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<p class="MsoNormal"><span style="color:#1F497D">You can use SpoofChecker.failsChecks() on a single identifier with MIXED_SCRIPT_CONFUSABLE and INVISIBLE checks to get much of the desired behavior – you don’t have to compare two identifiers.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">The library is open source, so producing a derivative to match the specific requirement shouldn’t be hard. I’ll volunteer to do the Java version.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">-Brad<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif""> Rick Andrews [mailto:Rick_Andrews@symantec.com]
<br>
<b>Sent:</b> Friday, August 24, 2012 4:32 PM<br>
<b>To:</b> Hill, Brad; public@cabforum.org<br>
<b>Subject:</b> RE: [cabfpub] Implementation of UTR-36 confusable text security considerations.<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span lang="EN-IE" style="color:#1F497D">Brad,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-IE" style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-IE" style="color:#1F497D">This helps, somewhat, but falls short in that it doesn’t provide code for all the checks in Bruce’s proposal document. And although the class contains a method to check if two strings are confusable,
we’re left wondering how we are to use that method. Clearly, the first string will be a U-label from the FQDN that the subscriber is enrolling for, but what’s the other? Would we have to check each U-label against each string from the Alexa One Million? Or
compare the U-label to every domain name in our db? It doesn’t seem like a practical solution.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-IE" style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-IE" style="color:#1F497D">-Rick<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-IE" style="color:#1F497D"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">
<a href="mailto:public-bounces@cabforum.org">public-bounces@cabforum.org</a> <a href="mailto:[mailto:public-bounces@cabforum.org]">
[mailto:public-bounces@cabforum.org]</a> <b>On Behalf Of </b>Hill, Brad<br>
<b>Sent:</b> Thursday, August 23, 2012 11:30 AM<br>
<b>To:</b> <a href="mailto:public@cabforum.org">public@cabforum.org</a><br>
<b>Subject:</b> [cabfpub] Implementation of UTR-36 confusable text security considerations.<o:p></o:p></span></p>
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<p class="MsoNormal"><span lang="EN-IE"><o:p> </o:p></span></p>
<p class="MsoNormal">In response to questions on today’s call about implementations about the confusable Unicode restrictions suggested for inclusion in BR 1.1, I can suggest the International Components for Unicode library:<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><a href="http://site.icu-project.org/">http://site.icu-project.org/</a><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">And, specifically, the SpoofChecker class:<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><a href="http://icu-project.org/apiref/icu4j/com/ibm/icu/text/SpoofChecker.html">http://icu-project.org/apiref/icu4j/com/ibm/icu/text/SpoofChecker.html</a>
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">And uspoof.h<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><a href="http://icu-project.org/apiref/icu4c/uspoof_8h.html">http://icu-project.org/apiref/icu4c/uspoof_8h.html</a><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">This doesn’t forbid the Left To Right Override character that I can tell from simple examination, but that’s an easy check to add with a regex or character search.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Brad Hill<o:p></o:p></p>
<p class="MsoNormal">Ecosystem Security<o:p></o:p></p>
<p class="MsoNormal">PayPal Information Risk Management<o:p></o:p></p>
<p class="MsoNormal">cell: 206.245.7844<o:p></o:p></p>
<p class="MsoNormal">skype/twitter: hillbrad<o:p></o:p></p>
<p class="MsoNormal">email: <a href="mailto:bhill@paypal-inc.com">bhill@paypal-inc.com</a><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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