Home / server / Questions / 444507
In Process
Graeme Perrow
Asked: 2012-11-02 11:02:17 +0800 CST

How can I forward email to a perl script on Linux?

  • 772

I would like all mail sent to a particular alias on a Linux machine to be processed by a perl script but sendmail is giving me a "Service unavailable" error and I don't understand what I'm missing.

I created my handle_email.pl script (right now, this just prints its parameters to /tmp/email.txt) and added a symbolic link to it in /etc/smrsh.

Then I added this to /etc/aliases:

mailtest: |handle_email.pl

and ran newaliases afterwards. Note that I've also tried mailtest: |/etc/smrsh/handle_email.pl which gave the same results. I've also tried copying the actual script into /etc/smrsh rather than a link, same results again.

When I send mail to the mailtest alias, the file in /tmp never gets created, and I get this in /var/log/maillog:

Nov  1 14:43:59 localhost sendmail[24839]: qA1IhwHm024839: from=<xxx@xxx>, size=284, class=0, nrcpts=1, msgid=<[email protected]>, proto=ESMTP, daemon=MTA, relay=[10.7.160.180]
Nov  1 14:43:59 localhost smrsh: uid 8: attempt to use "handle_email.pl"
Nov  1 14:43:59 localhost sendmail[24850]: qA1IhwHm024839: to=|handle_email.pl, ctladdr=<mailtest@xxx> (8/0), delay=00:00:00, xdelay=00:00:00, mailer=prog, pri=30570, dsn=5.0.0, stat=Service unavailable
Nov  1 14:43:59 localhost sendmail[24850]: qA1IhwHm024839: qA1IhxHm024850: DSN: Service unavailable
Nov  1 14:44:00 localhost sendmail[24850]: qA1IhxHm024850: to=<xxx@xxx>, delay=00:00:01, xdelay=00:00:01, mailer=esmtp, pri=31594, relay=sy-int-mx.xxx. [<IP addr>], dsn=2.0.0, stat=Sent (qA1Ii4127508 Message accepted for delivery)

I get an email message describing the failure, which says:

The original message was received at Thu, 1 Nov 2012 14:58:16 -0400
from [<ip address>]

   ----- The following addresses had permanent fatal errors -----
|/etc/smrsh/handle_email.pl
    (reason: Service unavailable)
    (expanded from: <mailtest@xxx>)

   ----- Transcript of session follows -----
smrsh: "handle_email.pl" not available for sendmail programs
554 5.0.0 Service unavailable

Why will smrsh not execute my script?

Update: Answering questions in comments.

I've copied the script to /etc/smrsh and removed the link. The file permissions are 0700 (also tried 0755) and the first line is #!/usr/local/bin/perl which is correct. There is only one file in /etc/smrsh. The ls -l output:

[main:g:64] xxx:/etc/smrsh# ls -l
total 4
-rwx------. 1 root root 281 Nov  1 16:35 handle_email.pl
sendmail

3 Answers

  1. Try changing the permission of /etc/smrsh/handle_email.pl to 755 and I think you'll have more success. You might want to restart sendmail just to be sure things are properly initialized and configured.

    • 1

  2. smrsh can be finicky. In your example the script is owned by root. Try changing ownership to mail.

    • 0

  3. You need to add handle_email.pl into /etc/smrsh but also every program that is executed from handle_email.pl. So if you use echo in order to write /tmp/email.txt you also need to do:

    ln -s /bin/echo /etc/smrsh/echo

    Edit: So in your case you need to link /usr/bin/perl

    • -1