static StateContainer SetupContainer()
{
StateContainer props = new StateContainer();
new Xrds(props);
new Yadis(props);
new Html(props);
new IdentityAuthentication(props);
return props;
}
/// <summary>
/// Returns the URL to which the User Agent should be redirected for the initial authentication request.
/// </summary>
/// <param name="props">RequestProperties object holding the current state.</param>
/// <param name="discResult">The DiscoveryResult object created from the previous discovery process.</param>
/// <param name="immediate">Whether or not an Immediate Mode request is being generated.</param>
/// <returns>The complete URL to which the User Agent should be redirected.</returns>
internal static Uri GetRedirectURL(StateContainer props, DiscoveryResult discResult, bool immediate)
{
if (props == null) { throw new ArgumentNullException("props"); }
if (discResult == null) { throw new ArgumentNullException("discResult"); }
NameValueCollection pms = new NameValueCollection();
if (immediate)
{
pms["openid.mode"] = "checkid_immediate";
}
else
{
pms["openid.mode"] = "checkid_setup";
}
string returl = props.ReturnToUrl.AbsoluteUri;
switch (props.AuthMode)
{
case AuthenticationMode.Stateful:
Association assoc = props.AssociationManager.FindByServer(discResult.ServerUrl.AbsoluteUri);
Random r = new Random();
props.Nonce = r.Next();
switch (discResult.AuthVersion)
{
case ProtocolVersion.V1Dot1:
pms["openid.assoc_handle"] = assoc.Handle;
pms["openid.trust_root"] = props.TrustRoot;
break;
case ProtocolVersion.V2Dot0:
pms["openid.ns"] = ProtocolUri.OpenId2Dot0.AbsoluteUri;
pms["openid.assoc_handle"] = assoc.Handle;
pms["openid.realm"] = props.TrustRoot;
break;
}
break;
case AuthenticationMode.Stateless:
switch (discResult.AuthVersion)
{
case ProtocolVersion.V1Dot1:
pms["openid.trust_root"] = props.TrustRoot;
break;
case ProtocolVersion.V2Dot0:
pms["openid.ns"] = ProtocolUri.OpenId2Dot0.AbsoluteUri;
pms["openid.realm"] = props.TrustRoot;
break;
}
break;
}
foreach (IExtension e in props.ExtensionPlugIns)
{
NameValueCollection authdata = e.BuildAuthorizationData(discResult);
foreach (string key in authdata.Keys)
{
if (key == "esoid.ReturnUrl")
{
if (returl.Contains("?"))
{
returl += "&" + authdata[key];
}
else
{
returl += "?" + authdata[key];
}
}
else
{
pms[key] = authdata[key];
}
}
}
pms["openid.return_to"] = Utility.AddExtraVariables(returl, props);
return Utility.MakeGetURL(discResult.ServerUrl, pms);
}
/// <summary>
/// Validate a stateless mode response from an OpenID Provider.
/// </summary>
/// <param name="server">The OpenID Provider</param>
/// <param name="fallback">Whether or not this is a fallback check due to a failed stateful validation attempt.</param>
/// <param name="rp">The StateContainer object containing the arguments to process.</param>
/// <returns>True if the validation is successful, false if not.</returns>
internal static bool ValidateStatelessResponse(Uri server, bool fallback, StateContainer rp)
{
if (server == null) { throw new ArgumentNullException("server"); }
if (rp == null) { throw new ArgumentNullException("rp"); }
NameValueCollection pms = new NameValueCollection();
if (fallback)
{
if (!String.IsNullOrEmpty(rp.RequestArguments["openid.invalidate_handle"]))
{
pms["openid.invalidate_handle"] = rp.RequestArguments["openid.invalidate_handle"];
}
}
// Run validation checks in each plug-in
foreach (IExtension ext in rp.ExtensionPlugIns)
{
if (!ext.Validation()) { return false; }
}
// Send only required parameters to confirm validity
string[] arr_signed = rp.RequestArguments["openid.signed"].Split(',');
for (int i = 0; i < arr_signed.Length; i++)
{
string s = arr_signed[i];
string c = rp.RequestArguments["openid." + arr_signed[i]];
pms["openid." + s] = c;
}
if (server == null)
{
Tracer.Write("No OpenID servers found");
rp.ErrorState = ErrorCondition.NoServersFound;
return false;
}
pms["openid.mode"] = "check_authentication";
pms["openid.assoc_handle"] = rp.RequestArguments["openid.assoc_handle"];
pms["openid.signed"] = rp.RequestArguments["openid.signed"];
pms["openid.sig"] = rp.RequestArguments["openid.sig"];
string actualLocation = null;
// Connect to IdP
string response = Utility.MakeRequest(server, "POST", pms, out actualLocation);
if (String.IsNullOrEmpty(response))
{
Tracer.Write("No response from Identity Provider using POST, trying GET.");
response = Utility.MakeRequest(server, "GET", pms, out actualLocation);
if (String.IsNullOrEmpty(response))
{
return false;
}
}
// Parse reponse
NameValueCollection data = Utility.SplitResponse(response);
// Check for validity of authentication request
if (data["is_valid"] == "true")
{
Tracer.Write("Server has validated authentication response.");
return true;
}
else
{
StringBuilder sb = new StringBuilder();
foreach (string key in data.Keys)
{
sb.AppendLine(key + ":" + data[key]);
}
Tracer.Write("Server has not validated authentication response. Response received: " + sb.ToString());
rp.ErrorState = ErrorCondition.RequestRefused;
return false;
}
}
/// <summary>
/// Validate a stateful mode response from an OpenID Provider.
/// </summary>
/// <param name="server">The OpenID Provider URL.</param>
/// <param name="rp">The StateContainer object needed to process the validation.</param>
/// <returns>Whether or not validation was successful.</returns>
internal static bool ValidateStatefulResponse(Uri server, StateContainer rp)
{
if (server == null) { throw new ArgumentNullException("server"); }
if (rp == null) { throw new ArgumentNullException("rp"); }
if (rp.Nonce == -1)
{
Tracer.Write("Error: The cnonce is not valid.");
rp.ErrorState = ErrorCondition.SessionTimeout;
return false;
}
else
{
if (!String.IsNullOrEmpty(rp.RequestArguments["cnonce"]) && rp.Nonce != Convert.ToInt32(rp.RequestArguments["cnonce"], CultureInfo.InvariantCulture))
{
Tracer.Write("Error: The cnonce has expired.");
rp.ErrorState = ErrorCondition.SessionTimeout;
return false;
}
}
// Run validation checks in each plug-in
foreach (IExtension ext in rp.ExtensionPlugIns)
{
if (!ext.Validation()) { return false; }
}
Tracer.Write("Looking up association in association table.");
Association assoc = rp.AssociationManager.FindByHandle(rp.RequestArguments["openid.assoc_handle"]);
if (assoc == null)
{
// Check to see if the handle has been invalidated
if (rp.RequestArguments["openid.invalidate_handle"] != null)
{
Tracer.Write("Association handle has been invalidated.");
return false;
}
else
{
Tracer.Write("Association handle was not found in the table.");
return false;
}
}
// Ensure association key has not expired
if (assoc.Expiration < DateTime.UtcNow)
{
Tracer.Write("Association has expired, removing from table.");
rp.AssociationManager.Remove(assoc);
return false;
}
// Check for someone trying to forge a response from another
// OpenID Provider
if (server.AbsoluteUri != assoc.Server)
{
Tracer.Write("Received response handle is not valid for the specified OpenID Provider.");
return false;
}
// Compare data from browser to association handle from server
if (assoc.Handle == rp.RequestArguments["openid.assoc_handle"])
{
string[] tokens = rp.RequestArguments["openid.signed"].ToString().Split(',');
string token_contents = "";
foreach (string token in tokens)
{
token_contents += token + ":" + rp.RequestArguments["openid." + token] + "\n";
}
Tracer.Write("Generating signature for tokens: " + token_contents);
string sig = rp.RequestArguments["openid.sig"].ToString();
byte[] secretkey = assoc.Secret;
byte[] tokenbyte = ASCIIEncoding.ASCII.GetBytes(token_contents);
HashAlgorithm hmac = null;
if (assoc.AssociationType == "HMAC-SHA1")
{
hmac = new HMACSHA1(secretkey);
}
else if (assoc.AssociationType == "HMAC-SHA256")
{
hmac = new HMACSHA256(secretkey);
}
byte[] realHash = hmac.ComputeHash(tokenbyte);
string strrealHash = Convert.ToBase64String(realHash);
Tracer.Write("Expected signature: " + sig);
Tracer.Write("Generated signature: " + strrealHash);
if (sig != strrealHash)
{
Tracer.Write("Received signature does not match generated signature");
return false;
}
return true;
}
Tracer.Write("Received association handle does not match cached handle.");
return false;
}
/// <summary>
/// Processes errors received during HTTP requests.
/// </summary>
/// <param name="response">WebResponse object to handle.</param>
/// <param name="rp">StateContainer object where error state will be recorded.</param>
internal static void HandleHttpError(WebResponse response, StateContainer rp)
{
Stream s;
StreamReader sr;
string body = "";
if (response == null)
{
Tracer.Write("Error: Received null response to HTTP request.");
if (rp != null) rp.ErrorState = ErrorCondition.HttpError;
return;
}
HttpWebResponse hwr = (HttpWebResponse)response;
switch (hwr.StatusCode)
{
case HttpStatusCode.BadRequest:
s = response.GetResponseStream();
sr = new StreamReader(s);
body = sr.ReadToEnd();
if (body != null)
{
NameValueCollection data = SplitResponse(body);
if (data["error"] != null)
{
Tracer.Write("Received error: " + data["error"]);
if (rp != null) rp.ErrorState = ErrorCondition.RequestRefused;
return;
}
}
if (rp != null) rp.ErrorState = ErrorCondition.HttpError;
break;
default:
Tracer.Write("HTTP request failed, response code: " + hwr.StatusCode.ToString());
break;
}
}
/// <summary>
/// Appends the cnonce variable to the end of a URL.
/// </summary>
/// <param name="url">URL to process.</param>
/// <param name="rp">StateContainer to use.</param>
/// <returns>A combined URL.</returns>
internal static string AddExtraVariables(string url, StateContainer rp)
{
if (String.IsNullOrEmpty(url)) { return url; }
if (rp == null) { throw new ArgumentNullException("rp"); }
string retval = url;
if (rp.AuthMode == AuthenticationMode.Stateful)
{
if (retval.Contains("?"))
{
retval += "&cnonce=" + rp.Nonce;
}
else
{
retval += "?cnonce=" + rp.Nonce;
}
}
return retval;
}
/// <summary>
/// Look at the current arguments and load the extension plugins needed to service
/// the request.
/// </summary>
/// <param name="rp">StateContainer object to store loaded plugins.</param>
internal static void AutoLoadExtensionPlugins(StateContainer rp)
{
if (rp == null) { throw new ArgumentNullException("rp"); }
Tracer.Write("Loading extension plugins");
Type[] types = GetRequiredExtensionPlugins(rp.RequestArguments);
foreach (Type t in types)
{
Tracer.Write("Loading plugin '" + t.ToString() + "'");
Activator.CreateInstance(t, rp);
}
}
