Re: [TLS] Computation of static secret in anonymous DH
Eric Rescorla <ekr@rtfm.com> Fri, 26 June 2015 19:31 UTC
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From: Eric Rescorla <ekr@rtfm.com>
Date: Fri, 26 Jun 2015 12:31:01 -0700
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To: Hugo Krawczyk <hugo@ee.technion.ac.il>
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Subject: Re: [TLS] Computation of static secret in anonymous DH
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Note: I have updated the WIP (and that's what I sent to Hugo) so it now contains the changes the values Hugo describes. On Fri, Jun 26, 2015 at 12:27 PM, Hugo Krawczyk <hugo@ee.technion.ac.il> wrote: > > 5) Application data uses xES as secret. AFAICT, leads to an attack. >> Should be master_secret (IIRC, was that way in earlier version)? >> > > Application data uses master_secret: See table before 7.2.1 where > application keys are derived from MS (should be denoted as master_secret; > the symbol MS is not used anymore) > I intend to change this to "master_secret", but the table got too wide and I need to figure out how to fix that :) > > >> >> 6) I think the key table should refer to inputs by their proper >> names, not e.g. referring to "xES" as "ES" when there is another >> thing named "ES" (that's confusing even with a note). >> > > The table is correct by referring to xSS and xES. > These are different values than SS and ES. > As their name indicates they are extracted versions of the latter, hence > stronger for use as keys and for extraction seeds. > > As Hugo indicates, these are now fixed in my working copy. -Ekr Hugo > > > >> 7) I think there should be helper function defined to do the >> label zero-padding, instead of it being just a note (just for >> clarity). >> >> >> -Ilari >> >> _______________________________________________ >> TLS mailing list >> TLS@ietf.org >> https://www.ietf.org/mailman/listinfo/tls >> > >
- [TLS] Computation of static secret in anonymous DH Douglas Stebila
- Re: [TLS] Computation of static secret in anonymo… Ilari Liusvaara
- Re: [TLS] Computation of static secret in anonymo… Eric Rescorla
- Re: [TLS] Computation of static secret in anonymo… Ilari Liusvaara
- Re: [TLS] Computation of static secret in anonymo… Eric Rescorla
- Re: [TLS] Computation of static secret in anonymo… Ilari Liusvaara
- Re: [TLS] Computation of static secret in anonymo… Eric Rescorla
- Re: [TLS] Computation of static secret in anonymo… Ilari Liusvaara
- Re: [TLS] Computation of static secret in anonymo… Eric Rescorla
- Re: [TLS] Computation of static secret in anonymo… Nico Williams
- Re: [TLS] Computation of static secret in anonymo… Eric Rescorla
- Re: [TLS] Computation of static secret in anonymo… Hugo Krawczyk
- Re: [TLS] Computation of static secret in anonymo… Eric Rescorla
- Re: [TLS] Computation of static secret in anonymo… Ilari Liusvaara
- Re: [TLS] Computation of static secret in anonymo… Eric Rescorla
- Re: [TLS] Computation of static secret in anonymo… Hubert Kario
- Re: [TLS] Computation of static secret in anonymo… Ilari Liusvaara
- Re: [TLS] Computation of static secret in anonymo… Nico Williams