dovecot - Jun 2013 - Calling dovecot-lda from within Antispam pipe script (bash) seems to have no effect

Hello,

I'm attempting to configure the Dovecot Antispam plug-in on Ubuntu 12.04
LTS with Dovecot 2.0.19.

Everything seems to be in order with one considerable exception: when my
pipe script (a simple Bash shell script) calls the dovecot-lda
executable, absolutely nothing seems to result.

If I copy/paste the exact same command into the terminal, the mail is
delivered to the target mailbox, as expected.

Here's my pipe script: http://pastebin.com/DBXAZqsN

When I move a message from INBOX -> Junk, or from Junk -> INBOX, the
pipe script is called, and here's the output:

---------------------------------------------------------------
31465-start (--debug --username=amavis --ham)
Checking if the command-line input argument string (--debug
--username=amavis --ham) contains the string "ham" or "spam"
Mode is "HAM"
Calling (as user vmail) '/usr/lib/dovecot/deliver -d
"sa-training at example.com" -m "Training.HAM" -p
"/tmp/sendmail-msg-31465.txt"'
31465-end
---------------------------------------------------------------

But, for some reason, the call to "/usr/lib/dovecot/deliver"
doesn't
seem to do anything.

If I copy the above output and paste it into the terminal:

/usr/lib/dovecot/deliver -d "sa-training at example.com" -m
"Training.HAM"
-p "/tmp/sendmail-msg-31465.txt"

Dovecot does indeed deliver the message. This works whether I execute
the above command as "root" or "vmail".

Why does this command have no effect when called from within the pipe
script?

Here is my "doveconf -n" output:

# 2.0.19: /etc/dovecot/dovecot.conf
# OS: Linux 2.6.32-042stab076.8 x86_64 Ubuntu 12.04.2 LTS
auth_mechanisms = plain login
disable_plaintext_auth = no
listen = *,[::]
log_timestamp = "%Y-%m-%d %H:%M:%S "
mail_privileged_group = vmail
passdb {
  args = /etc/dovecot/dovecot-sql.conf
  driver = sql
}
plugin {
  antispam_backend = pipe
  antispam_debug_target = syslog
  antispam_pipe_program = /usr/bin/sa-learn-pipe.sh
  antispam_pipe_program_args = --debug;--username=amavis
  antispam_pipe_program_notspam_arg = --ham
  antispam_pipe_program_spam_arg = --spam
  antispam_pipe_tmpdir = /tmp
  antispam_spam_pattern_ignorecase = SPAM;JUNK
  antispam_trash_pattern_ignorecase = trash;Deleted *
  antispam_verbose_debug = 1
  quota = dict:user::file:/var/vmail/%d/%n/.quotausage
  quota_rule2 = Trash:storage=+100M
  quota_rule3 = Junk:ignore
  quota_warning = storage=95%% quota-warning 95 %u %d
  quota_warning2 = storage=80%% quota-warning 80 %u %d
  quota_warning3 = -storage=100%% quota-below below %u %d
  sieve = /var/vmail/%d/%n/.sieve
}
protocols = imap pop3
service auth {
  unix_listener /var/spool/postfix/private/auth {
    group = postfix
    mode = 0660
    user = postfix
  }
  unix_listener auth-userdb {
    group = vmail
    mode = 0600
    user = vmail
  }
  user = root
}
service quota-below {
  executable = script /usr/local/bin/quota-below.sh
  user = vmail
}
service quota-warning {
  executable = script /usr/local/bin/quota-warning.sh
  user = vmail
}
ssl_cert = </etc/postfix/smtpd.cert
ssl_key = </etc/postfix/smtpd.key
userdb {
  args = /etc/dovecot/dovecot-sql.conf
  driver = sql
}
protocol imap {
  mail_plugins = quota imap_quota antispam
}
protocol pop3 {
  mail_plugins = quota
  pop3_uidl_format = %08Xu%08Xv
}
protocol lda {
  info_log_path = /var/log/dovecot-lda.log
  log_path = /var/log/dovecot-lda-errors.log
  mail_plugins = sieve quota
}


Thank you,

-Ben

Hi Ben,

I checked over your script, and I don't see the problem either.  You
already checked everything that comes to my mind.

Maybe using something like set -e to try and get some output from the
script?  

-- 
Computerisms
Bob Miller      
867-334-7117 / 867-633-3760
http://computerisms.ca


On Wed, 2013-06-19 at 14:52 -0400, Ben Johnson wrote:
> Hello,
> 
> I'm attempting to configure the Dovecot Antispam plug-in on Ubuntu
12.04
> LTS with Dovecot 2.0.19.
> 
> Everything seems to be in order with one considerable exception: when my
> pipe script (a simple Bash shell script) calls the dovecot-lda
> executable, absolutely nothing seems to result.
> 
> If I copy/paste the exact same command into the terminal, the mail is
> delivered to the target mailbox, as expected.
> 
> Here's my pipe script: http://pastebin.com/DBXAZqsN
> 
> When I move a message from INBOX -> Junk, or from Junk -> INBOX, the
> pipe script is called, and here's the output:
> 
> ---------------------------------------------------------------
> 31465-start (--debug --username=amavis --ham)
> Checking if the command-line input argument string (--debug
> --username=amavis --ham) contains the string "ham" or
"spam"
> Mode is "HAM"
> Calling (as user vmail) '/usr/lib/dovecot/deliver -d
> "sa-training at example.com" -m "Training.HAM" -p
> "/tmp/sendmail-msg-31465.txt"'
> 31465-end
> ---------------------------------------------------------------
> 
> But, for some reason, the call to "/usr/lib/dovecot/deliver"
doesn't
> seem to do anything.
> 
> If I copy the above output and paste it into the terminal:
> 
> /usr/lib/dovecot/deliver -d "sa-training at example.com" -m
"Training.HAM"
> -p "/tmp/sendmail-msg-31465.txt"
> 
> Dovecot does indeed deliver the message. This works whether I execute
> the above command as "root" or "vmail".
> 
> Why does this command have no effect when called from within the pipe
> script?
> 
> Here is my "doveconf -n" output:
> 
> # 2.0.19: /etc/dovecot/dovecot.conf
> # OS: Linux 2.6.32-042stab076.8 x86_64 Ubuntu 12.04.2 LTS
> auth_mechanisms = plain login
> disable_plaintext_auth = no
> listen = *,[::]
> log_timestamp = "%Y-%m-%d %H:%M:%S "
> mail_privileged_group = vmail
> passdb {
>   args = /etc/dovecot/dovecot-sql.conf
>   driver = sql
> }
> plugin {
>   antispam_backend = pipe
>   antispam_debug_target = syslog
>   antispam_pipe_program = /usr/bin/sa-learn-pipe.sh
>   antispam_pipe_program_args = --debug;--username=amavis
>   antispam_pipe_program_notspam_arg = --ham
>   antispam_pipe_program_spam_arg = --spam
>   antispam_pipe_tmpdir = /tmp
>   antispam_spam_pattern_ignorecase = SPAM;JUNK
>   antispam_trash_pattern_ignorecase = trash;Deleted *
>   antispam_verbose_debug = 1
>   quota = dict:user::file:/var/vmail/%d/%n/.quotausage
>   quota_rule2 = Trash:storage=+100M
>   quota_rule3 = Junk:ignore
>   quota_warning = storage=95%% quota-warning 95 %u %d
>   quota_warning2 = storage=80%% quota-warning 80 %u %d
>   quota_warning3 = -storage=100%% quota-below below %u %d
>   sieve = /var/vmail/%d/%n/.sieve
> }
> protocols = imap pop3
> service auth {
>   unix_listener /var/spool/postfix/private/auth {
>     group = postfix
>     mode = 0660
>     user = postfix
>   }
>   unix_listener auth-userdb {
>     group = vmail
>     mode = 0600
>     user = vmail
>   }
>   user = root
> }
> service quota-below {
>   executable = script /usr/local/bin/quota-below.sh
>   user = vmail
> }
> service quota-warning {
>   executable = script /usr/local/bin/quota-warning.sh
>   user = vmail
> }
> ssl_cert = </etc/postfix/smtpd.cert
> ssl_key = </etc/postfix/smtpd.key
> userdb {
>   args = /etc/dovecot/dovecot-sql.conf
>   driver = sql
> }
> protocol imap {
>   mail_plugins = quota imap_quota antispam
> }
> protocol pop3 {
>   mail_plugins = quota
>   pop3_uidl_format = %08Xu%08Xv
> }
> protocol lda {
>   info_log_path = /var/log/dovecot-lda.log
>   log_path = /var/log/dovecot-lda-errors.log
>   mail_plugins = sieve quota
> }
> 
> 
> Thank you,
> 
> -Ben

Ben Johnson writes:
> It really boils-down to the fact that I can call the following on the
> command-line and it functions as expected:
>
> su vmail -c '/usr/lib/dovecot/deliver -a "sa-training at
example.com" -d
> "sa-training at example.com" -m "Training.SPAM" -p
> "/tmp/sendmail-msg-25794.txt"'
>
> Yet, when I attempt to do the exact same thing from within the pipe
> script that Dovecot Antispam calls, I receive exit code 75 from
> deliver/dovecot-lda and absolutely nothing is logged, with exception of
> the information of which I'm already aware (logged to syslog).
Have you also checked the environment variables?  I think dovecot-lda
gets some information from them.  Also, it's possible the PATH or some
other critical environment variables is different, causing the
difference in outcome.

Joseph Tam <jtam.home at gmail.com>

Ben Johnson <ben at indietorrent.org> writes:
> I added debugging output to the script, which now prints the environment
> variables. My script now outputs the following:
> ...
> CONFIG_FILE=/var/run/dovecot/config
> ...
> Does anything jump-out at you?
You didn't provide the analogous output from the interactive shell to
see the differences (for example, USER might be being used), but from
your later strace, I guess CONFIG_FILE has something to do with it.

These threads seems relevant

 	http://www.dovecot.org/list/dovecot/2011-May/059127.html
 	http://www.mail-archive.com/dovecot at dovecot.org/msg38349.html

That thread poster solved his problem by commenting out

 	service imap-postlogin {
 	# user = $default_internal_user
 	...
 	}

but I have no idea if it works, or whether it's a good idea, for your
case.  More docs

 	http://wiki2.dovecot.org/PostLoginScripting

Joseph Tam <jtam.home at gmail.com>