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When sending a MSG to the MSC try to find the to be used "src" reference by comparing the reference on the BSC and the BSC connection. Only this tuple needs to be unique. Actually only when looking at the SRC REF we need to compare the BSC as the dest reference should be unique but we are just making the check a bit stronger to make it look symmetric.
560 lines
13 KiB
C
560 lines
13 KiB
C
/*
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* BSC NAT Message filtering
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*
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* (C) 2010 by Holger Hans Peter Freyther <zecke@selfish.org>
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* (C) 2010 by On-Waves
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*
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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 General Public License as published by
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* the Free Software Foundation; either version 2 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 General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License along
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* with this program; if not, write to the Free Software Foundation, Inc.,
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* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
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*
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*/
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#include <openbsc/debug.h>
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#include <openbsc/gsm_data.h>
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#include <openbsc/bsc_nat.h>
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#include <osmocore/talloc.h>
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#include <stdio.h>
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/* test messages for ipa */
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static u_int8_t ipa_id[] = {
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0x00, 0x01, 0xfe, 0x06,
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};
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/* SCCP messages are below */
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static u_int8_t gsm_reset[] = {
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0x00, 0x12, 0xfd,
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0x09, 0x00, 0x03, 0x05, 0x07, 0x02, 0x42, 0xfe,
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0x02, 0x42, 0xfe, 0x06, 0x00, 0x04, 0x30, 0x04,
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0x01, 0x20,
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};
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static const u_int8_t gsm_reset_ack[] = {
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0x00, 0x13, 0xfd,
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0x09, 0x00, 0x03, 0x07, 0x0b, 0x04, 0x43, 0x01,
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0x00, 0xfe, 0x04, 0x43, 0x5c, 0x00, 0xfe, 0x03,
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0x00, 0x01, 0x31,
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};
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static const u_int8_t gsm_paging[] = {
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0x00, 0x20, 0xfd,
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0x09, 0x00, 0x03, 0x07, 0x0b, 0x04, 0x43, 0x01,
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0x00, 0xfe, 0x04, 0x43, 0x5c, 0x00, 0xfe, 0x10,
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0x00, 0x0e, 0x52, 0x08, 0x08, 0x29, 0x47, 0x10,
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0x02, 0x01, 0x31, 0x97, 0x61, 0x1a, 0x01, 0x06,
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};
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/* BSC -> MSC connection open */
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static const u_int8_t bssmap_cr[] = {
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0x00, 0x2c, 0xfd,
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0x01, 0x01, 0x02, 0x03, 0x02, 0x02, 0x04, 0x02,
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0x42, 0xfe, 0x0f, 0x1f, 0x00, 0x1d, 0x57, 0x05,
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0x08, 0x00, 0x72, 0xf4, 0x80, 0x20, 0x12, 0xc3,
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0x50, 0x17, 0x10, 0x05, 0x24, 0x11, 0x03, 0x33,
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0x19, 0xa2, 0x08, 0x29, 0x47, 0x10, 0x02, 0x01,
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0x31, 0x97, 0x61, 0x00
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};
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/* MSC -> BSC connection confirm */
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static const u_int8_t bssmap_cc[] = {
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0x00, 0x0a, 0xfd,
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0x02, 0x01, 0x02, 0x03, 0x00, 0x00, 0x03, 0x02, 0x01, 0x00,
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};
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/* MSC -> BSC released */
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static const u_int8_t bssmap_released[] = {
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0x00, 0x0e, 0xfd,
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0x04, 0x00, 0x00, 0x03, 0x01, 0x02, 0x03, 0x00, 0x01, 0x0f,
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0x02, 0x23, 0x42, 0x00,
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};
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/* BSC -> MSC released */
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static const u_int8_t bssmap_release_complete[] = {
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0x00, 0x07, 0xfd,
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0x05, 0x01, 0x02, 0x03, 0x00, 0x00, 0x03
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};
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/* both directions IT timer */
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static const u_int8_t connnection_it[] = {
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0x00, 0x0b, 0xfd,
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0x10, 0x01, 0x02, 0x03, 0x01, 0x02, 0x03,
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0x00, 0x00, 0x00, 0x00,
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};
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/* error in both directions */
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static const u_int8_t proto_error[] = {
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0x00, 0x05, 0xfd,
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0x0f, 0x22, 0x33, 0x44, 0x00,
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};
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/* MGCP wrap... */
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static const u_int8_t mgcp_msg[] = {
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0x00, 0x03, 0xfc,
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0x20, 0x20, 0x20,
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};
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struct filter_result {
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const u_int8_t *data;
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const u_int16_t length;
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const int dir;
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const int result;
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};
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static const struct filter_result results[] = {
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{
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.data = ipa_id,
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.length = ARRAY_SIZE(ipa_id),
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.dir = DIR_MSC,
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.result = 1,
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},
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{
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.data = gsm_reset,
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.length = ARRAY_SIZE(gsm_reset),
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.dir = DIR_MSC,
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.result = 1,
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},
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{
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.data = gsm_reset_ack,
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.length = ARRAY_SIZE(gsm_reset_ack),
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.dir = DIR_BSC,
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.result = 1,
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},
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{
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.data = gsm_paging,
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.length = ARRAY_SIZE(gsm_paging),
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.dir = DIR_BSC,
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.result = 0,
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},
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{
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.data = bssmap_cr,
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.length = ARRAY_SIZE(bssmap_cr),
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.dir = DIR_MSC,
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.result = 0,
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},
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{
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.data = bssmap_cc,
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.length = ARRAY_SIZE(bssmap_cc),
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.dir = DIR_BSC,
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.result = 0,
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},
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{
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.data = bssmap_released,
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.length = ARRAY_SIZE(bssmap_released),
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.dir = DIR_MSC,
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.result = 0,
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},
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{
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.data = bssmap_release_complete,
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.length = ARRAY_SIZE(bssmap_release_complete),
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.dir = DIR_BSC,
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.result = 0,
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},
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{
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.data = mgcp_msg,
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.length = ARRAY_SIZE(mgcp_msg),
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.dir = DIR_MSC,
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.result = 0,
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},
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{
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.data = connnection_it,
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.length = ARRAY_SIZE(connnection_it),
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.dir = DIR_BSC,
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.result = 0,
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},
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{
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.data = connnection_it,
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.length = ARRAY_SIZE(connnection_it),
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.dir = DIR_MSC,
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.result = 0,
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},
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{
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.data = proto_error,
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.length = ARRAY_SIZE(proto_error),
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.dir = DIR_BSC,
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.result = 0,
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},
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{
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.data = proto_error,
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.length = ARRAY_SIZE(proto_error),
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.dir = DIR_MSC,
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.result = 0,
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},
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};
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static void test_filter(void)
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{
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int i;
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/* start testinh with proper messages */
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fprintf(stderr, "Testing BSS Filtering.\n");
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for (i = 0; i < ARRAY_SIZE(results); ++i) {
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int result;
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struct bsc_nat_parsed *parsed;
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struct msgb *msg = msgb_alloc(4096, "test-message");
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fprintf(stderr, "Going to test item: %d\n", i);
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memcpy(msg->data, results[i].data, results[i].length);
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msg->l2h = msgb_put(msg, results[i].length);
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parsed = bsc_nat_parse(msg);
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if (!parsed) {
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fprintf(stderr, "FAIL: Failed to parse the message\n");
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continue;
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}
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result = bsc_nat_filter_ipa(results[i].dir, msg, parsed);
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if (result != results[i].result) {
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fprintf(stderr, "FAIL: Not the expected result got: %d wanted: %d\n",
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result, results[i].result);
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}
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msgb_free(msg);
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}
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}
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#include "bsc_data.c"
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static void copy_to_msg(struct msgb *msg, const u_int8_t *data, unsigned int length)
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{
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msgb_reset(msg);
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msg->l2h = msgb_put(msg, length);
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memcpy(msg->l2h, data, msgb_l2len(msg));
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}
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#define VERIFY(con_found, con, msg, ver, str) \
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if (!con_found || con_found->bsc != con) { \
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fprintf(stderr, "Failed to find the con: %p\n", con_found); \
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abort(); \
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} \
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if (memcmp(msg->data, ver, sizeof(ver)) != 0) { \
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fprintf(stderr, "Failed to patch the %s msg.\n", str); \
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abort(); \
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}
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/* test conn tracking once */
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static void test_contrack()
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{
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int rc;
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struct bsc_nat *nat;
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struct bsc_connection *con;
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struct sccp_connections *con_found;
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struct bsc_nat_parsed *parsed;
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struct msgb *msg;
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fprintf(stderr, "Testing connection tracking.\n");
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nat = bsc_nat_alloc();
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con = bsc_connection_alloc(nat);
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con->cfg = bsc_config_alloc(nat, "foo", 23);
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msg = msgb_alloc(4096, "test");
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/* 1.) create a connection */
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copy_to_msg(msg, bsc_cr, sizeof(bsc_cr));
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parsed = bsc_nat_parse(msg);
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con_found = patch_sccp_src_ref_to_msc(msg, parsed, con);
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if (con_found != NULL) {
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fprintf(stderr, "Con should not exist %p\n", con_found);
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abort();
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}
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rc = create_sccp_src_ref(con, msg, parsed);
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if (rc != 0) {
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fprintf(stderr, "Failed to create a ref\n");
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abort();
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}
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con_found = patch_sccp_src_ref_to_msc(msg, parsed, con);
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if (!con_found || con_found->bsc != con) {
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fprintf(stderr, "Failed to find the con: %p\n", con_found);
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abort();
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}
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if (memcmp(msg->data, bsc_cr_patched, sizeof(bsc_cr_patched)) != 0) {
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fprintf(stderr, "Failed to patch the BSC CR msg.\n");
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abort();
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}
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talloc_free(parsed);
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/* 2.) get the cc */
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copy_to_msg(msg, msc_cc, sizeof(msc_cc));
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parsed = bsc_nat_parse(msg);
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con_found = patch_sccp_src_ref_to_bsc(msg, parsed, nat);
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VERIFY(con_found, con, msg, msc_cc_patched, "MSC CC");
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if (update_sccp_src_ref(con_found, parsed) != 0) {
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fprintf(stderr, "Failed to update the SCCP con.\n");
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abort();
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}
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/* 3.) send some data */
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copy_to_msg(msg, bsc_dtap, sizeof(bsc_dtap));
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parsed = bsc_nat_parse(msg);
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con_found = patch_sccp_src_ref_to_msc(msg, parsed, con);
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VERIFY(con_found, con, msg, bsc_dtap_patched, "BSC DTAP");
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/* 4.) receive some data */
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copy_to_msg(msg, msc_dtap, sizeof(msc_dtap));
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parsed = bsc_nat_parse(msg);
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con_found = patch_sccp_src_ref_to_bsc(msg, parsed, nat);
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VERIFY(con_found, con, msg, msc_dtap_patched, "MSC DTAP");
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/* 5.) close the connection */
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copy_to_msg(msg, msc_rlsd, sizeof(msc_rlsd));
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parsed = bsc_nat_parse(msg);
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con_found = patch_sccp_src_ref_to_bsc(msg, parsed, nat);
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VERIFY(con_found, con, msg, msc_rlsd_patched, "MSC RLSD");
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/* 6.) confirm the connection close */
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copy_to_msg(msg, bsc_rlc, sizeof(bsc_rlc));
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parsed = bsc_nat_parse(msg);
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con_found = patch_sccp_src_ref_to_msc(msg, parsed, con);
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if (!con_found || con_found->bsc != con) {
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fprintf(stderr, "Failed to find the con: %p\n", con_found);
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abort();
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}
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if (memcmp(msg->data, bsc_rlc_patched, sizeof(bsc_rlc_patched)) != 0) {
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fprintf(stderr, "Failed to patch the BSC CR msg.\n");
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abort();
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}
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remove_sccp_src_ref(con, msg, parsed);
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talloc_free(parsed);
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copy_to_msg(msg, bsc_rlc, sizeof(bsc_rlc));
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parsed = bsc_nat_parse(msg);
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con_found = patch_sccp_src_ref_to_msc(msg, parsed, con);
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/* verify that it is gone */
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if (con_found != NULL) {
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fprintf(stderr, "Con should be gone. %p\n", con_found);
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abort();
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}
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talloc_free(parsed);
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talloc_free(nat);
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msgb_free(msg);
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}
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static void test_paging(void)
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{
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int lac;
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struct bsc_nat *nat;
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struct bsc_connection *con;
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struct bsc_nat_parsed *parsed;
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struct bsc_config cfg;
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struct msgb *msg;
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fprintf(stderr, "Testing paging by lac.\n");
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nat = bsc_nat_alloc();
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con = bsc_connection_alloc(nat);
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con->cfg = &cfg;
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cfg.lac = 23;
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con->authenticated = 1;
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llist_add(&con->list_entry, &nat->bsc_connections);
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msg = msgb_alloc(4096, "test");
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/* Test completely bad input */
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copy_to_msg(msg, paging_by_lac_cmd, sizeof(paging_by_lac_cmd));
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if (bsc_nat_find_bsc(nat, msg, &lac) != 0) {
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fprintf(stderr, "Should have not found anything.\n");
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abort();
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}
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/* Test it by not finding it */
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copy_to_msg(msg, paging_by_lac_cmd, sizeof(paging_by_lac_cmd));
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parsed = bsc_nat_parse(msg);
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if (bsc_nat_find_bsc(nat, msg, &lac) != 0) {
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fprintf(stderr, "Should have not found aynthing.\n");
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abort();
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}
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talloc_free(parsed);
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/* Test by finding it */
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cfg.lac = 8213;
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copy_to_msg(msg, paging_by_lac_cmd, sizeof(paging_by_lac_cmd));
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parsed = bsc_nat_parse(msg);
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if (bsc_nat_find_bsc(nat, msg, &lac) != con) {
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fprintf(stderr, "Should have found it.\n");
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abort();
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}
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talloc_free(parsed);
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}
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static void test_mgcp_ass_tracking(void)
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{
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struct sccp_connections con;
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struct bsc_nat_parsed *parsed;
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struct msgb *msg;
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fprintf(stderr, "Testing MGCP.\n");
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memset(&con, 0, sizeof(con));
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msg = msgb_alloc(4096, "foo");
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copy_to_msg(msg, ass_cmd, sizeof(ass_cmd));
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parsed = bsc_nat_parse(msg);
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if (bsc_mgcp_assign(&con, msg) != 0) {
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fprintf(stderr, "Failed to handle assignment.\n");
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abort();
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}
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if (con.msc_timeslot != 21) {
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fprintf(stderr, "Timeslot should be 21.\n");
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abort();
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}
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if (con.bsc_timeslot != 21) {
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fprintf(stderr, "Assigned timeslot should have been 21.\n");
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abort();
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}
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talloc_free(parsed);
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bsc_mgcp_clear(&con);
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if (con.bsc_timeslot != -1 || con.msc_timeslot != -1) {
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fprintf(stderr, "Clearing should remove the mapping.\n");
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abort();
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}
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}
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/* test the code to find a given connection */
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static void test_mgcp_find(void)
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{
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struct bsc_nat *nat;
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struct bsc_connection *con;
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struct sccp_connections *sccp_con;
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fprintf(stderr, "Testing finding of a BSC Connection\n");
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nat = bsc_nat_alloc();
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con = bsc_connection_alloc(nat);
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llist_add(&con->list_entry, &nat->bsc_connections);
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sccp_con = talloc_zero(con, struct sccp_connections);
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sccp_con->msc_timeslot = 12;
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sccp_con->bsc_timeslot = 12;
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sccp_con->bsc = con;
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llist_add(&sccp_con->list_entry, &nat->sccp_connections);
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if (bsc_mgcp_find_con(nat, 11) != NULL) {
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fprintf(stderr, "Found the wrong connection.\n");
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abort();
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}
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if (bsc_mgcp_find_con(nat, 12) != sccp_con) {
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fprintf(stderr, "Didn't find the connection\n");
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abort();
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}
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sccp_con->msc_timeslot = 0;
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sccp_con->bsc_timeslot = 0;
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if (bsc_mgcp_find_con(nat, 1) != sccp_con) {
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fprintf(stderr, "Didn't find the connection\n");
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abort();
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}
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/* free everything */
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talloc_free(nat);
|
|
}
|
|
|
|
static void test_mgcp_rewrite(void)
|
|
{
|
|
int i;
|
|
struct msgb *output;
|
|
fprintf(stderr, "Test rewriting MGCP messages.\n");
|
|
|
|
for (i = 0; i < ARRAY_SIZE(mgcp_messages); ++i) {
|
|
const char *orig = mgcp_messages[i].orig;
|
|
const char *patc = mgcp_messages[i].patch;
|
|
const char *ip = mgcp_messages[i].ip;
|
|
const int port = mgcp_messages[i].port;
|
|
|
|
char *input = strdup(orig);
|
|
|
|
output = bsc_mgcp_rewrite(input, strlen(input), ip, port);
|
|
if (msgb_l2len(output) != strlen(patc)) {
|
|
fprintf(stderr, "Wrong sizes for test: %d %d != %d != %d\n", i, msgb_l2len(output), strlen(patc), strlen(orig));
|
|
fprintf(stderr, "String '%s' vs '%s'\n", (const char *) output->l2h, patc);
|
|
abort();
|
|
}
|
|
|
|
if (memcmp(output->l2h, patc, msgb_l2len(output)) != 0) {
|
|
fprintf(stderr, "Broken on %d msg: '%s'\n", i, (const char *) output->l2h);
|
|
abort();
|
|
}
|
|
|
|
msgb_free(output);
|
|
free(input);
|
|
}
|
|
}
|
|
|
|
static void test_mgcp_parse(void)
|
|
{
|
|
int code, ci;
|
|
char transaction[60];
|
|
|
|
fprintf(stderr, "Test MGCP response parsing.\n");
|
|
|
|
if (bsc_mgcp_parse_response(crcx_resp, &code, transaction) != 0) {
|
|
fprintf(stderr, "Failed to parse CRCX resp.\n");
|
|
abort();
|
|
}
|
|
|
|
if (code != 200) {
|
|
fprintf(stderr, "Failed to parse the CODE properly. Got: %d\n", code);
|
|
abort();
|
|
}
|
|
|
|
if (strcmp(transaction, "23265295") != 0) {
|
|
fprintf(stderr, "Failed to parse transaction id: '%s'\n", transaction);
|
|
abort();
|
|
}
|
|
|
|
ci = bsc_mgcp_extract_ci(crcx_resp);
|
|
if (ci != 1) {
|
|
fprintf(stderr, "Failed to parse the CI. Got: %d\n", ci);
|
|
abort();
|
|
}
|
|
}
|
|
|
|
int main(int argc, char **argv)
|
|
{
|
|
struct debug_target *stderr_target;
|
|
|
|
stderr_target = debug_target_create_stderr();
|
|
debug_add_target(stderr_target);
|
|
debug_set_all_filter(stderr_target, 1);
|
|
|
|
test_filter();
|
|
test_contrack();
|
|
test_paging();
|
|
test_mgcp_ass_tracking();
|
|
test_mgcp_find();
|
|
test_mgcp_rewrite();
|
|
test_mgcp_parse();
|
|
return 0;
|
|
}
|
|
|
|
void input_event()
|
|
{}
|
|
int nm_state_event()
|
|
{
|
|
return -1;
|
|
}
|
|
|
|
int gsm0408_rcvmsg(struct msgb *msg, u_int8_t link_id)
|
|
{
|
|
return -1;
|
|
}
|