steelcrypt/src/crypto_core_types.adb

116 lines
3.3 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 Crypto_Core_Types is
function To_Hex(A : u8) return String is
S : String(1 .. 2);
Hex_Table : constant array (0 .. 15) of Character :=
( '0', '1', '2', '3',
'4', '5', '6', '7',
'8', '9', 'a', 'b',
'c', 'd', 'e', 'f');
begin
S(1) := Hex_Table(Integer(Shift_Right(A, 4)));
S(2) := Hex_Table(Integer(A and 16#0f#));
return S;
end To_Hex;
function To_Hex(A : u8_Array) return String is
S : String(1 .. A'Length * 2);
k : Positive := 1;
begin
for i in A'Range loop
S(k .. k + 1) := To_Hex(A(i));
k := k + 2;
end loop;
return S;
end To_Hex;
function Get_Hex_Value(C : Character) return Integer is
r : Integer;
begin
case C is
when '0' => r := 0;
when '1' => r := 1;
when '2' => r := 2;
when '3' => r := 3;
when '4' => r := 4;
when '5' => r := 5;
when '6' => r := 6;
when '7' => r := 7;
when '8' => r := 8;
when '9' => r := 9;
when 'A' => r := 10;
when 'a' => r := 10;
when 'B' => r := 11;
when 'b' => r := 11;
when 'C' => r := 12;
when 'c' => r := 12;
when 'D' => r := 13;
when 'd' => r := 13;
when 'E' => r := 14;
when 'e' => r := 14;
when 'F' => r := 15;
when 'f' => r := 15;
when others => r:= -1;
end case;
return r;
end;
function From_Hex(S : String) return u8_Array is
A : u8_Array(1 .. (S'Length + 1) / 2);
C : Character;
V : Integer range -1 .. 15;
Index : Positive := 1;
Inside : Boolean := False;
begin
for i in S'Range loop
C := S(i);
if C /= ' ' and then C /= '_' then
V := Get_Hex_Value(C);
if V = -1 then
raise Format_Violation;
else
if Inside then
A(Index) := A(Index) or u8(V);
Inside := False;
Index := Index + 1;
else
A(Index) := Shift_Left(u8(V), 4);
Inside := True;
end if;
end if;
end if;
end loop;
return A;
end From_Hex;
function From_Ascii(S : String) return u8_Array is
A : u8_Array(1 .. S'Length);
Index : Integer := 1;
begin
for i in S'Range loop
A(Index) := u8(Character'Pos(S(i)));
Index := INdex + 1;
end loop;
return A;
end From_Ascii;
end Crypto_Core_types;