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fix parsing of slot granting in RESOURCE MAC PDU

This commit is contained in:
Harald Welte 2011-04-24 07:51:31 +02:00
parent 5c14298646
commit 8c2db3d630
2 changed files with 46 additions and 7 deletions
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47
src/tetra_mac_pdu.c
View File

@ -116,6 +116,30 @@ static int decode_chan_alloc(struct tetra_chan_alloc_decoded *cad, const uint8_t
return cur - bits;
}
/* According to table 21.90 */
static int decode_nr_slots(uint8_t in)
{
const uint8_t dec_tbl[] = {
[0x0] = 0, /* first sub-slot */
[0x1] = 1,
[0x2] = 2,
[0x3] = 3,
[0x4] = 4,
[0x5] = 5,
[0x6] = 6,
[0x7] = 8,
[0x8] = 10,
[0x9] = 13,
[0xa] = 17,
[0xb] = 24,
[0xc] = 34,
[0xd] = 51,
[0xe] = 68,
[0xf] = 0xff /* second sub-slot */
};
return dec_tbl[in & 0xf];
}
/* Section 21.4.3.1 MAC-RESOURCE */
int macpdu_decode_resource(struct tetra_resrc_decoded *rsd, const uint8_t *bits)
{
@ -128,6 +152,7 @@ int macpdu_decode_resource(struct tetra_resrc_decoded *rsd, const uint8_t *bits)
rsd->addr.type = bits_to_uint(cur, 3); cur += 3;
switch (rsd->addr.type) {
case ADDR_TYPE_NULL:
return 0;
break;
case ADDR_TYPE_SSI:
case ADDR_TYPE_USSI:
@ -148,16 +173,26 @@ int macpdu_decode_resource(struct tetra_resrc_decoded *rsd, const uint8_t *bits)
break;
}
cur += addr_len_by_type[rsd->addr.type];
/* no intermediate mapping in pi/4 */
/* no intermediate napping in pi/4 */
rsd->power_control_pres = *cur++;
if (rsd->power_control_pres)
cur += 4;
rsd->slot_granting_pres = *cur++;
if (rsd->slot_granting_pres) {
if (*cur++)
rsd->slot_granting.pres = *cur++;
if (rsd->slot_granting.pres) {
#if 0
/* check for multiple slot granting flag (can only exist in QAM) */
if (*cur++) {
cur += 0; //FIXME;
else
cur += 8;
} else {
#endif
rsd->slot_granting.nr_slots =
decode_nr_slots(bits_to_uint(cur, 4));
cur += 4;
rsd->slot_granting.delay = bits_to_uint(cur, 4);
cur += 4;
#if 0
}
#endif
}
rsd->chan_alloc_pres = *cur++;
/* FIXME: If encryption is enabled, Channel Allocation is encrypted !!! */

6
src/tetra_mac_pdu.h
View File

@ -207,7 +207,11 @@ struct tetra_resrc_decoded {
uint8_t power_control_pres;
uint8_t slot_granting_pres;
struct {
uint8_t nr_slots;
uint8_t delay;
uint8_t pres;
} slot_granting;
uint8_t chan_alloc_pres;
struct tetra_chan_alloc_decoded cad;