[gprs] gb-proxy: We might receive a NS-RESET for a NS-VC that we already know
In this case, don't blindly allocate a new NS-VC but rather use the NSEI
to lookup the 'struct gprs_nsvc' for it.
diff --git a/openbsc/src/gprs/gprs_ns.c b/openbsc/src/gprs/gprs_ns.c
index bd9791a..3d05dd0 100644
--- a/openbsc/src/gprs/gprs_ns.c
+++ b/openbsc/src/gprs/gprs_ns.c
@@ -483,6 +483,8 @@
/* look up the NSVC based on source address */
nsvc = nsvc_by_rem_addr(nsi, saddr);
if (!nsvc) {
+ struct tlv_parsed tp;
+ uint16_t nsei;
/* Only the RESET procedure creates a new NSVC */
if (nsh->pdu_type != NS_PDUT_RESET) {
LOGP(DNS, LOGL_INFO, "Ignoring NS PDU type 0x%0x "
@@ -491,10 +493,25 @@
//gprs_ns_tx_reset(nsvc, NS_CAUSE_NSVC_UNKNOWN);
return -EIO;
}
- LOGP(DNS, LOGL_INFO, "Creating NS-VC for BSS at %s:%u\n",
- inet_ntoa(saddr->sin_addr), ntohs(saddr->sin_port));
- nsvc = nsvc_create(nsi, 0xffff);
- nsvc->ip.bts_addr = *saddr;
+ rc = tlv_parse(&tp, &ns_att_tlvdef, nsh->data,
+ msgb_l2len(msg), 0, 0);
+ if (!TLVP_PRESENT(&tp, NS_IE_CAUSE) ||
+ !TLVP_PRESENT(&tp, NS_IE_VCI) ||
+ !TLVP_PRESENT(&tp, NS_IE_NSEI)) {
+ /* FIXME: respond with NS_CAUSE_MISSING_ESSENT_IE */
+ LOGP(DNS, LOGL_ERROR, "NS RESET Missing mandatory IE\n");
+ return -EINVAL;
+ }
+ nsei = ntohs(*(uint16_t *)TLVP_VAL(&tp, NS_IE_NSEI));
+ /* Check if we already know this NSEI, the remote end might
+ * simply have changed addresses, or it is a SGSN */
+ nsvc = nsvc_by_nsei(nsi, nsei);
+ if (!nsvc) {
+ LOGP(DNS, LOGL_INFO, "Creating NS-VC for BSS at %s:%u\n",
+ inet_ntoa(saddr->sin_addr), ntohs(saddr->sin_port));
+ nsvc = nsvc_create(nsi, 0xffff);
+ nsvc->ip.bts_addr = *saddr;
+ }
} else
msgb_nsei(msg) = nsvc->nsei;