1 files changed, 124 insertions, 0 deletions
diff --git a/modules/pcp/listener.c b/modules/pcp/listener.c
new file mode 100644
index 0000000..7747672
--- /dev/null
+++ b/modules/pcp/listener.c
@@ -0,0 +1,124 @@
+/**
+ * @file listener.c Port Control Protocol module -- multicast listener
+ *
+ * Copyright (C) 2010 - 2016 Creytiv.com
+ */
+
+#include <re.h>
+#include <rew.h>
+#include <baresip.h>
+#include "pcp.h"
+
+
+/*
+ * Listen for incoming notifications on unicast/multicast port 5350
+ */
+
+
+struct pcp_listener {
+	struct udp_sock *us;
+	struct sa srv;
+	struct sa group;
+	pcp_msg_h *msgh;
+	void *arg;
+};
+
+
+static void destructor(void *arg)
+{
+	struct pcp_listener *pl = arg;
+
+	if (sa_isset(&pl->group, SA_ADDR))
+		(void)udp_multicast_leave(pl->us, &pl->group);
+
+	mem_deref(pl->us);
+}
+
+
+static void udp_recv(const struct sa *src, struct mbuf *mb, void *arg)
+{
+	struct pcp_listener *pl = arg;
+	struct pcp_msg *msg;
+	int err;
+
+#if 0
+	if (!sa_cmp(src, &pl->srv, SA_ADDR)) {
+		debug("pcp: listener: ignore %zu bytes from non-server %J\n",
+		      mb->end, src);
+		return;
+	}
+#endif
+
+	err = pcp_msg_decode(&msg, mb);
+	if (err)
+		return;
+
+	/* Validate PCP request */
+	if (!msg->hdr.resp) {
+		info("pcp: listener: ignore request from %J\n", src);
+		goto out;
+	}
+
+	if (pl->msgh)
+		pl->msgh(msg, pl->arg);
+
+ out:
+	mem_deref(msg);
+}
+
+
+int pcp_listen(struct pcp_listener **plp, const struct sa *srv,
+	       pcp_msg_h *msgh, void *arg)
+{
+	struct pcp_listener *pl;
+	struct sa laddr;
+	int err;
+
+	if (!plp || !srv || !msgh)
+		return EINVAL;
+
+	pl = mem_zalloc(sizeof(*pl), destructor);
+	if (!pl)
+		return ENOMEM;
+
+	pl->srv  = *srv;
+	pl->msgh = msgh;
+	pl->arg  = arg;
+
+	/* note: must listen on ANY to get multicast working */
+	sa_init(&laddr, sa_af(srv));
+	sa_set_port(&laddr, PCP_PORT_CLI);
+
+	err = udp_listen(&pl->us, &laddr, udp_recv, pl);
+	if (err)
+		goto out;
+
+	switch (sa_af(&laddr)) {
+
+	case AF_INET:
+		err = sa_set_str(&pl->group, "224.0.0.1", 0);
+		break;
+
+	case AF_INET6:
+		err = sa_set_str(&pl->group, "ff02::1", 0);
+		break;
+
+	default:
+		err = EAFNOSUPPORT;
+		break;
+	}
+	if (err)
+		goto out;
+
+	err = udp_multicast_join(pl->us, &pl->group);
+	if (err)
+		goto out;
+
+ out:
+	if (err)
+		mem_deref(pl);
+	else
+		*plp = pl;
+
+	return err;
+}