572 lines
14 KiB
C
572 lines
14 KiB
C
// Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) All rights reserved.
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// SPDX-License-Identifier: Apache-2.0
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#include <openssl/bn.h>
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#include <assert.h>
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#include "internal.h"
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#if !defined(OPENSSL_NO_ASM) && defined(OPENSSL_X86)
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// See asm/bn-586.pl.
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#define BN_ADD_ASM
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#define BN_MUL_ASM
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#endif
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#if !defined(OPENSSL_NO_ASM) && defined(OPENSSL_X86_64) && \
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(defined(__GNUC__) || defined(__clang__))
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// See asm/x86_64-gcc.c
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#define BN_ADD_ASM
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#define BN_MUL_ASM
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#endif
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#if !defined(OPENSSL_NO_ASM) && defined(OPENSSL_AARCH64)
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// See asm/bn-armv8.pl.
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#define BN_ADD_ASM
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#endif
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#if !defined(BN_MUL_ASM)
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#ifdef BN_ULLONG
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#define mul_add(r, a, w, c) \
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do { \
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BN_ULLONG t; \
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t = (BN_ULLONG)(w) * (a) + (r) + (c); \
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(r) = Lw(t); \
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(c) = Hw(t); \
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} while (0)
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#define mul(r, a, w, c) \
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do { \
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BN_ULLONG t; \
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t = (BN_ULLONG)(w) * (a) + (c); \
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(r) = Lw(t); \
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(c) = Hw(t); \
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} while (0)
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#define sqr(r0, r1, a) \
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do { \
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BN_ULLONG t; \
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t = (BN_ULLONG)(a) * (a); \
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(r0) = Lw(t); \
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(r1) = Hw(t); \
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} while (0)
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#else
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#define mul_add(r, a, w, c) \
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do { \
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BN_ULONG high, low, ret, tmp = (a); \
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ret = (r); \
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BN_UMULT_LOHI(low, high, w, tmp); \
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ret += (c); \
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(c) = (ret < (c)) ? 1 : 0; \
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(c) += high; \
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ret += low; \
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(c) += (ret < low) ? 1 : 0; \
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(r) = ret; \
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} while (0)
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#define mul(r, a, w, c) \
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do { \
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BN_ULONG high, low, ret, ta = (a); \
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BN_UMULT_LOHI(low, high, w, ta); \
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ret = low + (c); \
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(c) = high; \
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(c) += (ret < low) ? 1 : 0; \
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(r) = ret; \
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} while (0)
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#define sqr(r0, r1, a) \
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do { \
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BN_ULONG tmp = (a); \
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BN_UMULT_LOHI(r0, r1, tmp, tmp); \
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} while (0)
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#endif // !BN_ULLONG
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BN_ULONG bn_mul_add_words(BN_ULONG *rp, const BN_ULONG *ap, size_t num,
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BN_ULONG w) {
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BN_ULONG c1 = 0;
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if (num == 0) {
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return c1;
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}
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while (num & ~3) {
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mul_add(rp[0], ap[0], w, c1);
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mul_add(rp[1], ap[1], w, c1);
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mul_add(rp[2], ap[2], w, c1);
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mul_add(rp[3], ap[3], w, c1);
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ap += 4;
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rp += 4;
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num -= 4;
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}
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while (num) {
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mul_add(rp[0], ap[0], w, c1);
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ap++;
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rp++;
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num--;
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}
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return c1;
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}
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BN_ULONG bn_mul_words(BN_ULONG *rp, const BN_ULONG *ap, size_t num,
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BN_ULONG w) {
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BN_ULONG c1 = 0;
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if (num == 0) {
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return c1;
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}
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while (num & ~3) {
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mul(rp[0], ap[0], w, c1);
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mul(rp[1], ap[1], w, c1);
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mul(rp[2], ap[2], w, c1);
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mul(rp[3], ap[3], w, c1);
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ap += 4;
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rp += 4;
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num -= 4;
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}
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while (num) {
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mul(rp[0], ap[0], w, c1);
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ap++;
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rp++;
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num--;
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}
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return c1;
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}
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void bn_sqr_words(BN_ULONG *r, const BN_ULONG *a, size_t n) {
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if (n == 0) {
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return;
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}
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while (n & ~3) {
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sqr(r[0], r[1], a[0]);
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sqr(r[2], r[3], a[1]);
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sqr(r[4], r[5], a[2]);
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sqr(r[6], r[7], a[3]);
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a += 4;
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r += 8;
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n -= 4;
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}
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while (n) {
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sqr(r[0], r[1], a[0]);
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a++;
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r += 2;
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n--;
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}
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}
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// mul_add_c(a,b,c0,c1,c2) -- c+=a*b for three word number c=(c2,c1,c0)
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// mul_add_c2(a,b,c0,c1,c2) -- c+=2*a*b for three word number c=(c2,c1,c0)
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// sqr_add_c(a,i,c0,c1,c2) -- c+=a[i]^2 for three word number c=(c2,c1,c0)
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// sqr_add_c2(a,i,c0,c1,c2) -- c+=2*a[i]*a[j] for three word number c=(c2,c1,c0)
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#ifdef BN_ULLONG
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// Keep in mind that additions to multiplication result can not overflow,
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// because its high half cannot be all-ones.
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#define mul_add_c(a, b, c0, c1, c2) \
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do { \
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BN_ULONG hi; \
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BN_ULLONG t = (BN_ULLONG)(a) * (b); \
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t += (c0); /* no carry */ \
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(c0) = (BN_ULONG)Lw(t); \
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hi = (BN_ULONG)Hw(t); \
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(c1) += (hi); \
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(c2) += (c1) < hi; \
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} while (0)
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#define mul_add_c2(a, b, c0, c1, c2) \
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do { \
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BN_ULONG hi; \
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BN_ULLONG t = (BN_ULLONG)(a) * (b); \
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BN_ULLONG tt = t + (c0); /* no carry */ \
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(c0) = (BN_ULONG)Lw(tt); \
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hi = (BN_ULONG)Hw(tt); \
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(c1) += hi; \
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(c2) += (c1) < hi; \
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t += (c0); /* no carry */ \
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(c0) = (BN_ULONG)Lw(t); \
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hi = (BN_ULONG)Hw(t); \
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(c1) += hi; \
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(c2) += (c1) < hi; \
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} while (0)
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#define sqr_add_c(a, i, c0, c1, c2) \
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do { \
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BN_ULONG hi; \
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BN_ULLONG t = (BN_ULLONG)(a)[i] * (a)[i]; \
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t += (c0); /* no carry */ \
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(c0) = (BN_ULONG)Lw(t); \
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hi = (BN_ULONG)Hw(t); \
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(c1) += hi; \
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(c2) += (c1) < hi; \
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} while (0)
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#define sqr_add_c2(a, i, j, c0, c1, c2) mul_add_c2((a)[i], (a)[j], c0, c1, c2)
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#else
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// Keep in mind that additions to hi can not overflow, because the high word of
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// a multiplication result cannot be all-ones.
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#define mul_add_c(a, b, c0, c1, c2) \
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do { \
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BN_ULONG ta = (a), tb = (b); \
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BN_ULONG lo, hi; \
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BN_UMULT_LOHI(lo, hi, ta, tb); \
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(c0) += lo; \
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hi += ((c0) < lo) ? 1 : 0; \
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(c1) += hi; \
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(c2) += ((c1) < hi) ? 1 : 0; \
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} while (0)
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#define mul_add_c2(a, b, c0, c1, c2) \
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do { \
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BN_ULONG ta = (a), tb = (b); \
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BN_ULONG lo, hi, tt; \
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BN_UMULT_LOHI(lo, hi, ta, tb); \
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(c0) += lo; \
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tt = hi + (((c0) < lo) ? 1 : 0); \
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(c1) += tt; \
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(c2) += ((c1) < tt) ? 1 : 0; \
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(c0) += lo; \
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hi += (c0 < lo) ? 1 : 0; \
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(c1) += hi; \
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(c2) += ((c1) < hi) ? 1 : 0; \
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} while (0)
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#define sqr_add_c(a, i, c0, c1, c2) \
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do { \
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BN_ULONG ta = (a)[i]; \
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BN_ULONG lo, hi; \
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BN_UMULT_LOHI(lo, hi, ta, ta); \
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(c0) += lo; \
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hi += (c0 < lo) ? 1 : 0; \
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(c1) += hi; \
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(c2) += ((c1) < hi) ? 1 : 0; \
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} while (0)
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#define sqr_add_c2(a, i, j, c0, c1, c2) mul_add_c2((a)[i], (a)[j], c0, c1, c2)
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#endif // !BN_ULLONG
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void bn_mul_comba8(BN_ULONG r[16], const BN_ULONG a[8], const BN_ULONG b[8]) {
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BN_ULONG c1, c2, c3;
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c1 = 0;
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c2 = 0;
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c3 = 0;
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mul_add_c(a[0], b[0], c1, c2, c3);
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r[0] = c1;
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c1 = 0;
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mul_add_c(a[0], b[1], c2, c3, c1);
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mul_add_c(a[1], b[0], c2, c3, c1);
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r[1] = c2;
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c2 = 0;
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mul_add_c(a[2], b[0], c3, c1, c2);
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mul_add_c(a[1], b[1], c3, c1, c2);
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mul_add_c(a[0], b[2], c3, c1, c2);
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r[2] = c3;
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c3 = 0;
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mul_add_c(a[0], b[3], c1, c2, c3);
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mul_add_c(a[1], b[2], c1, c2, c3);
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mul_add_c(a[2], b[1], c1, c2, c3);
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mul_add_c(a[3], b[0], c1, c2, c3);
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r[3] = c1;
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c1 = 0;
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mul_add_c(a[4], b[0], c2, c3, c1);
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mul_add_c(a[3], b[1], c2, c3, c1);
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mul_add_c(a[2], b[2], c2, c3, c1);
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mul_add_c(a[1], b[3], c2, c3, c1);
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mul_add_c(a[0], b[4], c2, c3, c1);
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r[4] = c2;
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c2 = 0;
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mul_add_c(a[0], b[5], c3, c1, c2);
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mul_add_c(a[1], b[4], c3, c1, c2);
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mul_add_c(a[2], b[3], c3, c1, c2);
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mul_add_c(a[3], b[2], c3, c1, c2);
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mul_add_c(a[4], b[1], c3, c1, c2);
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mul_add_c(a[5], b[0], c3, c1, c2);
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r[5] = c3;
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c3 = 0;
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mul_add_c(a[6], b[0], c1, c2, c3);
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mul_add_c(a[5], b[1], c1, c2, c3);
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mul_add_c(a[4], b[2], c1, c2, c3);
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mul_add_c(a[3], b[3], c1, c2, c3);
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mul_add_c(a[2], b[4], c1, c2, c3);
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mul_add_c(a[1], b[5], c1, c2, c3);
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mul_add_c(a[0], b[6], c1, c2, c3);
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r[6] = c1;
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c1 = 0;
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mul_add_c(a[0], b[7], c2, c3, c1);
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mul_add_c(a[1], b[6], c2, c3, c1);
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mul_add_c(a[2], b[5], c2, c3, c1);
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mul_add_c(a[3], b[4], c2, c3, c1);
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mul_add_c(a[4], b[3], c2, c3, c1);
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mul_add_c(a[5], b[2], c2, c3, c1);
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mul_add_c(a[6], b[1], c2, c3, c1);
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mul_add_c(a[7], b[0], c2, c3, c1);
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r[7] = c2;
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c2 = 0;
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mul_add_c(a[7], b[1], c3, c1, c2);
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mul_add_c(a[6], b[2], c3, c1, c2);
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mul_add_c(a[5], b[3], c3, c1, c2);
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mul_add_c(a[4], b[4], c3, c1, c2);
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mul_add_c(a[3], b[5], c3, c1, c2);
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mul_add_c(a[2], b[6], c3, c1, c2);
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mul_add_c(a[1], b[7], c3, c1, c2);
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r[8] = c3;
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c3 = 0;
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mul_add_c(a[2], b[7], c1, c2, c3);
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mul_add_c(a[3], b[6], c1, c2, c3);
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mul_add_c(a[4], b[5], c1, c2, c3);
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mul_add_c(a[5], b[4], c1, c2, c3);
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mul_add_c(a[6], b[3], c1, c2, c3);
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mul_add_c(a[7], b[2], c1, c2, c3);
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r[9] = c1;
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c1 = 0;
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mul_add_c(a[7], b[3], c2, c3, c1);
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mul_add_c(a[6], b[4], c2, c3, c1);
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mul_add_c(a[5], b[5], c2, c3, c1);
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mul_add_c(a[4], b[6], c2, c3, c1);
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mul_add_c(a[3], b[7], c2, c3, c1);
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r[10] = c2;
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c2 = 0;
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mul_add_c(a[4], b[7], c3, c1, c2);
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mul_add_c(a[5], b[6], c3, c1, c2);
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mul_add_c(a[6], b[5], c3, c1, c2);
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mul_add_c(a[7], b[4], c3, c1, c2);
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r[11] = c3;
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c3 = 0;
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mul_add_c(a[7], b[5], c1, c2, c3);
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mul_add_c(a[6], b[6], c1, c2, c3);
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mul_add_c(a[5], b[7], c1, c2, c3);
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r[12] = c1;
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c1 = 0;
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mul_add_c(a[6], b[7], c2, c3, c1);
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mul_add_c(a[7], b[6], c2, c3, c1);
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r[13] = c2;
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c2 = 0;
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mul_add_c(a[7], b[7], c3, c1, c2);
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r[14] = c3;
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r[15] = c1;
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}
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void bn_mul_comba4(BN_ULONG r[8], const BN_ULONG a[4], const BN_ULONG b[4]) {
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BN_ULONG c1, c2, c3;
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c1 = 0;
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c2 = 0;
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c3 = 0;
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mul_add_c(a[0], b[0], c1, c2, c3);
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r[0] = c1;
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c1 = 0;
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mul_add_c(a[0], b[1], c2, c3, c1);
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mul_add_c(a[1], b[0], c2, c3, c1);
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r[1] = c2;
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c2 = 0;
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mul_add_c(a[2], b[0], c3, c1, c2);
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mul_add_c(a[1], b[1], c3, c1, c2);
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mul_add_c(a[0], b[2], c3, c1, c2);
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r[2] = c3;
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c3 = 0;
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mul_add_c(a[0], b[3], c1, c2, c3);
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mul_add_c(a[1], b[2], c1, c2, c3);
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mul_add_c(a[2], b[1], c1, c2, c3);
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mul_add_c(a[3], b[0], c1, c2, c3);
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r[3] = c1;
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c1 = 0;
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mul_add_c(a[3], b[1], c2, c3, c1);
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mul_add_c(a[2], b[2], c2, c3, c1);
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mul_add_c(a[1], b[3], c2, c3, c1);
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r[4] = c2;
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c2 = 0;
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mul_add_c(a[2], b[3], c3, c1, c2);
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mul_add_c(a[3], b[2], c3, c1, c2);
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r[5] = c3;
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c3 = 0;
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mul_add_c(a[3], b[3], c1, c2, c3);
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r[6] = c1;
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r[7] = c2;
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}
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void bn_sqr_comba8(BN_ULONG r[16], const BN_ULONG a[8]) {
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BN_ULONG c1, c2, c3;
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c1 = 0;
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c2 = 0;
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c3 = 0;
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sqr_add_c(a, 0, c1, c2, c3);
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r[0] = c1;
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c1 = 0;
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sqr_add_c2(a, 1, 0, c2, c3, c1);
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r[1] = c2;
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c2 = 0;
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sqr_add_c(a, 1, c3, c1, c2);
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sqr_add_c2(a, 2, 0, c3, c1, c2);
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r[2] = c3;
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c3 = 0;
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sqr_add_c2(a, 3, 0, c1, c2, c3);
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sqr_add_c2(a, 2, 1, c1, c2, c3);
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r[3] = c1;
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c1 = 0;
|
|
sqr_add_c(a, 2, c2, c3, c1);
|
|
sqr_add_c2(a, 3, 1, c2, c3, c1);
|
|
sqr_add_c2(a, 4, 0, c2, c3, c1);
|
|
r[4] = c2;
|
|
c2 = 0;
|
|
sqr_add_c2(a, 5, 0, c3, c1, c2);
|
|
sqr_add_c2(a, 4, 1, c3, c1, c2);
|
|
sqr_add_c2(a, 3, 2, c3, c1, c2);
|
|
r[5] = c3;
|
|
c3 = 0;
|
|
sqr_add_c(a, 3, c1, c2, c3);
|
|
sqr_add_c2(a, 4, 2, c1, c2, c3);
|
|
sqr_add_c2(a, 5, 1, c1, c2, c3);
|
|
sqr_add_c2(a, 6, 0, c1, c2, c3);
|
|
r[6] = c1;
|
|
c1 = 0;
|
|
sqr_add_c2(a, 7, 0, c2, c3, c1);
|
|
sqr_add_c2(a, 6, 1, c2, c3, c1);
|
|
sqr_add_c2(a, 5, 2, c2, c3, c1);
|
|
sqr_add_c2(a, 4, 3, c2, c3, c1);
|
|
r[7] = c2;
|
|
c2 = 0;
|
|
sqr_add_c(a, 4, c3, c1, c2);
|
|
sqr_add_c2(a, 5, 3, c3, c1, c2);
|
|
sqr_add_c2(a, 6, 2, c3, c1, c2);
|
|
sqr_add_c2(a, 7, 1, c3, c1, c2);
|
|
r[8] = c3;
|
|
c3 = 0;
|
|
sqr_add_c2(a, 7, 2, c1, c2, c3);
|
|
sqr_add_c2(a, 6, 3, c1, c2, c3);
|
|
sqr_add_c2(a, 5, 4, c1, c2, c3);
|
|
r[9] = c1;
|
|
c1 = 0;
|
|
sqr_add_c(a, 5, c2, c3, c1);
|
|
sqr_add_c2(a, 6, 4, c2, c3, c1);
|
|
sqr_add_c2(a, 7, 3, c2, c3, c1);
|
|
r[10] = c2;
|
|
c2 = 0;
|
|
sqr_add_c2(a, 7, 4, c3, c1, c2);
|
|
sqr_add_c2(a, 6, 5, c3, c1, c2);
|
|
r[11] = c3;
|
|
c3 = 0;
|
|
sqr_add_c(a, 6, c1, c2, c3);
|
|
sqr_add_c2(a, 7, 5, c1, c2, c3);
|
|
r[12] = c1;
|
|
c1 = 0;
|
|
sqr_add_c2(a, 7, 6, c2, c3, c1);
|
|
r[13] = c2;
|
|
c2 = 0;
|
|
sqr_add_c(a, 7, c3, c1, c2);
|
|
r[14] = c3;
|
|
r[15] = c1;
|
|
}
|
|
|
|
void bn_sqr_comba4(BN_ULONG r[8], const BN_ULONG a[4]) {
|
|
BN_ULONG c1, c2, c3;
|
|
|
|
c1 = 0;
|
|
c2 = 0;
|
|
c3 = 0;
|
|
sqr_add_c(a, 0, c1, c2, c3);
|
|
r[0] = c1;
|
|
c1 = 0;
|
|
sqr_add_c2(a, 1, 0, c2, c3, c1);
|
|
r[1] = c2;
|
|
c2 = 0;
|
|
sqr_add_c(a, 1, c3, c1, c2);
|
|
sqr_add_c2(a, 2, 0, c3, c1, c2);
|
|
r[2] = c3;
|
|
c3 = 0;
|
|
sqr_add_c2(a, 3, 0, c1, c2, c3);
|
|
sqr_add_c2(a, 2, 1, c1, c2, c3);
|
|
r[3] = c1;
|
|
c1 = 0;
|
|
sqr_add_c(a, 2, c2, c3, c1);
|
|
sqr_add_c2(a, 3, 1, c2, c3, c1);
|
|
r[4] = c2;
|
|
c2 = 0;
|
|
sqr_add_c2(a, 3, 2, c3, c1, c2);
|
|
r[5] = c3;
|
|
c3 = 0;
|
|
sqr_add_c(a, 3, c1, c2, c3);
|
|
r[6] = c1;
|
|
r[7] = c2;
|
|
}
|
|
|
|
#undef mul_add
|
|
#undef mul
|
|
#undef sqr
|
|
#undef mul_add_c
|
|
#undef mul_add_c2
|
|
#undef sqr_add_c
|
|
#undef sqr_add_c2
|
|
|
|
#endif // !BN_MUL_ASM
|
|
|
|
#if !defined(BN_ADD_ASM)
|
|
|
|
BN_ULONG bn_add_words(BN_ULONG *r, const BN_ULONG *a, const BN_ULONG *b,
|
|
size_t n) {
|
|
if (n == 0) {
|
|
return 0;
|
|
}
|
|
|
|
BN_ULONG carry = 0;
|
|
while (n & ~3) {
|
|
r[0] = CRYPTO_addc_w(a[0], b[0], carry, &carry);
|
|
r[1] = CRYPTO_addc_w(a[1], b[1], carry, &carry);
|
|
r[2] = CRYPTO_addc_w(a[2], b[2], carry, &carry);
|
|
r[3] = CRYPTO_addc_w(a[3], b[3], carry, &carry);
|
|
a += 4;
|
|
b += 4;
|
|
r += 4;
|
|
n -= 4;
|
|
}
|
|
while (n) {
|
|
r[0] = CRYPTO_addc_w(a[0], b[0], carry, &carry);
|
|
a++;
|
|
b++;
|
|
r++;
|
|
n--;
|
|
}
|
|
return carry;
|
|
}
|
|
|
|
BN_ULONG bn_sub_words(BN_ULONG *r, const BN_ULONG *a, const BN_ULONG *b,
|
|
size_t n) {
|
|
if (n == 0) {
|
|
return (BN_ULONG)0;
|
|
}
|
|
|
|
BN_ULONG borrow = 0;
|
|
while (n & ~3) {
|
|
r[0] = CRYPTO_subc_w(a[0], b[0], borrow, &borrow);
|
|
r[1] = CRYPTO_subc_w(a[1], b[1], borrow, &borrow);
|
|
r[2] = CRYPTO_subc_w(a[2], b[2], borrow, &borrow);
|
|
r[3] = CRYPTO_subc_w(a[3], b[3], borrow, &borrow);
|
|
a += 4;
|
|
b += 4;
|
|
r += 4;
|
|
n -= 4;
|
|
}
|
|
while (n) {
|
|
r[0] = CRYPTO_subc_w(a[0], b[0], borrow, &borrow);
|
|
a++;
|
|
b++;
|
|
r++;
|
|
n--;
|
|
}
|
|
return borrow;
|
|
}
|
|
|
|
#endif // !BN_ADD_ASM
|