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1/* SPDX-License-Identifier: GPL-2.0-or-later */2/* mpi-internal.h - Internal to the Multi Precision Integers3 * Copyright (C) 1994, 1996 Free Software Foundation, Inc.4 * Copyright (C) 1998, 2000 Free Software Foundation, Inc.5 *6 * This file is part of GnuPG.7 *8 * Note: This code is heavily based on the GNU MP Library.9 * Actually it's the same code with only minor changes in the10 * way the data is stored; this is to support the abstraction11 * of an optional secure memory allocation which may be used12 * to avoid revealing of sensitive data due to paging etc.13 * The GNU MP Library itself is published under the LGPL;14 * however I decided to publish this code under the plain GPL.15 */16 17#ifndef G10_MPI_INTERNAL_H18#define G10_MPI_INTERNAL_H19 20#include <linux/module.h>21#include <linux/kernel.h>22#include <linux/slab.h>23#include <linux/string.h>24#include <linux/mpi.h>25#include <linux/errno.h>26 27#define log_debug printk28#define log_bug printk29 30#define assert(x) \31 do { \32 if (!x) \33 log_bug("failed assertion\n"); \34 } while (0);35 36/* If KARATSUBA_THRESHOLD is not already defined, define it to a37 * value which is good on most machines. */38 39/* tested 4, 16, 32 and 64, where 16 gave the best performance when40 * checking a 768 and a 1024 bit ElGamal signature.41 * (wk 22.12.97) */42#ifndef KARATSUBA_THRESHOLD43#define KARATSUBA_THRESHOLD 1644#endif45 46/* The code can't handle KARATSUBA_THRESHOLD smaller than 2. */47#if KARATSUBA_THRESHOLD < 248#undef KARATSUBA_THRESHOLD49#define KARATSUBA_THRESHOLD 250#endif51 52typedef mpi_limb_t *mpi_ptr_t; /* pointer to a limb */53typedef int mpi_size_t; /* (must be a signed type) */54 55static inline int RESIZE_IF_NEEDED(MPI a, unsigned b)56{57 if (a->alloced < b)58 return mpi_resize(a, b);59 return 0;60}61 62/* Copy N limbs from S to D. */63#define MPN_COPY(d, s, n) \64 do { \65 mpi_size_t _i; \66 for (_i = 0; _i < (n); _i++) \67 (d)[_i] = (s)[_i]; \68 } while (0)69 70#define MPN_COPY_DECR(d, s, n) \71 do { \72 mpi_size_t _i; \73 for (_i = (n)-1; _i >= 0; _i--) \74 (d)[_i] = (s)[_i]; \75 } while (0)76 77/* Zero N limbs at D */78#define MPN_ZERO(d, n) \79 do { \80 int _i; \81 for (_i = 0; _i < (n); _i++) \82 (d)[_i] = 0; \83 } while (0)84 85#define MPN_NORMALIZE(d, n) \86 do { \87 while ((n) > 0) { \88 if ((d)[(n)-1]) \89 break; \90 (n)--; \91 } \92 } while (0)93 94#define MPN_MUL_N_RECURSE(prodp, up, vp, size, tspace) \95 do { \96 if ((size) < KARATSUBA_THRESHOLD) \97 mul_n_basecase(prodp, up, vp, size); \98 else \99 mul_n(prodp, up, vp, size, tspace); \100 } while (0);101 102/* Divide the two-limb number in (NH,,NL) by D, with DI being the largest103 * limb not larger than (2**(2*BITS_PER_MP_LIMB))/D - (2**BITS_PER_MP_LIMB).104 * If this would yield overflow, DI should be the largest possible number105 * (i.e., only ones). For correct operation, the most significant bit of D106 * has to be set. Put the quotient in Q and the remainder in R.107 */108#define UDIV_QRNND_PREINV(q, r, nh, nl, d, di) \109 do { \110 mpi_limb_t _ql __maybe_unused; \111 mpi_limb_t _q, _r; \112 mpi_limb_t _xh, _xl; \113 umul_ppmm(_q, _ql, (nh), (di)); \114 _q += (nh); /* DI is 2**BITS_PER_MPI_LIMB too small */ \115 umul_ppmm(_xh, _xl, _q, (d)); \116 sub_ddmmss(_xh, _r, (nh), (nl), _xh, _xl); \117 if (_xh) { \118 sub_ddmmss(_xh, _r, _xh, _r, 0, (d)); \119 _q++; \120 if (_xh) { \121 sub_ddmmss(_xh, _r, _xh, _r, 0, (d)); \122 _q++; \123 } \124 } \125 if (_r >= (d)) { \126 _r -= (d); \127 _q++; \128 } \129 (r) = _r; \130 (q) = _q; \131 } while (0)132 133 134/*-- mpiutil.c --*/135mpi_ptr_t mpi_alloc_limb_space(unsigned nlimbs);136void mpi_free_limb_space(mpi_ptr_t a);137void mpi_assign_limb_space(MPI a, mpi_ptr_t ap, unsigned nlimbs);138 139static inline mpi_limb_t mpihelp_add_1(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr,140 mpi_size_t s1_size, mpi_limb_t s2_limb);141mpi_limb_t mpihelp_add_n(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr,142 mpi_ptr_t s2_ptr, mpi_size_t size);143static inline mpi_limb_t mpihelp_add(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr, mpi_size_t s1_size,144 mpi_ptr_t s2_ptr, mpi_size_t s2_size);145 146static inline mpi_limb_t mpihelp_sub_1(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr,147 mpi_size_t s1_size, mpi_limb_t s2_limb);148mpi_limb_t mpihelp_sub_n(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr,149 mpi_ptr_t s2_ptr, mpi_size_t size);150static inline mpi_limb_t mpihelp_sub(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr, mpi_size_t s1_size,151 mpi_ptr_t s2_ptr, mpi_size_t s2_size);152 153/*-- mpih-cmp.c --*/154int mpihelp_cmp(mpi_ptr_t op1_ptr, mpi_ptr_t op2_ptr, mpi_size_t size);155 156/*-- mpih-mul.c --*/157 158struct karatsuba_ctx {159 struct karatsuba_ctx *next;160 mpi_ptr_t tspace;161 mpi_size_t tspace_size;162 mpi_ptr_t tp;163 mpi_size_t tp_size;164};165 166void mpihelp_release_karatsuba_ctx(struct karatsuba_ctx *ctx);167 168mpi_limb_t mpihelp_addmul_1(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr,169 mpi_size_t s1_size, mpi_limb_t s2_limb);170mpi_limb_t mpihelp_submul_1(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr,171 mpi_size_t s1_size, mpi_limb_t s2_limb);172int mpihelp_mul(mpi_ptr_t prodp, mpi_ptr_t up, mpi_size_t usize,173 mpi_ptr_t vp, mpi_size_t vsize, mpi_limb_t *_result);174void mpih_sqr_n_basecase(mpi_ptr_t prodp, mpi_ptr_t up, mpi_size_t size);175void mpih_sqr_n(mpi_ptr_t prodp, mpi_ptr_t up, mpi_size_t size,176 mpi_ptr_t tspace);177 178int mpihelp_mul_karatsuba_case(mpi_ptr_t prodp,179 mpi_ptr_t up, mpi_size_t usize,180 mpi_ptr_t vp, mpi_size_t vsize,181 struct karatsuba_ctx *ctx);182 183/*-- generic_mpih-mul1.c --*/184mpi_limb_t mpihelp_mul_1(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr,185 mpi_size_t s1_size, mpi_limb_t s2_limb);186 187/*-- mpih-div.c --*/188mpi_limb_t mpihelp_mod_1(mpi_ptr_t dividend_ptr, mpi_size_t dividend_size,189 mpi_limb_t divisor_limb);190mpi_limb_t mpihelp_divrem(mpi_ptr_t qp, mpi_size_t qextra_limbs,191 mpi_ptr_t np, mpi_size_t nsize,192 mpi_ptr_t dp, mpi_size_t dsize);193mpi_limb_t mpihelp_divmod_1(mpi_ptr_t quot_ptr,194 mpi_ptr_t dividend_ptr, mpi_size_t dividend_size,195 mpi_limb_t divisor_limb);196 197/*-- generic_mpih-[lr]shift.c --*/198mpi_limb_t mpihelp_lshift(mpi_ptr_t wp, mpi_ptr_t up, mpi_size_t usize,199 unsigned cnt);200mpi_limb_t mpihelp_rshift(mpi_ptr_t wp, mpi_ptr_t up, mpi_size_t usize,201 unsigned cnt);202 203/* Define stuff for longlong.h. */204#define W_TYPE_SIZE BITS_PER_MPI_LIMB205typedef mpi_limb_t UWtype;206typedef unsigned int UHWtype;207#if defined(__GNUC__)208typedef unsigned int UQItype __attribute__ ((mode(QI)));209typedef int SItype __attribute__ ((mode(SI)));210typedef unsigned int USItype __attribute__ ((mode(SI)));211typedef int DItype __attribute__ ((mode(DI)));212typedef unsigned int UDItype __attribute__ ((mode(DI)));213#else214typedef unsigned char UQItype;215typedef long SItype;216typedef unsigned long USItype;217#endif218 219#ifdef __GNUC__220#include "mpi-inline.h"221#endif222 223#endif /*G10_MPI_INTERNAL_H */224