policyd-spf crashing with IndexError

[Erik de Castro Lopo]

The following from my /var/log/mail.info file:

Oct 20 13:00:24 xxxxxxx postfix/smtpd[13361]: connect from mx03.myitml.com[91.208.47.34]
Oct 20 13:00:25 xxxxxxx postfix/smtpd[13875]: disconnect from unknown[212.25.14.162]
Oct 20 13:00:25 xxxxxxx policyd-spf[13876]: Read line: "request=smtpd_access_policy"
Oct 20 13:00:25 xxxxxxx policyd-spf[13876]: Read line: "protocol_state=RCPT"
Oct 20 13:00:25 xxxxxxx policyd-spf[13876]: Read line: "protocol_name=ESMTP"
Oct 20 13:00:25 xxxxxxx policyd-spf[13876]: Read line: "client_address=91.208.47.34"
Oct 20 13:00:25 xxxxxxx policyd-spf[13876]: Read line: "client_name=mx03.myitml.com"
Oct 20 13:00:25 xxxxxxx policyd-spf[13876]: Read line: "reverse_client_name=mx03.myitml.com"
Oct 20 13:00:25 xxxxxxx policyd-spf[13876]: Read line: "helo_name=mx03.myitml.com"
Oct 20 13:00:25 xxxxxxx policyd-spf[13876]: Read line: "sender=MAILER-DAEMON"
Oct 20 13:00:25 xxxxxxx policyd-spf[13876]: Read line: "<email address hidden>"
Oct 20 13:00:25 xxxxxxx policyd-spf[13876]: Read line: "recipient_count=0"
Oct 20 13:00:25 xxxxxxx policyd-spf[13876]: Read line: "queue_id="
Oct 20 13:00:25 xxxxxxx policyd-spf[13876]: Read line: "instance=3431.4add19b9.a63db.0"
Oct 20 13:00:25 xxxxxxx policyd-spf[13876]: Read line: "size=4427"
Oct 20 13:00:25 xxxxxxx policyd-spf[13876]: Read line: "etrn_domain="
Oct 20 13:00:25 xxxxxxx policyd-spf[13876]: Read line: "stress="
Oct 20 13:00:25 xxxxxxx policyd-spf[13876]: Read line: "sasl_method="
Oct 20 13:00:25 xxxxxxx policyd-spf[13876]: Read line: "sasl_username="
Oct 20 13:00:25 xxxxxxx policyd-spf[13876]: Read line: "sasl_sender="
Oct 20 13:00:25 xxxxxxx policyd-spf[13876]: Read line: "ccert_subject="
Oct 20 13:00:25 xxxxxxx policyd-spf[13876]: Read line: "ccert_issuer="
Oct 20 13:00:25 xxxxxxx policyd-spf[13876]: Read line: "ccert_fingerprint="
Oct 20 13:00:25 xxxxxxx policyd-spf[13876]: Read line: "encryption_protocol="
Oct 20 13:00:25 xxxxxxx policyd-spf[13876]: Read line: "encryption_cipher="
Oct 20 13:00:25 xxxxxxx policyd-spf[13876]: Read line: "encryption_keysize=0"
Oct 20 13:00:25 xxxxxxx policyd-spf[13876]: Read line: ""
Oct 20 13:00:25 xxxxxxx policyd-spf[13876]: Found the end of entry
Oct 20 13:00:25 xxxxxxx policyd-spf[13876]: Config: {'Mail_From_reject': 'Fail', 'PermError_reject': 'False', 'HELO_reject': 'SPF_Not_Pass', 'defaultSeedOnly': 1, 'debugLevel': 4, 'skip_addresses': '127.0.0.0/8,::ffff:127.0.0.0//104,::1//128', 'TempError_Defer': 'False'}
Oct 20 13:00:26 xxxxxxx policyd-spf[13876]: spfcheck: pyspf result: "['None', '', 'helo']"
Oct 20 13:00:26 xxxxxxx policyd-spf[13876]: None; identity=helo; client-ip=91.208.47.34; helo=mx03.myitml.com; envelope-from=mailer-daemon; <email address hidden>
Oct 20 13:00:26 xxxxxxx policyd-spf[13876]: Traceback (most recent call last):
Oct 20 13:00:26 xxxxxxx policyd-spf[13876]: File "/usr/bin/policyd-spf", line 420, in <module>
Oct 20 13:00:26 xxxxxxx policyd-spf[13876]: instance_dict, configData)
Oct 20 13:00:26 xxxxxxx policyd-spf[13876]: File "/usr/bin/policyd-spf", line 343, in spfcheck
Oct 20 13:00:26 xxxxxxx policyd-spf[13876]: mfrom_resultpolicy, local = get_resultcodes(configData, 'mfrom')
Oct 20 13:00:26 xxxxxxx policyd-spf[13876]: File "/usr/bin/policyd-spf", line 122, in get_resultcodes
Oct 20 13:00:26 xxxxxxx policyd-spf[13876]: if spf.domainmatch(reject_domain_list, sender_domain[1]):
Oct 20 13:00:26 xxxxxxx policyd-spf[13876]: IndexError: list index out of range
Oct 20 13:00:26 xxxxxxx postfix/spawn[13484]: warning: command /usr/bin/python exit status 1
Oct 20 13:00:26 xxxxxxx postfix/smtpd[13361]: warning: premature end-of-input on private/spfpolicy while reading input attribute name

ProblemType: Bug
Architecture: amd64
DistroRelease: Ubuntu 9.04
Package: postfix-policyd-spf-python 0.7.1-1
PackageArchitecture: all
ProcEnviron:
 SHELL=/bin/bash
 PATH=(custom, user)
 LANG=en_AU.UTF-8
SourcePackage: pypolicyd-spf
Uname: Linux 2.6.28-15-generic x86_64

[Erik de Castro Lopo (erikd)]

The problem is This code:

    sender_domain = string.split(sender, '@', 1)
    if spf.domainmatch(reject_domain_list, sender_domain[1]):

If sender has no '@' character, sender_domain ends up as a single element list and trying to index it by [1] results in an IndexError exception.

A robust solution to this (available for python >= 2.5) is:

    sender_domain = sender.partition ('@')[2]
    if spf.domainmatch(reject_domain_list, sender_domain):

The parition method applied to the sender string is guaranteed to return a 3 element tuple of which the [2] indexing grabs the last element.

I've hacked the policy-spf script on my incoming mail gateway as above and its been running for 20 plus hours without a hitch.

[Scott Kitterman (kitterman)]

Oct 20 13:00:25 xxxxxxx policyd-spf[13876]: Read line: "sender=MAILER-DAEMON" is not a case I had considered. Thanks. I'm going to patch this for Karmic and then do a new upstream release with some other stuff shortly.

[Scott Kitterman (kitterman)]

Fix uploaded to Karmic. Thanks. Fixing the test suite took longer than everything else (not fun).

[Launchpad Janitor (janitor)]

This bug was fixed in the package pypolicyd-spf - 0.7.1-1ubuntu1

---------------
pypolicyd-spf (0.7.1-1ubuntu1) karmic; urgency=low

  * Add debian/patches/mailerdaemon-crash-fix.patch to fix crash when "@" is
    missing from the Mail From address (LP: #455991)
    - Patch thanks to Erik de Castro Lopo
  * Version python-dev depends to 2.5 and later since the patch uses a Python
    2.5 function

 -- Scott Kitterman <email address hidden> Wed, 21 Oct 2009 22:01:05 -0400