[asterisk-bugs] [Asterisk 0010487]: IMAP integration with MS Exchange crashes Asterisk-1.4.10.1

[noreply at bugs.digium.com]

A NOTE has been added to this issue. 
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http://bugs.digium.com/view.php?id=10487 
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Reported By:                ewilhelmsen
Assigned To:                putnopvut
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Project:                    Asterisk
Issue ID:                   10487
Category:                   Applications/app_voicemail
Reproducibility:            always
Severity:                   crash
Priority:                   normal
Status:                     feedback
Asterisk Version:           1.4.10.1  
SVN Branch (only for SVN checkouts, not tarball releases): N/A  
SVN Revision (number only!):  
Disclaimer on File?:        N/A 
Request Review:              
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Date Submitted:             08-17-2007 12:59 CDT
Last Modified:              09-10-2007 05:30 CDT
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Summary:                    IMAP integration with MS Exchange crashes
Asterisk-1.4.10.1
Description: 
When setting voicemail.conf to MS Exchange IMAP server I am able to record
a message and it will send to the users Exchange Inbox but when MS Exchange
sends an IMAP response to Asterisk it does not know the tagged response for
SEARCH and NOOP. After this Warning:

[Aug 17 10:59:19] WARNING[26191]: app_voicemail.c:8572 mm_log: IMAP
Warning: Unexpected tagged response: 0000003a OK SEARCH completed.
[Aug 17 10:59:19] WARNING[26204]: app_voicemail.c:8572 mm_log: IMAP
Warning: Unexpected tagged response: 0000003e OK NOOP
completed. 

Asterisk crashes and needs to be Ctrl-C to exit and restarted.
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---------------------------------------------------------------------- 
 rayjay - 09-10-07 05:30  
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Some feedback on the patch so far...

The good news is that I haven't had any crashes or need to restart
Asterisk since applying the patch yet (although it is still fairly early
days).  One thing I have noticed though is the locking between  mailbox
queries sometimes seems to last for several seconds - during which time no
signalling/debug occurs in my console.  

What I think is happening is that some of my mailboxes are fairly large
(100+ voice messages) and since Courier isn't the fastest mail system at
retrieving messages from larger mailboxes, the mail_search queries often
can take several seconds particularly if not cached by the mail file
system.

Is there a way of not locking everything up (including SIP signalling)
while awaiting a response from the mail system?  I am also doing MWI
queries regularly  which adds more mailbox 'queries' to the mix.  One other
thing that I noticed:  If you have a failed login between Asterisk and the
IMAP server, typically the IMAP server will 'sleep' for 5 seconds before
returning an authentication failure (I think this is standard practice with
IMAP servers to avoid dictionary attacks etc.)  When this auth failure
occurs Asterisk also seems to lock up and all other call attempts etc. seem
to hang waiting for the lock to release.  I think there might be a more
fundamental issue in using locking when relying on an external resource
like an IMAP mail server which may have long search times, failed auth
problems etc.

I realise this may have gone wildly off-topic.  If you think my
IMAP/locking concerns should be taken elsewhere then let me know.  For now
though your patch appears to be achieving *its* job of stopping the
crashes/hangs. 

Issue History 
Date Modified   Username       Field                    Change               
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09-10-07 05:30  rayjay         Note Added: 0070245                          
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