# nginx config:

location ~* /[^auth] {
	auth_request /auth;
	auth_request_set $username $upstream_http_x_username;
	auth_request_set $my_error_page $upstream_http_x_error_page;
	add_header X-Set-Username $username;
	# Do your business here
}

location = /auth {
	gzip off;
	auth_request off;
	include fastcgi_params;
	fastcgi_max_temp_file_size 0;
	fastcgi_split_path_info ^((?U).+auth)(/?.+)$;
	fastcgi_pass   unix:/var/run/php5-fpm/php5-fpm.sock;
	#fastcgi_param  HTTP_AUTH_PERMIT_USERS user@domain.tld;
	fastcgi_param  DOCUMENT_ROOT $document_root;
	fastcgi_param  SCRIPT_FILENAME /var/share/www-data/scripts/authentication.php;
	fastcgi_param  SCRIPT_NAME authentication.php;
	fastcgi_param  PATH_INFO   $fastcgi_path_info;

	internal;
}