Change in osmo-sgsn[master]: Echo zero byte XID-Field of Type L3_PAR

[Harald Welte]

Harald Welte has submitted this change and it was merged. ( https://gerrit.osmocom.org/13811 )

Change subject: Echo zero byte XID-Field of Type L3_PAR
......................................................................

Echo zero byte XID-Field of Type L3_PAR

After Activate PDP Context request, Motorola KRZR
sends a zero length XID-Field of Type L3 Parameters

If this is not echoed back, the phone will send
Deactivate PDP Context request with SM Cause:
LLC or SNDCP failure(A/Gb only) (25)

Closes: OS#3426

Change-Id: Ibd75f7b943c84ed7264481fa2e4bc3cb2f6745d4
---
M src/gprs/gprs_sndcp.c
1 file changed, 8 insertions(+), 0 deletions(-)

Approvals:
  Harald Welte: Looks good to me, approved; Verified
  Keith Whyte: Looks good to me, but someone else must approve
  Jenkins Builder: Verified



diff --git a/src/gprs/gprs_sndcp.c b/src/gprs/gprs_sndcp.c
index 23d1e9a..d9aa1e5 100644
--- a/src/gprs/gprs_sndcp.c
+++ b/src/gprs/gprs_sndcp.c
@@ -1120,6 +1120,14 @@
 	OSMO_ASSERT(xid_field_response);
 	OSMO_ASSERT(lle);
 
+	/* Some phones send zero byte length SNDCP frames
+	 * and do require a confirmation response. */
+	if (xid_field_indication->data_len == 0) {
+		xid_field_response->type = GPRS_LLC_XID_T_L3_PAR;
+		xid_field_response->data_len = 0;
+		return 0;
+	}
+
 	/* Parse SNDCP-CID XID-Field */
 	comp_fields = gprs_sndcp_parse_xid(&version, lle->llme,
 					   xid_field_indication->data,

-- 
To view, visit https://gerrit.osmocom.org/13811
To unsubscribe, or for help writing mail filters, visit https://gerrit.osmocom.org/settings

Gerrit-Project: osmo-sgsn
Gerrit-Branch: master
Gerrit-MessageType: merged
Gerrit-Change-Id: Ibd75f7b943c84ed7264481fa2e4bc3cb2f6745d4
Gerrit-Change-Number: 13811
Gerrit-PatchSet: 8
Gerrit-Owner: Keith Whyte <keith at rhizomatica.org>
Gerrit-Reviewer: Harald Welte <laforge at gnumonks.org>
Gerrit-Reviewer: Jenkins Builder (1000002)
Gerrit-Reviewer: Keith Whyte <keith at rhizomatica.org>
Gerrit-Reviewer: lynxis lazus <lynxis at fe80.eu>
Gerrit-CC: Pau Espin Pedrol <pespin at sysmocom.de>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osmocom.org/pipermail/gerrit-log/attachments/20190502/34a05a28/attachment.htm>