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nat: Move the IMSI/TMSI filtering to a new and dedicated file
Move all routines related to filtering to a separate file.
This commit is contained in:
Holger Hans Peter Freyther
@@ -6,7 +6,8 @@ bin_PROGRAMS = osmo-bsc_nat
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osmo_bsc_nat_SOURCES = bsc_filter.c bsc_mgcp_utils.c bsc_nat.c bsc_nat_utils.c \
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osmo_bsc_nat_SOURCES = bsc_filter.c bsc_mgcp_utils.c bsc_nat.c bsc_nat_utils.c \
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bsc_nat_vty.c bsc_sccp.c bsc_ussd.c bsc_nat_ctrl.c bsc_nat_rewrite.c
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bsc_nat_vty.c bsc_sccp.c bsc_ussd.c bsc_nat_ctrl.c \
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bsc_nat_rewrite.c bsc_nat_filter.c
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osmo_bsc_nat_LDADD = $(top_builddir)/src/libcommon/libcommon.a \
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osmo_bsc_nat_LDADD = $(top_builddir)/src/libcommon/libcommon.a \
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$(top_builddir)/src/libmgcp/libmgcp.a \
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$(top_builddir)/src/libmgcp/libmgcp.a \
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$(top_builddir)/src/libbsc/libbsc.a \
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$(top_builddir)/src/libbsc/libbsc.a \
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320
openbsc/src/osmo-bsc_nat/bsc_nat_filter.c
Normal file
320
openbsc/src/osmo-bsc_nat/bsc_nat_filter.c
Normal file
@@ -0,0 +1,320 @@
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/*
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* Access filtering
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*/
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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 <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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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,
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int *con_type, char **imsi)
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{
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static const uint32_t classmark_offset =
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offsetof(struct gsm48_service_request, classmark);
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char mi_string[GSM48_MI_SIZE];
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uint8_t mi_type;
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int rc;
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struct gsm48_service_request *req;
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/* unfortunately in Phase1 the classmark2 length is variable */
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if (length < sizeof(*req)) {
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LOGP(DNAT, LOGL_ERROR,
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"CM Serv Req does not fit. Length is %d\n", length);
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return -1;
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}
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req = (struct gsm48_service_request *) data;
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if (req->cm_service_type == 0x8)
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*con_type = NAT_CON_TYPE_SSA;
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rc = gsm48_extract_mi((uint8_t *) &req->classmark,
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length - classmark_offset, mi_string, &mi_type);
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if (rc < 0) {
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LOGP(DNAT, LOGL_ERROR, "Failed to parse the classmark2/mi. error: %d\n", rc);
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return -1;
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}
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/* we have to let the TMSI or such pass */
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if (mi_type != GSM_MI_TYPE_IMSI)
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return 0;
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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_pag_resp(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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struct gsm48_pag_resp *resp;
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char mi_string[GSM48_MI_SIZE];
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uint8_t mi_type;
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if (length < sizeof(*resp)) {
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LOGP(DNAT, LOGL_ERROR, "PAG RESP does not fit. Length was %d.\n", length);
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return -1;
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}
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resp = (struct gsm48_pag_resp *) data;
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if (gsm48_paging_extract_mi(resp, length, mi_string, &mi_type) < 0) {
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LOGP(DNAT, LOGL_ERROR, "Failed to extract the MI.\n");
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return -1;
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}
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/* we need to let it pass for now */
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if (mi_type != GSM_MI_TYPE_IMSI)
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return 0;
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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 _dt_check_id_resp(struct bsc_connection *bsc,
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uint8_t *data, unsigned int length,
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struct sccp_connections *con)
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{
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char mi_string[GSM48_MI_SIZE];
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uint8_t mi_type;
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int ret;
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if (length < 2) {
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LOGP(DNAT, LOGL_ERROR, "mi does not fit.\n");
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return -1;
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}
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if (data[0] < length - 1) {
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LOGP(DNAT, LOGL_ERROR, "mi length too big.\n");
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return -2;
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}
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mi_type = data[1] & GSM_MI_TYPE_MASK;
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gsm48_mi_to_string(mi_string, sizeof(mi_string), &data[1], data[0]);
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if (mi_type != GSM_MI_TYPE_IMSI)
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return 0;
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ret = auth_imsi(bsc, mi_string);
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con->imsi_checked = 1;
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con->imsi = talloc_strdup(con, mi_string);
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return ret;
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}
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/* Filter out CR data... */
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int bsc_nat_filter_sccp_cr(struct bsc_connection *bsc, struct msgb *msg,
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struct bsc_nat_parsed *parsed, int *con_type,
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char **imsi)
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{
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struct tlv_parsed tp;
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struct gsm48_hdr *hdr48;
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int hdr48_len;
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int len;
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uint8_t msg_type, proto;
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*con_type = NAT_CON_TYPE_NONE;
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*imsi = NULL;
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if (parsed->gsm_type != BSS_MAP_MSG_COMPLETE_LAYER_3) {
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LOGP(DNAT, LOGL_ERROR,
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"Rejecting CR message due wrong GSM Type %d\n", parsed->gsm_type);
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return -1;
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}
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/* the parsed has had some basic l3 length check */
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len = msg->l3h[1];
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if (msgb_l3len(msg) - 3 < len) {
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LOGP(DNAT, LOGL_ERROR,
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"The CR Data has not enough space...\n");
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return -1;
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}
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msg->l4h = &msg->l3h[3];
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len -= 1;
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tlv_parse(&tp, gsm0808_att_tlvdef(), msg->l4h, len, 0, 0);
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if (!TLVP_PRESENT(&tp, GSM0808_IE_LAYER_3_INFORMATION)) {
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LOGP(DNAT, LOGL_ERROR, "CR Data does not contain layer3 information.\n");
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return -1;
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}
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hdr48_len = TLVP_LEN(&tp, GSM0808_IE_LAYER_3_INFORMATION);
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if (hdr48_len < sizeof(*hdr48)) {
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LOGP(DNAT, LOGL_ERROR, "GSM48 header does not fit.\n");
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return -1;
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}
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hdr48 = (struct gsm48_hdr *) TLVP_VAL(&tp, GSM0808_IE_LAYER_3_INFORMATION);
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proto = hdr48->proto_discr & 0x0f;
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msg_type = hdr48->msg_type & 0xbf;
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if (proto == GSM48_PDISC_MM &&
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msg_type == GSM48_MT_MM_LOC_UPD_REQUEST) {
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*con_type = NAT_CON_TYPE_LU;
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return _cr_check_loc_upd(bsc, &hdr48->data[0], hdr48_len - sizeof(*hdr48), imsi);
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} else if (proto == GSM48_PDISC_MM &&
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msg_type == GSM48_MT_MM_CM_SERV_REQ) {
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*con_type = NAT_CON_TYPE_CM_SERV_REQ;
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return _cr_check_cm_serv_req(bsc, &hdr48->data[0],
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hdr48_len - sizeof(*hdr48),
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con_type, imsi);
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} else if (proto == GSM48_PDISC_RR &&
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msg_type == GSM48_MT_RR_PAG_RESP) {
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*con_type = NAT_CON_TYPE_PAG_RESP;
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return _cr_check_pag_resp(bsc, &hdr48->data[0], hdr48_len - sizeof(*hdr48), imsi);
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} else {
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/* We only want to filter the above, let other things pass */
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*con_type = NAT_CON_TYPE_OTHER;
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return 0;
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}
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}
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int bsc_nat_filter_dt(struct bsc_connection *bsc, struct msgb *msg,
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struct sccp_connections *con, struct bsc_nat_parsed *parsed)
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{
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uint32_t len;
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uint8_t msg_type, proto;
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struct gsm48_hdr *hdr48;
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if (con->imsi_checked)
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return 0;
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/* only care about DTAP messages */
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if (parsed->bssap != BSSAP_MSG_DTAP)
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return 0;
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hdr48 = bsc_unpack_dtap(parsed, msg, &len);
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if (!hdr48)
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return -1;
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proto = hdr48->proto_discr & 0x0f;
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msg_type = hdr48->msg_type & 0xbf;
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if (proto == GSM48_PDISC_MM &&
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msg_type == GSM48_MT_MM_ID_RESP) {
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return _dt_check_id_resp(bsc, &hdr48->data[0], len - sizeof(*hdr48), con);
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} else {
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return 0;
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}
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}
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@@ -374,259 +374,6 @@ int bsc_nat_lst_check_allow(struct bsc_nat_acc_lst *lst, const char *mi_string)
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return 1;
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return 1;
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}
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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 */
|
|
||||||
static int auth_imsi(struct bsc_connection *bsc, const char *mi_string)
|
|
||||||
{
|
|
||||||
/*
|
|
||||||
* Now apply blacklist/whitelist of the BSC and the NAT.
|
|
||||||
* 1.) Allow directly if the IMSI is allowed at the BSC
|
|
||||||
* 2.) Reject if the IMSI is not allowed at the BSC
|
|
||||||
* 3.) Reject if the IMSI not allowed at the global level.
|
|
||||||
* 4.) Allow directly if the IMSI is allowed at the global level
|
|
||||||
*/
|
|
||||||
struct bsc_nat_acc_lst *nat_lst = NULL;
|
|
||||||
struct bsc_nat_acc_lst *bsc_lst = NULL;
|
|
||||||
|
|
||||||
bsc_lst = bsc_nat_acc_lst_find(bsc->nat, bsc->cfg->acc_lst_name);
|
|
||||||
nat_lst = bsc_nat_acc_lst_find(bsc->nat, bsc->nat->acc_lst_name);
|
|
||||||
|
|
||||||
|
|
||||||
if (bsc_lst) {
|
|
||||||
/* 1. BSC allow */
|
|
||||||
if (bsc_nat_lst_check_allow(bsc_lst, mi_string) == 0)
|
|
||||||
return 1;
|
|
||||||
|
|
||||||
/* 2. BSC deny */
|
|
||||||
if (lst_check_deny(bsc_lst, mi_string) == 0) {
|
|
||||||
LOGP(DNAT, LOGL_ERROR,
|
|
||||||
"Filtering %s by imsi_deny on bsc nr: %d.\n", mi_string, bsc->cfg->nr);
|
|
||||||
rate_ctr_inc(&bsc_lst->stats->ctr[ACC_LIST_BSC_FILTER]);
|
|
||||||
return -2;
|
|
||||||
}
|
|
||||||
|
|
||||||
}
|
|
||||||
|
|
||||||
/* 3. NAT deny */
|
|
||||||
if (nat_lst) {
|
|
||||||
if (lst_check_deny(nat_lst, mi_string) == 0) {
|
|
||||||
LOGP(DNAT, LOGL_ERROR,
|
|
||||||
"Filtering %s by nat imsi_deny on bsc nr: %d.\n", mi_string, bsc->cfg->nr);
|
|
||||||
rate_ctr_inc(&nat_lst->stats->ctr[ACC_LIST_NAT_FILTER]);
|
|
||||||
return -3;
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
return 1;
|
|
||||||
}
|
|
||||||
|
|
||||||
static int _cr_check_loc_upd(struct bsc_connection *bsc,
|
|
||||||
uint8_t *data, unsigned int length,
|
|
||||||
char **imsi)
|
|
||||||
{
|
|
||||||
uint8_t mi_type;
|
|
||||||
struct gsm48_loc_upd_req *lu;
|
|
||||||
char mi_string[GSM48_MI_SIZE];
|
|
||||||
|
|
||||||
if (length < sizeof(*lu)) {
|
|
||||||
LOGP(DNAT, LOGL_ERROR,
|
|
||||||
"LU does not fit. Length is %d \n", length);
|
|
||||||
return -1;
|
|
||||||
}
|
|
||||||
|
|
||||||
lu = (struct gsm48_loc_upd_req *) data;
|
|
||||||
mi_type = lu->mi[0] & GSM_MI_TYPE_MASK;
|
|
||||||
|
|
||||||
/*
|
|
||||||
* We can only deal with the IMSI. This will fail for a phone that
|
|
||||||
* will send the TMSI of a previous network to us.
|
|
||||||
*/
|
|
||||||
if (mi_type != GSM_MI_TYPE_IMSI)
|
|
||||||
return 0;
|
|
||||||
|
|
||||||
gsm48_mi_to_string(mi_string, sizeof(mi_string), lu->mi, lu->mi_len);
|
|
||||||
*imsi = talloc_strdup(bsc, mi_string);
|
|
||||||
return auth_imsi(bsc, mi_string);
|
|
||||||
}
|
|
||||||
|
|
||||||
static int _cr_check_cm_serv_req(struct bsc_connection *bsc,
|
|
||||||
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 gsm48_hdr *bsc_unpack_dtap(struct bsc_nat_parsed *parsed,
|
||||||
struct msgb *msg, uint32_t *len)
|
struct msgb *msg, uint32_t *len)
|
||||||
{
|
{
|
||||||
@@ -648,34 +395,6 @@ struct gsm48_hdr *bsc_unpack_dtap(struct bsc_nat_parsed *parsed,
|
|||||||
return (struct gsm48_hdr *) msg->l4h;
|
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 [] = {
|
static const char *con_types [] = {
|
||||||
[NAT_CON_TYPE_NONE] = "n/a",
|
[NAT_CON_TYPE_NONE] = "n/a",
|
||||||
[NAT_CON_TYPE_LU] = "Location Update",
|
[NAT_CON_TYPE_LU] = "Location Update",
|
||||||
|
|||||||
@@ -10,6 +10,7 @@ bsc_nat_test_SOURCES = bsc_nat_test.c \
|
|||||||
$(top_srcdir)/src/osmo-bsc_nat/bsc_filter.c \
|
$(top_srcdir)/src/osmo-bsc_nat/bsc_filter.c \
|
||||||
$(top_srcdir)/src/osmo-bsc_nat/bsc_sccp.c \
|
$(top_srcdir)/src/osmo-bsc_nat/bsc_sccp.c \
|
||||||
$(top_srcdir)/src/osmo-bsc_nat/bsc_nat_utils.c \
|
$(top_srcdir)/src/osmo-bsc_nat/bsc_nat_utils.c \
|
||||||
|
$(top_srcdir)/src/osmo-bsc_nat/bsc_nat_filter.c \
|
||||||
$(top_srcdir)/src/osmo-bsc_nat/bsc_nat_rewrite.c \
|
$(top_srcdir)/src/osmo-bsc_nat/bsc_nat_rewrite.c \
|
||||||
$(top_srcdir)/src/osmo-bsc_nat/bsc_mgcp_utils.c
|
$(top_srcdir)/src/osmo-bsc_nat/bsc_mgcp_utils.c
|
||||||
bsc_nat_test_LDADD = $(top_builddir)/src/libbsc/libbsc.a \
|
bsc_nat_test_LDADD = $(top_builddir)/src/libbsc/libbsc.a \
|
||||||
|
|||||||
Reference in New Issue
Block a user