steelcrypt/src/abstraction/hash_generic.adb

37 lines
1.4 KiB
Ada

-- Copyright (C) 2015 Daniel Otte <bg@nerilex.org>
--
-- 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, either version 3 of the License, or
-- (at your option) any later version.
--
-- 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, see <http://www.gnu.org/licenses/>.
package body Hash_Generic is
procedure Hash(Data : in u8_Array; Digest : out u8_Array; Bits : in Integer := -1) is
Context : Context_T_Intern;
Counter : Natural := Data'Length * 8;
Index : Integer := Data'First;
begin
if Bits >= 0 then
Counter := Bits;
end if;
Initialize(Context);
while Counter > Block_Size_Bits loop
Next_Block(Context, Data(Index .. Index + Block_Size_Bytes - 1));
Index := Index + Block_Size_Bytes;
Counter := Counter - Block_Size_Bits;
end loop;
Last_Block(Context, Data(Index .. Data'Last), Counter);
Get_Digest(Context, Digest);
end;
end Hash_Generic;