mirror of
https://github.com/dev-sec/ansible-collection-hardening
synced 2024-11-10 09:14:18 +00:00
Merge pull request #20 from hardening-io/sysctl_restyle
Change sysctl-task. Fix #18
This commit is contained in:
Christoph Hartmann
commit
194ea7497f
2 changed files with 137 additions and 142 deletions
|
|
@ -1,146 +1,25 @@
|
|||
---
|
||||
- name: Disable IPv4 traffic forwarding.
|
||||
sysctl: name='net.ipv4.ip_forward' value=0 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
when: not os_network_forwarding
|
||||
|
||||
- name: Enable IPv4 traffic forwarding again, but only if required.
|
||||
sysctl: name='net.ipv4.ip_forward' value=1 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
when: os_network_forwarding
|
||||
- name: include sysctl variables
|
||||
include_vars: sysctl.yml
|
||||
|
||||
- name: Disable IPv6 traffic forwarding.
|
||||
sysctl: name='net.ipv6.conf.all.forwarding' value=0 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
when: not (os_network_forwarding and os_network_ipv6_enable)
|
||||
|
||||
- name: Enable IPv6 traffic forwarding again, but only if required.
|
||||
sysctl: name='net.ipv6.conf.all.forwarding' value=1 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
when: os_network_forwarding and os_network_ipv6_enable
|
||||
|
||||
- name: ignore RAs on Ipv6
|
||||
sysctl: name='net.ipv6.conf.all.accept_ra' value=0 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
|
||||
- name: ignore RAs on Ipv6
|
||||
sysctl: name='net.ipv6.conf.default.accept_ra' value=0 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
|
||||
- name: Enable RFC-recommended source validation feature.
|
||||
sysctl: name='net.ipv4.conf.all.rp_filter' value=1 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
|
||||
- name: Enable RFC-recommended source validation feature.
|
||||
sysctl: name='net.ipv4.conf.default.rp_filter' value=1 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
|
||||
- name: Reduce the surface on SMURF attacks. Make sure to ignore ECHO broadcasts, which are only required in broad network analysis.
|
||||
sysctl: name='net.ipv4.icmp_echo_ignore_broadcasts' value=1 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
|
||||
- name: There is no reason to accept bogus error responses from ICMP, so ignore them instead.
|
||||
sysctl: name='net.ipv4.icmp_ignore_bogus_error_responses' value=1 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
|
||||
- name: Limit the amount of traffic the system uses for ICMP.
|
||||
sysctl: name='net.ipv4.icmp_ratelimit' value=100 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
|
||||
- name: Adjust the ICMP ratelimit to include ping, dst unreachable, source quench, ime exceed, param problem, timestamp reply, information reply
|
||||
sysctl: name='net.ipv4.icmp_ratemask' value=88089 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
|
||||
- name: Disable IPv6
|
||||
sysctl: name='net.ipv6.conf.all.disable_ipv6' value=1 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
when: not os_network_ipv6_enable
|
||||
|
||||
- name: Enable IPv6 as it is needed.
|
||||
sysctl: name='net.ipv6.conf.all.disable_ipv6' value=0 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
when: os_network_ipv6_enable
|
||||
|
||||
- name: Protect against wrapping sequence numbers at gigabit speeds
|
||||
sysctl: name='net.ipv4.tcp_timestamps' value=0 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
|
||||
- name: Define restriction level for announcing the local source IP
|
||||
sysctl: name='net.ipv4.conf.all.arp_ignore' value=0 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
when: not os_network_arp_restricted
|
||||
|
||||
- name: Define restriction level for announcing the local source IP
|
||||
sysctl: name='net.ipv4.conf.all.arp_ignore' value=1 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
when: os_network_arp_restricted
|
||||
|
||||
- name: Define mode for sending replies in response to received ARP requests that resolve local target IP addresses
|
||||
sysctl: name='net.ipv4.conf.all.arp_announce' value=0 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
when: not os_network_arp_restricted
|
||||
|
||||
- name: Define mode for sending replies in response to received ARP requests that resolve local target IP addresses
|
||||
sysctl: name='net.ipv4.conf.all.arp_announce' value=2 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
when: os_network_arp_restricted
|
||||
|
||||
- name: RFC 1337 fix F1
|
||||
sysctl: name='net.ipv4.tcp_rfc1337' value=1 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
|
||||
- name: Syncookies is used to prevent SYN-flooding attacks.
|
||||
sysctl: name='net.ipv4.tcp_syncookies' value=1 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
|
||||
- sysctl: name='net.ipv4.conf.all.shared_media' value=1 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
- sysctl: name='net.ipv4.conf.default.shared_media' value=1 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
|
||||
- name: Accepting source route can lead to malicious networking behavior, so disable it if not needed.
|
||||
sysctl: name='net.ipv4.conf.all.accept_source_route' value=0 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
|
||||
- name: Accepting source route can lead to malicious networking behavior, so disable it if not needed.
|
||||
sysctl: name='net.ipv4.conf.default.accept_source_route' value=0 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
|
||||
# Accepting redirects can lead to malicious networking behavior, so disable
|
||||
# it if not needed.
|
||||
- sysctl: name='net.ipv4.conf.default.accept_redirects' value=0 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
- sysctl: name='net.ipv4.conf.all.accept_redirects' value=0 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
- sysctl: name='net.ipv4.conf.all.secure_redirects' value=0 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
- sysctl: name='net.ipv4.conf.default.secure_redirects' value=0 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
- sysctl: name='net.ipv6.conf.default.accept_redirects' value=0 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
- sysctl: name='net.ipv6.conf.all.accept_redirects' value=0 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
|
||||
# For non-routers: don't send redirects, these settings are 0
|
||||
- sysctl: name='net.ipv4.conf.all.send_redirects' value=0 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
- sysctl: name='net.ipv4.conf.all.send_redirects' value=0 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
|
||||
- name: log martian packets
|
||||
sysctl: name='net.ipv4.conf.all.log_martians' value=0 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
|
||||
# ipv6 config
|
||||
# NSA 2.5.3.2.5 Limit Network-Transmitted Configuration
|
||||
- sysctl: name='net.ipv6.conf.default.router_solicitations' value=0 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
- sysctl: name='net.ipv6.conf.default.accept_ra_rtr_pref' value=0 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
- sysctl: name='net.ipv6.conf.default.accept_ra_pinfo' value=0 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
- sysctl: name='net.ipv6.conf.default.accept_ra_defrtr' value=0 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
- sysctl: name='net.ipv6.conf.default.autoconf' value=0 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
- sysctl: name='net.ipv6.conf.default.dad_transmits' value=0 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
- sysctl: name='net.ipv6.conf.default.max_addresses' value=1 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
|
||||
|
||||
# This settings controls how the kernel behaves towards module changes at
|
||||
# runtime. Setting to 1 will disable module loading at runtime.
|
||||
# Setting it to 0 is actually never supported.
|
||||
- name: This settings controls how the kernel behaves towards module changes at runtime.
|
||||
sysctl: name='kernel.modules_disabled' value=1 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
when: not os_security_kernel_enable_module_loading
|
||||
|
||||
# Magic Sysrq should be disabled, but can also be set to a safe value if so
|
||||
# desired for physical machines. It can allow a safe reboot if the system hangs
|
||||
# and is a 'cleaner' alternative to hitting the reset button.
|
||||
# The following values are permitted:
|
||||
#
|
||||
# * **0** - disable sysrq
|
||||
# * **1** - enable sysrq completely
|
||||
# * **>1** - bitmask of enabled sysrq functions:
|
||||
# * **2** - control of console logging level
|
||||
# * **4** - control of keyboard (SAK, unraw)
|
||||
# * **8** - debugging dumps of processes etc.
|
||||
# * **16** - sync command
|
||||
# * **32** - remount read-only
|
||||
# * **64** - signalling of processes (term, kill, oom-kill)
|
||||
# * **128** - reboot/poweroff
|
||||
# * **256** - nicing of all RT tasks
|
||||
- sysctl: name='kernel.sysrq' value=0 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
when: not os_security_kernel_enable_sysrq
|
||||
|
||||
- sysctl: name='kernel.sysrq' value='{{ os_security_kernel_secure_sysrq }}' sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
when: os_security_kernel_enable_sysrq
|
||||
|
||||
- name: Prevent core dumps with SUID. These are usually only needed by developers and may contain sensitive information.
|
||||
sysctl: name='fs.suid_dumpable' value=0 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
|
||||
- name: # Prevent core dumps with SUID. These are usually only needed by developers and may contain sensitive information.
|
||||
sysctl: name='fs.suid_dumpable' value=1 sysctl_set=yes state=present reload=yes ignoreerrors=yes
|
||||
when: os_security_kernel_enable_core_dump
|
||||
- name: Change various sysctl-settings, look at the sysctl-vars file for documentation
|
||||
sysctl:
|
||||
name: '{{ item.key }}'
|
||||
value: '{{ item.value }}'
|
||||
sysctl_set: yes
|
||||
state: present
|
||||
reload: yes
|
||||
ignoreerrors: yes
|
||||
with_dict: sysctl_config
|
||||
|
||||
- name: Change various sysctl-settings on rhel-hosts, look at the sysctl-vars file for documentation
|
||||
sysctl:
|
||||
name: '{{ item.key }}'
|
||||
value: '{{ item.value }}'
|
||||
sysctl_set: yes
|
||||
state: present
|
||||
reload: yes
|
||||
ignoreerrors: yes
|
||||
with_dict: sysctl_rhel_config
|
||||
when: ansible_distribution == 'RedHat' or ansible_distribution == 'Fedora' or ansible_distribution == 'CentOS'
|
||||
|
|
|
|||
116
roles/ansible-os-hardening/vars/sysctl.yml
Normal file
116
roles/ansible-os-hardening/vars/sysctl.yml
Normal file
|
|
@ -0,0 +1,116 @@
|
|||
sysctl_config:
|
||||
# Disable IPv4 traffic forwarding.
|
||||
net.ipv4.ip_forward: 0
|
||||
|
||||
# Disable IPv6 traffic forwarding.
|
||||
net.ipv6.conf.all.forwarding: 0
|
||||
|
||||
# ignore RAs on Ipv6.
|
||||
net.ipv6.conf.all.accept_ra: 0
|
||||
net.ipv6.conf.default.accept_ra: 0
|
||||
|
||||
# Enable RFC-recommended source validation feature.
|
||||
net.ipv4.conf.all.rp_filter: 1
|
||||
net.ipv4.conf.default.rp_filter: 1
|
||||
|
||||
# Reduce the surface on SMURF attacks.
|
||||
# Make sure to ignore ECHO broadcasts, which are only required in broad network analysis.
|
||||
net.ipv4.icmp_echo_ignore_broadcasts: 1
|
||||
|
||||
# There is no reason to accept bogus error responses from ICMP, so ignore them instead.
|
||||
net.ipv4.icmp_ignore_bogus_error_responses: 1
|
||||
|
||||
# Limit the amount of traffic the system uses for ICMP.
|
||||
net.ipv4.icmp_ratelimit: 100
|
||||
|
||||
# Adjust the ICMP ratelimit to include ping, dst unreachable,
|
||||
# source quench, ime exceed, param problem, timestamp reply, information reply
|
||||
net.ipv4.icmp_ratemask: 88089
|
||||
|
||||
# Disable IPv6
|
||||
net.ipv6.conf.all.disable_ipv6: 1
|
||||
|
||||
# Protect against wrapping sequence numbers at gigabit speeds
|
||||
net.ipv4.tcp_timestamps: 0
|
||||
|
||||
# Define restriction level for announcing the local source IP
|
||||
net.ipv4.conf.all.arp_ignore: 1
|
||||
|
||||
# Define mode for sending replies in response to
|
||||
# received ARP requests that resolve local target IP addresses
|
||||
net.ipv4.conf.all.arp_announce: 1
|
||||
|
||||
# RFC 1337 fix F1
|
||||
net.ipv4.tcp_rfc1337: 1
|
||||
|
||||
# Syncookies is used to prevent SYN-flooding attacks.
|
||||
net.ipv4.tcp_syncookies: 1
|
||||
|
||||
# Send(router) or accept(host) RFC1620 shared media redirects
|
||||
net.ipv4.conf.all.shared_media: 1
|
||||
net.ipv4.conf.default.shared_media: 1
|
||||
|
||||
# Accepting source route can lead to malicious networking behavior,
|
||||
# so disable it if not needed.
|
||||
net.ipv4.conf.all.accept_source_route: 0
|
||||
|
||||
# Accepting redirects can lead to malicious networking behavior, so disable
|
||||
# it if not needed.
|
||||
net.ipv4.conf.default.accept_redirects: 0
|
||||
net.ipv4.conf.all.accept_redirects: 0
|
||||
net.ipv4.conf.all.secure_redirects: 0
|
||||
net.ipv4.conf.default.secure_redirects: 0
|
||||
net.ipv6.conf.default.accept_redirects: 0
|
||||
net.ipv6.conf.all.accept_redirects: 0
|
||||
|
||||
# For non-routers: don't send redirects, these settings are 0
|
||||
net.ipv4.conf.all.send_redirects: 0
|
||||
net.ipv4.conf.default.send_redirects: 0
|
||||
|
||||
# log martian packets
|
||||
net.ipv4.conf.all.log_martians: 0
|
||||
|
||||
# ipv6 config
|
||||
# NSA 2.5.3.2.5 Limit Network-Transmitted Configuration
|
||||
net.ipv6.conf.default.router_solicitations: 0
|
||||
net.ipv6.conf.default.accept_ra_rtr_pref: 0
|
||||
net.ipv6.conf.default.accept_ra_pinfo: 0
|
||||
net.ipv6.conf.default.accept_ra_defrtr: 0
|
||||
net.ipv6.conf.default.autoconf: 0
|
||||
net.ipv6.conf.default.dad_transmits: 0
|
||||
net.ipv6.conf.default.max_addresses: 1
|
||||
|
||||
# This settings controls how the kernel behaves towards module changes at
|
||||
# runtime. Setting to 1 will disable module loading at runtime.
|
||||
# Setting it to 0 is actually never supported.
|
||||
kernel.modules_disabled: 1
|
||||
|
||||
# Magic Sysrq should be disabled, but can also be set to a safe value if so
|
||||
# desired for physical machines. It can allow a safe reboot if the system hangs
|
||||
# and is a 'cleaner' alternative to hitting the reset button.
|
||||
# The following values are permitted:
|
||||
# * **0** - disable sysrq
|
||||
# * **1** - enable sysrq completely
|
||||
# * **>1** - bitmask of enabled sysrq functions:
|
||||
# * **2** - control of console logging level
|
||||
# * **4** - control of keyboard (SAK, unraw)
|
||||
# * **8** - debugging dumps of processes etc.
|
||||
# * **16** - sync command
|
||||
# * **32** - remount read-only
|
||||
# * **64** - signalling of processes (term, kill, oom-kill)
|
||||
# * **128** - reboot/poweroff
|
||||
# * **256** - nicing of all RT tasks
|
||||
kernel.sysrq: 0
|
||||
|
||||
# Prevent core dumps with SUID. These are usually only
|
||||
# needed by developers and may contain sensitive information.
|
||||
fs.suid_dumpable: 0
|
||||
|
||||
# Virtual memory regions protection
|
||||
kernel.randomize_va_space: 2
|
||||
|
||||
sysctl_rhel_config:
|
||||
# ExecShield protection against buffer overflows
|
||||
kernel.exec-shield: 1
|
||||
|
||||
|
||||
Loading…
Reference in a new issue