15 Jan
2014
15 Jan
'14
2 p.m.
So far, a single dummy packet has been sent immediately after the
reception of a MDCX message. There is no dedicated keep alive
mechanism (it just worked because the audio from the MS has always
been forwarded to the NAT until the 'mgcp: Set output_enabled flags
based on the MGCP mode' patch).
This patch adds explicit, timer based keep alive handling that can be
enable per trunk. A VTY command 'rtp keep-alive' command is added for
configuration which can be used to set the interval in seconds, to
send a single packet after the reception of a CRCX/MDCX when RTP data
from the net is expected ('once'), or to disable the feature
completely ('no rtp keep-alive'). In 'send-recv' connections, only
the initial packet is sent if enabled (even when an interval has been
configured). The default is 'once'.
Note that this removes the mgcp_change_cb() from mgcp_main.c.
Sponsored-by: On-Waves ehf
---
openbsc/include/openbsc/mgcp.h | 9 ++++
openbsc/src/libmgcp/mgcp_protocol.c | 43 ++++++++++++++++
openbsc/src/libmgcp/mgcp_vty.c | 91 +++++++++++++++++++++++++++++++++
openbsc/src/osmo-bsc_mgcp/mgcp_main.c | 10 ----
openbsc/tests/mgcp/mgcp_test.ok | 6 +++
5 files changed, 149 insertions(+), 10 deletions(-)
diff --git a/openbsc/include/openbsc/mgcp.h b/openbsc/include/openbsc/mgcp.h
index 335c83d..1d74078 100644
--- a/openbsc/include/openbsc/mgcp.h
+++ b/openbsc/include/openbsc/mgcp.h
@@ -25,6 +25,7 @@
#include <osmocom/core/msgb.h>
#include <osmocom/core/write_queue.h>
+#include <osmocom/core/timer.h>
#include "debug.h"
@@ -103,6 +104,8 @@ struct mgcp_port_range {
int last_port;
};
+#define MGCP_KEEPALIVE_ONCE (-1)
+
struct mgcp_trunk_config {
struct llist_head entry;
@@ -118,6 +121,7 @@ struct mgcp_trunk_config {
int audio_loop;
int omit_rtcp;
+ int keepalive_interval;
/* RTP patching */
int force_constant_ssrc; /* 0: don't, 1: once */
@@ -126,6 +130,9 @@ struct mgcp_trunk_config {
/* spec handling */
int force_realloc;
+ /* timer */
+ struct osmo_timer_list keepalive_timer;
+
unsigned int number_endpoints;
struct mgcp_endpoint *endpoints;
};
@@ -187,6 +194,8 @@ int mgcp_reset_transcoder(struct mgcp_config *cfg);
void mgcp_format_stats(struct mgcp_endpoint *endp, char *stats, size_t size);
int mgcp_parse_stats(struct msgb *msg, uint32_t *ps, uint32_t *os, uint32_t *pr, uint32_t
*_or, int *loss, uint32_t *jitter);
+void mgcp_trunk_set_keepalive(struct mgcp_trunk_config *tcfg, int interval);
+
/*
* format helper functions
*/
diff --git a/openbsc/src/libmgcp/mgcp_protocol.c b/openbsc/src/libmgcp/mgcp_protocol.c
index b55da37..9996ba7 100644
--- a/openbsc/src/libmgcp/mgcp_protocol.c
+++ b/openbsc/src/libmgcp/mgcp_protocol.c
@@ -877,6 +877,9 @@ mgcp_header_done:
if (p->cfg->change_cb)
p->cfg->change_cb(tcfg, ENDPOINT_NUMBER(endp), MGCP_ENDP_CRCX);
+ if (endp->bts_end.output_enabled && tcfg->keepalive_interval != 0)
+ mgcp_send_dummy(endp);
+
create_transcoder(endp);
return create_response_with_sdp(endp, "CRCX", p->trans);
error2:
@@ -975,6 +978,10 @@ static struct msgb *handle_modify_con(struct mgcp_parse_data *p)
ENDPOINT_NUMBER(endp), inet_ntoa(endp->net_end.addr),
ntohs(endp->net_end.rtp_port));
if (p->cfg->change_cb)
p->cfg->change_cb(endp->tcfg, ENDPOINT_NUMBER(endp), MGCP_ENDP_MDCX);
+
+ if (endp->bts_end.output_enabled && endp->tcfg->keepalive_interval !=
0)
+ mgcp_send_dummy(endp);
+
if (silent)
goto out_silent;
@@ -1127,6 +1134,40 @@ static struct msgb *handle_noti_req(struct mgcp_parse_data *p)
create_err_response(p->endp, res, "RQNT", p->trans);
}
+static void mgcp_keepalive_timer_cb(void *_tcfg)
+{
+ struct mgcp_trunk_config *tcfg = _tcfg;
+ int i;
+ LOGP(DMGCP, LOGL_DEBUG, "Triggered trunk %d keepalive timer.\n",
+ tcfg->trunk_nr);
+
+ if (tcfg->keepalive_interval <= 0)
+ return;
+
+ for (i = 1; i < tcfg->number_endpoints; ++i) {
+ struct mgcp_endpoint *endp = &tcfg->endpoints[i];
+ if (endp->conn_mode == MGCP_CONN_RECV_ONLY)
+ mgcp_send_dummy(endp);
+ }
+
+ LOGP(DMGCP, LOGL_DEBUG, "Rescheduling trunk %d keepalive timer.\n",
+ tcfg->trunk_nr);
+ osmo_timer_schedule(&tcfg->keepalive_timer, tcfg->keepalive_interval, 0);
+}
+
+void mgcp_trunk_set_keepalive(struct mgcp_trunk_config *tcfg, int interval)
+{
+ tcfg->keepalive_interval = interval;
+ tcfg->keepalive_timer.data = tcfg;
+ tcfg->keepalive_timer.cb = mgcp_keepalive_timer_cb;
+
+ if (interval <= 0)
+ osmo_timer_del(&tcfg->keepalive_timer);
+ else
+ osmo_timer_schedule(&tcfg->keepalive_timer,
+ tcfg->keepalive_interval, 0);
+}
+
struct mgcp_config *mgcp_config_alloc(void)
{
struct mgcp_config *cfg;
@@ -1153,6 +1194,7 @@ struct mgcp_config *mgcp_config_alloc(void)
cfg->trunk.audio_payload = 126;
cfg->trunk.audio_send_ptime = 1;
cfg->trunk.omit_rtcp = 0;
+ mgcp_trunk_set_keepalive(&cfg->trunk, MGCP_KEEPALIVE_ONCE);
INIT_LLIST_HEAD(&cfg->trunks);
@@ -1177,6 +1219,7 @@ struct mgcp_trunk_config *mgcp_trunk_alloc(struct mgcp_config *cfg,
int nr)
trunk->audio_send_ptime = 1;
trunk->number_endpoints = 33;
trunk->omit_rtcp = 0;
+ mgcp_trunk_set_keepalive(trunk, MGCP_KEEPALIVE_ONCE);
llist_add_tail(&trunk->entry, &cfg->trunks);
return trunk;
}
diff --git a/openbsc/src/libmgcp/mgcp_vty.c b/openbsc/src/libmgcp/mgcp_vty.c
index 3f1ebeb..408a059 100644
--- a/openbsc/src/libmgcp/mgcp_vty.c
+++ b/openbsc/src/libmgcp/mgcp_vty.c
@@ -32,6 +32,7 @@
#define RTCP_OMIT_STR "Drop RTCP packets in both directions\n"
#define RTP_PATCH_STR "Modify RTP packet header in both directions\n"
+#define RTP_KEEPALIVE_STR "Send dummy UDP packet to net RTP destination\n"
static struct mgcp_config *g_cfg = NULL;
@@ -85,6 +86,14 @@ static int config_write_mgcp(struct vty *vty)
g_cfg->net_ports.range_start, g_cfg->net_ports.range_end, VTY_NEWLINE);
vty_out(vty, " rtp ip-dscp %d%s", g_cfg->endp_dscp, VTY_NEWLINE);
+ if (g_cfg->trunk.keepalive_interval == MGCP_KEEPALIVE_ONCE)
+ vty_out(vty, " rtp keep-alive once%s", VTY_NEWLINE);
+ else if (g_cfg->trunk.keepalive_interval)
+ vty_out(vty, " rtp keep-alive %d%s",
+ g_cfg->trunk.keepalive_interval, VTY_NEWLINE);
+ else
+ vty_out(vty, " no rtp keep-alive%s", VTY_NEWLINE);
+
if (g_cfg->trunk.omit_rtcp)
vty_out(vty, " rtcp-omit%s", VTY_NEWLINE);
else
@@ -511,6 +520,39 @@ DEFUN(cfg_mgcp_no_patch_rtp,
return CMD_SUCCESS;
}
+DEFUN(cfg_mgcp_rtp_keepalive,
+ cfg_mgcp_rtp_keepalive_cmd,
+ "rtp keep-alive <1-120>",
+ RTP_STR RTP_KEEPALIVE_STR
+ "Keep alive interval in secs\n"
+ )
+{
+ mgcp_trunk_set_keepalive(&g_cfg->trunk, atoi(argv[0]));
+ return CMD_SUCCESS;
+}
+
+DEFUN(cfg_mgcp_rtp_keepalive_once,
+ cfg_mgcp_rtp_keepalive_once_cmd,
+ "rtp keep-alive once",
+ RTP_STR RTP_KEEPALIVE_STR
+ "Send dummy packet only once after CRCX/MDCX\n"
+ )
+{
+ mgcp_trunk_set_keepalive(&g_cfg->trunk, MGCP_KEEPALIVE_ONCE);
+ return CMD_SUCCESS;
+}
+
+DEFUN(cfg_mgcp_no_rtp_keepalive,
+ cfg_mgcp_no_rtp_keepalive_cmd,
+ "no rtp keep-alive",
+ NO_STR RTP_STR RTP_KEEPALIVE_STR
+ )
+{
+ mgcp_trunk_set_keepalive(&g_cfg->trunk, 0);
+ return CMD_SUCCESS;
+}
+
+
#define CALL_AGENT_STR "Callagent information\n"
DEFUN(cfg_mgcp_agent_addr,
@@ -598,6 +640,15 @@ static int config_write_trunk(struct vty *vty)
trunk->audio_name, VTY_NEWLINE);
vty_out(vty, " %ssdp audio-payload send-ptime%s",
trunk->audio_send_ptime ? "" : "no ", VTY_NEWLINE);
+
+ if (trunk->keepalive_interval == MGCP_KEEPALIVE_ONCE)
+ vty_out(vty, " rtp keep-alive once%s", VTY_NEWLINE);
+ else if (trunk->keepalive_interval)
+ vty_out(vty, " rtp keep-alive %d%s",
+ trunk->keepalive_interval, VTY_NEWLINE);
+ else
+ vty_out(vty, " no rtp keep-alive%s", VTY_NEWLINE);
+
vty_out(vty, " loop %d%s",
trunk->audio_loop, VTY_NEWLINE);
if (trunk->omit_rtcp)
@@ -780,6 +831,40 @@ DEFUN(cfg_trunk_no_patch_rtp,
return CMD_SUCCESS;
}
+DEFUN(cfg_trunk_rtp_keepalive,
+ cfg_trunk_rtp_keepalive_cmd,
+ "rtp keep-alive <1-120>",
+ RTP_STR RTP_KEEPALIVE_STR
+ "Keep-alive interval in secs\n"
+ )
+{
+ struct mgcp_trunk_config *trunk = vty->index;
+ mgcp_trunk_set_keepalive(trunk, atoi(argv[0]));
+ return CMD_SUCCESS;
+}
+
+DEFUN(cfg_trunk_rtp_keepalive_once,
+ cfg_trunk_rtp_keepalive_once_cmd,
+ "rtp keep-alive once",
+ RTP_STR RTP_KEEPALIVE_STR
+ "Send dummy packet only once after CRCX/MDCX\n"
+ )
+{
+ struct mgcp_trunk_config *trunk = vty->index;
+ mgcp_trunk_set_keepalive(trunk, MGCP_KEEPALIVE_ONCE);
+ return CMD_SUCCESS;
+}
+
+DEFUN(cfg_trunk_no_rtp_keepalive,
+ cfg_trunk_no_rtp_keepalive_cmd,
+ "no rtp keep-alive",
+ NO_STR RTP_STR RTP_KEEPALIVE_STR
+ )
+{
+ struct mgcp_trunk_config *trunk = vty->index;
+ mgcp_trunk_set_keepalive(trunk, 0);
+ return CMD_SUCCESS;
+}
DEFUN(loop_endp,
loop_endp_cmd,
@@ -999,6 +1084,9 @@ int mgcp_vty_init(void)
install_element(MGCP_NODE, &cfg_mgcp_rtp_transcoder_base_cmd);
install_element(MGCP_NODE, &cfg_mgcp_rtp_ip_dscp_cmd);
install_element(MGCP_NODE, &cfg_mgcp_rtp_ip_tos_cmd);
+ install_element(MGCP_NODE, &cfg_mgcp_rtp_keepalive_cmd);
+ install_element(MGCP_NODE, &cfg_mgcp_rtp_keepalive_once_cmd);
+ install_element(MGCP_NODE, &cfg_mgcp_no_rtp_keepalive_cmd);
install_element(MGCP_NODE, &cfg_mgcp_agent_addr_cmd);
install_element(MGCP_NODE, &cfg_mgcp_agent_addr_cmd_old);
install_element(MGCP_NODE, &cfg_mgcp_transcoder_cmd);
@@ -1024,6 +1112,9 @@ int mgcp_vty_init(void)
install_element(MGCP_NODE, &cfg_mgcp_trunk_cmd);
install_node(&trunk_node, config_write_trunk);
vty_install_default(TRUNK_NODE);
+ install_element(TRUNK_NODE, &cfg_trunk_rtp_keepalive_cmd);
+ install_element(TRUNK_NODE, &cfg_trunk_rtp_keepalive_once_cmd);
+ install_element(TRUNK_NODE, &cfg_trunk_no_rtp_keepalive_cmd);
install_element(TRUNK_NODE, &cfg_trunk_payload_number_cmd);
install_element(TRUNK_NODE, &cfg_trunk_payload_name_cmd);
install_element(TRUNK_NODE, &cfg_trunk_payload_number_cmd_old);
diff --git a/openbsc/src/osmo-bsc_mgcp/mgcp_main.c
b/openbsc/src/osmo-bsc_mgcp/mgcp_main.c
index 596ea8a..14ec221 100644
--- a/openbsc/src/osmo-bsc_mgcp/mgcp_main.c
+++ b/openbsc/src/osmo-bsc_mgcp/mgcp_main.c
@@ -137,15 +137,6 @@ static int mgcp_rsip_cb(struct mgcp_trunk_config *tcfg)
return 0;
}
-static int mgcp_change_cb(struct mgcp_trunk_config *cfg, int endpoint, int state)
-{
- if (state != MGCP_ENDP_MDCX)
- return 0;
-
- mgcp_send_dummy(&cfg->endpoints[endpoint]);
- return 0;
-}
-
static int read_call_agent(struct osmo_fd *fd, unsigned int what)
{
struct sockaddr_in addr;
@@ -233,7 +224,6 @@ int main(int argc, char **argv)
/* set some callbacks */
cfg->reset_cb = mgcp_rsip_cb;
- cfg->change_cb = mgcp_change_cb;
/* we need to bind a socket */
if (rc == 0) {
diff --git a/openbsc/tests/mgcp/mgcp_test.ok b/openbsc/tests/mgcp/mgcp_test.ok
index 6db7226..7e8aa5c 100644
--- a/openbsc/tests/mgcp/mgcp_test.ok
+++ b/openbsc/tests/mgcp/mgcp_test.ok
@@ -16,6 +16,7 @@ Testing AUEP2
Testing MDCX1
Testing MDCX2
Testing CRCX
+Dummy packets: 1
Detected packet duration: 40
Requested packetetization period: 20-20
Connection mode: 1, BTS output enabled, NET output disabled
@@ -24,18 +25,22 @@ Packet duration not set
Requested packetization period not set
Connection mode not set
Testing MDCX4
+Dummy packets: 1
Detected packet duration: 40
Requested packetetization period: 20-20
Connection mode: 3, BTS output enabled, NET output enabled
Testing MDCX4_PT1
+Dummy packets: 1
Detected packet duration: 40
Requested packetetization period: 20-40
Connection mode: 3, BTS output enabled, NET output enabled
Testing MDCX4_PT2
+Dummy packets: 1
Detected packet duration: 40
Requested packetetization period: 20-20
Connection mode: 3, BTS output enabled, NET output enabled
Testing MDCX4_PT3
+Dummy packets: 1
Detected packet duration: 40
Requested packetization period not set
Connection mode: 3, BTS output enabled, NET output enabled
@@ -48,6 +53,7 @@ Detected packet duration: 20
Requested packetization period not set
Connection mode: 0, BTS output enabled, NET output enabled
Testing CRCX_ZYN
+Dummy packets: 1
Packet duration not set
Requested packetization period not set
Connection mode: 1, BTS output enabled, NET output disabled
--
1.7.9.5