IIS 下利用UrlRewriter做图片防盗链

<?xml version="1.0" encoding="UTF-8"?>
<configuration>
    <system.webServer>
        <staticContent>
            <clientCache cacheControlMode="UseMaxAge" cacheControlMaxAge="365.00:00:00" />
        </staticContent>
        <rewrite>
            <rules>
        <rule name="RequestBlockingRule1" enabled="true" stopProcessing="true">
            <match url=".*" />
            <conditions>
            <add input="{HTTP_REFERER}" pattern="^$" negate="true" />
            <add input="{HTTP_REFERER}" matchType="Pattern" pattern="^http://(.*\.)?(test\.com)/.*$" ignoreCase="true" negate="true" />
            <add input="{HTTP_REFERER}" matchType="Pattern" pattern="^http://(.*\.)?(fengzili\.com)/.*$" ignoreCase="true" negate="true" />
            </conditions>
            <action type="CustomResponse" statusCode="404" />
        </rule>
                <rule name="Readme" patternSyntax="ECMAScript" stopProcessing="true">
                    <match url="rm" />
                    <action type="Rewrite" url="readm2e.txt" />
                </rule>
            </rules>
        </rewrite>
    </system.webServer>
</configuration>