[Dovecot] Some questions about deliver

[Axel Luttgens]

While investigating Dovecot's deliver with Postfix, I encountered some  
behaviors making me wonder whether I really understand the purpose of  
that binary. So, if you allow...

This is from Postfix' main.cf:

     mailbox_command = /usr/local/dovecot/libexec/dovecot/deliver -e -n

This is my quick setup for Dovecot:

     # 1.2.rc4: /usr/local/etc/dovecot.conf
     # OS: Darwin 9.7.0 i386
     protocols: pop3
     ssl: no
     disable_plaintext_auth: no
     login_dir: /usr/local/var/run/dovecot/login
     login_executable: /usr/local/dovecot-1.2.rc4/libexec/dovecot/pop3- 
login
     first_valid_uid: 2001
     mail_location: mbox:~/_mailboxes:INBOX=~/_inbox/mailspool
     mbox_read_locks: flock
     mbox_write_locks: flock dotlock
     mail_executable: /usr/local/dovecot-1.2.rc4/libexec/dovecot/pop3
     mail_plugin_dir: /usr/local/dovecot-1.2.rc4/lib/dovecot/pop3
     pop3_lock_session: yes
     pop3_uidl_format: %08Xv%08Xu
     auth default:
       passdb:
         driver: pam
         args: *
       userdb:
         driver: passwd

Here is an excerpt from mail.log:

     postfix/smtpd[4117]: connect from localhost[127.0.0.1]
     postfix/smtpd[4117]: 163E1CA2675: client=localhost[127.0.0.1]
     postfix/cleanup[4120]: 163E1CA2675: message-id=<27002A3F-AF44-410D-A500-368D04F5FA9A at almbp.local 
 >
     postfix/qmgr[3232]: 163E1CA2675: from=<testuser at almbp.local>,  
size=2650, nrcpt=1 (queue active)
     dovecot[4129]: deliver(www): mail_location: mbox: mkdir(/Library/ 
WebServer/_mailboxes) failed: Permission denied (euid=70(_www)  
egid=70(_www) missing +w perm: /Library/WebServer)
     dovecot[4129]: deliver(www): Fatal: Namespace initialization failed
     postfix/local[4122]: 163E1CA2675: to=<www at almbp.local>,  
relay=local, delay=0.09, delays=0.02/0/0/0.07, dsn=4.3.0,  
status=deferred (temporary failure)
     postfix/smtpd[4117]: disconnect from localhost[127.0.0.1]


1. Shouldn't deliver honor the first_valid_uid setting?

After all, if some user isn't allowed to login, is that user supposed  
to receive mail?

2. What exactly is the -e option supposed to do?

User _www clearly isn't configured for receiving mail, but Postfix  
will nevertheless try to deliver the message until  
maximal_queue_lifetime has expired.
 From the log excerpt, it appears that Postfix has been led to  
consider a temporary failure; unless I'm wrong, that's because Postfix  
didn't receive neither a "D.S.N text" string nor an EX_* fatal return  
code.
 From deliver.c, it seems that many calls to i_fatal() are liable to  
be executed before the -e option is taken into account (through the  
local variable stderr_rejection).
As a result, I'm wondering under which circumstances exactly deliver  
is liable to return EX_NOPERM, so that Postfix may consider a  
permanent failure and bounce the message.

Note that the question may somehow be re-phrased as: when invoked  
without the -e option, under which circumstances will deliver send a  
rejection message?

3. Doesn't failure_exit_callback() in deliver.c tend to merge many  
(possibly dissimilar) errors into the single EX_TEMPFAIL one?

And BTW, is that function guaranteed to be always called with an EX_*  
value? Seems to be the case, but... ;-)


TIA for your patience,
Axel