Tag: Opendkim

Debian SID Opendmarc Installation and Configuration

November 20, 2016
LinuxOpendmarc
0 Comment

In this post i will capture the installation of opendmarc and how its configure alongside Opendkim.

Install opendmarc

apt-get install opendmarc

Configure systemd service file

cat > /lib/systemd/system/opendkim.service <<EOT
[Unit]
Description=OpenDMARC Milter
Documentation=man:opendmarc(8) man:opendmarc.conf(5)
After=network.target nss-lookup.target 

[Service]
EnvironmentFile=/etc/default/opendmarc
Type=forking
PIDFile=/var/run/opendmarc/opendmarc.pid
User=opendmarc
ExecStart=/usr/sbin/opendkim -p $SOCKET -x /etc/opendmarc.conf -u opendmarc -P /var/run/opendmarc/opendmarc.pid
Restart=on-failure
ExecReload=/bin/kill -USR1 $MAINPID

[Install]
WantedBy=multi-user.target
EOT

The specific changes here are lines #9 EnvironmentFile #13 -p $SOCKET

Defaults File

cat > /etc/default/opendmarc <<EOT
SOCKET="inet:12302@localhost"
EOT

Opendmarc Config file

cat > /etc/opendmarc.conf <<EOT
AuthservID example.com
PidFile /var/run/opendmarc.pid
#RejectFailures false
Syslog true
SyslogFacility mail
UMask 0002
UserID opendmarc:opendmarc
TemporaryDirectory /tmp
AutoRestart true
EOT

Modify Postfix milters
If you are running both opendkim and opendmarc your milters will look like this:

non_smtpd_milters = inet:127.0.0.1:12301, inet:127.0.0.1:12302
smtpd_milters = inet:127.0.0.1:12301, inet:127.0.0.1:12302

Restart the service

systemctl daemon-reload
systemctl restart opendmarc
systemctl restart postfix

DNS

Now go modify your DNS, adding a TXT record ‘_dmarc‘with the value ‘v=DMARC1; p=none; rua=mailto:postmaster@example.com‘

When you have validated dmarc is working properly you can change p=none to p=reject

How can you validate it?

There are a number of tools online to help you with this, also you open up a mail in google and click ‘show original’.

screenshot_2016-11-20_12-32-23
 

Enjoy

Other resources
https://www.google.com/search?q=opendkim+setup

https://www.google.com/search?q=opendmarc+setup

 

Debian SID Opendkim Installation and Configuration Woes

November 19, 2016
LinuxOpendkim
0 Comment

TL;DR Opendkim. Hats off the to folk who do marvelous packing 99.99999% percent of the time.

But sometimes they just get it wrong or at least all documentation regarding the package, does not match up with the behavior the packager intended.
That said, hopefully i will help solve some of these issues here.

I assume you have postfix already working and you are just looking to add dkim support.

Install opendkim

apt-get install opendkim opendkim-tools

Configure systemd service file

cat > /lib/systemd/system/opendkim.service <<EOT
[Unit]
Description=OpenDKIM DomainKeys Identified Mail (DKIM) Milter
Documentation=man:opendkim(8) man:opendkim.conf(5) man:opendkim-genkey(8) man:opendkim-genzone(8) man:opendkim-testadsp(8) man:opendkim-testkey http://www.opendkim.org/docs.html
After=network.target nss-lookup.target 

[Service]
EnvironmentFile=/etc/default/opendkim
Type=forking
PIDFile=/var/run/opendkim/opendkim.pid
User=opendkim
ExecStart=/usr/sbin/opendkim -P /var/run/opendkim/opendkim.pid -p $SOCKET
Restart=on-failure
ExecReload=/bin/kill -USR1 $MAINPID

[Install]
WantedBy=multi-user.target
EOT

The specific changes here are lines #9 EnvironmentFile #13 -p $SOCKET

Defaults File

cat > /etc/default/opendkim <<EOT
SOCKET="inet:12301@localhost"
EOT

Opendkim Config file

cat > /etc/opendkim <<EOT
Mode                sv
Syslog              yes
SyslogSuccess       yes
LogWhy              yes
#Socket              inet:12301@localhost
Umask               002
SendReports         yes
SoftwareHeader      yes
Canonicalization    relaxed/relaxed
Selector            default
MinimumKeyBits      1024
KeyTable            refile:/etc/dkimkeys/KeyTable
SigningTable        refile:/etc/dkimkeys/SigningTable
ExternalIgnoreList  refile:/etc/dkimkeys/TrustedHosts
OversignHeaders     From
TrustAnchorFile     /usr/share/dns/root.key
EOT

Specific changes here are lines #7 hashed out socket file,  it simply does not work.
The only way to get opendkim to honour this setting is passing it to the command line #13 of the service file.

Modify /etc/postfix/main.cf and add/edit the following lines

smtpd_milters = inet:localhost:12301
non_smtpd_milters = inet:localhost:12301

Create referenced folders for your open dkim keys

mkdir -vp /etc/dkimkeys/keys

TrustedHosts

cat > /etc/dkimkeys/TrustHosts <<EOT
127.0.0.1
::1
localhost
example.com
*.exmaple.com
EOT

SingingTable

cat > /etc/dkimkeys/SigningTable <<EOT
*@exmaple.com default._domainkey.example.com
EOT

KeyTable

cat> /etc/dkimkeys/KeyTable <<EOT
default._domainkey.example.com example.com:default:/etc/dkimkeys/keys/default.private
EOT

Create private/public key for signing

cd /etc/dkimkeys/keys
opendkim-genkey -s default

Your directory should now look like this

Opendkim Treeview of files

Tell systemd to reload the the daemon files and restart

systemctl daemon-reload
systemctl restart opendkim
systemctl restart postfix

DNS

Now go modify your DNS, adding a TXT record ‘default._domainkey‘.
Copy and paste everything between the parenthesis. ( everything here ) into the value field of the TXT record

cat keys/default.txt 
default._dkim   IN      TXT     ( "v=DKIM1; k=rsa; "
          "p=MIGfMA0GCSqGSIGNA....BIG LONG DIRTY HASH ....ciaxOhS24T4MFwIDAQAB" )  ; ----- DKIM key default for com

Enjoy

Other resources
https://www.google.com/search?q=opendkim+setup