Allow multiple addresses in extend_info_t.

In practice, there will be at most one ipv4 address and ipv6 address
for now, but this code is designed to not care which address is
which until forced to do so.

This patch does not yet actually create extend_info_t objects with
multiple addresses.

Closes #34069.

8 files changed, 77 insertions, 26 deletions

diff --git a/src/feature/client/bridges.c b/src/feature/client/bridges.c
index 66b04f3bc2..3a3d1bb681 100644
--- a/src/feature/client/bridges.c
+++ b/src/feature/client/bridges.c
@@ -259,12 +259,25 @@ addr_is_a_configured_bridge(const tor_addr_t *addr,
 /** If we have a bridge configured whose digest matches
  * <b>ei->identity_digest</b>, or a bridge with no known digest whose address
  * matches <b>ei->addr</b>:<b>ei->port</b>, return 1.  Else return 0.
- * If <b>ei->onion_key</b> is NULL, check for address/port matches only. */
+ * If <b>ei->onion_key</b> is NULL, check for address/port matches only.
+ *
+ * Note that if the extend_info_t contains multiple addresses, we return true
+ * only if _every_ address is a bridge.
+ */
 int
 extend_info_is_a_configured_bridge(const extend_info_t *ei)
 {
   const char *digest = ei->onion_key ? ei->identity_digest : NULL;
-  return addr_is_a_configured_bridge(&ei->addr, ei->port, digest);
+  const tor_addr_port_t *ap1 = NULL, *ap2 = NULL;
+  if (! tor_addr_is_null(&ei->orports[0].addr))
+    ap1 = &ei->orports[0];
+  if (! tor_addr_is_null(&ei->orports[1].addr))
+    ap2 = &ei->orports[1];
+  IF_BUG_ONCE(ap1 == NULL)
+    return 0;
+  return addr_is_a_configured_bridge(&ap1->addr, ap1->port, digest) &&
+    (ap2 == NULL ||
+     addr_is_a_configured_bridge(&ap2->addr, ap2->port, digest));
 }
 
 /** Wrapper around get_configured_bridge_by_addr_port_digest() to look
diff --git a/src/feature/nodelist/describe.c b/src/feature/nodelist/describe.c
index 00896d5a44..f118436499 100644
--- a/src/feature/nodelist/describe.c
+++ b/src/feature/nodelist/describe.c
@@ -12,6 +12,7 @@
 #define DESCRIBE_PRIVATE
 
 #include "core/or/or.h"
+#include "core/or/extendinfo.h"
 #include "feature/nodelist/describe.h"
 
 #include "core/or/extend_info_st.h"
@@ -208,11 +209,16 @@ extend_info_describe(const extend_info_t *ei)
   if (!ei)
     return "<null>";
 
+  const tor_addr_port_t *ap4 = extend_info_get_orport(ei, AF_INET);
+  const tor_addr_port_t *ap6 = extend_info_get_orport(ei, AF_INET6);
+  uint32_t addr4 = ap4 ? tor_addr_to_ipv4h(&ap4->addr) : 0;
+  const tor_addr_t *addr6 = ap6 ? &ap6->addr : NULL;
+
   return format_node_description(buf,
                                  ei->identity_digest,
                                  ei->nickname,
-                                 &ei->addr,
-                                 0);
+                                 addr6,
+                                 addr4);
 }
 
 /** Set <b>buf</b> (which must have MAX_VERBOSE_NICKNAME_LEN+1 bytes) to the
diff --git a/src/feature/nodelist/routerset.c b/src/feature/nodelist/routerset.c
index ebc08b7a51..cba7203d44 100644
--- a/src/feature/nodelist/routerset.c
+++ b/src/feature/nodelist/routerset.c
@@ -306,12 +306,19 @@ routerset_add_unknown_ccs(routerset_t **setp, int only_if_some_cc_set)
 int
 routerset_contains_extendinfo(const routerset_t *set, const extend_info_t *ei)
 {
-  return routerset_contains(set,
-                            &ei->addr,
-                            ei->port,
-                            ei->nickname,
-                            ei->identity_digest,
-                            -1 /*country*/);
+  const tor_addr_port_t *ap1 = NULL, *ap2 = NULL;
+  if (! tor_addr_is_null(&ei->orports[0].addr))
+    ap1 = &ei->orports[0];
+  if (! tor_addr_is_null(&ei->orports[1].addr))
+    ap2 = &ei->orports[1];
+  return routerset_contains2(set,
+                             ap1 ? &ap1->addr : NULL,
+                             ap1 ? ap1->port : 0,
+                             ap2 ? &ap2->addr : NULL,
+                             ap2 ? ap2->port : 0,
+                             ei->nickname,
+                             ei->identity_digest,
+                             -1 /*country*/);
 }
 
 /** Return true iff <b>ri</b> is in <b>set</b>.  If country is <b>-1</b>, we
diff --git a/src/feature/relay/selftest.c b/src/feature/relay/selftest.c
index c663eb26b2..77c04abdd7 100644
--- a/src/feature/relay/selftest.c
+++ b/src/feature/relay/selftest.c
@@ -256,14 +256,15 @@ router_do_orport_reachability_checks(const routerinfo_t *me,
    * be NULL. */
   if (ei) {
     const char *family_name = fmt_af_family(family);
+    const tor_addr_port_t *ap = extend_info_get_orport(ei, family);
     log_info(LD_CIRC, "Testing %s of my %s ORPort: %s.",
              !orport_reachable ? "reachability" : "bandwidth",
-             family_name, fmt_addrport(&ei->addr, ei->port));
+             family_name, fmt_addrport_ap(ap));
     if (!orport_reachable) {
       /* This is only a 'reachability test' if we don't already think that
        * the port is reachable.  If we _do_ think it's reachable, then
        * it counts as a 'bandwidth test'. */
-      inform_testing_reachability(&ei->addr, ei->port, false);
+      inform_testing_reachability(&ap->addr, ap->port, false);
     }
     circuit_launch_by_extend_info(CIRCUIT_PURPOSE_TESTING, ei,
                                   CIRCLAUNCH_NEED_CAPACITY|
diff --git a/src/feature/rend/rendclient.c b/src/feature/rend/rendclient.c
index 9c2286bbcf..e171562d17 100644
--- a/src/feature/rend/rendclient.c
+++ b/src/feature/rend/rendclient.c
@@ -235,9 +235,15 @@ rend_client_send_introduction(origin_circuit_t *introcirc,
     /* version 2 format */
     extend_info_t *extend_info = rendcirc->build_state->chosen_exit;
     int klen;
+    const tor_addr_port_t *orport =
+      extend_info_get_orport(extend_info, AF_INET);
+    IF_BUG_ONCE(! orport) {
+      /* we should never put an IPv6 address here. */
+      goto perm_err;
+    }
     /* nul pads */
-    set_uint32(tmp+v3_shift+1, tor_addr_to_ipv4n(&extend_info->addr));
-    set_uint16(tmp+v3_shift+5, htons(extend_info->port));
+    set_uint32(tmp+v3_shift+1, tor_addr_to_ipv4n(&orport->addr));
+    set_uint16(tmp+v3_shift+5, htons(orport->port));
     memcpy(tmp+v3_shift+7, extend_info->identity_digest, DIGEST_LEN);
     klen = crypto_pk_asn1_encode(extend_info->onion_key,
                                  tmp+v3_shift+7+DIGEST_LEN+2,
diff --git a/src/feature/rend/rendcommon.c b/src/feature/rend/rendcommon.c
index 07cbeaa2f7..775d487805 100644
--- a/src/feature/rend/rendcommon.c
+++ b/src/feature/rend/rendcommon.c
@@ -234,7 +234,12 @@ rend_encode_v2_intro_points(char **encoded, rend_service_descriptor_t *desc)
       goto done;
     }
     /* Assemble everything for this introduction point. */
-    address = tor_addr_to_str_dup(&info->addr);
+    const tor_addr_port_t *orport = extend_info_get_orport(info, AF_INET);
+    IF_BUG_ONCE(!orport) {
+      /* There must be an IPv4 address for v2 hs. */
+      goto done;
+    }
+    address = tor_addr_to_str_dup(&orport->addr);
     res = tor_snprintf(unenc + unenc_written, unenc_len - unenc_written,
                          "introduction-point %s\n"
                          "ip-address %s\n"
@@ -243,7 +248,7 @@ rend_encode_v2_intro_points(char **encoded, rend_service_descriptor_t *desc)
                          "service-key\n%s",
                        id_base32,
                        address,
-                       info->port,
+                       orport->port,
                        onion_key,
                        service_key);
     tor_free(address);
diff --git a/src/feature/rend/rendparse.c b/src/feature/rend/rendparse.c
index 0979d767a7..c28add5ca9 100644
--- a/src/feature/rend/rendparse.c
+++ b/src/feature/rend/rendparse.c
@@ -10,6 +10,7 @@
  **/
 
 #include "core/or/or.h"
+#include "core/or/extendinfo.h"
 #include "feature/dirparse/parsecommon.h"
 #include "feature/dirparse/sigcommon.h"
 #include "feature/rend/rendcommon.h"
@@ -428,7 +429,8 @@ rend_parse_introduction_points(rend_service_descriptor_t *parsed,
     }
     /* Allocate new intro point and extend info. */
     intro = tor_malloc_zero(sizeof(rend_intro_point_t));
-    info = intro->extend_info = tor_malloc_zero(sizeof(extend_info_t));
+    info = intro->extend_info =
+      extend_info_new(NULL, NULL, NULL, NULL, NULL, NULL, 0);
     /* Parse identifier. */
     tok = find_by_keyword(tokens, R_IPO_IDENTIFIER);
     if (base32_decode(info->identity_digest, DIGEST_LEN,
@@ -446,12 +448,13 @@ rend_parse_introduction_points(rend_service_descriptor_t *parsed,
                   info->identity_digest, DIGEST_LEN);
     /* Parse IP address. */
     tok = find_by_keyword(tokens, R_IPO_IP_ADDRESS);
-    if (tor_addr_parse(&info->addr, tok->args[0])<0) {
+    tor_addr_t addr;
+    if (tor_addr_parse(&addr, tok->args[0])<0) {
       log_warn(LD_REND, "Could not parse introduction point address.");
       rend_intro_point_free(intro);
       goto err;
     }
-    if (tor_addr_family(&info->addr) != AF_INET) {
+    if (tor_addr_family(&addr) != AF_INET) {
       log_warn(LD_REND, "Introduction point address was not ipv4.");
       rend_intro_point_free(intro);
       goto err;
@@ -459,14 +462,18 @@ rend_parse_introduction_points(rend_service_descriptor_t *parsed,
 
     /* Parse onion port. */
     tok = find_by_keyword(tokens, R_IPO_ONION_PORT);
-    info->port = (uint16_t) tor_parse_long(tok->args[0],10,1,65535,
+    uint16_t port = (uint16_t) tor_parse_long(tok->args[0],10,1,65535,
                                            &num_ok,NULL);
-    if (!info->port || !num_ok) {
+    if (!port || !num_ok) {
       log_warn(LD_REND, "Introduction point onion port %s is invalid",
                escaped(tok->args[0]));
       rend_intro_point_free(intro);
       goto err;
     }
+
+    /* Add the address and port. */
+    extend_info_add_orport(info, &addr, port);
+
     /* Parse onion key. */
     tok = find_by_keyword(tokens, R_IPO_ONION_KEY);
     if (!crypto_pk_public_exponent_ok(tok->key)) {
diff --git a/src/feature/rend/rendservice.c b/src/feature/rend/rendservice.c
index 8154840f12..1c456cb6ee 100644
--- a/src/feature/rend/rendservice.c
+++ b/src/feature/rend/rendservice.c
@@ -1832,8 +1832,11 @@ rend_service_use_direct_connection(const or_options_t* options,
   /* 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. */
+  const tor_addr_port_t *ap = extend_info_get_orport(ei, AF_INET);
+  if (!ap)
+    return 0;
   return (rend_service_allow_non_anonymous_connection(options) &&
-          fascist_firewall_allows_address_addr(&ei->addr, ei->port,
+          fascist_firewall_allows_address_addr(&ap->addr, ap->port,
                                                FIREWALL_OR_CONNECTION, 0, 0));
 }
 
@@ -2262,7 +2265,8 @@ find_rp_for_intro(const rend_intro_cell_t *intro,
   /* 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)) {
+  const tor_addr_port_t *orport = extend_info_get_orport(rp, AF_INET);
+  if (! orport || !extend_info_addr_is_allowed(&orport->addr)) {
     if (err_msg_out) {
       tor_asprintf(&err_msg,
                    "Relay IP in INTRODUCE2 cell is private address.");
@@ -2531,9 +2535,11 @@ rend_service_parse_intro_for_v2(
     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));
+  extend_info = extend_info_new(NULL, NULL, NULL, NULL, NULL, NULL, 0);
+  tor_addr_t addr;
+  tor_addr_from_ipv4n(&addr, get_uint32(buf + 1));
+  uint16_t port = ntohs(get_uint16(buf + 5));
+  extend_info_add_orport(extend_info, &addr, port);
   memcpy(extend_info->identity_digest, buf + 7, DIGEST_LEN);
   extend_info->nickname[0] = '$';
   base16_encode(extend_info->nickname + 1, sizeof(extend_info->nickname) - 1,