Re: [TLS] draft-sheffer-tls-bcp: DH recommendations
mrex@sap.com (Martin Rex) Thu, 19 September 2013 02:06 UTC
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Date: Thu, 19 Sep 2013 04:06:42 +0200
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Subject: Re: [TLS] draft-sheffer-tls-bcp: DH recommendations
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Following up to myself: > > The TLS WG could have easly provided an adequate PFS solution > many years ago that could be trivially enabled for all existing > implementations. Ephermeral RSA. 99% of the code is already > present in all implementations, because this is used in the > RSA_EXP cipher suites. > > http://www.ietf.org/mail-archive/web/tls/current/msg01541.html > > (EC)DHE is a mess, because both, servers and clients will regularly > have to regenerate new keys, and there are going to be severl > different keys necessary for the preferences of various servers > and sometimes, the client-side key generation will have to be > performed inline. How many different keys will clients need > for ECDHE? > > With Ephemeral RSA, only the server has to generate the temporary > RSA keypair, and can *ALWAYS* generate the ephemeral RSA keypair out-of-band. What I had not remembered from the past discussion, and just found in a later reply from EKR: http://www.ietf.org/mail-archive/web/tls/current/msg01556.html was the design "feature" (I believe it is a defect), that the ephemeral key exchange in the server key exchange handshake message exists only in a an exteremely paranoid variant, requiring an additional private key operation for every handshake. It would really help if client and server could negotiate the use of alternative "signed parameters format" for ephemeral (RSA) keys that do not require a seperate signature (=private key operation) for each handshake, but where the signed parameters could be reused for several hours, maybe using a time-based indicator for the freshness of the ephemeral keypair. -Martin
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Yoav Nir
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Stephen Farrell
- [TLS] draft-sheffer-tls-bcp: DH recommendations Yaron Sheffer
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Yaron Sheffer
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Michael D'Errico
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Patrick Pelletier
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Xuelei Fan
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Martin Rex
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Yaron Sheffer
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Yoav Nir
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Yaron Sheffer
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Martin Rex
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Blumenthal, Uri - 0558 - MITLL
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Blumenthal, Uri - 0558 - MITLL
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Yaron Sheffer
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Peter Gutmann
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Yaron Sheffer
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Peter Gutmann
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Yaron Sheffer
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Michael Ströder
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Yaron Sheffer
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Blumenthal, Uri - 0558 - MITLL
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… james hughes
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… james hughes
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Blumenthal, Uri - 0558 - MITLL
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Michael Ströder
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Michael Ströder
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… james hughes
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Blumenthal, Uri - 0558 - MITLL
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Yoav Nir
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Yaron Sheffer
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Bill Frantz
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Ralph Holz
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Martin Rex
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Martin Rex
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Martin Rex
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… james hughes
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Peter Gutmann
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Peter Gutmann
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Yaron Sheffer
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Michael Ströder
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Yaron Sheffer
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… james hughes
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Peter Gutmann
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Michael Ströder
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Michael D'Errico
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Yoav Nir
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Yaron Sheffer
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Yaron Sheffer
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Stephen Farrell
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Patrick Pelletier
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Yoav Nir
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Michael D'Errico
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Yaron Sheffer
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Yaron Sheffer
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Ralph Holz
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… james hughes
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Ralph Holz
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Nikos Mavrogiannopoulos
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Patrick Pelletier
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Patrick Pelletier
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Patrick Pelletier
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Yoav Nir
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Peter Gutmann
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Patrick Pelletier
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Martin Rex
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Peter Gutmann
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Yaron Sheffer
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Alex Elsayed
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Michael D'Errico
- Re: [TLS] draft-sheffer-tls-bcp: DH recommendatio… Peter Gutmann
- [TLS] Safe ECC usage D. J. Bernstein
- Re: [TLS] Safe ECC usage Dan Brown
- Re: [TLS] Safe ECC usage D. J. Bernstein
- Re: [TLS] Safe ECC usage Dan Brown
- Re: [TLS] Safe ECC usage Kyle Hamilton
- Re: [TLS] Safe ECC usage Johannes Merkle
- Re: [TLS] Safe ECC usage Adam Langley
- Re: [TLS] Safe ECC usage Santosh Chokhani
- Re: [TLS] Safe ECC usage Martin Rex
- Re: [TLS] Safe ECC usage Kyle Hamilton
- Re: [TLS] Safe ECC usage Yoav Nir
- Re: [TLS] Safe ECC usage Martin Rex
- Re: [TLS] Safe ECC usage D. J. Bernstein
- Re: [TLS] Safe ECC usage Dan Brown
- Re: [TLS] Safe ECC usage Johannes Merkle
- Re: [TLS] Safe ECC usage Manuel Pégourié-Gonnard
- Re: [TLS] Safe ECC usage Yoav Nir
- Re: [TLS] Safe ECC usage D. J. Bernstein
- Re: [TLS] Safe ECC usage Dan Brown
- Re: [TLS] Safe ECC usage D. J. Bernstein
- Re: [TLS] Safe ECC usage Dan Brown
- Re: [TLS] Safe ECC usage Johannes Merkle
- [TLS] (offline note) Re: Safe ECC usage Rene Struik
- Re: [TLS] Safe ECC usage D. J. Bernstein
- [TLS] (EC)DSA potential problems (ECC "brittlenes… Martin Rex
- Re: [TLS] Safe ECC usage Dan Brown
- Re: [TLS] Safe ECC usage D. J. Bernstein
- Re: [TLS] Safe ECC usage Dan Brown
- Re: [TLS] Safe ECC usage Watson Ladd
- Re: [TLS] Safe ECC usage Dan Brown
- Re: [TLS] Safe ECC usage Johannes Merkle
- Re: [TLS] Safe ECC usage Nico Williams
- Re: [TLS] Safe ECC usage Dan Brown
- Re: [TLS] Safe ECC usage Nico Williams
- Re: [TLS] Safe ECC usage Michael StJohns
- Re: [TLS] Safe ECC usage Dan Brown
- Re: [TLS] Safe ECC usage Nico Williams
- Re: [TLS] Safe ECC usage Bill Frantz
- Re: [TLS] Safe ECC usage D. J. Bernstein
- Re: [TLS] Safe ECC usage Dan Brown
- [TLS] DH group negotiation extension [was: Re: dr… Daniel Kahn Gillmor
- Re: [TLS] DH group negotiation extension [was: Re… Dang, Quynh
- Re: [TLS] DH group negotiation extension [was: Re… Patrick Pelletier
- Re: [TLS] DH group negotiation extension [was: Re… Watson Ladd