nat: Add a test case for the connection tracking

This test case tests connectiont tracking by sending
a CR, getting a CC, sending a DTAP, receiving a DTAP,
receiving a RLSD, sending a RLC. It verifies that the
messages are properly patched specially the references
at the BSC.
diff --git a/openbsc/tests/bsc-nat/bsc_data.c b/openbsc/tests/bsc-nat/bsc_data.c
new file mode 100644
index 0000000..b31bf22
--- /dev/null
+++ b/openbsc/tests/bsc-nat/bsc_data.c
@@ -0,0 +1,72 @@
+/* test data */
+
+/* BSC -> MSC, CR */
+static const u_int8_t bsc_cr[] = {
+0x00, 0x2e, 0xfd,
+0x01, 0x00, 0x00, 0x15, 0x02, 0x02, 0x04, 0x02,
+0x42, 0xfe, 0x0f, 0x21, 0x00, 0x1f, 0x57, 0x05,
+0x08, 0x00, 0x72, 0xf4, 0x80, 0x20, 0x1c, 0xc3,
+0x51, 0x17, 0x12, 0x05, 0x08, 0x20, 0x72, 0xf4,
+0x90, 0x20, 0x1d, 0x50, 0x08, 0x29, 0x47, 0x80,
+0x00, 0x00, 0x00, 0x00, 0x80, 0x00 };
+
+static const u_int8_t bsc_cr_patched[] = {
+0x00, 0x2e, 0xfd,
+0x01, 0x00, 0x00, 0x05, 0x02, 0x02, 0x04, 0x02,
+0x42, 0xfe, 0x0f, 0x21, 0x00, 0x1f, 0x57, 0x05,
+0x08, 0x00, 0x72, 0xf4, 0x80, 0x20, 0x1c, 0xc3,
+0x51, 0x17, 0x12, 0x05, 0x08, 0x20, 0x72, 0xf4,
+0x90, 0x20, 0x1d, 0x50, 0x08, 0x29, 0x47, 0x80,
+0x00, 0x00, 0x00, 0x00, 0x80, 0x00 };
+
+/* CC, MSC -> BSC */
+static const u_int8_t msc_cc[] = {
+0x00, 0x0a, 0xfd,
+0x02, 0x00, 0x00, 0x05, 0x01, 0x1f, 0xe4, 0x02,
+0x01, 0x00 };
+static const u_int8_t msc_cc_patched[] = {
+0x00, 0x0a, 0xfd,
+0x02, 0x00, 0x00, 0x15, 0x01, 0x1f, 0xe4, 0x02,
+0x01, 0x00 };
+
+/* Classmark, BSC -> MSC */
+static const u_int8_t bsc_dtap[] = {
+0x00, 0x17, 0xfd,
+0x06, 0x01, 0x1f, 0xe4, 0x00, 0x01, 0x10, 0x00,
+0x0e, 0x54, 0x12, 0x03, 0x50, 0x18, 0x93, 0x13,
+0x06, 0x60, 0x14, 0x45, 0x00, 0x81, 0x00 };
+
+static const u_int8_t bsc_dtap_patched[] = {
+0x00, 0x17, 0xfd,
+0x06, 0x01, 0x1f, 0xe4, 0x00, 0x01, 0x10, 0x00,
+0x0e, 0x54, 0x12, 0x03, 0x50, 0x18, 0x93, 0x13,
+0x06, 0x60, 0x14, 0x45, 0x00, 0x81, 0x00 };
+
+/* Clear command, MSC -> BSC */
+static const u_int8_t msc_dtap[] = {
+0x00, 0x0d, 0xfd,
+0x06, 0x00, 0x00, 0x05, 0x00, 0x01, 0x06, 0x00,
+0x04, 0x20, 0x04, 0x01, 0x09 };
+static const u_int8_t msc_dtap_patched[] = {
+0x00, 0x0d, 0xfd,
+0x06, 0x00, 0x00, 0x15, 0x00, 0x01, 0x06, 0x00,
+0x04, 0x20, 0x04, 0x01, 0x09 };
+
+/*RLSD, MSC -> BSC */
+static const u_int8_t msc_rlsd[] = {
+0x00, 0x0a, 0xfd,
+0x04, 0x00, 0x00, 0x05, 0x01, 0x1f, 0xe4, 0x00,
+0x01, 0x00 };
+static const u_int8_t msc_rlsd_patched[] = {
+0x00, 0x0a, 0xfd,
+0x04, 0x00, 0x00, 0x15, 0x01, 0x1f, 0xe4, 0x00,
+0x01, 0x00 };
+
+/* RLC, BSC -> MSC */
+static const u_int8_t bsc_rlc[] = {
+0x00, 0x07, 0xfd,
+0x05, 0x01, 0x1f, 0xe4, 0x00, 0x00, 0x15 };
+
+static const u_int8_t bsc_rlc_patched[] = {
+0x00, 0x07, 0xfd,
+0x05, 0x01, 0x1f, 0xe4, 0x00, 0x00, 0x05 };