hackerbruecke.net

postgrey

anonymous@undisclosed.example.com (Anonymous) — Tue, 25 Apr 2017 16:02:27 +0000

Greylisting For a overview what greylisting does, have a look at www.greylisting.org/ There are several greylisting daemons for Postfix available. I stick to David Schweikert's Postgrey or to Lionel Bouton's SQLgrey in combination with it's web-interface http://www.vanheusden.com/sgwi/ Postgrey Postgrey greylisting daemon

relayhost

anonymous@undisclosed.example.com (Anonymous) — Tue, 25 Apr 2017 14:56:33 +0000

Postfix configuration for a relayhost (MX) / Anti-SPAM-/UCE-settings smtpd (smtp + daemon) = server = Postfix receives mail from a client smtp = client = Postfix sends mail to another mailserver used Ports: 10023/tcp: postgrey 10024/tcp: amavisd-new 10025/tcp: policyd-weight

spamassassin

anonymous@undisclosed.example.com (Anonymous) — Tue, 25 Apr 2017 14:58:39 +0000

SpamAssassin SA-config-genarator: /etc/mail/spamassassin/local.cf: # SpamAssassin config file for version 3.x # NOTE: NOT COMPATIBLE WITH VERSIONS 2.5 or 2.6 # See http://www.yrex.com/spam/spamconfig25.php for earlier versions # Generated by http://www.yrex.com/spam/spamconfig.php (version 1.50) # How many hits before a message is considered spam. required_score 5.0 # Encapsulate spam in an attachment (0=no, 1=yes, 2=safe) report_safe …

monitoring

anonymous@undisclosed.example.com (Anonymous) — Tue, 25 Apr 2017 14:58:04 +0000

Monitoring email-monitoring * create „/var/lib/rrd“ Mailgraph mailgraph is a very simple mail statistics RRDtool frontend for Postfix that produces daily, weekly, monthly and yearly graphs of received/sent and bounced/rejected mail (SMTP traffic).

sign

anonymous@undisclosed.example.com (Anonymous) — Tue, 25 Apr 2017 14:53:39 +0000

Domain Key Identified Mail outbound - ORIGINATING - signieren DKIM basiert auf asymetrischer Verschlüsselung mit public- und private-Key. Das Key-Paar wird mit folgender Syntax erzeugt: amavisd genrsa [Anzahl der Bits für den Schlüssel]

amavisd

anonymous@undisclosed.example.com (Anonymous) — Tue, 25 Apr 2017 14:57:55 +0000

AmaVisd-new /etc/amavis/amavisd.conf: use strict; # a minimalistic configuration file for amavisd-new with all necessary settings # # see amavisd.conf-default for a list of all variables with their defaults; # see amavisd.conf-sample for a traditional-style commented file; # for more details see documentation in INSTALL, README_FILES/* # and at http://www.ijs.si/software/amavisd/amavisd-new-docs.html # COMMONLY ADJUSTED SETTINGS: # @bypass_virus_checks_maps = (1); # uncomment to DI…

postfix_secure

anonymous@undisclosed.example.com (Anonymous) — Tue, 25 Apr 2017 14:56:23 +0000

Postfix with TLS and SSL (smtps) Use a portscanner like „nmap“: station7:/etc/init.d # nmap localhost | grep smtp 25/tcp open smtp -> smtp is only running at port 25! TLS Modify the TLS-settings in /etc/postfix/main.cf #--- SSL/TLS setting ---# smtpd_client_restrictions= permit_tls_clientcerts, permit_sasl_authenticated smtpd_recipient_restrictions = permit_mynetworks, permit_sasl_authenticated, permit_tls_clientcerts, reject_unauth_destination, check_sender_access hash:/etc/…

sasl

anonymous@undisclosed.example.com (Anonymous) — Tue, 25 Apr 2017 14:56:42 +0000

SASL A very conveniant way of configuring the Simple Authentication and Security Layer (SASL) is to use the Pluggable Authentication Modules (PAM), since it can use diffrent authentication sources like ldap or /etc/passwd - thus SASL is everything but simple

config

anonymous@undisclosed.example.com (Anonymous) — Sat, 06 Apr 2024 16:56:19 +0000

Postfix smtpd (smtp + daemon) = server = Postfix receives mail from a client smtp = client = Postfix sends mail to another mailserver Edit /etc/postfix/main.cf queue_directory = /var/spool/postfix command_directory = /usr/sbin daemon_directory = /usr/libexec/postfix mail_owner = postfix smtpd_banner = mail.example.org myhostname = mail.example.org myorigin = example.org mydestination = mail.example.org mynetworks = 127.0.0.0/8, 10.0.0.0/8 alias_maps = hash:/etc/aliases, ldap:virtualaliases…

smtp-authentication

anonymous@undisclosed.example.com (Anonymous) — Tue, 25 Apr 2017 14:56:50 +0000

SMTPd- / SMTP-authentication SMTPd-authentication SASL must be configured! in /etc/postfix/main.cf: smtpd_sasl_auth_enable = yes smtpd_sasl_security_options = noanonymous broken_sasl_auth_clients = yes smtpd_recipient_restrictions = ... permit_sasl_authenticated