bool socketActive()
{
// Check if GSMTap is enabled
if (!gConfig.defines("Control.GSMTAP.TargetIP"))
return false;
// Port configuration
unsigned port = GSMTAP_UDP_PORT; // default port for GSM-TAP
if (gConfig.defines("Control.GSMTAP.TargetPort"))
port = gConfig.getNum("Control.GSMTAP.TargetPort");
// Set socket destination
GSMTAPSocket.destination(port,gConfig.getStr("Control.GSMTAP.TargetIP").c_str());
return true;
}
void gWriteGSMTAP(unsigned ARFCN, unsigned TS, unsigned FN,
GSM::TypeAndOffset to, bool is_saach, bool ul_dln,
const BitVector& frame)
{
char buffer[MAX_UDP_LENGTH];
int ofs = 0;
// Check if GSMTap is enabled
if (!gConfig.defines("GSMTAP.TargetIP")) return;
// Port configuration
unsigned port = GSMTAP_UDP_PORT; // default port for GSM-TAP
if (gConfig.defines("GSMTAP.TargetPort"))
port = gConfig.getNum("GSMTAP.TargetPort");
// Set socket destination
GSMTAPSocket.destination(port,gConfig.getStr("GSMTAP.TargetIP").c_str());
// Decode TypeAndOffset
uint8_t stype, scn;
switch (to) {
case GSM::TDMA_BEACON_BCCH:
stype = GSMTAP_CHANNEL_BCCH;
scn = 0;
break;
case GSM::TDMA_BEACON_CCCH:
stype = GSMTAP_CHANNEL_CCCH;
scn = 0;
break;
case GSM::SDCCH_4_0:
case GSM::SDCCH_4_1:
case GSM::SDCCH_4_2:
case GSM::SDCCH_4_3:
stype = GSMTAP_CHANNEL_SDCCH4;
scn = to - GSM::SDCCH_4_0;
break;
case GSM::SDCCH_8_0:
case GSM::SDCCH_8_1:
case GSM::SDCCH_8_2:
case GSM::SDCCH_8_3:
case GSM::SDCCH_8_4:
case GSM::SDCCH_8_5:
case GSM::SDCCH_8_6:
case GSM::SDCCH_8_7:
stype = GSMTAP_CHANNEL_SDCCH8;
scn = to - GSM::SDCCH_8_0;
break;
case GSM::TCHF_0:
stype = GSMTAP_CHANNEL_TCH_F;
scn = 0;
break;
case GSM::TCHH_0:
case GSM::TCHH_1:
stype = GSMTAP_CHANNEL_TCH_H;
scn = to - GSM::TCHH_0;
break;
default:
stype = GSMTAP_CHANNEL_UNKNOWN;
scn = 0;
}
if (is_saach)
stype |= GSMTAP_CHANNEL_ACCH;
// Flags in ARFCN
if (gConfig.getNum("GSM.Band") == 1900)
ARFCN |= GSMTAP_ARFCN_F_PCS;
if (ul_dln)
ARFCN |= GSMTAP_ARFCN_F_UPLINK;
// Build header
struct gsmtap_hdr *header = (struct gsmtap_hdr *)buffer;
header->version = GSMTAP_VERSION;
header->hdr_len = sizeof(struct gsmtap_hdr) >> 2;
header->type = GSMTAP_TYPE_UM;
header->timeslot = TS;
header->arfcn = htons(ARFCN);
header->signal_dbm = 0; /* FIXME */
header->snr_db = 0; /* FIXME */
header->frame_number = htonl(FN);
header->sub_type = stype;
header->antenna_nr = 0;
header->sub_slot = scn;
header->res = 0;
ofs += sizeof(*header);
// Add frame data
frame.pack((unsigned char*)&buffer[ofs]);
ofs += (frame.size() + 7) >> 3;
// Write the GSMTAP packet
GSMTAPSocket.write(buffer, ofs);
}