trap-manager: Don't require that remote is resolvable during installation

Initiation might later fail, of course, but we don't really
require an IP address when installing, that is, unless the remote
traffic selector is dynamic. As that would result in installing a
0.0.0.0/0 remote TS which is not ideal when a single IP is expected as
remote.

1 files changed, 49 insertions, 10 deletions

diff --git a/src/libcharon/sa/trap_manager.c b/src/libcharon/sa/trap_manager.c
index f9fee5e7e..6436a2549 100644
--- a/src/libcharon/sa/trap_manager.c
+++ b/src/libcharon/sa/trap_manager.c
@@ -158,6 +158,31 @@ CALLBACK(acquire_by_dst, bool,
 	return this->dst && this->dst->ip_equals(this->dst, dst);
 }
 
+/**
+ * Check if any remote TS are dynamic
+ */
+static bool dynamic_remote_ts(child_cfg_t *child)
+{
+	enumerator_t *enumerator;
+	linked_list_t *other_ts;
+	traffic_selector_t *ts;
+	bool found = FALSE;
+
+	other_ts = child->get_traffic_selectors(child, FALSE, NULL, NULL);
+	enumerator = other_ts->create_enumerator(other_ts);
+	while (enumerator->enumerate(enumerator, &ts))
+	{
+		if (ts->is_dynamic(ts))
+		{
+			found = TRUE;
+			break;
+		}
+	}
+	enumerator->destroy(enumerator);
+	other_ts->destroy_offset(other_ts, offsetof(traffic_selector_t, destroy));
+	return found;
+}
+
 METHOD(trap_manager_t, install, uint32_t,
 	private_trap_manager_t *this, peer_cfg_t *peer, child_cfg_t *child,
 	uint32_t reqid)
@@ -184,25 +209,39 @@ METHOD(trap_manager_t, install, uint32_t,
 		me = host_create_any(other->get_family(other));
 		wildcard = TRUE;
 	}
-	else if (!other || other->is_anyaddr(other))
+	else if (other && other->is_anyaddr(other))
 	{
-		DESTROY_IF(other);
+		other->destroy(other);
 		DBG1(DBG_CFG, "installing trap failed, remote address unknown");
 		return 0;
 	}
 	else
-	{
-		me = ike_cfg->resolve_me(ike_cfg, other->get_family(other));
-		if (!me || me->is_anyaddr(me))
+	{	/* depending on the traffic selectors we don't really need a remote
+		 * host yet, but we might fail later if no IP can be resolved */
+		if (!other && dynamic_remote_ts(child))
+		{	/* with dynamic TS we do need a host, otherwise 0.0.0.0/0 is used,
+			 * which is probably not what users expect*/
+			DBG1(DBG_CFG, "installing trap failed, remote address unknown with "
+				 "dynamic traffic selector");
+			return 0;
+		}
+		me = ike_cfg->resolve_me(ike_cfg, other ? other->get_family(other)
+												: AF_UNSPEC);
+		if (!other)
+		{
+			other = host_create_any(me ? me->get_family(me) : AF_INET);
+		}
+		other->set_port(other, ike_cfg->get_other_port(ike_cfg));
+		if ((!me || me->is_anyaddr(me)) && !other->is_anyaddr(other))
 		{
 			DESTROY_IF(me);
 			me = charon->kernel->get_source_addr(charon->kernel, other, NULL);
-			if (!me)
-			{
-				me = host_create_any(other->get_family(other));
-			}
-			me->set_port(me, ike_cfg->get_my_port(ike_cfg));
 		}
+		if (!me)
+		{
+			me = host_create_any(other->get_family(other));
+		}
+		me->set_port(me, ike_cfg->get_my_port(ike_cfg));
 	}
 
 	this->lock->write_lock(this->lock);