delphi加密C#解密(AES-256)

因为公司内部业务需要,用delphi加密的内容(流和字符串)要用C#解密,因为不懂delphi,我这里只是问同事要了代码,贴上

delphi加密:

共两个文件(AES.pas 和 ElAES.pas),ElAES这个文件应该是类似C#的第三方库,代码我就不贴了

AES.pas :

(**************************************************************)
(*                                                            *)
(*    AES Delphi 加密算法                                                        *)
(*                                                            *)
(*                                                            *)
(*                                                            *)
(**************************************************************)

unit AES;                  

interface

//{$DEFINE VER210}
//{$IFDEF VER210}
//  {$WARN IMPLICIT_STRING_CAST OFF} //关闭警告
//  {$WARN IMPLICIT_STRING_CAST_LOSS OFF}
//{$ENDIF}
uses
  SysUtils, Classes, Math, ElAES;

const
  SDestStreamNotCreated = 'Dest stream not created.';
  SEncryptStreamError = 'Encrypt stream error.';
  SDecryptStreamError = 'Decrypt stream error.';

type
  TKeyBit = (kb128, kb192, kb256);

function StrToHex(Const str: AnsiString): AnsiString;
function HexToStr(const Value: AnsiString): AnsiString;

function EncryptString(Value: AnsiString; Key: AnsiString;
  KeyBit: TKeyBit = kb128): AnsiString;
function DecryptString(Value: AnsiString; Key: AnsiString;
  KeyBit: TKeyBit = kb128): AnsiString;

function EncryptStream(Src: TStream; Key: AnsiString;
  var Dest: TStream; KeyBit: TKeyBit = kb128): Boolean;
function DecryptStream(Src: TStream; Key: AnsiString;
  var Dest: TStream; KeyBit: TKeyBit = kb128): Boolean;

procedure EncryptFile(SourceFile, DestFile: String;
  Key: AnsiString; KeyBit: TKeyBit = kb128);
procedure DecryptFile(SourceFile, DestFile: String;
  Key: AnsiString; KeyBit: TKeyBit = kb128);

implementation

function StrToHex(Const str: Ansistring): Ansistring;
asm
    push ebx
    push esi
    push edi
    test eax,eax
    jz   @@Exit
    mov  esi,edx       //保存edx值,用来产生新字符串的地址
    mov  edi,eax       //保存原字符串
    mov  edx,[eax-4]  //获得字符串长度
    test edx,edx      //检查长度
    je   @@Exit      {Length(S) = 0}
    mov  ecx,edx       //保存长度
    Push ecx
    shl  edx,1
    mov  eax,esi
    {$IFDEF VER210}
    movzx ecx, word ptr [edi-12] {需要设置CodePage}
    {$ENDIF}
    call System.@LStrSetLength //设置新串长度
    mov  eax,esi       //新字符串地址
    Call UniqueString  //产生一个唯一的新字符串,串位置在eax中
    Pop   ecx
  @@SetHex:
    xor  edx,edx       //清空edx
    mov  dl, [edi]     //Str字符串字符
    mov  ebx,edx       //保存当前的字符
    shr  edx,4         //右移4字节,得到高8位
    mov  dl,byte ptr[edx+@@HexChar] //转换成字符
    mov  [eax],dl      //将字符串输入到新建串中存放
    and  ebx,$0F       //获得低8位
    mov  dl,byte ptr[ebx+@@HexChar] //转换成字符
    inc  eax             //移动一个字节,存放低位
    mov  [eax],dl
    inc  edi
    inc  eax
    loop @@SetHex
  @@Exit:
    pop  edi
    pop  esi
    pop  ebx
    ret
  @@HexChar: db '0123456789ABCDEF'
end;

function HexToStr(const Value: AnsiString): AnsiString;
asm
  push ebx
  push edi
  push esi
  test eax,eax //为空串
  jz   @@Exit
  mov  edi,eax
  mov  esi,edx
  mov  edx,[eax-4]
  test edx,edx
  je   @@Exit
  mov  ecx,edx
  push ecx
  shr  edx,1
  mov  eax,esi //开始构造字符串
  {$IFDEF VER210}
  movzx ecx, word ptr [edi-12] {需要设置CodePage}
  {$ENDIF}
  call System.@LStrSetLength //设置新串长度
  mov  eax,esi       //新字符串地址
  Call UniqueString  //产生一个唯一的新字符串,串位置在eax中
  Pop   ecx
  xor  ebx,ebx
  xor  esi,esi
@@CharFromHex:
  xor  edx,edx
  mov  dl, [edi]     //Str字符串字符
  cmp  dl, '0'  //查看是否在0到f之间的字符
  JB   @@Exit   //小于0,退出
  cmp  dl,'9'   //小于=9
  ja  @@DoChar//CompOkNum
  sub  dl,'0'
  jmp  @@DoConvert
@@DoChar:
  //先转成大写字符
  and  dl,$DF
  cmp  dl,'F'
  ja   @@Exit  //大于F退出
  add  dl,10
  sub  dl,'A'
@@DoConvert: //转化
  inc  ebx
  cmp  ebx,2
  je   @@Num1
  xor  esi,esi
  shl  edx,4
  mov  esi,edx
  jmp  @@Num2
@@Num1:
  add  esi,edx
  mov  edx,esi
  mov  [eax],dl
  xor  ebx,ebx
  inc  eax
@@Num2:
  dec  ecx
  inc  edi
  test ecx,ecx
  jnz  @@CharFromHex
@@Exit:
  pop  esi
  pop  edi
  pop  ebx
end;

{  --  字符串加密函数 默认按照 128 位密匙加密 --  }
function EncryptString(Value: AnsiString; Key: AnsiString;
  KeyBit: TKeyBit = kb128): AnsiString;
var
  {$IFDEF VER210}
  SS,DS: TMemoryStream;
  {$ELSE}
  SS, DS: TStringStream;
  {$ENDIF}
  Size: Int64;
  AESKey128: TAESKey128;
  AESKey192: TAESKey192;
  AESKey256: TAESKey256;
  st: AnsiString;
begin
  Result := '';
  {$IFDEF VER210}
    ss := TMemoryStream.Create;
    SS.WriteBuffer(PAnsiChar(Value)^,Length(Value));
    DS := TMemoryStream.Create;
  {$ELSE}
    SS := TStringStream.Create(Value);
    DS := TStringStream.Create('');
  {$ENDIF}
  try
    Size := SS.Size;
//    DS.WriteBuffer(Size, SizeOf(Size));
    {  --  128 位密匙最大长度为 16 个字符 --  }
    if KeyBit = kb128 then
    begin
      FillChar(AESKey128, SizeOf(AESKey128), 0 );
      Move(PAnsiChar(Key)^, AESKey128, Min(SizeOf(AESKey128), Length(Key)));
      EncryptAESStreamECB(SS, 0, AESKey128, DS);
    end;
    {  --  192 位密匙最大长度为 24 个字符 --  }
    if KeyBit = kb192 then
    begin
      FillChar(AESKey192, SizeOf(AESKey192), 0 );
      Move(PAnsiChar(Key)^, AESKey192, Min(SizeOf(AESKey192), Length(Key)));
      EncryptAESStreamECB(SS, 0, AESKey192, DS);
    end;
    {  --  256 位密匙最大长度为 32 个字符 --  }
    if KeyBit = kb256 then
    begin
      FillChar(AESKey256, SizeOf(AESKey256), 0 );
      Move(PAnsiChar(Key)^, AESKey256, Min(SizeOf(AESKey256), Length(Key)));
      EncryptAESStreamECB(SS, 0, AESKey256, DS);
    end;
    {$IFDEF VER210}
      SetLength(st,Ds.Size);
      DS.Position := 0;
      DS.ReadBuffer(PAnsiChar(st)^,DS.Size);
      Result := StrToHex(st);
    {$ELSE}
      Result := StrToHex(DS.DataString);
    {$ENDIF}
  finally
    SS.Free;
    DS.Free;
  end;
end;

{  --  字符串解密函数 默认按照 128 位密匙解密 --  }
function DecryptString(Value: AnsiString; Key: AnsiString;
  KeyBit: TKeyBit = kb128): AnsiString;
var
  SS, DS: TStringStream;
  Size: Int64;
  AESKey128: TAESKey128;
  AESKey192: TAESKey192;
  AESKey256: TAESKey256;
begin
  Result := '';
  SS := TStringStream.Create(HexToStr(Value));
  DS := TStringStream.Create('');
  try
    Size := SS.Size;
//    SS.ReadBuffer(Size, SizeOf(Size));
    {  --  128 位密匙最大长度为 16 个字符 --  }
    if KeyBit = kb128 then
    begin
      FillChar(AESKey128, SizeOf(AESKey128), 0 );
      Move(PAnsiChar(Key)^, AESKey128, Min(SizeOf(AESKey128), Length(Key)));
      DecryptAESStreamECB(SS, SS.Size - SS.Position, AESKey128, DS);
    end;
    {  --  192 位密匙最大长度为 24 个字符 --  }
    if KeyBit = kb192 then
    begin
      FillChar(AESKey192, SizeOf(AESKey192), 0 );
      Move(PAnsiChar(Key)^, AESKey192, Min(SizeOf(AESKey192), Length(Key)));
      DecryptAESStreamECB(SS, SS.Size - SS.Position, AESKey192, DS);
    end;
    {  --  256 位密匙最大长度为 32 个字符 --  }
    if KeyBit = kb256 then
    begin
      FillChar(AESKey256, SizeOf(AESKey256), 0 );
      Move(PAnsiChar(Key)^, AESKey256, Min(SizeOf(AESKey256), Length(Key)));
      DecryptAESStreamECB(SS, SS.Size - SS.Position, AESKey256, DS);
    end;
    Result := DS.DataString;
  finally
    SS.Free;
    DS.Free;
  end;
end;

{ 流加密函数, default keybit: 128bit }
function EncryptStream(Src: TStream; Key: AnsiString;
  var Dest: TStream; KeyBit: TKeyBit = kb128): Boolean;
var
  Count: Int64;
  AESKey128: TAESKey128;
  AESKey192: TAESKey192;
  AESKey256: TAESKey256;
begin
  if Dest = nil then
  begin
    raise Exception.Create(SDestStreamNotCreated);
    Result:= False;
    Exit;
  end;

  try
    Src.Position:= 0;
//    Count:= Src.Size;
//    Dest.Write(Count, SizeOf(Count));
    {  --  128 位密匙最大长度为 16 个字符 --  }
    if KeyBit = kb128 then
    begin
      FillChar(AESKey128, SizeOf(AESKey128), 0 );
      Move(PAnsiChar(Key)^, AESKey128, Min(SizeOf(AESKey128), Length(Key)));
      EncryptAESStreamECB(Src, 0, AESKey128, Dest);
    end;
    {  --  192 位密匙最大长度为 24 个字符 --  }
    if KeyBit = kb192 then
    begin
      FillChar(AESKey192, SizeOf(AESKey192), 0 );
      Move(PAnsiChar(Key)^, AESKey192, Min(SizeOf(AESKey192), Length(Key)));
      EncryptAESStreamECB(Src, 0, AESKey192, Dest);
    end;
    {  --  256 位密匙最大长度为 32 个字符 --  }
    if KeyBit = kb256 then
    begin
      FillChar(AESKey256, SizeOf(AESKey256), 0 );
      Move(PAnsiChar(Key)^, AESKey256, Min(SizeOf(AESKey256), Length(Key)));
      EncryptAESStreamECB(Src, 0, AESKey256, Dest);
    end;

    Result := True;
  except
    raise Exception.Create(SEncryptStreamError);
    Result:= False;
  end;
end;

{ 流解密函数, default keybit: 128bit }
function DecryptStream(Src: TStream; Key: AnsiString;
  var Dest: TStream; KeyBit: TKeyBit = kb128): Boolean;
var
  Count, OutPos: Int64;
  AESKey128: TAESKey128;
  AESKey192: TAESKey192;
  AESKey256: TAESKey256;
begin
  if Dest = nil then
  begin
    raise Exception.Create(SDestStreamNotCreated);
    Result:= False;
    Exit;
  end;

  try
    Src.Position:= 0;
    OutPos:= Dest.Position;
//    Src.ReadBuffer(Count, SizeOf(Count));
     Count := Src.Size;
    {  --  128 位密匙最大长度为 16 个字符 --  }
    if KeyBit = kb128 then
    begin
      FillChar(AESKey128, SizeOf(AESKey128), 0 );
      Move(PAnsiChar(Key)^, AESKey128, Min(SizeOf(AESKey128), Length(Key)));
      DecryptAESStreamECB(Src, Src.Size - Src.Position,
        AESKey128, Dest);
    end;
    {  --  192 位密匙最大长度为 24 个字符 --  }
    if KeyBit = kb192 then
    begin
      FillChar(AESKey192, SizeOf(AESKey192), 0 );
      Move(PAnsiChar(Key)^, AESKey192, Min(SizeOf(AESKey192), Length(Key)));
      DecryptAESStreamECB(Src, Src.Size - Src.Position,
        AESKey192, Dest);
    end;
    {  --  256 位密匙最大长度为 32 个字符 --  }
    if KeyBit = kb256 then
    begin
      FillChar(AESKey256, SizeOf(AESKey256), 0 );
      Move(PAnsiChar(Key)^, AESKey256, Min(SizeOf(AESKey256), Length(Key)));
      DecryptAESStreamECB(Src, Src.Size - Src.Position,
        AESKey256, Dest);
    end;
//    Dest.Size := OutPos + Count;
    Dest.Position := OutPos;

    Result := True;
  except
    raise Exception.Create(SDecryptStreamError);
    Result:= False;
  end;
end;

{  --  文件加密函数 默认按照 128 位密匙解密 --  }
procedure EncryptFile(SourceFile, DestFile: String;
  Key: AnsiString; KeyBit: TKeyBit = kb128);
var
  SFS, DFS: TFileStream;
  Size: Int64;
  AESKey128: TAESKey128;
  AESKey192: TAESKey192;
  AESKey256: TAESKey256;
begin
  SFS := TFileStream.Create(SourceFile, fmOpenRead);
  try
    DFS := TFileStream.Create(DestFile, fmCreate);
    try
//      Size := SFS.Size;
//      DFS.WriteBuffer(Size, SizeOf(Size));
      {  --  128 位密匙最大长度为 16 个字符 --  }
      if KeyBit = kb128 then
      begin
        FillChar(AESKey128, SizeOf(AESKey128), 0 );
        Move(PAnsiChar(Key)^, AESKey128, Min(SizeOf(AESKey128), Length(Key)));
        EncryptAESStreamECB(SFS, 0, AESKey128, DFS);
      end;
      {  --  192 位密匙最大长度为 24 个字符 --  }
      if KeyBit = kb192 then
      begin
        FillChar(AESKey192, SizeOf(AESKey192), 0 );
        Move(PAnsiChar(Key)^, AESKey192, Min(SizeOf(AESKey192), Length(Key)));
        EncryptAESStreamECB(SFS, 0, AESKey192, DFS);
      end;
      {  --  256 位密匙最大长度为 32 个字符 --  }
      if KeyBit = kb256 then
      begin
        FillChar(AESKey256, SizeOf(AESKey256), 0 );
        Move(PAnsiChar(Key)^, AESKey256, Min(SizeOf(AESKey256), Length(Key)));
        EncryptAESStreamECB(SFS, 0, AESKey256, DFS);
      end;
    finally
      DFS.Free;
    end;
  finally
    SFS.Free;
  end;
end;

{  --  文件解密函数 默认按照 128 位密匙解密 --  }
procedure DecryptFile(SourceFile, DestFile: String;
  Key: AnsiString; KeyBit: TKeyBit = kb128);
var
  SFS, DFS: TFileStream;
  Size: Int64;
  AESKey128: TAESKey128;
  AESKey192: TAESKey192;
  AESKey256: TAESKey256;
begin
  SFS := TFileStream.Create(SourceFile, fmOpenRead);
  try
    Size := SFS.Size;
//    SFS.ReadBuffer(Size, SizeOf(Size));
    DFS := TFileStream.Create(DestFile, fmCreate);
    try
      {  --  128 位密匙最大长度为 16 个字符 --  }
      if KeyBit = kb128 then
      begin
        FillChar(AESKey128, SizeOf(AESKey128), 0 );
        Move(PAnsiChar(Key)^, AESKey128, Min(SizeOf(AESKey128), Length(Key)));
        DecryptAESStreamECB(SFS, SFS.Size - SFS.Position, AESKey128, DFS);
      end;
      {  --  192 位密匙最大长度为 24 个字符 --  }
      if KeyBit = kb192 then
      begin
        FillChar(AESKey192, SizeOf(AESKey192), 0 );
        Move(PAnsiChar(Key)^, AESKey192, Min(SizeOf(AESKey192), Length(Key)));
        DecryptAESStreamECB(SFS, SFS.Size - SFS.Position, AESKey192, DFS);
      end;
      {  --  256 位密匙最大长度为 32 个字符 --  }
      if KeyBit = kb256 then
      begin
        FillChar(AESKey256, SizeOf(AESKey256), 0 );
        Move(PAnsiChar(Key)^, AESKey256, Min(SizeOf(AESKey256), Length(Key)));
        DecryptAESStreamECB(SFS, SFS.Size - SFS.Position, AESKey256, DFS);
      end;
      DFS.Size := Size;
    finally
      DFS.Free;
    end;
  finally
    SFS.Free;
  end;
end;
end.

 

C#解密:

/// <summary>
/// 解密delphi加密字符串和流
/// </summary>
public class AesDelphi
{
    public static byte[] HexStringToBytes(string hex)
    {
        if (hex.Length % 2 != 0)
            throw new ArgumentException("Hex string must have an even length");

        byte[] bytes = new byte[hex.Length / 2];
        for (int i = 0; i < hex.Length; i += 2)
        {
            bytes[i / 2] = Convert.ToByte(hex.Substring(i, 2), 16);
        }

        return bytes;
    }
    /// <summary>
    /// 解密字符串
    /// </summary>
    /// <param name="encryptedText"></param>
    /// <param name="key"></param>
    /// <returns></returns>
    public static string DecryptString(string encryptedText, string key)
    {
        /*
         ECB模式,不会使用到IV,只有CBC模式才会使用IV设置成null就行,设置成空数组也行
         Aes的iv不能设置null,可以设置到aes.CreateDecryptor(aes.Key, null))

         aesAlg.KeySize = 256;千万不要设置,如果想设置要放到设置Key的前面,设置Key的时候会重置KeySize
         只要保证key的大小即可,需要判定一下
         if (Key == null || Key.Length != 32)
           throw new ArgumentNullException(nameof(Key));

         aesAlg.BlockSize = 128; 默认的不需要设置,和Delphi一致              
        */

        byte[] array = HexStringToBytes(encryptedText);  // Convert.FromBase64String(encryptedText);

        using (Aes aes = Aes.Create())
        {
            aes.Key = Encoding.UTF8.GetBytes(key);
            aes.Mode = CipherMode.ECB; // 确保和Delphi端的模式相匹配
            aes.Padding = PaddingMode.PKCS7; // 确保和Delphi端的填充模式相匹配

            using (ICryptoTransform decryptor = aes.CreateDecryptor(aes.Key, null))
            {
                using (MemoryStream ms = new MemoryStream())
                {
                    using (CryptoStream cs = new CryptoStream(ms, decryptor, CryptoStreamMode.Write))
                    {
                        cs.Write(array, 0, array.Length);
                        cs.FlushFinalBlock();
                        byte[] decryptedBytes = ms.ToArray();
                        return Encoding.UTF8.GetString(decryptedBytes).TrimEnd('\0');
                    }
                }
            }
        }
    }
    /// <summary>
    /// 解密文件流
    /// </summary>
    /// <param name="encryptedData"></param>
    /// <param name="key"></param>
    /// <returns></returns>
    public static byte[] DecryptByte(byte[] encryptedData, string key)
    {
        /*
         ECB模式,不会使用到IV,只有CBC模式才会使用IV设置成null就行,设置成空数组也行
         Aes的iv不能设置null,可以设置到aes.CreateDecryptor(aes.Key, null))

         aesAlg.KeySize = 256;千万不要设置,如果想设置要放到设置Key的前面,设置Key的时候会重置KeySize
         只要保证key的大小即可,需要判定一下
         if (Key == null || Key.Length != 32)
           throw new ArgumentNullException(nameof(Key));

         aesAlg.BlockSize = 128; 默认的不需要设置,和Delphi一致              
        */
        //string encryptedText = Encoding.UTF8.GetString(encryptedData);
        //byte[] array = HexStringToBytes(encryptedText);  // Convert.FromBase64String(encryptedText);

        using (Aes aes = Aes.Create())
        {
            aes.Key = Encoding.UTF8.GetBytes(key);
            aes.Mode = CipherMode.ECB; // 确保和Delphi端的模式相匹配
            aes.Padding = PaddingMode.PKCS7; // 确保和Delphi端的填充模式相匹配

            byte[] decryptBytes = new byte[encryptedData.Length];

            using (ICryptoTransform decryptor = aes.CreateDecryptor(aes.Key, null))
            {
                using (MemoryStream ms = new MemoryStream(encryptedData))
                {
                    using (CryptoStream cs = new CryptoStream(ms, decryptor, CryptoStreamMode.Read))
                    {
                        cs.Read(decryptBytes, 0, decryptBytes.Length);

                        return decryptBytes;
                    }
                }
            }
        }
    }
}

 

posted @ 2024-08-20 09:50  卡萨丁·周  阅读(101)  评论(0编辑  收藏  举报