[TLS] padding bug (was: Re: Requesting feedback on TACK draft)
Peter Saint-Andre <stpeter@stpeter.im> Sun, 08 September 2013 02:59 UTC
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Date: Sat, 07 Sep 2013 20:59:20 -0600
From: Peter Saint-Andre <stpeter@stpeter.im>
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Subject: [TLS] padding bug (was: Re: Requesting feedback on TACK draft)
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-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 [old thread alert!] On 7/1/13 3:02 AM, Lewis, Nick wrote: >> While people are looking at that, there's also the >> encrypt-then-MAC draft, >> http://www.ietf.org/internet-drafts/draft-gutmann-tls-encrypt-then-mac-03.txt, >> >> which has been stable for about as long, has already been deployed by >> several vendors, and for which TLS extension 0x10 has been de >> facto claimed, so it'd be good to get this published to >> legitimise the use (and to document what's already being deployed >> in production). > > As I recall there were three proposals for resolving the padding > bug in TLS > > 1. An extension for Pad First (i.e. padding before an > otherwise standard TLS mode of operation) > > 2. An extension for Encrypt-then-MAC (i.e. this draft) > > 3. The replacement of each existing cipher suite with an > equivalent AEAD one > > Was any consensus achieved as to the best approach? I never saw further discussion on this topic. Are there I-Ds for each approach? #3 seems onerous to me (and doubling the number of cipher suites doesn't seem like a desirable outcome), and as far as I can tell there's no specification for #1. Although I am not a TLS expert, the Encrypt-then-MAC I-D referenced above seems reasonable, it neatly solves a real-world problem, and we have running code; thus IMHO formalization of this approach deserves to be considered in the WG. Peter - -- Peter Saint-Andre https://stpeter.im/ -----BEGIN PGP SIGNATURE----- Version: GnuPG/MacGPG2 v2.0.19 (Darwin) Comment: GPGTools - http://gpgtools.org Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iQIcBAEBAgAGBQJSK+gIAAoJEOoGpJErxa2plBoP/iUBRQUD29mmNlZkdAHhsFAL FKcBXGt6xPmUi/uNuf+p9NUz5MB4MIXJ6urkdrAy5Lk2828ll7aUoJy0muQYcNuR YdCn8VP9zlKhhzmvr3ENJkCLUg0UG+hU9CkIGXkSNUo1k3IrhxYwFQ4fvGHMhy8m n7ba5+mpLHxu9kaqbrhDIkR5gOMDLGdq3fG5y9iuEiAEobFUr4/yKDKIkXbfBrTM kKHXR4tlSChTphHMjlSuq4drILkqQ//Bpsn8fK5P9pQ1BvF9Wlo7xsSkQ4LayLvs dhNn863SWfBtdq3u2AxtdsY+mPxf/6qO5B7R+N7lawfe2bnSc/24db+grROxES6D o9rQjuFj0ReF+2bKhbxxTh/VRzCpu0L5TNzOTxnx267OW/+HmlmDTgKc2QpcM0F2 gxgkqGUZpRpZxAr21V2giub7HJ0KeN2kNfzUNaMpZaJD1MvvYZsw5sDCwEDMlUCj qbTVWDere5p+3D4gMmRSGQroO8eUKVs+hrLpAlMIHvHqtVPuqFxZXlBSA9Ev6KkK KhMeaCA9RoqkVAI0VQnuz03bduv4eWU6TLPbII6MharvM9ArPMSX8ZI39e32yWos QLZ44zt+VfoTkpZ0S9w78pWTRQDt8zdWiRx+pAoadHUlRY5JDJ0HJcoU9MphUhg/ yDu4w8yNTA/m1Z+kXmR/ =s05+ -----END PGP SIGNATURE-----
- [TLS] Requesting feedback on TACK draft Trevor Perrin
- Re: [TLS] Requesting feedback on TACK draft Peter Gutmann
- Re: [TLS] Requesting feedback on TACK draft Lewis, Nick
- [TLS] padding bug (was: Re: Requesting feedback o… Peter Saint-Andre
- Re: [TLS] padding bug Dr Stephen Henson
- Re: [TLS] padding bug Dr Stephen Henson
- Re: [TLS] padding bug Nikos Mavrogiannopoulos
- Re: [TLS] padding bug Ben Laurie
- Re: [TLS] padding bug Eric Rescorla
- Re: [TLS] padding bug (was: Re: Requesting feedba… Alfredo Pironti
- Re: [TLS] padding bug Ben Laurie
- Re: [TLS] padding bug Yaron Sheffer
- Re: [TLS] padding bug (was: Re: Requesting feedba… Paterson, Kenny
- Re: [TLS] padding bug Ben Laurie
- Re: [TLS] padding bug Adam Langley
- Re: [TLS] padding bug Ben Laurie
- Re: [TLS] padding bug Dr Stephen Henson
- Re: [TLS] padding bug Nico Williams
- Re: [TLS] padding bug Nikos Mavrogiannopoulos
- Re: [TLS] padding bug Blumenthal, Uri - 0558 - MITLL
- Re: [TLS] padding bug (was: Re: Requesting feedba… Bodo Moeller
- Re: [TLS] padding bug (was: Re: Requesting feedba… Paterson, Kenny
- Re: [TLS] padding bug Brian Smith
- Re: [TLS] padding bug Martin Rex
- [TLS] Encrypt-then-MAC again (was Re: padding bug) Michael D'Errico
- Re: [TLS] Encrypt-then-MAC again (was Re: padding… Watson Ladd
- Re: [TLS] Encrypt-then-MAC again (was Re: padding… Paterson, Kenny
- Re: [TLS] Encrypt-then-MAC again (was Re: padding… Michael D'Errico
- Re: [TLS] Encrypt-then-MAC again (was Re: padding… Martin Rex
- Re: [TLS] Encrypt-then-MAC again (was Re: padding… Nikos Mavrogiannopoulos
- Re: [TLS] Encrypt-then-MAC again (was Re: padding… Ralf Skyper Kaiser
- Re: [TLS] Encrypt-then-MAC again (was Re: padding… Martin Rex
- Re: [TLS] Encrypt-then-MAC again (was Re: padding… Martin Rex
- Re: [TLS] Encrypt-then-MAC again (was Re: padding… Ben Laurie
- Re: [TLS] Encrypt-then-MAC again (was Re: padding… Bryan C. Geraghty
- Re: [TLS] Encrypt-then-MAC again (was Re: padding… Nikos Mavrogiannopoulos
- [TLS] Would this fix RC4 again? (was Re: Encrypt-… Michael D'Errico
- Re: [TLS] Would this fix RC4 again? (was Re: Encr… Watson Ladd
- Re: [TLS] Would this fix RC4 again? (was Re: Encr… Paterson, Kenny
- Re: [TLS] Would this fix RC4 again? (was Re: Encr… Nikos Mavrogiannopoulos
- Re: [TLS] Would this fix RC4 again? (was Re: Encr… Jacob Appelbaum
- Re: [TLS] Encrypt-then-MAC again (was Re: padding… Martin Rex
- Re: [TLS] Encrypt-then-MAC again (was Re: padding… Ralf Skyper Kaiser
- Re: [TLS] Encrypt-then-MAC again (was Re: padding… Nikos Mavrogiannopoulos
- Re: [TLS] Encrypt-then-MAC again (was Re: padding… Ralf Skyper Kaiser
- Re: [TLS] Encrypt-then-MAC again (was Re: padding… Martin Rex
- Re: [TLS] Encrypt-then-MAC again (was Re: padding… Martin Rex
- Re: [TLS] Encrypt-then-MAC again (was Re: padding… Ralf Skyper Kaiser
- Re: [TLS] Encrypt-then-MAC again (was Re: padding… Alex Elsayed
- Re: [TLS] Encrypt-then-MAC again (was Re: padding… Paterson, Kenny
- Re: [TLS] Encrypt-then-MAC again (was Re: padding… Martin Rex
- Re: [TLS] Encrypt-then-MAC again (was Re: padding… Martin Rex
- [TLS] draft-mavrogiannopoulos-new-tls-padding-00 Martin Rex
- Re: [TLS] draft-mavrogiannopoulos-new-tls-padding… Nikos Mavrogiannopoulos