适合Delphi2009的MD5单元

unit MD5;

interface
uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, StdCtrls;
type
MD5Count = array[0..1] of DWORD;
MD5State = array[0..3] of DWORD;
MD5Block = array[0..15] of DWORD;
MD5CBits = array[0..7] of Byte;
MD5Digest = array[0..15] of Byte;
MD5Buffer = array[0..63] of Byte;
MD5Context = record
    State: MD5State;
    Count: MD5Count;
    Buffer: MD5Buffer;
end;

procedure MD5Init(var Context: MD5Context);
procedure MD5Update(var Context: MD5Context; Input: PAnsiChar; Length: longword);
procedure MD5Final(var Context: MD5Context; var Digest: MD5Digest);
function MD5File(N:String): MD5Digest;
function MD5Print(D: MD5Digest): AnsiString;
function MD5F(FileName:AnsiString): AnsiString;
function MD5S(Str: AnsiString): AnsiString;
//MD5F为计算文件的MD5值,MD5S为计算字符串的MD5值!
var
PADDING: MD5Buffer = (
    $80, $00, $00, $00, $00, $00, $00, $00,
    $00, $00, $00, $00, $00, $00, $00, $00,
    $00, $00, $00, $00, $00, $00, $00, $00,
    $00, $00, $00, $00, $00, $00, $00, $00,
    $00, $00, $00, $00, $00, $00, $00, $00,
    $00, $00, $00, $00, $00, $00, $00, $00,
    $00, $00, $00, $00, $00, $00, $00, $00,
    $00, $00, $00, $00, $00, $00, $00, $00);
implementation

function F(x, y, z: DWORD): DWORD;
begin
Result := (x and y) or ((not x) and z);
end;

function G(x, y, z: DWORD): DWORD;
begin
Result := (x and z) or (y and (not z));
end;

function H(x, y, z: DWORD): DWORD;
begin
Result := x xor y xor z;
end;

function I(x, y, z: DWORD): DWORD;
begin
Result := y xor (x or (not z));
end;

procedure rot(var x: DWORD; n: BYTE);
begin
x := (x shl n) or (x shr (32 - n));
end;

procedure FF(var a: DWORD; b, c, d, x: DWORD; s: BYTE; ac: DWORD);
begin
inc(a, F(b, c, d) + x + ac);
rot(a, s);
inc(a, b);
end;

procedure GG(var a: DWORD; b, c, d, x: DWORD; s: BYTE; ac: DWORD);
begin
inc(a, G(b, c, d) + x + ac);
rot(a, s);
inc(a, b);
end;

procedure HH(var a: DWORD; b, c, d, x: DWORD; s: BYTE; ac: DWORD);
begin
inc(a, H(b, c, d) + x + ac);
rot(a, s);
inc(a, b);
end;

procedure II(var a: DWORD; b, c, d, x: DWORD; s: BYTE; ac: DWORD);
begin
inc(a, I(b, c, d) + x + ac);
rot(a, s);
inc(a, b);
end;

procedure Encode(Source, Target: pointer; Count: longword);
var
S: PByte;
T: PDWORD;
I: longword;
begin
S := Source;
T := Target;
for I := 1 to Count div 4 do begin
    T^ := S^;
    inc(S);
    T^ := T^ or (S^ shl 8);
    inc(S);
    T^ := T^ or (S^ shl 16);
    inc(S);
    T^ := T^ or (S^ shl 24);
    inc(S);
    inc(T);
end;
end;

procedure Decode(Source, Target: pointer; Count: longword);
var
S: PDWORD;
T: PByte;
I: longword;
begin
S := Source;
T := Target;
for I := 1 to Count do begin
    T^ := S^ and $ff;
    inc(T);
    T^ := (S^ shr 8) and $ff;
    inc(T);
    T^ := (S^ shr 16) and $ff;
    inc(T);
    T^ := (S^ shr 24) and $ff;
    inc(T);
    inc(S);
end;
end;

procedure Transform(Buffer: pointer; var State: MD5State);
var
a, b, c, d: DWORD;
Block: MD5Block;
begin
Encode(Buffer, @Block, 64);
a := State[0];
b := State[1];
c := State[2];
d := State[3];
FF (a, b, c, d, Block[ 0], 7, $d76aa478);
FF (d, a, b, c, Block[ 1], 12, $e8c7b756);
FF (c, d, a, b, Block[ 2], 17, $242070db);
FF (b, c, d, a, Block[ 3], 22, $c1bdceee);
FF (a, b, c, d, Block[ 4], 7, $f57c0faf);
FF (d, a, b, c, Block[ 5], 12, $4787c62a);
FF (c, d, a, b, Block[ 6], 17, $a8304613);
FF (b, c, d, a, Block[ 7], 22, $fd469501);
FF (a, b, c, d, Block[ 8], 7, $698098d8);
FF (d, a, b, c, Block[ 9], 12, $8b44f7af);
FF (c, d, a, b, Block[10], 17, $ffff5bb1);
FF (b, c, d, a, Block[11], 22, $895cd7be);
FF (a, b, c, d, Block[12], 7, $6b901122);
FF (d, a, b, c, Block[13], 12, $fd987193);
FF (c, d, a, b, Block[14], 17, $a679438e);
FF (b, c, d, a, Block[15], 22, $49b40821);
GG (a, b, c, d, Block[ 1], 5, $f61e2562);
GG (d, a, b, c, Block[ 6], 9, $c040b340);
GG (c, d, a, b, Block[11], 14, $265e5a51);
GG (b, c, d, a, Block[ 0], 20, $e9b6c7aa);
GG (a, b, c, d, Block[ 5], 5, $d62f105d);
GG (d, a, b, c, Block[10], 9, $2441453);
GG (c, d, a, b, Block[15], 14, $d8a1e681);
GG (b, c, d, a, Block[ 4], 20, $e7d3fbc8);
GG (a, b, c, d, Block[ 9], 5, $21e1cde6);
GG (d, a, b, c, Block[14], 9, $c33707d6);
GG (c, d, a, b, Block[ 3], 14, $f4d50d87);
GG (b, c, d, a, Block[ 8], 20, $455a14ed);
GG (a, b, c, d, Block[13], 5, $a9e3e905);
GG (d, a, b, c, Block[ 2], 9, $fcefa3f8);
GG (c, d, a, b, Block[ 7], 14, $676f02d9);
GG (b, c, d, a, Block[12], 20, $8d2a4c8a);
HH (a, b, c, d, Block[ 5], 4, $fffa3942);
HH (d, a, b, c, Block[ 8], 11, $8771f681);
HH (c, d, a, b, Block[11], 16, $6d9d6122);
HH (b, c, d, a, Block[14], 23, $fde5380c);
HH (a, b, c, d, Block[ 1], 4, $a4beea44);
HH (d, a, b, c, Block[ 4], 11, $4bdecfa9);
HH (c, d, a, b, Block[ 7], 16, $f6bb4b60);
HH (b, c, d, a, Block[10], 23, $bebfbc70);
HH (a, b, c, d, Block[13], 4, $289b7ec6);
HH (d, a, b, c, Block[ 0], 11, $eaa127fa);
HH (c, d, a, b, Block[ 3], 16, $d4ef3085);
HH (b, c, d, a, Block[ 6], 23, $4881d05);
HH (a, b, c, d, Block[ 9], 4, $d9d4d039);
HH (d, a, b, c, Block[12], 11, $e6db99e5);
HH (c, d, a, b, Block[15], 16, $1fa27cf8);
HH (b, c, d, a, Block[ 2], 23, $c4ac5665);
II (a, b, c, d, Block[ 0], 6, $f4292244);
II (d, a, b, c, Block[ 7], 10, $432aff97);
II (c, d, a, b, Block[14], 15, $ab9423a7);
II (b, c, d, a, Block[ 5], 21, $fc93a039);
II (a, b, c, d, Block[12], 6, $655b59c3);
II (d, a, b, c, Block[ 3], 10, $8f0ccc92);
II (c, d, a, b, Block[10], 15, $ffeff47d);
II (b, c, d, a, Block[ 1], 21, $85845dd1);
II (a, b, c, d, Block[ 8], 6, $6fa87e4f);
II (d, a, b, c, Block[15], 10, $fe2ce6e0);
II (c, d, a, b, Block[ 6], 15, $a3014314);
II (b, c, d, a, Block[13], 21, $4e0811a1);
II (a, b, c, d, Block[ 4], 6, $f7537e82);
II (d, a, b, c, Block[11], 10, $bd3af235);
II (c, d, a, b, Block[ 2], 15, $2ad7d2bb);
II (b, c, d, a, Block[ 9], 21, $eb86d391);
inc(State[0], a);
inc(State[1], b);
inc(State[2], c);
inc(State[3], d);
end;

procedure MD5Init(var Context: MD5Context);
begin
with Context do begin
    State[0] := $67452301;
    State[1] := $efcdab89;
    State[2] := $98badcfe;
    State[3] := $10325476;
    Count[0] := 0;
    Count[1] := 0;
    ZeroMemory(@Buffer, SizeOf(MD5Buffer));
end;
end;

procedure MD5Update(var Context: MD5Context; Input: PAnsiChar; Length: longword);
var
Index: longword;
PartLen: longword;
I: longword;
begin
with Context do begin
    Index := (Count[0] shr 3) and $3f;
    inc(Count[0], Length shl 3);
    if Count[0] < (Length shl 3) then inc(Count[1]);
    inc(Count[1], Length shr 29);
end;
PartLen := 64 - Index;
if Length >= PartLen then begin
    CopyMemory(@Context.Buffer[Index], Input, PartLen);
    Transform(@Context.Buffer, Context.State);
    I := PartLen;
    while I + 63 < Length do begin
      Transform(@Input[I], Context.State);
      inc(I, 64);
    end;
    Index := 0;
end else I := 0;
CopyMemory(@Context.Buffer[Index], @Input[I], Length - I);
end;

procedure MD5Final(var Context: MD5Context; var Digest: MD5Digest);
var
Bits: MD5CBits;
Index: longword;
PadLen: longword;
begin
Decode(@Context.Count, @Bits, 2);
Index := (Context.Count[0] shr 3) and $3f;
if Index < 56 then PadLen := 56 - Index else PadLen := 120 - Index;
MD5Update(Context, @PADDING, PadLen);
MD5Update(Context, @Bits, 8);
Decode(@Context.State, @Digest, 4);
ZeroMemory(@Context, SizeOf(MD5Context));
end;

function MD5String(M: AnsiString): MD5Digest;
var
Context: MD5Context;
begin
MD5Init(Context);
MD5Update(Context, PAnsiChar(M), length(M));
MD5Final(Context, Result);
end;

function MD5File(N:String): MD5Digest;
var
FileHandle: THandle;
MapHandle: THandle;
ViewPointer: pointer;
Context: MD5Context;
begin
MD5Init(Context);
FileHandle := CreateFile(PWideChar(WideString(N)), GENERIC_READ, FILE_SHARE_READ or FILE_SHARE_WRITE,
    nil, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL or FILE_FLAG_SEQUENTIAL_SCAN, 0);
if FileHandle <> INVALID_HANDLE_VALUE then try
    MapHandle := CreateFileMapping(FileHandle, nil, PAGE_READONLY, 0, 0, nil);
    if MapHandle <> 0 then try
      ViewPointer := MapViewOfFile(MapHandle, FILE_MAP_READ, 0, 0, 0);
      if ViewPointer <> nil then try

        MD5Update(Context, ViewPointer, GetFileSize(FileHandle, nil));
      finally
        UnmapViewOfFile(ViewPointer);
      end;
    finally
      CloseHandle(MapHandle);
    end;
finally
    CloseHandle(FileHandle);
end;
MD5Final(Context, Result);
end;

function MD5Print(D: MD5Digest): AnsiString;
var
I: byte;
const
Digits: array[0..15] of Ansichar =
    ('0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f');
begin
Result := '';
for I := 0 to 15 do Result := Result + Digits[(D[I] shr 4) and $0f] + Digits[D[I] and $0f];
end;

function MD5Match(D1, D2: MD5Digest): boolean;
var
I: byte;
begin
I := 0;
Result := TRUE;
while Result and (I < 16) do begin
    Result := D1[I] = D2[I];
    inc(I);
end;
end;

function MD5S(Str: AnsiString): AnsiString;
begin
Result := MD5Print(MD5String(Str));
end;

function MD5F(FileName: AnsiString): AnsiString;
begin
Result := MD5Print(MD5File(string(FileName)));
end;

end.
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适合Delphi2009的MD5单元
