sgsn_iu: Parse the RAB assignemnt response and get pdp ctx form it

The RAB assignment response includes the gtp teid that we sent along in
the assignment request. Retrieve the correct pdp context from there and
activate it.

1 files changed, 26 insertions, 9 deletions

diff --git a/openbsc/src/gprs/sgsn_iu.c b/openbsc/src/gprs/sgsn_iu.c
index d43111a8b..dee63855d 100644
--- a/openbsc/src/gprs/sgsn_iu.c
+++ b/openbsc/src/gprs/sgsn_iu.c
@@ -32,7 +32,6 @@ struct ue_conn_ctx {
 	struct llist_head list;
 	struct osmo_sua_link *link;
 	uint32_t conn_id;
-	struct sgsn_pdp_ctx *pdp;
 };
 
 static LLIST_HEAD(conn_ctx_list);
@@ -72,8 +71,6 @@ int gprs_iu_rab_act(struct sgsn_pdp_ctx *pdp)
 	uint32_t ggsn_ip;
 
 	uectx = mm->iu.ue_ctx;
-	uectx->pdp = pdp;
-
 
 	/* Get the IP address for ggsn user plane */
 	memcpy(&ggsn_ip, pdp->lib->gsnru.v, pdp->lib->gsnru.l);
@@ -232,24 +229,44 @@ int send_act_pdp_cont_acc(struct sgsn_pdp_ctx *pctx);
 
 static int ranap_handle_co_rab_ass_resp(struct ue_conn_ctx *ctx, RANAP_RAB_AssignmentResponseIEs_t *ies)
 {
+	struct sgsn_mm_ctx *mm;
+	struct sgsn_pdp_ctx *pdp = NULL;
 	int i, rc;
+	uint8_t rab_id;
+	uint32_t gtp_tei;
+
+	mm = sgsn_mm_ctx_by_ue_ctx(ctx);
+	/* XXX: Error handling */
 
 	LOGP(DRANAP, LOGL_INFO, "RAB Asignment Response:");
-	if (0) {
-//	if (ies->presenceMask & RAB_ASSIGNMENTRESPONSEIES_RANAP_RAB_SETUPORMODIFIEDLIST_PRESENT) {
+	if (ies->presenceMask & RAB_ASSIGNMENTRESPONSEIES_RANAP_RAB_SETUPORMODIFIEDLIST_PRESENT) {
+		RANAP_IE_t *ranap_ie = ies->raB_SetupOrModifiedList.raB_SetupOrModifiedList_ies.list.array[0];
 		RANAP_RAB_SetupOrModifiedItemIEs_t setup_ies;
 		RANAP_RAB_SetupOrModifiedItem_t *item = &setup_ies.raB_SetupOrModifiedItem;
-		rc = ranap_decode_rab_setupormodifieditemies(&setup_ies, &ies->raB_SetupOrModifiedList);
+		rc = ranap_decode_rab_setupormodifieditemies(&setup_ies, &ranap_ie->value);
+
+		rab_id = item->rAB_ID.buf[0];
+		if (item->iuTransportAssociation->present == RANAP_IuTransportAssociation_PR_gTP_TEI) {
+			gtp_tei = asn1str_to_u32(&item->iuTransportAssociation->choice.gTP_TEI);
+			pdp = sgsn_pdp_ctx_by_tei(mm, gtp_tei);
+		}
+
+		if (!pdp) {
+			ranap_free_rab_setupormodifieditemies(&setup_ies);
+			return -1;
+		}
+
 		if (item->transportLayerAddress) {
-			uint8_t rab_id = item->rAB_ID.buf[0];
-			LOGPC(DRANAP, LOGL_INFO, " Setup: (%u/%s)", osmo_hexdump(item->transportLayerAddress->buf,
+
+			LOGPC(DRANAP, LOGL_INFO, " Setup: (%u/%s)", rab_id, osmo_hexdump(item->transportLayerAddress->buf,
 									     item->transportLayerAddress->size));
 		}
+		ranap_free_rab_setupormodifieditemies(&setup_ies);
 	}
 
 	LOGPC(DRANAP, LOGL_INFO, "\n");
 
-	send_act_pdp_cont_acc(ctx->pdp);
+	send_act_pdp_cont_acc(pdp);
 
 	return rc;
 }