/// <summary>
/// Removes verbose data from the constructed instance.
/// </summary>
public override void TrimExcessData()
{
ApplicableDomains.Clear();
ExceptionDomains.Clear();
OriginalRule = string.Empty;
}
/// <summary>
/// Determines whether or not this filter is a match for the supplied HTTP request/response.
/// </summary>
/// <param name="uri">
/// The URI to check against for a match.
/// </param>
/// <param name="rawHeaders">
/// The headers for the request/response we're checking to see if we match against. These may
/// modify the capability to match depending on their content, such as content-type, etc.
/// </param>
/// <returns>
/// True if this filter is a positive match against the supplied URI, false otherwise.
/// </returns>
public bool IsMatch(Uri uri, NameValueCollection rawHeaders)
{
// Make sure that the headers match up with our options.
if (this.Options != UrlFilterOptions.None)
{
string headerVal = null;
long xmlHttpRequestBits = ((OptionsLong & (long)UrlFilterOptions.ExceptXmlHttpRequest) | (OptionsLong & (long)UrlFilterOptions.XmlHttpRequest));
if ((headerVal = rawHeaders.Get("X-Requested-With")) != null)
{
if (headerVal.EqualsAtICase("XMLHttpRequest", 0))
{
xmlHttpRequestBits &= ~(long)UrlFilterOptions.XmlHttpRequest;
}
else
{
xmlHttpRequestBits &= ~(long)UrlFilterOptions.ExceptXmlHttpRequest;
}
}
if (xmlHttpRequestBits != 0)
{
// XML HttpRequest bits were not cleared, meaning that one of those options was
// not satisifed.
return(false);
}
long thirdPartyBits = ((OptionsLong & (long)UrlFilterOptions.ThirdParty) | (OptionsLong & (long)UrlFilterOptions.ExceptThirdParty));
if ((headerVal = rawHeaders.Get("Referer")) != null)
{
if (Uri.TryCreate(headerVal, UriKind.RelativeOrAbsolute, out Uri refererUri))
{
string hostWithoutWww = refererUri.Host;
if (hostWithoutWww.StartsWithQuick("www."))
{
hostWithoutWww = hostWithoutWww.Substring(4);
}
if (hostWithoutWww.EqualsAtICase(uri.Host, 0))
{
thirdPartyBits &= ~(long)UrlFilterOptions.ExceptThirdParty;
}
else
{
thirdPartyBits &= ~(long)UrlFilterOptions.ThirdParty;
}
if (ApplicableDomains.Count > 0 && !ApplicableDomains.Contains(hostWithoutWww))
{
return(false);
}
if (ExceptionDomains.Count > 0 && ExceptionDomains.Contains(hostWithoutWww))
{
return(false);
}
// While we have the referer field, let's go ahead and check if we have
// referer options and if we do or don't have a match.
//
// This is a shortcut. We unfortunately need to also execute this code also
// when there are no options.
if (ApplicableReferers.Count > 0 && !ApplicableReferers.Contains(hostWithoutWww))
{
return(false);
}
if (ExceptReferers.Count > 0 && ExceptReferers.Contains(hostWithoutWww))
{
return(false);
}
}
}
else
{
// The "Referer" field can be omitted when it's a brand new browser request/fresh
// browser context, meaning that this request is not third party in the least
// bit. So, we clear this bit in this special case.
thirdPartyBits &= ~(long)UrlFilterOptions.ExceptThirdParty;
}
if (thirdPartyBits != 0)
{
// Third party bits not cleared, meaning that one of those options was not satisifed.
return(false);
}
long contentTypeBits = ((OptionsLong & (long)UrlFilterOptions.Image) | (OptionsLong & (long)UrlFilterOptions.Script) | (OptionsLong & (long)UrlFilterOptions.StyleSheet) | (OptionsLong & (long)UrlFilterOptions.ExceptImage) | (OptionsLong & (long)UrlFilterOptions.ExceptScript) | (OptionsLong & (long)UrlFilterOptions.ExceptStyleSheet));
if ((headerVal = rawHeaders.Get("Content-Type")) != null)
{
if (headerVal.IndexOfQuick("script") != -1)
{
contentTypeBits &= ~(long)UrlFilterOptions.Script;
}
else
{
contentTypeBits &= ~(long)UrlFilterOptions.ExceptScript;
if (headerVal.IndexOfQuick("image") != -1)
{
contentTypeBits &= ~(long)UrlFilterOptions.Image;
}
else
{
contentTypeBits &= ~(long)UrlFilterOptions.ExceptImage;
if (headerVal.IndexOfQuick("css") != -1)
{
contentTypeBits &= ~(long)UrlFilterOptions.StyleSheet;
}
else
{
contentTypeBits &= ~(long)UrlFilterOptions.ExceptStyleSheet;
}
}
}
}
if (contentTypeBits != 0)
{
// XML HttpRequest bits were not cleared, meaning that one of those options was
// not satisifed.
return(false);
}
}
else
{
if (ApplicableReferers.Count > 0 || ExceptReferers.Count > 0)
{
string headerVal = null;
if ((headerVal = rawHeaders.Get("Referer")) != null)
{
if (Uri.TryCreate(headerVal, UriKind.RelativeOrAbsolute, out Uri refererUri))
{
string hostWithoutWww = refererUri.Host;
if (hostWithoutWww.StartsWithQuick("www."))
{
hostWithoutWww = hostWithoutWww.Substring(4);
}
if (ApplicableReferers.Count > 0 && !ApplicableReferers.Contains(hostWithoutWww))
{
return(false);
}
if (ExceptReferers.Count > 0 && ExceptReferers.Contains(hostWithoutWww))
{
return(false);
}
}
}
}
}
if (ApplicableDomains.Count > 0 || ExceptionDomains.Count > 0)
{
string hostWithoutWww = uri.Host;
if (hostWithoutWww.StartsWithQuick("www."))
{
hostWithoutWww = hostWithoutWww.Substring(4);
}
if (ApplicableDomains.Count > 0 && !ApplicableDomains.Contains(hostWithoutWww))
{
return(false);
}
if (ExceptionDomains.Count > 0 && ExceptionDomains.Contains(hostWithoutWww))
{
return(false);
}
}
int matchIndex = 0;
foreach (var part in Parts)
{
matchIndex = part.IsMatch(uri, matchIndex);
if (matchIndex == -1)
{
return(false);
}
}
// If all parts were found, then this match was a success.
return(true);
}
