File : g-shsh32.ads
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 _ 3 2 --
6 -- --
7 -- S p e c --
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 -- --
19 -- --
20 -- --
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
32 -- This package provides support for the 32-bit FIPS PUB 180-3 functions
33 -- SHA-224 and SHA-256.
34
35 -- This is an internal unit and should not be used directly in applications.
36 -- Use GNAT.SHA224 and GNAT.SHA256 instead.
37
38 with Interfaces;
39 with GNAT.Byte_Swapping;
40 with GNAT.Secure_Hashes.SHA2_Common;
41
42 package GNAT.Secure_Hashes.SHA2_32 is
43
44 subtype Word is Interfaces.Unsigned_32;
45
46 package Hash_State is new Hash_Function_State
47 (Word => Word,
48 Swap => GNAT.Byte_Swapping.Swap4,
49 Hash_Bit_Order => System.High_Order_First);
50 -- SHA-224 and SHA-256 operate on 32-bit big endian words
51
52 K : constant Hash_State.State (0 .. 63) :=
53 (16#428a2f98#, 16#71374491#, 16#b5c0fbcf#, 16#e9b5dba5#,
54 16#3956c25b#, 16#59f111f1#, 16#923f82a4#, 16#ab1c5ed5#,
55 16#d807aa98#, 16#12835b01#, 16#243185be#, 16#550c7dc3#,
56 16#72be5d74#, 16#80deb1fe#, 16#9bdc06a7#, 16#c19bf174#,
57 16#e49b69c1#, 16#efbe4786#, 16#0fc19dc6#, 16#240ca1cc#,
58 16#2de92c6f#, 16#4a7484aa#, 16#5cb0a9dc#, 16#76f988da#,
59 16#983e5152#, 16#a831c66d#, 16#b00327c8#, 16#bf597fc7#,
60 16#c6e00bf3#, 16#d5a79147#, 16#06ca6351#, 16#14292967#,
61 16#27b70a85#, 16#2e1b2138#, 16#4d2c6dfc#, 16#53380d13#,
62 16#650a7354#, 16#766a0abb#, 16#81c2c92e#, 16#92722c85#,
63 16#a2bfe8a1#, 16#a81a664b#, 16#c24b8b70#, 16#c76c51a3#,
64 16#d192e819#, 16#d6990624#, 16#f40e3585#, 16#106aa070#,
65 16#19a4c116#, 16#1e376c08#, 16#2748774c#, 16#34b0bcb5#,
66 16#391c0cb3#, 16#4ed8aa4a#, 16#5b9cca4f#, 16#682e6ff3#,
67 16#748f82ee#, 16#78a5636f#, 16#84c87814#, 16#8cc70208#,
68 16#90befffa#, 16#a4506ceb#, 16#bef9a3f7#, 16#c67178f2#);
69 -- Constants from FIPS PUB 180-3
70
71 function Sigma0 (X : Word) return Word;
72 function Sigma1 (X : Word) return Word;
73 function S0 (X : Word) return Word;
74 function S1 (X : Word) return Word;
75 pragma Inline (Sigma0, Sigma1, S0, S1);
76 -- Elementary functions Sigma^256_0, Sigma^256_1, sigma^256_0, sigma^256_1
77 -- from FIPS PUB 180-3.
78
79 procedure Transform is new SHA2_Common.Transform
80 (Hash_State => Hash_State,
81 K => K,
82 Rounds => 64,
83 Sigma0 => Sigma0,
84 Sigma1 => Sigma1,
85 S0 => S0,
86 S1 => S1);
87
88 SHA224_Init_State : constant Hash_State.State (0 .. 7) :=
89 (0 => 16#c1059ed8#,
90 1 => 16#367cd507#,
91 2 => 16#3070dd17#,
92 3 => 16#f70e5939#,
93 4 => 16#ffc00b31#,
94 5 => 16#68581511#,
95 6 => 16#64f98fa7#,
96 7 => 16#befa4fa4#);
97 SHA256_Init_State : constant Hash_State.State (0 .. 7) :=
98 (0 => 16#6a09e667#,
99 1 => 16#bb67ae85#,
100 2 => 16#3c6ef372#,
101 3 => 16#a54ff53a#,
102 4 => 16#510e527f#,
103 5 => 16#9b05688c#,
104 6 => 16#1f83d9ab#,
105 7 => 16#5be0cd19#);
106 -- Initialization vectors from FIPS PUB 180-3
107
108 end GNAT.Secure_Hashes.SHA2_32;