1/* SPDX-License-Identifier: GPL-2.0-or-later */
  2/* mpi-internal.h  -  Internal to the Multi Precision Integers
  3 *	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 the
 10 *	 way the data is stored; this is to support the abstraction
 11 *	 of an optional secure memory allocation which may be used
 12 *	 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_H
 18#define G10_MPI_INTERNAL_H
 19
 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 printk
 28#define log_bug printk
 29
 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 a
 37 * value which is good on most machines.  */
 38
 39/* tested 4, 16, 32 and 64, where 16 gave the best performance when
 40 * checking a 768 and a 1024 bit ElGamal signature.
 41 * (wk 22.12.97) */
 42#ifndef KARATSUBA_THRESHOLD
 43#define KARATSUBA_THRESHOLD 16
 44#endif
 45
 46/* The code can't handle KARATSUBA_THRESHOLD smaller than 2.  */
 47#if KARATSUBA_THRESHOLD < 2
 48#undef KARATSUBA_THRESHOLD
 49#define KARATSUBA_THRESHOLD 2
 50#endif
 51
 52typedef mpi_limb_t *mpi_ptr_t;	/* pointer to a limb */
 53typedef int mpi_size_t;		/* (must be a signed type) */
 54
 55/* Copy N limbs from S to D.  */
 56#define MPN_COPY(d, s, n) \
 57	do {					\
 58		mpi_size_t _i;			\
 59		for (_i = 0; _i < (n); _i++)	\
 60			(d)[_i] = (s)[_i];	\
 61	} while (0)
 62
 63#define MPN_COPY_DECR(d, s, n) \
 64	do {					\
 65		mpi_size_t _i;			\
 66		for (_i = (n)-1; _i >= 0; _i--) \
 67			(d)[_i] = (s)[_i];	\
 68	} while (0)
 69
 70/* Zero N limbs at D */
 71#define MPN_ZERO(d, n) \
 72	do {					\
 73		int  _i;			\
 74		for (_i = 0; _i < (n); _i++)	\
 75			(d)[_i] = 0;		\
 76	} while (0)
 77
 78#define MPN_NORMALIZE(d, n)  \
 79	do {					\
 80		while ((n) > 0) {		\
 81			if ((d)[(n)-1])		\
 82				break;		\
 83			(n)--;			\
 84		}				\
 85	} while (0)
 86
 87#define MPN_MUL_N_RECURSE(prodp, up, vp, size, tspace) \
 88	do {							\
 89		if ((size) < KARATSUBA_THRESHOLD)		\
 90			mul_n_basecase(prodp, up, vp, size);	\
 91		else						\
 92			mul_n(prodp, up, vp, size, tspace);	\
 93	} while (0);
 94
 95/*-- mpiutil.c --*/
 96mpi_ptr_t mpi_alloc_limb_space(unsigned nlimbs);
 97void mpi_free_limb_space(mpi_ptr_t a);
 98void mpi_assign_limb_space(MPI a, mpi_ptr_t ap, unsigned nlimbs);
 99
100static inline mpi_limb_t mpihelp_add_1(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr,
101			 mpi_size_t s1_size, mpi_limb_t s2_limb);
102mpi_limb_t mpihelp_add_n(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr,
103			 mpi_ptr_t s2_ptr, mpi_size_t size);
104static inline mpi_limb_t mpihelp_add(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr, mpi_size_t s1_size,
105		       mpi_ptr_t s2_ptr, mpi_size_t s2_size);
106
107static inline mpi_limb_t mpihelp_sub_1(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr,
108			 mpi_size_t s1_size, mpi_limb_t s2_limb);
109mpi_limb_t mpihelp_sub_n(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr,
110			 mpi_ptr_t s2_ptr, mpi_size_t size);
111static inline mpi_limb_t mpihelp_sub(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr, mpi_size_t s1_size,
112		       mpi_ptr_t s2_ptr, mpi_size_t s2_size);
113
114/*-- mpih-cmp.c --*/
115int mpihelp_cmp(mpi_ptr_t op1_ptr, mpi_ptr_t op2_ptr, mpi_size_t size);
116
117/*-- mpih-mul.c --*/
118
119struct karatsuba_ctx {
120	struct karatsuba_ctx *next;
121	mpi_ptr_t tspace;
122	mpi_size_t tspace_size;
123	mpi_ptr_t tp;
124	mpi_size_t tp_size;
125};
126
127void mpihelp_release_karatsuba_ctx(struct karatsuba_ctx *ctx);
128
129mpi_limb_t mpihelp_addmul_1(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr,
130			    mpi_size_t s1_size, mpi_limb_t s2_limb);
131mpi_limb_t mpihelp_submul_1(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr,
132			    mpi_size_t s1_size, mpi_limb_t s2_limb);
133int mpihelp_mul(mpi_ptr_t prodp, mpi_ptr_t up, mpi_size_t usize,
134		mpi_ptr_t vp, mpi_size_t vsize, mpi_limb_t *_result);
135void mpih_sqr_n_basecase(mpi_ptr_t prodp, mpi_ptr_t up, mpi_size_t size);
136void mpih_sqr_n(mpi_ptr_t prodp, mpi_ptr_t up, mpi_size_t size,
137		mpi_ptr_t tspace);
138
139int mpihelp_mul_karatsuba_case(mpi_ptr_t prodp,
140			       mpi_ptr_t up, mpi_size_t usize,
141			       mpi_ptr_t vp, mpi_size_t vsize,
142			       struct karatsuba_ctx *ctx);
143
144/*-- generic_mpih-mul1.c --*/
145mpi_limb_t mpihelp_mul_1(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr,
146			 mpi_size_t s1_size, mpi_limb_t s2_limb);
147
148/*-- mpih-div.c --*/
149mpi_limb_t mpihelp_divrem(mpi_ptr_t qp, mpi_size_t qextra_limbs,
150			  mpi_ptr_t np, mpi_size_t nsize,
151			  mpi_ptr_t dp, mpi_size_t dsize);
152
153/*-- generic_mpih-[lr]shift.c --*/
154mpi_limb_t mpihelp_lshift(mpi_ptr_t wp, mpi_ptr_t up, mpi_size_t usize,
155			  unsigned cnt);
156mpi_limb_t mpihelp_rshift(mpi_ptr_t wp, mpi_ptr_t up, mpi_size_t usize,
157			  unsigned cnt);
158
159/* Define stuff for longlong.h.  */
160#define W_TYPE_SIZE BITS_PER_MPI_LIMB
161typedef mpi_limb_t UWtype;
162typedef unsigned int UHWtype;
163#if defined(__GNUC__)
164typedef unsigned int UQItype __attribute__ ((mode(QI)));
165typedef int SItype __attribute__ ((mode(SI)));
166typedef unsigned int USItype __attribute__ ((mode(SI)));
167typedef int DItype __attribute__ ((mode(DI)));
168typedef unsigned int UDItype __attribute__ ((mode(DI)));
169#else
170typedef unsigned char UQItype;
171typedef long SItype;
172typedef unsigned long USItype;
173#endif
174
175#ifdef __GNUC__
176#include "mpi-inline.h"
177#endif
178
179#endif /*G10_MPI_INTERNAL_H */