laforge has submitted this change. ( https://gerrit.osmocom.org/c/osmo-hnbgw/+/36477?usp=email )

Change subject: HNBAP: Always respond to UE-REGISTER-REQUEST ......................................................................

HNBAP: Always respond to UE-REGISTER-REQUEST

We always should respond to a UE-REGISTER-REQ. Either it's an ACK or we must send a REJ. There should not be any "quiet" error cases where we don't respond at all:

* send general Error Indication at a point where we cannot decode the UE-Identity-IE (which is mandatory in UE-REGISTER-REJECT) * send UE-REGISTER-REJECT with matching cause value whenever we have the decoded UE Identity around

Change-Id: I5338a1324545b2c6d31fb45f1e69fee45842e207 --- M src/osmo-hnbgw/hnbgw_hnbap.c 1 file changed, 73 insertions(+), 9 deletions(-)

Approvals: Jenkins Builder: Verified laforge: Looks good to me, approved pespin: Looks good to me, but someone else must approve

diff --git a/src/osmo-hnbgw/hnbgw_hnbap.c b/src/osmo-hnbgw/hnbgw_hnbap.c index 9ffb0ba..631c782 100644 --- a/src/osmo-hnbgw/hnbgw_hnbap.c +++ b/src/osmo-hnbgw/hnbgw_hnbap.c @@ -49,6 +49,48 @@ return 0; }

+static int hnbgw_tx_error_ind(struct hnb_context *ctx, const HNBAP_Cause_t *cause, + HNBAP_ProcedureCode_t proc_code, HNBAP_Criticality_t criticality, + HNBAP_TriggeringMessage_t trig_msg) +{ + HNBAP_ErrorIndication_t err_ind; + HNBAP_ErrorIndicationIEs_t err_ind_ies; + struct msgb *msg; + int rc; + + LOGHNB(ctx, DHNBAP, LOGL_ERROR, "Tx ErrorIndication cause=%s\n", hnbap_cause_str(cause)); + + err_ind_ies.presenceMask = 0; + err_ind_ies.cause = *cause; + + if (proc_code != -1 || trig_msg != -1 || criticality != -1) { + err_ind_ies.presenceMask |= ERRORINDICATIONIES_HNBAP_CRITICALITYDIAGNOSTICS_PRESENT; + if (proc_code != -1) + err_ind_ies.criticalityDiagnostics.procedureCode = &proc_code; + if (trig_msg != -1) + err_ind_ies.criticalityDiagnostics.triggeringMessage = &trig_msg; + if (criticality != -1) + err_ind_ies.criticalityDiagnostics.procedureCriticality = &criticality; + } + + memset(&err_ind, 0, sizeof(err_ind)); + rc = hnbap_encode_errorindicationies(&err_ind, &err_ind_ies); + if (rc < 0) { + LOGHNB(ctx, DHNBAP, LOGL_ERROR, "Failure to encode ERROR-INDICATION to %s: rc=%d\n", + ctx->identity_info, rc); + return rc; + } + + msg = hnbap_generate_initiating_message(HNBAP_ProcedureCode_id_ErrorIndication, + HNBAP_Criticality_ignore, + &asn_DEF_HNBAP_ErrorIndication, + &err_ind); + + ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_HNBAP_ErrorIndication, &err_ind); + + return hnbgw_hnbap_tx(ctx, msg); +} + static int hnbgw_tx_hnb_register_rej(struct hnb_context *ctx, const HNBAP_Cause_t *cause) { HNBAP_HNBRegisterReject_t reject_out; @@ -514,14 +556,20 @@ static int hnbgw_rx_ue_register_req(struct hnb_context *ctx, ANY_t *in) { HNBAP_UERegisterRequestIEs_t ies; + HNBAP_Cause_t cause; struct ue_context *ue; struct ue_context *ue_allocated = NULL; char imsi[16]; int rc;

rc = hnbap_decode_ueregisterrequesties(&ies, in); - if (rc < 0) - return rc; + if (rc < 0) { + LOGHNB(ctx, DHNBAP, LOGL_ERROR, "Failure to decode UE-REGISTER-REQ: rc=%d\n", rc); + cause.present = HNBAP_Cause_PR_protocol; + cause.choice.radioNetwork = HNBAP_CauseProtocol_unspecified; + return hnbgw_tx_error_ind(ctx, &cause, HNBAP_ProcedureCode_id_UERegister, HNBAP_Criticality_reject, + HNBAP_TriggeringMessage_initiating_message); + }

switch (ies.uE_Identity.present) { case HNBAP_UE_Identity_PR_iMSI: @@ -541,12 +589,8 @@ if (g_hnbgw->config.hnbap_allow_tmsi) { rc = hnbgw_tx_ue_register_acc_tmsi(ctx, &ies.uE_Identity); } else { - struct HNBAP_Cause cause = { - .present = HNBAP_Cause_PR_radioNetwork, - .choice = { - .radioNetwork = HNBAP_CauseRadioNetwork_invalid_UE_identity, - }, - }; + cause.present = HNBAP_Cause_PR_radioNetwork; + cause.choice.radioNetwork = HNBAP_CauseRadioNetwork_invalid_UE_identity; rc = hnbgw_tx_ue_register_rej(ctx, &ies.uE_Identity, &cause); } /* all has been handled by TMSI, skip the IMSI code below */ @@ -554,7 +598,9 @@ default: LOGHNB(ctx, DHNBAP, LOGL_NOTICE, "UE-REGISTER-REQ with unsupported UE Id type %d\n", ies.uE_Identity.present); - rc = -ENOTSUP; + cause.present = HNBAP_Cause_PR_radioNetwork; + cause.choice.radioNetwork = HNBAP_CauseRadioNetwork_invalid_UE_identity; + rc = hnbgw_tx_ue_register_rej(ctx, &ies.uE_Identity, &cause); goto free_and_return_rc; }