diff options
Diffstat (limited to 'src/feature/hs/hs_circuit.c')
| -rw-r--r-- | src/feature/hs/hs_circuit.c | 409 |
1 files changed, 264 insertions, 145 deletions
diff --git a/src/feature/hs/hs_circuit.c b/src/feature/hs/hs_circuit.c index 8acfcbd65b..447f664f81 100644 --- a/src/feature/hs/hs_circuit.c +++ b/src/feature/hs/hs_circuit.c @@ -1,4 +1,4 @@ -/* Copyright (c) 2017-2019, The Tor Project, Inc. */ +/* Copyright (c) 2017-2020, The Tor Project, Inc. */ /* See LICENSE for licensing information */ /** @@ -15,15 +15,19 @@ #include "core/or/circuituse.h" #include "core/or/policies.h" #include "core/or/relay.h" +#include "core/or/crypt_path.h" #include "feature/client/circpathbias.h" #include "feature/hs/hs_cell.h" #include "feature/hs/hs_circuit.h" +#include "feature/hs/hs_ob.h" #include "feature/hs/hs_circuitmap.h" +#include "feature/hs/hs_client.h" #include "feature/hs/hs_ident.h" #include "feature/hs/hs_service.h" #include "feature/nodelist/describe.h" #include "feature/nodelist/nodelist.h" #include "feature/rend/rendservice.h" +#include "feature/rend/rendclient.h" #include "feature/stats/rephist.h" #include "lib/crypt_ops/crypto_dh.h" #include "lib/crypt_ops/crypto_rand.h" @@ -39,7 +43,7 @@ #include "feature/nodelist/node_st.h" #include "core/or/origin_circuit_st.h" -/* A circuit is about to become an e2e rendezvous circuit. Check +/** A circuit is about to become an e2e rendezvous circuit. Check * <b>circ_purpose</b> and ensure that it's properly set. Return true iff * circuit purpose is properly set, otherwise return false. */ static int @@ -66,7 +70,7 @@ circuit_purpose_is_correct_for_rend(unsigned int circ_purpose, return 1; } -/* Create and return a crypt path for the final hop of a v3 prop224 rendezvous +/** Create and return a crypt path for the final hop of a v3 prop224 rendezvous * circuit. Initialize the crypt path crypto using the output material from the * ntor key exchange at <b>ntor_key_seed</b>. * @@ -89,7 +93,7 @@ create_rend_cpath(const uint8_t *ntor_key_seed, size_t seed_len, cpath = tor_malloc_zero(sizeof(crypt_path_t)); cpath->magic = CRYPT_PATH_MAGIC; - if (circuit_init_cpath_crypto(cpath, (char*)keys, sizeof(keys), + if (cpath_init_circuit_crypto(cpath, (char*)keys, sizeof(keys), is_service_side, 1) < 0) { tor_free(cpath); goto err; @@ -100,7 +104,7 @@ create_rend_cpath(const uint8_t *ntor_key_seed, size_t seed_len, return cpath; } -/* We are a v2 legacy HS client: Create and return a crypt path for the hidden +/** We are a v2 legacy HS client: Create and return a crypt path for the hidden * service on the other side of the rendezvous circuit <b>circ</b>. Initialize * the crypt path crypto using the body of the RENDEZVOUS1 cell at * <b>rend_cell_body</b> (which must be at least DH1024_KEY_LEN+DIGEST_LEN @@ -126,7 +130,7 @@ create_rend_cpath_legacy(origin_circuit_t *circ, const uint8_t *rend_cell_body) goto err; } /* ... and set up cpath. */ - if (circuit_init_cpath_crypto(hop, + if (cpath_init_circuit_crypto(hop, keys+DIGEST_LEN, sizeof(keys)-DIGEST_LEN, 0, 0) < 0) goto err; @@ -151,7 +155,7 @@ create_rend_cpath_legacy(origin_circuit_t *circ, const uint8_t *rend_cell_body) return hop; } -/* Append the final <b>hop</b> to the cpath of the rend <b>circ</b>, and mark +/** Append the final <b>hop</b> to the cpath of the rend <b>circ</b>, and mark * <b>circ</b> ready for use to transfer HS relay cells. */ static void finalize_rend_circuit(origin_circuit_t *circ, crypt_path_t *hop, @@ -177,7 +181,7 @@ finalize_rend_circuit(origin_circuit_t *circ, crypt_path_t *hop, circ->hs_circ_has_timed_out = 0; /* Append the hop to the cpath of this circuit */ - onion_append_to_cpath(&circ->cpath, hop); + cpath_extend_linked_list(&circ->cpath, hop); /* In legacy code, 'pending_final_cpath' points to the final hop we just * appended to the cpath. We set the original pointer to NULL so that we @@ -192,7 +196,7 @@ finalize_rend_circuit(origin_circuit_t *circ, crypt_path_t *hop, } } -/* For a given circuit and a service introduction point object, register the +/** For a given circuit and a service introduction point object, register the * intro circuit to the circuitmap. This supports legacy intro point. */ static void register_intro_circ(const hs_service_intro_point_t *ip, @@ -210,7 +214,7 @@ register_intro_circ(const hs_service_intro_point_t *ip, } } -/* Return the number of opened introduction circuit for the given circuit that +/** Return the number of opened introduction circuit for the given circuit that * is matching its identity key. */ static unsigned int count_opened_desc_intro_point_circuits(const hs_service_t *service, @@ -242,7 +246,7 @@ count_opened_desc_intro_point_circuits(const hs_service_t *service, return count; } -/* From a given service, rendezvous cookie and handshake info, create a +/** From a given service, rendezvous cookie and handshake info, create a * rendezvous point circuit identifier. This can't fail. */ STATIC hs_ident_circuit_t * create_rp_circuit_identifier(const hs_service_t *service, @@ -258,8 +262,7 @@ create_rp_circuit_identifier(const hs_service_t *service, tor_assert(server_pk); tor_assert(keys); - ident = hs_ident_circuit_new(&service->keys.identity_pk, - HS_IDENT_CIRCUIT_RENDEZVOUS); + ident = hs_ident_circuit_new(&service->keys.identity_pk); /* Copy the RENDEZVOUS_COOKIE which is the unique identifier. */ memcpy(ident->rendezvous_cookie, rendezvous_cookie, sizeof(ident->rendezvous_cookie)); @@ -282,7 +285,7 @@ create_rp_circuit_identifier(const hs_service_t *service, return ident; } -/* From a given service and service intro point, create an introduction point +/** From a given service and service intro point, create an introduction point * circuit identifier. This can't fail. */ static hs_ident_circuit_t * create_intro_circuit_identifier(const hs_service_t *service, @@ -293,14 +296,13 @@ create_intro_circuit_identifier(const hs_service_t *service, tor_assert(service); tor_assert(ip); - ident = hs_ident_circuit_new(&service->keys.identity_pk, - HS_IDENT_CIRCUIT_INTRO); + ident = hs_ident_circuit_new(&service->keys.identity_pk); ed25519_pubkey_copy(&ident->intro_auth_pk, &ip->auth_key_kp.pubkey); return ident; } -/* For a given introduction point and an introduction circuit, send the +/** For a given introduction point and an introduction circuit, send the * ESTABLISH_INTRO cell. The service object is used for logging. This can fail * and if so, the circuit is closed and the intro point object is flagged * that the circuit is not established anymore which is important for the @@ -318,7 +320,7 @@ send_establish_intro(const hs_service_t *service, /* Encode establish intro cell. */ cell_len = hs_cell_build_establish_intro(circ->cpath->prev->rend_circ_nonce, - ip, payload); + &service->config, ip, payload); if (cell_len < 0) { log_warn(LD_REND, "Unable to encode ESTABLISH_INTRO cell for service %s " "on circuit %u. Closing circuit.", @@ -350,7 +352,7 @@ send_establish_intro(const hs_service_t *service, memwipe(payload, 0, sizeof(payload)); } -/* Return a string constant describing the anonymity of service. */ +/** Return a string constant describing the anonymity of service. */ static const char * get_service_anonymity_string(const hs_service_t *service) { @@ -361,15 +363,15 @@ get_service_anonymity_string(const hs_service_t *service) } } -/* For a given service, the ntor onion key and a rendezvous cookie, launch a +/** For a given service, the ntor onion key and a rendezvous cookie, launch a * circuit to the rendezvous point specified by the link specifiers. On * success, a circuit identifier is attached to the circuit with the needed * data. This function will try to open a circuit for a maximum value of * MAX_REND_FAILURES then it will give up. */ -static void -launch_rendezvous_point_circuit(const hs_service_t *service, - const hs_service_intro_point_t *ip, - const hs_cell_introduce2_data_t *data) +MOCK_IMPL(STATIC void, +launch_rendezvous_point_circuit,(const hs_service_t *service, + const hs_service_intro_point_t *ip, + const hs_cell_introduce2_data_t *data)) { int circ_needs_uptime; time_t now = time(NULL); @@ -388,10 +390,7 @@ launch_rendezvous_point_circuit(const hs_service_t *service, &data->onion_pk, service->config.is_single_onion); if (info == NULL) { - /* We are done here, we can't extend to the rendezvous point. - * If you're running an IPv6-only v3 single onion service on 0.3.2 or with - * 0.3.2 clients, and somehow disable the option check, it will fail here. - */ + /* We are done here, we can't extend to the rendezvous point. */ log_fn(LOG_PROTOCOL_WARN, LD_REND, "Not enough info to open a circuit to a rendezvous point for " "%s service %s.", @@ -473,7 +472,7 @@ launch_rendezvous_point_circuit(const hs_service_t *service, extend_info_free(info); } -/* Return true iff the given service rendezvous circuit circ is allowed for a +/** Return true iff the given service rendezvous circuit circ is allowed for a * relaunch to the rendezvous point. */ static int can_relaunch_service_rendezvous_point(const origin_circuit_t *circ) @@ -520,7 +519,7 @@ can_relaunch_service_rendezvous_point(const origin_circuit_t *circ) return 0; } -/* Retry the rendezvous point of circ by launching a new circuit to it. */ +/** Retry the rendezvous point of circ by launching a new circuit to it. */ static void retry_service_rendezvous_point(const origin_circuit_t *circ) { @@ -569,82 +568,7 @@ retry_service_rendezvous_point(const origin_circuit_t *circ) return; } -/* Add all possible link specifiers in node to lspecs: - * - legacy ID is mandatory thus MUST be present in node; - * - include ed25519 link specifier if present in the node, and the node - * supports ed25519 link authentication, even if its link versions are not - * compatible with us; - * - include IPv4 link specifier, if the primary address is not IPv4, log a - * BUG() warning, and return an empty smartlist; - * - include IPv6 link specifier if present in the node. */ -static void -get_lspecs_from_node(const node_t *node, smartlist_t *lspecs) -{ - link_specifier_t *ls; - tor_addr_port_t ap; - - tor_assert(node); - tor_assert(lspecs); - - /* Get the relay's IPv4 address. */ - node_get_prim_orport(node, &ap); - - /* We expect the node's primary address to be a valid IPv4 address. - * This conforms to the protocol, which requires either an IPv4 or IPv6 - * address (or both). */ - if (BUG(!tor_addr_is_v4(&ap.addr)) || - BUG(!tor_addr_port_is_valid_ap(&ap, 0))) { - return; - } - - ls = link_specifier_new(); - link_specifier_set_ls_type(ls, LS_IPV4); - link_specifier_set_un_ipv4_addr(ls, tor_addr_to_ipv4h(&ap.addr)); - link_specifier_set_un_ipv4_port(ls, ap.port); - /* Four bytes IPv4 and two bytes port. */ - link_specifier_set_ls_len(ls, sizeof(ap.addr.addr.in_addr) + - sizeof(ap.port)); - smartlist_add(lspecs, ls); - - /* Legacy ID is mandatory and will always be present in node. */ - ls = link_specifier_new(); - link_specifier_set_ls_type(ls, LS_LEGACY_ID); - memcpy(link_specifier_getarray_un_legacy_id(ls), node->identity, - link_specifier_getlen_un_legacy_id(ls)); - link_specifier_set_ls_len(ls, link_specifier_getlen_un_legacy_id(ls)); - smartlist_add(lspecs, ls); - - /* ed25519 ID is only included if the node has it, and the node declares a - protocol version that supports ed25519 link authentication, even if that - link version is not compatible with us. (We are sending the ed25519 key - to another tor, which may support different link versions.) */ - if (!ed25519_public_key_is_zero(&node->ed25519_id) && - node_supports_ed25519_link_authentication(node, 0)) { - ls = link_specifier_new(); - link_specifier_set_ls_type(ls, LS_ED25519_ID); - memcpy(link_specifier_getarray_un_ed25519_id(ls), &node->ed25519_id, - link_specifier_getlen_un_ed25519_id(ls)); - link_specifier_set_ls_len(ls, link_specifier_getlen_un_ed25519_id(ls)); - smartlist_add(lspecs, ls); - } - - /* Check for IPv6. If so, include it as well. */ - if (node_has_ipv6_orport(node)) { - ls = link_specifier_new(); - node_get_pref_ipv6_orport(node, &ap); - link_specifier_set_ls_type(ls, LS_IPV6); - size_t addr_len = link_specifier_getlen_un_ipv6_addr(ls); - const uint8_t *in6_addr = tor_addr_to_in6_addr8(&ap.addr); - uint8_t *ipv6_array = link_specifier_getarray_un_ipv6_addr(ls); - memcpy(ipv6_array, in6_addr, addr_len); - link_specifier_set_un_ipv6_port(ls, ap.port); - /* Sixteen bytes IPv6 and two bytes port. */ - link_specifier_set_ls_len(ls, addr_len + sizeof(ap.port)); - smartlist_add(lspecs, ls); - } -} - -/* Using the given descriptor intro point ip, the node of the +/** Using the given descriptor intro point ip, the node of the * rendezvous point rp_node and the service's subcredential, populate the * already allocated intro1_data object with the needed key material and link * specifiers. @@ -655,7 +579,7 @@ get_lspecs_from_node(const node_t *node, smartlist_t *lspecs) static int setup_introduce1_data(const hs_desc_intro_point_t *ip, const node_t *rp_node, - const uint8_t *subcredential, + const hs_subcredential_t *subcredential, hs_cell_introduce1_data_t *intro1_data) { int ret = -1; @@ -666,10 +590,9 @@ setup_introduce1_data(const hs_desc_intro_point_t *ip, tor_assert(subcredential); tor_assert(intro1_data); - /* Build the link specifiers from the extend information of the rendezvous - * circuit that we've picked previously. */ - rp_lspecs = smartlist_new(); - get_lspecs_from_node(rp_node, rp_lspecs); + /* Build the link specifiers from the node at the end of the rendezvous + * circuit that we opened for this introduction. */ + rp_lspecs = node_get_link_specifier_smartlist(rp_node, 0); if (smartlist_len(rp_lspecs) == 0) { /* We can't rendezvous without link specifiers. */ smartlist_free(rp_lspecs); @@ -698,11 +621,41 @@ setup_introduce1_data(const hs_desc_intro_point_t *ip, return ret; } +/** Helper: cleanup function for client circuit. This is for every HS version. + * It is called from hs_circ_cleanup_on_close() entry point. */ +static void +cleanup_on_close_client_circ(circuit_t *circ) +{ + tor_assert(circ); + + if (circuit_is_hs_v3(circ)) { + hs_client_circuit_cleanup_on_close(circ); + } + /* It is possible the circuit has an HS purpose but no identifier (rend_data + * or hs_ident). Thus possible that this passes through. */ +} + +/** Helper: cleanup function for client circuit. This is for every HS version. + * It is called from hs_circ_cleanup_on_free() entry point. */ +static void +cleanup_on_free_client_circ(circuit_t *circ) +{ + tor_assert(circ); + + if (circuit_is_hs_v2(circ)) { + rend_client_circuit_cleanup_on_free(circ); + } else if (circuit_is_hs_v3(circ)) { + hs_client_circuit_cleanup_on_free(circ); + } + /* It is possible the circuit has an HS purpose but no identifier (rend_data + * or hs_ident). Thus possible that this passes through. */ +} + /* ========== */ /* Public API */ /* ========== */ -/* Return an introduction point circuit matching the given intro point object. +/** Return an introduction point circuit matching the given intro point object. * NULL is returned is no such circuit can be found. */ origin_circuit_t * hs_circ_service_get_intro_circ(const hs_service_intro_point_t *ip) @@ -717,7 +670,29 @@ hs_circ_service_get_intro_circ(const hs_service_intro_point_t *ip) } } -/* Called when we fail building a rendezvous circuit at some point other than +/** Return an introduction point established circuit matching the given intro + * point object. The circuit purpose has to be CIRCUIT_PURPOSE_S_INTRO. NULL + * is returned is no such circuit can be found. */ +origin_circuit_t * +hs_circ_service_get_established_intro_circ(const hs_service_intro_point_t *ip) +{ + origin_circuit_t *circ; + + tor_assert(ip); + + if (ip->base.is_only_legacy) { + circ = hs_circuitmap_get_intro_circ_v2_service_side(ip->legacy_key_digest); + } else { + circ = hs_circuitmap_get_intro_circ_v3_service_side( + &ip->auth_key_kp.pubkey); + } + + /* Only return circuit if it is established. */ + return (circ && TO_CIRCUIT(circ)->purpose == CIRCUIT_PURPOSE_S_INTRO) ? + circ : NULL; +} + +/** Called when we fail building a rendezvous circuit at some point other than * the last hop: launches a new circuit to the same rendezvous point. This * supports legacy service. * @@ -757,7 +732,7 @@ hs_circ_retry_service_rendezvous_point(origin_circuit_t *circ) return; } -/* For a given service and a service intro point, launch a circuit to the +/** For a given service and a service intro point, launch a circuit to the * extend info ei. If the service is a single onion, and direct_conn is true, * a one-hop circuit will be requested. * @@ -818,7 +793,7 @@ hs_circ_launch_intro_point(hs_service_t *service, return ret; } -/* Called when a service introduction point circuit is done building. Given +/** Called when a service introduction point circuit is done building. Given * the service and intro point object, this function will send the * ESTABLISH_INTRO cell on the circuit. Return 0 on success. Return 1 if the * circuit has been repurposed to General because we already have too many @@ -887,7 +862,7 @@ hs_circ_service_intro_has_opened(hs_service_t *service, return ret; } -/* Called when a service rendezvous point circuit is done building. Given the +/** Called when a service rendezvous point circuit is done building. Given the * service and the circuit, this function will send a RENDEZVOUS1 cell on the * circuit using the information in the circuit identifier. If the cell can't * be sent, the circuit is closed. */ @@ -953,7 +928,7 @@ hs_circ_service_rp_has_opened(const hs_service_t *service, memwipe(payload, 0, sizeof(payload)); } -/* Circ has been expecting an INTRO_ESTABLISHED cell that just arrived. Handle +/** Circ has been expecting an INTRO_ESTABLISHED cell that just arrived. Handle * the INTRO_ESTABLISHED cell payload of length payload_len arriving on the * given introduction circuit circ. The service is only used for logging * purposes. Return 0 on success else a negative value. */ @@ -998,7 +973,43 @@ hs_circ_handle_intro_established(const hs_service_t *service, return ret; } -/* We just received an INTRODUCE2 cell on the established introduction circuit +/** + * Go into <b>data</b> and add the right subcredential to be able to handle + * this incoming cell. + * + * <b>desc_subcred</b> is the subcredential of the descriptor that corresponds + * to the intro point that received this intro request. This subcredential + * should be used if we are not an onionbalance instance. + * + * Return 0 if everything went well, or -1 in case of internal error. + */ +static int +get_subcredential_for_handling_intro2_cell(const hs_service_t *service, + hs_cell_introduce2_data_t *data, + const hs_subcredential_t *desc_subcred) +{ + /* Handle the simple case first: We are not an onionbalance instance and we + * should just use the regular descriptor subcredential */ + if (!hs_ob_service_is_instance(service)) { + data->n_subcredentials = 1; + data->subcredentials = desc_subcred; + return 0; + } + + /* This should not happen since we should have made onionbalance + * subcredentials when we created our descriptors. */ + if (BUG(!service->state.ob_subcreds)) { + return -1; + } + + /* We are an onionbalance instance: */ + data->n_subcredentials = service->state.n_ob_subcreds; + data->subcredentials = service->state.ob_subcreds; + + return 0; +} + +/** We just received an INTRODUCE2 cell on the established introduction circuit * circ. Handle the INTRODUCE2 payload of size payload_len for the given * circuit and service. This cell is associated with the intro point object ip * and the subcredential. Return 0 on success else a negative value. */ @@ -1006,7 +1017,7 @@ int hs_circ_handle_introduce2(const hs_service_t *service, const origin_circuit_t *circ, hs_service_intro_point_t *ip, - const uint8_t *subcredential, + const hs_subcredential_t *subcredential, const uint8_t *payload, size_t payload_len) { int ret = -1; @@ -1023,12 +1034,16 @@ hs_circ_handle_introduce2(const hs_service_t *service, * parsed, decrypted and key material computed correctly. */ data.auth_pk = &ip->auth_key_kp.pubkey; data.enc_kp = &ip->enc_key_kp; - data.subcredential = subcredential; data.payload = payload; data.payload_len = payload_len; data.link_specifiers = smartlist_new(); data.replay_cache = ip->replay_cache; + if (get_subcredential_for_handling_intro2_cell(service, + &data, subcredential)) { + goto done; + } + if (hs_cell_parse_introduce2(&data, circ, service) < 0) { goto done; } @@ -1060,14 +1075,12 @@ hs_circ_handle_introduce2(const hs_service_t *service, ret = 0; done: - SMARTLIST_FOREACH(data.link_specifiers, link_specifier_t *, lspec, - link_specifier_free(lspec)); - smartlist_free(data.link_specifiers); + link_specifier_smartlist_free(data.link_specifiers); memwipe(&data, 0, sizeof(data)); return ret; } -/* Circuit <b>circ</b> just finished the rend ntor key exchange. Use the key +/** Circuit <b>circ</b> just finished the rend ntor key exchange. Use the key * exchange output material at <b>ntor_key_seed</b> and setup <b>circ</b> to * serve as a rendezvous end-to-end circuit between the client and the * service. If <b>is_service_side</b> is set, then we are the hidden service @@ -1097,7 +1110,7 @@ hs_circuit_setup_e2e_rend_circ(origin_circuit_t *circ, return 0; } -/* We are a v2 legacy HS client and we just received a RENDEZVOUS1 cell +/** We are a v2 legacy HS client and we just received a RENDEZVOUS1 cell * <b>rend_cell_body</b> on <b>circ</b>. Finish up the DH key exchange and then * extend the crypt path of <b>circ</b> so that the hidden service is on the * other side. */ @@ -1122,7 +1135,7 @@ hs_circuit_setup_e2e_rend_circ_legacy_client(origin_circuit_t *circ, return 0; } -/* Given the introduction circuit intro_circ, the rendezvous circuit +/** Given the introduction circuit intro_circ, the rendezvous circuit * rend_circ, a descriptor intro point object ip and the service's * subcredential, send an INTRODUCE1 cell on intro_circ. * @@ -1134,7 +1147,7 @@ int hs_circ_send_introduce1(origin_circuit_t *intro_circ, origin_circuit_t *rend_circ, const hs_desc_intro_point_t *ip, - const uint8_t *subcredential) + const hs_subcredential_t *subcredential) { int ret = -1; ssize_t payload_len; @@ -1207,7 +1220,7 @@ hs_circ_send_introduce1(origin_circuit_t *intro_circ, return ret; } -/* Send an ESTABLISH_RENDEZVOUS cell along the rendezvous circuit circ. On +/** Send an ESTABLISH_RENDEZVOUS cell along the rendezvous circuit circ. On * success, 0 is returned else -1 and the circuit is marked for close. */ int hs_circ_send_establish_rendezvous(origin_circuit_t *circ) @@ -1258,30 +1271,136 @@ hs_circ_send_establish_rendezvous(origin_circuit_t *circ) return -1; } -/* We are about to close or free this <b>circ</b>. Clean it up from any - * related HS data structures. This function can be called multiple times - * safely for the same circuit. */ +/** Circuit cleanup strategy: + * + * What follows is a series of functions that notifies the HS subsystem of 3 + * different circuit cleanup phase: close, free and repurpose. + * + * Tor can call any of those in any orders so they have to be safe between + * each other. In other words, the free should never depend on close to be + * called before. + * + * The "on_close()" is called from circuit_mark_for_close() which is + * considered the tor fast path and thus as little work as possible should + * done in that function. Currently, we only remove the circuit from the HS + * circuit map and move on. + * + * The "on_free()" is called from circuit circuit_free_() and it is very + * important that at the end of the function, no state or objects related to + * this circuit remains alive. + * + * The "on_repurpose()" is called from circuit_change_purpose() for which we + * simply remove it from the HS circuit map. We do not have other cleanup + * requirements after that. + * + * NOTE: The onion service code, specifically the service code, cleans up + * lingering objects or state if any of its circuit disappear which is why + * our cleanup strategy doesn't involve any service specific actions. As long + * as the circuit is removed from the HS circuit map, it won't be used. + */ + +/** We are about to close this <b>circ</b>. Clean it up from any related HS + * data structures. This function can be called multiple times safely for the + * same circuit. */ void -hs_circ_cleanup(circuit_t *circ) +hs_circ_cleanup_on_close(circuit_t *circ) { tor_assert(circ); - /* If it's a service-side intro circ, notify the HS subsystem for the intro - * point circuit closing so it can be dealt with cleanly. */ - if (circ->purpose == CIRCUIT_PURPOSE_S_ESTABLISH_INTRO || - circ->purpose == CIRCUIT_PURPOSE_S_INTRO) { - hs_service_intro_circ_has_closed(TO_ORIGIN_CIRCUIT(circ)); + if (circuit_purpose_is_hs_client(circ->purpose)) { + cleanup_on_close_client_circ(circ); } - /* Clear HS circuitmap token for this circ (if any). Very important to be - * done after the HS subsystem has been notified of the close else the - * circuit will not be found. - * - * We do this at the close if possible because from that point on, the - * circuit is good as dead. We can't rely on removing it in the circuit - * free() function because we open a race window between the close and free - * where we can't register a new circuit for the same intro point. */ + /* On close, we simply remove it from the circuit map. It can not be used + * anymore. We keep this code path fast and lean. */ + + if (circ->hs_token) { + hs_circuitmap_remove_circuit(circ); + } +} + +/** We are about to free this <b>circ</b>. Clean it up from any related HS + * data structures. This function can be called multiple times safely for the + * same circuit. */ +void +hs_circ_cleanup_on_free(circuit_t *circ) +{ + tor_assert(circ); + + /* NOTE: Bulk of the work of cleaning up a circuit is done here. */ + + if (circuit_purpose_is_hs_client(circ->purpose)) { + cleanup_on_free_client_circ(circ); + } + + /* We have no assurance that the given HS circuit has been closed before and + * thus removed from the HS map. This actually happens in unit tests. */ if (circ->hs_token) { hs_circuitmap_remove_circuit(circ); } } + +/** We are about to repurpose this <b>circ</b>. Clean it up from any related + * HS data structures. This function can be called multiple times safely for + * the same circuit. */ +void +hs_circ_cleanup_on_repurpose(circuit_t *circ) +{ + tor_assert(circ); + + /* On repurpose, we simply remove it from the circuit map but we do not do + * the on_free actions since we don't treat a repurpose as something we need + * to report in the client cache failure. */ + + if (circ->hs_token) { + hs_circuitmap_remove_circuit(circ); + } +} + +/** Return true iff the given established client rendezvous circuit was sent + * into the INTRODUCE1 cell. This is called so we can take a decision on + * expiring or not the circuit. + * + * The caller MUST make sure the circuit is an established client rendezvous + * circuit (purpose: CIRCUIT_PURPOSE_C_REND_READY). + * + * This function supports all onion service versions. */ +bool +hs_circ_is_rend_sent_in_intro1(const origin_circuit_t *circ) +{ + tor_assert(circ); + /* This can only be called for a rendezvous circuit that is an established + * confirmed rendezsvous circuit but without an introduction ACK. */ + tor_assert(TO_CIRCUIT(circ)->purpose == CIRCUIT_PURPOSE_C_REND_READY); + + /* The v2 and v3 circuit are handled differently: + * + * v2: A circ's pending_final_cpath field is non-NULL iff it is a rend circ + * and we have tried to send an INTRODUCE1 cell specifying it. Thus, if the + * pending_final_cpath field *is* NULL, then we want to not spare it. + * + * v3: When the INTRODUCE1 cell is sent, the introduction encryption public + * key is copied in the rendezvous circuit hs identifier. If it is a valid + * key, we know that this circuit is waiting the ACK on the introduction + * circuit. We want to _not_ spare the circuit if the key was never set. */ + + if (circ->rend_data) { + /* v2. */ + if (circ->build_state && circ->build_state->pending_final_cpath != NULL) { + return true; + } + } else if (circ->hs_ident) { + /* v3. */ + if (curve25519_public_key_is_ok(&circ->hs_ident->intro_enc_pk)) { + return true; + } + } else { + /* A circuit with an HS purpose without an hs_ident or rend_data in theory + * can not happen. In case, scream loudly and return false to the caller + * that the rendezvous was not sent in the INTRO1 cell. */ + tor_assert_nonfatal_unreached(); + } + + /* The rendezvous has not been specified in the INTRODUCE1 cell. */ + return false; +} |