1 /* mpi.h - Multi Precision Integers 2 * Copyright (C) 1994, 1996, 1998, 1999, 3 * 2000, 2001 Free Software Foundation, Inc. 4 * 5 * This file is part of GNUPG. 6 * 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. 11 * 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. 16 * 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 20 * 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. 28 */ 29 30 #ifndef G10_MPI_H 31 #define G10_MPI_H 32 33 #include <linux/types.h> 34 #include <linux/scatterlist.h> 35 36 #define BYTES_PER_MPI_LIMB (BITS_PER_LONG / 8) 37 #define BITS_PER_MPI_LIMB BITS_PER_LONG 38 39 typedef unsigned long int mpi_limb_t; 40 typedef signed long int mpi_limb_signed_t; 41 42 struct gcry_mpi { 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 */ 48 /* bit 1: not used */ 49 /* bit 2: the limb is a pointer to some m_alloced data */ 50 mpi_limb_t *d; /* array with the limbs */ 51 }; 52 53 typedef struct gcry_mpi *MPI; 54 55 #define mpi_get_nlimbs(a) ((a)->nlimbs) 56 #define mpi_is_neg(a) ((a)->sign) 57 58 /*-- mpiutil.c --*/ 59 MPI mpi_alloc(unsigned nlimbs); 60 MPI mpi_alloc_secure(unsigned nlimbs); 61 MPI mpi_alloc_like(MPI a); 62 void mpi_free(MPI a); 63 int mpi_resize(MPI a, unsigned nlimbs); 64 int mpi_copy(MPI *copy, const MPI a); 65 void mpi_clear(MPI a); 66 int mpi_set(MPI w, MPI u); 67 int mpi_set_ui(MPI w, ulong u); 68 MPI mpi_alloc_set_ui(unsigned long u); 69 void mpi_m_check(MPI a); 70 void mpi_swap(MPI a, MPI b); 71 72 /*-- mpicoder.c --*/ 73 MPI do_encode_md(const void *sha_buffer, unsigned nbits); 74 MPI mpi_read_raw_data(const void *xbuffer, size_t nbytes); 75 MPI mpi_read_from_buffer(const void *buffer, unsigned *ret_nread); 76 MPI mpi_read_raw_from_sgl(struct scatterlist *sgl, unsigned int len); 77 int mpi_fromstr(MPI val, const char *str); 78 u32 mpi_get_keyid(MPI a, u32 *keyid); 79 void *mpi_get_buffer(MPI a, unsigned *nbytes, int *sign); 80 int mpi_read_buffer(MPI a, uint8_t *buf, unsigned buf_len, unsigned *nbytes, 81 int *sign); 82 void *mpi_get_secure_buffer(MPI a, unsigned *nbytes, int *sign); 83 int mpi_write_to_sgl(MPI a, struct scatterlist *sg, unsigned nbytes, 84 int *sign); 85 86 #define log_mpidump g10_log_mpidump 87 88 /*-- mpi-add.c --*/ 89 int mpi_add_ui(MPI w, MPI u, ulong v); 90 int mpi_add(MPI w, MPI u, MPI v); 91 int mpi_addm(MPI w, MPI u, MPI v, MPI m); 92 int mpi_sub_ui(MPI w, MPI u, ulong v); 93 int mpi_sub(MPI w, MPI u, MPI v); 94 int mpi_subm(MPI w, MPI u, MPI v, MPI m); 95 96 /*-- mpi-mul.c --*/ 97 int mpi_mul_ui(MPI w, MPI u, ulong v); 98 int mpi_mul_2exp(MPI w, MPI u, ulong cnt); 99 int mpi_mul(MPI w, MPI u, MPI v); 100 int mpi_mulm(MPI w, MPI u, MPI v, MPI m); 101 102 /*-- mpi-div.c --*/ 103 ulong mpi_fdiv_r_ui(MPI rem, MPI dividend, ulong divisor); 104 int mpi_fdiv_r(MPI rem, MPI dividend, MPI divisor); 105 int mpi_fdiv_q(MPI quot, MPI dividend, MPI divisor); 106 int mpi_fdiv_qr(MPI quot, MPI rem, MPI dividend, MPI divisor); 107 int mpi_tdiv_r(MPI rem, MPI num, MPI den); 108 int mpi_tdiv_qr(MPI quot, MPI rem, MPI num, MPI den); 109 int mpi_tdiv_q_2exp(MPI w, MPI u, unsigned count); 110 int mpi_divisible_ui(const MPI dividend, ulong divisor); 111 112 /*-- mpi-gcd.c --*/ 113 int mpi_gcd(MPI g, const MPI a, const MPI b); 114 115 /*-- mpi-pow.c --*/ 116 int mpi_pow(MPI w, MPI u, MPI v); 117 int mpi_powm(MPI res, MPI base, MPI exp, MPI mod); 118 119 /*-- mpi-mpow.c --*/ 120 int mpi_mulpowm(MPI res, MPI *basearray, MPI *exparray, MPI mod); 121 122 /*-- mpi-cmp.c --*/ 123 int mpi_cmp_ui(MPI u, ulong v); 124 int mpi_cmp(MPI u, MPI v); 125 126 /*-- mpi-scan.c --*/ 127 int mpi_getbyte(MPI a, unsigned idx); 128 void mpi_putbyte(MPI a, unsigned idx, int value); 129 unsigned mpi_trailing_zeros(MPI a); 130 131 /*-- mpi-bit.c --*/ 132 void mpi_normalize(MPI a); 133 unsigned mpi_get_nbits(MPI a); 134 int mpi_test_bit(MPI a, unsigned n); 135 int mpi_set_bit(MPI a, unsigned n); 136 int mpi_set_highbit(MPI a, unsigned n); 137 void mpi_clear_highbit(MPI a, unsigned n); 138 void mpi_clear_bit(MPI a, unsigned n); 139 int mpi_rshift(MPI x, MPI a, unsigned n); 140 141 /*-- mpi-inv.c --*/ 142 int mpi_invm(MPI x, MPI u, MPI v); 143 144 /* inline functions */ 145 146 /** 147 * mpi_get_size() - returns max size required to store the number 148 * 149 * @a: A multi precision integer for which we want to allocate a bufer 150 * 151 * Return: size required to store the number 152 */ 153 static inline unsigned int mpi_get_size(MPI a) 154 { 155 return a->nlimbs * BYTES_PER_MPI_LIMB; 156 } 157 #endif /*G10_MPI_H */ 158