/// <summary>
/// Generates a signature using the specified signatureType
/// </summary>
/// <param name="url">The full url that needs to be signed including its non OAuth url parameters</param>
/// <param name="consumerKey">The consumer key</param>
/// <param name="consumerSecret">The consumer seceret</param>
/// <param name="token">The token, if available. If not available pass null or an empty string</param>
/// <param name="tokenSecret">The token secret, if available. If not available pass null or an empty string</param>
/// <param name="httpMethod">The http method used. Must be a valid HTTP method verb (POST,GET,PUT, etc)</param>
/// <param name="signatureType">The type of signature to use</param>
/// <returns>A base64 string of the hash value</returns>
public string GenerateSignature(Uri url, string consumerKey, string consumerSecret, string token, string tokenSecret, string httpMethod, string timeStamp, string nonce, SignatureTypes signatureType, out string normalizedUrl, out string normalizedRequestParameters)
{
normalizedUrl = null;
normalizedRequestParameters = null;
switch (signatureType)
{
case SignatureTypes.PLAINTEXT:
return(Uri.EscapeDataString(string.Format("{0}&{1}", consumerSecret, tokenSecret)));
case SignatureTypes.HMACSHA1:
string signatureBase = GenerateSignatureBase(url, consumerKey, token, tokenSecret, httpMethod, timeStamp, nonce, HMACSHA1SignatureType, out normalizedUrl, out normalizedRequestParameters);
HMACSHA1 hmacsha1 = new HMACSHA1();
hmacsha1.Key = YahooExtensions.StringToAscii(string.Format("{0}&{1}", UrlEncode(consumerSecret), string.IsNullOrEmpty(tokenSecret) ? "" : UrlEncode(tokenSecret)));
return(GenerateSignatureUsingHash(signatureBase, hmacsha1));
case SignatureTypes.RSASHA1:
throw new NotImplementedException();
default:
throw new ArgumentException("Unknown signature type", "signatureType");
}
}
/// <summary>
/// Helper function to compute a hash value
/// </summary>
/// <param name="hashAlgorithm">The hashing algoirhtm used. If that algorithm needs some initialization, like HMAC and its derivatives, they should be initialized prior to passing it to this function</param>
/// <param name="data">The data to hash</param>
/// <returns>a Base64 string of the hash value</returns>
private string ComputeHash(HashAlgorithm hashAlgorithm, string data)
{
if (hashAlgorithm == null)
{
throw new ArgumentNullException("hashAlgorithm");
}
if (string.IsNullOrEmpty(data))
{
throw new ArgumentNullException("data");
}
byte[] dataBuffer = YahooExtensions.StringToAscii(data);
byte[] hashBytes = hashAlgorithm.ComputeHash(dataBuffer);
return(Convert.ToBase64String(hashBytes));
}
