<html><head><meta http-equiv="Content-Type" content="text/html charset=us-ascii"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;"><div><div>One more thing:</div><div><br></div><div>On Sep 27, 2014, at 6:04 PM, Greg <<a href="mailto:greg@kinostudios.com">greg@kinostudios.com</a>> wrote:</div></div><blockquote type="cite"><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;">No, that is not true.<div><br></div><div>The SCTs in the certificate are the ones the MITM puts there.</div><div><br></div><div>They are not the ones you're thinking of (that whatever trustworthy entity chose).</div></div></blockquote><div><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;"><div><br></div><div>Furthermore, the SCTs don't matter to begin with, as has been repeatedly explained in this thread and elsewhere.</div><div><br></div><div>Creating a bogus cert doesn't need to result in any fork of a log. The log will be shown to everyone, they'll run their proofs, and they'll see that the certificate is legitimate even though it is not.</div><div><br></div><div>The only person who decides whether the certificate is legitimate or not is the domain owner.</div><div><br></div><div>Nobody else.</div><div><br></div><div>Currently, nothing in the CT proposal detects these MITM attacks, before, during, or after they happen.</div><div><br></div><div>The one thing that might help is if the SCTs are gossiped upon change:</div><div><br></div><div><a href="http://www.ietf.org/mail-archive/web/trans/current/msg00600.html">http://www.ietf.org/mail-archive/web/trans/current/msg00600.html</a></div><div><br></div><div>That would require changing how TLS works, and actually could be done without implementing much else besides gossip.</div><div><br></div><div>Regards,</div><div>Greg</div></div></div><div>
<br class="Apple-interchange-newline"><span style="color: rgb(0, 0, 0); font-family: Helvetica; font-size: 14px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; display: inline !important; float: none;">--</span><br style="color: rgb(0, 0, 0); font-family: Helvetica; font-size: 14px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px;"><span style="color: rgb(0, 0, 0); font-family: Helvetica; font-size: 14px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; display: inline !important; float: none;">Please do not email me anything that you are not comfortable also sharing</span><span style="color: rgb(0, 0, 0); font-family: Helvetica; font-size: 14px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; display: inline !important; float: none;"> with the NSA.</span>
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<br><div><div>On Sep 27, 2014, at 6:04 PM, Greg <<a href="mailto:greg@kinostudios.com">greg@kinostudios.com</a>> wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><meta http-equiv="Content-Type" content="text/html charset=us-ascii"><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;"><div>On Sep 27, 2014, at 5:23 PM, Theodore Ts'o <<a href="mailto:tytso@mit.edu">tytso@mit.edu</a>> wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite">On Sat, Sep 27, 2014 at 03:15:25PM -0700, Greg wrote:<br><blockquote type="cite"><br><a href="https://blog.okturtles.com/2014/09/the-trouble-with-certificate-transparency/">https://blog.okturtles.com/2014/09/the-trouble-with-certificate-transparency/</a><br></blockquote><br>I've looked at the blog entry, and compared it to the Certificate<br>Transparency descriptions, and I believe that CT does add value. Is<br>it a silver bullet that solves all problems? Of course not.<br><br>The fact that anyone can run a log, and a certificate (or TLS session)<br>should include multiple SCT's, including some from trusted third-party<br>log services, means that if a government agency wants to order a CA to<br>issue a bogus cert via a NSL order, it would now need to send NSL's to<br>N log services so they could also issue SCT's and create forked Merkle<br>Hash Trees.</blockquote><div><br></div>No, that is not true.<div><br></div><div>The SCTs in the certificate are the ones the MITM puts there.</div><div><br></div><div>They are not the ones you're thinking of (that whatever trustworthy entity chose).</div><div><br></div><div>- Greg<br><div>
<br class="Apple-interchange-newline"><span style="font-family: Helvetica; font-size: 14px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: inline !important;">--</span><br style="font-family: Helvetica; font-size: 14px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px;"><span style="font-family: Helvetica; font-size: 14px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: inline !important;">Please do not email me anything that you are not comfortable also sharing</span><span style="font-family: Helvetica; font-size: 14px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: inline !important;"> with the NSA.</span>
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