Voici ce que je fais avec Red Hat Enterprise (RHEL).
RHEL dispose d'un iptables
service qui charge les règles /etc/sysconfig/iptables
et je travaille à la modification de ce fichier et au redémarrage du service iptables. Beaucoup de gens aiment déposer des fragments dans un répertoire iptables.d et construire un ensemble de règles iptables (via make ou quelque chose comme ça) à partir de cela. J'inclus des trucs pour reconstruire le jeu de règles par défaut, mais cela ne fait généralement rien. Si vos besoins sont simples, vous pouvez simplement copier un fichier iptables sur le système.
Malgré à quel point cela semble laid, il est assez minutieusement testé sur RHEL4, RHEL5 et RHEL6.
J'ai eu cela avant que le soutien augeas ne soit en marionnette. Si je l'écrivais à nouveau aujourd'hui, je regarderais l'objectif d'augeas iptables avant d'y recourir exec { "perl ...": }
.
Quelques définitions globales pour l'édition des fichiers en place
# Ensure that the line "line" exists in "file":
# Usage:
# append_if_no_such_line { dummy_modules:
# file => "/etc/modules",
# line => dummy
# }
#
define append_if_no_such_line($file, $line, $refreshonly = 'false') {
exec { "/bin/echo '$line' >> '$file'":
unless => "/bin/grep -Fxqe '$line' '$file'",
refreshonly => $refreshonly,
}
}
# Ensure that the line "line" exists in "file":
# Usage:
# prepend_if_no_such_line { dummy_modules:
# file => "/etc/modules",
# line => dummy
# }
#
define prepend_if_no_such_line($file, $line, $refreshonly = 'false') {
$line_no_slashes = slash_escape($line)
exec { "/usr/bin/perl -p0i -e 's/^/$line_no_slashes\n/;' '$file'":
unless => "/bin/grep -Fxqe '$line' '$file'",
refreshonly => $refreshonly,
}
}
define insert_line_after_if_no_such_line($file, $line, $after) {
$line_no_slashes = slash_escape($line)
$after_no_slashes = slash_escape($after)
exec { "/usr/bin/perl -p0i -e 's/^($after_no_slashes)\$/\$1\n$line_no_slashes/m' '$file'":
onlyif => "/usr/bin/perl -ne 'BEGIN { \$ret = 0; } \$ret = 1 if /^$line_no_slashes/; END { exit \$ret; }' '$file'",
}
}
define insert_line_before_if_no_such_line($file, $line, $beforeline) {
$line_no_slashes = slash_escape($line)
$before_no_slashes = slash_escape($beforeline)
exec { "/usr/bin/perl -p0i -e 's/^($before_no_slashes)\$/$line_no_slashes\n\$1/m' '$file'":
onlyif => "/usr/bin/perl -ne 'BEGIN { \$ret = 0; } \$ret = 1 if /^$line_no_slashes/; END { exit \$ret; }' '$file'",
}
}
Ma classe iptables:
class iptables {
if $lsbmajdistrelease >= '6' {
$primarychain = 'INPUT'
} else {
$primarychain = 'RH-Firewall-1-INPUT'
}
package {
iptables:
ensure => installed # "latest" would be too much
}
service {
iptables:
enable => true, # default on
ensure => running, # start it up if it's stopped
hasstatus => true, # since there's no daemon
}
file {
"/etc/sysconfig/iptables":
ensure => present;
}
##
# Build up a config if it's missing components we expect; should
# automatically repair a config if it's broken for really simple reasons
##
# Very first thing: a comment at the top warning about our evil; add even if
# we're not touching anything else...
prepend_if_no_such_line {
"/etc/sysconfig/iptables comment":
file => "/etc/sysconfig/iptables",
line => "# This file partially managed by puppet; attempts to edit will result in magic reappearances"
}
# start
# *filter
insert_line_after_if_no_such_line {
"/etc/sysconfig/iptables *filter":
file => "/etc/sysconfig/iptables",
line => "\\*filter",
after => "#.*",
notify => Service[iptables],
}
# first default chain
# :INPUT ACCEPT [0:0]
insert_line_after_if_no_such_line {
"/etc/sysconfig/iptables:INPUT":
file => "/etc/sysconfig/iptables",
line => ":INPUT ACCEPT \\[0:0\\]",
after => "\\*filter",
notify => Service[iptables],
}
# second default chain
# :FORWARD ACCEPT [0:0]
insert_line_after_if_no_such_line {
"/etc/sysconfig/iptables:FORWARD":
file => "/etc/sysconfig/iptables",
line => ":FORWARD ACCEPT \\[0:0\\]",
after => ":INPUT ACCEPT \\[\\d+:\\d+\\]",
notify => Service[iptables],
}
# third default chain
# :OUTPUT ACCEPT [0:0]
insert_line_after_if_no_such_line {
"/etc/sysconfig/iptables:OUTPUT":
file => "/etc/sysconfig/iptables",
line => ":OUTPUT ACCEPT \\[0:0\\]",
after => ":FORWARD ACCEPT \\[\\d+:\\d+\\]",
notify => Service[iptables],
}
if $lsbmajdistrelease <= 5 {
# Finally, the RH special chain
# :RH-Firewall-1-INPUT - [0:0]
insert_line_after_if_no_such_line {
"/etc/sysconfig/iptables:RH-Firewall-1-INPUT":
file => "/etc/sysconfig/iptables",
line => ":RH-Firewall-1-INPUT - \\[0:0\\]",
after => ":OUTPUT ACCEPT \\[\\d+:\\d+\\]",
notify => Service[iptables],
}
# redirect INPUT to RH chain
# -A INPUT -j RH-Firewall-1-INPUT
insert_line_after_if_no_such_line {
"/etc/sysconfig/iptables:INPUT:RH-Firewall-1-INPUT":
file => "/etc/sysconfig/iptables",
line => "-A INPUT -j RH-Firewall-1-INPUT",
after => ":RH-Firewall-1-INPUT - \\[\\d+:\\d+\\]",
notify => Service[iptables],
}
# redirect FORWARD to RH chain
# -A FORWARD -j RH-Firewall-1-INPUT
insert_line_after_if_no_such_line {
"/etc/sysconfig/iptables:FORWARD:RH-Firewall-1-INPUT":
file => "/etc/sysconfig/iptables",
line => "-A FORWARD -j RH-Firewall-1-INPUT",
after => "-A INPUT -j RH-Firewall-1-INPUT",
notify => Service[iptables],
}
}
# Let anything on localhost work...
# -A $primarychain -i lo -j ACCEPT
insert_line_after_if_no_such_line {
"/etc/sysconfig/iptables:$primarychain lo":
file => "/etc/sysconfig/iptables",
line => "-A $primarychain -i lo -j ACCEPT",
after => "-A FORWARD -j $primarychain",
notify => Service[iptables],
}
# And let through all the ICMP stuff:
# -A $primarychain -p icmp --icmp-type any -j ACCEPT
if $lsbmajdistrelease >= '6' {
insert_line_after_if_no_such_line {
"/etc/sysconfig/iptables:$primarychain icmp":
file => "/etc/sysconfig/iptables",
line => "-A $primarychain -p icmp -j ACCEPT",
after => "-A $primarychain -i lo -j ACCEPT",
notify => Service[iptables],
}
} else {
insert_line_after_if_no_such_line {
"/etc/sysconfig/iptables:$primarychain icmp":
file => "/etc/sysconfig/iptables",
line => "-A $primarychain -p icmp --icmp-type any -j ACCEPT",
after => "-A $primarychain -i lo -j ACCEPT",
notify => Service[iptables],
}
}
# Finally, let anything that's part of an exisiting connection through:
# -A $primarychain -m state --state ESTABLISHED,RELATED -j ACCEPT
insert_line_after_if_no_such_line {
"/etc/sysconfig/iptables:ESTABLISHED":
file => "/etc/sysconfig/iptables",
line => "-A $primarychain -m state --state ESTABLISHED,RELATED -j ACCEPT",
after => "-A $primarychain -p icmp --icmp-type any -j ACCEPT",
notify => Service[iptables],
}
# Very last thing:
# COMMIT
append_if_no_such_line {
"/etc/sysconfig/iptables:COMMIT":
file => "/etc/sysconfig/iptables",
line => "COMMIT",
notify => Service[iptables],
}
# Next to last thing: reject!
# -A $primarychain -j REJECT --reject-with icmp-host-prohibited
insert_line_before_if_no_such_line {
"/etc/sysconfig/iptables:final reject":
file => "/etc/sysconfig/iptables",
line => "-A $primarychain -j REJECT --reject-with icmp-host-prohibited",
beforeline => "COMMIT",
notify => Service[iptables],
}
}
# example:
# iptable_rule { "iptable:ssh":
# rule => "-m state --state NEW -m tcp -p tcp --dport 22 -j ACCEPT"
# }
# change your mind about a rule, do this:
# iptable_rule { "iptable:ssh":
# rule => "-m state --state NEW -m tcp -p tcp --dport 22 -j ACCEPT",
# ensure => "absent",
# }
define iptable_rule($rule, $ensure = 'present') {
if $lsbmajdistrelease >= '6' {
$primarychain = 'INPUT'
} else {
$primarychain = 'RH-Firewall-1-INPUT'
}
$iptablesline = "-A $primarychain $rule"
case $ensure {
default: { err ( "unknown ensure value $ensure" ) }
present: {
insert_line_before_if_no_such_line {
"/etc/sysconfig/iptables:add $rule":
file => "/etc/sysconfig/iptables",
line => $iptablesline,
beforeline => "-A $primarychain -j REJECT --reject-with icmp-host-prohibited",
notify => Service[iptables],
}
}
absent: {
delete_lines {
"/etc/sysconfig/iptables:remove $rule":
file => "/etc/sysconfig/iptables",
pattern => $iptablesline,
notify => Service[iptables],
}
}
}
}
# Example:
# iptable_tcp_port { "iptable:ssh":
# port => "22",
# }
# Example:
# iptable_tcp_port { "iptable:oracle:130.157.5.0/24":
# port => "1521",
# source => "130.157.5.0/24",
# }
# (add ensure => "absent" to remove)
define iptable_tcp_port($port, $ensure = 'present', $source = 'ANY') {
case $source {
"ANY": {
iptable_rule {
"iptable_tcp_port:$port":
rule => "-m state --state NEW -m tcp -p tcp --dport $port -j ACCEPT",
ensure => $ensure,
}
}
default: {
iptable_rule {
"iptable_tcp_port:$port:$source":
rule => "-m state --state NEW -m tcp -p tcp --source $source --dport $port -j ACCEPT",
ensure => $ensure,
}
}
}
}
# Example:
# iptable_udp_port { "iptable:ntp":
# port => "123",
# }
# (again, ensure => "absent" if needed)
define iptable_udp_port($port, $ensure = 'present', $source = 'ANY') {
case $source {
"ANY": {
iptable_rule {
"iptable_udp_port:$port":
rule => "-p udp -m udp --dport $port -j ACCEPT",
ensure => $ensure,
}
}
default: {
iptable_rule {
"iptable_udp_port:$port":
rule => "-p udp -m udp --source $source --dport $port -j ACCEPT",
ensure => $ensure,
}
}
}
}
Quelques exemples d'utilisation dans d'autres classes:
class ssh {
include iptables
iptable_tcp_port {
"iptables:ssh":
port => "22",
ensure => "present"
}
}
class ssh_restricted inherits ssh {
Iptable_tcp_port["iptables:ssh"]{ensure => "absent"}
iptable_tcp_port {
"ssh:RESTRICTED":
port => "22",
source => "X.Y.0.0/16",
ensure => "present";
}
}
class apache {
iptable_tcp_port {
"iptables:http":
require => Service["httpd"],
port => "80";
}
}
class apache::secure {
iptable_tcp_port {
"iptables:https":
require => Service["httpd"],
port => "443";
}
}
class snmp {
iptable_udp_port { "iptables:snmp": port => "161" }
}