1------------------------------------------------------------------------------
2--                                                                          --
3--                         GNAT LIBRARY COMPONENTS                          --
4--                                                                          --
5--           G N A T . S E C U R E _ H A S H E S . S H A 2 _ 6 4            --
6--                                                                          --
7--                                 B o d y                                  --
8--                                                                          --
9--           Copyright (C) 2009, Free Software Foundation, Inc.             --
10--                                                                          --
11-- GNAT is free software;  you can  redistribute it  and/or modify it under --
12-- terms of the  GNU General Public License as published  by the Free Soft- --
13-- ware  Foundation;  either version 3,  or (at your option) any later ver- --
14-- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
15-- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
16-- or FITNESS FOR A PARTICULAR PURPOSE.                                     --
17--                                                                          --
18-- As a special exception under Section 7 of GPL version 3, you are granted --
19-- additional permissions described in the GCC Runtime Library Exception,   --
20-- version 3.1, as published by the Free Software Foundation.               --
21--                                                                          --
22-- You should have received a copy of the GNU General Public License and    --
23-- a copy of the GCC Runtime Library Exception along with this program;     --
24-- see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see    --
25-- <http://www.gnu.org/licenses/>.                                          --
26--                                                                          --
27-- GNAT was originally developed  by the GNAT team at  New York University. --
28-- Extensive contributions were provided by Ada Core Technologies Inc.      --
29--                                                                          --
30------------------------------------------------------------------------------
31
32package body GNAT.Secure_Hashes.SHA2_64 is
33
34   use Interfaces;
35
36   ------------
37   -- Sigma0 --
38   ------------
39
40   function Sigma0 (X : Word) return Word is
41   begin
42      return Rotate_Right (X, 28)
43         xor Rotate_Right (X, 34)
44         xor Rotate_Right (X, 39);
45   end Sigma0;
46
47   ------------
48   -- Sigma1 --
49   ------------
50
51   function Sigma1 (X : Word) return Word is
52   begin
53      return Rotate_Right (X, 14)
54         xor Rotate_Right (X, 18)
55         xor Rotate_Right (X, 41);
56   end Sigma1;
57
58   --------
59   -- S0 --
60   --------
61
62   function S0 (X : Word) return Word is
63   begin
64      return Rotate_Right (X, 1)
65         xor Rotate_Right (X, 8)
66         xor Shift_Right  (X, 7);
67   end S0;
68
69   --------
70   -- S1 --
71   --------
72
73   function S1 (X : Word) return Word is
74   begin
75      return Rotate_Right (X, 19)
76         xor Rotate_Right (X, 61)
77         xor Shift_Right  (X, 6);
78   end S1;
79
80end GNAT.Secure_Hashes.SHA2_64;
81