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-rw-r--r--src/osmo-bsc_nat/bsc_mgcp_utils.c1151
1 files changed, 0 insertions, 1151 deletions
diff --git a/src/osmo-bsc_nat/bsc_mgcp_utils.c b/src/osmo-bsc_nat/bsc_mgcp_utils.c
deleted file mode 100644
index 49050fc89..000000000
--- a/src/osmo-bsc_nat/bsc_mgcp_utils.c
+++ /dev/null
@@ -1,1151 +0,0 @@
-/**
- * This file contains helper routines for MGCP Gateway handling.
- *
- * The first thing to remember is that each BSC has its own namespace/range
- * of endpoints. Whenever a BSSMAP ASSIGNMENT REQUEST is received this code
- * will be called to select an endpoint on the BSC. The mapping from original
- * multiplex/timeslot to BSC multiplex'/timeslot' will be stored.
- *
- * The second part is to take messages on the public MGCP GW interface
- * and forward them to the right BSC. This requires the MSC to first
- * assign the timeslot. This assumption has been true so far. We are using
- * the policy_cb of the MGCP protocol code to decide if the request should
- * be immediately answered or delayed. An extension "Z: noanswer" is used
- * to request the BSC to not respond. This is saving some bytes of bandwidth
- * and as we are using TCP to forward the message we know it will arrive.
- * The mgcp_do_read method reads these messages and hands them to the protocol
- * parsing code which will call the mentioned policy_cb. The bsc_mgcp_forward
- * method is used on the way back from the BSC to the network.
- *
- * The third part is to patch messages forwarded to the BSC. This includes
- * the endpoint number, the ports to be used inside the SDP file and maybe
- * some other bits.
- *
- */
-/*
- * (C) 2010-2012 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_callstats.h>
-#include <openbsc/bsc_nat_sccp.h>
-#include <openbsc/gsm_data.h>
-#include <openbsc/debug.h>
-#include <openbsc/ipaccess.h>
-#include <osmocom/legacy_mgcp/mgcp.h>
-#include <osmocom/legacy_mgcp/mgcp_internal.h>
-#include <openbsc/osmux.h>
-
-#include <osmocom/ctrl/control_cmd.h>
-
-#include <osmocom/sccp/sccp.h>
-
-#include <osmocom/core/talloc.h>
-#include <osmocom/gsm/gsm0808.h>
-#include <osmocom/gsm/protocol/gsm_08_08.h>
-
-#include <netinet/in.h>
-#include <arpa/inet.h>
-
-#include <errno.h>
-#include <unistd.h>
-
-static void send_direct(struct bsc_nat *nat, struct msgb *output)
-{
- if (osmo_wqueue_enqueue(&nat->mgcp_cfg->gw_fd, output) != 0) {
- LOGP(DMGCP, LOGL_ERROR, "Failed to queue MGCP msg.\n");
- msgb_free(output);
- }
-}
-
-static void mgcp_queue_for_call_agent(struct bsc_nat *nat, struct msgb *output)
-{
- if (nat->mgcp_ipa)
- bsc_nat_send_mgcp_to_msc(nat, output);
- else
- send_direct(nat, output);
-}
-
-int bsc_mgcp_nr_multiplexes(int max_endpoints)
-{
- int div = max_endpoints / 32;
-
- if ((max_endpoints % 32) != 0)
- div += 1;
-
- return div;
-}
-
-static int bsc_init_endps_if_needed(struct bsc_connection *con)
-{
- int multiplexes;
-
- /* we have done that */
- if (con->_endpoint_status)
- return 0;
-
- /* we have no config... */
- if (!con->cfg)
- return -1;
-
- multiplexes = bsc_mgcp_nr_multiplexes(con->cfg->max_endpoints);
- con->number_multiplexes = multiplexes;
- con->max_endpoints = con->cfg->max_endpoints;
- con->_endpoint_status = talloc_zero_array(con, char, 32 * multiplexes + 1);
- return con->_endpoint_status == NULL;
-}
-
-static int bsc_assign_endpoint(struct bsc_connection *bsc, struct nat_sccp_connection *con)
-{
- int multiplex;
- int timeslot;
- const int number_endpoints = bsc->max_endpoints;
- int i;
-
- mgcp_endpoint_to_timeslot(bsc->last_endpoint, &multiplex, &timeslot);
- timeslot += 1;
-
- for (i = 0; i < number_endpoints; ++i) {
- int endpoint;
-
- /* Wrap around timeslots */
- if (timeslot == 0)
- timeslot = 1;
-
- if (timeslot == 0x1f) {
- timeslot = 1;
- multiplex += 1;
- }
-
- /* Wrap around the multiplex */
- if (multiplex >= bsc->number_multiplexes)
- multiplex = 0;
-
- endpoint = mgcp_timeslot_to_endpoint(multiplex, timeslot);
-
- /* Now check if we are allowed to assign this one */
- if (endpoint >= bsc->max_endpoints) {
- multiplex = 0;
- timeslot = 1;
- endpoint = mgcp_timeslot_to_endpoint(multiplex, timeslot);
- }
-
-
- if (bsc->_endpoint_status[endpoint] == 0) {
- bsc->_endpoint_status[endpoint] = 1;
- con->bsc_endp = endpoint;
- bsc->last_endpoint = endpoint;
- return 0;
- }
-
- timeslot += 1;
- }
-
- return -1;
-}
-
-static uint16_t create_cic(int endpoint)
-{
- int timeslot, multiplex;
-
- mgcp_endpoint_to_timeslot(endpoint, &multiplex, &timeslot);
- return (multiplex << 5) | (timeslot & 0x1f);
-}
-
-int bsc_mgcp_assign_patch(struct nat_sccp_connection *con, struct msgb *msg)
-{
- struct nat_sccp_connection *mcon;
- struct tlv_parsed tp;
- uint16_t cic;
- uint8_t timeslot;
- uint8_t multiplex;
- unsigned int endp;
-
- if (!msg->l3h) {
- LOGP(DNAT, LOGL_ERROR, "Assignment message should have l3h pointer.\n");
- return -1;
- }
-
- if (msgb_l3len(msg) < 3) {
- LOGP(DNAT, LOGL_ERROR, "Assignment message has not enough space for GSM0808.\n");
- return -1;
- }
-
- tlv_parse(&tp, gsm0808_att_tlvdef(), msg->l3h + 3, msgb_l3len(msg) - 3, 0, 0);
- if (!TLVP_PRESENT(&tp, GSM0808_IE_CIRCUIT_IDENTITY_CODE)) {
- LOGP(DNAT, LOGL_ERROR, "Circuit identity code not found in assignment message.\n");
- return -1;
- }
-
- cic = ntohs(tlvp_val16_unal(&tp, GSM0808_IE_CIRCUIT_IDENTITY_CODE));
- timeslot = cic & 0x1f;
- multiplex = (cic & ~0x1f) >> 5;
-
-
- endp = mgcp_timeslot_to_endpoint(multiplex, timeslot);
-
- if (endp >= con->bsc->nat->mgcp_cfg->trunk.number_endpoints) {
- LOGP(DNAT, LOGL_ERROR,
- "MSC attempted to assign bad endpoint 0x%x\n",
- endp);
- return -1;
- }
-
- /* find stale connections using that endpoint */
- llist_for_each_entry(mcon, &con->bsc->nat->sccp_connections, list_entry) {
- if (mcon->msc_endp == endp) {
- LOGP(DNAT, LOGL_ERROR,
- "Endpoint %d was assigned to 0x%x and now 0x%x\n",
- endp,
- sccp_src_ref_to_int(&mcon->patched_ref),
- sccp_src_ref_to_int(&con->patched_ref));
- bsc_mgcp_dlcx(mcon);
- }
- }
-
- con->msc_endp = endp;
- if (bsc_init_endps_if_needed(con->bsc) != 0)
- return -1;
- if (bsc_assign_endpoint(con->bsc, con) != 0)
- return -1;
-
- /*
- * now patch the message for the new CIC...
- * still assumed to be one multiplex only
- */
- cic = htons(create_cic(con->bsc_endp));
- memcpy((uint8_t *) TLVP_VAL(&tp, GSM0808_IE_CIRCUIT_IDENTITY_CODE),
- &cic, sizeof(cic));
-
- return 0;
-}
-
-static void bsc_mgcp_free_endpoint(struct bsc_nat *nat, int i)
-{
- if (nat->bsc_endpoints[i].transaction_id) {
- talloc_free(nat->bsc_endpoints[i].transaction_id);
- nat->bsc_endpoints[i].transaction_id = NULL;
- }
-
- nat->bsc_endpoints[i].transaction_state = 0;
- nat->bsc_endpoints[i].bsc = NULL;
-}
-
-void bsc_mgcp_free_endpoints(struct bsc_nat *nat)
-{
- int i;
-
- for (i = 1; i < nat->mgcp_cfg->trunk.number_endpoints; ++i){
- bsc_mgcp_free_endpoint(nat, i);
- mgcp_release_endp(&nat->mgcp_cfg->trunk.endpoints[i]);
- }
-}
-
-/* send a MDCX where we do not want a response */
-static void bsc_mgcp_send_mdcx(struct bsc_connection *bsc, int port, struct mgcp_endpoint *endp)
-{
- char buf[2096];
- int len;
-
- len = snprintf(buf, sizeof(buf),
- "MDCX 23 %x@mgw MGCP 1.0\r\n"
- "Z: noanswer\r\n"
- "\r\n"
- "c=IN IP4 %s\r\n"
- "m=audio %d RTP/AVP 255\r\n",
- port, mgcp_bts_src_addr(endp),
- endp->bts_end.local_port);
- if (len < 0) {
- LOGP(DMGCP, LOGL_ERROR, "snprintf for MDCX failed.\n");
- return;
- }
-
- bsc_write_mgcp(bsc, (uint8_t *) buf, len);
-}
-
-static void bsc_mgcp_send_dlcx(struct bsc_connection *bsc, int endpoint, int trans)
-{
- char buf[2096];
- int len;
-
- /*
- * The following is a bit of a spec violation. According to the
- * MGCP grammar the transaction id is are upto 9 digits but we
- * prefix it with an alpha numeric value so we can easily recognize
- * it as a response.
- */
- len = snprintf(buf, sizeof(buf),
- "DLCX nat-%u %x@mgw MGCP 1.0\r\n",
- trans, endpoint);
- if (len < 0) {
- LOGP(DMGCP, LOGL_ERROR, "snprintf for DLCX failed.\n");
- return;
- }
-
- bsc_write_mgcp(bsc, (uint8_t *) buf, len);
-}
-
-void bsc_mgcp_init(struct nat_sccp_connection *con)
-{
- con->msc_endp = -1;
- con->bsc_endp = -1;
-}
-
-/**
- * This code will remember the network side of the audio statistics and
- * once the internal DLCX response arrives this can be combined with the
- * the BSC side and forwarded as a trap.
- */
-static void remember_pending_dlcx(struct nat_sccp_connection *con, uint32_t transaction)
-{
- struct bsc_nat_call_stats *stats;
- struct bsc_connection *bsc = con->bsc;
- struct mgcp_endpoint *endp;
-
- stats = talloc_zero(bsc, struct bsc_nat_call_stats);
- if (!stats) {
- LOGP(DNAT, LOGL_NOTICE,
- "Failed to allocate statistics for endpoint 0x%x\n",
- con->msc_endp);
- return;
- }
-
- /* take the endpoint here */
- endp = &bsc->nat->mgcp_cfg->trunk.endpoints[con->msc_endp];
-
- stats->remote_ref = con->remote_ref;
- stats->src_ref = con->patched_ref;
-
- stats->ci = endp->ci;
- stats->bts_rtp_port = endp->bts_end.rtp_port;
- stats->bts_addr = endp->bts_end.addr;
- stats->net_rtp_port = endp->net_end.rtp_port;
- stats->net_addr = endp->net_end.addr;
-
- stats->net_ps = endp->net_end.packets;
- stats->net_os = endp->net_end.octets;
- stats->bts_pr = endp->bts_end.packets;
- stats->bts_or = endp->bts_end.octets;
- mgcp_state_calc_loss(&endp->bts_state, &endp->bts_end,
- &stats->bts_expected, &stats->bts_loss);
- stats->bts_jitter = mgcp_state_calc_jitter(&endp->bts_state);
-
- stats->trans_id = transaction;
- stats->msc_endpoint = con->msc_endp;
-
- /*
- * Too many pending requests.. let's remove the first two items.
- */
- if (!llist_empty(&bsc->pending_dlcx) &&
- bsc->pending_dlcx_count >= bsc->cfg->max_endpoints * 3) {
- struct bsc_nat_call_stats *tmp;
- LOGP(DNAT, LOGL_ERROR,
- "Too many(%d) pending DLCX responses on BSC: %d\n",
- bsc->pending_dlcx_count, bsc->cfg->nr);
- bsc->pending_dlcx_count -= 1;
- tmp = (struct bsc_nat_call_stats *) bsc->pending_dlcx.next;
- llist_del(&tmp->entry);
- talloc_free(tmp);
- }
-
- bsc->pending_dlcx_count += 1;
- llist_add_tail(&stats->entry, &bsc->pending_dlcx);
-}
-
-void bsc_mgcp_dlcx(struct nat_sccp_connection *con)
-{
- /* send a DLCX down the stream */
- if (con->bsc_endp != -1 && con->bsc->_endpoint_status) {
- LOGP(DNAT, LOGL_NOTICE,
- "Endpoint 0x%x was allocated for bsc: %d. Freeing it.\n",
- con->bsc_endp, con->bsc->cfg->nr);
- if (con->bsc->_endpoint_status[con->bsc_endp] != 1)
- LOGP(DNAT, LOGL_ERROR, "Endpoint 0x%x was not in use\n", con->bsc_endp);
- remember_pending_dlcx(con, con->bsc->next_transaction);
- con->bsc->_endpoint_status[con->bsc_endp] = 0;
- bsc_mgcp_send_dlcx(con->bsc, con->bsc_endp, con->bsc->next_transaction++);
- bsc_mgcp_free_endpoint(con->bsc->nat, con->msc_endp);
- }
-
- bsc_mgcp_init(con);
-
-}
-
-/*
- * Search for the pending request
- */
-static void handle_dlcx_response(struct bsc_connection *bsc, struct msgb *msg,
- int code, const char *transaction)
-{
- uint32_t trans_id = UINT32_MAX;
- uint32_t b_ps, b_os, n_pr, n_or, jitter;
- int loss;
- struct bsc_nat_call_stats *tmp, *stat = NULL;
- struct ctrl_cmd *cmd;
-
- /* parse the transaction identifier */
- int rc = sscanf(transaction, "nat-%u", &trans_id);
- if (rc != 1) {
- LOGP(DNAT, LOGL_ERROR, "Can not parse transaction id: '%s'\n",
- transaction);
- return;
- }
-
- /* find the answer for the request we made */
- llist_for_each_entry(tmp, &bsc->pending_dlcx, entry) {
- if (trans_id != tmp->trans_id)
- continue;
-
- stat = tmp;
- break;
- }
-
- if (!stat) {
- LOGP(DNAT, LOGL_ERROR,
- "Can not find transaction for: %u\n", trans_id);
- return;
- }
-
- /* attempt to parse the data now */
- rc = mgcp_parse_stats(msg, &b_ps, &b_os, &n_pr, &n_or, &loss, &jitter);
- if (rc != 0)
- LOGP(DNAT, LOGL_ERROR,
- "Can not parse connection statistics: %d\n", rc);
-
- /* send a trap now */
- cmd = ctrl_cmd_create(bsc, CTRL_TYPE_TRAP);
- if (!cmd) {
- LOGP(DNAT, LOGL_ERROR,
- "Creating a ctrl cmd failed.\n");
- goto free_stat;
- }
-
- cmd->id = "0";
- cmd->variable = talloc_asprintf(cmd, "net.0.bsc.%d.call_stats.v2",
- bsc->cfg->nr);
- cmd->reply = talloc_asprintf(cmd,
- "mg_ip_addr=%s,mg_port=%d,",
- inet_ntoa(stat->net_addr),
- stat->net_rtp_port);
- cmd->reply = talloc_asprintf_append(cmd->reply,
- "endpoint_ip_addr=%s,endpoint_port=%d,",
- inet_ntoa(stat->bts_addr),
- stat->bts_rtp_port);
- cmd->reply = talloc_asprintf_append(cmd->reply,
- "nat_pkt_in=%u,nat_pkt_out=%u,"
- "nat_bytes_in=%u,nat_bytes_out=%u,"
- "nat_jitter=%u,nat_pkt_lost=%d,",
- stat->bts_pr, stat->net_ps,
- stat->bts_or, stat->net_os,
- stat->bts_jitter, stat->bts_loss);
- cmd->reply = talloc_asprintf_append(cmd->reply,
- "bsc_pkt_in=%u,bsc_pkt_out=%u,"
- "bsc_bytes_in=%u,bsc_bytes_out=%u,"
- "bsc_jitter=%u,bsc_pkt_lost=%d,",
- n_pr, b_ps,
- n_or, b_os,
- jitter, loss);
- cmd->reply = talloc_asprintf_append(cmd->reply,
- "sccp_src_ref=%u,sccp_dst_ref=%u",
- sccp_src_ref_to_int(&stat->src_ref),
- sccp_src_ref_to_int(&stat->remote_ref));
-
- /* send it and be done */
- ctrl_cmd_send_to_all(bsc->nat->ctrl, cmd);
- talloc_free(cmd);
-
-free_stat:
- bsc->pending_dlcx_count -= 1;
- llist_del(&stat->entry);
- talloc_free(stat);
-}
-
-
-struct nat_sccp_connection *bsc_mgcp_find_con(struct bsc_nat *nat, int endpoint)
-{
- struct nat_sccp_connection *con = NULL;
- struct nat_sccp_connection *sccp;
-
- llist_for_each_entry(sccp, &nat->sccp_connections, list_entry) {
- if (sccp->msc_endp == -1)
- continue;
- if (sccp->msc_endp != endpoint)
- continue;
-
- con = sccp;
- }
-
- if (con)
- return con;
-
- LOGP(DMGCP, LOGL_ERROR,
- "Failed to find the connection for endpoint: 0x%x\n", endpoint);
- return NULL;
-}
-
-static int nat_osmux_only(struct mgcp_config *mgcp_cfg, struct bsc_config *bsc_cfg)
-{
- if (mgcp_cfg->osmux == OSMUX_USAGE_ONLY)
- return 1;
- if (bsc_cfg->osmux == OSMUX_USAGE_ONLY)
- return 1;
- return 0;
-}
-
-static int bsc_mgcp_policy_cb(struct mgcp_trunk_config *tcfg, int endpoint, int state, const char *transaction_id)
-{
- struct bsc_nat *nat;
- struct bsc_endpoint *bsc_endp;
- struct nat_sccp_connection *sccp;
- struct mgcp_endpoint *mgcp_endp;
- struct msgb *bsc_msg;
-
- nat = tcfg->cfg->data;
- bsc_endp = &nat->bsc_endpoints[endpoint];
- mgcp_endp = &nat->mgcp_cfg->trunk.endpoints[endpoint];
-
- if (bsc_endp->transaction_id) {
- LOGP(DMGCP, LOGL_ERROR, "Endpoint 0x%x had pending transaction: '%s'\n",
- endpoint, bsc_endp->transaction_id);
- talloc_free(bsc_endp->transaction_id);
- bsc_endp->transaction_id = NULL;
- bsc_endp->transaction_state = 0;
- }
- bsc_endp->bsc = NULL;
-
- sccp = bsc_mgcp_find_con(nat, endpoint);
-
- if (!sccp) {
- LOGP(DMGCP, LOGL_ERROR, "Did not find BSC for change on endpoint: 0x%x state: %d\n", endpoint, state);
-
- switch (state) {
- case MGCP_ENDP_CRCX:
- return MGCP_POLICY_REJECT;
- break;
- case MGCP_ENDP_DLCX:
- return MGCP_POLICY_CONT;
- break;
- case MGCP_ENDP_MDCX:
- return MGCP_POLICY_CONT;
- break;
- default:
- LOGP(DMGCP, LOGL_FATAL, "Unhandled state: %d\n", state);
- return MGCP_POLICY_CONT;
- break;
- }
- }
-
- /* Allocate a Osmux circuit ID */
- if (state == MGCP_ENDP_CRCX) {
- if (nat->mgcp_cfg->osmux && sccp->bsc->cfg->osmux) {
- osmux_allocate_cid(mgcp_endp);
- if (mgcp_endp->osmux.allocated_cid < 0 &&
- nat_osmux_only(nat->mgcp_cfg, sccp->bsc->cfg)) {
- LOGP(DMGCP, LOGL_ERROR,
- "Rejecting usage of endpoint\n");
- return MGCP_POLICY_REJECT;
- }
- }
- }
-
- /* we need to generate a new and patched message */
- bsc_msg = bsc_mgcp_rewrite((char *) nat->mgcp_msg, nat->mgcp_length,
- sccp->bsc_endp, mgcp_bts_src_addr(mgcp_endp),
- mgcp_endp->bts_end.local_port,
- mgcp_endp->osmux.allocated_cid,
- &mgcp_endp->net_end.codec.payload_type,
- nat->sdp_ensure_amr_mode_set);
- if (!bsc_msg) {
- LOGP(DMGCP, LOGL_ERROR, "Failed to patch the msg.\n");
- return MGCP_POLICY_CONT;
- }
-
-
- bsc_endp->transaction_id = talloc_strdup(nat, transaction_id);
- bsc_endp->transaction_state = state;
- bsc_endp->bsc = sccp->bsc;
-
- /* we need to update some bits */
- if (state == MGCP_ENDP_CRCX) {
- struct sockaddr_in sock;
-
- /* Annotate the allocated Osmux CID until the bsc confirms that
- * it agrees to use Osmux for this voice flow.
- */
- if (mgcp_endp->osmux.allocated_cid >= 0 &&
- mgcp_endp->osmux.state != OSMUX_STATE_ENABLED) {
- mgcp_endp->osmux.state = OSMUX_STATE_NEGOTIATING;
- mgcp_endp->osmux.cid = mgcp_endp->osmux.allocated_cid;
- }
-
- socklen_t len = sizeof(sock);
- if (getpeername(sccp->bsc->write_queue.bfd.fd, (struct sockaddr *) &sock, &len) != 0) {
- LOGP(DMGCP, LOGL_ERROR, "Can not get the peername...%d/%s\n",
- errno, strerror(errno));
- } else {
- mgcp_endp->bts_end.addr = sock.sin_addr;
- }
-
- /* send the message and a fake MDCX to force sending of a dummy packet */
- bsc_write(sccp->bsc, bsc_msg, IPAC_PROTO_MGCP_OLD);
- bsc_mgcp_send_mdcx(sccp->bsc, sccp->bsc_endp, mgcp_endp);
- return MGCP_POLICY_DEFER;
- } else if (state == MGCP_ENDP_DLCX) {
- /* we will free the endpoint now and send a DLCX to the BSC */
- msgb_free(bsc_msg);
- bsc_mgcp_dlcx(sccp);
-
- /* libmgcp clears the MGCP endpoint for us */
- if (mgcp_endp->osmux.state == OSMUX_STATE_ENABLED)
- osmux_release_cid(mgcp_endp);
-
- return MGCP_POLICY_CONT;
- } else {
- bsc_write(sccp->bsc, bsc_msg, IPAC_PROTO_MGCP_OLD);
- return MGCP_POLICY_DEFER;
- }
-}
-
-/*
- * We do have a failure, free data downstream..
- */
-static void free_chan_downstream(struct mgcp_endpoint *endp, struct bsc_endpoint *bsc_endp,
- struct bsc_connection *bsc)
-{
- LOGP(DMGCP, LOGL_ERROR, "No CI, freeing endpoint 0x%x in state %d\n",
- ENDPOINT_NUMBER(endp), bsc_endp->transaction_state);
-
- /* if a CRCX failed... send a DLCX down the stream */
- if (bsc_endp->transaction_state == MGCP_ENDP_CRCX) {
- struct nat_sccp_connection *con;
- con = bsc_mgcp_find_con(bsc->nat, ENDPOINT_NUMBER(endp));
- if (!con) {
- LOGP(DMGCP, LOGL_ERROR,
- "No SCCP connection for endp 0x%x\n",
- ENDPOINT_NUMBER(endp));
- } else {
- if (con->bsc == bsc) {
- bsc_mgcp_send_dlcx(bsc, con->bsc_endp, con->bsc->next_transaction++);
- } else {
- LOGP(DMGCP, LOGL_ERROR,
- "Endpoint belongs to a different BSC\n");
- }
- }
- }
-
- bsc_mgcp_free_endpoint(bsc->nat, ENDPOINT_NUMBER(endp));
- mgcp_release_endp(endp);
-}
-
-static void bsc_mgcp_osmux_confirm(struct mgcp_endpoint *endp, const char *str)
-{
- unsigned int osmux_cid;
- char *res;
-
- res = strstr(str, "X-Osmux: ");
- if (!res) {
- LOGP(DMGCP, LOGL_INFO,
- "BSC doesn't want to use Osmux, failing back to RTP\n");
- goto err;
- }
-
- if (sscanf(res, "X-Osmux: %u", &osmux_cid) != 1) {
- LOGP(DMGCP, LOGL_ERROR, "Failed to parse Osmux CID '%s'\n",
- str);
- goto err;
- }
-
- if (endp->osmux.cid != osmux_cid) {
- LOGP(DMGCP, LOGL_ERROR,
- "BSC sent us wrong CID %u, we expected %u",
- osmux_cid, endp->osmux.cid);
- goto err;
- }
-
- LOGP(DMGCP, LOGL_NOTICE, "bsc accepted to use Osmux (cid=%u)\n",
- osmux_cid);
- endp->osmux.state = OSMUX_STATE_ACTIVATING;
- return;
-err:
- osmux_release_cid(endp);
- endp->osmux.state = OSMUX_STATE_DISABLED;
-}
-
-/*
- * We have received a msg from the BSC. We will see if we know
- * this transaction and if it belongs to the BSC. Then we will
- * need to patch the content to point to the local network and we
- * need to update the I: that was assigned by the BSS.
- *
- * Only responses to CRCX and DLCX should arrive here. The DLCX
- * needs to be handled specially to combine the two statistics.
- */
-void bsc_mgcp_forward(struct bsc_connection *bsc, struct msgb *msg)
-{
- struct msgb *output;
- struct bsc_endpoint *bsc_endp = NULL;
- struct mgcp_endpoint *endp = NULL;
- int i, code;
- char transaction_id[60];
-
- /* Some assumption that our buffer is big enough.. and null terminate */
- if (msgb_l2len(msg) > 2000) {
- LOGP(DMGCP, LOGL_ERROR, "MGCP message too long.\n");
- return;
- }
-
- msg->l2h[msgb_l2len(msg)] = '\0';
-
- if (bsc_mgcp_parse_response((const char *) msg->l2h, &code, transaction_id) != 0) {
- LOGP(DMGCP, LOGL_ERROR, "Failed to parse response code.\n");
- return;
- }
-
- for (i = 1; i < bsc->nat->mgcp_cfg->trunk.number_endpoints; ++i) {
- if (bsc->nat->bsc_endpoints[i].bsc != bsc)
- continue;
- /* no one listening? a bug? */
- if (!bsc->nat->bsc_endpoints[i].transaction_id)
- continue;
- if (strcmp(transaction_id, bsc->nat->bsc_endpoints[i].transaction_id) != 0)
- continue;
-
- endp = &bsc->nat->mgcp_cfg->trunk.endpoints[i];
- bsc_endp = &bsc->nat->bsc_endpoints[i];
- break;
- }
-
- if (!bsc_endp && strncmp("nat-", transaction_id, 4) == 0) {
- handle_dlcx_response(bsc, msg, code, transaction_id);
- return;
- }
-
- if (!bsc_endp) {
- LOGP(DMGCP, LOGL_ERROR, "Could not find active endpoint: %s for msg: '%s'\n",
- transaction_id, (const char *) msg->l2h);
- return;
- }
-
- endp->ci = bsc_mgcp_extract_ci((const char *) msg->l2h);
- if (endp->ci == CI_UNUSED) {
- free_chan_downstream(endp, bsc_endp, bsc);
- return;
- }
-
- if (endp->osmux.state == OSMUX_STATE_NEGOTIATING)
- bsc_mgcp_osmux_confirm(endp, (const char *) msg->l2h);
-
- /* If we require osmux and it is disabled.. fail */
- if (nat_osmux_only(bsc->nat->mgcp_cfg, bsc->cfg) &&
- endp->osmux.state == OSMUX_STATE_DISABLED) {
- LOGP(DMGCP, LOGL_ERROR,
- "Failed to activate osmux endpoint 0x%x\n",
- ENDPOINT_NUMBER(endp));
- free_chan_downstream(endp, bsc_endp, bsc);
- return;
- }
-
- /* free some stuff */
- talloc_free(bsc_endp->transaction_id);
- bsc_endp->transaction_id = NULL;
- bsc_endp->transaction_state = 0;
-
- /*
- * rewrite the information. In case the endpoint was deleted
- * there should be nothing for us to rewrite so putting endp->rtp_port
- * with the value of 0 should be no problem.
- */
- output = bsc_mgcp_rewrite((char * ) msg->l2h, msgb_l2len(msg), -1,
- mgcp_net_src_addr(endp),
- endp->net_end.local_port, -1,
- &endp->bts_end.codec.payload_type,
- bsc->nat->sdp_ensure_amr_mode_set);
- if (!output) {
- LOGP(DMGCP, LOGL_ERROR, "Failed to rewrite MGCP msg.\n");
- return;
- }
-
- mgcp_queue_for_call_agent(bsc->nat, output);
-}
-
-int bsc_mgcp_parse_response(const char *str, int *code, char transaction[60])
-{
- int rc;
- /* we want to parse two strings */
- rc = sscanf(str, "%3d %59s\n", code, transaction) != 2;
- transaction[59] = '\0';
- return rc;
-}
-
-uint32_t bsc_mgcp_extract_ci(const char *str)
-{
- unsigned int ci;
- char *res = strstr(str, "I: ");
- if (!res) {
- LOGP(DMGCP, LOGL_ERROR, "No CI in msg '%s'\n", str);
- return CI_UNUSED;
- }
-
- if (sscanf(res, "I: %u", &ci) != 1) {
- LOGP(DMGCP, LOGL_ERROR, "Failed to parse CI in msg '%s'\n", str);
- return CI_UNUSED;
- }
-
- return ci;
-}
-
-/**
- * Create a new MGCPCommand based on the input and endpoint from a message
- */
-static void patch_mgcp(struct msgb *output, const char *op, const char *tok,
- int endp, int len, int cr, int osmux_cid)
-{
- int slen;
- int ret;
- char buf[40];
- char osmux_extension[strlen("\nX-Osmux: 255") + 1];
-
- buf[0] = buf[39] = '\0';
- ret = sscanf(tok, "%*s %s", buf);
- if (ret != 1) {
- LOGP(DMGCP, LOGL_ERROR,
- "Failed to find Endpoint in: %s\n", tok);
- return;
- }
-
- if (osmux_cid >= 0)
- sprintf(osmux_extension, "\nX-Osmux: %u", osmux_cid & 0xff);
- else
- osmux_extension[0] = '\0';
-
- slen = sprintf((char *) output->l3h, "%s %s %x@mgw MGCP 1.0%s%s",
- op, buf, endp, osmux_extension, cr ? "\r\n" : "\n");
- output->l3h = msgb_put(output, slen);
-}
-
-/* we need to replace some strings... */
-struct msgb *bsc_mgcp_rewrite(char *input, int length, int endpoint,
- const char *ip, int port, int osmux_cid,
- int *first_payload_type, int ensure_mode_set)
-{
- static const char crcx_str[] = "CRCX ";
- static const char dlcx_str[] = "DLCX ";
- static const char mdcx_str[] = "MDCX ";
-
- static const char ip_str[] = "c=IN IP4 ";
- static const char aud_str[] = "m=audio ";
- static const char fmt_str[] = "a=fmtp:";
-
- char buf[128];
- char *running, *token;
- struct msgb *output;
-
- /* keep state to add the a=fmtp line */
- int found_fmtp = 0;
- int payload = -1;
- int cr = 1;
-
- if (length > 4096 - 256) {
- LOGP(DMGCP, LOGL_ERROR, "Input is too long.\n");
- return NULL;
- }
-
- output = msgb_alloc_headroom(4096, 128, "MGCP rewritten");
- if (!output) {
- LOGP(DMGCP, LOGL_ERROR, "Failed to allocate new MGCP msg.\n");
- return NULL;
- }
-
- running = input;
- output->l2h = output->data;
- output->l3h = output->l2h;
- for (token = strsep(&running, "\n"); running; token = strsep(&running, "\n")) {
- int len = strlen(token);
- cr = len > 0 && token[len - 1] == '\r';
-
- if (strncmp(crcx_str, token, (sizeof crcx_str) - 1) == 0) {
- patch_mgcp(output, "CRCX", token, endpoint, len, cr, osmux_cid);
- } else if (strncmp(dlcx_str, token, (sizeof dlcx_str) - 1) == 0) {
- patch_mgcp(output, "DLCX", token, endpoint, len, cr, -1);
- } else if (strncmp(mdcx_str, token, (sizeof mdcx_str) - 1) == 0) {
- patch_mgcp(output, "MDCX", token, endpoint, len, cr, -1);
- } else if (strncmp(ip_str, token, (sizeof ip_str) - 1) == 0) {
- output->l3h = msgb_put(output, strlen(ip_str));
- memcpy(output->l3h, ip_str, strlen(ip_str));
- output->l3h = msgb_put(output, strlen(ip));
- memcpy(output->l3h, ip, strlen(ip));
-
- if (cr) {
- output->l3h = msgb_put(output, 2);
- output->l3h[0] = '\r';
- output->l3h[1] = '\n';
- } else {
- output->l3h = msgb_put(output, 1);
- output->l3h[0] = '\n';
- }
- } else if (strncmp(aud_str, token, (sizeof aud_str) - 1) == 0) {
- int offset;
- if (sscanf(token, "m=audio %*d RTP/AVP %n%d", &offset, &payload) != 1) {
- LOGP(DMGCP, LOGL_ERROR, "Could not parsed audio line.\n");
- msgb_free(output);
- return NULL;
- }
-
- snprintf(buf, sizeof(buf)-1, "m=audio %d RTP/AVP %s\n",
- port, &token[offset]);
- buf[sizeof(buf)-1] = '\0';
-
- output->l3h = msgb_put(output, strlen(buf));
- memcpy(output->l3h, buf, strlen(buf));
- } else if (strncmp(fmt_str, token, (sizeof fmt_str) - 1) == 0) {
- found_fmtp = 1;
- goto copy;
- } else {
-copy:
- output->l3h = msgb_put(output, len + 1);
- memcpy(output->l3h, token, len);
- output->l3h[len] = '\n';
- }
- }
-
- /*
- * the above code made sure that we have 128 bytes lefts. So we can
- * safely append another line.
- */
- if (ensure_mode_set && !found_fmtp && payload != -1) {
- snprintf(buf, sizeof(buf) - 1, "a=fmtp:%d mode-set=2%s",
- payload, cr ? "\r\n" : "\n");
- buf[sizeof(buf) - 1] = '\0';
- output->l3h = msgb_put(output, strlen(buf));
- memcpy(output->l3h, buf, strlen(buf));
- }
-
- if (payload != -1 && first_payload_type)
- *first_payload_type = payload;
-
- return output;
-}
-
-/*
- * This comes from the MSC and we will now parse it. The caller needs
- * to free the msgb.
- */
-void bsc_nat_handle_mgcp(struct bsc_nat *nat, struct msgb *msg)
-{
- struct msgb *resp;
-
- if (!nat->mgcp_ipa) {
- LOGP(DMGCP, LOGL_ERROR, "MGCP message not allowed on IPA.\n");
- return;
- }
-
- if (msgb_l2len(msg) > sizeof(nat->mgcp_msg) - 1) {
- LOGP(DMGCP, LOGL_ERROR, "MGCP msg too big for handling.\n");
- return;
- }
-
- memcpy(nat->mgcp_msg, msg->l2h, msgb_l2len(msg));
- nat->mgcp_length = msgb_l2len(msg);
- nat->mgcp_msg[nat->mgcp_length] = '\0';
-
- /* now handle the message */
- resp = mgcp_handle_message(nat->mgcp_cfg, msg);
-
- /* we do have a direct answer... e.g. AUEP */
- if (resp)
- mgcp_queue_for_call_agent(nat, resp);
-
- return;
-}
-
-static int mgcp_do_read(struct osmo_fd *fd)
-{
- struct bsc_nat *nat;
- struct msgb *msg, *resp;
- int rc;
-
- nat = fd->data;
-
- rc = read(fd->fd, nat->mgcp_msg, sizeof(nat->mgcp_msg) - 1);
- if (rc <= 0) {
- LOGP(DMGCP, LOGL_ERROR, "Failed to read errno: %d\n", errno);
- return -1;
- }
-
- nat->mgcp_msg[rc] = '\0';
- nat->mgcp_length = rc;
-
- msg = msgb_alloc(sizeof(nat->mgcp_msg), "MGCP GW Read");
- if (!msg) {
- LOGP(DMGCP, LOGL_ERROR, "Failed to create buffer.\n");
- return -1;
- }
-
- msg->l2h = msgb_put(msg, rc);
- memcpy(msg->l2h, nat->mgcp_msg, msgb_l2len(msg));
- resp = mgcp_handle_message(nat->mgcp_cfg, msg);
- msgb_free(msg);
-
- /* we do have a direct answer... e.g. AUEP */
- if (resp)
- mgcp_queue_for_call_agent(nat, resp);
-
- return 0;
-}
-
-static int mgcp_do_write(struct osmo_fd *bfd, struct msgb *msg)
-{
- int rc;
-
- rc = write(bfd->fd, msg->data, msg->len);
-
- if (rc != msg->len) {
- LOGP(DMGCP, LOGL_ERROR, "Failed to write msg to MGCP CallAgent.\n");
- return -1;
- }
-
- return rc;
-}
-
-static int init_mgcp_socket(struct bsc_nat *nat, struct mgcp_config *cfg)
-{
- struct sockaddr_in addr;
- int on;
-
- cfg->gw_fd.bfd.fd = socket(AF_INET, SOCK_DGRAM, 0);
- if (cfg->gw_fd.bfd.fd < 0) {
- LOGP(DMGCP, LOGL_ERROR, "Failed to create MGCP socket. errno: %d\n", errno);
- return -1;
- }
-
- on = 1;
- setsockopt(cfg->gw_fd.bfd.fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
-
- memset(&addr, 0, sizeof(addr));
- addr.sin_family = AF_INET;
- addr.sin_port = htons(cfg->source_port);
- inet_aton(cfg->source_addr, &addr.sin_addr);
-
- if (bind(cfg->gw_fd.bfd.fd, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
- LOGP(DMGCP, LOGL_ERROR, "Failed to bind on %s:%d errno: %d\n",
- cfg->source_addr, cfg->source_port, errno);
- close(cfg->gw_fd.bfd.fd);
- cfg->gw_fd.bfd.fd = -1;
- return -1;
- }
-
- addr.sin_port = htons(2727);
- inet_aton(cfg->call_agent_addr, &addr.sin_addr);
- if (connect(cfg->gw_fd.bfd.fd, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
- LOGP(DMGCP, LOGL_ERROR, "Failed to connect to: '%s'. errno: %d\n",
- cfg->call_agent_addr, errno);
- close(cfg->gw_fd.bfd.fd);
- cfg->gw_fd.bfd.fd = -1;
- return -1;
- }
-
- osmo_wqueue_init(&cfg->gw_fd, 10);
- cfg->gw_fd.bfd.when = BSC_FD_READ;
- cfg->gw_fd.bfd.data = nat;
- cfg->gw_fd.read_cb = mgcp_do_read;
- cfg->gw_fd.write_cb = mgcp_do_write;
-
- if (osmo_fd_register(&cfg->gw_fd.bfd) != 0) {
- LOGP(DMGCP, LOGL_ERROR, "Failed to register MGCP fd.\n");
- close(cfg->gw_fd.bfd.fd);
- cfg->gw_fd.bfd.fd = -1;
- return -1;
- }
-
- return 0;
-}
-
-int bsc_mgcp_nat_init(struct bsc_nat *nat)
-{
- struct mgcp_config *cfg = nat->mgcp_cfg;
-
- if (!cfg->call_agent_addr) {
- LOGP(DMGCP, LOGL_ERROR, "The BSC nat requires the call agent ip to be set.\n");
- return -1;
- }
-
- if (cfg->bts_ip) {
- LOGP(DMGCP, LOGL_ERROR, "Do not set the BTS ip for the nat.\n");
- return -1;
- }
-
- /* initialize the MGCP socket */
- if (!nat->mgcp_ipa) {
- int rc = init_mgcp_socket(nat, cfg);
- if (rc != 0)
- return rc;
- }
-
-
- /* some more MGCP config handling */
- cfg->data = nat;
- cfg->policy_cb = bsc_mgcp_policy_cb;
-
- if (cfg->bts_ip)
- talloc_free(cfg->bts_ip);
- cfg->bts_ip = "";
-
- nat->bsc_endpoints = talloc_zero_array(nat,
- struct bsc_endpoint,
- cfg->trunk.number_endpoints + 1);
- if (!nat->bsc_endpoints) {
- LOGP(DMGCP, LOGL_ERROR, "Failed to allocate nat endpoints\n");
- close(cfg->gw_fd.bfd.fd);
- cfg->gw_fd.bfd.fd = -1;
- return -1;
- }
-
- if (mgcp_reset_transcoder(cfg) < 0) {
- LOGP(DMGCP, LOGL_ERROR, "Failed to send packet to the transcoder.\n");
- talloc_free(nat->bsc_endpoints);
- nat->bsc_endpoints = NULL;
- close(cfg->gw_fd.bfd.fd);
- cfg->gw_fd.bfd.fd = -1;
- return -1;
- }
-
- return 0;
-}
-
-void bsc_mgcp_clear_endpoints_for(struct bsc_connection *bsc)
-{
- struct rate_ctr *ctr = NULL;
- int i;
-
- if (bsc->cfg)
- ctr = &bsc->cfg->stats.ctrg->ctr[BCFG_CTR_DROPPED_CALLS];
-
- for (i = 1; i < bsc->nat->mgcp_cfg->trunk.number_endpoints; ++i) {
- struct bsc_endpoint *bsc_endp = &bsc->nat->bsc_endpoints[i];
-
- if (bsc_endp->bsc != bsc)
- continue;
-
- if (ctr)
- rate_ctr_inc(ctr);
-
- bsc_mgcp_free_endpoint(bsc->nat, i);
- mgcp_release_endp(&bsc->nat->mgcp_cfg->trunk.endpoints[i]);
- }
-}
generated by cgit v1.2.3 (git 2.25.1) at 2024-04-19 19:41:05 +0000