ggsn: Add ability to specify local IP addresses for GTP-C and GTP-U
In case the GGSN is behind some kind of DNAT, the public GTP-C and
GTP-U IP addresses as exposed inside the GTP payload information
elements are different from the (internal, behind-nat) IP address
to which it listens/binds.
Change-Id: I548c9011c9abd66d46f963b1def61575f3dabb89
diff --git a/ggsn/ggsn.c b/ggsn/ggsn.c
index 0b877cf..46850a6 100644
--- a/ggsn/ggsn.c
+++ b/ggsn/ggsn.c
@@ -693,6 +693,14 @@
}
ggsn->gsn->priv = ggsn;
+ /* patch in different addresses to use (in case we're behind NAT, the listen
+ * address is different from what we advertise externally) */
+ if (ggsn->cfg.gtpc_addr.v4.s_addr)
+ ggsn->gsn->gsnc = ggsn->cfg.gtpc_addr.v4;
+
+ if (ggsn->cfg.gtpu_addr.v4.s_addr)
+ ggsn->gsn->gsnu = ggsn->cfg.gtpu_addr.v4;
+
/* Register File Descriptors */
osmo_fd_setup(&ggsn->gtp_fd0, ggsn->gsn->fd0, BSC_FD_READ, ggsn_gtp_fd_cb, ggsn, 0);
rc = osmo_fd_register(&ggsn->gtp_fd0);
diff --git a/ggsn/ggsn.h b/ggsn/ggsn.h
index bab6cf7..2dd963c 100644
--- a/ggsn/ggsn.h
+++ b/ggsn/ggsn.h
@@ -99,6 +99,10 @@
struct apn_ctx *default_apn;
/* ADdress to which we listen for GTP */
struct in46_addr listen_addr;
+ /* Local GTP-C address advertised in GTP */
+ struct in46_addr gtpc_addr;
+ /* Local GTP-U address advertised in GTP */
+ struct in46_addr gtpu_addr;
/* directory for state file */
char *state_dir;
/* administratively shut-down (true) or not (false) */
diff --git a/ggsn/ggsn_vty.c b/ggsn/ggsn_vty.c
index 4a3e753..d7bd9a7 100644
--- a/ggsn/ggsn_vty.c
+++ b/ggsn/ggsn_vty.c
@@ -165,8 +165,8 @@
return CMD_SUCCESS;
}
-DEFUN(cfg_ggsn_local_ip, cfg_ggsn_local_ip_cmd,
- "gtp local-ip A.B.C.D",
+DEFUN(cfg_ggsn_bind_ip, cfg_ggsn_bind_ip_cmd,
+ "gtp bind-ip A.B.C.D",
"GTP Parameters\n"
"Set the IP address for the local GTP bind\n"
"IPv4 Address\n")
@@ -179,6 +179,34 @@
return CMD_SUCCESS;
}
+DEFUN(cfg_ggsn_gtpc_ip, cfg_ggsn_gtpc_ip_cmd,
+ "gtp control-ip A.B.C.D",
+ "GTP Parameters\n"
+ "Set the IP address states as local IP in GTP-C messages\n"
+ "IPv4 Address\n")
+{
+ struct ggsn_ctx *ggsn = (struct ggsn_ctx *) vty->index;
+ size_t t;
+
+ ippool_aton(&ggsn->cfg.gtpc_addr, &t, argv[0], 0);
+
+ return CMD_SUCCESS;
+}
+
+DEFUN(cfg_ggsn_gtpu_ip, cfg_ggsn_gtpu_ip_cmd,
+ "gtp user-ip A.B.C.D",
+ "GTP Parameters\n"
+ "Set the IP address states as local IP in GTP-U messages\n"
+ "IPv4 Address\n")
+{
+ struct ggsn_ctx *ggsn = (struct ggsn_ctx *) vty->index;
+ size_t t;
+
+ ippool_aton(&ggsn->cfg.gtpu_addr, &t, argv[0], 0);
+
+ return CMD_SUCCESS;
+}
+
DEFUN(cfg_ggsn_state_dir, cfg_ggsn_state_dir_cmd,
"gtp state-dir PATH",
"GTP Parameters\n"
@@ -633,7 +661,11 @@
if (ggsn->cfg.description)
vty_out(vty, " description %s%s", ggsn->cfg.description, VTY_NEWLINE);
vty_out(vty, " gtp state-dir %s%s", ggsn->cfg.state_dir, VTY_NEWLINE);
- vty_out(vty, " gtp local-ip %s%s", in46a_ntoa(&ggsn->cfg.listen_addr), VTY_NEWLINE);
+ vty_out(vty, " gtp bind-ip %s%s", in46a_ntoa(&ggsn->cfg.listen_addr), VTY_NEWLINE);
+ if (ggsn->cfg.gtpc_addr.v4.s_addr)
+ vty_out(vty, " gtp control-ip %s%s", in46a_ntoa(&ggsn->cfg.gtpc_addr), VTY_NEWLINE);
+ if (ggsn->cfg.gtpu_addr.v4.s_addr)
+ vty_out(vty, " gtp user-ip %s%s", in46a_ntoa(&ggsn->cfg.gtpu_addr), VTY_NEWLINE);
llist_for_each_entry(apn, &ggsn->apn_list, list)
config_write_apn(vty, apn);
if (ggsn->cfg.default_apn)
@@ -806,7 +838,9 @@
install_element(GGSN_NODE, &cfg_no_description_cmd);
install_element(GGSN_NODE, &cfg_ggsn_shutdown_cmd);
install_element(GGSN_NODE, &cfg_ggsn_no_shutdown_cmd);
- install_element(GGSN_NODE, &cfg_ggsn_local_ip_cmd);
+ install_element(GGSN_NODE, &cfg_ggsn_bind_ip_cmd);
+ install_element(GGSN_NODE, &cfg_ggsn_gtpc_ip_cmd);
+ install_element(GGSN_NODE, &cfg_ggsn_gtpu_ip_cmd);
install_element(GGSN_NODE, &cfg_ggsn_state_dir_cmd);
install_element(GGSN_NODE, &cfg_ggsn_apn_cmd);
install_element(GGSN_NODE, &cfg_ggsn_no_apn_cmd);