ge_operations.h

00001 /* ge_operations.h
00002  *
00003  * Copyright (C) 2006-2017 wolfSSL Inc.
00004  *
00005  * This file is part of wolfSSL.
00006  *
00007  * wolfSSL is free software; you can redistribute it and/or modify
00008  * it under the terms of the GNU General Public License as published by
00009  * the Free Software Foundation; either version 2 of the License, or
00010  * (at your option) any later version.
00011  *
00012  * wolfSSL is distributed in the hope that it will be useful,
00013  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00014  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00015  * GNU General Public License for more details.
00016  *
00017  * You should have received a copy of the GNU General Public License
00018  * along with this program; if not, write to the Free Software
00019  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1335, USA
00020  */
00021 
00022 
00023  /* Based On Daniel J Bernstein's ed25519 Public Domain ref10 work. */
00024 
00025 #ifndef WOLF_CRYPT_GE_OPERATIONS_H
00026 #define WOLF_CRYPT_GE_OPERATIONS_H
00027 
00028 #include <wolfcrypt/settings.h>
00029 
00030 #ifdef HAVE_ED25519
00031 
00032 #include <wolfcrypt/fe_operations.h>
00033 
00034 /*
00035 ge means group element.
00036 
00037 Here the group is the set of pairs (x,y) of field elements (see fe.h)
00038 satisfying -x^2 + y^2 = 1 + d x^2y^2
00039 where d = -121665/121666.
00040 
00041 Representations:
00042   ge_p2 (projective): (X:Y:Z) satisfying x=X/Z, y=Y/Z
00043   ge_p3 (extended): (X:Y:Z:T) satisfying x=X/Z, y=Y/Z, XY=ZT
00044   ge_p1p1 (completed): ((X:Z),(Y:T)) satisfying x=X/Z, y=Y/T
00045   ge_precomp (Duif): (y+x,y-x,2dxy)
00046 */
00047 
00048 #ifdef ED25519_SMALL
00049   typedef byte     ge[F25519_SIZE];
00050 #elif defined(CURVED25519_X64)
00051   typedef int64_t  ge[4];
00052 #elif defined(CURVED25519_128BIT)
00053   typedef int64_t  ge[5];
00054 #else
00055   typedef int32_t  ge[10];
00056 #endif
00057 
00058 typedef struct {
00059   ge X;
00060   ge Y;
00061   ge Z;
00062 } ge_p2;
00063 
00064 typedef struct {
00065   ge X;
00066   ge Y;
00067   ge Z;
00068   ge T;
00069 } ge_p3;
00070 
00071 
00072 WOLFSSL_LOCAL int  ge_compress_key(byte* out, const byte* xIn, const byte* yIn,
00073                                                                 word32 keySz);
00074 WOLFSSL_LOCAL int  ge_frombytes_negate_vartime(ge_p3 *,const unsigned char *);
00075 
00076 WOLFSSL_LOCAL int  ge_double_scalarmult_vartime(ge_p2 *,const unsigned char *,
00077                                          const ge_p3 *,const unsigned char *);
00078 WOLFSSL_LOCAL void ge_scalarmult_base(ge_p3 *,const unsigned char *);
00079 WOLFSSL_LOCAL void sc_reduce(byte* s);
00080 WOLFSSL_LOCAL void sc_muladd(byte* s, const byte* a, const byte* b,
00081                              const byte* c);
00082 WOLFSSL_LOCAL void ge_tobytes(unsigned char *,const ge_p2 *);
00083 WOLFSSL_LOCAL void ge_p3_tobytes(unsigned char *,const ge_p3 *);
00084 
00085 
00086 #ifndef ED25519_SMALL
00087 typedef struct {
00088   ge X;
00089   ge Y;
00090   ge Z;
00091   ge T;
00092 } ge_p1p1;
00093 
00094 typedef struct {
00095   ge yplusx;
00096   ge yminusx;
00097   ge xy2d;
00098 } ge_precomp;
00099 
00100 typedef struct {
00101   ge YplusX;
00102   ge YminusX;
00103   ge Z;
00104   ge T2d;
00105 } ge_cached;
00106 
00107 #endif /* !ED25519_SMALL */
00108 
00109 #endif /* HAVE_ED25519 */
00110 
00111 #endif /* WOLF_CRYPT_GE_OPERATIONS_H */
00112