【web.config】Proxy使用時のIP制限&HOSTヘッダチェック

<security>
    <ipSecurity allowUnlisted="false" denyAction="Forbidden" enableProxyMode="true">
        <!-- Proxy IP-->
        <add allowed="true" ipAddress="xxx.xxx.xxx.xxx" />
        <!-- Source IP -->
        <add allowed="true" ipAddress="xxx.xxx.xxx.xxx" />
    </ipSecurity>
</security>
<rewrite>
    <rules>
        <rule name="HostCheck" stopProcessing="true" enabled="true">
            <match url="(.*)"/>
            <conditions>
                <add input="{HTTP_HOST}" pattern="^xxx\.jp$" negate="true" />
                <add input="{HTTP_HOST}" pattern="^yyy\.net$" negate="true" />
            </conditions>
            <action type="CustomResponse" statusCode="403" />
        </rule>
    </rules>
</rewrite>