Re: [ietf-smtp] Is this a valid Message-ID header ?

Conversion of all ASCII headers to utf-8 mime encoded should be banned. Apart
from testing encoding/decoding it serves no useful purpose and if you want
to perform such testing you can always add a non ASCII character.  MUA’s that
do this are deliberately breaking interoperability with old MUAs.

Mark

> On 6 Mar 2020, at 14:27, Valdis Klētnieks <valdis.kletnieks@vt.edu> wrote:
> 
> On 04 Mar 2020 23:34:13 -0500, "John Levine" said:
>> I read IETF mailing lists on the IETF's IMAP server* and of late I've been
>> seeing some awfully funky stuff.
>> 
>> This is an actual Message-ID header in one of the messages in dnsop.
>> Is that valid?  Even though the MIME decodes to a an ASCII message ID
>> in the <string@domain> format, I think the answer is no.  That's not
>> what RFC 5322 sec 3.6 allows.
> 
> I'll see your Message-ID, and raise you a... not even sure *what* to call it. :)
> 
>> From my collection of emails that give exmh indigestion:
> 
> % grep UTF-8 183
> From: =?UTF-8?B?dGlwLWJvdCBmb3IgRGF2aWQgQnJvd24gPHRpcGJvdEB6eXRvci5jb20+?=@zytor.com
> To: =?UTF-8?B?bGludXgtdGlwLWNvbW1pdHNAdmdlci5rZXJuZWwub3Jn?=@zytor.com
> Subject: =?UTF-8?B?W3RpcDptbS9yZWFkb25seV0gQVJNL3Zkc286IE1hcmsgdGhlIHZEU08gY29kZSA=?=  =?UTF-8?B?cmVhZC1vbmx5IGFmdGVyIGluaXQ=?=
> Git-Commit-ID: =?UTF-8?B?MTFiZjliODY1ODk4OTYxY2VlNjBhNDFjNDgzYzlmMjdlYzc2ZTEyZQ==?=
> X-Mailer: =?UTF-8?B?dGlwLWdpdC1sb2ctZGFlbW9u?=
> Robot-ID: =?UTF-8?B?PHRpcC1ib3QuZ2l0Lmtlcm5lbC5vcmc+?=
> Robot-Unsubscribe: =?UTF-8?B?Q29udGFjdCA8bWFpbHRvOmhwYUBrZXJuZWwub3JnPiB0byBnZXQgYmxhY2tsaXM=?=  =?UTF-8?B?dGVkIGZyb20gdGhlc2UgZW1haWxz?=
> MIME-Version: =?UTF-8?B?MS4w?=
> Content-Transfer-Encoding: =?UTF-8?B?OGJpdA==?=
> Content-Type: =?UTF-8?B?dGV4dC9wbGFpbjsgY2hhcnNldD1VVEYtOA==?=
> Content-Disposition: =?UTF-8?B?aW5saW5l?=
> 
> Amazingly enough, this managed to collect 10 Received: headers, land in my
> mailbox, and exmh *mostly* figured it out:
> 
> From: tip-bot for David Brown <tipbot@zytor.com>@zytor.com
> To: linux-tip-commits@vger.kernel.org@zytor.com
> Subject: [tip:mm/readonly] ARM/vdso: Mark the vDSO code   read-only after init
> Git-commit-id: 11bf9b865898961cee60a41c483c9f27ec76e12e
> X-mailer: tip-git-log-daemon
> Robot-id: <tip-bot.git.kernel.org>
> Robot-unsubscribe: Contact <mailto:hpa@kernel.org> to get blacklis  ted from these emails
> Mime-version: 1.0
> Content-transfer-encoding: 8bit
> Content-type: text/plain; charset=UTF-8
> Content-disposition: inline
> 
> But then finally gave up because it tried to use the undecoded content-type,
> gave up, and tossed up a "save/print/don't decode MIME" dialog.
> 
> And yes, tip-bot got fixed quite quickly thereafter... :)
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-- 
Mark Andrews, ISC
1 Seymour St., Dundas Valley, NSW 2117, Australia
PHONE: +61 2 9871 4742              INTERNET: marka@isc.org