您可以使用 Reflection 创建对现有加密提供程序的扩展,以调用 MD4 的 CNG(.Net 可能应该这样做,或者使之变得更容易):
namespace System.Security.Cryptography {
[System.Runtime.InteropServices.ComVisible(true)]
public abstract class MD4 : HashAlgorithm {
static MD4() {
CryptoConfig.AddAlgorithm(typeof(MD4CryptoServiceProvider), "System.Security.Cryptography.MD4");
}
protected MD4() {
HashSizeValue = 128;
}
new static public MD4 Create() {
return Create("System.Security.Cryptography.MD4");
}
new static public MD4 Create(string algName) {
return (MD4)CryptoConfig.CreateFromName(algName);
}
}
[System.Runtime.InteropServices.ComVisible(true)]
public sealed class MD4CryptoServiceProvider : MD4 {
internal static class Utils {
internal static Type UtilsType = Type.GetType("System.Security.Cryptography.Utils");
public static T InvokeInternalMethodOfType<T>(object o, object pType, string methodName, params object[] args) {
var internalType = (pType is string internalTypeName) ? Type.GetType(internalTypeName) : (Type)pType;
var internalMethods = internalType.GetMethods(BindingFlags.NonPublic | BindingFlags.FlattenHierarchy | (o == null ? BindingFlags.Static : 0));
var internalMethod = internalMethods.Where(m => m.Name == methodName && m.GetParameters().Length == args.Length).Single();
return (T)internalMethod?.Invoke(o, args);
}
public static T GetInternalPropertyValueOfInternalType<T>(object o, object pType, string propertyName) {
var internalType = (pType is string internalTypeName) ? Type.GetType(internalTypeName) : (Type)pType;
var internalProperty = internalType.GetProperty(propertyName, BindingFlags.NonPublic | (o == null ? BindingFlags.Static : 0));
return (T)internalProperty.GetValue(o);
}
internal static SafeHandle CreateHash(int algid) {
return InvokeInternalMethodOfType<SafeHandle>(null, UtilsType, "CreateHash", GetInternalPropertyValueOfInternalType<object>(null, UtilsType, "StaticProvHandle"), algid);
}
internal static void HashData(SafeHandle h, byte[] data, int ibStart, int cbSize) {
InvokeInternalMethodOfType<object>(null, UtilsType, "HashData", h, data, ibStart, cbSize);
}
internal static byte[] EndHash(SafeHandle h) {
return InvokeInternalMethodOfType<byte[]>(null, UtilsType, "EndHash", h);
}
}
internal const int ALG_CLASS_HASH = (4 << 13);
internal const int ALG_TYPE_ANY = (0);
internal const int ALG_SID_MD4 = 2;
internal const int CALG_MD4 = (ALG_CLASS_HASH | ALG_TYPE_ANY | ALG_SID_MD4);
[System.Security.SecurityCritical]
private SafeHandle _safeHashHandle = null;
[System.Security.SecuritySafeCritical]
public MD4CryptoServiceProvider() {
if (CryptoConfig.AllowOnlyFipsAlgorithms)
throw new InvalidOperationException("Cryptography_NonCompliantFIPSAlgorithm");
Contract.EndContractBlock();
// cheat with Reflection
_safeHashHandle = Utils.CreateHash(CALG_MD4);
}
protected override void Dispose(bool disposing) {
if (_safeHashHandle != null && !_safeHashHandle.IsClosed)
_safeHashHandle.Dispose();
base.Dispose(disposing);
}
public override void Initialize() {
if (_safeHashHandle != null && !_safeHashHandle.IsClosed)
_safeHashHandle.Dispose();
_safeHashHandle = Utils.CreateHash(CALG_MD4);
}
protected override void HashCore(byte[] rgb, int ibStart, int cbSize) {
Utils.HashData(_safeHashHandle, rgb, ibStart, cbSize);
}
protected override byte[] HashFinal() {
return Utils.EndHash(_safeHashHandle);
}
}
}
完成此操作后,几个帮助器扩展将让您轻松使用它(我修改了它以创建一个单例,这样它就不必在每次使用它时都进行反射/创建的工作):
static class Ext {
public static HashAlgorithm MD4Singleton;
static Ext() {
MD4Singleton = System.Security.Cryptography.MD4.Create();
}
public static byte[] MD4(this string s) {
return MD4Singleton.ComputeHash(System.Text.Encoding.Unicode.GetBytes(s));
}
public static string AsHexString(this byte[] bytes) {
return String.Join("", bytes.Select(h => h.ToString("X2")));
}
}
现在您只需对一些示例数据调用扩展方法:
void Main() {
var input = "testing";
var hash = input.MD4();
var hashStr = hash.AsHexString();
Console.WriteLine(hashStr);
}