some win32 dll export thingy.
(*
* Hedgewars, a free turn based strategy game
* Copyright (c) 2004-2007 Andrey Korotaev <unC0Rr@gmail.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
*)
unit uSHA;
interface
uses SDLh;
type TSHA1Context = packed record
H: array[0..4] of LongWord;
Length, CurrLength: Int64;
Buf: array[0..63] of byte;
end;
TSHA1Digest = array[0..4] of LongWord;
procedure SHA1Init(var Context: TSHA1Context);
procedure SHA1Update(var Context: TSHA1Context; Buf: PByteArray; Length: LongWord);
procedure SHA1UpdateLongwords(var Context: TSHA1Context; Buf: PLongwordArray; Length: LongWord);
function SHA1Final(Context: TSHA1Context): TSHA1Digest;
implementation
function rol(x: LongWord; y: Byte): LongWord;
begin
rol:= (X shl y) or (X shr (32 - y))
end;
function Ft(t, b, c, d: LongWord): LongWord;
begin
case t of
0..19: Ft := (b and c) or ((not b) and d);
20..39: Ft := b xor c xor d;
40..59: Ft := (b and c) or (b and d) or (c and d);
else Ft := b xor c xor d;
end;
end;
function Kt(t: Byte): LongWord;
begin
case t of
0..19: Kt := $5A827999;
20..39: Kt := $6ED9EBA1;
40..59: Kt := $8F1BBCDC;
else
Kt := $CA62C1D6
end;
end;
procedure SHA1Hash(var Context: TSHA1Context);
var S: array[0..4 ] of LongWord;
W: array[0..79] of LongWord;
i, t: LongWord;
begin
move(Context.H, S, sizeof(S));
for i:= 0 to 15 do
SDLNet_Write32(PLongWordArray(@Context.Buf)^[i], @W[i]);
for i := 16 to 79 do
W[i] := rol(W[i - 3] xor W[i - 8] xor W[i - 14] xor W[i - 16], 1);
for i := 0 to 79 do
begin
t:= rol(S[0], 5) + Ft(i, S[1], S[2], S[3]) + S[4] + W[i] + Kt(i);
S[4]:= S[3];
S[3]:= S[2];
S[2]:= rol(S[1], 30);
S[1]:= S[0];
S[0]:= t
end;
for i := 0 to 4 do
Context.H[i]:= Context.H[i] + S[i]
end;
procedure SHA1Init(var Context: TSHA1Context);
begin
with Context do
begin
Length := 0;
CurrLength:= 0;
H[0]:= $67452301;
H[1]:= $EFCDAB89;
H[2]:= $98BADCFE;
H[3]:= $10325476;
H[4]:= $C3D2E1F0
end
end;
procedure SHA1Update(var Context: TSHA1Context; Buf: PByteArray; Length: LongWord);
var i: Longword;
begin
for i:= 0 to Pred(Length) do
begin
Context.Buf[Context.CurrLength]:= Buf^[i];
inc(Context.CurrLength);
if Context.CurrLength = 64 then
begin
SHA1Hash(Context);
inc(Context.Length, 512);
Context.CurrLength:= 0
end
end
end;
procedure SHA1UpdateLongwords(var Context: TSHA1Context; Buf: PLongwordArray; Length: LongWord);
var i: Longword;
begin
for i:= 0 to Pred(Length div 4) do
begin
SDLNet_Write32(Buf^[i], @Context.Buf[Context.CurrLength]);
inc(Context.CurrLength, 4);
if Context.CurrLength = 64 then
begin
SHA1Hash(Context);
inc(Context.Length, 512);
Context.CurrLength:= 0
end
end
end;
function SHA1Final(Context: TSHA1Context): TSHA1Digest;
var i: LongWord;
begin
Context.Length:= Context.Length + Context.CurrLength shl 3;
Context.Buf[Context.CurrLength]:= $80;
inc(Context.CurrLength);
if Context.CurrLength > 56 then
begin
FillChar(Context.Buf[Context.CurrLength], 64 - Context.CurrLength, 0);
Context.CurrLength:= 64;
SHA1Hash(Context);
Context.CurrLength:=0
end;
FillChar(Context.Buf[Context.CurrLength], 56 - Context.CurrLength, 0);
for i:= 56 to 63 do
Context.Buf[i] := (Context.Length shr ((63 - i) * 8)) and $FF;
SHA1Hash(Context);
for i:= 0 to 4 do SHA1Final[i]:= Context.H[i];
FillChar(Context, sizeof(Context), 0)
end;
end.