| #!/usr/bin/env python3 |
| # MIT License |
| # |
| # Copyright (c) 2021 by sysmocom - s.f.m.c. GmbH <info@sysmocom.de> |
| # Author: Pau Espin Pedrol <pespin@sysmocom.de> |
| # |
| # SPDX-License-Identifier: MIT |
| # |
| # Permission is hereby granted, free of charge, to any person obtaining a copy |
| # of this software and associated documentation files (the "Software"), to deal |
| # in the Software without restriction, including without limitation the rights |
| # to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
| # copies of the Software, and to permit persons to whom the Software is |
| # furnished to do so, subject to the following conditions: |
| # |
| # The above copyright notice and this permission notice (including the next |
| # paragraph) shall be included in all copies or substantial portions of the |
| # Software. |
| # |
| # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| # IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| # FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
| # AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| # LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE |
| # SOFTWARE. |
| |
| |
| import socket |
| import argparse |
| import struct |
| from ipaddress import ip_address, IPv4Address |
| |
| GTP1C_PORT = 2123 |
| BUF_SIZE = 4096 |
| |
| GTP_HDRv1_FLAG_PN = (1<<0) |
| GTP_HDRv1_FLAG_S = (1<<1) |
| GTP_HDRv1_FLAG_E = (1<<2) |
| GTP_HDRv1_PT_GTP = (1<<4) |
| GTP_HDRv1_VER_GTP1 = (1<<5) |
| |
| GTP_HDRv2_FLAG_T = (1<<3) |
| GTP_HDRv2_FLAG_P = (1<<4) |
| GTP_HDRv2_VER_GTP2 = (2<<5) |
| |
| def gen_gtpc_v1_hdr(flags, type, length, tei, seq=0, npdu=0, next=0): |
| spare = 0 |
| if (flags & (GTP_HDRv1_FLAG_PN|GTP_HDRv1_FLAG_S|GTP_HDRv1_FLAG_E)): |
| #long format |
| length += 4 |
| d = struct.pack('!BBHIHBB', flags, type, length, tei, seq, npdu, next) |
| else: |
| #short format |
| d = struct.pack('!BBHI', flags, type, length, tei) |
| return d |
| |
| def gen_gtpc_v2_hdr(flags, type, length, tei=0, seq=0): |
| spare = 0 |
| if (flags & (GTP_HDRv2_FLAG_T)): |
| #long format, with TEI |
| length += 4 + 4 |
| d = struct.pack('!BBHIHBB', flags, type, length, tei, seq >> 8, seq & 0xff, spare) |
| else: |
| #short format |
| length += 4 |
| d = struct.pack('!BBHHBB', flags, type, length, seq >> 8, seq & 0xff, spare) |
| return d |
| |
| def gen_gtpc_v1_echo_req(tei=0, append_flags=0, seq=0, npdu=0, next=0): |
| return gen_gtpc_v1_hdr(GTP_HDRv1_VER_GTP1 | GTP_HDRv1_PT_GTP | append_flags, 1, 0, tei, seq, npdu, next) |
| |
| def gen_gtpc_v2_echo_req(append_flags=0, seq=0, recovery=0, node_features=-1): |
| length = 0 |
| payload = b'' |
| if (recovery > 0): |
| recovery_ie = struct.pack('!BHBB', 3, 1, 0, recovery) |
| payload += recovery_ie |
| length += len(recovery_ie) |
| if (node_features > 0): |
| node_features_ie = struct.pack('!BHBB', 152, 1, 0, node_features) |
| payload += node_features_ie |
| length += len(node_features_ie) |
| return gen_gtpc_v2_hdr(GTP_HDRv2_VER_GTP2 | append_flags, 1, length, 0, seq) + payload |
| |
| def tx_rx(sk, rem_addr, tx_buf, exp_rx = True): |
| print('Tx ECHO_REQ to %r: %r' % (repr(rem_addr), repr(tx_buf))) |
| sk.sendto(tx_buf, rem_addr) |
| if exp_rx: |
| rx_buf = sk.recvfrom(BUF_SIZE) |
| msg = "Message from Server {}".format(rx_buf) |
| print(msg) |
| |
| if __name__ == '__main__': |
| p = argparse.ArgumentParser(description='Tester for gtp-echo-recorder.') |
| p.add_argument('-l', '--local-address', default='127.0.0.2', help="Local GTP address") |
| p.add_argument('-r', '--remote-address', default='127.0.0.1', help="Remote GTP address") |
| args = p.parse_args() |
| |
| print('Binding socket on %r...' % repr((args.local_address, GTP1C_PORT))) |
| family = socket.AF_INET if type(ip_address(args.local_address)) is IPv4Address else socket.AF_INET6 |
| sk = socket.socket(family=family, type=socket.SOCK_DGRAM) |
| sk.bind((args.local_address, GTP1C_PORT)); |
| |
| rem_addr = (args.remote_address, GTP1C_PORT) |
| |
| tx_rx(sk, rem_addr, gen_gtpc_v1_echo_req()) |
| tx_rx(sk, rem_addr, gen_gtpc_v1_echo_req(1, GTP_HDRv1_FLAG_S, seq=67)) |
| tx_rx(sk, rem_addr, gen_gtpc_v2_echo_req(0, seq=300, recovery=-1, node_features=-1)) |
| tx_rx(sk, rem_addr, gen_gtpc_v2_echo_req(0, seq=20, recovery=99, node_features=-1)) |
| tx_rx(sk, rem_addr, gen_gtpc_v2_echo_req(0, seq=20, recovery=100, node_features=0xbb)) |