3 * Useful functions for doing DSA
5 * (c) 2008 Straylight/Edgeware
8 /*----- Licensing notice --------------------------------------------------*
10 * This file is part of Catacomb.
12 * Catacomb is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU Library General Public License as
14 * published by the Free Software Foundation; either version 2 of the
15 * License, or (at your option) any later version.
17 * Catacomb is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 * GNU Library General Public License for more details.
22 * You should have received a copy of the GNU Library General Public
23 * License along with Catacomb; if not, write to the Free
24 * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
28 /*----- Header files ------------------------------------------------------*/
32 /*----- Main code ---------------------------------------------------------*/
34 /* --- @dsa_h2n@ --- *
36 * Arguments: @mp *d@ = destination integer
37 * @mp *r@ = order of the DSA group
38 * @const void *h@ = pointer to message hash
39 * @size_t hsz@ = size (in bytes) of the hash output
41 * Returns: Resulting integer.
43 * Use: Converts a hash to an integer in the demented way necessary
44 * for DSA/ECDSA. This is, of course, completely insane, but
48 mp
*dsa_h2n(mp
*d
, mp
*r
, const void *h
, size_t hsz
)
50 size_t n
= mp_bits(r
);
58 d
= mp_loadb(d
, h
, l
);
64 /*----- That's all, folks -------------------------------------------------*/