ip_packet: Add function to easily encode UDP packets

2 files changed, 29 insertions, 0 deletions

diff --git a/src/libipsec/ip_packet.c b/src/libipsec/ip_packet.c
index 7de4658b9..f6e08c0cb 100644
--- a/src/libipsec/ip_packet.c
+++ b/src/libipsec/ip_packet.c
@@ -435,3 +435,21 @@ ip_packet_t *ip_packet_create_from_data(host_t *src, host_t *dst,
 			return NULL;
 	}
 }
+
+/**
+ * Described in header.
+ */
+ip_packet_t *ip_packet_create_udp_from_data(host_t *src, host_t *dst,
+											chunk_t data)
+{
+	struct udphdr udp = {
+		.len = htons(8 + data.len),
+		.check = 0,
+	};
+	ip_packet_t *packet;
+
+	data = chunk_cat("cc", chunk_from_thing(udp), data);
+	packet = ip_packet_create_from_data(src, dst, IPPROTO_UDP, data);
+	chunk_free(&data);
+	return packet;
+}
diff --git a/src/libipsec/ip_packet.h b/src/libipsec/ip_packet.h
index 73721cfd1..fa38eac2c 100644
--- a/src/libipsec/ip_packet.h
+++ b/src/libipsec/ip_packet.h
@@ -115,4 +115,15 @@ ip_packet_t *ip_packet_create(chunk_t packet);
 ip_packet_t *ip_packet_create_from_data(host_t *src, host_t *dst,
 										u_int8_t next_header, chunk_t data);
 
+/**
+ * Encode a UDP packet from the given data.
+ *
+ * @param src			source address and port (cloned)
+ * @param dst			destination address and port (cloned)
+ * @param data			UDP data (cloned)
+ * @return				ip_packet_t instance, or NULL if invalid
+ */
+ip_packet_t *ip_packet_create_udp_from_data(host_t *src, host_t *dst,
+											chunk_t data);
+
 #endif /** IP_PACKET_H_ @}*/