2 files changed, 95 insertions, 0 deletions
diff --git a/contrib/nat/test_regexp.c b/contrib/nat/test_regexp.c
new file mode 100644
index 000000000..808a703ca
--- /dev/null
+++ b/contrib/nat/test_regexp.c
@@ -0,0 +1,30 @@
+/* make test_regexp */
+#include <sys/types.h>
+#include <regex.h>
+#include <stdio.h>
+
+
+int main(int argc, char **argv)
+{
+	regex_t reg;
+	regmatch_t matches[2];
+
+	if (argc != 4) {
+		printf("Invoke with: test_regexp REGEXP REPLACE NR\n");
+		return -1;
+	}
+
+	if (regcomp(&reg, argv[1], REG_EXTENDED) != 0) {
+		fprintf(stderr, "Regexp '%s' is not valid.\n", argv[1]);
+		return -1;
+	}
+
+	if (regexec(&reg, argv[3], 2, matches, 0) == 0 && matches[1].rm_eo != -1)
+		printf("New Number: %s%s\n", argv[2], &argv[3][matches[1].rm_so]);
+	else
+		printf("No match.\n");
+
+	regfree(&reg);
+
+	return 0;
+}
diff --git a/contrib/nat/ussd_example.py b/contrib/nat/ussd_example.py
new file mode 100644
index 000000000..8f7a58d3f
--- /dev/null
+++ b/contrib/nat/ussd_example.py
@@ -0,0 +1,65 @@
+#!/usr/bin/env python2.7
+
+"""
+AGPLv3+ 2016 Copyright Holger Hans Peter Freyther
+
+Example of how to connect to the USSD side-channel and how to respond
+with a fixed message.
+"""
+
+import socket
+import struct
+
+ussdSocket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+ussdSocket.connect(('127.0.0.1', 5001))
+
+def send_dt1(dstref, data):
+    dlen = struct.pack('B', len(data)).encode('hex')
+    hex = '06' + dstref.encode('hex') + '00' + '01' + dlen + data.encode('hex')
+    pdata = hex.decode('hex')
+    out = struct.pack('>HB', len(pdata), 0xfd) + pdata
+    ussdSocket.send(out)
+
+def send_rel(srcref, dstref):
+    hex = '04' + dstref.encode('hex') + srcref.encode('hex') + '000100'
+    pdata = hex.decode('hex')
+    out = struct.pack('>HB', len(pdata), 0xfd) + pdata
+    ussdSocket.send(out)
+
+def recv_one():
+    plen = ussdSocket.recv(3)
+    (plen,ptype) = struct.unpack(">HB", plen)
+    data = ussdSocket.recv(plen)
+
+    return ptype, data
+
+# Assume this is the ID request
+data = ussdSocket.recv(4)
+ussdSocket.send("\x00\x08\xfe\x05\x00" + "\x05\x01" + "ussd")
+#                      ^len                ^len of tag ... and ignore
+
+# Expect a fake message. see struct ipac_msgt_sccp_state
+ptype, data = recv_one()
+print("%d %s" % (ptype, data.encode('hex')))
+(srcref, dstref, transid, invokeid) = struct.unpack("<3s3sBB", data[1:9])
+print("New transID %d invoke %d" % (transid, invokeid))
+
+# Expect a the invocation.. todo.. extract invoke id
+ptype, data = recv_one()
+print("%d %s" % (ptype, data.encode('hex')))
+
+# Reply with BSSAP + GSM 04.08 + MAP portion
+#                                    00 == invoke id     0f == DCS
+res = "01002a9b2a0802e1901c22a220020100301b02013b301604010f041155e7d2f9bc3a41412894991c06a9c9a713"
+send_dt1(dstref, res.decode('hex'))
+
+clear = "000420040109"
+send_dt1(dstref, clear.decode('hex'))
+
+# should be the clear complete
+send_rel(srcref, dstref)
+
+# Give it some time to handle connection shutdown properly
+print("Gracefully sleeping")
+import time
+time.sleep(3)