIRREQ_FLUSHING_DIR_CONN_FINISHED);
+ switch (conn->base_.state) {
+ case DIR_CONN_STATE_CONNECTING:
+ case DIR_CONN_STATE_CLIENT_SENDING:
+ log_debug(LD_DIR,"client finished sending command.");
+ conn->base_.state = DIR_CONN_STATE_CLIENT_READING;
+ return 0;
+ case DIR_CONN_STATE_SERVER_WRITING:
+ if (conn->spool) {
+ log_warn(LD_BUG, "Emptied a dirserv buffer, but it's still spooling!");
+ connection_mark_for_close(TO_CONN(conn));
+ } else {
+ log_debug(LD_DIRSERV, "Finished writing server response. Closing.");
+ connection_mark_for_close(TO_CONN(conn));
+ }
+ return 0;
+ default:
+ log_warn(LD_BUG,"called in unexpected state %d.",
+ conn->base_.state);
+ tor_fragile_assert();
+ return -1;
+ }
+ return 0;
+}
+
+/* We just got a new consensus! If there are other in-progress requests
+ * for this consensus flavor (for example because we launched several in
+ * parallel), cancel them.
+ *
+ * We do this check here (not just in
+ * connection_ap_handshake_attach_circuit()) to handle the edge case where
+ * a consensus fetch begins and ends before some other one tries to attach to
+ * a circuit, in which case the other one won't know that we're all happy now.
+ *
+ * Don't mark the conn that just gave us the consensus -- otherwise we
+ * would end up double-marking it when it cleans itself up.
+ */
+static void
+connection_dir_close_consensus_fetches(dir_connection_t *except_this_one,
+ const char *resource)
+{
+ smartlist_t *conns_to_close =
+ connection_dir_list_by_purpose_and_resource(DIR_PURPOSE_FETCH_CONSENSUS,
+ resource);
+ SMARTLIST_FOREACH_BEGIN(conns_to_close, dir_connection_t *, d) {
+ if (d == except_this_one)
+ continue;
+ log_info(LD_DIR, "Closing consensus fetch (to %s) since one "
+ "has just arrived.", TO_CONN(d)->address);
+ connection_mark_for_close(TO_CONN(d));
+ } SMARTLIST_FOREACH_END(d);
+ smartlist_free(conns_to_close);
+}
+
+/** Connected handler for directory connections: begin sending data to the
+ * server, and return 0.
+ * Only used when connections don't immediately connect. */
+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);
+
+ /* start flushing conn */
+ conn->base_.state = DIR_CONN_STATE_CLIENT_SENDING;
+ return 0;
+}
+
+/** Decide which download schedule we want to use based on descriptor type
+ * in <b>dls</b> and <b>options</b>.
+ *
+ * Then, return the initial delay for that download schedule, in seconds.
+ *
+ * Helper function for download_status_increment_failure(),
+ * download_status_reset(), and download_status_increment_attempt(). */
+STATIC int
+find_dl_min_delay(const download_status_t *dls, const or_options_t *options)
+{
+ tor_assert(dls);
+ tor_assert(options);
+
+ switch (dls->schedule) {
+ case DL_SCHED_GENERIC:
+ /* Any other directory document */
+ if (dir_server_mode(options)) {
+ /* A directory authority or directory mirror */
+ return options->TestingServerDownloadInitialDelay;
+ } else {
+ return options->TestingClientDownloadInitialDelay;
+ }
+ case DL_SCHED_CONSENSUS:
+ if (!networkstatus_consensus_can_use_multiple_directories(options)) {
+ /* A public relay */
+ return options->TestingServerConsensusDownloadInitialDelay;
+ } else {
+ /* A client or bridge */
+ if (networkstatus_consensus_is_bootstrapping(time(NULL))) {
+ /* During bootstrapping */
+ if (!networkstatus_consensus_can_use_extra_fallbacks(options)) {
+ /* A bootstrapping client without extra fallback directories */
+ return options->
+ ClientBootstrapConsensusAuthorityOnlyDownloadInitialDelay;
+ } else if (dls->want_authority) {
+ /* A bootstrapping client with extra fallback directories, but
+ * connecting to an authority */
+ return
+ options->ClientBootstrapConsensusAuthorityDownloadInitialDelay;
+ } else {
+ /* A bootstrapping client connecting to extra fallback directories
+ */
+ return
+ options->ClientBootstrapConsensusFallbackDownloadInitialDelay;
+ }
+ } else {
+ /* A client with a reasonably live consensus, with or without
+ * certificates */
+ return options->TestingClientConsensusDownloadInitialDelay;
+ }
+ }
+ case DL_SCHED_BRIDGE:
+ if (options->UseBridges && num_bridges_usable(0) > 0) {
+ /* A bridge client that is sure that one or more of its bridges are
+ * running can afford to wait longer to update bridge descriptors. */
+ return options->TestingBridgeDownloadInitialDelay;
+ } else {
+ /* A bridge client which might have no running bridges, must try to
+ * get bridge descriptors straight away. */
+ return options->TestingBridgeBootstrapDownloadInitialDelay;
+ }
+ default:
+ tor_assert(0);
+ }
+
+ /* Impossible, but gcc will fail with -Werror without a `return`. */
+ return 0;
+}
+
+/** As next_random_exponential_delay() below, but does not compute a random
+ * value. Instead, compute the range of values that
+ * next_random_exponential_delay() should use when computing its random value.
+ * Store the low bound into *<b>low_bound_out</b>, and the high bound into
+ * *<b>high_bound_out</b>. Guarantees that the low bound is strictly less
+ * than the high bound. */
+STATIC void
+next_random_exponential_delay_range(int *low_bound_out,
+ int *high_bound_out,
+ int delay,
+ int base_delay)
+{
+ // This is the "decorrelated jitter" approach, from
+ // https://www.awsarchitectureblog.com/2015/03/backoff.html
+ // The formula is
+ // sleep = min(cap, random_between(base, sleep * 3))
+
+ const int delay_times_3 = delay < INT_MAX/3 ? delay * 3 : INT_MAX;
+ *low_bound_out = base_delay;
+ if (delay_times_3 > base_delay) {
+ *high_bound_out = delay_times_3;
+ } else {
+ *high_bound_out = base_delay+1;
+ }
+}
+
+/** Advance one delay step. The algorithm will generate a random delay,
+ * such that each failure is possibly (random) longer than the ones before.
+ *
+ * We then clamp that value to be no larger than max_delay, and return it.
+ *
+ * The <b>base_delay</b> parameter is lowest possible delay time (can't be
+ * zero); the <b>backoff_position</b> parameter is the number of times we've
+ * generated a delay; and the <b>delay</b> argument is the most recently used
+ * delay.
+ */
+STATIC int
+next_random_exponential_delay(int delay,
+ int base_delay)
+{
+ /* Check preconditions */
+ if (BUG(delay < 0))
+ delay = 0;
+
+ if (base_delay < 1)
+ base_delay = 1;
+
+ int low_bound=0, high_bound=INT_MAX;
+
+ next_random_exponential_delay_range(&low_bound, &high_bound,
+ delay, base_delay);
+
+ return crypto_rand_int_range(low_bound, high_bound);
+}
+
+/** Find the current delay for dls based on min_delay.
+ *
+ * This function sets dls->next_attempt_at based on now, and returns the delay.
+ * Helper for download_status_increment_failure and
+ * download_status_increment_attempt. */
+STATIC int
+download_status_schedule_get_delay(download_status_t *dls,
+ int min_delay,
+ time_t now)
+{
+ tor_assert(dls);
+ /* If we're using random exponential backoff, we do need min/max delay */
+ tor_assert(min_delay >= 0);
+
+ int delay = INT_MAX;
+ uint8_t dls_schedule_position = (dls->increment_on
+ == DL_SCHED_INCREMENT_ATTEMPT
+ ? dls->n_download_attempts
+ : dls->n_download_failures);
+
+ /* Check if we missed a reset somehow */
+ IF_BUG_ONCE(dls->last_backoff_position > dls_schedule_position) {
+ dls->last_backoff_position = 0;
+ dls->last_delay_used = 0;
+ }
+
+ if (dls_schedule_position > 0) {
+ delay = dls->last_delay_used;
+
+ while (dls->last_backoff_position < dls_schedule_position) {
+ /* Do one increment step */
+ delay = next_random_exponential_delay(delay, min_delay);
+ /* Update our position */
+ ++(dls->last_backoff_position);
+ }
+ } else {
+ /* If we're just starting out, use the minimum delay */
+ delay = min_delay;
+ }
+
+ /* Clamp it within min/max if we have them */
+ if (min_delay >= 0 && delay < min_delay) delay = min_delay;
+
+ /* Store it for next time */
+ dls->last_backoff_position = dls_schedule_position;
+ dls->last_delay_used = delay;
+
+ /* A negative delay makes no sense. Knowing that delay is
+ * non-negative allows us to safely do the wrapping check below. */
+ tor_assert(delay >= 0);
+
+ /* Avoid now+delay overflowing TIME_MAX, by comparing with a subtraction
+ * that won't overflow (since delay is non-negative). */
+ if (delay < INT_MAX && now <= TIME_MAX - delay) {
+ dls->next_attempt_at = now+delay;
+ } else {
+ dls->next_attempt_at = TIME_MAX;
+ }
+
+ return delay;
+}
+
+/* Log a debug message about item, which increments on increment_action, has
+ * incremented dls_n_download_increments times. The message varies based on
+ * was_schedule_incremented (if not, not_incremented_response is logged), and
+ * the values of increment, dls_next_attempt_at, and now.
+ * Helper for download_status_increment_failure and
+ * download_status_increment_attempt. */
+static void
+download_status_log_helper(const char *item, int was_schedule_incremented,
+ const char *increment_action,
+ const char *not_incremented_response,
+ uint8_t dls_n_download_increments, int increment,
+ time_t dls_next_attempt_at, time_t now)
+{
+ if (item) {
+ if (!was_schedule_incremented)
+ log_debug(LD_DIR, "%s %s %d time(s); I'll try again %s.",
+ item, increment_action, (int)dls_n_download_increments,
+ not_incremented_response);
+ else if (increment == 0)
+ log_debug(LD_DIR, "%s %s %d time(s); I'll try again immediately.",
+ item, increment_action, (int)dls_n_download_increments);
+ else if (dls_next_attempt_at < TIME_MAX)
+ log_debug(LD_DIR, "%s %s %d time(s); I'll try again in %d seconds.",
+ item, increment_action, (int)dls_n_download_increments,
+ (int)(dls_next_attempt_at-now));
+ else
+ log_debug(LD_DIR, "%s %s %d time(s); Giving up for a while.",
+ item, increment_action, (int)dls_n_download_increments);
+ }
+}
+
+/** Determine when a failed download attempt should be retried.
+ * Called when an attempt to download <b>dls</b> has failed with HTTP status
+ * <b>status_code</b>. Increment the failure count (if the code indicates a
+ * real failure, or if we're a server) and set <b>dls</b>-\>next_attempt_at to
+ * an appropriate time in the future and return it.
+ * If <b>dls->increment_on</b> is DL_SCHED_INCREMENT_ATTEMPT, increment the
+ * failure count, and return a time in the far future for the next attempt (to
+ * avoid an immediate retry). */
+time_t
+download_status_increment_failure(download_status_t *dls, int status_code,
+ const char *item, int server, time_t now)
+{
+ (void) status_code; // XXXX no longer used.
+ (void) server; // XXXX no longer used.
+ int increment = -1;
+ int min_delay = 0;
+
+ tor_assert(dls);
+
+ /* dls wasn't reset before it was used */
+ if (dls->next_attempt_at == 0) {
+ download_status_reset(dls);
+ }
+
+ /* count the failure */
+ if (dls->n_download_failures < IMPOSSIBLE_TO_DOWNLOAD-1) {
+ ++dls->n_download_failures;
+ }
+
+ if (dls->increment_on == DL_SCHED_INCREMENT_FAILURE) {
+ /* We don't find out that a failure-based schedule has attempted a
+ * connection until that connection fails.
+ * We'll never find out about successful connections, but this doesn't
+ * matter, because schedules are reset after a successful download.
+ */
+ if (dls->n_download_attempts < IMPOSSIBLE_TO_DOWNLOAD-1)
+ ++dls->n_download_attempts;
+
+ /* only return a failure retry time if this schedule increments on failures
+ */
+ min_delay = find_dl_min_delay(dls, get_options());
+ increment = download_status_schedule_get_delay(dls, min_delay, now);
+ }
+
+ download_status_log_helper(item, !dls->increment_on, "failed",
+ "concurrently", dls->n_download_failures,
+ increment,
+ download_status_get_next_attempt_at(dls),
+ now);
+
+ if (dls->increment_on == DL_SCHED_INCREMENT_ATTEMPT) {
+ /* stop this schedule retrying on failure, it will launch concurrent
+ * connections instead */
+ return TIME_MAX;
+ } else {
+ return download_status_get_next_attempt_at(dls);
+ }
+}
+
+/** Determine when the next download attempt should be made when using an
+ * attempt-based (potentially concurrent) download schedule.
+ * Called when an attempt to download <b>dls</b> is being initiated.
+ * Increment the attempt count and set <b>dls</b>-\>next_attempt_at to an
+ * appropriate time in the future and return it.
+ * If <b>dls->increment_on</b> is DL_SCHED_INCREMENT_FAILURE, don't increment
+ * the attempts, and return a time in the far future (to avoid launching a
+ * concurrent attempt). */
+time_t
+download_status_increment_attempt(download_status_t *dls, const char *item,
+ time_t now)
+{
+ int delay = -1;
+ int min_delay = 0;
+
+ tor_assert(dls);
+
+ /* dls wasn't reset before it was used */
+ if (dls->next_attempt_at == 0) {
+ download_status_reset(dls);
+ }
+
+ if (dls->increment_on == DL_SCHED_INCREMENT_FAILURE) {
+ /* this schedule should retry on failure, and not launch any concurrent
+ attempts */
+ log_warn(LD_BUG, "Tried to launch an attempt-based connection on a "
+ "failure-based schedule.");
+ return TIME_MAX;
+ }
+
+ if (dls->n_download_attempts < IMPOSSIBLE_TO_DOWNLOAD-1)
+ ++dls->n_download_attempts;
+
+ min_delay = find_dl_min_delay(dls, get_options());
+ delay = download_status_schedule_get_delay(dls, min_delay, now);
+
+ download_status_log_helper(item, dls->increment_on, "attempted",
+ "on failure", dls->n_download_attempts,
+ delay, download_status_get_next_attempt_at(dls),
+ now);
+
+ return download_status_get_next_attempt_at(dls);
+}
+
+static time_t
+download_status_get_initial_delay_from_now(const download_status_t *dls)
+{
+ /* We use constant initial delays, even in exponential backoff
+ * schedules. */
+ return time(NULL) + find_dl_min_delay(dls, get_options());
+}
+
+/** Reset <b>dls</b> so that it will be considered downloadable
+ * immediately, and/or to show that we don't need it anymore.
+ *
+ * Must be called to initialise a download schedule, otherwise the zeroth item
+ * in the schedule will never be used.
+ *
+ * (We find the zeroth element of the download schedule, and set
+ * next_attempt_at to be the appropriate offset from 'now'. In most
+ * cases this means setting it to 'now', so the item will be immediately
+ * downloadable; when using authorities with fallbacks, there is a few seconds'
+ * delay.) */
+void
+download_status_reset(download_status_t *dls)
+{
+ if (dls->n_download_failures == IMPOSSIBLE_TO_DOWNLOAD
+ || dls->n_download_attempts == IMPOSSIBLE_TO_DOWNLOAD)
+ return; /* Don't reset this. */
+
+ dls->n_download_failures = 0;
+ dls->n_download_attempts = 0;
+ dls->next_attempt_at = download_status_get_initial_delay_from_now(dls);
+ dls->last_backoff_position = 0;
+ dls->last_delay_used = 0;
+ /* Don't reset dls->want_authority or dls->increment_on */
+}
+
+/** Return true iff, as of <b>now</b>, the resource tracked by <b>dls</b> is
+ * ready to get its download reattempted. */
+int
+download_status_is_ready(download_status_t *dls, time_t now)
+{
+ /* dls wasn't reset before it was used */
+ if (dls->next_attempt_at == 0) {
+ download_status_reset(dls);
+ }
+
+ return download_status_get_next_attempt_at(dls) <= now;
+}
+
+/** Mark <b>dl</b> as never downloadable. */
+void
+download_status_mark_impossible(download_status_t *dl)
+{
+ dl->n_download_failures = IMPOSSIBLE_TO_DOWNLOAD;
+ dl->n_download_attempts = IMPOSSIBLE_TO_DOWNLOAD;
+}
+
+/** Return the number of failures on <b>dls</b> since the last success (if
+ * any). */
+int
+download_status_get_n_failures(const download_status_t *dls)
+{
+ return dls->n_download_failures;
+}
+
+/** Return the number of attempts to download <b>dls</b> since the last success
+ * (if any). This can differ from download_status_get_n_failures() due to
+ * outstanding concurrent attempts. */
+int
+download_status_get_n_attempts(const download_status_t *dls)
+{
+ return dls->n_download_attempts;
+}
+
+/** Return the next time to attempt to download <b>dls</b>. */
+time_t
+download_status_get_next_attempt_at(const download_status_t *dls)
+{
+ /* dls wasn't reset before it was used */
+ if (dls->next_attempt_at == 0) {
+ /* so give the answer we would have given if it had been */
+ return download_status_get_initial_delay_from_now(dls);
+ }
+
+ return dls->next_attempt_at;
+}
+
+/** Called when one or more routerdesc (or extrainfo, if <b>was_extrainfo</b>)
+ * fetches have failed (with uppercase fingerprints listed in <b>failed</b>,
+ * either as descriptor digests or as identity digests based on
+ * <b>was_descriptor_digests</b>).
+ */
+static void
+dir_routerdesc_download_failed(smartlist_t *failed, int status_code,
+ int router_purpose,
+ int was_extrainfo, int was_descriptor_digests)
+{
+ char digest[DIGEST_LEN];
+ time_t now = time(NULL);
+ int server = directory_fetches_from_authorities(get_options());
+ if (!was_descriptor_digests) {
+ if (router_purpose == ROUTER_PURPOSE_BRIDGE) {
+ tor_assert(!was_extrainfo);
+ connection_dir_retry_bridges(failed);
+ }
+ return; /* FFFF should implement for other-than-router-purpose someday */
+ }
+ SMARTLIST_FOREACH_BEGIN(failed, const char *, cp) {
+ download_status_t *dls = NULL;
+ if (base16_decode(digest, DIGEST_LEN, cp, strlen(cp)) != DIGEST_LEN) {
+ log_warn(LD_BUG, "Malformed fingerprint in list: %s", escaped(cp));
+ continue;
+ }
+ if (was_extrainfo) {
+ signed_descriptor_t *sd =
+ router_get_by_extrainfo_digest(digest);
+ if (sd)
+ dls = &sd->ei_dl_status;
+ } else {
+ dls = router_get_dl_status_by_descriptor_digest(digest);
+ }
+ if (!dls)
+ continue;
+ download_status_increment_failure(dls, status_code, cp, server, now);
+ } SMARTLIST_FOREACH_END(cp);
+
+ /* No need to relaunch descriptor downloads here: we already do it
+ * every 10 or 60 seconds (FOO_DESCRIPTOR_RETRY_INTERVAL) in main.c. */
+}
+
+/** Called when a connection to download microdescriptors from relay with
+ * <b>dir_id</b> has failed in whole or in part. <b>failed</b> is a list
+ * of every microdesc digest we didn't get. <b>status_code</b> is the http
+ * status code we received. Reschedule the microdesc downloads as
+ * appropriate. */
+static void
+dir_microdesc_download_failed(smartlist_t *failed,
+ int status_code, const char *dir_id)
+{
+ networkstatus_t *consensus
+ = networkstatus_get_latest_consensus_by_flavor(FLAV_MICRODESC);
+ routerstatus_t *rs;
+ download_status_t *dls;
+ time_t now = time(NULL);
+ int server = directory_fetches_from_authorities(get_options());
+
+ if (! consensus)
+ return;
+
+ /* We failed to fetch a microdescriptor from 'dir_id', note it down
+ * so that we don't try the same relay next time... */
+ microdesc_note_outdated_dirserver(dir_id);
+
+ SMARTLIST_FOREACH_BEGIN(failed, const char *, d) {
+ rs = router_get_mutable_consensus_status_by_descriptor_digest(consensus,d);
+ if (!rs)
+ continue;
+ dls = &rs->dl_status;
+
+ { /* Increment the failure count for this md fetch */
+ char buf[BASE64_DIGEST256_LEN+1];
+ digest256_to_base64(buf, d);
+ log_info(LD_DIR, "Failed to download md %s from %s",
+ buf, hex_str(dir_id, DIGEST_LEN));
+ download_status_increment_failure(dls, status_code, buf,
+ server, now);
+ }
+ } SMARTLIST_FOREACH_END(d);
+}
+
+/** Helper. Compare two fp_pair_t objects, and return negative, 0, or
+ * positive as appropriate. */
+static int
+compare_pairs_(const void **a, const void **b)
+{
+ const fp_pair_t *fp1 = *a, *fp2 = *b;
+ int r;
+ if ((r = fast_memcmp(fp1->first, fp2->first, DIGEST_LEN)))
+ return r;
+ else
+ return fast_memcmp(fp1->second, fp2->second, DIGEST_LEN);
+}
+
+/** Divide a string <b>res</b> of the form FP1-FP2+FP3-FP4...[.z], where each
+ * FP is a hex-encoded fingerprint, into a sequence of distinct sorted
+ * fp_pair_t. Skip malformed pairs. On success, return 0 and add those
+ * fp_pair_t into <b>pairs_out</b>. On failure, return -1. */
+int
+dir_split_resource_into_fingerprint_pairs(const char *res,
+ smartlist_t *pairs_out)
+{
+ smartlist_t *pairs_tmp = smartlist_new();
+ smartlist_t *pairs_result = smartlist_new();
+
+ smartlist_split_string(pairs_tmp, res, "+", 0, 0);
+ if (smartlist_len(pairs_tmp)) {
+ char *last = smartlist_get(pairs_tmp,smartlist_len(pairs_tmp)-1);
+ size_t last_len = strlen(last);
+ if (last_len > 2 && !strcmp(last+last_len-2, ".z")) {
+ last[last_len-2] = '\0';
+ }
+ }
+ SMARTLIST_FOREACH_BEGIN(pairs_tmp, char *, cp) {
+ if (strlen(cp) != HEX_DIGEST_LEN*2+1) {
+ log_info(LD_DIR,
+ "Skipping digest pair %s with non-standard length.", escaped(cp));
+ } else if (cp[HEX_DIGEST_LEN] != '-') {
+ log_info(LD_DIR,
+ "Skipping digest pair %s with missing dash.", escaped(cp));
+ } else {
+ fp_pair_t pair;
+ if (base16_decode(pair.first, DIGEST_LEN,
+ cp, HEX_DIGEST_LEN) != DIGEST_LEN ||
+ base16_decode(pair.second,DIGEST_LEN,
+ cp+HEX_DIGEST_LEN+1, HEX_DIGEST_LEN) != DIGEST_LEN) {
+ log_info(LD_DIR, "Skipping non-decodable digest pair %s", escaped(cp));
+ } else {
+ smartlist_add(pairs_result, tor_memdup(&pair, sizeof(pair)));
+ }
+ }
+ tor_free(cp);
+ } SMARTLIST_FOREACH_END(cp);
+ smartlist_free(pairs_tmp);
+
+ /* Uniq-and-sort */
+ smartlist_sort(pairs_result, compare_pairs_);
+ smartlist_uniq(pairs_result, compare_pairs_, tor_free_);
+
+ smartlist_add_all(pairs_out, pairs_result);
+ smartlist_free(pairs_result);
+ return 0;
+}
+
+/** Given a directory <b>resource</b> request, containing zero
+ * or more strings separated by plus signs, followed optionally by ".z", store
+ * the strings, in order, into <b>fp_out</b>. If <b>compressed_out</b> is
+ * non-NULL, set it to 1 if the resource ends in ".z", else set it to 0.
+ *
+ * If (flags & DSR_HEX), then delete all elements that aren't hex digests, and
+ * decode the rest. If (flags & DSR_BASE64), then use "-" rather than "+" as
+ * a separator, delete all the elements that aren't base64-encoded digests,
+ * and decode the rest. If (flags & DSR_DIGEST256), these digests should be
+ * 256 bits long; else they should be 160.
+ *
+ * If (flags & DSR_SORT_UNIQ), 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 flags)
+{
+ const int decode_hex = flags & DSR_HEX;
+ const int decode_base64 = flags & DSR_BASE64;
+ const int digests_are_256 = flags & DSR_DIGEST256;
+ const int sort_uniq = flags & DSR_SORT_UNIQ;
+
+ const int digest_len = digests_are_256 ? DIGEST256_LEN : DIGEST_LEN;
+ const int hex_digest_len = digests_are_256 ?
+ HEX_DIGEST256_LEN : HEX_DIGEST_LEN;
+ const int base64_digest_len = digests_are_256 ?
+ BASE64_DIGEST256_LEN : BASE64_DIGEST_LEN;
+ smartlist_t *fp_tmp = smartlist_new();
+
+ tor_assert(!(decode_hex && decode_base64));
+ tor_assert(fp_out);
+
+ smartlist_split_string(fp_tmp, resource, decode_base64?"-":"+", 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 || decode_base64) {
+ const size_t encoded_len = decode_hex ? hex_digest_len : base64_digest_len;
+ int i;
+ char *cp, *d = NULL;
+ for (i = 0; i < smartlist_len(fp_tmp); ++i) {
+ cp = smartlist_get(fp_tmp, i);
+ if (strlen(cp) != encoded_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 (decode_hex ?
+ (base16_decode(d, digest_len, cp, hex_digest_len) != digest_len) :
+ (base64_decode(d, digest_len, cp, base64_digest_len)
+ != digest_len)) {
+ 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) {
+ if (decode_hex || decode_base64) {
+ if (digests_are_256) {
+ smartlist_sort_digests256(fp_tmp);
+ smartlist_uniq_digests256(fp_tmp);
+ } else {
+ smartlist_sort_digests(fp_tmp);
+ smartlist_uniq_digests(fp_tmp);
+ }
+ } else {
+ smartlist_sort_strings(fp_tmp);
+ smartlist_uniq_strings(fp_tmp);
+ }
+ }
+ smartlist_add_all(fp_out, fp_tmp);
+ smartlist_free(fp_tmp);
+ return 0;
+}
+
+/** As dir_split_resource_into_fingerprints, but instead fills
+ * <b>spool_out</b> with a list of spoolable_resource_t for the resource
+ * identified through <b>source</b>. */
+int
+dir_split_resource_into_spoolable(const char *resource,
+ dir_spool_source_t source,
+ smartlist_t *spool_out,
+ int *compressed_out,
+ int flags)
+{
+ smartlist_t *fingerprints = smartlist_new();
+
+ tor_assert(flags & (DSR_HEX|DSR_BASE64));
+ const size_t digest_len =
+ (flags & DSR_DIGEST256) ? DIGEST256_LEN : DIGEST_LEN;
+
+ int r = dir_split_resource_into_fingerprints(resource, fingerprints,
+ compressed_out, flags);
+ /* This is not a very efficient implementation XXXX */
+ SMARTLIST_FOREACH_BEGIN(fingerprints, uint8_t *, digest) {
+ spooled_resource_t *spooled =
+ spooled_resource_new(source, digest, digest_len);
+ if (spooled)
+ smartlist_add(spool_out, spooled);
+ tor_free(digest);
+ } SMARTLIST_FOREACH_END(digest);
+
+ smartlist_free(fingerprints);
+ return r;
+}
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