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我正在使用的代码（XE）：

// Encrypt a string and return the Base64 encoded result
function Encrypt(DataToEncrypt: ansistring):ansistring;
const Key: Ansistring = 'keykey';
  KeySize = 32; // 32 bytes = 256 bits
  BlockSize = 16; // 16 bytes = 128 bits
var
  Cipher : TDCP_rijndael;
  Data: ansistring;
  IV: array[0..15] of byte;      // the initialization vector
  i:Integer;
begin
  // Pad Key, IV and Data with zeros as appropriate
  FillChar(IV,Sizeof(IV),0);            // make the IV all zeros

  Data := PadWithZeros(DataToEncrypt,BlockSize);

  for i := 0 to (Length(IV) - 1) do   //just random values for the IV
    IV[i] := Random(256);

  Cipher := TDCP_rijndael.Create(nil);

  if Length(Key) <= 16 then
    Cipher.Init(Key[1],128,@IV[1])
  else if Length(Key) <= 24 then
    Cipher.Init(Key[1],192,@IV[1])
  else
    Cipher.Init(Key[1],256,@IV[1]);
  // Encrypt the data
  Cipher.EncryptCBC(Data[1],Data[1],Length(Data));
  // Free the cipher and clear sensitive information
  Cipher.Free;

  SetString(InitializationVector,PAnsiChar(@IV[1]),Length(IV));  //Save IV
  InitializationVector := Base64EncodeStr(InitializationVector);

  //Base64 encoded result
  Result := Base64EncodeStr(Data);
end;

function Decrypt(IV,Cryptogram:ansistring):ansistring;
const Key: Ansistring = 'keykey';
  KeySize = 32; // 32 bytes = 256 bits
  BlockSize = 16; // 16 bytes = 128 bits
var
  Cipher : TDCP_rijndael;
begin
  if IV='' then
    IV := InitializationVector;

  Cryptogram := Base64DecodeStr(cryptogram);
  // Create the cipher and initialise according to the key length
  cipher := tdcp_rijndael.Create(nil);
  if Length(Key) <= 16 then
    Cipher.Init(Key[1],128,@IV[1])
  else if Length(Key) <= 24 then
    Cipher.Init(Key[1],192,@IV[1])
  else
    Cipher.Init(Key[1],256,@IV[1]);
  // Decrypt the data
  Cipher.DecryptCBC(cryptogram[1],cryptogram[1],Length(cryptogram));
  // Free the cipher and clear sensitive information
  Cipher.Free;
  // Display the result
  Result := cryptogram;
end;

它工作得很好，除了当我尝试解密字符串时，我得到：

$C#$C'Ç'#$B'ÛW'#$1F'Ø‹™Ç'#$8D'Ž'#$8D'!'mydata

所以前几个字母会得到非常奇怪的字符。其余的解密就好了！在这里发现了类似的问题，但没有解决方案。提前致谢！

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1 回答 1

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对我来说突出的第一件事是您正在阅读/写作超过 IV 的结尾。您将其声明为 [0..15]，但在 Cipher.Init 和 SetString 中都可以访问从元素 1(!) 开始的所有内容。

于 2011-04-28T17:36:36.207 回答