<p>pespin has uploaded this change for <strong>review</strong>.</p><p><a href="https://gerrit.osmocom.org/c/osmo-ggsn/+/25652">View Change</a></p><pre style="font-family: monospace,monospace; white-space: pre-wrap;">WIP: gtp-echo-responder<br><br>Change-Id: Ibdd6d8f6920571db0c60cf8b3b25d541b15ad3f1<br>---<br>M Makefile.am<br>M configure.ac<br>M contrib/osmo-ggsn.spec.in<br>M debian/control<br>A debian/gtp-echo-responder.install<br>A utils/Makefile.am<br>A utils/gtp_echo_responder.c<br>A utils/gtp_echo_responder_test.py<br>8 files changed, 449 insertions(+), 1 deletion(-)<br><br></pre><pre style="font-family: monospace,monospace; white-space: pre-wrap;">git pull ssh://gerrit.osmocom.org:29418/osmo-ggsn refs/changes/52/25652/1</pre><pre style="font-family: monospace,monospace; white-space: pre-wrap;"><span>diff --git a/Makefile.am b/Makefile.am</span><br><span>index f431bd9..7fb2529 100644</span><br><span>--- a/Makefile.am</span><br><span>+++ b/Makefile.am</span><br><span>@@ -1,5 +1,5 @@</span><br><span> ## Process this file with automake to produce Makefile.in</span><br><span style="color: hsl(0, 100%, 40%);">-SUBDIRS = lib gtp ggsn sgsnemu doc contrib tests</span><br><span style="color: hsl(120, 100%, 40%);">+SUBDIRS = lib gtp ggsn sgsnemu doc contrib utils tests</span><br><span> </span><br><span> pkgconfigdir = $(libdir)/pkgconfig</span><br><span> pkgconfig_DATA = libgtp.pc</span><br><span>diff --git a/configure.ac b/configure.ac</span><br><span>index 2cf44fc..cfc9f21 100644</span><br><span>--- a/configure.ac</span><br><span>+++ b/configure.ac</span><br><span>@@ -257,6 +257,7 @@</span><br><span> lib/Makefile</span><br><span> intl/Makefile</span><br><span> po/Makefile</span><br><span style="color: hsl(120, 100%, 40%);">+ utils/Makefile</span><br><span> sgsnemu/Makefile</span><br><span> doc/manuals/Makefile</span><br><span> contrib/Makefile</span><br><span>diff --git a/contrib/osmo-ggsn.spec.in b/contrib/osmo-ggsn.spec.in</span><br><span>index 6d55af8..bee8fc1 100644</span><br><span>--- a/contrib/osmo-ggsn.spec.in</span><br><span>+++ b/contrib/osmo-ggsn.spec.in</span><br><span>@@ -61,6 +61,15 @@</span><br><span> This subpackage contains libraries and header files for developing</span><br><span> applications that want to make use of libgtp.</span><br><span> </span><br><span style="color: hsl(120, 100%, 40%);">+%package -n gtp-echo-responder</span><br><span style="color: hsl(120, 100%, 40%);">+Summary: Small program answering GTP ECHO Request with GTP ECHO Response</span><br><span style="color: hsl(120, 100%, 40%);">+License: MIT</span><br><span style="color: hsl(120, 100%, 40%);">+Group: System/Libraries</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+%description -n gtp-echo-responder</span><br><span style="color: hsl(120, 100%, 40%);">+Small program answering GTP ECHO Request with GTP ECHO Response for both GTPCv1</span><br><span style="color: hsl(120, 100%, 40%);">+and GTPCv2.</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span> %prep</span><br><span> %setup -q</span><br><span> </span><br><span>@@ -122,4 +131,7 @@</span><br><span> %{_libdir}/libgtp.so</span><br><span> %{_libdir}/pkgconfig/libgtp.pc</span><br><span> </span><br><span style="color: hsl(120, 100%, 40%);">+%files -n gtp-echo-responder</span><br><span style="color: hsl(120, 100%, 40%);">+%{_bindir}/gtp-echo-responder</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span> %changelog</span><br><span>diff --git a/debian/control b/debian/control</span><br><span>index bbffd49..6d5cde5 100644</span><br><span>--- a/debian/control</span><br><span>+++ b/debian/control</span><br><span>@@ -38,6 +38,12 @@</span><br><span> This library is part of OsmoGGSN and implements the GTP protocol between</span><br><span> SGSN (Serving GPRS support node) and GGSN.</span><br><span> </span><br><span style="color: hsl(120, 100%, 40%);">+Package: gtp-echo-responder</span><br><span style="color: hsl(120, 100%, 40%);">+Architecture: any</span><br><span style="color: hsl(120, 100%, 40%);">+Depends: ${shlibs:Depends},</span><br><span style="color: hsl(120, 100%, 40%);">+ ${misc:Depends}</span><br><span style="color: hsl(120, 100%, 40%);">+Description: Small program answering GTP ECHO Request with GTP ECHO Response</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span> Package: libgtp-dev</span><br><span> Architecture: any</span><br><span> Multi-Arch: same</span><br><span>@@ -63,6 +69,15 @@</span><br><span> operators as the interface between the Internet and the rest of the</span><br><span> mobile network infrastructure.</span><br><span> </span><br><span style="color: hsl(120, 100%, 40%);">+Package: gtp-echo-responder-dbg</span><br><span style="color: hsl(120, 100%, 40%);">+Section: debug</span><br><span style="color: hsl(120, 100%, 40%);">+Architecture: any</span><br><span style="color: hsl(120, 100%, 40%);">+Priority: extra</span><br><span style="color: hsl(120, 100%, 40%);">+Depends: ${shlibs:Depends}, ${misc:Depends}, gtp-echo-responder (= ${binary:Version})</span><br><span style="color: hsl(120, 100%, 40%);">+Multi-Arch: same</span><br><span style="color: hsl(120, 100%, 40%);">+Description: Debug symbols for gtp-echo-responder</span><br><span style="color: hsl(120, 100%, 40%);">+ Small program answering GTP ECHO Request with GTP ECHO Response.</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span> Package: libgtp-dbg</span><br><span> Section: debug</span><br><span> Architecture: any</span><br><span>diff --git a/debian/gtp-echo-responder.install b/debian/gtp-echo-responder.install</span><br><span>new file mode 100644</span><br><span>index 0000000..1d6d96f</span><br><span>--- /dev/null</span><br><span>+++ b/debian/gtp-echo-responder.install</span><br><span>@@ -0,0 +1 @@</span><br><span style="color: hsl(120, 100%, 40%);">+/usr/bin/gtp-echo-responder</span><br><span>diff --git a/utils/Makefile.am b/utils/Makefile.am</span><br><span>new file mode 100644</span><br><span>index 0000000..7ba0ff4</span><br><span>--- /dev/null</span><br><span>+++ b/utils/Makefile.am</span><br><span>@@ -0,0 +1,3 @@</span><br><span style="color: hsl(120, 100%, 40%);">+bin_PROGRAMS = gtp-echo-responder</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+gtp_echo_responder_SOURCES = gtp_echo_responder.c</span><br><span>diff --git a/utils/gtp_echo_responder.c b/utils/gtp_echo_responder.c</span><br><span>new file mode 100644</span><br><span>index 0000000..66479c7</span><br><span>--- /dev/null</span><br><span>+++ b/utils/gtp_echo_responder.c</span><br><span>@@ -0,0 +1,338 @@</span><br><span style="color: hsl(120, 100%, 40%);">+/*</span><br><span style="color: hsl(120, 100%, 40%);">+ * MIT License</span><br><span style="color: hsl(120, 100%, 40%);">+ *</span><br><span style="color: hsl(120, 100%, 40%);">+ * Copyright (c) 2021 by sysmocom - s.f.m.c. GmbH <info@sysmocom.de></span><br><span style="color: hsl(120, 100%, 40%);">+ *</span><br><span style="color: hsl(120, 100%, 40%);">+ * SPDX-License-Identifier: MIT Permission is hereby granted, free of charge, to</span><br><span style="color: hsl(120, 100%, 40%);">+ * any person obtaining a copy of this software and associated documentation</span><br><span style="color: hsl(120, 100%, 40%);">+ * files (the "Software"), to deal in the Software without restriction,</span><br><span style="color: hsl(120, 100%, 40%);">+ * including without limitation the rights to use, copy, modify, merge, publish,</span><br><span style="color: hsl(120, 100%, 40%);">+ * distribute, sublicense, and/or sell copies of the Software, and to permit</span><br><span style="color: hsl(120, 100%, 40%);">+ * persons to whom the Software is furnished to do so, subject to the following</span><br><span style="color: hsl(120, 100%, 40%);">+ * conditions:</span><br><span style="color: hsl(120, 100%, 40%);">+ *</span><br><span style="color: hsl(120, 100%, 40%);">+ * The above copyright notice and this permission notice (including the next</span><br><span style="color: hsl(120, 100%, 40%);">+ * paragraph) shall be included in all copies or substantial portions of the</span><br><span style="color: hsl(120, 100%, 40%);">+ * Software.</span><br><span style="color: hsl(120, 100%, 40%);">+ *</span><br><span style="color: hsl(120, 100%, 40%);">+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR</span><br><span style="color: hsl(120, 100%, 40%);">+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,</span><br><span style="color: hsl(120, 100%, 40%);">+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE</span><br><span style="color: hsl(120, 100%, 40%);">+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER</span><br><span style="color: hsl(120, 100%, 40%);">+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,</span><br><span style="color: hsl(120, 100%, 40%);">+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE</span><br><span style="color: hsl(120, 100%, 40%);">+ * SOFTWARE.</span><br><span style="color: hsl(120, 100%, 40%);">+ */</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+/* For more info see:</span><br><span style="color: hsl(120, 100%, 40%);">+ * 3GPP TS 29.060 (GTPv1 and GTPv0)</span><br><span style="color: hsl(120, 100%, 40%);">+ * 3GPP TS 29.274 (GTPv2C)</span><br><span style="color: hsl(120, 100%, 40%);">+ */</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+#include "../config.h"</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+#include <stdlib.h></span><br><span style="color: hsl(120, 100%, 40%);">+#include <stdbool.h></span><br><span style="color: hsl(120, 100%, 40%);">+#include <stdio.h></span><br><span style="color: hsl(120, 100%, 40%);">+#include <string.h></span><br><span style="color: hsl(120, 100%, 40%);">+#include <errno.h></span><br><span style="color: hsl(120, 100%, 40%);">+#include <getopt.h></span><br><span style="color: hsl(120, 100%, 40%);">+#include <netinet/in.h></span><br><span style="color: hsl(120, 100%, 40%);">+#include <arpa/inet.h></span><br><span style="color: hsl(120, 100%, 40%);">+#include <sys/select.h></span><br><span style="color: hsl(120, 100%, 40%);">+#include <sys/socket.h></span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+#define GTP1C_PORT 2123</span><br><span style="color: hsl(120, 100%, 40%);">+#define GTP_MSGTYPE_ECHO_REQ 1</span><br><span style="color: hsl(120, 100%, 40%);">+#define GTP_MSGTYPE_ECHO_RSP 2</span><br><span style="color: hsl(120, 100%, 40%);">+#define GTP_IE_RECOVERY 14</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+struct gtp1_hdr {</span><br><span style="color: hsl(120, 100%, 40%);">+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__</span><br><span style="color: hsl(120, 100%, 40%);">+ uint8_t pn:1, s:1, e:1, spare:1, pt:1, version:3;</span><br><span style="color: hsl(120, 100%, 40%);">+#else</span><br><span style="color: hsl(120, 100%, 40%);">+ uint8_t version:3, pt:1, spare:1, e:1, s:1, pn:1;</span><br><span style="color: hsl(120, 100%, 40%);">+#endif</span><br><span style="color: hsl(120, 100%, 40%);">+ uint8_t type;</span><br><span style="color: hsl(120, 100%, 40%);">+ uint16_t length;</span><br><span style="color: hsl(120, 100%, 40%);">+ uint32_t tei;</span><br><span style="color: hsl(120, 100%, 40%);">+ uint16_t seq;</span><br><span style="color: hsl(120, 100%, 40%);">+ uint8_t npdu;</span><br><span style="color: hsl(120, 100%, 40%);">+ uint8_t next;</span><br><span style="color: hsl(120, 100%, 40%);">+} __attribute__((packed));</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+struct gtp_echo_resp_state {</span><br><span style="color: hsl(120, 100%, 40%);">+ struct {</span><br><span style="color: hsl(120, 100%, 40%);">+ char laddr[INET6_ADDRSTRLEN];</span><br><span style="color: hsl(120, 100%, 40%);">+ uint8_t recovery_ctr;</span><br><span style="color: hsl(120, 100%, 40%);">+ } cfg;</span><br><span style="color: hsl(120, 100%, 40%);">+ struct sockaddr_storage laddr_gtpc1;</span><br><span style="color: hsl(120, 100%, 40%);">+ int fd_gtpc1;</span><br><span style="color: hsl(120, 100%, 40%);">+};</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+struct gtp_echo_resp_state *g_st;</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+static void print_usage(void)</span><br><span style="color: hsl(120, 100%, 40%);">+{</span><br><span style="color: hsl(120, 100%, 40%);">+ printf("Usage: gtp-echo-responder [-h] [-V] [-l listen_addr]\n");</span><br><span style="color: hsl(120, 100%, 40%);">+}</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+static void print_help(void)</span><br><span style="color: hsl(120, 100%, 40%);">+{</span><br><span style="color: hsl(120, 100%, 40%);">+ printf( " Some useful help...\n"</span><br><span style="color: hsl(120, 100%, 40%);">+ " -h --help This help text\n"</span><br><span style="color: hsl(120, 100%, 40%);">+ " -V --version Print the version of gtp-echo-responder\n"</span><br><span style="color: hsl(120, 100%, 40%);">+ );</span><br><span style="color: hsl(120, 100%, 40%);">+}</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+static void print_version(void)</span><br><span style="color: hsl(120, 100%, 40%);">+{</span><br><span style="color: hsl(120, 100%, 40%);">+ printf("gtp-echo-responder version %s\n", PACKAGE_VERSION);</span><br><span style="color: hsl(120, 100%, 40%);">+}</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+static void handle_options(int argc, char **argv)</span><br><span style="color: hsl(120, 100%, 40%);">+{</span><br><span style="color: hsl(120, 100%, 40%);">+ while (1) {</span><br><span style="color: hsl(120, 100%, 40%);">+ int option_index = 0, c;</span><br><span style="color: hsl(120, 100%, 40%);">+ static struct option long_options[] = {</span><br><span style="color: hsl(120, 100%, 40%);">+ { "help", 0, 0, 'h' },</span><br><span style="color: hsl(120, 100%, 40%);">+ { "version", 0, 0, 'V' },</span><br><span style="color: hsl(120, 100%, 40%);">+ {"listen-addr", 1, 0, 'l'},</span><br><span style="color: hsl(120, 100%, 40%);">+ {"recovery-counter", 1, 0, 'R'},</span><br><span style="color: hsl(120, 100%, 40%);">+ { 0, 0, 0, 0 }</span><br><span style="color: hsl(120, 100%, 40%);">+ };</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ c = getopt_long(argc, argv, "hdVl:R:", long_options, &option_index);</span><br><span style="color: hsl(120, 100%, 40%);">+ if (c == -1)</span><br><span style="color: hsl(120, 100%, 40%);">+ break;</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ switch (c) {</span><br><span style="color: hsl(120, 100%, 40%);">+ case 'h':</span><br><span style="color: hsl(120, 100%, 40%);">+ print_usage();</span><br><span style="color: hsl(120, 100%, 40%);">+ print_help();</span><br><span style="color: hsl(120, 100%, 40%);">+ exit(0);</span><br><span style="color: hsl(120, 100%, 40%);">+ case 'V':</span><br><span style="color: hsl(120, 100%, 40%);">+ print_version();</span><br><span style="color: hsl(120, 100%, 40%);">+ exit(0);</span><br><span style="color: hsl(120, 100%, 40%);">+ break;</span><br><span style="color: hsl(120, 100%, 40%);">+ case 'l':</span><br><span style="color: hsl(120, 100%, 40%);">+ strncpy(&g_st->cfg.laddr[0], optarg, sizeof(g_st->cfg.laddr));</span><br><span style="color: hsl(120, 100%, 40%);">+ g_st->cfg.laddr[sizeof(g_st->cfg.laddr) - 1] = '\0';</span><br><span style="color: hsl(120, 100%, 40%);">+ break;</span><br><span style="color: hsl(120, 100%, 40%);">+ case 'R':</span><br><span style="color: hsl(120, 100%, 40%);">+ g_st->cfg.recovery_ctr = (uint8_t)atoi(optarg);</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+}</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+static int init_socket(void)</span><br><span style="color: hsl(120, 100%, 40%);">+{</span><br><span style="color: hsl(120, 100%, 40%);">+ struct in_addr addr;</span><br><span style="color: hsl(120, 100%, 40%);">+ struct in6_addr addr6;</span><br><span style="color: hsl(120, 100%, 40%);">+ struct sockaddr_in *saddr;</span><br><span style="color: hsl(120, 100%, 40%);">+ struct sockaddr_in6 *saddr6;</span><br><span style="color: hsl(120, 100%, 40%);">+ int family;</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ if (inet_pton(AF_INET6, g_st->cfg.laddr, &addr6) == 1) {</span><br><span style="color: hsl(120, 100%, 40%);">+ family = AF_INET6;</span><br><span style="color: hsl(120, 100%, 40%);">+ saddr6 = (struct sockaddr_in6 *)&g_st->laddr_gtpc1;</span><br><span style="color: hsl(120, 100%, 40%);">+ saddr6->sin6_family = family;</span><br><span style="color: hsl(120, 100%, 40%);">+ saddr6->sin6_port = htons(GTP1C_PORT);</span><br><span style="color: hsl(120, 100%, 40%);">+ memcpy(&saddr6->sin6_addr, &addr6, sizeof(addr6));</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ } else if (inet_pton(AF_INET, g_st->cfg.laddr, &addr) == 1) {</span><br><span style="color: hsl(120, 100%, 40%);">+ family = AF_INET;</span><br><span style="color: hsl(120, 100%, 40%);">+ saddr = (struct sockaddr_in *)&g_st->laddr_gtpc1;</span><br><span style="color: hsl(120, 100%, 40%);">+ saddr->sin_family = family;</span><br><span style="color: hsl(120, 100%, 40%);">+ saddr->sin_port = htons(GTP1C_PORT);</span><br><span style="color: hsl(120, 100%, 40%);">+ memcpy(&saddr->sin_addr, &addr, sizeof(addr));</span><br><span style="color: hsl(120, 100%, 40%);">+ } else {</span><br><span style="color: hsl(120, 100%, 40%);">+ fprintf(stderr, "Failed parsing address %s\n", g_st->cfg.laddr);</span><br><span style="color: hsl(120, 100%, 40%);">+ return -1;</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ if ((g_st->fd_gtpc1 = socket(family, SOCK_DGRAM, 0)) < 0) {</span><br><span style="color: hsl(120, 100%, 40%);">+ fprintf(stderr, "socket() failed: %s\n", strerror(errno));</span><br><span style="color: hsl(120, 100%, 40%);">+ return -2;</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ if (bind(g_st->fd_gtpc1, (struct sockaddr *)&g_st->laddr_gtpc1, sizeof(g_st->laddr_gtpc1)) < 0) {</span><br><span style="color: hsl(120, 100%, 40%);">+ fprintf(stderr, "bind() failed: %s\n", strerror(errno));</span><br><span style="color: hsl(120, 100%, 40%);">+ return -3;</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ return 0;</span><br><span style="color: hsl(120, 100%, 40%);">+}</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+static const char* sockaddr2str(const struct sockaddr* saddr)</span><br><span style="color: hsl(120, 100%, 40%);">+{</span><br><span style="color: hsl(120, 100%, 40%);">+ static char _rem_addr_str[INET6_ADDRSTRLEN];</span><br><span style="color: hsl(120, 100%, 40%);">+ struct sockaddr_in *saddr4;</span><br><span style="color: hsl(120, 100%, 40%);">+ struct sockaddr_in6 *saddr6;</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ switch (saddr->sa_family) {</span><br><span style="color: hsl(120, 100%, 40%);">+ case AF_INET6:</span><br><span style="color: hsl(120, 100%, 40%);">+ saddr6 = (struct sockaddr_in6 *)saddr;</span><br><span style="color: hsl(120, 100%, 40%);">+ if (!inet_ntop(saddr6->sin6_family, &saddr6->sin6_addr, _rem_addr_str, sizeof(_rem_addr_str)))</span><br><span style="color: hsl(120, 100%, 40%);">+ goto err;</span><br><span style="color: hsl(120, 100%, 40%);">+ return _rem_addr_str;</span><br><span style="color: hsl(120, 100%, 40%);">+ case AF_INET:</span><br><span style="color: hsl(120, 100%, 40%);">+ saddr4 = (struct sockaddr_in *)saddr;</span><br><span style="color: hsl(120, 100%, 40%);">+ if (!inet_ntop(saddr4->sin_family, &saddr4->sin_addr, _rem_addr_str, sizeof(_rem_addr_str)))</span><br><span style="color: hsl(120, 100%, 40%);">+ goto err;</span><br><span style="color: hsl(120, 100%, 40%);">+ return _rem_addr_str;</span><br><span style="color: hsl(120, 100%, 40%);">+ default:</span><br><span style="color: hsl(120, 100%, 40%);">+ /* fall through */</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+err:</span><br><span style="color: hsl(120, 100%, 40%);">+ strcpy(_rem_addr_str, "unknwown");</span><br><span style="color: hsl(120, 100%, 40%);">+ return _rem_addr_str;</span><br><span style="color: hsl(120, 100%, 40%);">+}</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+static int write_cb(int fd, const uint8_t *buf, size_t buf_len, const struct sockaddr* rem_saddr)</span><br><span style="color: hsl(120, 100%, 40%);">+{</span><br><span style="color: hsl(120, 100%, 40%);">+ ssize_t rc;</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ rc = sendto(fd, buf, buf_len, 0, rem_saddr, sizeof(struct sockaddr_storage));</span><br><span style="color: hsl(120, 100%, 40%);">+ if (rc < 0) {</span><br><span style="color: hsl(120, 100%, 40%);">+ fprintf(stderr, "sendto() failed: %s\n", strerror(errno));</span><br><span style="color: hsl(120, 100%, 40%);">+ return -1;</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+ if (rc != buf_len) {</span><br><span style="color: hsl(120, 100%, 40%);">+ fprintf(stderr, "sendto() short write: %u vs exp %u\n", rc, buf_len);</span><br><span style="color: hsl(120, 100%, 40%);">+ return -1;</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+ return 0;</span><br><span style="color: hsl(120, 100%, 40%);">+}</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+static int gen_gtpc1_echo_rsp(uint8_t *buf, struct gtp1_hdr *echo_req)</span><br><span style="color: hsl(120, 100%, 40%);">+{</span><br><span style="color: hsl(120, 100%, 40%);">+ int offset = 0;</span><br><span style="color: hsl(120, 100%, 40%);">+ struct gtp1_hdr *echo_rsp = (struct gtp1_hdr *)buf;</span><br><span style="color: hsl(120, 100%, 40%);">+ unsigned exp_hdr_len = (echo_req->s || echo_req->pn || echo_req->e) ? 12 : 8;</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ memcpy(echo_rsp, echo_req, exp_hdr_len);</span><br><span style="color: hsl(120, 100%, 40%);">+ echo_rsp->type = GTP_MSGTYPE_ECHO_RSP;</span><br><span style="color: hsl(120, 100%, 40%);">+ offset = exp_hdr_len;</span><br><span style="color: hsl(120, 100%, 40%);">+ buf[offset++] = GTP_IE_RECOVERY;</span><br><span style="color: hsl(120, 100%, 40%);">+ buf[offset++] = g_st->cfg.recovery_ctr;</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ /* Update Length */</span><br><span style="color: hsl(120, 100%, 40%);">+ echo_rsp->length = htons(offset - 8);</span><br><span style="color: hsl(120, 100%, 40%);">+ return offset;</span><br><span style="color: hsl(120, 100%, 40%);">+}</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+static int rx_gtpc1_echo_req(struct gtp1_hdr *echo_req, unsigned buf_len, const struct sockaddr* rem_saddr)</span><br><span style="color: hsl(120, 100%, 40%);">+{</span><br><span style="color: hsl(120, 100%, 40%);">+ int rc;</span><br><span style="color: hsl(120, 100%, 40%);">+ const size_t tx_buf_len = buf_len + 128; /* Leave some extra room */</span><br><span style="color: hsl(120, 100%, 40%);">+ uint8_t *tx_buf = alloca(tx_buf_len);</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ printf("Rx GTPCv1_ECHO_REQ from %s, Tx GTPCv1_ECHO_RSP\n", sockaddr2str(rem_saddr));</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ memset(tx_buf, 0, tx_buf_len);</span><br><span style="color: hsl(120, 100%, 40%);">+ rc = gen_gtpc1_echo_rsp(tx_buf, echo_req);</span><br><span style="color: hsl(120, 100%, 40%);">+ return write_cb(g_st->fd_gtpc1, tx_buf, rc, rem_saddr);</span><br><span style="color: hsl(120, 100%, 40%);">+}</span><br><span style="color: hsl(120, 100%, 40%);">+static int rx_gtpc1(struct gtp1_hdr *hdr, unsigned buf_len, const struct sockaddr* rem_saddr)</span><br><span style="color: hsl(120, 100%, 40%);">+{</span><br><span style="color: hsl(120, 100%, 40%);">+ unsigned exp_hdr_len = (hdr->s || hdr->pn || hdr->e) ? 12 : 8;</span><br><span style="color: hsl(120, 100%, 40%);">+ unsigned pdu_len;</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ if (buf_len < exp_hdr_len) {</span><br><span style="color: hsl(120, 100%, 40%);">+ fprintf(stderr, "GTPCv1 packet size smaller than header! %u < exp %u\n", buf_len, exp_hdr_len);</span><br><span style="color: hsl(120, 100%, 40%);">+ return -1;</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ pdu_len = ntohs(hdr->length);</span><br><span style="color: hsl(120, 100%, 40%);">+ if (buf_len < 8 + pdu_len) {</span><br><span style="color: hsl(120, 100%, 40%);">+ fprintf(stderr, "GTPCv1 packet size smaller than announced! %u < exp %u\n", buf_len, 8 + pdu_len);</span><br><span style="color: hsl(120, 100%, 40%);">+ return -1;</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ if (hdr->pt != 1) {</span><br><span style="color: hsl(120, 100%, 40%);">+ fprintf(stderr, "GTPCv1 Protocol Type GTP' not supported!\n");</span><br><span style="color: hsl(120, 100%, 40%);">+ return -1;</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ switch (hdr->type) {</span><br><span style="color: hsl(120, 100%, 40%);">+ case GTP_MSGTYPE_ECHO_REQ:</span><br><span style="color: hsl(120, 100%, 40%);">+ return rx_gtpc1_echo_req(hdr, buf_len, rem_saddr);</span><br><span style="color: hsl(120, 100%, 40%);">+ default:</span><br><span style="color: hsl(120, 100%, 40%);">+ fprintf(stderr, "Silently ignoring unexpected packet of type %u\n", hdr->type);</span><br><span style="color: hsl(120, 100%, 40%);">+ return 0;</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+}</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+static int read_cb(int fd)</span><br><span style="color: hsl(120, 100%, 40%);">+{</span><br><span style="color: hsl(120, 100%, 40%);">+ ssize_t sz;</span><br><span style="color: hsl(120, 100%, 40%);">+ uint8_t buf[4096];</span><br><span style="color: hsl(120, 100%, 40%);">+ struct sockaddr_storage rem_saddr;</span><br><span style="color: hsl(120, 100%, 40%);">+ socklen_t rem_saddr_len = sizeof(rem_saddr);</span><br><span style="color: hsl(120, 100%, 40%);">+ struct gtp1_hdr *hdr1;</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ if ((sz = recvfrom(fd, buf, sizeof(buf), 0, (struct sockaddr *)&rem_saddr, &rem_saddr_len)) < 0) {</span><br><span style="color: hsl(120, 100%, 40%);">+ fprintf(stderr, "recvfrom() failed: %s\n", strerror(errno));</span><br><span style="color: hsl(120, 100%, 40%);">+ return -1;</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+ if (sz == 0) {</span><br><span style="color: hsl(120, 100%, 40%);">+ fprintf(stderr, "recvfrom() read zero bytes!\n");</span><br><span style="color: hsl(120, 100%, 40%);">+ return -1;</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ hdr1 = (struct gtp1_hdr *)&buf[0];</span><br><span style="color: hsl(120, 100%, 40%);">+ switch (hdr1->version) {</span><br><span style="color: hsl(120, 100%, 40%);">+ case 1:</span><br><span style="color: hsl(120, 100%, 40%);">+ return rx_gtpc1(hdr1, sz, (const struct sockaddr *)&rem_saddr);</span><br><span style="color: hsl(120, 100%, 40%);">+ default:</span><br><span style="color: hsl(120, 100%, 40%);">+ fprintf(stderr, "Rx GTPv%u: not supported (flags=0x%x)\n", hdr1->version, buf[0]);</span><br><span style="color: hsl(120, 100%, 40%);">+ return -1;</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+}</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+static int loop(void)</span><br><span style="color: hsl(120, 100%, 40%);">+{</span><br><span style="color: hsl(120, 100%, 40%);">+ int rc;</span><br><span style="color: hsl(120, 100%, 40%);">+ fd_set rfds;</span><br><span style="color: hsl(120, 100%, 40%);">+ int nfds;</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ while (true) {</span><br><span style="color: hsl(120, 100%, 40%);">+ FD_ZERO(&rfds);</span><br><span style="color: hsl(120, 100%, 40%);">+ FD_SET(g_st->fd_gtpc1, &rfds);</span><br><span style="color: hsl(120, 100%, 40%);">+ nfds = g_st->fd_gtpc1 + 1;</span><br><span style="color: hsl(120, 100%, 40%);">+ rc = select(nfds, &rfds, NULL, NULL, NULL);</span><br><span style="color: hsl(120, 100%, 40%);">+ if (rc == 0)</span><br><span style="color: hsl(120, 100%, 40%);">+ continue;</span><br><span style="color: hsl(120, 100%, 40%);">+ if (rc < 0) {</span><br><span style="color: hsl(120, 100%, 40%);">+ fprintf(stderr, "select() failed: %s\n", strerror(errno));</span><br><span style="color: hsl(120, 100%, 40%);">+ return -1;</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ if (FD_ISSET(g_st->fd_gtpc1, &rfds)) {</span><br><span style="color: hsl(120, 100%, 40%);">+ read_cb(g_st->fd_gtpc1);</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+}</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+int main(int argc, char **argv)</span><br><span style="color: hsl(120, 100%, 40%);">+{</span><br><span style="color: hsl(120, 100%, 40%);">+ g_st = calloc(1, sizeof(struct gtp_echo_resp_state));</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ strcpy(g_st->cfg.laddr, "::");</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ handle_options(argc, argv);</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ printf("Listening on: %s\n", g_st->cfg.laddr);</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ if (init_socket() < 0)</span><br><span style="color: hsl(120, 100%, 40%);">+ exit(1);</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ printf("Socket bound successfuly, listening for requests...\n");</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ if (loop() < 0)</span><br><span style="color: hsl(120, 100%, 40%);">+ exit(1);</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ return 0;</span><br><span style="color: hsl(120, 100%, 40%);">+}</span><br><span>diff --git a/utils/gtp_echo_responder_test.py b/utils/gtp_echo_responder_test.py</span><br><span>new file mode 100755</span><br><span>index 0000000..e90b129</span><br><span>--- /dev/null</span><br><span>+++ b/utils/gtp_echo_responder_test.py</span><br><span>@@ -0,0 +1,78 @@</span><br><span style="color: hsl(120, 100%, 40%);">+#!/usr/bin/env python3</span><br><span style="color: hsl(120, 100%, 40%);">+# MIT License</span><br><span style="color: hsl(120, 100%, 40%);">+#</span><br><span style="color: hsl(120, 100%, 40%);">+# Copyright (c) 2021 by sysmocom - s.f.m.c. GmbH <info@sysmocom.de></span><br><span style="color: hsl(120, 100%, 40%);">+#</span><br><span style="color: hsl(120, 100%, 40%);">+# SPDX-License-Identifier: MIT Permission is hereby granted, free of charge, to</span><br><span style="color: hsl(120, 100%, 40%);">+# any person obtaining a copy of this software and associated documentation</span><br><span style="color: hsl(120, 100%, 40%);">+# files (the "Software"), to deal in the Software without restriction,</span><br><span style="color: hsl(120, 100%, 40%);">+# including without limitation the rights to use, copy, modify, merge, publish,</span><br><span style="color: hsl(120, 100%, 40%);">+# distribute, sublicense, and/or sell copies of the Software, and to permit</span><br><span style="color: hsl(120, 100%, 40%);">+# persons to whom the Software is furnished to do so, subject to the following</span><br><span style="color: hsl(120, 100%, 40%);">+# conditions:</span><br><span style="color: hsl(120, 100%, 40%);">+#</span><br><span style="color: hsl(120, 100%, 40%);">+# The above copyright notice and this permission notice (including the next</span><br><span style="color: hsl(120, 100%, 40%);">+# paragraph) shall be included in all copies or substantial portions of the</span><br><span style="color: hsl(120, 100%, 40%);">+# Software.</span><br><span style="color: hsl(120, 100%, 40%);">+#</span><br><span style="color: hsl(120, 100%, 40%);">+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR</span><br><span style="color: hsl(120, 100%, 40%);">+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,</span><br><span style="color: hsl(120, 100%, 40%);">+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE</span><br><span style="color: hsl(120, 100%, 40%);">+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER</span><br><span style="color: hsl(120, 100%, 40%);">+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,</span><br><span style="color: hsl(120, 100%, 40%);">+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE</span><br><span style="color: hsl(120, 100%, 40%);">+# SOFTWARE.</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+import socket</span><br><span style="color: hsl(120, 100%, 40%);">+import argparse</span><br><span style="color: hsl(120, 100%, 40%);">+import struct</span><br><span style="color: hsl(120, 100%, 40%);">+from ipaddress import ip_address, IPv4Address</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+GTP1C_PORT = 2123</span><br><span style="color: hsl(120, 100%, 40%);">+BUF_SIZE = 4096</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+GTP_HDRv1_FLAG_PN = (1<<0)</span><br><span style="color: hsl(120, 100%, 40%);">+GTP_HDRv1_FLAG_S = (1<<1)</span><br><span style="color: hsl(120, 100%, 40%);">+GTP_HDRv1_FLAG_E = (1<<2)</span><br><span style="color: hsl(120, 100%, 40%);">+GTP_HDRv1_PT_GTP = (1<<4)</span><br><span style="color: hsl(120, 100%, 40%);">+GTP_HDRv1_VER_GTP1 = (1<<5)</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+def gen_gtpc_v1_hdr(flags, type, length, tei, seq=0, npdu=0, next=0):</span><br><span style="color: hsl(120, 100%, 40%);">+ spare = 0</span><br><span style="color: hsl(120, 100%, 40%);">+ if (flags & (GTP_HDRv1_FLAG_PN|GTP_HDRv1_FLAG_S|GTP_HDRv1_FLAG_E)):</span><br><span style="color: hsl(120, 100%, 40%);">+ #long format</span><br><span style="color: hsl(120, 100%, 40%);">+ length += 4</span><br><span style="color: hsl(120, 100%, 40%);">+ d = struct.pack('!BBHIHBB',flags, type, length, tei, seq, npdu, next)</span><br><span style="color: hsl(120, 100%, 40%);">+ else:</span><br><span style="color: hsl(120, 100%, 40%);">+ #short format</span><br><span style="color: hsl(120, 100%, 40%);">+ d = struct.pack('!BBHI',flags, type, length, tei)</span><br><span style="color: hsl(120, 100%, 40%);">+ return d</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+def gen_gtpc_v1_echo_req(tei=0, append_flags=0, seq=0, npdu=0, next=0):</span><br><span style="color: hsl(120, 100%, 40%);">+ return gen_gtpc_v1_hdr(GTP_HDRv1_VER_GTP1 | GTP_HDRv1_PT_GTP | append_flags, 1, 0, tei, seq, npdu, next)</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+def tx_rx(sk, rem_addr, tx_buf, exp_rx = True):</span><br><span style="color: hsl(120, 100%, 40%);">+ print('Tx ECHO_REQ to %r: %r' % (repr(rem_addr), repr(tx_buf)))</span><br><span style="color: hsl(120, 100%, 40%);">+ sk.sendto(tx_buf, rem_addr)</span><br><span style="color: hsl(120, 100%, 40%);">+ if exp_rx:</span><br><span style="color: hsl(120, 100%, 40%);">+ rx_buf = sk.recvfrom(BUF_SIZE)</span><br><span style="color: hsl(120, 100%, 40%);">+ msg = "Message from Server {}".format(rx_buf)</span><br><span style="color: hsl(120, 100%, 40%);">+ print(msg)</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+if __name__ == '__main__':</span><br><span style="color: hsl(120, 100%, 40%);">+ p = argparse.ArgumentParser(description='Tester for gtp-echo-recorder.')</span><br><span style="color: hsl(120, 100%, 40%);">+ p.add_argument('-l', '--local-address', default='127.0.0.2', help="Local GTP address")</span><br><span style="color: hsl(120, 100%, 40%);">+ p.add_argument('-r', '--remote-address', default='127.0.0.1', help="Remote GTP address")</span><br><span style="color: hsl(120, 100%, 40%);">+ args = p.parse_args()</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ print('Binding socket on %r...' % repr((args.local_address, GTP1C_PORT)))</span><br><span style="color: hsl(120, 100%, 40%);">+ family = socket.AF_INET if type(ip_address(args.local_address)) is IPv4Address else socket.AF_INET6</span><br><span style="color: hsl(120, 100%, 40%);">+ sk = socket.socket(family=family, type=socket.SOCK_DGRAM)</span><br><span style="color: hsl(120, 100%, 40%);">+ sk.bind((args.local_address, GTP1C_PORT));</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ rem_addr = (args.remote_address, GTP1C_PORT)</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ tx_rx(sk, rem_addr, gen_gtpc_v1_echo_req())</span><br><span style="color: hsl(120, 100%, 40%);">+ tx_rx(sk, rem_addr, gen_gtpc_v1_echo_req(1, GTP_HDRv1_FLAG_S, seq=67))</span><br><span></span><br></pre><p>To view, visit <a href="https://gerrit.osmocom.org/c/osmo-ggsn/+/25652">change 25652</a>. To unsubscribe, or for help writing mail filters, visit <a href="https://gerrit.osmocom.org/settings">settings</a>.</p><div itemscope itemtype="http://schema.org/EmailMessage"><div itemscope itemprop="action" itemtype="http://schema.org/ViewAction"><link itemprop="url" href="https://gerrit.osmocom.org/c/osmo-ggsn/+/25652"/><meta itemprop="name" content="View Change"/></div></div>
<div style="display:none"> Gerrit-Project: osmo-ggsn </div>
<div style="display:none"> Gerrit-Branch: master </div>
<div style="display:none"> Gerrit-Change-Id: Ibdd6d8f6920571db0c60cf8b3b25d541b15ad3f1 </div>
<div style="display:none"> Gerrit-Change-Number: 25652 </div>
<div style="display:none"> Gerrit-PatchSet: 1 </div>
<div style="display:none"> Gerrit-Owner: pespin <pespin@sysmocom.de> </div>
<div style="display:none"> Gerrit-MessageType: newchange </div>