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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /lib/mpi
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'lib/mpi')
-rw-r--r--lib/mpi/Makefile30
-rw-r--r--lib/mpi/ec.c1506
-rw-r--r--lib/mpi/generic_mpih-add1.c48
-rw-r--r--lib/mpi/generic_mpih-lshift.c50
-rw-r--r--lib/mpi/generic_mpih-mul1.c44
-rw-r--r--lib/mpi/generic_mpih-mul2.c47
-rw-r--r--lib/mpi/generic_mpih-mul3.c48
-rw-r--r--lib/mpi/generic_mpih-rshift.c50
-rw-r--r--lib/mpi/generic_mpih-sub1.c47
-rw-r--r--lib/mpi/longlong.h1361
-rw-r--r--lib/mpi/mpi-add.c155
-rw-r--r--lib/mpi/mpi-bit.c308
-rw-r--r--lib/mpi/mpi-cmp.c98
-rw-r--r--lib/mpi/mpi-div.c234
-rw-r--r--lib/mpi/mpi-inline.h109
-rw-r--r--lib/mpi/mpi-internal.h232
-rw-r--r--lib/mpi/mpi-inv.c143
-rw-r--r--lib/mpi/mpi-mod.c157
-rw-r--r--lib/mpi/mpi-mul.c92
-rw-r--r--lib/mpi/mpi-pow.c314
-rw-r--r--lib/mpi/mpi-sub-ui.c78
-rw-r--r--lib/mpi/mpicoder.c752
-rw-r--r--lib/mpi/mpih-cmp.c43
-rw-r--r--lib/mpi/mpih-div.c517
-rw-r--r--lib/mpi/mpih-mul.c509
-rw-r--r--lib/mpi/mpiutil.c330
26 files changed, 7302 insertions, 0 deletions
diff --git a/lib/mpi/Makefile b/lib/mpi/Makefile
new file mode 100644
index 000000000..6e6ef9a34
--- /dev/null
+++ b/lib/mpi/Makefile
@@ -0,0 +1,30 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# MPI multiprecision maths library (from gpg)
+#
+
+obj-$(CONFIG_MPILIB) = mpi.o
+
+mpi-y = \
+ generic_mpih-lshift.o \
+ generic_mpih-mul1.o \
+ generic_mpih-mul2.o \
+ generic_mpih-mul3.o \
+ generic_mpih-rshift.o \
+ generic_mpih-sub1.o \
+ generic_mpih-add1.o \
+ ec.o \
+ mpicoder.o \
+ mpi-add.o \
+ mpi-bit.o \
+ mpi-cmp.o \
+ mpi-sub-ui.o \
+ mpi-div.o \
+ mpi-inv.o \
+ mpi-mod.o \
+ mpi-mul.o \
+ mpih-cmp.o \
+ mpih-div.o \
+ mpih-mul.o \
+ mpi-pow.o \
+ mpiutil.o
diff --git a/lib/mpi/ec.c b/lib/mpi/ec.c
new file mode 100644
index 000000000..40f5908e5
--- /dev/null
+++ b/lib/mpi/ec.c
@@ -0,0 +1,1506 @@
+/* ec.c - Elliptic Curve functions
+ * Copyright (C) 2007 Free Software Foundation, Inc.
+ * Copyright (C) 2013 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 <http://www.gnu.org/licenses/>.
+ */
+
+#include "mpi-internal.h"
+#include "longlong.h"
+
+#define point_init(a) mpi_point_init((a))
+#define point_free(a) mpi_point_free_parts((a))
+
+#define log_error(fmt, ...) pr_err(fmt, ##__VA_ARGS__)
+#define log_fatal(fmt, ...) pr_err(fmt, ##__VA_ARGS__)
+
+#define DIM(v) (sizeof(v)/sizeof((v)[0]))
+
+
+/* Create a new point option. NBITS gives the size in bits of one
+ * coordinate; it is only used to pre-allocate some resources and
+ * might also be passed as 0 to use a default value.
+ */
+MPI_POINT mpi_point_new(unsigned int nbits)
+{
+ MPI_POINT p;
+
+ (void)nbits; /* Currently not used. */
+
+ p = kmalloc(sizeof(*p), GFP_KERNEL);
+ if (p)
+ mpi_point_init(p);
+ return p;
+}
+EXPORT_SYMBOL_GPL(mpi_point_new);
+
+/* Release the point object P. P may be NULL. */
+void mpi_point_release(MPI_POINT p)
+{
+ if (p) {
+ mpi_point_free_parts(p);
+ kfree(p);
+ }
+}
+EXPORT_SYMBOL_GPL(mpi_point_release);
+
+/* Initialize the fields of a point object. gcry_mpi_point_free_parts
+ * may be used to release the fields.
+ */
+void mpi_point_init(MPI_POINT p)
+{
+ p->x = mpi_new(0);
+ p->y = mpi_new(0);
+ p->z = mpi_new(0);
+}
+EXPORT_SYMBOL_GPL(mpi_point_init);
+
+/* Release the parts of a point object. */
+void mpi_point_free_parts(MPI_POINT p)
+{
+ mpi_free(p->x); p->x = NULL;
+ mpi_free(p->y); p->y = NULL;
+ mpi_free(p->z); p->z = NULL;
+}
+EXPORT_SYMBOL_GPL(mpi_point_free_parts);
+
+/* Set the value from S into D. */
+static void point_set(MPI_POINT d, MPI_POINT s)
+{
+ mpi_set(d->x, s->x);
+ mpi_set(d->y, s->y);
+ mpi_set(d->z, s->z);
+}
+
+static void point_resize(MPI_POINT p, struct mpi_ec_ctx *ctx)
+{
+ size_t nlimbs = ctx->p->nlimbs;
+
+ mpi_resize(p->x, nlimbs);
+ p->x->nlimbs = nlimbs;
+ mpi_resize(p->z, nlimbs);
+ p->z->nlimbs = nlimbs;
+
+ if (ctx->model != MPI_EC_MONTGOMERY) {
+ mpi_resize(p->y, nlimbs);
+ p->y->nlimbs = nlimbs;
+ }
+}
+
+static void point_swap_cond(MPI_POINT d, MPI_POINT s, unsigned long swap,
+ struct mpi_ec_ctx *ctx)
+{
+ mpi_swap_cond(d->x, s->x, swap);
+ if (ctx->model != MPI_EC_MONTGOMERY)
+ mpi_swap_cond(d->y, s->y, swap);
+ mpi_swap_cond(d->z, s->z, swap);
+}
+
+
+/* W = W mod P. */
+static void ec_mod(MPI w, struct mpi_ec_ctx *ec)
+{
+ if (ec->t.p_barrett)
+ mpi_mod_barrett(w, w, ec->t.p_barrett);
+ else
+ mpi_mod(w, w, ec->p);
+}
+
+static void ec_addm(MPI w, MPI u, MPI v, struct mpi_ec_ctx *ctx)
+{
+ mpi_add(w, u, v);
+ ec_mod(w, ctx);
+}
+
+static void ec_subm(MPI w, MPI u, MPI v, struct mpi_ec_ctx *ec)
+{
+ mpi_sub(w, u, v);
+ while (w->sign)
+ mpi_add(w, w, ec->p);
+ /*ec_mod(w, ec);*/
+}
+
+static void ec_mulm(MPI w, MPI u, MPI v, struct mpi_ec_ctx *ctx)
+{
+ mpi_mul(w, u, v);
+ ec_mod(w, ctx);
+}
+
+/* W = 2 * U mod P. */
+static void ec_mul2(MPI w, MPI u, struct mpi_ec_ctx *ctx)
+{
+ mpi_lshift(w, u, 1);
+ ec_mod(w, ctx);
+}
+
+static void ec_powm(MPI w, const MPI b, const MPI e,
+ struct mpi_ec_ctx *ctx)
+{
+ mpi_powm(w, b, e, ctx->p);
+ /* mpi_abs(w); */
+}
+
+/* Shortcut for
+ * ec_powm(B, B, mpi_const(MPI_C_TWO), ctx);
+ * for easier optimization.
+ */
+static void ec_pow2(MPI w, const MPI b, struct mpi_ec_ctx *ctx)
+{
+ /* Using mpi_mul is slightly faster (at least on amd64). */
+ /* mpi_powm(w, b, mpi_const(MPI_C_TWO), ctx->p); */
+ ec_mulm(w, b, b, ctx);
+}
+
+/* Shortcut for
+ * ec_powm(B, B, mpi_const(MPI_C_THREE), ctx);
+ * for easier optimization.
+ */
+static void ec_pow3(MPI w, const MPI b, struct mpi_ec_ctx *ctx)
+{
+ mpi_powm(w, b, mpi_const(MPI_C_THREE), ctx->p);
+}
+
+static void ec_invm(MPI x, MPI a, struct mpi_ec_ctx *ctx)
+{
+ if (!mpi_invm(x, a, ctx->p))
+ log_error("ec_invm: inverse does not exist:\n");
+}
+
+static void mpih_set_cond(mpi_ptr_t wp, mpi_ptr_t up,
+ mpi_size_t usize, unsigned long set)
+{
+ mpi_size_t i;
+ mpi_limb_t mask = ((mpi_limb_t)0) - set;
+ mpi_limb_t x;
+
+ for (i = 0; i < usize; i++) {
+ x = mask & (wp[i] ^ up[i]);
+ wp[i] = wp[i] ^ x;
+ }
+}
+
+/* Routines for 2^255 - 19. */
+
+#define LIMB_SIZE_25519 ((256+BITS_PER_MPI_LIMB-1)/BITS_PER_MPI_LIMB)
+
+static void ec_addm_25519(MPI w, MPI u, MPI v, struct mpi_ec_ctx *ctx)
+{
+ mpi_ptr_t wp, up, vp;
+ mpi_size_t wsize = LIMB_SIZE_25519;
+ mpi_limb_t n[LIMB_SIZE_25519];
+ mpi_limb_t borrow;
+
+ if (w->nlimbs != wsize || u->nlimbs != wsize || v->nlimbs != wsize)
+ log_bug("addm_25519: different sizes\n");
+
+ memset(n, 0, sizeof(n));
+ up = u->d;
+ vp = v->d;
+ wp = w->d;
+
+ mpihelp_add_n(wp, up, vp, wsize);
+ borrow = mpihelp_sub_n(wp, wp, ctx->p->d, wsize);
+ mpih_set_cond(n, ctx->p->d, wsize, (borrow != 0UL));
+ mpihelp_add_n(wp, wp, n, wsize);
+ wp[LIMB_SIZE_25519-1] &= ~((mpi_limb_t)1 << (255 % BITS_PER_MPI_LIMB));
+}
+
+static void ec_subm_25519(MPI w, MPI u, MPI v, struct mpi_ec_ctx *ctx)
+{
+ mpi_ptr_t wp, up, vp;
+ mpi_size_t wsize = LIMB_SIZE_25519;
+ mpi_limb_t n[LIMB_SIZE_25519];
+ mpi_limb_t borrow;
+
+ if (w->nlimbs != wsize || u->nlimbs != wsize || v->nlimbs != wsize)
+ log_bug("subm_25519: different sizes\n");
+
+ memset(n, 0, sizeof(n));
+ up = u->d;
+ vp = v->d;
+ wp = w->d;
+
+ borrow = mpihelp_sub_n(wp, up, vp, wsize);
+ mpih_set_cond(n, ctx->p->d, wsize, (borrow != 0UL));
+ mpihelp_add_n(wp, wp, n, wsize);
+ wp[LIMB_SIZE_25519-1] &= ~((mpi_limb_t)1 << (255 % BITS_PER_MPI_LIMB));
+}
+
+static void ec_mulm_25519(MPI w, MPI u, MPI v, struct mpi_ec_ctx *ctx)
+{
+ mpi_ptr_t wp, up, vp;
+ mpi_size_t wsize = LIMB_SIZE_25519;
+ mpi_limb_t n[LIMB_SIZE_25519*2];
+ mpi_limb_t m[LIMB_SIZE_25519+1];
+ mpi_limb_t cy;
+ int msb;
+
+ (void)ctx;
+ if (w->nlimbs != wsize || u->nlimbs != wsize || v->nlimbs != wsize)
+ log_bug("mulm_25519: different sizes\n");
+
+ up = u->d;
+ vp = v->d;
+ wp = w->d;
+
+ mpihelp_mul_n(n, up, vp, wsize);
+ memcpy(wp, n, wsize * BYTES_PER_MPI_LIMB);
+ wp[LIMB_SIZE_25519-1] &= ~((mpi_limb_t)1 << (255 % BITS_PER_MPI_LIMB));
+
+ memcpy(m, n+LIMB_SIZE_25519-1, (wsize+1) * BYTES_PER_MPI_LIMB);
+ mpihelp_rshift(m, m, LIMB_SIZE_25519+1, (255 % BITS_PER_MPI_LIMB));
+
+ memcpy(n, m, wsize * BYTES_PER_MPI_LIMB);
+ cy = mpihelp_lshift(m, m, LIMB_SIZE_25519, 4);
+ m[LIMB_SIZE_25519] = cy;
+ cy = mpihelp_add_n(m, m, n, wsize);
+ m[LIMB_SIZE_25519] += cy;
+ cy = mpihelp_add_n(m, m, n, wsize);
+ m[LIMB_SIZE_25519] += cy;
+ cy = mpihelp_add_n(m, m, n, wsize);
+ m[LIMB_SIZE_25519] += cy;
+
+ cy = mpihelp_add_n(wp, wp, m, wsize);
+ m[LIMB_SIZE_25519] += cy;
+
+ memset(m, 0, wsize * BYTES_PER_MPI_LIMB);
+ msb = (wp[LIMB_SIZE_25519-1] >> (255 % BITS_PER_MPI_LIMB));
+ m[0] = (m[LIMB_SIZE_25519] * 2 + msb) * 19;
+ wp[LIMB_SIZE_25519-1] &= ~((mpi_limb_t)1 << (255 % BITS_PER_MPI_LIMB));
+ mpihelp_add_n(wp, wp, m, wsize);
+
+ m[0] = 0;
+ cy = mpihelp_sub_n(wp, wp, ctx->p->d, wsize);
+ mpih_set_cond(m, ctx->p->d, wsize, (cy != 0UL));
+ mpihelp_add_n(wp, wp, m, wsize);
+}
+
+static void ec_mul2_25519(MPI w, MPI u, struct mpi_ec_ctx *ctx)
+{
+ ec_addm_25519(w, u, u, ctx);
+}
+
+static void ec_pow2_25519(MPI w, const MPI b, struct mpi_ec_ctx *ctx)
+{
+ ec_mulm_25519(w, b, b, ctx);
+}
+
+/* Routines for 2^448 - 2^224 - 1. */
+
+#define LIMB_SIZE_448 ((448+BITS_PER_MPI_LIMB-1)/BITS_PER_MPI_LIMB)
+#define LIMB_SIZE_HALF_448 ((LIMB_SIZE_448+1)/2)
+
+static void ec_addm_448(MPI w, MPI u, MPI v, struct mpi_ec_ctx *ctx)
+{
+ mpi_ptr_t wp, up, vp;
+ mpi_size_t wsize = LIMB_SIZE_448;
+ mpi_limb_t n[LIMB_SIZE_448];
+ mpi_limb_t cy;
+
+ if (w->nlimbs != wsize || u->nlimbs != wsize || v->nlimbs != wsize)
+ log_bug("addm_448: different sizes\n");
+
+ memset(n, 0, sizeof(n));
+ up = u->d;
+ vp = v->d;
+ wp = w->d;
+
+ cy = mpihelp_add_n(wp, up, vp, wsize);
+ mpih_set_cond(n, ctx->p->d, wsize, (cy != 0UL));
+ mpihelp_sub_n(wp, wp, n, wsize);
+}
+
+static void ec_subm_448(MPI w, MPI u, MPI v, struct mpi_ec_ctx *ctx)
+{
+ mpi_ptr_t wp, up, vp;
+ mpi_size_t wsize = LIMB_SIZE_448;
+ mpi_limb_t n[LIMB_SIZE_448];
+ mpi_limb_t borrow;
+
+ if (w->nlimbs != wsize || u->nlimbs != wsize || v->nlimbs != wsize)
+ log_bug("subm_448: different sizes\n");
+
+ memset(n, 0, sizeof(n));
+ up = u->d;
+ vp = v->d;
+ wp = w->d;
+
+ borrow = mpihelp_sub_n(wp, up, vp, wsize);
+ mpih_set_cond(n, ctx->p->d, wsize, (borrow != 0UL));
+ mpihelp_add_n(wp, wp, n, wsize);
+}
+
+static void ec_mulm_448(MPI w, MPI u, MPI v, struct mpi_ec_ctx *ctx)
+{
+ mpi_ptr_t wp, up, vp;
+ mpi_size_t wsize = LIMB_SIZE_448;
+ mpi_limb_t n[LIMB_SIZE_448*2];
+ mpi_limb_t a2[LIMB_SIZE_HALF_448];
+ mpi_limb_t a3[LIMB_SIZE_HALF_448];
+ mpi_limb_t b0[LIMB_SIZE_HALF_448];
+ mpi_limb_t b1[LIMB_SIZE_HALF_448];
+ mpi_limb_t cy;
+ int i;
+#if (LIMB_SIZE_HALF_448 > LIMB_SIZE_448/2)
+ mpi_limb_t b1_rest, a3_rest;
+#endif
+
+ if (w->nlimbs != wsize || u->nlimbs != wsize || v->nlimbs != wsize)
+ log_bug("mulm_448: different sizes\n");
+
+ up = u->d;
+ vp = v->d;
+ wp = w->d;
+
+ mpihelp_mul_n(n, up, vp, wsize);
+
+ for (i = 0; i < (wsize + 1) / 2; i++) {
+ b0[i] = n[i];
+ b1[i] = n[i+wsize/2];
+ a2[i] = n[i+wsize];
+ a3[i] = n[i+wsize+wsize/2];
+ }
+
+#if (LIMB_SIZE_HALF_448 > LIMB_SIZE_448/2)
+ b0[LIMB_SIZE_HALF_448-1] &= ((mpi_limb_t)1UL << 32)-1;
+ a2[LIMB_SIZE_HALF_448-1] &= ((mpi_limb_t)1UL << 32)-1;
+
+ b1_rest = 0;
+ a3_rest = 0;
+
+ for (i = (wsize + 1) / 2 - 1; i >= 0; i--) {
+ mpi_limb_t b1v, a3v;
+ b1v = b1[i];
+ a3v = a3[i];
+ b1[i] = (b1_rest << 32) | (b1v >> 32);
+ a3[i] = (a3_rest << 32) | (a3v >> 32);
+ b1_rest = b1v & (((mpi_limb_t)1UL << 32)-1);
+ a3_rest = a3v & (((mpi_limb_t)1UL << 32)-1);
+ }
+#endif
+
+ cy = mpihelp_add_n(b0, b0, a2, LIMB_SIZE_HALF_448);
+ cy += mpihelp_add_n(b0, b0, a3, LIMB_SIZE_HALF_448);
+ for (i = 0; i < (wsize + 1) / 2; i++)
+ wp[i] = b0[i];
+#if (LIMB_SIZE_HALF_448 > LIMB_SIZE_448/2)
+ wp[LIMB_SIZE_HALF_448-1] &= (((mpi_limb_t)1UL << 32)-1);
+#endif
+
+#if (LIMB_SIZE_HALF_448 > LIMB_SIZE_448/2)
+ cy = b0[LIMB_SIZE_HALF_448-1] >> 32;
+#endif
+
+ cy = mpihelp_add_1(b1, b1, LIMB_SIZE_HALF_448, cy);
+ cy += mpihelp_add_n(b1, b1, a2, LIMB_SIZE_HALF_448);
+ cy += mpihelp_add_n(b1, b1, a3, LIMB_SIZE_HALF_448);
+ cy += mpihelp_add_n(b1, b1, a3, LIMB_SIZE_HALF_448);
+#if (LIMB_SIZE_HALF_448 > LIMB_SIZE_448/2)
+ b1_rest = 0;
+ for (i = (wsize + 1) / 2 - 1; i >= 0; i--) {
+ mpi_limb_t b1v = b1[i];
+ b1[i] = (b1_rest << 32) | (b1v >> 32);
+ b1_rest = b1v & (((mpi_limb_t)1UL << 32)-1);
+ }
+ wp[LIMB_SIZE_HALF_448-1] |= (b1_rest << 32);
+#endif
+ for (i = 0; i < wsize / 2; i++)
+ wp[i+(wsize + 1) / 2] = b1[i];
+
+#if (LIMB_SIZE_HALF_448 > LIMB_SIZE_448/2)
+ cy = b1[LIMB_SIZE_HALF_448-1];
+#endif
+
+ memset(n, 0, wsize * BYTES_PER_MPI_LIMB);
+
+#if (LIMB_SIZE_HALF_448 > LIMB_SIZE_448/2)
+ n[LIMB_SIZE_HALF_448-1] = cy << 32;
+#else
+ n[LIMB_SIZE_HALF_448] = cy;
+#endif
+ n[0] = cy;
+ mpihelp_add_n(wp, wp, n, wsize);
+
+ memset(n, 0, wsize * BYTES_PER_MPI_LIMB);
+ cy = mpihelp_sub_n(wp, wp, ctx->p->d, wsize);
+ mpih_set_cond(n, ctx->p->d, wsize, (cy != 0UL));
+ mpihelp_add_n(wp, wp, n, wsize);
+}
+
+static void ec_mul2_448(MPI w, MPI u, struct mpi_ec_ctx *ctx)
+{
+ ec_addm_448(w, u, u, ctx);
+}
+
+static void ec_pow2_448(MPI w, const MPI b, struct mpi_ec_ctx *ctx)
+{
+ ec_mulm_448(w, b, b, ctx);
+}
+
+struct field_table {
+ const char *p;
+
+ /* computation routines for the field. */
+ void (*addm)(MPI w, MPI u, MPI v, struct mpi_ec_ctx *ctx);
+ void (*subm)(MPI w, MPI u, MPI v, struct mpi_ec_ctx *ctx);
+ void (*mulm)(MPI w, MPI u, MPI v, struct mpi_ec_ctx *ctx);
+ void (*mul2)(MPI w, MPI u, struct mpi_ec_ctx *ctx);
+ void (*pow2)(MPI w, const MPI b, struct mpi_ec_ctx *ctx);
+};
+
+static const struct field_table field_table[] = {
+ {
+ "0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFED",
+ ec_addm_25519,
+ ec_subm_25519,
+ ec_mulm_25519,
+ ec_mul2_25519,
+ ec_pow2_25519
+ },
+ {
+ "0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFE"
+ "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF",
+ ec_addm_448,
+ ec_subm_448,
+ ec_mulm_448,
+ ec_mul2_448,
+ ec_pow2_448
+ },
+ { NULL, NULL, NULL, NULL, NULL, NULL },
+};
+
+/* Force recomputation of all helper variables. */
+static void mpi_ec_get_reset(struct mpi_ec_ctx *ec)
+{
+ ec->t.valid.a_is_pminus3 = 0;
+ ec->t.valid.two_inv_p = 0;
+}
+
+/* Accessor for helper variable. */
+static int ec_get_a_is_pminus3(struct mpi_ec_ctx *ec)
+{
+ MPI tmp;
+
+ if (!ec->t.valid.a_is_pminus3) {
+ ec->t.valid.a_is_pminus3 = 1;
+ tmp = mpi_alloc_like(ec->p);
+ mpi_sub_ui(tmp, ec->p, 3);
+ ec->t.a_is_pminus3 = !mpi_cmp(ec->a, tmp);
+ mpi_free(tmp);
+ }
+
+ return ec->t.a_is_pminus3;
+}
+
+/* Accessor for helper variable. */
+static MPI ec_get_two_inv_p(struct mpi_ec_ctx *ec)
+{
+ if (!ec->t.valid.two_inv_p) {
+ ec->t.valid.two_inv_p = 1;
+ if (!ec->t.two_inv_p)
+ ec->t.two_inv_p = mpi_alloc(0);
+ ec_invm(ec->t.two_inv_p, mpi_const(MPI_C_TWO), ec);
+ }
+ return ec->t.two_inv_p;
+}
+
+static const char *const curve25519_bad_points[] = {
+ "0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffed",
+ "0x0000000000000000000000000000000000000000000000000000000000000000",
+ "0x0000000000000000000000000000000000000000000000000000000000000001",
+ "0x00b8495f16056286fdb1329ceb8d09da6ac49ff1fae35616aeb8413b7c7aebe0",
+ "0x57119fd0dd4e22d8868e1c58c45c44045bef839c55b1d0b1248c50a3bc959c5f",
+ "0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffec",
+ "0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffee",
+ NULL
+};
+
+static const char *const curve448_bad_points[] = {
+ "0xfffffffffffffffffffffffffffffffffffffffffffffffffffffffe"
+ "ffffffffffffffffffffffffffffffffffffffffffffffffffffffff",
+ "0x00000000000000000000000000000000000000000000000000000000"
+ "00000000000000000000000000000000000000000000000000000000",
+ "0x00000000000000000000000000000000000000000000000000000000"
+ "00000000000000000000000000000000000000000000000000000001",
+ "0xfffffffffffffffffffffffffffffffffffffffffffffffffffffffe"
+ "fffffffffffffffffffffffffffffffffffffffffffffffffffffffe",
+ "0xffffffffffffffffffffffffffffffffffffffffffffffffffffffff"
+ "00000000000000000000000000000000000000000000000000000000",
+ NULL
+};
+
+static const char *const *bad_points_table[] = {
+ curve25519_bad_points,
+ curve448_bad_points,
+};
+
+static void mpi_ec_coefficient_normalize(MPI a, MPI p)
+{
+ if (a->sign) {
+ mpi_resize(a, p->nlimbs);
+ mpihelp_sub_n(a->d, p->d, a->d, p->nlimbs);
+ a->nlimbs = p->nlimbs;
+ a->sign = 0;
+ }
+}
+
+/* This function initialized a context for elliptic curve based on the
+ * field GF(p). P is the prime specifying this field, A is the first
+ * coefficient. CTX is expected to be zeroized.
+ */
+void mpi_ec_init(struct mpi_ec_ctx *ctx, enum gcry_mpi_ec_models model,
+ enum ecc_dialects dialect,
+ int flags, MPI p, MPI a, MPI b)
+{
+ int i;
+ static int use_barrett = -1 /* TODO: 1 or -1 */;
+
+ mpi_ec_coefficient_normalize(a, p);
+ mpi_ec_coefficient_normalize(b, p);
+
+ /* Fixme: Do we want to check some constraints? e.g. a < p */
+
+ ctx->model = model;
+ ctx->dialect = dialect;
+ ctx->flags = flags;
+ if (dialect == ECC_DIALECT_ED25519)
+ ctx->nbits = 256;
+ else
+ ctx->nbits = mpi_get_nbits(p);
+ ctx->p = mpi_copy(p);
+ ctx->a = mpi_copy(a);
+ ctx->b = mpi_copy(b);
+
+ ctx->t.p_barrett = use_barrett > 0 ? mpi_barrett_init(ctx->p, 0) : NULL;
+
+ mpi_ec_get_reset(ctx);
+
+ if (model == MPI_EC_MONTGOMERY) {
+ for (i = 0; i < DIM(bad_points_table); i++) {
+ MPI p_candidate = mpi_scanval(bad_points_table[i][0]);
+ int match_p = !mpi_cmp(ctx->p, p_candidate);
+ int j;
+
+ mpi_free(p_candidate);
+ if (!match_p)
+ continue;
+
+ for (j = 0; i < DIM(ctx->t.scratch) && bad_points_table[i][j]; j++)
+ ctx->t.scratch[j] = mpi_scanval(bad_points_table[i][j]);
+ }
+ } else {
+ /* Allocate scratch variables. */
+ for (i = 0; i < DIM(ctx->t.scratch); i++)
+ ctx->t.scratch[i] = mpi_alloc_like(ctx->p);
+ }
+
+ ctx->addm = ec_addm;
+ ctx->subm = ec_subm;
+ ctx->mulm = ec_mulm;
+ ctx->mul2 = ec_mul2;
+ ctx->pow2 = ec_pow2;
+
+ for (i = 0; field_table[i].p; i++) {
+ MPI f_p;
+
+ f_p = mpi_scanval(field_table[i].p);
+ if (!f_p)
+ break;
+
+ if (!mpi_cmp(p, f_p)) {
+ ctx->addm = field_table[i].addm;
+ ctx->subm = field_table[i].subm;
+ ctx->mulm = field_table[i].mulm;
+ ctx->mul2 = field_table[i].mul2;
+ ctx->pow2 = field_table[i].pow2;
+ mpi_free(f_p);
+
+ mpi_resize(ctx->a, ctx->p->nlimbs);
+ ctx->a->nlimbs = ctx->p->nlimbs;
+
+ mpi_resize(ctx->b, ctx->p->nlimbs);
+ ctx->b->nlimbs = ctx->p->nlimbs;
+
+ for (i = 0; i < DIM(ctx->t.scratch) && ctx->t.scratch[i]; i++)
+ ctx->t.scratch[i]->nlimbs = ctx->p->nlimbs;
+
+ break;
+ }
+
+ mpi_free(f_p);
+ }
+}
+EXPORT_SYMBOL_GPL(mpi_ec_init);
+
+void mpi_ec_deinit(struct mpi_ec_ctx *ctx)
+{
+ int i;
+
+ mpi_barrett_free(ctx->t.p_barrett);
+
+ /* Domain parameter. */
+ mpi_free(ctx->p);
+ mpi_free(ctx->a);
+ mpi_free(ctx->b);
+ mpi_point_release(ctx->G);
+ mpi_free(ctx->n);
+
+ /* The key. */
+ mpi_point_release(ctx->Q);
+ mpi_free(ctx->d);
+
+ /* Private data of ec.c. */
+ mpi_free(ctx->t.two_inv_p);
+
+ for (i = 0; i < DIM(ctx->t.scratch); i++)
+ mpi_free(ctx->t.scratch[i]);
+}
+EXPORT_SYMBOL_GPL(mpi_ec_deinit);
+
+/* Compute the affine coordinates from the projective coordinates in
+ * POINT. Set them into X and Y. If one coordinate is not required,
+ * X or Y may be passed as NULL. CTX is the usual context. Returns: 0
+ * on success or !0 if POINT is at infinity.
+ */
+int mpi_ec_get_affine(MPI x, MPI y, MPI_POINT point, struct mpi_ec_ctx *ctx)
+{
+ if (!mpi_cmp_ui(point->z, 0))
+ return -1;
+
+ switch (ctx->model) {
+ case MPI_EC_WEIERSTRASS: /* Using Jacobian coordinates. */
+ {
+ MPI z1, z2, z3;
+
+ z1 = mpi_new(0);
+ z2 = mpi_new(0);
+ ec_invm(z1, point->z, ctx); /* z1 = z^(-1) mod p */
+ ec_mulm(z2, z1, z1, ctx); /* z2 = z^(-2) mod p */
+
+ if (x)
+ ec_mulm(x, point->x, z2, ctx);
+
+ if (y) {
+ z3 = mpi_new(0);
+ ec_mulm(z3, z2, z1, ctx); /* z3 = z^(-3) mod p */
+ ec_mulm(y, point->y, z3, ctx);
+ mpi_free(z3);
+ }
+
+ mpi_free(z2);
+ mpi_free(z1);
+ }
+ return 0;
+
+ case MPI_EC_MONTGOMERY:
+ {
+ if (x)
+ mpi_set(x, point->x);
+
+ if (y) {
+ log_fatal("%s: Getting Y-coordinate on %s is not supported\n",
+ "mpi_ec_get_affine", "Montgomery");
+ return -1;
+ }
+ }
+ return 0;
+
+ case MPI_EC_EDWARDS:
+ {
+ MPI z;
+
+ z = mpi_new(0);
+ ec_invm(z, point->z, ctx);
+
+ mpi_resize(z, ctx->p->nlimbs);
+ z->nlimbs = ctx->p->nlimbs;
+
+ if (x) {
+ mpi_resize(x, ctx->p->nlimbs);
+ x->nlimbs = ctx->p->nlimbs;
+ ctx->mulm(x, point->x, z, ctx);
+ }
+ if (y) {
+ mpi_resize(y, ctx->p->nlimbs);
+ y->nlimbs = ctx->p->nlimbs;
+ ctx->mulm(y, point->y, z, ctx);
+ }
+
+ mpi_free(z);
+ }
+ return 0;
+
+ default:
+ return -1;
+ }
+}
+EXPORT_SYMBOL_GPL(mpi_ec_get_affine);
+
+/* RESULT = 2 * POINT (Weierstrass version). */
+static void dup_point_weierstrass(MPI_POINT result,
+ MPI_POINT point, struct mpi_ec_ctx *ctx)
+{
+#define x3 (result->x)
+#define y3 (result->y)
+#define z3 (result->z)
+#define t1 (ctx->t.scratch[0])
+#define t2 (ctx->t.scratch[1])
+#define t3 (ctx->t.scratch[2])
+#define l1 (ctx->t.scratch[3])
+#define l2 (ctx->t.scratch[4])
+#define l3 (ctx->t.scratch[5])
+
+ if (!mpi_cmp_ui(point->y, 0) || !mpi_cmp_ui(point->z, 0)) {
+ /* P_y == 0 || P_z == 0 => [1:1:0] */
+ mpi_set_ui(x3, 1);
+ mpi_set_ui(y3, 1);
+ mpi_set_ui(z3, 0);
+ } else {
+ if (ec_get_a_is_pminus3(ctx)) {
+ /* Use the faster case. */
+ /* L1 = 3(X - Z^2)(X + Z^2) */
+ /* T1: used for Z^2. */
+ /* T2: used for the right term. */
+ ec_pow2(t1, point->z, ctx);
+ ec_subm(l1, point->x, t1, ctx);
+ ec_mulm(l1, l1, mpi_const(MPI_C_THREE), ctx);
+ ec_addm(t2, point->x, t1, ctx);
+ ec_mulm(l1, l1, t2, ctx);
+ } else {
+ /* Standard case. */
+ /* L1 = 3X^2 + aZ^4 */
+ /* T1: used for aZ^4. */
+ ec_pow2(l1, point->x, ctx);
+ ec_mulm(l1, l1, mpi_const(MPI_C_THREE), ctx);
+ ec_powm(t1, point->z, mpi_const(MPI_C_FOUR), ctx);
+ ec_mulm(t1, t1, ctx->a, ctx);
+ ec_addm(l1, l1, t1, ctx);
+ }
+ /* Z3 = 2YZ */
+ ec_mulm(z3, point->y, point->z, ctx);
+ ec_mul2(z3, z3, ctx);
+
+ /* L2 = 4XY^2 */
+ /* T2: used for Y2; required later. */
+ ec_pow2(t2, point->y, ctx);
+ ec_mulm(l2, t2, point->x, ctx);
+ ec_mulm(l2, l2, mpi_const(MPI_C_FOUR), ctx);
+
+ /* X3 = L1^2 - 2L2 */
+ /* T1: used for L2^2. */
+ ec_pow2(x3, l1, ctx);
+ ec_mul2(t1, l2, ctx);
+ ec_subm(x3, x3, t1, ctx);
+
+ /* L3 = 8Y^4 */
+ /* T2: taken from above. */
+ ec_pow2(t2, t2, ctx);
+ ec_mulm(l3, t2, mpi_const(MPI_C_EIGHT), ctx);
+
+ /* Y3 = L1(L2 - X3) - L3 */
+ ec_subm(y3, l2, x3, ctx);
+ ec_mulm(y3, y3, l1, ctx);
+ ec_subm(y3, y3, l3, ctx);
+ }
+
+#undef x3
+#undef y3
+#undef z3
+#undef t1
+#undef t2
+#undef t3
+#undef l1
+#undef l2
+#undef l3
+}
+
+/* RESULT = 2 * POINT (Montgomery version). */
+static void dup_point_montgomery(MPI_POINT result,
+ MPI_POINT point, struct mpi_ec_ctx *ctx)
+{
+ (void)result;
+ (void)point;
+ (void)ctx;
+ log_fatal("%s: %s not yet supported\n",
+ "mpi_ec_dup_point", "Montgomery");
+}
+
+/* RESULT = 2 * POINT (Twisted Edwards version). */
+static void dup_point_edwards(MPI_POINT result,
+ MPI_POINT point, struct mpi_ec_ctx *ctx)
+{
+#define X1 (point->x)
+#define Y1 (point->y)
+#define Z1 (point->z)
+#define X3 (result->x)
+#define Y3 (result->y)
+#define Z3 (result->z)
+#define B (ctx->t.scratch[0])
+#define C (ctx->t.scratch[1])
+#define D (ctx->t.scratch[2])
+#define E (ctx->t.scratch[3])
+#define F (ctx->t.scratch[4])
+#define H (ctx->t.scratch[5])
+#define J (ctx->t.scratch[6])
+
+ /* Compute: (X_3 : Y_3 : Z_3) = 2( X_1 : Y_1 : Z_1 ) */
+
+ /* B = (X_1 + Y_1)^2 */
+ ctx->addm(B, X1, Y1, ctx);
+ ctx->pow2(B, B, ctx);
+
+ /* C = X_1^2 */
+ /* D = Y_1^2 */
+ ctx->pow2(C, X1, ctx);
+ ctx->pow2(D, Y1, ctx);
+
+ /* E = aC */
+ if (ctx->dialect == ECC_DIALECT_ED25519)
+ ctx->subm(E, ctx->p, C, ctx);
+ else
+ ctx->mulm(E, ctx->a, C, ctx);
+
+ /* F = E + D */
+ ctx->addm(F, E, D, ctx);
+
+ /* H = Z_1^2 */
+ ctx->pow2(H, Z1, ctx);
+
+ /* J = F - 2H */
+ ctx->mul2(J, H, ctx);
+ ctx->subm(J, F, J, ctx);
+
+ /* X_3 = (B - C - D) · J */
+ ctx->subm(X3, B, C, ctx);
+ ctx->subm(X3, X3, D, ctx);
+ ctx->mulm(X3, X3, J, ctx);
+
+ /* Y_3 = F · (E - D) */
+ ctx->subm(Y3, E, D, ctx);
+ ctx->mulm(Y3, Y3, F, ctx);
+
+ /* Z_3 = F · J */
+ ctx->mulm(Z3, F, J, ctx);
+
+#undef X1
+#undef Y1
+#undef Z1
+#undef X3
+#undef Y3
+#undef Z3
+#undef B
+#undef C
+#undef D
+#undef E
+#undef F
+#undef H
+#undef J
+}
+
+/* RESULT = 2 * POINT */
+static void
+mpi_ec_dup_point(MPI_POINT result, MPI_POINT point, struct mpi_ec_ctx *ctx)
+{
+ switch (ctx->model) {
+ case MPI_EC_WEIERSTRASS:
+ dup_point_weierstrass(result, point, ctx);
+ break;
+ case MPI_EC_MONTGOMERY:
+ dup_point_montgomery(result, point, ctx);
+ break;
+ case MPI_EC_EDWARDS:
+ dup_point_edwards(result, point, ctx);
+ break;
+ }
+}
+
+/* RESULT = P1 + P2 (Weierstrass version).*/
+static void add_points_weierstrass(MPI_POINT result,
+ MPI_POINT p1, MPI_POINT p2,
+ struct mpi_ec_ctx *ctx)
+{
+#define x1 (p1->x)
+#define y1 (p1->y)
+#define z1 (p1->z)
+#define x2 (p2->x)
+#define y2 (p2->y)
+#define z2 (p2->z)
+#define x3 (result->x)
+#define y3 (result->y)
+#define z3 (result->z)
+#define l1 (ctx->t.scratch[0])
+#define l2 (ctx->t.scratch[1])
+#define l3 (ctx->t.scratch[2])
+#define l4 (ctx->t.scratch[3])
+#define l5 (ctx->t.scratch[4])
+#define l6 (ctx->t.scratch[5])
+#define l7 (ctx->t.scratch[6])
+#define l8 (ctx->t.scratch[7])
+#define l9 (ctx->t.scratch[8])
+#define t1 (ctx->t.scratch[9])
+#define t2 (ctx->t.scratch[10])
+
+ if ((!mpi_cmp(x1, x2)) && (!mpi_cmp(y1, y2)) && (!mpi_cmp(z1, z2))) {
+ /* Same point; need to call the duplicate function. */
+ mpi_ec_dup_point(result, p1, ctx);
+ } else if (!mpi_cmp_ui(z1, 0)) {
+ /* P1 is at infinity. */
+ mpi_set(x3, p2->x);
+ mpi_set(y3, p2->y);
+ mpi_set(z3, p2->z);
+ } else if (!mpi_cmp_ui(z2, 0)) {
+ /* P2 is at infinity. */
+ mpi_set(x3, p1->x);
+ mpi_set(y3, p1->y);
+ mpi_set(z3, p1->z);
+ } else {
+ int z1_is_one = !mpi_cmp_ui(z1, 1);
+ int z2_is_one = !mpi_cmp_ui(z2, 1);
+
+ /* l1 = x1 z2^2 */
+ /* l2 = x2 z1^2 */
+ if (z2_is_one)
+ mpi_set(l1, x1);
+ else {
+ ec_pow2(l1, z2, ctx);
+ ec_mulm(l1, l1, x1, ctx);
+ }
+ if (z1_is_one)
+ mpi_set(l2, x2);
+ else {
+ ec_pow2(l2, z1, ctx);
+ ec_mulm(l2, l2, x2, ctx);
+ }
+ /* l3 = l1 - l2 */
+ ec_subm(l3, l1, l2, ctx);
+ /* l4 = y1 z2^3 */
+ ec_powm(l4, z2, mpi_const(MPI_C_THREE), ctx);
+ ec_mulm(l4, l4, y1, ctx);
+ /* l5 = y2 z1^3 */
+ ec_powm(l5, z1, mpi_const(MPI_C_THREE), ctx);
+ ec_mulm(l5, l5, y2, ctx);
+ /* l6 = l4 - l5 */
+ ec_subm(l6, l4, l5, ctx);
+
+ if (!mpi_cmp_ui(l3, 0)) {
+ if (!mpi_cmp_ui(l6, 0)) {
+ /* P1 and P2 are the same - use duplicate function. */
+ mpi_ec_dup_point(result, p1, ctx);
+ } else {
+ /* P1 is the inverse of P2. */
+ mpi_set_ui(x3, 1);
+ mpi_set_ui(y3, 1);
+ mpi_set_ui(z3, 0);
+ }
+ } else {
+ /* l7 = l1 + l2 */
+ ec_addm(l7, l1, l2, ctx);
+ /* l8 = l4 + l5 */
+ ec_addm(l8, l4, l5, ctx);
+ /* z3 = z1 z2 l3 */
+ ec_mulm(z3, z1, z2, ctx);
+ ec_mulm(z3, z3, l3, ctx);
+ /* x3 = l6^2 - l7 l3^2 */
+ ec_pow2(t1, l6, ctx);
+ ec_pow2(t2, l3, ctx);
+ ec_mulm(t2, t2, l7, ctx);
+ ec_subm(x3, t1, t2, ctx);
+ /* l9 = l7 l3^2 - 2 x3 */
+ ec_mul2(t1, x3, ctx);
+ ec_subm(l9, t2, t1, ctx);
+ /* y3 = (l9 l6 - l8 l3^3)/2 */
+ ec_mulm(l9, l9, l6, ctx);
+ ec_powm(t1, l3, mpi_const(MPI_C_THREE), ctx); /* fixme: Use saved value*/
+ ec_mulm(t1, t1, l8, ctx);
+ ec_subm(y3, l9, t1, ctx);
+ ec_mulm(y3, y3, ec_get_two_inv_p(ctx), ctx);
+ }
+ }
+
+#undef x1
+#undef y1
+#undef z1
+#undef x2
+#undef y2
+#undef z2
+#undef x3
+#undef y3
+#undef z3
+#undef l1
+#undef l2
+#undef l3
+#undef l4
+#undef l5
+#undef l6
+#undef l7
+#undef l8
+#undef l9
+#undef t1
+#undef t2
+}
+
+/* RESULT = P1 + P2 (Montgomery version).*/
+static void add_points_montgomery(MPI_POINT result,
+ MPI_POINT p1, MPI_POINT p2,
+ struct mpi_ec_ctx *ctx)
+{
+ (void)result;
+ (void)p1;
+ (void)p2;
+ (void)ctx;
+ log_fatal("%s: %s not yet supported\n",
+ "mpi_ec_add_points", "Montgomery");
+}
+
+/* RESULT = P1 + P2 (Twisted Edwards version).*/
+static void add_points_edwards(MPI_POINT result,
+ MPI_POINT p1, MPI_POINT p2,
+ struct mpi_ec_ctx *ctx)
+{
+#define X1 (p1->x)
+#define Y1 (p1->y)
+#define Z1 (p1->z)
+#define X2 (p2->x)
+#define Y2 (p2->y)
+#define Z2 (p2->z)
+#define X3 (result->x)
+#define Y3 (result->y)
+#define Z3 (result->z)
+#define A (ctx->t.scratch[0])
+#define B (ctx->t.scratch[1])
+#define C (ctx->t.scratch[2])
+#define D (ctx->t.scratch[3])
+#define E (ctx->t.scratch[4])
+#define F (ctx->t.scratch[5])
+#define G (ctx->t.scratch[6])
+#define tmp (ctx->t.scratch[7])
+
+ point_resize(result, ctx);
+
+ /* Compute: (X_3 : Y_3 : Z_3) = (X_1 : Y_1 : Z_1) + (X_2 : Y_2 : Z_3) */
+
+ /* A = Z1 · Z2 */
+ ctx->mulm(A, Z1, Z2, ctx);
+
+ /* B = A^2 */
+ ctx->pow2(B, A, ctx);
+
+ /* C = X1 · X2 */
+ ctx->mulm(C, X1, X2, ctx);
+
+ /* D = Y1 · Y2 */
+ ctx->mulm(D, Y1, Y2, ctx);
+
+ /* E = d · C · D */
+ ctx->mulm(E, ctx->b, C, ctx);
+ ctx->mulm(E, E, D, ctx);
+
+ /* F = B - E */
+ ctx->subm(F, B, E, ctx);
+
+ /* G = B + E */
+ ctx->addm(G, B, E, ctx);
+
+ /* X_3 = A · F · ((X_1 + Y_1) · (X_2 + Y_2) - C - D) */
+ ctx->addm(tmp, X1, Y1, ctx);
+ ctx->addm(X3, X2, Y2, ctx);
+ ctx->mulm(X3, X3, tmp, ctx);
+ ctx->subm(X3, X3, C, ctx);
+ ctx->subm(X3, X3, D, ctx);
+ ctx->mulm(X3, X3, F, ctx);
+ ctx->mulm(X3, X3, A, ctx);
+
+ /* Y_3 = A · G · (D - aC) */
+ if (ctx->dialect == ECC_DIALECT_ED25519) {
+ ctx->addm(Y3, D, C, ctx);
+ } else {
+ ctx->mulm(Y3, ctx->a, C, ctx);
+ ctx->subm(Y3, D, Y3, ctx);
+ }
+ ctx->mulm(Y3, Y3, G, ctx);
+ ctx->mulm(Y3, Y3, A, ctx);
+
+ /* Z_3 = F · G */
+ ctx->mulm(Z3, F, G, ctx);
+
+
+#undef X1
+#undef Y1
+#undef Z1
+#undef X2
+#undef Y2
+#undef Z2
+#undef X3
+#undef Y3
+#undef Z3
+#undef A
+#undef B
+#undef C
+#undef D
+#undef E
+#undef F
+#undef G
+#undef tmp
+}
+
+/* Compute a step of Montgomery Ladder (only use X and Z in the point).
+ * Inputs: P1, P2, and x-coordinate of DIF = P1 - P1.
+ * Outputs: PRD = 2 * P1 and SUM = P1 + P2.
+ */
+static void montgomery_ladder(MPI_POINT prd, MPI_POINT sum,
+ MPI_POINT p1, MPI_POINT p2, MPI dif_x,
+ struct mpi_ec_ctx *ctx)
+{
+ ctx->addm(sum->x, p2->x, p2->z, ctx);
+ ctx->subm(p2->z, p2->x, p2->z, ctx);
+ ctx->addm(prd->x, p1->x, p1->z, ctx);
+ ctx->subm(p1->z, p1->x, p1->z, ctx);
+ ctx->mulm(p2->x, p1->z, sum->x, ctx);
+ ctx->mulm(p2->z, prd->x, p2->z, ctx);
+ ctx->pow2(p1->x, prd->x, ctx);
+ ctx->pow2(p1->z, p1->z, ctx);
+ ctx->addm(sum->x, p2->x, p2->z, ctx);
+ ctx->subm(p2->z, p2->x, p2->z, ctx);
+ ctx->mulm(prd->x, p1->x, p1->z, ctx);
+ ctx->subm(p1->z, p1->x, p1->z, ctx);
+ ctx->pow2(sum->x, sum->x, ctx);
+ ctx->pow2(sum->z, p2->z, ctx);
+ ctx->mulm(prd->z, p1->z, ctx->a, ctx); /* CTX->A: (a-2)/4 */
+ ctx->mulm(sum->z, sum->z, dif_x, ctx);
+ ctx->addm(prd->z, p1->x, prd->z, ctx);
+ ctx->mulm(prd->z, prd->z, p1->z, ctx);
+}
+
+/* RESULT = P1 + P2 */
+void mpi_ec_add_points(MPI_POINT result,
+ MPI_POINT p1, MPI_POINT p2,
+ struct mpi_ec_ctx *ctx)
+{
+ switch (ctx->model) {
+ case MPI_EC_WEIERSTRASS:
+ add_points_weierstrass(result, p1, p2, ctx);
+ break;
+ case MPI_EC_MONTGOMERY:
+ add_points_montgomery(result, p1, p2, ctx);
+ break;
+ case MPI_EC_EDWARDS:
+ add_points_edwards(result, p1, p2, ctx);
+ break;
+ }
+}
+EXPORT_SYMBOL_GPL(mpi_ec_add_points);
+
+/* Scalar point multiplication - the main function for ECC. If takes
+ * an integer SCALAR and a POINT as well as the usual context CTX.
+ * RESULT will be set to the resulting point.
+ */
+void mpi_ec_mul_point(MPI_POINT result,
+ MPI scalar, MPI_POINT point,
+ struct mpi_ec_ctx *ctx)
+{
+ MPI x1, y1, z1, k, h, yy;
+ unsigned int i, loops;
+ struct gcry_mpi_point p1, p2, p1inv;
+
+ if (ctx->model == MPI_EC_EDWARDS) {
+ /* Simple left to right binary method. Algorithm 3.27 from
+ * {author={Hankerson, Darrel and Menezes, Alfred J. and Vanstone, Scott},
+ * title = {Guide to Elliptic Curve Cryptography},
+ * year = {2003}, isbn = {038795273X},
+ * url = {http://www.cacr.math.uwaterloo.ca/ecc/},
+ * publisher = {Springer-Verlag New York, Inc.}}
+ */
+ unsigned int nbits;
+ int j;
+
+ if (mpi_cmp(scalar, ctx->p) >= 0)
+ nbits = mpi_get_nbits(scalar);
+ else
+ nbits = mpi_get_nbits(ctx->p);
+
+ mpi_set_ui(result->x, 0);
+ mpi_set_ui(result->y, 1);
+ mpi_set_ui(result->z, 1);
+ point_resize(point, ctx);
+
+ point_resize(result, ctx);
+ point_resize(point, ctx);
+
+ for (j = nbits-1; j >= 0; j--) {
+ mpi_ec_dup_point(result, result, ctx);
+ if (mpi_test_bit(scalar, j))
+ mpi_ec_add_points(result, result, point, ctx);
+ }
+ return;
+ } else if (ctx->model == MPI_EC_MONTGOMERY) {
+ unsigned int nbits;
+ int j;
+ struct gcry_mpi_point p1_, p2_;
+ MPI_POINT q1, q2, prd, sum;
+ unsigned long sw;
+ mpi_size_t rsize;
+
+ /* Compute scalar point multiplication with Montgomery Ladder.
+ * Note that we don't use Y-coordinate in the points at all.
+ * RESULT->Y will be filled by zero.
+ */
+
+ nbits = mpi_get_nbits(scalar);
+ point_init(&p1);
+ point_init(&p2);
+ point_init(&p1_);
+ point_init(&p2_);
+ mpi_set_ui(p1.x, 1);
+ mpi_free(p2.x);
+ p2.x = mpi_copy(point->x);
+ mpi_set_ui(p2.z, 1);
+
+ point_resize(&p1, ctx);
+ point_resize(&p2, ctx);
+ point_resize(&p1_, ctx);
+ point_resize(&p2_, ctx);
+
+ mpi_resize(point->x, ctx->p->nlimbs);
+ point->x->nlimbs = ctx->p->nlimbs;
+
+ q1 = &p1;
+ q2 = &p2;
+ prd = &p1_;
+ sum = &p2_;
+
+ for (j = nbits-1; j >= 0; j--) {
+ MPI_POINT t;
+
+ sw = mpi_test_bit(scalar, j);
+ point_swap_cond(q1, q2, sw, ctx);
+ montgomery_ladder(prd, sum, q1, q2, point->x, ctx);
+ point_swap_cond(prd, sum, sw, ctx);
+ t = q1; q1 = prd; prd = t;
+ t = q2; q2 = sum; sum = t;
+ }
+
+ mpi_clear(result->y);
+ sw = (nbits & 1);
+ point_swap_cond(&p1, &p1_, sw, ctx);
+
+ rsize = p1.z->nlimbs;
+ MPN_NORMALIZE(p1.z->d, rsize);
+ if (rsize == 0) {
+ mpi_set_ui(result->x, 1);
+ mpi_set_ui(result->z, 0);
+ } else {
+ z1 = mpi_new(0);
+ ec_invm(z1, p1.z, ctx);
+ ec_mulm(result->x, p1.x, z1, ctx);
+ mpi_set_ui(result->z, 1);
+ mpi_free(z1);
+ }
+
+ point_free(&p1);
+ point_free(&p2);
+ point_free(&p1_);
+ point_free(&p2_);
+ return;
+ }
+
+ x1 = mpi_alloc_like(ctx->p);
+ y1 = mpi_alloc_like(ctx->p);
+ h = mpi_alloc_like(ctx->p);
+ k = mpi_copy(scalar);
+ yy = mpi_copy(point->y);
+
+ if (mpi_has_sign(k)) {
+ k->sign = 0;
+ ec_invm(yy, yy, ctx);
+ }
+
+ if (!mpi_cmp_ui(point->z, 1)) {
+ mpi_set(x1, point->x);
+ mpi_set(y1, yy);
+ } else {
+ MPI z2, z3;
+
+ z2 = mpi_alloc_like(ctx->p);
+ z3 = mpi_alloc_like(ctx->p);
+ ec_mulm(z2, point->z, point->z, ctx);
+ ec_mulm(z3, point->z, z2, ctx);
+ ec_invm(z2, z2, ctx);
+ ec_mulm(x1, point->x, z2, ctx);
+ ec_invm(z3, z3, ctx);
+ ec_mulm(y1, yy, z3, ctx);
+ mpi_free(z2);
+ mpi_free(z3);
+ }
+ z1 = mpi_copy(mpi_const(MPI_C_ONE));
+
+ mpi_mul(h, k, mpi_const(MPI_C_THREE)); /* h = 3k */
+ loops = mpi_get_nbits(h);
+ if (loops < 2) {
+ /* If SCALAR is zero, the above mpi_mul sets H to zero and thus
+ * LOOPs will be zero. To avoid an underflow of I in the main
+ * loop we set LOOP to 2 and the result to (0,0,0).
+ */
+ loops = 2;
+ mpi_clear(result->x);
+ mpi_clear(result->y);
+ mpi_clear(result->z);
+ } else {
+ mpi_set(result->x, point->x);
+ mpi_set(result->y, yy);
+ mpi_set(result->z, point->z);
+ }
+ mpi_free(yy); yy = NULL;
+
+ p1.x = x1; x1 = NULL;
+ p1.y = y1; y1 = NULL;
+ p1.z = z1; z1 = NULL;
+ point_init(&p2);
+ point_init(&p1inv);
+
+ /* Invert point: y = p - y mod p */
+ point_set(&p1inv, &p1);
+ ec_subm(p1inv.y, ctx->p, p1inv.y, ctx);
+
+ for (i = loops-2; i > 0; i--) {
+ mpi_ec_dup_point(result, result, ctx);
+ if (mpi_test_bit(h, i) == 1 && mpi_test_bit(k, i) == 0) {
+ point_set(&p2, result);
+ mpi_ec_add_points(result, &p2, &p1, ctx);
+ }
+ if (mpi_test_bit(h, i) == 0 && mpi_test_bit(k, i) == 1) {
+ point_set(&p2, result);
+ mpi_ec_add_points(result, &p2, &p1inv, ctx);
+ }
+ }
+
+ point_free(&p1);
+ point_free(&p2);
+ point_free(&p1inv);
+ mpi_free(h);
+ mpi_free(k);
+}
+EXPORT_SYMBOL_GPL(mpi_ec_mul_point);
+
+/* Return true if POINT is on the curve described by CTX. */
+int mpi_ec_curve_point(MPI_POINT point, struct mpi_ec_ctx *ctx)
+{
+ int res = 0;
+ MPI x, y, w;
+
+ x = mpi_new(0);
+ y = mpi_new(0);
+ w = mpi_new(0);
+
+ /* Check that the point is in range. This needs to be done here and
+ * not after conversion to affine coordinates.
+ */
+ if (mpi_cmpabs(point->x, ctx->p) >= 0)
+ goto leave;
+ if (mpi_cmpabs(point->y, ctx->p) >= 0)
+ goto leave;
+ if (mpi_cmpabs(point->z, ctx->p) >= 0)
+ goto leave;
+
+ switch (ctx->model) {
+ case MPI_EC_WEIERSTRASS:
+ {
+ MPI xxx;
+
+ if (mpi_ec_get_affine(x, y, point, ctx))
+ goto leave;
+
+ xxx = mpi_new(0);
+
+ /* y^2 == x^3 + a·x + b */
+ ec_pow2(y, y, ctx);
+
+ ec_pow3(xxx, x, ctx);
+ ec_mulm(w, ctx->a, x, ctx);
+ ec_addm(w, w, ctx->b, ctx);
+ ec_addm(w, w, xxx, ctx);
+
+ if (!mpi_cmp(y, w))
+ res = 1;
+
+ mpi_free(xxx);
+ }
+ break;
+
+ case MPI_EC_MONTGOMERY:
+ {
+#define xx y
+ /* With Montgomery curve, only X-coordinate is valid. */
+ if (mpi_ec_get_affine(x, NULL, point, ctx))
+ goto leave;
+
+ /* The equation is: b * y^2 == x^3 + a · x^2 + x */
+ /* We check if right hand is quadratic residue or not by
+ * Euler's criterion.
+ */
+ /* CTX->A has (a-2)/4 and CTX->B has b^-1 */
+ ec_mulm(w, ctx->a, mpi_const(MPI_C_FOUR), ctx);
+ ec_addm(w, w, mpi_const(MPI_C_TWO), ctx);
+ ec_mulm(w, w, x, ctx);
+ ec_pow2(xx, x, ctx);
+ ec_addm(w, w, xx, ctx);
+ ec_addm(w, w, mpi_const(MPI_C_ONE), ctx);
+ ec_mulm(w, w, x, ctx);
+ ec_mulm(w, w, ctx->b, ctx);
+#undef xx
+ /* Compute Euler's criterion: w^(p-1)/2 */
+#define p_minus1 y
+ ec_subm(p_minus1, ctx->p, mpi_const(MPI_C_ONE), ctx);
+ mpi_rshift(p_minus1, p_minus1, 1);
+ ec_powm(w, w, p_minus1, ctx);
+
+ res = !mpi_cmp_ui(w, 1);
+#undef p_minus1
+ }
+ break;
+
+ case MPI_EC_EDWARDS:
+ {
+ if (mpi_ec_get_affine(x, y, point, ctx))
+ goto leave;
+
+ mpi_resize(w, ctx->p->nlimbs);
+ w->nlimbs = ctx->p->nlimbs;
+
+ /* a · x^2 + y^2 - 1 - b · x^2 · y^2 == 0 */
+ ctx->pow2(x, x, ctx);
+ ctx->pow2(y, y, ctx);
+ if (ctx->dialect == ECC_DIALECT_ED25519)
+ ctx->subm(w, ctx->p, x, ctx);
+ else
+ ctx->mulm(w, ctx->a, x, ctx);
+ ctx->addm(w, w, y, ctx);
+ ctx->mulm(x, x, y, ctx);
+ ctx->mulm(x, x, ctx->b, ctx);
+ ctx->subm(w, w, x, ctx);
+ if (!mpi_cmp_ui(w, 1))
+ res = 1;
+ }
+ break;
+ }
+
+leave:
+ mpi_free(w);
+ mpi_free(x);
+ mpi_free(y);
+
+ return res;
+}
+EXPORT_SYMBOL_GPL(mpi_ec_curve_point);
diff --git a/lib/mpi/generic_mpih-add1.c b/lib/mpi/generic_mpih-add1.c
new file mode 100644
index 000000000..299308b54
--- /dev/null
+++ b/lib/mpi/generic_mpih-add1.c
@@ -0,0 +1,48 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* mpihelp-add_1.c - MPI helper functions
+ * Copyright (C) 1994, 1996, 1997, 1998,
+ * 2000 Free Software Foundation, Inc.
+ *
+ * This file is part of GnuPG.
+ *
+ * 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"
+#include "longlong.h"
+
+mpi_limb_t
+mpihelp_add_n(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr,
+ mpi_ptr_t s2_ptr, mpi_size_t size)
+{
+ mpi_limb_t x, y, cy;
+ mpi_size_t j;
+
+ /* The loop counter and index J goes from -SIZE to -1. This way
+ the loop becomes faster. */
+ j = -size;
+
+ /* Offset the base pointers to compensate for the negative indices. */
+ s1_ptr -= j;
+ s2_ptr -= j;
+ res_ptr -= j;
+
+ cy = 0;
+ do {
+ y = s2_ptr[j];
+ x = s1_ptr[j];
+ y += cy; /* add previous carry to one addend */
+ cy = y < cy; /* get out carry from that addition */
+ y += x; /* add other addend */
+ cy += y < x; /* get out carry from that add, combine */
+ res_ptr[j] = y;
+ } while (++j);
+
+ return cy;
+}
diff --git a/lib/mpi/generic_mpih-lshift.c b/lib/mpi/generic_mpih-lshift.c
new file mode 100644
index 000000000..7b21f5938
--- /dev/null
+++ b/lib/mpi/generic_mpih-lshift.c
@@ -0,0 +1,50 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* mpihelp-lshift.c - MPI helper functions
+ * Copyright (C) 1994, 1996, 1998, 2001 Free Software Foundation, Inc.
+ *
+ * This file is part of GnuPG.
+ *
+ * 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"
+
+/* Shift U (pointed to by UP and USIZE digits long) CNT bits to the left
+ * and store the USIZE least significant digits of the result at WP.
+ * Return the bits shifted out from the most significant digit.
+ *
+ * Argument constraints:
+ * 1. 0 < CNT < BITS_PER_MP_LIMB
+ * 2. If the result is to be written over the input, WP must be >= UP.
+ */
+
+mpi_limb_t
+mpihelp_lshift(mpi_ptr_t wp, mpi_ptr_t up, mpi_size_t usize, unsigned int cnt)
+{
+ mpi_limb_t high_limb, low_limb;
+ unsigned sh_1, sh_2;
+ mpi_size_t i;
+ mpi_limb_t retval;
+
+ sh_1 = cnt;
+ wp += 1;
+ sh_2 = BITS_PER_MPI_LIMB - sh_1;
+ i = usize - 1;
+ low_limb = up[i];
+ retval = low_limb >> sh_2;
+ high_limb = low_limb;
+ while (--i >= 0) {
+ low_limb = up[i];
+ wp[i] = (high_limb << sh_1) | (low_limb >> sh_2);
+ high_limb = low_limb;
+ }
+ wp[i] = high_limb << sh_1;
+
+ return retval;
+}
diff --git a/lib/mpi/generic_mpih-mul1.c b/lib/mpi/generic_mpih-mul1.c
new file mode 100644
index 000000000..e020e61d4
--- /dev/null
+++ b/lib/mpi/generic_mpih-mul1.c
@@ -0,0 +1,44 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* mpihelp-mul_1.c - MPI helper functions
+ * Copyright (C) 1994, 1996, 1997, 1998, 2001 Free Software Foundation, Inc.
+ *
+ * This file is part of GnuPG.
+ *
+ * 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"
+#include "longlong.h"
+
+mpi_limb_t
+mpihelp_mul_1(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr, mpi_size_t s1_size,
+ mpi_limb_t s2_limb)
+{
+ mpi_limb_t cy_limb;
+ mpi_size_t j;
+ mpi_limb_t prod_high, prod_low;
+
+ /* The loop counter and index J goes from -S1_SIZE to -1. This way
+ * the loop becomes faster. */
+ j = -s1_size;
+
+ /* Offset the base pointers to compensate for the negative indices. */
+ s1_ptr -= j;
+ res_ptr -= j;
+
+ cy_limb = 0;
+ do {
+ umul_ppmm(prod_high, prod_low, s1_ptr[j], s2_limb);
+ prod_low += cy_limb;
+ cy_limb = (prod_low < cy_limb ? 1 : 0) + prod_high;
+ res_ptr[j] = prod_low;
+ } while (++j);
+
+ return cy_limb;
+}
diff --git a/lib/mpi/generic_mpih-mul2.c b/lib/mpi/generic_mpih-mul2.c
new file mode 100644
index 000000000..9484d8528
--- /dev/null
+++ b/lib/mpi/generic_mpih-mul2.c
@@ -0,0 +1,47 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* mpihelp-mul_2.c - MPI helper functions
+ * Copyright (C) 1994, 1996, 1997, 1998, 2001 Free Software Foundation, Inc.
+ *
+ * This file is part of GnuPG.
+ *
+ * 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"
+#include "longlong.h"
+
+mpi_limb_t
+mpihelp_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 cy_limb;
+ mpi_size_t j;
+ mpi_limb_t prod_high, prod_low;
+ mpi_limb_t x;
+
+ /* The loop counter and index J goes from -SIZE to -1. This way
+ * the loop becomes faster. */
+ j = -s1_size;
+ res_ptr -= j;
+ s1_ptr -= j;
+
+ cy_limb = 0;
+ do {
+ umul_ppmm(prod_high, prod_low, s1_ptr[j], s2_limb);
+
+ prod_low += cy_limb;
+ cy_limb = (prod_low < cy_limb ? 1 : 0) + prod_high;
+
+ x = res_ptr[j];
+ prod_low = x + prod_low;
+ cy_limb += prod_low < x ? 1 : 0;
+ res_ptr[j] = prod_low;
+ } while (++j);
+ return cy_limb;
+}
diff --git a/lib/mpi/generic_mpih-mul3.c b/lib/mpi/generic_mpih-mul3.c
new file mode 100644
index 000000000..ccdbab412
--- /dev/null
+++ b/lib/mpi/generic_mpih-mul3.c
@@ -0,0 +1,48 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* mpihelp-mul_3.c - MPI helper functions
+ * Copyright (C) 1994, 1996, 1997, 1998, 2001 Free Software Foundation, Inc.
+ *
+ * This file is part of GnuPG.
+ *
+ * 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"
+#include "longlong.h"
+
+mpi_limb_t
+mpihelp_submul_1(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr,
+ mpi_size_t s1_size, mpi_limb_t s2_limb)
+{
+ mpi_limb_t cy_limb;
+ mpi_size_t j;
+ mpi_limb_t prod_high, prod_low;
+ mpi_limb_t x;
+
+ /* The loop counter and index J goes from -SIZE to -1. This way
+ * the loop becomes faster. */
+ j = -s1_size;
+ res_ptr -= j;
+ s1_ptr -= j;
+
+ cy_limb = 0;
+ do {
+ umul_ppmm(prod_high, prod_low, s1_ptr[j], s2_limb);
+
+ prod_low += cy_limb;
+ cy_limb = (prod_low < cy_limb ? 1 : 0) + prod_high;
+
+ x = res_ptr[j];
+ prod_low = x - prod_low;
+ cy_limb += prod_low > x ? 1 : 0;
+ res_ptr[j] = prod_low;
+ } while (++j);
+
+ return cy_limb;
+}
diff --git a/lib/mpi/generic_mpih-rshift.c b/lib/mpi/generic_mpih-rshift.c
new file mode 100644
index 000000000..e07bc69aa
--- /dev/null
+++ b/lib/mpi/generic_mpih-rshift.c
@@ -0,0 +1,50 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* mpih-rshift.c - MPI helper functions
+ * Copyright (C) 1994, 1996, 1998, 1999,
+ * 2000, 2001 Free Software Foundation, Inc.
+ *
+ * This file is part of GNUPG
+ *
+ * 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"
+
+/* Shift U (pointed to by UP and USIZE limbs long) CNT bits to the right
+ * and store the USIZE least significant limbs of the result at WP.
+ * The bits shifted out to the right are returned.
+ *
+ * Argument constraints:
+ * 1. 0 < CNT < BITS_PER_MP_LIMB
+ * 2. If the result is to be written over the input, WP must be <= UP.
+ */
+
+mpi_limb_t
+mpihelp_rshift(mpi_ptr_t wp, mpi_ptr_t up, mpi_size_t usize, unsigned cnt)
+{
+ mpi_limb_t high_limb, low_limb;
+ unsigned sh_1, sh_2;
+ mpi_size_t i;
+ mpi_limb_t retval;
+
+ sh_1 = cnt;
+ wp -= 1;
+ sh_2 = BITS_PER_MPI_LIMB - sh_1;
+ high_limb = up[0];
+ retval = high_limb << sh_2;
+ low_limb = high_limb;
+ for (i = 1; i < usize; i++) {
+ high_limb = up[i];
+ wp[i] = (low_limb >> sh_1) | (high_limb << sh_2);
+ low_limb = high_limb;
+ }
+ wp[i] = low_limb >> sh_1;
+
+ return retval;
+}
diff --git a/lib/mpi/generic_mpih-sub1.c b/lib/mpi/generic_mpih-sub1.c
new file mode 100644
index 000000000..eea4382aa
--- /dev/null
+++ b/lib/mpi/generic_mpih-sub1.c
@@ -0,0 +1,47 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* mpihelp-add_2.c - MPI helper functions
+ * Copyright (C) 1994, 1996, 1997, 1998, 2001 Free Software Foundation, Inc.
+ *
+ * This file is part of GnuPG.
+ *
+ * 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"
+#include "longlong.h"
+
+mpi_limb_t
+mpihelp_sub_n(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr,
+ mpi_ptr_t s2_ptr, mpi_size_t size)
+{
+ mpi_limb_t x, y, cy;
+ mpi_size_t j;
+
+ /* The loop counter and index J goes from -SIZE to -1. This way
+ the loop becomes faster. */
+ j = -size;
+
+ /* Offset the base pointers to compensate for the negative indices. */
+ s1_ptr -= j;
+ s2_ptr -= j;
+ res_ptr -= j;
+
+ cy = 0;
+ do {
+ y = s2_ptr[j];
+ x = s1_ptr[j];
+ y += cy; /* add previous carry to subtrahend */
+ cy = y < cy; /* get out carry from that addition */
+ y = x - y; /* main subtract */
+ cy += y > x; /* get out carry from the subtract, combine */
+ res_ptr[j] = y;
+ } while (++j);
+
+ return cy;
+}
diff --git a/lib/mpi/longlong.h b/lib/mpi/longlong.h
new file mode 100644
index 000000000..b6fa1d08f
--- /dev/null
+++ b/lib/mpi/longlong.h
@@ -0,0 +1,1361 @@
+/* longlong.h -- definitions for mixed size 32/64 bit arithmetic.
+ * Note: I added some stuff for use with gnupg
+ *
+ * Copyright (C) 1991, 1992, 1993, 1994, 1996, 1998,
+ * 2000, 2001, 2002, 2003 Free Software Foundation, Inc.
+ *
+ * This file is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Library General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ * This file 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 Library General Public
+ * License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public License
+ * along with this file; see the file COPYING.LIB. If not, write to
+ * the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+ * MA 02111-1307, USA. */
+
+#include <linux/count_zeros.h>
+
+/* You have to define the following before including this file:
+ *
+ * UWtype -- An unsigned type, default type for operations (typically a "word")
+ * UHWtype -- An unsigned type, at least half the size of UWtype.
+ * UDWtype -- An unsigned type, at least twice as large a UWtype
+ * W_TYPE_SIZE -- size in bits of UWtype
+ *
+ * SItype, USItype -- Signed and unsigned 32 bit types.
+ * DItype, UDItype -- Signed and unsigned 64 bit types.
+ *
+ * On a 32 bit machine UWtype should typically be USItype;
+ * on a 64 bit machine, UWtype should typically be UDItype.
+*/
+
+#define __BITS4 (W_TYPE_SIZE / 4)
+#define __ll_B ((UWtype) 1 << (W_TYPE_SIZE / 2))
+#define __ll_lowpart(t) ((UWtype) (t) & (__ll_B - 1))
+#define __ll_highpart(t) ((UWtype) (t) >> (W_TYPE_SIZE / 2))
+
+/* This is used to make sure no undesirable sharing between different libraries
+ that use this file takes place. */
+#ifndef __MPN
+#define __MPN(x) __##x
+#endif
+
+/* Define auxiliary asm macros.
+ *
+ * 1) umul_ppmm(high_prod, low_prod, multiplier, multiplicand) multiplies two
+ * UWtype integers MULTIPLIER and MULTIPLICAND, and generates a two UWtype
+ * word product in HIGH_PROD and LOW_PROD.
+ *
+ * 2) __umulsidi3(a,b) multiplies two UWtype integers A and B, and returns a
+ * UDWtype product. This is just a variant of umul_ppmm.
+
+ * 3) udiv_qrnnd(quotient, remainder, high_numerator, low_numerator,
+ * denominator) divides a UDWtype, composed by the UWtype integers
+ * HIGH_NUMERATOR and LOW_NUMERATOR, by DENOMINATOR and places the quotient
+ * in QUOTIENT and the remainder in REMAINDER. HIGH_NUMERATOR must be less
+ * than DENOMINATOR for correct operation. If, in addition, the most
+ * significant bit of DENOMINATOR must be 1, then the pre-processor symbol
+ * UDIV_NEEDS_NORMALIZATION is defined to 1.
+ * 4) sdiv_qrnnd(quotient, remainder, high_numerator, low_numerator,
+ * denominator). Like udiv_qrnnd but the numbers are signed. The quotient
+ * is rounded towards 0.
+ *
+ * 5) count_leading_zeros(count, x) counts the number of zero-bits from the
+ * msb to the first non-zero bit in the UWtype X. This is the number of
+ * steps X needs to be shifted left to set the msb. Undefined for X == 0,
+ * unless the symbol COUNT_LEADING_ZEROS_0 is defined to some value.
+ *
+ * 6) count_trailing_zeros(count, x) like count_leading_zeros, but counts
+ * from the least significant end.
+ *
+ * 7) add_ssaaaa(high_sum, low_sum, high_addend_1, low_addend_1,
+ * high_addend_2, low_addend_2) adds two UWtype integers, composed by
+ * HIGH_ADDEND_1 and LOW_ADDEND_1, and HIGH_ADDEND_2 and LOW_ADDEND_2
+ * respectively. The result is placed in HIGH_SUM and LOW_SUM. Overflow
+ * (i.e. carry out) is not stored anywhere, and is lost.
+ *
+ * 8) sub_ddmmss(high_difference, low_difference, high_minuend, low_minuend,
+ * high_subtrahend, low_subtrahend) subtracts two two-word UWtype integers,
+ * composed by HIGH_MINUEND_1 and LOW_MINUEND_1, and HIGH_SUBTRAHEND_2 and
+ * LOW_SUBTRAHEND_2 respectively. The result is placed in HIGH_DIFFERENCE
+ * and LOW_DIFFERENCE. Overflow (i.e. carry out) is not stored anywhere,
+ * and is lost.
+ *
+ * If any of these macros are left undefined for a particular CPU,
+ * C macros are used. */
+
+/* The CPUs come in alphabetical order below.
+ *
+ * Please add support for more CPUs here, or improve the current support
+ * for the CPUs below! */
+
+#if defined(__GNUC__) && !defined(NO_ASM)
+
+/* We sometimes need to clobber "cc" with gcc2, but that would not be
+ understood by gcc1. Use cpp to avoid major code duplication. */
+#if __GNUC__ < 2
+#define __CLOBBER_CC
+#define __AND_CLOBBER_CC
+#else /* __GNUC__ >= 2 */
+#define __CLOBBER_CC : "cc"
+#define __AND_CLOBBER_CC , "cc"
+#endif /* __GNUC__ < 2 */
+
+/***************************************
+ ************** A29K *****************
+ ***************************************/
+#if (defined(__a29k__) || defined(_AM29K)) && W_TYPE_SIZE == 32
+#define add_ssaaaa(sh, sl, ah, al, bh, bl) \
+ __asm__ ("add %1,%4,%5\n" \
+ "addc %0,%2,%3" \
+ : "=r" ((USItype)(sh)), \
+ "=&r" ((USItype)(sl)) \
+ : "%r" ((USItype)(ah)), \
+ "rI" ((USItype)(bh)), \
+ "%r" ((USItype)(al)), \
+ "rI" ((USItype)(bl)))
+#define sub_ddmmss(sh, sl, ah, al, bh, bl) \
+ __asm__ ("sub %1,%4,%5\n" \
+ "subc %0,%2,%3" \
+ : "=r" ((USItype)(sh)), \
+ "=&r" ((USItype)(sl)) \
+ : "r" ((USItype)(ah)), \
+ "rI" ((USItype)(bh)), \
+ "r" ((USItype)(al)), \
+ "rI" ((USItype)(bl)))
+#define umul_ppmm(xh, xl, m0, m1) \
+do { \
+ USItype __m0 = (m0), __m1 = (m1); \
+ __asm__ ("multiplu %0,%1,%2" \
+ : "=r" ((USItype)(xl)) \
+ : "r" (__m0), \
+ "r" (__m1)); \
+ __asm__ ("multmu %0,%1,%2" \
+ : "=r" ((USItype)(xh)) \
+ : "r" (__m0), \
+ "r" (__m1)); \
+} while (0)
+#define udiv_qrnnd(q, r, n1, n0, d) \
+ __asm__ ("dividu %0,%3,%4" \
+ : "=r" ((USItype)(q)), \
+ "=q" ((USItype)(r)) \
+ : "1" ((USItype)(n1)), \
+ "r" ((USItype)(n0)), \
+ "r" ((USItype)(d)))
+#endif /* __a29k__ */
+
+#if defined(__alpha) && W_TYPE_SIZE == 64
+#define umul_ppmm(ph, pl, m0, m1) \
+do { \
+ UDItype __m0 = (m0), __m1 = (m1); \
+ (ph) = __builtin_alpha_umulh(__m0, __m1); \
+ (pl) = __m0 * __m1; \
+} while (0)
+#define UMUL_TIME 46
+#ifndef LONGLONG_STANDALONE
+#define udiv_qrnnd(q, r, n1, n0, d) \
+do { UDItype __r; \
+ (q) = __udiv_qrnnd(&__r, (n1), (n0), (d)); \
+ (r) = __r; \
+} while (0)
+extern UDItype __udiv_qrnnd(UDItype *, UDItype, UDItype, UDItype);
+#define UDIV_TIME 220
+#endif /* LONGLONG_STANDALONE */
+#endif /* __alpha */
+
+/***************************************
+ ************** ARM ******************
+ ***************************************/
+#if defined(__arm__) && W_TYPE_SIZE == 32
+#define add_ssaaaa(sh, sl, ah, al, bh, bl) \
+ __asm__ ("adds %1, %4, %5\n" \
+ "adc %0, %2, %3" \
+ : "=r" (sh), \
+ "=&r" (sl) \
+ : "%r" ((USItype)(ah)), \
+ "rI" ((USItype)(bh)), \
+ "%r" ((USItype)(al)), \
+ "rI" ((USItype)(bl)))
+#define sub_ddmmss(sh, sl, ah, al, bh, bl) \
+ __asm__ ("subs %1, %4, %5\n" \
+ "sbc %0, %2, %3" \
+ : "=r" (sh), \
+ "=&r" (sl) \
+ : "r" ((USItype)(ah)), \
+ "rI" ((USItype)(bh)), \
+ "r" ((USItype)(al)), \
+ "rI" ((USItype)(bl)))
+#if defined __ARM_ARCH_2__ || defined __ARM_ARCH_3__
+#define umul_ppmm(xh, xl, a, b) \
+ __asm__ ("@ Inlined umul_ppmm\n" \
+ "mov %|r0, %2, lsr #16 @ AAAA\n" \
+ "mov %|r2, %3, lsr #16 @ BBBB\n" \
+ "bic %|r1, %2, %|r0, lsl #16 @ aaaa\n" \
+ "bic %0, %3, %|r2, lsl #16 @ bbbb\n" \
+ "mul %1, %|r1, %|r2 @ aaaa * BBBB\n" \
+ "mul %|r2, %|r0, %|r2 @ AAAA * BBBB\n" \
+ "mul %|r1, %0, %|r1 @ aaaa * bbbb\n" \
+ "mul %0, %|r0, %0 @ AAAA * bbbb\n" \
+ "adds %|r0, %1, %0 @ central sum\n" \
+ "addcs %|r2, %|r2, #65536\n" \
+ "adds %1, %|r1, %|r0, lsl #16\n" \
+ "adc %0, %|r2, %|r0, lsr #16" \
+ : "=&r" (xh), \
+ "=r" (xl) \
+ : "r" ((USItype)(a)), \
+ "r" ((USItype)(b)) \
+ : "r0", "r1", "r2")
+#else
+#define umul_ppmm(xh, xl, a, b) \
+ __asm__ ("@ Inlined umul_ppmm\n" \
+ "umull %1, %0, %2, %3" \
+ : "=&r" (xh), \
+ "=&r" (xl) \
+ : "r" ((USItype)(a)), \
+ "r" ((USItype)(b)) \
+ : "r0", "r1")
+#endif
+#define UMUL_TIME 20
+#define UDIV_TIME 100
+#endif /* __arm__ */
+
+/***************************************
+ ************** CLIPPER **************
+ ***************************************/
+#if defined(__clipper__) && W_TYPE_SIZE == 32
+#define umul_ppmm(w1, w0, u, v) \
+ ({union {UDItype __ll; \
+ struct {USItype __l, __h; } __i; \
+ } __xx; \
+ __asm__ ("mulwux %2,%0" \
+ : "=r" (__xx.__ll) \
+ : "%0" ((USItype)(u)), \
+ "r" ((USItype)(v))); \
+ (w1) = __xx.__i.__h; (w0) = __xx.__i.__l; })
+#define smul_ppmm(w1, w0, u, v) \
+ ({union {DItype __ll; \
+ struct {SItype __l, __h; } __i; \
+ } __xx; \
+ __asm__ ("mulwx %2,%0" \
+ : "=r" (__xx.__ll) \
+ : "%0" ((SItype)(u)), \
+ "r" ((SItype)(v))); \
+ (w1) = __xx.__i.__h; (w0) = __xx.__i.__l; })
+#define __umulsidi3(u, v) \
+ ({UDItype __w; \
+ __asm__ ("mulwux %2,%0" \
+ : "=r" (__w) \
+ : "%0" ((USItype)(u)), \
+ "r" ((USItype)(v))); \
+ __w; })
+#endif /* __clipper__ */
+
+/***************************************
+ ************** GMICRO ***************
+ ***************************************/
+#if defined(__gmicro__) && W_TYPE_SIZE == 32
+#define add_ssaaaa(sh, sl, ah, al, bh, bl) \
+ __asm__ ("add.w %5,%1\n" \
+ "addx %3,%0" \
+ : "=g" ((USItype)(sh)), \
+ "=&g" ((USItype)(sl)) \
+ : "%0" ((USItype)(ah)), \
+ "g" ((USItype)(bh)), \
+ "%1" ((USItype)(al)), \
+ "g" ((USItype)(bl)))
+#define sub_ddmmss(sh, sl, ah, al, bh, bl) \
+ __asm__ ("sub.w %5,%1\n" \
+ "subx %3,%0" \
+ : "=g" ((USItype)(sh)), \
+ "=&g" ((USItype)(sl)) \
+ : "0" ((USItype)(ah)), \
+ "g" ((USItype)(bh)), \
+ "1" ((USItype)(al)), \
+ "g" ((USItype)(bl)))
+#define umul_ppmm(ph, pl, m0, m1) \
+ __asm__ ("mulx %3,%0,%1" \
+ : "=g" ((USItype)(ph)), \
+ "=r" ((USItype)(pl)) \
+ : "%0" ((USItype)(m0)), \
+ "g" ((USItype)(m1)))
+#define udiv_qrnnd(q, r, nh, nl, d) \
+ __asm__ ("divx %4,%0,%1" \
+ : "=g" ((USItype)(q)), \
+ "=r" ((USItype)(r)) \
+ : "1" ((USItype)(nh)), \
+ "0" ((USItype)(nl)), \
+ "g" ((USItype)(d)))
+#endif
+
+/***************************************
+ ************** HPPA *****************
+ ***************************************/
+#if defined(__hppa) && W_TYPE_SIZE == 32
+#define add_ssaaaa(sh, sl, ah, al, bh, bl) \
+ __asm__ ("add %4,%5,%1\n" \
+ "addc %2,%3,%0" \
+ : "=r" ((USItype)(sh)), \
+ "=&r" ((USItype)(sl)) \
+ : "%rM" ((USItype)(ah)), \
+ "rM" ((USItype)(bh)), \
+ "%rM" ((USItype)(al)), \
+ "rM" ((USItype)(bl)))
+#define sub_ddmmss(sh, sl, ah, al, bh, bl) \
+ __asm__ ("sub %4,%5,%1\n" \
+ "subb %2,%3,%0" \
+ : "=r" ((USItype)(sh)), \
+ "=&r" ((USItype)(sl)) \
+ : "rM" ((USItype)(ah)), \
+ "rM" ((USItype)(bh)), \
+ "rM" ((USItype)(al)), \
+ "rM" ((USItype)(bl)))
+#if 0 && defined(_PA_RISC1_1)
+/* xmpyu uses floating point register which is not allowed in Linux kernel. */
+#define umul_ppmm(wh, wl, u, v) \
+do { \
+ union {UDItype __ll; \
+ struct {USItype __h, __l; } __i; \
+ } __xx; \
+ __asm__ ("xmpyu %1,%2,%0" \
+ : "=*f" (__xx.__ll) \
+ : "*f" ((USItype)(u)), \
+ "*f" ((USItype)(v))); \
+ (wh) = __xx.__i.__h; \
+ (wl) = __xx.__i.__l; \
+} while (0)
+#define UMUL_TIME 8
+#define UDIV_TIME 60
+#else
+#define UMUL_TIME 40
+#define UDIV_TIME 80
+#endif
+#if 0 /* #ifndef LONGLONG_STANDALONE */
+#define udiv_qrnnd(q, r, n1, n0, d) \
+do { USItype __r; \
+ (q) = __udiv_qrnnd(&__r, (n1), (n0), (d)); \
+ (r) = __r; \
+} while (0)
+extern USItype __udiv_qrnnd();
+#endif /* LONGLONG_STANDALONE */
+#endif /* hppa */
+
+/***************************************
+ ************** I370 *****************
+ ***************************************/
+#if (defined(__i370__) || defined(__mvs__)) && W_TYPE_SIZE == 32
+#define umul_ppmm(xh, xl, m0, m1) \
+do { \
+ union {UDItype __ll; \
+ struct {USItype __h, __l; } __i; \
+ } __xx; \
+ USItype __m0 = (m0), __m1 = (m1); \
+ __asm__ ("mr %0,%3" \
+ : "=r" (__xx.__i.__h), \
+ "=r" (__xx.__i.__l) \
+ : "%1" (__m0), \
+ "r" (__m1)); \
+ (xh) = __xx.__i.__h; (xl) = __xx.__i.__l; \
+ (xh) += ((((SItype) __m0 >> 31) & __m1) \
+ + (((SItype) __m1 >> 31) & __m0)); \
+} while (0)
+#define smul_ppmm(xh, xl, m0, m1) \
+do { \
+ union {DItype __ll; \
+ struct {USItype __h, __l; } __i; \
+ } __xx; \
+ __asm__ ("mr %0,%3" \
+ : "=r" (__xx.__i.__h), \
+ "=r" (__xx.__i.__l) \
+ : "%1" (m0), \
+ "r" (m1)); \
+ (xh) = __xx.__i.__h; (xl) = __xx.__i.__l; \
+} while (0)
+#define sdiv_qrnnd(q, r, n1, n0, d) \
+do { \
+ union {DItype __ll; \
+ struct {USItype __h, __l; } __i; \
+ } __xx; \
+ __xx.__i.__h = n1; __xx.__i.__l = n0; \
+ __asm__ ("dr %0,%2" \
+ : "=r" (__xx.__ll) \
+ : "0" (__xx.__ll), "r" (d)); \
+ (q) = __xx.__i.__l; (r) = __xx.__i.__h; \
+} while (0)
+#endif
+
+/***************************************
+ ************** I386 *****************
+ ***************************************/
+#undef __i386__
+#if (defined(__i386__) || defined(__i486__)) && W_TYPE_SIZE == 32
+#define add_ssaaaa(sh, sl, ah, al, bh, bl) \
+ __asm__ ("addl %5,%1\n" \
+ "adcl %3,%0" \
+ : "=r" (sh), \
+ "=&r" (sl) \
+ : "%0" ((USItype)(ah)), \
+ "g" ((USItype)(bh)), \
+ "%1" ((USItype)(al)), \
+ "g" ((USItype)(bl)))
+#define sub_ddmmss(sh, sl, ah, al, bh, bl) \
+ __asm__ ("subl %5,%1\n" \
+ "sbbl %3,%0" \
+ : "=r" (sh), \
+ "=&r" (sl) \
+ : "0" ((USItype)(ah)), \
+ "g" ((USItype)(bh)), \
+ "1" ((USItype)(al)), \
+ "g" ((USItype)(bl)))
+#define umul_ppmm(w1, w0, u, v) \
+ __asm__ ("mull %3" \
+ : "=a" (w0), \
+ "=d" (w1) \
+ : "%0" ((USItype)(u)), \
+ "rm" ((USItype)(v)))
+#define udiv_qrnnd(q, r, n1, n0, d) \
+ __asm__ ("divl %4" \
+ : "=a" (q), \
+ "=d" (r) \
+ : "0" ((USItype)(n0)), \
+ "1" ((USItype)(n1)), \
+ "rm" ((USItype)(d)))
+#ifndef UMUL_TIME
+#define UMUL_TIME 40
+#endif
+#ifndef UDIV_TIME
+#define UDIV_TIME 40
+#endif
+#endif /* 80x86 */
+
+/***************************************
+ ************** I860 *****************
+ ***************************************/
+#if defined(__i860__) && W_TYPE_SIZE == 32
+#define rshift_rhlc(r, h, l, c) \
+ __asm__ ("shr %3,r0,r0\n" \
+ "shrd %1,%2,%0" \
+ "=r" (r) : "r" (h), "r" (l), "rn" (c))
+#endif /* i860 */
+
+/***************************************
+ ************** I960 *****************
+ ***************************************/
+#if defined(__i960__) && W_TYPE_SIZE == 32
+#define add_ssaaaa(sh, sl, ah, al, bh, bl) \
+ __asm__ ("cmpo 1,0\n" \
+ "addc %5,%4,%1\n" \
+ "addc %3,%2,%0" \
+ : "=r" ((USItype)(sh)), \
+ "=&r" ((USItype)(sl)) \
+ : "%dI" ((USItype)(ah)), \
+ "dI" ((USItype)(bh)), \
+ "%dI" ((USItype)(al)), \
+ "dI" ((USItype)(bl)))
+#define sub_ddmmss(sh, sl, ah, al, bh, bl) \
+ __asm__ ("cmpo 0,0\n" \
+ "subc %5,%4,%1\n" \
+ "subc %3,%2,%0" \
+ : "=r" ((USItype)(sh)), \
+ "=&r" ((USItype)(sl)) \
+ : "dI" ((USItype)(ah)), \
+ "dI" ((USItype)(bh)), \
+ "dI" ((USItype)(al)), \
+ "dI" ((USItype)(bl)))
+#define umul_ppmm(w1, w0, u, v) \
+ ({union {UDItype __ll; \
+ struct {USItype __l, __h; } __i; \
+ } __xx; \
+ __asm__ ("emul %2,%1,%0" \
+ : "=d" (__xx.__ll) \
+ : "%dI" ((USItype)(u)), \
+ "dI" ((USItype)(v))); \
+ (w1) = __xx.__i.__h; (w0) = __xx.__i.__l; })
+#define __umulsidi3(u, v) \
+ ({UDItype __w; \
+ __asm__ ("emul %2,%1,%0" \
+ : "=d" (__w) \
+ : "%dI" ((USItype)(u)), \
+ "dI" ((USItype)(v))); \
+ __w; })
+#define udiv_qrnnd(q, r, nh, nl, d) \
+do { \
+ union {UDItype __ll; \
+ struct {USItype __l, __h; } __i; \
+ } __nn; \
+ __nn.__i.__h = (nh); __nn.__i.__l = (nl); \
+ __asm__ ("ediv %d,%n,%0" \
+ : "=d" (__rq.__ll) \
+ : "dI" (__nn.__ll), \
+ "dI" ((USItype)(d))); \
+ (r) = __rq.__i.__l; (q) = __rq.__i.__h; \
+} while (0)
+#if defined(__i960mx) /* what is the proper symbol to test??? */
+#define rshift_rhlc(r, h, l, c) \
+do { \
+ union {UDItype __ll; \
+ struct {USItype __l, __h; } __i; \
+ } __nn; \
+ __nn.__i.__h = (h); __nn.__i.__l = (l); \
+ __asm__ ("shre %2,%1,%0" \
+ : "=d" (r) : "dI" (__nn.__ll), "dI" (c)); \
+}
+#endif /* i960mx */
+#endif /* i960 */
+
+/***************************************
+ ************** 68000 ****************
+ ***************************************/
+#if (defined(__mc68000__) || defined(__mc68020__) || defined(__NeXT__) || defined(mc68020)) && W_TYPE_SIZE == 32
+#define add_ssaaaa(sh, sl, ah, al, bh, bl) \
+ __asm__ ("add%.l %5,%1\n" \
+ "addx%.l %3,%0" \
+ : "=d" ((USItype)(sh)), \
+ "=&d" ((USItype)(sl)) \
+ : "%0" ((USItype)(ah)), \
+ "d" ((USItype)(bh)), \
+ "%1" ((USItype)(al)), \
+ "g" ((USItype)(bl)))
+#define sub_ddmmss(sh, sl, ah, al, bh, bl) \
+ __asm__ ("sub%.l %5,%1\n" \
+ "subx%.l %3,%0" \
+ : "=d" ((USItype)(sh)), \
+ "=&d" ((USItype)(sl)) \
+ : "0" ((USItype)(ah)), \
+ "d" ((USItype)(bh)), \
+ "1" ((USItype)(al)), \
+ "g" ((USItype)(bl)))
+#if (defined(__mc68020__) || defined(__NeXT__) || defined(mc68020))
+#define umul_ppmm(w1, w0, u, v) \
+ __asm__ ("mulu%.l %3,%1:%0" \
+ : "=d" ((USItype)(w0)), \
+ "=d" ((USItype)(w1)) \
+ : "%0" ((USItype)(u)), \
+ "dmi" ((USItype)(v)))
+#define UMUL_TIME 45
+#define udiv_qrnnd(q, r, n1, n0, d) \
+ __asm__ ("divu%.l %4,%1:%0" \
+ : "=d" ((USItype)(q)), \
+ "=d" ((USItype)(r)) \
+ : "0" ((USItype)(n0)), \
+ "1" ((USItype)(n1)), \
+ "dmi" ((USItype)(d)))
+#define UDIV_TIME 90
+#define sdiv_qrnnd(q, r, n1, n0, d) \
+ __asm__ ("divs%.l %4,%1:%0" \
+ : "=d" ((USItype)(q)), \
+ "=d" ((USItype)(r)) \
+ : "0" ((USItype)(n0)), \
+ "1" ((USItype)(n1)), \
+ "dmi" ((USItype)(d)))
+#else /* not mc68020 */
+#define umul_ppmm(xh, xl, a, b) \
+do { USItype __umul_tmp1, __umul_tmp2; \
+ __asm__ ("| Inlined umul_ppmm\n" \
+ "move%.l %5,%3\n" \
+ "move%.l %2,%0\n" \
+ "move%.w %3,%1\n" \
+ "swap %3\n" \
+ "swap %0\n" \
+ "mulu %2,%1\n" \
+ "mulu %3,%0\n" \
+ "mulu %2,%3\n" \
+ "swap %2\n" \
+ "mulu %5,%2\n" \
+ "add%.l %3,%2\n" \
+ "jcc 1f\n" \
+ "add%.l %#0x10000,%0\n" \
+ "1: move%.l %2,%3\n" \
+ "clr%.w %2\n" \
+ "swap %2\n" \
+ "swap %3\n" \
+ "clr%.w %3\n" \
+ "add%.l %3,%1\n" \
+ "addx%.l %2,%0\n" \
+ "| End inlined umul_ppmm" \
+ : "=&d" ((USItype)(xh)), "=&d" ((USItype)(xl)), \
+ "=d" (__umul_tmp1), "=&d" (__umul_tmp2) \
+ : "%2" ((USItype)(a)), "d" ((USItype)(b))); \
+} while (0)
+#define UMUL_TIME 100
+#define UDIV_TIME 400
+#endif /* not mc68020 */
+#endif /* mc68000 */
+
+/***************************************
+ ************** 88000 ****************
+ ***************************************/
+#if defined(__m88000__) && W_TYPE_SIZE == 32
+#define add_ssaaaa(sh, sl, ah, al, bh, bl) \
+ __asm__ ("addu.co %1,%r4,%r5\n" \
+ "addu.ci %0,%r2,%r3" \
+ : "=r" ((USItype)(sh)), \
+ "=&r" ((USItype)(sl)) \
+ : "%rJ" ((USItype)(ah)), \
+ "rJ" ((USItype)(bh)), \
+ "%rJ" ((USItype)(al)), \
+ "rJ" ((USItype)(bl)))
+#define sub_ddmmss(sh, sl, ah, al, bh, bl) \
+ __asm__ ("subu.co %1,%r4,%r5\n" \
+ "subu.ci %0,%r2,%r3" \
+ : "=r" ((USItype)(sh)), \
+ "=&r" ((USItype)(sl)) \
+ : "rJ" ((USItype)(ah)), \
+ "rJ" ((USItype)(bh)), \
+ "rJ" ((USItype)(al)), \
+ "rJ" ((USItype)(bl)))
+#if defined(__m88110__)
+#define umul_ppmm(wh, wl, u, v) \
+do { \
+ union {UDItype __ll; \
+ struct {USItype __h, __l; } __i; \
+ } __x; \
+ __asm__ ("mulu.d %0,%1,%2" : "=r" (__x.__ll) : "r" (u), "r" (v)); \
+ (wh) = __x.__i.__h; \
+ (wl) = __x.__i.__l; \
+} while (0)
+#define udiv_qrnnd(q, r, n1, n0, d) \
+ ({union {UDItype __ll; \
+ struct {USItype __h, __l; } __i; \
+ } __x, __q; \
+ __x.__i.__h = (n1); __x.__i.__l = (n0); \
+ __asm__ ("divu.d %0,%1,%2" \
+ : "=r" (__q.__ll) : "r" (__x.__ll), "r" (d)); \
+ (r) = (n0) - __q.__l * (d); (q) = __q.__l; })
+#define UMUL_TIME 5
+#define UDIV_TIME 25
+#else
+#define UMUL_TIME 17
+#define UDIV_TIME 150
+#endif /* __m88110__ */
+#endif /* __m88000__ */
+
+/***************************************
+ ************** MIPS *****************
+ ***************************************/
+#if defined(__mips__) && W_TYPE_SIZE == 32
+#define umul_ppmm(w1, w0, u, v) \
+do { \
+ UDItype __ll = (UDItype)(u) * (v); \
+ w1 = __ll >> 32; \
+ w0 = __ll; \
+} while (0)
+#define UMUL_TIME 10
+#define UDIV_TIME 100
+#endif /* __mips__ */
+
+/***************************************
+ ************** MIPS/64 **************
+ ***************************************/
+#if (defined(__mips) && __mips >= 3) && W_TYPE_SIZE == 64
+#if defined(__mips_isa_rev) && __mips_isa_rev >= 6 && defined(CONFIG_CC_IS_GCC)
+/*
+ * GCC ends up emitting a __multi3 intrinsic call for MIPS64r6 with the plain C
+ * code below, so we special case MIPS64r6 until the compiler can do better.
+ */
+#define umul_ppmm(w1, w0, u, v) \
+do { \
+ __asm__ ("dmulu %0,%1,%2" \
+ : "=d" ((UDItype)(w0)) \
+ : "d" ((UDItype)(u)), \
+ "d" ((UDItype)(v))); \
+ __asm__ ("dmuhu %0,%1,%2" \
+ : "=d" ((UDItype)(w1)) \
+ : "d" ((UDItype)(u)), \
+ "d" ((UDItype)(v))); \
+} while (0)
+#else
+#define umul_ppmm(w1, w0, u, v) \
+do { \
+ typedef unsigned int __ll_UTItype __attribute__((mode(TI))); \
+ __ll_UTItype __ll = (__ll_UTItype)(u) * (v); \
+ w1 = __ll >> 64; \
+ w0 = __ll; \
+} while (0)
+#endif
+#define UMUL_TIME 20
+#define UDIV_TIME 140
+#endif /* __mips__ */
+
+/***************************************
+ ************** 32000 ****************
+ ***************************************/
+#if defined(__ns32000__) && W_TYPE_SIZE == 32
+#define umul_ppmm(w1, w0, u, v) \
+ ({union {UDItype __ll; \
+ struct {USItype __l, __h; } __i; \
+ } __xx; \
+ __asm__ ("meid %2,%0" \
+ : "=g" (__xx.__ll) \
+ : "%0" ((USItype)(u)), \
+ "g" ((USItype)(v))); \
+ (w1) = __xx.__i.__h; (w0) = __xx.__i.__l; })
+#define __umulsidi3(u, v) \
+ ({UDItype __w; \
+ __asm__ ("meid %2,%0" \
+ : "=g" (__w) \
+ : "%0" ((USItype)(u)), \
+ "g" ((USItype)(v))); \
+ __w; })
+#define udiv_qrnnd(q, r, n1, n0, d) \
+ ({union {UDItype __ll; \
+ struct {USItype __l, __h; } __i; \
+ } __xx; \
+ __xx.__i.__h = (n1); __xx.__i.__l = (n0); \
+ __asm__ ("deid %2,%0" \
+ : "=g" (__xx.__ll) \
+ : "0" (__xx.__ll), \
+ "g" ((USItype)(d))); \
+ (r) = __xx.__i.__l; (q) = __xx.__i.__h; })
+#endif /* __ns32000__ */
+
+/***************************************
+ ************** PPC ******************
+ ***************************************/
+#if (defined(_ARCH_PPC) || defined(_IBMR2)) && W_TYPE_SIZE == 32
+#define add_ssaaaa(sh, sl, ah, al, bh, bl) \
+do { \
+ if (__builtin_constant_p(bh) && (bh) == 0) \
+ __asm__ ("{a%I4|add%I4c} %1,%3,%4\n\t{aze|addze} %0,%2" \
+ : "=r" (sh), \
+ "=&r" (sl) \
+ : "%r" ((USItype)(ah)), \
+ "%r" ((USItype)(al)), \
+ "rI" ((USItype)(bl))); \
+ else if (__builtin_constant_p(bh) && (bh) == ~(USItype) 0) \
+ __asm__ ("{a%I4|add%I4c} %1,%3,%4\n\t{ame|addme} %0,%2" \
+ : "=r" (sh), \
+ "=&r" (sl) \
+ : "%r" ((USItype)(ah)), \
+ "%r" ((USItype)(al)), \
+ "rI" ((USItype)(bl))); \
+ else \
+ __asm__ ("{a%I5|add%I5c} %1,%4,%5\n\t{ae|adde} %0,%2,%3" \
+ : "=r" (sh), \
+ "=&r" (sl) \
+ : "%r" ((USItype)(ah)), \
+ "r" ((USItype)(bh)), \
+ "%r" ((USItype)(al)), \
+ "rI" ((USItype)(bl))); \
+} while (0)
+#define sub_ddmmss(sh, sl, ah, al, bh, bl) \
+do { \
+ if (__builtin_constant_p(ah) && (ah) == 0) \
+ __asm__ ("{sf%I3|subf%I3c} %1,%4,%3\n\t{sfze|subfze} %0,%2" \
+ : "=r" (sh), \
+ "=&r" (sl) \
+ : "r" ((USItype)(bh)), \
+ "rI" ((USItype)(al)), \
+ "r" ((USItype)(bl))); \
+ else if (__builtin_constant_p(ah) && (ah) == ~(USItype) 0) \
+ __asm__ ("{sf%I3|subf%I3c} %1,%4,%3\n\t{sfme|subfme} %0,%2" \
+ : "=r" (sh), \
+ "=&r" (sl) \
+ : "r" ((USItype)(bh)), \
+ "rI" ((USItype)(al)), \
+ "r" ((USItype)(bl))); \
+ else if (__builtin_constant_p(bh) && (bh) == 0) \
+ __asm__ ("{sf%I3|subf%I3c} %1,%4,%3\n\t{ame|addme} %0,%2" \
+ : "=r" (sh), \
+ "=&r" (sl) \
+ : "r" ((USItype)(ah)), \
+ "rI" ((USItype)(al)), \
+ "r" ((USItype)(bl))); \
+ else if (__builtin_constant_p(bh) && (bh) == ~(USItype) 0) \
+ __asm__ ("{sf%I3|subf%I3c} %1,%4,%3\n\t{aze|addze} %0,%2" \
+ : "=r" (sh), \
+ "=&r" (sl) \
+ : "r" ((USItype)(ah)), \
+ "rI" ((USItype)(al)), \
+ "r" ((USItype)(bl))); \
+ else \
+ __asm__ ("{sf%I4|subf%I4c} %1,%5,%4\n\t{sfe|subfe} %0,%3,%2" \
+ : "=r" (sh), \
+ "=&r" (sl) \
+ : "r" ((USItype)(ah)), \
+ "r" ((USItype)(bh)), \
+ "rI" ((USItype)(al)), \
+ "r" ((USItype)(bl))); \
+} while (0)
+#if defined(_ARCH_PPC)
+#define umul_ppmm(ph, pl, m0, m1) \
+do { \
+ USItype __m0 = (m0), __m1 = (m1); \
+ __asm__ ("mulhwu %0,%1,%2" \
+ : "=r" (ph) \
+ : "%r" (__m0), \
+ "r" (__m1)); \
+ (pl) = __m0 * __m1; \
+} while (0)
+#define UMUL_TIME 15
+#define smul_ppmm(ph, pl, m0, m1) \
+do { \
+ SItype __m0 = (m0), __m1 = (m1); \
+ __asm__ ("mulhw %0,%1,%2" \
+ : "=r" ((SItype) ph) \
+ : "%r" (__m0), \
+ "r" (__m1)); \
+ (pl) = __m0 * __m1; \
+} while (0)
+#define SMUL_TIME 14
+#define UDIV_TIME 120
+#else
+#define umul_ppmm(xh, xl, m0, m1) \
+do { \
+ USItype __m0 = (m0), __m1 = (m1); \
+ __asm__ ("mul %0,%2,%3" \
+ : "=r" ((USItype)(xh)), \
+ "=q" ((USItype)(xl)) \
+ : "r" (__m0), \
+ "r" (__m1)); \
+ (xh) += ((((SItype) __m0 >> 31) & __m1) \
+ + (((SItype) __m1 >> 31) & __m0)); \
+} while (0)
+#define UMUL_TIME 8
+#define smul_ppmm(xh, xl, m0, m1) \
+ __asm__ ("mul %0,%2,%3" \
+ : "=r" ((SItype)(xh)), \
+ "=q" ((SItype)(xl)) \
+ : "r" (m0), \
+ "r" (m1))
+#define SMUL_TIME 4
+#define sdiv_qrnnd(q, r, nh, nl, d) \
+ __asm__ ("div %0,%2,%4" \
+ : "=r" ((SItype)(q)), "=q" ((SItype)(r)) \
+ : "r" ((SItype)(nh)), "1" ((SItype)(nl)), "r" ((SItype)(d)))
+#define UDIV_TIME 100
+#endif
+#endif /* Power architecture variants. */
+
+/***************************************
+ ************** PYR ******************
+ ***************************************/
+#if defined(__pyr__) && W_TYPE_SIZE == 32
+#define add_ssaaaa(sh, sl, ah, al, bh, bl) \
+ __asm__ ("addw %5,%1\n" \
+ "addwc %3,%0" \
+ : "=r" ((USItype)(sh)), \
+ "=&r" ((USItype)(sl)) \
+ : "%0" ((USItype)(ah)), \
+ "g" ((USItype)(bh)), \
+ "%1" ((USItype)(al)), \
+ "g" ((USItype)(bl)))
+#define sub_ddmmss(sh, sl, ah, al, bh, bl) \
+ __asm__ ("subw %5,%1\n" \
+ "subwb %3,%0" \
+ : "=r" ((USItype)(sh)), \
+ "=&r" ((USItype)(sl)) \
+ : "0" ((USItype)(ah)), \
+ "g" ((USItype)(bh)), \
+ "1" ((USItype)(al)), \
+ "g" ((USItype)(bl)))
+ /* This insn works on Pyramids with AP, XP, or MI CPUs, but not with SP. */
+#define umul_ppmm(w1, w0, u, v) \
+ ({union {UDItype __ll; \
+ struct {USItype __h, __l; } __i; \
+ } __xx; \
+ __asm__ ("movw %1,%R0\n" \
+ "uemul %2,%0" \
+ : "=&r" (__xx.__ll) \
+ : "g" ((USItype) (u)), \
+ "g" ((USItype)(v))); \
+ (w1) = __xx.__i.__h; (w0) = __xx.__i.__l; })
+#endif /* __pyr__ */
+
+/***************************************
+ ************** RT/ROMP **************
+ ***************************************/
+#if defined(__ibm032__) /* RT/ROMP */ && W_TYPE_SIZE == 32
+#define add_ssaaaa(sh, sl, ah, al, bh, bl) \
+ __asm__ ("a %1,%5\n" \
+ "ae %0,%3" \
+ : "=r" ((USItype)(sh)), \
+ "=&r" ((USItype)(sl)) \
+ : "%0" ((USItype)(ah)), \
+ "r" ((USItype)(bh)), \
+ "%1" ((USItype)(al)), \
+ "r" ((USItype)(bl)))
+#define sub_ddmmss(sh, sl, ah, al, bh, bl) \
+ __asm__ ("s %1,%5\n" \
+ "se %0,%3" \
+ : "=r" ((USItype)(sh)), \
+ "=&r" ((USItype)(sl)) \
+ : "0" ((USItype)(ah)), \
+ "r" ((USItype)(bh)), \
+ "1" ((USItype)(al)), \
+ "r" ((USItype)(bl)))
+#define umul_ppmm(ph, pl, m0, m1) \
+do { \
+ USItype __m0 = (m0), __m1 = (m1); \
+ __asm__ ( \
+ "s r2,r2\n" \
+ "mts r10,%2\n" \
+ "m r2,%3\n" \
+ "m r2,%3\n" \
+ "m r2,%3\n" \
+ "m r2,%3\n" \
+ "m r2,%3\n" \
+ "m r2,%3\n" \
+ "m r2,%3\n" \
+ "m r2,%3\n" \
+ "m r2,%3\n" \
+ "m r2,%3\n" \
+ "m r2,%3\n" \
+ "m r2,%3\n" \
+ "m r2,%3\n" \
+ "m r2,%3\n" \
+ "m r2,%3\n" \
+ "m r2,%3\n" \
+ "cas %0,r2,r0\n" \
+ "mfs r10,%1" \
+ : "=r" ((USItype)(ph)), \
+ "=r" ((USItype)(pl)) \
+ : "%r" (__m0), \
+ "r" (__m1) \
+ : "r2"); \
+ (ph) += ((((SItype) __m0 >> 31) & __m1) \
+ + (((SItype) __m1 >> 31) & __m0)); \
+} while (0)
+#define UMUL_TIME 20
+#define UDIV_TIME 200
+#endif /* RT/ROMP */
+
+/***************************************
+ ************** SH2 ******************
+ ***************************************/
+#if (defined(__sh2__) || defined(__sh3__) || defined(__SH4__)) \
+ && W_TYPE_SIZE == 32
+#define umul_ppmm(w1, w0, u, v) \
+ __asm__ ( \
+ "dmulu.l %2,%3\n" \
+ "sts macl,%1\n" \
+ "sts mach,%0" \
+ : "=r" ((USItype)(w1)), \
+ "=r" ((USItype)(w0)) \
+ : "r" ((USItype)(u)), \
+ "r" ((USItype)(v)) \
+ : "macl", "mach")
+#define UMUL_TIME 5
+#endif
+
+/***************************************
+ ************** SPARC ****************
+ ***************************************/
+#if defined(__sparc__) && W_TYPE_SIZE == 32
+#define add_ssaaaa(sh, sl, ah, al, bh, bl) \
+ __asm__ ("addcc %r4,%5,%1\n" \
+ "addx %r2,%3,%0" \
+ : "=r" ((USItype)(sh)), \
+ "=&r" ((USItype)(sl)) \
+ : "%rJ" ((USItype)(ah)), \
+ "rI" ((USItype)(bh)), \
+ "%rJ" ((USItype)(al)), \
+ "rI" ((USItype)(bl)) \
+ __CLOBBER_CC)
+#define sub_ddmmss(sh, sl, ah, al, bh, bl) \
+ __asm__ ("subcc %r4,%5,%1\n" \
+ "subx %r2,%3,%0" \
+ : "=r" ((USItype)(sh)), \
+ "=&r" ((USItype)(sl)) \
+ : "rJ" ((USItype)(ah)), \
+ "rI" ((USItype)(bh)), \
+ "rJ" ((USItype)(al)), \
+ "rI" ((USItype)(bl)) \
+ __CLOBBER_CC)
+#if defined(__sparc_v8__)
+/* Don't match immediate range because, 1) it is not often useful,
+ 2) the 'I' flag thinks of the range as a 13 bit signed interval,
+ while we want to match a 13 bit interval, sign extended to 32 bits,
+ but INTERPRETED AS UNSIGNED. */
+#define umul_ppmm(w1, w0, u, v) \
+ __asm__ ("umul %2,%3,%1;rd %%y,%0" \
+ : "=r" ((USItype)(w1)), \
+ "=r" ((USItype)(w0)) \
+ : "r" ((USItype)(u)), \
+ "r" ((USItype)(v)))
+#define UMUL_TIME 5
+#ifndef SUPERSPARC /* SuperSPARC's udiv only handles 53 bit dividends */
+#define udiv_qrnnd(q, r, n1, n0, d) \
+do { \
+ USItype __q; \
+ __asm__ ("mov %1,%%y;nop;nop;nop;udiv %2,%3,%0" \
+ : "=r" ((USItype)(__q)) \
+ : "r" ((USItype)(n1)), \
+ "r" ((USItype)(n0)), \
+ "r" ((USItype)(d))); \
+ (r) = (n0) - __q * (d); \
+ (q) = __q; \
+} while (0)
+#define UDIV_TIME 25
+#endif /* SUPERSPARC */
+#else /* ! __sparc_v8__ */
+#if defined(__sparclite__)
+/* This has hardware multiply but not divide. It also has two additional
+ instructions scan (ffs from high bit) and divscc. */
+#define umul_ppmm(w1, w0, u, v) \
+ __asm__ ("umul %2,%3,%1;rd %%y,%0" \
+ : "=r" ((USItype)(w1)), \
+ "=r" ((USItype)(w0)) \
+ : "r" ((USItype)(u)), \
+ "r" ((USItype)(v)))
+#define UMUL_TIME 5
+#define udiv_qrnnd(q, r, n1, n0, d) \
+ __asm__ ("! Inlined udiv_qrnnd\n" \
+ "wr %%g0,%2,%%y ! Not a delayed write for sparclite\n" \
+ "tst %%g0\n" \
+ "divscc %3,%4,%%g1\n" \
+ "divscc %%g1,%4,%%g1\n" \
+ "divscc %%g1,%4,%%g1\n" \
+ "divscc %%g1,%4,%%g1\n" \
+ "divscc %%g1,%4,%%g1\n" \
+ "divscc %%g1,%4,%%g1\n" \
+ "divscc %%g1,%4,%%g1\n" \
+ "divscc %%g1,%4,%%g1\n" \
+ "divscc %%g1,%4,%%g1\n" \
+ "divscc %%g1,%4,%%g1\n" \
+ "divscc %%g1,%4,%%g1\n" \
+ "divscc %%g1,%4,%%g1\n" \
+ "divscc %%g1,%4,%%g1\n" \
+ "divscc %%g1,%4,%%g1\n" \
+ "divscc %%g1,%4,%%g1\n" \
+ "divscc %%g1,%4,%%g1\n" \
+ "divscc %%g1,%4,%%g1\n" \
+ "divscc %%g1,%4,%%g1\n" \
+ "divscc %%g1,%4,%%g1\n" \
+ "divscc %%g1,%4,%%g1\n" \
+ "divscc %%g1,%4,%%g1\n" \
+ "divscc %%g1,%4,%%g1\n" \
+ "divscc %%g1,%4,%%g1\n" \
+ "divscc %%g1,%4,%%g1\n" \
+ "divscc %%g1,%4,%%g1\n" \
+ "divscc %%g1,%4,%%g1\n" \
+ "divscc %%g1,%4,%%g1\n" \
+ "divscc %%g1,%4,%%g1\n" \
+ "divscc %%g1,%4,%%g1\n" \
+ "divscc %%g1,%4,%%g1\n" \
+ "divscc %%g1,%4,%%g1\n" \
+ "divscc %%g1,%4,%0\n" \
+ "rd %%y,%1\n" \
+ "bl,a 1f\n" \
+ "add %1,%4,%1\n" \
+ "1: ! End of inline udiv_qrnnd" \
+ : "=r" ((USItype)(q)), \
+ "=r" ((USItype)(r)) \
+ : "r" ((USItype)(n1)), \
+ "r" ((USItype)(n0)), \
+ "rI" ((USItype)(d)) \
+ : "%g1" __AND_CLOBBER_CC)
+#define UDIV_TIME 37
+#endif /* __sparclite__ */
+#endif /* __sparc_v8__ */
+ /* Default to sparc v7 versions of umul_ppmm and udiv_qrnnd. */
+#ifndef umul_ppmm
+#define umul_ppmm(w1, w0, u, v) \
+ __asm__ ("! Inlined umul_ppmm\n" \
+ "wr %%g0,%2,%%y ! SPARC has 0-3 delay insn after a wr\n" \
+ "sra %3,31,%%g2 ! Don't move this insn\n" \
+ "and %2,%%g2,%%g2 ! Don't move this insn\n" \
+ "andcc %%g0,0,%%g1 ! Don't move this insn\n" \
+ "mulscc %%g1,%3,%%g1\n" \
+ "mulscc %%g1,%3,%%g1\n" \
+ "mulscc %%g1,%3,%%g1\n" \
+ "mulscc %%g1,%3,%%g1\n" \
+ "mulscc %%g1,%3,%%g1\n" \
+ "mulscc %%g1,%3,%%g1\n" \
+ "mulscc %%g1,%3,%%g1\n" \
+ "mulscc %%g1,%3,%%g1\n" \
+ "mulscc %%g1,%3,%%g1\n" \
+ "mulscc %%g1,%3,%%g1\n" \
+ "mulscc %%g1,%3,%%g1\n" \
+ "mulscc %%g1,%3,%%g1\n" \
+ "mulscc %%g1,%3,%%g1\n" \
+ "mulscc %%g1,%3,%%g1\n" \
+ "mulscc %%g1,%3,%%g1\n" \
+ "mulscc %%g1,%3,%%g1\n" \
+ "mulscc %%g1,%3,%%g1\n" \
+ "mulscc %%g1,%3,%%g1\n" \
+ "mulscc %%g1,%3,%%g1\n" \
+ "mulscc %%g1,%3,%%g1\n" \
+ "mulscc %%g1,%3,%%g1\n" \
+ "mulscc %%g1,%3,%%g1\n" \
+ "mulscc %%g1,%3,%%g1\n" \
+ "mulscc %%g1,%3,%%g1\n" \
+ "mulscc %%g1,%3,%%g1\n" \
+ "mulscc %%g1,%3,%%g1\n" \
+ "mulscc %%g1,%3,%%g1\n" \
+ "mulscc %%g1,%3,%%g1\n" \
+ "mulscc %%g1,%3,%%g1\n" \
+ "mulscc %%g1,%3,%%g1\n" \
+ "mulscc %%g1,%3,%%g1\n" \
+ "mulscc %%g1,%3,%%g1\n" \
+ "mulscc %%g1,0,%%g1\n" \
+ "add %%g1,%%g2,%0\n" \
+ "rd %%y,%1" \
+ : "=r" ((USItype)(w1)), \
+ "=r" ((USItype)(w0)) \
+ : "%rI" ((USItype)(u)), \
+ "r" ((USItype)(v)) \
+ : "%g1", "%g2" __AND_CLOBBER_CC)
+#define UMUL_TIME 39 /* 39 instructions */
+/* It's quite necessary to add this much assembler for the sparc.
+ The default udiv_qrnnd (in C) is more than 10 times slower! */
+#define udiv_qrnnd(q, r, n1, n0, d) \
+ __asm__ ("! Inlined udiv_qrnnd\n\t" \
+ "mov 32,%%g1\n\t" \
+ "subcc %1,%2,%%g0\n\t" \
+ "1: bcs 5f\n\t" \
+ "addxcc %0,%0,%0 ! shift n1n0 and a q-bit in lsb\n\t" \
+ "sub %1,%2,%1 ! this kills msb of n\n\t" \
+ "addx %1,%1,%1 ! so this can't give carry\n\t" \
+ "subcc %%g1,1,%%g1\n\t" \
+ "2: bne 1b\n\t" \
+ "subcc %1,%2,%%g0\n\t" \
+ "bcs 3f\n\t" \
+ "addxcc %0,%0,%0 ! shift n1n0 and a q-bit in lsb\n\t" \
+ "b 3f\n\t" \
+ "sub %1,%2,%1 ! this kills msb of n\n\t" \
+ "4: sub %1,%2,%1\n\t" \
+ "5: addxcc %1,%1,%1\n\t" \
+ "bcc 2b\n\t" \
+ "subcc %%g1,1,%%g1\n\t" \
+ "! Got carry from n. Subtract next step to cancel this carry.\n\t" \
+ "bne 4b\n\t" \
+ "addcc %0,%0,%0 ! shift n1n0 and a 0-bit in lsb\n\t" \
+ "sub %1,%2,%1\n\t" \
+ "3: xnor %0,0,%0\n\t" \
+ "! End of inline udiv_qrnnd\n" \
+ : "=&r" ((USItype)(q)), \
+ "=&r" ((USItype)(r)) \
+ : "r" ((USItype)(d)), \
+ "1" ((USItype)(n1)), \
+ "0" ((USItype)(n0)) : "%g1", "cc")
+#define UDIV_TIME (3+7*32) /* 7 instructions/iteration. 32 iterations. */
+#endif
+#endif /* __sparc__ */
+
+/***************************************
+ ************** VAX ******************
+ ***************************************/
+#if defined(__vax__) && W_TYPE_SIZE == 32
+#define add_ssaaaa(sh, sl, ah, al, bh, bl) \
+ __asm__ ("addl2 %5,%1\n" \
+ "adwc %3,%0" \
+ : "=g" ((USItype)(sh)), \
+ "=&g" ((USItype)(sl)) \
+ : "%0" ((USItype)(ah)), \
+ "g" ((USItype)(bh)), \
+ "%1" ((USItype)(al)), \
+ "g" ((USItype)(bl)))
+#define sub_ddmmss(sh, sl, ah, al, bh, bl) \
+ __asm__ ("subl2 %5,%1\n" \
+ "sbwc %3,%0" \
+ : "=g" ((USItype)(sh)), \
+ "=&g" ((USItype)(sl)) \
+ : "0" ((USItype)(ah)), \
+ "g" ((USItype)(bh)), \
+ "1" ((USItype)(al)), \
+ "g" ((USItype)(bl)))
+#define umul_ppmm(xh, xl, m0, m1) \
+do { \
+ union {UDItype __ll; \
+ struct {USItype __l, __h; } __i; \
+ } __xx; \
+ USItype __m0 = (m0), __m1 = (m1); \
+ __asm__ ("emul %1,%2,$0,%0" \
+ : "=g" (__xx.__ll) \
+ : "g" (__m0), \
+ "g" (__m1)); \
+ (xh) = __xx.__i.__h; (xl) = __xx.__i.__l; \
+ (xh) += ((((SItype) __m0 >> 31) & __m1) \
+ + (((SItype) __m1 >> 31) & __m0)); \
+} while (0)
+#define sdiv_qrnnd(q, r, n1, n0, d) \
+do { \
+ union {DItype __ll; \
+ struct {SItype __l, __h; } __i; \
+ } __xx; \
+ __xx.__i.__h = n1; __xx.__i.__l = n0; \
+ __asm__ ("ediv %3,%2,%0,%1" \
+ : "=g" (q), "=g" (r) \
+ : "g" (__xx.__ll), "g" (d)); \
+} while (0)
+#endif /* __vax__ */
+
+/***************************************
+ ************** Z8000 ****************
+ ***************************************/
+#if defined(__z8000__) && W_TYPE_SIZE == 16
+#define add_ssaaaa(sh, sl, ah, al, bh, bl) \
+ __asm__ ("add %H1,%H5\n\tadc %H0,%H3" \
+ : "=r" ((unsigned int)(sh)), \
+ "=&r" ((unsigned int)(sl)) \
+ : "%0" ((unsigned int)(ah)), \
+ "r" ((unsigned int)(bh)), \
+ "%1" ((unsigned int)(al)), \
+ "rQR" ((unsigned int)(bl)))
+#define sub_ddmmss(sh, sl, ah, al, bh, bl) \
+ __asm__ ("sub %H1,%H5\n\tsbc %H0,%H3" \
+ : "=r" ((unsigned int)(sh)), \
+ "=&r" ((unsigned int)(sl)) \
+ : "0" ((unsigned int)(ah)), \
+ "r" ((unsigned int)(bh)), \
+ "1" ((unsigned int)(al)), \
+ "rQR" ((unsigned int)(bl)))
+#define umul_ppmm(xh, xl, m0, m1) \
+do { \
+ union {long int __ll; \
+ struct {unsigned int __h, __l; } __i; \
+ } __xx; \
+ unsigned int __m0 = (m0), __m1 = (m1); \
+ __asm__ ("mult %S0,%H3" \
+ : "=r" (__xx.__i.__h), \
+ "=r" (__xx.__i.__l) \
+ : "%1" (__m0), \
+ "rQR" (__m1)); \
+ (xh) = __xx.__i.__h; (xl) = __xx.__i.__l; \
+ (xh) += ((((signed int) __m0 >> 15) & __m1) \
+ + (((signed int) __m1 >> 15) & __m0)); \
+} while (0)
+#endif /* __z8000__ */
+
+#endif /* __GNUC__ */
+
+/***************************************
+ *********** Generic Versions ********
+ ***************************************/
+#if !defined(umul_ppmm) && defined(__umulsidi3)
+#define umul_ppmm(ph, pl, m0, m1) \
+{ \
+ UDWtype __ll = __umulsidi3(m0, m1); \
+ ph = (UWtype) (__ll >> W_TYPE_SIZE); \
+ pl = (UWtype) __ll; \
+}
+#endif
+
+#if !defined(__umulsidi3)
+#define __umulsidi3(u, v) \
+ ({UWtype __hi, __lo; \
+ umul_ppmm(__hi, __lo, u, v); \
+ ((UDWtype) __hi << W_TYPE_SIZE) | __lo; })
+#endif
+
+ /* If this machine has no inline assembler, use C macros. */
+
+#if !defined(add_ssaaaa)
+#define add_ssaaaa(sh, sl, ah, al, bh, bl) \
+do { \
+ UWtype __x; \
+ __x = (al) + (bl); \
+ (sh) = (ah) + (bh) + (__x < (al)); \
+ (sl) = __x; \
+} while (0)
+#endif
+
+#if !defined(sub_ddmmss)
+#define sub_ddmmss(sh, sl, ah, al, bh, bl) \
+do { \
+ UWtype __x; \
+ __x = (al) - (bl); \
+ (sh) = (ah) - (bh) - (__x > (al)); \
+ (sl) = __x; \
+} while (0)
+#endif
+
+#if !defined(umul_ppmm)
+#define umul_ppmm(w1, w0, u, v) \
+do { \
+ UWtype __x0, __x1, __x2, __x3; \
+ UHWtype __ul, __vl, __uh, __vh; \
+ UWtype __u = (u), __v = (v); \
+ \
+ __ul = __ll_lowpart(__u); \
+ __uh = __ll_highpart(__u); \
+ __vl = __ll_lowpart(__v); \
+ __vh = __ll_highpart(__v); \
+ \
+ __x0 = (UWtype) __ul * __vl; \
+ __x1 = (UWtype) __ul * __vh; \
+ __x2 = (UWtype) __uh * __vl; \
+ __x3 = (UWtype) __uh * __vh; \
+ \
+ __x1 += __ll_highpart(__x0);/* this can't give carry */ \
+ __x1 += __x2; /* but this indeed can */ \
+ if (__x1 < __x2) /* did we get it? */ \
+ __x3 += __ll_B; /* yes, add it in the proper pos. */ \
+ \
+ (w1) = __x3 + __ll_highpart(__x1); \
+ (w0) = (__ll_lowpart(__x1) << W_TYPE_SIZE/2) + __ll_lowpart(__x0); \
+} while (0)
+#endif
+
+#if !defined(umul_ppmm)
+#define smul_ppmm(w1, w0, u, v) \
+do { \
+ UWtype __w1; \
+ UWtype __m0 = (u), __m1 = (v); \
+ umul_ppmm(__w1, w0, __m0, __m1); \
+ (w1) = __w1 - (-(__m0 >> (W_TYPE_SIZE - 1)) & __m1) \
+ - (-(__m1 >> (W_TYPE_SIZE - 1)) & __m0); \
+} while (0)
+#endif
+
+ /* Define this unconditionally, so it can be used for debugging. */
+#define __udiv_qrnnd_c(q, r, n1, n0, d) \
+do { \
+ UWtype __d1, __d0, __q1, __q0, __r1, __r0, __m; \
+ __d1 = __ll_highpart(d); \
+ __d0 = __ll_lowpart(d); \
+ \
+ __r1 = (n1) % __d1; \
+ __q1 = (n1) / __d1; \
+ __m = (UWtype) __q1 * __d0; \
+ __r1 = __r1 * __ll_B | __ll_highpart(n0); \
+ if (__r1 < __m) { \
+ __q1--, __r1 += (d); \
+ if (__r1 >= (d)) /* i.e. we didn't get carry when adding to __r1 */ \
+ if (__r1 < __m) \
+ __q1--, __r1 += (d); \
+ } \
+ __r1 -= __m; \
+ \
+ __r0 = __r1 % __d1; \
+ __q0 = __r1 / __d1; \
+ __m = (UWtype) __q0 * __d0; \
+ __r0 = __r0 * __ll_B | __ll_lowpart(n0); \
+ if (__r0 < __m) { \
+ __q0--, __r0 += (d); \
+ if (__r0 >= (d)) \
+ if (__r0 < __m) \
+ __q0--, __r0 += (d); \
+ } \
+ __r0 -= __m; \
+ \
+ (q) = (UWtype) __q1 * __ll_B | __q0; \
+ (r) = __r0; \
+} while (0)
+
+/* If the processor has no udiv_qrnnd but sdiv_qrnnd, go through
+ __udiv_w_sdiv (defined in libgcc or elsewhere). */
+#if !defined(udiv_qrnnd) && defined(sdiv_qrnnd)
+#define udiv_qrnnd(q, r, nh, nl, d) \
+do { \
+ UWtype __r; \
+ (q) = __MPN(udiv_w_sdiv) (&__r, nh, nl, d); \
+ (r) = __r; \
+} while (0)
+#endif
+
+ /* If udiv_qrnnd was not defined for this processor, use __udiv_qrnnd_c. */
+#if !defined(udiv_qrnnd)
+#define UDIV_NEEDS_NORMALIZATION 1
+#define udiv_qrnnd __udiv_qrnnd_c
+#endif
+
+#ifndef UDIV_NEEDS_NORMALIZATION
+#define UDIV_NEEDS_NORMALIZATION 0
+#endif
diff --git a/lib/mpi/mpi-add.c b/lib/mpi/mpi-add.c
new file mode 100644
index 000000000..9056fc516
--- /dev/null
+++ b/lib/mpi/mpi-add.c
@@ -0,0 +1,155 @@
+/* mpi-add.c - MPI functions
+ * Copyright (C) 1994, 1996, 1998, 2001, 2002,
+ * 2003 Free Software Foundation, Inc.
+ *
+ * This file is part of Libgcrypt.
+ *
+ * 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.
+ */
+
+#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.
+ */
+void mpi_add_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)
+ mpi_resize(w, wsize);
+
+ /* 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;
+}
+
+
+void 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;
+ RESIZE_IF_NEEDED(w, wsize);
+ /* 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;
+ RESIZE_IF_NEEDED(w, wsize);
+ /* 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;
+}
+EXPORT_SYMBOL_GPL(mpi_add);
+
+void mpi_sub(MPI w, MPI u, MPI v)
+{
+ MPI vv = mpi_copy(v);
+ vv->sign = !vv->sign;
+ mpi_add(w, u, vv);
+ mpi_free(vv);
+}
+EXPORT_SYMBOL_GPL(mpi_sub);
+
+void mpi_addm(MPI w, MPI u, MPI v, MPI m)
+{
+ mpi_add(w, u, v);
+ mpi_mod(w, w, m);
+}
+EXPORT_SYMBOL_GPL(mpi_addm);
+
+void mpi_subm(MPI w, MPI u, MPI v, MPI m)
+{
+ mpi_sub(w, u, v);
+ mpi_mod(w, w, m);
+}
+EXPORT_SYMBOL_GPL(mpi_subm);
diff --git a/lib/mpi/mpi-bit.c b/lib/mpi/mpi-bit.c
new file mode 100644
index 000000000..070ba784c
--- /dev/null
+++ b/lib/mpi/mpi-bit.c
@@ -0,0 +1,308 @@
+/* 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);
+}
diff --git a/lib/mpi/mpi-cmp.c b/lib/mpi/mpi-cmp.c
new file mode 100644
index 000000000..0835b6213
--- /dev/null
+++ b/lib/mpi/mpi-cmp.c
@@ -0,0 +1,98 @@
+/* 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 == 0) {
+ if (v == 0)
+ return 0;
+ else
+ return -1;
+ }
+ 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;
+}
+EXPORT_SYMBOL_GPL(mpi_cmp_ui);
+
+static int do_mpi_cmp(MPI u, MPI v, int absmode)
+{
+ mpi_size_t usize;
+ mpi_size_t vsize;
+ int usign;
+ int vsign;
+ int cmp;
+
+ mpi_normalize(u);
+ mpi_normalize(v);
+
+ usize = u->nlimbs;
+ vsize = v->nlimbs;
+ usign = absmode ? 0 : u->sign;
+ vsign = absmode ? 0 : v->sign;
+
+ /* Compare sign bits. */
+
+ if (!usign && vsign)
+ return 1;
+ if (usign && !vsign)
+ return -1;
+
+ /* U and V are either both positive or both negative. */
+
+ if (usize != vsize && !usign && !vsign)
+ return usize - vsize;
+ if (usize != vsize && usign && vsign)
+ return vsize + usize;
+ if (!usize)
+ return 0;
+ cmp = mpihelp_cmp(u->d, v->d, usize);
+ if (!cmp)
+ return 0;
+ if ((cmp < 0?1:0) == (usign?1:0))
+ return 1;
+
+ return -1;
+}
+
+int mpi_cmp(MPI u, MPI v)
+{
+ return do_mpi_cmp(u, v, 0);
+}
+EXPORT_SYMBOL_GPL(mpi_cmp);
+
+int mpi_cmpabs(MPI u, MPI v)
+{
+ return do_mpi_cmp(u, v, 1);
+}
+EXPORT_SYMBOL_GPL(mpi_cmpabs);
diff --git a/lib/mpi/mpi-div.c b/lib/mpi/mpi-div.c
new file mode 100644
index 000000000..45beab8b9
--- /dev/null
+++ b/lib/mpi/mpi-div.c
@@ -0,0 +1,234 @@
+/* mpi-div.c - MPI functions
+ * Copyright (C) 1994, 1996, 1998, 2001, 2002,
+ * 2003 Free Software Foundation, Inc.
+ *
+ * This file is part of Libgcrypt.
+ *
+ * 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.
+ */
+
+#include "mpi-internal.h"
+#include "longlong.h"
+
+void mpi_tdiv_qr(MPI quot, MPI rem, MPI num, MPI den);
+void mpi_fdiv_qr(MPI quot, MPI rem, MPI dividend, MPI divisor);
+
+void mpi_fdiv_r(MPI rem, MPI dividend, MPI divisor)
+{
+ 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) {
+ temp_divisor = mpi_copy(divisor);
+ divisor = temp_divisor;
+ }
+
+ mpi_tdiv_r(rem, dividend, divisor);
+
+ if (((divisor_sign?1:0) ^ (dividend->sign?1:0)) && rem->nlimbs)
+ mpi_add(rem, rem, divisor);
+
+ if (temp_divisor)
+ mpi_free(temp_divisor);
+}
+
+void mpi_fdiv_q(MPI quot, MPI dividend, MPI divisor)
+{
+ MPI tmp = mpi_alloc(mpi_get_nlimbs(quot));
+ mpi_fdiv_qr(quot, tmp, dividend, divisor);
+ mpi_free(tmp);
+}
+
+void 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) {
+ temp_divisor = mpi_copy(divisor);
+ divisor = temp_divisor;
+ }
+
+ mpi_tdiv_qr(quot, rem, dividend, divisor);
+
+ if ((divisor_sign ^ dividend->sign) && rem->nlimbs) {
+ mpi_sub_ui(quot, quot, 1);
+ mpi_add(rem, rem, divisor);
+ }
+
+ if (temp_divisor)
+ mpi_free(temp_divisor);
+}
+
+/* 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.
+ */
+
+void mpi_tdiv_r(MPI rem, MPI num, MPI den)
+{
+ mpi_tdiv_qr(NULL, rem, num, den);
+}
+
+void mpi_tdiv_qr(MPI quot, MPI rem, MPI num, MPI den)
+{
+ 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 int normalization_steps;
+ mpi_limb_t q_limb;
+ mpi_ptr_t marker[5];
+ int markidx = 0;
+
+ /* 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;
+ mpi_resize(rem, rsize);
+
+ 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;
+ }
+
+ if (quot)
+ mpi_resize(quot, qsize);
+
+ /* 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;
+ }
+
+
+ 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);
+ MPN_COPY(np, qp, nsize);
+ }
+ } else /* Put quotient at top of remainder. */
+ qp = rp + dsize;
+
+ normalization_steps = count_leading_zeros(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);
+ 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);
+ 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;
+ while (markidx) {
+ markidx--;
+ mpi_free_limb_space(marker[markidx]);
+ }
+}
diff --git a/lib/mpi/mpi-inline.h b/lib/mpi/mpi-inline.h
new file mode 100644
index 000000000..980b6b940
--- /dev/null
+++ b/lib/mpi/mpi-inline.h
@@ -0,0 +1,109 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/* mpi-inline.h - Internal to the Multi Precision Integers
+ * Copyright (C) 1994, 1996, 1998, 1999 Free Software Foundation, Inc.
+ *
+ * This file is part of GnuPG.
+ *
+ * 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.
+ */
+
+#ifndef G10_MPI_INLINE_H
+#define G10_MPI_INLINE_H
+
+#ifndef G10_MPI_INLINE_DECL
+#define G10_MPI_INLINE_DECL static inline
+#endif
+
+G10_MPI_INLINE_DECL mpi_limb_t
+mpihelp_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 x;
+
+ x = *s1_ptr++;
+ s2_limb += x;
+ *res_ptr++ = s2_limb;
+ if (s2_limb < x) { /* sum is less than the left operand: handle carry */
+ while (--s1_size) {
+ x = *s1_ptr++ + 1; /* add carry */
+ *res_ptr++ = x; /* and store */
+ if (x) /* not 0 (no overflow): we can stop */
+ goto leave;
+ }
+ return 1; /* return carry (size of s1 to small) */
+ }
+
+leave:
+ if (res_ptr != s1_ptr) { /* not the same variable */
+ mpi_size_t i; /* copy the rest */
+ for (i = 0; i < s1_size - 1; i++)
+ res_ptr[i] = s1_ptr[i];
+ }
+ return 0; /* no carry */
+}
+
+G10_MPI_INLINE_DECL mpi_limb_t
+mpihelp_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)
+{
+ mpi_limb_t cy = 0;
+
+ if (s2_size)
+ cy = mpihelp_add_n(res_ptr, s1_ptr, s2_ptr, s2_size);
+
+ if (s1_size - s2_size)
+ cy = mpihelp_add_1(res_ptr + s2_size, s1_ptr + s2_size,
+ s1_size - s2_size, cy);
+ return cy;
+}
+
+G10_MPI_INLINE_DECL mpi_limb_t
+mpihelp_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 x;
+
+ x = *s1_ptr++;
+ s2_limb = x - s2_limb;
+ *res_ptr++ = s2_limb;
+ if (s2_limb > x) {
+ while (--s1_size) {
+ x = *s1_ptr++;
+ *res_ptr++ = x - 1;
+ if (x)
+ goto leave;
+ }
+ return 1;
+ }
+
+leave:
+ if (res_ptr != s1_ptr) {
+ mpi_size_t i;
+ for (i = 0; i < s1_size - 1; i++)
+ res_ptr[i] = s1_ptr[i];
+ }
+ return 0;
+}
+
+G10_MPI_INLINE_DECL mpi_limb_t
+mpihelp_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)
+{
+ mpi_limb_t cy = 0;
+
+ if (s2_size)
+ cy = mpihelp_sub_n(res_ptr, s1_ptr, s2_ptr, s2_size);
+
+ if (s1_size - s2_size)
+ cy = mpihelp_sub_1(res_ptr + s2_size, s1_ptr + s2_size,
+ s1_size - s2_size, cy);
+ return cy;
+}
+
+#endif /*G10_MPI_INLINE_H */
diff --git a/lib/mpi/mpi-internal.h b/lib/mpi/mpi-internal.h
new file mode 100644
index 000000000..554002182
--- /dev/null
+++ b/lib/mpi/mpi-internal.h
@@ -0,0 +1,232 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/* mpi-internal.h - Internal to the Multi Precision Integers
+ * Copyright (C) 1994, 1996 Free Software Foundation, Inc.
+ * Copyright (C) 1998, 2000 Free Software Foundation, Inc.
+ *
+ * This file is part of GnuPG.
+ *
+ * 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.
+ */
+
+#ifndef G10_MPI_INTERNAL_H
+#define G10_MPI_INTERNAL_H
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/mpi.h>
+#include <linux/errno.h>
+
+#define log_debug printk
+#define log_bug printk
+
+#define assert(x) \
+ do { \
+ if (!x) \
+ log_bug("failed assertion\n"); \
+ } while (0);
+
+/* 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 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_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 __maybe_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 --*/
+mpi_ptr_t mpi_alloc_limb_space(unsigned nlimbs);
+void mpi_free_limb_space(mpi_ptr_t a);
+void mpi_assign_limb_space(MPI a, mpi_ptr_t ap, unsigned nlimbs);
+
+static inline mpi_limb_t mpihelp_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 mpihelp_add_n(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr,
+ mpi_ptr_t s2_ptr, mpi_size_t size);
+static inline mpi_limb_t mpihelp_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);
+
+static inline mpi_limb_t mpihelp_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 mpihelp_sub_n(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr,
+ mpi_ptr_t s2_ptr, mpi_size_t size);
+static inline mpi_limb_t mpihelp_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 mpihelp_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;
+ mpi_size_t tspace_size;
+ mpi_ptr_t tp;
+ mpi_size_t tp_size;
+};
+
+void mpihelp_release_karatsuba_ctx(struct karatsuba_ctx *ctx);
+
+mpi_limb_t mpihelp_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 mpihelp_submul_1(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr,
+ mpi_size_t s1_size, mpi_limb_t s2_limb);
+int mpihelp_mul(mpi_ptr_t prodp, mpi_ptr_t up, mpi_size_t usize,
+ mpi_ptr_t vp, mpi_size_t vsize, mpi_limb_t *_result);
+void mpih_sqr_n_basecase(mpi_ptr_t prodp, mpi_ptr_t up, mpi_size_t size);
+void mpih_sqr_n(mpi_ptr_t prodp, mpi_ptr_t up, mpi_size_t size,
+ mpi_ptr_t tspace);
+void mpihelp_mul_n(mpi_ptr_t prodp,
+ mpi_ptr_t up, mpi_ptr_t vp, mpi_size_t size);
+
+int mpihelp_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);
+
+/*-- generic_mpih-mul1.c --*/
+mpi_limb_t mpihelp_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 mpihelp_mod_1(mpi_ptr_t dividend_ptr, mpi_size_t dividend_size,
+ mpi_limb_t divisor_limb);
+mpi_limb_t mpihelp_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 mpihelp_divmod_1(mpi_ptr_t quot_ptr,
+ mpi_ptr_t dividend_ptr, mpi_size_t dividend_size,
+ mpi_limb_t divisor_limb);
+
+/*-- generic_mpih-[lr]shift.c --*/
+mpi_limb_t mpihelp_lshift(mpi_ptr_t wp, mpi_ptr_t up, mpi_size_t usize,
+ unsigned cnt);
+mpi_limb_t mpihelp_rshift(mpi_ptr_t wp, mpi_ptr_t up, mpi_size_t usize,
+ unsigned cnt);
+
+/* 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/lib/mpi/mpi-inv.c b/lib/mpi/mpi-inv.c
new file mode 100644
index 000000000..61e37d18f
--- /dev/null
+++ b/lib/mpi/mpi-inv.c
@@ -0,0 +1,143 @@
+/* mpi-inv.c - MPI functions
+ * Copyright (C) 1998, 2001, 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, see <http://www.gnu.org/licenses/>.
+ */
+
+#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, MPI a, MPI n)
+{
+ /* Extended Euclid's algorithm (See TAOCP Vol II, 4.5.2, Alg X)
+ * modified according to Michael Penk's solution for Exercise 35
+ * with further enhancement
+ */
+ MPI u, v, u1, u2 = NULL, u3, v1, v2 = NULL, v3, t1, t2 = NULL, t3;
+ unsigned int k;
+ int sign;
+ int odd;
+
+ if (!mpi_cmp_ui(a, 0))
+ return 0; /* Inverse does not exists. */
+ if (!mpi_cmp_ui(n, 1))
+ return 0; /* Inverse does not exists. */
+
+ u = mpi_copy(a);
+ v = mpi_copy(n);
+
+ for (k = 0; !mpi_test_bit(u, 0) && !mpi_test_bit(v, 0); k++) {
+ mpi_rshift(u, u, 1);
+ mpi_rshift(v, v, 1);
+ }
+ odd = mpi_test_bit(v, 0);
+
+ u1 = mpi_alloc_set_ui(1);
+ if (!odd)
+ u2 = mpi_alloc_set_ui(0);
+ u3 = mpi_copy(u);
+ v1 = mpi_copy(v);
+ if (!odd) {
+ v2 = mpi_alloc(mpi_get_nlimbs(u));
+ mpi_sub(v2, u1, u); /* U is used as const 1 */
+ }
+ v3 = mpi_copy(v);
+ if (mpi_test_bit(u, 0)) { /* u is odd */
+ t1 = mpi_alloc_set_ui(0);
+ if (!odd) {
+ t2 = mpi_alloc_set_ui(1);
+ t2->sign = 1;
+ }
+ t3 = mpi_copy(v);
+ t3->sign = !t3->sign;
+ goto Y4;
+ } else {
+ t1 = mpi_alloc_set_ui(1);
+ if (!odd)
+ t2 = mpi_alloc_set_ui(0);
+ t3 = mpi_copy(u);
+ }
+
+ do {
+ do {
+ if (!odd) {
+ if (mpi_test_bit(t1, 0) || mpi_test_bit(t2, 0)) {
+ /* one is odd */
+ mpi_add(t1, t1, v);
+ mpi_sub(t2, t2, u);
+ }
+ mpi_rshift(t1, t1, 1);
+ mpi_rshift(t2, t2, 1);
+ mpi_rshift(t3, t3, 1);
+ } else {
+ if (mpi_test_bit(t1, 0))
+ mpi_add(t1, t1, v);
+ mpi_rshift(t1, t1, 1);
+ mpi_rshift(t3, t3, 1);
+ }
+Y4:
+ ;
+ } while (!mpi_test_bit(t3, 0)); /* while t3 is even */
+
+ if (!t3->sign) {
+ mpi_set(u1, t1);
+ if (!odd)
+ mpi_set(u2, t2);
+ mpi_set(u3, t3);
+ } else {
+ mpi_sub(v1, v, t1);
+ sign = u->sign; u->sign = !u->sign;
+ if (!odd)
+ mpi_sub(v2, u, t2);
+ u->sign = sign;
+ sign = t3->sign; t3->sign = !t3->sign;
+ mpi_set(v3, t3);
+ t3->sign = sign;
+ }
+ mpi_sub(t1, u1, v1);
+ if (!odd)
+ mpi_sub(t2, u2, v2);
+ mpi_sub(t3, u3, v3);
+ if (t1->sign) {
+ mpi_add(t1, t1, v);
+ if (!odd)
+ mpi_sub(t2, t2, u);
+ }
+ } while (mpi_cmp_ui(t3, 0)); /* while t3 != 0 */
+ /* mpi_lshift( u3, k ); */
+ mpi_set(x, u1);
+
+ 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 1;
+}
+EXPORT_SYMBOL_GPL(mpi_invm);
diff --git a/lib/mpi/mpi-mod.c b/lib/mpi/mpi-mod.c
new file mode 100644
index 000000000..54fcc0156
--- /dev/null
+++ b/lib/mpi/mpi-mod.c
@@ -0,0 +1,157 @@
+/* mpi-mod.c - Modular reduction
+ * Copyright (C) 1998, 1999, 2001, 2002, 2003,
+ * 2007 Free Software Foundation, Inc.
+ *
+ * This file is part of Libgcrypt.
+ */
+
+
+#include "mpi-internal.h"
+#include "longlong.h"
+
+/* Context used with Barrett reduction. */
+struct barrett_ctx_s {
+ MPI m; /* The modulus - may not be modified. */
+ int m_copied; /* If true, M needs to be released. */
+ int k;
+ MPI y;
+ MPI r1; /* Helper MPI. */
+ MPI r2; /* Helper MPI. */
+ MPI r3; /* Helper MPI allocated on demand. */
+};
+
+
+
+void mpi_mod(MPI rem, MPI dividend, MPI divisor)
+{
+ mpi_fdiv_r(rem, dividend, divisor);
+}
+
+/* This function returns a new context for Barrett based operations on
+ * the modulus M. This context needs to be released using
+ * _gcry_mpi_barrett_free. If COPY is true M will be transferred to
+ * the context and the user may change M. If COPY is false, M may not
+ * be changed until gcry_mpi_barrett_free has been called.
+ */
+mpi_barrett_t mpi_barrett_init(MPI m, int copy)
+{
+ mpi_barrett_t ctx;
+ MPI tmp;
+
+ mpi_normalize(m);
+ ctx = kcalloc(1, sizeof(*ctx), GFP_KERNEL);
+ if (!ctx)
+ return NULL;
+
+ if (copy) {
+ ctx->m = mpi_copy(m);
+ ctx->m_copied = 1;
+ } else
+ ctx->m = m;
+
+ ctx->k = mpi_get_nlimbs(m);
+ tmp = mpi_alloc(ctx->k + 1);
+
+ /* Barrett precalculation: y = floor(b^(2k) / m). */
+ mpi_set_ui(tmp, 1);
+ mpi_lshift_limbs(tmp, 2 * ctx->k);
+ mpi_fdiv_q(tmp, tmp, m);
+
+ ctx->y = tmp;
+ ctx->r1 = mpi_alloc(2 * ctx->k + 1);
+ ctx->r2 = mpi_alloc(2 * ctx->k + 1);
+
+ return ctx;
+}
+
+void mpi_barrett_free(mpi_barrett_t ctx)
+{
+ if (ctx) {
+ mpi_free(ctx->y);
+ mpi_free(ctx->r1);
+ mpi_free(ctx->r2);
+ if (ctx->r3)
+ mpi_free(ctx->r3);
+ if (ctx->m_copied)
+ mpi_free(ctx->m);
+ kfree(ctx);
+ }
+}
+
+
+/* R = X mod M
+ *
+ * Using Barrett reduction. Before using this function
+ * _gcry_mpi_barrett_init must have been called to do the
+ * precalculations. CTX is the context created by this precalculation
+ * and also conveys M. If the Barret reduction could no be done a
+ * straightforward reduction method is used.
+ *
+ * We assume that these conditions are met:
+ * Input: x =(x_2k-1 ...x_0)_b
+ * m =(m_k-1 ....m_0)_b with m_k-1 != 0
+ * Output: r = x mod m
+ */
+void mpi_mod_barrett(MPI r, MPI x, mpi_barrett_t ctx)
+{
+ MPI m = ctx->m;
+ int k = ctx->k;
+ MPI y = ctx->y;
+ MPI r1 = ctx->r1;
+ MPI r2 = ctx->r2;
+ int sign;
+
+ mpi_normalize(x);
+ if (mpi_get_nlimbs(x) > 2*k) {
+ mpi_mod(r, x, m);
+ return;
+ }
+
+ sign = x->sign;
+ x->sign = 0;
+
+ /* 1. q1 = floor( x / b^k-1)
+ * q2 = q1 * y
+ * q3 = floor( q2 / b^k+1 )
+ * Actually, we don't need qx, we can work direct on r2
+ */
+ mpi_set(r2, x);
+ mpi_rshift_limbs(r2, k-1);
+ mpi_mul(r2, r2, y);
+ mpi_rshift_limbs(r2, k+1);
+
+ /* 2. r1 = x mod b^k+1
+ * r2 = q3 * m mod b^k+1
+ * r = r1 - r2
+ * 3. if r < 0 then r = r + b^k+1
+ */
+ mpi_set(r1, x);
+ if (r1->nlimbs > k+1) /* Quick modulo operation. */
+ r1->nlimbs = k+1;
+ mpi_mul(r2, r2, m);
+ if (r2->nlimbs > k+1) /* Quick modulo operation. */
+ r2->nlimbs = k+1;
+ mpi_sub(r, r1, r2);
+
+ if (mpi_has_sign(r)) {
+ if (!ctx->r3) {
+ ctx->r3 = mpi_alloc(k + 2);
+ mpi_set_ui(ctx->r3, 1);
+ mpi_lshift_limbs(ctx->r3, k + 1);
+ }
+ mpi_add(r, r, ctx->r3);
+ }
+
+ /* 4. while r >= m do r = r - m */
+ while (mpi_cmp(r, m) >= 0)
+ mpi_sub(r, r, m);
+
+ x->sign = sign;
+}
+
+
+void mpi_mul_barrett(MPI w, MPI u, MPI v, mpi_barrett_t ctx)
+{
+ mpi_mul(w, u, v);
+ mpi_mod_barrett(w, w, ctx);
+}
diff --git a/lib/mpi/mpi-mul.c b/lib/mpi/mpi-mul.c
new file mode 100644
index 000000000..7f4eda856
--- /dev/null
+++ b/lib/mpi/mpi-mul.c
@@ -0,0 +1,92 @@
+/* mpi-mul.c - MPI functions
+ * Copyright (C) 1994, 1996, 1998, 2001, 2002,
+ * 2003 Free Software Foundation, Inc.
+ *
+ * This file is part of Libgcrypt.
+ *
+ * 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.
+ */
+
+#include "mpi-internal.h"
+
+void mpi_mul(MPI w, MPI u, MPI v)
+{
+ 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 < wsize) {
+ if (wp == up || wp == vp) {
+ wp = mpi_alloc_limb_space(wsize);
+ assign_wp = 1;
+ } else {
+ mpi_resize(w, wsize);
+ 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);
+ /* 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);
+ /* Copy to the temporary space. */
+ MPN_COPY(vp, wp, vsize);
+ }
+ }
+
+ if (!vsize)
+ wsize = 0;
+ else {
+ mpihelp_mul(wp, up, usize, vp, vsize, &cy);
+ wsize -= cy ? 0:1;
+ }
+
+ if (assign_wp)
+ mpi_assign_limb_space(w, wp, wsize);
+ w->nlimbs = wsize;
+ w->sign = sign_product;
+ if (tmp_limb)
+ mpi_free_limb_space(tmp_limb);
+}
+EXPORT_SYMBOL_GPL(mpi_mul);
+
+void mpi_mulm(MPI w, MPI u, MPI v, MPI m)
+{
+ mpi_mul(w, u, v);
+ mpi_tdiv_r(w, w, m);
+}
+EXPORT_SYMBOL_GPL(mpi_mulm);
diff --git a/lib/mpi/mpi-pow.c b/lib/mpi/mpi-pow.c
new file mode 100644
index 000000000..2fd7a46d5
--- /dev/null
+++ b/lib/mpi/mpi-pow.c
@@ -0,0 +1,314 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* mpi-pow.c - MPI functions
+ * Copyright (C) 1994, 1996, 1998, 2000 Free Software Foundation, Inc.
+ *
+ * This file is part of GnuPG.
+ *
+ * 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/sched.h>
+#include <linux/string.h>
+#include "mpi-internal.h"
+#include "longlong.h"
+
+/****************
+ * RES = BASE ^ EXP mod MOD
+ */
+int mpi_powm(MPI res, MPI base, MPI exp, MPI mod)
+{
+ mpi_ptr_t mp_marker = NULL, bp_marker = NULL, ep_marker = NULL;
+ struct karatsuba_ctx karactx = {};
+ mpi_ptr_t xp_marker = NULL;
+ mpi_ptr_t tspace = NULL;
+ mpi_ptr_t rp, ep, mp, bp;
+ mpi_size_t esize, msize, bsize, rsize;
+ int msign, bsign, rsign;
+ mpi_size_t size;
+ int mod_shift_cnt;
+ int negative_result;
+ int assign_rp = 0;
+ mpi_size_t tsize = 0; /* to avoid compiler warning */
+ /* fixme: we should check that the warning is void */
+ int rc = -ENOMEM;
+
+ esize = exp->nlimbs;
+ msize = mod->nlimbs;
+ size = 2 * msize;
+ msign = mod->sign;
+
+ rp = res->d;
+ ep = exp->d;
+
+ if (!msize)
+ return -EINVAL;
+
+ if (!esize) {
+ /* Exponent is zero, result is 1 mod MOD, i.e., 1 or 0
+ * depending on if MOD equals 1. */
+ res->nlimbs = (msize == 1 && mod->d[0] == 1) ? 0 : 1;
+ if (res->nlimbs) {
+ if (mpi_resize(res, 1) < 0)
+ goto enomem;
+ rp = res->d;
+ rp[0] = 1;
+ }
+ res->sign = 0;
+ goto leave;
+ }
+
+ /* Normalize MOD (i.e. make its most significant bit set) as required by
+ * mpn_divrem. This will make the intermediate values in the calculation
+ * slightly larger, but the correct result is obtained after a final
+ * reduction using the original MOD value. */
+ mp = mp_marker = mpi_alloc_limb_space(msize);
+ if (!mp)
+ goto enomem;
+ mod_shift_cnt = count_leading_zeros(mod->d[msize - 1]);
+ if (mod_shift_cnt)
+ mpihelp_lshift(mp, mod->d, msize, mod_shift_cnt);
+ else
+ MPN_COPY(mp, mod->d, msize);
+
+ bsize = base->nlimbs;
+ bsign = base->sign;
+ if (bsize > msize) { /* The base is larger than the module. Reduce it. */
+ /* Allocate (BSIZE + 1) with space for remainder and quotient.
+ * (The quotient is (bsize - msize + 1) limbs.) */
+ bp = bp_marker = mpi_alloc_limb_space(bsize + 1);
+ if (!bp)
+ goto enomem;
+ MPN_COPY(bp, base->d, bsize);
+ /* We don't care about the quotient, store it above the remainder,
+ * at BP + MSIZE. */
+ mpihelp_divrem(bp + msize, 0, bp, bsize, mp, msize);
+ bsize = msize;
+ /* Canonicalize the base, since we are going to multiply with it
+ * quite a few times. */
+ MPN_NORMALIZE(bp, bsize);
+ } else
+ bp = base->d;
+
+ if (!bsize) {
+ res->nlimbs = 0;
+ res->sign = 0;
+ goto leave;
+ }
+
+ if (res->alloced < size) {
+ /* We have to allocate more space for RES. If any of the input
+ * parameters are identical to RES, defer deallocation of the old
+ * space. */
+ if (rp == ep || rp == mp || rp == bp) {
+ rp = mpi_alloc_limb_space(size);
+ if (!rp)
+ goto enomem;
+ assign_rp = 1;
+ } else {
+ if (mpi_resize(res, size) < 0)
+ goto enomem;
+ rp = res->d;
+ }
+ } else { /* Make BASE, EXP and MOD not overlap with RES. */
+ if (rp == bp) {
+ /* RES and BASE are identical. Allocate temp. space for BASE. */
+ BUG_ON(bp_marker);
+ bp = bp_marker = mpi_alloc_limb_space(bsize);
+ if (!bp)
+ goto enomem;
+ MPN_COPY(bp, rp, bsize);
+ }
+ if (rp == ep) {
+ /* RES and EXP are identical. Allocate temp. space for EXP. */
+ ep = ep_marker = mpi_alloc_limb_space(esize);
+ if (!ep)
+ goto enomem;
+ MPN_COPY(ep, rp, esize);
+ }
+ if (rp == mp) {
+ /* RES and MOD are identical. Allocate temporary space for MOD. */
+ BUG_ON(mp_marker);
+ mp = mp_marker = mpi_alloc_limb_space(msize);
+ if (!mp)
+ goto enomem;
+ MPN_COPY(mp, rp, msize);
+ }
+ }
+
+ MPN_COPY(rp, bp, bsize);
+ rsize = bsize;
+ rsign = bsign;
+
+ {
+ mpi_size_t i;
+ mpi_ptr_t xp;
+ int c;
+ mpi_limb_t e;
+ mpi_limb_t carry_limb;
+
+ xp = xp_marker = mpi_alloc_limb_space(2 * (msize + 1));
+ if (!xp)
+ goto enomem;
+
+ negative_result = (ep[0] & 1) && base->sign;
+
+ i = esize - 1;
+ e = ep[i];
+ c = count_leading_zeros(e);
+ e = (e << c) << 1; /* shift the exp bits to the left, lose msb */
+ c = BITS_PER_MPI_LIMB - 1 - c;
+
+ /* Main loop.
+ *
+ * Make the result be pointed to alternately by XP and RP. This
+ * helps us avoid block copying, which would otherwise be necessary
+ * with the overlap restrictions of mpihelp_divmod. With 50% probability
+ * the result after this loop will be in the area originally pointed
+ * by RP (==RES->d), and with 50% probability in the area originally
+ * pointed to by XP.
+ */
+
+ for (;;) {
+ while (c) {
+ mpi_ptr_t tp;
+ mpi_size_t xsize;
+
+ /*if (mpihelp_mul_n(xp, rp, rp, rsize) < 0) goto enomem */
+ if (rsize < KARATSUBA_THRESHOLD)
+ mpih_sqr_n_basecase(xp, rp, rsize);
+ else {
+ if (!tspace) {
+ tsize = 2 * rsize;
+ tspace =
+ mpi_alloc_limb_space(tsize);
+ if (!tspace)
+ goto enomem;
+ } else if (tsize < (2 * rsize)) {
+ mpi_free_limb_space(tspace);
+ tsize = 2 * rsize;
+ tspace =
+ mpi_alloc_limb_space(tsize);
+ if (!tspace)
+ goto enomem;
+ }
+ mpih_sqr_n(xp, rp, rsize, tspace);
+ }
+
+ xsize = 2 * rsize;
+ if (xsize > msize) {
+ mpihelp_divrem(xp + msize, 0, xp, xsize,
+ mp, msize);
+ xsize = msize;
+ }
+
+ tp = rp;
+ rp = xp;
+ xp = tp;
+ rsize = xsize;
+
+ if ((mpi_limb_signed_t) e < 0) {
+ /*mpihelp_mul( xp, rp, rsize, bp, bsize ); */
+ if (bsize < KARATSUBA_THRESHOLD) {
+ mpi_limb_t tmp;
+ if (mpihelp_mul
+ (xp, rp, rsize, bp, bsize,
+ &tmp) < 0)
+ goto enomem;
+ } else {
+ if (mpihelp_mul_karatsuba_case
+ (xp, rp, rsize, bp, bsize,
+ &karactx) < 0)
+ goto enomem;
+ }
+
+ xsize = rsize + bsize;
+ if (xsize > msize) {
+ mpihelp_divrem(xp + msize, 0,
+ xp, xsize, mp,
+ msize);
+ xsize = msize;
+ }
+
+ tp = rp;
+ rp = xp;
+ xp = tp;
+ rsize = xsize;
+ }
+ e <<= 1;
+ c--;
+ cond_resched();
+ }
+
+ i--;
+ if (i < 0)
+ break;
+ e = ep[i];
+ c = BITS_PER_MPI_LIMB;
+ }
+
+ /* We shifted MOD, the modulo reduction argument, left MOD_SHIFT_CNT
+ * steps. Adjust the result by reducing it with the original MOD.
+ *
+ * Also make sure the result is put in RES->d (where it already
+ * might be, see above).
+ */
+ if (mod_shift_cnt) {
+ carry_limb =
+ mpihelp_lshift(res->d, rp, rsize, mod_shift_cnt);
+ rp = res->d;
+ if (carry_limb) {
+ rp[rsize] = carry_limb;
+ rsize++;
+ }
+ } else {
+ MPN_COPY(res->d, rp, rsize);
+ rp = res->d;
+ }
+
+ if (rsize >= msize) {
+ mpihelp_divrem(rp + msize, 0, rp, rsize, mp, msize);
+ rsize = msize;
+ }
+
+ /* Remove any leading zero words from the result. */
+ if (mod_shift_cnt)
+ mpihelp_rshift(rp, rp, rsize, mod_shift_cnt);
+ MPN_NORMALIZE(rp, rsize);
+ }
+
+ if (negative_result && rsize) {
+ if (mod_shift_cnt)
+ mpihelp_rshift(mp, mp, msize, mod_shift_cnt);
+ mpihelp_sub(rp, mp, msize, rp, rsize);
+ rsize = msize;
+ rsign = msign;
+ MPN_NORMALIZE(rp, rsize);
+ }
+ res->nlimbs = rsize;
+ res->sign = rsign;
+
+leave:
+ rc = 0;
+enomem:
+ mpihelp_release_karatsuba_ctx(&karactx);
+ if (assign_rp)
+ mpi_assign_limb_space(res, rp, size);
+ if (mp_marker)
+ mpi_free_limb_space(mp_marker);
+ if (bp_marker)
+ mpi_free_limb_space(bp_marker);
+ if (ep_marker)
+ mpi_free_limb_space(ep_marker);
+ if (xp_marker)
+ mpi_free_limb_space(xp_marker);
+ if (tspace)
+ mpi_free_limb_space(tspace);
+ return rc;
+}
+EXPORT_SYMBOL_GPL(mpi_powm);
diff --git a/lib/mpi/mpi-sub-ui.c b/lib/mpi/mpi-sub-ui.c
new file mode 100644
index 000000000..b41b082b5
--- /dev/null
+++ b/lib/mpi/mpi-sub-ui.c
@@ -0,0 +1,78 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* mpi-sub-ui.c - Subtract an unsigned integer from an MPI.
+ *
+ * Copyright 1991, 1993, 1994, 1996, 1999-2002, 2004, 2012, 2013, 2015
+ * Free Software Foundation, Inc.
+ *
+ * This file was based on the GNU MP Library source file:
+ * https://gmplib.org/repo/gmp-6.2/file/510b83519d1c/mpz/aors_ui.h
+ *
+ * The GNU MP Library is free software; you can redistribute it and/or modify
+ * it under the terms of either:
+ *
+ * * the GNU Lesser General Public License as published by the Free
+ * Software Foundation; either version 3 of the License, or (at your
+ * option) any later version.
+ *
+ * or
+ *
+ * * 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.
+ *
+ * or both in parallel, as here.
+ *
+ * The GNU MP Library 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 copies of the GNU General Public License and the
+ * GNU Lesser General Public License along with the GNU MP Library. If not,
+ * see https://www.gnu.org/licenses/.
+ */
+
+#include "mpi-internal.h"
+
+int mpi_sub_ui(MPI w, MPI u, unsigned long vval)
+{
+ if (u->nlimbs == 0) {
+ if (mpi_resize(w, 1) < 0)
+ return -ENOMEM;
+ w->d[0] = vval;
+ w->nlimbs = (vval != 0);
+ w->sign = (vval != 0);
+ return 0;
+ }
+
+ /* If not space for W (and possible carry), increase space. */
+ if (mpi_resize(w, u->nlimbs + 1))
+ return -ENOMEM;
+
+ if (u->sign) {
+ mpi_limb_t cy;
+
+ cy = mpihelp_add_1(w->d, u->d, u->nlimbs, (mpi_limb_t) vval);
+ w->d[u->nlimbs] = cy;
+ w->nlimbs = u->nlimbs + cy;
+ w->sign = 1;
+ } else {
+ /* The signs are different. Need exact comparison to determine
+ * which operand to subtract from which.
+ */
+ if (u->nlimbs == 1 && u->d[0] < vval) {
+ w->d[0] = vval - u->d[0];
+ w->nlimbs = 1;
+ w->sign = 1;
+ } else {
+ mpihelp_sub_1(w->d, u->d, u->nlimbs, (mpi_limb_t) vval);
+ /* Size can decrease with at most one limb. */
+ w->nlimbs = (u->nlimbs - (w->d[u->nlimbs - 1] == 0));
+ w->sign = 0;
+ }
+ }
+
+ mpi_normalize(w);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(mpi_sub_ui);
diff --git a/lib/mpi/mpicoder.c b/lib/mpi/mpicoder.c
new file mode 100644
index 000000000..3cb6bd148
--- /dev/null
+++ b/lib/mpi/mpicoder.c
@@ -0,0 +1,752 @@
+/* mpicoder.c - Coder for the external representation of MPIs
+ * 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 <linux/bitops.h>
+#include <linux/count_zeros.h>
+#include <linux/byteorder/generic.h>
+#include <linux/scatterlist.h>
+#include <linux/string.h>
+#include "mpi-internal.h"
+
+#define MAX_EXTERN_SCAN_BYTES (16*1024*1024)
+#define MAX_EXTERN_MPI_BITS 16384
+
+/**
+ * mpi_read_raw_data - Read a raw byte stream as a positive integer
+ * @xbuffer: The data to read
+ * @nbytes: The amount of data to read
+ */
+MPI mpi_read_raw_data(const void *xbuffer, size_t nbytes)
+{
+ const uint8_t *buffer = xbuffer;
+ int i, j;
+ unsigned nbits, nlimbs;
+ mpi_limb_t a;
+ MPI val = NULL;
+
+ while (nbytes > 0 && buffer[0] == 0) {
+ buffer++;
+ nbytes--;
+ }
+
+ nbits = nbytes * 8;
+ if (nbits > MAX_EXTERN_MPI_BITS) {
+ pr_info("MPI: mpi too large (%u bits)\n", nbits);
+ return NULL;
+ }
+ if (nbytes > 0)
+ nbits -= count_leading_zeros(buffer[0]) - (BITS_PER_LONG - 8);
+
+ nlimbs = DIV_ROUND_UP(nbytes, BYTES_PER_MPI_LIMB);
+ val = mpi_alloc(nlimbs);
+ if (!val)
+ return NULL;
+ val->nbits = nbits;
+ val->sign = 0;
+ val->nlimbs = nlimbs;
+
+ if (nbytes > 0) {
+ i = BYTES_PER_MPI_LIMB - nbytes % BYTES_PER_MPI_LIMB;
+ i %= BYTES_PER_MPI_LIMB;
+ for (j = nlimbs; j > 0; j--) {
+ a = 0;
+ for (; i < BYTES_PER_MPI_LIMB; i++) {
+ a <<= 8;
+ a |= *buffer++;
+ }
+ i = 0;
+ val->d[j - 1] = a;
+ }
+ }
+ return val;
+}
+EXPORT_SYMBOL_GPL(mpi_read_raw_data);
+
+MPI mpi_read_from_buffer(const void *xbuffer, unsigned *ret_nread)
+{
+ const uint8_t *buffer = xbuffer;
+ unsigned int nbits, nbytes;
+ MPI val;
+
+ if (*ret_nread < 2)
+ return ERR_PTR(-EINVAL);
+ nbits = buffer[0] << 8 | buffer[1];
+
+ if (nbits > MAX_EXTERN_MPI_BITS) {
+ pr_info("MPI: mpi too large (%u bits)\n", nbits);
+ return ERR_PTR(-EINVAL);
+ }
+
+ nbytes = DIV_ROUND_UP(nbits, 8);
+ if (nbytes + 2 > *ret_nread) {
+ pr_info("MPI: mpi larger than buffer nbytes=%u ret_nread=%u\n",
+ nbytes, *ret_nread);
+ return ERR_PTR(-EINVAL);
+ }
+
+ val = mpi_read_raw_data(buffer + 2, nbytes);
+ if (!val)
+ return ERR_PTR(-ENOMEM);
+
+ *ret_nread = nbytes + 2;
+ return val;
+}
+EXPORT_SYMBOL_GPL(mpi_read_from_buffer);
+
+/****************
+ * Fill the mpi VAL from the hex string in STR.
+ */
+int mpi_fromstr(MPI val, const char *str)
+{
+ int sign = 0;
+ int prepend_zero = 0;
+ int i, j, c, c1, c2;
+ unsigned int nbits, nbytes, nlimbs;
+ mpi_limb_t a;
+
+ if (*str == '-') {
+ sign = 1;
+ str++;
+ }
+
+ /* Skip optional hex prefix. */
+ if (*str == '0' && str[1] == 'x')
+ str += 2;
+
+ nbits = strlen(str);
+ if (nbits > MAX_EXTERN_SCAN_BYTES) {
+ mpi_clear(val);
+ return -EINVAL;
+ }
+ nbits *= 4;
+ if ((nbits % 8))
+ prepend_zero = 1;
+
+ nbytes = (nbits+7) / 8;
+ nlimbs = (nbytes+BYTES_PER_MPI_LIMB-1) / BYTES_PER_MPI_LIMB;
+
+ if (val->alloced < nlimbs)
+ mpi_resize(val, nlimbs);
+
+ i = BYTES_PER_MPI_LIMB - (nbytes % BYTES_PER_MPI_LIMB);
+ i %= BYTES_PER_MPI_LIMB;
+ j = val->nlimbs = nlimbs;
+ val->sign = sign;
+ for (; j > 0; j--) {
+ a = 0;
+ for (; i < BYTES_PER_MPI_LIMB; i++) {
+ if (prepend_zero) {
+ c1 = '0';
+ prepend_zero = 0;
+ } else
+ c1 = *str++;
+
+ if (!c1) {
+ mpi_clear(val);
+ return -EINVAL;
+ }
+ c2 = *str++;
+ if (!c2) {
+ mpi_clear(val);
+ return -EINVAL;
+ }
+ if (c1 >= '0' && c1 <= '9')
+ c = c1 - '0';
+ else if (c1 >= 'a' && c1 <= 'f')
+ c = c1 - 'a' + 10;
+ else if (c1 >= 'A' && c1 <= 'F')
+ c = c1 - 'A' + 10;
+ else {
+ mpi_clear(val);
+ return -EINVAL;
+ }
+ c <<= 4;
+ if (c2 >= '0' && c2 <= '9')
+ c |= c2 - '0';
+ else if (c2 >= 'a' && c2 <= 'f')
+ c |= c2 - 'a' + 10;
+ else if (c2 >= 'A' && c2 <= 'F')
+ c |= c2 - 'A' + 10;
+ else {
+ mpi_clear(val);
+ return -EINVAL;
+ }
+ a <<= 8;
+ a |= c;
+ }
+ i = 0;
+ val->d[j-1] = a;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(mpi_fromstr);
+
+MPI mpi_scanval(const char *string)
+{
+ MPI a;
+
+ a = mpi_alloc(0);
+ if (!a)
+ return NULL;
+
+ if (mpi_fromstr(a, string)) {
+ mpi_free(a);
+ return NULL;
+ }
+ mpi_normalize(a);
+ return a;
+}
+EXPORT_SYMBOL_GPL(mpi_scanval);
+
+static int count_lzeros(MPI a)
+{
+ mpi_limb_t alimb;
+ int i, lzeros = 0;
+
+ for (i = a->nlimbs - 1; i >= 0; i--) {
+ alimb = a->d[i];
+ if (alimb == 0) {
+ lzeros += sizeof(mpi_limb_t);
+ } else {
+ lzeros += count_leading_zeros(alimb) / 8;
+ break;
+ }
+ }
+ return lzeros;
+}
+
+/**
+ * mpi_read_buffer() - read MPI to a buffer provided by user (msb first)
+ *
+ * @a: a multi precision integer
+ * @buf: buffer to which the output will be written to. Needs to be at
+ * least mpi_get_size(a) long.
+ * @buf_len: size of the buf.
+ * @nbytes: receives the actual length of the data written on success and
+ * the data to-be-written on -EOVERFLOW in case buf_len was too
+ * small.
+ * @sign: if not NULL, it will be set to the sign of a.
+ *
+ * Return: 0 on success or error code in case of error
+ */
+int mpi_read_buffer(MPI a, uint8_t *buf, unsigned buf_len, unsigned *nbytes,
+ int *sign)
+{
+ uint8_t *p;
+#if BYTES_PER_MPI_LIMB == 4
+ __be32 alimb;
+#elif BYTES_PER_MPI_LIMB == 8
+ __be64 alimb;
+#else
+#error please implement for this limb size.
+#endif
+ unsigned int n = mpi_get_size(a);
+ int i, lzeros;
+
+ if (!buf || !nbytes)
+ return -EINVAL;
+
+ if (sign)
+ *sign = a->sign;
+
+ lzeros = count_lzeros(a);
+
+ if (buf_len < n - lzeros) {
+ *nbytes = n - lzeros;
+ return -EOVERFLOW;
+ }
+
+ p = buf;
+ *nbytes = n - lzeros;
+
+ for (i = a->nlimbs - 1 - lzeros / BYTES_PER_MPI_LIMB,
+ lzeros %= BYTES_PER_MPI_LIMB;
+ i >= 0; i--) {
+#if BYTES_PER_MPI_LIMB == 4
+ alimb = cpu_to_be32(a->d[i]);
+#elif BYTES_PER_MPI_LIMB == 8
+ alimb = cpu_to_be64(a->d[i]);
+#else
+#error please implement for this limb size.
+#endif
+ memcpy(p, (u8 *)&alimb + lzeros, BYTES_PER_MPI_LIMB - lzeros);
+ p += BYTES_PER_MPI_LIMB - lzeros;
+ lzeros = 0;
+ }
+ return 0;
+}
+EXPORT_SYMBOL_GPL(mpi_read_buffer);
+
+/*
+ * mpi_get_buffer() - Returns an allocated buffer with the MPI (msb first).
+ * Caller must free the return string.
+ * This function does return a 0 byte buffer with nbytes set to zero if the
+ * value of A is zero.
+ *
+ * @a: a multi precision integer.
+ * @nbytes: receives the length of this buffer.
+ * @sign: if not NULL, it will be set to the sign of the a.
+ *
+ * Return: Pointer to MPI buffer or NULL on error
+ */
+void *mpi_get_buffer(MPI a, unsigned *nbytes, int *sign)
+{
+ uint8_t *buf;
+ unsigned int n;
+ int ret;
+
+ if (!nbytes)
+ return NULL;
+
+ n = mpi_get_size(a);
+
+ if (!n)
+ n++;
+
+ buf = kmalloc(n, GFP_KERNEL);
+
+ if (!buf)
+ return NULL;
+
+ ret = mpi_read_buffer(a, buf, n, nbytes, sign);
+
+ if (ret) {
+ kfree(buf);
+ return NULL;
+ }
+ return buf;
+}
+EXPORT_SYMBOL_GPL(mpi_get_buffer);
+
+/**
+ * mpi_write_to_sgl() - Funnction exports MPI to an sgl (msb first)
+ *
+ * This function works in the same way as the mpi_read_buffer, but it
+ * takes an sgl instead of u8 * buf.
+ *
+ * @a: a multi precision integer
+ * @sgl: scatterlist to write to. Needs to be at least
+ * mpi_get_size(a) long.
+ * @nbytes: the number of bytes to write. Leading bytes will be
+ * filled with zero.
+ * @sign: if not NULL, it will be set to the sign of a.
+ *
+ * Return: 0 on success or error code in case of error
+ */
+int mpi_write_to_sgl(MPI a, struct scatterlist *sgl, unsigned nbytes,
+ int *sign)
+{
+ u8 *p, *p2;
+#if BYTES_PER_MPI_LIMB == 4
+ __be32 alimb;
+#elif BYTES_PER_MPI_LIMB == 8
+ __be64 alimb;
+#else
+#error please implement for this limb size.
+#endif
+ unsigned int n = mpi_get_size(a);
+ struct sg_mapping_iter miter;
+ int i, x, buf_len;
+ int nents;
+
+ if (sign)
+ *sign = a->sign;
+
+ if (nbytes < n)
+ return -EOVERFLOW;
+
+ nents = sg_nents_for_len(sgl, nbytes);
+ if (nents < 0)
+ return -EINVAL;
+
+ sg_miter_start(&miter, sgl, nents, SG_MITER_ATOMIC | SG_MITER_TO_SG);
+ sg_miter_next(&miter);
+ buf_len = miter.length;
+ p2 = miter.addr;
+
+ while (nbytes > n) {
+ i = min_t(unsigned, nbytes - n, buf_len);
+ memset(p2, 0, i);
+ p2 += i;
+ nbytes -= i;
+
+ buf_len -= i;
+ if (!buf_len) {
+ sg_miter_next(&miter);
+ buf_len = miter.length;
+ p2 = miter.addr;
+ }
+ }
+
+ for (i = a->nlimbs - 1; i >= 0; i--) {
+#if BYTES_PER_MPI_LIMB == 4
+ alimb = a->d[i] ? cpu_to_be32(a->d[i]) : 0;
+#elif BYTES_PER_MPI_LIMB == 8
+ alimb = a->d[i] ? cpu_to_be64(a->d[i]) : 0;
+#else
+#error please implement for this limb size.
+#endif
+ p = (u8 *)&alimb;
+
+ for (x = 0; x < sizeof(alimb); x++) {
+ *p2++ = *p++;
+ if (!--buf_len) {
+ sg_miter_next(&miter);
+ buf_len = miter.length;
+ p2 = miter.addr;
+ }
+ }
+ }
+
+ sg_miter_stop(&miter);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(mpi_write_to_sgl);
+
+/*
+ * mpi_read_raw_from_sgl() - Function allocates an MPI and populates it with
+ * data from the sgl
+ *
+ * This function works in the same way as the mpi_read_raw_data, but it
+ * takes an sgl instead of void * buffer. i.e. it allocates
+ * a new MPI and reads the content of the sgl to the MPI.
+ *
+ * @sgl: scatterlist to read from
+ * @nbytes: number of bytes to read
+ *
+ * Return: Pointer to a new MPI or NULL on error
+ */
+MPI mpi_read_raw_from_sgl(struct scatterlist *sgl, unsigned int nbytes)
+{
+ struct sg_mapping_iter miter;
+ unsigned int nbits, nlimbs;
+ int x, j, z, lzeros, ents;
+ unsigned int len;
+ const u8 *buff;
+ mpi_limb_t a;
+ MPI val = NULL;
+
+ ents = sg_nents_for_len(sgl, nbytes);
+ if (ents < 0)
+ return NULL;
+
+ sg_miter_start(&miter, sgl, ents, SG_MITER_ATOMIC | SG_MITER_FROM_SG);
+
+ lzeros = 0;
+ len = 0;
+ while (nbytes > 0) {
+ while (len && !*buff) {
+ lzeros++;
+ len--;
+ buff++;
+ }
+
+ if (len && *buff)
+ break;
+
+ sg_miter_next(&miter);
+ buff = miter.addr;
+ len = miter.length;
+
+ nbytes -= lzeros;
+ lzeros = 0;
+ }
+
+ miter.consumed = lzeros;
+
+ nbytes -= lzeros;
+ nbits = nbytes * 8;
+ if (nbits > MAX_EXTERN_MPI_BITS) {
+ sg_miter_stop(&miter);
+ pr_info("MPI: mpi too large (%u bits)\n", nbits);
+ return NULL;
+ }
+
+ if (nbytes > 0)
+ nbits -= count_leading_zeros(*buff) - (BITS_PER_LONG - 8);
+
+ sg_miter_stop(&miter);
+
+ nlimbs = DIV_ROUND_UP(nbytes, BYTES_PER_MPI_LIMB);
+ val = mpi_alloc(nlimbs);
+ if (!val)
+ return NULL;
+
+ val->nbits = nbits;
+ val->sign = 0;
+ val->nlimbs = nlimbs;
+
+ if (nbytes == 0)
+ return val;
+
+ j = nlimbs - 1;
+ a = 0;
+ z = BYTES_PER_MPI_LIMB - nbytes % BYTES_PER_MPI_LIMB;
+ z %= BYTES_PER_MPI_LIMB;
+
+ while (sg_miter_next(&miter)) {
+ buff = miter.addr;
+ len = min_t(unsigned, miter.length, nbytes);
+ nbytes -= len;
+
+ for (x = 0; x < len; x++) {
+ a <<= 8;
+ a |= *buff++;
+ if (((z + x + 1) % BYTES_PER_MPI_LIMB) == 0) {
+ val->d[j--] = a;
+ a = 0;
+ }
+ }
+ z += x;
+ }
+
+ return val;
+}
+EXPORT_SYMBOL_GPL(mpi_read_raw_from_sgl);
+
+/* Perform a two's complement operation on buffer P of size N bytes. */
+static void twocompl(unsigned char *p, unsigned int n)
+{
+ int i;
+
+ for (i = n-1; i >= 0 && !p[i]; i--)
+ ;
+ if (i >= 0) {
+ if ((p[i] & 0x01))
+ p[i] = (((p[i] ^ 0xfe) | 0x01) & 0xff);
+ else if ((p[i] & 0x02))
+ p[i] = (((p[i] ^ 0xfc) | 0x02) & 0xfe);
+ else if ((p[i] & 0x04))
+ p[i] = (((p[i] ^ 0xf8) | 0x04) & 0xfc);
+ else if ((p[i] & 0x08))
+ p[i] = (((p[i] ^ 0xf0) | 0x08) & 0xf8);
+ else if ((p[i] & 0x10))
+ p[i] = (((p[i] ^ 0xe0) | 0x10) & 0xf0);
+ else if ((p[i] & 0x20))
+ p[i] = (((p[i] ^ 0xc0) | 0x20) & 0xe0);
+ else if ((p[i] & 0x40))
+ p[i] = (((p[i] ^ 0x80) | 0x40) & 0xc0);
+ else
+ p[i] = 0x80;
+
+ for (i--; i >= 0; i--)
+ p[i] ^= 0xff;
+ }
+}
+
+int mpi_print(enum gcry_mpi_format format, unsigned char *buffer,
+ size_t buflen, size_t *nwritten, MPI a)
+{
+ unsigned int nbits = mpi_get_nbits(a);
+ size_t len;
+ size_t dummy_nwritten;
+ int negative;
+
+ if (!nwritten)
+ nwritten = &dummy_nwritten;
+
+ /* Libgcrypt does no always care to set clear the sign if the value
+ * is 0. For printing this is a bit of a surprise, in particular
+ * because if some of the formats don't support negative numbers but
+ * should be able to print a zero. Thus we need this extra test
+ * for a negative number.
+ */
+ if (a->sign && mpi_cmp_ui(a, 0))
+ negative = 1;
+ else
+ negative = 0;
+
+ len = buflen;
+ *nwritten = 0;
+ if (format == GCRYMPI_FMT_STD) {
+ unsigned char *tmp;
+ int extra = 0;
+ unsigned int n;
+
+ tmp = mpi_get_buffer(a, &n, NULL);
+ if (!tmp)
+ return -EINVAL;
+
+ if (negative) {
+ twocompl(tmp, n);
+ if (!(*tmp & 0x80)) {
+ /* Need to extend the sign. */
+ n++;
+ extra = 2;
+ }
+ } else if (n && (*tmp & 0x80)) {
+ /* Positive but the high bit of the returned buffer is set.
+ * Thus we need to print an extra leading 0x00 so that the
+ * output is interpreted as a positive number.
+ */
+ n++;
+ extra = 1;
+ }
+
+ if (buffer && n > len) {
+ /* The provided buffer is too short. */
+ kfree(tmp);
+ return -E2BIG;
+ }
+ if (buffer) {
+ unsigned char *s = buffer;
+
+ if (extra == 1)
+ *s++ = 0;
+ else if (extra)
+ *s++ = 0xff;
+ memcpy(s, tmp, n-!!extra);
+ }
+ kfree(tmp);
+ *nwritten = n;
+ return 0;
+ } else if (format == GCRYMPI_FMT_USG) {
+ unsigned int n = (nbits + 7)/8;
+
+ /* Note: We ignore the sign for this format. */
+ /* FIXME: for performance reasons we should put this into
+ * mpi_aprint because we can then use the buffer directly.
+ */
+
+ if (buffer && n > len)
+ return -E2BIG;
+ if (buffer) {
+ unsigned char *tmp;
+
+ tmp = mpi_get_buffer(a, &n, NULL);
+ if (!tmp)
+ return -EINVAL;
+ memcpy(buffer, tmp, n);
+ kfree(tmp);
+ }
+ *nwritten = n;
+ return 0;
+ } else if (format == GCRYMPI_FMT_PGP) {
+ unsigned int n = (nbits + 7)/8;
+
+ /* The PGP format can only handle unsigned integers. */
+ if (negative)
+ return -EINVAL;
+
+ if (buffer && n+2 > len)
+ return -E2BIG;
+
+ if (buffer) {
+ unsigned char *tmp;
+ unsigned char *s = buffer;
+
+ s[0] = nbits >> 8;
+ s[1] = nbits;
+
+ tmp = mpi_get_buffer(a, &n, NULL);
+ if (!tmp)
+ return -EINVAL;
+ memcpy(s+2, tmp, n);
+ kfree(tmp);
+ }
+ *nwritten = n+2;
+ return 0;
+ } else if (format == GCRYMPI_FMT_SSH) {
+ unsigned char *tmp;
+ int extra = 0;
+ unsigned int n;
+
+ tmp = mpi_get_buffer(a, &n, NULL);
+ if (!tmp)
+ return -EINVAL;
+
+ if (negative) {
+ twocompl(tmp, n);
+ if (!(*tmp & 0x80)) {
+ /* Need to extend the sign. */
+ n++;
+ extra = 2;
+ }
+ } else if (n && (*tmp & 0x80)) {
+ n++;
+ extra = 1;
+ }
+
+ if (buffer && n+4 > len) {
+ kfree(tmp);
+ return -E2BIG;
+ }
+
+ if (buffer) {
+ unsigned char *s = buffer;
+
+ *s++ = n >> 24;
+ *s++ = n >> 16;
+ *s++ = n >> 8;
+ *s++ = n;
+ if (extra == 1)
+ *s++ = 0;
+ else if (extra)
+ *s++ = 0xff;
+ memcpy(s, tmp, n-!!extra);
+ }
+ kfree(tmp);
+ *nwritten = 4+n;
+ return 0;
+ } else if (format == GCRYMPI_FMT_HEX) {
+ unsigned char *tmp;
+ int i;
+ int extra = 0;
+ unsigned int n = 0;
+
+ tmp = mpi_get_buffer(a, &n, NULL);
+ if (!tmp)
+ return -EINVAL;
+ if (!n || (*tmp & 0x80))
+ extra = 2;
+
+ if (buffer && 2*n + extra + negative + 1 > len) {
+ kfree(tmp);
+ return -E2BIG;
+ }
+ if (buffer) {
+ unsigned char *s = buffer;
+
+ if (negative)
+ *s++ = '-';
+ if (extra) {
+ *s++ = '0';
+ *s++ = '0';
+ }
+
+ for (i = 0; i < n; i++) {
+ unsigned int c = tmp[i];
+
+ *s++ = (c >> 4) < 10 ? '0'+(c>>4) : 'A'+(c>>4)-10;
+ c &= 15;
+ *s++ = c < 10 ? '0'+c : 'A'+c-10;
+ }
+ *s++ = 0;
+ *nwritten = s - buffer;
+ } else {
+ *nwritten = 2*n + extra + negative + 1;
+ }
+ kfree(tmp);
+ return 0;
+ } else
+ return -EINVAL;
+}
+EXPORT_SYMBOL_GPL(mpi_print);
diff --git a/lib/mpi/mpih-cmp.c b/lib/mpi/mpih-cmp.c
new file mode 100644
index 000000000..f23709114
--- /dev/null
+++ b/lib/mpi/mpih-cmp.c
@@ -0,0 +1,43 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* mpihelp-sub.c - MPI helper 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.
+ *
+ * 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"
+
+/****************
+ * Compare OP1_PTR/OP1_SIZE with OP2_PTR/OP2_SIZE.
+ * There are no restrictions on the relative sizes of
+ * the two arguments.
+ * Return 1 if OP1 > OP2, 0 if they are equal, and -1 if OP1 < OP2.
+ */
+int mpihelp_cmp(mpi_ptr_t op1_ptr, mpi_ptr_t op2_ptr, mpi_size_t size)
+{
+ mpi_size_t i;
+ mpi_limb_t op1_word, op2_word;
+
+ for (i = size - 1; i >= 0; i--) {
+ op1_word = op1_ptr[i];
+ op2_word = op2_ptr[i];
+ if (op1_word != op2_word)
+ goto diff;
+ }
+ return 0;
+
+diff:
+ /* This can *not* be simplified to
+ * op2_word - op2_word
+ * since that expression might give signed overflow. */
+ return (op1_word > op2_word) ? 1 : -1;
+}
diff --git a/lib/mpi/mpih-div.c b/lib/mpi/mpih-div.c
new file mode 100644
index 000000000..be70ee2e4
--- /dev/null
+++ b/lib/mpi/mpih-div.c
@@ -0,0 +1,517 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* mpihelp-div.c - MPI helper functions
+ * Copyright (C) 1994, 1996 Free Software Foundation, Inc.
+ * Copyright (C) 1998, 1999 Free Software Foundation, Inc.
+ *
+ * This file is part of GnuPG.
+ *
+ * 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"
+#include "longlong.h"
+
+#ifndef UMUL_TIME
+#define UMUL_TIME 1
+#endif
+#ifndef UDIV_TIME
+#define UDIV_TIME UMUL_TIME
+#endif
+
+
+mpi_limb_t
+mpihelp_mod_1(mpi_ptr_t dividend_ptr, mpi_size_t dividend_size,
+ mpi_limb_t divisor_limb)
+{
+ mpi_size_t i;
+ mpi_limb_t n1, n0, r;
+ mpi_limb_t dummy __maybe_unused;
+
+ /* Botch: Should this be handled at all? Rely on callers? */
+ if (!dividend_size)
+ return 0;
+
+ /* If multiplication is much faster than division, and the
+ * dividend is large, pre-invert the divisor, and use
+ * only multiplications in the inner loop.
+ *
+ * This test should be read:
+ * Does it ever help to use udiv_qrnnd_preinv?
+ * && Does what we save compensate for the inversion overhead?
+ */
+ if (UDIV_TIME > (2 * UMUL_TIME + 6)
+ && (UDIV_TIME - (2 * UMUL_TIME + 6)) * dividend_size > UDIV_TIME) {
+ int normalization_steps;
+
+ normalization_steps = count_leading_zeros(divisor_limb);
+ if (normalization_steps) {
+ mpi_limb_t divisor_limb_inverted;
+
+ divisor_limb <<= normalization_steps;
+
+ /* Compute (2**2N - 2**N * DIVISOR_LIMB) / DIVISOR_LIMB. The
+ * result is a (N+1)-bit approximation to 1/DIVISOR_LIMB, with the
+ * most significant bit (with weight 2**N) implicit.
+ *
+ * Special case for DIVISOR_LIMB == 100...000.
+ */
+ if (!(divisor_limb << 1))
+ divisor_limb_inverted = ~(mpi_limb_t)0;
+ else
+ udiv_qrnnd(divisor_limb_inverted, dummy,
+ -divisor_limb, 0, divisor_limb);
+
+ n1 = dividend_ptr[dividend_size - 1];
+ r = n1 >> (BITS_PER_MPI_LIMB - normalization_steps);
+
+ /* Possible optimization:
+ * if (r == 0
+ * && divisor_limb > ((n1 << normalization_steps)
+ * | (dividend_ptr[dividend_size - 2] >> ...)))
+ * ...one division less...
+ */
+ for (i = dividend_size - 2; i >= 0; i--) {
+ n0 = dividend_ptr[i];
+ UDIV_QRNND_PREINV(dummy, r, r,
+ ((n1 << normalization_steps)
+ | (n0 >> (BITS_PER_MPI_LIMB - normalization_steps))),
+ divisor_limb, divisor_limb_inverted);
+ n1 = n0;
+ }
+ UDIV_QRNND_PREINV(dummy, r, r,
+ n1 << normalization_steps,
+ divisor_limb, divisor_limb_inverted);
+ return r >> normalization_steps;
+ } else {
+ mpi_limb_t divisor_limb_inverted;
+
+ /* Compute (2**2N - 2**N * DIVISOR_LIMB) / DIVISOR_LIMB. The
+ * result is a (N+1)-bit approximation to 1/DIVISOR_LIMB, with the
+ * most significant bit (with weight 2**N) implicit.
+ *
+ * Special case for DIVISOR_LIMB == 100...000.
+ */
+ if (!(divisor_limb << 1))
+ divisor_limb_inverted = ~(mpi_limb_t)0;
+ else
+ udiv_qrnnd(divisor_limb_inverted, dummy,
+ -divisor_limb, 0, divisor_limb);
+
+ i = dividend_size - 1;
+ r = dividend_ptr[i];
+
+ if (r >= divisor_limb)
+ r = 0;
+ else
+ i--;
+
+ for ( ; i >= 0; i--) {
+ n0 = dividend_ptr[i];
+ UDIV_QRNND_PREINV(dummy, r, r,
+ n0, divisor_limb, divisor_limb_inverted);
+ }
+ return r;
+ }
+ } else {
+ if (UDIV_NEEDS_NORMALIZATION) {
+ int normalization_steps;
+
+ normalization_steps = count_leading_zeros(divisor_limb);
+ if (normalization_steps) {
+ divisor_limb <<= normalization_steps;
+
+ n1 = dividend_ptr[dividend_size - 1];
+ r = n1 >> (BITS_PER_MPI_LIMB - normalization_steps);
+
+ /* Possible optimization:
+ * if (r == 0
+ * && divisor_limb > ((n1 << normalization_steps)
+ * | (dividend_ptr[dividend_size - 2] >> ...)))
+ * ...one division less...
+ */
+ for (i = dividend_size - 2; i >= 0; i--) {
+ n0 = dividend_ptr[i];
+ udiv_qrnnd(dummy, r, r,
+ ((n1 << normalization_steps)
+ | (n0 >> (BITS_PER_MPI_LIMB - normalization_steps))),
+ divisor_limb);
+ n1 = n0;
+ }
+ udiv_qrnnd(dummy, r, r,
+ n1 << normalization_steps,
+ divisor_limb);
+ return r >> normalization_steps;
+ }
+ }
+ /* No normalization needed, either because udiv_qrnnd doesn't require
+ * it, or because DIVISOR_LIMB is already normalized.
+ */
+ i = dividend_size - 1;
+ r = dividend_ptr[i];
+
+ if (r >= divisor_limb)
+ r = 0;
+ else
+ i--;
+
+ for (; i >= 0; i--) {
+ n0 = dividend_ptr[i];
+ udiv_qrnnd(dummy, r, r, n0, divisor_limb);
+ }
+ return r;
+ }
+}
+
+/* Divide num (NP/NSIZE) by den (DP/DSIZE) and write
+ * the NSIZE-DSIZE least significant quotient limbs at QP
+ * and the DSIZE long remainder at NP. If QEXTRA_LIMBS is
+ * non-zero, generate that many fraction bits and append them after the
+ * other quotient limbs.
+ * Return the most significant limb of the quotient, this is always 0 or 1.
+ *
+ * Preconditions:
+ * 0. NSIZE >= DSIZE.
+ * 1. The most significant bit of the divisor must be set.
+ * 2. QP must either not overlap with the input operands at all, or
+ * QP + DSIZE >= NP must hold true. (This means that it's
+ * possible to put the quotient in the high part of NUM, right after the
+ * remainder in NUM.
+ * 3. NSIZE >= DSIZE, even if QEXTRA_LIMBS is non-zero.
+ */
+
+mpi_limb_t
+mpihelp_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 most_significant_q_limb = 0;
+
+ switch (dsize) {
+ case 0:
+ /* We are asked to divide by zero, so go ahead and do it! (To make
+ the compiler not remove this statement, return the value.) */
+ /*
+ * existing clients of this function have been modified
+ * not to call it with dsize == 0, so this should not happen
+ */
+ return 1 / dsize;
+
+ case 1:
+ {
+ mpi_size_t i;
+ mpi_limb_t n1;
+ mpi_limb_t d;
+
+ d = dp[0];
+ n1 = np[nsize - 1];
+
+ if (n1 >= d) {
+ n1 -= d;
+ most_significant_q_limb = 1;
+ }
+
+ qp += qextra_limbs;
+ for (i = nsize - 2; i >= 0; i--)
+ udiv_qrnnd(qp[i], n1, n1, np[i], d);
+ qp -= qextra_limbs;
+
+ for (i = qextra_limbs - 1; i >= 0; i--)
+ udiv_qrnnd(qp[i], n1, n1, 0, d);
+
+ np[0] = n1;
+ }
+ break;
+
+ case 2:
+ {
+ mpi_size_t i;
+ mpi_limb_t n1, n0, n2;
+ mpi_limb_t d1, d0;
+
+ np += nsize - 2;
+ d1 = dp[1];
+ d0 = dp[0];
+ n1 = np[1];
+ n0 = np[0];
+
+ if (n1 >= d1 && (n1 > d1 || n0 >= d0)) {
+ sub_ddmmss(n1, n0, n1, n0, d1, d0);
+ most_significant_q_limb = 1;
+ }
+
+ for (i = qextra_limbs + nsize - 2 - 1; i >= 0; i--) {
+ mpi_limb_t q;
+ mpi_limb_t r;
+
+ if (i >= qextra_limbs)
+ np--;
+ else
+ np[0] = 0;
+
+ if (n1 == d1) {
+ /* Q should be either 111..111 or 111..110. Need special
+ * treatment of this rare case as normal division would
+ * give overflow. */
+ q = ~(mpi_limb_t) 0;
+
+ r = n0 + d1;
+ if (r < d1) { /* Carry in the addition? */
+ add_ssaaaa(n1, n0, r - d0,
+ np[0], 0, d0);
+ qp[i] = q;
+ continue;
+ }
+ n1 = d0 - (d0 != 0 ? 1 : 0);
+ n0 = -d0;
+ } else {
+ udiv_qrnnd(q, r, n1, n0, d1);
+ umul_ppmm(n1, n0, d0, q);
+ }
+
+ n2 = np[0];
+q_test:
+ if (n1 > r || (n1 == r && n0 > n2)) {
+ /* The estimated Q was too large. */
+ q--;
+ sub_ddmmss(n1, n0, n1, n0, 0, d0);
+ r += d1;
+ if (r >= d1) /* If not carry, test Q again. */
+ goto q_test;
+ }
+
+ qp[i] = q;
+ sub_ddmmss(n1, n0, r, n2, n1, n0);
+ }
+ np[1] = n1;
+ np[0] = n0;
+ }
+ break;
+
+ default:
+ {
+ mpi_size_t i;
+ mpi_limb_t dX, d1, n0;
+
+ np += nsize - dsize;
+ dX = dp[dsize - 1];
+ d1 = dp[dsize - 2];
+ n0 = np[dsize - 1];
+
+ if (n0 >= dX) {
+ if (n0 > dX
+ || mpihelp_cmp(np, dp, dsize - 1) >= 0) {
+ mpihelp_sub_n(np, np, dp, dsize);
+ n0 = np[dsize - 1];
+ most_significant_q_limb = 1;
+ }
+ }
+
+ for (i = qextra_limbs + nsize - dsize - 1; i >= 0; i--) {
+ mpi_limb_t q;
+ mpi_limb_t n1, n2;
+ mpi_limb_t cy_limb;
+
+ if (i >= qextra_limbs) {
+ np--;
+ n2 = np[dsize];
+ } else {
+ n2 = np[dsize - 1];
+ MPN_COPY_DECR(np + 1, np, dsize - 1);
+ np[0] = 0;
+ }
+
+ if (n0 == dX) {
+ /* This might over-estimate q, but it's probably not worth
+ * the extra code here to find out. */
+ q = ~(mpi_limb_t) 0;
+ } else {
+ mpi_limb_t r;
+
+ udiv_qrnnd(q, r, n0, np[dsize - 1], dX);
+ umul_ppmm(n1, n0, d1, q);
+
+ while (n1 > r
+ || (n1 == r
+ && n0 > np[dsize - 2])) {
+ q--;
+ r += dX;
+ if (r < dX) /* I.e. "carry in previous addition?" */
+ break;
+ n1 -= n0 < d1;
+ n0 -= d1;
+ }
+ }
+
+ /* Possible optimization: We already have (q * n0) and (1 * n1)
+ * after the calculation of q. Taking advantage of that, we
+ * could make this loop make two iterations less. */
+ cy_limb = mpihelp_submul_1(np, dp, dsize, q);
+
+ if (n2 != cy_limb) {
+ mpihelp_add_n(np, np, dp, dsize);
+ q--;
+ }
+
+ qp[i] = q;
+ n0 = np[dsize - 1];
+ }
+ }
+ }
+
+ return most_significant_q_limb;
+}
+
+/****************
+ * Divide (DIVIDEND_PTR,,DIVIDEND_SIZE) by DIVISOR_LIMB.
+ * Write DIVIDEND_SIZE limbs of quotient at QUOT_PTR.
+ * Return the single-limb remainder.
+ * There are no constraints on the value of the divisor.
+ *
+ * QUOT_PTR and DIVIDEND_PTR might point to the same limb.
+ */
+
+mpi_limb_t
+mpihelp_divmod_1(mpi_ptr_t quot_ptr,
+ mpi_ptr_t dividend_ptr, mpi_size_t dividend_size,
+ mpi_limb_t divisor_limb)
+{
+ mpi_size_t i;
+ mpi_limb_t n1, n0, r;
+ mpi_limb_t dummy __maybe_unused;
+
+ if (!dividend_size)
+ return 0;
+
+ /* If multiplication is much faster than division, and the
+ * dividend is large, pre-invert the divisor, and use
+ * only multiplications in the inner loop.
+ *
+ * This test should be read:
+ * Does it ever help to use udiv_qrnnd_preinv?
+ * && Does what we save compensate for the inversion overhead?
+ */
+ if (UDIV_TIME > (2 * UMUL_TIME + 6)
+ && (UDIV_TIME - (2 * UMUL_TIME + 6)) * dividend_size > UDIV_TIME) {
+ int normalization_steps;
+
+ normalization_steps = count_leading_zeros(divisor_limb);
+ if (normalization_steps) {
+ mpi_limb_t divisor_limb_inverted;
+
+ divisor_limb <<= normalization_steps;
+
+ /* Compute (2**2N - 2**N * DIVISOR_LIMB) / DIVISOR_LIMB. The
+ * result is a (N+1)-bit approximation to 1/DIVISOR_LIMB, with the
+ * most significant bit (with weight 2**N) implicit.
+ */
+ /* Special case for DIVISOR_LIMB == 100...000. */
+ if (!(divisor_limb << 1))
+ divisor_limb_inverted = ~(mpi_limb_t)0;
+ else
+ udiv_qrnnd(divisor_limb_inverted, dummy,
+ -divisor_limb, 0, divisor_limb);
+
+ n1 = dividend_ptr[dividend_size - 1];
+ r = n1 >> (BITS_PER_MPI_LIMB - normalization_steps);
+
+ /* Possible optimization:
+ * if (r == 0
+ * && divisor_limb > ((n1 << normalization_steps)
+ * | (dividend_ptr[dividend_size - 2] >> ...)))
+ * ...one division less...
+ */
+ for (i = dividend_size - 2; i >= 0; i--) {
+ n0 = dividend_ptr[i];
+ UDIV_QRNND_PREINV(quot_ptr[i + 1], r, r,
+ ((n1 << normalization_steps)
+ | (n0 >> (BITS_PER_MPI_LIMB - normalization_steps))),
+ divisor_limb, divisor_limb_inverted);
+ n1 = n0;
+ }
+ UDIV_QRNND_PREINV(quot_ptr[0], r, r,
+ n1 << normalization_steps,
+ divisor_limb, divisor_limb_inverted);
+ return r >> normalization_steps;
+ } else {
+ mpi_limb_t divisor_limb_inverted;
+
+ /* Compute (2**2N - 2**N * DIVISOR_LIMB) / DIVISOR_LIMB. The
+ * result is a (N+1)-bit approximation to 1/DIVISOR_LIMB, with the
+ * most significant bit (with weight 2**N) implicit.
+ */
+ /* Special case for DIVISOR_LIMB == 100...000. */
+ if (!(divisor_limb << 1))
+ divisor_limb_inverted = ~(mpi_limb_t) 0;
+ else
+ udiv_qrnnd(divisor_limb_inverted, dummy,
+ -divisor_limb, 0, divisor_limb);
+
+ i = dividend_size - 1;
+ r = dividend_ptr[i];
+
+ if (r >= divisor_limb)
+ r = 0;
+ else
+ quot_ptr[i--] = 0;
+
+ for ( ; i >= 0; i--) {
+ n0 = dividend_ptr[i];
+ UDIV_QRNND_PREINV(quot_ptr[i], r, r,
+ n0, divisor_limb, divisor_limb_inverted);
+ }
+ return r;
+ }
+ } else {
+ if (UDIV_NEEDS_NORMALIZATION) {
+ int normalization_steps;
+
+ normalization_steps = count_leading_zeros(divisor_limb);
+ if (normalization_steps) {
+ divisor_limb <<= normalization_steps;
+
+ n1 = dividend_ptr[dividend_size - 1];
+ r = n1 >> (BITS_PER_MPI_LIMB - normalization_steps);
+
+ /* Possible optimization:
+ * if (r == 0
+ * && divisor_limb > ((n1 << normalization_steps)
+ * | (dividend_ptr[dividend_size - 2] >> ...)))
+ * ...one division less...
+ */
+ for (i = dividend_size - 2; i >= 0; i--) {
+ n0 = dividend_ptr[i];
+ udiv_qrnnd(quot_ptr[i + 1], r, r,
+ ((n1 << normalization_steps)
+ | (n0 >> (BITS_PER_MPI_LIMB - normalization_steps))),
+ divisor_limb);
+ n1 = n0;
+ }
+ udiv_qrnnd(quot_ptr[0], r, r,
+ n1 << normalization_steps,
+ divisor_limb);
+ return r >> normalization_steps;
+ }
+ }
+ /* No normalization needed, either because udiv_qrnnd doesn't require
+ * it, or because DIVISOR_LIMB is already normalized.
+ */
+ i = dividend_size - 1;
+ r = dividend_ptr[i];
+
+ if (r >= divisor_limb)
+ r = 0;
+ else
+ quot_ptr[i--] = 0;
+
+ for (; i >= 0; i--) {
+ n0 = dividend_ptr[i];
+ udiv_qrnnd(quot_ptr[i], r, r, n0, divisor_limb);
+ }
+ return r;
+ }
+}
diff --git a/lib/mpi/mpih-mul.c b/lib/mpi/mpih-mul.c
new file mode 100644
index 000000000..e5f1c84e3
--- /dev/null
+++ b/lib/mpi/mpih-mul.c
@@ -0,0 +1,509 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* mpihelp-mul.c - MPI helper functions
+ * Copyright (C) 1994, 1996, 1998, 1999,
+ * 2000 Free Software Foundation, Inc.
+ *
+ * This file is part of GnuPG.
+ *
+ * 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"
+
+#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);
+
+#define MPN_SQR_N_RECURSE(prodp, up, size, tspace) \
+ do { \
+ if ((size) < KARATSUBA_THRESHOLD) \
+ mpih_sqr_n_basecase(prodp, up, size); \
+ else \
+ mpih_sqr_n(prodp, up, size, tspace); \
+ } while (0);
+
+/* Multiply the natural numbers u (pointed to by UP) and v (pointed to by VP),
+ * both with SIZE limbs, and store the result at PRODP. 2 * SIZE limbs are
+ * always stored. Return the most significant limb.
+ *
+ * Argument constraints:
+ * 1. PRODP != UP and PRODP != VP, i.e. the destination
+ * must be distinct from the multiplier and the multiplicand.
+ *
+ *
+ * Handle simple cases with traditional multiplication.
+ *
+ * This is the most critical code of multiplication. All multiplies rely
+ * on this, both small and huge. Small ones arrive here immediately. Huge
+ * ones arrive here as this is the base case for Karatsuba's recursive
+ * algorithm below.
+ */
+
+static mpi_limb_t
+mul_n_basecase(mpi_ptr_t prodp, mpi_ptr_t up, mpi_ptr_t vp, mpi_size_t size)
+{
+ mpi_size_t i;
+ mpi_limb_t cy;
+ mpi_limb_t v_limb;
+
+ /* Multiply by the first limb in V separately, as the result can be
+ * stored (not added) to PROD. We also avoid a loop for zeroing. */
+ v_limb = vp[0];
+ if (v_limb <= 1) {
+ if (v_limb == 1)
+ MPN_COPY(prodp, up, size);
+ else
+ MPN_ZERO(prodp, size);
+ cy = 0;
+ } else
+ cy = mpihelp_mul_1(prodp, up, size, v_limb);
+
+ prodp[size] = cy;
+ prodp++;
+
+ /* For each iteration in the outer loop, multiply one limb from
+ * U with one limb from V, and add it to PROD. */
+ for (i = 1; i < size; i++) {
+ v_limb = vp[i];
+ if (v_limb <= 1) {
+ cy = 0;
+ if (v_limb == 1)
+ cy = mpihelp_add_n(prodp, prodp, up, size);
+ } else
+ cy = mpihelp_addmul_1(prodp, up, size, v_limb);
+
+ prodp[size] = cy;
+ prodp++;
+ }
+
+ return cy;
+}
+
+static void
+mul_n(mpi_ptr_t prodp, mpi_ptr_t up, mpi_ptr_t vp,
+ mpi_size_t size, mpi_ptr_t tspace)
+{
+ if (size & 1) {
+ /* The size is odd, and the code below doesn't handle that.
+ * Multiply the least significant (size - 1) limbs with a recursive
+ * call, and handle the most significant limb of S1 and S2
+ * separately.
+ * A slightly faster way to do this would be to make the Karatsuba
+ * code below behave as if the size were even, and let it check for
+ * odd size in the end. I.e., in essence move this code to the end.
+ * Doing so would save us a recursive call, and potentially make the
+ * stack grow a lot less.
+ */
+ mpi_size_t esize = size - 1; /* even size */
+ mpi_limb_t cy_limb;
+
+ MPN_MUL_N_RECURSE(prodp, up, vp, esize, tspace);
+ cy_limb = mpihelp_addmul_1(prodp + esize, up, esize, vp[esize]);
+ prodp[esize + esize] = cy_limb;
+ cy_limb = mpihelp_addmul_1(prodp + esize, vp, size, up[esize]);
+ prodp[esize + size] = cy_limb;
+ } else {
+ /* Anatolij Alekseevich Karatsuba's divide-and-conquer algorithm.
+ *
+ * Split U in two pieces, U1 and U0, such that
+ * U = U0 + U1*(B**n),
+ * and V in V1 and V0, such that
+ * V = V0 + V1*(B**n).
+ *
+ * UV is then computed recursively using the identity
+ *
+ * 2n n n n
+ * UV = (B + B )U V + B (U -U )(V -V ) + (B + 1)U V
+ * 1 1 1 0 0 1 0 0
+ *
+ * Where B = 2**BITS_PER_MP_LIMB.
+ */
+ mpi_size_t hsize = size >> 1;
+ mpi_limb_t cy;
+ int negflg;
+
+ /* Product H. ________________ ________________
+ * |_____U1 x V1____||____U0 x V0_____|
+ * Put result in upper part of PROD and pass low part of TSPACE
+ * as new TSPACE.
+ */
+ MPN_MUL_N_RECURSE(prodp + size, up + hsize, vp + hsize, hsize,
+ tspace);
+
+ /* Product M. ________________
+ * |_(U1-U0)(V0-V1)_|
+ */
+ if (mpihelp_cmp(up + hsize, up, hsize) >= 0) {
+ mpihelp_sub_n(prodp, up + hsize, up, hsize);
+ negflg = 0;
+ } else {
+ mpihelp_sub_n(prodp, up, up + hsize, hsize);
+ negflg = 1;
+ }
+ if (mpihelp_cmp(vp + hsize, vp, hsize) >= 0) {
+ mpihelp_sub_n(prodp + hsize, vp + hsize, vp, hsize);
+ negflg ^= 1;
+ } else {
+ mpihelp_sub_n(prodp + hsize, vp, vp + hsize, hsize);
+ /* No change of NEGFLG. */
+ }
+ /* Read temporary operands from low part of PROD.
+ * Put result in low part of TSPACE using upper part of TSPACE
+ * as new TSPACE.
+ */
+ MPN_MUL_N_RECURSE(tspace, prodp, prodp + hsize, hsize,
+ tspace + size);
+
+ /* Add/copy product H. */
+ MPN_COPY(prodp + hsize, prodp + size, hsize);
+ cy = mpihelp_add_n(prodp + size, prodp + size,
+ prodp + size + hsize, hsize);
+
+ /* Add product M (if NEGFLG M is a negative number) */
+ if (negflg)
+ cy -=
+ mpihelp_sub_n(prodp + hsize, prodp + hsize, tspace,
+ size);
+ else
+ cy +=
+ mpihelp_add_n(prodp + hsize, prodp + hsize, tspace,
+ size);
+
+ /* Product L. ________________ ________________
+ * |________________||____U0 x V0_____|
+ * Read temporary operands from low part of PROD.
+ * Put result in low part of TSPACE using upper part of TSPACE
+ * as new TSPACE.
+ */
+ MPN_MUL_N_RECURSE(tspace, up, vp, hsize, tspace + size);
+
+ /* Add/copy Product L (twice) */
+
+ cy += mpihelp_add_n(prodp + hsize, prodp + hsize, tspace, size);
+ if (cy)
+ mpihelp_add_1(prodp + hsize + size,
+ prodp + hsize + size, hsize, cy);
+
+ MPN_COPY(prodp, tspace, hsize);
+ cy = mpihelp_add_n(prodp + hsize, prodp + hsize, tspace + hsize,
+ hsize);
+ if (cy)
+ mpihelp_add_1(prodp + size, prodp + size, size, 1);
+ }
+}
+
+void mpih_sqr_n_basecase(mpi_ptr_t prodp, mpi_ptr_t up, mpi_size_t size)
+{
+ mpi_size_t i;
+ mpi_limb_t cy_limb;
+ mpi_limb_t v_limb;
+
+ /* Multiply by the first limb in V separately, as the result can be
+ * stored (not added) to PROD. We also avoid a loop for zeroing. */
+ v_limb = up[0];
+ if (v_limb <= 1) {
+ if (v_limb == 1)
+ MPN_COPY(prodp, up, size);
+ else
+ MPN_ZERO(prodp, size);
+ cy_limb = 0;
+ } else
+ cy_limb = mpihelp_mul_1(prodp, up, size, v_limb);
+
+ prodp[size] = cy_limb;
+ prodp++;
+
+ /* For each iteration in the outer loop, multiply one limb from
+ * U with one limb from V, and add it to PROD. */
+ for (i = 1; i < size; i++) {
+ v_limb = up[i];
+ if (v_limb <= 1) {
+ cy_limb = 0;
+ if (v_limb == 1)
+ cy_limb = mpihelp_add_n(prodp, prodp, up, size);
+ } else
+ cy_limb = mpihelp_addmul_1(prodp, up, size, v_limb);
+
+ prodp[size] = cy_limb;
+ prodp++;
+ }
+}
+
+void
+mpih_sqr_n(mpi_ptr_t prodp, mpi_ptr_t up, mpi_size_t size, mpi_ptr_t tspace)
+{
+ if (size & 1) {
+ /* The size is odd, and the code below doesn't handle that.
+ * Multiply the least significant (size - 1) limbs with a recursive
+ * call, and handle the most significant limb of S1 and S2
+ * separately.
+ * A slightly faster way to do this would be to make the Karatsuba
+ * code below behave as if the size were even, and let it check for
+ * odd size in the end. I.e., in essence move this code to the end.
+ * Doing so would save us a recursive call, and potentially make the
+ * stack grow a lot less.
+ */
+ mpi_size_t esize = size - 1; /* even size */
+ mpi_limb_t cy_limb;
+
+ MPN_SQR_N_RECURSE(prodp, up, esize, tspace);
+ cy_limb = mpihelp_addmul_1(prodp + esize, up, esize, up[esize]);
+ prodp[esize + esize] = cy_limb;
+ cy_limb = mpihelp_addmul_1(prodp + esize, up, size, up[esize]);
+
+ prodp[esize + size] = cy_limb;
+ } else {
+ mpi_size_t hsize = size >> 1;
+ mpi_limb_t cy;
+
+ /* Product H. ________________ ________________
+ * |_____U1 x U1____||____U0 x U0_____|
+ * Put result in upper part of PROD and pass low part of TSPACE
+ * as new TSPACE.
+ */
+ MPN_SQR_N_RECURSE(prodp + size, up + hsize, hsize, tspace);
+
+ /* Product M. ________________
+ * |_(U1-U0)(U0-U1)_|
+ */
+ if (mpihelp_cmp(up + hsize, up, hsize) >= 0)
+ mpihelp_sub_n(prodp, up + hsize, up, hsize);
+ else
+ mpihelp_sub_n(prodp, up, up + hsize, hsize);
+
+ /* Read temporary operands from low part of PROD.
+ * Put result in low part of TSPACE using upper part of TSPACE
+ * as new TSPACE. */
+ MPN_SQR_N_RECURSE(tspace, prodp, hsize, tspace + size);
+
+ /* Add/copy product H */
+ MPN_COPY(prodp + hsize, prodp + size, hsize);
+ cy = mpihelp_add_n(prodp + size, prodp + size,
+ prodp + size + hsize, hsize);
+
+ /* Add product M (if NEGFLG M is a negative number). */
+ cy -= mpihelp_sub_n(prodp + hsize, prodp + hsize, tspace, size);
+
+ /* Product L. ________________ ________________
+ * |________________||____U0 x U0_____|
+ * Read temporary operands from low part of PROD.
+ * Put result in low part of TSPACE using upper part of TSPACE
+ * as new TSPACE. */
+ MPN_SQR_N_RECURSE(tspace, up, hsize, tspace + size);
+
+ /* Add/copy Product L (twice). */
+ cy += mpihelp_add_n(prodp + hsize, prodp + hsize, tspace, size);
+ if (cy)
+ mpihelp_add_1(prodp + hsize + size,
+ prodp + hsize + size, hsize, cy);
+
+ MPN_COPY(prodp, tspace, hsize);
+ cy = mpihelp_add_n(prodp + hsize, prodp + hsize, tspace + hsize,
+ hsize);
+ if (cy)
+ mpihelp_add_1(prodp + size, prodp + size, size, 1);
+ }
+}
+
+
+void mpihelp_mul_n(mpi_ptr_t prodp,
+ mpi_ptr_t up, mpi_ptr_t vp, mpi_size_t size)
+{
+ if (up == vp) {
+ if (size < KARATSUBA_THRESHOLD)
+ mpih_sqr_n_basecase(prodp, up, size);
+ else {
+ mpi_ptr_t tspace;
+ tspace = mpi_alloc_limb_space(2 * size);
+ mpih_sqr_n(prodp, up, size, tspace);
+ mpi_free_limb_space(tspace);
+ }
+ } else {
+ if (size < KARATSUBA_THRESHOLD)
+ mul_n_basecase(prodp, up, vp, size);
+ else {
+ mpi_ptr_t tspace;
+ tspace = mpi_alloc_limb_space(2 * size);
+ mul_n(prodp, up, vp, size, tspace);
+ mpi_free_limb_space(tspace);
+ }
+ }
+}
+
+int
+mpihelp_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)
+{
+ mpi_limb_t cy;
+
+ if (!ctx->tspace || ctx->tspace_size < vsize) {
+ if (ctx->tspace)
+ mpi_free_limb_space(ctx->tspace);
+ ctx->tspace = mpi_alloc_limb_space(2 * vsize);
+ if (!ctx->tspace)
+ return -ENOMEM;
+ ctx->tspace_size = vsize;
+ }
+
+ MPN_MUL_N_RECURSE(prodp, up, vp, vsize, ctx->tspace);
+
+ prodp += vsize;
+ up += vsize;
+ usize -= vsize;
+ if (usize >= vsize) {
+ if (!ctx->tp || ctx->tp_size < vsize) {
+ if (ctx->tp)
+ mpi_free_limb_space(ctx->tp);
+ ctx->tp = mpi_alloc_limb_space(2 * vsize);
+ if (!ctx->tp) {
+ if (ctx->tspace)
+ mpi_free_limb_space(ctx->tspace);
+ ctx->tspace = NULL;
+ return -ENOMEM;
+ }
+ ctx->tp_size = vsize;
+ }
+
+ do {
+ MPN_MUL_N_RECURSE(ctx->tp, up, vp, vsize, ctx->tspace);
+ cy = mpihelp_add_n(prodp, prodp, ctx->tp, vsize);
+ mpihelp_add_1(prodp + vsize, ctx->tp + vsize, vsize,
+ cy);
+ prodp += vsize;
+ up += vsize;
+ usize -= vsize;
+ } while (usize >= vsize);
+ }
+
+ if (usize) {
+ if (usize < KARATSUBA_THRESHOLD) {
+ mpi_limb_t tmp;
+ if (mpihelp_mul(ctx->tspace, vp, vsize, up, usize, &tmp)
+ < 0)
+ return -ENOMEM;
+ } else {
+ if (!ctx->next) {
+ ctx->next = kzalloc(sizeof *ctx, GFP_KERNEL);
+ if (!ctx->next)
+ return -ENOMEM;
+ }
+ if (mpihelp_mul_karatsuba_case(ctx->tspace,
+ vp, vsize,
+ up, usize,
+ ctx->next) < 0)
+ return -ENOMEM;
+ }
+
+ cy = mpihelp_add_n(prodp, prodp, ctx->tspace, vsize);
+ mpihelp_add_1(prodp + vsize, ctx->tspace + vsize, usize, cy);
+ }
+
+ return 0;
+}
+
+void mpihelp_release_karatsuba_ctx(struct karatsuba_ctx *ctx)
+{
+ struct karatsuba_ctx *ctx2;
+
+ if (ctx->tp)
+ mpi_free_limb_space(ctx->tp);
+ if (ctx->tspace)
+ mpi_free_limb_space(ctx->tspace);
+ for (ctx = ctx->next; ctx; ctx = ctx2) {
+ ctx2 = ctx->next;
+ if (ctx->tp)
+ mpi_free_limb_space(ctx->tp);
+ if (ctx->tspace)
+ mpi_free_limb_space(ctx->tspace);
+ kfree(ctx);
+ }
+}
+
+/* Multiply the natural numbers u (pointed to by UP, with USIZE limbs)
+ * and v (pointed to by VP, with VSIZE limbs), and store the result at
+ * PRODP. USIZE + VSIZE limbs are always stored, but if the input
+ * operands are normalized. Return the most significant limb of the
+ * result.
+ *
+ * NOTE: The space pointed to by PRODP is overwritten before finished
+ * with U and V, so overlap is an error.
+ *
+ * Argument constraints:
+ * 1. USIZE >= VSIZE.
+ * 2. PRODP != UP and PRODP != VP, i.e. the destination
+ * must be distinct from the multiplier and the multiplicand.
+ */
+
+int
+mpihelp_mul(mpi_ptr_t prodp, mpi_ptr_t up, mpi_size_t usize,
+ mpi_ptr_t vp, mpi_size_t vsize, mpi_limb_t *_result)
+{
+ mpi_ptr_t prod_endp = prodp + usize + vsize - 1;
+ mpi_limb_t cy;
+ struct karatsuba_ctx ctx;
+
+ if (vsize < KARATSUBA_THRESHOLD) {
+ mpi_size_t i;
+ mpi_limb_t v_limb;
+
+ if (!vsize) {
+ *_result = 0;
+ return 0;
+ }
+
+ /* Multiply by the first limb in V separately, as the result can be
+ * stored (not added) to PROD. We also avoid a loop for zeroing. */
+ v_limb = vp[0];
+ if (v_limb <= 1) {
+ if (v_limb == 1)
+ MPN_COPY(prodp, up, usize);
+ else
+ MPN_ZERO(prodp, usize);
+ cy = 0;
+ } else
+ cy = mpihelp_mul_1(prodp, up, usize, v_limb);
+
+ prodp[usize] = cy;
+ prodp++;
+
+ /* For each iteration in the outer loop, multiply one limb from
+ * U with one limb from V, and add it to PROD. */
+ for (i = 1; i < vsize; i++) {
+ v_limb = vp[i];
+ if (v_limb <= 1) {
+ cy = 0;
+ if (v_limb == 1)
+ cy = mpihelp_add_n(prodp, prodp, up,
+ usize);
+ } else
+ cy = mpihelp_addmul_1(prodp, up, usize, v_limb);
+
+ prodp[usize] = cy;
+ prodp++;
+ }
+
+ *_result = cy;
+ return 0;
+ }
+
+ memset(&ctx, 0, sizeof ctx);
+ if (mpihelp_mul_karatsuba_case(prodp, up, usize, vp, vsize, &ctx) < 0)
+ return -ENOMEM;
+ mpihelp_release_karatsuba_ctx(&ctx);
+ *_result = *prod_endp;
+ return 0;
+}
diff --git a/lib/mpi/mpiutil.c b/lib/mpi/mpiutil.c
new file mode 100644
index 000000000..aa8c46544
--- /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 change 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 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");