Re: [TLS] encrypted content type and padding
Daniel Kahn Gillmor <dkg@fifthhorseman.net> Mon, 21 September 2015 15:38 UTC
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From: Daniel Kahn Gillmor <dkg@fifthhorseman.net>
To: Watson Ladd <watsonbladd@gmail.com>, noloader@gmail.com
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Date: Mon, 21 Sep 2015 07:06:44 -0700
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Cc: IETF TLS Working Group <tls@ietf.org>
Subject: Re: [TLS] encrypted content type and padding
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On Mon 2015-09-21 04:43:27 -0700, Watson Ladd <watsonbladd@gmail.com> wrote: > Is this actually true in the second pull request? No: a moment of > actually reading reveals that the string is inside an AEAD encrypted > packet. There is no way in which this padding could be modified for > use in a side-channel attack. In both pull requests, the padding is inside the AEAD encrypted packet. The intent, after all, is to create a mechanism that provides uncertainty about the length of the cleartext. See, for example: I Know Why You Went to the Clinic: Risks and Realization of HTTPS Traffic Analysis by Brad Miller, Ling Huang, A. D. Joseph, and J. D. Tygar http://arxiv.org/abs/1403.0297 --dkg
- [TLS] encrypted content type and padding Daniel Kahn Gillmor
- Re: [TLS] encrypted content type and padding Jeffrey Walton
- Re: [TLS] encrypted content type and padding Watson Ladd
- Re: [TLS] encrypted content type and padding Daniel Kahn Gillmor
- Re: [TLS] encrypted content type and padding Dave Garrett