Re: [TLS] RFC 4492 and HSM
Watson Ladd <watsonbladd@gmail.com> Tue, 22 April 2014 04:09 UTC
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Date: Mon, 21 Apr 2014 21:09:45 -0700
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From: Watson Ladd <watsonbladd@gmail.com>
To: Daniel Kahn Gillmor <dkg@fifthhorseman.net>
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Subject: Re: [TLS] RFC 4492 and HSM
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On Mon, Apr 21, 2014 at 9:07 PM, Daniel Kahn Gillmor <dkg@fifthhorseman.net> wrote: > On 04/21/2014 09:00 PM, Watson Ladd wrote: > >> RFC 4492 specifies an ECDSA signature of the server's curve parameters >> and ephemeral point, but not any fresh data. As a result the ephemeral >> exponent is equal in sensitivity to the long-term exponent of the >> ECDSA key, forcing an HSM to protect both, and thus do three >> exponentiations per connection. > > It looks to me like RFC 4492 specifies that the data signed includes > both the ClientHello.random and the ServerHello.random: > > https://tools.ietf.org/html/rfc4492#page-20 This is correct. I was confused because section 2.2 says the parameters are signed, but doesn't mention the fresh data. Ignore previous email. Sincerely, Watson Ladd -- "Those who would give up Essential Liberty to purchase a little Temporary Safety deserve neither Liberty nor Safety." -- Benjamin Franklin
- [TLS] RFC 4492 and HSM Watson Ladd
- Re: [TLS] RFC 4492 and HSM Daniel Kahn Gillmor
- Re: [TLS] RFC 4492 and HSM Watson Ladd