十四、Nginx与PHP安全建议
PHP是流行的服务器端脚本语言之一。如下编辑/etc/php.ini文件：
# Disallow dangerous functions disable_functions = phpinfo, system, mail, exec ## Try to limit resources ## # Maximum execution time of each script, in seconds max_execution_time = 30 # Maximum amount of time each script may spend parsing request data max_input_time = 60 # Maximum amount of memory a script may consume (8MB) memory_limit = 8M # Maximum size of POST data that PHP will accept. post_max_size = 8M # Whether to allow HTTP file uploads. file_uploads = Off # Maximum allowed size for uploaded files. upload_max_filesize = 2M # Do not expose PHP error messages to external users display_errors = Off # Turn on safe mode safe_mode = On # Only allow access to executables in isolated directory safe_mode_exec_dir = php-required-executables-path # Limit external access to PHP environment safe_mode_allowed_env_vars = PHP_ # Restrict PHP information leakage expose_php = Off # Log all errors log_errors = On # Do not register globals for input data register_globals = Off # Minimize allowable PHP post size post_max_size = 1K # Ensure PHP redirects appropriately cgi.force_redirect = 0 # Disallow uploading unless necessary # Enable SQL safe mode sql.safe_mode = On # Avoid Opening remote files allow_url_fopen = Off
十五、如果可能让Nginx运行在一个chroot监狱
把nginx放在一个chroot监狱以减小潜在的非法进入其它目录。你可以使用传统的与nginx一起安装的chroot。如果可能，那使用FreeBSD jails，Xen，OpenVZ虚拟化的容器概念。
十六、在防火墙级限制每个IP的连接数
网络服务器必须监视连接和每秒连接限制。PF和Iptales都能够在进入你的nginx服务器之前阻止最终用户的访问。
Linux Iptables:限制每次Nginx连接数
下面的例子会阻止来自一个IP的60秒钟内超过15个连接端口80的连接数。
/sbin/iptables -A INPUT -p tcp –dport 80 -i eth0 -m state –state NEW -m recent –set /sbin/iptables -A INPUT -p tcp –dport 80 -i eth0 -m state –state NEW -m recent –update –seconds 60 –hitcount 15 -j DROP service iptables save
请根据你的具体情况来设置限制的连接数。
十七、配置操作系统保护Web服务器
像以上介绍的启动SELinux.正确设置/nginx文档根目录的权限。Nginx以用户nginx运行。但是根目录（/nginx或者/usr /local/nginx/html）不应该设置属于用户nginx或对用户nginx可写。找出错误权限的文件可以使用如下命令：
find /nginx -user nginx find /usr/local/nginx/html -user nginx
确保你更所有权为root或其它用户，一个典型的权限设置 /usr/local/nginx/html/
ls -l /usr/local/nginx/html/
示例输出：
-rw-r–r– 1 root root 925 Jan 3 00:50 error4xx.html -rw-r–r– 1 root root 52 Jan 3 10:00 error5xx.html -rw-r–r– 1 root root 134 Jan 3 00:52 index.html
