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- /* Copyright (c) 2016-2017, The Tor Project, Inc. */
- /* See LICENSE for licensing information */
- /**
- * \file hs_service.c
- * \brief Implement next generation hidden service functionality
- **/
- #define HS_SERVICE_PRIVATE
- #include "or.h"
- #include "circuitlist.h"
- #include "config.h"
- #include "relay.h"
- #include "rendservice.h"
- #include "router.h"
- #include "routerkeys.h"
- #include "hs_common.h"
- #include "hs_config.h"
- #include "hs_intropoint.h"
- #include "hs_service.h"
- #include "hs/cell_establish_intro.h"
- #include "hs/cell_common.h"
- /* Onion service directory file names. */
- static const char *fname_keyfile_prefix = "hs_ed25519";
- static const char *fname_hostname = "hostname";
- static const char *address_tld = "onion";
- /* Staging list of service object. When configuring service, we add them to
- * this list considered a staging area and they will get added to our global
- * map once the keys have been loaded. These two steps are seperated because
- * loading keys requires that we are an actual running tor process. */
- static smartlist_t *hs_service_staging_list;
- /* Helper: Function to compare two objects in the service map. Return 1 if the
- * two service have the same master public identity key. */
- static inline int
- hs_service_ht_eq(const hs_service_t *first, const hs_service_t *second)
- {
- tor_assert(first);
- tor_assert(second);
- /* Simple key compare. */
- return ed25519_pubkey_eq(&first->keys.identity_pk,
- &second->keys.identity_pk);
- }
- /* Helper: Function for the service hash table code below. The key used is the
- * master public identity key which is ultimately the onion address. */
- static inline unsigned int
- hs_service_ht_hash(const hs_service_t *service)
- {
- tor_assert(service);
- return (unsigned int) siphash24g(service->keys.identity_pk.pubkey,
- sizeof(service->keys.identity_pk.pubkey));
- }
- /* This is _the_ global hash map of hidden services which indexed the service
- * contained in it by master public identity key which is roughly the onion
- * address of the service. */
- static struct hs_service_ht *hs_service_map;
- /* Register the service hash table. */
- HT_PROTOTYPE(hs_service_ht, /* Name of hashtable. */
- hs_service_t, /* Object contained in the map. */
- hs_service_node, /* The name of the HT_ENTRY member. */
- hs_service_ht_hash, /* Hashing function. */
- hs_service_ht_eq) /* Compare function for objects. */
- HT_GENERATE2(hs_service_ht, hs_service_t, hs_service_node,
- hs_service_ht_hash, hs_service_ht_eq,
- 0.6, tor_reallocarray, tor_free_)
- /* Query the given service map with a public key and return a service object
- * if found else NULL. It is also possible to set a directory path in the
- * search query. If pk is NULL, then it will be set to zero indicating the
- * hash table to compare the directory path instead. */
- STATIC hs_service_t *
- find_service(hs_service_ht *map, const ed25519_public_key_t *pk)
- {
- hs_service_t dummy_service;
- tor_assert(map);
- tor_assert(pk);
- memset(&dummy_service, 0, sizeof(dummy_service));
- ed25519_pubkey_copy(&dummy_service.keys.identity_pk, pk);
- return HT_FIND(hs_service_ht, map, &dummy_service);
- }
- /* Register the given service in the given map. If the service already exists
- * in the map, -1 is returned. On success, 0 is returned and the service
- * ownership has been transfered to the global map. */
- STATIC int
- register_service(hs_service_ht *map, hs_service_t *service)
- {
- tor_assert(map);
- tor_assert(service);
- tor_assert(!ed25519_public_key_is_zero(&service->keys.identity_pk));
- if (find_service(map, &service->keys.identity_pk)) {
- /* Existing service with the same key. Do not register it. */
- return -1;
- }
- /* Taking ownership of the object at this point. */
- HT_INSERT(hs_service_ht, map, service);
- return 0;
- }
- /* Remove a given service from the given map. If service is NULL or the
- * service key is unset, return gracefully. */
- STATIC void
- remove_service(hs_service_ht *map, hs_service_t *service)
- {
- hs_service_t *elm;
- tor_assert(map);
- /* Ignore if no service or key is zero. */
- if (BUG(service == NULL) ||
- BUG(ed25519_public_key_is_zero(&service->keys.identity_pk))) {
- return;
- }
- elm = HT_REMOVE(hs_service_ht, map, service);
- if (elm) {
- tor_assert(elm == service);
- } else {
- log_warn(LD_BUG, "Could not find service in the global map "
- "while removing service %s",
- escaped(service->config.directory_path));
- }
- }
- /* Set the default values for a service configuration object <b>c</b>. */
- static void
- set_service_default_config(hs_service_config_t *c,
- const or_options_t *options)
- {
- tor_assert(c);
- c->ports = smartlist_new();
- c->directory_path = NULL;
- c->descriptor_post_period = options->RendPostPeriod;
- c->max_streams_per_rdv_circuit = 0;
- c->max_streams_close_circuit = 0;
- c->num_intro_points = NUM_INTRO_POINTS_DEFAULT;
- c->allow_unknown_ports = 0;
- c->is_single_onion = 0;
- c->dir_group_readable = 0;
- c->is_ephemeral = 0;
- }
- /* From a service configuration object config, clear everything from it
- * meaning free allocated pointers and reset the values. */
- static void
- service_clear_config(hs_service_config_t *config)
- {
- if (config == NULL) {
- return;
- }
- tor_free(config->directory_path);
- if (config->ports) {
- SMARTLIST_FOREACH(config->ports, rend_service_port_config_t *, p,
- rend_service_port_config_free(p););
- smartlist_free(config->ports);
- }
- memset(config, 0, sizeof(*config));
- }
- /* Helper: Function that needs to return 1 for the HT for each loop which
- * frees every service in an hash map. */
- static int
- ht_free_service_(struct hs_service_t *service, void *data)
- {
- (void) data;
- hs_service_free(service);
- /* This function MUST return 1 so the given object is then removed from the
- * service map leading to this free of the object being safe. */
- return 1;
- }
- /* Free every service that can be found in the global map. Once done, clear
- * and free the global map. */
- static void
- service_free_all(void)
- {
- if (hs_service_map) {
- /* The free helper function returns 1 so this is safe. */
- hs_service_ht_HT_FOREACH_FN(hs_service_map, ht_free_service_, NULL);
- HT_CLEAR(hs_service_ht, hs_service_map);
- tor_free(hs_service_map);
- hs_service_map = NULL;
- }
- if (hs_service_staging_list) {
- /* Cleanup staging list. */
- SMARTLIST_FOREACH(hs_service_staging_list, hs_service_t *, s,
- hs_service_free(s));
- smartlist_free(hs_service_staging_list);
- hs_service_staging_list = NULL;
- }
- }
- /* Close all rendezvous circuits for the given service. */
- static void
- close_service_rp_circuits(hs_service_t *service)
- {
- tor_assert(service);
- /* XXX: To implement. */
- return;
- }
- /* Close the circuit(s) for the given map of introduction points. */
- static void
- close_intro_circuits(hs_service_intropoints_t *intro_points)
- {
- tor_assert(intro_points);
- DIGEST256MAP_FOREACH(intro_points->map, key,
- const hs_service_intro_point_t *, ip) {
- origin_circuit_t *ocirc =
- hs_circuitmap_get_intro_circ_v3_service_side(
- &ip->auth_key_kp.pubkey);
- if (ocirc) {
- hs_circuitmap_remove_circuit(TO_CIRCUIT(ocirc));
- /* Reason is FINISHED because service has been removed and thus the
- * circuit is considered old/uneeded. */
- circuit_mark_for_close(TO_CIRCUIT(ocirc), END_CIRC_REASON_FINISHED);
- }
- } DIGEST256MAP_FOREACH_END;
- }
- /* Close all introduction circuits for the given service. */
- static void
- close_service_intro_circuits(hs_service_t *service)
- {
- tor_assert(service);
- if (service->desc_current) {
- close_intro_circuits(&service->desc_current->intro_points);
- }
- if (service->desc_next) {
- close_intro_circuits(&service->desc_next->intro_points);
- }
- }
- /* Close any circuits related to the given service. */
- static void
- close_service_circuits(hs_service_t *service)
- {
- tor_assert(service);
- /* Only support for version >= 3. */
- if (BUG(service->config.version < HS_VERSION_THREE)) {
- return;
- }
- /* Close intro points. */
- close_service_intro_circuits(service);
- /* Close rendezvous points. */
- close_service_rp_circuits(service);
- }
- /* Move introduction points from the src descriptor to the dst descriptor. The
- * destination service intropoints are wiped out if any before moving. */
- static void
- move_descriptor_intro_points(hs_service_descriptor_t *src,
- hs_service_descriptor_t *dst)
- {
- tor_assert(src);
- tor_assert(dst);
- /* XXX: Free dst introduction points. */
- dst->intro_points.map = src->intro_points.map;
- /* Nullify the source. */
- src->intro_points.map = NULL;
- }
- /* Move introduction points from the src service to the dst service. The
- * destination service intropoints are wiped out if any before moving. */
- static void
- move_intro_points(hs_service_t *src, hs_service_t *dst)
- {
- tor_assert(src);
- tor_assert(dst);
- /* Cleanup destination. */
- if (src->desc_current && dst->desc_current) {
- move_descriptor_intro_points(src->desc_current, dst->desc_current);
- }
- if (src->desc_next && dst->desc_next) {
- move_descriptor_intro_points(src->desc_next, dst->desc_next);
- }
- }
- /* Move every ephemeral services from the src service map to the dst service
- * map. It is possible that a service can't be register to the dst map which
- * won't stop the process of moving them all but will trigger a log warn. */
- static void
- move_ephemeral_services(hs_service_ht *src, hs_service_ht *dst)
- {
- hs_service_t **iter, **next;
- tor_assert(src);
- tor_assert(dst);
- /* Iterate over the map to find ephemeral service and move them to the other
- * map. We loop using this method to have a safe removal process. */
- for (iter = HT_START(hs_service_ht, src); iter != NULL; iter = next) {
- hs_service_t *s = *iter;
- if (!s->config.is_ephemeral) {
- /* Yeah, we are in a very manual loop :). */
- next = HT_NEXT(hs_service_ht, src, iter);
- continue;
- }
- /* Remove service from map and then register to it to the other map.
- * Reminder that "*iter" and "s" are the same thing. */
- next = HT_NEXT_RMV(hs_service_ht, src, iter);
- if (register_service(dst, s) < 0) {
- log_warn(LD_BUG, "Ephemeral service key is already being used. "
- "Skipping.");
- }
- }
- }
- /* Return a const string of the directory path escaped. If this is an
- * ephemeral service, it returns "[EPHEMERAL]". This can only be called from
- * the main thread because escaped() uses a static variable. */
- static const char *
- service_escaped_dir(const hs_service_t *s)
- {
- return (s->config.is_ephemeral) ? "[EPHEMERAL]" :
- escaped(s->config.directory_path);
- }
- /* Register services that are in the staging list. Once this function returns,
- * the global service map will be set with the right content and all non
- * surviving services will be cleaned up. */
- static void
- register_all_services(void)
- {
- struct hs_service_ht *new_service_map;
- hs_service_t *s, **iter;
- tor_assert(hs_service_staging_list);
- /* We'll save us some allocation and computing time. */
- if (smartlist_len(hs_service_staging_list) == 0) {
- return;
- }
- /* Allocate a new map that will replace the current one. */
- new_service_map = tor_malloc_zero(sizeof(*new_service_map));
- HT_INIT(hs_service_ht, new_service_map);
- /* First step is to transfer all ephemeral services from the current global
- * map to the new one we are constructing. We do not prune ephemeral
- * services as the only way to kill them is by deleting it from the control
- * port or stopping the tor daemon. */
- move_ephemeral_services(hs_service_map, new_service_map);
- SMARTLIST_FOREACH_BEGIN(hs_service_staging_list, hs_service_t *, snew) {
- /* Check if that service is already in our global map and if so, we'll
- * transfer the intro points to it. */
- s = find_service(hs_service_map, &snew->keys.identity_pk);
- if (s) {
- /* Pass ownership of intro points from s (the current service) to snew
- * (the newly configured one). */
- move_intro_points(s, snew);
- /* Remove the service from the global map because after this, we need to
- * go over the remaining service in that map that aren't surviving the
- * reload to close their circuits. */
- remove_service(hs_service_map, s);
- }
- /* Great, this service is now ready to be added to our new map. */
- if (BUG(register_service(new_service_map, snew) < 0)) {
- /* This should never happen because prior to registration, we validate
- * every service against the entire set. Not being able to register a
- * service means we failed to validate correctly. In that case, don't
- * break tor and ignore the service but tell user. */
- log_warn(LD_BUG, "Unable to register service with directory %s",
- service_escaped_dir(snew));
- SMARTLIST_DEL_CURRENT(hs_service_staging_list, snew);
- hs_service_free(snew);
- }
- } SMARTLIST_FOREACH_END(snew);
- /* Close any circuits associated with the non surviving services. Every
- * service in the current global map are roaming. */
- HT_FOREACH(iter, hs_service_ht, hs_service_map) {
- close_service_circuits(*iter);
- }
- /* Time to make the switch. We'll clear the staging list because its content
- * has now changed ownership to the map. */
- smartlist_clear(hs_service_staging_list);
- service_free_all();
- hs_service_map = new_service_map;
- }
- /* Write the onion address of a given service to the given filename fname_ in
- * the service directory. Return 0 on success else -1 on error. */
- static int
- write_address_to_file(const hs_service_t *service, const char *fname_)
- {
- int ret = -1;
- char *fname = NULL;
- /* Length of an address plus the sizeof the address tld (onion) which counts
- * the NUL terminated byte so we keep it for the "." and the newline. */
- char buf[HS_SERVICE_ADDR_LEN_BASE32 + sizeof(address_tld) + 1];
- tor_assert(service);
- tor_assert(fname_);
- /* Construct the full address with the onion tld and write the hostname file
- * to disk. */
- tor_snprintf(buf, sizeof(buf), "%s.%s\n", service->onion_address,
- address_tld);
- /* Notice here that we use the given "fname_". */
- fname = hs_path_from_filename(service->config.directory_path, fname_);
- if (write_str_to_file(fname, buf, 0) < 0) {
- log_warn(LD_REND, "Could not write onion address to hostname file %s",
- escaped(fname));
- goto end;
- }
- #ifndef _WIN32
- if (service->config.dir_group_readable) {
- /* Mode to 0640. */
- if (chmod(fname, S_IRUSR | S_IWUSR | S_IRGRP) < 0) {
- log_warn(LD_FS, "Unable to make onion service hostname file %s "
- "group-readable.", escaped(fname));
- }
- }
- #endif /* _WIN32 */
- /* Success. */
- ret = 0;
- end:
- tor_free(fname);
- return ret;
- }
- /* Load and/or generate private keys for the given service. On success, the
- * hostname file will be written to disk along with the master private key iff
- * the service is not configured for offline keys. Return 0 on success else -1
- * on failure. */
- static int
- load_service_keys(hs_service_t *service)
- {
- int ret = -1;
- char *fname = NULL;
- ed25519_keypair_t *kp;
- const hs_service_config_t *config;
- tor_assert(service);
- config = &service->config;
- /* Create and fix permission on service directory. We are about to write
- * files to that directory so make sure it exists and has the right
- * permissions. We do this here because at this stage we know that Tor is
- * actually running and the service we have has been validated. */
- if (BUG(hs_check_service_private_dir(get_options()->User,
- config->directory_path,
- config->dir_group_readable, 1) < 0)) {
- goto end;
- }
- /* Try to load the keys from file or generate it if not found. */
- fname = hs_path_from_filename(config->directory_path, fname_keyfile_prefix);
- /* Don't ask for key creation, we want to know if we were able to load it or
- * we had to generate it. Better logging! */
- kp = ed_key_init_from_file(fname, 0, LOG_INFO, NULL, 0, 0, 0, NULL);
- if (!kp) {
- log_info(LD_REND, "Unable to load keys from %s. Generating it...", fname);
- /* We'll now try to generate the keys and for it we want the strongest
- * randomness for it. The keypair will be written in different files. */
- uint32_t key_flags = INIT_ED_KEY_CREATE | INIT_ED_KEY_EXTRA_STRONG |
- INIT_ED_KEY_SPLIT;
- kp = ed_key_init_from_file(fname, key_flags, LOG_WARN, NULL, 0, 0, 0,
- NULL);
- if (!kp) {
- log_warn(LD_REND, "Unable to generate keys and save in %s.", fname);
- goto end;
- }
- }
- /* Copy loaded or generated keys to service object. */
- ed25519_pubkey_copy(&service->keys.identity_pk, &kp->pubkey);
- memcpy(&service->keys.identity_sk, &kp->seckey,
- sizeof(service->keys.identity_sk));
- /* This does a proper memory wipe. */
- ed25519_keypair_free(kp);
- /* Build onion address from the newly loaded keys. */
- tor_assert(service->config.version <= UINT8_MAX);
- hs_build_address(&service->keys.identity_pk,
- (uint8_t) service->config.version,
- service->onion_address);
- /* Write onion address to hostname file. */
- if (write_address_to_file(service, fname_hostname) < 0) {
- goto end;
- }
- /* Succes. */
- ret = 0;
- end:
- tor_free(fname);
- return ret;
- }
- /* Load and/or generate keys for all onion services including the client
- * authorization if any. Return 0 on success, -1 on failure. */
- int
- hs_service_load_all_keys(void)
- {
- /* Load v2 service keys if we have v2. */
- if (num_rend_services() != 0) {
- if (rend_service_load_all_keys(NULL) < 0) {
- goto err;
- }
- }
- /* Load or/and generate them for v3+. */
- SMARTLIST_FOREACH_BEGIN(hs_service_staging_list, hs_service_t *, service) {
- /* Ignore ephemeral service, they already have their keys set. */
- if (service->config.is_ephemeral) {
- continue;
- }
- log_info(LD_REND, "Loading v3 onion service keys from %s",
- service_escaped_dir(service));
- if (load_service_keys(service) < 0) {
- goto err;
- }
- /* XXX: Load/Generate client authorization keys. (#20700) */
- } SMARTLIST_FOREACH_END(service);
- /* Final step, the staging list contains service in a quiescent state that
- * is ready to be used. Register them to the global map. Once this is over,
- * the staging list will be cleaned up. */
- register_all_services();
- /* All keys have been loaded successfully. */
- return 0;
- err:
- return -1;
- }
- /* Put all service object in the given service list. After this, the caller
- * looses ownership of every elements in the list and responsible to free the
- * list pointer. */
- void
- hs_service_stage_services(const smartlist_t *service_list)
- {
- tor_assert(service_list);
- /* This list is freed at registration time but this function can be called
- * multiple time. */
- if (hs_service_staging_list == NULL) {
- hs_service_staging_list = smartlist_new();
- }
- /* Add all service object to our staging list. Caller is responsible for
- * freeing the service_list. */
- smartlist_add_all(hs_service_staging_list, service_list);
- }
- /* Allocate and initilize a service object. The service configuration will
- * contain the default values. Return the newly allocated object pointer. This
- * function can't fail. */
- hs_service_t *
- hs_service_new(const or_options_t *options)
- {
- hs_service_t *service = tor_malloc_zero(sizeof(hs_service_t));
- /* Set default configuration value. */
- set_service_default_config(&service->config, options);
- /* Set the default service version. */
- service->config.version = HS_SERVICE_DEFAULT_VERSION;
- return service;
- }
- /* Free the given <b>service</b> object and all its content. This function
- * also takes care of wiping service keys from memory. It is safe to pass a
- * NULL pointer. */
- void
- hs_service_free(hs_service_t *service)
- {
- if (service == NULL) {
- return;
- }
- /* Free descriptors. */
- if (service->desc_current) {
- hs_descriptor_free(service->desc_current->desc);
- /* Wipe keys. */
- memwipe(&service->desc_current->signing_kp, 0,
- sizeof(service->desc_current->signing_kp));
- memwipe(&service->desc_current->blinded_kp, 0,
- sizeof(service->desc_current->blinded_kp));
- /* XXX: Free intro points. */
- tor_free(service->desc_current);
- }
- if (service->desc_next) {
- hs_descriptor_free(service->desc_next->desc);
- /* Wipe keys. */
- memwipe(&service->desc_next->signing_kp, 0,
- sizeof(service->desc_next->signing_kp));
- memwipe(&service->desc_next->blinded_kp, 0,
- sizeof(service->desc_next->blinded_kp));
- /* XXX: Free intro points. */
- tor_free(service->desc_next);
- }
- /* Free service configuration. */
- service_clear_config(&service->config);
- /* Wipe service keys. */
- memwipe(&service->keys.identity_sk, 0, sizeof(service->keys.identity_sk));
- tor_free(service);
- }
- /* Initialize the service HS subsystem. */
- void
- hs_service_init(void)
- {
- /* Should never be called twice. */
- tor_assert(!hs_service_map);
- tor_assert(!hs_service_staging_list);
- /* v2 specific. */
- rend_service_init();
- hs_service_map = tor_malloc_zero(sizeof(struct hs_service_ht));
- HT_INIT(hs_service_ht, hs_service_map);
- hs_service_staging_list = smartlist_new();
- }
- /* Release all global storage of the hidden service subsystem. */
- void
- hs_service_free_all(void)
- {
- rend_service_free_all();
- service_free_all();
- }
- /* XXX We don't currently use these functions, apart from generating unittest
- data. When we start implementing the service-side support for prop224 we
- should revisit these functions and use them. */
- /** Given an ESTABLISH_INTRO <b>cell</b>, encode it and place its payload in
- * <b>buf_out</b> which has size <b>buf_out_len</b>. Return the number of
- * bytes written, or a negative integer if there was an error. */
- ssize_t
- get_establish_intro_payload(uint8_t *buf_out, size_t buf_out_len,
- const trn_cell_establish_intro_t *cell)
- {
- ssize_t bytes_used = 0;
- if (buf_out_len < RELAY_PAYLOAD_SIZE) {
- return -1;
- }
- bytes_used = trn_cell_establish_intro_encode(buf_out, buf_out_len,
- cell);
- return bytes_used;
- }
- /* Set the cell extensions of <b>cell</b>. */
- static void
- set_trn_cell_extensions(trn_cell_establish_intro_t *cell)
- {
- trn_cell_extension_t *trn_cell_extensions = trn_cell_extension_new();
- /* For now, we don't use extensions at all. */
- trn_cell_extensions->num = 0; /* It's already zeroed, but be explicit. */
- trn_cell_establish_intro_set_extensions(cell, trn_cell_extensions);
- }
- /** Given the circuit handshake info in <b>circuit_key_material</b>, create and
- * return an ESTABLISH_INTRO cell. Return NULL if something went wrong. The
- * returned cell is allocated on the heap and it's the responsibility of the
- * caller to free it. */
- trn_cell_establish_intro_t *
- generate_establish_intro_cell(const uint8_t *circuit_key_material,
- size_t circuit_key_material_len)
- {
- trn_cell_establish_intro_t *cell = NULL;
- ssize_t encoded_len;
- log_warn(LD_GENERAL,
- "Generating ESTABLISH_INTRO cell (key_material_len: %u)",
- (unsigned) circuit_key_material_len);
- /* Generate short-term keypair for use in ESTABLISH_INTRO */
- ed25519_keypair_t key_struct;
- if (ed25519_keypair_generate(&key_struct, 0) < 0) {
- goto err;
- }
- cell = trn_cell_establish_intro_new();
- /* Set AUTH_KEY_TYPE: 2 means ed25519 */
- trn_cell_establish_intro_set_auth_key_type(cell,
- HS_INTRO_AUTH_KEY_TYPE_ED25519);
- /* Set AUTH_KEY_LEN field */
- /* Must also set byte-length of AUTH_KEY to match */
- int auth_key_len = ED25519_PUBKEY_LEN;
- trn_cell_establish_intro_set_auth_key_len(cell, auth_key_len);
- trn_cell_establish_intro_setlen_auth_key(cell, auth_key_len);
- /* Set AUTH_KEY field */
- uint8_t *auth_key_ptr = trn_cell_establish_intro_getarray_auth_key(cell);
- memcpy(auth_key_ptr, key_struct.pubkey.pubkey, auth_key_len);
- /* No cell extensions needed */
- set_trn_cell_extensions(cell);
- /* Set signature size.
- We need to do this up here, because _encode() needs it and we need to call
- _encode() to calculate the MAC and signature.
- */
- int sig_len = ED25519_SIG_LEN;
- trn_cell_establish_intro_set_sig_len(cell, sig_len);
- trn_cell_establish_intro_setlen_sig(cell, sig_len);
- /* XXX How to make this process easier and nicer? */
- /* Calculate the cell MAC (aka HANDSHAKE_AUTH). */
- {
- /* To calculate HANDSHAKE_AUTH, we dump the cell in bytes, and then derive
- the MAC from it. */
- uint8_t cell_bytes_tmp[RELAY_PAYLOAD_SIZE] = {0};
- uint8_t mac[TRUNNEL_SHA3_256_LEN];
- encoded_len = trn_cell_establish_intro_encode(cell_bytes_tmp,
- sizeof(cell_bytes_tmp),
- cell);
- if (encoded_len < 0) {
- log_warn(LD_OR, "Unable to pre-encode ESTABLISH_INTRO cell.");
- goto err;
- }
- /* sanity check */
- tor_assert(encoded_len > ED25519_SIG_LEN + 2 + TRUNNEL_SHA3_256_LEN);
- /* Calculate MAC of all fields before HANDSHAKE_AUTH */
- crypto_mac_sha3_256(mac, sizeof(mac),
- circuit_key_material, circuit_key_material_len,
- cell_bytes_tmp,
- encoded_len -
- (ED25519_SIG_LEN + 2 + TRUNNEL_SHA3_256_LEN));
- /* Write the MAC to the cell */
- uint8_t *handshake_ptr =
- trn_cell_establish_intro_getarray_handshake_mac(cell);
- memcpy(handshake_ptr, mac, sizeof(mac));
- }
- /* Calculate the cell signature */
- {
- /* To calculate the sig we follow the same procedure as above. We first
- dump the cell up to the sig, and then calculate the sig */
- uint8_t cell_bytes_tmp[RELAY_PAYLOAD_SIZE] = {0};
- ed25519_signature_t sig;
- encoded_len = trn_cell_establish_intro_encode(cell_bytes_tmp,
- sizeof(cell_bytes_tmp),
- cell);
- if (encoded_len < 0) {
- log_warn(LD_OR, "Unable to pre-encode ESTABLISH_INTRO cell (2).");
- goto err;
- }
- tor_assert(encoded_len > ED25519_SIG_LEN);
- if (ed25519_sign_prefixed(&sig,
- cell_bytes_tmp,
- encoded_len -
- (ED25519_SIG_LEN + sizeof(cell->sig_len)),
- ESTABLISH_INTRO_SIG_PREFIX,
- &key_struct)) {
- log_warn(LD_BUG, "Unable to gen signature for ESTABLISH_INTRO cell.");
- goto err;
- }
- /* And write the signature to the cell */
- uint8_t *sig_ptr = trn_cell_establish_intro_getarray_sig(cell);
- memcpy(sig_ptr, sig.sig, sig_len);
- }
- /* We are done! Return the cell! */
- return cell;
- err:
- trn_cell_establish_intro_free(cell);
- return NULL;
- }
- #ifdef TOR_UNIT_TESTS
- /* Return the global service map size. Only used by unit test. */
- STATIC unsigned int
- get_hs_service_map_size(void)
- {
- return HT_SIZE(hs_service_map);
- }
- /* Return the staging list size. Only used by unit test. */
- STATIC int
- get_hs_service_staging_list_size(void)
- {
- return smartlist_len(hs_service_staging_list);
- }
- STATIC hs_service_ht *
- get_hs_service_map(void)
- {
- return hs_service_map;
- }
- STATIC hs_service_t *
- get_first_service(void)
- {
- hs_service_t **obj = HT_START(hs_service_ht, hs_service_map);
- if (obj == NULL) {
- return NULL;
- }
- return *obj;
- }
- #endif /* TOR_UNIT_TESTS */
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