nachfolgend findet Ihr eine Basis-Konfiguration für Postfix >= 3.0.0 inklusive SASL (per Dovecot-IMAP) und TLS/SSL (SMTP-AUTH), welche die Empfehlungen aus dem Postfix Anti-UCE Cheat Sheet umsetzt und für Maildir-Systemuser vorkonfiguriert ist.
Postfix konfigurieren:
Code: Select all
mv /etc/postfix/main.cf /etc/postfix/main.cf.back
mv /etc/postfix/master.cf /etc/postfix/master.cf.back
cat > /etc/postfix/main.cf << "EOF"
allow_percent_hack = no
always_add_missing_headers = yes
biff = no
compatibility_level = 2
data_directory = /var/lib/postfix
disable_vrfy_command = yes
dovecot_destination_recipient_limit = 1
enable_long_queue_ids = yes
fast_flush_domains =
home_mailbox = .maildir/
inet_interfaces = all
inet_protocols = all
lmtp_tls_fingerprint_digest = sha1
local_header_rewrite_clients = permit_mynetworks permit_sasl_authenticated
mail_spool_directory = /var/vmail
mailbox_size_limit = 0
masquerade_domains = $mydomain
masquerade_exceptions = root mailer-daemon
message_size_limit = 0
mydestination = $myhostname localhost.$mydomain localhost
mydomain = example.com
myhostname = mail.$mydomain
mynetworks_style = host
notify_classes = data protocol resource software
openssl_path = /usr/bin/openssl
postscreen_bare_newline_action = enforce
postscreen_bare_newline_enable = yes
postscreen_dnsbl_action = enforce
postscreen_dnsbl_sites =
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
zen.spamhaus.org=127.0.0.9*25
zen.spamhaus.org=127.0.0.3*10
zen.spamhaus.org=127.0.0.2*5
zen.spamhaus.org=127.0.0.[4..7]*3
zen.spamhaus.org=127.0.0.[10..11]*3
swl.spamhaus.org*-10
bl.mailspike.net=127.0.0.2*10
bl.mailspike.net=127.0.0.10*5
bl.mailspike.net=127.0.0.11*4
bl.mailspike.net=127.0.0.12*3
bl.mailspike.net=127.0.0.13*2
bl.mailspike.net=127.0.0.14*1
wl.mailspike.net=127.0.0.16*-2
wl.mailspike.net=127.0.0.17*-4
wl.mailspike.net=127.0.0.18*-6
wl.mailspike.net=127.0.0.19*-8
wl.mailspike.net=127.0.0.20*-10
backscatter.spameatingmonkey.net*2
bl.ipv6.spameatingmonkey.net*2
bl.spameatingmonkey.net*2
ix.dnsbl.manitu.net*2
bl.spamcop.net*2
db.wpbl.info*2
psbl.surriel.com*2
torexit.dan.me.uk*2
tor.dan.me.uk*1
safe.dnsbl.sorbs.net*1
postscreen_dnsbl_threshold = 5
postscreen_dnsbl_whitelist_threshold = 0
postscreen_greet_action = enforce
postscreen_non_smtp_command_enable = yes
postscreen_pipelining_enable = yes
queue_directory = /var/spool/postfix
recipient_delimiter = +
remote_header_rewrite_domain = domain.invalid
show_user_unknown_table_name = no
smtp_dns_support_level = enabled
### Bitte den richtigen Pfad aktivieren:
# centos/fedora: openssl
#smtp_tls_CAfile = /etc/pki/tls/certs/ca-bundle.crt
# debian/ubuntu/arch/gentoo: ca-certificates
#smtp_tls_CAfile = /etc/ssl/certs/ca-certificates.crt
# freebsd: ca_root_nss
#smtp_tls_CAfile = /usr/local/share/certs/ca-root-nss.crt
smtp_tls_ciphers = medium
smtp_tls_exclude_ciphers = CAMELLIA SEED IDEA RC2 RC4 aDSS kECDHe kECDHr kDHd kDHr eNULL aNULL MEDIUM LOW EXPORT
smtp_tls_fingerprint_digest = sha1
smtp_tls_loglevel = 1
smtp_tls_mandatory_ciphers = medium
smtp_tls_mandatory_exclude_ciphers = CAMELLIA SEED IDEA RC2 RC4 aDSS kECDHe kECDHr kDHd kDHr eNULL aNULL MEDIUM LOW EXPORT
smtp_tls_note_starttls_offer = yes
smtp_tls_security_level = may
smtp_tls_session_cache_database = btree:${data_directory}/smtp_scache
smtpd_client_port_logging = yes
smtpd_client_restrictions =
sleep 1
permit
smtpd_data_restrictions =
reject_unauth_pipelining
reject_multi_recipient_bounce
permit
smtpd_end_of_data_restrictions =
permit
smtpd_etrn_restrictions =
reject
smtpd_helo_required = yes
smtpd_helo_restrictions =
permit_mynetworks
permit_sasl_authenticated
reject_invalid_helo_hostname
reject_non_fqdn_helo_hostname
permit
#smtpd_milters = inet:127.0.0.1:8891 inet:127.0.0.1:8893
smtpd_recipient_restrictions =
permit_mynetworks
permit_sasl_authenticated
reject_non_fqdn_recipient
reject_unknown_recipient_domain
check_recipient_access pcre:${config_directory}/recipient_checks.pcre
permit
smtpd_relay_restrictions =
permit_mynetworks
permit_sasl_authenticated
defer_unauth_destination
permit
smtpd_sasl_auth_enable = yes
smtpd_sasl_authenticated_header = yes
smtpd_sasl_path = private/auth
smtpd_sasl_type = dovecot
smtpd_sender_restrictions =
reject_non_fqdn_sender
reject_unknown_sender_domain
permit
smtpd_tls_auth_only = yes
smtpd_tls_cert_file = /etc/ssl/certs/mail.example.com.crt
smtpd_tls_ciphers = medium
smtpd_tls_exclude_ciphers = CAMELLIA SEED IDEA RC2 RC4 aDSS kECDHe kECDHr kDHd kDHr eNULL aNULL MEDIUM LOW EXPORT
smtpd_tls_fingerprint_digest = sha1
smtpd_tls_key_file = /etc/ssl/private/mail.example.com.key
smtpd_tls_loglevel = 1
smtpd_tls_mandatory_ciphers = medium
smtpd_tls_mandatory_exclude_ciphers = CAMELLIA SEED IDEA RC2 RC4 aDSS kECDHe kECDHr kDHd kDHr eNULL aNULL MEDIUM LOW EXPORT
smtpd_tls_received_header = yes
smtpd_tls_security_level = may
smtpd_tls_session_cache_database = btree:${data_directory}/smtpd_scache
strict_rfc821_envelopes = yes
swap_bangpath = no
tls_daemon_random_bytes = 64
tls_high_cipherlist = EECDH+ECDSA+CHACHA20 EECDH+CHACHA20 EECDH+ECDSA+AESGCM EECDH+AESGCM EECDH+ECDSA+AES256 EECDH+AES256 EECDH+ECDSA+AES128 EECDH+AES128 EECDH+ECDSA+3DES EECDH+3DES EDH+CHACHA20 EDH+AESGCM EDH+AES256 EDH+AES128 EDH+3DES
tls_medium_cipherlist = EECDH+ECDSA+CHACHA20 EECDH+CHACHA20 EECDH+ECDSA+AESGCM EECDH+AESGCM EECDH+ECDSA+AES256 EECDH+AES256 EECDH+ECDSA+AES128 EECDH+AES128 EECDH+ECDSA+3DES EECDH+3DES EDH+CHACHA20 EDH+AESGCM EDH+AES256 EDH+AES128 EDH+3DES AESGCM AES256 AES128 3DES
tls_preempt_cipherlist = yes
tls_random_bytes = 64
tls_ssl_options = NO_COMPRESSION
virtual_alias_domains = hash:${config_directory}/virtual_alias_domains
virtual_alias_maps = hash:${config_directory}/virtual_alias_maps
virtual_gid_maps = static:5000
virtual_mailbox_base = /var/vmail
virtual_mailbox_domains = hash:${config_directory}/virtual_mailbox_domains
virtual_mailbox_limit = 0
virtual_mailbox_maps = hash:${config_directory}/virtual_mailbox_maps
virtual_minimum_uid = 5000
virtual_transport = dovecot
virtual_uid_maps = static:5000
"EOF"
cat > /etc/postfix/master.cf << "EOF"
#
# Postfix master process configuration file. For details on the format
# of the file, see the master(5) manual page (command: "man 5 master" or
# on-line: http://www.postfix.org/master.5.html).
#
# Do not forget to execute "postfix reload" after editing this file.
#
# ==========================================================================
# service type private unpriv chroot wakeup maxproc command + args
# (yes) (yes) (no) (never) (100)
# ==========================================================================
#smtp inet n - n - - smtpd
smtp inet n - n - 1 postscreen
smtpd pass - - n - - smtpd
dnsblog unix - - n - 0 dnsblog
tlsproxy unix - - n - 0 tlsproxy
submission inet n - n - - smtpd
-o syslog_name=postfix/submission
-o smtpd_tls_security_level=encrypt
# -o smtpd_sasl_auth_enable=yes
# -o smtpd_reject_unlisted_recipient=no
# -o smtpd_client_restrictions=$mua_client_restrictions
# -o smtpd_helo_restrictions=$mua_helo_restrictions
# -o smtpd_sender_restrictions=$mua_sender_restrictions
# -o smtpd_recipient_restrictions=
# -o smtpd_relay_restrictions=permit_sasl_authenticated,reject
-o milter_macro_daemon_name=ORIGINATING
#smtps inet n - n - - smtpd
# -o syslog_name=postfix/smtps
# -o smtpd_tls_wrappermode=yes
# -o smtpd_sasl_auth_enable=yes
# -o smtpd_reject_unlisted_recipient=no
# -o smtpd_client_restrictions=$mua_client_restrictions
# -o smtpd_helo_restrictions=$mua_helo_restrictions
# -o smtpd_sender_restrictions=$mua_sender_restrictions
# -o smtpd_recipient_restrictions=
# -o smtpd_relay_restrictions=permit_sasl_authenticated,reject
# -o milter_macro_daemon_name=ORIGINATING
#628 inet n - n - - qmqpd
pickup unix n - n 60 1 pickup
cleanup unix n - n - 0 cleanup
qmgr unix n - n 300 1 qmgr
#qmgr unix n - n 300 1 oqmgr
tlsmgr unix - - n 1000? 1 tlsmgr
rewrite unix - - n - - trivial-rewrite
bounce unix - - n - 0 bounce
defer unix - - n - 0 bounce
trace unix - - n - 0 bounce
verify unix - - n - 1 verify
flush unix n - n 1000? 0 flush
proxymap unix - - n - - proxymap
proxywrite unix - - n - 1 proxymap
smtp unix - - n - - smtp
relay unix - - n - - smtp
# -o smtp_helo_timeout=5 -o smtp_connect_timeout=5
showq unix n - n - - showq
error unix - - n - - error
retry unix - - n - - error
discard unix - - n - - discard
local unix - n n - - local
virtual unix - n n - - virtual
lmtp unix - - n - - lmtp
anvil unix - - n - 1 anvil
scache unix - - n - 1 scache
#
# ====================================================================
# Interfaces to non-Postfix software. Be sure to examine the manual
# pages of the non-Postfix software to find out what options it wants.
#
# Many of the following services use the Postfix pipe(8) delivery
# agent. See the pipe(8) man page for information about ${recipient}
# and other message envelope options.
# ====================================================================
#
# maildrop. See the Postfix MAILDROP_README file for details.
# Also specify in main.cf: maildrop_destination_recipient_limit=1
#
#maildrop unix - n n - - pipe
# flags=DRhu user=vmail argv=/usr/local/bin/maildrop -d ${recipient}
#
# ====================================================================
#
# Recent Cyrus versions can use the existing "lmtp" master.cf entry.
#
# Specify in cyrus.conf:
# lmtp cmd="lmtpd -a" listen="localhost:lmtp" proto=tcp4
#
# Specify in main.cf one or more of the following:
# mailbox_transport = lmtp:inet:localhost
# virtual_transport = lmtp:inet:localhost
#
# ====================================================================
#
# Cyrus 2.1.5 (Amos Gouaux)
# Also specify in main.cf: cyrus_destination_recipient_limit=1
#
#cyrus unix - n n - - pipe
# user=cyrus argv=/cyrus/bin/deliver -e -r ${sender} -m ${extension} ${user}
#
# ====================================================================
#
# Old example of delivery via Cyrus.
#
#old-cyrus unix - n n - - pipe
# flags=R user=cyrus argv=/cyrus/bin/deliver -e -m ${extension} ${user}
#
# ====================================================================
#
# See the Postfix UUCP_README file for configuration details.
#
#uucp unix - n n - - pipe
# flags=Fqhu user=uucp argv=uux -r -n -z -a$sender - $nexthop!rmail ($recipient)
#
# ====================================================================
#
# Other external delivery methods.
#
#ifmail unix - n n - - pipe
# flags=F user=ftn argv=/usr/lib/ifmail/ifmail -r $nexthop ($recipient)
#
#bsmtp unix - n n - - pipe
# flags=Fq. user=bsmtp argv=/usr/local/sbin/bsmtp -f $sender $nexthop $recipient
#
#scalemail-backend unix - n n - 2 pipe
# flags=R user=scalemail argv=/usr/lib/scalemail/bin/scalemail-store
# ${nexthop} ${user} ${extension}
#
#mailman unix - n n - - pipe
# flags=FR user=list argv=/usr/lib/mailman/bin/postfix-to-mailman.py
# ${nexthop} ${user}
#
dovecot unix - n n - - pipe
flags=DRhu user=vmail:vmail argv=/usr/libexec/dovecot/dovecot-lda
-f ${sender} -a ${recipient} -d ${user}@${nexthop}
"EOF"
cat > /etc/postfix/recipient_checks.pcre << "EOF"
/^\@/ 550 Invalid address format.
/[!%\@].*\@/ 550 This server disallows weird address syntax.
/^postmaster\@/ OK
/^hostmaster\@/ OK
/^security\@/ OK
/^abuse\@/ OK
/^admin\@/ OK
"EOF"
Gruss,
Joe User
Letzte Aktualisierung: 08.04.2017
