2

我正在尝试编写一个函数，该函数在 Delphi (RAD Studio 10.2) 中返回与 PHP 中的以下代码相同的结果：

<?php
  $method = 'AES-256-CTR';
  $data = 'Hello, world!';
  $key = 'bRuD5WYw5wd0rdHR9yLlM6wt2vteuini';
  $vector = 'bf49ea9d61104d8c'; 
  $crypt = openssl_encrypt($data, $method, $key, 0, $vector);
  echo $crypt;
?>

我在 Pascal 中提出了这个函数（使用 David Barton 编写的 DCPcrypt v2.1 库）：

procedure TMainForm.Encrypt1ButtonClick(Sender: TObject);
var
  Cipher: TDCP_rijndael;
  Key, Vector: RawByteString;
  Data, Crypt: RawByteString;
begin
  Data := 'Hello, world!';                    
  SetLength(Crypt, Length(Data));
  Key := 'bRuD5WYw5wd0rdHR9yLlM6wt2vteuini';  
  Vector := 'bf49ea9d61104d8c';               
  Cipher := TDCP_rijndael.Create(nil);
  try
    Cipher.Init(Key[1], 256, @Vector[1]);
    Cipher.EncryptCTR(Data[1], Crypt[1], Length(Data));
  finally
    Cipher.Free;
  end;
  EncryptEdit.Text := DCPBase64.Base64EncodeStr(Crypt);
end;

这确实有效（在 Windows 中）。PHP 和 Pascal 都返回：pEP16OOxov9QDfraIg==

但是，如果我为 Android 编译相同的代码并在我的平板电脑上运行它，我会得到一个非常不同的结果。这是为什么？

我确实阅读了有关为 fmx 转换代码的文档，特别是处理字符串处理的内容，但我仍然不明白为什么。即使 RawByteString 是基于 0 而不是基于 1，我仍然会有所不同（尝试使用 [0] 而不是 [1]）。RawByteString 没有附加代码页，对吗？所以问题不能由一些字符串转换引起（我认为）。那么这里发生了什么？

4

2 回答 2

3

在这工作了3天后，我终于让它工作了。关键是完全消除字符串的使用，只使用 DCPCrypt 中基于 TBytes 的例程。下面的代码是一个测试程序，用于测试 DCPCrypt 支持的所有不同的链接模式。我还添加了一个函数来实现我在这里找到的四种填充模式（用于 CBC 和 ECB）： https://en.wikipedia.org/wiki/Padding_(cryptography) 以及零填充和随机填充。我选择不使用 DCPCrypt 自己的 Base64 函数，因为它们与 FMX 不兼容。相反，我使用 System.NetEncoding 单元中的对应项。拜托，我认为自己只是一个普通的程序员，所以我希望你们中真正的德尔福奇才能够找到很多批评。但没关系。如果给出良好的反馈，我会修改代码。就像现在一样，代码工作并产生与 PHP 的 openssl 函数兼容的结果（使用 CTR 模式测试）。我只是在这里发布这个，希望它对寻找与我相同的解决方案的人有用。

    unit MainUnit;

    interface

    uses
      System.SysUtils, System.Types, System.UITypes, System.Classes, System.Variants, System.NetEncoding,
      FMX.Types, FMX.Controls, FMX.Forms, FMX.Graphics, FMX.Dialogs, FMX.StdCtrls, FMX.Layouts,
      FMX.ScrollBox, FMX.Memo, FMX.Edit, FMX.Controls.Presentation,
      DCPcrypt2, DCPsha256, DCPblockciphers, DCPrijndael;

    type
      TChainingMode = (cmCBC, cmCFB8bit, cmCFBblock, cmOFB, cmCTR, cmECB);
      TPaddingMode = (pmZeroPadding, pmANSIX923, pmISO10126, pmISO7816, pmPKCS7, pmRandomPadding);

    type
      TMainForm = class(TForm)
        ScrollBox: TScrollBox;
        KeySizeLabel: TLabel;
        ChainingLabel: TLabel;
        EncodingLabel: TLabel;
        PaddingLabel: TLabel;
        KeyLabel: TLabel;
        InitVectorLabel: TLabel;
        DataLabel: TLabel;
        DecryptedLabel: TLabel;
        CipherLabel: TLabel;
        EncryptedLabel: TLabel;
        rbRijndael: TRadioButton;
        rb128bit: TRadioButton;
        rb256bit: TRadioButton;
        rbANSI: TRadioButton;
        rbUTF8: TRadioButton;
        rbUnicode: TRadioButton;
        rbCBC: TRadioButton;
        rbOFB: TRadioButton;
        rbCTR: TRadioButton;
        rbECB: TRadioButton;
        rbCFB8bit: TRadioButton;
        rbCFBblock: TRadioButton;
        rbZeroPadding: TRadioButton;
        rbANSIX923: TRadioButton;
        rbISO10126: TRadioButton;
        rbISO7816: TRadioButton;
        rbPKCS7: TRadioButton;
        rbRandomPadding: TRadioButton;
        KeyEdit: TEdit;
        InitVectorEdit: TEdit;
        DataMemo: TMemo;
        EncryptedMemo: TMemo;
        DecryptedMemo: TMemo;
        EncryptButton: TButton;
        DecryptButton: TButton;
        procedure FormCreate(Sender: TObject);
        procedure EncryptButtonClick(Sender: TObject);
        procedure DecryptButtonClick(Sender: TObject);
      public
        procedure GetOptions(var Key: TBytes; var KeySize: integer; var InitVector: TBytes;
                  var Encoding: TEncoding; var ChainingMode: TChainingMode; var PaddingMode: TPaddingMode);
      end;

    var
      MainForm: TMainForm;

    implementation

    {$R *.fmx}
    {$R *.LgXhdpiPh.fmx ANDROID}

    function BytesToHex(B: TBytes): string;
    var
      I: integer;
    begin
      Result := '';
      for I := Low(B) to High(B) do Result := Result + IntToHex(B[I]) + ' ';
    end;

    procedure BytePadding(var Data: TBytes; BlockSize: integer; PaddingMode: TPaddingMode);
    // Supports: ANSI X.923, ISO 10126, ISO 7816, PKCS7, zero padding and random padding
    var
      I, DataBlocks, DataLength, PaddingStart, PaddingCount: integer;
    begin
      BlockSize := BlockSize div 8; // convert bits to bytes
      // Zero and Random padding do not use end-markers, so if Length(Data) is a multiple of BlockSize, no padding is needed
      if PaddingMode in [pmZeroPadding, pmRandomPadding] then
        if Length(Data) mod BlockSize = 0 then Exit;
      DataBlocks := (Length(Data) div BlockSize) + 1;
      DataLength := DataBlocks * BlockSize;
      PaddingCount := DataLength - Length(Data);
      // ANSIX923, ISO10126 and PKCS7 store the padding length in a 1 byte end-marker, so any padding length > $FF is not supported
      if PaddingMode in [pmANSIX923, pmISO10126, pmPKCS7] then
        if PaddingCount > $FF then Exit;
      PaddingStart := Length(Data);
      SetLength(Data, DataLength);
      case PaddingMode of
        pmZeroPadding, pmANSIX923, pmISO7816: // fill with $00 bytes
          FillChar(Data[PaddingStart], PaddingCount, 0);
        pmPKCS7: // fill with PaddingCount bytes
          FillChar(Data[PaddingStart], PaddingCount, PaddingCount);
        pmRandomPadding, pmISO10126: // fill with random bytes
          for I := PaddingStart to DataLength-1 do Data[I] := Random($FF);
      end;
      case PaddingMode of
        pmANSIX923, pmISO10126:
          Data[DataLength-1] := PaddingCount; // set end-marker with number of bytes added
        pmISO7816:
          Data[PaddingStart] := $80; // set fixed end-markder $80
      end;
    end;

    procedure EncryptAES(const Data: TBytes; var Crypt: TBytes; const Key: TBytes; KeySize: integer;
        const InitVector: TBytes; ChainingMode: TChainingMode; PaddingMode: TPaddingMode); overload;
    var
      Cipher: TDCP_rijndael;
    begin
      Cipher := TDCP_rijndael.Create(nil);
      try
        Cipher.Init(Key[0], KeySize, @InitVector[0]);
        // Copy Data => Crypt
        Crypt := Copy(Data, 0, Length(Data));
        // Padd Crypt to required length (for Block based algorithms)
        if ChainingMode in [cmCBC, cmECB] then
          BytePadding(Crypt, Cipher.BlockSize, PaddingMode);
        // Encrypt Crypt using the algorithm specified in ChainingMode
        case ChainingMode of
          cmCBC: Cipher.EncryptCBC(Crypt[0], Crypt[0], Length(Crypt));
          cmCFB8bit: Cipher.EncryptCFB8bit(Crypt[0], Crypt[0], Length(Crypt));
          cmCFBblock: Cipher.EncryptCFBblock(Crypt[0], Crypt[0], Length(Crypt));
          cmOFB: Cipher.EncryptOFB(Crypt[0], Crypt[0], Length(Crypt));
          cmCTR: Cipher.EncryptCTR(Crypt[0], Crypt[0], Length(Crypt));
          cmECB: Cipher.EncryptECB(Crypt[0], Crypt[0]);
        end;

      finally
        Cipher.Free;
      end;
    end;

    procedure DecryptAES(const Crypt: TBytes; var Data: TBytes; const Key: TBytes; KeySize: integer;
        const InitVector: TBytes; ChainingMode: TChainingMode; PaddingMode: TPaddingMode); overload;
    var
      Cipher: TDCP_rijndael;
      I: integer;
    begin
      Cipher := TDCP_rijndael.Create(nil);
      try
        Cipher.Init(Key[0], KeySize, @InitVector[0]);
        // Copy Crypt => Data
        Data := Copy(Crypt, 0, Length(Crypt));
        // Decrypt Data using the algorithm specified in ChainingMode
        case ChainingMode of
          cmCBC: Cipher.DecryptCBC(Data[0], Data[0], Length(Data));
          cmCFB8bit: Cipher.DecryptCFB8bit(Data[0], Data[0], Length(Data));
          cmCFBblock: Cipher.DecryptCFBblock(Data[0], Data[0], Length(Data));
          cmOFB: Cipher.DecryptOFB(Data[0], Data[0], Length(Data));
          cmCTR: Cipher.DecryptCTR(Data[0], Data[0], Length(Data));
          cmECB: Cipher.DecryptECB(Data[0], Data[0]);
        end;
        // Correct the length of Data, based on the used PaddingMode (only for Block based algorithms)
        if ChainingMode in [cmCBC, cmECB] then
          case PaddingMode of
            pmANSIX923, pmISO10126, pmPKCS7: // these modes store the original Padding count in the last byte
              SetLength(Data, Length(Data) - Data[Length(Data)-1]);
            pmISO7816: // this mode uses a fixed end-marker. Find it and correct length accordingly.
              for I := Length(Data)-1 downto 0 do
                if Data[I] = $80 then
                begin
                  SetLength(Data, I);
                  Break;
                end;
          end;

      finally
        Cipher.Free;
      end;
    end;

    procedure TMainForm.FormCreate(Sender: TObject);
    begin
      EncryptedMemo.Lines.Clear;
      DecryptedMemo.Lines.Clear;
    end;

    procedure TMainForm.GetOptions(var Key: TBytes; var KeySize: integer; var InitVector: TBytes;
              var Encoding: TEncoding; var ChainingMode: TChainingMode; var PaddingMode: TPaddingMode);
    begin
      KeySize := 256;
      Encoding := TEncoding.ANSI;
      ChainingMode := cmCBC;
      PaddingMode := pmPKCS7;

      if rb128bit.IsChecked then KeySize := 128;
      if rb256bit.IsChecked then KeySize := 256;

      if rbCBC.IsChecked then ChainingMode := cmCBC;
      if rbCFB8bit.IsChecked then ChainingMode := cmCFB8bit;
      if rbCFBblock.IsChecked then ChainingMode := cmCFBblock;
      if rbOFB.IsChecked then ChainingMode := cmOFB;
      if rbCTR.IsChecked then ChainingMode := cmCTR;
      if rbECB.IsChecked then ChainingMode := cmECB;

      if rbZeroPadding.IsChecked then PaddingMode := pmZeroPadding;
      if rbANSIX923.IsChecked then PaddingMode := pmANSIX923;
      if rbISO10126.IsChecked then PaddingMode := pmISO10126;
      if rbISO7816.IsChecked then PaddingMode := pmISO7816;
      if rbPKCS7.IsChecked then PaddingMode := pmPKCS7;
      if rbRandomPadding.IsChecked then PaddingMode := pmRandomPadding;

      if rbANSI.IsChecked then Encoding := TEncoding.ANSI;
      if rbUTF8.IsChecked then Encoding := TEncoding.UTF8;
      if rbUnicode.IsChecked then Encoding := TEncoding.Unicode;

      Key := Encoding.GetBytes(KeyEdit.Text);
      InitVector := Encoding.GetBytes(InitVectorEdit.Text);
    end;

    procedure TMainForm.EncryptButtonClick(Sender: TObject);
    var
      Keysize: integer;
      Encoding: TEncoding;
      ChainingMode: TChainingMode;
      PaddingMode: TPaddingMode;
      Key, InitVector, Data, Crypt: TBytes;
    begin
      GetOptions(Key, KeySize, InitVector, Encoding, ChainingMode, PaddingMode);
      Data := Encoding.GetBytes(DataMemo.Text);
      EncryptAES(Data, Crypt, Key, KeySize, InitVector, ChainingMode, PaddingMode);
      EncryptedMemo.Text := TNetEncoding.Base64.EncodeBytesToString(Crypt);
    end;

    procedure TMainForm.DecryptButtonClick(Sender: TObject);
    var
      Keysize: integer;
      Encoding: TEncoding;
      ChainingMode: TChainingMode;
      PaddingMode: TPaddingMode;
      Key, InitVector, Data, Crypt: TBytes;
    begin
      GetOptions(Key, KeySize, InitVector, Encoding, ChainingMode, PaddingMode);
      Crypt := TNetEncoding.Base64.DecodeStringToBytes(EncryptedMemo.Text);
      DecryptAES(Crypt, Data, Key, KeySize, InitVector, ChainingMode, PaddingMode);
      DecryptedMemo.Text := Encoding.GetString(Data);
    end;

    end.
于 2017-04-24T15:11:48.867 回答
2

Android 字符串从位置 0 开始。您可以使用low(Data)它将返回字符串的第一个字符，库内部也使用位置 1 的字符串，它不会在 android 或 ios 中运行。对于多平台，我们不应该使用for i:=1 to length(string)，而是应该使用for l in string

我认为LockBox3应该可以解决您的问题。

于 2017-04-20T19:51:52.653 回答