intermediate changes

ref:cde9a383711a11544ce7e107a78147fb96cc4029

1 files changed, 235 insertions, 0 deletions

diff --git a/contrib/libs/openssl/crypto/ec/curve448/scalar.c b/contrib/libs/openssl/crypto/ec/curve448/scalar.c
new file mode 100644
index 0000000000..347794bbac
--- /dev/null
+++ b/contrib/libs/openssl/crypto/ec/curve448/scalar.c
@@ -0,0 +1,235 @@
+/*
+ * Copyright 2017-2019 The OpenSSL Project Authors. All Rights Reserved.
+ * Copyright 2015-2016 Cryptography Research, Inc.
+ *
+ * Licensed under the OpenSSL license (the "License").  You may not use
+ * this file except in compliance with the License.  You can obtain a copy
+ * in the file LICENSE in the source distribution or at
+ * https://www.openssl.org/source/license.html
+ *
+ * Originally written by Mike Hamburg
+ */
+#include <openssl/crypto.h>
+
+#include "word.h"
+#include "point_448.h"
+
+static const c448_word_t MONTGOMERY_FACTOR = (c448_word_t) 0x3bd440fae918bc5ULL;
+static const curve448_scalar_t sc_p = {
+    {
+        {
+            SC_LIMB(0x2378c292ab5844f3ULL), SC_LIMB(0x216cc2728dc58f55ULL),
+            SC_LIMB(0xc44edb49aed63690ULL), SC_LIMB(0xffffffff7cca23e9ULL),
+            SC_LIMB(0xffffffffffffffffULL), SC_LIMB(0xffffffffffffffffULL),
+            SC_LIMB(0x3fffffffffffffffULL)
+        }
+    }
+}, sc_r2 = {
+    {
+        {
+
+            SC_LIMB(0xe3539257049b9b60ULL), SC_LIMB(0x7af32c4bc1b195d9ULL),
+            SC_LIMB(0x0d66de2388ea1859ULL), SC_LIMB(0xae17cf725ee4d838ULL),
+            SC_LIMB(0x1a9cc14ba3c47c44ULL), SC_LIMB(0x2052bcb7e4d070afULL),
+            SC_LIMB(0x3402a939f823b729ULL)
+        }
+    }
+};
+
+#define WBITS C448_WORD_BITS   /* NB this may be different from ARCH_WORD_BITS */
+
+const curve448_scalar_t curve448_scalar_one = {{{1}}};
+const curve448_scalar_t curve448_scalar_zero = {{{0}}};
+
+/*
+ * {extra,accum} - sub +? p
+ * Must have extra <= 1
+ */
+static void sc_subx(curve448_scalar_t out,
+                    const c448_word_t accum[C448_SCALAR_LIMBS],
+                    const curve448_scalar_t sub,
+                    const curve448_scalar_t p, c448_word_t extra)
+{
+    c448_dsword_t chain = 0;
+    unsigned int i;
+    c448_word_t borrow;
+
+    for (i = 0; i < C448_SCALAR_LIMBS; i++) {
+        chain = (chain + accum[i]) - sub->limb[i];
+        out->limb[i] = (c448_word_t)chain;
+        chain >>= WBITS;
+    }
+    borrow = (c448_word_t)chain + extra;     /* = 0 or -1 */
+
+    chain = 0;
+    for (i = 0; i < C448_SCALAR_LIMBS; i++) {
+        chain = (chain + out->limb[i]) + (p->limb[i] & borrow);
+        out->limb[i] = (c448_word_t)chain;
+        chain >>= WBITS;
+    }
+}
+
+static void sc_montmul(curve448_scalar_t out, const curve448_scalar_t a,
+                       const curve448_scalar_t b)
+{
+    unsigned int i, j;
+    c448_word_t accum[C448_SCALAR_LIMBS + 1] = { 0 };
+    c448_word_t hi_carry = 0;
+
+    for (i = 0; i < C448_SCALAR_LIMBS; i++) {
+        c448_word_t mand = a->limb[i];
+        const c448_word_t *mier = b->limb;
+
+        c448_dword_t chain = 0;
+        for (j = 0; j < C448_SCALAR_LIMBS; j++) {
+            chain += ((c448_dword_t) mand) * mier[j] + accum[j];
+            accum[j] = (c448_word_t)chain;
+            chain >>= WBITS;
+        }
+        accum[j] = (c448_word_t)chain;
+
+        mand = accum[0] * MONTGOMERY_FACTOR;
+        chain = 0;
+        mier = sc_p->limb;
+        for (j = 0; j < C448_SCALAR_LIMBS; j++) {
+            chain += (c448_dword_t) mand *mier[j] + accum[j];
+            if (j)
+                accum[j - 1] = (c448_word_t)chain;
+            chain >>= WBITS;
+        }
+        chain += accum[j];
+        chain += hi_carry;
+        accum[j - 1] = (c448_word_t)chain;
+        hi_carry = chain >> WBITS;
+    }
+
+    sc_subx(out, accum, sc_p, sc_p, hi_carry);
+}
+
+void curve448_scalar_mul(curve448_scalar_t out, const curve448_scalar_t a,
+                         const curve448_scalar_t b)
+{
+    sc_montmul(out, a, b);
+    sc_montmul(out, out, sc_r2);
+}
+
+void curve448_scalar_sub(curve448_scalar_t out, const curve448_scalar_t a,
+                         const curve448_scalar_t b)
+{
+    sc_subx(out, a->limb, b, sc_p, 0);
+}
+
+void curve448_scalar_add(curve448_scalar_t out, const curve448_scalar_t a,
+                         const curve448_scalar_t b)
+{
+    c448_dword_t chain = 0;
+    unsigned int i;
+
+    for (i = 0; i < C448_SCALAR_LIMBS; i++) {
+        chain = (chain + a->limb[i]) + b->limb[i];
+        out->limb[i] = (c448_word_t)chain;
+        chain >>= WBITS;
+    }
+    sc_subx(out, out->limb, sc_p, sc_p, (c448_word_t)chain);
+}
+
+static ossl_inline void scalar_decode_short(curve448_scalar_t s,
+                                            const unsigned char *ser,
+                                            size_t nbytes)
+{
+    size_t i, j, k = 0;
+
+    for (i = 0; i < C448_SCALAR_LIMBS; i++) {
+        c448_word_t out = 0;
+
+        for (j = 0; j < sizeof(c448_word_t) && k < nbytes; j++, k++)
+            out |= ((c448_word_t) ser[k]) << (8 * j);
+        s->limb[i] = out;
+    }
+}
+
+c448_error_t curve448_scalar_decode(
+                                curve448_scalar_t s,
+                                const unsigned char ser[C448_SCALAR_BYTES])
+{
+    unsigned int i;
+    c448_dsword_t accum = 0;
+
+    scalar_decode_short(s, ser, C448_SCALAR_BYTES);
+    for (i = 0; i < C448_SCALAR_LIMBS; i++)
+        accum = (accum + s->limb[i] - sc_p->limb[i]) >> WBITS;
+    /* Here accum == 0 or -1 */
+
+    curve448_scalar_mul(s, s, curve448_scalar_one); /* ham-handed reduce */
+
+    return c448_succeed_if(~word_is_zero((uint32_t)accum));
+}
+
+void curve448_scalar_destroy(curve448_scalar_t scalar)
+{
+    OPENSSL_cleanse(scalar, sizeof(curve448_scalar_t));
+}
+
+void curve448_scalar_decode_long(curve448_scalar_t s,
+                                 const unsigned char *ser, size_t ser_len)
+{
+    size_t i;
+    curve448_scalar_t t1, t2;
+
+    if (ser_len == 0) {
+        curve448_scalar_copy(s, curve448_scalar_zero);
+        return;
+    }
+
+    i = ser_len - (ser_len % C448_SCALAR_BYTES);
+    if (i == ser_len)
+        i -= C448_SCALAR_BYTES;
+
+    scalar_decode_short(t1, &ser[i], ser_len - i);
+
+    if (ser_len == sizeof(curve448_scalar_t)) {
+        assert(i == 0);
+        /* ham-handed reduce */
+        curve448_scalar_mul(s, t1, curve448_scalar_one);
+        curve448_scalar_destroy(t1);
+        return;
+    }
+
+    while (i) {
+        i -= C448_SCALAR_BYTES;
+        sc_montmul(t1, t1, sc_r2);
+        (void)curve448_scalar_decode(t2, ser + i);
+        curve448_scalar_add(t1, t1, t2);
+    }
+
+    curve448_scalar_copy(s, t1);
+    curve448_scalar_destroy(t1);
+    curve448_scalar_destroy(t2);
+}
+
+void curve448_scalar_encode(unsigned char ser[C448_SCALAR_BYTES],
+                            const curve448_scalar_t s)
+{
+    unsigned int i, j, k = 0;
+
+    for (i = 0; i < C448_SCALAR_LIMBS; i++) {
+        for (j = 0; j < sizeof(c448_word_t); j++, k++)
+            ser[k] = s->limb[i] >> (8 * j);
+    }
+}
+
+void curve448_scalar_halve(curve448_scalar_t out, const curve448_scalar_t a)
+{
+    c448_word_t mask = 0 - (a->limb[0] & 1);
+    c448_dword_t chain = 0;
+    unsigned int i;
+
+    for (i = 0; i < C448_SCALAR_LIMBS; i++) {
+        chain = (chain + a->limb[i]) + (sc_p->limb[i] & mask);
+        out->limb[i] = (c448_word_t)chain;
+        chain >>= C448_WORD_BITS;
+    }
+    for (i = 0; i < C448_SCALAR_LIMBS - 1; i++)
+        out->limb[i] = out->limb[i] >> 1 | out->limb[i + 1] << (WBITS - 1);
+    out->limb[i] = out->limb[i] >> 1 | (c448_word_t)(chain << (WBITS - 1));
+}