Amavis, SpamAssassin, ClamAV
Az Amavis nevű program segítségével tudjuk vizsgálni a leveket, hogy vírusosak, vagy spamnek minősülnek-e.
Telepítjük a szükséges csomagokat
apt-get install amavisd-new spamassassin clamav clamav-daemon zoo unzip bzip2 libnet-ph-perl libnet-snpp-perl libnet-telnet-perl nomarch lzop pax
Először engedélyeznünk kell a Clamavot és a SpamAssassin-t.
nano /etc/amavis/conf.d/15-content_filter_mode
use strict;
# You can modify this file to re-enable SPAM checking through spamassassin
# and to re-enable antivirus checking.
#
# Default antivirus checking mode
# Please note, that anti-virus checking is DISABLED by
# default.
# If You wish to enable it, please uncomment the following lines:
@bypass_virus_checks_maps = (
\%bypass_virus_checks, \@bypass_virus_checks_acl, \$bypass_virus_checks_re);
#
# Default SPAM checking mode
# Please note, that anti-spam checking is DISABLED by
# default.
# If You wish to enable it, please uncomment the following lines:
@bypass_spam_checks_maps = (
\%bypass_spam_checks, \@bypass_spam_checks_acl, \$bypass_spam_checks_re);
1; # ensure a defined return
Most meg kell mondanunk az Amavis-nek, hogy mit tegyen a vírusos /spam mailekkel.
nano /etc/amavis/conf.d/20-debian_defaults
A default beállítások jók
$QUARANTINEDIR = "$MYHOME/virusmails";
$quarantine_subdir_levels = 1; # enable quarantine dir hashing
$log_recip_templ = undef; # disable by-recipient level-0 log entries
$DO_SYSLOG = 1; # log via syslogd (preferred)
$syslog_ident = 'amavis'; # syslog ident tag, prepended to all messages
$syslog_facility = 'mail';
$syslog_priority = 'debug'; # switch to info to drop debug output, etc
$enable_db = 1; # enable use of BerkeleyDB/libdb (SNMP and nanny)
$enable_global_cache = 1; # enable use of libdb-based cache if $enable_db=1
$inet_socket_port = 10024; # default listening socket
$sa_spam_subject_tag = '***SPAM*** ';
$sa_tag_level_deflt = 2.0; # add spam info headers if at, or above that level
$sa_tag2_level_deflt = 6.31; # add 'spam detected' headers at that level
$sa_kill_level_deflt = 6.31; # triggers spam evasive actions
$sa_dsn_cutoff_level = 10; # spam level beyond which a DSN is not sent
[...]
$final_virus_destiny = D_DISCARD; # (data not lost, see virus quarantine)
$final_banned_destiny = D_BOUNCE; # D_REJECT when front-end MTA
$final_spam_destiny = D_BOUNCE;
$final_bad_header_destiny = D_PASS; # False-positive prone (for spam)
nano /etc/amavis/conf.d/50-user
use strict;
#
# Place your configuration directives here. They will override those in
# earlier files.
#
# See /usr/share/doc/amavisd-new/ for documentation and examples of
# the directives you can use in this file
#
$pax='pax';
#------------ Do not modify anything below this line -------------
1; # ensure a defined return
Hozzuk létre a usert hozzá, hogy biztonsággal tudjuk futtatni
adduser clamav amavis
/etc/init.d/amavis restart
/etc/init.d/clamav-freshclam restart
/etc/init.d/clamav-daemon restart
Most meg kell mondanunk a postfixnek, hogy a leveleket az amavis-on keresztül fogadja.
postconf -e 'content_filter = amavis:[127.0.0.1]:10024'
postconf -e 'receive_override_options = no_address_mappings'
A config végére írjuk be:
nano /etc/postfix/master.cf
amavis unix - - - - 2 smtp
-o smtp_data_done_timeout=1200
-o smtp_send_xforward_command=yes
127.0.0.1:10025 inet n - - - - smtpd
-o content_filter=
-o local_recipient_maps=
-o relay_recipient_maps=
-o smtpd_restriction_classes=
-o smtpd_client_restrictions=
-o smtpd_helo_restrictions=
-o smtpd_sender_restrictions=
-o smtpd_recipient_restrictions=permit_mynetworks,reject
-o mynetworks=127.0.0.0/8
-o strict_rfc821_envelopes=yes
-o receive_override_options=no_unknown_recipient_checks,no_header_body_checks
Restart postfix:
/etc/init.d/postfix restart
Razor, Pyzor, DCC
A fenti három alkalmazás spamszűrő, egymással együtt működve.
apt-get install razor pyzor
A DCC nincs benne a repoban, ezért kézzel kell felrakni.
cd /tmp
wget http://www.dcc-servers.net/dcc/source/dcc-dccproc.tar.Z
tar xzvf dcc-dccproc.tar.Z
cd dcc-dccproc-1.3.143
./configure --with-uid=amavis
make
make install
chown -R amavis:amavis /var/dcc
ln -s /var/dcc/libexec/dccifd /usr/local/bin/dccifd
Most meg kell mondani a SpamAssassinnak, hogy használja is őket:
nano /etc/spamassassin/local.cf
#dcc
use_dcc 1
dcc_path /usr/local/bin/dccproc
#pyzor
use_pyzor 1
pyzor_path /usr/bin/pyzor
#razor
use_razor2 1
razor_config /etc/razor/razor-agent.conf
#bayes
use_bayes 1
use_bayes_rules 1
bayes_auto_learn 1
Engedélyezni kell a DCC plugint a SpamAssassinban.
nano /etc/spamassassin/v310.pre
# DCC - perform DCC message checks.
#
# DCC is disabled here because it is not open source. See the DCC
# license for more details.
#
loadplugin Mail::SpamAssassin::Plugin::DCC
Ellenőrizzük, hogy nem írtunk el semmit:
spamassassin --lint
Ha nincs hiba, akkor:
/etc/init.d/amavis restart
Most frissítjük a SpamAssassin szabályokat:
sa-update --no-gpg
Ütemezzük:
crontab -e
23 4 */2 * * /usr/bin/sa-update --no-gpg &> /dev/null
Kvóta értesítések
cd /usr/local/sbin/
[B]nano quota_notify[/B]
#!/usr/bin/perl -w
# Author <jps@tntmax.com>
#
# This script assumes that virtual_mailbox_base in defined
# in postfix's main.cf file. This directory is assumed to contain
# directories which themselves contain your virtual user's maildirs.
# For example:
#
# -----------/
# |
# |
# home/vmail/domains/
# | |
# | |
# example.com/ foo.com/
# |
# |
# -----------------
# | | |
# | | |
# user1/ user2/ user3/
# |
# |
# maildirsize
#
use strict;
my $POSTFIX_CF = "/etc/postfix/main.cf";
my $MAILPROG = "/usr/sbin/sendmail -t";
my $WARNPERCENT = 80;
my @POSTMASTERS = ('postmaster@cimem.hu’);
my $CONAME = 'My Company';
my $COADDR = 'postmaster@cimem.hu';
my $SUADDR = 'postmaster@cimem.hu’;
my $MAIL_REPORT = 1;
my $MAIL_WARNING = 1;
#get virtual mailbox base from postfix config
open(PCF, "< $POSTFIX_CF") or die $!;
my $mboxBase;
while (<PCF>) {
next unless /virtual_mailbox_base\s*=\s*(.*)\s*/;
$mboxBase = $1;
}
close(PCF);
#assume one level of subdirectories for domain names
my @domains;
opendir(DIR, $mboxBase) or die $!;
while (defined(my $name = readdir(DIR))) {
next if $name =~ /^\.\.?$/; #skip '.' and '..'
next unless (-d "$mboxBase/$name");
push(@domains, $name);
}
closedir(DIR);
#iterate through domains for username/maildirsize files
my @users;
chdir($mboxBase);
foreach my $domain (@domains) {
opendir(DIR, $domain) or die $!;
while (defined(my $name = readdir(DIR))) {
next if $name =~ /^\.\.?$/; #skip '.' and '..'
next unless (-d "$domain/$name");
push(@users, {"$name\@$domain" => "$mboxBase/$domain/$name"});
}
}
closedir(DIR);
#get user quotas and percent used
my (%lusers, $report);
foreach my $href (@users) {
foreach my $user (keys %$href) {
my $quotafile = "$href->{$user}/maildirsize";
next unless (-f $quotafile);
open(QF, "< $quotafile") or die $!;
my ($firstln, $quota, $used);
while (<QF>) {
my $line = $_;
if (! $firstln) {
$firstln = 1;
die "Error: corrupt quotafile $quotafile"
unless ($line =~ /^(\d+)S/);
$quota = $1;
last if (! $quota);
next;
}
die "Error: corrupt quotafile $quotafile"
unless ($line =~ /\s*(-?\d+)/);
$used += $1;
}
close(QF);
next if (! $used);
my $percent = int($used / $quota * 100);
$lusers{$user} = $percent unless not $percent;
}
}
#send a report to the postmasters
if ($MAIL_REPORT) {
open(MAIL, "| $MAILPROG");
select(MAIL);
map {print "To: $_\n"} @POSTMASTERS;
print "From: $COADDR\n";
print "Subject: Daily Quota Report.\n";
print "DAILY QUOTA REPORT:\n\n";
print "----------------------------------------------\n";
print "| % USAGE | ACCOUNT NAME |\n";
print "----------------------------------------------\n";
foreach my $luser ( sort { $lusers{$b} <=> $lusers{$a} } keys %lusers ) {
printf("| %3d | %32s |\n", $lusers{$luser}, $luser);
print "---------------------------------------------\n";
}
print "\n--\n";
print "$CONAME\n";
close(MAIL);
}
#email a warning to people over quota
if ($MAIL_WARNING) {
foreach my $luser (keys (%lusers)) {
next unless $lusers{$luser} >= $WARNPERCENT; # skip those under quota
open(MAIL, "| $MAILPROG");
select(MAIL);
print "To: $luser\n";
map {print "BCC: $_\n"} @POSTMASTERS;
print "From: $SUADDR\n";
print "Subject: WARNING: Your mailbox is $lusers{$luser}% full.\n";
print "Reply-to: $SUADDR\n";
print "Your mailbox: $luser is $lusers{$luser}% full.\n\n";
print "Once your e-mail box has exceeded your monthly storage quota\n";
print "your monthly billing will be automatically adjusted.\n";
print "Please consider deleting e-mail and emptying your trash folder to clear some space.\n\n";
print "Contact <$SUADDR> for further assistance.\n\n";
print "Thank You.\n\n";
print "--\n";
print "$CONAME\n";
close(MAIL);
}
}
Ütemezzük:
crontab -e
0 0 * * * /usr/local/sbin/quota_notify &> /dev/null
Ezzel készen is vagyunk, már csak létre kell hozni felhasználókat a MySQL táblákba
Userek hozzáadása
mysql -u root -p
USE mail;
INSERT INTO `domains` (`domain`) VALUES ('domain.com’);
INSERT INTO `users` (`email`, `password`, `quota`) VALUES ('user@domain.com', ENCRYPT('password'), 10485760);
quit;
Ahhoz, hogy létrejöjjön a Maildir és a webmail is működjün küldenünk kell egy levelet az elkészült címre.
apt-get install mailutils
mailx user@domain.com
root@localhost:/usr/local/sbin# mailx user@domain.com
Cc: <-- ENTER
Subject: Welcome <-- ENTER
Welcome! Have fun with your new mail account. <-- ENTER
<-- CTRL+D
root@localhost:/usr/local/sbin#
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