提交 9e235dca 编写于 作者: D Dmitry Kasatkin 提交者: James Morris

Revert "crypto: GnuPG based MPI lib - additional sources (part 4)"

This reverts commit 7e8dec91.

RSA verification implementation does not use this code.
James Morris has asked to remove that.
Signed-off-by: NDmitry Kasatkin <dmitry.kasatkin@intel.com>
Requested-by: NJames Morris <james.l.morris@oracle.com>
Signed-off-by: NJames Morris <james.l.morris@oracle.com>
上级 423b9788
......@@ -361,14 +361,6 @@ config MPILIB
It is used to implement RSA digital signature verification,
which is used by IMA/EVM digital signature extension.
config MPILIB_EXTRA
bool
depends on MPILIB
help
Additional sources of multiprecision maths library from GnuPG.
This code is unnecessary for RSA digital signature verification,
but can be compiled if needed.
config SIGNATURE
tristate
depends on KEYS && CRYPTO
......
......@@ -19,14 +19,3 @@ mpi-y = \
mpih-mul.o \
mpi-pow.o \
mpiutil.o
mpi-$(CONFIG_MPILIB_EXTRA) += \
mpi-add.o \
mpi-div.o \
mpi-cmp.o \
mpi-gcd.o \
mpi-inline.o \
mpi-inv.o \
mpi-mpow.o \
mpi-mul.o \
mpi-scan.o
/* This file defines some basic constants for the MPI machinery. We
* need to define the types on a per-CPU basis, so it is done with
* this file here. */
#define BYTES_PER_MPI_LIMB (SIZEOF_UNSIGNED_LONG)
/* mpi-add.c - MPI functions
* Copyright (C) 1998, 1999, 2000, 2001 Free Software Foundation, Inc.
* Copyright (C) 1994, 1996 Free Software Foundation, Inc.
*
* This file is part of GnuPG.
*
* GnuPG is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* GnuPG 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 General Public License for more details.
*
* You should have received a copy of the GNU 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.
* The GNU MP Library itself is published under the LGPL;
* however I decided to publish this code under the plain GPL.
*/
#include "mpi-internal.h"
/****************
* Add the unsigned integer V to the mpi-integer U and store the
* result in W. U and V may be the same.
*/
int mpi_add_ui(MPI w, const MPI u, unsigned long v)
{
mpi_ptr_t wp, up;
mpi_size_t usize, wsize;
int usign, wsign;
usize = u->nlimbs;
usign = u->sign;
wsign = 0;
/* If not space for W (and possible carry), increase space. */
wsize = usize + 1;
if (w->alloced < wsize)
if (mpi_resize(w, wsize) < 0)
return -ENOMEM;
/* These must be after realloc (U may be the same as W). */
up = u->d;
wp = w->d;
if (!usize) { /* simple */
wp[0] = v;
wsize = v ? 1 : 0;
} else if (!usign) { /* mpi is not negative */
mpi_limb_t cy;
cy = mpihelp_add_1(wp, up, usize, v);
wp[usize] = cy;
wsize = usize + cy;
} else { /* The signs are different. Need exact comparison to determine
* which operand to subtract from which. */
if (usize == 1 && up[0] < v) {
wp[0] = v - up[0];
wsize = 1;
} else {
mpihelp_sub_1(wp, up, usize, v);
/* Size can decrease with at most one limb. */
wsize = usize - (wp[usize - 1] == 0);
wsign = 1;
}
}
w->nlimbs = wsize;
w->sign = wsign;
return 0;
}
int mpi_add(MPI w, MPI u, MPI v)
{
mpi_ptr_t wp, up, vp;
mpi_size_t usize, vsize, wsize;
int usign, vsign, wsign;
if (u->nlimbs < v->nlimbs) { /* Swap U and V. */
usize = v->nlimbs;
usign = v->sign;
vsize = u->nlimbs;
vsign = u->sign;
wsize = usize + 1;
if (RESIZE_IF_NEEDED(w, wsize) < 0)
return -ENOMEM;
/* These must be after realloc (u or v may be the same as w). */
up = v->d;
vp = u->d;
} else {
usize = u->nlimbs;
usign = u->sign;
vsize = v->nlimbs;
vsign = v->sign;
wsize = usize + 1;
if (RESIZE_IF_NEEDED(w, wsize) < 0)
return -ENOMEM;
/* These must be after realloc (u or v may be the same as w). */
up = u->d;
vp = v->d;
}
wp = w->d;
wsign = 0;
if (!vsize) { /* simple */
MPN_COPY(wp, up, usize);
wsize = usize;
wsign = usign;
} else if (usign != vsign) { /* different sign */
/* This test is right since USIZE >= VSIZE */
if (usize != vsize) {
mpihelp_sub(wp, up, usize, vp, vsize);
wsize = usize;
MPN_NORMALIZE(wp, wsize);
wsign = usign;
} else if (mpihelp_cmp(up, vp, usize) < 0) {
mpihelp_sub_n(wp, vp, up, usize);
wsize = usize;
MPN_NORMALIZE(wp, wsize);
if (!usign)
wsign = 1;
} else {
mpihelp_sub_n(wp, up, vp, usize);
wsize = usize;
MPN_NORMALIZE(wp, wsize);
if (usign)
wsign = 1;
}
} else { /* U and V have same sign. Add them. */
mpi_limb_t cy = mpihelp_add(wp, up, usize, vp, vsize);
wp[usize] = cy;
wsize = usize + cy;
if (usign)
wsign = 1;
}
w->nlimbs = wsize;
w->sign = wsign;
return 0;
}
/****************
* Subtract the unsigned integer V from the mpi-integer U and store the
* result in W.
*/
int mpi_sub_ui(MPI w, MPI u, unsigned long v)
{
mpi_ptr_t wp, up;
mpi_size_t usize, wsize;
int usign, wsign;
usize = u->nlimbs;
usign = u->sign;
wsign = 0;
/* If not space for W (and possible carry), increase space. */
wsize = usize + 1;
if (w->alloced < wsize)
if (mpi_resize(w, wsize) < 0)
return -ENOMEM;
/* These must be after realloc (U may be the same as W). */
up = u->d;
wp = w->d;
if (!usize) { /* simple */
wp[0] = v;
wsize = v ? 1 : 0;
wsign = 1;
} else if (usign) { /* mpi and v are negative */
mpi_limb_t cy;
cy = mpihelp_add_1(wp, up, usize, v);
wp[usize] = cy;
wsize = usize + cy;
} else { /* The signs are different. Need exact comparison to determine
* which operand to subtract from which. */
if (usize == 1 && up[0] < v) {
wp[0] = v - up[0];
wsize = 1;
wsign = 1;
} else {
mpihelp_sub_1(wp, up, usize, v);
/* Size can decrease with at most one limb. */
wsize = usize - (wp[usize - 1] == 0);
}
}
w->nlimbs = wsize;
w->sign = wsign;
return 0;
}
int mpi_sub(MPI w, MPI u, MPI v)
{
int rc;
if (w == v) {
MPI vv;
if (mpi_copy(&vv, v) < 0)
return -ENOMEM;
vv->sign = !vv->sign;
rc = mpi_add(w, u, vv);
mpi_free(vv);
} else {
/* fixme: this is not thread-save (we temp. modify v) */
v->sign = !v->sign;
rc = mpi_add(w, u, v);
v->sign = !v->sign;
}
return rc;
}
int mpi_addm(MPI w, MPI u, MPI v, MPI m)
{
if (mpi_add(w, u, v) < 0 || mpi_fdiv_r(w, w, m) < 0)
return -ENOMEM;
return 0;
}
int mpi_subm(MPI w, MPI u, MPI v, MPI m)
{
if (mpi_sub(w, u, v) < 0 || mpi_fdiv_r(w, w, m) < 0)
return -ENOMEM;
return 0;
}
/* mpi-cmp.c - MPI functions
* Copyright (C) 1998, 1999 Free Software Foundation, Inc.
*
* This file is part of GnuPG.
*
* GnuPG is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* GnuPG 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 General Public License for more details.
*
* You should have received a copy of the GNU 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
*/
#include "mpi-internal.h"
int mpi_cmp_ui(MPI u, unsigned long v)
{
mpi_limb_t limb = v;
mpi_normalize(u);
if (!u->nlimbs && !limb)
return 0;
if (u->sign)
return -1;
if (u->nlimbs > 1)
return 1;
if (u->d[0] == limb)
return 0;
else if (u->d[0] > limb)
return 1;
else
return -1;
}
int mpi_cmp(MPI u, MPI v)
{
mpi_size_t usize, vsize;
int cmp;
mpi_normalize(u);
mpi_normalize(v);
usize = u->nlimbs;
vsize = v->nlimbs;
if (!u->sign && v->sign)
return 1;
if (u->sign && !v->sign)
return -1;
if (usize != vsize && !u->sign && !v->sign)
return usize - vsize;
if (usize != vsize && u->sign && v->sign)
return vsize + usize;
if (!usize)
return 0;
cmp = mpihelp_cmp(u->d, v->d, usize);
if (!cmp)
return 0;
if ((cmp < 0 ? 1 : 0) == (u->sign ? 1 : 0))
return 1;
return -1;
}
/* mpi-div.c - MPI functions
* Copyright (C) 1994, 1996 Free Software Foundation, Inc.
* Copyright (C) 1998, 1999, 2000, 2001 Free Software Foundation, Inc.
*
* This file is part of GnuPG.
*
* GnuPG is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* GnuPG 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 General Public License for more details.
*
* You should have received a copy of the GNU 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.
* The GNU MP Library itself is published under the LGPL;
* however I decided to publish this code under the plain GPL.
*/
#include <linux/string.h>
#include "mpi-internal.h"
#include "longlong.h"
int mpi_fdiv_r(MPI rem, MPI dividend, MPI divisor)
{
int rc = -ENOMEM;
int divisor_sign = divisor->sign;
MPI temp_divisor = NULL;
/* We need the original value of the divisor after the remainder has been
* preliminary calculated. We have to copy it to temporary space if it's
* the same variable as REM. */
if (rem == divisor) {
if (mpi_copy(&temp_divisor, divisor) < 0)
goto nomem;
divisor = temp_divisor;
}
if (mpi_tdiv_qr(NULL, rem, dividend, divisor) < 0)
goto nomem;
if (((divisor_sign ? 1 : 0) ^ (dividend->sign ? 1 : 0)) && rem->nlimbs)
if (mpi_add(rem, rem, divisor) < 0)
goto nomem;
rc = 0;
nomem:
if (temp_divisor)
mpi_free(temp_divisor);
return rc;
}
/****************
* Division rounding the quotient towards -infinity.
* The remainder gets the same sign as the denominator.
* rem is optional
*/
ulong mpi_fdiv_r_ui(MPI rem, MPI dividend, ulong divisor)
{
mpi_limb_t rlimb;
rlimb = mpihelp_mod_1(dividend->d, dividend->nlimbs, divisor);
if (rlimb && dividend->sign)
rlimb = divisor - rlimb;
if (rem) {
rem->d[0] = rlimb;
rem->nlimbs = rlimb ? 1 : 0;
}
return rlimb;
}
int mpi_fdiv_q(MPI quot, MPI dividend, MPI divisor)
{
MPI tmp = mpi_alloc(mpi_get_nlimbs(quot));
if (!tmp)
return -ENOMEM;
mpi_fdiv_qr(quot, tmp, dividend, divisor);
mpi_free(tmp);
return 0;
}
int mpi_fdiv_qr(MPI quot, MPI rem, MPI dividend, MPI divisor)
{
int divisor_sign = divisor->sign;
MPI temp_divisor = NULL;
if (quot == divisor || rem == divisor) {
if (mpi_copy(&temp_divisor, divisor) < 0)
return -ENOMEM;
divisor = temp_divisor;
}
if (mpi_tdiv_qr(quot, rem, dividend, divisor) < 0)
goto nomem;
if ((divisor_sign ^ dividend->sign) && rem->nlimbs) {
if (mpi_sub_ui(quot, quot, 1) < 0)
goto nomem;
if (mpi_add(rem, rem, divisor) < 0)
goto nomem;
}
if (temp_divisor)
mpi_free(temp_divisor);
return 0;
nomem:
mpi_free(temp_divisor);
return -ENOMEM;
}
/* If den == quot, den needs temporary storage.
* If den == rem, den needs temporary storage.
* If num == quot, num needs temporary storage.
* If den has temporary storage, it can be normalized while being copied,
* i.e no extra storage should be allocated.
*/
int mpi_tdiv_r(MPI rem, MPI num, MPI den)
{
return mpi_tdiv_qr(NULL, rem, num, den);
}
int mpi_tdiv_qr(MPI quot, MPI rem, MPI num, MPI den)
{
int rc = -ENOMEM;
mpi_ptr_t np, dp;
mpi_ptr_t qp, rp;
mpi_size_t nsize = num->nlimbs;
mpi_size_t dsize = den->nlimbs;
mpi_size_t qsize, rsize;
mpi_size_t sign_remainder = num->sign;
mpi_size_t sign_quotient = num->sign ^ den->sign;
unsigned normalization_steps;
mpi_limb_t q_limb;
mpi_ptr_t marker[5];
int markidx = 0;
if (!dsize)
return -EINVAL;
memset(marker, 0, sizeof(marker));
/* Ensure space is enough for quotient and remainder.
* We need space for an extra limb in the remainder, because it's
* up-shifted (normalized) below. */
rsize = nsize + 1;
if (mpi_resize(rem, rsize) < 0)
goto nomem;
qsize = rsize - dsize; /* qsize cannot be bigger than this. */
if (qsize <= 0) {
if (num != rem) {
rem->nlimbs = num->nlimbs;
rem->sign = num->sign;
MPN_COPY(rem->d, num->d, nsize);
}
if (quot) {
/* This needs to follow the assignment to rem, in case the
* numerator and quotient are the same. */
quot->nlimbs = 0;
quot->sign = 0;
}
return 0;
}
if (quot)
if (mpi_resize(quot, qsize) < 0)
goto nomem;
/* Read pointers here, when reallocation is finished. */
np = num->d;
dp = den->d;
rp = rem->d;
/* Optimize division by a single-limb divisor. */
if (dsize == 1) {
mpi_limb_t rlimb;
if (quot) {
qp = quot->d;
rlimb = mpihelp_divmod_1(qp, np, nsize, dp[0]);
qsize -= qp[qsize - 1] == 0;
quot->nlimbs = qsize;
quot->sign = sign_quotient;
} else
rlimb = mpihelp_mod_1(np, nsize, dp[0]);
rp[0] = rlimb;
rsize = rlimb != 0 ? 1 : 0;
rem->nlimbs = rsize;
rem->sign = sign_remainder;
return 0;
}
if (quot) {
qp = quot->d;
/* Make sure QP and NP point to different objects. Otherwise the
* numerator would be gradually overwritten by the quotient limbs. */
if (qp == np) { /* Copy NP object to temporary space. */
np = marker[markidx++] = mpi_alloc_limb_space(nsize);
if (!np)
goto nomem;
MPN_COPY(np, qp, nsize);
}
} else /* Put quotient at top of remainder. */
qp = rp + dsize;
count_leading_zeros(normalization_steps, dp[dsize - 1]);
/* Normalize the denominator, i.e. make its most significant bit set by
* shifting it NORMALIZATION_STEPS bits to the left. Also shift the
* numerator the same number of steps (to keep the quotient the same!).
*/
if (normalization_steps) {
mpi_ptr_t tp;
mpi_limb_t nlimb;
/* Shift up the denominator setting the most significant bit of
* the most significant word. Use temporary storage not to clobber
* the original contents of the denominator. */
tp = marker[markidx++] = mpi_alloc_limb_space(dsize);
if (!tp)
goto nomem;
mpihelp_lshift(tp, dp, dsize, normalization_steps);
dp = tp;
/* Shift up the numerator, possibly introducing a new most
* significant word. Move the shifted numerator in the remainder
* meanwhile. */
nlimb = mpihelp_lshift(rp, np, nsize, normalization_steps);
if (nlimb) {
rp[nsize] = nlimb;
rsize = nsize + 1;
} else
rsize = nsize;
} else {
/* The denominator is already normalized, as required. Copy it to
* temporary space if it overlaps with the quotient or remainder. */
if (dp == rp || (quot && (dp == qp))) {
mpi_ptr_t tp;
tp = marker[markidx++] = mpi_alloc_limb_space(dsize);
if (!tp)
goto nomem;
MPN_COPY(tp, dp, dsize);
dp = tp;
}
/* Move the numerator to the remainder. */
if (rp != np)
MPN_COPY(rp, np, nsize);
rsize = nsize;
}
q_limb = mpihelp_divrem(qp, 0, rp, rsize, dp, dsize);
if (quot) {
qsize = rsize - dsize;
if (q_limb) {
qp[qsize] = q_limb;
qsize += 1;
}
quot->nlimbs = qsize;
quot->sign = sign_quotient;
}
rsize = dsize;
MPN_NORMALIZE(rp, rsize);
if (normalization_steps && rsize) {
mpihelp_rshift(rp, rp, rsize, normalization_steps);
rsize -= rp[rsize - 1] == 0 ? 1 : 0;
}
rem->nlimbs = rsize;
rem->sign = sign_remainder;
rc = 0;
nomem:
while (markidx)
mpi_free_limb_space(marker[--markidx]);
return rc;
}
int mpi_tdiv_q_2exp(MPI w, MPI u, unsigned count)
{
mpi_size_t usize, wsize;
mpi_size_t limb_cnt;
usize = u->nlimbs;
limb_cnt = count / BITS_PER_MPI_LIMB;
wsize = usize - limb_cnt;
if (limb_cnt >= usize)
w->nlimbs = 0;
else {
mpi_ptr_t wp;
mpi_ptr_t up;
if (RESIZE_IF_NEEDED(w, wsize) < 0)
return -ENOMEM;
wp = w->d;
up = u->d;
count %= BITS_PER_MPI_LIMB;
if (count) {
mpihelp_rshift(wp, up + limb_cnt, wsize, count);
wsize -= !wp[wsize - 1];
} else {
MPN_COPY_INCR(wp, up + limb_cnt, wsize);
}
w->nlimbs = wsize;
}
return 0;
}
/****************
* Check whether dividend is divisible by divisor
* (note: divisor must fit into a limb)
*/
int mpi_divisible_ui(MPI dividend, ulong divisor)
{
return !mpihelp_mod_1(dividend->d, dividend->nlimbs, divisor);
}
/* mpi-gcd.c - MPI functions
* Copyright (C) 1998, 1999, 2000, 2001 Free Software Foundation, Inc.
*
* This file is part of GnuPG.
*
* GnuPG is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* GnuPG 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 General Public License for more details.
*
* You should have received a copy of the GNU 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
*/
#include "mpi-internal.h"
/****************
* Find the greatest common divisor G of A and B.
* Return: true if this 1, false in all other cases
*/
int mpi_gcd(MPI g, const MPI xa, const MPI xb)
{
MPI a = NULL, b = NULL;
if (mpi_copy(&a, xa) < 0)
goto nomem;
if (mpi_copy(&b, xb) < 0)
goto nomem;
/* TAOCP Vol II, 4.5.2, Algorithm A */
a->sign = 0;
b->sign = 0;
while (mpi_cmp_ui(b, 0)) {
if (mpi_fdiv_r(g, a, b) < 0) /* g used as temorary variable */
goto nomem;
if (mpi_set(a, b) < 0)
goto nomem;
if (mpi_set(b, g) < 0)
goto nomem;
}
if (mpi_set(g, a) < 0)
goto nomem;
mpi_free(a);
mpi_free(b);
return !mpi_cmp_ui(g, 1);
nomem:
mpi_free(a);
mpi_free(b);
return -ENOMEM;
}
/* mpi-inline.c
* Copyright (C) 1999, 2000, 2001 Free Software Foundation, Inc.
*
* This file is part of GnuPG.
*
* GnuPG is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* GnuPG 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 General Public License for more details.
*
* You should have received a copy of the GNU 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
*/
/* put the inline functions as real functions into the lib */
#define G10_MPI_INLINE_DECL
#include "mpi-internal.h"
/* always include the header becuase it is only
* included by mpi-internal if __GCC__ is defined but we
* need it here in all cases and the above definition of
* of the macro allows us to do so
*/
#include "mpi-inline.h"
/* mpi-inv.c - MPI functions
* Copyright (C) 1998, 1999, 2000, 2001 Free Software Foundation, Inc.
*
* This file is part of GnuPG.
*
* GnuPG is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* GnuPG 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 General Public License for more details.
*
* You should have received a copy of the GNU 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
*/
#include "mpi-internal.h"
/****************
* Calculate the multiplicative inverse X of A mod N
* That is: Find the solution x for
* 1 = (a*x) mod n
*/
int mpi_invm(MPI x, const MPI a, const MPI n)
{
/* Extended Euclid's algorithm (See TAOPC Vol II, 4.5.2, Alg X)
* modified according to Michael Penk's solution for Exercice 35
* with further enhancement */
MPI u = NULL, v = NULL;
MPI u1 = NULL, u2 = NULL, u3 = NULL;
MPI v1 = NULL, v2 = NULL, v3 = NULL;
MPI t1 = NULL, t2 = NULL, t3 = NULL;
unsigned k;
int sign;
int odd = 0;
int rc = -ENOMEM;
if (mpi_copy(&u, a) < 0)
goto cleanup;
if (mpi_copy(&v, n) < 0)
goto cleanup;
for (k = 0; !mpi_test_bit(u, 0) && !mpi_test_bit(v, 0); k++) {
if (mpi_rshift(u, u, 1) < 0)
goto cleanup;
if (mpi_rshift(v, v, 1) < 0)
goto cleanup;
}
odd = mpi_test_bit(v, 0);
u1 = mpi_alloc_set_ui(1);
if (!u1)
goto cleanup;
if (!odd) {
u2 = mpi_alloc_set_ui(0);
if (!u2)
goto cleanup;
}
if (mpi_copy(&u3, u) < 0)
goto cleanup;
if (mpi_copy(&v1, v) < 0)
goto cleanup;
if (!odd) {
v2 = mpi_alloc(mpi_get_nlimbs(u));
if (!v2)
goto cleanup;
if (mpi_sub(v2, u1, u) < 0)
goto cleanup; /* U is used as const 1 */
}
if (mpi_copy(&v3, v) < 0)
goto cleanup;
if (mpi_test_bit(u, 0)) { /* u is odd */
t1 = mpi_alloc_set_ui(0);
if (!t1)
goto cleanup;
if (!odd) {
t2 = mpi_alloc_set_ui(1);
if (!t2)
goto cleanup;
t2->sign = 1;
}
if (mpi_copy(&t3, v) < 0)
goto cleanup;
t3->sign = !t3->sign;
goto Y4;
} else {
t1 = mpi_alloc_set_ui(1);
if (!t1)
goto cleanup;
if (!odd) {
t2 = mpi_alloc_set_ui(0);
if (!t2)
goto cleanup;
}
if (mpi_copy(&t3, u) < 0)
goto cleanup;
}
do {
do {
if (!odd) {
if (mpi_test_bit(t1, 0) || mpi_test_bit(t2, 0)) { /* one is odd */
if (mpi_add(t1, t1, v) < 0)
goto cleanup;
if (mpi_sub(t2, t2, u) < 0)
goto cleanup;
}
if (mpi_rshift(t1, t1, 1) < 0)
goto cleanup;
if (mpi_rshift(t2, t2, 1) < 0)
goto cleanup;
if (mpi_rshift(t3, t3, 1) < 0)
goto cleanup;
} else {
if (mpi_test_bit(t1, 0))
if (mpi_add(t1, t1, v) < 0)
goto cleanup;
if (mpi_rshift(t1, t1, 1) < 0)
goto cleanup;
if (mpi_rshift(t3, t3, 1) < 0)
goto cleanup;
}
Y4:
;
} while (!mpi_test_bit(t3, 0)); /* while t3 is even */
if (!t3->sign) {
if (mpi_set(u1, t1) < 0)
goto cleanup;
if (!odd)
if (mpi_set(u2, t2) < 0)
goto cleanup;
if (mpi_set(u3, t3) < 0)
goto cleanup;
} else {
if (mpi_sub(v1, v, t1) < 0)
goto cleanup;
sign = u->sign;
u->sign = !u->sign;
if (!odd)
if (mpi_sub(v2, u, t2) < 0)
goto cleanup;
u->sign = sign;
sign = t3->sign;
t3->sign = !t3->sign;
if (mpi_set(v3, t3) < 0)
goto cleanup;
t3->sign = sign;
}
if (mpi_sub(t1, u1, v1) < 0)
goto cleanup;
if (!odd)
if (mpi_sub(t2, u2, v2) < 0)
goto cleanup;
if (mpi_sub(t3, u3, v3) < 0)
goto cleanup;
if (t1->sign) {
if (mpi_add(t1, t1, v) < 0)
goto cleanup;
if (!odd)
if (mpi_sub(t2, t2, u) < 0)
goto cleanup;
}
} while (mpi_cmp_ui(t3, 0)); /* while t3 != 0 */
/* mpi_lshift( u3, k ); */
rc = mpi_set(x, u1);
cleanup:
mpi_free(u1);
mpi_free(v1);
mpi_free(t1);
if (!odd) {
mpi_free(u2);
mpi_free(v2);
mpi_free(t2);
}
mpi_free(u3);
mpi_free(v3);
mpi_free(t3);
mpi_free(u);
mpi_free(v);
return rc;
}
/* mpi-mpow.c - MPI functions
* Copyright (C) 1998, 1999, 2000 Free Software Foundation, Inc.
*
* This file is part of GnuPG.
*
* GnuPG is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* GnuPG 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 General Public License for more details.
*
* You should have received a copy of the GNU 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
*/
#include "mpi-internal.h"
#include "longlong.h"
static int build_index(const MPI *exparray, int k, int i, int t)
{
int j, bitno;
int index = 0;
bitno = t - i;
for (j = k - 1; j >= 0; j--) {
index <<= 1;
if (mpi_test_bit(exparray[j], bitno))
index |= 1;
}
return index;
}
/****************
* RES = (BASE[0] ^ EXP[0]) * (BASE[1] ^ EXP[1]) * ... * mod M
*/
int mpi_mulpowm(MPI res, MPI *basearray, MPI *exparray, MPI m)
{
int rc = -ENOMEM;
int k; /* number of elements */
int t; /* bit size of largest exponent */
int i, j, idx;
MPI *G = NULL; /* table with precomputed values of size 2^k */
MPI tmp = NULL;
for (k = 0; basearray[k]; k++)
;
if (!k) {
pr_emerg("mpi_mulpowm: assert(k) failed\n");
BUG();
}
for (t = 0, i = 0; (tmp = exparray[i]); i++) {
j = mpi_get_nbits(tmp);
if (j > t)
t = j;
}
if (i != k) {
pr_emerg("mpi_mulpowm: assert(i==k) failed\n");
BUG();
}
if (!t) {
pr_emerg("mpi_mulpowm: assert(t) failed\n");
BUG();
}
if (k >= 10) {
pr_emerg("mpi_mulpowm: assert(k<10) failed\n");
BUG();
}
G = kzalloc((1 << k) * sizeof *G, GFP_KERNEL);
if (!G)
goto err_out;
/* and calculate */
tmp = mpi_alloc(mpi_get_nlimbs(m) + 1);
if (!tmp)
goto nomem;
if (mpi_set_ui(res, 1) < 0)
goto nomem;
for (i = 1; i <= t; i++) {
if (mpi_mulm(tmp, res, res, m) < 0)
goto nomem;
idx = build_index(exparray, k, i, t);
if (!(idx >= 0 && idx < (1 << k))) {
pr_emerg("mpi_mulpowm: assert(idx >= 0 && idx < (1<<k)) failed\n");
BUG();
}
if (!G[idx]) {
if (!idx) {
G[0] = mpi_alloc_set_ui(1);
if (!G[0])
goto nomem;
} else {
for (j = 0; j < k; j++) {
if ((idx & (1 << j))) {
if (!G[idx]) {
if (mpi_copy
(&G[idx],
basearray[j]) < 0)
goto nomem;
} else {
if (mpi_mulm
(G[idx], G[idx],
basearray[j],
m) < 0)
goto nomem;
}
}
}
if (!G[idx]) {
G[idx] = mpi_alloc(0);
if (!G[idx])
goto nomem;
}
}
}
if (mpi_mulm(res, tmp, G[idx], m) < 0)
goto nomem;
}
rc = 0;
nomem:
/* cleanup */
mpi_free(tmp);
for (i = 0; i < (1 << k); i++)
mpi_free(G[i]);
kfree(G);
err_out:
return rc;
}
/* mpi-mul.c - MPI functions
* Copyright (C) 1994, 1996 Free Software Foundation, Inc.
* Copyright (C) 1998, 2001 Free Software Foundation, Inc.
*
* This file is part of GnuPG.
*
* GnuPG is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* GnuPG 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 General Public License for more details.
*
* You should have received a copy of the GNU 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.
* The GNU MP Library itself is published under the LGPL;
* however I decided to publish this code under the plain GPL.
*/
#include "mpi-internal.h"
int mpi_mul_ui(MPI prod, MPI mult, unsigned long small_mult)
{
mpi_size_t size, prod_size;
mpi_ptr_t prod_ptr;
mpi_limb_t cy;
int sign;
size = mult->nlimbs;
sign = mult->sign;
if (!size || !small_mult) {
prod->nlimbs = 0;
prod->sign = 0;
return 0;
}
prod_size = size + 1;
if (prod->alloced < prod_size)
if (mpi_resize(prod, prod_size) < 0)
return -ENOMEM;
prod_ptr = prod->d;
cy = mpihelp_mul_1(prod_ptr, mult->d, size, (mpi_limb_t) small_mult);
if (cy)
prod_ptr[size++] = cy;
prod->nlimbs = size;
prod->sign = sign;
return 0;
}
int mpi_mul_2exp(MPI w, MPI u, unsigned long cnt)
{
mpi_size_t usize, wsize, limb_cnt;
mpi_ptr_t wp;
mpi_limb_t wlimb;
int usign, wsign;
usize = u->nlimbs;
usign = u->sign;
if (!usize) {
w->nlimbs = 0;
w->sign = 0;
return 0;
}
limb_cnt = cnt / BITS_PER_MPI_LIMB;
wsize = usize + limb_cnt + 1;
if (w->alloced < wsize)
if (mpi_resize(w, wsize) < 0)
return -ENOMEM;
wp = w->d;
wsize = usize + limb_cnt;
wsign = usign;
cnt %= BITS_PER_MPI_LIMB;
if (cnt) {
wlimb = mpihelp_lshift(wp + limb_cnt, u->d, usize, cnt);
if (wlimb) {
wp[wsize] = wlimb;
wsize++;
}
} else {
MPN_COPY_DECR(wp + limb_cnt, u->d, usize);
}
/* Zero all whole limbs at low end. Do it here and not before calling
* mpn_lshift, not to lose for U == W. */
MPN_ZERO(wp, limb_cnt);
w->nlimbs = wsize;
w->sign = wsign;
return 0;
}
int mpi_mul(MPI w, MPI u, MPI v)
{
int rc = -ENOMEM;
mpi_size_t usize, vsize, wsize;
mpi_ptr_t up, vp, wp;
mpi_limb_t cy;
int usign, vsign, sign_product;
int assign_wp = 0;
mpi_ptr_t tmp_limb = NULL;
if (u->nlimbs < v->nlimbs) { /* Swap U and V. */
usize = v->nlimbs;
usign = v->sign;
up = v->d;
vsize = u->nlimbs;
vsign = u->sign;
vp = u->d;
} else {
usize = u->nlimbs;
usign = u->sign;
up = u->d;
vsize = v->nlimbs;
vsign = v->sign;
vp = v->d;
}
sign_product = usign ^ vsign;
wp = w->d;
/* Ensure W has space enough to store the result. */
wsize = usize + vsize;
if (w->alloced < (size_t) wsize) {
if (wp == up || wp == vp) {
wp = mpi_alloc_limb_space(wsize);
if (!wp)
goto nomem;
assign_wp = 1;
} else {
if (mpi_resize(w, wsize) < 0)
goto nomem;
wp = w->d;
}
} else { /* Make U and V not overlap with W. */
if (wp == up) {
/* W and U are identical. Allocate temporary space for U. */
up = tmp_limb = mpi_alloc_limb_space(usize);
if (!up)
goto nomem;
/* Is V identical too? Keep it identical with U. */
if (wp == vp)
vp = up;
/* Copy to the temporary space. */
MPN_COPY(up, wp, usize);
} else if (wp == vp) {
/* W and V are identical. Allocate temporary space for V. */
vp = tmp_limb = mpi_alloc_limb_space(vsize);
if (!vp)
goto nomem;
/* Copy to the temporary space. */
MPN_COPY(vp, wp, vsize);
}
}
if (!vsize)
wsize = 0;
else {
if (mpihelp_mul(wp, up, usize, vp, vsize, &cy) < 0)
goto nomem;
wsize -= cy ? 0 : 1;
}
if (assign_wp)
mpi_assign_limb_space(w, wp, wsize);
w->nlimbs = wsize;
w->sign = sign_product;
rc = 0;
nomem:
if (tmp_limb)
mpi_free_limb_space(tmp_limb);
return rc;
}
int mpi_mulm(MPI w, MPI u, MPI v, MPI m)
{
if (mpi_mul(w, u, v) < 0)
return -ENOMEM;
return mpi_fdiv_r(w, w, m);
}
/* mpi-scan.c - MPI functions
* Copyright (C) 1998, 1999, 2000, 2001 Free Software Foundation, Inc.
*
* This file is part of GnuPG.
*
* GnuPG is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* GnuPG 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 General Public License for more details.
*
* You should have received a copy of the GNU 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
*/
#include "mpi-internal.h"
#include "longlong.h"
/****************
* Scan through an mpi and return byte for byte. a -1 is returned to indicate
* the end of the mpi. Scanning is done from the lsb to the msb, returned
* values are in the range of 0 .. 255.
*
* FIXME: This code is VERY ugly!
*/
int mpi_getbyte(const MPI a, unsigned idx)
{
int i, j;
unsigned n;
mpi_ptr_t ap;
mpi_limb_t limb;
ap = a->d;
for (n = 0, i = 0; i < a->nlimbs; i++) {
limb = ap[i];
for (j = 0; j < BYTES_PER_MPI_LIMB; j++, n++)
if (n == idx)
return (limb >> j * 8) & 0xff;
}
return -1;
}
/****************
* Put a value at position IDX into A. idx counts from lsb to msb
*/
void mpi_putbyte(MPI a, unsigned idx, int xc)
{
int i, j;
unsigned n;
mpi_ptr_t ap;
mpi_limb_t limb, c;
c = xc & 0xff;
ap = a->d;
for (n = 0, i = 0; i < a->alloced; i++) {
limb = ap[i];
for (j = 0; j < BYTES_PER_MPI_LIMB; j++, n++)
if (n == idx) {
#if BYTES_PER_MPI_LIMB == 4
if (j == 0)
limb = (limb & 0xffffff00) | c;
else if (j == 1)
limb = (limb & 0xffff00ff) | (c << 8);
else if (j == 2)
limb = (limb & 0xff00ffff) | (c << 16);
else
limb = (limb & 0x00ffffff) | (c << 24);
#elif BYTES_PER_MPI_LIMB == 8
if (j == 0)
limb = (limb & 0xffffffffffffff00) | c;
else if (j == 1)
limb =
(limb & 0xffffffffffff00ff) | (c <<
8);
else if (j == 2)
limb =
(limb & 0xffffffffff00ffff) | (c <<
16);
else if (j == 3)
limb =
(limb & 0xffffffff00ffffff) | (c <<
24);
else if (j == 4)
limb =
(limb & 0xffffff00ffffffff) | (c <<
32);
else if (j == 5)
limb =
(limb & 0xffff00ffffffffff) | (c <<
40);
else if (j == 6)
limb =
(limb & 0xff00ffffffffffff) | (c <<
48);
else
limb =
(limb & 0x00ffffffffffffff) | (c <<
56);
#else
#error please enhance this function, its ugly - i know.
#endif
if (a->nlimbs <= i)
a->nlimbs = i + 1;
ap[i] = limb;
return;
}
}
log_bug("index out of range\n");
}
/****************
* Count the number of zerobits at the low end of A
*/
unsigned mpi_trailing_zeros(const MPI a)
{
unsigned n, count = 0;
for (n = 0; n < a->nlimbs; n++) {
if (a->d[n]) {
unsigned nn;
mpi_limb_t alimb = a->d[n];
count_trailing_zeros(nn, alimb);
count += nn;
break;
}
count += BITS_PER_MPI_LIMB;
}
return count;
}
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