Re: [TLS] What would make TLS cryptographically better for TLS 1.3
Johannes Merkle <johannes.merkle@secunet.com> Tue, 05 November 2013 13:19 UTC
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Date: Tue, 05 Nov 2013 14:18:49 +0100
From: Johannes Merkle <johannes.merkle@secunet.com>
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To: Ralf Skyper Kaiser <skyper@thc.org>, mrex@sap.com
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Cc: "tls@ietf.org" <tls@ietf.org>
Subject: Re: [TLS] What would make TLS cryptographically better for TLS 1.3
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Ralf Skyper Kaiser schrieb am 05.11.2013 03:03: > A securely configured TLS client would verify the certificate chain. > > The server has no way to check if the TLS client is configured securely. > The server blindly trusts the client that it is configured securely. That > does not scale. Users make mistakes. Users will connect to a service not > knowing that the connection is not secure (even over TLS) because they did > not configure the TLS correctly. I don't see the point. You are referring to a verification of the server's certificate by the client. When a client identifies a server, what is the benefit for the server to ensure that the client performs the identification in a proper way? If the verification is not done properly by the client, the client may be susceptible to impersonation attacks on the server side, i.e. may trust a malicious server pretending to be the honest server. If such a case occurs, i.e, if the client has connected to a malicious server, what were the point in the honest server's checking the client's policy? In such a case, the honest server is not even participating in the communication, and the malicious server, who is participating in the communication, will certainly not insist on a strict client policy (not if he is a clever attacker, at least). So, what threat scenario is your requirement (of the server being able to verify the client's policy) addressing? -- Johannes
- [TLS] What would make TLS cryptographically bette… Watson Ladd
- Re: [TLS] What would make TLS cryptographically b… Nico Williams
- Re: [TLS] What would make TLS cryptographically b… Dan Harkins
- Re: [TLS] What would make TLS cryptographically b… Nikos Mavrogiannopoulos
- Re: [TLS] What would make TLS cryptographically b… Robert Ransom
- Re: [TLS] What would make TLS cryptographically b… Nico Williams
- Re: [TLS] What would make TLS cryptographically b… Robert Ransom
- Re: [TLS] What would make TLS cryptographically b… Robert Ransom
- Re: [TLS] What would make TLS cryptographically b… Dan Harkins
- Re: [TLS] What would make TLS cryptographically b… Watson Ladd
- Re: [TLS] What would make TLS cryptographically b… Nico Williams
- Re: [TLS] What would make TLS cryptographically b… Robert Ransom
- Re: [TLS] What would make TLS cryptographically b… Nico Williams
- Re: [TLS] What would make TLS cryptographically b… Dan Harkins
- Re: [TLS] What would make TLS cryptographically b… Robert Ransom
- Re: [TLS] What would make TLS cryptographically b… Robert Ransom
- Re: [TLS] What would make TLS cryptographically b… Dan Harkins
- Re: [TLS] What would make TLS cryptographically b… Robert Ransom
- Re: [TLS] What would make TLS cryptographically b… Watson Ladd
- [TLS] removal of nonces [was: What would make TLS… Nikos Mavrogiannopoulos
- Re: [TLS] What would make TLS cryptographically b… Andy Lutomirski
- Re: [TLS] What would make TLS cryptographically b… Nico Williams
- Re: [TLS] removal of nonces [was: What would make… Nico Williams
- Re: [TLS] What would make TLS cryptographically b… Robert Ransom
- Re: [TLS] What would make TLS cryptographically b… Ralf Skyper Kaiser
- Re: [TLS] What would make TLS cryptographically b… Ralf Skyper Kaiser
- Re: [TLS] What would make TLS cryptographically b… Nikos Mavrogiannopoulos
- Re: [TLS] What would make TLS cryptographically b… Yoav Nir
- Re: [TLS] What would make TLS cryptographically b… Robert Ransom
- Re: [TLS] What would make TLS cryptographically b… Ralf Skyper Kaiser
- Re: [TLS] What would make TLS cryptographically b… Ralf Skyper Kaiser
- Re: [TLS] What would make TLS cryptographically b… Watson Ladd
- Re: [TLS] What would make TLS cryptographically b… Yoav Nir
- Re: [TLS] What would make TLS cryptographically b… Ralf Skyper Kaiser
- Re: [TLS] What would make TLS cryptographically b… Martin Rex
- Re: [TLS] What would make TLS cryptographically b… Ralf Skyper Kaiser
- Re: [TLS] What would make TLS cryptographically b… Jeff Jarmoc
- Re: [TLS] What would make TLS cryptographically b… Nico Williams
- Re: [TLS] What would make TLS cryptographically b… Yoav Nir
- Re: [TLS] What would make TLS cryptographically b… Johannes Merkle
- Re: [TLS] What would make TLS cryptographically b… Dan Harkins
- Re: [TLS] What would make TLS cryptographically b… Yoav Nir
- Re: [TLS] What would make TLS cryptographically b… Santosh Chokhani
- Re: [TLS] What would make TLS cryptographically b… Ralf Skyper Kaiser