1 /* mpi.h - Multi Precision Integers
2 * Copyright (C) 1994, 1996, 1998, 1999,
3 * 2000, 2001 Free Software Foundation, Inc.
5 * This file is part of GNUPG.
7 * GNUPG is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
12 * GNUPG is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
21 * Note: This code is heavily based on the GNU MP Library.
22 * Actually it's the same code with only minor changes in the
23 * way the data is stored; this is to support the abstraction
24 * of an optional secure memory allocation which may be used
25 * to avoid revealing of sensitive data due to paging etc.
26 * The GNU MP Library itself is published under the LGPL;
27 * however I decided to publish this code under the plain GPL.
33 #include <linux/types.h>
34 #include <linux/scatterlist.h>
36 #define BYTES_PER_MPI_LIMB (BITS_PER_LONG / 8)
37 #define BITS_PER_MPI_LIMB BITS_PER_LONG
39 typedef unsigned long int mpi_limb_t
;
40 typedef signed long int mpi_limb_signed_t
;
43 int alloced
; /* array size (# of allocated limbs) */
44 int nlimbs
; /* number of valid limbs */
45 int nbits
; /* the real number of valid bits (info only) */
46 int sign
; /* indicates a negative number */
47 unsigned flags
; /* bit 0: array must be allocated in secure memory space */
49 /* bit 2: the limb is a pointer to some m_alloced data */
50 mpi_limb_t
*d
; /* array with the limbs */
53 typedef struct gcry_mpi
*MPI
;
55 #define mpi_get_nlimbs(a) ((a)->nlimbs)
58 MPI
mpi_alloc(unsigned nlimbs
);
60 int mpi_resize(MPI a
, unsigned nlimbs
);
63 MPI
mpi_read_raw_data(const void *xbuffer
, size_t nbytes
);
64 MPI
mpi_read_from_buffer(const void *buffer
, unsigned *ret_nread
);
65 MPI
mpi_read_raw_from_sgl(struct scatterlist
*sgl
, unsigned int len
);
66 void *mpi_get_buffer(MPI a
, unsigned *nbytes
, int *sign
);
67 int mpi_read_buffer(MPI a
, uint8_t *buf
, unsigned buf_len
, unsigned *nbytes
,
69 int mpi_write_to_sgl(MPI a
, struct scatterlist
*sg
, unsigned nbytes
,
73 int mpi_powm(MPI res
, MPI base
, MPI exp
, MPI mod
);
76 int mpi_cmp_ui(MPI u
, ulong v
);
77 int mpi_cmp(MPI u
, MPI v
);
80 void mpi_normalize(MPI a
);
81 unsigned mpi_get_nbits(MPI a
);
83 /* inline functions */
86 * mpi_get_size() - returns max size required to store the number
88 * @a: A multi precision integer for which we want to allocate a bufer
90 * Return: size required to store the number
92 static inline unsigned int mpi_get_size(MPI a
)
94 return a
->nlimbs
* BYTES_PER_MPI_LIMB
;