## Block common exploits
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 403;
}

## Block spam
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|blue\spill|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 403;
}

## Block user agents
set $block_user_agents 0;

# 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 ($block_user_agents = 1) {
    return 403;
}