213 lines
5.7 KiB
C
213 lines
5.7 KiB
C
/*
|
|
* (C) 2010 by Holger Hans Peter Freyther <zecke@selfish.org>
|
|
* (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.
|
|
*
|
|
*/
|
|
|
|
#ifndef BSC_NAT_H
|
|
#define BSC_NAT_H
|
|
|
|
#include "mgcp.h"
|
|
|
|
#include <sys/types.h>
|
|
#include <sccp/sccp_types.h>
|
|
|
|
#include <osmocore/select.h>
|
|
#include <osmocore/msgb.h>
|
|
#include <osmocore/timer.h>
|
|
#include <osmocore/write_queue.h>
|
|
|
|
#define DIR_BSC 1
|
|
#define DIR_MSC 2
|
|
|
|
#define NAT_IPAC_PROTO_MGCP 0xfc
|
|
|
|
struct bsc_nat;
|
|
|
|
/*
|
|
* For the NAT we will need to analyze and later patch
|
|
* the received message. This would require us to parse
|
|
* the IPA and SCCP header twice. Instead of doing this
|
|
* we will have one analyze structure and have the patching
|
|
* and filter operate on the same structure.
|
|
*/
|
|
struct bsc_nat_parsed {
|
|
/* ip access prototype */
|
|
int ipa_proto;
|
|
|
|
/* source local reference */
|
|
struct sccp_source_reference *src_local_ref;
|
|
|
|
/* destination local reference */
|
|
struct sccp_source_reference *dest_local_ref;
|
|
|
|
/* called ssn number */
|
|
int called_ssn;
|
|
|
|
/* calling ssn number */
|
|
int calling_ssn;
|
|
|
|
/* sccp message type */
|
|
int sccp_type;
|
|
|
|
/* bssap type, e.g. 0 for BSS Management */
|
|
int bssap;
|
|
|
|
/* the gsm0808 message type */
|
|
int gsm_type;
|
|
};
|
|
|
|
/*
|
|
* Per BSC data structure
|
|
*/
|
|
struct bsc_connection {
|
|
struct llist_head list_entry;
|
|
|
|
/* do we know anything about this BSC? */
|
|
int authenticated;
|
|
|
|
/* the fd we use to communicate */
|
|
struct write_queue write_queue;
|
|
|
|
/* the BSS associated */
|
|
struct bsc_config *cfg;
|
|
|
|
/* a timeout node */
|
|
struct timer_list id_timeout;
|
|
|
|
/* a back pointer */
|
|
struct bsc_nat *nat;
|
|
};
|
|
|
|
/*
|
|
* Per SCCP source local reference patch table. It needs to
|
|
* be updated on new SCCP connections, connection confirm and reject,
|
|
* and on the loss of the BSC connection.
|
|
*/
|
|
struct sccp_connections {
|
|
struct llist_head list_entry;
|
|
|
|
struct bsc_connection *bsc;
|
|
|
|
struct sccp_source_reference real_ref;
|
|
struct sccp_source_reference patched_ref;
|
|
struct sccp_source_reference remote_ref;
|
|
|
|
/* GSM audio handling. That is 32 * multiplex + ts */
|
|
int msc_timeslot;
|
|
int bsc_timeslot;
|
|
};
|
|
|
|
/**
|
|
* One BSC entry in the config
|
|
*/
|
|
struct bsc_config {
|
|
struct llist_head entry;
|
|
|
|
char *token;
|
|
unsigned int lac;
|
|
int nr;
|
|
|
|
struct bsc_nat *nat;
|
|
};
|
|
|
|
/**
|
|
* BSCs point of view of endpoints
|
|
*/
|
|
struct bsc_endpoint {
|
|
/* the pending transaction id */
|
|
char *transaction_id;
|
|
/* the bsc we are talking to */
|
|
struct bsc_connection *bsc;
|
|
/* pending delete */
|
|
int pending_delete;
|
|
};
|
|
|
|
/**
|
|
* 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;
|
|
|
|
/* MGCP config */
|
|
struct mgcp_config *mgcp_cfg;
|
|
struct write_queue mgcp_queue;
|
|
u_int8_t mgcp_msg[4096];
|
|
int mgcp_length;
|
|
|
|
struct bsc_endpoint *bsc_endpoints;
|
|
};
|
|
|
|
/* 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);
|
|
struct bsc_nat *bsc_nat_alloc(void);
|
|
struct bsc_connection *bsc_connection_alloc(struct bsc_nat *nat);
|
|
|
|
void sccp_connection_destroy(struct sccp_connections *);
|
|
|
|
/**
|
|
* parse the given message into the above structure
|
|
*/
|
|
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);
|
|
struct bsc_connection *bsc_nat_find_bsc(struct bsc_nat *nat, struct msgb *msg);
|
|
|
|
/**
|
|
* SCCP patching and handling
|
|
*/
|
|
int create_sccp_src_ref(struct bsc_connection *bsc, struct msgb *msg, struct bsc_nat_parsed *parsed);
|
|
int update_sccp_src_ref(struct sccp_connections *sccp, struct bsc_nat_parsed *parsed);
|
|
void remove_sccp_src_ref(struct bsc_connection *bsc, struct msgb *msg, struct bsc_nat_parsed *parsed);
|
|
struct sccp_connections *patch_sccp_src_ref_to_bsc(struct msgb *, struct bsc_nat_parsed *, struct bsc_nat *);
|
|
struct sccp_connections *patch_sccp_src_ref_to_msc(struct msgb *, struct bsc_nat_parsed *, struct bsc_nat *);
|
|
|
|
/**
|
|
* MGCP/Audio handling
|
|
*/
|
|
int bsc_write_mgcp_msg(struct bsc_connection *bsc, struct msgb *msg);
|
|
int bsc_write_mgcp(struct bsc_connection *bsc, const u_int8_t *data, unsigned int length);
|
|
int bsc_mgcp_assign(struct sccp_connections *, struct msgb *msg);
|
|
void bsc_mgcp_clear(struct sccp_connections *);
|
|
void bsc_mgcp_free_endpoint(struct bsc_nat *nat, int);
|
|
void bsc_mgcp_free_endpoints(struct bsc_nat *nat);
|
|
int bsc_mgcp_init(struct bsc_nat *nat);
|
|
|
|
struct bsc_connection *bsc_mgcp_find_con(struct bsc_nat *, int endpoint_number);
|
|
struct msgb *bsc_mgcp_rewrite(char *input, int length, const char *ip, int port);
|
|
void bsc_mgcp_forward(struct bsc_connection *bsc, struct msgb *msg);
|
|
|
|
void bsc_mgcp_clear_endpoints_for(struct bsc_connection *bsc);
|
|
int bsc_mgcp_parse_response(const char *str, int *code, char transaction[60]);
|
|
int bsc_mgcp_extract_ci(const char *resp);
|
|
|
|
#endif
|