Re: Last Call: <draft-nottingham-safe-hint-05.txt> (The "safe" HTTP Preference) to Proposed Standard

Doug Barton <dougb@dougbarton.us> Tue, 18 November 2014 17:55 UTC

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Date: Tue, 18 Nov 2014 09:54:58 -0800
From: Doug Barton <dougb@dougbarton.us>
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To: Mark Nottingham <mnot@mnot.net>, IETF <ietf@ietf.org>
Subject: Re: Last Call: <draft-nottingham-safe-hint-05.txt> (The "safe" HTTP Preference) to Proposed Standard
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On 11/17/14 9:16 PM, Mark Nottingham wrote:
> Reminder: if you want an e-mail response to a message on this list, please CC: me.
>
> Doug Barton said:
>
>> Mark, can you respond to this point in more detail? Specifically, given
>> that there are already more-granular cookie-based solutions which are
>> nearly universally deployed, how much does preventing granularity in the
>> initial signal to the site help avoid this pitfall?
>
> Because the hint is potentially sent on *all* requests, not just selected sites.

Thanks for the response. I'm not sure I find it compelling though. :-/ 
There are (roughly) three types of web sites, ones that will ignore the 
flag completely, ones that will honor it as the user intended, and ones 
that will attempt to use the information to data-mine beyond what the 
user intended. The first two we can ignore, it's the last type that's of 
concern, yes?

So what's to stop that malicious site owner from putting up a block on 
their site unless you fill out the form that tells them the PII they 
want to know? (Hint: nothing, they already do that) So either the whole 
idea of the flag is dangerous because it may reveal something to a 
malicious site that the user would not want revealed, or the idea is 
useful, and one bit is not enough granularity to make it truly compelling.

Doug