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<p class="MsoNormal">Jeremy and Ben – sorry we didn’t ask these questions last week, but I was travelling and didn’t realize the comment period had begun.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">(1) We are concerned that under Ballot 144 there could be two .onion certs with the SAME domain but identifying two DIFFERENT subjects.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">For example, Evil Corp. and Angel Corp. could each submit a request for a .onion cert and get the same domain:
<u>[same 16 digit hash of their public keys].onion</u> if their public keys hash to the same value. One cert would say O=Evil Corp. the other would say O=Angel Corp., so that a .onion domain would not be uniquely identified with one subject. While unlikely,
it could happen.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">How does Tor resolve this if the same .onion domain is assigned to multiple, different subjects? If someone types in [16 digit hash].onion and that could lead to multiple Tor locations, how does Tor decide where to direct the user?
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">(2) Does this also create an opportunity for a hacker? For example, one of the .onion domains in the SANs field of the Facebook cert you created is
<u>*.xx.fbcdn23dssr3jqnq.onion</u> – could a hacker create a public key that would hash to the same value in order to get a cert with the same .onion domain and imitate the Facebook cert? (This is maybe the more serious case.)<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">(3) Another concern is there is no central registry to identify the owner of a .onion domain (of course, there could be multiple owners of the domain under the scenario above). If there is no Subject info in the O field, etc., with no
registry there is no real way to contact the domain (or cert owner). <o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Any information you can provide on these point will be very helpful.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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