August 2019 - tor-commits - lists.torproject.org

[tor/master] Merge branch 'bug23818_029' into bug23818_035
by dgoulet＠torproject.org 29 Aug '19

29 Aug '19

commit 14b5f40b54e41a2eb6cf73b2a4f42193b9f2d6d2 Merge: 5653b93a1 231a74363 Author: teor <teor(a)torproject.org> Date: Fri Aug 23 15:09:19 2019 +1000 Merge branch 'bug23818_029' into bug23818_035 changes/bug23818_v2 | 6 ++++++ src/feature/rend/rendservice.c | 19 +++++++++++++++---- 2 files changed, 21 insertions(+), 4 deletions(-) diff --cc src/feature/rend/rendservice.c index 5ee084b0b,000000000..c96ecec30 mode 100644,000000..100644 --- a/src/feature/rend/rendservice.c +++ b/src/feature/rend/rendservice.c @@@ -1,4487 -1,0 +1,4498 @@@ +/* Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. + * Copyright (c) 2007-2019, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +/** + * \file rendservice.c + * \brief The hidden-service side of rendezvous functionality. + **/ + +#define RENDSERVICE_PRIVATE + +#include "core/or/or.h" + +#include "app/config/config.h" +#include "core/mainloop/mainloop.h" +#include "core/or/circuitbuild.h" +#include "core/or/circuitlist.h" +#include "core/or/circuituse.h" +#include "core/or/policies.h" +#include "core/or/relay.h" +#include "feature/client/circpathbias.h" +#include "feature/control/control.h" +#include "feature/dirclient/dirclient.h" +#include "feature/dircommon/directory.h" +#include "feature/hs/hs_common.h" +#include "feature/hs/hs_config.h" +#include "feature/hs_common/replaycache.h" +#include "feature/keymgt/loadkey.h" +#include "feature/nodelist/describe.h" +#include "feature/nodelist/networkstatus.h" +#include "feature/nodelist/nickname.h" +#include "feature/nodelist/node_select.h" +#include "feature/nodelist/nodelist.h" +#include "feature/nodelist/routerset.h" +#include "feature/rend/rendclient.h" +#include "feature/rend/rendcommon.h" +#include "feature/rend/rendparse.h" +#include "feature/rend/rendservice.h" +#include "feature/stats/predict_ports.h" +#include "lib/crypt_ops/crypto_dh.h" +#include "lib/crypt_ops/crypto_rand.h" +#include "lib/crypt_ops/crypto_util.h" +#include "lib/encoding/confline.h" +#include "lib/net/resolve.h" + +#include "core/or/cpath_build_state_st.h" +#include "core/or/crypt_path_st.h" +#include "core/or/crypt_path_reference_st.h" +#include "core/or/edge_connection_st.h" +#include "core/or/extend_info_st.h" +#include "feature/nodelist/networkstatus_st.h" +#include "core/or/origin_circuit_st.h" +#include "feature/rend/rend_authorized_client_st.h" +#include "feature/rend/rend_encoded_v2_service_descriptor_st.h" +#include "feature/rend/rend_intro_point_st.h" +#include "feature/rend/rend_service_descriptor_st.h" +#include "feature/nodelist/routerstatus_st.h" + +#ifdef HAVE_FCNTL_H +#include <fcntl.h> +#endif +#ifdef HAVE_UNISTD_H +#include <unistd.h> +#endif +#ifdef HAVE_SYS_STAT_H +#include <sys/stat.h> +#endif + +struct rend_service_t; +static origin_circuit_t *find_intro_circuit(rend_intro_point_t *intro, + const char *pk_digest); +static rend_intro_point_t *find_intro_point(origin_circuit_t *circ); +static rend_intro_point_t *find_expiring_intro_point( + struct rend_service_t *service, origin_circuit_t *circ); + +static extend_info_t *find_rp_for_intro( + const rend_intro_cell_t *intro, + char **err_msg_out); + +static int intro_point_accepted_intro_count(rend_intro_point_t *intro); +static int intro_point_should_expire_now(rend_intro_point_t *intro, + time_t now); +static int rend_service_derive_key_digests(struct rend_service_t *s); +static int rend_service_load_keys(struct rend_service_t *s); +static int rend_service_load_auth_keys(struct rend_service_t *s, + const char *hfname); +static struct rend_service_t *rend_service_get_by_pk_digest( + const char* digest); +static struct rend_service_t *rend_service_get_by_service_id(const char *id); +static const char *rend_service_escaped_dir( + const struct rend_service_t *s); + +static ssize_t rend_service_parse_intro_for_v0_or_v1( + rend_intro_cell_t *intro, + const uint8_t *buf, + size_t plaintext_len, + char **err_msg_out); +static ssize_t rend_service_parse_intro_for_v2( + rend_intro_cell_t *intro, + const uint8_t *buf, + size_t plaintext_len, + char **err_msg_out); +static ssize_t rend_service_parse_intro_for_v3( + rend_intro_cell_t *intro, + const uint8_t *buf, + size_t plaintext_len, + char **err_msg_out); + +static int rend_service_check_private_dir(const or_options_t *options, + const rend_service_t *s, + int create); +static const smartlist_t* rend_get_service_list( + const smartlist_t* substitute_service_list); +static smartlist_t* rend_get_service_list_mutable( + smartlist_t* substitute_service_list); +static int rend_max_intro_circs_per_period(unsigned int n_intro_points_wanted); + +/* Hidden service directory file names: + * new file names should be added to rend_service_add_filenames_to_list() + * for sandboxing purposes. */ +static const char *private_key_fname = "private_key"; +static const char *hostname_fname = "hostname"; +static const char *client_keys_fname = "client_keys"; +static const char *sos_poison_fname = "onion_service_non_anonymous"; + +/** A list of rend_service_t's for services run on this OP. */ +static smartlist_t *rend_service_list = NULL; +/** A list of rend_service_t's for services run on this OP which is used as a + * staging area before they are put in the main list in order to prune dying + * service on config reload. */ +static smartlist_t *rend_service_staging_list = NULL; + +/* Like rend_get_service_list_mutable, but returns a read-only list. */ +static const smartlist_t* +rend_get_service_list(const smartlist_t* substitute_service_list) +{ + /* It is safe to cast away the const here, because + * rend_get_service_list_mutable does not actually modify the list */ + return rend_get_service_list_mutable((smartlist_t*)substitute_service_list); +} + +/* Return a mutable list of hidden services. + * If substitute_service_list is not NULL, return it. + * Otherwise, check if the global rend_service_list is non-NULL, and if so, + * return it. + * Otherwise, log a BUG message and return NULL. + * */ +static smartlist_t* +rend_get_service_list_mutable(smartlist_t* substitute_service_list) +{ + if (substitute_service_list) { + return substitute_service_list; + } + + /* If no special service list is provided, then just use the global one. */ + + if (BUG(!rend_service_list)) { + /* No global HS list, which is a programmer error. */ + return NULL; + } + + return rend_service_list; +} + +/** Tells if onion service s is ephemeral. + */ +static unsigned int +rend_service_is_ephemeral(const struct rend_service_t *s) +{ + return (s->directory == NULL); +} + +/** Returns a escaped string representation of the service, s. + */ +static const char * +rend_service_escaped_dir(const struct rend_service_t *s) +{ + return rend_service_is_ephemeral(s) ? "[EPHEMERAL]" : escaped(s->directory); +} + +/** Return the number of rendezvous services we have configured. */ +int +rend_num_services(void) +{ + if (!rend_service_list) + return 0; + return smartlist_len(rend_service_list); +} + +/** Helper: free storage held by a single service authorized client entry. */ +void +rend_authorized_client_free_(rend_authorized_client_t *client) +{ + if (!client) + return; + if (client->client_key) + crypto_pk_free(client->client_key); + if (client->client_name) + memwipe(client->client_name, 0, strlen(client->client_name)); + tor_free(client->client_name); + memwipe(client->descriptor_cookie, 0, sizeof(client->descriptor_cookie)); + tor_free(client); +} + +/** Helper for strmap_free. */ +static void +rend_authorized_client_free_void(void *authorized_client) +{ + rend_authorized_client_free_(authorized_client); +} + +/** Release the storage held by service. + */ +STATIC void +rend_service_free_(rend_service_t *service) +{ + if (!service) + return; + + tor_free(service->directory); + if (service->ports) { + SMARTLIST_FOREACH(service->ports, rend_service_port_config_t*, p, + rend_service_port_config_free(p)); + smartlist_free(service->ports); + } + if (service->private_key) + crypto_pk_free(service->private_key); + if (service->intro_nodes) { + SMARTLIST_FOREACH(service->intro_nodes, rend_intro_point_t *, intro, + rend_intro_point_free(intro);); + smartlist_free(service->intro_nodes); + } + if (service->expiring_nodes) { + SMARTLIST_FOREACH(service->expiring_nodes, rend_intro_point_t *, intro, + rend_intro_point_free(intro);); + smartlist_free(service->expiring_nodes); + } + + rend_service_descriptor_free(service->desc); + if (service->clients) { + SMARTLIST_FOREACH(service->clients, rend_authorized_client_t *, c, + rend_authorized_client_free(c);); + smartlist_free(service->clients); + } + if (service->accepted_intro_dh_parts) { + replaycache_free(service->accepted_intro_dh_parts); + } + tor_free(service); +} + +/* Release all the storage held in rend_service_staging_list. */ +void +rend_service_free_staging_list(void) +{ + if (rend_service_staging_list) { + SMARTLIST_FOREACH(rend_service_staging_list, rend_service_t*, ptr, + rend_service_free(ptr)); + smartlist_free(rend_service_staging_list); + rend_service_staging_list = NULL; + } +} + +/** Release all the storage held in both rend_service_list and + * rend_service_staging_list. */ +void +rend_service_free_all(void) +{ + if (rend_service_list) { + SMARTLIST_FOREACH(rend_service_list, rend_service_t*, ptr, + rend_service_free(ptr)); + smartlist_free(rend_service_list); + rend_service_list = NULL; + } + rend_service_free_staging_list(); +} + +/* Initialize the subsystem. */ +void +rend_service_init(void) +{ + tor_assert(!rend_service_list); + tor_assert(!rend_service_staging_list); + + rend_service_list = smartlist_new(); + rend_service_staging_list = smartlist_new(); +} + +/* Validate a service. Use the service_list to make sure there + * is no duplicate entry for the given service object. Return 0 if valid else + * -1 if not.*/ +static int +rend_validate_service(const smartlist_t *service_list, + const rend_service_t *service) +{ + tor_assert(service_list); + tor_assert(service); + + if (service->max_streams_per_circuit < 0) { + log_warn(LD_CONFIG, "Hidden service (%s) configured with negative max " + "streams per circuit.", + rend_service_escaped_dir(service)); + goto invalid; + } + + if (service->max_streams_close_circuit < 0 || + service->max_streams_close_circuit > 1) { + log_warn(LD_CONFIG, "Hidden service (%s) configured with invalid " + "max streams handling.", + rend_service_escaped_dir(service)); + goto invalid; + } + + if (service->auth_type != REND_NO_AUTH && + (!service->clients || smartlist_len(service->clients) == 0)) { + log_warn(LD_CONFIG, "Hidden service (%s) with client authorization but " + "no clients.", + rend_service_escaped_dir(service)); + goto invalid; + } + + if (!service->ports || !smartlist_len(service->ports)) { + log_warn(LD_CONFIG, "Hidden service (%s) with no ports configured.", + rend_service_escaped_dir(service)); + goto invalid; + } + + /* Valid. */ + return 0; + invalid: + return -1; +} + +/** Add it to service_list, or to the global rend_service_list if + * service_list is NULL. Return 0 on success. On failure, free + * service and return -1. Takes ownership of service. */ +static int +rend_add_service(smartlist_t *service_list, rend_service_t *service) +{ + int i; + rend_service_port_config_t *p; + + tor_assert(service); + + smartlist_t *s_list = rend_get_service_list_mutable(service_list); + /* We must have a service list, even if it's a temporary one, so we can + * check for duplicate services */ + if (BUG(!s_list)) { + rend_service_free(service); + return -1; + } + + service->intro_nodes = smartlist_new(); + service->expiring_nodes = smartlist_new(); + + log_debug(LD_REND,"Configuring service with directory %s", + rend_service_escaped_dir(service)); + for (i = 0; i < smartlist_len(service->ports); ++i) { + p = smartlist_get(service->ports, i); + if (!(p->is_unix_addr)) { + log_debug(LD_REND, + "Service maps port %d to %s", + p->virtual_port, + fmt_addrport(&p->real_addr, p->real_port)); + } else { +#ifdef HAVE_SYS_UN_H + log_debug(LD_REND, + "Service maps port %d to socket at \"%s\"", + p->virtual_port, p->unix_addr); +#else + log_warn(LD_BUG, + "Service maps port %d to an AF_UNIX socket, but we " + "have no AF_UNIX support on this platform. This is " + "probably a bug.", + p->virtual_port); + rend_service_free(service); + return -1; +#endif /* defined(HAVE_SYS_UN_H) */ + } + } + /* The service passed all the checks */ + tor_assert(s_list); + smartlist_add(s_list, service); + + /* Notify that our global service list has changed only if this new service + * went into our global list. If not, when we move service from the staging + * list to the new list, a notify is triggered. */ + if (s_list == rend_service_list) { + hs_service_map_has_changed(); + } + return 0; +} + +/** Return a new rend_service_port_config_t with its path set to + * socket_path or empty if socket_path is NULL */ +static rend_service_port_config_t * +rend_service_port_config_new(const char *socket_path) +{ + if (!socket_path) + return tor_malloc_zero(sizeof(rend_service_port_config_t) + 1); + + const size_t pathlen = strlen(socket_path) + 1; + rend_service_port_config_t *conf = + tor_malloc_zero(sizeof(rend_service_port_config_t) + pathlen); + memcpy(conf->unix_addr, socket_path, pathlen); + conf->is_unix_addr = 1; + return conf; +} + +/** Parses a virtual-port to real-port/socket mapping separated by + * the provided separator and returns a new rend_service_port_config_t, + * or NULL and an optional error string on failure. + * + * The format is: VirtualPort SEP (IP|RealPort|IP:RealPort|'socket':path)? + * + * IP defaults to 127.0.0.1; RealPort defaults to VirtualPort. + */ +rend_service_port_config_t * +rend_service_parse_port_config(const char *string, const char *sep, + char **err_msg_out) +{ + smartlist_t *sl; + int virtport; + int realport = 0; + uint16_t p; + tor_addr_t addr; + rend_service_port_config_t *result = NULL; + unsigned int is_unix_addr = 0; + const char *socket_path = NULL; + char *err_msg = NULL; + char *addrport = NULL; + + sl = smartlist_new(); + smartlist_split_string(sl, string, sep, + SPLIT_SKIP_SPACE|SPLIT_IGNORE_BLANK, 2); + if (smartlist_len(sl) < 1 || BUG(smartlist_len(sl) > 2)) { + err_msg = tor_strdup("Bad syntax in hidden service port configuration."); + goto err; + } + virtport = (int)tor_parse_long(smartlist_get(sl,0), 10, 1, 65535, NULL,NULL); + if (!virtport) { + tor_asprintf(&err_msg, "Missing or invalid port %s in hidden service " + "port configuration", escaped(smartlist_get(sl,0))); + + goto err; + } + if (smartlist_len(sl) == 1) { + /* No addr:port part; use default. */ + realport = virtport; + tor_addr_from_ipv4h(&addr, 0x7F000001u); /* 127.0.0.1 */ + } else { + int ret; + + const char *addrport_element = smartlist_get(sl,1); + const char *rest = NULL; + int is_unix; + ret = port_cfg_line_extract_addrport(addrport_element, &addrport, + &is_unix, &rest); + + if (ret < 0) { + tor_asprintf(&err_msg, "Couldn't process address <%s> from hidden " + "service configuration", addrport_element); + goto err; + } + + if (rest && strlen(rest)) { + err_msg = tor_strdup("HiddenServicePort parse error: invalid port " + "mapping"); + goto err; + } + + if (is_unix) { + socket_path = addrport; + is_unix_addr = 1; + } else if (strchr(addrport, ':') || strchr(addrport, '.')) { + /* else try it as an IP:port pair if it has a : or . in it */ + if (tor_addr_port_lookup(addrport, &addr, &p)<0) { + err_msg = tor_strdup("Unparseable address in hidden service port " + "configuration."); + goto err; + } + realport = p?p:virtport; + } else { + /* No addr:port, no addr -- must be port. */ + realport = (int)tor_parse_long(addrport, 10, 1, 65535, NULL, NULL); + if (!realport) { + tor_asprintf(&err_msg, "Unparseable or out-of-range port %s in " + "hidden service port configuration.", + escaped(addrport)); + goto err; + } + tor_addr_from_ipv4h(&addr, 0x7F000001u); /* Default to 127.0.0.1 */ + } + } + + /* Allow room for unix_addr */ + result = rend_service_port_config_new(socket_path); + result->virtual_port = virtport; + result->is_unix_addr = is_unix_addr; + if (!is_unix_addr) { + result->real_port = realport; + tor_addr_copy(&result->real_addr, &addr); + result->unix_addr[0] = '\0'; + } + + err: + tor_free(addrport); + if (err_msg_out != NULL) { + *err_msg_out = err_msg; + } else { + tor_free(err_msg); + } + SMARTLIST_FOREACH(sl, char *, c, tor_free(c)); + smartlist_free(sl); + + return result; +} + +/** Release all storage held in a rend_service_port_config_t. */ +void +rend_service_port_config_free_(rend_service_port_config_t *p) +{ + tor_free(p); +} + +/* Copy relevant data from service src to dst while pruning the service lists. + * This should only be called during the pruning process which takes existing + * services and copy their data to the newly configured services. The src + * service replaycache will be set to NULL after this call. */ +static void +copy_service_on_prunning(rend_service_t *dst, rend_service_t *src) +{ + tor_assert(dst); + tor_assert(src); + + /* Keep the timestamps for when the content changed and the next upload + * time so we can properly upload the descriptor if needed for the new + * service object. */ + dst->desc_is_dirty = src->desc_is_dirty; + dst->next_upload_time = src->next_upload_time; + /* Move the replaycache to the new object. */ + dst->accepted_intro_dh_parts = src->accepted_intro_dh_parts; + src->accepted_intro_dh_parts = NULL; + /* Copy intro point information to destination service. */ + dst->intro_period_started = src->intro_period_started; + dst->n_intro_circuits_launched = src->n_intro_circuits_launched; + dst->n_intro_points_wanted = src->n_intro_points_wanted; +} + +/* Helper: Actual implementation of the pruning on reload which we've + * decoupled in order to make the unit test workeable without ugly hacks. + * Furthermore, this function does NOT free any memory but will nullify the + * temporary list pointer whatever happens. */ +STATIC void +rend_service_prune_list_impl_(void) +{ + origin_circuit_t *ocirc = NULL; + smartlist_t *surviving_services, *old_service_list, *new_service_list; + + /* When pruning our current service list, we must have a staging list that + * contains what we want to check else it's a code flow error. */ + tor_assert(rend_service_staging_list); + + /* We are about to prune the current list of its dead service so set the + * semantic for that list to be the "old" one. */ + old_service_list = rend_service_list; + /* The staging list is now the "new" list so set this semantic. */ + new_service_list = rend_service_staging_list; + /* After this, whatever happens, we'll use our new list. */ + rend_service_list = new_service_list; + /* Finally, nullify the staging list pointer as we don't need it anymore + * and it needs to be NULL before the next reload. */ + rend_service_staging_list = NULL; + /* Nothing to prune if we have no service list so stop right away. */ + if (!old_service_list) { + return; + } + + /* This contains all _existing_ services that survives the relaod that is + * that haven't been removed from the configuration. The difference between + * this list and the new service list is that the new list can possibly + * contain newly configured service that have no introduction points opened + * yet nor key material loaded or generated. */ + surviving_services = smartlist_new(); + + /* Preserve the existing ephemeral services. + * + * This is the ephemeral service equivalent of the "Copy introduction + * points to new services" block, except there's no copy required since + * the service structure isn't regenerated. + * + * After this is done, all ephemeral services will be: + * * Removed from old_service_list, so the equivalent non-ephemeral code + * will not attempt to preserve them. + * * Added to the new_service_list (that previously only had the + * services listed in the configuration). + * * Added to surviving_services, which is the list of services that + * will NOT have their intro point closed. + */ + SMARTLIST_FOREACH_BEGIN(old_service_list, rend_service_t *, old) { + if (rend_service_is_ephemeral(old)) { + SMARTLIST_DEL_CURRENT(old_service_list, old); + smartlist_add(surviving_services, old); + smartlist_add(new_service_list, old); + } + } SMARTLIST_FOREACH_END(old); + + /* Copy introduction points to new services. This is O(n^2), but it's only + * called on reconfigure, so it's ok performance wise. */ + SMARTLIST_FOREACH_BEGIN(new_service_list, rend_service_t *, new) { + SMARTLIST_FOREACH_BEGIN(old_service_list, rend_service_t *, old) { + /* Skip ephemeral services as we only want to copy introduction points + * from current services to newly configured one that already exists. + * The same directory means it's the same service. */ + if (rend_service_is_ephemeral(new) || rend_service_is_ephemeral(old) || + strcmp(old->directory, new->directory)) { + continue; + } + smartlist_add_all(new->intro_nodes, old->intro_nodes); + smartlist_clear(old->intro_nodes); + smartlist_add_all(new->expiring_nodes, old->expiring_nodes); + smartlist_clear(old->expiring_nodes); + + /* Copy needed information from old to new. */ + copy_service_on_prunning(new, old); + + /* This regular service will survive the closing IPs step after. */ + smartlist_add(surviving_services, old); + break; + } SMARTLIST_FOREACH_END(old); + } SMARTLIST_FOREACH_END(new); + + /* For every service introduction circuit we can find, see if we have a + * matching surviving configured service. If not, close the circuit. */ + while ((ocirc = circuit_get_next_intro_circ(ocirc, false))) { + int keep_it = 0; + if (ocirc->rend_data == NULL) { + /* This is a v3 circuit, ignore it. */ + continue; + } + SMARTLIST_FOREACH_BEGIN(surviving_services, const rend_service_t *, s) { + if (rend_circuit_pk_digest_eq(ocirc, (uint8_t *) s->pk_digest)) { + /* Keep this circuit as we have a matching configured service. */ + keep_it = 1; + break; + } + } SMARTLIST_FOREACH_END(s); + if (keep_it) { + continue; + } + log_info(LD_REND, "Closing intro point %s for service %s.", + safe_str_client(extend_info_describe( + ocirc->build_state->chosen_exit)), + safe_str_client(rend_data_get_address(ocirc->rend_data))); + /* 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); + } + smartlist_free(surviving_services); + /* Notify that our global service list has changed. */ + hs_service_map_has_changed(); +} + +/* Try to prune our main service list using the temporary one that we just + * loaded and parsed successfully. The pruning process decides which onion + * services to keep and which to discard after a reload. */ +void +rend_service_prune_list(void) +{ + smartlist_t *old_service_list = rend_service_list; + + if (!rend_service_staging_list) { + rend_service_staging_list = smartlist_new(); + } + + rend_service_prune_list_impl_(); + if (old_service_list) { + /* Every remaining service in the old list have been removed from the + * configuration so clean them up safely. */ + SMARTLIST_FOREACH(old_service_list, rend_service_t *, s, + rend_service_free(s)); + smartlist_free(old_service_list); + } +} + +/* Copy all the relevant data that the hs_service object contains over to the + * rend_service_t object. The reason to do so is because when configuring a + * service, we go through a generic handler that creates an hs_service_t + * object which so we have to copy the parsed values to a rend service object + * which is version 2 specific. */ +static void +service_config_shadow_copy(rend_service_t *service, + hs_service_config_t *config) +{ + tor_assert(service); + tor_assert(config); + + service->directory = tor_strdup(config->directory_path); + service->dir_group_readable = config->dir_group_readable; + service->allow_unknown_ports = config->allow_unknown_ports; + /* This value can't go above HS_CONFIG_MAX_STREAMS_PER_RDV_CIRCUIT (65535) + * if the code flow is right so this cast is safe. But just in case, we'll + * check it. */ + service->max_streams_per_circuit = (int) config->max_streams_per_rdv_circuit; + if (BUG(config->max_streams_per_rdv_circuit > + HS_CONFIG_MAX_STREAMS_PER_RDV_CIRCUIT)) { + service->max_streams_per_circuit = HS_CONFIG_MAX_STREAMS_PER_RDV_CIRCUIT; + } + service->max_streams_close_circuit = config->max_streams_close_circuit; + service->n_intro_points_wanted = config->num_intro_points; + /* Switching ownership of the ports to the rend service object. */ + smartlist_add_all(service->ports, config->ports); + smartlist_free(config->ports); + config->ports = NULL; +} + +/* Parse the hidden service configuration starting at line_ using the + * already configured generic service configuration in config. This + * function will translate the config object to a rend_service_t and add it to + * the temporary list if valid. If validate_only is set, parse, warn + * and return as normal but don't actually add the service to the list. */ +int +rend_config_service(const config_line_t *line_, + const or_options_t *options, + hs_service_config_t *config) +{ + const config_line_t *line; + rend_service_t *service = NULL; + + /* line_ can be NULL which would mean that the service configuration only + * have one line that is the directory directive. */ + tor_assert(options); + tor_assert(config); + + /* Use the staging service list so that we can check then do the pruning + * process using the main list at the end. */ + if (rend_service_staging_list == NULL) { + rend_service_staging_list = smartlist_new(); + } + + /* Initialize service. */ + service = tor_malloc_zero(sizeof(rend_service_t)); + service->intro_period_started = time(NULL); + service->ports = smartlist_new(); + /* From the hs_service object which has been used to load the generic + * options, we'll copy over the useful data to the rend_service_t object. */ + service_config_shadow_copy(service, config); + + for (line = line_; line; line = line->next) { + if (!strcasecmp(line->key, "HiddenServiceDir")) { + /* We just hit the next hidden service, stop right now. */ + break; + } + /* Number of introduction points. */ + if (!strcasecmp(line->key, "HiddenServiceNumIntroductionPoints")) { + int ok = 0; + /* Those are specific defaults for version 2. */ + service->n_intro_points_wanted = + (unsigned int) tor_parse_long(line->value, 10, + 0, NUM_INTRO_POINTS_MAX, &ok, NULL); + if (!ok) { + log_warn(LD_CONFIG, + "HiddenServiceNumIntroductionPoints " + "should be between %d and %d, not %s", + 0, NUM_INTRO_POINTS_MAX, line->value); + goto err; + } + log_info(LD_CONFIG, "HiddenServiceNumIntroductionPoints=%d for %s", + service->n_intro_points_wanted, escaped(service->directory)); + continue; + } + if (!strcasecmp(line->key, "HiddenServiceAuthorizeClient")) { + /* Parse auth type and comma-separated list of client names and add a + * rend_authorized_client_t for each client to the service's list + * of authorized clients. */ + smartlist_t *type_names_split, *clients; + const char *authname; + if (service->auth_type != REND_NO_AUTH) { + log_warn(LD_CONFIG, "Got multiple HiddenServiceAuthorizeClient " + "lines for a single service."); + goto err; + } + type_names_split = smartlist_new(); + smartlist_split_string(type_names_split, line->value, " ", 0, 2); + if (smartlist_len(type_names_split) < 1) { + log_warn(LD_BUG, "HiddenServiceAuthorizeClient has no value. This " + "should have been prevented when parsing the " + "configuration."); + smartlist_free(type_names_split); + goto err; + } + authname = smartlist_get(type_names_split, 0); + if (!strcasecmp(authname, "basic")) { + service->auth_type = REND_BASIC_AUTH; + } else if (!strcasecmp(authname, "stealth")) { + service->auth_type = REND_STEALTH_AUTH; + } else { + log_warn(LD_CONFIG, "HiddenServiceAuthorizeClient contains " + "unrecognized auth-type '%s'. Only 'basic' or 'stealth' " + "are recognized.", + (char *) smartlist_get(type_names_split, 0)); + SMARTLIST_FOREACH(type_names_split, char *, cp, tor_free(cp)); + smartlist_free(type_names_split); + goto err; + } + service->clients = smartlist_new(); + if (smartlist_len(type_names_split) < 2) { + log_warn(LD_CONFIG, "HiddenServiceAuthorizeClient contains " + "auth-type '%s', but no client names.", + service->auth_type == REND_BASIC_AUTH ? "basic" : "stealth"); + SMARTLIST_FOREACH(type_names_split, char *, cp, tor_free(cp)); + smartlist_free(type_names_split); + continue; + } + clients = smartlist_new(); + smartlist_split_string(clients, smartlist_get(type_names_split, 1), + ",", SPLIT_SKIP_SPACE, 0); + SMARTLIST_FOREACH(type_names_split, char *, cp, tor_free(cp)); + smartlist_free(type_names_split); + /* Remove duplicate client names. */ + { + int num_clients = smartlist_len(clients); + smartlist_sort_strings(clients); + smartlist_uniq_strings(clients); + if (smartlist_len(clients) < num_clients) { + log_info(LD_CONFIG, "HiddenServiceAuthorizeClient contains %d " + "duplicate client name(s); removing.", + num_clients - smartlist_len(clients)); + } + } + SMARTLIST_FOREACH_BEGIN(clients, const char *, client_name) + { + rend_authorized_client_t *client; + if (!rend_valid_client_name(client_name)) { + log_warn(LD_CONFIG, "HiddenServiceAuthorizeClient contains an " + "illegal client name: '%s'. Names must be " + "between 1 and %d characters and contain " + "only [A-Za-z0-9+_-].", + client_name, REND_CLIENTNAME_MAX_LEN); + SMARTLIST_FOREACH(clients, char *, cp, tor_free(cp)); + smartlist_free(clients); + goto err; + } + client = tor_malloc_zero(sizeof(rend_authorized_client_t)); + client->client_name = tor_strdup(client_name); + smartlist_add(service->clients, client); + log_debug(LD_REND, "Adding client name '%s'", client_name); + } + SMARTLIST_FOREACH_END(client_name); + SMARTLIST_FOREACH(clients, char *, cp, tor_free(cp)); + smartlist_free(clients); + /* Ensure maximum number of clients. */ + if ((service->auth_type == REND_BASIC_AUTH && + smartlist_len(service->clients) > 512) || + (service->auth_type == REND_STEALTH_AUTH && + smartlist_len(service->clients) > 16)) { + log_warn(LD_CONFIG, "HiddenServiceAuthorizeClient contains %d " + "client authorization entries, but only a " + "maximum of %d entries is allowed for " + "authorization type '%s'.", + smartlist_len(service->clients), + service->auth_type == REND_BASIC_AUTH ? 512 : 16, + service->auth_type == REND_BASIC_AUTH ? "basic" : "stealth"); + goto err; + } + continue; + } + } + /* Validate the service just parsed. */ + if (rend_validate_service(rend_service_staging_list, service) < 0) { + /* Service is in the staging list so don't try to free it. */ + goto err; + } + + /* Add it to the temporary list which we will use to prune our current + * list if any after configuring all services. */ + if (rend_add_service(rend_service_staging_list, service) < 0) { + /* The object has been freed on error already. */ + service = NULL; + goto err; + } + + return 0; + err: + rend_service_free(service); + return -1; +} + +/** Add the ephemeral service pk/ports if possible, using + * client authorization auth_type and an optional list of + * rend_authorized_client_t in auth_clients, with + * max_streams_per_circuit streams allowed per rendezvous circuit, + * and circuit closure on max streams being exceeded set by + * max_streams_close_circuit. + * + * Ownership of pk, ports, and auth_clients is passed to this routine. + * Regardless of success/failure, callers should not touch these values + * after calling this routine, and may assume that correct cleanup has + * been done on failure. + * + * Return an appropriate hs_service_add_ephemeral_status_t. + */ +hs_service_add_ephemeral_status_t +rend_service_add_ephemeral(crypto_pk_t *pk, + smartlist_t *ports, + int max_streams_per_circuit, + int max_streams_close_circuit, + rend_auth_type_t auth_type, + smartlist_t *auth_clients, + char **service_id_out) +{ + *service_id_out = NULL; + /* Allocate the service structure, and initialize the key, and key derived + * parameters. + */ + rend_service_t *s = tor_malloc_zero(sizeof(rend_service_t)); + s->directory = NULL; /* This indicates the service is ephemeral. */ + s->private_key = pk; + s->auth_type = auth_type; + s->clients = auth_clients; + s->ports = ports; + s->intro_period_started = time(NULL); + s->n_intro_points_wanted = NUM_INTRO_POINTS_DEFAULT; + s->max_streams_per_circuit = max_streams_per_circuit; + s->max_streams_close_circuit = max_streams_close_circuit; + if (rend_service_derive_key_digests(s) < 0) { + rend_service_free(s); + return RSAE_BADPRIVKEY; + } + + if (!s->ports || smartlist_len(s->ports) == 0) { + log_warn(LD_CONFIG, "At least one VIRTPORT/TARGET must be specified."); + rend_service_free(s); + return RSAE_BADVIRTPORT; + } + if (s->auth_type != REND_NO_AUTH && + (!s->clients || smartlist_len(s->clients) == 0)) { + log_warn(LD_CONFIG, "At least one authorized client must be specified."); + rend_service_free(s); + return RSAE_BADAUTH; + } + + /* Enforcing pk/id uniqueness should be done by rend_service_load_keys(), but + * it's not, see #14828. + */ + if (rend_service_get_by_pk_digest(s->pk_digest)) { + log_warn(LD_CONFIG, "Onion Service private key collides with an " + "existing service."); + rend_service_free(s); + return RSAE_ADDREXISTS; + } + if (rend_service_get_by_service_id(s->service_id)) { + log_warn(LD_CONFIG, "Onion Service id collides with an existing service."); + rend_service_free(s); + return RSAE_ADDREXISTS; + } + + /* Initialize the service. */ + if (rend_add_service(NULL, s)) { + return RSAE_INTERNAL; + } + *service_id_out = tor_strdup(s->service_id); + + log_debug(LD_CONFIG, "Added ephemeral Onion Service: %s", s->service_id); + return RSAE_OKAY; +} + +/** Remove the ephemeral service service_id if possible. Returns 0 on + * success, and -1 on failure. + */ +int +rend_service_del_ephemeral(const char *service_id) +{ + rend_service_t *s; + if (!rend_valid_v2_service_id(service_id)) { + log_warn(LD_CONFIG, "Requested malformed Onion Service id for removal."); + return -1; + } + if ((s = rend_service_get_by_service_id(service_id)) == NULL) { + log_warn(LD_CONFIG, "Requested non-existent Onion Service id for " + "removal."); + return -1; + } + if (!rend_service_is_ephemeral(s)) { + log_warn(LD_CONFIG, "Requested non-ephemeral Onion Service for removal."); + return -1; + } + + /* Kill the intro point circuit for the Onion Service, and remove it from + * the list. Closing existing connections is the application's problem. + * + * XXX: As with the comment in rend_config_services(), a nice abstraction + * would be ideal here, but for now just duplicate the code. + */ + SMARTLIST_FOREACH_BEGIN(circuit_get_global_list(), circuit_t *, circ) { + if (!circ->marked_for_close && + (circ->purpose == CIRCUIT_PURPOSE_S_ESTABLISH_INTRO || + circ->purpose == CIRCUIT_PURPOSE_S_INTRO)) { + origin_circuit_t *oc = TO_ORIGIN_CIRCUIT(circ); + if (oc->rend_data == NULL || + !rend_circuit_pk_digest_eq(oc, (uint8_t *) s->pk_digest)) { + continue; + } + log_debug(LD_REND, "Closing intro point %s for service %s.", + safe_str_client(extend_info_describe( + oc->build_state->chosen_exit)), + rend_data_get_address(oc->rend_data)); + circuit_mark_for_close(circ, END_CIRC_REASON_FINISHED); + } + } SMARTLIST_FOREACH_END(circ); + smartlist_remove(rend_service_list, s); + /* Notify that we just removed a service from our global list. */ + hs_service_map_has_changed(); + rend_service_free(s); + + log_debug(LD_CONFIG, "Removed ephemeral Onion Service: %s", service_id); + + return 0; +} + +/* There can be 1 second's delay due to second_elapsed_callback, and perhaps + * another few seconds due to blocking calls. */ +#define INTRO_CIRC_RETRY_PERIOD_SLOP 10 + +/** Log information about the intro point creation rate and current intro + * points for service, upgrading the log level from min_severity to warn if + * we have stopped launching new intro point circuits. */ +static void +rend_log_intro_limit(const rend_service_t *service, int min_severity) +{ + int exceeded_limit = (service->n_intro_circuits_launched >= + rend_max_intro_circs_per_period( + service->n_intro_points_wanted)); + int severity = min_severity; + /* We stopped creating circuits */ + if (exceeded_limit) { + severity = LOG_WARN; + } + time_t intro_period_elapsed = time(NULL) - service->intro_period_started; + tor_assert_nonfatal(intro_period_elapsed >= 0); + { + char *msg; + static ratelim_t rlimit = RATELIM_INIT(INTRO_CIRC_RETRY_PERIOD); + if ((msg = rate_limit_log(&rlimit, approx_time()))) { + log_fn(severity, LD_REND, + "Hidden service %s %s %d intro points in the last %d seconds. " + "Intro circuit launches are limited to %d per %d seconds.%s", + service->service_id, + exceeded_limit ? "exceeded launch limit with" : "launched", + service->n_intro_circuits_launched, + (int)intro_period_elapsed, + rend_max_intro_circs_per_period(service->n_intro_points_wanted), + INTRO_CIRC_RETRY_PERIOD, msg); + rend_service_dump_stats(severity); + tor_free(msg); + } + } +} + +/** Replace the old value of service-\>desc with one that reflects + * the other fields in service. + */ +static void +rend_service_update_descriptor(rend_service_t *service) +{ + rend_service_descriptor_t *d; + int i; + + rend_service_descriptor_free(service->desc); + service->desc = NULL; + + d = service->desc = tor_malloc_zero(sizeof(rend_service_descriptor_t)); + d->pk = crypto_pk_dup_key(service->private_key); + d->timestamp = time(NULL); + d->timestamp -= d->timestamp % 3600; /* Round down to nearest hour */ + d->intro_nodes = smartlist_new(); + /* Support intro protocols 2 and 3. */ + d->protocols = (1 << 2) + (1 << 3); + + for (i = 0; i < smartlist_len(service->intro_nodes); ++i) { + rend_intro_point_t *intro_svc = smartlist_get(service->intro_nodes, i); + rend_intro_point_t *intro_desc; + + /* This intro point won't be listed in the descriptor... */ + intro_svc->listed_in_last_desc = 0; + + /* circuit_established is set in rend_service_intro_established(), and + * checked every second in rend_consider_services_intro_points(), so it's + * safe to use it here */ + if (!intro_svc->circuit_established) { + continue; + } + + /* ...unless this intro point is listed in the descriptor. */ + intro_svc->listed_in_last_desc = 1; + + /* We have an entirely established intro circuit. Publish it in + * our descriptor. */ + intro_desc = tor_malloc_zero(sizeof(rend_intro_point_t)); + intro_desc->extend_info = extend_info_dup(intro_svc->extend_info); + if (intro_svc->intro_key) + intro_desc->intro_key = crypto_pk_dup_key(intro_svc->intro_key); + smartlist_add(d->intro_nodes, intro_desc); + + if (intro_svc->time_published == -1) { + /* We are publishing this intro point in a descriptor for the + * first time -- note the current time in the service's copy of + * the intro point. */ + intro_svc->time_published = time(NULL); + } + } + + /* Check that we have the right number of intro points */ + unsigned int have_intro = (unsigned int)smartlist_len(d->intro_nodes); + if (have_intro != service->n_intro_points_wanted) { + int severity; + /* Getting less than we wanted or more than we're allowed is serious */ + if (have_intro < service->n_intro_points_wanted || + have_intro > NUM_INTRO_POINTS_MAX) { + severity = LOG_WARN; + } else { + /* Getting more than we wanted is weird, but less of a problem */ + severity = LOG_NOTICE; + } + log_fn(severity, LD_REND, "Hidden service %s wanted %d intro points, but " + "descriptor was updated with %d instead.", + service->service_id, + service->n_intro_points_wanted, have_intro); + /* Now log an informative message about how we might have got here. */ + rend_log_intro_limit(service, severity); + } +} + +/* Allocate and return a string containing the path to file_name in + * service->directory. Asserts that service has a directory. + * This function will never return NULL. + * The caller must free this path. */ +static char * +rend_service_path(const rend_service_t *service, const char *file_name) +{ + tor_assert(service->directory); + return hs_path_from_filename(service->directory, file_name); +} + +/* Allocate and return a string containing the path to the single onion + * service poison file in service->directory. Asserts that service has a + * directory. + * The caller must free this path. */ +STATIC char * +rend_service_sos_poison_path(const rend_service_t *service) +{ + return rend_service_path(service, sos_poison_fname); +} + +/** Return True if hidden services service has been poisoned by single + * onion mode. */ +static int +service_is_single_onion_poisoned(const rend_service_t *service) +{ + char *poison_fname = NULL; + file_status_t fstatus; + + /* Passing a NULL service is a bug */ + if (BUG(!service)) { + return 0; + } + + if (rend_service_is_ephemeral(service)) { + return 0; + } + + poison_fname = rend_service_sos_poison_path(service); + + fstatus = file_status(poison_fname); + tor_free(poison_fname); + + /* If this fname is occupied, the hidden service has been poisoned. + * fstatus can be FN_ERROR if the service directory does not exist, in that + * case, there is obviously no private key. */ + if (fstatus == FN_FILE || fstatus == FN_EMPTY) { + return 1; + } + + return 0; +} + +/* Return 1 if the private key file for service exists and has a non-zero size, + * and 0 otherwise. */ +static int +rend_service_private_key_exists(const rend_service_t *service) +{ + char *private_key_path = rend_service_path(service, private_key_fname); + const file_status_t private_key_status = file_status(private_key_path); + tor_free(private_key_path); + /* Only non-empty regular private key files could have been used before. + * fstatus can be FN_ERROR if the service directory does not exist, in that + * case, there is obviously no private key. */ + return private_key_status == FN_FILE; +} + +/** Check the single onion service poison state of the directory for s: + * - If the service is poisoned, and we are in Single Onion Mode, + * return 0, + * - If the service is not poisoned, and we are not in Single Onion Mode, + * return 0, + * - Otherwise, the poison state is invalid: the service was created in one + * mode, and is being used in the other, return -1. + * Hidden service directories without keys are always considered consistent. + * They will be poisoned after their directory is created (if needed). */ +STATIC int +rend_service_verify_single_onion_poison(const rend_service_t* s, + const or_options_t* options) +{ + /* Passing a NULL service is a bug */ + if (BUG(!s)) { + return -1; + } + + /* Ephemeral services are checked at ADD_ONION time */ + if (BUG(rend_service_is_ephemeral(s))) { + return -1; + } + + /* Service is expected to have a directory */ + if (BUG(!s->directory)) { + return -1; + } + + /* Services without keys are always ok - their keys will only ever be used + * in the current mode */ + if (!rend_service_private_key_exists(s)) { + return 0; + } + + /* The key has been used before in a different mode */ + if (service_is_single_onion_poisoned(s) != + rend_service_non_anonymous_mode_enabled(options)) { + return -1; + } + + /* The key exists and is consistent with the current mode */ + return 0; +} + +/*** Helper for rend_service_poison_new_single_onion_dir(). Add a file to + * the hidden service directory for s that marks it as a single onion service. + * Tor must be in single onion mode before calling this function, and the + * service directory must already have been created. + * Returns 0 when a directory is successfully poisoned, or if it is already + * poisoned. Returns -1 on a failure to read the directory or write the poison + * file, or if there is an existing private key file in the directory. (The + * service should have been poisoned when the key was created.) */ +static int +poison_new_single_onion_hidden_service_dir_impl(const rend_service_t *service, + const or_options_t* options) +{ + /* Passing a NULL service is a bug */ + if (BUG(!service)) { + return -1; + } + + /* We must only poison directories if we're in Single Onion mode */ + tor_assert(rend_service_non_anonymous_mode_enabled(options)); + + int fd; + int retval = -1; + char *poison_fname = NULL; + + if (rend_service_is_ephemeral(service)) { + log_info(LD_REND, "Ephemeral HS started in non-anonymous mode."); + return 0; + } + + /* Make sure we're only poisoning new hidden service directories */ + if (rend_service_private_key_exists(service)) { + log_warn(LD_BUG, "Tried to single onion poison a service directory after " + "the private key was created."); + return -1; + } + + /* Make sure the directory was created before calling this function. */ + if (BUG(hs_check_service_private_dir(options->User, service->directory, + service->dir_group_readable, 0) < 0)) + return -1; + + poison_fname = rend_service_sos_poison_path(service); + + switch (file_status(poison_fname)) { + case FN_DIR: + case FN_ERROR: + log_warn(LD_FS, "Can't read single onion poison file \"%s\"", + poison_fname); + goto done; + case FN_FILE: /* single onion poison file already exists. NOP. */ + case FN_EMPTY: /* single onion poison file already exists. NOP. */ + log_debug(LD_FS, "Tried to re-poison a single onion poisoned file \"%s\"", + poison_fname); + break; + case FN_NOENT: + fd = tor_open_cloexec(poison_fname, O_RDWR|O_CREAT|O_TRUNC, 0600); + if (fd < 0) { + log_warn(LD_FS, "Could not create single onion poison file %s", + poison_fname); + goto done; + } + close(fd); + break; + default: + tor_assert(0); + } + + retval = 0; + + done: + tor_free(poison_fname); + + return retval; +} + +/** We just got launched in Single Onion Mode. That's a non-anonymous mode for + * hidden services. If s is new, we should mark its hidden service + * directory appropriately so that it is never launched as a location-private + * hidden service. (New directories don't have private key files.) + * Return 0 on success, -1 on fail. */ +STATIC int +rend_service_poison_new_single_onion_dir(const rend_service_t *s, + const or_options_t* options) +{ + /* Passing a NULL service is a bug */ + if (BUG(!s)) { + return -1; + } + + /* We must only poison directories if we're in Single Onion mode */ + tor_assert(rend_service_non_anonymous_mode_enabled(options)); + + /* Ephemeral services aren't allowed in non-anonymous mode */ + if (BUG(rend_service_is_ephemeral(s))) { + return -1; + } + + /* Service is expected to have a directory */ + if (BUG(!s->directory)) { + return -1; + } + + if (!rend_service_private_key_exists(s)) { + if (poison_new_single_onion_hidden_service_dir_impl(s, options) + < 0) { + return -1; + } + } + + return 0; +} + +/* Return true iff the given service identity key is present on disk. This is + * used to try to learn the service version during configuration time. */ +int +rend_service_key_on_disk(const char *directory_path) +{ + int ret = 0; + char *fname; + crypto_pk_t *pk = NULL; + + tor_assert(directory_path); + + /* Load key */ + fname = hs_path_from_filename(directory_path, private_key_fname); + pk = init_key_from_file(fname, 0, LOG_DEBUG, NULL); + if (pk) { + ret = 1; + } + + crypto_pk_free(pk); + tor_free(fname); + return ret; +} + +/** Load and/or generate private keys for all hidden services, possibly + * including keys for client authorization. + * If a service_list is provided, treat it as the list of hidden + * services (used in unittests). Otherwise, require that rend_service_list is + * not NULL. + * Return 0 on success, -1 on failure. */ +int +rend_service_load_all_keys(const smartlist_t *service_list) +{ + /* Use service_list for unit tests */ + const smartlist_t *s_list = rend_get_service_list(service_list); + if (BUG(!s_list)) { + return -1; + } + + SMARTLIST_FOREACH_BEGIN(s_list, rend_service_t *, s) { + if (s->private_key) + continue; + log_info(LD_REND, "Loading hidden-service keys from %s", + rend_service_escaped_dir(s)); + + if (rend_service_load_keys(s) < 0) + return -1; + } SMARTLIST_FOREACH_END(s); + + return 0; +} + +/** Add to lst every filename used by s. */ +static void +rend_service_add_filenames_to_list(smartlist_t *lst, const rend_service_t *s) +{ + tor_assert(lst); + tor_assert(s); + tor_assert(s->directory); + smartlist_add(lst, rend_service_path(s, private_key_fname)); + smartlist_add(lst, rend_service_path(s, hostname_fname)); + smartlist_add(lst, rend_service_path(s, client_keys_fname)); + smartlist_add(lst, rend_service_sos_poison_path(s)); +} + +/** Add to open_lst every filename used by a configured hidden service, + * and to stat_lst every directory used by a configured hidden + * service */ +void +rend_services_add_filenames_to_lists(smartlist_t *open_lst, + smartlist_t *stat_lst) +{ + if (!rend_service_list) + return; + SMARTLIST_FOREACH_BEGIN(rend_service_list, rend_service_t *, s) { + if (!rend_service_is_ephemeral(s)) { + rend_service_add_filenames_to_list(open_lst, s); + smartlist_add_strdup(stat_lst, s->directory); + } + } SMARTLIST_FOREACH_END(s); +} + +/** Derive all rend_service_t internal material based on the service's key. + * Returns 0 on success, -1 on failure. + */ +static int +rend_service_derive_key_digests(struct rend_service_t *s) +{ + if (rend_get_service_id(s->private_key, s->service_id)<0) { + log_warn(LD_BUG, "Internal error: couldn't encode service ID."); + return -1; + } + if (crypto_pk_get_digest(s->private_key, s->pk_digest)<0) { + log_warn(LD_BUG, "Couldn't compute hash of public key."); + return -1; + } + + return 0; +} + +/** Make sure that the directory for s is private, using the config in + * options. + * If create is true: + * - if the directory exists, change permissions if needed, + * - if the directory does not exist, create it with the correct permissions. + * If create is false: + * - if the directory exists, check permissions, + * - if the directory does not exist, check if we think we can create it. + * Return 0 on success, -1 on failure. */ +static int +rend_service_check_private_dir(const or_options_t *options, + const rend_service_t *s, + int create) +{ + /* Passing a NULL service is a bug */ + if (BUG(!s)) { + return -1; + } + + /* Check/create directory */ + if (hs_check_service_private_dir(options->User, s->directory, + s->dir_group_readable, create) < 0) { + return -1; + } + + /* Check if the hidden service key exists, and was created in a different + * single onion service mode, and refuse to launch if it has. + * This is safe to call even when create is false, as it ignores missing + * keys and directories: they are always valid. + */ + if (rend_service_verify_single_onion_poison(s, options) < 0) { + /* We can't use s->service_id here, as the key may not have been loaded */ + log_warn(LD_GENERAL, "We are configured with " + "HiddenServiceNonAnonymousMode %d, but the hidden " + "service key in directory %s was created in %s mode. " + "This is not allowed.", + rend_service_non_anonymous_mode_enabled(options) ? 1 : 0, + rend_service_escaped_dir(s), + rend_service_non_anonymous_mode_enabled(options) ? + "an anonymous" : "a non-anonymous" + ); + return -1; + } + + /* Poison new single onion directories immediately after they are created, + * so that we never accidentally launch non-anonymous hidden services + * thinking they are anonymous. Any keys created later will end up with the + * correct poisoning state. + */ + if (create && rend_service_non_anonymous_mode_enabled(options)) { + static int logged_warning = 0; + + if (rend_service_poison_new_single_onion_dir(s, options) < 0) { + log_warn(LD_GENERAL,"Failed to mark new hidden services as non-anonymous" + "."); + return -1; + } + + if (!logged_warning) { + /* The keys for these services are linked to the server IP address */ + log_notice(LD_REND, "The configured onion service directories have been " + "used in single onion mode. They can not be used for " + "anonymous hidden services."); + logged_warning = 1; + } + } + + return 0; +} + +/** Load and/or generate private keys for the hidden service s, + * possibly including keys for client authorization. Return 0 on success, -1 + * on failure. */ +static int +rend_service_load_keys(rend_service_t *s) +{ + char *fname = NULL; + char buf[128]; + + /* Create the directory if needed which will also poison it in case of + * single onion service. */ + if (rend_service_check_private_dir(get_options(), s, 1) < 0) + goto err; + + /* Load key */ + fname = rend_service_path(s, private_key_fname); + s->private_key = init_key_from_file(fname, 1, LOG_ERR, NULL); + + if (!s->private_key) + goto err; + + if (rend_service_derive_key_digests(s) < 0) + goto err; + + tor_free(fname); + /* Create service file */ + fname = rend_service_path(s, hostname_fname); + + tor_snprintf(buf, sizeof(buf),"%s.onion\n", s->service_id); + if (write_str_to_file(fname,buf,0)<0) { + log_warn(LD_CONFIG, "Could not write onion address to hostname file."); + goto err; + } +#ifndef _WIN32 + if (s->dir_group_readable) { + /* Also verify hostname file created with group read. */ + if (chmod(fname, 0640)) + log_warn(LD_FS,"Unable to make hidden hostname file %s group-readable.", + fname); + } +#endif /* !defined(_WIN32) */ + + /* If client authorization is configured, load or generate keys. */ + if (s->auth_type != REND_NO_AUTH) { + if (rend_service_load_auth_keys(s, fname) < 0) { + goto err; + } + } + + int r = 0; + goto done; + err: + r = -1; + done: + memwipe(buf, 0, sizeof(buf)); + tor_free(fname); + return r; +} + +/** Load and/or generate client authorization keys for the hidden service + * s, which stores its hostname in hfname. Return 0 on success, + * -1 on failure. */ +static int +rend_service_load_auth_keys(rend_service_t *s, const char *hfname) +{ + int r = 0; + char *cfname = NULL; + char *client_keys_str = NULL; + strmap_t *parsed_clients = strmap_new(); + FILE *cfile, *hfile; + open_file_t *open_cfile = NULL, *open_hfile = NULL; + char desc_cook_out[3*REND_DESC_COOKIE_LEN_BASE64+1]; + char service_id[16+1]; + char buf[1500]; + + /* Load client keys and descriptor cookies, if available. */ + cfname = rend_service_path(s, client_keys_fname); + client_keys_str = read_file_to_str(cfname, RFTS_IGNORE_MISSING, NULL); + if (client_keys_str) { + if (rend_parse_client_keys(parsed_clients, client_keys_str) < 0) { + log_warn(LD_CONFIG, "Previously stored client_keys file could not " + "be parsed."); + goto err; + } else { + log_info(LD_CONFIG, "Parsed %d previously stored client entries.", + strmap_size(parsed_clients)); + } + } + + /* Prepare client_keys and hostname files. */ + if (!(cfile = start_writing_to_stdio_file(cfname, + OPEN_FLAGS_REPLACE | O_TEXT, + 0600, &open_cfile))) { + log_warn(LD_CONFIG, "Could not open client_keys file %s", + escaped(cfname)); + goto err; + } + + if (!(hfile = start_writing_to_stdio_file(hfname, + OPEN_FLAGS_REPLACE | O_TEXT, + 0600, &open_hfile))) { + log_warn(LD_CONFIG, "Could not open hostname file %s", escaped(hfname)); + goto err; + } + + /* Either use loaded keys for configured clients or generate new + * ones if a client is new. */ + SMARTLIST_FOREACH_BEGIN(s->clients, rend_authorized_client_t *, client) { + rend_authorized_client_t *parsed = + strmap_get(parsed_clients, client->client_name); + int written; + size_t len; + /* Copy descriptor cookie from parsed entry or create new one. */ + if (parsed) { + memcpy(client->descriptor_cookie, parsed->descriptor_cookie, + REND_DESC_COOKIE_LEN); + } else { + crypto_rand((char *) client->descriptor_cookie, REND_DESC_COOKIE_LEN); + } + /* For compatibility with older tor clients, this does not + * truncate the padding characters, unlike rend_auth_encode_cookie. */ + if (base64_encode(desc_cook_out, 3*REND_DESC_COOKIE_LEN_BASE64+1, + (char *) client->descriptor_cookie, + REND_DESC_COOKIE_LEN, 0) < 0) { + log_warn(LD_BUG, "Could not base64-encode descriptor cookie."); + goto err; + } + /* Copy client key from parsed entry or create new one if required. */ + if (parsed && parsed->client_key) { + client->client_key = crypto_pk_dup_key(parsed->client_key); + } else if (s->auth_type == REND_STEALTH_AUTH) { + /* Create private key for client. */ + crypto_pk_t *prkey = NULL; + if (!(prkey = crypto_pk_new())) { + log_warn(LD_BUG,"Error constructing client key"); + goto err; + } + if (crypto_pk_generate_key(prkey)) { + log_warn(LD_BUG,"Error generating client key"); + crypto_pk_free(prkey); + goto err; + } + if (! crypto_pk_is_valid_private_key(prkey)) { + log_warn(LD_BUG,"Generated client key seems invalid"); + crypto_pk_free(prkey); + goto err; + } + client->client_key = prkey; + } + /* Add entry to client_keys file. */ + written = tor_snprintf(buf, sizeof(buf), + "client-name %s\ndescriptor-cookie %s\n", + client->client_name, desc_cook_out); + if (written < 0) { + log_warn(LD_BUG, "Could not write client entry."); + goto err; + } + if (client->client_key) { + char *client_key_out = NULL; + if (crypto_pk_write_private_key_to_string(client->client_key, + &client_key_out, &len) != 0) { + log_warn(LD_BUG, "Internal error: " + "crypto_pk_write_private_key_to_string() failed."); + goto err; + } + if (rend_get_service_id(client->client_key, service_id)<0) { + log_warn(LD_BUG, "Internal error: couldn't encode service ID."); + /* + * len is string length, not buffer length, but last byte is NUL + * anyway. + */ + memwipe(client_key_out, 0, len); + tor_free(client_key_out); + goto err; + } + written = tor_snprintf(buf + written, sizeof(buf) - written, + "client-key\n%s", client_key_out); + memwipe(client_key_out, 0, len); + tor_free(client_key_out); + if (written < 0) { + log_warn(LD_BUG, "Could not write client entry."); + goto err; + } + } else { + strlcpy(service_id, s->service_id, sizeof(service_id)); + } + + if (fputs(buf, cfile) < 0) { + log_warn(LD_FS, "Could not append client entry to file: %s", + strerror(errno)); + goto err; + } + + /* Add line to hostname file. This is not the same encoding as in + * client_keys. */ + char *encoded_cookie = rend_auth_encode_cookie(client->descriptor_cookie, + s->auth_type); + if (!encoded_cookie) { + log_warn(LD_BUG, "Could not base64-encode descriptor cookie."); + goto err; + } + tor_snprintf(buf, sizeof(buf), "%s.onion %s # client: %s\n", + service_id, encoded_cookie, client->client_name); + memwipe(encoded_cookie, 0, strlen(encoded_cookie)); + tor_free(encoded_cookie); + + if (fputs(buf, hfile)<0) { + log_warn(LD_FS, "Could not append host entry to file: %s", + strerror(errno)); + goto err; + } + } SMARTLIST_FOREACH_END(client); + + finish_writing_to_file(open_cfile); + finish_writing_to_file(open_hfile); + + goto done; + err: + r = -1; + if (open_cfile) + abort_writing_to_file(open_cfile); + if (open_hfile) + abort_writing_to_file(open_hfile); + done: + if (client_keys_str) { + memwipe(client_keys_str, 0, strlen(client_keys_str)); + tor_free(client_keys_str); + } + strmap_free(parsed_clients, rend_authorized_client_free_void); + + if (cfname) { + memwipe(cfname, 0, strlen(cfname)); + tor_free(cfname); + } + + /* Clear stack buffers that held key-derived material. */ + memwipe(buf, 0, sizeof(buf)); + memwipe(desc_cook_out, 0, sizeof(desc_cook_out)); + memwipe(service_id, 0, sizeof(service_id)); + + return r; +} + +/** Return the service whose public key has a digest of digest, or + * NULL if no such service exists. + */ +static rend_service_t * +rend_service_get_by_pk_digest(const char* digest) +{ + SMARTLIST_FOREACH(rend_service_list, rend_service_t*, s, + if (tor_memeq(s->pk_digest,digest,DIGEST_LEN)) + return s); + return NULL; +} + +/** Return the service whose service id is id, or NULL if no such + * service exists. + */ +static struct rend_service_t * +rend_service_get_by_service_id(const char *id) +{ + tor_assert(strlen(id) == REND_SERVICE_ID_LEN_BASE32); + SMARTLIST_FOREACH(rend_service_list, rend_service_t*, s, { + if (tor_memeq(s->service_id, id, REND_SERVICE_ID_LEN_BASE32)) + return s; + }); + return NULL; +} + +/** Check client authorization of a given descriptor_cookie of + * length cookie_len for service. Return 1 for success + * and 0 for failure. */ +static int +rend_check_authorization(rend_service_t *service, + const char *descriptor_cookie, + size_t cookie_len) +{ + rend_authorized_client_t *auth_client = NULL; + tor_assert(service); + tor_assert(descriptor_cookie); + if (!service->clients) { + log_warn(LD_BUG, "Can't check authorization for a service that has no " + "authorized clients configured."); + return 0; + } + + if (cookie_len != REND_DESC_COOKIE_LEN) { + log_info(LD_REND, "Descriptor cookie is %lu bytes, but we expected " + "%lu bytes. Dropping cell.", + (unsigned long)cookie_len, (unsigned long)REND_DESC_COOKIE_LEN); + return 0; + } + + /* Look up client authorization by descriptor cookie. */ + SMARTLIST_FOREACH(service->clients, rend_authorized_client_t *, client, { + if (tor_memeq(client->descriptor_cookie, descriptor_cookie, + REND_DESC_COOKIE_LEN)) { + auth_client = client; + break; + } + }); + if (!auth_client) { + char descriptor_cookie_base64[3*REND_DESC_COOKIE_LEN_BASE64]; + base64_encode(descriptor_cookie_base64, sizeof(descriptor_cookie_base64), + descriptor_cookie, REND_DESC_COOKIE_LEN, 0); + log_info(LD_REND, "No authorization found for descriptor cookie '%s'! " + "Dropping cell!", + descriptor_cookie_base64); + return 0; + } + + /* Allow the request. */ + log_info(LD_REND, "Client %s authorized for service %s.", + auth_client->client_name, service->service_id); + return 1; +} + +/* Can this service make a direct connection to ei? + * It must be a single onion service, and the firewall rules must allow ei. */ +static int +rend_service_use_direct_connection(const or_options_t* options, + const extend_info_t* ei) +{ + /* We'll connect directly all reachable addresses, whether preferred or not. + * The prefer_ipv6 argument to fascist_firewall_allows_address_addr is + * ignored, because pref_only is 0. */ + return (rend_service_allow_non_anonymous_connection(options) && + fascist_firewall_allows_address_addr(&ei->addr, ei->port, + FIREWALL_OR_CONNECTION, 0, 0)); +} + +/* Like rend_service_use_direct_connection, but to a node. */ +static int +rend_service_use_direct_connection_node(const or_options_t* options, + const node_t* node) +{ + /* We'll connect directly all reachable addresses, whether preferred or not. + */ + return (rend_service_allow_non_anonymous_connection(options) && + fascist_firewall_allows_node(node, FIREWALL_OR_CONNECTION, 0)); +} + +/****** + * Handle cells + ******/ + +/** Respond to an INTRODUCE2 cell by launching a circuit to the chosen + * rendezvous point. + */ +int +rend_service_receive_introduction(origin_circuit_t *circuit, + const uint8_t *request, + size_t request_len) +{ + /* Global status stuff */ + int status = 0, result; + const or_options_t *options = get_options(); + char *err_msg = NULL; + int err_msg_severity = LOG_WARN; + const char *stage_descr = NULL, *rend_pk_digest; + int reason = END_CIRC_REASON_TORPROTOCOL; + /* Service/circuit/key stuff we can learn before parsing */ + char serviceid[REND_SERVICE_ID_LEN_BASE32+1]; + rend_service_t *service = NULL; + rend_intro_point_t *intro_point = NULL; + crypto_pk_t *intro_key = NULL; + /* Parsed cell */ + rend_intro_cell_t *parsed_req = NULL; + /* Rendezvous point */ + extend_info_t *rp = NULL; + /* XXX not handled yet */ + char buf[RELAY_PAYLOAD_SIZE]; + char keys[DIGEST_LEN+CPATH_KEY_MATERIAL_LEN]; /* Holds KH, Df, Db, Kf, Kb */ + int i; + crypto_dh_t *dh = NULL; + origin_circuit_t *launched = NULL; + crypt_path_t *cpath = NULL; + char hexcookie[9]; + int circ_needs_uptime; + time_t now = time(NULL); + time_t elapsed; + int replay; + ssize_t keylen; + + /* Do some initial validation and logging before we parse the cell */ + if (circuit->base_.purpose != CIRCUIT_PURPOSE_S_INTRO) { + log_warn(LD_PROTOCOL, + "Got an INTRODUCE2 over a non-introduction circuit %u.", + (unsigned) circuit->base_.n_circ_id); + goto err; + } + + assert_circ_anonymity_ok(circuit, options); + tor_assert(circuit->rend_data); + /* XXX: This is version 2 specific (only one supported). */ + rend_pk_digest = (char *) rend_data_get_pk_digest(circuit->rend_data, NULL); + + /* We'll use this in a bazillion log messages */ + base32_encode(serviceid, REND_SERVICE_ID_LEN_BASE32+1, + rend_pk_digest, REND_SERVICE_ID_LEN); + + /* look up service depending on circuit. */ + service = rend_service_get_by_pk_digest(rend_pk_digest); + if (!service) { + log_warn(LD_BUG, + "Internal error: Got an INTRODUCE2 cell on an intro " + "circ for an unrecognized service %s.", + escaped(serviceid)); + goto err; + } + + intro_point = find_intro_point(circuit); + if (intro_point == NULL) { + intro_point = find_expiring_intro_point(service, circuit); + if (intro_point == NULL) { + log_warn(LD_BUG, + "Internal error: Got an INTRODUCE2 cell on an " + "intro circ (for service %s) with no corresponding " + "rend_intro_point_t.", + escaped(serviceid)); + goto err; + } + } + + log_info(LD_REND, "Received INTRODUCE2 cell for service %s on circ %u.", + escaped(serviceid), (unsigned)circuit->base_.n_circ_id); + + /* use intro key instead of service key. */ + intro_key = circuit->intro_key; + + tor_free(err_msg); + stage_descr = NULL; + + stage_descr = "early parsing"; + /* Early parsing pass (get pk, ciphertext); type 2 is INTRODUCE2 */ + parsed_req = + rend_service_begin_parse_intro(request, request_len, 2, &err_msg); + if (!parsed_req) { + goto log_error; + } else if (err_msg) { + log_info(LD_REND, "%s on circ %u.", err_msg, + (unsigned)circuit->base_.n_circ_id); + tor_free(err_msg); + } + + /* make sure service replay caches are present */ + if (!service->accepted_intro_dh_parts) { + service->accepted_intro_dh_parts = + replaycache_new(REND_REPLAY_TIME_INTERVAL, + REND_REPLAY_TIME_INTERVAL); + } + + if (!intro_point->accepted_intro_rsa_parts) { + intro_point->accepted_intro_rsa_parts = replaycache_new(0, 0); + } + + /* check for replay of PK-encrypted portion. */ + keylen = crypto_pk_keysize(intro_key); + replay = replaycache_add_test_and_elapsed( + intro_point->accepted_intro_rsa_parts, + parsed_req->ciphertext, MIN(parsed_req->ciphertext_len, keylen), + &elapsed); + + if (replay) { + log_warn(LD_REND, + "Possible replay detected! We received an " + "INTRODUCE2 cell with same PK-encrypted part %d " + "seconds ago. Dropping cell.", + (int)elapsed); + goto err; + } + + stage_descr = "decryption"; + /* Now try to decrypt it */ + result = rend_service_decrypt_intro(parsed_req, intro_key, &err_msg); + if (result < 0) { + goto log_error; + } else if (err_msg) { + log_info(LD_REND, "%s on circ %u.", err_msg, + (unsigned)circuit->base_.n_circ_id); + tor_free(err_msg); + } + + stage_descr = "late parsing"; + /* Parse the plaintext */ + result = rend_service_parse_intro_plaintext(parsed_req, &err_msg); + if (result < 0) { + goto log_error; + } else if (err_msg) { + log_info(LD_REND, "%s on circ %u.", err_msg, + (unsigned)circuit->base_.n_circ_id); + tor_free(err_msg); + } + + stage_descr = "late validation"; + /* Validate the parsed plaintext parts */ + result = rend_service_validate_intro_late(parsed_req, &err_msg); + if (result < 0) { + goto log_error; + } else if (err_msg) { + log_info(LD_REND, "%s on circ %u.", err_msg, + (unsigned)circuit->base_.n_circ_id); + tor_free(err_msg); + } + stage_descr = NULL; + + /* Increment INTRODUCE2 counter */ + ++(intro_point->accepted_introduce2_count); + + /* Find the rendezvous point */ + rp = find_rp_for_intro(parsed_req, &err_msg); + if (!rp) { + err_msg_severity = LOG_PROTOCOL_WARN; + goto log_error; + } + + /* Check if we'd refuse to talk to this router */ + if (options->StrictNodes && + routerset_contains_extendinfo(options->ExcludeNodes, rp)) { + log_warn(LD_REND, "Client asked to rendezvous at a relay that we " + "exclude, and StrictNodes is set. Refusing service."); + reason = END_CIRC_REASON_INTERNAL; /* XXX might leak why we refused */ + goto err; + } + + base16_encode(hexcookie, 9, (const char *)(parsed_req->rc), 4); + + /* Check whether there is a past request with the same Diffie-Hellman, + * part 1. */ + replay = replaycache_add_test_and_elapsed( + service->accepted_intro_dh_parts, + parsed_req->dh, DH1024_KEY_LEN, + &elapsed); + + if (replay) { + /* A Tor client will send a new INTRODUCE1 cell with the same rend + * cookie and DH public key as its previous one if its intro circ + * times out while in state CIRCUIT_PURPOSE_C_INTRODUCE_ACK_WAIT . + * If we received the first INTRODUCE1 cell (the intro-point relay + * converts it into an INTRODUCE2 cell), we are already trying to + * connect to that rend point (and may have already succeeded); + * drop this cell. */ + log_info(LD_REND, "We received an " + "INTRODUCE2 cell with same first part of " + "Diffie-Hellman handshake %d seconds ago. Dropping " + "cell.", + (int) elapsed); + goto err; + } + + /* If the service performs client authorization, check included auth data. */ + if (service->clients) { + if (parsed_req->version == 3 && parsed_req->u.v3.auth_len > 0) { + if (rend_check_authorization(service, + (const char*)parsed_req->u.v3.auth_data, + parsed_req->u.v3.auth_len)) { + log_info(LD_REND, "Authorization data in INTRODUCE2 cell are valid."); + } else { + log_info(LD_REND, "The authorization data that are contained in " + "the INTRODUCE2 cell are invalid. Dropping cell."); + reason = END_CIRC_REASON_CONNECTFAILED; + goto err; + } + } else { + log_info(LD_REND, "INTRODUCE2 cell does not contain authentication " + "data, but we require client authorization. Dropping cell."); + reason = END_CIRC_REASON_CONNECTFAILED; + goto err; + } + } + + /* Try DH handshake... */ + dh = crypto_dh_new(DH_TYPE_REND); + if (!dh || crypto_dh_generate_public(dh)<0) { + log_warn(LD_BUG,"Internal error: couldn't build DH state " + "or generate public key."); + reason = END_CIRC_REASON_INTERNAL; + goto err; + } + if (crypto_dh_compute_secret(LOG_PROTOCOL_WARN, dh, + (char *)(parsed_req->dh), + DH1024_KEY_LEN, keys, + DIGEST_LEN+CPATH_KEY_MATERIAL_LEN)<0) { + log_warn(LD_BUG, "Internal error: couldn't complete DH handshake"); + reason = END_CIRC_REASON_INTERNAL; + goto err; + } + + circ_needs_uptime = hs_service_requires_uptime_circ(service->ports); + + /* help predict this next time */ + rep_hist_note_used_internal(now, circ_needs_uptime, 1); + + /* Launch a circuit to the client's chosen rendezvous point. + */ + int max_rend_failures=hs_get_service_max_rend_failures(); + for (i=0;i<max_rend_failures;i++) { + int flags = CIRCLAUNCH_NEED_CAPACITY | CIRCLAUNCH_IS_INTERNAL; + if (circ_needs_uptime) flags |= CIRCLAUNCH_NEED_UPTIME; + /* A Single Onion Service only uses a direct connection if its - * firewall rules permit direct connections to the address. */ - if (rend_service_use_direct_connection(options, rp)) { ++ * firewall rules permit direct connections to the address. ++ * ++ * We only use a one-hop path on the first attempt. If the first attempt ++ * fails, we use a 3-hop path for reachability / reliability. ++ * See the comment in rend_service_relauch_rendezvous() for details. */ ++ if (rend_service_use_direct_connection(options, rp) && i == 0) { + flags = flags | CIRCLAUNCH_ONEHOP_TUNNEL; + } + launched = circuit_launch_by_extend_info( + CIRCUIT_PURPOSE_S_CONNECT_REND, rp, flags); + + if (launched) + break; + } + if (!launched) { /* give up */ + log_warn(LD_REND, "Giving up launching first hop of circuit to rendezvous " + "point %s for service %s.", + safe_str_client(extend_info_describe(rp)), + serviceid); + reason = END_CIRC_REASON_CONNECTFAILED; + goto err; + } + log_info(LD_REND, + "Accepted intro; launching circuit to %s " + "(cookie %s) for service %s.", + safe_str_client(extend_info_describe(rp)), + hexcookie, serviceid); + tor_assert(launched->build_state); + /* Fill in the circuit's state. */ + + launched->rend_data = + rend_data_service_create(service->service_id, rend_pk_digest, + parsed_req->rc, service->auth_type); + + launched->build_state->service_pending_final_cpath_ref = + tor_malloc_zero(sizeof(crypt_path_reference_t)); + launched->build_state->service_pending_final_cpath_ref->refcount = 1; + + launched->build_state->service_pending_final_cpath_ref->cpath = cpath = + tor_malloc_zero(sizeof(crypt_path_t)); + cpath->magic = CRYPT_PATH_MAGIC; + launched->build_state->expiry_time = now + MAX_REND_TIMEOUT; + + cpath->rend_dh_handshake_state = dh; + dh = NULL; + if (circuit_init_cpath_crypto(cpath, + keys+DIGEST_LEN, sizeof(keys)-DIGEST_LEN, + 1, 0)<0) + goto err; + memcpy(cpath->rend_circ_nonce, keys, DIGEST_LEN); + + goto done; + + log_error: + if (!err_msg) { + if (stage_descr) { + tor_asprintf(&err_msg, + "unknown %s error for INTRODUCE2", stage_descr); + } else { + err_msg = tor_strdup("unknown error for INTRODUCE2"); + } + } + + log_fn(err_msg_severity, LD_REND, "%s on circ %u", err_msg, + (unsigned)circuit->base_.n_circ_id); + err: + status = -1; + if (dh) crypto_dh_free(dh); + if (launched) { + circuit_mark_for_close(TO_CIRCUIT(launched), reason); + } + tor_free(err_msg); + + done: + memwipe(keys, 0, sizeof(keys)); + memwipe(buf, 0, sizeof(buf)); + memwipe(serviceid, 0, sizeof(serviceid)); + memwipe(hexcookie, 0, sizeof(hexcookie)); + + /* Free the parsed cell */ + rend_service_free_intro(parsed_req); + + /* Free rp */ + extend_info_free(rp); + + return status; +} + +/** Given a parsed and decrypted INTRODUCE2, find the rendezvous point or + * return NULL and an error string if we can't. Return a newly allocated + * extend_info_t* for the rendezvous point. */ +static extend_info_t * +find_rp_for_intro(const rend_intro_cell_t *intro, + char **err_msg_out) +{ + extend_info_t *rp = NULL; + char *err_msg = NULL; + const char *rp_nickname = NULL; + const node_t *node = NULL; + + if (!intro) { + if (err_msg_out) + err_msg = tor_strdup("Bad parameters to find_rp_for_intro()"); + + goto err; + } + + if (intro->version == 0 || intro->version == 1) { + rp_nickname = (const char *)(intro->u.v0_v1.rp); + + node = node_get_by_nickname(rp_nickname, NNF_NO_WARN_UNNAMED); + if (!node) { + if (err_msg_out) { + tor_asprintf(&err_msg, + "Couldn't find router %s named in INTRODUCE2 cell", + escaped_safe_str_client(rp_nickname)); + } + + goto err; + } + + /* Are we in single onion mode? */ + const int allow_direct = rend_service_allow_non_anonymous_connection( + get_options()); + rp = extend_info_from_node(node, allow_direct); + if (!rp) { + if (err_msg_out) { + tor_asprintf(&err_msg, + "Couldn't build extend_info_t for router %s named " + "in INTRODUCE2 cell", + escaped_safe_str_client(rp_nickname)); + } + + goto err; + } + } else if (intro->version == 2) { + rp = extend_info_dup(intro->u.v2.extend_info); + } else if (intro->version == 3) { + rp = extend_info_dup(intro->u.v3.extend_info); + } else { + if (err_msg_out) { + tor_asprintf(&err_msg, + "Unknown version %d in INTRODUCE2 cell", + (int)(intro->version)); + } + + goto err; + } + + /* rp is always set here: extend_info_dup guarantees a non-NULL result, and + * the other cases goto err. */ + tor_assert(rp); + + /* Make sure the RP we are being asked to connect to is _not_ a private + * address unless it's allowed. Let's avoid to build a circuit to our + * second middle node and fail right after when extending to the RP. */ + if (!extend_info_addr_is_allowed(&rp->addr)) { + if (err_msg_out) { + tor_asprintf(&err_msg, + "Relay IP in INTRODUCE2 cell is private address."); + } + extend_info_free(rp); + rp = NULL; + goto err; + } + goto done; + + err: + if (err_msg_out) + *err_msg_out = err_msg; + else + tor_free(err_msg); + + done: + return rp; +} + +/** Free a parsed INTRODUCE1 or INTRODUCE2 cell that was allocated by + * rend_service_parse_intro(). + */ +void +rend_service_free_intro_(rend_intro_cell_t *request) +{ + if (!request) { + return; + } + + /* Free ciphertext */ + tor_free(request->ciphertext); + request->ciphertext_len = 0; + + /* Have plaintext? */ + if (request->plaintext) { + /* Zero it out just to be safe */ + memwipe(request->plaintext, 0, request->plaintext_len); + tor_free(request->plaintext); + request->plaintext_len = 0; + } + + /* Have parsed plaintext? */ + if (request->parsed) { + switch (request->version) { + case 0: + case 1: + /* + * Nothing more to do; these formats have no further pointers + * in them. + */ + break; + case 2: + extend_info_free(request->u.v2.extend_info); + request->u.v2.extend_info = NULL; + break; + case 3: + if (request->u.v3.auth_data) { + memwipe(request->u.v3.auth_data, 0, request->u.v3.auth_len); + tor_free(request->u.v3.auth_data); + } + + extend_info_free(request->u.v3.extend_info); + request->u.v3.extend_info = NULL; + break; + default: + log_info(LD_BUG, + "rend_service_free_intro() saw unknown protocol " + "version %d.", + request->version); + } + } + + /* Zero it out to make sure sensitive stuff doesn't hang around in memory */ + memwipe(request, 0, sizeof(*request)); + + tor_free(request); +} + +/** Parse an INTRODUCE1 or INTRODUCE2 cell into a newly allocated + * rend_intro_cell_t structure. Free it with rend_service_free_intro() + * when finished. The type parameter should be 1 or 2 to indicate whether + * this is INTRODUCE1 or INTRODUCE2. This parses only the non-encrypted + * parts; after this, call rend_service_decrypt_intro() with a key, then + * rend_service_parse_intro_plaintext() to finish parsing. The optional + * err_msg_out parameter is set to a string suitable for log output + * if parsing fails. This function does some validation, but only + * that which depends solely on the contents of the cell and the + * key; it can be unit-tested. Further validation is done in + * rend_service_validate_intro(). + */ + +rend_intro_cell_t * +rend_service_begin_parse_intro(const uint8_t *request, + size_t request_len, + uint8_t type, + char **err_msg_out) +{ + rend_intro_cell_t *rv = NULL; + char *err_msg = NULL; + + if (!request || request_len <= 0) goto err; + if (!(type == 1 || type == 2)) goto err; + + /* First, check that the cell is long enough to be a sensible INTRODUCE */ + + /* min key length plus digest length plus nickname length */ + if (request_len < + (DIGEST_LEN + REND_COOKIE_LEN + (MAX_NICKNAME_LEN + 1) + + DH1024_KEY_LEN + 42)) { + if (err_msg_out) { + tor_asprintf(&err_msg, + "got a truncated INTRODUCE%d cell", + (int)type); + } + goto err; + } + + /* Allocate a new parsed cell structure */ + rv = tor_malloc_zero(sizeof(*rv)); + + /* Set the type */ + rv->type = type; + + /* Copy in the ID */ + memcpy(rv->pk, request, DIGEST_LEN); + + /* Copy in the ciphertext */ + rv->ciphertext = tor_malloc(request_len - DIGEST_LEN); + memcpy(rv->ciphertext, request + DIGEST_LEN, request_len - DIGEST_LEN); + rv->ciphertext_len = request_len - DIGEST_LEN; + + goto done; + + err: + rend_service_free_intro(rv); + rv = NULL; + + if (err_msg_out && !err_msg) { + tor_asprintf(&err_msg, + "unknown INTRODUCE%d error", + (int)type); + } + + done: + if (err_msg_out) *err_msg_out = err_msg; + else tor_free(err_msg); + + return rv; +} + +/** Parse the version-specific parts of a v0 or v1 INTRODUCE1 or INTRODUCE2 + * cell + */ + +static ssize_t +rend_service_parse_intro_for_v0_or_v1( + rend_intro_cell_t *intro, + const uint8_t *buf, + size_t plaintext_len, + char **err_msg_out) +{ + const char *rp_nickname, *endptr; + size_t nickname_field_len, ver_specific_len; + + if (intro->version == 1) { + ver_specific_len = MAX_HEX_NICKNAME_LEN + 2; + rp_nickname = ((const char *)buf) + 1; + nickname_field_len = MAX_HEX_NICKNAME_LEN + 1; + } else if (intro->version == 0) { + ver_specific_len = MAX_NICKNAME_LEN + 1; + rp_nickname = (const char *)buf; + nickname_field_len = MAX_NICKNAME_LEN + 1; + } else { + if (err_msg_out) + tor_asprintf(err_msg_out, + "rend_service_parse_intro_for_v0_or_v1() called with " + "bad version %d on INTRODUCE%d cell (this is a bug)", + intro->version, + (int)(intro->type)); + goto err; + } + + if (plaintext_len < ver_specific_len) { + if (err_msg_out) + tor_asprintf(err_msg_out, + "short plaintext of encrypted part in v1 INTRODUCE%d " + "cell (%lu bytes, needed %lu)", + (int)(intro->type), + (unsigned long)plaintext_len, + (unsigned long)ver_specific_len); + goto err; + } + + endptr = memchr(rp_nickname, 0, nickname_field_len); + if (!endptr || endptr == rp_nickname) { + if (err_msg_out) { + tor_asprintf(err_msg_out, + "couldn't find a nul-padded nickname in " + "INTRODUCE%d cell", + (int)(intro->type)); + } + goto err; + } + + if ((intro->version == 0 && + !is_legal_nickname(rp_nickname)) || + (intro->version == 1 && + !is_legal_nickname_or_hexdigest(rp_nickname))) { + if (err_msg_out) { + tor_asprintf(err_msg_out, + "bad nickname in INTRODUCE%d cell", + (int)(intro->type)); + } + goto err; + } + + memcpy(intro->u.v0_v1.rp, rp_nickname, endptr - rp_nickname + 1); + + return ver_specific_len; + + err: + return -1; +} + +/** Parse the version-specific parts of a v2 INTRODUCE1 or INTRODUCE2 cell + */ + +static ssize_t +rend_service_parse_intro_for_v2( + rend_intro_cell_t *intro, + const uint8_t *buf, + size_t plaintext_len, + char **err_msg_out) +{ + unsigned int klen; + extend_info_t *extend_info = NULL; + ssize_t ver_specific_len; + + /* + * We accept version 3 too so that the v3 parser can call this with + * an adjusted buffer for the latter part of a v3 cell, which is + * identical to a v2 cell. + */ + if (!(intro->version == 2 || + intro->version == 3)) { + if (err_msg_out) + tor_asprintf(err_msg_out, + "rend_service_parse_intro_for_v2() called with " + "bad version %d on INTRODUCE%d cell (this is a bug)", + intro->version, + (int)(intro->type)); + goto err; + } + + /* 7 == version, IP and port, DIGEST_LEN == id, 2 == key length */ + if (plaintext_len < 7 + DIGEST_LEN + 2) { + if (err_msg_out) { + tor_asprintf(err_msg_out, + "truncated plaintext of encrypted parted of " + "version %d INTRODUCE%d cell", + intro->version, + (int)(intro->type)); + } + + goto err; + } + + extend_info = tor_malloc_zero(sizeof(extend_info_t)); + tor_addr_from_ipv4n(&extend_info->addr, get_uint32(buf + 1)); + extend_info->port = ntohs(get_uint16(buf + 5)); + memcpy(extend_info->identity_digest, buf + 7, DIGEST_LEN); + extend_info->nickname[0] = '$'; + base16_encode(extend_info->nickname + 1, sizeof(extend_info->nickname) - 1, + extend_info->identity_digest, DIGEST_LEN); + klen = ntohs(get_uint16(buf + 7 + DIGEST_LEN)); + + /* 7 == version, IP and port, DIGEST_LEN == id, 2 == key length */ + if (plaintext_len < 7 + DIGEST_LEN + 2 + klen) { + if (err_msg_out) { + tor_asprintf(err_msg_out, + "truncated plaintext of encrypted parted of " + "version %d INTRODUCE%d cell", + intro->version, + (int)(intro->type)); + } + + goto err; + } + + extend_info->onion_key = + crypto_pk_asn1_decode((const char *)(buf + 7 + DIGEST_LEN + 2), klen); + if (!extend_info->onion_key) { + if (err_msg_out) { + tor_asprintf(err_msg_out, + "error decoding onion key in version %d " + "INTRODUCE%d cell", + intro->version, + (intro->type)); + } + + goto err; + } + if (128 != crypto_pk_keysize(extend_info->onion_key)) { + if (err_msg_out) { + tor_asprintf(err_msg_out, + "invalid onion key size in version %d INTRODUCE%d cell", + intro->version, + (intro->type)); + } + + goto err; + } + + ver_specific_len = 7+DIGEST_LEN+2+klen; + + if (intro->version == 2) intro->u.v2.extend_info = extend_info; + else intro->u.v3.extend_info = extend_info; + + return ver_specific_len; + + err: + extend_info_free(extend_info); + + return -1; +} + +/** Parse the version-specific parts of a v3 INTRODUCE1 or INTRODUCE2 cell + */ + +static ssize_t +rend_service_parse_intro_for_v3( + rend_intro_cell_t *intro, + const uint8_t *buf, + size_t plaintext_len, + char **err_msg_out) +{ + ssize_t adjust, v2_ver_specific_len, ts_offset; + + /* This should only be called on v3 cells */ + if (intro->version != 3) { + if (err_msg_out) + tor_asprintf(err_msg_out, + "rend_service_parse_intro_for_v3() called with " + "bad version %d on INTRODUCE%d cell (this is a bug)", + intro->version, + (int)(intro->type)); + goto err; + } + + /* + * Check that we have at least enough to get auth_len: + * + * 1 octet for version, 1 for auth_type, 2 for auth_len + */ + if (plaintext_len < 4) { + if (err_msg_out) { + tor_asprintf(err_msg_out, + "truncated plaintext of encrypted parted of " + "version %d INTRODUCE%d cell", + intro->version, + (int)(intro->type)); + } + + goto err; + } + + /* + * The rend_client_send_introduction() function over in rendclient.c is + * broken (i.e., fails to match the spec) in such a way that we can't + * change it without breaking the protocol. Specifically, it doesn't + * emit auth_len when auth-type is REND_NO_AUTH, so everything is off + * by two bytes after that. Calculate ts_offset and do everything from + * the timestamp on relative to that to handle this dain bramage. + */ + + intro->u.v3.auth_type = buf[1]; + if (intro->u.v3.auth_type != REND_NO_AUTH) { + intro->u.v3.auth_len = ntohs(get_uint16(buf + 2)); + ts_offset = 4 + intro->u.v3.auth_len; + } else { + intro->u.v3.auth_len = 0; + ts_offset = 2; + } + + /* Check that auth len makes sense for this auth type */ + if (intro->u.v3.auth_type == REND_BASIC_AUTH || + intro->u.v3.auth_type == REND_STEALTH_AUTH) { + if (intro->u.v3.auth_len != REND_DESC_COOKIE_LEN) { + if (err_msg_out) { + tor_asprintf(err_msg_out, + "wrong auth data size %d for INTRODUCE%d cell, " + "should be %d", + (int)(intro->u.v3.auth_len), + (int)(intro->type), + REND_DESC_COOKIE_LEN); + } + + goto err; + } + } + + /* Check that we actually have everything up through the timestamp */ + if (plaintext_len < (size_t)(ts_offset)+4) { + if (err_msg_out) { + tor_asprintf(err_msg_out, + "truncated plaintext of encrypted parted of " + "version %d INTRODUCE%d cell", + intro->version, + (int)(intro->type)); + } + + goto err; + } + + if (intro->u.v3.auth_type != REND_NO_AUTH && + intro->u.v3.auth_len > 0) { + /* Okay, we can go ahead and copy auth_data */ + intro->u.v3.auth_data = tor_malloc(intro->u.v3.auth_len); + /* + * We know we had an auth_len field in this case, so 4 is + * always right. + */ + memcpy(intro->u.v3.auth_data, buf + 4, intro->u.v3.auth_len); + } + + /* + * From here on, the format is as in v2, so we call the v2 parser with + * adjusted buffer and length. We are 4 + ts_offset octets in, but the + * v2 parser expects to skip over a version byte at the start, so we + * adjust by 3 + ts_offset. + */ + adjust = 3 + ts_offset; + + v2_ver_specific_len = + rend_service_parse_intro_for_v2(intro, + buf + adjust, plaintext_len - adjust, + err_msg_out); + + /* Success in v2 parser */ + if (v2_ver_specific_len >= 0) return v2_ver_specific_len + adjust; + /* Failure in v2 parser; it will have provided an err_msg */ + else return v2_ver_specific_len; + + err: + return -1; +} + +/** Table of parser functions for version-specific parts of an INTRODUCE2 + * cell. + */ + +static ssize_t + (*intro_version_handlers[])( + rend_intro_cell_t *, + const uint8_t *, + size_t, + char **) = +{ rend_service_parse_intro_for_v0_or_v1, + rend_service_parse_intro_for_v0_or_v1, + rend_service_parse_intro_for_v2, + rend_service_parse_intro_for_v3 }; + +/** Decrypt the encrypted part of an INTRODUCE1 or INTRODUCE2 cell, + * return 0 if successful, or < 0 and write an error message to + * *err_msg_out if provided. + */ + +int +rend_service_decrypt_intro( + rend_intro_cell_t *intro, + crypto_pk_t *key, + char **err_msg_out) +{ + char *err_msg = NULL; + uint8_t key_digest[DIGEST_LEN]; + char service_id[REND_SERVICE_ID_LEN_BASE32+1]; + ssize_t key_len; + uint8_t buf[RELAY_PAYLOAD_SIZE]; + int result, status = -1; + + if (!intro || !key) { + if (err_msg_out) { + err_msg = + tor_strdup("rend_service_decrypt_intro() called with bad " + "parameters"); + } + + status = -2; + goto err; + } + + /* Make sure we have ciphertext */ + if (!(intro->ciphertext) || intro->ciphertext_len <= 0) { + if (err_msg_out) { + tor_asprintf(&err_msg, + "rend_intro_cell_t was missing ciphertext for " + "INTRODUCE%d cell", + (int)(intro->type)); + } + status = -3; + goto err; + } + + /* Check that this cell actually matches this service key */ + + /* first DIGEST_LEN bytes of request is intro or service pk digest */ + if (crypto_pk_get_digest(key, (char *)key_digest) < 0) { + if (err_msg_out) + *err_msg_out = tor_strdup("Couldn't compute RSA digest."); + log_warn(LD_BUG, "Couldn't compute key digest."); + status = -7; + goto err; + } + + if (tor_memneq(key_digest, intro->pk, DIGEST_LEN)) { + if (err_msg_out) { + base32_encode(service_id, REND_SERVICE_ID_LEN_BASE32 + 1, + (char*)(intro->pk), REND_SERVICE_ID_LEN); + tor_asprintf(&err_msg, + "got an INTRODUCE%d cell for the wrong service (%s)", + (int)(intro->type), + escaped(service_id)); + } + + status = -4; + goto err; + } + + /* Make sure the encrypted part is long enough to decrypt */ + + key_len = crypto_pk_keysize(key); + if (intro->ciphertext_len < key_len) { + if (err_msg_out) { + tor_asprintf(&err_msg, + "got an INTRODUCE%d cell with a truncated PK-encrypted " + "part", + (int)(intro->type)); + } + + status = -5; + goto err; + } + + /* Decrypt the encrypted part */ + result = + crypto_pk_obsolete_private_hybrid_decrypt( + key, (char *)buf, sizeof(buf), + (const char *)(intro->ciphertext), intro->ciphertext_len, + PK_PKCS1_OAEP_PADDING, 1); + if (result < 0) { + if (err_msg_out) { + tor_asprintf(&err_msg, + "couldn't decrypt INTRODUCE%d cell", + (int)(intro->type)); + } + status = -6; + goto err; + } + intro->plaintext_len = result; + intro->plaintext = tor_malloc(intro->plaintext_len); + memcpy(intro->plaintext, buf, intro->plaintext_len); + + status = 0; + + goto done; + + err: + if (err_msg_out && !err_msg) { + tor_asprintf(&err_msg, + "unknown INTRODUCE%d error decrypting encrypted part", + intro ? (int)(intro->type) : -1); + } + + done: + if (err_msg_out) *err_msg_out = err_msg; + else tor_free(err_msg); + + /* clean up potentially sensitive material */ + memwipe(buf, 0, sizeof(buf)); + memwipe(key_digest, 0, sizeof(key_digest)); + memwipe(service_id, 0, sizeof(service_id)); + + return status; +} + +/** Parse the plaintext of the encrypted part of an INTRODUCE1 or + * INTRODUCE2 cell, return 0 if successful, or < 0 and write an error + * message to *err_msg_out if provided. + */ + +int +rend_service_parse_intro_plaintext( + rend_intro_cell_t *intro, + char **err_msg_out) +{ + char *err_msg = NULL; + ssize_t ver_specific_len, ver_invariant_len; + uint8_t version; + int status = -1; + + if (!intro) { + if (err_msg_out) { + err_msg = + tor_strdup("rend_service_parse_intro_plaintext() called with NULL " + "rend_intro_cell_t"); + } + + status = -2; + goto err; + } + + /* Check that we have plaintext */ + if (!(intro->plaintext) || intro->plaintext_len <= 0) { + if (err_msg_out) { + err_msg = tor_strdup("rend_intro_cell_t was missing plaintext"); + } + status = -3; + goto err; + } + + /* In all formats except v0, the first byte is a version number */ + version = intro->plaintext[0]; + + /* v0 has no version byte (stupid...), so handle it as a fallback */ + if (version > 3) version = 0; + + /* Copy the version into the parsed cell structure */ + intro->version = version; + + /* Call the version-specific parser from the table */ + ver_specific_len = + intro_version_handlers[version](intro, + intro->plaintext, intro->plaintext_len, + &err_msg); + if (ver_specific_len < 0) { + status = -4; + goto err; + } + + /** The rendezvous cookie and Diffie-Hellman stuff are version-invariant + * and at the end of the plaintext of the encrypted part of the cell. + */ + + ver_invariant_len = intro->plaintext_len - ver_specific_len; + if (ver_invariant_len < REND_COOKIE_LEN + DH1024_KEY_LEN) { + tor_asprintf(&err_msg, + "decrypted plaintext of INTRODUCE%d cell was truncated (%ld bytes)", + (int)(intro->type), + (long)(intro->plaintext_len)); + status = -5; + goto err; + } else if (ver_invariant_len > REND_COOKIE_LEN + DH1024_KEY_LEN) { + tor_asprintf(&err_msg, + "decrypted plaintext of INTRODUCE%d cell was too long (%ld bytes)", + (int)(intro->type), + (long)(intro->plaintext_len)); + status = -6; + goto err; + } else { + memcpy(intro->rc, + intro->plaintext + ver_specific_len, + REND_COOKIE_LEN); + memcpy(intro->dh, + intro->plaintext + ver_specific_len + REND_COOKIE_LEN, + DH1024_KEY_LEN); + } + + /* Flag it as being fully parsed */ + intro->parsed = 1; + + status = 0; + goto done; + + err: + if (err_msg_out && !err_msg) { + tor_asprintf(&err_msg, + "unknown INTRODUCE%d error parsing encrypted part", + intro ? (int)(intro->type) : -1); + } + + done: + if (err_msg_out) *err_msg_out = err_msg; + else tor_free(err_msg); + + return status; +} + +/** Do validity checks on a parsed intro cell after decryption; some of + * these are not done in rend_service_parse_intro_plaintext() itself because + * they depend on a lot of other state and would make it hard to unit test. + * Returns >= 0 if successful or < 0 if the intro cell is invalid, and + * optionally writes out an error message for logging. If an err_msg + * pointer is provided, it is the caller's responsibility to free any + * provided message. + */ + +int +rend_service_validate_intro_late(const rend_intro_cell_t *intro, + char **err_msg_out) +{ + int status = 0; + + if (!intro) { + if (err_msg_out) + *err_msg_out = + tor_strdup("NULL intro cell passed to " + "rend_service_validate_intro_late()"); + + status = -1; + goto err; + } + + if (intro->version == 3 && intro->parsed) { + if (!(intro->u.v3.auth_type == REND_NO_AUTH || + intro->u.v3.auth_type == REND_BASIC_AUTH || + intro->u.v3.auth_type == REND_STEALTH_AUTH)) { + /* This is an informative message, not an error, as in the old code */ + if (err_msg_out) + tor_asprintf(err_msg_out, + "unknown authorization type %d", + intro->u.v3.auth_type); + } + } + + err: + return status; +} + +/** 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. + */ +void +rend_service_relaunch_rendezvous(origin_circuit_t *oldcirc) +{ + origin_circuit_t *newcirc; + cpath_build_state_t *newstate, *oldstate; + + tor_assert(oldcirc->base_.purpose == CIRCUIT_PURPOSE_S_CONNECT_REND); + oldstate = oldcirc->build_state; + tor_assert(oldstate); + + if (oldstate->service_pending_final_cpath_ref == NULL) { + log_info(LD_REND,"Skipping relaunch of circ that failed on its first hop. " + "Initiator will retry."); + return; + } + + log_info(LD_REND,"Reattempting rendezvous circuit to '%s'", + safe_str(extend_info_describe(oldstate->chosen_exit))); + + /* You'd think Single Onion Services would want to retry the rendezvous + * using a direct connection. But if it's blocked by a firewall, or the + * service is IPv6-only, or the rend point avoiding becoming a one-hop + * proxy, we need a 3-hop connection. */ + newcirc = circuit_launch_by_extend_info(CIRCUIT_PURPOSE_S_CONNECT_REND, + oldstate->chosen_exit, + CIRCLAUNCH_NEED_CAPACITY|CIRCLAUNCH_IS_INTERNAL); + + if (!newcirc) { + log_warn(LD_REND,"Couldn't relaunch rendezvous circuit to '%s'.", + safe_str(extend_info_describe(oldstate->chosen_exit))); + return; + } + newstate = newcirc->build_state; + tor_assert(newstate); + newstate->failure_count = oldstate->failure_count+1; + newstate->expiry_time = oldstate->expiry_time; + newstate->service_pending_final_cpath_ref = + oldstate->service_pending_final_cpath_ref; + ++(newstate->service_pending_final_cpath_ref->refcount); + + newcirc->rend_data = rend_data_dup(oldcirc->rend_data); +} + +/** Launch a circuit to serve as an introduction point for the service + * service at the introduction point nickname + */ +static int +rend_service_launch_establish_intro(rend_service_t *service, + rend_intro_point_t *intro) +{ + origin_circuit_t *launched; + int flags = CIRCLAUNCH_NEED_UPTIME|CIRCLAUNCH_IS_INTERNAL; + const or_options_t *options = get_options(); + extend_info_t *launch_ei = intro->extend_info; + extend_info_t *direct_ei = NULL; + - /* Are we in single onion mode? */ - if (rend_service_allow_non_anonymous_connection(options)) { ++ /* Are we in single onion mode? ++ * ++ * We only use a one-hop path on the first attempt. If the first attempt ++ * fails, we use a 3-hop path for reachability / reliability. ++ * (Unlike v3, retries is incremented by the caller after it calls this ++ * function.) ++ */ ++ if (rend_service_allow_non_anonymous_connection(options) && ++ intro->circuit_retries == 0) { + /* Do we have a descriptor for the node? + * We've either just chosen it from the consensus, or we've just reviewed + * our intro points to see which ones are still valid, and deleted the ones + * that aren't in the consensus any more. */ + const node_t *node = node_get_by_id(launch_ei->identity_digest); + if (BUG(!node)) { + /* The service has kept an intro point after it went missing from the + * consensus. If we did anything else here, it would be a consensus + * distinguisher. Which are less of an issue for single onion services, + * but still a bug. */ + return -1; + } + /* Can we connect to the node directly? If so, replace launch_ei + * (a multi-hop extend_info) with one suitable for direct connection. */ + if (rend_service_use_direct_connection_node(options, node)) { + direct_ei = extend_info_from_node(node, 1); + if (BUG(!direct_ei)) { + /* rend_service_use_direct_connection_node and extend_info_from_node + * disagree about which addresses on this node are permitted. This + * should never happen. Avoiding the connection is a safe response. */ + return -1; + } + flags = flags | CIRCLAUNCH_ONEHOP_TUNNEL; + launch_ei = direct_ei; + } + } + /* launch_ei is either intro->extend_info, or has been replaced with a valid + * extend_info for single onion service direct connection. */ + tor_assert(launch_ei); + /* We must have the same intro when making a direct connection. */ + tor_assert(tor_memeq(intro->extend_info->identity_digest, + launch_ei->identity_digest, + DIGEST_LEN)); + + log_info(LD_REND, + "Launching circuit to introduction point %s%s%s for service %s", + safe_str_client(extend_info_describe(intro->extend_info)), + direct_ei ? " via direct address " : "", + direct_ei ? safe_str_client(extend_info_describe(direct_ei)) : "", + service->service_id); + + rep_hist_note_used_internal(time(NULL), 1, 0); + + ++service->n_intro_circuits_launched; + launched = circuit_launch_by_extend_info(CIRCUIT_PURPOSE_S_ESTABLISH_INTRO, + launch_ei, flags); + + if (!launched) { + log_info(LD_REND, + "Can't launch circuit to establish introduction at %s%s%s.", + safe_str_client(extend_info_describe(intro->extend_info)), + direct_ei ? " via direct address " : "", + direct_ei ? safe_str_client(extend_info_describe(direct_ei)) : "" + ); + extend_info_free(direct_ei); + return -1; + } + /* We must have the same exit node even if cannibalized or direct connection. + */ + tor_assert(tor_memeq(intro->extend_info->identity_digest, + launched->build_state->chosen_exit->identity_digest, + DIGEST_LEN)); + + launched->rend_data = rend_data_service_create(service->service_id, + service->pk_digest, NULL, + service->auth_type); + launched->intro_key = crypto_pk_dup_key(intro->intro_key); + if (launched->base_.state == CIRCUIT_STATE_OPEN) + rend_service_intro_has_opened(launched); + extend_info_free(direct_ei); + return 0; +} + +/** Return the number of introduction points that are established for the + * given service. */ +static unsigned int +count_established_intro_points(const rend_service_t *service) +{ + unsigned int num = 0; + + SMARTLIST_FOREACH(service->intro_nodes, rend_intro_point_t *, intro, + num += intro->circuit_established + ); + return num; +} + +/** Return the number of introduction points that are or are being + * established for the given service. This function iterates over all + * circuit and count those that are linked to the service and are waiting + * for the intro point to respond. */ +static unsigned int +count_intro_point_circuits(const rend_service_t *service) +{ + unsigned int num_ipos = 0; + SMARTLIST_FOREACH_BEGIN(circuit_get_global_list(), circuit_t *, circ) { + if (!circ->marked_for_close && + circ->state == CIRCUIT_STATE_OPEN && + (circ->purpose == CIRCUIT_PURPOSE_S_ESTABLISH_INTRO || + circ->purpose == CIRCUIT_PURPOSE_S_INTRO)) { + origin_circuit_t *oc = TO_ORIGIN_CIRCUIT(circ); + if (oc->rend_data && + rend_circuit_pk_digest_eq(oc, (uint8_t *) service->pk_digest)) { + num_ipos++; + } + } + } + SMARTLIST_FOREACH_END(circ); + return num_ipos; +} + +/* Given a buffer of at least RELAY_PAYLOAD_SIZE bytes in cell_body_out, + write the body of a legacy ESTABLISH_INTRO cell in it. Use intro_key + as the intro point auth key, and rend_circ_nonce as the circuit + crypto material. On success, fill cell_body_out and return the number + of bytes written. On fail, return -1. + */ +ssize_t +rend_service_encode_establish_intro_cell(char *cell_body_out, + size_t cell_body_out_len, + crypto_pk_t *intro_key, + const char *rend_circ_nonce) +{ + int retval = -1; + int r; + int len = 0; + char auth[DIGEST_LEN + 9]; + + tor_assert(intro_key); + tor_assert(rend_circ_nonce); + + /* Build the payload for a RELAY_ESTABLISH_INTRO cell. */ + r = crypto_pk_asn1_encode(intro_key, cell_body_out+2, + RELAY_PAYLOAD_SIZE-2); + if (r < 0) { + log_warn(LD_BUG, "Internal error; failed to establish intro point."); + goto err; + } + len = r; + set_uint16(cell_body_out, htons((uint16_t)len)); + len += 2; + memcpy(auth, rend_circ_nonce, DIGEST_LEN); + memcpy(auth+DIGEST_LEN, "INTRODUCE", 9); + if (crypto_digest(cell_body_out+len, auth, DIGEST_LEN+9)) + goto err; + len += 20; + r = crypto_pk_private_sign_digest(intro_key, cell_body_out+len, + cell_body_out_len - len, + cell_body_out, len); + if (r<0) { + log_warn(LD_BUG, "Internal error: couldn't sign introduction request."); + goto err; + } + len += r; + + retval = len; + + err: + memwipe(auth, 0, sizeof(auth)); + + return retval; +} + +/** Called when we're done building a circuit to an introduction point: + * sends a RELAY_ESTABLISH_INTRO cell. + */ +void +rend_service_intro_has_opened(origin_circuit_t *circuit) +{ + rend_service_t *service; + char buf[RELAY_PAYLOAD_SIZE]; + char serviceid[REND_SERVICE_ID_LEN_BASE32+1]; + unsigned int expiring_nodes_len, num_ip_circuits, valid_ip_circuits = 0; + int reason = END_CIRC_REASON_TORPROTOCOL; + const char *rend_pk_digest; + + tor_assert(circuit->base_.purpose == CIRCUIT_PURPOSE_S_ESTABLISH_INTRO); + assert_circ_anonymity_ok(circuit, get_options()); + tor_assert(circuit->cpath); + tor_assert(circuit->rend_data); + /* XXX: This is version 2 specific (only on supported). */ + rend_pk_digest = (char *) rend_data_get_pk_digest(circuit->rend_data, NULL); + + base32_encode(serviceid, REND_SERVICE_ID_LEN_BASE32+1, + rend_pk_digest, REND_SERVICE_ID_LEN); + + service = rend_service_get_by_pk_digest(rend_pk_digest); + if (!service) { + log_warn(LD_REND, "Unrecognized service ID %s on introduction circuit %u.", + safe_str_client(serviceid), (unsigned)circuit->base_.n_circ_id); + reason = END_CIRC_REASON_NOSUCHSERVICE; + goto err; + } + + /* Take the current amount of expiring nodes and the current amount of IP + * circuits and compute how many valid IP circuits we have. */ + expiring_nodes_len = (unsigned int) smartlist_len(service->expiring_nodes); + num_ip_circuits = count_intro_point_circuits(service); + /* Let's avoid an underflow. The valid_ip_circuits is initialized to 0 in + * case this condition turns out false because it means that all circuits + * are expiring so we need to keep this circuit. */ + if (num_ip_circuits > expiring_nodes_len) { + valid_ip_circuits = num_ip_circuits - expiring_nodes_len; + } + + /* If we already have enough introduction circuits for this service, + * redefine this one as a general circuit or close it, depending. + * Subtract the amount of expiring nodes here because the circuits are + * still opened. */ + if (valid_ip_circuits > service->n_intro_points_wanted) { + const or_options_t *options = get_options(); + /* Remove the intro point associated with this circuit, it's being + * repurposed or closed thus cleanup memory. */ + rend_intro_point_t *intro = find_intro_point(circuit); + if (intro != NULL) { + smartlist_remove(service->intro_nodes, intro); + rend_intro_point_free(intro); + } + + if (options->ExcludeNodes) { + /* XXXX in some future version, we can test whether the transition is + allowed or not given the actual nodes in the circuit. But for now, + this case, we might as well close the thing. */ + log_info(LD_CIRC|LD_REND, "We have just finished an introduction " + "circuit, but we already have enough. Closing it."); + reason = END_CIRC_REASON_NONE; + goto err; + } else { + tor_assert(circuit->build_state->is_internal); + log_info(LD_CIRC|LD_REND, "We have just finished an introduction " + "circuit, but we already have enough. Redefining purpose to " + "general; leaving as internal."); + + if (circuit_should_use_vanguards(TO_CIRCUIT(circuit)->purpose)) { + circuit_change_purpose(TO_CIRCUIT(circuit), + CIRCUIT_PURPOSE_HS_VANGUARDS); + } else { + circuit_change_purpose(TO_CIRCUIT(circuit), CIRCUIT_PURPOSE_C_GENERAL); + } + + { + rend_data_free(circuit->rend_data); + circuit->rend_data = NULL; + } + { + crypto_pk_t *intro_key = circuit->intro_key; + circuit->intro_key = NULL; + crypto_pk_free(intro_key); + } + + circuit_has_opened(circuit); + goto done; + } + } + + log_info(LD_REND, + "Established circuit %u as introduction point for service %s", + (unsigned)circuit->base_.n_circ_id, serviceid); + circuit_log_path(LOG_INFO, LD_REND, circuit); + + /* Send the ESTABLISH_INTRO cell */ + { + ssize_t len; + len = rend_service_encode_establish_intro_cell(buf, sizeof(buf), + circuit->intro_key, + circuit->cpath->prev->rend_circ_nonce); + if (len < 0) { + reason = END_CIRC_REASON_INTERNAL; + goto err; + } + + if (relay_send_command_from_edge(0, TO_CIRCUIT(circuit), + RELAY_COMMAND_ESTABLISH_INTRO, + buf, len, circuit->cpath->prev)<0) { + log_info(LD_GENERAL, + "Couldn't send introduction request for service %s on circuit %u", + serviceid, (unsigned)circuit->base_.n_circ_id); + goto done; + } + } + + /* We've attempted to use this circuit */ + pathbias_count_use_attempt(circuit); + + goto done; + + err: + circuit_mark_for_close(TO_CIRCUIT(circuit), reason); + done: + memwipe(buf, 0, sizeof(buf)); + memwipe(serviceid, 0, sizeof(serviceid)); + + return; +} + +/** Called when we get an INTRO_ESTABLISHED cell; mark the circuit as a + * live introduction point, and note that the service descriptor is + * now out-of-date. */ +int +rend_service_intro_established(origin_circuit_t *circuit, + const uint8_t *request, + size_t request_len) +{ + rend_service_t *service; + rend_intro_point_t *intro; + char serviceid[REND_SERVICE_ID_LEN_BASE32+1]; + (void) request; + (void) request_len; + tor_assert(circuit->rend_data); + /* XXX: This is version 2 specific (only supported one for now). */ + const char *rend_pk_digest = + (char *) rend_data_get_pk_digest(circuit->rend_data, NULL); + + if (circuit->base_.purpose != CIRCUIT_PURPOSE_S_ESTABLISH_INTRO) { + log_warn(LD_PROTOCOL, + "received INTRO_ESTABLISHED cell on non-intro circuit."); + goto err; + } + service = rend_service_get_by_pk_digest(rend_pk_digest); + if (!service) { + log_warn(LD_REND, "Unknown service on introduction circuit %u.", + (unsigned)circuit->base_.n_circ_id); + goto err; + } + base32_encode(serviceid, REND_SERVICE_ID_LEN_BASE32 + 1, + rend_pk_digest, REND_SERVICE_ID_LEN); + /* We've just successfully established a intro circuit to one of our + * introduction point, account for it. */ + intro = find_intro_point(circuit); + if (intro == NULL) { + log_warn(LD_REND, + "Introduction circuit established without a rend_intro_point_t " + "object for service %s on circuit %u", + safe_str_client(serviceid), (unsigned)circuit->base_.n_circ_id); + goto err; + } + intro->circuit_established = 1; + /* We might not have every introduction point ready but at this point we + * know that the descriptor needs to be uploaded. */ + service->desc_is_dirty = time(NULL); + circuit_change_purpose(TO_CIRCUIT(circuit), CIRCUIT_PURPOSE_S_INTRO); + + log_info(LD_REND, + "Received INTRO_ESTABLISHED cell on circuit %u for service %s", + (unsigned)circuit->base_.n_circ_id, serviceid); + + /* Getting a valid INTRODUCE_ESTABLISHED means we've successfully + * used the circ */ + pathbias_mark_use_success(circuit); + + return 0; + err: + circuit_mark_for_close(TO_CIRCUIT(circuit), END_CIRC_REASON_TORPROTOCOL); + return -1; +} + +/** Called once a circuit to a rendezvous point is established: sends a + * RELAY_COMMAND_RENDEZVOUS1 cell. + */ +void +rend_service_rendezvous_has_opened(origin_circuit_t *circuit) +{ + rend_service_t *service; + char buf[RELAY_PAYLOAD_SIZE]; + crypt_path_t *hop; + char serviceid[REND_SERVICE_ID_LEN_BASE32+1]; + char hexcookie[9]; + int reason; + const char *rend_cookie, *rend_pk_digest; + + tor_assert(circuit->base_.purpose == CIRCUIT_PURPOSE_S_CONNECT_REND); + tor_assert(circuit->cpath); + tor_assert(circuit->build_state); + assert_circ_anonymity_ok(circuit, get_options()); + tor_assert(circuit->rend_data); + + /* XXX: This is version 2 specific (only one supported). */ + rend_pk_digest = (char *) rend_data_get_pk_digest(circuit->rend_data, + NULL); + rend_cookie = circuit->rend_data->rend_cookie; + + /* Declare the circuit dirty to avoid reuse, and for path-bias. We set the + * timestamp regardless of its content because that circuit could have been + * cannibalized so in any cases, we are about to use that circuit more. */ + circuit->base_.timestamp_dirty = time(NULL); + + /* This may be redundant */ + pathbias_count_use_attempt(circuit); + + hop = circuit->build_state->service_pending_final_cpath_ref->cpath; + + base16_encode(hexcookie,9, rend_cookie,4); + base32_encode(serviceid, REND_SERVICE_ID_LEN_BASE32+1, + rend_pk_digest, REND_SERVICE_ID_LEN); + + log_info(LD_REND, + "Done building circuit %u to rendezvous with " + "cookie %s for service %s", + (unsigned)circuit->base_.n_circ_id, hexcookie, serviceid); + circuit_log_path(LOG_INFO, LD_REND, circuit); + + /* Clear the 'in-progress HS circ has timed out' flag for + * consistency with what happens on the client side; this line has + * no effect on Tor's behaviour. */ + circuit->hs_circ_has_timed_out = 0; + + /* If hop is NULL, another rend circ has already connected to this + * rend point. Close this circ. */ + if (hop == NULL) { + log_info(LD_REND, "Another rend circ has already reached this rend point; " + "closing this rend circ."); + reason = END_CIRC_REASON_NONE; + goto err; + } + + /* Remove our final cpath element from the reference, so that no + * other circuit will try to use it. Store it in + * pending_final_cpath for now to ensure that it will be freed if + * our rendezvous attempt fails. */ + circuit->build_state->pending_final_cpath = hop; + circuit->build_state->service_pending_final_cpath_ref->cpath = NULL; + + service = rend_service_get_by_pk_digest(rend_pk_digest); + if (!service) { + log_warn(LD_GENERAL, "Internal error: unrecognized service ID on " + "rendezvous circuit."); + reason = END_CIRC_REASON_INTERNAL; + goto err; + } + + /* All we need to do is send a RELAY_RENDEZVOUS1 cell... */ + memcpy(buf, rend_cookie, REND_COOKIE_LEN); + if (crypto_dh_get_public(hop->rend_dh_handshake_state, + buf+REND_COOKIE_LEN, DH1024_KEY_LEN)<0) { + log_warn(LD_GENERAL,"Couldn't get DH public key."); + reason = END_CIRC_REASON_INTERNAL; + goto err; + } + memcpy(buf+REND_COOKIE_LEN+DH1024_KEY_LEN, hop->rend_circ_nonce, + DIGEST_LEN); + + /* Send the cell */ + if (relay_send_command_from_edge(0, TO_CIRCUIT(circuit), + RELAY_COMMAND_RENDEZVOUS1, + buf, HS_LEGACY_RENDEZVOUS_CELL_SIZE, + circuit->cpath->prev)<0) { + log_warn(LD_GENERAL, "Couldn't send RENDEZVOUS1 cell."); + goto done; + } + + crypto_dh_free(hop->rend_dh_handshake_state); + hop->rend_dh_handshake_state = NULL; + + /* Append the cpath entry. */ + hop->state = CPATH_STATE_OPEN; + /* set the windows to default. these are the windows + * that the service thinks the client has. + */ + hop->package_window = circuit_initial_package_window(); + hop->deliver_window = CIRCWINDOW_START; + + onion_append_to_cpath(&circuit->cpath, hop); + circuit->build_state->pending_final_cpath = NULL; /* prevent double-free */ + + /* Change the circuit purpose. */ + circuit_change_purpose(TO_CIRCUIT(circuit), CIRCUIT_PURPOSE_S_REND_JOINED); + + goto done; + + err: + circuit_mark_for_close(TO_CIRCUIT(circuit), reason); + done: + memwipe(buf, 0, sizeof(buf)); + memwipe(serviceid, 0, sizeof(serviceid)); + memwipe(hexcookie, 0, sizeof(hexcookie)); + + return; +} + +/* + * Manage introduction points + */ + +/** Return the (possibly non-open) introduction circuit ending at + * intro for the service whose public key is pk_digest. + * (desc_version is ignored). Return NULL if no such service is + * found. + */ +static origin_circuit_t * +find_intro_circuit(rend_intro_point_t *intro, const char *pk_digest) +{ + origin_circuit_t *circ = NULL; + + tor_assert(intro); + while ((circ = circuit_get_next_by_pk_and_purpose(circ, + (uint8_t *) pk_digest, CIRCUIT_PURPOSE_S_INTRO))) { + if (tor_memeq(circ->build_state->chosen_exit->identity_digest, + intro->extend_info->identity_digest, DIGEST_LEN) && + circ->rend_data) { + return circ; + } + } + + circ = NULL; + while ((circ = circuit_get_next_by_pk_and_purpose(circ, + (uint8_t *) pk_digest, + CIRCUIT_PURPOSE_S_ESTABLISH_INTRO))) { + if (tor_memeq(circ->build_state->chosen_exit->identity_digest, + intro->extend_info->identity_digest, DIGEST_LEN) && + circ->rend_data) { + return circ; + } + } + return NULL; +} + +/** Return the corresponding introdution point using the circuit circ + * found in the service. NULL is returned if not found. */ +static rend_intro_point_t * +find_expiring_intro_point(rend_service_t *service, origin_circuit_t *circ) +{ + tor_assert(service); + tor_assert(TO_CIRCUIT(circ)->purpose == CIRCUIT_PURPOSE_S_ESTABLISH_INTRO || + TO_CIRCUIT(circ)->purpose == CIRCUIT_PURPOSE_S_INTRO); + + SMARTLIST_FOREACH(service->expiring_nodes, rend_intro_point_t *, + intro_point, + if (crypto_pk_eq_keys(intro_point->intro_key, circ->intro_key)) { + return intro_point; + }); + + return NULL; +} + +/** Return a pointer to the rend_intro_point_t corresponding to the + * service-side introduction circuit circ. */ +static rend_intro_point_t * +find_intro_point(origin_circuit_t *circ) +{ + const char *serviceid; + rend_service_t *service = NULL; + + tor_assert(TO_CIRCUIT(circ)->purpose == CIRCUIT_PURPOSE_S_ESTABLISH_INTRO || + TO_CIRCUIT(circ)->purpose == CIRCUIT_PURPOSE_S_INTRO); + tor_assert(circ->rend_data); + serviceid = rend_data_get_address(circ->rend_data); + + SMARTLIST_FOREACH(rend_service_list, rend_service_t *, s, + if (tor_memeq(s->service_id, serviceid, REND_SERVICE_ID_LEN_BASE32)) { + service = s; + break; + }); + + if (service == NULL) return NULL; + + SMARTLIST_FOREACH(service->intro_nodes, rend_intro_point_t *, intro_point, + if (crypto_pk_eq_keys(intro_point->intro_key, circ->intro_key)) { + return intro_point; + }); + + return NULL; +} + +/** Upload the rend_encoded_v2_service_descriptor_t's in descs + * associated with the rend_service_descriptor_t renddesc to + * the responsible hidden service directories OR the hidden service + * directories specified by hs_dirs; service_id and + * seconds_valid are only passed for logging purposes. + */ +void +directory_post_to_hs_dir(rend_service_descriptor_t *renddesc, + smartlist_t *descs, smartlist_t *hs_dirs, + const char *service_id, int seconds_valid) +{ + int i, j, failed_upload = 0; + smartlist_t *responsible_dirs = smartlist_new(); + smartlist_t *successful_uploads = smartlist_new(); + routerstatus_t *hs_dir; + for (i = 0; i < smartlist_len(descs); i++) { + rend_encoded_v2_service_descriptor_t *desc = smartlist_get(descs, i); + /** If any HSDirs are specified, they should be used instead of + * the responsible directories */ + if (hs_dirs && smartlist_len(hs_dirs) > 0) { + smartlist_add_all(responsible_dirs, hs_dirs); + } else { + /* Determine responsible dirs. */ + if (hid_serv_get_responsible_directories(responsible_dirs, + desc->desc_id) < 0) { + log_warn(LD_REND, "Could not determine the responsible hidden service " + "directories to post descriptors to."); + control_event_hs_descriptor_upload(service_id, + "UNKNOWN", + "UNKNOWN", NULL); + goto done; + } + } + for (j = 0; j < smartlist_len(responsible_dirs); j++) { + char desc_id_base32[REND_DESC_ID_V2_LEN_BASE32 + 1]; + char *hs_dir_ip; + const node_t *node; + rend_data_t *rend_data; + hs_dir = smartlist_get(responsible_dirs, j); + if (smartlist_contains_digest(renddesc->successful_uploads, + hs_dir->identity_digest)) + /* Don't upload descriptor if we succeeded in doing so last time. */ + continue; + node = node_get_by_id(hs_dir->identity_digest); + if (!node || !node_has_preferred_descriptor(node,0)) { + log_info(LD_REND, "Not launching upload for for v2 descriptor to " + "hidden service directory %s; we don't have its " + "router descriptor. Queuing for later upload.", + safe_str_client(routerstatus_describe(hs_dir))); + failed_upload = -1; + continue; + } + /* Send publish request. */ + + /* We need the service ID to identify which service did the upload + * request. Lookup is made in rend_service_desc_has_uploaded(). */ + rend_data = rend_data_client_create(service_id, desc->desc_id, NULL, + REND_NO_AUTH); + directory_request_t *req = + directory_request_new(DIR_PURPOSE_UPLOAD_RENDDESC_V2); + directory_request_set_routerstatus(req, hs_dir); + directory_request_set_indirection(req, DIRIND_ANONYMOUS); + directory_request_set_payload(req, + desc->desc_str, strlen(desc->desc_str)); + directory_request_set_rend_query(req, rend_data); + directory_initiate_request(req); + directory_request_free(req); + + rend_data_free(rend_data); + base32_encode(desc_id_base32, sizeof(desc_id_base32), + desc->desc_id, DIGEST_LEN); + hs_dir_ip = tor_dup_ip(hs_dir->addr); + log_info(LD_REND, "Launching upload for v2 descriptor for " + "service '%s' with descriptor ID '%s' with validity " + "of %d seconds to hidden service directory '%s' on " + "%s:%d.", + safe_str_client(service_id), + safe_str_client(desc_id_base32), + seconds_valid, + hs_dir->nickname, + hs_dir_ip, + hs_dir->or_port); + control_event_hs_descriptor_upload(service_id, + hs_dir->identity_digest, + desc_id_base32, NULL); + tor_free(hs_dir_ip); + /* Remember successful upload to this router for next time. */ + if (!smartlist_contains_digest(successful_uploads, + hs_dir->identity_digest)) + smartlist_add(successful_uploads, hs_dir->identity_digest); + } + smartlist_clear(responsible_dirs); + } + if (!failed_upload) { + if (renddesc->successful_uploads) { + SMARTLIST_FOREACH(renddesc->successful_uploads, char *, c, tor_free(c);); + smartlist_free(renddesc->successful_uploads); + renddesc->successful_uploads = NULL; + } + renddesc->all_uploads_performed = 1; + } else { + /* Remember which routers worked this time, so that we don't upload the + * descriptor to them again. */ + if (!renddesc->successful_uploads) + renddesc->successful_uploads = smartlist_new(); + SMARTLIST_FOREACH(successful_uploads, const char *, c, { + if (!smartlist_contains_digest(renddesc->successful_uploads, c)) { + char *hsdir_id = tor_memdup(c, DIGEST_LEN); + smartlist_add(renddesc->successful_uploads, hsdir_id); + } + }); + } + done: + smartlist_free(responsible_dirs); + smartlist_free(successful_uploads); +} + +/** Encode and sign an up-to-date service descriptor for service, + * and upload it/them to the responsible hidden service directories. + */ +static void +upload_service_descriptor(rend_service_t *service) +{ + time_t now = time(NULL); + int rendpostperiod; + char serviceid[REND_SERVICE_ID_LEN_BASE32+1]; + int uploaded = 0; + + rendpostperiod = get_options()->RendPostPeriod; + + networkstatus_t *c = networkstatus_get_latest_consensus(); + if (c && smartlist_len(c->routerstatus_list) > 0) { + int seconds_valid, i, j, num_descs; + smartlist_t *descs = smartlist_new(); + smartlist_t *client_cookies = smartlist_new(); + /* Either upload a single descriptor (including replicas) or one + * descriptor for each authorized client in case of authorization + * type 'stealth'. */ + num_descs = service->auth_type == REND_STEALTH_AUTH ? + smartlist_len(service->clients) : 1; + for (j = 0; j < num_descs; j++) { + crypto_pk_t *client_key = NULL; + rend_authorized_client_t *client = NULL; + smartlist_clear(client_cookies); + switch (service->auth_type) { + case REND_NO_AUTH: + /* Do nothing here. */ + break; + case REND_BASIC_AUTH: + SMARTLIST_FOREACH(service->clients, rend_authorized_client_t *, + cl, smartlist_add(client_cookies, cl->descriptor_cookie)); + break; + case REND_STEALTH_AUTH: + client = smartlist_get(service->clients, j); + client_key = client->client_key; + smartlist_add(client_cookies, client->descriptor_cookie); + break; + } + /* Encode the current descriptor. */ + seconds_valid = rend_encode_v2_descriptors(descs, service->desc, + now, 0, + service->auth_type, + client_key, + client_cookies); + if (seconds_valid < 0) { + log_warn(LD_BUG, "Internal error: couldn't encode service " + "descriptor; not uploading."); + smartlist_free(descs); + smartlist_free(client_cookies); + return; + } + rend_get_service_id(service->desc->pk, serviceid); + if (get_options()->PublishHidServDescriptors) { + /* Post the current descriptors to the hidden service directories. */ + log_info(LD_REND, "Launching upload for hidden service %s", + serviceid); + directory_post_to_hs_dir(service->desc, descs, NULL, serviceid, + seconds_valid); + } + /* Free memory for descriptors. */ + for (i = 0; i < smartlist_len(descs); i++) + rend_encoded_v2_service_descriptor_free_(smartlist_get(descs, i)); + smartlist_clear(descs); + /* Update next upload time. */ + if (seconds_valid - REND_TIME_PERIOD_OVERLAPPING_V2_DESCS + > rendpostperiod) + service->next_upload_time = now + rendpostperiod; + else if (seconds_valid < REND_TIME_PERIOD_OVERLAPPING_V2_DESCS) + service->next_upload_time = now + seconds_valid + 1; + else + service->next_upload_time = now + seconds_valid - + REND_TIME_PERIOD_OVERLAPPING_V2_DESCS + 1; + /* Post also the next descriptors, if necessary. */ + if (seconds_valid < REND_TIME_PERIOD_OVERLAPPING_V2_DESCS) { + seconds_valid = rend_encode_v2_descriptors(descs, service->desc, + now, 1, + service->auth_type, + client_key, + client_cookies); + if (seconds_valid < 0) { + log_warn(LD_BUG, "Internal error: couldn't encode service " + "descriptor; not uploading."); + smartlist_free(descs); + smartlist_free(client_cookies); + return; + } + if (get_options()->PublishHidServDescriptors) { + directory_post_to_hs_dir(service->desc, descs, NULL, serviceid, + seconds_valid); + } + /* Free memory for descriptors. */ + for (i = 0; i < smartlist_len(descs); i++) + rend_encoded_v2_service_descriptor_free_(smartlist_get(descs, i)); + smartlist_clear(descs); + } + } + smartlist_free(descs); + smartlist_free(client_cookies); + uploaded = 1; + if (get_options()->PublishHidServDescriptors) { + log_info(LD_REND, "Successfully uploaded v2 rend descriptors!"); + } else { + log_info(LD_REND, "Successfully stored created v2 rend descriptors!"); + } + } + + /* If not uploaded, try again in one minute. */ + if (!uploaded) + service->next_upload_time = now + 60; + + /* Unmark dirty flag of this service. */ + service->desc_is_dirty = 0; +} + +/** Return the number of INTRODUCE2 cells this hidden service has received + * from this intro point. */ +static int +intro_point_accepted_intro_count(rend_intro_point_t *intro) +{ + return intro->accepted_introduce2_count; +} + +/** Return non-zero iff intro should 'expire' now (i.e. we + * should stop publishing it in new descriptors and eventually close + * it). */ +static int +intro_point_should_expire_now(rend_intro_point_t *intro, + time_t now) +{ + tor_assert(intro != NULL); + + if (intro->time_published == -1) { + /* Don't expire an intro point if we haven't even published it yet. */ + return 0; + } + + if (intro_point_accepted_intro_count(intro) >= + intro->max_introductions) { + /* This intro point has been used too many times. Expire it now. */ + return 1; + } + + if (intro->time_to_expire == -1) { + /* This intro point has been published, but we haven't picked an + * expiration time for it. Pick one now. */ + int intro_point_lifetime_seconds = + crypto_rand_int_range(INTRO_POINT_LIFETIME_MIN_SECONDS, + INTRO_POINT_LIFETIME_MAX_SECONDS); + + /* Start the expiration timer now, rather than when the intro + * point was first published. There shouldn't be much of a time + * difference. */ + intro->time_to_expire = now + intro_point_lifetime_seconds; + + return 0; + } + + /* This intro point has a time to expire set already. Use it. */ + return (now >= intro->time_to_expire); +} + +/** Iterate over intro points in the given service and remove the invalid + * ones. For an intro point object to be considered invalid, the circuit + * _and_ node need to have disappeared. + * + * If the intro point should expire, it's placed into the expiring_nodes + * list of the service and removed from the active intro nodes list. + * + * If exclude_nodes is not NULL, add the valid nodes to it. + * + * If retry_nodes is not NULL, add the valid node to it if the + * circuit disappeared but the node is still in the consensus. */ +static void +remove_invalid_intro_points(rend_service_t *service, + smartlist_t *exclude_nodes, + smartlist_t *retry_nodes, time_t now) +{ + tor_assert(service); + + /* Remove any expired nodes that doesn't have a circuit. */ + SMARTLIST_FOREACH_BEGIN(service->expiring_nodes, rend_intro_point_t *, + intro) { + origin_circuit_t *intro_circ = + find_intro_circuit(intro, service->pk_digest); + if (intro_circ) { + continue; + } + /* No more circuit, cleanup the into point object. */ + SMARTLIST_DEL_CURRENT(service->expiring_nodes, intro); + rend_intro_point_free(intro); + } SMARTLIST_FOREACH_END(intro); + + SMARTLIST_FOREACH_BEGIN(service->intro_nodes, rend_intro_point_t *, + intro) { + /* Find the introduction point node object. */ + const node_t *node = + node_get_by_id(intro->extend_info->identity_digest); + /* Find the intro circuit, this might be NULL. */ + origin_circuit_t *intro_circ = + find_intro_circuit(intro, service->pk_digest); + + /* Add the valid node to the exclusion list so we don't try to establish + * an introduction point to it again. */ + if (node && exclude_nodes) { + smartlist_add(exclude_nodes, (void*) node); + } + + /* First, make sure we still have a valid circuit for this intro point. + * If we dont, we'll give up on it and make a new one. */ + if (intro_circ == NULL) { + log_info(LD_REND, "Attempting to retry on %s as intro point for %s" + " (circuit disappeared).", + safe_str_client(extend_info_describe(intro->extend_info)), + safe_str_client(service->service_id)); + /* We've lost the circuit for this intro point, flag it so it can be + * accounted for when considiring uploading a descriptor. */ + intro->circuit_established = 0; + + /* Node is gone or we've reached our maximum circuit creationg retry + * count, clean up everything, we'll find a new one. */ + if (node == NULL || + intro->circuit_retries >= MAX_INTRO_POINT_CIRCUIT_RETRIES) { + rend_intro_point_free(intro); + SMARTLIST_DEL_CURRENT(service->intro_nodes, intro); + /* We've just killed the intro point, nothing left to do. */ + continue; + } + + /* The intro point is still alive so let's try to use it again because + * we have a published descriptor containing it. Keep the intro point + * in the intro_nodes list because it's still valid, we are rebuilding + * a circuit to it. */ + if (retry_nodes) { + smartlist_add(retry_nodes, intro); + } + } + /* else, the circuit is valid so in both cases, node being alive or not, + * we leave the circuit and intro point object as is. Closing the + * circuit here would leak new consensus timing and freeing the intro + * point object would make the intro circuit unusable. */ + + /* Now, check if intro point should expire. If it does, queue it so + * it can be cleaned up once it has been replaced properly. */ + if (intro_point_should_expire_now(intro, now)) { + log_info(LD_REND, "Expiring %s as intro point for %s.", + safe_str_client(extend_info_describe(intro->extend_info)), + safe_str_client(service->service_id)); + /* We might have put it in the retry list if so, undo. */ + if (retry_nodes) { + smartlist_remove(retry_nodes, intro); + } + smartlist_add(service->expiring_nodes, intro); + SMARTLIST_DEL_CURRENT(service->intro_nodes, intro); + /* Intro point is expired, we need a new one thus don't consider it + * anymore has a valid established intro point. */ + intro->circuit_established = 0; + } + } SMARTLIST_FOREACH_END(intro); +} + +/** A new descriptor has been successfully uploaded for the given + * rend_data. Remove and free the expiring nodes from the associated + * service. */ +void +rend_service_desc_has_uploaded(const rend_data_t *rend_data) +{ + rend_service_t *service; + const char *onion_address; + + tor_assert(rend_data); + + onion_address = rend_data_get_address(rend_data); + + service = rend_service_get_by_service_id(onion_address); + if (service == NULL) { + return; + } + + SMARTLIST_FOREACH_BEGIN(service->expiring_nodes, rend_intro_point_t *, + intro) { + origin_circuit_t *intro_circ = + find_intro_circuit(intro, service->pk_digest); + if (intro_circ != NULL) { + circuit_mark_for_close(TO_CIRCUIT(intro_circ), + END_CIRC_REASON_FINISHED); + } + SMARTLIST_DEL_CURRENT(service->expiring_nodes, intro); + rend_intro_point_free(intro); + } SMARTLIST_FOREACH_END(intro); +} + +/** Don't try to build more than this many circuits before giving up + * for a while. Dynamically calculated based on the configured number of + * introduction points for the service, n_intro_points_wanted. */ +static int +rend_max_intro_circs_per_period(unsigned int n_intro_points_wanted) +{ + /* Allow all but one of the initial connections to fail and be + * retried. (If all fail, we *want* to wait, because something is broken.) */ + tor_assert(n_intro_points_wanted <= NUM_INTRO_POINTS_MAX); + + /* For the normal use case, 3 intro points plus 2 extra for performance and + * allow that twice because once every 24h or so, we can do it twice for two + * descriptors that is the current one and the next one. So (3 + 2) * 2 == + * 12 allowed attempts for one period. */ + return ((n_intro_points_wanted + NUM_INTRO_POINTS_EXTRA) * 2); +} + +/** For every service, check how many intro points it currently has, and: + * - Invalidate introdution points based on specific criteria, see + * remove_invalid_intro_points comments. + * - Pick new intro points as necessary. + * - Launch circuits to any new intro points. + * + * This is called once a second by the main loop. + */ +void +rend_consider_services_intro_points(time_t now) +{ + int i; + const or_options_t *options = get_options(); + /* Are we in single onion mode? */ + const int allow_direct = rend_service_allow_non_anonymous_connection( + get_options()); + /* List of nodes we need to _exclude_ when choosing a new node to + * establish an intro point to. */ + smartlist_t *exclude_nodes; + /* List of nodes we need to retry to build a circuit on them because the + * node is valid but circuit died. */ + smartlist_t *retry_nodes; + + if (!have_completed_a_circuit()) + return; + + exclude_nodes = smartlist_new(); + retry_nodes = smartlist_new(); + + SMARTLIST_FOREACH_BEGIN(rend_service_list, rend_service_t *, service) { + int r; + /* Number of intro points we want to open and add to the intro nodes + * list of the service. */ + unsigned int n_intro_points_to_open; + /* Have an unsigned len so we can use it to compare values else gcc is + * not happy with unmatching signed comparaison. */ + unsigned int intro_nodes_len; + /* Different service are allowed to have the same introduction point as + * long as they are on different circuit thus why we clear this list. */ + smartlist_clear(exclude_nodes); + smartlist_clear(retry_nodes); + + /* Cleanup the invalid intro points and save the node objects, if any, + * in the exclude_nodes and retry_nodes lists. */ + remove_invalid_intro_points(service, exclude_nodes, retry_nodes, now); + + /* This retry period is important here so we don't stress circuit + * creation. */ + + if (now > service->intro_period_started + INTRO_CIRC_RETRY_PERIOD) { + /* One period has elapsed: + * - if we stopped, we can try building circuits again, + * - if we haven't, we reset the circuit creation counts. */ + rend_log_intro_limit(service, LOG_INFO); + service->intro_period_started = now; + service->n_intro_circuits_launched = 0; + } else if (service->n_intro_circuits_launched >= + rend_max_intro_circs_per_period( + service->n_intro_points_wanted)) { + /* We have failed too many times in this period; wait for the next + * one before we try to initiate any more connections. */ + rend_log_intro_limit(service, LOG_WARN); + continue; + } + + /* Let's try to rebuild circuit on the nodes we want to retry on. */ + SMARTLIST_FOREACH_BEGIN(retry_nodes, rend_intro_point_t *, intro) { + r = rend_service_launch_establish_intro(service, intro); + if (r < 0) { + log_warn(LD_REND, "Error launching circuit to node %s for service %s.", + safe_str_client(extend_info_describe(intro->extend_info)), + safe_str_client(service->service_id)); + /* Unable to launch a circuit to that intro point, remove it from + * the valid list so we can create a new one. */ + smartlist_remove(service->intro_nodes, intro); + rend_intro_point_free(intro); + continue; + } + intro->circuit_retries++; + } SMARTLIST_FOREACH_END(intro); + + /* Avoid mismatched signed comparaison below. */ + intro_nodes_len = (unsigned int) smartlist_len(service->intro_nodes); + + /* Quiescent state, we have more or the equal amount of wanted node for + * this service. Proceed to the next service. We can have more nodes + * because we launch extra preemptive circuits if our intro nodes list was + * originally empty for performance reasons. */ + if (intro_nodes_len >= service->n_intro_points_wanted) { + continue; + } + + /* Number of intro points we want to open which is the wanted amount minus + * the current amount of valid nodes. We know that this won't underflow + * because of the check above. */ + n_intro_points_to_open = service->n_intro_points_wanted - intro_nodes_len; + if (intro_nodes_len == 0) { + /* We want to end up with n_intro_points_wanted intro points, but if + * we have no intro points at all (chances are they all cycled or we + * are starting up), we launch NUM_INTRO_POINTS_EXTRA extra circuits + * and use the first n_intro_points_wanted that complete. See proposal + * #155, section 4 for the rationale of this which is purely for + * performance. + * + * The ones after the first n_intro_points_to_open will be converted + * to 'general' internal circuits in rend_service_intro_has_opened(), + * and then we'll drop them from the list of intro points. */ + n_intro_points_to_open += NUM_INTRO_POINTS_EXTRA; + } + + for (i = 0; i < (int) n_intro_points_to_open; i++) { + const node_t *node; + rend_intro_point_t *intro; + router_crn_flags_t flags = CRN_NEED_UPTIME|CRN_NEED_DESC; + router_crn_flags_t direct_flags = flags; + direct_flags |= CRN_PREF_ADDR; + direct_flags |= CRN_DIRECT_CONN; + + node = router_choose_random_node(exclude_nodes, + options->ExcludeNodes, + allow_direct ? direct_flags : flags); + /* If we are in single onion mode, retry node selection for a 3-hop + * path */ + if (allow_direct && !node) { + log_info(LD_REND, + "Unable to find an intro point that we can connect to " + "directly for %s, falling back to a 3-hop path.", + safe_str_client(service->service_id)); + node = router_choose_random_node(exclude_nodes, + options->ExcludeNodes, flags); + } + + if (!node) { + log_warn(LD_REND, + "We only have %d introduction points established for %s; " + "wanted %u.", + smartlist_len(service->intro_nodes), + safe_str_client(service->service_id), + n_intro_points_to_open); + break; + } + /* Add the chosen node to the exclusion list in order to avoid picking + * it again in the next iteration. */ + smartlist_add(exclude_nodes, (void*)node); + intro = tor_malloc_zero(sizeof(rend_intro_point_t)); + /* extend_info is for clients, so we want the multi-hop primary ORPort, + * even if we are a single onion service and intend to connect to it + * directly ourselves. */ + intro->extend_info = extend_info_from_node(node, 0); + if (BUG(intro->extend_info == NULL)) { + break; + } + intro->intro_key = crypto_pk_new(); + const int fail = crypto_pk_generate_key(intro->intro_key); + tor_assert(!fail); + intro->time_published = -1; + intro->time_to_expire = -1; + intro->max_introductions = + crypto_rand_int_range(INTRO_POINT_MIN_LIFETIME_INTRODUCTIONS, + INTRO_POINT_MAX_LIFETIME_INTRODUCTIONS); + smartlist_add(service->intro_nodes, intro); + log_info(LD_REND, "Picked router %s as an intro point for %s.", + safe_str_client(node_describe(node)), + safe_str_client(service->service_id)); + /* Establish new introduction circuit to our chosen intro point. */ + r = rend_service_launch_establish_intro(service, intro); + if (r < 0) { + log_warn(LD_REND, "Error launching circuit to node %s for service %s.", + safe_str_client(extend_info_describe(intro->extend_info)), + safe_str_client(service->service_id)); + /* This funcion will be called again by the main loop so this intro + * point without a intro circuit will be retried on or removed after + * a maximum number of attempts. */ + } + } + } SMARTLIST_FOREACH_END(service); + smartlist_free(exclude_nodes); + smartlist_free(retry_nodes); +} + +#define MIN_REND_INITIAL_POST_DELAY (30) +#define MIN_REND_INITIAL_POST_DELAY_TESTING (5) + +/** Regenerate and upload rendezvous service descriptors for all + * services, if necessary. If the descriptor has been dirty enough + * for long enough, definitely upload; else only upload when the + * periodic timeout has expired. + * + * For the first upload, pick a random time between now and two periods + * from now, and pick it independently for each service. + */ +void +rend_consider_services_upload(time_t now) +{ + int i; + rend_service_t *service; + const or_options_t *options = get_options(); + int rendpostperiod = options->RendPostPeriod; + int rendinitialpostdelay = (options->TestingTorNetwork ? + MIN_REND_INITIAL_POST_DELAY_TESTING : + MIN_REND_INITIAL_POST_DELAY); + + for (i=0; i < smartlist_len(rend_service_list); ++i) { + service = smartlist_get(rend_service_list, i); + if (!service->next_upload_time) { /* never been uploaded yet */ + /* The fixed lower bound of rendinitialpostdelay seconds ensures that + * the descriptor is stable before being published. See comment below. */ + service->next_upload_time = + now + rendinitialpostdelay + crypto_rand_int(2*rendpostperiod); + /* Single Onion Services prioritise availability over hiding their + * startup time, as their IP address is publicly discoverable anyway. + */ + if (rend_service_reveal_startup_time(options)) { + service->next_upload_time = now + rendinitialpostdelay; + } + } + /* Does every introduction points have been established? */ + unsigned int intro_points_ready = + count_established_intro_points(service) >= + service->n_intro_points_wanted; + if (intro_points_ready && + (service->next_upload_time < now || + (service->desc_is_dirty && + service->desc_is_dirty < now-rendinitialpostdelay))) { + /* if it's time, or if the directory servers have a wrong service + * descriptor and ours has been stable for rendinitialpostdelay seconds, + * upload a new one of each format. */ + rend_service_update_descriptor(service); + upload_service_descriptor(service); + } + } +} + +/** True if the list of available router descriptors might have changed so + * that we should have a look whether we can republish previously failed + * rendezvous service descriptors. */ +static int consider_republishing_rend_descriptors = 1; + +/** Called when our internal view of the directory has changed, so that we + * might have router descriptors of hidden service directories available that + * we did not have before. */ +void +rend_hsdir_routers_changed(void) +{ + consider_republishing_rend_descriptors = 1; +} + +/** Consider republication of v2 rendezvous service descriptors that failed + * previously, but without regenerating descriptor contents. + */ +void +rend_consider_descriptor_republication(void) +{ + int i; + rend_service_t *service; + + if (!consider_republishing_rend_descriptors) + return; + consider_republishing_rend_descriptors = 0; + + if (!get_options()->PublishHidServDescriptors) + return; + + for (i=0; i < smartlist_len(rend_service_list); ++i) { + service = smartlist_get(rend_service_list, i); + if (service->desc && !service->desc->all_uploads_performed) { + /* If we failed in uploading a descriptor last time, try again *without* + * updating the descriptor's contents. */ + upload_service_descriptor(service); + } + } +} + +/** Log the status of introduction points for all rendezvous services + * at log severity severity. + */ +void +rend_service_dump_stats(int severity) +{ + int i,j; + rend_service_t *service; + rend_intro_point_t *intro; + const char *safe_name; + origin_circuit_t *circ; + + for (i=0; i < smartlist_len(rend_service_list); ++i) { + service = smartlist_get(rend_service_list, i); + tor_log(severity, LD_GENERAL, "Service configured in %s:", + rend_service_escaped_dir(service)); + for (j=0; j < smartlist_len(service->intro_nodes); ++j) { + intro = smartlist_get(service->intro_nodes, j); + safe_name = safe_str_client(intro->extend_info->nickname); + + circ = find_intro_circuit(intro, service->pk_digest); + if (!circ) { + tor_log(severity, LD_GENERAL, " Intro point %d at %s: no circuit", + j, safe_name); + continue; + } + tor_log(severity, LD_GENERAL, " Intro point %d at %s: circuit is %s", + j, safe_name, circuit_state_to_string(circ->base_.state)); + } + } +} + +/** Given conn, a rendezvous exit stream, look up the hidden service for + * circ, and look up the port and address based on conn-\>port. + * Assign the actual conn-\>addr and conn-\>port. Return -2 on failure + * for which the circuit should be closed, -1 on other failure, + * or 0 for success. + */ +int +rend_service_set_connection_addr_port(edge_connection_t *conn, + origin_circuit_t *circ) +{ + rend_service_t *service; + char serviceid[REND_SERVICE_ID_LEN_BASE32+1]; + const char *rend_pk_digest; + + tor_assert(circ->base_.purpose == CIRCUIT_PURPOSE_S_REND_JOINED); + tor_assert(circ->rend_data); + log_debug(LD_REND,"beginning to hunt for addr/port"); + rend_pk_digest = (char *) rend_data_get_pk_digest(circ->rend_data, NULL); + base32_encode(serviceid, REND_SERVICE_ID_LEN_BASE32+1, + rend_pk_digest, REND_SERVICE_ID_LEN); + service = rend_service_get_by_pk_digest(rend_pk_digest); + if (!service) { + log_warn(LD_REND, "Couldn't find any service associated with pk %s on " + "rendezvous circuit %u; closing.", + serviceid, (unsigned)circ->base_.n_circ_id); + return -2; + } + if (service->max_streams_per_circuit > 0) { + /* Enforce the streams-per-circuit limit, and refuse to provide a + * mapping if this circuit will exceed the limit. */ +#define MAX_STREAM_WARN_INTERVAL 600 + static struct ratelim_t stream_ratelim = + RATELIM_INIT(MAX_STREAM_WARN_INTERVAL); + if (circ->rend_data->nr_streams >= service->max_streams_per_circuit) { + log_fn_ratelim(&stream_ratelim, LOG_WARN, LD_REND, + "Maximum streams per circuit limit reached on rendezvous " + "circuit %u; %s. Circuit has %d out of %d streams.", + (unsigned)circ->base_.n_circ_id, + service->max_streams_close_circuit ? + "closing circuit" : + "ignoring open stream request", + circ->rend_data->nr_streams, + service->max_streams_per_circuit); + return service->max_streams_close_circuit ? -2 : -1; + } + } + + if (hs_set_conn_addr_port(service->ports, conn) == 0) { + /* Successfully set the port to the connection. We are done. */ + return 0; + } + + log_info(LD_REND, + "No virtual port mapping exists for port %d on service %s", + conn->base_.port, serviceid); + + if (service->allow_unknown_ports) + return -1; + else + return -2; +} + +/* Are HiddenServiceSingleHopMode and HiddenServiceNonAnonymousMode consistent? + */ +static int +rend_service_non_anonymous_mode_consistent(const or_options_t *options) +{ + /* !! is used to make these options boolean */ + return (!! options->HiddenServiceSingleHopMode == + !! options->HiddenServiceNonAnonymousMode); +} + +/* Do the options allow onion services to make direct (non-anonymous) + * connections to introduction or rendezvous points? + * Must only be called after options_validate_single_onion() has successfully + * checked onion service option consistency. + * Returns true if tor is in HiddenServiceSingleHopMode. */ +int +rend_service_allow_non_anonymous_connection(const or_options_t *options) +{ + tor_assert(rend_service_non_anonymous_mode_consistent(options)); + return options->HiddenServiceSingleHopMode ? 1 : 0; +} + +/* Do the options allow us to reveal the exact startup time of the onion + * service? + * Single Onion Services prioritise availability over hiding their + * startup time, as their IP address is publicly discoverable anyway. + * Must only be called after options_validate_single_onion() has successfully + * checked onion service option consistency. + * Returns true if tor is in non-anonymous hidden service mode. */ +int +rend_service_reveal_startup_time(const or_options_t *options) +{ + tor_assert(rend_service_non_anonymous_mode_consistent(options)); + return rend_service_non_anonymous_mode_enabled(options); +} + +/* Is non-anonymous mode enabled using the HiddenServiceNonAnonymousMode + * config option? + * Must only be called after options_validate_single_onion() has successfully + * checked onion service option consistency. + */ +int +rend_service_non_anonymous_mode_enabled(const or_options_t *options) +{ + tor_assert(rend_service_non_anonymous_mode_consistent(options)); + return options->HiddenServiceNonAnonymousMode ? 1 : 0; +} + +#ifdef TOR_UNIT_TESTS + +STATIC void +set_rend_service_list(smartlist_t *new_list) +{ + rend_service_list = new_list; +} + +STATIC void +set_rend_rend_service_staging_list(smartlist_t *new_list) +{ + rend_service_staging_list = new_list; +} + +#endif /* defined(TOR_UNIT_TESTS) */

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[tor/master] rendservice: Always use a 3-hop path when a v2 single onion rend fails
by dgoulet＠torproject.org 29 Aug '19

29 Aug '19

commit dc08f8ac70e95b9a76f86a5e15dfcabd7ada25b9 Author: teor <teor(a)torproject.org> Date: Fri Aug 23 14:38:54 2019 +1000 rendservice: Always use a 3-hop path when a v2 single onion rend fails Previously, we used a 1-hop path when a single onion rend failed immediately, and a 3-hop path when it failed after trying to build a circuit. Fixes bug 23818; bugfix on 0.2.9.3-alpha. --- src/or/rendservice.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/src/or/rendservice.c b/src/or/rendservice.c index 32b856452..f145e9d69 100644 --- a/src/or/rendservice.c +++ b/src/or/rendservice.c @@ -2073,8 +2073,12 @@ rend_service_receive_introduction(origin_circuit_t *circuit, int flags = CIRCLAUNCH_NEED_CAPACITY | CIRCLAUNCH_IS_INTERNAL; if (circ_needs_uptime) flags |= CIRCLAUNCH_NEED_UPTIME; /* A Single Onion Service only uses a direct connection if its - * firewall rules permit direct connections to the address. */ - if (rend_service_use_direct_connection(options, rp)) { + * firewall rules permit direct connections to the address. + * + * We only use a one-hop path on the first attempt. If the first attempt + * fails, we use a 3-hop path for reachability / reliability. + * See the comment in rend_service_relauch_rendezvous() for details. */ + if (rend_service_use_direct_connection(options, rp) && i == 0) { flags = flags | CIRCLAUNCH_ONEHOP_TUNNEL; } launched = circuit_launch_by_extend_info(

1 0

[tor/master] rendservice: Always use a 3-hop path when a v2 single onion intro fails
by dgoulet＠torproject.org 29 Aug '19

29 Aug '19

commit 144084d6facc3d688c7d423a8b5b8da5e26de84c Author: teor <teor(a)torproject.org> Date: Fri Aug 23 14:54:15 2019 +1000 rendservice: Always use a 3-hop path when a v2 single onion intro fails Previously, we always used a 1-hop path, no matter how many times a v2 single onion intro failed. Fixes bug 23818; bugfix on 0.2.9.3-alpha. --- src/or/rendservice.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/src/or/rendservice.c b/src/or/rendservice.c index f145e9d69..ca1be5e5d 100644 --- a/src/or/rendservice.c +++ b/src/or/rendservice.c @@ -3041,8 +3041,15 @@ rend_service_launch_establish_intro(rend_service_t *service, extend_info_t *launch_ei = intro->extend_info; extend_info_t *direct_ei = NULL; - /* Are we in single onion mode? */ - if (rend_service_allow_non_anonymous_connection(options)) { + /* Are we in single onion mode? + * + * We only use a one-hop path on the first attempt. If the first attempt + * fails, we use a 3-hop path for reachability / reliability. + * (Unlike v3, retries is incremented by the caller after it calls this + * function.) + */ + if (rend_service_allow_non_anonymous_connection(options) && + intro->circuit_retries == 0) { /* Do we have a descriptor for the node? * We've either just chosen it from the consensus, or we've just reviewed * our intro points to see which ones are still valid, and deleted the ones

1 0

[tor/master] changes: file for 23507, v3 onion service fix
by dgoulet＠torproject.org 29 Aug '19

29 Aug '19

commit 41bc1fac8e77e399572e020c5ba59462afd75f4b Author: teor <teor(a)torproject.org> Date: Fri Aug 23 16:25:33 2019 +1000 changes: file for 23507, v3 onion service fix --- changes/bug23507 | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/changes/bug23507 b/changes/bug23507 new file mode 100644 index 000000000..de18273fd --- /dev/null +++ b/changes/bug23507 @@ -0,0 +1,5 @@ + o Minor bugfixes (v3 single onion services): + - Make v3 single onion services fall back to a 3-hop intro, when there + all intro points are unreachable via a 1-hop path. Previously, v3 + single onion services failed when all intro nodes were unreachable + via a 1-hop path. Fixes bug 23507; bugfix on 0.3.2.1-alpha.

1 0

[tor/master] changes: file for 23818, v3 onion service fix
by dgoulet＠torproject.org 29 Aug '19

29 Aug '19

commit 084245134b022aa983c45aa3fc0ace9fd7ae21a9 Author: teor <teor(a)torproject.org> Date: Fri Aug 23 15:10:45 2019 +1000 changes: file for 23818, v3 onion service fix --- changes/bug23818_v3 | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/changes/bug23818_v3 b/changes/bug23818_v3 new file mode 100644 index 000000000..c430144d8 --- /dev/null +++ b/changes/bug23818_v3 @@ -0,0 +1,6 @@ + o Minor bugfixes (v3 single onion services): + - Always retry v3 single onion service intro and rend circuits with a + 3-hop path. Previously, v3 single onion services used a 3-hop path + when rend circuits were retried after a remote or delayed failure, + but a 1-hop path for immediate retries. Fixes bug 23818; + bugfix on 0.3.2.1-alpha.

1 0

[tor/master] hs: Always use a 3-hop path when a v3 single onion intro fails
by dgoulet＠torproject.org 29 Aug '19

29 Aug '19

commit 229a982405e0fd2f9980d3c1a41c34e0cf26ae26 Author: teor <teor(a)torproject.org> Date: Fri Aug 23 14:56:01 2019 +1000 hs: Always use a 3-hop path when a v3 single onion intro fails Previously, we always used a 1-hop path, no matter how many times a v3 single onion intro failed. Fixes bug 23818; bugfix on 0.3.2.1-alpha. --- src/feature/hs/hs_circuit.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/src/feature/hs/hs_circuit.c b/src/feature/hs/hs_circuit.c index f7996a24f..d74b088f0 100644 --- a/src/feature/hs/hs_circuit.c +++ b/src/feature/hs/hs_circuit.c @@ -775,8 +775,15 @@ hs_circ_launch_intro_point(hs_service_t *service, tor_assert(ei); /* Update circuit flags in case of a single onion service that requires a - * direct connection. */ - if (service->config.is_single_onion) { + * direct connection. + * + * We only use a one-hop path on the first attempt. If the first attempt + * fails, we use a 3-hop path for reachability / reliability. + * (Unlike v2, retries is incremented by the caller before it calls this + * function.) + */ + tor_assert_nonfatal(ip->circuit_retries > 0); + if (service->config.is_single_onion && ip->circuit_retries == 1) { circ_flags |= CIRCLAUNCH_ONEHOP_TUNNEL; }

1 0

[tor/master] hs: Always use a 3-hop path when a v3 single onion rend fails
by dgoulet＠torproject.org 29 Aug '19

29 Aug '19

commit c94904b35982a73a652d9bed8b195ce625bbb962 Author: teor <teor(a)torproject.org> Date: Fri Aug 23 14:41:24 2019 +1000 hs: Always use a 3-hop path when a v3 single onion rend fails Previously, we used a 1-hop path when a single onion rend failed immediately, and a 3-hop path when it failed after trying to build a circuit. Fixes bug 23818; bugfix on 0.3.2.1-alpha. --- src/feature/hs/hs_circuit.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/src/feature/hs/hs_circuit.c b/src/feature/hs/hs_circuit.c index e3873d2f1..f7996a24f 100644 --- a/src/feature/hs/hs_circuit.c +++ b/src/feature/hs/hs_circuit.c @@ -405,8 +405,12 @@ launch_rendezvous_point_circuit(const hs_service_t *service, if (circ_needs_uptime) { circ_flags |= CIRCLAUNCH_NEED_UPTIME; } - /* Firewall and policies are checked when getting the extend info. */ - if (service->config.is_single_onion) { + /* Firewall and policies are checked when getting the extend info. + * + * We only use a one-hop path on the first attempt. If the first attempt + * fails, we use a 3-hop path for reachability / reliability. + * See the comment in retry_service_rendezvous_point() for details. */ + if (service->config.is_single_onion && i == 0) { circ_flags |= CIRCLAUNCH_ONEHOP_TUNNEL; }

1 0

[tor/master] hs: v3 single onion services fall back to 3-hop intro for unreachable nodes
by dgoulet＠torproject.org 29 Aug '19

29 Aug '19

commit e2e1c07fd25c96a83b38f5d84d2c063b98ed8f46 Author: teor <teor(a)torproject.org> Date: Fri Aug 23 16:17:47 2019 +1000 hs: v3 single onion services fall back to 3-hop intro for unreachable nodes Previously, v3 single onion services failed when all intro nodes were unreachable via a 1-hop path. Now, we select intros that are only available via a 3-hop path, and use a 3-hop path to connect to them. Fixes bug 23507; bugfix on 0.3.2.1-alpha. --- src/feature/hs/hs_circuit.c | 25 +++++++++++++++---------- src/feature/hs/hs_circuit.h | 3 ++- src/feature/hs/hs_service.c | 30 +++++++++++++++++++++++------- 3 files changed, 40 insertions(+), 18 deletions(-) diff --git a/src/feature/hs/hs_circuit.c b/src/feature/hs/hs_circuit.c index d74b088f0..8acfcbd65 100644 --- a/src/feature/hs/hs_circuit.c +++ b/src/feature/hs/hs_circuit.c @@ -758,13 +758,16 @@ hs_circ_retry_service_rendezvous_point(origin_circuit_t *circ) } /* For a given service and a service intro point, launch a circuit to the - * extend info ei. If the service is a single onion, a one-hop circuit will be - * requested. Return 0 if the circuit was successfully launched and tagged + * extend info ei. If the service is a single onion, and direct_conn is true, + * a one-hop circuit will be requested. + * + * Return 0 if the circuit was successfully launched and tagged * with the correct identifier. On error, a negative value is returned. */ int hs_circ_launch_intro_point(hs_service_t *service, const hs_service_intro_point_t *ip, - extend_info_t *ei) + extend_info_t *ei, + bool direct_conn) { /* Standard flags for introduction circuit. */ int ret = -1, circ_flags = CIRCLAUNCH_NEED_UPTIME | CIRCLAUNCH_IS_INTERNAL; @@ -775,15 +778,17 @@ hs_circ_launch_intro_point(hs_service_t *service, tor_assert(ei); /* Update circuit flags in case of a single onion service that requires a - * direct connection. - * - * We only use a one-hop path on the first attempt. If the first attempt + * direct connection. */ + tor_assert_nonfatal(ip->circuit_retries > 0); + /* Only single onion services can make direct conns */ + if (BUG(!service->config.is_single_onion && direct_conn)) { + goto end; + } + /* We only use a one-hop path on the first attempt. If the first attempt * fails, we use a 3-hop path for reachability / reliability. * (Unlike v2, retries is incremented by the caller before it calls this - * function.) - */ - tor_assert_nonfatal(ip->circuit_retries > 0); - if (service->config.is_single_onion && ip->circuit_retries == 1) { + * function.) */ + if (direct_conn && ip->circuit_retries == 1) { circ_flags |= CIRCLAUNCH_ONEHOP_TUNNEL; } diff --git a/src/feature/hs/hs_circuit.h b/src/feature/hs/hs_circuit.h index b8d8b25ad..e168b301f 100644 --- a/src/feature/hs/hs_circuit.h +++ b/src/feature/hs/hs_circuit.h @@ -26,7 +26,8 @@ void hs_circ_service_rp_has_opened(const hs_service_t *service, origin_circuit_t *circ); int hs_circ_launch_intro_point(hs_service_t *service, const hs_service_intro_point_t *ip, - extend_info_t *ei); + extend_info_t *ei, + bool direct_conn); int hs_circ_launch_rendezvous_point(const hs_service_t *service, const curve25519_public_key_t *onion_key, const uint8_t *rendezvous_cookie); diff --git a/src/feature/hs/hs_service.c b/src/feature/hs/hs_service.c index 402929036..b05f20366 100644 --- a/src/feature/hs/hs_service.c +++ b/src/feature/hs/hs_service.c @@ -2105,6 +2105,7 @@ build_all_descriptors(time_t now) static hs_service_intro_point_t * pick_intro_point(unsigned int direct_conn, smartlist_t *exclude_nodes) { + const or_options_t *options = get_options(); const node_t *node; extend_info_t *info = NULL; hs_service_intro_point_t *ip = NULL; @@ -2113,11 +2114,19 @@ pick_intro_point(unsigned int direct_conn, smartlist_t *exclude_nodes) /* Single onion flags. */ router_crn_flags_t direct_flags = flags | CRN_PREF_ADDR | CRN_DIRECT_CONN; - node = router_choose_random_node(exclude_nodes, get_options()->ExcludeNodes, + node = router_choose_random_node(exclude_nodes, options->ExcludeNodes, direct_conn ? direct_flags : flags); - /* Unable to find a node. When looking for a node for a direct connection, - * we could try a 3-hop path instead. We'll add support for this in a later - * release. */ + + /* If we are in single onion mode, retry node selection for a 3-hop + * path */ + if (direct_conn && !node) { + log_info(LD_REND, + "Unable to find an intro point that we can connect to " + "directly, falling back to a 3-hop path."); + node = router_choose_random_node(exclude_nodes, options->ExcludeNodes, + flags); + } + if (!node) { goto err; } @@ -2644,7 +2653,7 @@ launch_intro_point_circuits(hs_service_t *service) * circuits using the current map. */ FOR_EACH_DESCRIPTOR_BEGIN(service, desc) { /* Keep a ref on if we need a direct connection. We use this often. */ - unsigned int direct_conn = service->config.is_single_onion; + bool direct_conn = service->config.is_single_onion; DIGEST256MAP_FOREACH_MODIFY(desc->intro_points.map, key, hs_service_intro_point_t *, ip) { @@ -2655,8 +2664,15 @@ launch_intro_point_circuits(hs_service_t *service) if (hs_circ_service_get_intro_circ(ip)) { continue; } - ei = get_extend_info_from_intro_point(ip, direct_conn); + + /* If we can't connect directly to the intro point, get an extend_info + * for a multi-hop path instead. */ + if (ei == NULL && direct_conn) { + direct_conn = false; + ei = get_extend_info_from_intro_point(ip, 0); + } + if (ei == NULL) { /* This is possible if we can get a node_t but not the extend info out * of it. In this case, we remove the intro point and a new one will @@ -2668,7 +2684,7 @@ launch_intro_point_circuits(hs_service_t *service) /* Launch a circuit to the intro point. */ ip->circuit_retries++; - if (hs_circ_launch_intro_point(service, ip, ei) < 0) { + if (hs_circ_launch_intro_point(service, ip, ei, direct_conn) < 0) { log_info(LD_REND, "Unable to launch intro circuit to node %s " "for service %s.", safe_str_client(extend_info_describe(ei)),

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[tor/master] Merge branch 'bug23818_035' into bug23818_master
by dgoulet＠torproject.org 29 Aug '19

29 Aug '19

commit 65935f6da7ac9201c6197f4fc1b57527c8e3457a Merge: d475d7c2f 41bc1fac8 Author: teor <teor(a)torproject.org> Date: Fri Aug 23 16:26:32 2019 +1000 Merge branch 'bug23818_035' into bug23818_master changes/bug23507 | 5 +++++ changes/bug23818_v2 | 6 ++++++ changes/bug23818_v3 | 6 ++++++ src/feature/hs/hs_circuit.c | 28 ++++++++++++++++++++++------ src/feature/hs/hs_circuit.h | 3 ++- src/feature/hs/hs_service.c | 30 +++++++++++++++++++++++------- src/feature/rend/rendservice.c | 19 +++++++++++++++---- 7 files changed, 79 insertions(+), 18 deletions(-) diff --cc src/feature/hs/hs_service.c index 8a4f1efb1,b05f20366..283591274 --- a/src/feature/hs/hs_service.c +++ b/src/feature/hs/hs_service.c @@@ -2071,7 -2105,9 +2071,8 @@@ build_all_descriptors(time_t now static hs_service_intro_point_t * pick_intro_point(unsigned int direct_conn, smartlist_t *exclude_nodes) { + const or_options_t *options = get_options(); const node_t *node; - extend_info_t *info = NULL; hs_service_intro_point_t *ip = NULL; /* Normal 3-hop introduction point flags. */ router_crn_flags_t flags = CRN_NEED_UPTIME | CRN_NEED_DESC;

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[tor/master] hs: Remove an outdated comment
by dgoulet＠torproject.org 29 Aug '19

29 Aug '19

commit 55580d063d03ee100a75f4acea8286a6c6e53c8f Author: teor <teor(a)torproject.org> Date: Fri Aug 23 14:43:16 2019 +1000 hs: Remove an outdated comment --- src/feature/hs/hs_circuit.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) diff --git a/src/feature/hs/hs_circuit.c b/src/feature/hs/hs_circuit.c index 716c4b1f1..e3f9ca1de 100644 --- a/src/feature/hs/hs_circuit.c +++ b/src/feature/hs/hs_circuit.c @@ -389,10 +389,7 @@ 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.",

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