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.

1 files changed, 4 insertions, 82 deletions

diff --git a/src/feature/hs/hs_circuit.c b/src/feature/hs/hs_circuit.c
index e3873d2f18..253c24d643 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;
 }