[PATCH 7/9] sgsn: Handle different levels of QoS

[Holger Freyther]

From: Holger Hans Peter Freyther <holger at moiji-mobile.com>

If QoS is only three bytes it does not include the allocation/
retention policy. Otherwise it does. Copy it depending on that.
We should have a macro for the clamping to reduce code duplication.

The insanity does come from the MAP data and this seems to be
the easiest in terms of complexity. It is an array of bytes that
is transported from MAPProxy to the SGSN and then simply forwarded.
---
 openbsc/src/gprs/sgsn_libgtp.c | 17 ++++++++++++-----
 1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/openbsc/src/gprs/sgsn_libgtp.c b/openbsc/src/gprs/sgsn_libgtp.c
index dd02457..5c0a0fd 100644
--- a/openbsc/src/gprs/sgsn_libgtp.c
+++ b/openbsc/src/gprs/sgsn_libgtp.c
@@ -199,11 +199,18 @@ struct sgsn_pdp_ctx *sgsn_create_pdp_ctx(struct sgsn_ggsn_ctx *ggsn,
 		qos = TLVP_VAL(tp, OSMO_IE_GSM_REQ_QOS);
 	}
 
-	pdp->qos_req.l = qos_len + 1;
-	if (pdp->qos_req.l > sizeof(pdp->qos_req.v))
-		pdp->qos_req.l = sizeof(pdp->qos_req.v);
-	pdp->qos_req.v[0] = 0; /* Allocation/Retention policy */
-	memcpy(&pdp->qos_req.v[1], qos, pdp->qos_req.l - 1);
+	if (qos_len <= 3) {
+		pdp->qos_req.l = qos_len + 1;
+		if (pdp->qos_req.l > sizeof(pdp->qos_req.v))
+			pdp->qos_req.l = sizeof(pdp->qos_req.v);
+		pdp->qos_req.v[0] = 0; /* Allocation/Retention policy */
+		memcpy(&pdp->qos_req.v[1], qos, pdp->qos_req.l - 1);
+	} else {
+		pdp->qos_req.l = qos_len;
+		if (pdp->qos_req.l > sizeof(pdp->qos_req.v))
+			pdp->qos_req.l = sizeof(pdp->qos_req.v);
+		memcpy(&pdp->qos_req, qos, pdp->qos_req.l);
+	}
 
 	/* SGSN address for control plane */
 	pdp->gsnlc.l = sizeof(sgsn->cfg.gtp_listenaddr.sin_addr);
-- 
2.3.5