| /* 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 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 <msc_connection.h> |
| #include <bsc_data.h> |
| #include <bsc_ussd.h> |
| #include <bss_patch.h> |
| #include <bsc_sccp.h> |
| #include <bssap_sccp.h> |
| #include <ipaccess.h> |
| #include <mtp_data.h> |
| #include <cellmgr_debug.h> |
| |
| #include <osmocore/talloc.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 msc_connection *bsc); |
| static void msc_send(struct msc_connection *bsc, struct msgb *msg, int proto); |
| static void msc_schedule_reconnect(struct msc_connection *bsc); |
| |
| int send_or_queue_bsc_msg(struct mtp_link_set *link, int sls, struct msgb *msg) |
| { |
| if (mtp_link_set_submit_sccp_data(link, sls, msg->l2h, msgb_l2len(msg)) != 0) |
| LOGP(DMSC, LOGL_ERROR, "Could not forward SCCP message.\n"); |
| return 0; |
| } |
| |
| void msc_close_connection(struct msc_connection *fw) |
| { |
| struct bsc_fd *bfd = &fw->msc_connection.bfd; |
| |
| close(bfd->fd); |
| bsc_unregister_fd(bfd); |
| bfd->fd = -1; |
| fw->msc_link_down = 1; |
| release_bsc_resources(fw); |
| bsc_del_timer(&fw->ping_timeout); |
| bsc_del_timer(&fw->pong_timeout); |
| bsc_del_timer(&fw->msc_timeout); |
| msc_schedule_reconnect(fw); |
| } |
| |
| static void msc_connect_timeout(void *_fw_data) |
| { |
| struct msc_connection *fw = _fw_data; |
| |
| LOGP(DMSC, LOGL_ERROR, "Timeout on the MSC connection.\n"); |
| msc_close_connection(fw); |
| } |
| |
| static void msc_pong_timeout(void *_fw_data) |
| { |
| struct msc_connection *fw = _fw_data; |
| LOGP(DMSC, LOGL_ERROR, "MSC didn't respond to ping. Closing.\n"); |
| msc_close_connection(fw); |
| } |
| |
| static void send_ping(struct msc_connection *fw) |
| { |
| 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(fw, msg, IPAC_PROTO_IPACCESS); |
| } |
| |
| static void msc_ping_timeout(void *_fw_data) |
| { |
| struct msc_connection *fw = _fw_data; |
| |
| if (fw->ping_time < 0) |
| return; |
| |
| send_ping(fw); |
| |
| /* send another ping in 20 seconds */ |
| bsc_schedule_timer(&fw->ping_timeout, fw->ping_time, 0); |
| |
| /* also start a pong timer */ |
| bsc_schedule_timer(&fw->pong_timeout, fw->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 msc_connection *fw; |
| struct msgb *msg; |
| |
| fw = bfd->data; |
| msg = ipaccess_read_msg(bfd, &error); |
| |
| 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(fw); |
| 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); |
| |
| /* initialize the networking. This includes sending a GSM08.08 message */ |
| if (hh->proto == IPAC_PROTO_IPACCESS) { |
| if (fw->first_contact) { |
| LOGP(DMSC, LOGL_NOTICE, "Connected to MSC. Sending reset.\n"); |
| bsc_del_timer(&fw->msc_timeout); |
| fw->first_contact = 0; |
| fw->msc_link_down = 0; |
| msc_send_reset(fw); |
| } |
| if (msg->l2h[0] == IPAC_MSGT_ID_GET && fw->token) { |
| msc_send_id_response(fw); |
| } else if (msg->l2h[0] == IPAC_MSGT_PONG) { |
| bsc_del_timer(&fw->pong_timeout); |
| } |
| } else if (hh->proto == IPAC_PROTO_SCCP) { |
| msc_dispatch_sccp(fw, msg); |
| } else if (hh->proto == NAT_MUX) { |
| mgcp_forward(fw, 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 msc_connection *fw; |
| |
| fw = fd->data; |
| |
| if (fd != &fw->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(&fw->msc_connection.msg_queue)) |
| fd->when |= BSC_FD_WRITE; |
| return 0; |
| |
| error: |
| msc_close_connection(fw); |
| return -1; |
| } |
| |
| static int 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 -1; |
| } |
| |
| flags |= O_NONBLOCK; |
| flags = fcntl(fd->fd, F_SETFL, flags); |
| if (flags < 0) { |
| perror("fcntl get failed"); |
| close(fd->fd); |
| fd->fd = -1; |
| return -1; |
| } |
| |
| return 0; |
| } |
| |
| 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 */ |
| if (setnonblocking(fd) != 0) |
| return -1; |
| |
| 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 msc_connection *fw = _data; |
| |
| bsc_del_timer(&fw->reconnect_timer); |
| fw->first_contact = 1; |
| |
| rc = connect_to_msc(&fw->msc_connection.bfd, fw->ip, 5000, fw->dscp); |
| if (rc < 0) { |
| fprintf(stderr, "Opening the MSC connection failed. Trying again\n"); |
| bsc_schedule_timer(&fw->reconnect_timer, RECONNECT_TIME); |
| return; |
| } |
| |
| fw->msc_timeout.cb = msc_connect_timeout; |
| fw->msc_timeout.data = fw; |
| bsc_schedule_timer(&fw->msc_timeout, fw->msc_time, 0); |
| } |
| |
| static void msc_schedule_reconnect(struct msc_connection *fw) |
| { |
| bsc_schedule_timer(&fw->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 msc_connection *fw, 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(&fw->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 msc_connection *fw) |
| { |
| int on; |
| struct sockaddr_in addr; |
| |
| fw->mgcp_agent.bfd.fd = socket(AF_INET, SOCK_DGRAM, 0); |
| if (fw->mgcp_agent.bfd.fd < 0) { |
| LOGP(DMGCP, LOGL_FATAL, "Failed to create UDP socket errno: %d\n", errno); |
| return -1; |
| } |
| |
| on = 1; |
| setsockopt(fw->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(fw->mgcp_agent.bfd.fd, (struct sockaddr *) &addr, sizeof(addr)) < 0) { |
| LOGP(DMGCP, LOGL_FATAL, "Failed to bind to any port.\n"); |
| close(fw->mgcp_agent.bfd.fd); |
| fw->mgcp_agent.bfd.fd = -1; |
| return -1; |
| } |
| |
| /* connect to the remote */ |
| addr.sin_port = htons(2427); |
| if (connect(fw->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(fw->mgcp_agent.bfd.fd); |
| fw->mgcp_agent.bfd.fd = -1; |
| return -1; |
| } |
| |
| write_queue_init(&fw->mgcp_agent, 10); |
| fw->mgcp_agent.bfd.data = fw; |
| fw->mgcp_agent.bfd.when = BSC_FD_READ; |
| fw->mgcp_agent.read_cb = mgcp_do_read; |
| fw->mgcp_agent.write_cb = mgcp_do_write; |
| |
| if (bsc_register_fd(&fw->mgcp_agent.bfd) != 0) { |
| LOGP(DMGCP, LOGL_FATAL, "Failed to register BFD\n"); |
| close(fw->mgcp_agent.bfd.fd); |
| fw->mgcp_agent.bfd.fd = -1; |
| return -1; |
| } |
| |
| return 0; |
| } |
| |
| static void msc_send(struct msc_connection *fw, struct msgb *msg, int proto) |
| { |
| if (fw->msc_link_down) { |
| LOGP(DMSC, LOGL_NOTICE, "Dropping data due lack of MSC connection.\n"); |
| msgb_free(msg); |
| return; |
| } |
| |
| ipaccess_prepend_header(msg, proto); |
| |
| if (write_queue_enqueue(&fw->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 msc_connection *fw, |
| struct sccp_source_reference *src, struct sccp_source_reference *dst) |
| { |
| struct msgb *msg; |
| |
| if (fw->msc_link_down) { |
| LOGP(DMSC, LOGL_NOTICE, "Not releasing connection due lack of connection.\n"); |
| return; |
| } |
| |
| msg = create_sccp_rlc(src, dst); |
| if (!msg) |
| return; |
| |
| msc_send(fw, msg, IPAC_PROTO_SCCP); |
| } |
| |
| void msc_send_reset(struct msc_connection *fw) |
| { |
| struct msgb *msg; |
| |
| if (fw->msc_link_down) { |
| LOGP(DMSC, LOGL_NOTICE, "Not sending reset due lack of connection.\n"); |
| return; |
| } |
| |
| msg = create_reset(); |
| if (!msg) |
| return; |
| |
| msc_send(fw, msg, IPAC_PROTO_SCCP); |
| msc_ping_timeout(fw); |
| } |
| |
| static void msc_send_id_response(struct msc_connection *fw) |
| { |
| 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(fw->token) + 1, |
| IPAC_IDTAG_UNITNAME, (uint8_t *) fw->token); |
| |
| msc_send(fw, msg, IPAC_PROTO_IPACCESS); |
| } |
| |
| void msc_send_direct(struct msc_connection *fw, struct msgb *msg) |
| { |
| return msc_send(fw, msg, IPAC_PROTO_SCCP); |
| } |
| |
| void msc_send_msg(struct msc_connection *fw, int rc, struct sccp_parse_result *result, struct msgb *_msg) |
| { |
| struct msgb *msg; |
| |
| if (fw->msc_connection.bfd.fd < 0) { |
| LOGP(DMSC, LOGL_ERROR, "No connection to the MSC. dropping\n"); |
| return; |
| } |
| |
| bsc_ussd_handle_out_msg(fw, result, _msg); |
| |
| 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(fw, msg, IPAC_PROTO_SCCP); |
| } |
| |
| struct msc_connection *msc_connection_create(struct bsc_data *bsc, int mgcp) |
| { |
| struct msc_connection *msc; |
| |
| msc = talloc_zero(NULL, struct msc_connection); |
| if (!msc) { |
| LOGP(DMSC, LOGL_ERROR, "Failed to allocate the MSC Connection.\n"); |
| return NULL; |
| } |
| |
| write_queue_init(&msc->msc_connection, 100); |
| msc->reconnect_timer.cb = msc_reconnect; |
| msc->reconnect_timer.data = msc; |
| msc->msc_connection.read_cb = ipaccess_a_fd_cb; |
| msc->msc_connection.write_cb = ipaccess_write_cb; |
| msc->msc_connection.bfd.data = msc; |
| msc->msc_link_down = 1; |
| |
| /* handle the timeout */ |
| msc->ping_timeout.cb = msc_ping_timeout; |
| msc->ping_timeout.data = msc; |
| msc->pong_timeout.cb = msc_pong_timeout; |
| msc->pong_timeout.data = msc; |
| |
| /* create MGCP port */ |
| if (mgcp && mgcp_create_port(msc) != 0) { |
| LOGP(DMSC, LOGL_ERROR, "Failed to bind for the MGCP port.\n"); |
| talloc_free(msc); |
| return NULL; |
| } |
| |
| INIT_LLIST_HEAD(&msc->sccp_connections); |
| llist_add(&msc->entry, &bsc->mscs); |
| msc->nr = bsc->num_mscs++; |
| |
| return msc; |
| } |
| |
| struct msc_connection *msc_connection_num(struct bsc_data *bsc, int num) |
| { |
| struct msc_connection *msc; |
| |
| llist_for_each_entry(msc, &bsc->mscs, entry) |
| if (msc->nr == num) |
| return msc; |
| return NULL; |
| } |
| |
| int msc_connection_start(struct msc_connection *msc) |
| { |
| if (msc->msc_connection.bfd.fd > 0) { |
| LOGP(DMSC, LOGL_ERROR, |
| "Function should not be called with active connection.\n"); |
| return -1; |
| } |
| |
| msc_schedule_reconnect(msc); |
| return 0; |
| } |