/*
- * Copyright 2017 The OpenSSL Project Authors. All Rights Reserved.
+ * Copyright 2017-2018 The OpenSSL Project Authors. All Rights Reserved.
* Copyright 2015-2016 Cryptography Research, Inc.
*
- * Licensed under the OpenSSL license (the "License"). You may not use
+ * Licensed under the Apache License 2.0 (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
*/
-#ifndef __C448_POINT_448_H__
-# define __C448_POINT_448_H__ 1
+#ifndef HEADER_POINT_448_H
+# define HEADER_POINT_448_H
# include "curve448utils.h"
# include "field.h"
-#ifdef __cplusplus
-extern "C" {
-#endif
+/* Comb config: number of combs, n, t, s. */
+#define COMBS_N 5
+#define COMBS_T 5
+#define COMBS_S 18
-# define C448_448_SCALAR_LIMBS ((446-1)/C448_WORD_BITS+1)
+/* Projective Niels coordinates */
+typedef struct {
+ gf a, b, c;
+} niels_s, niels_t[1];
+typedef struct {
+ niels_t n;
+ gf z;
+} pniels_t[1];
+
+/* Precomputed base */
+struct curve448_precomputed_s {
+ niels_t table[COMBS_N << (COMBS_T - 1)];
+};
+
+# define C448_SCALAR_LIMBS ((446-1)/C448_WORD_BITS+1)
/* The number of bits in a scalar */
-# define C448_448_SCALAR_BITS 446
+# define C448_SCALAR_BITS 446
/* Number of bytes in a serialized scalar. */
-# define C448_448_SCALAR_BYTES 56
+# define C448_SCALAR_BYTES 56
/* X448 encoding ratio. */
-# define C448_X448_ENCODE_RATIO 2
+# define X448_ENCODE_RATIO 2
/* Number of bytes in an x448 public key */
-# define C448_X448_PUBLIC_BYTES 56
+# define X448_PUBLIC_BYTES 56
/* Number of bytes in an x448 private key */
-# define C448_X448_PRIVATE_BYTES 56
+# define X448_PRIVATE_BYTES 56
/* Twisted Edwards extended homogeneous coordinates */
typedef struct curve448_point_s {
/* Scalar is stored packed, because we don't need the speed. */
typedef struct curve448_scalar_s {
- c448_word_t limb[C448_448_SCALAR_LIMBS];
+ c448_word_t limb[C448_SCALAR_LIMBS];
} curve448_scalar_t[1];
/* A scalar equal to 1. */
/* Precomputed table for the base point on the curve. */
extern const struct curve448_precomputed_s *curve448_precomputed_base;
+extern const niels_t *curve448_wnaf_base;
/*
* Read a scalar from wire format or from bytes.
* C448_FAILURE: The scalar was greater than the modulus, and has been reduced
* modulo that modulus.
*/
-__owur c448_error_t curve448_scalar_decode(
- curve448_scalar_t out,
- const unsigned char ser[C448_448_SCALAR_BYTES]);
+c448_error_t curve448_scalar_decode(curve448_scalar_t out,
+ const unsigned char ser[C448_SCALAR_BYTES]);
/*
* Read a scalar from wire format or from bytes. Reduces mod scalar prime.
* ser (out): Serialized form of a scalar.
* s (in): Deserialized scalar.
*/
-void curve448_scalar_encode(unsigned char ser[C448_448_SCALAR_BYTES],
+void curve448_scalar_encode(unsigned char ser[C448_SCALAR_BYTES],
const curve448_scalar_t s);
/*
- * Add two scalars. The scalars may use the same memory.
- *
+ * Add two scalars. |a|, |b| and |out| may alias each other.
+ *
* a (in): One scalar.
* b (in): Another scalar.
* out (out): a+b.
const curve448_scalar_t a, const curve448_scalar_t b);
/*
- * Subtract two scalars. The scalars may use the same memory.
+ * Subtract two scalars. |a|, |b| and |out| may alias each other.
* a (in): One scalar.
* b (in): Another scalar.
* out (out): a-b.
const curve448_scalar_t a, const curve448_scalar_t b);
/*
- * Multiply two scalars. The scalars may use the same memory.
- *
+ * Multiply two scalars. |a|, |b| and |out| may alias each other.
+ *
* a (in): One scalar.
* b (in): Another scalar.
* out (out): a*b.
const curve448_scalar_t a, const curve448_scalar_t b);
/*
-* Halve a scalar. The scalars may use the same memory.
-*
+* Halve a scalar. |a| and |out| may alias each other.
+*
* a (in): A scalar.
* out (out): a/2.
*/
void curve448_scalar_halve(curve448_scalar_t out, const curve448_scalar_t a);
/*
- * Copy a scalar. The scalars may use the same memory, in which case this
+ * Copy a scalar. The scalars may alias each other, in which case this
* function does nothing.
- *
+ *
* a (in): A scalar.
* out (out): Will become a copy of a.
*/
*
* a (in): A point.
* b (in): Another point.
- *
+ *
* Returns:
* C448_TRUE: The points are equal.
* C448_FALSE: The points are not equal.
* C448_FAILURE: The scalarmul didn't succeed, because the base point is in a
* small subgroup.
*/
-__owur c448_error_t c448_x448(uint8_t out[C448_X448_PUBLIC_BYTES],
- const uint8_t base[C448_X448_PUBLIC_BYTES],
- const uint8_t scalar[C448_X448_PRIVATE_BYTES]);
+__owur c448_error_t x448_int(uint8_t out[X448_PUBLIC_BYTES],
+ const uint8_t base[X448_PUBLIC_BYTES],
+ const uint8_t scalar[X448_PRIVATE_BYTES]);
/*
- * Multiply a point by C448_X448_ENCODE_RATIO, then encode it like RFC 7748.
+ * Multiply a point by X448_ENCODE_RATIO, then encode it like RFC 7748.
*
* This function is mainly used internally, but is exported in case
* it will be useful.
*
* As it happens, this aligns with the base point definitions; that is,
* if you pass the Decaf/Ristretto base point to this function, the result
- * will be C448_X448_ENCODE_RATIO times the X448
+ * will be X448_ENCODE_RATIO times the X448
* base point.
*
* out (out): The scaled and encoded point.
* p (in): The point to be scaled and encoded.
*/
void curve448_point_mul_by_ratio_and_encode_like_x448(
- uint8_t out[C448_X448_PUBLIC_BYTES],
+ uint8_t out[X448_PUBLIC_BYTES],
const curve448_point_t p);
/*
* RFC 7748 Diffie-Hellman base point scalarmul. This function uses a different
* (non-Decaf) encoding.
- *
+ *
* out (out): The scaled point base*scalar
* scalar (in): The scalar to multiply by.
*/
-void c448_x448_derive_public_key(
- uint8_t out[C448_X448_PUBLIC_BYTES],
- const uint8_t scalar[C448_X448_PRIVATE_BYTES]);
+void x448_derive_public_key(uint8_t out[X448_PUBLIC_BYTES],
+ const uint8_t scalar[X448_PRIVATE_BYTES]);
/*
* Multiply a precomputed base point by a scalar: out = scalar*base.
* base2 (in): A second point to be scaled.
* scalar2 (in) A second scalar to multiply by.
*
- * Warning: This function takes variable time, and may leak the scalars used.
+ * Warning: This function takes variable time, and may leak the scalars used.
* It is designed for signature verification.
*/
void curve448_base_double_scalarmul_non_secret(curve448_point_t combo,
/* Overwrite point with zeros. */
void curve448_point_destroy(curve448_point_t point);
-#ifdef __cplusplus
-} /* extern "C" */
-#endif
-
-#endif /* __C448_POINT_448_H__ */
+#endif /* HEADER_POINT_448_H */
projects / openssl.git / blobdiff