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diff --git a/include/crypto/internal/ecc.h b/include/crypto/internal/ecc.h
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+/*
+ * Copyright (c) 2013, Kenneth MacKay
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+#ifndef _CRYPTO_ECC_H
+#define _CRYPTO_ECC_H
+
+#include <crypto/ecc_curve.h>
+#include <asm/unaligned.h>
+
+/* One digit is u64 qword. */
+#define ECC_CURVE_NIST_P192_DIGITS 3
+#define ECC_CURVE_NIST_P256_DIGITS 4
+#define ECC_CURVE_NIST_P384_DIGITS 6
+#define ECC_MAX_DIGITS (512 / 64) /* due to ecrdsa */
+
+#define ECC_DIGITS_TO_BYTES_SHIFT 3
+
+#define ECC_MAX_BYTES (ECC_MAX_DIGITS << ECC_DIGITS_TO_BYTES_SHIFT)
+
+#define ECC_POINT_INIT(x, y, ndigits) (struct ecc_point) { x, y, ndigits }
+
+/**
+ * ecc_swap_digits() - Copy ndigits from big endian array to native array
+ * @in: Input array
+ * @out: Output array
+ * @ndigits: Number of digits to copy
+ */
+static inline void ecc_swap_digits(const void *in, u64 *out, unsigned int ndigits)
+{
+ const __be64 *src = (__force __be64 *)in;
+ int i;
+
+ for (i = 0; i < ndigits; i++)
+ out[i] = get_unaligned_be64(&src[ndigits - 1 - i]);
+}
+
+/**
+ * ecc_is_key_valid() - Validate a given ECDH private key
+ *
+ * @curve_id: id representing the curve to use
+ * @ndigits: curve's number of digits
+ * @private_key: private key to be used for the given curve
+ * @private_key_len: private key length
+ *
+ * Returns 0 if the key is acceptable, a negative value otherwise
+ */
+int ecc_is_key_valid(unsigned int curve_id, unsigned int ndigits,
+ const u64 *private_key, unsigned int private_key_len);
+
+/**
+ * ecc_gen_privkey() - Generates an ECC private key.
+ * The private key is a random integer in the range 0 < random < n, where n is a
+ * prime that is the order of the cyclic subgroup generated by the distinguished
+ * point G.
+ * @curve_id: id representing the curve to use
+ * @ndigits: curve number of digits
+ * @private_key: buffer for storing the generated private key
+ *
+ * Returns 0 if the private key was generated successfully, a negative value
+ * if an error occurred.
+ */
+int ecc_gen_privkey(unsigned int curve_id, unsigned int ndigits, u64 *privkey);
+
+/**
+ * ecc_make_pub_key() - Compute an ECC public key
+ *
+ * @curve_id: id representing the curve to use
+ * @ndigits: curve's number of digits
+ * @private_key: pregenerated private key for the given curve
+ * @public_key: buffer for storing the generated public key
+ *
+ * Returns 0 if the public key was generated successfully, a negative value
+ * if an error occurred.
+ */
+int ecc_make_pub_key(const unsigned int curve_id, unsigned int ndigits,
+ const u64 *private_key, u64 *public_key);
+
+/**
+ * crypto_ecdh_shared_secret() - Compute a shared secret
+ *
+ * @curve_id: id representing the curve to use
+ * @ndigits: curve's number of digits
+ * @private_key: private key of part A
+ * @public_key: public key of counterpart B
+ * @secret: buffer for storing the calculated shared secret
+ *
+ * Note: It is recommended that you hash the result of crypto_ecdh_shared_secret
+ * before using it for symmetric encryption or HMAC.
+ *
+ * Returns 0 if the shared secret was generated successfully, a negative value
+ * if an error occurred.
+ */
+int crypto_ecdh_shared_secret(unsigned int curve_id, unsigned int ndigits,
+ const u64 *private_key, const u64 *public_key,
+ u64 *secret);
+
+/**
+ * ecc_is_pubkey_valid_partial() - Partial public key validation
+ *
+ * @curve: elliptic curve domain parameters
+ * @pk: public key as a point
+ *
+ * Valdiate public key according to SP800-56A section 5.6.2.3.4 ECC Partial
+ * Public-Key Validation Routine.
+ *
+ * Note: There is no check that the public key is in the correct elliptic curve
+ * subgroup.
+ *
+ * Return: 0 if validation is successful, -EINVAL if validation is failed.
+ */
+int ecc_is_pubkey_valid_partial(const struct ecc_curve *curve,
+ struct ecc_point *pk);
+
+/**
+ * ecc_is_pubkey_valid_full() - Full public key validation
+ *
+ * @curve: elliptic curve domain parameters
+ * @pk: public key as a point
+ *
+ * Valdiate public key according to SP800-56A section 5.6.2.3.3 ECC Full
+ * Public-Key Validation Routine.
+ *
+ * Return: 0 if validation is successful, -EINVAL if validation is failed.
+ */
+int ecc_is_pubkey_valid_full(const struct ecc_curve *curve,
+ struct ecc_point *pk);
+
+/**
+ * vli_is_zero() - Determine is vli is zero
+ *
+ * @vli: vli to check.
+ * @ndigits: length of the @vli
+ */
+bool vli_is_zero(const u64 *vli, unsigned int ndigits);
+
+/**
+ * vli_cmp() - compare left and right vlis
+ *
+ * @left: vli
+ * @right: vli
+ * @ndigits: length of both vlis
+ *
+ * Returns sign of @left - @right, i.e. -1 if @left < @right,
+ * 0 if @left == @right, 1 if @left > @right.
+ */
+int vli_cmp(const u64 *left, const u64 *right, unsigned int ndigits);
+
+/**
+ * vli_sub() - Subtracts right from left
+ *
+ * @result: where to write result
+ * @left: vli
+ * @right vli
+ * @ndigits: length of all vlis
+ *
+ * Note: can modify in-place.
+ *
+ * Return: carry bit.
+ */
+u64 vli_sub(u64 *result, const u64 *left, const u64 *right,
+ unsigned int ndigits);
+
+/**
+ * vli_from_be64() - Load vli from big-endian u64 array
+ *
+ * @dest: destination vli
+ * @src: source array of u64 BE values
+ * @ndigits: length of both vli and array
+ */
+void vli_from_be64(u64 *dest, const void *src, unsigned int ndigits);
+
+/**
+ * vli_from_le64() - Load vli from little-endian u64 array
+ *
+ * @dest: destination vli
+ * @src: source array of u64 LE values
+ * @ndigits: length of both vli and array
+ */
+void vli_from_le64(u64 *dest, const void *src, unsigned int ndigits);
+
+/**
+ * vli_mod_inv() - Modular inversion
+ *
+ * @result: where to write vli number
+ * @input: vli value to operate on
+ * @mod: modulus
+ * @ndigits: length of all vlis
+ */
+void vli_mod_inv(u64 *result, const u64 *input, const u64 *mod,
+ unsigned int ndigits);
+
+/**
+ * vli_mod_mult_slow() - Modular multiplication
+ *
+ * @result: where to write result value
+ * @left: vli number to multiply with @right
+ * @right: vli number to multiply with @left
+ * @mod: modulus
+ * @ndigits: length of all vlis
+ *
+ * Note: Assumes that mod is big enough curve order.
+ */
+void vli_mod_mult_slow(u64 *result, const u64 *left, const u64 *right,
+ const u64 *mod, unsigned int ndigits);
+
+/**
+ * vli_num_bits() - Counts the number of bits required for vli.
+ *
+ * @vli: vli to check.
+ * @ndigits: Length of the @vli
+ *
+ * Return: The number of bits required to represent @vli.
+ */
+unsigned int vli_num_bits(const u64 *vli, unsigned int ndigits);
+
+/**
+ * ecc_aloc_point() - Allocate ECC point.
+ *
+ * @ndigits: Length of vlis in u64 qwords.
+ *
+ * Return: Pointer to the allocated point or NULL if allocation failed.
+ */
+struct ecc_point *ecc_alloc_point(unsigned int ndigits);
+
+/**
+ * ecc_free_point() - Free ECC point.
+ *
+ * @p: The point to free.
+ */
+void ecc_free_point(struct ecc_point *p);
+
+/**
+ * ecc_point_is_zero() - Check if point is zero.
+ *
+ * @p: Point to check for zero.
+ *
+ * Return: true if point is the point at infinity, false otherwise.
+ */
+bool ecc_point_is_zero(const struct ecc_point *point);
+
+/**
+ * ecc_point_mult_shamir() - Add two points multiplied by scalars
+ *
+ * @result: resulting point
+ * @x: scalar to multiply with @p
+ * @p: point to multiply with @x
+ * @y: scalar to multiply with @q
+ * @q: point to multiply with @y
+ * @curve: curve
+ *
+ * Returns result = x * p + x * q over the curve.
+ * This works faster than two multiplications and addition.
+ */
+void ecc_point_mult_shamir(const struct ecc_point *result,
+ const u64 *x, const struct ecc_point *p,
+ const u64 *y, const struct ecc_point *q,
+ const struct ecc_curve *curve);
+
+#endif