#
# Configuration file for setting network variables. Please note these settings
# override /etc/sysctl.conf and /etc/sysctl.d. If you prefer to use
# /etc/sysctl.conf, please adjust IPT_SYSCTL in /etc/default/ufw. See
# Documentation/networking/ip-sysctl.txt in the kernel source code for more
# information.
#

# Disable ICMP redirects. ICMP redirects are rarely used but can be used in
# MITM (man-in-the-middle) attacks. Disabling ICMP may disrupt legitimate
# traffic to those sites.
net/ipv4/conf/all/accept_redirects=0
net/ipv4/conf/default/accept_redirects=0
net/ipv6/conf/all/accept_redirects=0
net/ipv6/conf/default/accept_redirects=0

# Ignore bogus ICMP errors
net/ipv4/icmp_echo_ignore_broadcasts=1
net/ipv4/icmp_ignore_bogus_error_responses=1
net/ipv4/icmp_echo_ignore_all=0

# Don't log Martian Packets (impossible addresses)
# packets
net/ipv4/conf/all/log_martians=0
net/ipv4/conf/default/log_martians=0

net/ipv4/tcp/syncookies=1                    # Enable syn flood protection
net/ipv4/conf/all/accept_source_route=0      # Ignore source-routed packets
net/ipv6/conf/all/accept_source_route=0      # IPv6 - Ignore ICMP redirects
net/ipv4/conf/default/accept_source_route=0  # Ignore source-routed packets
net/ipv6/conf/default/accept_source_route=0  # IPv6 - Ignore source-routed packets
net/ipv4/conf/all/secure_redirects=1         # Ignore ICMP redirects from non-GW hosts
net/ipv4/conf/default/secure_redirects=1     # Ignore ICMP redirects from non-GW hosts
net/ipv4/ip_forward=0                        # Do not allow traffic between networks or act as a router
net/ipv6/conf/all/forwarding=0               # IPv6 - Do not allow traffic between networks or act as a router
net/ipv4/conf/all/send_redirects=0           # Don't allow traffic between networks or act as a router
net/ipv4/conf/default/send_redirects=0       # Don't allow traffic between networks or act as a router
net/ipv4/conf/all/rp_filter=1                # Reverse path filtering - IP spoofing protection
net/ipv4/conf/default/rp_filter=1            # Reverse path filtering - IP spoofing protection
net/ipv4/tcp_rfc1337=1                       # Implement RFC 1337 fix
kernel/randomize_va_space=2                  # Randomize addresses of mmap base, heap, stack and VDSO page
fs/protected_hardlinks=1                     # Provide protection from ToCToU races
fs/protected_symlinks=1                      # Provide protection from ToCToU races
kernel/kptr_restrict=1                       # Make locating kernel addresses more difficult
kernel/perf_event_paranoid=2                 # Set perf only available to root