diff --git a/mpi/mpi-internal.h b/mpi/mpi-internal.h
index fd44c0a8..4111d905 100644
--- a/mpi/mpi-internal.h
+++ b/mpi/mpi-internal.h
@@ -1,296 +1,299 @@
/* mpi-internal.h - Internal to the Multi Precision Integers
* Copyright (C) 1994, 1996, 1998, 2000, 2002,
* 2003 Free Software Foundation, Inc.
*
* This file is part of Libgcrypt.
*
* Libgcrypt is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* Libgcrypt is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
*
* Note: This code is heavily based on the GNU MP Library.
* Actually it's the same code with only minor changes in the
* way the data is stored; this is to support the abstraction
* of an optional secure memory allocation which may be used
* to avoid revealing of sensitive data due to paging etc.
*/
#ifndef G10_MPI_INTERNAL_H
#define G10_MPI_INTERNAL_H
#include "mpi-asm-defs.h"
#ifndef BITS_PER_MPI_LIMB
#if BYTES_PER_MPI_LIMB == SIZEOF_UNSIGNED_INT
typedef unsigned int mpi_limb_t;
typedef signed int mpi_limb_signed_t;
#elif BYTES_PER_MPI_LIMB == SIZEOF_UNSIGNED_LONG
typedef unsigned long int mpi_limb_t;
typedef signed long int mpi_limb_signed_t;
#elif BYTES_PER_MPI_LIMB == SIZEOF_UNSIGNED_LONG_LONG
typedef unsigned long long int mpi_limb_t;
typedef signed long long int mpi_limb_signed_t;
#elif BYTES_PER_MPI_LIMB == SIZEOF_UNSIGNED_SHORT
typedef unsigned short int mpi_limb_t;
typedef signed short int mpi_limb_signed_t;
#else
#error BYTES_PER_MPI_LIMB does not match any C type
#endif
#define BITS_PER_MPI_LIMB (8*BYTES_PER_MPI_LIMB)
#endif /*BITS_PER_MPI_LIMB*/
#include "mpi.h"
/* If KARATSUBA_THRESHOLD is not already defined, define it to a
* value which is good on most machines. */
/* tested 4, 16, 32 and 64, where 16 gave the best performance when
* checking a 768 and a 1024 bit ElGamal signature.
* (wk 22.12.97) */
#ifndef KARATSUBA_THRESHOLD
#define KARATSUBA_THRESHOLD 16
#endif
/* The code can't handle KARATSUBA_THRESHOLD smaller than 2. */
#if KARATSUBA_THRESHOLD < 2
#undef KARATSUBA_THRESHOLD
#define KARATSUBA_THRESHOLD 2
#endif
typedef mpi_limb_t *mpi_ptr_t; /* pointer to a limb */
typedef int mpi_size_t; /* (must be a signed type) */
#define ABS(x) (x >= 0 ? x : -x)
#define MIN(l,o) ((l) < (o) ? (l) : (o))
#define MAX(h,i) ((h) > (i) ? (h) : (i))
#define RESIZE_IF_NEEDED(a,b) \
do { \
if( (a)->alloced < (b) ) \
mpi_resize((a), (b)); \
} while(0)
/* Copy N limbs from S to D. */
#define MPN_COPY( d, s, n) \
do { \
mpi_size_t _i; \
for( _i = 0; _i < (n); _i++ ) \
(d)[_i] = (s)[_i]; \
} while(0)
#define MPN_COPY_INCR( d, s, n) \
do { \
mpi_size_t _i; \
for( _i = 0; _i < (n); _i++ ) \
(d)[_i] = (s)[_i]; \
} while (0)
#define MPN_COPY_DECR( d, s, n ) \
do { \
mpi_size_t _i; \
for( _i = (n)-1; _i >= 0; _i--) \
(d)[_i] = (s)[_i]; \
} while(0)
/* Zero N limbs at D */
#define MPN_ZERO(d, n) \
do { \
int _i; \
for( _i = 0; _i < (n); _i++ ) \
(d)[_i] = 0; \
} while (0)
#define MPN_NORMALIZE(d, n) \
do { \
while( (n) > 0 ) { \
if( (d)[(n)-1] ) \
break; \
(n)--; \
} \
} while(0)
#define MPN_NORMALIZE_NOT_ZERO(d, n) \
do { \
for(;;) { \
if( (d)[(n)-1] ) \
break; \
(n)--; \
} \
} while(0)
#define MPN_MUL_N_RECURSE(prodp, up, vp, size, tspace) \
do { \
if( (size) < KARATSUBA_THRESHOLD ) \
mul_n_basecase (prodp, up, vp, size); \
else \
mul_n (prodp, up, vp, size, tspace); \
} while (0);
/* Divide the two-limb number in (NH,,NL) by D, with DI being the largest
* limb not larger than (2**(2*BITS_PER_MP_LIMB))/D - (2**BITS_PER_MP_LIMB).
* If this would yield overflow, DI should be the largest possible number
* (i.e., only ones). For correct operation, the most significant bit of D
* has to be set. Put the quotient in Q and the remainder in R.
*/
#define UDIV_QRNND_PREINV(q, r, nh, nl, d, di) \
do { \
mpi_limb_t _ql GCC_ATTR_UNUSED; \
mpi_limb_t _q, _r; \
mpi_limb_t _xh, _xl; \
umul_ppmm (_q, _ql, (nh), (di)); \
_q += (nh); /* DI is 2**BITS_PER_MPI_LIMB too small */ \
umul_ppmm (_xh, _xl, _q, (d)); \
sub_ddmmss (_xh, _r, (nh), (nl), _xh, _xl); \
if( _xh ) { \
sub_ddmmss (_xh, _r, _xh, _r, 0, (d)); \
_q++; \
if( _xh) { \
sub_ddmmss (_xh, _r, _xh, _r, 0, (d)); \
_q++; \
} \
} \
if( _r >= (d) ) { \
_r -= (d); \
_q++; \
} \
(r) = _r; \
(q) = _q; \
} while (0)
/*-- mpiutil.c --*/
#define mpi_alloc_limb_space(n,f) _gcry_mpi_alloc_limb_space((n),(f))
mpi_ptr_t _gcry_mpi_alloc_limb_space( unsigned nlimbs, int sec );
void _gcry_mpi_free_limb_space( mpi_ptr_t a, unsigned int nlimbs );
void _gcry_mpi_assign_limb_space( gcry_mpi_t a, mpi_ptr_t ap, unsigned nlimbs );
/*-- mpi-bit.c --*/
#define mpi_rshift_limbs(a,n) _gcry_mpi_rshift_limbs ((a), (n))
#define mpi_lshift_limbs(a,n) _gcry_mpi_lshift_limbs ((a), (n))
void _gcry_mpi_rshift_limbs( gcry_mpi_t a, unsigned int count );
void _gcry_mpi_lshift_limbs( gcry_mpi_t a, unsigned int count );
/*-- mpih-add.c --*/
mpi_limb_t _gcry_mpih_add_1(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr,
mpi_size_t s1_size, mpi_limb_t s2_limb );
mpi_limb_t _gcry_mpih_add_n( mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr,
mpi_ptr_t s2_ptr, mpi_size_t size);
mpi_limb_t _gcry_mpih_add(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr, mpi_size_t s1_size,
mpi_ptr_t s2_ptr, mpi_size_t s2_size);
/*-- mpih-sub.c --*/
mpi_limb_t _gcry_mpih_sub_1( mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr,
mpi_size_t s1_size, mpi_limb_t s2_limb );
mpi_limb_t _gcry_mpih_sub_n( mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr,
mpi_ptr_t s2_ptr, mpi_size_t size);
mpi_limb_t _gcry_mpih_sub(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr, mpi_size_t s1_size,
mpi_ptr_t s2_ptr, mpi_size_t s2_size);
/*-- mpih-cmp.c --*/
int _gcry_mpih_cmp( mpi_ptr_t op1_ptr, mpi_ptr_t op2_ptr, mpi_size_t size );
/*-- mpih-mul.c --*/
struct karatsuba_ctx {
struct karatsuba_ctx *next;
mpi_ptr_t tspace;
unsigned int tspace_nlimbs;
mpi_size_t tspace_size;
mpi_ptr_t tp;
unsigned int tp_nlimbs;
mpi_size_t tp_size;
};
void _gcry_mpih_release_karatsuba_ctx( struct karatsuba_ctx *ctx );
mpi_limb_t _gcry_mpih_addmul_1( mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr,
mpi_size_t s1_size, mpi_limb_t s2_limb);
mpi_limb_t _gcry_mpih_submul_1( mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr,
mpi_size_t s1_size, mpi_limb_t s2_limb);
void _gcry_mpih_mul_n( mpi_ptr_t prodp, mpi_ptr_t up, mpi_ptr_t vp,
mpi_size_t size);
mpi_limb_t _gcry_mpih_mul( mpi_ptr_t prodp, mpi_ptr_t up, mpi_size_t usize,
mpi_ptr_t vp, mpi_size_t vsize);
void _gcry_mpih_sqr_n_basecase( mpi_ptr_t prodp, mpi_ptr_t up, mpi_size_t size );
void _gcry_mpih_sqr_n( mpi_ptr_t prodp, mpi_ptr_t up, mpi_size_t size,
mpi_ptr_t tspace);
void _gcry_mpih_mul_karatsuba_case( mpi_ptr_t prodp,
mpi_ptr_t up, mpi_size_t usize,
mpi_ptr_t vp, mpi_size_t vsize,
struct karatsuba_ctx *ctx );
/*-- mpih-mul_1.c (or xxx/cpu/ *.S) --*/
mpi_limb_t _gcry_mpih_mul_1( mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr,
mpi_size_t s1_size, mpi_limb_t s2_limb);
/*-- mpih-div.c --*/
mpi_limb_t _gcry_mpih_mod_1(mpi_ptr_t dividend_ptr, mpi_size_t dividend_size,
mpi_limb_t divisor_limb);
mpi_limb_t _gcry_mpih_divrem( mpi_ptr_t qp, mpi_size_t qextra_limbs,
mpi_ptr_t np, mpi_size_t nsize,
mpi_ptr_t dp, mpi_size_t dsize);
mpi_limb_t _gcry_mpih_divmod_1( mpi_ptr_t quot_ptr,
mpi_ptr_t dividend_ptr, mpi_size_t dividend_size,
mpi_limb_t divisor_limb);
/*-- mpih-shift.c --*/
mpi_limb_t _gcry_mpih_lshift( mpi_ptr_t wp, mpi_ptr_t up, mpi_size_t usize,
unsigned cnt);
mpi_limb_t _gcry_mpih_rshift( mpi_ptr_t wp, mpi_ptr_t up, mpi_size_t usize,
unsigned cnt);
/*-- mpih-const-time.c --*/
#define mpih_set_cond(w,u,s,o) _gcry_mpih_set_cond ((w),(u),(s),(o))
#define mpih_add_n_cond(w,u,v,s,o) _gcry_mpih_add_n_cond ((w),(u),(v),(s),(o))
#define mpih_sub_n_cond(w,u,v,s,o) _gcry_mpih_sub_n_cond ((w),(u),(v),(s),(o))
#define mpih_swap_cond(u,v,s,o) _gcry_mpih_swap_cond ((u),(v),(s),(o))
#define mpih_abs_cond(w,u,s,o) _gcry_mpih_abs_cond ((w),(u),(s),(o))
+#define mpih_mod(v,vs,u,us) _gcry_mpih_mod ((v),(vs),(u),(us))
void _gcry_mpih_set_cond (mpi_ptr_t wp, mpi_ptr_t up, mpi_size_t usize,
unsigned long op_enable);
mpi_limb_t _gcry_mpih_add_n_cond (mpi_ptr_t wp, mpi_ptr_t up, mpi_ptr_t vp,
mpi_size_t usize, unsigned long op_enable);
mpi_limb_t _gcry_mpih_sub_n_cond (mpi_ptr_t wp, mpi_ptr_t up, mpi_ptr_t vp,
mpi_size_t usize, unsigned long op_enable);
void _gcry_mpih_swap_cond (mpi_ptr_t up, mpi_ptr_t vp, mpi_size_t usize,
unsigned long op_enable);
void _gcry_mpih_abs_cond (mpi_ptr_t wp, mpi_ptr_t up,
mpi_size_t usize, unsigned long op_enable);
+mpi_ptr_t _gcry_mpih_mod (mpi_ptr_t vp, mpi_size_t vsize,
+ mpi_ptr_t up, mpi_size_t usize);
/* Define stuff for longlong.h. */
#define W_TYPE_SIZE BITS_PER_MPI_LIMB
typedef mpi_limb_t UWtype;
typedef unsigned int UHWtype;
#if defined (__GNUC__)
typedef unsigned int UQItype __attribute__ ((mode (QI)));
typedef int SItype __attribute__ ((mode (SI)));
typedef unsigned int USItype __attribute__ ((mode (SI)));
typedef int DItype __attribute__ ((mode (DI)));
typedef unsigned int UDItype __attribute__ ((mode (DI)));
#else
typedef unsigned char UQItype;
typedef long SItype;
typedef unsigned long USItype;
#endif
#ifdef __GNUC__
#include "mpi-inline.h"
#endif
#endif /*G10_MPI_INTERNAL_H*/
diff --git a/mpi/mpih-const-time.c b/mpi/mpih-const-time.c
index ea8d5292..d91bf1a9 100644
--- a/mpi/mpih-const-time.c
+++ b/mpi/mpih-const-time.c
@@ -1,144 +1,182 @@
/* mpih-const-time.c - Constant-time MPI helper functions
* Copyright (C) 2020 g10 Code GmbH
*
* This file is part of Libgcrypt.
*
* Libgcrypt is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* Libgcrypt is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this program; if not, see .
*/
#include
#include
#include
#include "mpi-internal.h"
#include "g10lib.h"
+#define A_LIMB_1 ((mpi_limb_t)1)
+
/*
* W = U when OP_ENABLED=1
* otherwise, W keeps old value
*/
void
_gcry_mpih_set_cond (mpi_ptr_t wp, mpi_ptr_t up, mpi_size_t usize,
unsigned long op_enable)
{
mpi_size_t i;
mpi_limb_t mask = ((mpi_limb_t)0) - op_enable;
mpi_limb_t x;
for (i = 0; i < usize; i++)
{
x = mask & (wp[i] ^ up[i]);
wp[i] = wp[i] ^ x;
}
}
/*
* W = U + V when OP_ENABLED=1
* otherwise, W = U
*/
mpi_limb_t
_gcry_mpih_add_n_cond (mpi_ptr_t wp, mpi_ptr_t up, mpi_ptr_t vp,
mpi_size_t usize, unsigned long op_enable)
{
mpi_size_t i;
mpi_limb_t cy;
mpi_limb_t mask = ((mpi_limb_t)0) - op_enable;
cy = 0;
for (i = 0; i < usize; i++)
{
mpi_limb_t x = up[i] + (vp[i] & mask);
mpi_limb_t cy1 = x < up[i];
mpi_limb_t cy2;
x = x + cy;
cy2 = x < cy;
cy = cy1 | cy2;
wp[i] = x;
}
return cy;
}
/*
* W = U - V when OP_ENABLED=1
* otherwise, W = U
*/
mpi_limb_t
_gcry_mpih_sub_n_cond (mpi_ptr_t wp, mpi_ptr_t up, mpi_ptr_t vp,
mpi_size_t usize, unsigned long op_enable)
{
mpi_size_t i;
mpi_limb_t cy;
mpi_limb_t mask = ((mpi_limb_t)0) - op_enable;
cy = 0;
for (i = 0; i < usize; i++)
{
mpi_limb_t x = up[i] - (vp[i] & mask);
mpi_limb_t cy1 = x > up[i];
mpi_limb_t cy2;
cy2 = x < cy;
x = x - cy;
cy = cy1 | cy2;
wp[i] = x;
}
return cy;
}
/*
* Swap value of U and V when OP_ENABLED=1
* otherwise, no change
*/
void
_gcry_mpih_swap_cond (mpi_ptr_t up, mpi_ptr_t vp, mpi_size_t usize,
unsigned long op_enable)
{
mpi_size_t i;
mpi_limb_t mask = ((mpi_limb_t)0) - op_enable;
for (i = 0; i < usize; i++)
{
mpi_limb_t x = mask & (up[i] ^ vp[i]);
up[i] = up[i] ^ x;
vp[i] = vp[i] ^ x;
}
}
/*
* W = -U when OP_ENABLED=1
* otherwise, W = U
*/
void
_gcry_mpih_abs_cond (mpi_ptr_t wp, mpi_ptr_t up, mpi_size_t usize,
unsigned long op_enable)
{
mpi_size_t i;
mpi_limb_t mask = ((mpi_limb_t)0) - op_enable;
mpi_limb_t cy = op_enable;
for (i = 0; i < usize; i++)
{
mpi_limb_t x = ~up[i] + cy;
cy = (x < ~up[i]);
wp[i] = up[i] ^ (mask & (x ^ up[i]));
}
}
+
+
+/*
+ * Allocating memory for W,
+ * compute W = V % U, then return W
+ */
+mpi_ptr_t
+_gcry_mpih_mod (mpi_ptr_t vp, mpi_size_t vsize,
+ mpi_ptr_t up, mpi_size_t usize)
+{
+ int secure;
+ mpi_ptr_t rp;
+ mpi_size_t i;
+
+ secure = _gcry_is_secure (vp);
+ rp = mpi_alloc_limb_space (usize, secure);
+ MPN_ZERO (rp, usize);
+
+ for (i = 0; i < vsize * BITS_PER_MPI_LIMB; i++)
+ {
+ unsigned int j = vsize * BITS_PER_MPI_LIMB - 1 - i;
+ unsigned int limbno = j / BITS_PER_MPI_LIMB;
+ unsigned int bitno = j % BITS_PER_MPI_LIMB;
+ mpi_limb_t limb = vp[limbno];
+ unsigned int the_bit = ((limb & (A_LIMB_1 << bitno)) ? 1 : 0);
+ mpi_limb_t underflow;
+
+ _gcry_mpih_lshift (rp, rp, usize, 1);
+ rp[0] |= the_bit;
+
+ underflow = _gcry_mpih_sub_n (rp, rp, up, usize);
+ mpih_add_n_cond (rp, rp, up, usize, underflow);
+ }
+
+ return rp;
+}