Re: [exim] header validation

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Author: Sergey Dorofeev
Date:  
To: Mike Brudenell
CC: exim-users
Subject: Re: [exim] header validation
Hello,

there is no additional software, just "verify = header_syntax" in acl_check_data.
If this syntax is really invalid, then I should consider it as flaw of libreoffice-users mailing list.

18 нояб. 2015 г. 15:22 пользователь Mike Brudenell <mike.brudenell@???> написал:
>
> Hi, Sergey -
>
> As far as I remember, the standard Exim installation doesn't do any checking of the "From:" headers. Instead it deals with the MAIL FROM and RCPT TO addresses in the SMTP envelope.
>
> So anything on your setup that's checking "From:" headers must have been added by yourself? If so then presumably there might be an error in those checks, not in Exim itself. Perhaps you could look out the lines in your Exim configuration file that implement such checks and share them here; someone might then be able to spot a mistake in them.
>
> However…
>
> The "From:" line you give as an example is
>
>> From: hdv@gmail <hdv.jadev@???>
>
>
> and appears not to be valid under RFC 5322. That specification says a "From:" line is defined as
>
>> from            =   "From:" mailbox-list CRLF
>
>
> where
>
>> mailbox-list    =   (mailbox *("," mailbox)) / obs-mbox-list
>>
>> mailbox         =   name-addr / addr-spec
>>
>> name-addr       =   [display-name] angle-addr
>>
>> display-name    =   phrase
>>
>> phrase          =   1*word / obs-phrase
>>
>> word            =   atom / quoted-string
>>
>> atom            =   [CFWS] 1*atext [CFWS]
>>
>> atext           =   ALPHA / DIGIT /    ; Printable US-ASCII
>>                        "!" / "#" /        ;  characters not including
>>                        "$" / "%" /        ;  specials.  Used for atoms.
>>                        "&" / "'" /
>>                        "*" / "+" /
>>                        "-" / "/" /
>>                        "=" / "?" /
>>                        "^" / "_" /
>>                        "`" / "{" /
>>                        "|" / "}" /
>>                        "~"
>
>
> In your sample the display-name field is hdv@gmail and includes an "@", but this is not a character listed as being valid for atext. Therefore the entire display-name string has to be enclosed within quotes.
>
> So actually there might not be a mistake in your validation rule at all! If I'm right about the "From:" header not being valid (can some confirm this?) then your rule is doing its job and rejecting it! 😊
>
> Cheers,
> Mike B-)
>
> On 17 November 2015 at 18:39, sergey <sergey@???> wrote:
>>
>> Hello
>>
>> I've started to receive bounce notices from libreoffice mailing lists
>> Log record
>> ===
>> 2015-11-17 18:42:19 1ZykGp-0003Le-Bx H=bilbo2.documentfoundation.org [2a01:4f8:190:3144::2].
>> X=TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256 F=<users+bounces-47461-sergey=fidoman.ru@???>.
>> rejected after DATA: malformed address: <hdv.jadev@???>\n may not follow hdv@gmail :.
>> failing address in "From:" header is: hdv@gmail <hdv.jadev@???>
>> ===
>>
>> Exim4 refuses mail when valid address is given in header but sender name is spelled as e-mail (contains '@')
>> If e-mail is given inside '<>', should then field where sender name must reside to check if it contains '@' or not?
>>
>>
>> --
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>
>
>
>
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