--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hedgewars/uSHA.pas	Thu Jan 11 20:45:59 2007 +0000
@@ -0,0 +1,143 @@
+(*
+ * Hedgewars, a worms-like 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);
+function  SHA1Final(Context: TSHA1Context): TSHA1Digest;
+
+implementation
+
+function rol(x: LongWord; y: Byte): LongWord;
+begin
+  Result:= (X shl y) or (X shr (32 - y))
+end;
+
+function Ft(t, b, c, d: LongWord): LongWord;
+begin
+case t of
+      0..19: Result := (b and c) or ((not b) and d);
+     20..39: Result :=  b xor c xor d;
+     40..59: Result := (b and c) or (b and d) or (c and d);
+     else    Result :=  b xor c xor d;
+  end;
+end;
+
+function Kt(t: Byte): LongWord;
+begin
+  case t of
+     0..19: Result := $5A827999;
+    20..39: Result := $6ED9EBA1;
+    40..59: Result := $8F1BBCDC;
+  else
+    Result := $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: integer;
+begin
+for i:= 0 to Pred(Length) do
+    begin
+    Context.Buf[Context.CurrLength]:= PByteArray(Buf)^[i];
+    inc(Context.CurrLength);
+    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);
+move(Context.H, Result, sizeof(TSHA1Digest));
+FillChar(Context, sizeof(Context), 0)
+end;
+
+end.