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Diffstat (limited to 'include/openbsc/bsc_nat.h')
-rw-r--r-- | include/openbsc/bsc_nat.h | 355 |
1 files changed, 355 insertions, 0 deletions
diff --git a/include/openbsc/bsc_nat.h b/include/openbsc/bsc_nat.h new file mode 100644 index 000000000..f74cae2a8 --- /dev/null +++ b/include/openbsc/bsc_nat.h @@ -0,0 +1,355 @@ +/* + * (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 Affero General Public License as published by + * the Free Software Foundation; either version 3 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 Affero General Public License for more details. + * + * You should have received a copy of the GNU Affero General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + * + */ + +#ifndef BSC_NAT_H +#define BSC_NAT_H + +#include "mgcp.h" + +#include <sys/types.h> + +#include <osmocore/select.h> +#include <osmocore/msgb.h> +#include <osmocore/msgfile.h> +#include <osmocore/timer.h> +#include <osmocore/write_queue.h> +#include <osmocore/rate_ctr.h> +#include <osmocore/statistics.h> +#include <osmocore/protocol/gsm_04_08.h> + +#include <regex.h> + +#define DIR_BSC 1 +#define DIR_MSC 2 + +struct sccp_source_reference; +struct sccp_connections; +struct bsc_nat_parsed; +struct bsc_nat; +struct bsc_nat_ussd_con; + +enum { + NAT_CON_TYPE_NONE, + NAT_CON_TYPE_LU, + NAT_CON_TYPE_CM_SERV_REQ, + NAT_CON_TYPE_PAG_RESP, + NAT_CON_TYPE_SSA, + NAT_CON_TYPE_LOCAL_REJECT, + NAT_CON_TYPE_OTHER, +}; + +/* + * 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; + + /* pong timeout */ + struct timer_list ping_timeout; + struct timer_list pong_timeout; + + /* mgcp related code */ + char *_endpoint_status; + int number_multiplexes; + int max_endpoints; + int last_endpoint; + + /* a back pointer */ + struct bsc_nat *nat; +}; + +/** + * Stats per BSC + */ +struct bsc_config_stats { + struct rate_ctr_group *ctrg; +}; + +enum bsc_cfg_ctr { + BCFG_CTR_SCCP_CONN, + BCFG_CTR_SCCP_CALLS, + BCFG_CTR_NET_RECONN, + BCFG_CTR_DROPPED_SCCP, + BCFG_CTR_DROPPED_CALLS, + BCFG_CTR_REJECTED_CR, + BCFG_CTR_REJECTED_MSG, + BCFG_CTR_ILL_PACKET, + BCFG_CTR_CON_TYPE_LU, + BCFG_CTR_CON_CMSERV_RQ, + BCFG_CTR_CON_PAG_RESP, + BCFG_CTR_CON_SSA, + BCFG_CTR_CON_OTHER, +}; + +/** + * One BSC entry in the config + */ +struct bsc_config { + struct llist_head entry; + + char *token; + int nr; + + char *description; + + /* imsi white and blacklist */ + char *acc_lst_name; + + int forbid_paging; + + /* audio handling */ + int max_endpoints; + + /* backpointer */ + struct bsc_nat *nat; + + struct bsc_config_stats stats; + + struct llist_head lac_list; +}; + +struct bsc_lac_entry { + struct llist_head entry; + uint16_t lac; +}; + +/** + * BSCs point of view of endpoints + */ +struct bsc_endpoint { + /* the operation that is carried out */ + int transaction_state; + /* the pending transaction id */ + char *transaction_id; + /* the bsc we are talking to */ + struct bsc_connection *bsc; +}; + +/** + * Statistic for the nat. + */ +struct bsc_nat_statistics { + struct { + struct counter *conn; + struct counter *calls; + } sccp; + + struct { + struct counter *reconn; + struct counter *auth_fail; + } bsc; + + struct { + struct counter *reconn; + } msc; + + struct { + struct counter *reconn; + } ussd; +}; + +enum bsc_nat_acc_ctr { + ACC_LIST_BSC_FILTER, + ACC_LIST_NAT_FILTER, +}; + +struct bsc_nat_acc_lst { + struct llist_head list; + + /* counter */ + struct rate_ctr_group *stats; + + /* the name of the list */ + const char *name; + struct llist_head fltr_list; +}; + +struct bsc_nat_acc_lst_entry { + struct llist_head list; + + /* the filter */ + char *imsi_allow; + regex_t imsi_allow_re; + char *imsi_deny; + regex_t imsi_deny_re; +}; + +/** + * 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; + + /* access lists */ + struct llist_head access_lists; + + /* known BSC's */ + struct llist_head bsc_configs; + int num_bsc; + int bsc_ip_dscp; + + /* MGCP config */ + struct mgcp_config *mgcp_cfg; + uint8_t mgcp_msg[4096]; + int mgcp_length; + + /* msc things */ + char *msc_ip; + int msc_port; + struct bsc_msc_connection *msc_con; + char *token; + + /* timeouts */ + int auth_timeout; + int ping_timeout; + int pong_timeout; + + struct bsc_endpoint *bsc_endpoints; + + /* filter */ + char *acc_lst_name; + + /* number rewriting */ + char *num_rewr_name; + struct msg_entries *num_rewr; + + /* USSD messages we want to match */ + char *ussd_lst_name; + char *ussd_query; + char *ussd_token; + char *ussd_local; + struct bsc_fd ussd_listen; + struct bsc_nat_ussd_con *ussd_con; + + /* statistics */ + struct bsc_nat_statistics stats; +}; + +/* create and init the structures */ +struct bsc_config *bsc_config_alloc(struct bsc_nat *nat, const char *token); +struct bsc_config *bsc_config_num(struct bsc_nat *nat, int num); +void bsc_config_free(struct bsc_config *); +void bsc_config_add_lac(struct bsc_config *cfg, int lac); +void bsc_config_del_lac(struct bsc_config *cfg, int lac); +int bsc_config_handles_lac(struct bsc_config *cfg, int lac); + +struct bsc_nat *bsc_nat_alloc(void); +struct bsc_connection *bsc_connection_alloc(struct bsc_nat *nat); +void bsc_nat_set_msc_ip(struct bsc_nat *bsc, const char *ip); + +void sccp_connection_destroy(struct sccp_connections *); +void bsc_close_connection(struct bsc_connection *); + +const char *bsc_con_type_to_string(int type); + +/** + * 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, int *_lac); + +/** + * Content filtering. + */ +int bsc_nat_filter_sccp_cr(struct bsc_connection *bsc, struct msgb *msg, + struct bsc_nat_parsed *, int *con_type, char **imsi); +int bsc_nat_filter_dt(struct bsc_connection *bsc, struct msgb *msg, + struct sccp_connections *con, struct bsc_nat_parsed *parsed); + +/** + * SCCP patching and handling + */ +struct sccp_connections *create_sccp_src_ref(struct bsc_connection *bsc, 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_connection *); +struct sccp_connections *bsc_nat_find_con_by_bsc(struct bsc_nat *, struct sccp_source_reference *); + +/** + * MGCP/Audio handling + */ +int bsc_mgcp_nr_multiplexes(int max_endpoints); +int bsc_write_mgcp(struct bsc_connection *bsc, const uint8_t *data, unsigned int length); +int bsc_mgcp_assign_patch(struct sccp_connections *, struct msgb *msg); +void bsc_mgcp_init(struct sccp_connections *); +void bsc_mgcp_dlcx(struct sccp_connections *); +void bsc_mgcp_free_endpoints(struct bsc_nat *nat); +int bsc_mgcp_nat_init(struct bsc_nat *nat); + +struct sccp_connections *bsc_mgcp_find_con(struct bsc_nat *, int endpoint_number); +struct msgb *bsc_mgcp_rewrite(char *input, int length, int endp, 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]); +uint32_t bsc_mgcp_extract_ci(const char *resp); + + +int bsc_write(struct bsc_connection *bsc, struct msgb *msg, int id); +int bsc_do_write(struct write_queue *queue, struct msgb *msg, int id); +int bsc_write_msg(struct write_queue *queue, struct msgb *msg); +int bsc_write_cb(struct bsc_fd *bfd, struct msgb *msg); + +/* IMSI allow/deny handling */ +void bsc_parse_reg(void *ctx, regex_t *reg, char **imsi, int argc, const char **argv); +struct bsc_nat_acc_lst *bsc_nat_acc_lst_find(struct bsc_nat *nat, const char *name); +struct bsc_nat_acc_lst *bsc_nat_acc_lst_get(struct bsc_nat *nat, const char *name); +void bsc_nat_acc_lst_delete(struct bsc_nat_acc_lst *lst); + +struct bsc_nat_acc_lst_entry *bsc_nat_acc_lst_entry_create(struct bsc_nat_acc_lst *); +int bsc_nat_lst_check_allow(struct bsc_nat_acc_lst *lst, const char *imsi); + +int bsc_nat_msc_is_connected(struct bsc_nat *nat); + +int bsc_conn_type_to_ctr(struct sccp_connections *conn); + +struct gsm48_hdr *bsc_unpack_dtap(struct bsc_nat_parsed *parsed, struct msgb *msg, uint32_t *len); + +/** USSD filtering */ +int bsc_ussd_init(struct bsc_nat *nat); +int bsc_check_ussd(struct sccp_connections *con, struct bsc_nat_parsed *parsed, struct msgb *msg); +int bsc_close_ussd_connections(struct bsc_nat *nat); + +struct msgb *bsc_nat_rewrite_setup(struct bsc_nat *nat, struct msgb *msg, struct bsc_nat_parsed *, const char *imsi); + +#endif |