gcc/ada/g-sehash.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 1               --
   6 --                                                                          --
   7 --                                 S p e c                                  --
   8 --                                                                          --
   9 --         Copyright (C) 2002-2009, 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
  32 --  This package provides supporting code for implementation of the SHA-1
  33 --  secure hash function as decsribed in FIPS PUB 180-3. The complete text
  34 --  of FIPS PUB 180-3 can be found at:
  35 --    http://csrc.nist.gov/publications/fips/fips180-3/fips180-3_final.pdf
  36
  37 --  This is an internal unit and should not be used directly in applications.
  38 --  Use GNAT.SHA1 instead.
  39
  40 with GNAT.Byte_Swapping;
  41 with Interfaces;
  42
  43 package GNAT.Secure_Hashes.SHA1 is
  44
  45    package Hash_State is new Hash_Function_State
  46      (Word           => Interfaces.Unsigned_32,
  47       Swap           => GNAT.Byte_Swapping.Swap4,
  48       Hash_Bit_Order => System.High_Order_First);
  49    --  SHA-1 operates on 32-bit big endian words
  50
  51    Block_Words : constant := 16;
  52    --  Messages are processed in chunks of 16 words
  53
  54    procedure Transform
  55      (H : in out Hash_State.State;
  56       M : in out Message_State);
  57    --  Transformation function applied for each block
  58
  59    Initial_State : constant Hash_State.State;
  60    --  Initialization vector
  61
  62 private
  63
  64    Initial_State : constant Hash_State.State :=
  65                      (0 => 16#67452301#,
  66                       1 => 16#EFCDAB89#,
  67                       2 => 16#98BADCFE#,
  68                       3 => 16#10325476#,
  69                       4 => 16#C3D2E1F0#);
  70    --  Initialization vector from FIPS PUB 180-3
  71
  72 end GNAT.Secure_Hashes.SHA1;