Script for checking the DMARC, SPF parts of a domain DNS record.
Uses python library checkdmarc, which works when provided with a name server.
SPF breakdown text taken from dmarcian.com.
First, own the libs:
pip3 install checkdmarc tabulate
usage: mail_check.py [-h] [-d D] [-l L] [-f]
Mail record checking utility
optional arguments:
-h, --help show this help message and exit
-d D The domain record to test
-l L File of domains to test, one domain per line
-f Run all testsRun with "-d" and the domain to do a DMARC and SPF check:
> python3 mail_check.py -d 6point6.co.uk
Pure domain = "6point6.co.uk"
==== DMARC ====
Field Value
---------- -------------------------------------------------------------------------------------------------------
Location 6point6.co.uk
Version DMARC1
Raw Record v=DMARC1; p=quarantine; rua=mailto:55d7175f07@rep.dmarcanalyzer.com; pct=100; sp=none; adkim=r; aspf=r;
Fields:
+-------+-------------+--------------------------------------------+------------------------------------------------------------------+
| Key | Set | Value | Comment |
+=======+=============+============================================+==================================================================+
| p | True | quarantine | Mail failing the DMARC authentication and alignment |
| | | | checks be treated as suspicious by mail receivers. |
| | | | This can mean receivers place the email in the spam/junk folder, |
| | | | flag as it suspicious |
| | | | or scrutinize this mail with extra intensity. |
+-------+-------------+--------------------------------------------+------------------------------------------------------------------+
| adkim | True | r | Relaxed Mode allows Authenticated DKIM/SPF domains |
| | | | that share a common Organizational Domain |
| | | | with an email's "header-From:" |
| | | | domain to pass the DMARC check. |
+-------+-------------+--------------------------------------------+------------------------------------------------------------------+
| aspf | True | r | Relaxed Mode allows Authenticated DKIM/SPF domains |
| | | | that share a common Organizational Domain |
| | | | with an email's "header-From:" |
| | | | domain to pass the DMARC check. |
+-------+-------------+--------------------------------------------+------------------------------------------------------------------+
| rua | True | Address: 55d7175f07@rep.dmarcanalyzer.com, | Indicates where aggregate DMARC reports should be sent to. |
| | | scheme: mailto | |
+-------+-------------+--------------------------------------------+------------------------------------------------------------------+
| ruf | Not Defined | Not Defined | Indicates where forensic DMARC reports should be sent to. |
+-------+-------------+--------------------------------------------+------------------------------------------------------------------+
| pc | True | 100 | Percentage of messages to which the |
| | | | DMARC policy is to be applied. |
| | | | This parameter provides a way to gradually |
| | | | implement and test the impact of the policy. |
+-------+-------------+--------------------------------------------+------------------------------------------------------------------+
| sp | True | none | (Sub-Domains) No specific action be taken on mail |
| | | | that fails DMARC authentication and alignment. |
+-------+-------------+--------------------------------------------+------------------------------------------------------------------+
| fo | False | 0 | Generate a DMARC failure report if all |
| | | | underlying authentication mechanisms |
| | | | fail to produce an aligned “pass” result. (Default) |
+-------+-------------+--------------------------------------------+------------------------------------------------------------------+
| rf | False | afrf | The reporting format for individual Forensic reports. |
| | | | Authorized values: “afrf”, “iodef”. |
+-------+-------------+--------------------------------------------+------------------------------------------------------------------+
| ri | False | 86400 | The number of seconds elapsed between |
| | | | sending aggregate reports to the sender. |
| | | | The default value is 86,400 seconds or a day. |
+-------+-------------+--------------------------------------------+------------------------------------------------------------------+
==== SPF ====
Raw SPF Record: v=spf1 include:servers.mcsv.net include:_spf.google.com include:servers.outfunnel.com ~all
Details:
Version: v=spf1
~all means soft fail mail that doesn't match a rule - accept but tag
Included senders:
+-------------------+-----------------------+-------------+
| Type | Value | Detail |
+===================+=======================+=============+
| Known mail server | servers.mcsv.net | Mailchimp |
+-------------------+-----------------------+-------------+
| Known mail server | _spf.google.com | Google Mail |
+-------------------+-----------------------+-------------+
| Known mail server | servers.outfunnel.com | OutFunnel |
+-------------------+-----------------------+-------------+
Excluded senders:
None
The "-f" option gives full results, which include host records:
> python3 mail_check.py -d 6point6.co.uk
Pure domain = "6point6.co.uk"
==== DMARC ====
Field Value
---------- -------------------------------------------------------------------------------------------------------
Location 6point6.co.uk
Version DMARC1
Raw Record v=DMARC1; p=quarantine; rua=mailto:55d7175f07@rep.dmarcanalyzer.com; pct=100; sp=none; adkim=r; aspf=r;
Fields:
+-------+-------------+--------------------------------------------+------------------------------------------------------------------+
| Key | Set | Value | Comment |
+=======+=============+============================================+==================================================================+
| p | True | quarantine | Mail failing the DMARC authentication and alignment |
| | | | checks be treated as suspicious by mail receivers. |
| | | | This can mean receivers place the email in the spam/junk folder, |
| | | | flag as it suspicious |
| | | | or scrutinize this mail with extra intensity. |
+-------+-------------+--------------------------------------------+------------------------------------------------------------------+
| adkim | True | r | Relaxed Mode allows Authenticated DKIM/SPF domains |
| | | | that share a common Organizational Domain |
| | | | with an email's "header-From:" |
| | | | domain to pass the DMARC check. |
+-------+-------------+--------------------------------------------+------------------------------------------------------------------+
| aspf | True | r | Relaxed Mode allows Authenticated DKIM/SPF domains |
| | | | that share a common Organizational Domain |
| | | | with an email's "header-From:" |
| | | | domain to pass the DMARC check. |
+-------+-------------+--------------------------------------------+------------------------------------------------------------------+
| rua | True | Address: 55d7175f07@rep.dmarcanalyzer.com, | Indicates where aggregate DMARC reports should be sent to. |
| | | scheme: mailto | |
+-------+-------------+--------------------------------------------+------------------------------------------------------------------+
| ruf | Not Defined | Not Defined | Indicates where forensic DMARC reports should be sent to. |
+-------+-------------+--------------------------------------------+------------------------------------------------------------------+
| pc | True | 100 | Percentage of messages to which the |
| | | | DMARC policy is to be applied. |
| | | | This parameter provides a way to gradually |
| | | | implement and test the impact of the policy. |
+-------+-------------+--------------------------------------------+------------------------------------------------------------------+
| sp | True | none | (Sub-Domains) No specific action be taken on mail |
| | | | that fails DMARC authentication and alignment. |
+-------+-------------+--------------------------------------------+------------------------------------------------------------------+
| fo | False | 0 | Generate a DMARC failure report if all |
| | | | underlying authentication mechanisms |
| | | | fail to produce an aligned “pass” result. (Default) |
+-------+-------------+--------------------------------------------+------------------------------------------------------------------+
| rf | False | afrf | The reporting format for individual Forensic reports. |
| | | | Authorized values: “afrf”, “iodef”. |
+-------+-------------+--------------------------------------------+------------------------------------------------------------------+
| ri | False | 86400 | The number of seconds elapsed between |
| | | | sending aggregate reports to the sender. |
| | | | The default value is 86,400 seconds or a day. |
+-------+-------------+--------------------------------------------+------------------------------------------------------------------+
==== SPF ====
Raw SPF Record: v=spf1 include:servers.mcsv.net include:_spf.google.com include:servers.outfunnel.com ~all
Details:
Version: v=spf1
~all means soft fail mail that doesn't match a rule - accept but tag
Included senders:
+-------------------+-----------------------+-------------+
| Type | Value | Detail |
+===================+=======================+=============+
| Known mail server | servers.mcsv.net | Mailchimp |
+-------------------+-----------------------+-------------+
| Known mail server | _spf.google.com | Google Mail |
+-------------------+-----------------------+-------------+
| Known mail server | servers.outfunnel.com | OutFunnel |
+-------------------+-----------------------+-------------+
Excluded senders:
None
==== Hosts ====
Hostname: aspmx.l.google.com, preference: 10, TLS: True, starttls: True.
Addresses: 2a00:1450:400c:c07::1b, 64.233.184.27,
Hostname: alt1.aspmx.l.google.com, preference: 20, TLS: True, starttls: True.
Addresses: 209.85.233.26, 2a00:1450:4010:c03::1b,
Hostname: alt2.aspmx.l.google.com, preference: 20, TLS: True, starttls: True.
Addresses: 142.250.4.27, 2404:6800:4003:c06::1a,
Hostname: aspmx2.googlemail.com, preference: 30, TLS: True, starttls: True.
Addresses: 209.85.233.26, 2a00:1450:4010:c03::1b,
Hostname: aspmx3.googlemail.com, preference: 40, TLS: True, starttls: True.
Addresses: 142.250.4.27, 2404:6800:4003:c06::1a,
Warning: 142.250.4.27 does not have any reverse DNS (PTR) records
Warning: 2404:6800:4003:c06::1a does not have any reverse DNS (PTR) records
Warning: 142.250.4.27 does not have any reverse DNS (PTR) records
Warning: 2404:6800:4003:c06::1a does not have any reverse DNS (PTR) records