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authorHolger Hans Peter Freyther <zecke@selfish.org>2010-07-28 03:32:52 +0800
committerHolger Hans Peter Freyther <zecke@selfish.org>2010-07-28 03:36:32 +0800
commit97f66e2b534e2a54c63360a3f8134a0189c54e25 (patch)
tree903e34443767b09ef1d11575f8a1502f6295c7fd /src/msc_conn.c
Public release of the cellmgr_ng code to convert E1 to IPA SCCP
Diffstat (limited to 'src/msc_conn.c')
-rw-r--r--src/msc_conn.c594
1 files changed, 594 insertions, 0 deletions
diff --git a/src/msc_conn.c b/src/msc_conn.c
new file mode 100644
index 0000000..1e3357d
--- /dev/null
+++ b/src/msc_conn.c
@@ -0,0 +1,594 @@
+/* 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 <laf0rge1/debug.h>
+#include <laf0rge1/tlv.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);
+ }
+}
+
+static void close_msc(struct bsc_data *bsc)
+{
+ struct bsc_fd *bfd = &bsc->msc_connection.bfd;
+
+ close(bfd->fd);
+ bsc_unregister_fd(bfd);
+ bfd->fd = -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");
+ close_msc(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");
+ close_msc(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");
+
+ close_msc(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->closing = 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 = (u_int8_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:
+ bsc_unregister_fd(fd);
+ close(fd->fd);
+ fd->fd = -1;
+ fd->cb = write_queue_bfd_cb;
+ fd->when = 0;
+ release_bsc_resources(bsc);
+ bsc_del_timer(&bsc->ping_timeout);
+ bsc_del_timer(&bsc->pong_timeout);
+ 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 u_int8_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->closing = 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, (u_int8_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);
+}