Hello Harald Welte, Jenkins Builder,

I'd like you to reexamine a change.  Please visit

    https://gerrit.osmocom.org/6314

to look at the new patch set (#2).

msc: convert bssmap chipher to rsl chiper representation

The representation of the chiphering algorithm is different bssmap
and RSL. BSSMAP uses a bitmask and RSL a numeric value. For A50 and
A51 the values match up by coincidence, from A5/2 onwards they differ.

- Add a function to convert the BSSMAP representation to the RSL
  representation and use the converted value to set up the temlate
  for the expected RSL message

Change-Id: I274c1ff0b5636c48411f994f918e783b468cb3be
---
M bsc/MSC_ConnectionHandler.ttcn
1 file changed, 47 insertions(+), 1 deletion(-)


  git pull ssh://gerrit.osmocom.org:29418/osmo-ttcn3-hacks 
refs/changes/14/6314/2

diff --git a/bsc/MSC_ConnectionHandler.ttcn b/bsc/MSC_ConnectionHandler.ttcn
index 5a645bd..51aebd2 100644
--- a/bsc/MSC_ConnectionHandler.ttcn
+++ b/bsc/MSC_ConnectionHandler.ttcn
@@ -323,19 +323,65 @@
        f_rsl_send_l3(l3, link_id, chan_nr);
 }
 
+/* Convert the chipher representation on BSSMAP to the representation used on 
RSL */
+function f_chipher_mode_bssmap_to_rsl(OCT1 alg_bssmap) return OCT1
+{
+       /* A5 0 */
+       if (alg_bssmap == '01'O) {
+               return '01'O;
+       }
+       /* A5 1 */
+       else if (alg_bssmap == '02'O) {
+               return '02'O;
+       }
+       /* A5 2 */
+       else if (alg_bssmap == '04'O) {
+               return '03'O;
+       }
+       /* A5 3 */
+       else if (alg_bssmap == '08'O) {
+               return '04'O;
+       }
+       /* A5 4 */
+       else if (alg_bssmap == '10'O) {
+               return '05'O;
+       }
+       /* A5 5 */
+       else if (alg_bssmap == '20'O) {
+               return '06'O;
+       }
+       /* A5 6 */
+       else if (alg_bssmap == '40'O) {
+               return '07'O;
+       }
+       /* A5 7 */
+       else if (alg_bssmap == '80'O) {
+               return '08'O;
+       } else {
+               setverdict(fail, "Unexpected Encryption Algorithm");
+               return '00'O;
+       }
+}
+
 function f_cipher_mode(OCT1 alg, OCT8 key, template OCT16 kc128 := omit, 
boolean exp_fail := false)
 runs on MSC_ConnHdlr {
        var PDU_BSSAP bssap;
        var RSL_Message rsl;
+       var OCT1 alg_rsl;
 
        if (isvalue(kc128)) {
                BSSAP.send(ts_BSSMAP_CipherModeCmdKc128(alg, key, 
valueof(kc128)));
        } else {
                BSSAP.send(ts_BSSMAP_CipherModeCmd(alg, key));
        }
+
+       /* RSL uses a different representation of the encryption algorithm,
+        * so we need to convert first */
+       alg_rsl := f_chipher_mode_bssmap_to_rsl(alg);
+
        alt {
        /* RSL/UE Side */
-       [] RSL.receive(tr_RSL_ENCR_CMD(g_chan_nr, ?, alg, key)) -> value rsl {
+       [] RSL.receive(tr_RSL_ENCR_CMD(g_chan_nr, ?, alg_rsl, key)) -> value 
rsl {
                var PDU_ML3_NW_MS l3 := 
dec_PDU_ML3_NW_MS(rsl.ies[3].body.l3_info.payload);
                log("Rx L3 from net: ", l3);
                if (ischosen(l3.msgs.rrm.cipheringModeCommand)) {

-- 
To view, visit https://gerrit.osmocom.org/6314
To unsubscribe, visit https://gerrit.osmocom.org/settings

Gerrit-MessageType: newpatchset
Gerrit-Change-Id: I274c1ff0b5636c48411f994f918e783b468cb3be
Gerrit-PatchSet: 2
Gerrit-Project: osmo-ttcn3-hacks
Gerrit-Branch: master
Gerrit-Owner: dexter <pma...@sysmocom.de>
Gerrit-Reviewer: Harald Welte <lafo...@gnumonks.org>
Gerrit-Reviewer: Jenkins Builder

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