<?xml version="1.0" encoding="UTF-8"?>
<!-- generator="FeedCreator 1.8" -->
<?xml-stylesheet href="https://www.hackerbruecke.net/lib/exe/css.php?s=feed" type="text/css"?>
<rss version="2.0">
    <channel xmlns:g="http://base.google.com/ns/1.0">
        <title>hackerbruecke.net</title>
        <description>Christophs outsourced brain</description>
        <link>https://www.hackerbruecke.net/</link>
        <lastBuildDate>Sun, 12 Apr 2026 15:02:31 +0000</lastBuildDate>
        <generator>FeedCreator 1.8</generator>
        <image>
            <url>https://www.hackerbruecke.net/_media/wiki/favicon.ico</url>
            <title>hackerbruecke.net</title>
            <link>https://www.hackerbruecke.net/</link>
        </image>
        <item>
            <title>relayhost</title>
            <link>https://www.hackerbruecke.net/linux/email/postfix/relayhost?rev=1493132193&amp;do=diff</link>
            <description>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</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 25 Apr 2017 14:56:33 +0000</pubDate>
        </item>
        <item>
            <title>monitoring</title>
            <link>https://www.hackerbruecke.net/linux/email/monitoring/monitoring?rev=1493132284&amp;do=diff</link>
            <description>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).</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 25 Apr 2017 14:58:04 +0000</pubDate>
        </item>
        <item>
            <title>email</title>
            <link>https://www.hackerbruecke.net/linux/email/email?rev=1493137617&amp;do=diff</link>
            <description>email

Mailserver, Mailgateway, Anti-Spam [AMaVISd-new, SpamAssassin, dSpam, rspamd], SPF, DKIM, PFS etc.
\\}}


Postfix smtpd

Postfix ist ein sehr mächtiger Mail Transport Agent, entwickelt von Wietse Venema.


	*  Postfix Konfiguration für einen Mailserver
	*  use of LDAP lookup maps
	*  Postfix&#039; Postscreen Modul anstatt policyd-weight oder postfwd
	*  Postfix Anti-SPAM/UCE settings
	*  Postfix SASL Konfiguraton
	*  SMTP-authentication
	*  TLS and SSL configuration (smtps)
	*</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 25 Apr 2017 16:26:57 +0000</pubDate>
        </item>
        <item>
            <title>postgrey</title>
            <link>https://www.hackerbruecke.net/linux/email/greylisting/postgrey?rev=1493136147&amp;do=diff</link>
            <description>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&#039;s Postgrey or to Lionel Bouton&#039;s SQLgrey in combination with it&#039;s web-interface http://www.vanheusden.com/sgwi/



Postgrey

Postgrey greylisting daemon</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 25 Apr 2017 16:02:27 +0000</pubDate>
        </item>
        <item>
            <title>config</title>
            <link>https://www.hackerbruecke.net/linux/email/postfix/config?rev=1712422579&amp;do=diff</link>
            <description>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…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 06 Apr 2024 16:56:19 +0000</pubDate>
        </item>
        <item>
            <title>pfs</title>
            <link>https://www.hackerbruecke.net/linux/email/postfix/pfs?rev=1493132175&amp;do=diff</link>
            <description>Postfix Perfect Forwarding Secrecy (PFS)


openssl gendh -out /etc/postfix/dh_512.pem -2 512
openssl gendh -out /etc/postfix/dh_1024.pem -2 1024

postconf -e &quot;smtpd_tls_dh1024_param_file = /etc/postfix/dh_1024.pem&quot;
postconf -e &quot;smtpd_tls_dh512_param_file = /etc/postfix/dh_512.pem&quot;
postconf -e &quot;smtpd_tls_eecdh_grade = strong&quot;
postconf -e &quot;tls_preempt_cipherlist = yes&quot;
postconf -e &quot;smtpd_tls_loglevel = 1&quot;
postconf -e &quot;smtp_tls_loglevel = 1&quot;

postfix reload</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 25 Apr 2017 14:56:15 +0000</pubDate>
        </item>
        <item>
            <title>postfix_secure</title>
            <link>https://www.hackerbruecke.net/linux/email/postfix/postfix_secure?rev=1493132183&amp;do=diff</link>
            <description>Postfix with TLS and SSL (smtps)

Use a portscanner like „nmap“:
station7:/etc/init.d # nmap localhost | grep smtp
25/tcp   open  smtp


-&gt; 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/…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 25 Apr 2017 14:56:23 +0000</pubDate>
        </item>
        <item>
            <title>sign</title>
            <link>https://www.hackerbruecke.net/linux/email/amavisd/dkim/sign?rev=1493132019&amp;do=diff</link>
            <description>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 &lt;Dateiname&gt; [Anzahl der Bits für den Schlüssel]</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 25 Apr 2017 14:53:39 +0000</pubDate>
        </item>
        <item>
            <title>commserv</title>
            <link>https://www.hackerbruecke.net/linux/commserv?rev=1493132445&amp;do=diff</link>
            <description>This documentation is work in progress, no liability for correctness can be given!  




Communications-Server

Motivation

Because I had to look for a log time around the Internet, asking a lot of questions on mailing-lists, reading books and talking to friends for configuring my commserv, thus having quite a bit of hassle getting things working, I&#039;d like give my experiences back to the comunity.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 25 Apr 2017 15:00:45 +0000</pubDate>
        </item>
        <item>
            <title>smtp-authentication</title>
            <link>https://www.hackerbruecke.net/linux/email/postfix/smtp-authentication?rev=1493132210&amp;do=diff</link>
            <description>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</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 25 Apr 2017 14:56:50 +0000</pubDate>
        </item>
        <item>
            <title>amavisd</title>
            <link>https://www.hackerbruecke.net/linux/email/amavisd/amavisd?rev=1493132275&amp;do=diff</link>
            <description>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…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 25 Apr 2017 14:57:55 +0000</pubDate>
        </item>
        <item>
            <title>pflogsum</title>
            <link>https://www.hackerbruecke.net/linux/email/monitoring/pflogsum?rev=1493132162&amp;do=diff</link>
            <description>Postfix-Reporting mit Pflogsum


apt-get install pflogsum


/usr/local/bin/postfix_report.sh


#!/bin/bash 

/usr/sbin/pflogsumm -d yesterday --problems_first /var/log/mail.log.1 &gt; /tmp/pflogsumm
/usr/bin/mailx -s &quot;Automatischer Postfix-Report von $(hostname)&quot; -r postfix-admin@station7.example.de postfix-admin@station7.example.de &lt; /tmp/pflogsumm</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 25 Apr 2017 14:56:02 +0000</pubDate>
        </item>
        <item>
            <title>ca</title>
            <link>https://www.hackerbruecke.net/linux/commserv/ca/ca?rev=1293466844&amp;do=diff</link>
            <description>Certificate Authority

generate certificate and key-files using e.g. one of the follwing

	*  simple OpenSSL CA
	*  Tiny CA
	*  phpki CA




trusting your Certificate Authority

Ensure there&#039;s only one CA certificate in the file from your CA. Normally there is, but ocassionally several are stored in the same file. To list the number of certificates in a file, use the command below. If you get an answer of more than one, then see the section on multiple certificates in one file. The command to ch…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 27 Dec 2010 16:20:44 +0000</pubDate>
        </item>
        <item>
            <title>config</title>
            <link>https://www.hackerbruecke.net/linux/email/cyrus/config?rev=1493131953&amp;do=diff</link>
            <description>Cyrus imapd / popd



&lt;http://www.opensuse.org&gt;Modify /etc/cyrus.conf to:


START {
  recover       cmd=&quot;ctl_cyrusdb -r&quot;
  deliver       cmd=&quot;ctl_deliver -r&quot;
}

SERVICES {
  imap          cmd=&quot;imapd&quot; listen=&quot;imap&quot; prefork=0
  #  imaps                cmd=&quot;imapd -s&quot; listen=&quot;imaps&quot; prefork=0
  pop3          cmd=&quot;pop3d&quot; listen=&quot;pop3&quot; prefork=0
  #  pop3s                cmd=&quot;pop3d -s&quot; listen=&quot;pop3s&quot; prefork=0
  sieve         cmd=&quot;timsieved&quot; listen=&quot;sieve&quot; prefork=2
  # entry must be the same as in th…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 25 Apr 2017 14:52:33 +0000</pubDate>
        </item>
        <item>
            <title>ldap</title>
            <link>https://www.hackerbruecke.net/linux/email/postfix/ldap?rev=1493132150&amp;do=diff</link>
            <description>using LDAP

/etc/postfix/ldap-aliases.cf:
server_host= ldaps://localhost:636
server_port= 636
start_tls = no
tls_ca_cert_file = /etc/ssl/postfix/certs/ca_cert.pem
tls_ca_cert_dir = /etc/ssl/postfix/certs/
tls_cert = /etc/ssl/postfix/certs/station7_cert.pem
tls_key = /etc/ssl/postfix/private/station7_key.pem
#tls_random_file = dev:/dev/urandom
tls_cipher_suite = ALL:!ADH:RC4+RSA:+HIGH:+MEDIUM:+LOW:+SSLv3:+EXP
version= 3
bind= no
timeout= 120
search_base= dc=example,dc=com
query_filter = (&amp;(object…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 25 Apr 2017 14:55:50 +0000</pubDate>
        </item>
        <item>
            <title>config_test</title>
            <link>https://www.hackerbruecke.net/linux/email/postfix/config_test?rev=1493132127&amp;do=diff</link>
            <description>Postfix-Konfiguration testen

Die Postfix-Konfigurtation sollte auf alle fälle vor der Produktivnahme ausgiebig getestet und das Verhalten beobachtet werden!




Test von main.cf und master.cf

Test der Datei- und Verzeichnisrechte, sowie die Syntax von main.cf und master.cf von Postfix:</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 25 Apr 2017 14:55:27 +0000</pubDate>
        </item>
        <item>
            <title>sasl</title>
            <link>https://www.hackerbruecke.net/linux/email/postfix/sasl?rev=1493132202&amp;do=diff</link>
            <description>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</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 25 Apr 2017 14:56:42 +0000</pubDate>
        </item>
        <item>
            <title>todo</title>
            <link>https://www.hackerbruecke.net/linux/commserv/todo?rev=1293466842&amp;do=diff</link>
            <description>ToDo

Things, that have to be documented:

	*  generating the decrypted SSL-key with OpenSSL-CA
	*  use of TinyCA and phpki-CA
	*  Postfix: main.cf and master.cf
	*  implement &lt;http://www.contentschmiede.de/archiv/2005/08/26/postfix_fuer_typo3_und_gmx_fit_machen/&gt; in email -&gt; Postfix -&gt; SMTPd- / SMTP-Authentication</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 27 Dec 2010 16:20:42 +0000</pubDate>
        </item>
        <item>
            <title>all</title>
            <link>https://www.hackerbruecke.net/linux/debian/all?rev=1493131598&amp;do=diff</link>
            <description>2014-08-08



zuerst „Debian OS-Basis-Installation auf Blech“ durchfuehren!!!

auf allen Server-Instanzen („Blech“, Linux VServer, LXC):



### Proxy der UKBW fuer die Installations-Shellsitzung setzen:
export http_proxy=„&lt;http://proxy01.ukbw.de:3128/&gt;“

### LiHAS GPG-Key importieren:
wget -O -</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 25 Apr 2017 14:46:38 +0000</pubDate>
        </item>
        <item>
            <title>dkim</title>
            <link>https://www.hackerbruecke.net/linux/email/amavisd/dkim?rev=1493135342&amp;do=diff</link>
            <description>Postfix mit Domain Key Identifified Mail (DKIM)

Vorausssetzung für DKIM ist ein installiertes -&gt; AMaVIS.

Auch bei DKIM wird, wie bei allen anderen Signaturen, in zwei Richtngen unterschieden:


	*  eingehende emails (inbound): Überprüfung von DKIM-Signaturen in emails</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 25 Apr 2017 15:49:02 +0000</pubDate>
        </item>
        <item>
            <title>cyrus_secure</title>
            <link>https://www.hackerbruecke.net/linux/email/cyrus/cyrus_secure?rev=1493131964&amp;do=diff</link>
            <description>TLS, IMAP over SSL (imaps) and pop3 over SSL (pop3s)

TLS

Modify / append the TLS-settings in /etc/imap.conf:
#--- SSL/TLS setting ---#
tls_ca_path: /etc/ssl/certs
tls_ca_file: /etc/ssl/certs/ca_cert.pem
tls_cert_file: /etc/ssl/certs/station7_cert.pem
tls_key_file: /etc/ssl/private/station7_key.pem</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 25 Apr 2017 14:52:44 +0000</pubDate>
        </item>
        <item>
            <title>gnarwl</title>
            <link>https://www.hackerbruecke.net/linux/email/gnarwl?rev=1493131823&amp;do=diff</link>
            <description>Gnarwl

Download GNARWL software from &lt;http://www.home.unix-ag.org/patrick/index.php?gnarwl&gt; and download package named gnarwl-3.3.tgz 




Compile GNARWL for LDAP vacations
# tar xzvf gnarwl-3.3.tgz
# cd gnarwl-3.3
# ./configure
# make
# make install
# make perm
Adjust File /usr/local/etc/gnarwl.conf
map_sender $sender
map_receiver $recepient
map_subject $subject
map_field $fullname cn
map_field $deputy mail
server localhost
port 389
scope sub
login cn=admin,dc=example,dc=org
password IveGotASe…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 25 Apr 2017 14:50:23 +0000</pubDate>
        </item>
        <item>
            <title>spf</title>
            <link>https://www.hackerbruecke.net/linux/email/amavisd/spf?rev=1493132219&amp;do=diff</link>
            <description>Postfix und das Sender Policy Framework (SPF)

Das Sender Policy Framework - früher auch Sender Permitted From genannt -, soll das Fälschen des email-Absenders in einer E-Mail auf SMTP-Ebene erschweren.



Mithilfe eines SPF-Generators, z.B. &lt;http://spfwizard.com/&gt; oder</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 25 Apr 2017 14:56:59 +0000</pubDate>
        </item>
        <item>
            <title>spamreport</title>
            <link>https://www.hackerbruecke.net/linux/email/spamassassin/spamreport?rev=1493132098&amp;do=diff</link>
            <description>Spamreport




spamcheck.sh


#!/bin/bash

#########################################################
# UKBW-Spam-Report, 2007-05-01, chhaas, IuK / Netzwerke #
#########################################################

#set -o verbose

########
# ToDo #
########
# - printvariablen bei &quot;grep X-Spam-Status:&quot; korrigieren
# - Mail an antispam@uk-bw.de zusammenfassen: 1 Mail die alle Spammails inkl. Empfaenger beinhaltet
# - Variablen fuer FROM: und RETURN-PATH einrichten
# - evtl. SpamAssassin Spam-T…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 25 Apr 2017 14:54:58 +0000</pubDate>
        </item>
        <item>
            <title>email-server</title>
            <link>https://www.hackerbruecke.net/linux/email-server?rev=1505485138&amp;do=diff</link>
            <description>email



	*  MTA/SMTPd Postfix (Mailserver, Mailgateway, Anti-Spam [AMaVISd-new, SpamAssassin, dSpam], SPF, DKIM, PFS etc.)
	*  MDA/IMAPd Cyrus
	*  MDA/IMAPd Dovecot</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 15 Sep 2017 14:18:58 +0000</pubDate>
        </item>
        <item>
            <title>linux</title>
            <link>https://www.hackerbruecke.net/linux/linux?rev=1715428233&amp;do=diff</link>
            <description>Debian-Installation

	*  Installation von GNU/Debian auf Hardware oder virtueller Instanz
	*  zweite Netzwerkkarte mit wechselnder Konfiguration






securing DNS and Mail

	*  Domain Name System Security Extensions (DNSSEC) mit Bind9
	*  DNS-based Authentication of Named Entities (DANE) und TLS Authentication record (TLSA)
	*  Sender Policy Framework (SPF)
	*  DomainKeys Identified Mail (DKIM)
	*  Domain-based Message Authentication, Reporting and Conformance (DMARC)
	*  Authenticated Received…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 11 May 2024 11:50:33 +0000</pubDate>
        </item>
        <item>
            <title>installation</title>
            <link>https://www.hackerbruecke.net/linux/commserv/installation?rev=1408110705&amp;do=diff</link>
            <description>Installation of the Linux OS



SuSE 10.0 Professional

Because of problems with the 64-bit-version of the CAPI-driver for the AVM B1-Cards used in my commserv, only the 32-bit-version of SUSE 10.0 can be used. Maybe with later versions of openSUSE this changes</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 15 Aug 2014 13:51:45 +0000</pubDate>
        </item>
        <item>
            <title>config</title>
            <link>https://www.hackerbruecke.net/linux/commserv/gosa/config?rev=1293466843&amp;do=diff</link>
            <description>GOsa

GOsa is a GPL&#039;ed PHP based administration tool for managing accounts and systems in LDAP databases. It administers users and groups, mail distribution lists, thin clients, applications, phones and faxes. 

Get GOsa from: &lt;http://oss.gonicus.de/pub/gosa/&gt; 

Project homepage: &lt;http://www.gosa-project.org/&gt;</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 27 Dec 2010 16:20:43 +0000</pubDate>
        </item>
        <item>
            <title>tipps</title>
            <link>https://www.hackerbruecke.net/linux/email/postfix/tipps?rev=1493132245&amp;do=diff</link>
            <description>Postfix Tipps und Tricks




Mails aus Mailqueue löschen

alle Mails des Benutzers station7@example.com aus der Mailqueue löschen:


mail:~# mailq | tail -n +2 | grep -v &#039;^ *(&#039; | awk  &#039;BEGIN { RS = &quot;&quot; } { if ($7 == &quot;station7@example.com&quot;) print $1 }&#039; | tr -d &#039;*!&#039; | postsuper -d -</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 25 Apr 2017 14:57:25 +0000</pubDate>
        </item>
    </channel>
</rss>
