[horde] Sending HTTP 401 Unauthorized header response

[Michael J Rubinsky]

Quoting Arjen de Korte <build+horde at de-korte.org>:

> Citeren Arjen de Korte <build+horde at de-korte.org>:
>
>> Citeren Arjen de Korte <build+horde at de-korte.org>:
>>
>>> Possibly more log spam:
>>>
>>> 2019-01-04T13:23:44+01:00 ERR: horde Sending HTTP 401 Unauthorized  
>>> header response. [pid 1949 on line 126 of  
>>> "/usr/share/php7/PEAR/Horde/Rpc/ActiveSync.php"]
>>>
>>> Dumping $serverVars just a few lines before this line, it looks  
>>> like the client attempts to authenticate with type "Bearer" but  
>>> there is no token. I also see requests where the same client is  
>>> using Basic authentication with a base64 encoded username and  
>>> password, which works fine. The client in question is the built-in  
>>> Windows 10 Mail and synchronizes as usual.
>>>
>>> I've removed the account and recreated it, but the problem remains.
>>
>> It occurs with multiple accounts, all using the Windows 10 Mail  
>> client. When logging the $serverVars['HTTP_AUTHORIZATION']  
>> variable, they seem to come in pairs:
>>
>>    2019-01-04T19:24:10+01:00 DEBUG: Variable information:
>>    string(50) "Basic XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX=="
>>
>>    Backtrace:
>>    1. Horde_Rpc_ActiveSync->getResponse() /srv/www/htdocs/horde/rpc.php:160
>>    2. Horde::debug() /usr/share/php7/PEAR/Horde/Rpc/ActiveSync.php:120
>>
>>    2019-01-04T19:24:26+01:00 DEBUG: Variable information:
>>    string(6) "Bearer"
>>
>>    Backtrace:
>>    1. Horde_Rpc_ActiveSync->getResponse() /srv/www/htdocs/horde/rpc.php:160
>>    2. Horde::debug() /usr/share/php7/PEAR/Horde/Rpc/ActiveSync.php:120
>>
>> Could it somehow be that no token is sent from the server to the  
>> client? Can I somehow log the token?
>
> These are weird requests. I enabled the forensics log of Apache and  
> this is what it came up with for these packets:
>
> +24647:5c308a50:0|OPTIONS  
> /Microsoft-Server-ActiveSync?User=xxxx&DeviceId=XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX&DeviceType=WindowsMail HTTP/1.1|Cache-Control:no-cache|Connection:Keep-Alive|Pragma:no-cache|Authorization:Basic  
> XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX=|User-Agent:MSFT-WIN-3/10.0.17134|MS-ASProtocolVersion:14.1|Host:mail.example.com|Cookie:PHPSESSID=XXXXXXXXXXXXXXXXXXXXXXXXXX
> +24647:5c308b42:5|OPTIONS /Microsoft-Server-ActiveSync  
> HTTP/1.1|Cache-Control:no-cache|Connection:Keep-Alive|Pragma:no-cache|Authorization:Bearer|User-Agent:MSFT-WIN-3/10.0.17134|MS-ASProtocolVersion:2.5|Host:mail.example.com
>
> The first is what I expect for ActiveSync connections, but the  
> second looks like some kind of probe for the connectivity to the EAS  
> server, rather than an attempt to actively exchange data. Look at  
> the difference in the ASProtocolVersion and the absence of any  
> identifying data.

This looks like the initial, empty Bearer challenge that Outlook can  
send when initiating OAuth authentication. This is used when the  
client is enabled for Hybrid Modern Authentication. This is used when  
Outlook is connecting with Office 365/Azure AD in combination with a  
on-premise Exchange server. No clue why the client would send those  
frequently. If you are seeing those often, it sounds like a client bug.


>
> -- 
> Horde mailing list
> Frequently Asked Questions: http://horde.org/faq/
> To unsubscribe, mail: horde-unsubscribe at lists.horde.org



-- 
mike
The Horde Project
http://www.horde.org
https://www.facebook.com/hordeproject
https://www.twitter.com/hordeproject
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-keys
Size: 9272 bytes
Desc: PGP Public Key
URL: <https://lists.horde.org/archives/horde/attachments/20190105/6bdb5195/attachment.bin>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 821 bytes
Desc: PGP Digital Signature
URL: <https://lists.horde.org/archives/horde/attachments/20190105/6bdb5195/attachment-0001.bin>