commit cdda3dc48457af31a9d1b3df1222d449b736f3b1 Author: teor <teor@torproject.org> Date: Wed Jan 30 15:15:41 2019 +0100 hs: Move get_lspecs_from_node to nodelist.c Also: * rename to node_get_link_specifier_smartlist * rewrite to return a smartlist * add link_specifier_smartlist_free Part of 23576. --- src/feature/hs/hs_circuit.c | 86 ++---------------------------------- src/feature/nodelist/nodelist.c | 96 +++++++++++++++++++++++++++++++++++++++++ src/feature/nodelist/nodelist.h | 5 +++ 3 files changed, 105 insertions(+), 82 deletions(-) diff --git a/src/feature/hs/hs_circuit.c b/src/feature/hs/hs_circuit.c index e3873d2f1..253c24d64 100644 --- a/src/feature/hs/hs_circuit.c +++ b/src/feature/hs/hs_circuit.c @@ -565,81 +565,6 @@ retry_service_rendezvous_point(const origin_circuit_t *circ) return; } -/* Add all possible link specifiers in node to lspecs: - * - legacy ID is mandatory thus MUST be present in node; - * - include ed25519 link specifier if present in the node, and the node - * supports ed25519 link authentication, even if its link versions are not - * compatible with us; - * - include IPv4 link specifier, if the primary address is not IPv4, log a - * BUG() warning, and return an empty smartlist; - * - include IPv6 link specifier if present in the node. */ -static void -get_lspecs_from_node(const node_t *node, smartlist_t *lspecs) -{ - link_specifier_t *ls; - tor_addr_port_t ap; - - tor_assert(node); - tor_assert(lspecs); - - /* Get the relay's IPv4 address. */ - node_get_prim_orport(node, &ap); - - /* We expect the node's primary address to be a valid IPv4 address. - * This conforms to the protocol, which requires either an IPv4 or IPv6 - * address (or both). */ - if (BUG(!tor_addr_is_v4(&ap.addr)) || - BUG(!tor_addr_port_is_valid_ap(&ap, 0))) { - return; - } - - ls = link_specifier_new(); - link_specifier_set_ls_type(ls, LS_IPV4); - link_specifier_set_un_ipv4_addr(ls, tor_addr_to_ipv4h(&ap.addr)); - link_specifier_set_un_ipv4_port(ls, ap.port); - /* Four bytes IPv4 and two bytes port. */ - link_specifier_set_ls_len(ls, sizeof(ap.addr.addr.in_addr) + - sizeof(ap.port)); - smartlist_add(lspecs, ls); - - /* Legacy ID is mandatory and will always be present in node. */ - ls = link_specifier_new(); - link_specifier_set_ls_type(ls, LS_LEGACY_ID); - memcpy(link_specifier_getarray_un_legacy_id(ls), node->identity, - link_specifier_getlen_un_legacy_id(ls)); - link_specifier_set_ls_len(ls, link_specifier_getlen_un_legacy_id(ls)); - smartlist_add(lspecs, ls); - - /* ed25519 ID is only included if the node has it, and the node declares a - protocol version that supports ed25519 link authentication, even if that - link version is not compatible with us. (We are sending the ed25519 key - to another tor, which may support different link versions.) */ - if (!ed25519_public_key_is_zero(&node->ed25519_id) && - node_supports_ed25519_link_authentication(node, 0)) { - ls = link_specifier_new(); - link_specifier_set_ls_type(ls, LS_ED25519_ID); - memcpy(link_specifier_getarray_un_ed25519_id(ls), &node->ed25519_id, - link_specifier_getlen_un_ed25519_id(ls)); - link_specifier_set_ls_len(ls, link_specifier_getlen_un_ed25519_id(ls)); - smartlist_add(lspecs, ls); - } - - /* Check for IPv6. If so, include it as well. */ - if (node_has_ipv6_orport(node)) { - ls = link_specifier_new(); - node_get_pref_ipv6_orport(node, &ap); - link_specifier_set_ls_type(ls, LS_IPV6); - size_t addr_len = link_specifier_getlen_un_ipv6_addr(ls); - const uint8_t *in6_addr = tor_addr_to_in6_addr8(&ap.addr); - uint8_t *ipv6_array = link_specifier_getarray_un_ipv6_addr(ls); - memcpy(ipv6_array, in6_addr, addr_len); - link_specifier_set_un_ipv6_port(ls, ap.port); - /* Sixteen bytes IPv6 and two bytes port. */ - link_specifier_set_ls_len(ls, addr_len + sizeof(ap.port)); - smartlist_add(lspecs, ls); - } -} - /* Using the given descriptor intro point ip, the node of the * rendezvous point rp_node and the service's subcredential, populate the * already allocated intro1_data object with the needed key material and link @@ -662,10 +587,9 @@ setup_introduce1_data(const hs_desc_intro_point_t *ip, tor_assert(subcredential); tor_assert(intro1_data); - /* Build the link specifiers from the extend information of the rendezvous - * circuit that we've picked previously. */ - rp_lspecs = smartlist_new(); - get_lspecs_from_node(rp_node, rp_lspecs); + /* Build the link specifiers from the node at the end of the rendezvous + * circuit that we opened for this introduction. */ + rp_lspecs = node_get_link_specifier_smartlist(rp_node, 0); if (smartlist_len(rp_lspecs) == 0) { /* We can't rendezvous without link specifiers. */ smartlist_free(rp_lspecs); @@ -1044,9 +968,7 @@ hs_circ_handle_introduce2(const hs_service_t *service, ret = 0; done: - SMARTLIST_FOREACH(data.link_specifiers, link_specifier_t *, lspec, - link_specifier_free(lspec)); - smartlist_free(data.link_specifiers); + link_specifier_smartlist_free(data.link_specifiers); memwipe(&data, 0, sizeof(data)); return ret; } diff --git a/src/feature/nodelist/nodelist.c b/src/feature/nodelist/nodelist.c index 9a2770180..32ee2677b 100644 --- a/src/feature/nodelist/nodelist.c +++ b/src/feature/nodelist/nodelist.c @@ -1189,6 +1189,102 @@ node_get_rsa_id_digest(const node_t *node) return (const uint8_t*)node->identity; } +/* Returns a new smartlist with all possible link specifiers from node: + * - legacy ID is mandatory thus MUST be present in node; + * - include ed25519 link specifier if present in the node, and the node + * supports ed25519 link authentication, and: + * - if direct_conn is true, its link versions are compatible with us, + * - if direct_conn is false, regardless of its link versions; + * - include IPv4 link specifier, if the primary address is not IPv4, log a + * BUG() warning, and return an empty smartlist; + * - include IPv6 link specifier if present in the node. + * + * If node is NULL, returns an empty smartlist. + * + * The smartlist must be freed using link_specifier_smartlist_free(). */ +smartlist_t * +node_get_link_specifier_smartlist(const node_t *node, bool direct_conn) +{ + link_specifier_t *ls; + tor_addr_port_t ap; + smartlist_t *lspecs = smartlist_new(); + + if (!node) + return lspecs; + + /* Get the relay's IPv4 address. */ + node_get_prim_orport(node, &ap); + + /* We expect the node's primary address to be a valid IPv4 address. + * This conforms to the protocol, which requires either an IPv4 or IPv6 + * address (or both). */ + if (BUG(!tor_addr_is_v4(&ap.addr)) || + BUG(!tor_addr_port_is_valid_ap(&ap, 0))) { + return lspecs; + } + + ls = link_specifier_new(); + link_specifier_set_ls_type(ls, LS_IPV4); + link_specifier_set_un_ipv4_addr(ls, tor_addr_to_ipv4h(&ap.addr)); + link_specifier_set_un_ipv4_port(ls, ap.port); + /* Four bytes IPv4 and two bytes port. */ + link_specifier_set_ls_len(ls, sizeof(ap.addr.addr.in_addr) + + sizeof(ap.port)); + smartlist_add(lspecs, ls); + + /* Legacy ID is mandatory and will always be present in node. */ + ls = link_specifier_new(); + link_specifier_set_ls_type(ls, LS_LEGACY_ID); + memcpy(link_specifier_getarray_un_legacy_id(ls), node->identity, + link_specifier_getlen_un_legacy_id(ls)); + link_specifier_set_ls_len(ls, link_specifier_getlen_un_legacy_id(ls)); + smartlist_add(lspecs, ls); + + /* ed25519 ID is only included if the node has it, and the node declares a + protocol version that supports ed25519 link authentication. + If direct_conn is true, we also require that the node's link version is + compatible with us. (Otherwise, we will be sending the ed25519 key + to another tor, which may support different link versions.) */ + if (!ed25519_public_key_is_zero(&node->ed25519_id) && + node_supports_ed25519_link_authentication(node, direct_conn)) { + ls = link_specifier_new(); + link_specifier_set_ls_type(ls, LS_ED25519_ID); + memcpy(link_specifier_getarray_un_ed25519_id(ls), &node->ed25519_id, + link_specifier_getlen_un_ed25519_id(ls)); + link_specifier_set_ls_len(ls, link_specifier_getlen_un_ed25519_id(ls)); + smartlist_add(lspecs, ls); + } + + /* Check for IPv6. If so, include it as well. */ + if (node_has_ipv6_orport(node)) { + ls = link_specifier_new(); + node_get_pref_ipv6_orport(node, &ap); + link_specifier_set_ls_type(ls, LS_IPV6); + size_t addr_len = link_specifier_getlen_un_ipv6_addr(ls); + const uint8_t *in6_addr = tor_addr_to_in6_addr8(&ap.addr); + uint8_t *ipv6_array = link_specifier_getarray_un_ipv6_addr(ls); + memcpy(ipv6_array, in6_addr, addr_len); + link_specifier_set_un_ipv6_port(ls, ap.port); + /* Sixteen bytes IPv6 and two bytes port. */ + link_specifier_set_ls_len(ls, addr_len + sizeof(ap.port)); + smartlist_add(lspecs, ls); + } + + return lspecs; +} + +/* Free a link specifier list. */ +void +link_specifier_smartlist_free_(smartlist_t *ls_list) +{ + if (!ls_list) + return; + + SMARTLIST_FOREACH(ls_list, link_specifier_t *, lspec, + link_specifier_free(lspec)); + smartlist_free(ls_list); +} + /** Return the nickname of <b>node</b>, or NULL if we can't find one. */ const char * node_get_nickname(const node_t *node) diff --git a/src/feature/nodelist/nodelist.h b/src/feature/nodelist/nodelist.h index 342095961..a3d65347a 100644 --- a/src/feature/nodelist/nodelist.h +++ b/src/feature/nodelist/nodelist.h @@ -77,6 +77,11 @@ int node_supports_v3_hsdir(const node_t *node); int node_supports_ed25519_hs_intro(const node_t *node); int node_supports_v3_rendezvous_point(const node_t *node); const uint8_t *node_get_rsa_id_digest(const node_t *node); +smartlist_t *node_get_link_specifier_smartlist(const node_t *node, + bool direct_conn); +void link_specifier_smartlist_free_(smartlist_t *ls_list); +#define link_specifier_smartlist_free(ls_list) \ + FREE_AND_NULL(smartlist_t, link_specifier_smartlist_free_, (ls_list)) int node_has_ipv6_addr(const node_t *node); int node_has_ipv6_orport(const node_t *node);