| /* MSC related stuff... */ |
| /* |
| * (C) 2010 by Holger Hans Peter Freyther <zecke@selfish.org> |
| * (C) 2010 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 General Public License as published by |
| * the Free Software Foundation; either version 2 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 General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License along |
| * with this program; if not, write to the Free Software Foundation, Inc., |
| * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| */ |
| |
| #include <bsc_data.h> |
| #include <bss_patch.h> |
| #include <bssap_sccp.h> |
| #include <ipaccess.h> |
| #include <mtp_data.h> |
| #include <cellmgr_debug.h> |
| |
| #include <osmocore/tlv.h> |
| #include <osmocore/utils.h> |
| |
| #include <arpa/inet.h> |
| #include <sys/socket.h> |
| #include <netinet/tcp.h> |
| |
| #include <fcntl.h> |
| #include <unistd.h> |
| #include <errno.h> |
| #include <string.h> |
| |
| #define RECONNECT_TIME 10, 0 |
| #define NAT_MUX 0xfc |
| |
| static void msc_send_id_response(struct bsc_data *bsc); |
| static void msc_send(struct bsc_data *bsc, struct msgb *msg, int proto); |
| |
| void mtp_link_slta_recv(struct mtp_link *link) |
| { |
| struct msgb *msg; |
| unsigned int sls; |
| |
| while (!llist_empty(&link->pending_msgs)) { |
| msg = msgb_dequeue(&link->pending_msgs); |
| sls = (unsigned int) msg->l3h; |
| |
| if (mtp_link_submit_sccp_data(link, sls, msg->l2h, msgb_l2len(msg)) != 0) |
| LOGP(DMSC, LOGL_ERROR, "Could not forward SCCP message.\n"); |
| |
| msgb_free(msg); |
| } |
| } |
| |
| void msc_clear_queue(struct bsc_data *data) |
| { |
| struct msgb *msg; |
| |
| LOGP(DMSC, LOGL_NOTICE, "Clearing the MSC to BSC queue.\n"); |
| while (!llist_empty(&data->link.the_link->pending_msgs)) { |
| msg = msgb_dequeue(&data->link.the_link->pending_msgs); |
| msgb_free(msg); |
| } |
| } |
| |
| void msc_close_connection(struct bsc_data *bsc) |
| { |
| struct bsc_fd *bfd = &bsc->msc_connection.bfd; |
| |
| close(bfd->fd); |
| bsc_unregister_fd(bfd); |
| bfd->fd = -1; |
| bsc->msc_link_down = 1; |
| release_bsc_resources(bsc); |
| bsc_del_timer(&bsc->ping_timeout); |
| bsc_del_timer(&bsc->pong_timeout); |
| } |
| |
| static void msc_connect_timeout(void *_bsc_data) |
| { |
| struct bsc_data *bsc_data = _bsc_data; |
| |
| LOGP(DMSC, LOGL_ERROR, "Timeout on the MSC connection.\n"); |
| msc_close_connection(bsc_data); |
| } |
| |
| static void msc_pong_timeout(void *_bsc_data) |
| { |
| struct bsc_data *bsc_data = _bsc_data; |
| LOGP(DMSC, LOGL_ERROR, "MSC didn't respond to ping. Closing.\n"); |
| msc_close_connection(bsc_data); |
| } |
| |
| static void send_ping(struct bsc_data *bsc) |
| { |
| struct msgb *msg; |
| |
| msg = msgb_alloc_headroom(4096, 128, "ping"); |
| if (!msg) { |
| LOGP(DMSC, LOGL_ERROR, "Failed to create PING.\n"); |
| return; |
| } |
| |
| msg->l2h = msgb_put(msg, 1); |
| msg->l2h[0] = IPAC_MSGT_PING; |
| |
| msc_send(bsc, msg, IPAC_PROTO_IPACCESS); |
| } |
| |
| static void msc_ping_timeout(void *_bsc_data) |
| { |
| struct bsc_data *bsc_data = _bsc_data; |
| |
| if (bsc_data->ping_time < 0) |
| return; |
| |
| send_ping(bsc_data); |
| |
| /* send another ping in 20 seconds */ |
| bsc_schedule_timer(&bsc_data->ping_timeout, bsc_data->ping_time, 0); |
| |
| /* also start a pong timer */ |
| bsc_schedule_timer(&bsc_data->pong_timeout, bsc_data->pong_time, 0); |
| } |
| |
| /* |
| * callback with IP access data |
| */ |
| static int ipaccess_a_fd_cb(struct bsc_fd *bfd) |
| { |
| int error; |
| struct ipaccess_head *hh; |
| struct mtp_link *link; |
| struct bsc_data *bsc; |
| struct msgb *msg; |
| |
| msg = ipaccess_read_msg(bfd, &error); |
| |
| bsc = (struct bsc_data *) bfd->data; |
| |
| if (!msg) { |
| if (error == 0) |
| fprintf(stderr, "The connection to the MSC was lost, exiting\n"); |
| else |
| fprintf(stderr, "Error in the IPA stream.\n"); |
| |
| msc_close_connection(bsc); |
| return -1; |
| } |
| |
| LOGP(DMSC, LOGL_DEBUG, "From MSC: %s proto: %d\n", hexdump(msg->data, msg->len), msg->l2h[0]); |
| |
| /* handle base message handling */ |
| hh = (struct ipaccess_head *) msg->data; |
| ipaccess_rcvmsg_base(msg, bfd); |
| |
| link = bsc->link.the_link; |
| |
| /* initialize the networking. This includes sending a GSM08.08 message */ |
| if (hh->proto == IPAC_PROTO_IPACCESS) { |
| if (bsc->first_contact) { |
| LOGP(DMSC, LOGL_NOTICE, "Connected to MSC. Sending reset.\n"); |
| bsc_del_timer(&bsc->msc_timeout); |
| bsc->first_contact = 0; |
| bsc->msc_link_down = 0; |
| msc_send_reset(bsc); |
| } |
| if (msg->l2h[0] == IPAC_MSGT_ID_GET && bsc->token) { |
| msc_send_id_response(bsc); |
| } else if (msg->l2h[0] == IPAC_MSGT_PONG) { |
| bsc_del_timer(&bsc->pong_timeout); |
| } |
| } else if (hh->proto == IPAC_PROTO_SCCP) { |
| struct sccp_parse_result result; |
| int rc; |
| rc = bss_patch_filter_msg(msg, &result); |
| |
| if (rc == BSS_FILTER_RESET_ACK) { |
| LOGP(DMSC, LOGL_NOTICE, "Filtering reset ack from the MSC\n"); |
| } else if (rc == BSS_FILTER_RLSD) { |
| LOGP(DMSC, LOGL_DEBUG, "Filtering RLSD from the MSC\n"); |
| update_con_state(rc, &result, msg, 1, 0); |
| } else if (rc == BSS_FILTER_RLC) { |
| /* if we receive this we have forwarded a RLSD to the network */ |
| LOGP(DMSC, LOGL_ERROR, "RLC from the network. BAD!\n"); |
| } else if (rc == BSS_FILTER_CLEAR_COMPL) { |
| LOGP(DMSC, LOGL_ERROR, "Clear Complete from the network.\n"); |
| } else if (link->sccp_up) { |
| unsigned int sls; |
| |
| update_con_state(rc, &result, msg, 1, 0); |
| sls = sls_for_src_ref(result.destination_local_reference); |
| |
| /* patch a possible PC */ |
| bss_rewrite_header_to_bsc(msg, link->opc, link->dpc); |
| |
| /* we can not forward it right now */ |
| if (link->sltm_pending) { |
| LOGP(DMSC, LOGL_NOTICE, "Queueing msg for pending SLTM.\n"); |
| msg->l3h = (uint8_t *) sls; |
| msgb_enqueue(&link->pending_msgs, msg); |
| return 0; |
| } |
| |
| if (mtp_link_submit_sccp_data(link, sls, msg->l2h, msgb_l2len(msg)) != 0) |
| LOGP(DMSC, LOGL_ERROR, "Could not forward SCCP message.\n"); |
| } |
| } else if (hh->proto == NAT_MUX) { |
| mgcp_forward(bsc, msg->l2h, msgb_l2len(msg)); |
| } else { |
| LOGP(DMSC, LOGL_ERROR, "Unknown IPA proto 0x%x\n", hh->proto); |
| } |
| |
| msgb_free(msg); |
| return 0; |
| } |
| |
| static int ipaccess_write_cb(struct bsc_fd *fd, struct msgb *msg) |
| { |
| int rc; |
| |
| LOGP(DMSC, LOGL_DEBUG, "Sending to MSC: %s\n", hexdump(msg->data, msg->len)); |
| rc = write(fd->fd, msg->data, msg->len); |
| if (rc != msg->len) |
| LOGP(DMSC, LOGL_ERROR, "Could not write to MSC.\n"); |
| |
| return rc; |
| } |
| |
| /* called in the case of a non blocking connect */ |
| static int msc_connection_connect(struct bsc_fd *fd, unsigned int what) |
| { |
| int rc; |
| int val; |
| socklen_t len = sizeof(val); |
| struct bsc_data *bsc; |
| |
| bsc = (struct bsc_data *) fd->data; |
| |
| if (fd != &bsc->msc_connection.bfd) { |
| LOGP(DMSC, LOGL_ERROR, "This is only working with the MSC connection.\n"); |
| return -1; |
| } |
| |
| if ((what & BSC_FD_WRITE) == 0) |
| return -1; |
| |
| /* check the socket state */ |
| rc = getsockopt(fd->fd, SOL_SOCKET, SO_ERROR, &val, &len); |
| if (rc != 0) { |
| LOGP(DMSC, LOGL_ERROR, "getsockopt for the MSC socket failed.\n"); |
| goto error; |
| } |
| if (val != 0) { |
| LOGP(DMSC, LOGL_ERROR, "Not connected to the MSC.\n"); |
| goto error; |
| } |
| |
| |
| /* go to full operation */ |
| fd->cb = write_queue_bfd_cb; |
| fd->when = BSC_FD_READ; |
| if (!llist_empty(&bsc->msc_connection.msg_queue)) |
| fd->when |= BSC_FD_WRITE; |
| return 0; |
| |
| error: |
| msc_close_connection(bsc); |
| return -1; |
| } |
| |
| static void setnonblocking(struct bsc_fd *fd) |
| { |
| int flags; |
| |
| flags = fcntl(fd->fd, F_GETFL); |
| if (flags < 0) { |
| perror("fcntl get failed"); |
| close(fd->fd); |
| fd->fd = -1; |
| return; |
| } |
| |
| flags |= O_NONBLOCK; |
| flags = fcntl(fd->fd, F_SETFL, flags); |
| if (flags < 0) { |
| perror("fcntl get failed"); |
| close(fd->fd); |
| fd->fd = -1; |
| return; |
| } |
| } |
| |
| static int connect_to_msc(struct bsc_fd *fd, const char *ip, int port, int tos) |
| { |
| struct sockaddr_in sin; |
| int on = 1, ret; |
| |
| LOGP(DMSC, LOGL_NOTICE, "Attempting to connect MSC at %s:%d\n", ip, port); |
| |
| fd->fd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP); |
| |
| if (fd->fd < 0) { |
| perror("Creating TCP socket failed"); |
| return fd->fd; |
| } |
| |
| /* make it non blocking */ |
| setnonblocking(fd); |
| |
| memset(&sin, 0, sizeof(sin)); |
| sin.sin_family = AF_INET; |
| sin.sin_port = htons(port); |
| inet_aton(ip, &sin.sin_addr); |
| |
| setsockopt(fd->fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)); |
| ret = setsockopt(fd->fd, IPPROTO_TCP, TCP_NODELAY, &on, sizeof(on)); |
| if (ret != 0) |
| LOGP(DMSC, LOGL_ERROR, "Failed to set TCP_NODELAY: %s\n", strerror(errno)); |
| ret = setsockopt(fd->fd, IPPROTO_IP, IP_TOS, &tos, sizeof(tos)); |
| if (ret != 0) |
| LOGP(DMSC, LOGL_ERROR, "Failed to set IP_TOS: %s\n", strerror(errno)); |
| |
| ret = connect(fd->fd, (struct sockaddr *) &sin, sizeof(sin)); |
| |
| if (ret == -1 && errno == EINPROGRESS) { |
| LOGP(DMSC, LOGL_ERROR, "MSC Connection in progress\n"); |
| fd->when = BSC_FD_WRITE; |
| fd->cb = msc_connection_connect; |
| } else if (ret < 0) { |
| perror("Connection failed"); |
| close(fd->fd); |
| fd->fd = -1; |
| return ret; |
| } else { |
| fd->when = BSC_FD_READ; |
| fd->cb = write_queue_bfd_cb; |
| } |
| |
| ret = bsc_register_fd(fd); |
| if (ret < 0) { |
| perror("Registering the fd failed"); |
| close(fd->fd); |
| fd->fd = -1; |
| return ret; |
| } |
| |
| return ret; |
| } |
| |
| static void msc_reconnect(void *_data) |
| { |
| int rc; |
| struct bsc_data *bsc = (struct bsc_data *) _data; |
| |
| bsc_del_timer(&bsc->reconnect_timer); |
| bsc->first_contact = 1; |
| |
| rc = connect_to_msc(&bsc->msc_connection.bfd, bsc->msc_address, 5000, bsc->msc_ip_dscp); |
| if (rc < 0) { |
| fprintf(stderr, "Opening the MSC connection failed. Trying again\n"); |
| bsc_schedule_timer(&bsc->reconnect_timer, RECONNECT_TIME); |
| return; |
| } |
| |
| bsc->msc_timeout.cb = msc_connect_timeout; |
| bsc->msc_timeout.data = bsc; |
| bsc_schedule_timer(&bsc->msc_timeout, bsc->msc_time, 0); |
| } |
| |
| void msc_schedule_reconnect(struct bsc_data *bsc) |
| { |
| bsc_schedule_timer(&bsc->reconnect_timer, RECONNECT_TIME); |
| } |
| |
| /* |
| * mgcp forwarding is below |
| */ |
| static int mgcp_do_write(struct bsc_fd *fd, struct msgb *msg) |
| { |
| int ret; |
| |
| LOGP(DMGCP, LOGL_DEBUG, "Sending msg to MGCP GW size: %u\n", msg->len); |
| |
| ret = write(fd->fd, msg->data, msg->len); |
| if (ret != msg->len) |
| LOGP(DMGCP, LOGL_ERROR, "Failed to forward message to MGCP GW (%s).\n", strerror(errno)); |
| |
| return ret; |
| } |
| |
| static int mgcp_do_read(struct bsc_fd *fd) |
| { |
| struct msgb *mgcp; |
| int ret; |
| |
| mgcp = msgb_alloc_headroom(4096, 128, "mgcp_from_gw"); |
| if (!mgcp) { |
| LOGP(DMGCP, LOGL_ERROR, "Failed to allocate MGCP message.\n"); |
| return -1; |
| } |
| |
| ret = read(fd->fd, mgcp->data, 4096 - 128); |
| if (ret <= 0) { |
| LOGP(DMGCP, LOGL_ERROR, "Failed to read: %d/%s\n", errno, strerror(errno)); |
| msgb_free(mgcp); |
| return -1; |
| } else if (ret > 4096 - 128) { |
| LOGP(DMGCP, LOGL_ERROR, "Too much data: %d\n", ret); |
| msgb_free(mgcp); |
| return -1; |
| } |
| |
| mgcp->l2h = msgb_put(mgcp, ret); |
| msc_send(fd->data, mgcp, NAT_MUX); |
| return 0; |
| } |
| |
| void mgcp_forward(struct bsc_data *bsc, const uint8_t *data, unsigned int length) |
| { |
| struct msgb *mgcp; |
| |
| if (length > 4096) { |
| LOGP(DMGCP, LOGL_ERROR, "Can not forward too big message.\n"); |
| return; |
| } |
| |
| mgcp = msgb_alloc(4096, "mgcp_to_gw"); |
| if (!mgcp) { |
| LOGP(DMGCP, LOGL_ERROR, "Failed to send message.\n"); |
| return; |
| } |
| |
| msgb_put(mgcp, length); |
| memcpy(mgcp->data, data, mgcp->len); |
| if (write_queue_enqueue(&bsc->mgcp_agent, mgcp) != 0) { |
| LOGP(DMGCP, LOGL_FATAL, "Could not queue message to MGCP GW.\n"); |
| msgb_free(mgcp); |
| } |
| } |
| |
| static int mgcp_create_port(struct bsc_data *bsc) |
| { |
| int on; |
| struct sockaddr_in addr; |
| |
| bsc->mgcp_agent.bfd.fd = socket(AF_INET, SOCK_DGRAM, 0); |
| if (bsc->mgcp_agent.bfd.fd < 0) { |
| LOGP(DMGCP, LOGL_FATAL, "Failed to create UDP socket errno: %d\n", errno); |
| return -1; |
| } |
| |
| on = 1; |
| setsockopt(bsc->mgcp_agent.bfd.fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)); |
| |
| /* try to bind the socket */ |
| memset(&addr, 0, sizeof(addr)); |
| addr.sin_family = AF_INET; |
| addr.sin_addr.s_addr = htonl(INADDR_LOOPBACK); |
| addr.sin_port = 0; |
| |
| if (bind(bsc->mgcp_agent.bfd.fd, (struct sockaddr *) &addr, sizeof(addr)) < 0) { |
| LOGP(DMGCP, LOGL_FATAL, "Failed to bind to any port.\n"); |
| close(bsc->mgcp_agent.bfd.fd); |
| bsc->mgcp_agent.bfd.fd = -1; |
| return -1; |
| } |
| |
| /* connect to the remote */ |
| addr.sin_port = htons(2427); |
| if (connect(bsc->mgcp_agent.bfd.fd, (struct sockaddr *) & addr, sizeof(addr)) < 0) { |
| LOGP(DMGCP, LOGL_FATAL, "Failed to connect to local MGCP GW. %s\n", strerror(errno)); |
| close(bsc->mgcp_agent.bfd.fd); |
| bsc->mgcp_agent.bfd.fd = -1; |
| return -1; |
| } |
| |
| write_queue_init(&bsc->mgcp_agent, 10); |
| bsc->mgcp_agent.bfd.data = bsc; |
| bsc->mgcp_agent.bfd.when = BSC_FD_READ; |
| bsc->mgcp_agent.read_cb = mgcp_do_read; |
| bsc->mgcp_agent.write_cb = mgcp_do_write; |
| |
| if (bsc_register_fd(&bsc->mgcp_agent.bfd) != 0) { |
| LOGP(DMGCP, LOGL_FATAL, "Failed to register BFD\n"); |
| close(bsc->mgcp_agent.bfd.fd); |
| bsc->mgcp_agent.bfd.fd = -1; |
| return -1; |
| } |
| |
| return 0; |
| } |
| |
| int msc_init(struct bsc_data *bsc) |
| { |
| write_queue_init(&bsc->msc_connection, 100); |
| bsc->reconnect_timer.cb = msc_reconnect; |
| bsc->reconnect_timer.data = bsc; |
| bsc->msc_connection.read_cb = ipaccess_a_fd_cb; |
| bsc->msc_connection.write_cb = ipaccess_write_cb; |
| bsc->msc_connection.bfd.data = bsc; |
| bsc->msc_link_down = 1; |
| |
| /* handle the timeout */ |
| bsc->ping_timeout.cb = msc_ping_timeout; |
| bsc->ping_timeout.data = bsc; |
| bsc->pong_timeout.cb = msc_pong_timeout; |
| bsc->pong_timeout.data = bsc; |
| |
| /* create MGCP port */ |
| if (mgcp_create_port(bsc) != 0) |
| return -1; |
| return 0; |
| } |
| |
| static void msc_send(struct bsc_data *bsc, struct msgb *msg, int proto) |
| { |
| ipaccess_prepend_header(msg, proto); |
| |
| if (write_queue_enqueue(&bsc->msc_connection, msg) != 0) { |
| LOGP(DMSC, LOGL_FATAL, "Failed to queue MSG for the MSC.\n"); |
| msgb_free(msg); |
| return; |
| } |
| } |
| |
| void msc_send_rlc(struct bsc_data *bsc, |
| struct sccp_source_reference *src, struct sccp_source_reference *dst) |
| { |
| struct msgb *msg; |
| |
| msg = create_sccp_rlc(src, dst); |
| if (!msg) |
| return; |
| |
| msc_send(bsc, msg, IPAC_PROTO_SCCP); |
| } |
| |
| void msc_send_reset(struct bsc_data *bsc) |
| { |
| struct msgb *msg; |
| |
| msg = create_reset(); |
| if (!msg) |
| return; |
| |
| msc_send(bsc, msg, IPAC_PROTO_SCCP); |
| msc_ping_timeout(bsc); |
| } |
| |
| static void msc_send_id_response(struct bsc_data *bsc) |
| { |
| struct msgb *msg; |
| |
| msg = msgb_alloc_headroom(4096, 128, "id resp"); |
| msg->l2h = msgb_v_put(msg, IPAC_MSGT_ID_RESP); |
| msgb_l16tv_put(msg, strlen(bsc->token) + 1, |
| IPAC_IDTAG_UNITNAME, (uint8_t *) bsc->token); |
| |
| msc_send(bsc, msg, IPAC_PROTO_IPACCESS); |
| } |
| |
| void msc_send_msg(struct bsc_data *bsc, int rc, struct sccp_parse_result *result, struct msgb *_msg) |
| { |
| struct msgb *msg; |
| |
| if (bsc->msc_connection.bfd.fd < 0) { |
| LOGP(DMSC, LOGL_ERROR, "No connection to the MSC. dropping\n"); |
| return; |
| } |
| |
| msg = msgb_alloc_headroom(4096, 128, "SCCP to MSC"); |
| if (!msg) { |
| LOGP(DMSC, LOGL_ERROR, "Failed to alloc MSC msg.\n"); |
| return; |
| } |
| |
| bss_rewrite_header_for_msc(rc, msg, _msg, result); |
| msc_send(bsc, msg, IPAC_PROTO_SCCP); |
| } |