1 /* Copyright (c) 2015, Google Inc. 2 * 3 * Permission to use, copy, modify, and/or distribute this software for any 4 * purpose with or without fee is hereby granted, provided that the above 5 * copyright notice and this permission notice appear in all copies. 6 * 7 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 8 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 9 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY 10 * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 11 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION 12 * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN 13 * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ 14 15 #ifndef OPENSSL_HEADER_CURVE25519_INTERNAL_H 16 #define OPENSSL_HEADER_CURVE25519_INTERNAL_H 17 18 #if defined(__cplusplus) 19 extern "C" { 20 #endif 21 22 23 #if defined(OPENSSL_X86_64) && !defined(OPENSSL_SMALL) && \ 24 !defined(OPENSSL_WINDOWS) && !defined(OPENSSL_NO_ASM) 25 #define BORINGSSL_X25519_X86_64 26 27 void x25519_x86_64(uint8_t out[32], const uint8_t scalar[32], 28 const uint8_t point[32]); 29 #endif 30 31 32 #if defined(OPENSSL_ARM) && !defined(OPENSSL_NO_ASM) && !defined(OPENSSL_APPLE) 33 #define BORINGSSL_X25519_NEON 34 35 /* x25519_NEON is defined in asm/x25519-arm.S. */ 36 void x25519_NEON(uint8_t out[32], const uint8_t scalar[32], 37 const uint8_t point[32]); 38 #endif 39 40 /* fe means field element. Here the field is \Z/(2^255-19). An element t, 41 * entries t[0]...t[9], represents the integer t[0]+2^26 t[1]+2^51 t[2]+2^77 42 * t[3]+2^102 t[4]+...+2^230 t[9]. Bounds on each t[i] vary depending on 43 * context. */ 44 typedef int32_t fe[10]; 45 46 /* ge means group element. 47 48 * Here the group is the set of pairs (x,y) of field elements (see fe.h) 49 * satisfying -x^2 + y^2 = 1 + d x^2y^2 50 * where d = -121665/121666. 51 * 52 * Representations: 53 * ge_p2 (projective): (X:Y:Z) satisfying x=X/Z, y=Y/Z 54 * ge_p3 (extended): (X:Y:Z:T) satisfying x=X/Z, y=Y/Z, XY=ZT 55 * ge_p1p1 (completed): ((X:Z),(Y:T)) satisfying x=X/Z, y=Y/T 56 * ge_precomp (Duif): (y+x,y-x,2dxy) */ 57 58 typedef struct { 59 fe X; 60 fe Y; 61 fe Z; 62 } ge_p2; 63 64 typedef struct { 65 fe X; 66 fe Y; 67 fe Z; 68 fe T; 69 } ge_p3; 70 71 typedef struct { 72 fe X; 73 fe Y; 74 fe Z; 75 fe T; 76 } ge_p1p1; 77 78 typedef struct { 79 fe yplusx; 80 fe yminusx; 81 fe xy2d; 82 } ge_precomp; 83 84 typedef struct { 85 fe YplusX; 86 fe YminusX; 87 fe Z; 88 fe T2d; 89 } ge_cached; 90 91 void x25519_ge_tobytes(uint8_t *s, const ge_p2 *h); 92 int x25519_ge_frombytes_vartime(ge_p3 *h, const uint8_t *s); 93 void x25519_ge_p3_to_cached(ge_cached *r, const ge_p3 *p); 94 void x25519_ge_p1p1_to_p2(ge_p2 *r, const ge_p1p1 *p); 95 void x25519_ge_p1p1_to_p3(ge_p3 *r, const ge_p1p1 *p); 96 void x25519_ge_add(ge_p1p1 *r, const ge_p3 *p, const ge_cached *q); 97 void x25519_ge_sub(ge_p1p1 *r, const ge_p3 *p, const ge_cached *q); 98 void x25519_ge_scalarmult_small_precomp( 99 ge_p3 *h, const uint8_t a[32], const uint8_t precomp_table[15 * 2 * 32]); 100 void x25519_ge_scalarmult_base(ge_p3 *h, const uint8_t a[32]); 101 void x25519_ge_scalarmult(ge_p2 *r, const uint8_t *scalar, const ge_p3 *A); 102 void x25519_sc_reduce(uint8_t *s); 103 104 105 #if defined(__cplusplus) 106 } /* extern C */ 107 #endif 108 109 #endif /* OPENSSL_HEADER_CURVE25519_INTERNAL_H */ 110