# Kernel sysctl configuration file for Red Hat Linux
#
# For binary values, 0 is disabled, 1 is enabled.  See sysctl(8) and
# sysctl.conf(5) for more details.

# Controls IP packet forwarding
net.ipv4.ip_forward = 0

# Controls source route verification
net.ipv4.conf.default.rp_filter = 1

# Do not accept source routing
net.ipv4.conf.default.accept_source_route = 0

# Controls the System Request debugging functionality of the kernel
kernel.sysrq = 0

# Controls whether core dumps will append the PID to the core filename.
# Useful for debugging multi-threaded applications.
kernel.core_uses_pid = 1

# Controls the use of TCP syncookies
net.ipv4.tcp_syncookies = 1

# Disable netfilter on bridges.
net.bridge.bridge-nf-call-ip6tables = 0
net.bridge.bridge-nf-call-iptables = 0
net.bridge.bridge-nf-call-arptables = 0

# Controls the default maxmimum size of a mesage queue
kernel.msgmnb = 65536

# Controls the maximum size of a message, in bytes
kernel.msgmax = 65536

# Controls the maximum shared segment size, in bytes
kernel.shmmax = 68719476736

# Controls the maximum number of shared memory segments, in pages
kernel.shmall = 4294967296
#
# CAP specific modifications
#
# 1.6.1 Restrict Core Dumps
fs.suid_dumpable = 0

# 4.1.2 Disable Send Packet Redirects
net.ipv4.conf.all.send_redirects = 0
net.ipv4.conf.default.send_redirects = 0

# 4.2.1 Disable Source Routed Packet Acceptance
net.ipv4.conf.all.accept_source_route = 0

# 4.2.2 Disable ICMP Redirect Acceptance
net.ipv4.conf.all.accept_redirects = 0
net.ipv4.conf.default.accept_redirects = 0

# 4.2.4 Log Suspicious Packets 
net.ipv4.conf.all.log_martians=1
net.ipv4.conf.default.log_martians=1

# 4.2.5 Enable Ignore Broadcast Requests
net.ipv4.icmp_echo_ignore_broadcasts = 1

# 4.2.6 Enable Bad Error Message Protection
net.ipv4.icmp_ignore_bogus_error_responses = 1

# added security settings
net.ipv4.tcp_max_syn_backlog = 4096
net.ipv4.conf.all.rp_filter = 1
net.ipv4.conf.all.secure_redirects = 0
net.ipv4.conf.default.secure_redirects = 0
net.ipv4.icmp_echo_ignore_all = 0

# 4.4.1 Configure IPv6
net.ipv6.conf.all.accept_ra=0
net.ipv6.conf.default.accept_ra=0

#4.4.1.2 Disable IPv6 Redirect Acceptance
net.ipv6.conf.all.accept_redirects=0
net.ipv6.conf.default.accept_redirects=0