[stir] stir-06: JWT vs UAC time

Eric Burger <eburger@standardstrack.com> Fri, 11 December 2015 05:54 UTC

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From: Eric Burger <eburger@standardstrack.com>
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Subject: [stir] stir-06: JWT vs UAC time
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Section 7 defines the issued at JWT value (iat) as the time the UAC asserts in the SIP message:
      Third, the JSON key "iat" followed by a colon and then a quoted
      encoding of the value of the SIP Date header field [EB1] as a JSON
      NumericDate (as UNIX time, per [RFC7519] Section 2)/

Do we really want to do that? I think there is value in either the authenticator barfing if the SIP time is too old or the validator barfing because the SIP time is way different than the authenticator issued time. I do not like the idea of the validator lying on behalf of the UAC.