Linux――kernel服务安全设置

文件路径：/etc/sysctl.conf


避免放大攻击

1 net.ipv4.icmp_echo_ignore_broadcasts = 1

开启恶意icmp错误消息保护

1 net.ipv4.icmp_ignore_bogus_error_responses = 1

开启SYN洪水攻击保护

1 net.ipv4.tcp_syncookies = 1


开启并记录欺骗，源路由和重定向包

1 net.ipv4.conf.all.log_martians = 1

2 net.ipv4.conf.default.log_martians = 1


处理无源路由的包

1 net.ipv4.conf.all.accept_source_route = 0

2 net.ipv4.conf.default.accept_source_route = 0



开启反向路径过滤


1 net.ipv4.conf.all.rp_filter = 1

2 net.ipv4.conf.default.rp_filter = 1

确保无人能修改路由表


1 net.ipv4.conf.all.accept_redirects = 0

2 net.ipv4.conf.default.accept_redirects = 0

3 net.ipv4.conf.all.secure_redirects = 0

4 net.ipv4.conf.default.secure_redirects = 0



不充当路由器


1 net.ipv4.ip_forward = 0

2 net.ipv4.conf.all.send_redirects = 0

3 net.ipv4.conf.default.send_redirects = 0



开启execshild


1 kernel.exec-shield = 1

2 kernel.randomize_va_space = 1



IPv6设置


1 net.ipv6.conf.default.router_solicitations = 0

2 net.ipv6.conf.default.accept_ra_rtr_pref = 0

3 net.ipv6.conf.default.accept_ra_pinfo = 0

4 net.ipv6.conf.default.accept_ra_defrtr = 0

5 net.ipv6.conf.default.autoconf = 0

6 net.ipv6.conf.default.dad_transmits = 0

7 net.ipv6.conf.default.max_addresses = 1

优化LB使用的端口增加系统文件描述符限制


1 fs.file-max = 65535



允许更多的PIDs (减少滚动翻转问题); may break some programs 32768


1 kernel.pid_max = 65536



增加系统IP端口限制


1 net.ipv4.ip_local_port_range = 1024 65535



增加TCP最大缓冲区大小


1 net.ipv4.tcp_rmem = 4096 87380 8388608

2 net.ipv4.tcp_wmem = 4096 87380 8388608



增加Linux自动调整TCP缓冲区限制最小，默认和最大可使用的字节数最大值不低于4MB，如果你使用非常高的BDP路径可以设置得更高Tcp窗口等


1 net.core.rmem_max = 8388608

2 net.core.wmem_max = 8388608

3 net.core.netdev_max_backlog = 5000

4 net.ipv4.tcp_window_scaling = 1