public static async Task <bool> ValidateTokenAsync(IDictionary <string, object> env, OwinRequestValidationOptions options, string token)
{
if (env == null)
{
throw new ArgumentNullException("env");
}
if (options == null)
{
throw new ArgumentNullException("options");
}
if (String.IsNullOrWhiteSpace(token))
{
throw new ArgumentNullException("token");
}
var logger = Logging.GetLogger();
var ctx = new OwinContext(env);
var auth = await ctx.Authentication.AuthenticateAsync(HttpSigningConstants.AccessTokenParameterNames.AuthorizationHeaderScheme);
if (auth == null ||
auth.Identity == null ||
auth.Identity.IsAuthenticated == false)
{
logger.WriteError("Authentication failed for " + HttpSigningConstants.AccessTokenParameterNames.AuthorizationHeaderScheme + " scheme");
return(false);
}
var cnf = auth.Identity.FindFirst(HttpSigningConstants.Confirmation.ConfirmationProperty);
if (cnf == null)
{
logger.WriteError(HttpSigningConstants.Confirmation.ConfirmationProperty + " claim not present in authenticated user's claims");
return(false);
}
var jwk = CnfParser.Parse(cnf.Value);
if (jwk == null)
{
logger.WriteError("Failed to parse cnf claim");
return(false);
}
var key = jwk.ToPublicKey();
var signature = key.ToSignature();
var popValues = signature.Verify(token);
if (popValues == null)
{
logger.WriteError("Failed to verify signature on PoP token");
return(false);
}
if (popValues.TimeStamp == null || popValues.TimeStamp.Value <= 0)
{
logger.WriteError("No timestamp present in PoP object");
return(false);
}
var time = popValues.TimeStamp;
var now = DateTimeOffset.UtcNow.ToEpochTime();
var allowance = options.TimespanValidityWindow.TotalSeconds;
var low = now - allowance;
var high = now + allowance;
if (time < low || high < time)
{
logger.WriteError("Timestamp in PoP object is out of acceptable range");
return(false);
}
var owinRequestEncoding = await options.ReadEncodedParametersAsync(env, popValues);
var result = owinRequestEncoding.IsSame(popValues);
if (result == false)
{
logger.WriteError("Encoded values in PoP object do not match encoded values of current request");
}
else
{
logger.WriteInformation("PoP signature validation success");
}
return(result);
}
public HttpSignatureValidationOptions()
{
TokenProvider = DefaultPopTokenProvider.GetPopTokenAsync;
SignatureValidator = DefaultPopSignatureValidator.ValidateTokenAsync;
RequestValidationOptions = new OwinRequestValidationOptions();
}
