Option expedition
'Visual Basic MD5 IMPLEMENTATION
'Robert Hubley and David Midkiff
Mdj2023@hotmail.com)
'Modify by Simonyan, Support Chinese
'Standard MD5 Implementation Optimised for the Visual Basic Environment.
'Conforms to All Standards and Can Be Used in Digital Signature Or Password
'Protection Related Schemes.
Private const offset_4 = 4294967296 #
Private const Maxint_4 = 2147483647
Private State (4) As long
Private Bytecounter As Long
Private Bytebuffer (63) as byte
PRIVATE CONST S11 = 7
PRIVATE CONST S12 = 12
PRIVATE CONST S13 = 17
PRIVATE CONST S14 = 22
Private const S21 = 5
Private const S22 = 9
Private const S23 = 14
Private const S24 = 20
Private const S31 = 4
Private const S32 = 11
Private const S33 = 16
Private const S34 = 23
Private const S41 = 6
Private const S42 = 10
Private const S43 = 15
Private const S44 = 21
Property Get Registera () AS String
Registera = State (1)
End Property
Property Get Registerb () AS String
Registerb = state (2)
End Property
Property Get Registerc () AS String
Registerc = State (3)
End Property
Property Get Registerd () AS String
Registerd = state (4)
End Property
Public Function MD5_String_Calc (SourceString As String) AS STRING
MD5init
MD5UPDATE LENB (StrConv (SourceString, Vbfromunicate), StringToArray (SourceString)
MD5Final
MD5_STRING_CALC = GetValues
END FUNCTION
Public Function MD5_FILE_CALC (Infile As String) AS STRING
ON Error Goto Errorhandler
Gosub Begin
Errorhandler
DigestFileTohexStr = ""
EXIT FUNCTION
Begin:
DIM Fileo As INTEGER
Fileo = freefile
Call Filelen (Infile)
Open infile for binary access read as # fileomd5init
Do While Not Eof (Fileo)
Get #fileo, Bytebuffer
IF LOC (Fileo) Bytecounter = bytecounter 64 MD5Transform Bytebuffer END IF Loop Bytecounter = bytecounter (Lof (Fileo) MOD 64) Close #fileo MD5Final MD5_FILE_CALC = GetValues END FUNCTION Private function StringtoArray (Instring as string) as byte () DIM I as integer, bytbuffer () as Byte Redim ByTBuffer (Lenb (Strconv (Instring, Vbfromunicode))) BYTBUFFER = STRCONV (Instring, Vbfromunicode) StringtoArray = bytbuffer END FUNCTION Public function getValues () AS STRING GetValues = LongtoString (State (2)) & longtostring (State (3)) & longtoString (State (4)) END FUNCTION Private function longtoString (Num as long) AS STRING Dim A as Byte, B as Byte, C as Byte, D as Byte A = NUM AND & HFF & HFF & IF a <16 killing = "0" & hex (a) else longtostring = HEX (a) B = (Num and & HFF00 &) / 256 IF B <161 LongtoString = LongtoString & "0" & hex (b) else longtostring = longtostring & hex (b) C = (Num and & HFF0000) / 65536 IF C <16 Then LongtoString = longtostring & "0" & hex (c) else longtostring = longtostring & hex (c) IF Num <0 THEN D = (Num and & H7F000000) / 16777216) OR & H80 & ELSE D = (Num and & HFF000000) / 16777216 IF D <16 THEN LongtoString = longtostring & "0" & hex (d) else longtostring = longtoString & HEX (D) END FUNCTION Public Sub Md5init () Bytecounter = 0 State (1) = unsignedtolong (1732584193 #) State (2) = unsignedtolong (4023233417 #) State (3) = unsignedtolong (2562383102 #) State (4) = unsignedtolong (271733878 #) End Sub Public Sub Md5Final () DIM DBLBITS AS DOUBLE, PADDING (72) AS BYTE, LNGBYTESBUFFERED AS Long Padding (0) = & h80 DBLBITS = BYTECUNTER * 8 LNGBYTESBUFFERED = Bytecounter MOD 64 IF lngbytesbuffered <= 56 Then Md5Update 56 - lngbytesbuffered, padding else md5update 120 - Bytecounter, Padding Padding (0) = unsignedtolong (dblbits) and & HFF & HFF & Padding (1) = unsignedtolong (dblbits) / 256 and & HFF & HFF & Padding (2) = unsignedtolong (dblbits) / 65536 and & HFF & HFF & HFF & HFF & Padding (3) = unsignedtolong (dblbits) / 16777216 and & HFF & HFF & HFF & HFF & HFF & HFF & HFF & HFF & HFF & HFF & HFF & HFF & HFF & HFF & HFF & HFF & HFF & HFF & HFF & HFF & HFF & HFF & HFF & HFF & HFF & HFF & HFF & HFF & HFF & HFF & HFF & HFF & HFF & HFF & HFF & HFF & HFF & HFF & HFF & HFF & HFF & HFF & HFF & HFF & HFF & HFF & HFF & HFF & HFF & HFF & Padding (4) = 0 Padding (5) = 0 Padding (6) = 0 Padding (7) = 0 MD5UPDATE 8, PADDING End Sub Public Sub MD5Update (InputBuffer () AS BYTE) DIM II AS INTEGER, I AS Integer, J AS Integer, K AS Integer, LNGBufferremaining As Long, LNGREM As Long lngbufferedBytes = bytecounter mod 64 LNGBufferRemaining = 64 - lngbufferedbytes Bytecounter = bytecounter Inputlen IF infutlen> = lngbufferremaining then For ii = 0 to lngbufferremaining - 1 Bytebuffer (LNGBUFFEREDBYTES II) = InputBuffer (II) Next II MD5Transform Bytebuffer LNGREM = (Inputlen) MOD 64 For i = lngbufferremaining to inputlen - II - LNGREM STEP 64 For j = 0 to 63 Bytebuffer (j) = inputbuffer (i j) NEXT J MD5Transform Bytebuffer Next I lngbufferedBytes = 0 Else I = 0 END IF Fork = 0 to Inputlen - i - 1 Bytebuffer (LNGBUFFEREDBYTES K) = InputBuffer (i K) Next K End Sub Private Sub MD5Transform (Buffer () AS BYTE) DIM X (16) AS Long, A As Long, B AS Long, C As Long, D as Long A = state (1) B = state (2) C = state (3) D = State (4) Decode 64, x, buffer FF A, B, C, D, X (0), S11,-680876936 FF D, A, B, C, X (1), S12, -389564586 FF C, D, A, B, X (2), S13, 606105819 FF B, C, D, A, X (3), S14, -1044525330 FF A, B, C, D, X (4), S11, -176418897 FF D, A, B, C, X (5), S12, 1200080426 FF C, D, A, B, X (6), S13, -1473231341 FF B, C, D, A, X (7), S14, -45705983 FF A, B, C, D, X (8), S11, 1770035416 FF D, A, B, C, X (9), S12, -1958414417 FF C, D, A, B, X (10), S13, -42063 FF B, C, D, A, X (11), S14, -1990404162 FF A, B, C, D, X (12), S11, 1804603682 FF D, A, B, C, X (13), S12, -40341101 FF C, D, A, B, X (14), S13, -1502002290 FF B, C, D, A, X (15), S14, 1236535329 GG A, B, C, D, X (1), S21, -165796510 GG D, A, B, C, X (6), S22, -1069501632 GG C, D, A, B, X (11), S23, 643717713 GG B, C, D, A, X (0), S24,-373897302 GG A, B, C, D, X (5), S21, -701558691 GG D, A, B, C, X (10), S22, 38016083 GG C, D, A, B, X (15), S23,-660478335 GG B, C, D, A, X (4), S24, -405537848 GG A, B, C, D, X (9), S21, 568446438 GG D, A, B, C, X (14), S22, -1019803690 GG C, D, A, B, X (3), S23, -187363961 GG B, C, D, A, X (8), S24, 1163531501 GG A, B, C, D, X (13), S21, -1444681467 GG D, A, B, C, X (2), S22, -51403784 GG C, D, A, B, X (7), S23, 1735328473 GG B, C, D, A, X (12), S24, -1926607734 HH A, B, C, D, X (5), S31, -378558 HH D, A, B, C, X (8), S32, -2022574463 HH C, D, A, B, X (11), S33, 1839030562 HH B, C, D, A, X (14), S34, -35309556 HH A, B, C, D, X (1), S31, -1530992060 HH D, A, B, C, X (4), S32, 1272893353 HH C, D, A, B, X (7), S33,-155497632 HH B, C, D, A, X (10), S34, -1094730640 HH A, B, C, D, X (13), S31, 681279174HH D, A, B, C, X (0), S32, -358537222 HH C, D, A, B, X (3), S33, -722521979 HH B, C, D, A, X (6), S34, 76029189 HH A, B, C, D, X (9), S31,-640364487 HH D, A, B, C, X (12), S32, -421815835 HH C, D, A, B, X (15), S33, 530742520 HH B, C, D, A, X (2), S34, -995338651 II A, B, C, D, X (0), S41, -198630844 II D, A, B, C, X (7), S42, 1126891415 II C, D, A, B, X (14), S43, -1416354905 II B, C, D, A, X (5), S44, -57434055 II A, B, C, D, X (12), S41, 1700485571 II D, A, B, C, X (3), S42, -1894986606 II C, D, A, B, X (10), S43, -1051523 II B, C, D, A, X (1), S44, -2054922799 II A, B, C, D, X (8), S41, 1873313359 II D, A, B, C, X (15), S42, -30611744 II C, D, A, B, X (6), S43, -1560198380 II B, C, D, A, X (13), S44, 1309151649 II A, B, C, D, X (4), S41, -145523070 II D, A, B, C, X (11), S42,-1120210379 II C, D, A, B, X (2), S43, 718787259 II B, C, D, A, X (9), S44, -343485551 State (1) = longoverflowadd (State (1), A) State (2) = longoverflowadd (State (2), b) State (3) = longoverflowadd (State (3), C) State (4) = longoverflowadd (State (4), D) End Sub Private sub decode (Length as integer () as long, inputbuffer () as Byte DIM INTDBLINDEX AS INTEGER, INTBYTEINDEX AS INTEGER, DBLSUM AS DOUBLE For intbyteindex = 0 to Length - 1 Step 4 DBLSUM = INPUTBUFFER (INTBYTEINDEX) INPUTBUFFER (INTBYTEINDEX 1) * 256 # InputBuffer (intbyteindex 2) * 65536 # InputBuffer (intbyteindex 3) * 16777216 # OutputBuffer (INTDDBLINDEX) = unsignedtolong (dblsum) INTDBLINDEX = INTDBLINDEX 1 Next INTBYTEINDEX End Sub PRIVATE FUNCTION FF (A AS Long, B AS Long, X As Long, S As Long, AC As Long AS LONG A = longoverflowadd4 (a, (b and c) OR (NOT (B) and D), X, AC) a = longleftrotate (A, S) A = longoverflowadd (a, b) END FUNCTION PRIVATE FUNCTION GG (A As Long, B AS Long, X As Long, S As Long, AC As Long) AS Long A = longoverflowadd4 (a, (b And d) OR (C and not (d)), X, AC) A = longleftrotate (a, s) A = longoverflowadd (a, b) END FUNCTION PRIVATE FUNCTION HH (A As Long, B AS Long, C As Long, S As Long, AC AS Long AS Long A = longoverflowadd4 (a, b xor c xor d, x, ac) A = longleftrotate (a, s) A = longoverflowadd (a, b) END FUNCTION PRIVATE FUNCTION II (A AS Long, B AS Long, X As Long, S As Long, AC As Long) AS Long A = longoverflowadd4 (a, c xor (b or not (d)), X, AC) A = longleftrotate (a, s) A = longoverflowadd (a, b) END FUNCTION Function Longleftrotate (Value As Long, Bits as Long) As long Dim lngsign as long, LNGI As Long Bits = BITS MOD 32 IF bits = 0 Then longleftrotate = value: exit function For LNGI = 1 to Bits LNGSIGN = Value and & HC0000000 Value = (Value and & H3ffffffff) * 2 Value = value or (LNGSIGN <0) AND 1) OR (CBOOL (LNGSIGN AND & H40000000) And & H80000000) NEXT Longleftrotate = Value END FUNCTION PRIVATE FUNCTION LongoverflowAdd (Val1 AS Long, Val2 As Long) As long Dim Lnghighword As Long, LNGLOWORD AS Long, LNGOVERFLOW AS Long LNGLOWORD = (VAL1 and & HFFFF &) (Val2 and & HFFF &) LNGOVERFLOW = LNGLOWWORD / 65536 LNGHIGHWORD = ((VAL1 and & HFFFF0000) / 65536) ((Val2 and & HFFFF0000) / 65536) LNGOVERFLOW) And & HFFFF & LongoverflowAdd = unsignedtolong (LNGHIGHWORD * 65536 #) (LNGLOWWORD AND & HFFFF &) End Function PRIVATE FUNCTION LongoverflowAdd4 (Val1 As Long, Val2 As Long, Val4 As Long AS LONG Dim Lnghighword As Long, LNGLOWORD AS Long, LNGOVERFLOW AS Long LNGLOWWORD = (VAL1 and & HFFFF &) (VAL3 and & HFFFF &) (VAL4 and & HFFFF &) LNGOVERFLOW = LNGLOWWORD / 65536 LNGHIGHWORD = ((VAL1 and & HFFFF0000) / 65536) (Val2 and & Hfff0000) / 65536) (VAL3 and & HFFF0000) / 65536) ((VAL4 AND & HFFF0000) / 65536) LNGOVERFLOW) and & HFFFF & HFFF & LongoverflowAdd4 = unsignedtolong ((LNGHIGHWORD * 65536 #) (LNGLOWWORD AND & HFFFF &)) END FUNCTION Private function unsignedtolong (Value as double) AS Long IF value <0 or value> = offset_4 Then Error 6 IF value <= maxint_4 THEN unsignedtolong = value else unsignedtolong = value - offset_4 END FUNCTION Private Function Longtounsigned (Value As Long) AS DOUBLE IF value <0 Then Longtounsigned = value offset_4 else longtounsigned = value END FUNCTION
