Adding upstream version 5.10.209.upstream/5.10.209upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 330 insertions, 0 deletions

diff --git a/lib/mpi/mpiutil.c b/lib/mpi/mpiutil.c
new file mode 100644
index 000000000..e6c4b3180
--- /dev/null
+++ b/lib/mpi/mpiutil.c
@@ -0,0 +1,330 @@
+/* mpiutil.ac  -  Utility functions for MPI
+ * 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"
+
+/* Constants allocated right away at startup.  */
+static MPI constants[MPI_NUMBER_OF_CONSTANTS];
+
+/* Initialize the MPI subsystem.  This is called early and allows to
+ * do some initialization without taking care of threading issues.
+ */
+static int __init mpi_init(void)
+{
+	int idx;
+	unsigned long value;
+
+	for (idx = 0; idx < MPI_NUMBER_OF_CONSTANTS; idx++) {
+		switch (idx) {
+		case MPI_C_ZERO:
+			value = 0;
+			break;
+		case MPI_C_ONE:
+			value = 1;
+			break;
+		case MPI_C_TWO:
+			value = 2;
+			break;
+		case MPI_C_THREE:
+			value = 3;
+			break;
+		case MPI_C_FOUR:
+			value = 4;
+			break;
+		case MPI_C_EIGHT:
+			value = 8;
+			break;
+		default:
+			pr_err("MPI: invalid mpi_const selector %d\n", idx);
+			return -EFAULT;
+		}
+		constants[idx] = mpi_alloc_set_ui(value);
+		constants[idx]->flags = (16|32);
+	}
+
+	return 0;
+}
+postcore_initcall(mpi_init);
+
+/* Return a constant MPI descripbed by NO which is one of the
+ * MPI_C_xxx macros.  There is no need to copy this returned value; it
+ * may be used directly.
+ */
+MPI mpi_const(enum gcry_mpi_constants no)
+{
+	if ((int)no < 0 || no > MPI_NUMBER_OF_CONSTANTS)
+		pr_err("MPI: invalid mpi_const selector %d\n", no);
+	if (!constants[no])
+		pr_err("MPI: MPI subsystem not initialized\n");
+	return constants[no];
+}
+EXPORT_SYMBOL_GPL(mpi_const);
+
+/****************
+ * Note:  It was a bad idea to use the number of limbs to allocate
+ *	  because on a alpha the limbs are large but we normally need
+ *	  integers of n bits - So we should chnage this to bits (or bytes).
+ *
+ *	  But mpi_alloc is used in a lot of places :-)
+ */
+MPI mpi_alloc(unsigned nlimbs)
+{
+	MPI a;
+
+	a = kmalloc(sizeof *a, GFP_KERNEL);
+	if (!a)
+		return a;
+
+	if (nlimbs) {
+		a->d = mpi_alloc_limb_space(nlimbs);
+		if (!a->d) {
+			kfree(a);
+			return NULL;
+		}
+	} else {
+		a->d = NULL;
+	}
+
+	a->alloced = nlimbs;
+	a->nlimbs = 0;
+	a->sign = 0;
+	a->flags = 0;
+	a->nbits = 0;
+	return a;
+}
+EXPORT_SYMBOL_GPL(mpi_alloc);
+
+mpi_ptr_t mpi_alloc_limb_space(unsigned nlimbs)
+{
+	size_t len = nlimbs * sizeof(mpi_limb_t);
+
+	if (!len)
+		return NULL;
+
+	return kmalloc(len, GFP_KERNEL);
+}
+
+void mpi_free_limb_space(mpi_ptr_t a)
+{
+	if (!a)
+		return;
+
+	kfree_sensitive(a);
+}
+
+void mpi_assign_limb_space(MPI a, mpi_ptr_t ap, unsigned nlimbs)
+{
+	mpi_free_limb_space(a->d);
+	a->d = ap;
+	a->alloced = nlimbs;
+}
+
+/****************
+ * Resize the array of A to NLIMBS. the additional space is cleared
+ * (set to 0) [done by m_realloc()]
+ */
+int mpi_resize(MPI a, unsigned nlimbs)
+{
+	void *p;
+
+	if (nlimbs <= a->alloced)
+		return 0;	/* no need to do it */
+
+	if (a->d) {
+		p = kcalloc(nlimbs, sizeof(mpi_limb_t), GFP_KERNEL);
+		if (!p)
+			return -ENOMEM;
+		memcpy(p, a->d, a->alloced * sizeof(mpi_limb_t));
+		kfree_sensitive(a->d);
+		a->d = p;
+	} else {
+		a->d = kcalloc(nlimbs, sizeof(mpi_limb_t), GFP_KERNEL);
+		if (!a->d)
+			return -ENOMEM;
+	}
+	a->alloced = nlimbs;
+	return 0;
+}
+
+void mpi_clear(MPI a)
+{
+	if (!a)
+		return;
+	a->nlimbs = 0;
+	a->flags = 0;
+}
+EXPORT_SYMBOL_GPL(mpi_clear);
+
+void mpi_free(MPI a)
+{
+	if (!a)
+		return;
+
+	if (a->flags & 4)
+		kfree_sensitive(a->d);
+	else
+		mpi_free_limb_space(a->d);
+
+	if (a->flags & ~7)
+		pr_info("invalid flag value in mpi\n");
+	kfree(a);
+}
+EXPORT_SYMBOL_GPL(mpi_free);
+
+/****************
+ * Note: This copy function should not interpret the MPI
+ *	 but copy it transparently.
+ */
+MPI mpi_copy(MPI a)
+{
+	int i;
+	MPI b;
+
+	if (a) {
+		b = mpi_alloc(a->nlimbs);
+		b->nlimbs = a->nlimbs;
+		b->sign = a->sign;
+		b->flags = a->flags;
+		b->flags &= ~(16|32); /* Reset the immutable and constant flags. */
+		for (i = 0; i < b->nlimbs; i++)
+			b->d[i] = a->d[i];
+	} else
+		b = NULL;
+	return b;
+}
+
+/****************
+ * This function allocates an MPI which is optimized to hold
+ * a value as large as the one given in the argument and allocates it
+ * with the same flags as A.
+ */
+MPI mpi_alloc_like(MPI a)
+{
+	MPI b;
+
+	if (a) {
+		b = mpi_alloc(a->nlimbs);
+		b->nlimbs = 0;
+		b->sign = 0;
+		b->flags = a->flags;
+	} else
+		b = NULL;
+
+	return b;
+}
+
+
+/* Set U into W and release U.  If W is NULL only U will be released. */
+void mpi_snatch(MPI w, MPI u)
+{
+	if (w) {
+		mpi_assign_limb_space(w, u->d, u->alloced);
+		w->nlimbs = u->nlimbs;
+		w->sign   = u->sign;
+		w->flags  = u->flags;
+		u->alloced = 0;
+		u->nlimbs = 0;
+		u->d = NULL;
+	}
+	mpi_free(u);
+}
+
+
+MPI mpi_set(MPI w, MPI u)
+{
+	mpi_ptr_t wp, up;
+	mpi_size_t usize = u->nlimbs;
+	int usign = u->sign;
+
+	if (!w)
+		w = mpi_alloc(mpi_get_nlimbs(u));
+	RESIZE_IF_NEEDED(w, usize);
+	wp = w->d;
+	up = u->d;
+	MPN_COPY(wp, up, usize);
+	w->nlimbs = usize;
+	w->flags = u->flags;
+	w->flags &= ~(16|32); /* Reset the immutable and constant flags.  */
+	w->sign = usign;
+	return w;
+}
+EXPORT_SYMBOL_GPL(mpi_set);
+
+MPI mpi_set_ui(MPI w, unsigned long u)
+{
+	if (!w)
+		w = mpi_alloc(1);
+	/* FIXME: If U is 0 we have no need to resize and thus possible
+	 * allocating the the limbs.
+	 */
+	RESIZE_IF_NEEDED(w, 1);
+	w->d[0] = u;
+	w->nlimbs = u ? 1 : 0;
+	w->sign = 0;
+	w->flags = 0;
+	return w;
+}
+EXPORT_SYMBOL_GPL(mpi_set_ui);
+
+MPI mpi_alloc_set_ui(unsigned long u)
+{
+	MPI w = mpi_alloc(1);
+	w->d[0] = u;
+	w->nlimbs = u ? 1 : 0;
+	w->sign = 0;
+	return w;
+}
+
+/****************
+ * Swap the value of A and B, when SWAP is 1.
+ * Leave the value when SWAP is 0.
+ * This implementation should be constant-time regardless of SWAP.
+ */
+void mpi_swap_cond(MPI a, MPI b, unsigned long swap)
+{
+	mpi_size_t i;
+	mpi_size_t nlimbs;
+	mpi_limb_t mask = ((mpi_limb_t)0) - swap;
+	mpi_limb_t x;
+
+	if (a->alloced > b->alloced)
+		nlimbs = b->alloced;
+	else
+		nlimbs = a->alloced;
+	if (a->nlimbs > nlimbs || b->nlimbs > nlimbs)
+		return;
+
+	for (i = 0; i < nlimbs; i++) {
+		x = mask & (a->d[i] ^ b->d[i]);
+		a->d[i] = a->d[i] ^ x;
+		b->d[i] = b->d[i] ^ x;
+	}
+
+	x = mask & (a->nlimbs ^ b->nlimbs);
+	a->nlimbs = a->nlimbs ^ x;
+	b->nlimbs = b->nlimbs ^ x;
+
+	x = mask & (a->sign ^ b->sign);
+	a->sign = a->sign ^ x;
+	b->sign = b->sign ^ x;
+}
+
+MODULE_DESCRIPTION("Multiprecision maths library");
+MODULE_LICENSE("GPL");