diff options
Diffstat (limited to 'src/libbsc/bsc_msc.c')
-rw-r--r-- | src/libbsc/bsc_msc.c | 320 |
1 files changed, 320 insertions, 0 deletions
diff --git a/src/libbsc/bsc_msc.c b/src/libbsc/bsc_msc.c new file mode 100644 index 000000000..82a572dbe --- /dev/null +++ b/src/libbsc/bsc_msc.c @@ -0,0 +1,320 @@ +/* Routines to talk to the MSC using the IPA Protocol */ +/* + * (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 <openbsc/bsc_msc.h> +#include <openbsc/debug.h> +#include <osmocom/abis/ipaccess.h> + +#include <osmocom/core/write_queue.h> +#include <osmocom/core/talloc.h> + +#include <osmocom/gsm/tlv.h> + +#include <arpa/inet.h> +#include <sys/socket.h> +#include <errno.h> +#include <fcntl.h> +#include <stdio.h> +#include <string.h> +#include <unistd.h> + +static void connection_loss(struct bsc_msc_connection *con) +{ + struct osmo_fd *fd; + + fd = &con->write_queue.bfd; + + if (con->pending_msg) { + LOGP(DMSC, LOGL_ERROR, + "MSC(%s) dropping incomplete message.\n", con->name); + msgb_free(con->pending_msg); + con->pending_msg = NULL; + } + + close(fd->fd); + fd->fd = -1; + fd->cb = osmo_wqueue_bfd_cb; + fd->when = 0; + + con->is_connected = 0; + con->first_contact = 0; + con->connection_loss(con); +} + +static void msc_con_timeout(void *_con) +{ + struct bsc_msc_connection *con = _con; + + LOGP(DMSC, LOGL_ERROR, + "MSC(%s) Connection timeout.\n", con->name); + bsc_msc_lost(con); +} + +/* called in the case of a non blocking connect */ +static int msc_connection_connect(struct osmo_fd *fd, unsigned int what) +{ + int rc; + int val; + struct bsc_msc_connection *con; + struct osmo_wqueue *queue; + + socklen_t len = sizeof(val); + + queue = container_of(fd, struct osmo_wqueue, bfd); + con = container_of(queue, struct bsc_msc_connection, write_queue); + + if ((what & BSC_FD_WRITE) == 0) { + LOGP(DMSC, LOGL_ERROR, + "MSC(%s) Callback but not writable.\n", con->name); + return -1; + } + + /* From here on we will either be connected or reconnect */ + osmo_timer_del(&con->timeout_timer); + + /* 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(%s) socket failed.\n", con->name); + goto error; + } + if (val != 0) { + LOGP(DMSC, LOGL_ERROR, + "Not connected to the MSC(%s): %d\n", + con->name, val); + goto error; + } + + + /* go to full operation */ + fd->cb = osmo_wqueue_bfd_cb; + fd->when = BSC_FD_READ | BSC_FD_EXCEPT; + + con->is_connected = 1; + LOGP(DMSC, LOGL_NOTICE, + "(Re)Connected to the MSC(%s).\n", con->name); + if (con->connected) + con->connected(con); + return 0; + +error: + osmo_fd_unregister(fd); + connection_loss(con); + return -1; +} +static void setnonblocking(struct osmo_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; + } +} + +int bsc_msc_connect(struct bsc_msc_connection *con) +{ + struct bsc_msc_dest *dest; + struct osmo_fd *fd; + struct sockaddr_in sin; + int on = 1, ret; + + if (llist_empty(con->dests)) { + LOGP(DMSC, LOGL_ERROR, + "No MSC(%s) connections configured.\n", + con->name); + connection_loss(con); + return -1; + } + + /* TODO: Why are we not using the libosmocore soecket + * abstraction, or libosmo-netif? */ + + /* move to the next connection */ + dest = (struct bsc_msc_dest *) con->dests->next; + llist_del(&dest->list); + llist_add_tail(&dest->list, con->dests); + + LOGP(DMSC, LOGL_NOTICE, + "Attempting to connect MSC(%s) at %s:%d\n", + con->name, dest->ip, dest->port); + + con->is_connected = 0; + + msgb_free(con->pending_msg); + con->pending_msg = NULL; + + fd = &con->write_queue.bfd; + fd->fd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP); + fd->priv_nr = 1; + + if (fd->fd < 0) { + perror("Creating TCP socket failed"); + return fd->fd; + } + + /* make it non blocking */ + setnonblocking(fd); + + /* set the socket priority */ + ret = setsockopt(fd->fd, IPPROTO_IP, IP_TOS, + &dest->dscp, sizeof(dest->dscp)); + if (ret != 0) + LOGP(DMSC, LOGL_ERROR, + "Failed to set DSCP to %d on MSC(%s). %s\n", + dest->dscp, con->name, strerror(errno)); + + memset(&sin, 0, sizeof(sin)); + sin.sin_family = AF_INET; + sin.sin_port = htons(dest->port); + inet_aton(dest->ip, &sin.sin_addr); + + ret = setsockopt(fd->fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)); + if (ret != 0) + LOGP(DMSC, LOGL_ERROR, + "Failed to set SO_REUSEADDR socket option\n"); + ret = connect(fd->fd, (struct sockaddr *) &sin, sizeof(sin)); + + if (ret == -1 && errno == EINPROGRESS) { + LOGP(DMSC, LOGL_ERROR, + "MSC(%s) Connection in progress\n", con->name); + fd->when = BSC_FD_WRITE; + fd->cb = msc_connection_connect; + osmo_timer_setup(&con->timeout_timer, msc_con_timeout, con); + osmo_timer_schedule(&con->timeout_timer, 20, 0); + } else if (ret < 0) { + perror("Connection failed"); + connection_loss(con); + return ret; + } else { + fd->when = BSC_FD_READ | BSC_FD_EXCEPT; + fd->cb = osmo_wqueue_bfd_cb; + con->is_connected = 1; + if (con->connected) + con->connected(con); + } + + ret = osmo_fd_register(fd); + if (ret < 0) { + perror("Registering the fd failed"); + close(fd->fd); + return ret; + } + + return ret; +} + +struct bsc_msc_connection *bsc_msc_create(void *ctx, struct llist_head *dests) +{ + struct bsc_msc_connection *con; + + con = talloc_zero(NULL, struct bsc_msc_connection); + if (!con) { + LOGP(DMSC, LOGL_FATAL, "Failed to create the MSC connection.\n"); + return NULL; + } + + con->dests = dests; + con->write_queue.bfd.fd = -1; + con->name = ""; + osmo_wqueue_init(&con->write_queue, 100); + return con; +} + +void bsc_msc_lost(struct bsc_msc_connection *con) +{ + osmo_wqueue_clear(&con->write_queue); + osmo_timer_del(&con->timeout_timer); + osmo_timer_del(&con->reconnect_timer); + + if (con->write_queue.bfd.fd >= 0) + osmo_fd_unregister(&con->write_queue.bfd); + connection_loss(con); +} + +static void reconnect_msc(void *_msc) +{ + struct bsc_msc_connection *con = _msc; + + LOGP(DMSC, LOGL_NOTICE, + "Attempting to reconnect to the MSC(%s).\n", con->name); + bsc_msc_connect(con); +} + +void bsc_msc_schedule_connect(struct bsc_msc_connection *con) +{ + LOGP(DMSC, LOGL_NOTICE, + "Attempting to reconnect to the MSC(%s)\n", con->name); + osmo_timer_setup(&con->reconnect_timer, reconnect_msc, con); + osmo_timer_schedule(&con->reconnect_timer, 5, 0); +} + +struct msgb *bsc_msc_id_get_resp(int fixed, const char *token, const uint8_t *res, int len) +{ + struct msgb *msg; + + if (!token) { + LOGP(DMSC, LOGL_ERROR, "No token specified.\n"); + return NULL; + } + + msg = msgb_alloc_headroom(4096, 128, "id resp"); + if (!msg) { + LOGP(DMSC, LOGL_ERROR, "Failed to create the message.\n"); + return NULL; + } + + /* + * The situation is bizarre. The encoding doesn't follow the + * TLV structure. It is more like a LV and old versions had + * it wrong but we want new versions to old servers so we + * introduce the quirk here. + */ + msg->l2h = msgb_v_put(msg, IPAC_MSGT_ID_RESP); + if (fixed) { + msgb_put_u8(msg, 0); + msgb_put_u8(msg, strlen(token) + 2); + msgb_tv_fixed_put(msg, IPAC_IDTAG_UNITNAME, strlen(token) + 1, (uint8_t *) token); + if (len > 0) { + msgb_put_u8(msg, 0); + msgb_put_u8(msg, len + 1); + msgb_tv_fixed_put(msg, 0x24, len, res); + } + } else { + msgb_l16tv_put(msg, strlen(token) + 1, + IPAC_IDTAG_UNITNAME, (uint8_t *) token); + } + + return msg; +} |