Merge branch 'pr_1930_squashed'

changes/ticket33816

@@ -0,0 +1,4 @@
+  o Code simplification and refactoring:
+    - When an extend cell is missing an IPv4 or IPv6 address, fill in the address
+      from the extend info. This is similar to what was done in ticket 33633 for
+      ed25519 keys. Closes ticket 33816. Patch by Neel Chauhan.

src/feature/relay/circuitbuild_relay.c

@@ -122,6 +122,52 @@ circuit_extend_add_ed25519_helper(struct extend_cell_t *ec)
   return 0;
 }
 
+/* Make sure the extend cell <b>ec</b> has an IPv4 address if the relay
+ * supports in, and if not, fill it in. */
+STATIC int
+circuit_extend_add_ipv4_helper(struct extend_cell_t *ec)
+{
+  IF_BUG_ONCE(!ec) {
+    return -1;
+  }
+
+  const node_t *node = node_get_by_id((const char *) ec->node_id);
+  if (node) {
+    tor_addr_port_t node_ipv4;
+    node_get_prim_orport(node, &node_ipv4);
+    if (tor_addr_is_null(&ec->orport_ipv4.addr) &&
+        !tor_addr_is_null(&node_ipv4.addr)) {
+      tor_addr_copy(&ec->orport_ipv4.addr, &node_ipv4.addr);
+      ec->orport_ipv4.port = node_ipv4.port;
+    }
+  }
+
+  return 0;
+}
+
+/* Make sure the extend cell <b>ec</b> has an IPv6 address if the relay
+ * supports in, and if not, fill it in. */
+STATIC int
+circuit_extend_add_ipv6_helper(struct extend_cell_t *ec)
+{
+  IF_BUG_ONCE(!ec) {
+    return -1;
+  }
+
+  const node_t *node = node_get_by_id((const char *) ec->node_id);
+  if (node) {
+    tor_addr_port_t node_ipv6;
+    node_get_pref_ipv6_orport(node, &node_ipv6);
+    if (tor_addr_is_null(&ec->orport_ipv6.addr) &&
+        !tor_addr_is_null(&node_ipv6.addr)) {
+      tor_addr_copy(&ec->orport_ipv6.addr, &node_ipv6.addr);
+      ec->orport_ipv6.port = node_ipv6.port;
+    }
+  }
+
+  return 0;
+}
+
 /* Check if the address and port in the tor_addr_port_t <b>ap</b> are valid,
  * and are allowed by the current ExtendAllowPrivateAddresses config.
  *
@@ -412,6 +458,12 @@ circuit_extend(struct cell_t *cell, struct circuit_t *circ)
   if (circuit_extend_lspec_valid_helper(&ec, circ) < 0)
     return -1;
 
+  if (circuit_extend_add_ipv4_helper(&ec) < 0)
+    return -1;
+
+  if (circuit_extend_add_ipv6_helper(&ec) < 0)
+    return -1;
+
   /* Check the addresses, without logging */
   const int ipv4_valid = circuit_extend_addr_port_is_valid(&ec.orport_ipv4,
                                                            false, false, 0);

src/feature/relay/circuitbuild_relay.h

@@ -73,6 +73,8 @@ onionskin_answer(struct or_circuit_t *circ,
 
 STATIC int circuit_extend_state_valid_helper(const struct circuit_t *circ);
 STATIC int circuit_extend_add_ed25519_helper(struct extend_cell_t *ec);
+STATIC int circuit_extend_add_ipv4_helper(struct extend_cell_t *ec);
+STATIC int circuit_extend_add_ipv6_helper(struct extend_cell_t *ec);
 STATIC int circuit_extend_lspec_valid_helper(const struct extend_cell_t *ec,
                                              const struct circuit_t *circ);
 STATIC const tor_addr_port_t * circuit_choose_ip_ap_for_extend(

src/test/test_circuitbuild.c

@@ -36,6 +36,7 @@
 #include "feature/relay/routermode.h"
 
 #include "feature/nodelist/node_st.h"
+#include "feature/nodelist/routerinfo_st.h"
 
 /* Dummy nodes smartlist for testing */
 static smartlist_t dummy_nodes;
@@ -823,6 +824,77 @@ test_circuit_extend_lspec_valid(void *arg)
   tor_free(p_chan);
 }
 
+#define NODE_SET_IPV4(node, ipv4_addr, ipv4_port) { \
+    tor_addr_t addr; \
+    tor_addr_parse(&addr, ipv4_addr); \
+    node->ri->addr = tor_addr_to_ipv4h(&addr); \
+    node->ri->or_port = ipv4_port; \
+  }
+
+#define NODE_CLEAR_IPV4(node) { \
+    node->ri->addr = 0; \
+    node->ri->or_port = 0; \
+  }
+
+#define NODE_SET_IPV6(node, ipv6_addr_str, ipv6_port) { \
+    tor_addr_parse(&node->ri->ipv6_addr, ipv6_addr_str); \
+    node->ri->ipv6_orport = ipv6_port; \
+  }
+
+/* Test the different cases in circuit_extend_add_ed25519_helper(). */
+static void
+test_circuit_extend_add_ip(void *arg)
+{
+  (void) arg;
+  tor_addr_t ipv4_tmp;
+  extend_cell_t *ec = tor_malloc_zero(sizeof(extend_cell_t));
+  extend_cell_t *old_ec = tor_malloc_zero(sizeof(extend_cell_t));
+
+  node_t *fake_node = tor_malloc_zero(sizeof(node_t));
+  routerinfo_t *ri = tor_malloc_zero(sizeof(routerinfo_t));
+
+  MOCK(node_get_by_id, mock_node_get_by_id);
+
+  /* Set up the fake variables for the IPv4 test */
+  fake_node->ri = ri;
+  mocked_node = fake_node;
+  memset(ec->node_id, 0xAA, sizeof(ec->node_id));
+  memcpy(old_ec, ec, sizeof(extend_cell_t));
+  NODE_SET_IPV4(fake_node, PUBLIC_IPV4, VALID_PORT);
+
+  /* Do the IPv4 test */
+  tt_int_op(circuit_extend_add_ipv4_helper(ec), OP_EQ, 0);
+  tor_addr_from_ipv4h(&ipv4_tmp, fake_node->ri->addr);
+  /* The IPv4 should match */
+  tt_int_op(tor_addr_compare(&ec->orport_ipv4.addr, &ipv4_tmp, CMP_SEMANTIC),
+            OP_EQ, 0);
+  tt_int_op(ec->orport_ipv4.port, OP_EQ, VALID_PORT);
+
+  /* Set up the fake variables for the IPv6 test */
+  memcpy(ec, old_ec, sizeof(extend_cell_t));
+  NODE_CLEAR_IPV4(fake_node);
+  NODE_SET_IPV6(fake_node, PUBLIC_IPV6, VALID_PORT);
+
+  /* Do the IPv6 test */
+  tt_int_op(circuit_extend_add_ipv6_helper(ec), OP_EQ, 0);
+  /* The IPv6 should match */
+  tt_int_op(tor_addr_compare(&ec->orport_ipv6.addr, &fake_node->ri->ipv6_addr,
+            CMP_SEMANTIC), OP_EQ, 0);
+  tt_int_op(ec->orport_ipv6.port, OP_EQ, VALID_PORT);
+
+  /* Cleanup */
+  mocked_node = NULL;
+
+ done:
+  UNMOCK(node_get_by_id);
+
+  tor_free(ec);
+  tor_free(old_ec);
+
+  tor_free(ri);
+  tor_free(fake_node);
+}
+
 static bool can_extend_over_ipv6_result = false;
 static int mock_router_can_extend_over_ipv6_calls = 0;
 static bool
@@ -1902,6 +1974,7 @@ struct testcase_t circuitbuild_tests[] = {
   TEST_CIRCUIT(extend_state_valid, TT_FORK),
   TEST_CIRCUIT(extend_add_ed25519, TT_FORK),
   TEST_CIRCUIT(extend_lspec_valid, TT_FORK),
+  TEST_CIRCUIT(extend_add_ip, TT_FORK),
   TEST_CIRCUIT(choose_ip_ap_for_extend, 0),
 
   TEST_CIRCUIT_PASSTHROUGH(open_connection_for_extend, TT_FORK, "4"),