struct msgb *parse_rawmsg(uint8_t *data, uint16_t len_msg, uint8_t **searchmsg_p)
{
struct msgb *msg = NULL;
uint8_t *frame_p;
if(*searchmsg_p &&
(frame_p = memmem(data, len_msg, *searchmsg_p, SEARCHLEN))) {
*searchmsg_p = NULL;
msg = gsmtap_makemsg(0, 0, GSMTAP_CHANNEL_SDCCH,
0, 0, 0, 0, frame_p - 3, 23);
} else if((frame_p = memmem(data, len_msg, "\x25\x06\x06", 3))) {
msg = gsmtap_makemsg(0, 0, guess_chantype(frame_p + 0x0d),
0, 0, 0, 0, frame_p + 0x0d, 23);
}
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;
}
/*
* 142 bit
*/
int
GS_process(GS_CTX *ctx, int ts, int type, const unsigned char *src, int fn, int first_burst)
{
int bsic;
int ret;
unsigned char *data;
int len;
struct gs_ts_ctx *ts_ctx = &ctx->ts_ctx[ts];
memset(ctx->msg, 0, sizeof(ctx->msg));
if (ts_ctx->type == TST_TCHF && type == NORMAL &&
(fn % 26) != 12 && (fn % 26) != 25) {
/* Dieter: we came here because the burst might contain FACCH bits */
ctx->fn = fn;
/* get burst index to TCH bursts only */
ts_ctx->burst_count2 = fn % 26;
if (ts_ctx->burst_count2 >= 12)
ts_ctx->burst_count2--;
ts_ctx->burst_count2 = ts_ctx->burst_count2 % 8;
/* copy data bits and stealing flags to buffer */
memcpy(ts_ctx->burst2 + (116 * ts_ctx->burst_count2), src, 58);
memcpy(ts_ctx->burst2 + (116 * ts_ctx->burst_count2) + 58, src + 58 + 26, 58);
/* Return if not enough bursts for a full gsm message */
if ((ts_ctx->burst_count2 % 4) != 3)
return 0;
data = decode_facch(ctx, ts_ctx->burst2, &len, (ts_ctx->burst_count2 == 3) ? 1 : 0);
if (data == NULL) {
DEBUGF("cannot decode FACCH fnr=%d ts=%d\n", ctx->fn, ts);
return -1;
}
out_gsmdecode(0, 0, ts, ctx->fn, data, len);
if (ctx->gsmtap_fd >= 0) {
struct msgb *msg;
uint8_t chan_type = GSMTAP_CHANNEL_TCH_F;
uint8_t ss = 0;
int fn = (ctx->fn - 3); /* "- 3" for start of frame */
msg = gsmtap_makemsg(0, ts, chan_type, ss, ctx->fn, 0, 0, data, len);
if (msg)
write(ctx->gsmtap_fd, msg->data, msg->len);
}
return 0;
}
/* normal burst processing */
if (first_burst) /* Dieter: it is important to start with the correct burst */
ts_ctx->burst_count = 0;
ctx->fn = fn;
if (type == NORMAL) {
/* Interested in these frame numbers (cch)
* 2-5, 12-15, 22-25, 23-35, 42-45
* 6-9, 16-19, 26-29, 36-39, 46-49
*/
/* Copy content data into new array */
//DEBUGF("burst count %d\n", ctx->burst_count);
memcpy(ts_ctx->burst + (116 * ts_ctx->burst_count), src, 58);
memcpy(ts_ctx->burst + (116 * ts_ctx->burst_count) + 58, src + 58 + 26, 58);
ts_ctx->burst_count++;
/* Return if not enough bursts for a full gsm message */
if (ts_ctx->burst_count < 4)
return 0;
ts_ctx->burst_count = 0;
data = decode_cch(ctx, ts_ctx->burst, &len);
if (data == NULL) {
DEBUGF("cannot decode fnr=0x%06x (%6d) ts=%d\n", ctx->fn, ctx->fn, ts);
return -1;
}
//DEBUGF("OK TS %d, len %d\n", ts, len);
out_gsmdecode(0, 0, ts, ctx->fn, data, len);
if (ctx->gsmtap_fd >= 0) {
/* Dieter: set channel type according to configuration */
struct msgb *msg;
uint8_t chan_type = GSMTAP_CHANNEL_BCCH;
uint8_t ss = 0;
int fn = (ctx->fn - 3); /* "- 3" for start of frame */
chan_type = get_chan_type(ts_ctx->type, fn, &ss);
/* arfcn, ts, chan_type, ss, fn, signal, snr, data, len */
msg = gsmtap_makemsg(0, ts, chan_type, ss,
ctx->fn, 0, 0, data, len);
if (msg)
write(ctx->gsmtap_fd, msg->data,
msg->len);
}
#if 0
if (ctx->fn % 51 != 0) && ( (((ctx->fn % 51 + 5) % 10 == 0) || (((ctx->fn % 51) + 1) % 10 ==0) ) )
ready = 1;
#endif
return 0;
}
struct msgb *make_gsml2_msg(uint8_t gsmtap_chan, uint8_t *msg_start,
uint16_t msg_len, uint8_t **dummy)
{
return gsmtap_makemsg(0, 0, gsmtap_chan, 0, 0, 0, 0, msg_start, msg_len);
}
