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Put rrcSetupRequest/rrcReestablishmentRequest handling in separate functions

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This commit is contained in:
Robert Schmidt
2023-11-08 10:18:52 +01:00
parent 1153e62e45
commit 9a092c1433
1 changed files with 164 additions and 171 deletions
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openair2/RRC/NR/rrc_gNB.c
+164 -171
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@@ -106,7 +106,7 @@
extern RAN_CONTEXT_t RC; extern RAN_CONTEXT_t RC;
static inline uint64_t bitStr_to_uint64(BIT_STRING_t *asn); static inline uint64_t bitStr_to_uint64(const BIT_STRING_t *asn);
mui_t rrc_gNB_mui = 0; mui_t rrc_gNB_mui = 0;
@@ -1153,22 +1153,162 @@ int nr_rrc_reconfiguration_req(rrc_gNB_ue_context_t *const ue_context_pP
return 0; return 0;
} }
/*------------------------------------------------------------------------------*/ static void rrc_handle_RRCSetupRequest(gNB_RRC_INST *rrc, const NR_RRCSetupRequest_IEs_t *rrcSetupRequest, const f1ap_initial_ul_rrc_message_t *msg)
static int nr_rrc_gNB_decode_ccch(module_id_t module_id, const f1ap_initial_ul_rrc_message_t *msg)
{ {
asn_dec_rval_t dec_rval; rrc_gNB_ue_context_t *ue_context_p = NULL;
NR_UL_CCCH_Message_t *ul_ccch_msg = NULL; if (NR_InitialUE_Identity_PR_randomValue == rrcSetupRequest->ue_Identity.present) {
gNB_RRC_INST *gnb_rrc_inst = RC.nrrrc[module_id]; /* randomValue BIT STRING (SIZE (39)) */
NR_RRCSetupRequest_IEs_t *rrcSetupRequest = NULL; if (rrcSetupRequest->ue_Identity.choice.randomValue.size != 5) { // 39-bit random value
NR_RRCReestablishmentRequest_IEs_t rrcReestablishmentRequest; LOG_E(NR_RRC,
rnti_t rnti = msg->crnti; "wrong InitialUE-Identity randomValue size, expected 5, provided %lu",
(long unsigned int)rrcSetupRequest->ue_Identity.choice.randomValue.size);
return;
}
uint64_t random_value = 0;
memcpy(((uint8_t *)&random_value) + 3,
rrcSetupRequest->ue_Identity.choice.randomValue.buf,
rrcSetupRequest->ue_Identity.choice.randomValue.size);
/* if there is already a registered UE (with another RNTI) with this random_value,
* the current one must be removed from MAC/PHY (zombie UE)
*/
if ((ue_context_p = rrc_gNB_ue_context_random_exist(rrc, random_value))) {
LOG_W(NR_RRC, "new UE rnti (coming with random value) is already there, removing UE %x from MAC/PHY\n", msg->crnti);
AssertFatal(false, "not implemented\n");
}
ue_context_p = rrc_gNB_create_ue_context(msg->crnti, rrc, random_value, msg->gNB_DU_ue_id);
} else if (NR_InitialUE_Identity_PR_ng_5G_S_TMSI_Part1 == rrcSetupRequest->ue_Identity.present) {
/* <5G-S-TMSI> = <AMF Set ID><AMF Pointer><5G-TMSI> 48-bit */
/* ng-5G-S-TMSI-Part1 BIT STRING (SIZE (39)) */
if (rrcSetupRequest->ue_Identity.choice.ng_5G_S_TMSI_Part1.size != 5) {
LOG_E(NR_RRC,
"wrong ng_5G_S_TMSI_Part1 size, expected 5, provided %lu \n",
(long unsigned int)rrcSetupRequest->ue_Identity.choice.ng_5G_S_TMSI_Part1.size);
return;
}
uint64_t s_tmsi_part1 = bitStr_to_uint64(&rrcSetupRequest->ue_Identity.choice.ng_5G_S_TMSI_Part1);
// memcpy(((uint8_t *) & random_value) + 3,
// rrcSetupRequest->ue_Identity.choice.ng_5G_S_TMSI_Part1.buf,
// rrcSetupRequest->ue_Identity.choice.ng_5G_S_TMSI_Part1.size);
if ((ue_context_p = rrc_gNB_ue_context_5g_s_tmsi_exist(rrc, s_tmsi_part1))) {
gNB_RRC_UE_t *UE = &ue_context_p->ue_context;
LOG_I(NR_RRC, " 5G-S-TMSI-Part1 exists, old rnti %04x => %04x\n", UE->rnti, msg->crnti);
AssertFatal(false, "not implemented\n");
/* replace rnti in the context */
UE->rnti = msg->crnti;
} else {
LOG_I(NR_RRC, "UE %04x 5G-S-TMSI-Part1 doesn't exist, setting ng_5G_S_TMSI_Part1 => %ld\n", msg->crnti, s_tmsi_part1);
ue_context_p = rrc_gNB_create_ue_context(msg->crnti, rrc, s_tmsi_part1, msg->gNB_DU_ue_id);
AssertFatal(ue_context_p != NULL, "out of memory\n");
gNB_RRC_UE_t *UE = &ue_context_p->ue_context;
UE->Initialue_identity_5g_s_TMSI.presence = true;
UE->ng_5G_S_TMSI_Part1 = s_tmsi_part1;
}
} else {
uint64_t random_value = 0;
memcpy(((uint8_t *)&random_value) + 3,
rrcSetupRequest->ue_Identity.choice.randomValue.buf,
rrcSetupRequest->ue_Identity.choice.randomValue.size);
ue_context_p = rrc_gNB_create_ue_context(msg->crnti, rrc, random_value, msg->gNB_DU_ue_id);
LOG_E(NR_RRC, "RRCSetupRequest without random UE identity or S-TMSI not supported, let's reject the UE %04x\n", msg->crnti);
rrc_gNB_generate_RRCReject(0, ue_context_p);
return;
}
gNB_RRC_UE_t *UE = &ue_context_p->ue_context;
UE = &ue_context_p->ue_context;
UE->establishment_cause = rrcSetupRequest->establishmentCause;
UE->Srb[1].Active = 1;
rrc_gNB_generate_RRCSetup(0, msg->crnti, ue_context_p, msg->du2cu_rrc_container, msg->du2cu_rrc_container_length);
}
static void rrc_handle_RRCReestablishmentRequest(gNB_RRC_INST *rrc, const NR_RRCReestablishmentRequest_IEs_t *req, const f1ap_initial_ul_rrc_message_t *msg)
{
const NR_ReestablishmentCause_t cause = req->reestablishmentCause;
const long physCellId = req->ue_Identity.physCellId;
LOG_I(NR_RRC,
"UE %04x physCellId %ld NR_RRCReestablishmentRequest cause %s\n",
msg->crnti,
physCellId,
cause == NR_ReestablishmentCause_otherFailure
? "Other Failure"
: (cause == NR_ReestablishmentCause_handoverFailure ? "Handover Failure" : "reconfigurationFailure"));
/* look up corresponding DU. For the moment, there is only one */ /* look up corresponding DU. For the moment, there is only one */
const nr_rrc_du_container_t *du = gnb_rrc_inst->du; const nr_rrc_du_container_t *du = rrc->du;
AssertFatal(du != NULL, "received CCCH message, but no corresponding DU found\n"); AssertFatal(du != NULL, "received CCCH message, but no corresponding DU found\n");
AssertFatal(du->setup_req->num_cells_available == 1, "cannot handle more than one cell\n");
const f1ap_served_cell_info_t *cell_info = &du->setup_req->cell[0].info;
if (physCellId != cell_info->nr_pci) {
/* UE was moving from previous cell so quickly that RRCReestablishment for previous cell was received in this cell */
LOG_E(NR_RRC,
" NR_RRCReestablishmentRequest ue_Identity.physCellId(%ld) is not equal to current physCellId(%d), fallback to RRC "
"establishment\n",
physCellId,
cell_info->nr_pci);
/* 38.401 8.7: "If the UE accessed from a gNB-DU other than the
* original one, the gNB-CU should trigger the UE Context Setup
* procedure" we did not implement this yet; TBD for Multi-DU */
AssertFatal(false, "not implemented\n");
return;
}
LOG_I(NR_RRC, "Decoding CCCH: RNTI %04x, payload_size %d\n", rnti, msg->rrc_container_length); rnti_t old_rnti = req->ue_Identity.c_RNTI;
dec_rval = // TODO: we need to check within a specific DU!
rrc_gNB_ue_context_t *ue_context_p = rrc_gNB_get_ue_context_by_rnti(rrc, old_rnti);
gNB_RRC_UE_t *UE = &ue_context_p->ue_context;
/* in case we need to do RRC Setup, give the UE a new random identity */
uint64_t random_value;
fill_random(&random_value, sizeof(random_value));
random_value = random_value & 0x7fffffffff; /* random value is 39 bits */
if (ue_context_p == NULL) {
LOG_E(NR_RRC, "NR_RRCReestablishmentRequest without UE context, fallback to RRC setup\n");
ue_context_p = rrc_gNB_create_ue_context(msg->crnti, rrc, random_value, msg->gNB_DU_ue_id);
ue_context_p->ue_context.Srb[1].Active = 1;
rrc_gNB_generate_RRCSetup(0, msg->crnti, ue_context_p, msg->du2cu_rrc_container, msg->du2cu_rrc_container_length);
return;
}
// 3GPP TS 38.321 version 15.13.0 Section 7.1 Table 7.1-1: RNTI values
if (req->ue_Identity.c_RNTI < 0x1 || req->ue_Identity.c_RNTI > 0xffef) {
/* c_RNTI range error should not happen */
LOG_E(NR_RRC,
"NR_RRCReestablishmentRequest c_RNTI %04lx range error, fallback to RRC setup\n",
req->ue_Identity.c_RNTI);
ue_context_p = rrc_gNB_create_ue_context(msg->crnti, rrc, random_value, msg->gNB_DU_ue_id);
ue_context_p->ue_context.Srb[1].Active = 1;
rrc_gNB_generate_RRCSetup(0, msg->crnti, ue_context_p, msg->du2cu_rrc_container, msg->du2cu_rrc_container_length);
return;
}
/* TODO: start timer in ITTI and drop UE if it does not come back */
// update with new RNTI, and update secondary UE association
UE->rnti = msg->crnti;
cu_remove_f1_ue_data(UE->rrc_ue_id);
f1_ue_data_t ue_data = {.secondary_ue = msg->crnti};
cu_add_f1_ue_data(UE->rrc_ue_id, &ue_data);
UE->reestablishment_cause = cause;
LOG_D(NR_RRC, "Accept req-> UE physCellId %ld cause %ld\n", physCellId, cause);
rrc_gNB_generate_RRCReestablishment(ue_context_p, msg->du2cu_rrc_container, old_rnti, du);
}
static int nr_rrc_gNB_decode_ccch(module_id_t module_id, const f1ap_initial_ul_rrc_message_t *msg)
{
gNB_RRC_INST *rrc = RC.nrrrc[module_id];
LOG_I(NR_RRC, "Decoding CCCH: RNTI %04x, payload_size %d\n", msg->crnti, msg->rrc_container_length);
NR_UL_CCCH_Message_t *ul_ccch_msg = NULL;
asn_dec_rval_t dec_rval =
uper_decode(NULL, &asn_DEF_NR_UL_CCCH_Message, (void **)&ul_ccch_msg, msg->rrc_container, msg->rrc_container_length, 0, 0); uper_decode(NULL, &asn_DEF_NR_UL_CCCH_Message, (void **)&ul_ccch_msg, msg->rrc_container, msg->rrc_container_length, 0, 0);
if (dec_rval.code != RC_OK || dec_rval.consumed == 0) { if (dec_rval.code != RC_OK || dec_rval.consumed == 0) {
@@ -1179,180 +1319,33 @@ static int nr_rrc_gNB_decode_ccch(module_id_t module_id, const f1ap_initial_ul_r
if (ul_ccch_msg->message.present == NR_UL_CCCH_MessageType_PR_c1) { if (ul_ccch_msg->message.present == NR_UL_CCCH_MessageType_PR_c1) {
switch (ul_ccch_msg->message.choice.c1->present) { switch (ul_ccch_msg->message.choice.c1->present) {
case NR_UL_CCCH_MessageType__c1_PR_NOTHING: case NR_UL_CCCH_MessageType__c1_PR_NOTHING:
/* TODO */ LOG_W(NR_RRC, "Received PR_NOTHING on UL-CCCH-Message, ignoring message\n");
LOG_I(NR_RRC, "Received PR_NOTHING on UL-CCCH-Message\n");
break; break;
case NR_UL_CCCH_MessageType__c1_PR_rrcSetupRequest: case NR_UL_CCCH_MessageType__c1_PR_rrcSetupRequest:
LOG_D(NR_RRC, "Received RRCSetupRequest on UL-CCCH-Message (UE rnti %04x)\n", rnti); LOG_D(NR_RRC, "Received RRCSetupRequest on UL-CCCH-Message (UE rnti %04x)\n", msg->crnti);
{ rrc_handle_RRCSetupRequest(rrc, &ul_ccch_msg->message.choice.c1->choice.rrcSetupRequest->rrcSetupRequest, msg);
rrcSetupRequest = &ul_ccch_msg->message.choice.c1->choice.rrcSetupRequest->rrcSetupRequest;
rrc_gNB_ue_context_t *ue_context_p = NULL;
if (NR_InitialUE_Identity_PR_randomValue == rrcSetupRequest->ue_Identity.present) {
/* randomValue BIT STRING (SIZE (39)) */
if (rrcSetupRequest->ue_Identity.choice.randomValue.size != 5) { // 39-bit random value
LOG_E(NR_RRC, "wrong InitialUE-Identity randomValue size, expected 5, provided %lu", (long unsigned int)rrcSetupRequest->ue_Identity.choice.randomValue.size);
ASN_STRUCT_FREE(asn_DEF_NR_UL_CCCH_Message, ul_ccch_msg);
return -1;
}
uint64_t random_value = 0;
memcpy(((uint8_t *)&random_value) + 3, rrcSetupRequest->ue_Identity.choice.randomValue.buf, rrcSetupRequest->ue_Identity.choice.randomValue.size);
/* if there is already a registered UE (with another RNTI) with this random_value,
* the current one must be removed from MAC/PHY (zombie UE)
*/
if ((ue_context_p = rrc_gNB_ue_context_random_exist(gnb_rrc_inst, random_value))) {
LOG_W(NR_RRC, "new UE rnti (coming with random value) is already there, removing UE %x from MAC/PHY\n", rnti);
AssertFatal(false, "not implemented\n");
}
ue_context_p = rrc_gNB_create_ue_context(rnti, gnb_rrc_inst, random_value, msg->gNB_DU_ue_id);
} else if (NR_InitialUE_Identity_PR_ng_5G_S_TMSI_Part1 == rrcSetupRequest->ue_Identity.present) {
/* TODO */
/* <5G-S-TMSI> = <AMF Set ID><AMF Pointer><5G-TMSI> 48-bit */
/* ng-5G-S-TMSI-Part1 BIT STRING (SIZE (39)) */
if (rrcSetupRequest->ue_Identity.choice.ng_5G_S_TMSI_Part1.size != 5) {
LOG_E(NR_RRC, "wrong ng_5G_S_TMSI_Part1 size, expected 5, provided %lu \n", (long unsigned int)rrcSetupRequest->ue_Identity.choice.ng_5G_S_TMSI_Part1.size);
ASN_STRUCT_FREE(asn_DEF_NR_UL_CCCH_Message, ul_ccch_msg);
return -1;
}
uint64_t s_tmsi_part1 = bitStr_to_uint64(&rrcSetupRequest->ue_Identity.choice.ng_5G_S_TMSI_Part1);
// memcpy(((uint8_t *) & random_value) + 3,
// rrcSetupRequest->ue_Identity.choice.ng_5G_S_TMSI_Part1.buf,
// rrcSetupRequest->ue_Identity.choice.ng_5G_S_TMSI_Part1.size);
if ((ue_context_p = rrc_gNB_ue_context_5g_s_tmsi_exist(gnb_rrc_inst, s_tmsi_part1))) {
gNB_RRC_UE_t *UE = &ue_context_p->ue_context;
LOG_I(NR_RRC, " 5G-S-TMSI-Part1 exists, old rnti %04x => %04x\n", UE->rnti, rnti);
AssertFatal(false, "not implemented\n");
/* replace rnti in the context */
UE->rnti = rnti;
} else {
LOG_I(NR_RRC, "UE %04x 5G-S-TMSI-Part1 doesn't exist, setting ng_5G_S_TMSI_Part1 => %ld\n", rnti, s_tmsi_part1);
ue_context_p = rrc_gNB_create_ue_context(rnti, gnb_rrc_inst, s_tmsi_part1, msg->gNB_DU_ue_id);
AssertFatal(ue_context_p != NULL, "out of memory\n");
gNB_RRC_UE_t *UE = &ue_context_p->ue_context;
UE->Initialue_identity_5g_s_TMSI.presence = true;
UE->ng_5G_S_TMSI_Part1 = s_tmsi_part1;
}
} else {
/* TODO */
uint64_t random_value = 0;
memcpy(((uint8_t *)&random_value) + 3, rrcSetupRequest->ue_Identity.choice.randomValue.buf, rrcSetupRequest->ue_Identity.choice.randomValue.size);
ue_context_p = rrc_gNB_create_ue_context(rnti, gnb_rrc_inst, random_value, msg->gNB_DU_ue_id);
LOG_E(NR_RRC, "RRCSetupRequest without random UE identity or S-TMSI not supported, let's reject the UE %04x\n", rnti);
rrc_gNB_generate_RRCReject(module_id, ue_context_p);
break;
}
gNB_RRC_UE_t *UE = &ue_context_p->ue_context;
UE = &ue_context_p->ue_context;
UE->establishment_cause = rrcSetupRequest->establishmentCause;
UE->Srb[1].Active = 1;
rrc_gNB_generate_RRCSetup(module_id,
rnti,
ue_context_p,
msg->du2cu_rrc_container,
msg->du2cu_rrc_container_length);
}
break; break;
case NR_UL_CCCH_MessageType__c1_PR_rrcResumeRequest: case NR_UL_CCCH_MessageType__c1_PR_rrcResumeRequest:
LOG_I(NR_RRC, "receive rrcResumeRequest message \n"); LOG_E(NR_RRC, "Received rrcResumeRequest message, but handling is not implemented\n");
break; break;
case NR_UL_CCCH_MessageType__c1_PR_rrcReestablishmentRequest: { case NR_UL_CCCH_MessageType__c1_PR_rrcReestablishmentRequest: {
LOG_DUMPMSG(NR_RRC, LOG_D(NR_RRC, "Received RRCReestablishmentRequest on UL-CCCH-Message (UE RNTI %04x)\n", msg->crnti);
DEBUG_RRC, rrc_handle_RRCReestablishmentRequest(
(char *)(msg->rrc_container), rrc,
msg->rrc_container_length, &ul_ccch_msg->message.choice.c1->choice.rrcReestablishmentRequest->rrcReestablishmentRequest,
"[MSG] RRC Reestablishment Request\n"); msg);
rrcReestablishmentRequest = ul_ccch_msg->message.choice.c1->choice.rrcReestablishmentRequest->rrcReestablishmentRequest;
const NR_ReestablishmentCause_t cause = rrcReestablishmentRequest.reestablishmentCause;
const long physCellId = rrcReestablishmentRequest.ue_Identity.physCellId;
LOG_I(NR_RRC,
"UE %04x physCellId %ld NR_RRCReestablishmentRequest cause %s\n",
rnti,
physCellId,
cause == NR_ReestablishmentCause_otherFailure
? "Other Failure"
: (cause == NR_ReestablishmentCause_handoverFailure ? "Handover Failure" : "reconfigurationFailure"));
AssertFatal(du->setup_req->num_cells_available == 1, "cannot handle more than one cell\n");
const f1ap_served_cell_info_t *cell_info = &du->setup_req->cell[0].info;
if (physCellId != cell_info->nr_pci) {
/* UE was moving from previous cell so quickly that RRCReestablishment for previous cell was received in this cell */
LOG_E(NR_RRC,
" NR_RRCReestablishmentRequest ue_Identity.physCellId(%ld) is not equal to current physCellId(%d), fallback to RRC establishment\n",
physCellId,
cell_info->nr_pci);
/* 38.401 8.7: "If the UE accessed from a gNB-DU other than the
* original one, the gNB-CU should trigger the UE Context Setup
* procedure" we did not implement this yet; TBD for Multi-DU */
AssertFatal(false, "not implemented\n");
break;
}
for (int i = 0; i < rrcReestablishmentRequest.ue_Identity.shortMAC_I.size; i++) {
LOG_D(NR_RRC, "rrcReestablishmentRequest.ue_Identity.shortMAC_I.buf[%d] = %x\n", i, rrcReestablishmentRequest.ue_Identity.shortMAC_I.buf[i]);
}
rnti_t old_rnti = rrcReestablishmentRequest.ue_Identity.c_RNTI;
// TODO: we need to check within a specific DU!
rrc_gNB_ue_context_t *ue_context_p = rrc_gNB_get_ue_context_by_rnti(gnb_rrc_inst, old_rnti);
gNB_RRC_UE_t *UE = &ue_context_p->ue_context;
/* in case we need to do RRC Setup, give the UE a new random identity */
uint64_t random_value;
fill_random(&random_value, sizeof(random_value));
random_value = random_value & 0x7fffffffff; /* random value is 39 bits */
if (ue_context_p == NULL) {
LOG_E(NR_RRC, "NR_RRCReestablishmentRequest without UE context, fallback to RRC setup\n");
ue_context_p = rrc_gNB_create_ue_context(rnti, gnb_rrc_inst, random_value, msg->gNB_DU_ue_id);
ue_context_p->ue_context.Srb[1].Active = 1;
rrc_gNB_generate_RRCSetup(module_id, rnti, ue_context_p, msg->du2cu_rrc_container, msg->du2cu_rrc_container_length);
break;
}
// 3GPP TS 38.321 version 15.13.0 Section 7.1 Table 7.1-1: RNTI values
if (rrcReestablishmentRequest.ue_Identity.c_RNTI < 0x1 || rrcReestablishmentRequest.ue_Identity.c_RNTI > 0xffef) {
/* c_RNTI range error should not happen */
LOG_E(NR_RRC,
"NR_RRCReestablishmentRequest c_RNTI %04lx range error, fallback to RRC setup\n",
rrcReestablishmentRequest.ue_Identity.c_RNTI);
ue_context_p = rrc_gNB_create_ue_context(rnti, gnb_rrc_inst, random_value, msg->gNB_DU_ue_id);
ue_context_p->ue_context.Srb[1].Active = 1;
rrc_gNB_generate_RRCSetup(module_id, rnti, ue_context_p, msg->du2cu_rrc_container, msg->du2cu_rrc_container_length);
break;
}
/* TODO: start timer in ITTI and drop UE if it does not come back */
// update with new RNTI, and update secondary UE association
UE->rnti = rnti;
cu_remove_f1_ue_data(UE->rrc_ue_id);
f1_ue_data_t ue_data = {.secondary_ue = rnti};
cu_add_f1_ue_data(UE->rrc_ue_id, &ue_data);
UE->reestablishment_cause = cause;
LOG_D(NR_RRC, "Accept RRCReestablishmentRequest from UE physCellId %ld cause %ld\n", physCellId, cause);
rrc_gNB_generate_RRCReestablishment(ue_context_p,
msg->du2cu_rrc_container,
old_rnti,
du);
} break; } break;
case NR_UL_CCCH_MessageType__c1_PR_rrcSystemInfoRequest: case NR_UL_CCCH_MessageType__c1_PR_rrcSystemInfoRequest:
LOG_I(NR_RRC, "UE %04x receive rrcSystemInfoRequest message \n", rnti); LOG_I(NR_RRC, "UE %04x receive rrcSystemInfoRequest message \n", msg->crnti);
/* TODO */ /* TODO */
break; break;
default: default:
LOG_E(NR_RRC, "UE %04x Unknown message\n", rnti); LOG_E(NR_RRC, "UE %04x Unknown message\n", msg->crnti);
break; break;
} }
} }
@@ -1365,7 +1358,7 @@ static int nr_rrc_gNB_decode_ccch(module_id_t module_id, const f1ap_initial_ul_r
*\param[in] pointer to the BIT_STRING_t object. *\param[in] pointer to the BIT_STRING_t object.
*\return the extracted value. *\return the extracted value.
*/ */
static inline uint64_t bitStr_to_uint64(BIT_STRING_t *asn) { static inline uint64_t bitStr_to_uint64(const BIT_STRING_t *asn) {
uint64_t result = 0; uint64_t result = 0;
int index; int index;
int shift; int shift;