<p>fixeria has uploaded this change for <strong>review</strong>.</p><p><a href="https://gerrit.osmocom.org/c/osmo-ttcn3-hacks/+/26404">View Change</a></p><pre style="font-family: monospace,monospace; white-space: pre-wrap;">msc/BSC_ConnectionHandler: refactor and split f_mm_common()<br><br>Reduce nesting and improve readability by splitting GERAN/UTRAN<br>specific CMC/SMC message handling into separate functions.<br><br>Change-Id: Ib7ebe8fd675295beb02cadebb19d8465dffeb732<br>Related: OS#5333<br>---<br>M msc/BSC_ConnectionHandler.ttcn<br>1 file changed, 69 insertions(+), 57 deletions(-)<br><br></pre><pre style="font-family: monospace,monospace; white-space: pre-wrap;">git pull ssh://gerrit.osmocom.org:29418/osmo-ttcn3-hacks refs/changes/04/26404/1</pre><pre style="font-family: monospace,monospace; white-space: pre-wrap;"><span>diff --git a/msc/BSC_ConnectionHandler.ttcn b/msc/BSC_ConnectionHandler.ttcn</span><br><span>index 2f270ca..873ec5b 100644</span><br><span>--- a/msc/BSC_ConnectionHandler.ttcn</span><br><span>+++ b/msc/BSC_ConnectionHandler.ttcn</span><br><span>@@ -611,68 +611,80 @@</span><br><span> }</span><br><span> </span><br><span> </span><br><span style="color: hsl(120, 100%, 40%);">+private function f_mm_ciph_geran() runs on BSC_ConnHdlr</span><br><span style="color: hsl(120, 100%, 40%);">+{</span><br><span style="color: hsl(120, 100%, 40%);">+ var template BSSMAP_IE_EncryptionInformation encryptionInformation;</span><br><span style="color: hsl(120, 100%, 40%);">+ var template BSSMAP_IE_ChosenEncryptionAlgorithm chosenEncryptionAlgorithm;</span><br><span style="color: hsl(120, 100%, 40%);">+ var template BSSMAP_IE_KC128 kC128;</span><br><span style="color: hsl(120, 100%, 40%);">+ var OCT1 a5_perm_alg;</span><br><span style="color: hsl(120, 100%, 40%);">+ var PDU_BSSAP pdu;</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ if (g_pars.net.expect_ciph) {</span><br><span style="color: hsl(120, 100%, 40%);">+ /* There is nothing to do */</span><br><span style="color: hsl(120, 100%, 40%);">+ return;</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ f_get_expected_encryption(encryptionInformation, chosenEncryptionAlgorithm, kC128, a5_perm_alg);</span><br><span style="color: hsl(120, 100%, 40%);">+ alt {</span><br><span style="color: hsl(120, 100%, 40%);">+ [] BSSAP.receive(tr_BSSMAP_CipherModeCmd2(encryptionInformation, kC128)) -> value pdu {</span><br><span style="color: hsl(120, 100%, 40%);">+ var OCT1 a5_chosen := f_best_alg_from_mask(a5_perm_alg);</span><br><span style="color: hsl(120, 100%, 40%);">+ var integer a5_nr := f_alg_from_mask(a5_chosen);</span><br><span style="color: hsl(120, 100%, 40%);">+ BSSAP.send(ts_BSSMAP_CipherModeCompl(int2oct(a5_nr+1, 1)));</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+ [] BSSAP.receive(tr_BSSMAP_CipherModeCmd2) -> value pdu {</span><br><span style="color: hsl(120, 100%, 40%);">+ log("Error: Ciphering Mode Command with unexpected content. Expected: ",</span><br><span style="color: hsl(120, 100%, 40%);">+ tr_BSSMAP_CipherModeCmd2(encryptionInformation, kC128), " got: ", pdu);</span><br><span style="color: hsl(120, 100%, 40%);">+ setverdict(fail, "Ciphering Mode Command with unexpected content.");</span><br><span style="color: hsl(120, 100%, 40%);">+ mtc.stop;</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+ [] BSSAP.receive(tr_BSSMAP_ClassmarkRequest) {</span><br><span style="color: hsl(120, 100%, 40%);">+ BSSAP.send(ts_BSSMAP_ClassmarkUpd(g_pars.cm2, g_pars.cm3))</span><br><span style="color: hsl(120, 100%, 40%);">+ repeat;</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+ /* FIXME: Send the best available algorithm */</span><br><span style="color: hsl(120, 100%, 40%);">+}</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+private function f_mm_ciph_utran() runs on BSC_ConnHdlr</span><br><span style="color: hsl(120, 100%, 40%);">+{</span><br><span style="color: hsl(120, 100%, 40%);">+ alt {</span><br><span style="color: hsl(120, 100%, 40%);">+ [g_pars.net.expect_ciph] BSSAP.receive(tr_RANAP_SecurityModeCmdEnc(uia_algs := ?,</span><br><span style="color: hsl(120, 100%, 40%);">+ uia_key := oct2bit(g_pars.vec.ik),</span><br><span style="color: hsl(120, 100%, 40%);">+ key_sts := ?,</span><br><span style="color: hsl(120, 100%, 40%);">+ uea_algs := ?,</span><br><span style="color: hsl(120, 100%, 40%);">+ uea_key := oct2bit(g_pars.vec.ck))) {</span><br><span style="color: hsl(120, 100%, 40%);">+ var IntegrityProtectionAlgorithm uia_chosen := 0; /*standard_UMTS_integrity_algorithm_UIA1*/</span><br><span style="color: hsl(120, 100%, 40%);">+ var EncryptionAlgorithm uea_chosen := 1; /*standard_UMTS_encryption_algorith_UEA1*/</span><br><span style="color: hsl(120, 100%, 40%);">+ BSSAP.send(ts_RANAP_SecurityModeCompleteEnc(uia_chosen, uea_chosen));</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+ [g_pars.net.expect_ciph] BSSAP.receive(tr_RANAP_SecurityModeCmdEnc(?,?,?,?,?)) {</span><br><span style="color: hsl(120, 100%, 40%);">+ setverdict(fail, "Invalid SecurityModeCommand (ciphering case)");</span><br><span style="color: hsl(120, 100%, 40%);">+ mtc.stop;</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+ [not g_pars.net.expect_ciph] BSSAP.receive(tr_RANAP_SecurityModeCmd(uia_algs := ?,</span><br><span style="color: hsl(120, 100%, 40%);">+ uia_key := oct2bit(g_pars.vec.ik),</span><br><span style="color: hsl(120, 100%, 40%);">+ key_sts := ?)) {</span><br><span style="color: hsl(120, 100%, 40%);">+ var IntegrityProtectionAlgorithm uia_chosen := 0; /*standard_UMTS_integrity_algorithm_UIA1;*/</span><br><span style="color: hsl(120, 100%, 40%);">+ BSSAP.send(ts_RANAP_SecurityModeComplete(uia_chosen));</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+ [not g_pars.net.expect_ciph] BSSAP.receive(tr_RANAP_SecurityModeCmd(?,?,?)) {</span><br><span style="color: hsl(120, 100%, 40%);">+ setverdict(fail, "Invalid SecurityModeCommand (non-ciphering case)");</span><br><span style="color: hsl(120, 100%, 40%);">+ mtc.stop;</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+}</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span> function f_mm_common() runs on BSC_ConnHdlr</span><br><span> {</span><br><span> f_mm_auth();</span><br><span style="color: hsl(0, 100%, 40%);">- if (g_pars.ran_is_geran) {</span><br><span style="color: hsl(0, 100%, 40%);">- if (g_pars.net.expect_ciph) {</span><br><span style="color: hsl(0, 100%, 40%);">- var template BSSMAP_IE_EncryptionInformation encryptionInformation;</span><br><span style="color: hsl(0, 100%, 40%);">- var template BSSMAP_IE_ChosenEncryptionAlgorithm chosenEncryptionAlgorithm;</span><br><span style="color: hsl(0, 100%, 40%);">- var template BSSMAP_IE_KC128 kC128;</span><br><span style="color: hsl(0, 100%, 40%);">- var OCT1 a5_perm_alg;</span><br><span style="color: hsl(0, 100%, 40%);">- f_get_expected_encryption(encryptionInformation, chosenEncryptionAlgorithm, kC128, a5_perm_alg);</span><br><span> </span><br><span style="color: hsl(0, 100%, 40%);">- var PDU_BSSAP pdu;</span><br><span style="color: hsl(0, 100%, 40%);">- var template PDU_BSSAP expect_ciph_mode_cmd := tr_BSSMAP_CipherModeCmd2(encryptionInformation, kC128);</span><br><span style="color: hsl(0, 100%, 40%);">- alt {</span><br><span style="color: hsl(0, 100%, 40%);">- [] BSSAP.receive(expect_ciph_mode_cmd) -> value pdu {</span><br><span style="color: hsl(0, 100%, 40%);">- var OCT1 a5_chosen := f_best_alg_from_mask(a5_perm_alg);</span><br><span style="color: hsl(0, 100%, 40%);">- var integer a5_nr := f_alg_from_mask(a5_chosen);</span><br><span style="color: hsl(0, 100%, 40%);">- BSSAP.send(ts_BSSMAP_CipherModeCompl(int2oct(a5_nr+1, 1)));</span><br><span style="color: hsl(0, 100%, 40%);">- }</span><br><span style="color: hsl(0, 100%, 40%);">- [] BSSAP.receive(tr_BSSMAP_CipherModeCmd2) -> value pdu {</span><br><span style="color: hsl(0, 100%, 40%);">- log("Error: Ciphering Mode Command with unexpected content. Expected: ",</span><br><span style="color: hsl(0, 100%, 40%);">- expect_ciph_mode_cmd, " got: ", pdu);</span><br><span style="color: hsl(0, 100%, 40%);">- setverdict(fail, "Ciphering Mode Command with unexpected content.");</span><br><span style="color: hsl(0, 100%, 40%);">- mtc.stop;</span><br><span style="color: hsl(0, 100%, 40%);">- }</span><br><span style="color: hsl(0, 100%, 40%);">- [] BSSAP.receive(tr_BSSMAP_ClassmarkRequest) {</span><br><span style="color: hsl(0, 100%, 40%);">- BSSAP.send(ts_BSSMAP_ClassmarkUpd(g_pars.cm2, g_pars.cm3))</span><br><span style="color: hsl(0, 100%, 40%);">- repeat;</span><br><span style="color: hsl(0, 100%, 40%);">- }</span><br><span style="color: hsl(0, 100%, 40%);">- }</span><br><span style="color: hsl(0, 100%, 40%);">- /* FIXME: Send the best available algorithm */</span><br><span style="color: hsl(0, 100%, 40%);">- }</span><br><span style="color: hsl(0, 100%, 40%);">- f_expect_common_id();</span><br><span style="color: hsl(0, 100%, 40%);">- } else { /* UTRAN */</span><br><span style="color: hsl(0, 100%, 40%);">- alt {</span><br><span style="color: hsl(0, 100%, 40%);">- [g_pars.net.expect_ciph] BSSAP.receive(tr_RANAP_SecurityModeCmdEnc(uia_algs := ?,</span><br><span style="color: hsl(0, 100%, 40%);">- uia_key := oct2bit(g_pars.vec.ik),</span><br><span style="color: hsl(0, 100%, 40%);">- key_sts := ?,</span><br><span style="color: hsl(0, 100%, 40%);">- uea_algs := ?,</span><br><span style="color: hsl(0, 100%, 40%);">- uea_key := oct2bit(g_pars.vec.ck))) {</span><br><span style="color: hsl(0, 100%, 40%);">- var IntegrityProtectionAlgorithm uia_chosen := 0; /*standard_UMTS_integrity_algorithm_UIA1*/</span><br><span style="color: hsl(0, 100%, 40%);">- var EncryptionAlgorithm uea_chosen := 1; /*standard_UMTS_encryption_algorith_UEA1*/</span><br><span style="color: hsl(0, 100%, 40%);">- BSSAP.send(ts_RANAP_SecurityModeCompleteEnc(uia_chosen, uea_chosen));</span><br><span style="color: hsl(0, 100%, 40%);">- f_expect_common_id();</span><br><span style="color: hsl(0, 100%, 40%);">- }</span><br><span style="color: hsl(0, 100%, 40%);">- [g_pars.net.expect_ciph] BSSAP.receive(tr_RANAP_SecurityModeCmdEnc(?,?,?,?,?)) {</span><br><span style="color: hsl(0, 100%, 40%);">- setverdict(fail, "Invalid SecurityModeCommand (ciphering case)");</span><br><span style="color: hsl(0, 100%, 40%);">- mtc.stop;</span><br><span style="color: hsl(0, 100%, 40%);">- }</span><br><span style="color: hsl(0, 100%, 40%);">- [not g_pars.net.expect_ciph] BSSAP.receive(tr_RANAP_SecurityModeCmd(uia_algs := ?,</span><br><span style="color: hsl(0, 100%, 40%);">- uia_key := oct2bit(g_pars.vec.ik),</span><br><span style="color: hsl(0, 100%, 40%);">- key_sts := ?)) {</span><br><span style="color: hsl(0, 100%, 40%);">- var IntegrityProtectionAlgorithm uia_chosen := 0; /*standard_UMTS_integrity_algorithm_UIA1;*/</span><br><span style="color: hsl(0, 100%, 40%);">- BSSAP.send(ts_RANAP_SecurityModeComplete(uia_chosen));</span><br><span style="color: hsl(0, 100%, 40%);">- f_expect_common_id();</span><br><span style="color: hsl(0, 100%, 40%);">- }</span><br><span style="color: hsl(0, 100%, 40%);">- [not g_pars.net.expect_ciph] BSSAP.receive(tr_RANAP_SecurityModeCmd(?,?,?)) {</span><br><span style="color: hsl(0, 100%, 40%);">- setverdict(fail, "Invalid SecurityModeCommand (non-ciphering case)");</span><br><span style="color: hsl(0, 100%, 40%);">- mtc.stop;</span><br><span style="color: hsl(0, 100%, 40%);">- }</span><br><span style="color: hsl(0, 100%, 40%);">- }</span><br><span style="color: hsl(120, 100%, 40%);">+ if (g_pars.ran_is_geran) {</span><br><span style="color: hsl(120, 100%, 40%);">+ f_mm_ciph_geran();</span><br><span style="color: hsl(120, 100%, 40%);">+ } else {</span><br><span style="color: hsl(120, 100%, 40%);">+ f_mm_ciph_utran();</span><br><span> }</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ f_expect_common_id();</span><br><span> }</span><br><span> </span><br><span> function f_expect_mm_info() runs on BSC_ConnHdlr {</span><br><span></span><br></pre><p>To view, visit <a href="https://gerrit.osmocom.org/c/osmo-ttcn3-hacks/+/26404">change 26404</a>. 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<div style="display:none"> Gerrit-Project: osmo-ttcn3-hacks </div>
<div style="display:none"> Gerrit-Branch: master </div>
<div style="display:none"> Gerrit-Change-Id: Ib7ebe8fd675295beb02cadebb19d8465dffeb732 </div>
<div style="display:none"> Gerrit-Change-Number: 26404 </div>
<div style="display:none"> Gerrit-PatchSet: 1 </div>
<div style="display:none"> Gerrit-Owner: fixeria <vyanitskiy@sysmocom.de> </div>
<div style="display:none"> Gerrit-MessageType: newchange </div>