Re: [TLS] Are the AEAD cipher suites a security trade-off win with TLS1.2?

Tom Ritter <tom@ritter.vg> Wed, 16 March 2016 16:46 UTC

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From: Tom Ritter <tom@ritter.vg>
Date: Wed, 16 Mar 2016 11:45:55 -0500
Message-ID: <CA+cU71mRGgRqFvT85ascQ6FmSuubNSifVLpw131GHBO5qf2M7g@mail.gmail.com>
To: Colm MacCárthaigh <colm@allcosts.net>
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Subject: Re: [TLS] Are the AEAD cipher suites a security trade-off win with TLS1.2?
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On 16 March 2016 at 09:52, Colm MacCárthaigh <colm@allcosts.net> wrote:
> At a minimum: could we agree that if a service/site is sensitive to privacy
> - it's reasonable for them to prefer AES-CBC; should they be penalized in
> SSL health analysis tools/reports for that configuration? it's not as
> flexible or useful as the padding in TLS1.3, but it's what we have.

If a site wants to actively do something to make length-hiding harder
- to the point where they're go in and prefer CBC ciphersuites - why
not just add 5 lines of code to a header template, to insert some
random data in a HTML comment?

I'm one of the biggest proponents for padding in TLS 1.3... and hope
to see it used to make deployments of length-hiding and traffic
analysis harder, so the HTML comment or similar tricks would be
easier, more robust, and not require site modifications.  But I don't
think going back to CBC mode is a good idea.

-tom

[TLS] Are the AEAD cipher suites a security trade… Colm MacCárthaigh
Re: [TLS] Are the AEAD cipher suites a security t… Tom Ritter
Re: [TLS] Are the AEAD cipher suites a security t… Colm MacCárthaigh
Re: [TLS] Are the AEAD cipher suites a security t… Alexandre Anzala-Yamajako
Re: [TLS] Are the AEAD cipher suites a security t… Paterson, Kenny
Re: [TLS] Are the AEAD cipher suites a security t… Adam Langley
Re: [TLS] Are the AEAD cipher suites a security t… Colm MacCárthaigh
Re: [TLS] Are the AEAD cipher suites a security t… Colm MacCárthaigh
Re: [TLS] Are the AEAD cipher suites a security t… Colm MacCárthaigh
Re: [TLS] Are the AEAD cipher suites a security t… Salz, Rich
Re: [TLS] Are the AEAD cipher suites a security t… Benjamin Beurdouche
Re: [TLS] Are the AEAD cipher suites a security t… Martin Rex
Re: [TLS] Are the AEAD cipher suites a security t… Martin Rex
Re: [TLS] Are the AEAD cipher suites a security t… Peter Gutmann
Re: [TLS] Are the AEAD cipher suites a security t… Harlan Lieberman-Berg
Re: [TLS] Are the AEAD cipher suites a security t… Eric Rescorla
Re: [TLS] Are the AEAD cipher suites a security t… Peter Gutmann