Add backwards compatibility for old dns_blocklists.cf files

[DocFraggle]

Contribution Guidelines

• [ X ] I've read the contribution guidelines and wholeheartedly agree them

What does this PR include?

Short Description

Some people had problems with the latest mailcow release (2024-11, see https://community.mailcow.email/d/4244-i-no-longer-receive-emails-and-i-no-longer-send-emails). The reason for the problems was an older version of data/conf/postfix/dns_blocklists.cf which was created with another indentation than the currently used one.
A new Postfix config line was introduced in c53bf85 which led to erroneous parsing due to the indentation and resulting in this error:

bad numerical configuration: lmtp_destination_recipient_limit = 1 postscreen_dnsbl_sites = wl.mailspike.net=127.0.0.[18;19;20]-2 hostkarma.junkemailfilter.com=127.0.0.1-2 list.dnswl.org=127.0.[0..255].0-2 list.dnswl.org=127.0.[0..255].1-4 list.dnswl.org=127.0.[0..255].2-6 list.dnswl.org=127.0.[0..255].3-8 ix.dnsbl.manitu.net2 bl.spamcop.net2 bl.suomispam.net2 hostkarma.junkemailfilter.com=127.0.0.23 hostkarma.junkemailfilter.com=127.0.0.42 hostkarma.junkemailfilter.com=127.0.1.21 backscatter.spameatingmonkey.net2 bl.ipv6.spameatingmonkey.net2 bl.spameatingmonkey.net2 b.barracudacentral.org=127.0.0.27 bl.mailspike.net=127.0.0.25 bl.mailspike.net=127.0.0.[10;11;12]4 dnsbl.sorbs.net=127.0.0.108 dnsbl.sorbs.net=127.0.0.56 dnsbl.sorbs.net=127.0.0.73 dnsbl.sorbs.net=127.0.0.82 dnsbl.sorbs.net=127.0.0.62 dnsbl.sorbs.net=127.0.0.92 zen.spamhaus.org=127.0.0.[10;11]8 zen.spamhaus.org=127.0.0.[4..7]6 zen.spamhaus.org=127.0.0.34 zen.spamhaus.org=127.0.0.23 zen.spamhaus.org=127.0.0.[10;11]8 zen.spamhaus.org=127.0.0.[4..7]6 zen.spamhaus.org=127.0.0.34 zen.spamhaus.org=127.0.0.23

Due to the indentation of data/conf/postfix/dns_blocklists.cf the content was added to the lmtp_destination_recipient_limit parameter, leading to the error.

The fix strips the whitespaces at the beginning of the line containing "postscreen_dnsbl_sites" to restore a proper indentation.

Affected Containers

• postfix

Did you run tests?

Yes

What did you tested?

Edited /opt/postfix.sh inside the container to apply my new command, tested multiple variants of the dns_blocklists.cf file

What were the final results? (Awaited, got)

The indentation was corrected.

Before:

root@b01960898244:/# postconf -c /opt/postfix/conf/ | grep lmtp_destination_recipient_limit
lmtp_destination_recipient_limit = 1 postscreen_dnsbl_sites = wl.mailspike.net=127.0.0.[18;19;20]*-2 hostkarma.junkemailfilter.com=127.0.0.1*-2 list.dnswl.org=127.0.[0..255].0*-2 list.dnswl.org=127.0.[0..255].1*-4 list.dnswl.org=127.0.[0..255].2*-6 list.dnswl.org=127.0.[0..255].3*-8 ix.dnsbl.manitu.net*2 bl.spamcop.net*2 bl.suomispam.net*2 hostkarma.junkemailfilter.com=127.0.0.2*3 hostkarma.junkemailfilter.com=127.0.0.4*2 hostkarma.junkemailfilter.com=127.0.1.2*1 backscatter.spameatingmonkey.net*2 bl.ipv6.spameatingmonkey.net*2 bl.spameatingmonkey.net*2 b.barracudacentral.org=127.0.0.2*7 bl.mailspike.net=127.0.0.2*5 bl.mailspike.net=127.0.0.[10;11;12]*4 dnsbl.sorbs.net=127.0.0.10*8 dnsbl.sorbs.net=127.0.0.5*6 dnsbl.sorbs.net=127.0.0.7*3 dnsbl.sorbs.net=127.0.0.8*2 dnsbl.sorbs.net=127.0.0.6*2 dnsbl.sorbs.net=127.0.0.9*2 zen.spamhaus.org=127.0.0.[10;11]*8 zen.spamhaus.org=127.0.0.[4..7]*6 zen.spamhaus.org=127.0.0.3*4 zen.spamhaus.org=127.0.0.2*3 zen.spamhaus.org=127.0.0.[10;11]*8 zen.spamhaus.org=127.0.0.[4..7]*6 zen.spamhaus.org=127.0.0.3*4 zen.spamhaus.org=127.0.0.2*3

root@b01960898244:/# postconf -c /opt/postfix/conf/ | grep postscreen_dnsbl_sites 
postscreen_dnsbl_sites =

After:

root@b01960898244:/# postconf -c /opt/postfix/conf/ | grep lmtp_destination_recipient_limit
lmtp_destination_recipient_limit = 1 

root@b01960898244:/# postconf -c /opt/postfix/conf/ | grep postscreen_dnsbl_sites 
postscreen_dnsbl_sites = wl.mailspike.net=127.0.0.[18;19;20]*-2 hostkarma.junkemailfilter.com=127.0.0.1*-2 list.dnswl.org=127.0.[0..255].0*-2 list.dnswl.org=127.0.[0..255].1*-4 list.dnswl.org=127.0.[0..255].2*-6 list.dnswl.org=127.0.[0..255].3*-8 ix.dnsbl.manitu.net*2 bl.spamcop.net*2 bl.suomispam.net*2 hostkarma.junkemailfilter.com=127.0.0.2*3 hostkarma.junkemailfilter.com=127.0.0.4*2 hostkarma.junkemailfilter.com=127.0.1.2*1 backscatter.spameatingmonkey.net*2 bl.ipv6.spameatingmonkey.net*2 bl.spameatingmonkey.net*2 b.barracudacentral.org=127.0.0.2*7 bl.mailspike.net=127.0.0.2*5 bl.mailspike.net=127.0.0.[10;11;12]*4 dnsbl.sorbs.net=127.0.0.10*8 dnsbl.sorbs.net=127.0.0.5*6 dnsbl.sorbs.net=127.0.0.7*3 dnsbl.sorbs.net=127.0.0.8*2 dnsbl.sorbs.net=127.0.0.6*2 dnsbl.sorbs.net=127.0.0.9*2 zen.spamhaus.org=127.0.0.[10;11]*8 zen.spamhaus.org=127.0.0.[4..7]*6 zen.spamhaus.org=127.0.0.3*4 zen.spamhaus.org=127.0.0.2*3 zen.spamhaus.org=127.0.0.[10;11]*8 zen.spamhaus.org=127.0.0.[4..7]*6 zen.spamhaus.org=127.0.0.3*4 zen.spamhaus.org=127.0.0.2*3

[DerLinkman]

Sorry, but that idea came a bit late...

But thank you for your idea/PR anyways :)

[DocFraggle]

So you already fixed this? Because I don't see any changes fixing the problem in the stable/master branch

EDIT: ok, found it