1374 lines
35 KiB
C
1374 lines
35 KiB
C
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/* BSC Multiplexer/NAT Utilities */
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/*
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* (C) 2010-2011 by Holger Hans Peter Freyther <zecke@selfish.org>
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* (C) 2010-2011 by On-Waves
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* All Rights Reserved
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU Affero General Public License as published by
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* the Free Software Foundation; either version 3 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU Affero General Public License for more details.
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*
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* You should have received a copy of the GNU Affero General Public License
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* along with this program. If not, see <http://www.gnu.org/licenses/>.
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*
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*/
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#include <openbsc/bsc_nat.h>
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#include <openbsc/bsc_nat_sccp.h>
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#include <openbsc/bsc_msc.h>
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#include <openbsc/gsm_data.h>
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#include <openbsc/debug.h>
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#include <openbsc/ipaccess.h>
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#include <openbsc/vty.h>
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#include <osmocom/core/linuxlist.h>
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#include <osmocom/core/talloc.h>
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#include <osmocom/gsm/gsm0808.h>
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#include <osmocom/gsm/protocol/gsm_08_08.h>
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#include <osmocom/gsm/protocol/gsm_04_11.h>
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#include <osmocom/sccp/sccp.h>
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#include <netinet/in.h>
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#include <arpa/inet.h>
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#include <unistd.h>
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static const struct rate_ctr_desc bsc_cfg_ctr_description[] = {
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[BCFG_CTR_SCCP_CONN] = { "sccp.conn", "SCCP Connections "},
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[BCFG_CTR_SCCP_CALLS] = { "sccp.calls", "SCCP Assignment Commands "},
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[BCFG_CTR_NET_RECONN] = { "net.reconnects", "Network reconnects "},
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[BCFG_CTR_DROPPED_SCCP] = { "dropped.sccp", "Dropped SCCP connections."},
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[BCFG_CTR_DROPPED_CALLS] = { "dropped.calls", "Dropped active calls. "},
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[BCFG_CTR_REJECTED_CR] = { "rejected.cr", "Rejected CR due filter "},
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[BCFG_CTR_REJECTED_MSG] = { "rejected.msg", "Rejected MSG due filter "},
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[BCFG_CTR_ILL_PACKET] = { "rejected.ill", "Rejected due parse error "},
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[BCFG_CTR_CON_TYPE_LU] = { "conn.lu", "Conn Location Update "},
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[BCFG_CTR_CON_CMSERV_RQ] = { "conn.rq", "Conn CM Service Req "},
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[BCFG_CTR_CON_PAG_RESP] = { "conn.pag", "Conn Paging Response "},
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[BCFG_CTR_CON_SSA] = { "conn.ssa", "Conn USSD "},
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[BCFG_CTR_CON_OTHER] = { "conn.other", "Conn Other "},
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};
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static const struct rate_ctr_group_desc bsc_cfg_ctrg_desc = {
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.group_name_prefix = "nat.bsc",
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.group_description = "NAT BSC Statistics",
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.num_ctr = ARRAY_SIZE(bsc_cfg_ctr_description),
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.ctr_desc = bsc_cfg_ctr_description,
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};
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static const struct rate_ctr_desc acc_list_ctr_description[] = {
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[ACC_LIST_BSC_FILTER] = { "access-list.bsc-filter", "Rejected by rule for BSC"},
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[ACC_LIST_NAT_FILTER] = { "access-list.nat-filter", "Rejected by rule for NAT"},
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};
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static const struct rate_ctr_group_desc bsc_cfg_acc_list_desc = {
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.group_name_prefix = "nat.filter",
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.group_description = "NAT Access-List Statistics",
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.num_ctr = ARRAY_SIZE(acc_list_ctr_description),
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.ctr_desc = acc_list_ctr_description,
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};
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struct bsc_nat *bsc_nat_alloc(void)
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{
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struct bsc_nat *nat = talloc_zero(tall_bsc_ctx, struct bsc_nat);
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if (!nat)
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return NULL;
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nat->main_dest = talloc_zero(nat, struct bsc_msc_dest);
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if (!nat->main_dest) {
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talloc_free(nat);
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return NULL;
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}
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INIT_LLIST_HEAD(&nat->sccp_connections);
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INIT_LLIST_HEAD(&nat->bsc_connections);
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INIT_LLIST_HEAD(&nat->paging_groups);
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INIT_LLIST_HEAD(&nat->bsc_configs);
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INIT_LLIST_HEAD(&nat->access_lists);
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INIT_LLIST_HEAD(&nat->dests);
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INIT_LLIST_HEAD(&nat->num_rewr);
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INIT_LLIST_HEAD(&nat->smsc_rewr);
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INIT_LLIST_HEAD(&nat->tpdest_match);
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INIT_LLIST_HEAD(&nat->sms_clear_tp_srr);
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INIT_LLIST_HEAD(&nat->sms_num_rewr);
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nat->stats.sccp.conn = osmo_counter_alloc("nat.sccp.conn");
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nat->stats.sccp.calls = osmo_counter_alloc("nat.sccp.calls");
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nat->stats.bsc.reconn = osmo_counter_alloc("nat.bsc.conn");
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nat->stats.bsc.auth_fail = osmo_counter_alloc("nat.bsc.auth_fail");
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nat->stats.msc.reconn = osmo_counter_alloc("nat.msc.conn");
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nat->stats.ussd.reconn = osmo_counter_alloc("nat.ussd.conn");
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nat->auth_timeout = 2;
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nat->ping_timeout = 20;
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nat->pong_timeout = 5;
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llist_add(&nat->main_dest->list, &nat->dests);
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nat->main_dest->ip = talloc_strdup(nat, "127.0.0.1");
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nat->main_dest->port = 5000;
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return nat;
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}
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void bsc_nat_set_msc_ip(struct bsc_nat *nat, const char *ip)
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{
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bsc_replace_string(nat, &nat->main_dest->ip, ip);
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}
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struct bsc_connection *bsc_connection_alloc(struct bsc_nat *nat)
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{
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struct bsc_connection *con = talloc_zero(nat, struct bsc_connection);
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if (!con)
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return NULL;
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con->nat = nat;
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osmo_wqueue_init(&con->write_queue, 100);
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INIT_LLIST_HEAD(&con->cmd_pending);
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return con;
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}
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struct bsc_config *bsc_config_alloc(struct bsc_nat *nat, const char *token)
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{
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struct bsc_config *conf = talloc_zero(nat, struct bsc_config);
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if (!conf)
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return NULL;
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conf->token = talloc_strdup(conf, token);
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conf->nr = nat->num_bsc;
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conf->nat = nat;
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conf->max_endpoints = 32;
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conf->paging_group = PAGIN_GROUP_UNASSIGNED;
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INIT_LLIST_HEAD(&conf->lac_list);
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llist_add_tail(&conf->entry, &nat->bsc_configs);
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++nat->num_bsc;
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conf->stats.ctrg = rate_ctr_group_alloc(conf, &bsc_cfg_ctrg_desc, conf->nr);
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if (!conf->stats.ctrg) {
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talloc_free(conf);
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return NULL;
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}
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return conf;
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}
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void bsc_config_free(struct bsc_config *cfg)
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{
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rate_ctr_group_free(cfg->stats.ctrg);
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}
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static void _add_lac(void *ctx, struct llist_head *list, int _lac)
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{
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struct bsc_lac_entry *lac;
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llist_for_each_entry(lac, list, entry)
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if (lac->lac == _lac)
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return;
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lac = talloc_zero(ctx, struct bsc_lac_entry);
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if (!lac) {
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LOGP(DNAT, LOGL_ERROR, "Failed to allocate.\n");
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return;
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}
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lac->lac = _lac;
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llist_add_tail(&lac->entry, list);
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}
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static void _del_lac(struct llist_head *list, int _lac)
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{
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struct bsc_lac_entry *lac;
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llist_for_each_entry(lac, list, entry)
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if (lac->lac == _lac) {
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llist_del(&lac->entry);
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talloc_free(lac);
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return;
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}
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}
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void bsc_config_add_lac(struct bsc_config *cfg, int _lac)
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{
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_add_lac(cfg, &cfg->lac_list, _lac);
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}
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void bsc_config_del_lac(struct bsc_config *cfg, int _lac)
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{
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_del_lac(&cfg->lac_list, _lac);
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}
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struct bsc_nat_paging_group *bsc_nat_paging_group_create(struct bsc_nat *nat, int group)
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{
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struct bsc_nat_paging_group *pgroup;
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pgroup = talloc_zero(nat, struct bsc_nat_paging_group);
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if (!pgroup) {
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LOGP(DNAT, LOGL_ERROR, "Failed to allocate a paging group.\n");
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return NULL;
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}
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pgroup->nr = group;
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INIT_LLIST_HEAD(&pgroup->lists);
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llist_add_tail(&pgroup->entry, &nat->paging_groups);
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return pgroup;
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}
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void bsc_nat_paging_group_delete(struct bsc_nat_paging_group *pgroup)
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{
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llist_del(&pgroup->entry);
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talloc_free(pgroup);
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}
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struct bsc_nat_paging_group *bsc_nat_paging_group_num(struct bsc_nat *nat, int group)
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{
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struct bsc_nat_paging_group *pgroup;
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llist_for_each_entry(pgroup, &nat->paging_groups, entry)
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if (pgroup->nr == group)
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return pgroup;
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return NULL;
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}
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void bsc_nat_paging_group_add_lac(struct bsc_nat_paging_group *pgroup, int lac)
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{
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_add_lac(pgroup, &pgroup->lists, lac);
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}
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void bsc_nat_paging_group_del_lac(struct bsc_nat_paging_group *pgroup, int lac)
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{
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_del_lac(&pgroup->lists, lac);
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}
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int bsc_config_handles_lac(struct bsc_config *cfg, int lac_nr)
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{
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struct bsc_nat_paging_group *pgroup;
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struct bsc_lac_entry *entry;
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llist_for_each_entry(entry, &cfg->lac_list, entry)
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if (entry->lac == lac_nr)
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return 1;
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/* now lookup the paging group */
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pgroup = bsc_nat_paging_group_num(cfg->nat, cfg->paging_group);
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if (!pgroup)
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return 0;
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llist_for_each_entry(entry, &pgroup->lists, entry)
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if (entry->lac == lac_nr)
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return 1;
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return 0;
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}
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void sccp_connection_destroy(struct sccp_connections *conn)
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{
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LOGP(DNAT, LOGL_DEBUG, "Destroy 0x%x <-> 0x%x mapping for con %p\n",
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sccp_src_ref_to_int(&conn->real_ref),
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sccp_src_ref_to_int(&conn->patched_ref), conn->bsc);
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bsc_mgcp_dlcx(conn);
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llist_del(&conn->list_entry);
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talloc_free(conn);
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}
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int bsc_nat_find_paging(struct msgb *msg,
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const uint8_t **out_data, int *out_leng)
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{
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int data_length;
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const uint8_t *data;
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struct tlv_parsed tp;
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if (!msg->l3h || msgb_l3len(msg) < 3) {
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LOGP(DNAT, LOGL_ERROR, "Paging message is too short.\n");
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return -1;
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}
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tlv_parse(&tp, gsm0808_att_tlvdef(), msg->l3h + 3, msgb_l3len(msg) - 3, 0, 0);
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if (!TLVP_PRESENT(&tp, GSM0808_IE_CELL_IDENTIFIER_LIST)) {
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LOGP(DNAT, LOGL_ERROR, "No CellIdentifier List inside paging msg.\n");
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return -2;
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}
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data_length = TLVP_LEN(&tp, GSM0808_IE_CELL_IDENTIFIER_LIST);
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data = TLVP_VAL(&tp, GSM0808_IE_CELL_IDENTIFIER_LIST);
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/* No need to try a different BSS */
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if (data[0] == CELL_IDENT_BSS) {
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return -3;
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} else if (data[0] != CELL_IDENT_LAC) {
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LOGP(DNAT, LOGL_ERROR, "Unhandled cell ident discrminator: %d\n", data[0]);
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return -4;
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}
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*out_data = &data[1];
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*out_leng = data_length - 1;
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return 0;
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}
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int bsc_write_mgcp(struct bsc_connection *bsc, const uint8_t *data, unsigned int length)
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{
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struct msgb *msg;
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if (length > 4096 - 128) {
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LOGP(DLINP, LOGL_ERROR, "Can not send message of that size.\n");
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return -1;
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}
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msg = msgb_alloc_headroom(4096, 128, "to-bsc");
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if (!msg) {
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LOGP(DLINP, LOGL_ERROR, "Failed to allocate memory for BSC msg.\n");
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return -1;
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}
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/* copy the data */
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msg->l3h = msgb_put(msg, length);
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memcpy(msg->l3h, data, length);
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return bsc_write(bsc, msg, IPAC_PROTO_MGCP_OLD);
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}
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int bsc_write(struct bsc_connection *bsc, struct msgb *msg, int proto)
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{
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return bsc_do_write(&bsc->write_queue, msg, proto);
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}
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int bsc_do_write(struct osmo_wqueue *queue, struct msgb *msg, int proto)
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{
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/* prepend the header */
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ipaccess_prepend_header(msg, proto);
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return bsc_write_msg(queue, msg);
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}
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int bsc_write_msg(struct osmo_wqueue *queue, struct msgb *msg)
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{
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if (osmo_wqueue_enqueue(queue, msg) != 0) {
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LOGP(DLINP, LOGL_ERROR, "Failed to enqueue the write.\n");
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msgb_free(msg);
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return -1;
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}
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return 0;
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}
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int bsc_nat_lst_check_allow(struct bsc_nat_acc_lst *lst, const char *mi_string)
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{
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struct bsc_nat_acc_lst_entry *entry;
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llist_for_each_entry(entry, &lst->fltr_list, list) {
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if (!entry->imsi_allow)
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continue;
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if (regexec(&entry->imsi_allow_re, mi_string, 0, NULL, 0) == 0)
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return 0;
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}
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return 1;
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}
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static int lst_check_deny(struct bsc_nat_acc_lst *lst, const char *mi_string)
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{
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struct bsc_nat_acc_lst_entry *entry;
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llist_for_each_entry(entry, &lst->fltr_list, list) {
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if (!entry->imsi_deny)
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continue;
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if (regexec(&entry->imsi_deny_re, mi_string, 0, NULL, 0) == 0)
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return 0;
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}
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return 1;
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}
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/* apply white/black list */
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static int auth_imsi(struct bsc_connection *bsc, const char *mi_string)
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{
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/*
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* Now apply blacklist/whitelist of the BSC and the NAT.
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* 1.) Allow directly if the IMSI is allowed at the BSC
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* 2.) Reject if the IMSI is not allowed at the BSC
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* 3.) Reject if the IMSI not allowed at the global level.
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* 4.) Allow directly if the IMSI is allowed at the global level
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*/
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struct bsc_nat_acc_lst *nat_lst = NULL;
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struct bsc_nat_acc_lst *bsc_lst = NULL;
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bsc_lst = bsc_nat_acc_lst_find(bsc->nat, bsc->cfg->acc_lst_name);
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nat_lst = bsc_nat_acc_lst_find(bsc->nat, bsc->nat->acc_lst_name);
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if (bsc_lst) {
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/* 1. BSC allow */
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if (bsc_nat_lst_check_allow(bsc_lst, mi_string) == 0)
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return 1;
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/* 2. BSC deny */
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if (lst_check_deny(bsc_lst, mi_string) == 0) {
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LOGP(DNAT, LOGL_ERROR,
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"Filtering %s by imsi_deny on bsc nr: %d.\n", mi_string, bsc->cfg->nr);
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rate_ctr_inc(&bsc_lst->stats->ctr[ACC_LIST_BSC_FILTER]);
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return -2;
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}
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}
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/* 3. NAT deny */
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if (nat_lst) {
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if (lst_check_deny(nat_lst, mi_string) == 0) {
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LOGP(DNAT, LOGL_ERROR,
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"Filtering %s by nat imsi_deny on bsc nr: %d.\n", mi_string, bsc->cfg->nr);
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rate_ctr_inc(&nat_lst->stats->ctr[ACC_LIST_NAT_FILTER]);
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return -3;
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}
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}
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return 1;
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}
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static int _cr_check_loc_upd(struct bsc_connection *bsc,
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uint8_t *data, unsigned int length,
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char **imsi)
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{
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uint8_t mi_type;
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struct gsm48_loc_upd_req *lu;
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char mi_string[GSM48_MI_SIZE];
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if (length < sizeof(*lu)) {
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LOGP(DNAT, LOGL_ERROR,
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"LU does not fit. Length is %d \n", length);
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return -1;
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}
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lu = (struct gsm48_loc_upd_req *) data;
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mi_type = lu->mi[0] & GSM_MI_TYPE_MASK;
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/*
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* We can only deal with the IMSI. This will fail for a phone that
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* will send the TMSI of a previous network to us.
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*/
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if (mi_type != GSM_MI_TYPE_IMSI)
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return 0;
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gsm48_mi_to_string(mi_string, sizeof(mi_string), lu->mi, lu->mi_len);
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*imsi = talloc_strdup(bsc, mi_string);
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return auth_imsi(bsc, mi_string);
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}
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static int _cr_check_cm_serv_req(struct bsc_connection *bsc,
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|
uint8_t *data, unsigned int length,
|
|
int *con_type, char **imsi)
|
|
{
|
|
static const uint32_t classmark_offset =
|
|
offsetof(struct gsm48_service_request, classmark);
|
|
|
|
char mi_string[GSM48_MI_SIZE];
|
|
uint8_t mi_type;
|
|
int rc;
|
|
struct gsm48_service_request *req;
|
|
|
|
/* unfortunately in Phase1 the classmark2 length is variable */
|
|
|
|
if (length < sizeof(*req)) {
|
|
LOGP(DNAT, LOGL_ERROR,
|
|
"CM Serv Req does not fit. Length is %d\n", length);
|
|
return -1;
|
|
}
|
|
|
|
req = (struct gsm48_service_request *) data;
|
|
if (req->cm_service_type == 0x8)
|
|
*con_type = NAT_CON_TYPE_SSA;
|
|
rc = gsm48_extract_mi((uint8_t *) &req->classmark,
|
|
length - classmark_offset, mi_string, &mi_type);
|
|
if (rc < 0) {
|
|
LOGP(DNAT, LOGL_ERROR, "Failed to parse the classmark2/mi. error: %d\n", rc);
|
|
return -1;
|
|
}
|
|
|
|
/* we have to let the TMSI or such pass */
|
|
if (mi_type != GSM_MI_TYPE_IMSI)
|
|
return 0;
|
|
|
|
*imsi = talloc_strdup(bsc, mi_string);
|
|
return auth_imsi(bsc, mi_string);
|
|
}
|
|
|
|
static int _cr_check_pag_resp(struct bsc_connection *bsc,
|
|
uint8_t *data, unsigned int length,
|
|
char **imsi)
|
|
{
|
|
struct gsm48_pag_resp *resp;
|
|
char mi_string[GSM48_MI_SIZE];
|
|
uint8_t mi_type;
|
|
|
|
if (length < sizeof(*resp)) {
|
|
LOGP(DNAT, LOGL_ERROR, "PAG RESP does not fit. Length was %d.\n", length);
|
|
return -1;
|
|
}
|
|
|
|
resp = (struct gsm48_pag_resp *) data;
|
|
if (gsm48_paging_extract_mi(resp, length, mi_string, &mi_type) < 0) {
|
|
LOGP(DNAT, LOGL_ERROR, "Failed to extract the MI.\n");
|
|
return -1;
|
|
}
|
|
|
|
/* we need to let it pass for now */
|
|
if (mi_type != GSM_MI_TYPE_IMSI)
|
|
return 0;
|
|
|
|
*imsi = talloc_strdup(bsc, mi_string);
|
|
return auth_imsi(bsc, mi_string);
|
|
}
|
|
|
|
static int _dt_check_id_resp(struct bsc_connection *bsc,
|
|
uint8_t *data, unsigned int length,
|
|
struct sccp_connections *con)
|
|
{
|
|
char mi_string[GSM48_MI_SIZE];
|
|
uint8_t mi_type;
|
|
int ret;
|
|
|
|
if (length < 2) {
|
|
LOGP(DNAT, LOGL_ERROR, "mi does not fit.\n");
|
|
return -1;
|
|
}
|
|
|
|
if (data[0] < length - 1) {
|
|
LOGP(DNAT, LOGL_ERROR, "mi length too big.\n");
|
|
return -2;
|
|
}
|
|
|
|
mi_type = data[1] & GSM_MI_TYPE_MASK;
|
|
gsm48_mi_to_string(mi_string, sizeof(mi_string), &data[1], data[0]);
|
|
|
|
if (mi_type != GSM_MI_TYPE_IMSI)
|
|
return 0;
|
|
|
|
ret = auth_imsi(bsc, mi_string);
|
|
con->imsi_checked = 1;
|
|
con->imsi = talloc_strdup(con, mi_string);
|
|
return ret;
|
|
}
|
|
|
|
/* Filter out CR data... */
|
|
int bsc_nat_filter_sccp_cr(struct bsc_connection *bsc, struct msgb *msg,
|
|
struct bsc_nat_parsed *parsed, int *con_type,
|
|
char **imsi)
|
|
{
|
|
struct tlv_parsed tp;
|
|
struct gsm48_hdr *hdr48;
|
|
int hdr48_len;
|
|
int len;
|
|
uint8_t msg_type, proto;
|
|
|
|
*con_type = NAT_CON_TYPE_NONE;
|
|
*imsi = NULL;
|
|
|
|
if (parsed->gsm_type != BSS_MAP_MSG_COMPLETE_LAYER_3) {
|
|
LOGP(DNAT, LOGL_ERROR,
|
|
"Rejecting CR message due wrong GSM Type %d\n", parsed->gsm_type);
|
|
return -1;
|
|
}
|
|
|
|
/* the parsed has had some basic l3 length check */
|
|
len = msg->l3h[1];
|
|
if (msgb_l3len(msg) - 3 < len) {
|
|
LOGP(DNAT, LOGL_ERROR,
|
|
"The CR Data has not enough space...\n");
|
|
return -1;
|
|
}
|
|
|
|
msg->l4h = &msg->l3h[3];
|
|
len -= 1;
|
|
|
|
tlv_parse(&tp, gsm0808_att_tlvdef(), msg->l4h, len, 0, 0);
|
|
|
|
if (!TLVP_PRESENT(&tp, GSM0808_IE_LAYER_3_INFORMATION)) {
|
|
LOGP(DNAT, LOGL_ERROR, "CR Data does not contain layer3 information.\n");
|
|
return -1;
|
|
}
|
|
|
|
hdr48_len = TLVP_LEN(&tp, GSM0808_IE_LAYER_3_INFORMATION);
|
|
|
|
if (hdr48_len < sizeof(*hdr48)) {
|
|
LOGP(DNAT, LOGL_ERROR, "GSM48 header does not fit.\n");
|
|
return -1;
|
|
}
|
|
|
|
hdr48 = (struct gsm48_hdr *) TLVP_VAL(&tp, GSM0808_IE_LAYER_3_INFORMATION);
|
|
|
|
proto = hdr48->proto_discr & 0x0f;
|
|
msg_type = hdr48->msg_type & 0xbf;
|
|
if (proto == GSM48_PDISC_MM &&
|
|
msg_type == GSM48_MT_MM_LOC_UPD_REQUEST) {
|
|
*con_type = NAT_CON_TYPE_LU;
|
|
return _cr_check_loc_upd(bsc, &hdr48->data[0], hdr48_len - sizeof(*hdr48), imsi);
|
|
} else if (proto == GSM48_PDISC_MM &&
|
|
msg_type == GSM48_MT_MM_CM_SERV_REQ) {
|
|
*con_type = NAT_CON_TYPE_CM_SERV_REQ;
|
|
return _cr_check_cm_serv_req(bsc, &hdr48->data[0],
|
|
hdr48_len - sizeof(*hdr48),
|
|
con_type, imsi);
|
|
} else if (proto == GSM48_PDISC_RR &&
|
|
msg_type == GSM48_MT_RR_PAG_RESP) {
|
|
*con_type = NAT_CON_TYPE_PAG_RESP;
|
|
return _cr_check_pag_resp(bsc, &hdr48->data[0], hdr48_len - sizeof(*hdr48), imsi);
|
|
} else {
|
|
/* We only want to filter the above, let other things pass */
|
|
*con_type = NAT_CON_TYPE_OTHER;
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
struct gsm48_hdr *bsc_unpack_dtap(struct bsc_nat_parsed *parsed,
|
|
struct msgb *msg, uint32_t *len)
|
|
{
|
|
/* gsm_type is actually the size of the dtap */
|
|
*len = parsed->gsm_type;
|
|
if (*len < msgb_l3len(msg) - 3) {
|
|
LOGP(DNAT, LOGL_ERROR, "Not enough space for DTAP.\n");
|
|
return NULL;
|
|
}
|
|
|
|
if (msgb_l3len(msg) - 3 < msg->l3h[2]) {
|
|
LOGP(DNAT, LOGL_ERROR,
|
|
"GSM48 payload does not fit: %d %d\n",
|
|
msg->l3h[2], msgb_l3len(msg) - 3);
|
|
return NULL;
|
|
}
|
|
|
|
msg->l4h = &msg->l3h[3];
|
|
return (struct gsm48_hdr *) msg->l4h;
|
|
}
|
|
|
|
int bsc_nat_filter_dt(struct bsc_connection *bsc, struct msgb *msg,
|
|
struct sccp_connections *con, struct bsc_nat_parsed *parsed)
|
|
{
|
|
uint32_t len;
|
|
uint8_t msg_type, proto;
|
|
struct gsm48_hdr *hdr48;
|
|
|
|
if (con->imsi_checked)
|
|
return 0;
|
|
|
|
/* only care about DTAP messages */
|
|
if (parsed->bssap != BSSAP_MSG_DTAP)
|
|
return 0;
|
|
|
|
hdr48 = bsc_unpack_dtap(parsed, msg, &len);
|
|
if (!hdr48)
|
|
return -1;
|
|
|
|
proto = hdr48->proto_discr & 0x0f;
|
|
msg_type = hdr48->msg_type & 0xbf;
|
|
if (proto == GSM48_PDISC_MM &&
|
|
msg_type == GSM48_MT_MM_ID_RESP) {
|
|
return _dt_check_id_resp(bsc, &hdr48->data[0], len - sizeof(*hdr48), con);
|
|
} else {
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
static const char *con_types [] = {
|
|
[NAT_CON_TYPE_NONE] = "n/a",
|
|
[NAT_CON_TYPE_LU] = "Location Update",
|
|
[NAT_CON_TYPE_CM_SERV_REQ] = "CM Serv Req",
|
|
[NAT_CON_TYPE_PAG_RESP] = "Paging Response",
|
|
[NAT_CON_TYPE_SSA] = "Supplementar Service Activation",
|
|
[NAT_CON_TYPE_LOCAL_REJECT] = "Local Reject",
|
|
[NAT_CON_TYPE_OTHER] = "Other",
|
|
};
|
|
|
|
const char *bsc_con_type_to_string(int type)
|
|
{
|
|
return con_types[type];
|
|
}
|
|
|
|
struct bsc_nat_acc_lst *bsc_nat_acc_lst_find(struct bsc_nat *nat, const char *name)
|
|
{
|
|
struct bsc_nat_acc_lst *lst;
|
|
|
|
if (!name)
|
|
return NULL;
|
|
|
|
llist_for_each_entry(lst, &nat->access_lists, list)
|
|
if (strcmp(lst->name, name) == 0)
|
|
return lst;
|
|
|
|
return NULL;
|
|
}
|
|
|
|
struct bsc_nat_acc_lst *bsc_nat_acc_lst_get(struct bsc_nat *nat, const char *name)
|
|
{
|
|
struct bsc_nat_acc_lst *lst;
|
|
|
|
lst = bsc_nat_acc_lst_find(nat, name);
|
|
if (lst)
|
|
return lst;
|
|
|
|
lst = talloc_zero(nat, struct bsc_nat_acc_lst);
|
|
if (!lst) {
|
|
LOGP(DNAT, LOGL_ERROR, "Failed to allocate access list");
|
|
return NULL;
|
|
}
|
|
|
|
/* TODO: get the index right */
|
|
lst->stats = rate_ctr_group_alloc(lst, &bsc_cfg_acc_list_desc, 0);
|
|
if (!lst->stats) {
|
|
talloc_free(lst);
|
|
return NULL;
|
|
}
|
|
|
|
INIT_LLIST_HEAD(&lst->fltr_list);
|
|
lst->name = talloc_strdup(lst, name);
|
|
llist_add_tail(&lst->list, &nat->access_lists);
|
|
return lst;
|
|
}
|
|
|
|
void bsc_nat_acc_lst_delete(struct bsc_nat_acc_lst *lst)
|
|
{
|
|
llist_del(&lst->list);
|
|
rate_ctr_group_free(lst->stats);
|
|
talloc_free(lst);
|
|
}
|
|
|
|
struct bsc_nat_acc_lst_entry *bsc_nat_acc_lst_entry_create(struct bsc_nat_acc_lst *lst)
|
|
{
|
|
struct bsc_nat_acc_lst_entry *entry;
|
|
|
|
entry = talloc_zero(lst, struct bsc_nat_acc_lst_entry);
|
|
if (!entry)
|
|
return NULL;
|
|
|
|
llist_add_tail(&entry->list, &lst->fltr_list);
|
|
return entry;
|
|
}
|
|
|
|
int bsc_nat_msc_is_connected(struct bsc_nat *nat)
|
|
{
|
|
return nat->msc_con->is_connected;
|
|
}
|
|
|
|
static const int con_to_ctr[] = {
|
|
[NAT_CON_TYPE_NONE] = -1,
|
|
[NAT_CON_TYPE_LU] = BCFG_CTR_CON_TYPE_LU,
|
|
[NAT_CON_TYPE_CM_SERV_REQ] = BCFG_CTR_CON_CMSERV_RQ,
|
|
[NAT_CON_TYPE_PAG_RESP] = BCFG_CTR_CON_PAG_RESP,
|
|
[NAT_CON_TYPE_SSA] = BCFG_CTR_CON_SSA,
|
|
[NAT_CON_TYPE_LOCAL_REJECT] = -1,
|
|
[NAT_CON_TYPE_OTHER] = BCFG_CTR_CON_OTHER,
|
|
};
|
|
|
|
int bsc_conn_type_to_ctr(struct sccp_connections *conn)
|
|
{
|
|
return con_to_ctr[conn->con_type];
|
|
}
|
|
|
|
int bsc_write_cb(struct osmo_fd *bfd, struct msgb *msg)
|
|
{
|
|
int rc;
|
|
|
|
rc = write(bfd->fd, msg->data, msg->len);
|
|
if (rc != msg->len)
|
|
LOGP(DNAT, LOGL_ERROR, "Failed to write message to the BSC.\n");
|
|
|
|
return rc;
|
|
}
|
|
|
|
static char *match_and_rewrite_number(void *ctx, const char *number,
|
|
const char *imsi,
|
|
struct llist_head *list)
|
|
{
|
|
struct bsc_nat_num_rewr_entry *entry;
|
|
char *new_number = NULL;
|
|
|
|
/* need to find a replacement and then fix it */
|
|
llist_for_each_entry(entry, list, list) {
|
|
regmatch_t matches[2];
|
|
|
|
/* check the IMSI match */
|
|
if (regexec(&entry->msisdn_reg, imsi, 0, NULL, 0) != 0)
|
|
continue;
|
|
|
|
/* this regexp matches... */
|
|
if (regexec(&entry->num_reg, number, 2, matches, 0) == 0 &&
|
|
matches[1].rm_eo != -1)
|
|
new_number = talloc_asprintf(ctx, "%s%s",
|
|
entry->replace,
|
|
&number[matches[1].rm_so]);
|
|
if (new_number)
|
|
break;
|
|
}
|
|
|
|
return new_number;
|
|
}
|
|
|
|
static char *rewrite_non_international(struct bsc_nat *nat, void *ctx, const char *imsi,
|
|
struct gsm_mncc_number *called)
|
|
{
|
|
if (llist_empty(&nat->num_rewr))
|
|
return NULL;
|
|
|
|
if (called->plan != 1)
|
|
return NULL;
|
|
if (called->type == 1)
|
|
return NULL;
|
|
|
|
return match_and_rewrite_number(ctx, called->number,
|
|
imsi, &nat->num_rewr);
|
|
}
|
|
|
|
|
|
/**
|
|
* Rewrite non global numbers... according to rules based on the IMSI
|
|
*/
|
|
static struct msgb *rewrite_setup(struct bsc_nat *nat, struct msgb *msg,
|
|
struct bsc_nat_parsed *parsed, const char *imsi,
|
|
struct gsm48_hdr *hdr48, const uint32_t len)
|
|
{
|
|
struct tlv_parsed tp;
|
|
unsigned int payload_len;
|
|
struct gsm_mncc_number called;
|
|
struct msgb *out;
|
|
char *new_number = NULL;
|
|
uint8_t *outptr;
|
|
const uint8_t *msgptr;
|
|
int sec_len;
|
|
|
|
/* decode and rewrite the message */
|
|
payload_len = len - sizeof(*hdr48);
|
|
tlv_parse(&tp, &gsm48_att_tlvdef, hdr48->data, payload_len, 0, 0);
|
|
|
|
/* no number, well let us ignore it */
|
|
if (!TLVP_PRESENT(&tp, GSM48_IE_CALLED_BCD))
|
|
return NULL;
|
|
|
|
memset(&called, 0, sizeof(called));
|
|
gsm48_decode_called(&called,
|
|
TLVP_VAL(&tp, GSM48_IE_CALLED_BCD) - 1);
|
|
|
|
/* check if it looks international and stop */
|
|
new_number = rewrite_non_international(nat, msg, imsi, &called);
|
|
|
|
if (!new_number) {
|
|
LOGP(DNAT, LOGL_DEBUG, "No IMSI match found, returning message.\n");
|
|
return NULL;
|
|
}
|
|
|
|
if (strlen(new_number) > sizeof(called.number)) {
|
|
LOGP(DNAT, LOGL_ERROR, "Number is too long for structure.\n");
|
|
talloc_free(new_number);
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* Need to create a new message now based on the old onew
|
|
* with a new number. We can sadly not patch this in place
|
|
* so we will need to regenerate it.
|
|
*/
|
|
|
|
out = msgb_alloc_headroom(4096, 128, "changed-setup");
|
|
if (!out) {
|
|
LOGP(DNAT, LOGL_ERROR, "Failed to allocate.\n");
|
|
talloc_free(new_number);
|
|
return NULL;
|
|
}
|
|
|
|
/* copy the header */
|
|
outptr = msgb_put(out, sizeof(*hdr48));
|
|
memcpy(outptr, hdr48, sizeof(*hdr48));
|
|
|
|
/* copy everything up to the number */
|
|
sec_len = TLVP_VAL(&tp, GSM48_IE_CALLED_BCD) - 2 - &hdr48->data[0];
|
|
outptr = msgb_put(out, sec_len);
|
|
memcpy(outptr, &hdr48->data[0], sec_len);
|
|
|
|
/* create the new number */
|
|
if (strncmp(new_number, "00", 2) == 0) {
|
|
called.type = 1;
|
|
strncpy(called.number, new_number + 2, sizeof(called.number));
|
|
} else {
|
|
strncpy(called.number, new_number, sizeof(called.number));
|
|
}
|
|
gsm48_encode_called(out, &called);
|
|
|
|
/* copy thre rest */
|
|
msgptr = TLVP_VAL(&tp, GSM48_IE_CALLED_BCD) +
|
|
TLVP_LEN(&tp, GSM48_IE_CALLED_BCD);
|
|
sec_len = payload_len - (msgptr - &hdr48->data[0]);
|
|
outptr = msgb_put(out, sec_len);
|
|
memcpy(outptr, msgptr, sec_len);
|
|
|
|
talloc_free(new_number);
|
|
return out;
|
|
}
|
|
|
|
/**
|
|
* Find a new SMSC address, returns an allocated string that needs to be
|
|
* freed or is NULL.
|
|
*/
|
|
static char *find_new_smsc(struct bsc_nat *nat, void *ctx, const char *imsi,
|
|
const char *smsc_addr, const char *dest_nr)
|
|
{
|
|
struct bsc_nat_num_rewr_entry *entry;
|
|
char *new_number = NULL;
|
|
uint8_t dest_match = llist_empty(&nat->tpdest_match);
|
|
|
|
/* We will find a new number now */
|
|
llist_for_each_entry(entry, &nat->smsc_rewr, list) {
|
|
regmatch_t matches[2];
|
|
|
|
/* check the IMSI match */
|
|
if (regexec(&entry->msisdn_reg, imsi, 0, NULL, 0) != 0)
|
|
continue;
|
|
|
|
/* this regexp matches... */
|
|
if (regexec(&entry->num_reg, smsc_addr, 2, matches, 0) == 0 &&
|
|
matches[1].rm_eo != -1)
|
|
new_number = talloc_asprintf(ctx, "%s%s",
|
|
entry->replace,
|
|
&smsc_addr[matches[1].rm_so]);
|
|
if (new_number)
|
|
break;
|
|
}
|
|
|
|
if (!new_number)
|
|
return NULL;
|
|
|
|
/*
|
|
* now match the number against another list
|
|
*/
|
|
llist_for_each_entry(entry, &nat->tpdest_match, list) {
|
|
/* check the IMSI match */
|
|
if (regexec(&entry->msisdn_reg, imsi, 0, NULL, 0) != 0)
|
|
continue;
|
|
|
|
if (regexec(&entry->num_reg, dest_nr, 0, NULL, 0) == 0) {
|
|
dest_match = 1;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (!dest_match) {
|
|
talloc_free(new_number);
|
|
return NULL;
|
|
}
|
|
|
|
return new_number;
|
|
}
|
|
|
|
/**
|
|
* Clear the TP-SRR from the TPDU header
|
|
*/
|
|
static uint8_t sms_new_tpdu_hdr(struct bsc_nat *nat, const char *imsi,
|
|
const char *dest_nr, uint8_t hdr)
|
|
{
|
|
struct bsc_nat_num_rewr_entry *entry;
|
|
|
|
/* We will find a new number now */
|
|
llist_for_each_entry(entry, &nat->sms_clear_tp_srr, list) {
|
|
/* check the IMSI match */
|
|
if (regexec(&entry->msisdn_reg, imsi, 0, NULL, 0) != 0)
|
|
continue;
|
|
if (regexec(&entry->num_reg, dest_nr, 0, NULL, 0) != 0)
|
|
continue;
|
|
|
|
/* matched phone number and imsi */
|
|
return hdr & ~0x20;
|
|
}
|
|
|
|
return hdr;
|
|
}
|
|
|
|
/**
|
|
* Check if we need to rewrite the number. For this SMS.
|
|
*/
|
|
static char *sms_new_dest_nr(struct bsc_nat *nat, void *ctx,
|
|
const char *imsi, const char *dest_nr)
|
|
{
|
|
return match_and_rewrite_number(ctx, dest_nr, imsi,
|
|
&nat->sms_num_rewr);
|
|
}
|
|
|
|
/**
|
|
* This is a helper for GSM 04.11 8.2.5.2 Destination address element
|
|
*/
|
|
void sms_encode_addr_element(struct msgb *out, const char *new_number,
|
|
int format, int tp_data)
|
|
{
|
|
uint8_t new_addr_len;
|
|
uint8_t new_addr[26];
|
|
|
|
/*
|
|
* Copy the new number. We let libosmocore encode it, then set
|
|
* the extension followed after the length. Depending on if
|
|
* we want to write RP we will let the TLV code add the
|
|
* length for us or we need to use strlen... This is not very clear
|
|
* as of 03.40 and 04.11.
|
|
*/
|
|
new_addr_len = gsm48_encode_bcd_number(new_addr, ARRAY_SIZE(new_addr),
|
|
1, new_number);
|
|
new_addr[1] = format;
|
|
if (tp_data) {
|
|
uint8_t *data = msgb_put(out, new_addr_len);
|
|
memcpy(data, new_addr, new_addr_len);
|
|
data[0] = strlen(new_number);
|
|
} else {
|
|
msgb_lv_put(out, new_addr_len - 1, new_addr + 1);
|
|
}
|
|
}
|
|
|
|
static struct msgb *sms_create_new(uint8_t type, uint8_t ref,
|
|
struct gsm48_hdr *old_hdr48,
|
|
const uint8_t *orig_addr_ptr,
|
|
int orig_addr_len, const char *new_number,
|
|
const uint8_t *data_ptr, int data_len,
|
|
uint8_t tpdu_first_byte,
|
|
const int old_dest_len, const char *new_dest_nr)
|
|
{
|
|
struct gsm48_hdr *new_hdr48;
|
|
struct msgb *out;
|
|
|
|
/*
|
|
* We need to re-create the patched structure. This is why we have
|
|
* saved the above pointers.
|
|
*/
|
|
out = msgb_alloc_headroom(4096, 128, "changed-smsc");
|
|
if (!out) {
|
|
LOGP(DNAT, LOGL_ERROR, "Failed to allocate.\n");
|
|
return NULL;
|
|
}
|
|
|
|
out->l2h = out->data;
|
|
msgb_v_put(out, GSM411_MT_RP_DATA_MO);
|
|
msgb_v_put(out, ref);
|
|
msgb_lv_put(out, orig_addr_len, orig_addr_ptr);
|
|
|
|
sms_encode_addr_element(out, new_number, 0x91, 0);
|
|
|
|
|
|
/* Patch the TPDU from here on */
|
|
|
|
/**
|
|
* Do we need to put a new TP-Destination-Address (TP-DA) here or
|
|
* can we copy the old thing? For the TP-DA we need to find out the
|
|
* new size.
|
|
*/
|
|
if (new_dest_nr) {
|
|
uint8_t *data, *new_size;
|
|
|
|
/* reserve the size and write the header */
|
|
new_size = msgb_put(out, 1);
|
|
out->l3h = new_size + 1;
|
|
msgb_v_put(out, tpdu_first_byte);
|
|
msgb_v_put(out, data_ptr[1]);
|
|
|
|
/* encode the new number and put it */
|
|
if (strncmp(new_dest_nr, "00", 2) == 0)
|
|
sms_encode_addr_element(out, new_dest_nr + 2, 0x91, 1);
|
|
else
|
|
sms_encode_addr_element(out, new_dest_nr, 0x81, 1);
|
|
|
|
/* Copy the rest after the TP-DS */
|
|
data = msgb_put(out, data_len - 2 - 1 - old_dest_len);
|
|
memcpy(data, &data_ptr[2 + 1 + old_dest_len], data_len - 2 - 1 - old_dest_len);
|
|
|
|
/* fill in the new size */
|
|
new_size[0] = msgb_l3len(out);
|
|
} else {
|
|
msgb_v_put(out, data_len);
|
|
msgb_tv_fixed_put(out, tpdu_first_byte, data_len - 1, &data_ptr[1]);
|
|
}
|
|
|
|
/* prepend GSM 04.08 header */
|
|
new_hdr48 = (struct gsm48_hdr *) msgb_push(out, sizeof(*new_hdr48) + 1);
|
|
memcpy(new_hdr48, old_hdr48, sizeof(*old_hdr48));
|
|
new_hdr48->data[0] = msgb_l2len(out);
|
|
|
|
return out;
|
|
}
|
|
|
|
/**
|
|
* Parse the SMS and check if it needs to be rewritten
|
|
*/
|
|
static struct msgb *rewrite_sms(struct bsc_nat *nat, struct msgb *msg,
|
|
struct bsc_nat_parsed *parsed, const char *imsi,
|
|
struct gsm48_hdr *hdr48, const uint32_t len)
|
|
{
|
|
unsigned int payload_len;
|
|
unsigned int cp_len;
|
|
|
|
uint8_t ref;
|
|
uint8_t orig_addr_len, *orig_addr_ptr;
|
|
uint8_t dest_addr_len, *dest_addr_ptr;
|
|
uint8_t data_len, *data_ptr;
|
|
char smsc_addr[30];
|
|
|
|
|
|
uint8_t dest_len, orig_dest_len;
|
|
char _dest_nr[30];
|
|
char *dest_nr;
|
|
char *new_dest_nr;
|
|
|
|
char *new_number = NULL;
|
|
uint8_t tpdu_hdr;
|
|
struct msgb *out;
|
|
|
|
payload_len = len - sizeof(*hdr48);
|
|
if (payload_len < 1) {
|
|
LOGP(DNAT, LOGL_ERROR, "SMS too short for things. %d\n", payload_len);
|
|
return NULL;
|
|
}
|
|
|
|
cp_len = hdr48->data[0];
|
|
if (payload_len + 1 < cp_len) {
|
|
LOGP(DNAT, LOGL_ERROR, "SMS RPDU can not fit in: %d %d\n", cp_len, payload_len);
|
|
return NULL;
|
|
}
|
|
|
|
if (hdr48->data[1] != GSM411_MT_RP_DATA_MO)
|
|
return NULL;
|
|
|
|
if (cp_len < 5) {
|
|
LOGP(DNAT, LOGL_ERROR, "RD-DATA can not fit in the CP len: %d\n", cp_len);
|
|
return NULL;
|
|
}
|
|
|
|
/* RP */
|
|
ref = hdr48->data[2];
|
|
orig_addr_len = hdr48->data[3];
|
|
orig_addr_ptr = &hdr48->data[4];
|
|
|
|
/* the +1 is for checking if the following element has some space */
|
|
if (cp_len < 3 + orig_addr_len + 1) {
|
|
LOGP(DNAT, LOGL_ERROR, "RP-Originator addr does not fit: %d\n", orig_addr_len);
|
|
return NULL;
|
|
}
|
|
|
|
dest_addr_len = hdr48->data[3 + orig_addr_len + 1];
|
|
dest_addr_ptr = &hdr48->data[3 + orig_addr_len + 2];
|
|
|
|
if (cp_len < 3 + orig_addr_len + 1 + dest_addr_len + 1) {
|
|
LOGP(DNAT, LOGL_ERROR, "RP-Destination addr does not fit: %d\n", dest_addr_len);
|
|
return NULL;
|
|
}
|
|
gsm48_decode_bcd_number(smsc_addr, ARRAY_SIZE(smsc_addr), dest_addr_ptr - 1, 1);
|
|
|
|
data_len = hdr48->data[3 + orig_addr_len + 1 + dest_addr_len + 1];
|
|
data_ptr = &hdr48->data[3 + orig_addr_len + 1 + dest_addr_len + 2];
|
|
|
|
if (cp_len < 3 + orig_addr_len + 1 + dest_addr_len + 1 + data_len) {
|
|
LOGP(DNAT, LOGL_ERROR, "RP-Data does not fit: %d\n", data_len);
|
|
return NULL;
|
|
}
|
|
|
|
if (data_len < 3) {
|
|
LOGP(DNAT, LOGL_ERROR, "SMS-SUBMIT is too short.\n");
|
|
return NULL;
|
|
}
|
|
|
|
/* TP-PDU starts here */
|
|
if ((data_ptr[0] & 0x03) != GSM340_SMS_SUBMIT_MS2SC)
|
|
return NULL;
|
|
|
|
/*
|
|
* look into the phone number. The length is in semi-octets, we will
|
|
* need to add the byte for the number type as well.
|
|
*/
|
|
orig_dest_len = data_ptr[2];
|
|
dest_len = ((orig_dest_len + 1) / 2) + 1;
|
|
if (data_len < dest_len + 3 || dest_len < 2) {
|
|
LOGP(DNAT, LOGL_ERROR, "SMS-SUBMIT can not have TP-DestAddr.\n");
|
|
return NULL;
|
|
}
|
|
|
|
if ((data_ptr[3] & 0x80) == 0) {
|
|
LOGP(DNAT, LOGL_ERROR, "TP-DestAddr has extension. Not handled.\n");
|
|
return NULL;
|
|
}
|
|
|
|
if ((data_ptr[3] & 0x0F) == 0) {
|
|
LOGP(DNAT, LOGL_ERROR, "TP-DestAddr is of unknown type.\n");
|
|
return NULL;
|
|
}
|
|
|
|
/**
|
|
* Besides of what I think I read in GSM 03.40 and 04.11 the TP-DA
|
|
* contains the semi-octets as length (strlen), change it to the
|
|
* the number of bytes, but then change it back.
|
|
*/
|
|
data_ptr[2] = dest_len;
|
|
gsm48_decode_bcd_number(_dest_nr + 2, ARRAY_SIZE(_dest_nr) - 2,
|
|
&data_ptr[2], 1);
|
|
data_ptr[2] = orig_dest_len;
|
|
if ((data_ptr[3] & 0x70) == 0x10) {
|
|
_dest_nr[0] = _dest_nr[1] = '0';
|
|
dest_nr = &_dest_nr[0];
|
|
} else {
|
|
dest_nr = &_dest_nr[2];
|
|
}
|
|
|
|
/**
|
|
* Call functions to rewrite the data
|
|
*/
|
|
tpdu_hdr = sms_new_tpdu_hdr(nat, imsi, dest_nr, data_ptr[0]);
|
|
new_number = find_new_smsc(nat, msg, imsi, smsc_addr, dest_nr);
|
|
new_dest_nr = sms_new_dest_nr(nat, msg, imsi, dest_nr);
|
|
|
|
if (tpdu_hdr == data_ptr[0] && !new_number && !new_dest_nr)
|
|
return NULL;
|
|
|
|
out = sms_create_new(GSM411_MT_RP_DATA_MO, ref, hdr48,
|
|
orig_addr_ptr, orig_addr_len,
|
|
new_number ? new_number : smsc_addr,
|
|
data_ptr, data_len, tpdu_hdr,
|
|
dest_len, new_dest_nr);
|
|
talloc_free(new_number);
|
|
talloc_free(new_dest_nr);
|
|
return out;
|
|
}
|
|
|
|
struct msgb *bsc_nat_rewrite_msg(struct bsc_nat *nat, struct msgb *msg, struct bsc_nat_parsed *parsed, const char *imsi)
|
|
{
|
|
struct gsm48_hdr *hdr48;
|
|
uint32_t len;
|
|
uint8_t msg_type, proto;
|
|
struct msgb *new_msg = NULL, *sccp;
|
|
uint8_t link_id;
|
|
|
|
if (!imsi || strlen(imsi) < 5)
|
|
return msg;
|
|
|
|
/* only care about DTAP messages */
|
|
if (parsed->bssap != BSSAP_MSG_DTAP)
|
|
return msg;
|
|
if (!parsed->dest_local_ref)
|
|
return msg;
|
|
|
|
hdr48 = bsc_unpack_dtap(parsed, msg, &len);
|
|
if (!hdr48)
|
|
return msg;
|
|
|
|
link_id = msg->l3h[1];
|
|
proto = hdr48->proto_discr & 0x0f;
|
|
msg_type = hdr48->msg_type & 0xbf;
|
|
|
|
if (proto == GSM48_PDISC_CC && msg_type == GSM48_MT_CC_SETUP)
|
|
new_msg = rewrite_setup(nat, msg, parsed, imsi, hdr48, len);
|
|
else if (proto == GSM48_PDISC_SMS && msg_type == GSM411_MT_CP_DATA)
|
|
new_msg = rewrite_sms(nat, msg, parsed, imsi, hdr48, len);
|
|
|
|
if (!new_msg)
|
|
return msg;
|
|
|
|
/* wrap with DTAP, SCCP, then IPA. TODO: Stop copying */
|
|
gsm0808_prepend_dtap_header(new_msg, link_id);
|
|
sccp = sccp_create_dt1(parsed->dest_local_ref, new_msg->data, new_msg->len);
|
|
talloc_free(new_msg);
|
|
|
|
if (!sccp) {
|
|
LOGP(DNAT, LOGL_ERROR, "Failed to allocate.\n");
|
|
return msg;
|
|
}
|
|
|
|
ipaccess_prepend_header(sccp, IPAC_PROTO_SCCP);
|
|
|
|
/* the parsed hangs off from msg but it needs to survive */
|
|
talloc_steal(sccp, parsed);
|
|
msgb_free(msg);
|
|
return sccp;
|
|
}
|
|
|
|
static void num_rewr_free_data(struct bsc_nat_num_rewr_entry *entry)
|
|
{
|
|
regfree(&entry->msisdn_reg);
|
|
regfree(&entry->num_reg);
|
|
talloc_free(entry->replace);
|
|
}
|
|
|
|
void bsc_nat_num_rewr_entry_adapt(void *ctx, struct llist_head *head,
|
|
const struct osmo_config_list *list)
|
|
{
|
|
struct bsc_nat_num_rewr_entry *entry, *tmp;
|
|
struct osmo_config_entry *cfg_entry;
|
|
|
|
/* free the old data */
|
|
llist_for_each_entry_safe(entry, tmp, head, list) {
|
|
num_rewr_free_data(entry);
|
|
llist_del(&entry->list);
|
|
talloc_free(entry);
|
|
}
|
|
|
|
|
|
if (!list)
|
|
return;
|
|
|
|
llist_for_each_entry(cfg_entry, &list->entry, list) {
|
|
char *regexp;
|
|
if (cfg_entry->text[0] == '+') {
|
|
LOGP(DNAT, LOGL_ERROR,
|
|
"Plus is not allowed in the number\n");
|
|
continue;
|
|
}
|
|
|
|
entry = talloc_zero(ctx, struct bsc_nat_num_rewr_entry);
|
|
if (!entry) {
|
|
LOGP(DNAT, LOGL_ERROR,
|
|
"Allication of the num_rewr entry failed.\n");
|
|
continue;
|
|
}
|
|
|
|
entry->replace = talloc_strdup(entry, cfg_entry->text);
|
|
if (!entry->replace) {
|
|
LOGP(DNAT, LOGL_ERROR,
|
|
"Failed to copy the replacement text.\n");
|
|
talloc_free(entry);
|
|
continue;
|
|
}
|
|
|
|
/* we will now build a regexp string */
|
|
if (cfg_entry->mcc[0] == '^') {
|
|
regexp = talloc_strdup(entry, cfg_entry->mcc);
|
|
} else {
|
|
regexp = talloc_asprintf(entry, "^%s%s",
|
|
cfg_entry->mcc[0] == '*' ?
|
|
"[0-9][0-9][0-9]" : cfg_entry->mcc,
|
|
cfg_entry->mnc[0] == '*' ?
|
|
"[0-9][0-9]" : cfg_entry->mnc);
|
|
}
|
|
|
|
if (!regexp) {
|
|
LOGP(DNAT, LOGL_ERROR, "Failed to create a regexp string.\n");
|
|
talloc_free(entry);
|
|
continue;
|
|
}
|
|
|
|
if (regcomp(&entry->msisdn_reg, regexp, 0) != 0) {
|
|
LOGP(DNAT, LOGL_ERROR,
|
|
"Failed to compile regexp '%s'\n", regexp);
|
|
talloc_free(regexp);
|
|
talloc_free(entry);
|
|
continue;
|
|
}
|
|
|
|
talloc_free(regexp);
|
|
if (regcomp(&entry->num_reg, cfg_entry->option, REG_EXTENDED) != 0) {
|
|
LOGP(DNAT, LOGL_ERROR,
|
|
"Failed to compile regexp '%s'\n", cfg_entry->option);
|
|
regfree(&entry->msisdn_reg);
|
|
talloc_free(entry);
|
|
continue;
|
|
}
|
|
|
|
/* we have copied the number */
|
|
llist_add_tail(&entry->list, head);
|
|
}
|
|
}
|