| /* GSMTAP output for Osmocom Layer2 (will only work on the host PC) */ |
| /* |
| * (C) 2010 by Harald Welte <laforge@gnumonks.org> |
| * |
| * 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 "../config.h" |
| |
| #ifdef HAVE_SYS_SELECT_H |
| |
| #include <osmocom/core/gsmtap_util.h> |
| #include <osmocom/core/logging.h> |
| #include <osmocom/core/gsmtap.h> |
| #include <osmocom/core/msgb.h> |
| #include <osmocom/core/select.h> |
| #include <osmocom/gsm/protocol/gsm_04_08.h> |
| #include <osmocom/gsm/rsl.h> |
| |
| #include <arpa/inet.h> |
| #include <sys/socket.h> |
| #include <netinet/in.h> |
| |
| #include <stdio.h> |
| #include <unistd.h> |
| #include <stdint.h> |
| #include <string.h> |
| #include <errno.h> |
| |
| static struct osmo_fd gsmtap_bfd = { .fd = -1 }; |
| static struct osmo_fd gsmtap_sink_bfd = { .fd = -1 }; |
| static LLIST_HEAD(gsmtap_txqueue); |
| |
| uint8_t chantype_rsl2gsmtap(uint8_t rsl_chantype, uint8_t link_id) |
| { |
| uint8_t ret = GSMTAP_CHANNEL_UNKNOWN; |
| |
| switch (rsl_chantype) { |
| case RSL_CHAN_Bm_ACCHs: |
| ret = GSMTAP_CHANNEL_TCH_F; |
| break; |
| case RSL_CHAN_Lm_ACCHs: |
| ret = GSMTAP_CHANNEL_TCH_H; |
| break; |
| case RSL_CHAN_SDCCH4_ACCH: |
| ret = GSMTAP_CHANNEL_SDCCH4; |
| break; |
| case RSL_CHAN_SDCCH8_ACCH: |
| ret = GSMTAP_CHANNEL_SDCCH8; |
| break; |
| case RSL_CHAN_BCCH: |
| ret = GSMTAP_CHANNEL_BCCH; |
| break; |
| case RSL_CHAN_RACH: |
| ret = GSMTAP_CHANNEL_RACH; |
| break; |
| case RSL_CHAN_PCH_AGCH: |
| /* it could also be AGCH... */ |
| ret = GSMTAP_CHANNEL_PCH; |
| break; |
| } |
| |
| if (link_id & 0x40) |
| ret |= GSMTAP_CHANNEL_ACCH; |
| |
| return ret; |
| } |
| |
| /* receive a message from L1/L2 and put it in GSMTAP */ |
| struct msgb *gsmtap_makemsg(uint16_t arfcn, uint8_t ts, uint8_t chan_type, |
| uint8_t ss, uint32_t fn, int8_t signal_dbm, |
| uint8_t snr, const uint8_t *data, unsigned int len) |
| { |
| struct msgb *msg; |
| struct gsmtap_hdr *gh; |
| uint8_t *dst; |
| |
| msg = msgb_alloc(sizeof(*gh) + len, "gsmtap_tx"); |
| if (!msg) |
| return NULL; |
| |
| gh = (struct gsmtap_hdr *) msgb_put(msg, sizeof(*gh)); |
| |
| gh->version = GSMTAP_VERSION; |
| gh->hdr_len = sizeof(*gh)/4; |
| gh->type = GSMTAP_TYPE_UM; |
| gh->timeslot = ts; |
| gh->sub_slot = ss; |
| gh->arfcn = htons(arfcn); |
| gh->snr_db = snr; |
| gh->signal_dbm = signal_dbm; |
| gh->frame_number = htonl(fn); |
| gh->sub_type = chan_type; |
| gh->antenna_nr = 0; |
| |
| dst = msgb_put(msg, len); |
| memcpy(dst, data, len); |
| |
| return msg; |
| } |
| |
| /* receive a message from L1/L2 and put it in GSMTAP */ |
| int gsmtap_sendmsg(uint16_t arfcn, uint8_t ts, uint8_t chan_type, uint8_t ss, |
| uint32_t fn, int8_t signal_dbm, uint8_t snr, |
| const uint8_t *data, unsigned int len) |
| { |
| struct msgb *msg; |
| |
| /* gsmtap was never initialized, so don't try to send anything */ |
| if (gsmtap_bfd.fd == -1) |
| return 0; |
| |
| msg = gsmtap_makemsg(arfcn, ts, chan_type, ss, fn, signal_dbm, |
| snr, data, len); |
| if (!msg) |
| return -ENOMEM; |
| |
| msgb_enqueue(&gsmtap_txqueue, msg); |
| gsmtap_bfd.when |= BSC_FD_WRITE; |
| |
| return 0; |
| } |
| |
| /* Callback from select layer if we can write to the socket */ |
| static int gsmtap_fd_cb(struct osmo_fd *fd, unsigned int flags) |
| { |
| struct msgb *msg; |
| int rc; |
| |
| if (!(flags & BSC_FD_WRITE)) |
| return 0; |
| |
| msg = msgb_dequeue(&gsmtap_txqueue); |
| if (!msg) { |
| /* no more messages in the queue, disable READ cb */ |
| gsmtap_bfd.when = 0; |
| return 0; |
| } |
| rc = write(gsmtap_bfd.fd, msg->data, msg->len); |
| if (rc < 0) { |
| perror("writing msgb to gsmtap fd"); |
| msgb_free(msg); |
| return rc; |
| } |
| if (rc != msg->len) { |
| perror("short write to gsmtap fd"); |
| msgb_free(msg); |
| return -EIO; |
| } |
| |
| msgb_free(msg); |
| return 0; |
| } |
| |
| int gsmtap_init(uint32_t dst_ip) |
| { |
| int rc; |
| struct sockaddr_in sin; |
| |
| sin.sin_family = AF_INET; |
| sin.sin_port = htons(GSMTAP_UDP_PORT); |
| sin.sin_addr.s_addr = htonl(dst_ip); |
| |
| /* create socket */ |
| rc = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP); |
| if (rc < 0) { |
| perror("creating UDP socket"); |
| return rc; |
| } |
| gsmtap_bfd.fd = rc; |
| rc = connect(rc, (struct sockaddr *)&sin, sizeof(sin)); |
| if (rc < 0) { |
| perror("connecting UDP socket"); |
| close(gsmtap_bfd.fd); |
| gsmtap_bfd.fd = -1; |
| return rc; |
| } |
| |
| gsmtap_bfd.when = BSC_FD_WRITE; |
| gsmtap_bfd.cb = gsmtap_fd_cb; |
| gsmtap_bfd.data = NULL; |
| |
| return osmo_fd_register(&gsmtap_bfd); |
| } |
| |
| /* Callback from select layer if we can read from the sink socket */ |
| static int gsmtap_sink_fd_cb(struct osmo_fd *fd, unsigned int flags) |
| { |
| int rc; |
| uint8_t buf[4096]; |
| |
| if (!(flags & BSC_FD_READ)) |
| return 0; |
| |
| rc = read(fd->fd, buf, sizeof(buf)); |
| if (rc < 0) { |
| perror("reading from gsmtap sink fd"); |
| return rc; |
| } |
| /* simply discard any data arriving on the socket */ |
| |
| return 0; |
| } |
| |
| /* Create a local 'gsmtap sink' avoiding the UDP packets being rejected |
| * with ICMP reject messages */ |
| int gsmtap_sink_init(uint32_t bind_ip) |
| { |
| int rc; |
| struct sockaddr_in sin; |
| |
| sin.sin_family = AF_INET; |
| sin.sin_port = htons(GSMTAP_UDP_PORT); |
| sin.sin_addr.s_addr = htonl(bind_ip); |
| |
| rc = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP); |
| if (rc < 0) { |
| perror("creating UDP socket"); |
| return rc; |
| } |
| gsmtap_sink_bfd.fd = rc; |
| rc = bind(rc, (struct sockaddr *)&sin, sizeof(sin)); |
| if (rc < 0) { |
| perror("binding UDP socket"); |
| close(gsmtap_sink_bfd.fd); |
| gsmtap_sink_bfd.fd = -1; |
| return rc; |
| } |
| |
| gsmtap_sink_bfd.when = BSC_FD_READ; |
| gsmtap_sink_bfd.cb = gsmtap_sink_fd_cb; |
| gsmtap_sink_bfd.data = NULL; |
| |
| return osmo_fd_register(&gsmtap_sink_bfd); |
| |
| } |
| |
| #endif /* HAVE_SYS_SELECT_H */ |