gtphub: implement sgsn_use_sender for NAT.
If an SGSN is behind NAT, we cannot rely on the default ports. Specifically,
if a GGSN sends a message, the forwarding to the SGSN should go to whichever
port the SGSN last sent from (whether sequence nr is known or not).
Add sgsn_use_sender config and VTY command, and store the sender instead
of the GSN Address IE and default port if set.
Sponsored-by: On-Waves ehi
diff --git a/openbsc/src/gprs/gtphub_vty.c b/openbsc/src/gprs/gtphub_vty.c
index 204d1de..324d155 100644
--- a/openbsc/src/gprs/gtphub_vty.c
+++ b/openbsc/src/gprs/gtphub_vty.c
@@ -87,6 +87,10 @@
&g_cfg->to_gsns[GTPH_SIDE_GGSN][GTPH_PLANE_CTRL].bind,
&g_cfg->to_gsns[GTPH_SIDE_GGSN][GTPH_PLANE_USER].bind);
+ if (g_cfg->sgsn_use_sender) {
+ vty_out(vty, "sgsn-use-sender%s", VTY_NEWLINE);
+ }
+
if (g_cfg->proxy[GTPH_SIDE_SGSN][GTPH_PLANE_CTRL].addr_str) {
write_addrs(vty, "sgsn-proxy",
&g_cfg->proxy[GTPH_SIDE_SGSN][GTPH_PLANE_CTRL],
@@ -237,6 +241,28 @@
}
+#define SGSN_USE_SENDER_STR \
+ "Ignore SGSN's Address IEs, use sender address and port (useful over NAT)\n"
+
+DEFUN(cfg_gtphub_sgsn_use_sender,
+ cfg_gtphub_sgsn_use_sender_cmd,
+ "sgsn-use-sender",
+ SGSN_USE_SENDER_STR)
+{
+ g_cfg->sgsn_use_sender = 1;
+ return CMD_SUCCESS;
+}
+
+DEFUN(cfg_gtphub_no_sgsn_use_sender,
+ cfg_gtphub_no_sgsn_use_sender_cmd,
+ "no sgsn-use-sender",
+ NO_STR SGSN_USE_SENDER_STR)
+{
+ g_cfg->sgsn_use_sender = 0;
+ return CMD_SUCCESS;
+}
+
+
/* Copied from sgsn_vty.h */
DEFUN(cfg_grx_ggsn, cfg_grx_ggsn_cmd,
"grx-dns-add A.B.C.D",
@@ -425,6 +451,8 @@
install_element(GTPHUB_NODE, &cfg_gtphub_ggsn_proxy_cmd);
install_element(GTPHUB_NODE, &cfg_gtphub_sgsn_proxy_short_cmd);
install_element(GTPHUB_NODE, &cfg_gtphub_sgsn_proxy_cmd);
+ install_element(GTPHUB_NODE, &cfg_gtphub_sgsn_use_sender_cmd);
+ install_element(GTPHUB_NODE, &cfg_gtphub_no_sgsn_use_sender_cmd);
install_element(GTPHUB_NODE, &cfg_grx_ggsn_cmd);
return 0;