[nat] Add VTY support to the BSC nat application

* Create struct bsc_nat and move the various lists into this structure
* Create the VTY code
* Call the VTY init and parsing code
* Create functions to create the types..
* Add some stuff into the bsc_connection to be used for the NAT with
  proper config files. E.g. to close the connection if the BSC does not
  respond to a given command.

openbsc/include/openbsc/bsc_nat.h

@@ -27,6 +27,7 @@
 
 #include "select.h"
 #include "msgb.h"
+#include "timer.h"
 
 #define DIR_BSC 1
 #define DIR_MSC 2
@@ -75,6 +76,12 @@ struct bsc_connection {
 
 	/* the fd we use to communicate */
 	struct bsc_fd bsc_fd;
+
+	/* the LAC assigned to this connection */
+	unsigned int lac;
+
+	/* a timeout node */
+	struct timer_list id_timeout;
 };
 
 /*
@@ -91,6 +98,38 @@ struct sccp_connections {
 	struct sccp_source_reference patched_ref;
 };
 
+/**
+ * One BSC entry in the config
+ */
+struct bsc_config {
+	struct llist_head entry;
+
+	char *token;
+	unsigned int lac;
+	int nr;
+
+	struct bsc_nat *nat;
+};
+
+/**
+ * the structure of the "nat" network
+ */
+struct bsc_nat {
+	/* active SCCP connections that need patching */
+	struct llist_head sccp_connections;
+
+	/* active BSC connections that need patching */
+	struct llist_head bsc_connections;
+
+	/* known BSC's */
+	struct llist_head bsc_configs;
+	int num_bsc;
+};
+
+/* create and init the structures */
+struct bsc_config *bsc_config_alloc(struct bsc_nat *nat, const char *token, unsigned int lac);
+struct bsc_config *bsc_config_num(struct bsc_nat *nat, int num);
+
 
 /**
  * parse the given message into the above structure
@@ -101,5 +140,6 @@ struct bsc_nat_parsed *bsc_nat_parse(struct msgb *msg);
  * filter based on IP Access header in both directions
  */
 int bsc_nat_filter_ipa(int direction, struct msgb *msg, struct bsc_nat_parsed *parsed);
+int bsc_nat_vty_init(struct bsc_nat *nat);
 
 #endif

openbsc/src/nat/bsc_nat.c

@@ -43,19 +43,69 @@
 #include <openbsc/ipaccess.h>
 #include <openbsc/abis_nm.h>
 #include <openbsc/talloc.h>
-#include <openbsc/linuxlist.h>
+#include <openbsc/telnet_interface.h>
+
+#include <vty/vty.h>
 
 #include <sccp/sccp.h>
 
-static const char *config_file = "openbsc.cfg";
+static const char *config_file = "bsc-nat.cfg";
 static char *msc_address = "127.0.0.1";
 static struct in_addr local_addr;
 static struct bsc_fd msc_connection;
 static struct bsc_fd bsc_connection;
 
 
-static LLIST_HEAD(bsc_connections);
+static struct bsc_nat *nat;
-static LLIST_HEAD(sccp_connections);
+
+static struct bsc_nat *bsc_nat_alloc(void)
+{
+	struct bsc_nat *nat = talloc_zero(tall_bsc_ctx, struct bsc_nat);
+	if (!nat)
+		return NULL;
+
+	INIT_LLIST_HEAD(&nat->sccp_connections);
+	INIT_LLIST_HEAD(&nat->bsc_connections);
+	INIT_LLIST_HEAD(&nat->bsc_configs);
+	return nat;
+}
+
+static struct bsc_connection *bsc_connection_alloc(void)
+{
+	struct bsc_connection *con = talloc_zero(nat, struct bsc_connection);
+	if (!con)
+		return NULL;
+
+	return con;
+}
+
+struct bsc_config *bsc_config_alloc(struct bsc_nat *nat, const char *token, unsigned int lac)
+{
+	struct bsc_config *conf = talloc_zero(nat, struct bsc_config);
+	if (!conf)
+		return NULL;
+
+	conf->token = talloc_strdup(conf, token);
+	conf->lac = lac;
+	conf->nr = nat->num_bsc;
+	conf->nat = nat;
+
+	llist_add(&conf->entry, &nat->bsc_configs);
+	++nat->num_bsc;
+
+	return conf;
+}
+
+struct bsc_config *bsc_config_num(struct bsc_nat *nat, int num)
+{
+	struct bsc_config *conf;
+
+	llist_for_each_entry(conf, &nat->bsc_configs, entry)
+		if (conf->nr == num)
+			return conf;
+
+	return NULL;
+}
 
 /*
  * below are stubs we need to link
@@ -95,7 +145,7 @@ static int sccp_ref_is_free(struct sccp_source_reference *ref)
 {
 	struct sccp_connections *conn;
 
-	llist_for_each_entry(conn, &sccp_connections, list_entry) {
+	llist_for_each_entry(conn, &nat->sccp_connections, list_entry) {
 		if (memcmp(ref, &conn->patched_ref, sizeof(*ref)) == 0)
 			return -1;
 	}
@@ -137,7 +187,7 @@ static int create_sccp_src_ref(struct bsc_connection *bsc, struct msgb *msg, str
 {
 	struct sccp_connections *conn;
 
-	conn = talloc_zero(tall_bsc_ctx, struct sccp_connections);
+	conn = talloc_zero(nat, struct sccp_connections);
 	if (!conn) {
 		LOGP(DNAT, LOGL_ERROR, "Memory allocation failure.\n");
 		return -1;
@@ -157,7 +207,7 @@ static void remove_sccp_src_ref(struct bsc_connection *bsc, struct msgb *msg, st
 {
 	struct sccp_connections *conn;
 
-	llist_for_each_entry(conn, &sccp_connections, list_entry) {
+	llist_for_each_entry(conn, &nat->sccp_connections, list_entry) {
 		if (memcmp(parsed->src_local_ref,
 			   &conn->real_ref, sizeof(conn->real_ref)) == 0) {
 			if (bsc != conn->bsc) {
@@ -178,7 +228,7 @@ static void remove_sccp_src_ref(struct bsc_connection *bsc, struct msgb *msg, st
 static struct bsc_connection *patch_sccp_src_ref_to_bsc(struct msgb *msg, struct bsc_nat_parsed *parsed)
 {
 	struct sccp_connections *conn;
-	llist_for_each_entry(conn, &sccp_connections, list_entry) {
+	llist_for_each_entry(conn, &nat->sccp_connections, list_entry) {
 		if (memcmp(parsed->dest_local_ref,
 			   &conn->real_ref, sizeof(*parsed->dest_local_ref)) == 0) {
 			memcpy(parsed->dest_local_ref,
@@ -193,7 +243,7 @@ static struct bsc_connection *patch_sccp_src_ref_to_bsc(struct msgb *msg, struct
 static struct bsc_connection *patch_sccp_src_ref_to_msc(struct msgb *msg, struct bsc_nat_parsed *parsed)
 {
 	struct sccp_connections *conn;
-	llist_for_each_entry(conn, &sccp_connections, list_entry) {
+	llist_for_each_entry(conn, &nat->sccp_connections, list_entry) {
 		if (memcmp(parsed->src_local_ref,
 			   &conn->real_ref, sizeof(*parsed->src_local_ref)) == 0) {
 			memcpy(parsed->src_local_ref,
@@ -262,7 +312,7 @@ static int forward_sccp_to_bts(struct msgb *msg)
 
 send_to_all:
 	/* currently send this to every BSC connected */
-	llist_for_each_entry(bsc, &bsc_connections, list_entry) {
+	llist_for_each_entry(bsc, &nat->bsc_connections, list_entry) {
 		rc = write(bsc->bsc_fd.fd, msg->data, msg->len);
 
 		/* try the next one */
@@ -324,7 +374,7 @@ static void remove_bsc_connection(struct bsc_connection *connection)
 	llist_del(&connection->list_entry);
 
 	/* remove all SCCP connections */
-	llist_for_each_entry_safe(sccp_patch, tmp, &sccp_connections, list_entry) {
+	llist_for_each_entry_safe(sccp_patch, tmp, &nat->sccp_connections, list_entry) {
 		if (sccp_patch->bsc != connection)
 			continue;
 
@@ -451,7 +501,7 @@ static int ipaccess_listen_bsc_cb(struct bsc_fd *bfd, unsigned int what)
 	/*
 	 *
 	 */
-	bsc = talloc_zero(tall_bsc_ctx, struct bsc_connection);
+	bsc = bsc_connection_alloc();
 	if (!bsc) {
 		LOGP(DNAT, LOGL_ERROR, "Failed to allocate BSC struct.\n");
 		close(ret);
@@ -470,7 +520,7 @@ static int ipaccess_listen_bsc_cb(struct bsc_fd *bfd, unsigned int what)
 	}
 
 	LOGP(DNAT, LOGL_INFO, "Registered new BSC\n");
-	llist_add(&bsc->list_entry, &bsc_connections);
+	llist_add(&bsc->list_entry, &nat->bsc_connections);
 	ipaccess_send_id_ack(ret);
 	return 0;
 }
@@ -600,6 +650,20 @@ int main(int argc, char** argv)
 	local_addr.s_addr = INADDR_ANY;
 	handle_options(argc, argv);
 
+	nat = bsc_nat_alloc();
+	if (!nat) {
+		fprintf(stderr, "Failed to allocate the BSC nat.\n");
+		return -4;
+	}
+
+	/* init vty and parse */
+	bsc_nat_vty_init(nat);
+	telnet_init(NULL, 4244);
+	if (vty_read_config_file(config_file) < 0) {
+		fprintf(stderr, "Failed to parse the config file: '%s'\n", config_file);
+		return -3;
+	}
+
 	/* seed the PRNG */
 	srand(time(NULL));
 

openbsc/src/nat/bsc_nat_vty.c

@@ -0,0 +1,207 @@
+/* OpenBSC NAT interface to quagga VTY */
+/* (C) 2010 by Holger Hans Peter Freyther
+ * (C) 2010 by On-Waves
+ * All Rights Reserved
+ *
+ * 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, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ */
+
+#include <vty/command.h>
+#include <vty/buffer.h>
+#include <vty/vty.h>
+
+#include <openbsc/bsc_nat.h>
+#include <openbsc/gsm_04_08.h>
+#include <openbsc/talloc.h>
+
+#include <sccp/sccp.h>
+
+#include <stdlib.h>
+
+static struct bsc_nat *_nat;
+
+static struct cmd_node nat_node = {
+	NAT_NODE,
+	"%s(nat)#",
+	1,
+};
+
+static struct cmd_node bsc_node = {
+	BSC_NODE,
+	"%s(bsc)#",
+	1,
+};
+
+static int config_write_nat(struct vty *vty)
+{
+	vty_out(vty, "nat%s", VTY_NEWLINE);
+	return CMD_SUCCESS;
+}
+
+static void config_write_bsc_single(struct vty *vty, struct bsc_config *bsc)
+{
+	vty_out(vty, " bsc %u%s", bsc->nr, VTY_NEWLINE);
+	vty_out(vty, "  token %s%s", bsc->token, VTY_NEWLINE);
+	vty_out(vty, "  lac %u%s", bsc->lac, VTY_NEWLINE);
+}
+
+static int config_write_bsc(struct vty *vty)
+{
+	struct bsc_config *bsc;
+
+	llist_for_each_entry(bsc, &_nat->bsc_configs, entry)
+		config_write_bsc_single(vty, bsc);
+	return CMD_SUCCESS;
+}
+
+
+DEFUN(show_sccp, show_sccp_cmd, "show connections sccp",
+      SHOW_STR "Display information about current SCCP connections")
+{
+	struct sccp_connections *con;
+	llist_for_each_entry(con, &_nat->sccp_connections, list_entry) {
+		vty_out(vty, "SCCP for BSC: %d BSC ref: %u Local ref: %u%s",
+			con->bsc->lac,
+			sccp_src_ref_to_int(&con->real_ref),
+			sccp_src_ref_to_int(&con->patched_ref), VTY_NEWLINE);
+	}
+
+	return CMD_SUCCESS;
+}
+
+DEFUN(show_bsc, show_bsc_cmd, "show connections bsc",
+      SHOW_STR "Display information about current BSCs")
+{
+	struct bsc_connection *con;
+	llist_for_each_entry(con, &_nat->bsc_connections, list_entry) {
+		vty_out(vty, "BSC lac: %d auth: %d fd: %d%s",
+			con->lac, con->authenticated, con->bsc_fd.fd, VTY_NEWLINE);
+	}
+
+	return CMD_SUCCESS;
+}
+
+DEFUN(show_bsc_cfg, show_bsc_cfg_cmd, "show bsc config",
+      SHOW_STR "Display information about known BSC configs")
+{
+	struct bsc_config *conf;
+	llist_for_each_entry(conf, &_nat->bsc_configs, entry) {
+		vty_out(vty, "BSC token: '%s' lac: %u nr: %u%s",
+			conf->token, conf->lac, conf->nr, VTY_NEWLINE);
+	}
+
+	return CMD_SUCCESS;
+}
+
+
+DEFUN(cfg_nat, cfg_nat_cmd, "nat", "Configute the NAT")
+{
+	vty->index = _nat;
+	vty->node = NAT_NODE;
+
+	return CMD_SUCCESS;
+}
+
+/* per BSC configuration */
+DEFUN(cfg_bsc, cfg_bsc_cmd, "bsc BSC_NR", "Select a BSC to configure\n")
+{
+	int bsc_nr = atoi(argv[0]);
+	struct bsc_config *bsc;
+
+	if (bsc_nr > _nat->num_bsc) {
+		vty_out(vty, "%% The next unused BSC number is %u%s",
+			_nat->num_bsc, VTY_NEWLINE);
+		return CMD_WARNING;
+	} else if (bsc_nr == _nat->num_bsc) {
+		/* allocate a new one */
+		bsc = bsc_config_alloc(_nat, "unknown", 0);
+	} else
+		bsc = bsc_config_num(_nat, bsc_nr);
+
+	if (!bsc)
+		return CMD_WARNING;
+
+	vty->index = bsc;
+	vty->node = BSC_NODE;
+
+	return CMD_SUCCESS;
+}
+
+DEFUN(cfg_bsc_token, cfg_bsc_token_cmd, "token TOKEN", "Set the token")
+{
+	struct bsc_config *conf = vty->index;
+
+	if (conf->token)
+	    talloc_free(conf->token);
+	conf->token = talloc_strdup(conf, argv[0]);
+	return CMD_SUCCESS;
+}
+
+DEFUN(cfg_bsc_lac, cfg_bsc_lac_cmd, "location_area_code <0-65535>",
+      "Set the Location Area Code (LAC) of this BSC\n")
+{
+	struct bsc_config *conf = vty->index;
+
+	int lac = atoi(argv[0]);
+
+	if (lac < 0 || lac > 0xffff) {
+		vty_out(vty, "%% LAC %d is not in the valid range (0-65535)%s",
+			lac, VTY_NEWLINE);
+		return CMD_WARNING;
+	}
+
+	if (lac == GSM_LAC_RESERVED_DETACHED || lac == GSM_LAC_RESERVED_ALL_BTS) {
+		vty_out(vty, "%% LAC %d is reserved by GSM 04.08%s",
+			lac, VTY_NEWLINE);
+		return CMD_WARNING;
+	}
+
+	conf->lac = lac;
+
+	return CMD_SUCCESS;
+}
+
+int bsc_nat_vty_init(struct bsc_nat *nat)
+{
+	_nat = nat;
+
+	cmd_init(1);
+	vty_init();
+
+	/* show commands */
+	install_element(VIEW_NODE, &show_sccp_cmd);
+	install_element(VIEW_NODE, &show_bsc_cmd);
+	install_element(VIEW_NODE, &show_bsc_cfg_cmd);
+
+	/* nat group */
+	install_element(CONFIG_NODE, &cfg_nat_cmd);
+	install_node(&nat_node, config_write_nat);
+	install_default(NAT_NODE);
+
+	/* BSC subgroups */
+	install_element(NAT_NODE, &cfg_bsc_cmd);
+	install_node(&bsc_node, config_write_bsc);
+	install_default(BSC_NODE);
+	install_element(BSC_NODE, &cfg_bsc_token_cmd);
+	install_element(BSC_NODE, &cfg_bsc_lac_cmd);
+
+	return 0;
+}
+
+
+/* called by the telnet interface... we have our own init above */
+void bsc_vty_init()
+{}