https://projects.osmocom.org/https://projects.osmocom.org/favicon.ico?16647414092018-08-30T17:55:12ZOpen Source Mobile CommunicationsOsmoSGSN - Bug #3426: gprs_llc_process_xid_ind() does not echo L3_PAR, breaks PDP activation for Motorola KRZRhttps://projects.osmocom.org/issues/3426?journal_id=110862018-08-30T17:55:12Zlaforge
<ul></ul><p>I purchased a KRZR 3 for the sysmocom lab. Not sure when somebody will be able to try to reproduce, but at least we should be able to do now.</p> OsmoSGSN - Bug #3426: gprs_llc_process_xid_ind() does not echo L3_PAR, breaks PDP activation for Motorola KRZRhttps://projects.osmocom.org/issues/3426?journal_id=112742018-09-12T08:33:38Zkeith
<ul></ul><p>I've been running SGSN now for some weeks with this patch in place to allow the KRZR to attach and I have not seen any related problems. (with any other phone)</p> OsmoSGSN - Bug #3426: gprs_llc_process_xid_ind() does not echo L3_PAR, breaks PDP activation for Motorola KRZRhttps://projects.osmocom.org/issues/3426?journal_id=112752018-09-12T08:53:55Zkeith
<ul></ul><p>TS 04.06 [EDIT correction TS 04.64 6.4.1.6 ] is kind of confusing here.</p>
<p>On the one had it says:<br /><em>As an optimisation, parameters confirming the requested values may be omitted from the XID response.</em></p>
<p>also:</p>
<p><em>The responding side may respond with parameters that were not included in the XID command. A parameter that was <br />not included in the XID command shall in this case be treated as if the current value of the parameter was included in <br />the XID command. The <strong>responding side shall include such a parameter in every XID response until the parameter has <br />been explicitly negotiated</strong>, either by responding to an XID command that included the parameter, or by explicitly <br />including the parameter the next time an XID command is transmitted.</em></p>
<p>also:</p>
<p><em>Negotiated XID parameters shall apply to the LLE identified by the DLCI of the XID frames used, except Version, <br />Reset, and IOV-UI that applies to an LLME (i.e., a TLLI), and <strong>except Layer-3 Parameters that apply to the layer 3 <br />above the LLE</strong>.</em></p>
<p>So from that I understand that while we may not actually be applying this L3 param to the LLE identified by the DLCI (to be honest, I haven't even looked up what the dlci is), we still MUST include it in the response.</p>
<p>Maybe this is a mis understanding that is the origin of this <br /><pre>
if (xid_field->type != GPRS_LLC_XID_T_L3_PAR)
</pre></p>
<p>in the code?</p>
<p>Ref: <a class="external" href="https://www.etsi.org/deliver/etsi_ts/101300_101399/101351/08.07.00_60/ts_101351v080700p.pdf#page=29">https://www.etsi.org/deliver/etsi_ts/101300_101399/101351/08.07.00_60/ts_101351v080700p.pdf#page=29</a></p> OsmoSGSN - Bug #3426: gprs_llc_process_xid_ind() does not echo L3_PAR, breaks PDP activation for Motorola KRZRhttps://projects.osmocom.org/issues/3426?journal_id=141582019-04-29T13:02:32Zkeith
<ul><li><strong>Assignee</strong> set to <i>dexter</i></li></ul> OsmoSGSN - Bug #3426: gprs_llc_process_xid_ind() does not echo L3_PAR, breaks PDP activation for Motorola KRZRhttps://projects.osmocom.org/issues/3426?journal_id=141592019-04-29T13:03:11Zkeith
<ul></ul><p>note to self: attach patch and .pcap</p> OsmoSGSN - Bug #3426: gprs_llc_process_xid_ind() does not echo L3_PAR, breaks PDP activation for Motorola KRZRhttps://projects.osmocom.org/issues/3426?journal_id=141602019-04-29T13:16:44Zlaforge
<ul></ul><p>The point is that the L3 parameters are handled in SNDCP, and not in LLC. So the LLC code is correct to only handle the non-L3. The behavioral difference (and possible bug) hence is in the SNDCP XID handling.</p>
<p>What we need is a pcap file showing request and response for both the modified and the unmodified code.</p> OsmoSGSN - Bug #3426: gprs_llc_process_xid_ind() does not echo L3_PAR, breaks PDP activation for Motorola KRZRhttps://projects.osmocom.org/issues/3426?journal_id=141612019-04-29T13:17:54Zlaforge
<ul></ul> OsmoSGSN - Bug #3426: gprs_llc_process_xid_ind() does not echo L3_PAR, breaks PDP activation for Motorola KRZRhttps://projects.osmocom.org/issues/3426?journal_id=141622019-04-29T13:22:47Zlynxis
<ul></ul><p>The interesting function might be the sndcp_sn_xid_ind() in the sgsn.</p> OsmoSGSN - Bug #3426: gprs_llc_process_xid_ind() does not echo L3_PAR, breaks PDP activation for Motorola KRZRhttps://projects.osmocom.org/issues/3426?journal_id=141672019-04-29T17:44:37Zkeith
<ul><li><strong>File</strong> <a href="/attachments/3676">krzr_llc.pre_patch.pcap</a> <a class="icon-only icon-download" title="Download" href="/attachments/download/3676/krzr_llc.pre_patch.pcap">krzr_llc.pre_patch.pcap</a> added</li><li><strong>File</strong> <a href="/attachments/3677">krzr_llc.post_patch.pcap</a> <a class="icon-only icon-download" title="Download" href="/attachments/download/3677/krzr_llc.post_patch.pcap">krzr_llc.post_patch.pcap</a> added</li></ul><p>Posted <a class="external" href="https://gerrit.osmocom.org/#/c/osmo-sgsn/+/13811/">https://gerrit.osmocom.org/#/c/osmo-sgsn/+/13811/</a> for review.</p> OsmoSGSN - Bug #3426: gprs_llc_process_xid_ind() does not echo L3_PAR, breaks PDP activation for Motorola KRZRhttps://projects.osmocom.org/issues/3426?journal_id=141732019-04-30T08:11:25Zkeith
<ul><li><strong>Assignee</strong> changed from <i>dexter</i> to <i>keith</i></li></ul> OsmoSGSN - Bug #3426: gprs_llc_process_xid_ind() does not echo L3_PAR, breaks PDP activation for Motorola KRZRhttps://projects.osmocom.org/issues/3426?journal_id=141882019-05-01T14:21:23Zlaforge
<ul><li><strong>Status</strong> changed from <i>New</i> to <i>In Progress</i></li></ul><p>I'm writing a testcase for this. It should be reasonably simple to send a MO XID with empty L3, and check the response.</p>
<p>note: We don't really have reasonable XID related tests yet.</p> OsmoSGSN - Bug #3426: gprs_llc_process_xid_ind() does not echo L3_PAR, breaks PDP activation for Motorola KRZRhttps://projects.osmocom.org/issues/3426?journal_id=200102020-10-19T12:50:59Zkeith
<ul><li><strong>Status</strong> changed from <i>In Progress</i> to <i>Feedback</i></li><li><strong>% Done</strong> changed from <i>0</i> to <i>90</i></li></ul><p>Hi <a class="user active" href="https://projects.osmocom.org/users/7">laforge</a> Was that test case ever merged? Maybe we can reference it and then close this.</p> OsmoSGSN - Bug #3426: gprs_llc_process_xid_ind() does not echo L3_PAR, breaks PDP activation for Motorola KRZRhttps://projects.osmocom.org/issues/3426?journal_id=200332020-10-20T07:19:57Zlaforge
<ul><li><strong>Status</strong> changed from <i>Feedback</i> to <i>In Progress</i></li></ul><p>keith wrote:</p>
<blockquote>
<p>Hi <a class="user active" href="https://projects.osmocom.org/users/7">laforge</a> Was that test case ever merged? Maybe we can reference it and then close this.</p>
</blockquote>
<pre>
commit 2aaac1b1d1655732055e6ad5da5965fe94af33e5
Author: Harald Welte <laforge@gnumonks.org>
Date: Thu May 2 10:02:53 2019 +0200
sgsn: Add initial XID handshake related tests
Change-Id: I5d4b3cba2fe05dffe10c843f16cfec343bc67b5f
</pre>
<p>That commit includes a case with empty L3: TC_xid_empty_l3</p> OsmoSGSN - Bug #3426: gprs_llc_process_xid_ind() does not echo L3_PAR, breaks PDP activation for Motorola KRZRhttps://projects.osmocom.org/issues/3426?journal_id=200342020-10-20T07:20:27Zlaforge
<ul><li><strong>Status</strong> changed from <i>In Progress</i> to <i>Resolved</i></li><li><strong>% Done</strong> changed from <i>90</i> to <i>100</i></li></ul>