| /* |
| * (C) 2010-2015 by Holger Hans Peter Freyther <zecke@selfish.org> |
| * (C) 2010-2012 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/>. |
| * |
| */ |
| |
| #include <openbsc/bsc_nat.h> |
| #include <openbsc/bsc_nat_sccp.h> |
| #include <openbsc/bsc_msg_filter.h> |
| #include <openbsc/debug.h> |
| |
| #include <osmocom/gsm/gsm0808.h> |
| |
| #include <osmocom/gsm/protocol/gsm_08_08.h> |
| #include <osmocom/gsm/protocol/gsm_04_11.h> |
| |
| #include <osmocom/sccp/sccp.h> |
| |
| /* 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 bsc_filter_reject_cause *cause) |
| { |
| struct bsc_filter_request req; |
| struct tlv_parsed tp; |
| struct gsm48_hdr *hdr48; |
| int hdr48_len; |
| int len; |
| |
| *con_type = FLT_CON_TYPE_NONE; |
| cause->cm_reject_cause = GSM48_REJECT_PLMN_NOT_ALLOWED; |
| cause->lu_reject_cause = GSM48_REJECT_PLMN_NOT_ALLOWED; |
| *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); |
| req.ctx = bsc; |
| req.black_list = &bsc->nat->imsi_black_list; |
| req.access_lists = &bsc->nat->access_lists; |
| req.local_lst_name = bsc->cfg->acc_lst_name; |
| req.global_lst_name = bsc->nat->acc_lst_name; |
| req.bsc_nr = bsc->cfg->nr; |
| return bsc_msg_filter_initial(hdr48, hdr48_len, &req, con_type, imsi, cause); |
| } |
| |
| int bsc_nat_filter_dt(struct bsc_connection *bsc, struct msgb *msg, |
| struct nat_sccp_connection *con, struct bsc_nat_parsed *parsed, |
| struct bsc_filter_reject_cause *cause) |
| { |
| uint32_t len; |
| struct gsm48_hdr *hdr48; |
| struct bsc_filter_request req; |
| |
| cause->cm_reject_cause = GSM48_REJECT_PLMN_NOT_ALLOWED; |
| cause->lu_reject_cause = GSM48_REJECT_PLMN_NOT_ALLOWED; |
| |
| if (con->filter_state.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; |
| |
| req.ctx = con; |
| req.black_list = &bsc->nat->imsi_black_list; |
| req.access_lists = &bsc->nat->access_lists; |
| req.local_lst_name = bsc->cfg->acc_lst_name; |
| req.global_lst_name = bsc->nat->acc_lst_name; |
| req.bsc_nr = bsc->cfg->nr; |
| return bsc_msg_filter_data(hdr48, len, &req, &con->filter_state, cause); |
| } |