Geek Answers Handbook

Delphi - Cannot force HMAC-SHA256 to pass RFC 4231 test vectors

I need to access Amazon RADA services, like the previous question on HMAC-SHA256 in Delphi . "Since it should be in D2010, I'm trying to use the latest version of libeay32.dll to transfer test vectors to RFC 4231:

http://tools.ietf.org/html/rfc4231

Does anyone have a method that passes these tests in Delphi using this library? The code sent by shunty in the message I talked about skips the first two test vectors, as well as the fifth, but it fails in the third and fourth. These vectors have more than 64 bytes, and since the entire URL I need to sign for Amazon is more than 64 bytes, this is a problem. I could not understand that I was doing something wrong. The OpenSSL test is in hmactest.c, but it only checks EVP_md5, and the test vectors are not the same as in the RFC. I need this to work with SHA256 so that I can test the test vectors in the RFC. I use the following constants for tests (the constants are now updated for future viewers to fix my copy and paste errors mentioned in the comments below):

const
  LIBEAY_DLL_NAME = 'libeay32.dll';
  EVP_MAX_MD_SIZE = 64;

  //RFC 4231 Test case 1
  TEST1_KEY: string = '0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b';
  TEST1_DATA: string = '4869205468657265';
  TEST1_DIGEST: string = 'b0344c61d8db38535ca8afceaf0bf12b881dc200c9833da726e9376c2e32cff7';

  //RFC 4231 Test case 2
  TEST2_KEY = '4a656665';
  TEST2_DATA = '7768617420646f2079612077616e7420666f72206e6f7468696e673f';
  TEST2_DIGEST = '5bdcc146bf60754e6a042426089575c75a003f089d2739839dec58b964ec3843';

  //RFC 4231 Test case 3
  TEST3_KEY = 'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa';
  TEST3_DATA = 'dddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddd';
  TEST3_DIGEST = '773ea91e36800e46854db8ebd09181a72959098b3ef8c122d9635514ced565fe';

  //RFC 4231 Test case 4
  TEST4_KEY = '0102030405060708090a0b0c0d0e0f10111213141516171819';
  TEST4_DATA = 'cdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcd';
  TEST4_DIGEST = '82558a389a443c0ea4cc819899f2083a85f0faa3e578f8077a2e3ff46729665b';

  //RFC 4231 Test case 5
  TEST5_KEY = '0c0c0c0c0c0c0c0c0c0c0c0c0c0c0c0c0c0c0c0c';
  TEST5_DATA = '546573742057697468205472756e636174696f6e';
  TEST5_DIGEST = 'a3b6167473100ee06e0c796c2955552b';

, shunty , ( stackoverflow). RAND_seed, RAND_load_file, , :

function TForm1.GetHMAC(const AKey, AData: string): TBytes;
var
  key, data: TBytes;
  md_len: integer;
  res: PByte;
  buf: PInteger;
  rand_val: Integer;
begin
  OpenSSL_add_all_algorithms;

  Randomize;
  rand_val := Random(100);
  GetMem(buf, rand_val);
  try
    RAND_seed(buf, rand_val);

    key := TEncoding.UTF8.GetBytes(AKey);
    data := TEncoding.UTF8.GetBytes(AData);
    md_len := EVP_MAX_MD_SIZE;
    SetLength(Result, md_len);
    res := HMAC(EVP_sha256, @key[0], Length(key), @data[0], Length(data), @result[0], md_len);
    if (res <> nil) then
      SetLength(Result, md_len);

  finally
    FreeMem(buf);
  end;
end;

, , . 3, . bb861233f283aef2ef7aea09785245c9f3c62720c9d04e0c232789f27a586e44, TEST3_DIGEST:

procedure TForm1.btnTestCase3Click(Sender: TObject);
var
  LBytesDigest: TBytes;
  LHashString: string;
  LHexDigest: string;
begin
  LBytesDigest := GetHMAC(HexToStr(TEST3_KEY), HexToStr(TEST3_DATA));

  LHexDigest := LowerCase(BytesToHex(LBytesDigest));

  if LHexDigest = TEST3_DIGEST then begin
    Memo1.Lines.Add('SUCCESS: Matches test case');
    Memo1.Lines.Add(LHexDigest);
  end else begin
    Memo1.Lines.Add('ERROR: Does not match test case');
    Memo1.Lines.Add('Result:    ' + LHexDigest);
    Memo1.Lines.Add('Test Case: ' + TEST3_DIGEST);
  end;
end;

? .NET, , ...

+5
1

D2009 + ( TEncoding), , UnicodeString, Unicode . RFC , . . (Unicode)String, ASCII, , Ansi, UTF-8 ( ).

, TBytes ( Classes.HexToBin()), HMAC TEncoding.UTF8.GetBytes()

function TForm1.GetHMAC(const AKey, AData: TBytes): TBytes; 
var 
  md_len: integer; 
  res: PByte; 
  buf: PInteger; 
  rand_val: Integer; 
begin 
  OpenSSL_add_all_algorithms; 

  Randomize; 
  rand_val := Random(100); 
  GetMem(buf, rand_val); 
  try 
    RAND_seed(buf, rand_val); 
    md_len := EVP_MAX_MD_SIZE; 
    SetLength(Result, md_len); 
    res := HMAC(EVP_sha256, Pointer(AKey), Length(AKey), Pointer(AData), Length(AData), @Result[0], md_len); 
    if (res <> nil) then 
      SetLength(Result, md_len); 
  finally 
    FreeMem(buf); 
  end; 
end; 

function HexToBytes(const S: String): TBytes;
begin
  SetLength(Result, Length(S) div 2);
  SetLength(Result, HexToBin(PChar(S), Pointer(Result), Length(Result)));
en;

procedure TForm1.btnTestCase3Click(Sender: TObject);  
var  
  LBytesDigest: TBytes;  
  LHashString: string;  
  LHexDigest: string;  
begin  
  LBytesDigest := GetHMAC(HexToBytes(TEST3_KEY), HexToBytes(TEST3_DATA));  
  LHexDigest := LowerCase(BytesToHex(LBytesDigest));  
  if LHexDigest = TEST3_DIGEST then begin  
    Memo1.Lines.Add('SUCCESS: Matches test case');  
    Memo1.Lines.Add(LHexDigest);  
  end else begin  
    Memo1.Lines.Add('ERROR: Does not match test case');  
    Memo1.Lines.Add('Result:    ' + LHexDigest);  
    Memo1.Lines.Add('Test Case: ' + TEST3_DIGEST);  
  end;  
end;
+6

More articles:


All Articles