Re: [TLS] SCSV vs RI when both specified. Was: Updated draft

Steve Checkoway <s@pahtak.org> Sat, 19 December 2009 08:47 UTC

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Subject: Re: [TLS] SCSV vs RI when both specified. Was: Updated draft
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On Dec 18, 2009, at 1:02 PM, Michael D'Errico wrote:

> My two sentences describe everything you need to know:
>
>   SCSV absent,  RI absent:   hide the kids
>   SCSV absent,  RI present:  same as RI
>   SCSV present, RI absent:   same as empty RI
>   SCSV present, RI present:  same as RI (SCSV ignored)
>
> Why do you want the last one to be "ABORT!!"?


It's pretty clear (to me) that it doesn't matter if the last one is  
allowed or not, as long as the spec makes a clear decision. It's  
roughly the same amount of code (plus or minus a conditional and an  
alert). The four conditions have to be tested regardless of how it's  
defined.

Is this point really so important that it's worth holding up  
publication and subsequent implementation? I say it is not.

-- 
Steve Checkoway

     "Anyone who says that the solution is to educate the users
     hasn't ever met an actual user." -- Bruce Schneier