The FreeBSD Diary

Sometimes you want mail to be received and fed into a program rather than be stored in a mailbox.   This is how I did that.

test@yourdomain.org  "|/usr/local/etc/freshports/mail-catcher.pl"

Then I did this from within /etc/mail:

makemap hash virtusertable < virtusertable    

But mail sent to the address resulted in this error:

Apr 18 17:22:12 ducky sendmail[10898]: RAA10898: 
     <test@yourdomain.org>... Cannot mail directly to programs    

First, I modified the entry from the previous section to be:

test@yourdomain.org  test-yourdomain-org

In this case, all mail for the above address will be handled by the alias test-yourdomain-org.   Then I did a makemap again as per above.  Now we will create the alias.

Next, I modified one of my majordomo alias files to contain this (you could try /etc/aliases):

test-yourdomain-org: "|/usr/local/etc/freshports/mail-catcher.pl"    

Then I ran newaliases to invoke the above definition.  Check your logs for any errors (perhaps /var/log/messages or /var/log/maillog).

Then I tried sending another test message.  Yet another error message:

/usr/local/etc/freshports/mail-catcher/mail-catcher.pl: not found 554
"|/usr/local/etc/freshports/mail-catcher/mail-catcher.pl"... 
unknown mailer error 127    

This was pretty easy to solve.  The script wasn't in the expected location.   So I moved the file to
/usr/local/etc/freshports/mail-catcher and tried again.  This time, I encountered this error:

/usr/local/etc/freshports/mail-catcher.pl: permission denied 554
"|/usr/local/etc/freshports/mail-catcher.pl"...
unknown mailer error 126

...which is almost, but not quite, the same error as I had above.

The long and the short of it is: I spent about 90 minutes trying to get this going.   Please see the next section for the details.

• sendmail will execute the script as the user daemon.  I figured this out by temporarily making the directory chmod 777 and seeing what user created the directory, then I changed the permissions.
• permissions on /usr/local/etc/freshports/ must allow daemon to read and execute the script.  I chose chmod 750 and chown dan:daemon
• I set the permissions on the script to be chmod 640 and chown dan:daemon

Here is what the directory looks like:

drwxr-x--- 3 dan daemon 512 Apr 18 20:12 freshports    

And the script:

-rwxr-x--- 1 dan daemon 830 Apr 18 20:10 mail-catcher.pl    

The script outputs data to a subdirectory msgs.  I chose this option for security reasons.  The goal was to restrict the directories to which daemon had write access.  I didn't want it to have write access to the directory in which the script existed, just in case.  Here are the attributes of the msgs directory:

drwxrwx---  2 dan   daemon   512 Apr 18 20:21 msgs    

Files in the above directory which were created by the script look like this:

-rw-r--r--  1 daemon  daemon  935 Apr 18 20:12 956045563.12488
-rw-r--r--  1 daemon  daemon  935 Apr 18 20:15 956045746.12546
-rw-r--r--  1 daemon  daemon  935 Apr 18 20:21 956046115.12604

Someone also mentioned creating a user, sending the mail to their normal mailbox, then use .forward to redirect the mail to the program.