Re: [TLS] NULL cipher to become a MUST NOT in UTA BCP
Ralph Holz <holz@net.in.tum.de> Wed, 03 September 2014 18:00 UTC
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Date: Wed, 03 Sep 2014 20:00:43 +0200
From: Ralph Holz <holz@net.in.tum.de>
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Subject: Re: [TLS] NULL cipher to become a MUST NOT in UTA BCP
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>> That will make it clear that implementers are free to retain NULL (and >> they will), but that the purpose of the BCP is to propose secure TLS >> configurations to protect application-layer protocols, and for those no >> deployment should ever negotiate NULL. > > This is still too strong. Local MTA to Mail-Store LMTP is an > application protocol. It is a fine use-case for NULL ciphers. I hear you (and the others), but balancing the purpose of the BCP with such requirements as you mention leads me to believe we should favour the solution I proposed. I added one more thing, though: "Note: TLS implementations MAY retain code for the NULL cipher to allow specialised purposes like debugging, custom solutions, etc." That "custom solution" - to me - seems to address what you describe. I see no other way to balance the requirements. If the vote were black/white between dropping and keeping, I'd favour dropping, by the way. I'd rather protect the many. Ralph -- Ralph Holz I8 - Network Architectures and Services Technische Universität München http://www.net.in.tum.de/de/mitarbeiter/holz/ Phone +49.89.289.18043 PGP: A805 D19C E23E 6BBB E0C4 86DC 520E 0C83 69B0 03EF
- [TLS] NULL cipher to become a MUST NOT in UTA BCP Ralph Holz
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Blumenthal, Uri - 0558 - MITLL
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Viktor Dukhovni
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Paul Hoffman
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Salz, Rich
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Viktor Dukhovni
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Blumenthal, Uri - 0558 - MITLL
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Ralph Holz
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Ralph Holz
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Viktor Dukhovni
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Viktor Dukhovni
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Paul Lambert
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Bodo Moeller
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Blumenthal, Uri - 0558 - MITLL
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Nico Williams
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Nikos Mavrogiannopoulos
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Yutaka OIWA
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Blumenthal, Uri - 0558 - MITLL
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Ralph Holz
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Viktor Dukhovni
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Ralph Holz
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Blumenthal, Uri - 0668 - MITLL
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Viktor Dukhovni
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Geoffrey Keating
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Blumenthal, Uri - 0668 - MITLL
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Ralph Holz
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Ralph Holz
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Nico Williams
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Ralph Holz
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Nico Williams
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Ralph Holz
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Nico Williams
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Ralph Holz
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Blumenthal, Uri - 0668 - MITLL
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Ralph Holz
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Blumenthal, Uri - 0558 - MITLL
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Yutaka OIWA
- [TLS] uta-tls-bcp-02 thoughts (was: NULL cipher t… Viktor Dukhovni
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Bodo Moeller
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Yutaka OIWA
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Nico Williams
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Blumenthal, Uri - 0558 - MITLL
- Re: [TLS] uta-tls-bcp-02 thoughts (was: NULL ciph… Blumenthal, Uri - 0558 - MITLL
- Re: [TLS] uta-tls-bcp-02 thoughts (was: NULL ciph… Nico Williams
- Re: [TLS] uta-tls-bcp-02 thoughts (was: NULL ciph… Blumenthal, Uri - 0558 - MITLL
- Re: [TLS] uta-tls-bcp-02 thoughts Ralph Holz
- Re: [TLS] uta-tls-bcp-02 thoughts Blumenthal, Uri - 0558 - MITLL
- Re: [TLS] uta-tls-bcp-02 thoughts Ralph Holz
- Re: [TLS] uta-tls-bcp-02 thoughts (was: NULL ciph… Barry Leiba
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Bill Frantz
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Daniel Kahn Gillmor
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Bodo Moeller
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Ralph Holz
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Manuel Pégourié-Gonnard
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Viktor Dukhovni
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Manuel Pégourié-Gonnard
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Ralph Holz
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Ilari Liusvaara
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Nico Williams
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Blumenthal, Uri - 0668 - MITLL
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Ralph Holz
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Bodo Moeller
- Re: [TLS] NULL cipher to become a MUST NOT in UTA… Viktor Dukhovni