Diff: wolfssl/wolfcrypt/fe_operations.h

Revision:

13:80fb167dafdf

Parent:

11:cee25a834751

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/wolfssl/wolfcrypt/fe_operations.h	Tue May 30 06:16:19 2017 +0000
@@ -0,0 +1,138 @@
+/* fe_operations.h
+ *
+ * Copyright (C) 2006-2016 wolfSSL Inc.
+ *
+ * This file is part of wolfSSL.
+ *
+ * wolfSSL is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * wolfSSL is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1335, USA
+ */
+
+
+#ifndef WOLF_CRYPT_FE_OPERATIONS_H
+#define WOLF_CRYPT_FE_OPERATIONS_H
+
+#include <wolfssl/wolfcrypt/settings.h>
+
+#if defined(HAVE_CURVE25519) || defined(HAVE_ED25519)
+
+#ifndef CURVED25519_SMALL
+    #include <stdint.h>
+#endif
+#include <wolfssl/wolfcrypt/types.h>
+
+/*
+fe means field element.
+Here the field is \Z/(2^255-19).
+An element t, entries t[0]...t[9], represents the integer
+t[0]+2^26 t[1]+2^51 t[2]+2^77 t[3]+2^102 t[4]+...+2^230 t[9].
+Bounds on each t[i] vary depending on context.
+*/
+
+#ifdef CURVED25519_SMALL
+    #define F25519_SIZE	32
+    typedef byte     fe[32];
+#elif defined(HAVE___UINT128_T)
+    typedef int64_t  fe[5];
+#else
+    typedef int32_t  fe[10];
+#endif
+
+#if! defined FREESCALE_LTC_ECC
+WOLFSSL_LOCAL int  curve25519(byte * q, byte * n, byte * p);
+#endif
+WOLFSSL_LOCAL void fe_copy(fe, const fe);
+WOLFSSL_LOCAL void fe_add(fe, const fe, const fe);
+WOLFSSL_LOCAL void fe_neg(fe,const fe);
+WOLFSSL_LOCAL void fe_sub(fe, const fe, const fe);
+WOLFSSL_LOCAL void fe_invert(fe, const fe);
+WOLFSSL_LOCAL void fe_mul(fe,const fe,const fe);
+
+/* default to be faster but take more memory */
+#ifndef CURVED25519_SMALL
+
+/* Based On Daniel J Bernstein's curve25519 and ed25519 Public Domain ref10
+   work. */
+
+WOLFSSL_LOCAL void fe_0(fe);
+WOLFSSL_LOCAL void fe_1(fe);
+WOLFSSL_LOCAL int  fe_isnonzero(const fe);
+WOLFSSL_LOCAL int  fe_isnegative(const fe);
+WOLFSSL_LOCAL void fe_tobytes(unsigned char *, const fe);
+WOLFSSL_LOCAL void fe_sq(fe, const fe);
+WOLFSSL_LOCAL void fe_sq2(fe,const fe);
+WOLFSSL_LOCAL void fe_frombytes(fe,const unsigned char *);
+WOLFSSL_LOCAL void fe_cswap(fe, fe, int);
+WOLFSSL_LOCAL void fe_mul121666(fe,fe);
+WOLFSSL_LOCAL void fe_cmov(fe,const fe, int);
+WOLFSSL_LOCAL void fe_pow22523(fe,const fe);
+
+/* 64 type needed for SHA512 */
+WOLFSSL_LOCAL uint64_t load_3(const unsigned char *in);
+WOLFSSL_LOCAL uint64_t load_4(const unsigned char *in);
+#endif /* not defined CURVED25519_SMALL */
+
+/* Use less memory and only 32bit types or less, but is slower
+   Based on Daniel Beer's public domain work. */
+#ifdef CURVED25519_SMALL
+static const byte c25519_base_x[F25519_SIZE] = {9};
+static const byte f25519_zero[F25519_SIZE]   = {0};
+static const byte f25519_one[F25519_SIZE]    = {1};
+static const byte fprime_zero[F25519_SIZE]   = {0};
+static const byte fprime_one[F25519_SIZE]    = {1};
+
+WOLFSSL_LOCAL void fe_load(byte *x, word32 c);
+WOLFSSL_LOCAL void fe_normalize(byte *x);
+WOLFSSL_LOCAL void fe_inv__distinct(byte *r, const byte *x);
+
+/* Conditional copy. If condition == 0, then zero is copied to dst. If
+ * condition == 1, then one is copied to dst. Any other value results in
+ * undefined behavior.
+ */
+WOLFSSL_LOCAL void fe_select(byte *dst, const byte *zero, const byte *one,
+		   byte condition);
+
+/* Multiply a point by a small constant. The two pointers are not
+ * required to be distinct.
+ *
+ * The constant must be less than 2^24.
+ */
+WOLFSSL_LOCAL void fe_mul_c(byte *r, const byte *a, word32 b);
+WOLFSSL_LOCAL void fe_mul__distinct(byte *r, const byte *a, const byte *b);
+
+/* Compute one of the square roots of the field element, if the element
+ * is square. The other square is -r.
+ *
+ * If the input is not square, the returned value is a valid field
+ * element, but not the correct answer. If you don't already know that
+ * your element is square, you should square the return value and test.
+ */
+WOLFSSL_LOCAL void fe_sqrt(byte *r, const byte *x);
+
+/* Conditional copy. If condition == 0, then zero is copied to dst. If
+ * condition == 1, then one is copied to dst. Any other value results in
+ * undefined behavior.
+ */
+WOLFSSL_LOCAL void fprime_select(byte *dst, const byte *zero, const byte *one,
+		                         byte condition);
+WOLFSSL_LOCAL void fprime_add(byte *r, const byte *a, const byte *modulus);
+WOLFSSL_LOCAL void fprime_sub(byte *r, const byte *a, const byte *modulus);
+WOLFSSL_LOCAL void fprime_mul(byte *r, const byte *a, const byte *b,
+		                      const byte *modulus);
+WOLFSSL_LOCAL void fprime_copy(byte *x, const byte *a);
+#endif /* CURVED25519_SMALL */
+#endif /* HAVE_CURVE25519 or HAVE_ED25519 */
+#endif /* WOLF_CRYPT_FE_OPERATIONS_H */
+
+