Re: [TLS] RFC 8446: Correlating connections with ticket ages
Eric Rescorla <ekr@rtfm.com> Thu, 30 April 2020 13:04 UTC
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From: Eric Rescorla <ekr@rtfm.com>
Date: Thu, 30 Apr 2020 06:03:35 -0700
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To: research@bensmyth.com
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Subject: Re: [TLS] RFC 8446: Correlating connections with ticket ages
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On Thu, Apr 30, 2020 at 2:40 AM Ben Smyth <research@bensmyth.com> wrote: > Section 4.2.11.1 explains that: > > ...PskIdentity contains an obfuscated version of the ticket age formed by > taking the age in milliseconds and adding the "ticket_age_add"... This > addition prevents passive observers from correlating connections unless > tickets are reused. > > So: Correlations are possible when tickets are reused. But, what > connection correlations are prevented when tickets aren't reused? > If ticket X is issued at time T and then reused at time T+delta, it prevents the attacker from learning delta and hence from learning T. -Ekr > > Best regards, > > Ben > -- > TLS 1.3 tutorial: https://bensmyth.com/publications/2019-TLS-tutorial/ > > _______________________________________________ > TLS mailing list > TLS@ietf.org > https://www.ietf.org/mailman/listinfo/tls >
- [TLS] RFC 8446: Correlating connections with tick… Ben Smyth
- Re: [TLS] RFC 8446: Correlating connections with … Eric Rescorla