linux-master/crypto/ecc.c

233 /* Computes result = in << c, returning carry. Can modify in place
239 	u64 carry = 0;
245 		result[i] = (temp << shift) | carry;
246 		carry = temp >> (64 - shift);
249 	return carry;
256 	u64 carry = 0;
262 		*vli = (temp >> 1) | carry;
263 		carry = temp << 63;
267 /* Computes result = left + right, returning carry. Can modify in place. */
271 	u64 carry = 0;
277 		sum = left[i] + right[i] + carry;
279 			carry = (sum < left[i]);
284 	return carry;
287 /* Computes result = left + right, returning carry. Can modify in place. */
291 	u64 carry = right;
297 		sum = left[i] + carry;
299 			carry = (sum < left[i]);
301 			carry = !!carry;
306 	return carry;
439 		/* no carry */
494 	u64 carry;
496 	carry = vli_add(result, left, right, ndigits);
501 	if (carry || vli_cmp(result, mod, ndigits) >= 0)
571 	int carry; /* last bit that doesn't fit into q */
578 	/* q and carry are top bits */
581 	carry = vli_is_negative(r, ndigits);
582 	if (carry)
584 	for (i = 1; carry || !vli_is_zero(q, ndigits); i++) {
588 		if (carry)
592 		carry = vli_is_negative(qc, ndigits);
593 		if (carry)
619 	u64 carry = 0;
629 			mod_m[word_shift + i] = (mod[i] << bit_shift) | carry;
630 			carry = mod[i] >> (64 - bit_shift);
677 		u64 carry;
679 		carry = vli_sub(r, r, mod, ndigits);
680 		vli_usub(r + ndigits, r + ndigits, carry, ndigits);
693 	int carry;
698 	carry = vli_add(result, result, tmp, ndigits);
703 	carry += vli_add(result, result, tmp, ndigits);
707 	carry += vli_add(result, result, tmp, ndigits);
709 	while (carry || vli_cmp(curve_prime, result, ndigits) != 1)
710 		carry -= vli_sub(result, result, curve_prime, ndigits);
719 	int carry;
730 	carry = vli_lshift(tmp, tmp, 1, ndigits);
731 	carry += vli_add(result, result, tmp, ndigits);
737 	carry += vli_lshift(tmp, tmp, 1, ndigits);
738 	carry += vli_add(result, result, tmp, ndigits);
745 	carry += vli_add(result, result, tmp, ndigits);
752 	carry += vli_add(result, result, tmp, ndigits);
759 	carry -= vli_sub(result, result, tmp, ndigits);
766 	carry -= vli_sub(result, result, tmp, ndigits);
773 	carry -= vli_sub(result, result, tmp, ndigits);
780 	carry -= vli_sub(result, result, tmp, ndigits);
782 	if (carry < 0) {
784 			carry += vli_add(result, result, curve_prime, ndigits);
785 		} while (carry < 0);
787 		while (carry || vli_cmp(curve_prime, result, ndigits) != 1)
788 			carry -= vli_sub(result, result, curve_prime, ndigits);
802 	int carry;
815 	carry = vli_lshift(tmp, tmp, 1, ndigits);
816 	carry += vli_add(result, result, tmp, ndigits);
825 	carry += vli_add(result, result, tmp, ndigits);
834 	carry += vli_add(result, result, tmp, ndigits);
843 	carry += vli_add(result, result, tmp, ndigits);
852 	carry += vli_add(result, result, tmp, ndigits);
861 	carry += vli_add(result, result, tmp, ndigits);
870 	carry -= vli_sub(result, result, tmp, ndigits);
879 	carry -= vli_sub(result, result, tmp, ndigits);
888 	carry -= vli_sub(result, result, tmp, ndigits);
890 	if (carry < 0) {
892 			carry += vli_add(result, result, curve_prime, ndigits);
893 		} while (carry < 0);
895 		while (carry || vli_cmp(curve_prime, result, ndigits) != 1)
896 			carry -= vli_sub(result, result, curve_prime, ndigits);
995 	u64 carry;
1010 		carry = 0;
1016 				carry = vli_add(u, u, mod, ndigits);
1019 			if (carry)
1025 				carry = vli_add(v, v, mod, ndigits);
1028 			if (carry)
1039 				carry = vli_add(u, u, mod, ndigits);
1042 			if (carry)
1053 				carry = vli_add(v, v, mod, ndigits);
1056 			if (carry)
1117 		u64 carry = vli_add(x1, x1, curve_prime, ndigits);
1120 		x1[ndigits - 1] |= carry << 63;
1293 	int carry;
1295 	carry = vli_add(sk[0], scalar, curve->n, ndigits);
1297 	scalar = sk[!carry];