add osmo-pfcp-tool

Related: SYS#5599
Change-Id: I34a80d43a14c7b68952c7d337d8042d6f28ceae7

configure.ac

@@ -207,6 +207,7 @@ AC_OUTPUT(
     src/libosmo-gtlv/Makefile
     src/libosmo-pfcp/Makefile
     src/osmo-upf/Makefile
+    src/osmo-pfcp-tool/Makefile
     tests/Makefile
     tests/atlocal
     tests/libosmo-gtlv/Makefile

contrib/osmo-pfcp-tool-scripts/assoc_setup.vty

@@ -0,0 +1,3 @@
+pfcp-peer 127.0.0.1
+ tx assoc-setup-req
+ sleep 1

contrib/osmo-pfcp-tool-scripts/assoc_setup_retrans.vty

@@ -0,0 +1,8 @@
+pfcp-peer 127.0.0.1
+ tx assoc-setup-req
+ sleep 3
+ retrans req
+ sleep 5
+ retrans req
+ sleep 1
+ retrans req

contrib/osmo-pfcp-tool-scripts/encaps_plus_tunmap.vty

@@ -0,0 +1,30 @@
+# ACCESS                HOP                           CORE
+#                       session 23 = tunmap           session 42 = encaps/decaps
+# GTP 127.0.0.13        127.0.0.12                    127.0.0.11
+# TEID l:23 r:123 <---> r:23 l:123 | l:142 r:42 <---> r:142 l:42 | 192.168.100.42
+#
+# Run two UPF, one listening on / sending from 127.0.0.11, the other on 127.0.0.12.
+# (Each has to match on the sender address of incoming GTP packets.)
+
+timer pfcp x23 0
+
+pfcp-peer 127.0.0.11
+ tx assoc-setup-req
+ sleep 1
+ session endecaps 42
+  ue ip 192.168.100.42
+  gtp access ip 127.0.0.12
+  gtp access teid local 42 remote 142
+  tx session-est-req
+ sleep 1
+
+pfcp-peer 127.0.0.12
+ tx assoc-setup-req
+ sleep 1
+ session tunmap 23
+  gtp core ip 127.0.0.11
+  gtp core teid local 142 remote 42
+  gtp access ip 127.0.0.13
+  gtp access teid local 123 remote 23
+  tx session-est-req
+ sleep 1

contrib/osmo-pfcp-tool-scripts/endecaps_session_est.vty

@@ -0,0 +1,8 @@
+timer pfcp x23 0
+pfcp-peer 127.0.0.1
+ tx assoc-setup-req
+ sleep 1
+ session endecaps
+  tx session-est-req forw
+  sleep 5
+  tx session-del-req

contrib/osmo-pfcp-tool-scripts/heartbeat.vty

@@ -0,0 +1,10 @@
+pfcp-peer 127.0.0.1
+ tx heartbeat
+ sleep 2
+ tx heartbeat
+ sleep 2
+ tx heartbeat
+ sleep 2
+ tx heartbeat
+ sleep 2
+ tx heartbeat

contrib/osmo-pfcp-tool-scripts/osmo-pfcp-tool.cfg

@@ -0,0 +1,5 @@
+log stderr
+ logging level set-all info
+
+local-addr 127.0.0.2
+listen

contrib/osmo-pfcp-tool-scripts/osmo-upf-11.cfg

@@ -0,0 +1,27 @@
+log stderr
+ logging filter all 1
+ logging color 1
+ logging print level 1
+ logging print category 1
+ logging print category-hex 0
+ logging print file basename last
+ logging print extended-timestamp 1
+ logging level set-all notice
+ logging level set-all info
+ logging level session debug
+ logging level nft debug
+ logging level gtp debug
+#logging level set-all debug
+
+line vty
+ bind 127.0.0.11
+ctrl
+ bind 127.0.0.11
+
+timer pfcp x24 5000
+pfcp
+ local-addr 127.0.0.11
+gtp
+ dev create apn11 127.0.0.11
+nft
+ table-name osmo-upf-11

contrib/osmo-pfcp-tool-scripts/osmo-upf-12.cfg

@@ -0,0 +1,27 @@
+log stderr
+ logging filter all 1
+ logging color 1
+ logging print level 1
+ logging print category 1
+ logging print category-hex 0
+ logging print file basename last
+ logging print extended-timestamp 1
+ logging level set-all notice
+ logging level set-all info
+ logging level session debug
+ logging level nft debug
+ logging level gtp debug
+#logging level set-all debug
+
+line vty
+ bind 127.0.0.12
+ctrl
+ bind 127.0.0.12
+
+timer pfcp x24 5000
+pfcp
+ local-addr 127.0.0.12
+gtp
+ dev create apn12 127.0.0.12
+nft
+ table-name osmo-upf-12

contrib/osmo-pfcp-tool-scripts/session_est_without_assoc.vty

@@ -0,0 +1,4 @@
+timer pfcp x23 0
+pfcp-peer 127.0.0.1
+ session endecaps
+  tx session-est-req

contrib/osmo-pfcp-tool-scripts/session_mod.vty

@@ -0,0 +1,14 @@
+timer pfcp x23 0
+pfcp-peer 127.0.0.1
+ tx assoc-setup-req
+ sleep 1
+ session
+  tx session-est-req drop
+  sleep 3
+  tx session-mod-req forw
+  sleep 5
+  tx session-mod-req drop
+  sleep 3
+  tx session-mod-req forw
+  sleep 3
+  tx session-del-req

contrib/osmo-pfcp-tool-scripts/tunmap_session_est.vty

@@ -0,0 +1,8 @@
+timer pfcp x23 0
+pfcp-peer 127.0.0.1
+ tx assoc-setup-req
+ sleep 1
+ session tunmap
+  tx session-est-req
+  sleep 5
+  tx session-del-req

src/Makefile.am

@@ -2,4 +2,5 @@ SUBDIRS = \
 	libosmo-gtlv \
 	libosmo-pfcp \
 	osmo-upf \
+	osmo-pfcp-tool \
 	$(NULL)

src/osmo-pfcp-tool/Makefile.am

@@ -0,0 +1,41 @@
+AM_CPPFLAGS = \
+	$(all_includes) \
+	-I$(top_srcdir)/include \
+	-I$(top_builddir)/include \
+	-I$(top_builddir) \
+	$(NULL)
+
+AM_CFLAGS = \
+	-Wall \
+	$(LIBOSMOCORE_CFLAGS) \
+	$(LIBOSMOVTY_CFLAGS) \
+	$(LIBOSMOCTRL_CFLAGS) \
+	$(COVERAGE_CFLAGS) \
+	$(NULL)
+
+AM_LDFLAGS = \
+	$(COVERAGE_LDFLAGS) \
+	$(NULL)
+
+noinst_HEADERS = \
+	pfcp_tool.h \
+	$(NULL)
+
+bin_PROGRAMS = \
+	osmo-pfcp-tool \
+	$(NULL)
+
+osmo_pfcp_tool_SOURCES = \
+	osmo_pfcp_tool_main.c \
+	pfcp_tool.c \
+	pfcp_tool_vty.c \
+	$(NULL)
+
+osmo_pfcp_tool_LDADD = \
+	$(top_builddir)/src/libosmo-pfcp/libosmo-pfcp.a \
+	$(top_builddir)/src/libosmo-gtlv/libosmo-gtlv.a \
+	$(LIBOSMOCORE_LIBS) \
+	$(LIBOSMOVTY_LIBS) \
+	$(LIBOSMOCTRL_LIBS) \
+	$(COVERAGE_LDFLAGS) \
+	$(NULL)

src/osmo-pfcp-tool/osmo_pfcp_tool_main.c

@@ -0,0 +1,371 @@
+/*
+ * (C) 2021-2022 by sysmocom - s.f.m.c. GmbH <info@sysmocom.de>
+ * All Rights Reserved.
+ *
+ * Author: Neels Janosch Hofmeyr <nhofmeyr@sysmocom.de>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include <osmocom/core/application.h>
+#include <osmocom/core/signal.h>
+#include <osmocom/core/talloc.h>
+#include <osmocom/core/logging.h>
+#include <osmocom/core/fsm.h>
+#include <osmocom/core/stats.h>
+#include <osmocom/core/msgb.h>
+#include <osmocom/vty/logging.h>
+#include <osmocom/vty/command.h>
+#include <osmocom/vty/misc.h>
+#include <osmocom/vty/cpu_sched_vty.h>
+#include <osmocom/vty/telnet_interface.h>
+#include <osmocom/vty/ports.h>
+#include <osmocom/vty/tdef_vty.h>
+#include <osmocom/ctrl/control_if.h>
+#include <osmocom/ctrl/control_vty.h>
+#include <osmocom/ctrl/ports.h>
+#include <osmocom/core/sockaddr_str.h>
+
+#include <osmocom/pfcp/pfcp_endpoint.h>
+
+#include "pfcp_tool.h"
+
+#define _GNU_SOURCE
+#include <getopt.h>
+
+/* build switches from the configure script */
+#include "config.h"
+
+#include <signal.h>
+#include <stdio.h>
+#include <string.h>
+
+extern void *tall_vty_ctx;
+
+void *tall_pfcp_tool_ctx = NULL;
+static int quit = 0;
+
+static struct {
+	const char *config_file;
+	int daemonize;
+	enum vty_ref_gen_mode vty_ref_gen_mode;
+	const char *command_file;
+} pfcp_tool_cmdline_config = {
+	.config_file = "osmo-pfcp-tool.cfg",
+	.vty_ref_gen_mode = VTY_REF_GEN_MODE_DEFAULT,
+};
+
+static void print_usage()
+{
+	printf("Usage: osmo-pfcp-tool [command-file.vty]\n       telnet localhost %d\n", OSMO_VTY_PORT_PFCP_TOOL);
+}
+
+static void print_help()
+{
+	const struct value_string *vty_ref_gen_mode_name;
+
+	printf("Some useful options:\n");
+	printf("  -h --help                  This text.\n");
+	printf("  -D --daemonize             Fork the process into a background daemon.\n");
+	printf("  -c --config-file filename  The config file to use, for logging etc.\n");
+	printf("  -V --version               Print the version of OsmoMSC.\n");
+
+	printf("\nVTY reference generation:\n");
+	printf("     --vty-ref-xml           Generate the VTY reference XML output and exit.\n");
+	printf("     --vty-ref-mode MODE     Mode for --vty-ref-xml:\n");
+	/* List all VTY ref gen modes */
+	for (vty_ref_gen_mode_name = vty_ref_gen_mode_names; vty_ref_gen_mode_name->str; vty_ref_gen_mode_name++)
+		printf("                    %s: %s\n",
+		       vty_ref_gen_mode_name->str,
+		       get_value_string(vty_ref_gen_mode_desc, vty_ref_gen_mode_name->value));
+}
+
+static void handle_long_options(const char *prog_name, const int long_option)
+{
+	switch (long_option) {
+	case 1:
+		pfcp_tool_cmdline_config.vty_ref_gen_mode = get_string_value(vty_ref_gen_mode_names, optarg);
+		if (pfcp_tool_cmdline_config.vty_ref_gen_mode < 0) {
+			fprintf(stderr, "%s: Unknown VTY reference generation mode: '%s'\n", prog_name, optarg);
+			exit(2);
+		}
+		break;
+	case 2:
+		fprintf(stderr, "Generating the VTY reference in mode '%s' (%s)\n",
+			get_value_string(vty_ref_gen_mode_names, pfcp_tool_cmdline_config.vty_ref_gen_mode),
+			get_value_string(vty_ref_gen_mode_desc, pfcp_tool_cmdline_config.vty_ref_gen_mode));
+		vty_dump_xml_ref_mode(stdout, pfcp_tool_cmdline_config.vty_ref_gen_mode);
+		exit(0);
+	default:
+		fprintf(stderr, "%s: error parsing cmdline options\n", prog_name);
+		exit(2);
+	}
+}
+
+static void handle_options(int argc, char **argv)
+{
+	while (1) {
+		int option_index = 0, c;
+		static int long_option = 0;
+		static struct option long_options[] = {
+			{"help", 0, 0, 'h'},
+			{"daemonize", 0, 0, 'D'},
+			{"config-file", 1, 0, 'c'},
+			{"version", 0, 0, 'V' },
+			{"vty-ref-mode", 1, &long_option, 1},
+			{"vty-ref-xml", 0, &long_option, 2},
+			{0, 0, 0, 0}
+		};
+
+		c = getopt_long(argc, argv, "hDc:V", long_options, &option_index);
+		if (c == -1)
+			break;
+
+		switch (c) {
+		case 'h':
+			print_usage();
+			print_help();
+			exit(0);
+		case 0:
+			handle_long_options(argv[0], long_option);
+			break;
+		case 'D':
+			pfcp_tool_cmdline_config.daemonize = 1;
+			break;
+		case 'c':
+			pfcp_tool_cmdline_config.config_file = optarg;
+			break;
+		case 'V':
+			print_version(1);
+			exit(0);
+			break;
+		default:
+			/* catch unknown options *as well as* missing arguments. */
+			fprintf(stderr, "%s: Error in command line options. Exiting.\n", argv[0]);
+			exit(-1);
+		}
+	}
+
+	if (argc > optind) {
+		pfcp_tool_cmdline_config.command_file = argv[optind];
+		optind++;
+	}
+
+	if (argc > optind) {
+		fprintf(stderr, "%s: Unsupported positional arguments on command line\n", argv[optind]);
+		exit(2);
+	}
+}
+
+static void signal_handler(int signum)
+{
+	fprintf(stdout, "signal %u received\n", signum);
+
+	switch (signum) {
+	case SIGINT:
+	case SIGTERM:
+		LOGP(DLGLOBAL, LOGL_NOTICE, "Terminating due to signal %d\n", signum);
+		quit++;
+		break;
+	case SIGABRT:
+		osmo_generate_backtrace();
+		/* in case of abort, we want to obtain a talloc report and
+		 * then run default SIGABRT handler, who will generate coredump
+		 * and abort the process. abort() should do this for us after we
+		 * return, but program wouldn't exit if an external SIGABRT is
+		 * received.
+		 */
+		talloc_report(tall_vty_ctx, stderr);
+		talloc_report_full(tall_pfcp_tool_ctx, stderr);
+		signal(SIGABRT, SIG_DFL);
+		raise(SIGABRT);
+		break;
+	case SIGUSR1:
+		talloc_report(tall_vty_ctx, stderr);
+		talloc_report_full(tall_pfcp_tool_ctx, stderr);
+		break;
+	case SIGUSR2:
+		talloc_report_full(tall_vty_ctx, stderr);
+		break;
+	default:
+		break;
+	}
+}
+
+static const char * const osmo_pfcp_tool_copyright =
+	"OsmoPFCPTool - Osmocom Packet Forwarding Control Protocol tool for testing\r\n"
+	"Copyright (C) 2021-2022 by sysmocom - s.f.m.c. GmbH <info@sysmocom.de>\r\n"
+	"License AGPLv3+: GNU AGPL version 3 or later <http://gnu.org/licenses/agpl-3.0.html>\r\n"
+	"This is free software: you are free to change and redistribute it.\r\n"
+	"There is NO WARRANTY, to the extent permitted by law.\r\n";
+
+static struct vty_app_info pfcp_tool_vty_app_info = {
+	.name = "osmo-pfcp-tool",
+	.version = PACKAGE_VERSION,
+	.copyright = osmo_pfcp_tool_copyright,
+};
+
+static const struct log_info_cat pfcp_tool_default_categories[] = {
+};
+
+const struct log_info log_info = {
+	.cat = pfcp_tool_default_categories,
+	.num_cat = ARRAY_SIZE(pfcp_tool_default_categories),
+};
+
+int pfcp_tool_mainloop()
+{
+	log_reset_context();
+	osmo_select_main_ctx(0);
+
+	/* If the user hits Ctrl-C the third time, just terminate immediately. */
+	if (quit >= 3)
+		return 1;
+
+	/* Has SIGTERM been received (and not yet been handled)? */
+	if (quit && !osmo_select_shutdown_requested()) {
+		osmo_signal_dispatch(SS_L_GLOBAL, S_L_GLOBAL_SHUTDOWN, NULL);
+
+		/* Request write-only mode in osmo_select_main_ctx() */
+		osmo_select_shutdown_request();
+		/* continue the main select loop until all write queues are serviced. */
+	}
+	return 0;
+}
+
+int main(int argc, char **argv)
+{
+	int rc;
+
+	/* Track the use of talloc NULL memory contexts */
+	talloc_enable_null_tracking();
+
+	osmo_fsm_set_dealloc_ctx(OTC_SELECT);
+
+	tall_pfcp_tool_ctx = talloc_named_const(NULL, 1, "osmo-pfcp-tool");
+	pfcp_tool_vty_app_info.tall_ctx = tall_pfcp_tool_ctx;
+
+	msgb_talloc_ctx_init(tall_pfcp_tool_ctx, 0);
+	osmo_signal_talloc_ctx_init(tall_pfcp_tool_ctx);
+
+	osmo_init_logging2(tall_pfcp_tool_ctx, &log_info);
+	log_set_print_category_hex(osmo_stderr_target, 0);
+	log_set_print_category(osmo_stderr_target, 1);
+	log_set_print_level(osmo_stderr_target, 1);
+	log_set_print_filename2(osmo_stderr_target, LOG_FILENAME_BASENAME);
+	log_set_print_filename_pos(osmo_stderr_target, LOG_FILENAME_POS_LINE_END);
+	log_set_print_extended_timestamp(osmo_stderr_target, 1);
+
+	osmo_fsm_log_timeouts(true);
+	osmo_fsm_log_addr(true);
+
+	osmo_stats_init(tall_pfcp_tool_ctx);
+
+	g_pfcp_tool_alloc(tall_pfcp_tool_ctx);
+
+	/* For --version, vty_init() must be called before handling options */
+	vty_init(&pfcp_tool_vty_app_info);
+
+	ctrl_vty_init(tall_pfcp_tool_ctx);
+	logging_vty_add_cmds();
+	osmo_talloc_vty_add_cmds();
+	osmo_cpu_sched_vty_init(tall_pfcp_tool_ctx);
+	osmo_fsm_vty_add_cmds();
+	osmo_tdef_vty_groups_init(CONFIG_NODE, g_pfcp_tool_tdef_groups);
+
+	pfcp_tool_vty_init_cfg();
+
+	/* Parse options */
+	handle_options(argc, argv);
+
+	if (pfcp_tool_cmdline_config.config_file) {
+		rc = vty_read_config_file(pfcp_tool_cmdline_config.config_file, NULL);
+		if (rc < 0) {
+			LOGP(DLGLOBAL, LOGL_ERROR, "Failed to parse the config file: '%s'\n",
+			     pfcp_tool_cmdline_config.config_file);
+		}
+	}
+
+	/* start telnet, after reading config for vty_get_bind_addr() */
+	rc = telnet_init_dynif(tall_pfcp_tool_ctx, &g_pfcp_tool, vty_get_bind_addr(), OSMO_VTY_PORT_PFCP_TOOL);
+	if (rc < 0)
+		return 2;
+
+	/* start control interface, after reading config for ctrl_vty_get_bind_addr() */
+	g_pfcp_tool->ctrl = ctrl_interface_setup_dynip(g_pfcp_tool, ctrl_vty_get_bind_addr(), OSMO_CTRL_PORT_PFCP_TOOL, NULL);
+	if (!g_pfcp_tool->ctrl) {
+		fprintf(stderr, "Failed to initialize control interface. Exiting.\n");
+		return -1;
+	}
+
+	signal(SIGINT, &signal_handler);
+	signal(SIGTERM, &signal_handler);
+	signal(SIGABRT, &signal_handler);
+	signal(SIGUSR1, &signal_handler);
+	signal(SIGUSR2, &signal_handler);
+	osmo_init_ignore_signals();
+
+	if (pfcp_tool_cmdline_config.daemonize) {
+		rc = osmo_daemonize();
+		if (rc < 0) {
+			perror("Error during daemonize");
+			return 6;
+		}
+	}
+
+	pfcp_tool_mainloop();
+
+	pfcp_tool_vty_init_cmds();
+
+	if (pfcp_tool_cmdline_config.command_file) {
+		printf("Reading '%s'\n", pfcp_tool_cmdline_config.command_file);
+		rc = vty_read_config_file(pfcp_tool_cmdline_config.command_file, NULL);
+		if (rc < 0) {
+			LOGP(DLGLOBAL, LOGL_FATAL, "Failed to parse the command file: '%s'\n",
+			     pfcp_tool_cmdline_config.command_file);
+			return 1;
+		}
+		printf("Done reading '%s', waiting for retransmission queue...\n",
+		       pfcp_tool_cmdline_config.command_file);
+		do {
+			if (pfcp_tool_mainloop())
+				break;
+		} while (!llist_empty(&g_pfcp_tool->ep->retrans_queue));
+		printf("Done\n");
+	} else {
+		printf("Listening for commands on VTY...\n");
+		do {
+			if (pfcp_tool_mainloop())
+				break;
+		} while (!osmo_select_shutdown_done());
+	}
+
+	osmo_pfcp_endpoint_free(&g_pfcp_tool->ep);
+
+	log_fini();
+
+	/* Report the heap state of talloc contexts, then free, so both ASAN and Valgrind are happy... */
+	//talloc_report_full(tall_pfcp_tool_ctx, stderr);
+	talloc_free(tall_pfcp_tool_ctx);
+
+	//talloc_report_full(tall_vty_ctx, stderr);
+	talloc_free(tall_vty_ctx);
+
+	//talloc_report_full(NULL, stderr);
+	talloc_disable_null_tracking();
+	return 0;
+}

src/osmo-pfcp-tool/pfcp_tool.c

@@ -0,0 +1,176 @@
+/*
+ * (C) 2021-2022 by sysmocom - s.f.m.c. GmbH <info@sysmocom.de>
+ * All Rights Reserved.
+ *
+ * Author: Neels Janosch Hofmeyr <nhofmeyr@sysmocom.de>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include <osmocom/core/utils.h>
+#include <osmocom/core/talloc.h>
+
+#include <osmocom/pfcp/pfcp_endpoint.h>
+
+#include "pfcp_tool.h"
+
+struct g_pfcp_tool *g_pfcp_tool = NULL;
+
+struct osmo_tdef_group g_pfcp_tool_tdef_groups[] = {
+	{ .name = "pfcp", .tdefs = osmo_pfcp_tdefs, .desc = "PFCP" },
+	{}
+};
+
+void g_pfcp_tool_alloc(void *ctx)
+{
+	OSMO_ASSERT(g_pfcp_tool == NULL);
+	g_pfcp_tool = talloc_zero(ctx, struct g_pfcp_tool);
+
+	*g_pfcp_tool = (struct g_pfcp_tool){
+		.vty_cfg = {
+			.local_ip = talloc_strdup(g_pfcp_tool, "0.0.0.0"),
+			.local_port = OSMO_PFCP_PORT,
+		},
+	};
+
+	INIT_LLIST_HEAD(&g_pfcp_tool->peers);
+}
+
+struct pfcp_tool_peer *pfcp_tool_peer_find(const struct osmo_sockaddr *remote_addr)
+{
+	struct pfcp_tool_peer *peer;
+	llist_for_each_entry(peer, &g_pfcp_tool->peers, entry) {
+		if (osmo_sockaddr_cmp(&peer->remote_addr, remote_addr) == 0)
+			return peer;
+	}
+	return NULL;
+}
+
+struct pfcp_tool_peer *pfcp_tool_peer_find_or_create(const struct osmo_sockaddr *remote_addr)
+{
+	struct pfcp_tool_peer *peer = pfcp_tool_peer_find(remote_addr);
+	if (peer)
+		return peer;
+
+	peer = talloc_zero(g_pfcp_tool, struct pfcp_tool_peer);
+	peer->remote_addr = *remote_addr;
+	peer->next_seid_state = 0x1234567;
+	INIT_LLIST_HEAD(&peer->sessions);
+	llist_add(&peer->entry, &g_pfcp_tool->peers);
+	return peer;
+}
+
+struct pfcp_tool_session *pfcp_tool_session_find(struct pfcp_tool_peer *peer, uint64_t cp_seid)
+{
+	struct pfcp_tool_session *session;
+	llist_for_each_entry(session, &peer->sessions, entry) {
+		if (session->cp_seid == cp_seid)
+			return session;
+	}
+	return NULL;
+}
+
+struct pfcp_tool_session *pfcp_tool_session_find_or_create(struct pfcp_tool_peer *peer, uint64_t cp_seid,
+							   enum up_gtp_action_kind gtp_action)
+{
+	struct pfcp_tool_session *session = pfcp_tool_session_find(peer, cp_seid);
+	if (session)
+		return session;
+
+	session = talloc(peer, struct pfcp_tool_session);
+	*session = (struct pfcp_tool_session){
+		.peer = peer,
+		.cp_seid = cp_seid,
+		.gtp_action = gtp_action,
+	};
+	llist_add(&session->entry, &peer->sessions);
+	return session;
+}
+
+static void rx_assoc_setup_resp(struct osmo_pfcp_endpoint *ep, struct osmo_pfcp_msg *m)
+{
+	if (m->ies.assoc_setup_resp.up_function_features_present)
+		OSMO_LOG_PFCP_MSG(m, LOGL_NOTICE, "Associated. UP Peer features: %s\n",
+				  osmo_pfcp_bits_to_str_c(OTC_SELECT,
+							  m->ies.assoc_setup_resp.up_function_features.bits,
+							  osmo_pfcp_up_feature_strs));
+
+	if (m->ies.assoc_setup_resp.cp_function_features_present)
+		OSMO_LOG_PFCP_MSG(m, LOGL_NOTICE, "Associated. CP Peer features: %s\n",
+				  osmo_pfcp_bits_to_str_c(OTC_SELECT,
+							  m->ies.assoc_setup_resp.cp_function_features.bits,
+							  osmo_pfcp_cp_feature_strs));
+}
+
+static void rx_session_est_resp(struct osmo_pfcp_endpoint *ep, struct osmo_pfcp_msg *m)
+{
+	struct pfcp_tool_peer *peer;
+	struct pfcp_tool_session *session;
+	enum osmo_pfcp_cause *cause = osmo_pfcp_msg_cause(m);
+	if (!cause) {
+		OSMO_LOG_PFCP_MSG(m, LOGL_ERROR, "Session Establishment Response should contain a Cause\n");
+		return;
+	}
+	if (*cause != OSMO_PFCP_CAUSE_REQUEST_ACCEPTED) {
+		OSMO_LOG_PFCP_MSG(m, LOGL_ERROR, "Peer responds that Session Establishment failed\n");
+		return;
+	}
+	if (!m->h.seid_present) {
+		OSMO_LOG_PFCP_MSG(m, LOGL_ERROR, "Session Establishment Response should contain a SEID\n");
+		return;
+	}
+	if (!m->ies.session_est_resp.up_f_seid_present) {
+		OSMO_LOG_PFCP_MSG(m, LOGL_ERROR, "Session Establishment Response without UP F-SEID\n");
+		return;
+	}
+	peer = pfcp_tool_peer_find(&m->remote_addr);
+	if (!peer)
+		return;
+	session = pfcp_tool_session_find(peer, m->h.seid);
+	if (!session)
+		return;
+	session->up_f_seid = m->ies.session_est_resp.up_f_seid;
+}
+
+void pfcp_tool_rx_msg(struct osmo_pfcp_endpoint *ep, struct osmo_pfcp_msg *m)
+{
+	switch (m->h.message_type) {
+	case OSMO_PFCP_MSGT_ASSOC_SETUP_RESP:
+		rx_assoc_setup_resp(ep, m);
+		break;
+	case OSMO_PFCP_MSGT_SESSION_EST_RESP:
+		rx_session_est_resp(ep, m);
+		break;
+	default: break;
+	}
+}
+
+int peer_tx(struct pfcp_tool_peer *peer, struct osmo_pfcp_msg *m)
+{
+	int rc;
+	rc = osmo_pfcp_endpoint_tx(g_pfcp_tool->ep, m);
+	if (m->is_response)
+		peer->last_resp = *m;
+	else
+		peer->last_req = *m;
+	return rc;
+}
+
+uint64_t peer_new_seid(struct pfcp_tool_peer *peer)
+{
+	return peer->next_seid_state++;
+}

src/osmo-pfcp-tool/pfcp_tool.h

@@ -0,0 +1,106 @@
+/* Global definitions for osmo-pfcp-tool */
+/*
+ * (C) 2021-2022 by sysmocom - s.f.m.c. GmbH <info@sysmocom.de>
+ * All Rights Reserved.
+ *
+ * Author: Neels Janosch Hofmeyr <nhofmeyr@sysmocom.de>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#pragma once
+
+#include <osmocom/core/linuxlist.h>
+#include <osmocom/core/tdef.h>
+#include <osmocom/core/socket.h>
+#include <osmocom/core/sockaddr_str.h>
+
+#include <osmocom/pfcp/pfcp_msg.h>
+
+#include <osmocom/upf/up_gtp_action.h>
+
+struct osmo_tdef;
+struct ctrl_handle;
+
+extern struct osmo_tdef g_pfcp_tool_tdefs[];
+extern struct osmo_tdef_group g_pfcp_tool_tdef_groups[];
+
+struct pfcp_tool_peer {
+	struct llist_head entry;
+
+	struct osmo_sockaddr remote_addr;
+	struct osmo_pfcp_msg last_req;
+	struct osmo_pfcp_msg last_resp;
+
+	uint64_t next_seid_state;
+
+	struct llist_head sessions;
+};
+
+struct pfcp_tool_teid_pair {
+	uint32_t local;
+	uint32_t remote;
+};
+
+struct pfcp_tool_session {
+	struct llist_head entry;
+
+	enum up_gtp_action_kind gtp_action;
+
+	struct pfcp_tool_peer *peer;
+	uint64_t cp_seid;
+	struct osmo_pfcp_ie_f_seid up_f_seid;
+
+	struct {
+		struct pfcp_tool_teid_pair teid;
+		struct osmo_sockaddr_str gtp_ip;
+	} access;
+
+	struct {
+		struct pfcp_tool_teid_pair teid;
+		struct osmo_sockaddr_str gtp_ip;
+		struct osmo_sockaddr_str ue_addr;
+	} core;
+};
+
+struct g_pfcp_tool {
+	struct ctrl_handle *ctrl;
+
+	struct {
+		char *local_ip;
+		uint16_t local_port;
+	} vty_cfg;
+
+	struct osmo_pfcp_endpoint *ep;
+	struct llist_head peers;
+};
+
+extern struct g_pfcp_tool *g_pfcp_tool;
+
+void g_pfcp_tool_alloc(void *ctx);
+void pfcp_tool_vty_init_cfg();
+void pfcp_tool_vty_init_cmds();
+
+int pfcp_tool_mainloop();
+
+struct pfcp_tool_peer *pfcp_tool_peer_find_or_create(const struct osmo_sockaddr *remote_addr);
+struct pfcp_tool_session *pfcp_tool_session_find_or_create(struct pfcp_tool_peer *peer, uint64_t cp_seid,
+							   enum up_gtp_action_kind kind);
+void pfcp_tool_rx_msg(struct osmo_pfcp_endpoint *ep, struct osmo_pfcp_msg *m);
+
+int peer_tx(struct pfcp_tool_peer *peer, struct osmo_pfcp_msg *m);
+uint64_t peer_new_seid(struct pfcp_tool_peer *peer);

src/osmo-pfcp-tool/pfcp_tool_vty.c

@@ -0,0 +1,785 @@
+/* osmo-pfcp-tool interface to quagga VTY */
+/*
+ * (C) 2021-2022 by sysmocom - s.f.m.c. GmbH <info@sysmocom.de>
+ * All Rights Reserved.
+ *
+ * Author: Neels Janosch Hofmeyr <nhofmeyr@sysmocom.de>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include <stdlib.h>
+#include <unistd.h>
+
+#include <osmocom/core/sockaddr_str.h>
+#include <osmocom/core/socket.h>
+
+#include <osmocom/pfcp/pfcp_endpoint.h>
+#include <osmocom/pfcp/pfcp_msg.h>
+
+#include <osmocom/vty/vty.h>
+#include <osmocom/vty/command.h>
+
+#include "pfcp_tool.h"
+
+enum pfcp_tool_vty_node {
+	PEER_NODE = _LAST_OSMOVTY_NODE + 1,
+	SESSION_NODE,
+};
+
+DEFUN(c_local_addr, c_local_addr_cmd,
+      "local-addr IP_ADDR",
+      "Set the local IP address to bind on for PFCP; see also 'listen'\n"
+      "IP address\n")
+{
+	if (g_pfcp_tool->ep != NULL) {
+		vty_out(vty, "Already listening on %s%s",
+			osmo_sockaddr_to_str_c(OTC_SELECT, &g_pfcp_tool->ep->cfg.local_addr),
+			VTY_NEWLINE);
+		return CMD_WARNING;
+	}
+
+	osmo_talloc_replace_string(g_pfcp_tool, &g_pfcp_tool->vty_cfg.local_ip, argv[0]);
+
+	return CMD_SUCCESS;
+}
+
+DEFUN(c_listen, c_listen_cmd,
+      "listen",
+      "Bind local PFCP port and listen; see also 'local-addr'\n")
+{
+	struct osmo_sockaddr_str local_addr;
+	int rc;
+
+	OSMO_ASSERT(g_pfcp_tool);
+	if (g_pfcp_tool->ep != NULL) {
+		vty_out(vty, "Already listening on %s%s",
+			osmo_sockaddr_to_str_c(OTC_SELECT, &g_pfcp_tool->ep->cfg.local_addr),
+			VTY_NEWLINE);
+		return CMD_WARNING;
+	}
+
+	g_pfcp_tool->ep = osmo_pfcp_endpoint_create(g_pfcp_tool, g_pfcp_tool);
+	if (!g_pfcp_tool->ep) {
+		vty_out(vty, "Failed to allocate PFCP endpoint.%s", VTY_NEWLINE);
+		return CMD_WARNING;
+	}
+	g_pfcp_tool->ep->rx_msg = pfcp_tool_rx_msg;
+	g_pfcp_tool->ep->seq_nr_state = rand();
+
+	/* Translate address string from VTY config to osmo_sockaddr: first read into osmo_sockaddr_str, then write to
+	 * osmo_sockaddr. */
+	osmo_sockaddr_str_from_str(&local_addr, g_pfcp_tool->vty_cfg.local_ip,
+				   g_pfcp_tool->vty_cfg.local_port);
+	osmo_sockaddr_str_to_sockaddr(&local_addr, &g_pfcp_tool->ep->cfg.local_addr.u.sas);
+
+	/* Store this address as the local PFCP Node Id */
+	osmo_pfcp_ie_node_id_from_osmo_sockaddr(&g_pfcp_tool->ep->cfg.local_node_id, &g_pfcp_tool->ep->cfg.local_addr);
+
+	rc = osmo_pfcp_endpoint_bind(g_pfcp_tool->ep);
+	if (rc) {
+		vty_out(vty, "Failed to bind PFCP endpoint on %s: %s%s\n",
+			osmo_sockaddr_to_str_c(OTC_SELECT, &g_pfcp_tool->ep->cfg.local_addr), strerror(rc),
+			VTY_NEWLINE);
+		return CMD_WARNING;
+	}
+	return CMD_SUCCESS;
+}
+
+DEFUN(c_sleep, c_sleep_cmd,
+	"sleep <0-999999> [<0-999>]",
+	"Let some time pass\n"
+	"Seconds to wait\n")
+{
+	int secs = atoi(argv[0]);
+	int msecs = 0;
+	struct osmo_timer_list t = {};
+	if (argc > 1)
+		msecs = atoi(argv[1]);
+
+	vty_out(vty, "zzZ %d.%03ds...%s", secs, msecs, VTY_NEWLINE);
+	vty_flush(vty);
+
+	osmo_timer_setup(&t, NULL, NULL);
+	osmo_timer_schedule(&t, secs, msecs * 1000);
+
+	/* Still operate the message pump while waiting for time to pass */
+	while (t.active && !osmo_select_shutdown_done()) {
+		if (pfcp_tool_mainloop())
+			break;
+	}
+
+	osmo_timer_del(&t);
+	vty_out(vty, "...zzZ %d.%03ds%s", secs, msecs, VTY_NEWLINE);
+	vty_flush(vty);
+	return CMD_SUCCESS;
+}
+
+static struct cmd_node peer_node = {
+	PEER_NODE,
+	"%s(peer)# ",
+	1,
+};
+
+DEFUN(peer, peer_cmd,
+      "pfcp-peer REMOTE_ADDR",
+      "Enter the 'peer' node for the given remote address\n"
+      "Remote PFCP peer's IP address\n")
+{
+	struct pfcp_tool_peer *peer;
+	struct osmo_sockaddr_str remote_addr_str;
+	struct osmo_sockaddr remote_addr;
+
+	osmo_sockaddr_str_from_str(&remote_addr_str, argv[0], OSMO_PFCP_PORT);
+	osmo_sockaddr_str_to_sockaddr(&remote_addr_str, (struct sockaddr_storage*)&remote_addr);
+
+	peer = pfcp_tool_peer_find_or_create(&remote_addr);
+
+	vty->index = peer;
+	vty->node = PEER_NODE;
+
+	return CMD_SUCCESS;
+}
+
+#define TX_STR "Send a PFCP message to a peer\n"
+
+DEFUN(peer_tx_heartbeat, peer_tx_heartbeat_cmd,
+      "tx heartbeat",
+      TX_STR "Send a Heartbeat Request\n")
+{
+	struct pfcp_tool_peer *peer = vty->index;
+	int rc;
+
+	if (!g_pfcp_tool->ep) {
+		vty_out(vty, "Endpoint not configured%s", VTY_NEWLINE);
+		return CMD_WARNING;
+	}
+
+	vty_out(vty, "Tx Heartbeat Request to %s%s",
+		osmo_sockaddr_to_str_c(OTC_SELECT, &peer->remote_addr), VTY_NEWLINE);
+
+	rc = osmo_pfcp_endpoint_tx_heartbeat_req(g_pfcp_tool->ep, &peer->remote_addr);
+	if (rc) {
+		vty_out(vty, "Failed to transmit: %s%s", strerror(-rc), VTY_NEWLINE);
+		return CMD_WARNING;
+	}
+	return CMD_SUCCESS;
+}
+
+DEFUN(peer_tx_assoc_setup_req, peer_tx_assoc_setup_req_cmd,
+      "tx assoc-setup-req",
+      TX_STR "Send an Association Setup Request\n")
+{
+	struct pfcp_tool_peer *peer = vty->index;
+	int rc;
+	struct osmo_pfcp_msg *m;
+
+	if (!g_pfcp_tool->ep) {
+		vty_out(vty, "Endpoint not configured%s", VTY_NEWLINE);
+		return CMD_WARNING;
+	}
+
+	m = osmo_pfcp_msg_alloc_tx(OTC_SELECT, &peer->remote_addr, &g_pfcp_tool->ep->cfg.local_node_id, NULL,
+				   OSMO_PFCP_MSGT_ASSOC_SETUP_REQ);
+	m->ies.assoc_setup_req.recovery_time_stamp = g_pfcp_tool->ep->recovery_time_stamp;
+
+	m->ies.assoc_setup_req.cp_function_features_present = true;
+	osmo_pfcp_bits_set(m->ies.assoc_setup_req.cp_function_features.bits, OSMO_PFCP_CP_FEAT_BUNDL, true);
+
+	rc = peer_tx(peer, m);
+	if (rc) {
+		vty_out(vty, "Failed to transmit: %s%s", strerror(-rc), VTY_NEWLINE);
+		return CMD_WARNING;
+	}
+	return CMD_SUCCESS;
+}
+
+DEFUN(peer_retrans_req, peer_retrans_req_cmd,
+      "retrans (req|resp)",
+      "Retransmit the last sent message\n" "Retransmit the last sent PFCP Request\n"
+      "Retransmit the last sent PFCP Response\n")
+{
+	struct pfcp_tool_peer *peer = vty->index;
+	int rc;
+	struct osmo_pfcp_msg *m;
+
+	if (!g_pfcp_tool->ep) {
+		vty_out(vty, "Endpoint not configured%s", VTY_NEWLINE);
+		return CMD_WARNING;
+	}
+
+	m = osmo_pfcp_msg_alloc_tx(OTC_SELECT, &peer->remote_addr, &g_pfcp_tool->ep->cfg.local_node_id, NULL, 0);
+	if (strcmp(argv[0], "req") == 0)
+		*m = peer->last_req;
+	else
+		*m = peer->last_resp;
+
+	OSMO_LOG_PFCP_MSG(m, LOGL_DEBUG, "retrans %s\n", argv[0]);
+
+	rc = osmo_pfcp_endpoint_tx_data(g_pfcp_tool->ep, m);
+	if (rc) {
+		vty_out(vty, "Failed to transmit: %s%s", strerror(-rc), VTY_NEWLINE);
+		return CMD_WARNING;
+	}
+	return CMD_SUCCESS;
+}
+
+static struct cmd_node session_node = {
+	SESSION_NODE,
+	"%s(session)# ",
+	1,
+};
+
+DEFUN(session, session_cmd,
+      "session [(endecaps|tunmap)] [<0-18446744073709551615>]",
+      "Enter the 'session' node for the given SEID\n"
+      "Set up GTP tunnel encapsulation/decapsulation (default)\n"
+      "Set up GTP tunnel mapping\n"
+      "local Session Endpoint ID\n")
+{
+	struct pfcp_tool_peer *peer = vty->index;
+	struct pfcp_tool_session *session;
+	enum up_gtp_action_kind gtp_action = UP_GTP_U_ENDECAPS;
+
+	if (argc > 0 && !strcmp(argv[0], "tunmap"))
+		gtp_action = UP_GTP_U_TUNMAP;
+
+	if (argc > 1)
+		session = pfcp_tool_session_find_or_create(peer, atoll(argv[1]), gtp_action);
+	else
+		session = pfcp_tool_session_find_or_create(peer, peer_new_seid(peer), gtp_action);
+
+	vty->index = session;
+	vty->node = SESSION_NODE;
+
+	return CMD_SUCCESS;
+}
+
+DEFUN(s_ue, s_ue_cmd,
+      "ue ip A.B.C.D",
+      "Setup the UE as it appears towards the Core network in plain IP traffic\n"
+      "IP address assigned to the UE\n")
+{
+	struct pfcp_tool_session *session = vty->index;
+	if (osmo_sockaddr_str_from_str2(&session->core.ue_addr, argv[0])) {
+		vty_out(vty, "Error setting UE IP address%s", VTY_NEWLINE);
+		return CMD_WARNING;
+	}
+	return CMD_SUCCESS;
+}
+
+DEFUN(s_teid, s_teid_cmd,
+      "gtp (access|core) teid local <0-4294967295> remote <0-4294967295>",
+      "Setup TEID used in GTP\n"
+      "Set the TEIDs towards the ACCESS network (towards the radio network and the actual UE)\n"
+      "Set the TEIDs towards the CORE network (towards the internet)\n"
+      "Local TEID, which the UPF expects to see in incoming GTP packets\n"
+      "Local TEID, when 0 tell the UPF to choose (PFCP: FAR F-TEID: CHOOSE=1)\n"
+      "Remote TEID, which the UPF sends out in GTP packets\n"
+      "Remote TEID, which the GTP peer has assigned for itself\n")
+{
+	struct pfcp_tool_session *session = vty->index;
+	struct pfcp_tool_teid_pair *dst;
+	if (!strcmp(argv[0], "access"))
+		dst = &session->access.teid;
+	else
+		dst = &session->core.teid;
+	*dst = (struct pfcp_tool_teid_pair){
+		.local = atoi(argv[1]),
+		.remote = atoi(argv[2]),
+	};
+	return CMD_SUCCESS;
+}
+
+DEFUN(s_gtp, s_gtp_cmd,
+      "gtp (access|core) ip A.B.C.D",
+      "Setup GTP peer\n"
+      "Set the GTP peer towards the ACCESS network (towards the radio network and the actual UE)\n"
+      "Set the GTP peer towards the CORE network (towards the internet)\n"
+      "Set the GTP peer IP address, where to send GTP packets to / receive GTP packets from\n"
+      "GTP peer IP address\n")
+{
+	struct pfcp_tool_session *session = vty->index;
+	struct osmo_sockaddr_str *dst;
+	if (!strcmp(argv[0], "access"))
+		dst = &session->access.gtp_ip;
+	else
+		dst = &session->core.gtp_ip;
+	if (osmo_sockaddr_str_from_str2(dst, argv[1])) {
+		vty_out(vty, "Error setting GTP IP address%s", VTY_NEWLINE);
+		return CMD_WARNING;
+	}
+	return CMD_SUCCESS;
+}
+
+int session_endecaps_tx_est_req(struct vty *vty, const char **argv, int argc)
+{
+	struct pfcp_tool_session *session = vty->index;
+	struct pfcp_tool_peer *peer = session->peer;
+	int rc;
+	struct osmo_pfcp_msg *m;
+	struct osmo_pfcp_ie_f_teid f_teid_access_local;
+	struct osmo_pfcp_ie_outer_header_creation ohc_access;
+	struct osmo_pfcp_ie_apply_action aa = {};
+	struct osmo_sockaddr ue_addr;
+	struct osmo_pfcp_ie_f_seid cp_f_seid;
+
+	if (!g_pfcp_tool->ep) {
+		vty_out(vty, "Endpoint not configured%s", VTY_NEWLINE);
+		return CMD_WARNING;
+	}
+
+	if (argc > 0 && !strcmp("drop", argv[0]))
+		osmo_pfcp_bits_set(aa.bits, OSMO_PFCP_APPLY_ACTION_DROP, true);
+	else
+		osmo_pfcp_bits_set(aa.bits, OSMO_PFCP_APPLY_ACTION_FORW, true);
+
+	if (osmo_sockaddr_str_to_sockaddr(&session->core.ue_addr, &ue_addr.u.sas)) {
+		vty_out(vty, "Error in UE IP%s", VTY_NEWLINE);
+		return CMD_WARNING;
+	}
+
+	if (session->access.teid.local == 0) {
+		f_teid_access_local = (struct osmo_pfcp_ie_f_teid){
+			.choose_flag = true,
+			.choose = {
+				.ipv4_addr = true,
+			},
+		};
+	} else {
+		f_teid_access_local = (struct osmo_pfcp_ie_f_teid){
+			.fixed = {
+				.teid = session->access.teid.local,
+				.ip_addr = {
+					.v4_present = true,
+					.v4 = g_pfcp_tool->ep->cfg.local_addr,
+				},
+			},
+		};
+		if (osmo_sockaddr_str_to_sockaddr(&session->access.gtp_ip, &f_teid_access_local.fixed.ip_addr.v4.u.sas)) {
+			vty_out(vty, "Error in GTP IP towards Access%s", VTY_NEWLINE);
+			return CMD_WARNING;
+		}
+	}
+
+	ohc_access = (struct osmo_pfcp_ie_outer_header_creation){
+		.teid_present = true,
+		.teid = session->access.teid.remote,
+		.ip_addr.v4_present = true,
+	};
+	osmo_pfcp_bits_set(ohc_access.desc_bits, OSMO_PFCP_OUTER_HEADER_CREATION_GTP_U_UDP_IPV4, true);
+	if (osmo_sockaddr_str_to_sockaddr(&session->access.gtp_ip, &ohc_access.ip_addr.v4.u.sas)) {
+		vty_out(vty, "Error in GTP IP towards Access%s", VTY_NEWLINE);
+		return CMD_WARNING;
+	}
+
+	cp_f_seid = (struct osmo_pfcp_ie_f_seid){
+		.seid = session->cp_seid,
+	};
+	osmo_pfcp_ip_addrs_set(&cp_f_seid.ip_addr, &g_pfcp_tool->ep->cfg.local_addr);
+
+	m = osmo_pfcp_msg_alloc_tx(OTC_SELECT, &peer->remote_addr, &g_pfcp_tool->ep->cfg.local_node_id, NULL,
+				   OSMO_PFCP_MSGT_SESSION_EST_REQ);
+	m->h.seid_present = true;
+	/* the UPF has yet to assign a SEID for itself, no matter what SEID we (the CPF) use for this session */
+	m->h.seid = 0;
+	/* GTP encapsulation decapsulation: remove header from ACCESS to CORE, add header from CORE towards ACCESS */
+	m->ies.session_est_req = (struct osmo_pfcp_msg_session_est_req){
+		.node_id = m->ies.session_est_req.node_id,
+		.cp_f_seid_present = true,
+		.cp_f_seid = cp_f_seid,
+		.create_pdr_count = 2,
+		.create_pdr = {
+			{
+				.pdr_id = 1,
+				.precedence = 255,
+				.pdi = {
+					.source_iface = OSMO_PFCP_SOURCE_IFACE_CORE,
+					.ue_ip_address_present = true,
+					.ue_ip_address = {
+						.ip_is_destination = true,
+						.ip_addr = {
+							.v4_present = true,
+							.v4 = ue_addr,
+						},
+					},
+				},
+				.far_id_present = true,
+				.far_id = 1,
+			},
+			{
+				.pdr_id = 2,
+				.precedence = 255,
+				.pdi = {
+					.source_iface = OSMO_PFCP_SOURCE_IFACE_ACCESS,
+					.local_f_teid_present = true,
+					.local_f_teid = f_teid_access_local,
+				},
+				.outer_header_removal_present = true,
+				.outer_header_removal = {
+					.desc = OSMO_PFCP_OUTER_HEADER_REMOVAL_GTP_U_UDP_IPV4,
+				},
+				.far_id_present = true,
+				.far_id = 2,
+			},
+		},
+		.create_far_count = 2,
+		.create_far = {
+			{
+				.far_id = 1,
+				.forw_params_present = true,
+				.forw_params = {
+					.destination_iface = OSMO_PFCP_DEST_IFACE_ACCESS,
+					.outer_header_creation_present = true,
+					.outer_header_creation = ohc_access,
+				},
+				.apply_action = aa,
+			},
+			{
+				.far_id = 2,
+				.forw_params_present = true,
+				.forw_params = {
+					.destination_iface = OSMO_PFCP_DEST_IFACE_CORE,
+				},
+				.apply_action = aa,
+			},
+		},
+	};
+
+	rc = peer_tx(peer, m);
+	if (rc) {
+		vty_out(vty, "Failed to transmit: %s%s", strerror(-rc), VTY_NEWLINE);
+		return CMD_WARNING;
+	}
+	return CMD_SUCCESS;
+}
+
+int session_tunmap_tx_est_req(struct vty *vty, const char **argv, int argc)
+{
+	struct pfcp_tool_session *session = vty->index;
+	struct pfcp_tool_peer *peer = session->peer;
+	int rc;
+	struct osmo_pfcp_msg *m;
+
+	struct osmo_pfcp_ie_f_seid cp_f_seid;
+
+	struct osmo_pfcp_ie_f_teid f_teid_access_local;
+	struct osmo_pfcp_ie_outer_header_creation ohc_access;
+
+	struct osmo_pfcp_ie_f_teid f_teid_core_local;
+	struct osmo_pfcp_ie_outer_header_creation ohc_core;
+
+	struct osmo_pfcp_ie_apply_action aa = {};
+
+	if (!g_pfcp_tool->ep) {
+		vty_out(vty, "Endpoint not configured%s", VTY_NEWLINE);
+		return CMD_WARNING;
+	}
+
+	if (argc > 0 && !strcmp("drop", argv[0]))
+		osmo_pfcp_bits_set(aa.bits, OSMO_PFCP_APPLY_ACTION_DROP, true);
+	else
+		osmo_pfcp_bits_set(aa.bits, OSMO_PFCP_APPLY_ACTION_FORW, true);
+
+	if (session->access.teid.local == 0) {
+		f_teid_access_local = (struct osmo_pfcp_ie_f_teid){
+			.choose_flag = true,
+			.choose = {
+				.ipv4_addr = true,
+			},
+		};
+	} else {
+		f_teid_access_local = (struct osmo_pfcp_ie_f_teid){
+			.fixed = {
+				.teid = session->access.teid.local,
+				.ip_addr = {
+					.v4_present = true,
+					.v4 = g_pfcp_tool->ep->cfg.local_addr,
+				},
+			},
+		};
+		if (osmo_sockaddr_str_to_sockaddr(&session->access.gtp_ip, &f_teid_access_local.fixed.ip_addr.v4.u.sas)) {
+			vty_out(vty, "Error in GTP IP towards Access%s", VTY_NEWLINE);
+			return CMD_WARNING;
+		}
+	}
+
+	ohc_access = (struct osmo_pfcp_ie_outer_header_creation){
+		.teid_present = true,
+		.teid = session->access.teid.remote,
+		.ip_addr.v4_present = true,
+	};
+	osmo_pfcp_bits_set(ohc_access.desc_bits, OSMO_PFCP_OUTER_HEADER_CREATION_GTP_U_UDP_IPV4, true);
+	if (osmo_sockaddr_str_to_sockaddr(&session->access.gtp_ip, &ohc_access.ip_addr.v4.u.sas)) {
+		vty_out(vty, "Error in GTP IP towards Access%s", VTY_NEWLINE);
+		return CMD_WARNING;
+	}
+
+	if (session->core.teid.local == 0) {
+		f_teid_core_local = (struct osmo_pfcp_ie_f_teid){
+			.choose_flag = true,
+			.choose = {
+				.ipv4_addr = true,
+			},
+		};
+	} else {
+		f_teid_core_local = (struct osmo_pfcp_ie_f_teid){
+			.fixed = {
+				.teid = session->core.teid.local,
+				.ip_addr = {
+					.v4_present = true,
+					.v4 = g_pfcp_tool->ep->cfg.local_addr,
+				},
+			},
+		};
+		if (osmo_sockaddr_str_to_sockaddr(&session->core.gtp_ip, &f_teid_core_local.fixed.ip_addr.v4.u.sas)) {
+			vty_out(vty, "Error in GTP IP towards Core%s", VTY_NEWLINE);
+			return CMD_WARNING;
+		}
+	}
+	ohc_core = (struct osmo_pfcp_ie_outer_header_creation){
+		.teid_present = true,
+		.teid = session->core.teid.remote,
+		.ip_addr.v4_present = true,
+	};
+	osmo_pfcp_bits_set(ohc_core.desc_bits, OSMO_PFCP_OUTER_HEADER_CREATION_GTP_U_UDP_IPV4, true);
+	if (osmo_sockaddr_str_to_sockaddr(&session->core.gtp_ip, &ohc_core.ip_addr.v4.u.sas)) {
+		vty_out(vty, "Error in GTP IP towards Core%s", VTY_NEWLINE);
+		return CMD_WARNING;
+	}
+
+	cp_f_seid = (struct osmo_pfcp_ie_f_seid){
+		.seid = session->cp_seid,
+	};
+	osmo_pfcp_ip_addrs_set(&cp_f_seid.ip_addr, &g_pfcp_tool->ep->cfg.local_addr);
+
+	m = osmo_pfcp_msg_alloc_tx(OTC_SELECT, &peer->remote_addr, &g_pfcp_tool->ep->cfg.local_node_id, NULL,
+				   OSMO_PFCP_MSGT_SESSION_EST_REQ);
+	m->h.seid_present = true;
+	m->h.seid = 0;
+	/* GTP tunmap: remove header from both directions, and add header in both directions */
+	m->ies.session_est_req = (struct osmo_pfcp_msg_session_est_req){
+		.node_id = m->ies.session_est_req.node_id,
+		.cp_f_seid_present = true,
+		.cp_f_seid = cp_f_seid,
+		.create_pdr_count = 2,
+		.create_pdr = {
+			{
+				.pdr_id = 1,
+				.precedence = 255,
+				.pdi = {
+					.source_iface = OSMO_PFCP_SOURCE_IFACE_CORE,
+					.local_f_teid_present = true,
+					.local_f_teid = f_teid_core_local,
+				},
+				.outer_header_removal_present = true,
+				.outer_header_removal = {
+					.desc = OSMO_PFCP_OUTER_HEADER_REMOVAL_GTP_U_UDP_IPV4,
+				},
+				.far_id_present = true,
+				.far_id = 1,
+			},
+			{
+				.pdr_id = 2,
+				.precedence = 255,
+				.pdi = {
+					.source_iface = OSMO_PFCP_SOURCE_IFACE_ACCESS,
+					.local_f_teid_present = true,
+					.local_f_teid = f_teid_access_local,
+				},
+				.outer_header_removal_present = true,
+				.outer_header_removal = {
+					.desc = OSMO_PFCP_OUTER_HEADER_REMOVAL_GTP_U_UDP_IPV4,
+				},
+				.far_id_present = true,
+				.far_id = 2,
+			},
+		},
+		.create_far_count = 2,
+		.create_far = {
+			{
+				.far_id = 1,
+				.forw_params_present = true,
+				.forw_params = {
+					.destination_iface = OSMO_PFCP_DEST_IFACE_ACCESS,
+					.outer_header_creation_present = true,
+					.outer_header_creation = ohc_access,
+				},
+				.apply_action = aa,
+			},
+			{
+				.far_id = 2,
+				.forw_params_present = true,
+				.forw_params = {
+					.destination_iface = OSMO_PFCP_DEST_IFACE_CORE,
+					.outer_header_creation_present = true,
+					.outer_header_creation = ohc_core,
+				},
+				.apply_action = aa,
+			},
+		},
+	};
+
+	rc = peer_tx(peer, m);
+	if (rc) {
+		vty_out(vty, "Failed to transmit: %s%s", strerror(-rc), VTY_NEWLINE);
+		return CMD_WARNING;
+	}
+	return CMD_SUCCESS;
+}
+
+DEFUN(session_tx_est_req, session_tx_est_req_cmd,
+      "tx session-est-req [(forw|drop)]",
+      TX_STR "Send a Session Establishment Request\n"
+      "Set FAR to FORW = 1 (default)\n"
+      "Set FAR to DROP = 1\n")
+{
+	struct pfcp_tool_session *session = vty->index;
+	switch (session->gtp_action) {
+	case UP_GTP_U_ENDECAPS:
+		return session_endecaps_tx_est_req(vty, argv, argc);
+	case UP_GTP_U_TUNMAP:
+		return session_tunmap_tx_est_req(vty, argv, argc);
+	default:
+		vty_out(vty, "unknown gtp action%s", VTY_NEWLINE);
+		return CMD_WARNING;
+	}
+}
+
+DEFUN(session_tx_mod_req, session_tx_mod_req_cmd,
+      "tx session-mod-req far [(forw|drop)]",
+      TX_STR "Send a Session Modification Request\n"
+      "Set FAR to FORW = 1\n"
+      "Set FAR to DROP = 1\n")
+{
+	struct pfcp_tool_session *session = vty->index;
+	struct pfcp_tool_peer *peer = session->peer;
+	int rc;
+	struct osmo_pfcp_msg *m;
+	struct osmo_pfcp_ie_apply_action aa = {};
+	struct osmo_pfcp_ie_f_seid cp_f_seid;
+
+	if (!g_pfcp_tool->ep) {
+		vty_out(vty, "Endpoint not configured%s", VTY_NEWLINE);
+		return CMD_WARNING;
+	}
+
+	if (argc > 0 && !strcmp("drop", argv[0]))
+		osmo_pfcp_bits_set(aa.bits, OSMO_PFCP_APPLY_ACTION_DROP, true);
+	else
+		osmo_pfcp_bits_set(aa.bits, OSMO_PFCP_APPLY_ACTION_FORW, true);
+
+	cp_f_seid = (struct osmo_pfcp_ie_f_seid){
+		.seid = session->cp_seid,
+	};
+	osmo_pfcp_ip_addrs_set(&cp_f_seid.ip_addr, &g_pfcp_tool->ep->cfg.local_addr);
+
+	m = osmo_pfcp_msg_alloc_tx(OTC_SELECT, &peer->remote_addr, &g_pfcp_tool->ep->cfg.local_node_id, NULL,
+				   OSMO_PFCP_MSGT_SESSION_MOD_REQ);
+	m->h.seid_present = true;
+	m->h.seid = session->up_f_seid.seid;
+	m->ies.session_mod_req = (struct osmo_pfcp_msg_session_mod_req){
+		.cp_f_seid_present = true,
+		.cp_f_seid = cp_f_seid,
+		.upd_far_count = 2,
+		.upd_far = {
+			{
+				.far_id = 1,
+				.apply_action_present = true,
+				.apply_action = aa,
+			},
+			{
+				.far_id = 2,
+				.apply_action_present = true,
+				.apply_action = aa,
+			},
+		},
+	};
+
+	rc = peer_tx(peer, m);
+	if (rc) {
+		vty_out(vty, "Failed to transmit: %s%s", strerror(-rc), VTY_NEWLINE);
+		return CMD_WARNING;
+	}
+	return CMD_SUCCESS;
+}
+
+DEFUN(session_tx_del_req, session_tx_del_req_cmd,
+      "tx session-del-req",
+      TX_STR "Send a Session Deletion Request\n")
+{
+	struct pfcp_tool_session *session = vty->index;
+	struct pfcp_tool_peer *peer = session->peer;
+	int rc;
+	struct osmo_pfcp_msg *m;
+
+	if (!g_pfcp_tool->ep) {
+		vty_out(vty, "Endpoint not configured%s", VTY_NEWLINE);
+		return CMD_WARNING;
+	}
+
+	m = osmo_pfcp_msg_alloc_tx(OTC_SELECT, &peer->remote_addr, &g_pfcp_tool->ep->cfg.local_node_id, NULL,
+				   OSMO_PFCP_MSGT_SESSION_DEL_REQ);
+	m->h.seid_present = true;
+	m->h.seid = session->up_f_seid.seid;
+
+	rc = peer_tx(peer, m);
+	if (rc) {
+		vty_out(vty, "Failed to transmit: %s%s", strerror(-rc), VTY_NEWLINE);
+		return CMD_WARNING;
+	}
+	return CMD_SUCCESS;
+}
+
+static void install_ve_and_config(struct cmd_element *cmd)
+{
+	install_element_ve(cmd);
+	install_element(CONFIG_NODE, cmd);
+}
+
+void pfcp_tool_vty_init_cfg()
+{
+	OSMO_ASSERT(g_pfcp_tool != NULL);
+
+	install_ve_and_config(&c_local_addr_cmd);
+	install_ve_and_config(&c_listen_cmd);
+}
+
+void pfcp_tool_vty_init_cmds()
+{
+	OSMO_ASSERT(g_pfcp_tool != NULL);
+
+	install_ve_and_config(&c_sleep_cmd);
+
+	install_ve_and_config(&peer_cmd);
+	install_node(&peer_node, NULL);
+
+	install_element(PEER_NODE, &c_sleep_cmd);
+	install_element(PEER_NODE, &peer_tx_heartbeat_cmd);
+	install_element(PEER_NODE, &peer_tx_assoc_setup_req_cmd);
+	install_element(PEER_NODE, &peer_retrans_req_cmd);
+
+	install_element(PEER_NODE, &session_cmd);
+	install_node(&session_node, NULL);
+	install_element(SESSION_NODE, &c_sleep_cmd);
+	install_element(SESSION_NODE, &session_tx_est_req_cmd);
+	install_element(SESSION_NODE, &session_tx_mod_req_cmd);
+	install_element(SESSION_NODE, &session_tx_del_req_cmd);
+	install_element(SESSION_NODE, &s_ue_cmd);
+	install_element(SESSION_NODE, &s_gtp_cmd);
+	install_element(SESSION_NODE, &s_teid_cmd);
+}