Re: NUL handling and security considerations [was: Re: My open issues with RFC3028bis]

Alexey Melnikov <alexey.melnikov@isode.com> Sat, 16 July 2005 14:13 UTC

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Date: Sat, 16 Jul 2005 15:13:37 +0100
From: Alexey Melnikov <alexey.melnikov@isode.com>
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To: Ned Freed <ned.freed@mrochek.com>
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Subject: Re: NUL handling and security considerations [was: Re: My open issues with RFC3028bis]
References: <E1Do7RW-0002QU-TU@nostromo.freenet-ag.de> <200507010537.j615bTST035402@lab.smi.sendmail.com> <20050701090227.GB10060@nostromo.freenet-ag.de> <200507020516.j625G1rE050221@lab.smi.sendmail.com> <01LQ54CXB1B000004T@mauve.mrochek.com>
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Ned Freed wrote:

>>>I may be stretching it too far here, but AFAIK, there are implementations
>>>that truncate strings, thus corrupting test results.  Trying to label them
>>>non-conforming probably won't succeed, but we should not silently ignore
>>>this problem.
>>>      
>>>
>>I guess there are two choices:
>>A) Require correct handling of NUL
>>B) Strongly prefer correct handling of NUL and warn about the dangers of
>>   not doing so in the security considerations
>>    
>>
>I have no major problem with A but I think B is a better choice. FWIW, the
>implementation I work on has no problem handling NULs, but I worry that
>this will make many other implementations non-conforming.
>
I suspect that Cyrus Sieve doesn't handle encoded NULs properly. So I 
would prefer B.