防止sql注入最好的办法是对于提交后台的所有数据都进行过滤转义。
对于简单的情况，比如包含单引号' , 分号;, <, >, 等字符可通过rewrite直接重订向到404页面来避免。
用rewrite有个前提需要知道，一般用rewrite进行正则匹配只能匹配到网页的URI，也就是url中?前部分，?以后部分是请求参数。
问号后面的请求参数，在nginx用$query_string表 示，不能在rewrite中匹配到，需要用if判断
例如，对于参数中带有单引号的'进行匹配然后定向到错误页面，
/plus/list.php?tid=19&mid=1124' rewrite ^.*([;'<>]).* /error.html break;
直接写这样的一条重写肯定不会正确匹配，因为rewrite参数只会匹配请求的uri，也就是/plus/list.php部分。
需要使用$query_string 借助if进行判断，如果查询串种包含特殊字符，返回404。
if ( $query_string ~* ".*[;'<>].*" ){
return 404;
}
下面来分享一个配置文件实例：
server {
## 禁SQL注入 Block SQL injections
set $block_sql_injections 0;
if ($query_string ~ “union.*select.*(“) {
set $block_sql_injections 1;
}
if ($query_string ~ “union.*all.*select.*”) {
set $block_sql_injections 1;
}
if ($query_string ~ “concat.*(“) {
set $block_sql_injections 1;
}
if ($block_sql_injections = 1) {
return 444;
}
## 禁掉文件注入
set $block_file_injections 0;
if ($query_string ~ “[a-zA-Z0-9_]=http://”) {
set $block_file_injections 1;
}
if ($query_string ~ “[a-zA-Z0-9_]=(..//?)+”) {
set $block_file_injections 1;
}
if ($query_string ~ “[a-zA-Z0-9_]=/([a-z0-9_.]//?)+”) {
set $block_file_injections 1;
}
if ($block_file_injections = 1) {
return 444;
}
## 禁掉溢出攻击
set $block_common_exploits 0;
if ($query_string ~ “(<|%3C).*script.*(>|%3E)”) {
set $block_common_exploits 1;
}
if ($query_string ~ “GLOBALS(=|[|%[0-9A-Z]{0,2})”) {
set $block_common_exploits 1;
}
if ($query_string ~ “_REQUEST(=|[|%[0-9A-Z]{0,2})”) {
set $block_common_exploits 1;
}
if ($query_string ~ “proc/self/environ”) {
set $block_common_exploits 1;
}
if ($query_string ~ “mosConfig_[a-zA-Z_]{1,21}(=|%3D)”) {
set $block_common_exploits 1;
}
if ($query_string ~ “base64_(en|de)code(.*)”) {
set $block_common_exploits 1;
}
if ($block_common_exploits = 1) {
return 444;
}
## 禁spam字段
set $block_spam 0;
if ($query_string ~ “b(ultram|unicauca|valium|viagra|vicodin|xanax|ypxaieo)b”) {
set $block_spam 1;
}
if ($query_string ~ “b(erections|hoodia|huronriveracres|impotence|levitra|libido)b”) {
set $block_spam 1;
}
if ($query_string ~ “b(ambien|bluespill|cialis|cocaine|ejaculation|erectile)b”) {
set $block_spam 1;
}
if ($query_string ~ “b(lipitor|phentermin|pro[sz]ac|sandyauer|tramadol|troyhamby)b”) {
set $block_spam 1;
}
if ($block_spam = 1) {
return 444;
}
## 禁掉user-agents
set $block_user_agents 0;
# Don't disable wget if you need it to run cron jobs!
#if ($http_user_agent ~ “Wget”) {
# set $block_user_agents 1;
#}
# Disable Akeeba Remote Control 2.5 and earlier
if ($http_user_agent ~ “Indy Library”) {
set $block_user_agents 1;
}
# Common bandwidth hoggers and hacking tools.
if ($http_user_agent ~ “libwww-perl”) {
set $block_user_agents 1;
}
if ($http_user_agent ~ “GetRight”) {
set $block_user_agents 1;
}
if ($http_user_agent ~ “GetWeb!”) {
set $block_user_agents 1;
}
if ($http_user_agent ~ “Go!Zilla”) {
set $block_user_agents 1;
}
if ($http_user_agent ~ “Download Demon”) {
set $block_user_agents 1;
}
if ($http_user_agent ~ “Go-Ahead-Got-It”) {
set $block_user_agents 1;
}
if ($http_user_agent ~ “TurnitinBot”) {
set $block_user_agents 1;
}
if ($http_user_agent ~ “GrabNet”) {
set $block_user_agents 1;
}
if ($http_user_agent ~ "WebBench") {
set $block_user_agents 1;
}
if ($http_user_agent ~ "ApacheBench") {
set $block_user_agents 1;
}
if ($http_user_agent ~ ^$) {
set $block_user_agents 1;
}
if ($http_user_agent ~ "Python-urllib") {
set $block_user_agents 1;
}
if ($block_user_agents = 1) {
return 444;
}
}
