4 files changed, 34 insertions, 13 deletions

diff --git a/conf.c b/conf.c
index 6bd9717..02a4b65 100644
--- a/conf.c
+++ b/conf.c
@@ -235,6 +235,12 @@ static void conf_ports(const struct ctx *c, char optname, const char *optarg,
 		if (c->mode != MODE_PASTA)
 			die("'auto' port forwarding is only allowed for pasta");
 
+		if ((optname == 'T' || optname == 'U') && c->no_bindtodevice) {
+			warn(
+"'-%c auto' enabled without unprivileged SO_BINDTODEVICE", optname);
+			warn(
+"Forwarding from addresses other than 127.0.0.1 will not work");
+		}
 		fwd->mode = FWD_AUTO;
 		return;
 	}
diff --git a/pif.c b/pif.c
index 85904f3..db447b4 100644
--- a/pif.c
+++ b/pif.c
@@ -81,12 +81,6 @@ int pif_sock_l4(const struct ctx *c, enum epoll_type type, uint8_t pif,
 
 	ASSERT(pif_is_socket(pif));
 
-	if (pif == PIF_SPLICE) {
-		/* Sanity checks */
-		ASSERT(!ifname);
-		ASSERT(addr && inany_is_loopback(addr));
-	}
-
 	if (!addr) {
 		ref.fd = sock_l4_dualstack(c, type, port, ifname);
 	} else {
diff --git a/tcp.c b/tcp.c
index 06b7a1b..c844da7 100644
--- a/tcp.c
+++ b/tcp.c
@@ -2653,6 +2653,11 @@ static void tcp_ns_sock_init(const struct ctx *c, in_port_t port)
 {
 	ASSERT(!c->no_tcp);
 
+	if (!c->no_bindtodevice) {
+		tcp_sock_init(c, PIF_SPLICE, NULL, "lo", port);
+		return;
+	}
+
 	if (c->ifi4)
 		tcp_sock_init_one(c, PIF_SPLICE, &inany_loopback4, NULL, port);
 	if (c->ifi6)
diff --git a/udp.c b/udp.c
index 3d097fb..4b625b7 100644
--- a/udp.c
+++ b/udp.c
@@ -1183,6 +1183,26 @@ static void udp_splice_iov_init(void)
 }
 
 /**
+ * udp_ns_sock_init() - Init socket to listen for spliced outbound connections
+ * @c:		Execution context
+ * @port:	Port, host order
+ */
+static void udp_ns_sock_init(const struct ctx *c, in_port_t port)
+{
+	ASSERT(!c->no_udp);
+
+	if (!c->no_bindtodevice) {
+		udp_sock_init(c, PIF_SPLICE, NULL, "lo", port);
+		return;
+	}
+
+	if (c->ifi4)
+		udp_sock_init(c, PIF_SPLICE, &inany_loopback4, NULL, port);
+	if (c->ifi6)
+		udp_sock_init(c, PIF_SPLICE, &inany_loopback6, NULL, port);
+}
+
+/**
  * udp_port_rebind() - Rebind ports to match forward maps
  * @c:		Execution context
  * @outbound:	True to remap outbound forwards, otherwise inbound
@@ -1213,14 +1233,10 @@ static void udp_port_rebind(struct ctx *c, bool outbound)
 
 		if ((c->ifi4 && socks[V4][port] == -1) ||
 		    (c->ifi6 && socks[V6][port] == -1)) {
-			if (outbound) {
-				udp_sock_init(c, PIF_SPLICE,
-					      &inany_loopback4, NULL, port);
-				udp_sock_init(c, PIF_SPLICE,
-					      &inany_loopback6, NULL, port);
-			} else {
+			if (outbound)
+				udp_ns_sock_init(c, port);
+			else
 				udp_sock_init(c, PIF_HOST, NULL, NULL, port);
-			}
 		}
 	}
 }