/// <summary>
/// Gets the proxy URI. (IWebProxy interface)
/// </summary>
public Uri GetProxy(Uri uri)
{
if (_proxyHelper.ManualSettingsOnly)
{
return(_proxyUri);
}
var proxyInfo = new Interop.WinHttp.WINHTTP_PROXY_INFO();
try
{
if (_proxyHelper.GetProxyForUrl(_sessionHandle, uri, out proxyInfo))
{
return(GetUriFromString(Marshal.PtrToStringUni(proxyInfo.Proxy)));
}
}
finally
{
Marshal.FreeHGlobal(proxyInfo.Proxy);
Marshal.FreeHGlobal(proxyInfo.ProxyBypass);
}
return(null);
}
/// <summary>
/// Gets the proxy URI. (IWebProxy interface)
/// </summary>
public Uri GetProxy(Uri uri)
{
if (_proxyHelper.ManualSettingsOnly)
{
if (_bypassLocal)
{
IPAddress address = null;
if (uri.IsLoopback)
{
// This is optimization for loopback addresses.
// Unfortunately this does not work for all local addresses.
return(null);
}
// Pre-Check if host may be IP address to avoid parsing.
if (uri.HostNameType == UriHostNameType.IPv6 || uri.HostNameType == UriHostNameType.IPv4)
{
// RFC1123 allows labels to start with number.
// Leading number may or may not be IP address.
// IPv6 [::1] notation. '[' is not valid character in names.
if (IPAddress.TryParse(uri.IdnHost, out address))
{
// Host is valid IP address.
// Check if it belongs to local system.
foreach (IPAddress a in _localIp)
{
if (a.Equals(address))
{
return(null);
}
}
}
}
if (uri.HostNameType != UriHostNameType.IPv6 && uri.IdnHost.IndexOf('.') == -1)
{
// Not address and does not have a dot.
// Hosts without FQDN are considered local.
return(null);
}
}
// Check if we have other rules for bypass.
if (_bypass != null)
{
foreach (Regex entry in _bypass)
{
// IdnHost does not have [].
if (entry.IsMatch(uri.IdnHost))
{
return(null);
}
}
}
// We did not find match on bypass list.
return((uri.Scheme == UriScheme.Https || uri.Scheme == UriScheme.Wss) ? _secureProxyUri : _insecureProxyUri);
}
// For anything else ask WinHTTP.
var proxyInfo = new Interop.WinHttp.WINHTTP_PROXY_INFO();
try
{
if (_proxyHelper.GetProxyForUrl(_sessionHandle, uri, out proxyInfo))
{
return(GetUriFromString(Marshal.PtrToStringUni(proxyInfo.Proxy)));
}
}
finally
{
Marshal.FreeHGlobal(proxyInfo.Proxy);
Marshal.FreeHGlobal(proxyInfo.ProxyBypass);
}
return(null);
}
private void SetRequestHandleProxyOptions(WinHttpRequestState state)
{
// We've already set the proxy on the session handle if we're using no proxy or default proxy settings.
// We only need to change it on the request handle if we have a specific IWebProxy or need to manually
// implement Wininet-style auto proxy detection.
if (state.WindowsProxyUsePolicy == WindowsProxyUsePolicy.UseCustomProxy ||
state.WindowsProxyUsePolicy == WindowsProxyUsePolicy.UseWinInetProxy)
{
var proxyInfo = new Interop.WinHttp.WINHTTP_PROXY_INFO();
bool updateProxySettings = false;
Uri uri = state.RequestMessage.RequestUri;
try
{
if (state.Proxy != null)
{
Debug.Assert(state.WindowsProxyUsePolicy == WindowsProxyUsePolicy.UseCustomProxy);
updateProxySettings = true;
if (state.Proxy.IsBypassed(uri))
{
proxyInfo.AccessType = Interop.WinHttp.WINHTTP_ACCESS_TYPE_NO_PROXY;
}
else
{
proxyInfo.AccessType = Interop.WinHttp.WINHTTP_ACCESS_TYPE_NAMED_PROXY;
Uri proxyUri = state.Proxy.GetProxy(uri);
string proxyString = string.Format(
CultureInfo.InvariantCulture,
"{0}://{1}",
proxyUri.Scheme,
proxyUri.Authority);
proxyInfo.Proxy = Marshal.StringToHGlobalUni(proxyString);
}
}
else if (_proxyHelper != null && _proxyHelper.AutoSettingsUsed)
{
updateProxySettings = true;
_proxyHelper.GetProxyForUrl(_sessionHandle, uri, out proxyInfo);
}
if (updateProxySettings)
{
GCHandle pinnedHandle = GCHandle.Alloc(proxyInfo, GCHandleType.Pinned);
try
{
SetWinHttpOption(
state.RequestHandle,
Interop.WinHttp.WINHTTP_OPTION_PROXY,
pinnedHandle.AddrOfPinnedObject(),
(uint)Marshal.SizeOf(proxyInfo));
}
finally
{
pinnedHandle.Free();
}
}
}
finally
{
Marshal.FreeHGlobal(proxyInfo.Proxy);
Marshal.FreeHGlobal(proxyInfo.ProxyBypass);
}
}
}
/// <summary>
/// Gets the proxy URIs.
/// </summary>
public MultiProxy GetMultiProxy(Uri uri)
{
// We need WinHTTP to detect and/or process a PAC (JavaScript) file. This maps to
// "Automatically detect settings" and/or "Use automatic configuration script" from IE
// settings. But, calling into WinHTTP can be slow especially when it has to call into
// the out-of-process service to discover, load, and run the PAC file. So, we skip
// calling into WinHTTP if there was a recent failure to detect a PAC file on the network.
// This is a common error. The default IE settings on a Windows machine consist of the
// single checkbox for "Automatically detect settings" turned on and most networks
// won't actually discover a PAC file on the network since WPAD protocol isn't configured.
if (_proxyHelper.AutoSettingsUsed && !_proxyHelper.RecentAutoDetectionFailure)
{
Interop.WinHttp.WINHTTP_PROXY_INFO proxyInfo = default;
try
{
if (_proxyHelper.GetProxyForUrl(_sessionHandle, uri, out proxyInfo))
{
// If WinHTTP just specified a Proxy with no ProxyBypass list, then
// we can return the Proxy uri directly.
if (proxyInfo.ProxyBypass == IntPtr.Zero)
{
if (proxyInfo.Proxy != IntPtr.Zero)
{
string proxyStr = Marshal.PtrToStringUni(proxyInfo.Proxy) !;
return(MultiProxy.CreateLazy(_failedProxies, proxyStr, IsSecureUri(uri)));
}
else
{
return(MultiProxy.Empty);
}
}
// A bypass list was also specified. This means that WinHTTP has fallen back to
// using the manual IE settings specified and there is a ProxyBypass list also.
// Since we're not really using the full WinHTTP stack, we need to use HttpSystemProxy
// to do the computation of the final proxy uri merging the information from the Proxy
// and ProxyBypass strings.
}
else
{
return(MultiProxy.Empty);
}
}
finally
{
Marshal.FreeHGlobal(proxyInfo.Proxy);
Marshal.FreeHGlobal(proxyInfo.ProxyBypass);
}
}
// Fallback to manual settings if present.
if (_proxyHelper.ManualSettingsUsed)
{
if (_bypassLocal)
{
IPAddress?address;
if (uri.IsLoopback)
{
// This is optimization for loopback addresses.
// Unfortunately this does not work for all local addresses.
return(MultiProxy.Empty);
}
// Pre-Check if host may be IP address to avoid parsing.
if (uri.HostNameType == UriHostNameType.IPv6 || uri.HostNameType == UriHostNameType.IPv4)
{
// RFC1123 allows labels to start with number.
// Leading number may or may not be IP address.
// IPv6 [::1] notation. '[' is not valid character in names.
if (IPAddress.TryParse(uri.IdnHost, out address))
{
// Host is valid IP address.
// Check if it belongs to local system.
foreach (IPAddress a in _localIp !)
{
if (a.Equals(address))
{
return(MultiProxy.Empty);
}
}
}
}
if (uri.HostNameType != UriHostNameType.IPv6 && !uri.IdnHost.Contains('.'))
{
// Not address and does not have a dot.
// Hosts without FQDN are considered local.
return(MultiProxy.Empty);
}
}
// Check if we have other rules for bypass.
if (_bypass != null)
{
foreach (string entry in _bypass)
{
// IdnHost does not have [].
if (SimpleRegex.IsMatchWithStarWildcard(uri.IdnHost, entry))
{
return(MultiProxy.Empty);
}
}
}
// We did not find match on bypass list.
return(IsSecureUri(uri) ? _secureProxy : _insecureProxy);
}
return(MultiProxy.Empty);
}