/// <summary>
/// 计算哈希值
/// </summary>
/// <param name="stream">要计算哈希值的 Stream</param>
/// <param name="algName">算法:sha1,md5</param>
/// <returns>哈希值字节数组</returns>
public static byte[] HashData(Stream stream, string algName)
{
HashAlgorithm algorithm;
if (algName == null)
{
throw new ArgumentNullException("algName 不能为 null");
}
if (string.Compare(algName, "sha256", true) == 0)
{
algorithm = SHA256.Create();
}
else if (string.Compare(algName, "sm3", true) == 0)
{
algorithm = SM3.Create();
}
else
{
if (string.Compare(algName, "md5", true) != 0)
{
throw new Exception("algName 只能使用 sha256 或 md5");
}
algorithm = MD5.Create();
}
return(algorithm.ComputeHash(stream));
}
/// <summary>
/// 拷贝构造函数
/// </summary>
/// <param name="Source">要复制的对象实例</param>
public SM3(SM3 Source)
{
BytesCount = Source.BytesCount;
WOff = Source.WOff;
if (WOff > 0)
{
Array.Copy(Source.W, W, WOff);
}
MOff = Source.MOff;
if (MOff > 0)
{
Array.Copy(Source.M, M, MOff);
}
// 拷贝状态向量
Array.Copy(Source.V, V, V.Length);
}
