eckey_impl.h (3958B)
1 /*********************************************************************** 2 * Copyright (c) 2013, 2014 Pieter Wuille * 3 * Distributed under the MIT software license, see the accompanying * 4 * file COPYING or https://www.opensource.org/licenses/mit-license.php.* 5 ***********************************************************************/ 6 7 #ifndef SECP256K1_ECKEY_IMPL_H 8 #define SECP256K1_ECKEY_IMPL_H 9 10 #include "eckey.h" 11 12 #include "scalar.h" 13 #include "field.h" 14 #include "group.h" 15 #include "ecmult_gen.h" 16 17 static int haskellsecp256k1_v0_1_0_eckey_pubkey_parse(haskellsecp256k1_v0_1_0_ge *elem, const unsigned char *pub, size_t size) { 18 if (size == 33 && (pub[0] == SECP256K1_TAG_PUBKEY_EVEN || pub[0] == SECP256K1_TAG_PUBKEY_ODD)) { 19 haskellsecp256k1_v0_1_0_fe x; 20 return haskellsecp256k1_v0_1_0_fe_set_b32_limit(&x, pub+1) && haskellsecp256k1_v0_1_0_ge_set_xo_var(elem, &x, pub[0] == SECP256K1_TAG_PUBKEY_ODD); 21 } else if (size == 65 && (pub[0] == SECP256K1_TAG_PUBKEY_UNCOMPRESSED || pub[0] == SECP256K1_TAG_PUBKEY_HYBRID_EVEN || pub[0] == SECP256K1_TAG_PUBKEY_HYBRID_ODD)) { 22 haskellsecp256k1_v0_1_0_fe x, y; 23 if (!haskellsecp256k1_v0_1_0_fe_set_b32_limit(&x, pub+1) || !haskellsecp256k1_v0_1_0_fe_set_b32_limit(&y, pub+33)) { 24 return 0; 25 } 26 haskellsecp256k1_v0_1_0_ge_set_xy(elem, &x, &y); 27 if ((pub[0] == SECP256K1_TAG_PUBKEY_HYBRID_EVEN || pub[0] == SECP256K1_TAG_PUBKEY_HYBRID_ODD) && 28 haskellsecp256k1_v0_1_0_fe_is_odd(&y) != (pub[0] == SECP256K1_TAG_PUBKEY_HYBRID_ODD)) { 29 return 0; 30 } 31 return haskellsecp256k1_v0_1_0_ge_is_valid_var(elem); 32 } else { 33 return 0; 34 } 35 } 36 37 static int haskellsecp256k1_v0_1_0_eckey_pubkey_serialize(haskellsecp256k1_v0_1_0_ge *elem, unsigned char *pub, size_t *size, int compressed) { 38 if (haskellsecp256k1_v0_1_0_ge_is_infinity(elem)) { 39 return 0; 40 } 41 haskellsecp256k1_v0_1_0_fe_normalize_var(&elem->x); 42 haskellsecp256k1_v0_1_0_fe_normalize_var(&elem->y); 43 haskellsecp256k1_v0_1_0_fe_get_b32(&pub[1], &elem->x); 44 if (compressed) { 45 *size = 33; 46 pub[0] = haskellsecp256k1_v0_1_0_fe_is_odd(&elem->y) ? SECP256K1_TAG_PUBKEY_ODD : SECP256K1_TAG_PUBKEY_EVEN; 47 } else { 48 *size = 65; 49 pub[0] = SECP256K1_TAG_PUBKEY_UNCOMPRESSED; 50 haskellsecp256k1_v0_1_0_fe_get_b32(&pub[33], &elem->y); 51 } 52 return 1; 53 } 54 55 static int haskellsecp256k1_v0_1_0_eckey_privkey_tweak_add(haskellsecp256k1_v0_1_0_scalar *key, const haskellsecp256k1_v0_1_0_scalar *tweak) { 56 haskellsecp256k1_v0_1_0_scalar_add(key, key, tweak); 57 return !haskellsecp256k1_v0_1_0_scalar_is_zero(key); 58 } 59 60 static int haskellsecp256k1_v0_1_0_eckey_pubkey_tweak_add(haskellsecp256k1_v0_1_0_ge *key, const haskellsecp256k1_v0_1_0_scalar *tweak) { 61 haskellsecp256k1_v0_1_0_gej pt; 62 haskellsecp256k1_v0_1_0_gej_set_ge(&pt, key); 63 haskellsecp256k1_v0_1_0_ecmult(&pt, &pt, &haskellsecp256k1_v0_1_0_scalar_one, tweak); 64 65 if (haskellsecp256k1_v0_1_0_gej_is_infinity(&pt)) { 66 return 0; 67 } 68 haskellsecp256k1_v0_1_0_ge_set_gej(key, &pt); 69 return 1; 70 } 71 72 static int haskellsecp256k1_v0_1_0_eckey_privkey_tweak_mul(haskellsecp256k1_v0_1_0_scalar *key, const haskellsecp256k1_v0_1_0_scalar *tweak) { 73 int ret; 74 ret = !haskellsecp256k1_v0_1_0_scalar_is_zero(tweak); 75 76 haskellsecp256k1_v0_1_0_scalar_mul(key, key, tweak); 77 return ret; 78 } 79 80 static int haskellsecp256k1_v0_1_0_eckey_pubkey_tweak_mul(haskellsecp256k1_v0_1_0_ge *key, const haskellsecp256k1_v0_1_0_scalar *tweak) { 81 haskellsecp256k1_v0_1_0_gej pt; 82 if (haskellsecp256k1_v0_1_0_scalar_is_zero(tweak)) { 83 return 0; 84 } 85 86 haskellsecp256k1_v0_1_0_gej_set_ge(&pt, key); 87 haskellsecp256k1_v0_1_0_ecmult(&pt, &pt, tweak, &haskellsecp256k1_v0_1_0_scalar_zero); 88 haskellsecp256k1_v0_1_0_ge_set_gej(key, &pt); 89 return 1; 90 } 91 92 #endif /* SECP256K1_ECKEY_IMPL_H */