From f67945f0047d62ca546afbd74def30adfc9e2f89 Mon Sep 17 00:00:00 2001 From: Holger Hans Peter Freyther Date: Fri, 9 Oct 2009 07:08:11 +0200 Subject: [mgcp] Add a simple mgcp gateway used for the BSC The python script is a simple call-agent driving the client. Currently it is sending a AuditEndpoint message and is printing the result. The bsc_mgcp.c is a standalone process that will implement a MGCP Gateway for the MSC. On call handling the Call-Agent will ask the Gateway to "CreateConnection" and then this gateway needs to communicate with OpenBSC. Currently CreateConnection,ModifiyConnection,DeleteConnection and Endpoint auditing is implemented. [mgcp] Send RSIP on start and on first receive of any message Ignore the first request and send a RSIP. We do that because we might tunnel UDP through some other things and have no direct way to connect to the call-agent. Also the transaction is not checked and we ignore the response from the call-agent, actually we print the '200 ' or any other value as unhandled... [mgcp] Print the MGCP command next to the response code This allows to see which commands were sent by the server mgcp: Terminate it with a new line [mgcp] Make number of endpoints static... For now this is fixed to the number of endpoints as of the GSM specification... [mgcp] The endpoint names seem to be base 16... use strtoul to parse Use strtoul to parse the base 16 number from the mgw string. [mgcp] Log the endpoints as hex numbers... [mgcp] Only send the RSIP on the first incoming message.. Remove call_agent option (also remove the number from the getopt call). [mgcp] Start couting at 1 for the mgcp [mgcp] Slight attempt to improve the grammar of the strings [mgcp] Share validation routines between DLCX and MDCX [mgcp] Remove help for dead config options [mgcp] Specify a different IN addr in the SDP records In case of NAT traversal be able to listen on a given interface (like 127.0.0.1) but claim to receive data at the beginning of the tunnel. [mgcp] Fix the static copy of the SDP file WIP verify out factoring broken.. [mgcp] Introduce VTY to the mgcp for config file parsing... Parse the MGCP config file via the VTY framework. [mgcp] Handle SDP parameters through VTY.. Currently the payload type, name and rate can be specified in the config file. [mgcp] Add an option to bind all rtp ports early This can be useful for testing and in deployment to make sure no runtime resource limit can be hit. [mgcp] Add some API doc comment [mgcp] Convert the packets of the example server to ascii This will allow to easily patch the call id... to run the server in a loop and make it work with the mediagateway [mgcp] Assign CI_UNUSED... to be more obvious... [mgcp] Use DEBUG and not DEBUGPC and specially not printf Improve the logging a bit in the mgcp [mgcp] Change the fake server to change the call id This assume the call-agent will just increment the id as well.... this is true for our implementation [mgcp] Generate the transaction id dynamically.. This way wireshark will be more happy about it... [mgcp] Recognize responses from the network.. This is just recognizing the response code and then is doing nothing with it. Also change the script to generate response messages... [mgcp] Improve debug messages for CRCX/MDCX.. Log on which ports the media gateway is listening and where the other (server) gateway is located --- openbsc/contrib/mgcp_server.py | 54 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 54 insertions(+) create mode 100755 openbsc/contrib/mgcp_server.py (limited to 'openbsc/contrib') diff --git a/openbsc/contrib/mgcp_server.py b/openbsc/contrib/mgcp_server.py new file mode 100755 index 000000000..cf3ef3845 --- /dev/null +++ b/openbsc/contrib/mgcp_server.py @@ -0,0 +1,54 @@ +#!/usr/bin/env python +# Simple server for mgcp... send audit, receive response.. + +import socket, time + +MGCP_GATEWAY_PORT = 2427 +MGCP_CALLAGENT_PORT = 2727 + +rsip_resp = """200 321321332\r\n""" +audit_packet = """AUEP %d 13@mgw MGCP 1.0\r\n""" +crcx_packet = """CRCX %d 14@mgw MGCP 1.0\r\nC: 4a84ad5d25f\r\nL: p:20, a:GSM-EFR, nt:IN\r\nM: recvonly\r\n""" +dlcx_packet = """DLCX %d 14@mgw MGCP 1.0\r\nC: 4a84ad5d25f\r\nI: %d\r\n""" +mdcx_packet = """MDCX %d 14@mgw MGCP 1.0\r\nC: 4a84ad5d25f\r\nI: %d\r\nL: p:20, a:GSM-EFR, nt:IN\r\nM: recvonly\r\n\r\nv=0\r\no=- 258696477 0 IN IP4 172.16.1.107\r\ns=-\r\nc=IN IP4 172.16.1.107\r\nt=0 0\r\nm=audio 4400 RTP/AVP 127\r\na=rtpmap:127 GSM-EFR/8000/1\r\na=ptime:20\r\na=recvonly\r\nm=image 4402 udptl t38\r\na=T38FaxVersion:0\r\na=T38MaxBitRate:14400\r\n""" + +def hexdump(src, length=8): + """Recipe is from http://code.activestate.com/recipes/142812/""" + result = [] + digits = 4 if isinstance(src, unicode) else 2 + for i in xrange(0, len(src), length): + s = src[i:i+length] + hexa = b' '.join(["%0*X" % (digits, ord(x)) for x in s]) + text = b''.join([x if 0x20 <= ord(x) < 0x7F else b'.' for x in s]) + result.append( b"%04X %-*s %s" % (i, length*(digits + 1), hexa, text) ) + return b'\n'.join(result) + +server_socket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM) +server_socket.bind(("127.0.0.1", MGCP_CALLAGENT_PORT)) +server_socket.setblocking(0) + + +def send_receive(packet): + server_socket.sendto(packet, ("127.0.0.1", MGCP_GATEWAY_PORT)) + try: + data, addr = server_socket.recvfrom(4096) + print hexdump(data), addr + except socket.error: + pass + +def generate_tid(): + import random + return random.randint(0, 65123) + + + +i = 1 +while True: + send_receive(rsip_resp) + send_receive(audit_packet) + send_receive(crcx_packet % generate_tid() ) + send_receive(mdcx_packet % (generate_tid(), i)) + send_receive(dlcx_packet % (generate_tid(), i)) + i = i + 1 + + time.sleep(3) -- cgit v1.2.3