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authorHerbert Xu <herbert@gondor.apana.org.au>2023-08-04 17:24:34 +0800
committerHerbert Xu <herbert@gondor.apana.org.au>2023-08-11 19:19:27 +0800
commit2a598d0b2800aa23ba51adcf060cec524aaa63b2 (patch)
treeb7c035f0fa57dab30af2768114f71f64230dac5c /lib/mpi/mpi-bit.c
parent9ae4577bc077a7e32c3c7d442c95bc76865c0f17 (diff)
crypto: lib - Move mpi into lib/crypto
As lib/mpi is mostly used by crypto code, move it under lib/crypto so that patches touching it get directed to the right mailing list. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'lib/mpi/mpi-bit.c')
-rw-r--r--lib/mpi/mpi-bit.c308
1 files changed, 0 insertions, 308 deletions
diff --git a/lib/mpi/mpi-bit.c b/lib/mpi/mpi-bit.c
deleted file mode 100644
index 070ba784c9f1..000000000000
--- a/lib/mpi/mpi-bit.c
+++ /dev/null
@@ -1,308 +0,0 @@
-/* mpi-bit.c - MPI bit level 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"
-#include "longlong.h"
-
-#define A_LIMB_1 ((mpi_limb_t) 1)
-
-/****************
- * Sometimes we have MSL (most significant limbs) which are 0;
- * this is for some reasons not good, so this function removes them.
- */
-void mpi_normalize(MPI a)
-{
- for (; a->nlimbs && !a->d[a->nlimbs - 1]; a->nlimbs--)
- ;
-}
-EXPORT_SYMBOL_GPL(mpi_normalize);
-
-/****************
- * Return the number of bits in A.
- */
-unsigned mpi_get_nbits(MPI a)
-{
- unsigned n;
-
- mpi_normalize(a);
-
- if (a->nlimbs) {
- mpi_limb_t alimb = a->d[a->nlimbs - 1];
- if (alimb)
- n = count_leading_zeros(alimb);
- else
- n = BITS_PER_MPI_LIMB;
- n = BITS_PER_MPI_LIMB - n + (a->nlimbs - 1) * BITS_PER_MPI_LIMB;
- } else
- n = 0;
- return n;
-}
-EXPORT_SYMBOL_GPL(mpi_get_nbits);
-
-/****************
- * Test whether bit N is set.
- */
-int mpi_test_bit(MPI a, unsigned int n)
-{
- unsigned int limbno, bitno;
- mpi_limb_t limb;
-
- limbno = n / BITS_PER_MPI_LIMB;
- bitno = n % BITS_PER_MPI_LIMB;
-
- if (limbno >= a->nlimbs)
- return 0; /* too far left: this is a 0 */
- limb = a->d[limbno];
- return (limb & (A_LIMB_1 << bitno)) ? 1 : 0;
-}
-EXPORT_SYMBOL_GPL(mpi_test_bit);
-
-/****************
- * Set bit N of A.
- */
-void mpi_set_bit(MPI a, unsigned int n)
-{
- unsigned int i, limbno, bitno;
-
- limbno = n / BITS_PER_MPI_LIMB;
- bitno = n % BITS_PER_MPI_LIMB;
-
- if (limbno >= a->nlimbs) {
- for (i = a->nlimbs; i < a->alloced; i++)
- a->d[i] = 0;
- mpi_resize(a, limbno+1);
- a->nlimbs = limbno+1;
- }
- a->d[limbno] |= (A_LIMB_1<<bitno);
-}
-
-/****************
- * Set bit N of A. and clear all bits above
- */
-void mpi_set_highbit(MPI a, unsigned int n)
-{
- unsigned int i, limbno, bitno;
-
- limbno = n / BITS_PER_MPI_LIMB;
- bitno = n % BITS_PER_MPI_LIMB;
-
- if (limbno >= a->nlimbs) {
- for (i = a->nlimbs; i < a->alloced; i++)
- a->d[i] = 0;
- mpi_resize(a, limbno+1);
- a->nlimbs = limbno+1;
- }
- a->d[limbno] |= (A_LIMB_1<<bitno);
- for (bitno++; bitno < BITS_PER_MPI_LIMB; bitno++)
- a->d[limbno] &= ~(A_LIMB_1 << bitno);
- a->nlimbs = limbno+1;
-}
-EXPORT_SYMBOL_GPL(mpi_set_highbit);
-
-/****************
- * clear bit N of A and all bits above
- */
-void mpi_clear_highbit(MPI a, unsigned int n)
-{
- unsigned int limbno, bitno;
-
- limbno = n / BITS_PER_MPI_LIMB;
- bitno = n % BITS_PER_MPI_LIMB;
-
- if (limbno >= a->nlimbs)
- return; /* not allocated, therefore no need to clear bits :-) */
-
- for ( ; bitno < BITS_PER_MPI_LIMB; bitno++)
- a->d[limbno] &= ~(A_LIMB_1 << bitno);
- a->nlimbs = limbno+1;
-}
-
-/****************
- * Clear bit N of A.
- */
-void mpi_clear_bit(MPI a, unsigned int n)
-{
- unsigned int limbno, bitno;
-
- limbno = n / BITS_PER_MPI_LIMB;
- bitno = n % BITS_PER_MPI_LIMB;
-
- if (limbno >= a->nlimbs)
- return; /* Don't need to clear this bit, it's far too left. */
- a->d[limbno] &= ~(A_LIMB_1 << bitno);
-}
-EXPORT_SYMBOL_GPL(mpi_clear_bit);
-
-
-/****************
- * Shift A by COUNT limbs to the right
- * This is used only within the MPI library
- */
-void mpi_rshift_limbs(MPI a, unsigned int count)
-{
- mpi_ptr_t ap = a->d;
- mpi_size_t n = a->nlimbs;
- unsigned int i;
-
- if (count >= n) {
- a->nlimbs = 0;
- return;
- }
-
- for (i = 0; i < n - count; i++)
- ap[i] = ap[i+count];
- ap[i] = 0;
- a->nlimbs -= count;
-}
-
-/*
- * Shift A by N bits to the right.
- */
-void mpi_rshift(MPI x, MPI a, unsigned int n)
-{
- mpi_size_t xsize;
- unsigned int i;
- unsigned int nlimbs = (n/BITS_PER_MPI_LIMB);
- unsigned int nbits = (n%BITS_PER_MPI_LIMB);
-
- if (x == a) {
- /* In-place operation. */
- if (nlimbs >= x->nlimbs) {
- x->nlimbs = 0;
- return;
- }
-
- if (nlimbs) {
- for (i = 0; i < x->nlimbs - nlimbs; i++)
- x->d[i] = x->d[i+nlimbs];
- x->d[i] = 0;
- x->nlimbs -= nlimbs;
- }
- if (x->nlimbs && nbits)
- mpihelp_rshift(x->d, x->d, x->nlimbs, nbits);
- } else if (nlimbs) {
- /* Copy and shift by more or equal bits than in a limb. */
- xsize = a->nlimbs;
- x->sign = a->sign;
- RESIZE_IF_NEEDED(x, xsize);
- x->nlimbs = xsize;
- for (i = 0; i < a->nlimbs; i++)
- x->d[i] = a->d[i];
- x->nlimbs = i;
-
- if (nlimbs >= x->nlimbs) {
- x->nlimbs = 0;
- return;
- }
-
- if (nlimbs) {
- for (i = 0; i < x->nlimbs - nlimbs; i++)
- x->d[i] = x->d[i+nlimbs];
- x->d[i] = 0;
- x->nlimbs -= nlimbs;
- }
-
- if (x->nlimbs && nbits)
- mpihelp_rshift(x->d, x->d, x->nlimbs, nbits);
- } else {
- /* Copy and shift by less than bits in a limb. */
- xsize = a->nlimbs;
- x->sign = a->sign;
- RESIZE_IF_NEEDED(x, xsize);
- x->nlimbs = xsize;
-
- if (xsize) {
- if (nbits)
- mpihelp_rshift(x->d, a->d, x->nlimbs, nbits);
- else {
- /* The rshift helper function is not specified for
- * NBITS==0, thus we do a plain copy here.
- */
- for (i = 0; i < x->nlimbs; i++)
- x->d[i] = a->d[i];
- }
- }
- }
- MPN_NORMALIZE(x->d, x->nlimbs);
-}
-EXPORT_SYMBOL_GPL(mpi_rshift);
-
-/****************
- * Shift A by COUNT limbs to the left
- * This is used only within the MPI library
- */
-void mpi_lshift_limbs(MPI a, unsigned int count)
-{
- mpi_ptr_t ap;
- int n = a->nlimbs;
- int i;
-
- if (!count || !n)
- return;
-
- RESIZE_IF_NEEDED(a, n+count);
-
- ap = a->d;
- for (i = n-1; i >= 0; i--)
- ap[i+count] = ap[i];
- for (i = 0; i < count; i++)
- ap[i] = 0;
- a->nlimbs += count;
-}
-
-/*
- * Shift A by N bits to the left.
- */
-void mpi_lshift(MPI x, MPI a, unsigned int n)
-{
- unsigned int nlimbs = (n/BITS_PER_MPI_LIMB);
- unsigned int nbits = (n%BITS_PER_MPI_LIMB);
-
- if (x == a && !n)
- return; /* In-place shift with an amount of zero. */
-
- if (x != a) {
- /* Copy A to X. */
- unsigned int alimbs = a->nlimbs;
- int asign = a->sign;
- mpi_ptr_t xp, ap;
-
- RESIZE_IF_NEEDED(x, alimbs+nlimbs+1);
- xp = x->d;
- ap = a->d;
- MPN_COPY(xp, ap, alimbs);
- x->nlimbs = alimbs;
- x->flags = a->flags;
- x->sign = asign;
- }
-
- if (nlimbs && !nbits) {
- /* Shift a full number of limbs. */
- mpi_lshift_limbs(x, nlimbs);
- } else if (n) {
- /* We use a very dump approach: Shift left by the number of
- * limbs plus one and than fix it up by an rshift.
- */
- mpi_lshift_limbs(x, nlimbs+1);
- mpi_rshift(x, x, BITS_PER_MPI_LIMB - nbits);
- }
-
- MPN_NORMALIZE(x->d, x->nlimbs);
-}