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597 lines
20 KiB
597 lines
20 KiB
/********************************************************************** |
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* Copyright (c) 2013-2015 Pieter Wuille * |
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* Distributed under the MIT software license, see the accompanying * |
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* file COPYING or http://www.opensource.org/licenses/mit-license.php.* |
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**********************************************************************/ |
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#include "include/secp256k1.h" |
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#include "util.h" |
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#include "num_impl.h" |
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#include "field_impl.h" |
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#include "scalar_impl.h" |
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#include "group_impl.h" |
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#include "ecmult_impl.h" |
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#include "ecmult_const_impl.h" |
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#include "ecmult_gen_impl.h" |
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#include "ecdsa_impl.h" |
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#include "eckey_impl.h" |
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#include "hash_impl.h" |
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#include "scratch_impl.h" |
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#define ARG_CHECK(cond) do { \ |
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if (EXPECT(!(cond), 0)) { \ |
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secp256k1_callback_call(&ctx->illegal_callback, #cond); \ |
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return 0; \ |
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} \ |
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} while(0) |
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static void default_illegal_callback_fn(const char* str, void* data) { |
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(void)data; |
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fprintf(stderr, "[libsecp256k1] illegal argument: %s\n", str); |
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abort(); |
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} |
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static const secp256k1_callback default_illegal_callback = { |
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default_illegal_callback_fn, |
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NULL |
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}; |
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static void default_error_callback_fn(const char* str, void* data) { |
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(void)data; |
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fprintf(stderr, "[libsecp256k1] internal consistency check failed: %s\n", str); |
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abort(); |
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} |
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static const secp256k1_callback default_error_callback = { |
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default_error_callback_fn, |
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NULL |
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}; |
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struct secp256k1_context_struct { |
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secp256k1_ecmult_context ecmult_ctx; |
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secp256k1_ecmult_gen_context ecmult_gen_ctx; |
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secp256k1_callback illegal_callback; |
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secp256k1_callback error_callback; |
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}; |
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secp256k1_context* secp256k1_context_create(unsigned int flags) { |
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secp256k1_context* ret = (secp256k1_context*)checked_malloc(&default_error_callback, sizeof(secp256k1_context)); |
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ret->illegal_callback = default_illegal_callback; |
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ret->error_callback = default_error_callback; |
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if (EXPECT((flags & SECP256K1_FLAGS_TYPE_MASK) != SECP256K1_FLAGS_TYPE_CONTEXT, 0)) { |
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secp256k1_callback_call(&ret->illegal_callback, |
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"Invalid flags"); |
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free(ret); |
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return NULL; |
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} |
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secp256k1_ecmult_context_init(&ret->ecmult_ctx); |
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secp256k1_ecmult_gen_context_init(&ret->ecmult_gen_ctx); |
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if (flags & SECP256K1_FLAGS_BIT_CONTEXT_SIGN) { |
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secp256k1_ecmult_gen_context_build(&ret->ecmult_gen_ctx, &ret->error_callback); |
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} |
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if (flags & SECP256K1_FLAGS_BIT_CONTEXT_VERIFY) { |
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secp256k1_ecmult_context_build(&ret->ecmult_ctx, &ret->error_callback); |
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} |
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return ret; |
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} |
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secp256k1_context* secp256k1_context_clone(const secp256k1_context* ctx) { |
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secp256k1_context* ret = (secp256k1_context*)checked_malloc(&ctx->error_callback, sizeof(secp256k1_context)); |
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ret->illegal_callback = ctx->illegal_callback; |
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ret->error_callback = ctx->error_callback; |
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secp256k1_ecmult_context_clone(&ret->ecmult_ctx, &ctx->ecmult_ctx, &ctx->error_callback); |
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secp256k1_ecmult_gen_context_clone(&ret->ecmult_gen_ctx, &ctx->ecmult_gen_ctx, &ctx->error_callback); |
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return ret; |
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} |
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void secp256k1_context_destroy(secp256k1_context* ctx) { |
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if (ctx != NULL) { |
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secp256k1_ecmult_context_clear(&ctx->ecmult_ctx); |
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secp256k1_ecmult_gen_context_clear(&ctx->ecmult_gen_ctx); |
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free(ctx); |
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} |
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} |
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void secp256k1_context_set_illegal_callback(secp256k1_context* ctx, void (*fun)(const char* message, void* data), const void* data) { |
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if (fun == NULL) { |
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fun = default_illegal_callback_fn; |
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} |
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ctx->illegal_callback.fn = fun; |
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ctx->illegal_callback.data = data; |
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} |
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void secp256k1_context_set_error_callback(secp256k1_context* ctx, void (*fun)(const char* message, void* data), const void* data) { |
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if (fun == NULL) { |
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fun = default_error_callback_fn; |
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} |
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ctx->error_callback.fn = fun; |
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ctx->error_callback.data = data; |
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} |
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secp256k1_scratch_space* secp256k1_scratch_space_create(const secp256k1_context* ctx, size_t max_size) { |
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VERIFY_CHECK(ctx != NULL); |
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return secp256k1_scratch_create(&ctx->error_callback, max_size); |
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} |
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void secp256k1_scratch_space_destroy(secp256k1_scratch_space* scratch) { |
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secp256k1_scratch_destroy(scratch); |
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} |
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static int secp256k1_pubkey_load(const secp256k1_context* ctx, secp256k1_ge* ge, const secp256k1_pubkey* pubkey) { |
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if (sizeof(secp256k1_ge_storage) == 64) { |
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/* When the secp256k1_ge_storage type is exactly 64 byte, use its |
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* representation inside secp256k1_pubkey, as conversion is very fast. |
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* Note that secp256k1_pubkey_save must use the same representation. */ |
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secp256k1_ge_storage s; |
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memcpy(&s, &pubkey->data[0], sizeof(s)); |
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secp256k1_ge_from_storage(ge, &s); |
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} else { |
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/* Otherwise, fall back to 32-byte big endian for X and Y. */ |
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secp256k1_fe x, y; |
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secp256k1_fe_set_b32(&x, pubkey->data); |
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secp256k1_fe_set_b32(&y, pubkey->data + 32); |
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secp256k1_ge_set_xy(ge, &x, &y); |
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} |
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ARG_CHECK(!secp256k1_fe_is_zero(&ge->x)); |
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return 1; |
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} |
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static void secp256k1_pubkey_save(secp256k1_pubkey* pubkey, secp256k1_ge* ge) { |
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if (sizeof(secp256k1_ge_storage) == 64) { |
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secp256k1_ge_storage s; |
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secp256k1_ge_to_storage(&s, ge); |
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memcpy(&pubkey->data[0], &s, sizeof(s)); |
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} else { |
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VERIFY_CHECK(!secp256k1_ge_is_infinity(ge)); |
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secp256k1_fe_normalize_var(&ge->x); |
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secp256k1_fe_normalize_var(&ge->y); |
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secp256k1_fe_get_b32(pubkey->data, &ge->x); |
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secp256k1_fe_get_b32(pubkey->data + 32, &ge->y); |
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} |
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} |
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int secp256k1_ec_pubkey_parse(const secp256k1_context* ctx, secp256k1_pubkey* pubkey, const unsigned char *input, size_t inputlen) { |
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secp256k1_ge Q; |
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VERIFY_CHECK(ctx != NULL); |
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ARG_CHECK(pubkey != NULL); |
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memset(pubkey, 0, sizeof(*pubkey)); |
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ARG_CHECK(input != NULL); |
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if (!secp256k1_eckey_pubkey_parse(&Q, input, inputlen)) { |
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return 0; |
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} |
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secp256k1_pubkey_save(pubkey, &Q); |
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secp256k1_ge_clear(&Q); |
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return 1; |
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} |
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int secp256k1_ec_pubkey_serialize(const secp256k1_context* ctx, unsigned char *output, size_t *outputlen, const secp256k1_pubkey* pubkey, unsigned int flags) { |
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secp256k1_ge Q; |
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size_t len; |
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int ret = 0; |
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VERIFY_CHECK(ctx != NULL); |
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ARG_CHECK(outputlen != NULL); |
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ARG_CHECK(*outputlen >= ((flags & SECP256K1_FLAGS_BIT_COMPRESSION) ? 33 : 65)); |
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len = *outputlen; |
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*outputlen = 0; |
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ARG_CHECK(output != NULL); |
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memset(output, 0, len); |
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ARG_CHECK(pubkey != NULL); |
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ARG_CHECK((flags & SECP256K1_FLAGS_TYPE_MASK) == SECP256K1_FLAGS_TYPE_COMPRESSION); |
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if (secp256k1_pubkey_load(ctx, &Q, pubkey)) { |
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ret = secp256k1_eckey_pubkey_serialize(&Q, output, &len, flags & SECP256K1_FLAGS_BIT_COMPRESSION); |
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if (ret) { |
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*outputlen = len; |
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} |
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} |
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return ret; |
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} |
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static void secp256k1_ecdsa_signature_load(const secp256k1_context* ctx, secp256k1_scalar* r, secp256k1_scalar* s, const secp256k1_ecdsa_signature* sig) { |
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(void)ctx; |
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if (sizeof(secp256k1_scalar) == 32) { |
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/* When the secp256k1_scalar type is exactly 32 byte, use its |
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* representation inside secp256k1_ecdsa_signature, as conversion is very fast. |
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* Note that secp256k1_ecdsa_signature_save must use the same representation. */ |
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memcpy(r, &sig->data[0], 32); |
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memcpy(s, &sig->data[32], 32); |
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} else { |
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secp256k1_scalar_set_b32(r, &sig->data[0], NULL); |
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secp256k1_scalar_set_b32(s, &sig->data[32], NULL); |
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} |
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} |
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static void secp256k1_ecdsa_signature_save(secp256k1_ecdsa_signature* sig, const secp256k1_scalar* r, const secp256k1_scalar* s) { |
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if (sizeof(secp256k1_scalar) == 32) { |
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memcpy(&sig->data[0], r, 32); |
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memcpy(&sig->data[32], s, 32); |
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} else { |
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secp256k1_scalar_get_b32(&sig->data[0], r); |
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secp256k1_scalar_get_b32(&sig->data[32], s); |
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} |
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} |
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int secp256k1_ecdsa_signature_parse_der(const secp256k1_context* ctx, secp256k1_ecdsa_signature* sig, const unsigned char *input, size_t inputlen) { |
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secp256k1_scalar r, s; |
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VERIFY_CHECK(ctx != NULL); |
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ARG_CHECK(sig != NULL); |
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ARG_CHECK(input != NULL); |
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if (secp256k1_ecdsa_sig_parse(&r, &s, input, inputlen)) { |
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secp256k1_ecdsa_signature_save(sig, &r, &s); |
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return 1; |
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} else { |
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memset(sig, 0, sizeof(*sig)); |
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return 0; |
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} |
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} |
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int secp256k1_ecdsa_signature_parse_compact(const secp256k1_context* ctx, secp256k1_ecdsa_signature* sig, const unsigned char *input64) { |
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secp256k1_scalar r, s; |
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int ret = 1; |
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int overflow = 0; |
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VERIFY_CHECK(ctx != NULL); |
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ARG_CHECK(sig != NULL); |
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ARG_CHECK(input64 != NULL); |
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secp256k1_scalar_set_b32(&r, &input64[0], &overflow); |
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ret &= !overflow; |
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secp256k1_scalar_set_b32(&s, &input64[32], &overflow); |
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ret &= !overflow; |
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if (ret) { |
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secp256k1_ecdsa_signature_save(sig, &r, &s); |
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} else { |
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memset(sig, 0, sizeof(*sig)); |
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} |
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return ret; |
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} |
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int secp256k1_ecdsa_signature_serialize_der(const secp256k1_context* ctx, unsigned char *output, size_t *outputlen, const secp256k1_ecdsa_signature* sig) { |
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secp256k1_scalar r, s; |
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VERIFY_CHECK(ctx != NULL); |
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ARG_CHECK(output != NULL); |
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ARG_CHECK(outputlen != NULL); |
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ARG_CHECK(sig != NULL); |
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secp256k1_ecdsa_signature_load(ctx, &r, &s, sig); |
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return secp256k1_ecdsa_sig_serialize(output, outputlen, &r, &s); |
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} |
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int secp256k1_ecdsa_signature_serialize_compact(const secp256k1_context* ctx, unsigned char *output64, const secp256k1_ecdsa_signature* sig) { |
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secp256k1_scalar r, s; |
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VERIFY_CHECK(ctx != NULL); |
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ARG_CHECK(output64 != NULL); |
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ARG_CHECK(sig != NULL); |
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secp256k1_ecdsa_signature_load(ctx, &r, &s, sig); |
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secp256k1_scalar_get_b32(&output64[0], &r); |
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secp256k1_scalar_get_b32(&output64[32], &s); |
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return 1; |
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} |
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int secp256k1_ecdsa_signature_normalize(const secp256k1_context* ctx, secp256k1_ecdsa_signature *sigout, const secp256k1_ecdsa_signature *sigin) { |
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secp256k1_scalar r, s; |
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int ret = 0; |
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VERIFY_CHECK(ctx != NULL); |
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ARG_CHECK(sigin != NULL); |
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secp256k1_ecdsa_signature_load(ctx, &r, &s, sigin); |
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ret = secp256k1_scalar_is_high(&s); |
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if (sigout != NULL) { |
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if (ret) { |
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secp256k1_scalar_negate(&s, &s); |
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} |
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secp256k1_ecdsa_signature_save(sigout, &r, &s); |
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} |
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return ret; |
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} |
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int secp256k1_ecdsa_verify(const secp256k1_context* ctx, const secp256k1_ecdsa_signature *sig, const unsigned char *msg32, const secp256k1_pubkey *pubkey) { |
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secp256k1_ge q; |
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secp256k1_scalar r, s; |
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secp256k1_scalar m; |
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VERIFY_CHECK(ctx != NULL); |
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ARG_CHECK(secp256k1_ecmult_context_is_built(&ctx->ecmult_ctx)); |
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ARG_CHECK(msg32 != NULL); |
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ARG_CHECK(sig != NULL); |
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ARG_CHECK(pubkey != NULL); |
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secp256k1_scalar_set_b32(&m, msg32, NULL); |
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secp256k1_ecdsa_signature_load(ctx, &r, &s, sig); |
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return (!secp256k1_scalar_is_high(&s) && |
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secp256k1_pubkey_load(ctx, &q, pubkey) && |
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secp256k1_ecdsa_sig_verify(&ctx->ecmult_ctx, &r, &s, &q, &m)); |
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} |
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static SECP256K1_INLINE void buffer_append(unsigned char *buf, unsigned int *offset, const void *data, unsigned int len) { |
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memcpy(buf + *offset, data, len); |
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*offset += len; |
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} |
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static int nonce_function_rfc6979(unsigned char *nonce32, const unsigned char *msg32, const unsigned char *key32, const unsigned char *algo16, void *data, unsigned int counter) { |
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unsigned char keydata[112]; |
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unsigned int offset = 0; |
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secp256k1_rfc6979_hmac_sha256 rng; |
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unsigned int i; |
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/* We feed a byte array to the PRNG as input, consisting of: |
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* - the private key (32 bytes) and message (32 bytes), see RFC 6979 3.2d. |
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* - optionally 32 extra bytes of data, see RFC 6979 3.6 Additional Data. |
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* - optionally 16 extra bytes with the algorithm name. |
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* Because the arguments have distinct fixed lengths it is not possible for |
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* different argument mixtures to emulate each other and result in the same |
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* nonces. |
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*/ |
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buffer_append(keydata, &offset, key32, 32); |
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buffer_append(keydata, &offset, msg32, 32); |
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if (data != NULL) { |
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buffer_append(keydata, &offset, data, 32); |
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} |
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if (algo16 != NULL) { |
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buffer_append(keydata, &offset, algo16, 16); |
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} |
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secp256k1_rfc6979_hmac_sha256_initialize(&rng, keydata, offset); |
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memset(keydata, 0, sizeof(keydata)); |
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for (i = 0; i <= counter; i++) { |
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secp256k1_rfc6979_hmac_sha256_generate(&rng, nonce32, 32); |
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} |
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secp256k1_rfc6979_hmac_sha256_finalize(&rng); |
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return 1; |
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} |
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const secp256k1_nonce_function secp256k1_nonce_function_rfc6979 = nonce_function_rfc6979; |
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const secp256k1_nonce_function secp256k1_nonce_function_default = nonce_function_rfc6979; |
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int secp256k1_ecdsa_sign(const secp256k1_context* ctx, secp256k1_ecdsa_signature *signature, const unsigned char *msg32, const unsigned char *seckey, secp256k1_nonce_function noncefp, const void* noncedata) { |
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secp256k1_scalar r, s; |
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secp256k1_scalar sec, non, msg; |
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int ret = 0; |
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int overflow = 0; |
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VERIFY_CHECK(ctx != NULL); |
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ARG_CHECK(secp256k1_ecmult_gen_context_is_built(&ctx->ecmult_gen_ctx)); |
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ARG_CHECK(msg32 != NULL); |
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ARG_CHECK(signature != NULL); |
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ARG_CHECK(seckey != NULL); |
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if (noncefp == NULL) { |
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noncefp = secp256k1_nonce_function_default; |
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} |
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secp256k1_scalar_set_b32(&sec, seckey, &overflow); |
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/* Fail if the secret key is invalid. */ |
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if (!overflow && !secp256k1_scalar_is_zero(&sec)) { |
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unsigned char nonce32[32]; |
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unsigned int count = 0; |
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secp256k1_scalar_set_b32(&msg, msg32, NULL); |
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while (1) { |
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ret = noncefp(nonce32, msg32, seckey, NULL, (void*)noncedata, count); |
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if (!ret) { |
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break; |
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} |
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secp256k1_scalar_set_b32(&non, nonce32, &overflow); |
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if (!overflow && !secp256k1_scalar_is_zero(&non)) { |
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if (secp256k1_ecdsa_sig_sign(&ctx->ecmult_gen_ctx, &r, &s, &sec, &msg, &non, NULL)) { |
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break; |
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} |
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} |
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count++; |
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} |
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memset(nonce32, 0, 32); |
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secp256k1_scalar_clear(&msg); |
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secp256k1_scalar_clear(&non); |
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secp256k1_scalar_clear(&sec); |
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} |
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if (ret) { |
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secp256k1_ecdsa_signature_save(signature, &r, &s); |
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} else { |
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memset(signature, 0, sizeof(*signature)); |
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} |
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return ret; |
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} |
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int secp256k1_ec_seckey_verify(const secp256k1_context* ctx, const unsigned char *seckey) { |
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secp256k1_scalar sec; |
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int ret; |
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int overflow; |
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VERIFY_CHECK(ctx != NULL); |
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ARG_CHECK(seckey != NULL); |
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secp256k1_scalar_set_b32(&sec, seckey, &overflow); |
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ret = !overflow && !secp256k1_scalar_is_zero(&sec); |
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secp256k1_scalar_clear(&sec); |
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return ret; |
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} |
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int secp256k1_ec_pubkey_create(const secp256k1_context* ctx, secp256k1_pubkey *pubkey, const unsigned char *seckey) { |
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secp256k1_gej pj; |
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secp256k1_ge p; |
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secp256k1_scalar sec; |
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int overflow; |
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int ret = 0; |
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VERIFY_CHECK(ctx != NULL); |
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ARG_CHECK(pubkey != NULL); |
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memset(pubkey, 0, sizeof(*pubkey)); |
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ARG_CHECK(secp256k1_ecmult_gen_context_is_built(&ctx->ecmult_gen_ctx)); |
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ARG_CHECK(seckey != NULL); |
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secp256k1_scalar_set_b32(&sec, seckey, &overflow); |
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ret = (!overflow) & (!secp256k1_scalar_is_zero(&sec)); |
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if (ret) { |
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secp256k1_ecmult_gen(&ctx->ecmult_gen_ctx, &pj, &sec); |
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secp256k1_ge_set_gej(&p, &pj); |
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secp256k1_pubkey_save(pubkey, &p); |
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} |
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secp256k1_scalar_clear(&sec); |
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return ret; |
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} |
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int secp256k1_ec_privkey_negate(const secp256k1_context* ctx, unsigned char *seckey) { |
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secp256k1_scalar sec; |
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VERIFY_CHECK(ctx != NULL); |
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ARG_CHECK(seckey != NULL); |
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secp256k1_scalar_set_b32(&sec, seckey, NULL); |
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secp256k1_scalar_negate(&sec, &sec); |
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secp256k1_scalar_get_b32(seckey, &sec); |
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return 1; |
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} |
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int secp256k1_ec_pubkey_negate(const secp256k1_context* ctx, secp256k1_pubkey *pubkey) { |
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int ret = 0; |
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secp256k1_ge p; |
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VERIFY_CHECK(ctx != NULL); |
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ARG_CHECK(pubkey != NULL); |
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ret = secp256k1_pubkey_load(ctx, &p, pubkey); |
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memset(pubkey, 0, sizeof(*pubkey)); |
|
if (ret) { |
|
secp256k1_ge_neg(&p, &p); |
|
secp256k1_pubkey_save(pubkey, &p); |
|
} |
|
return ret; |
|
} |
|
|
|
int secp256k1_ec_privkey_tweak_add(const secp256k1_context* ctx, unsigned char *seckey, const unsigned char *tweak) { |
|
secp256k1_scalar term; |
|
secp256k1_scalar sec; |
|
int ret = 0; |
|
int overflow = 0; |
|
VERIFY_CHECK(ctx != NULL); |
|
ARG_CHECK(seckey != NULL); |
|
ARG_CHECK(tweak != NULL); |
|
|
|
secp256k1_scalar_set_b32(&term, tweak, &overflow); |
|
secp256k1_scalar_set_b32(&sec, seckey, NULL); |
|
|
|
ret = !overflow && secp256k1_eckey_privkey_tweak_add(&sec, &term); |
|
memset(seckey, 0, 32); |
|
if (ret) { |
|
secp256k1_scalar_get_b32(seckey, &sec); |
|
} |
|
|
|
secp256k1_scalar_clear(&sec); |
|
secp256k1_scalar_clear(&term); |
|
return ret; |
|
} |
|
|
|
int secp256k1_ec_pubkey_tweak_add(const secp256k1_context* ctx, secp256k1_pubkey *pubkey, const unsigned char *tweak) { |
|
secp256k1_ge p; |
|
secp256k1_scalar term; |
|
int ret = 0; |
|
int overflow = 0; |
|
VERIFY_CHECK(ctx != NULL); |
|
ARG_CHECK(secp256k1_ecmult_context_is_built(&ctx->ecmult_ctx)); |
|
ARG_CHECK(pubkey != NULL); |
|
ARG_CHECK(tweak != NULL); |
|
|
|
secp256k1_scalar_set_b32(&term, tweak, &overflow); |
|
ret = !overflow && secp256k1_pubkey_load(ctx, &p, pubkey); |
|
memset(pubkey, 0, sizeof(*pubkey)); |
|
if (ret) { |
|
if (secp256k1_eckey_pubkey_tweak_add(&ctx->ecmult_ctx, &p, &term)) { |
|
secp256k1_pubkey_save(pubkey, &p); |
|
} else { |
|
ret = 0; |
|
} |
|
} |
|
|
|
return ret; |
|
} |
|
|
|
int secp256k1_ec_privkey_tweak_mul(const secp256k1_context* ctx, unsigned char *seckey, const unsigned char *tweak) { |
|
secp256k1_scalar factor; |
|
secp256k1_scalar sec; |
|
int ret = 0; |
|
int overflow = 0; |
|
VERIFY_CHECK(ctx != NULL); |
|
ARG_CHECK(seckey != NULL); |
|
ARG_CHECK(tweak != NULL); |
|
|
|
secp256k1_scalar_set_b32(&factor, tweak, &overflow); |
|
secp256k1_scalar_set_b32(&sec, seckey, NULL); |
|
ret = !overflow && secp256k1_eckey_privkey_tweak_mul(&sec, &factor); |
|
memset(seckey, 0, 32); |
|
if (ret) { |
|
secp256k1_scalar_get_b32(seckey, &sec); |
|
} |
|
|
|
secp256k1_scalar_clear(&sec); |
|
secp256k1_scalar_clear(&factor); |
|
return ret; |
|
} |
|
|
|
int secp256k1_ec_pubkey_tweak_mul(const secp256k1_context* ctx, secp256k1_pubkey *pubkey, const unsigned char *tweak) { |
|
secp256k1_ge p; |
|
secp256k1_scalar factor; |
|
int ret = 0; |
|
int overflow = 0; |
|
VERIFY_CHECK(ctx != NULL); |
|
ARG_CHECK(secp256k1_ecmult_context_is_built(&ctx->ecmult_ctx)); |
|
ARG_CHECK(pubkey != NULL); |
|
ARG_CHECK(tweak != NULL); |
|
|
|
secp256k1_scalar_set_b32(&factor, tweak, &overflow); |
|
ret = !overflow && secp256k1_pubkey_load(ctx, &p, pubkey); |
|
memset(pubkey, 0, sizeof(*pubkey)); |
|
if (ret) { |
|
if (secp256k1_eckey_pubkey_tweak_mul(&ctx->ecmult_ctx, &p, &factor)) { |
|
secp256k1_pubkey_save(pubkey, &p); |
|
} else { |
|
ret = 0; |
|
} |
|
} |
|
|
|
return ret; |
|
} |
|
|
|
int secp256k1_context_randomize(secp256k1_context* ctx, const unsigned char *seed32) { |
|
VERIFY_CHECK(ctx != NULL); |
|
ARG_CHECK(secp256k1_ecmult_gen_context_is_built(&ctx->ecmult_gen_ctx)); |
|
secp256k1_ecmult_gen_blind(&ctx->ecmult_gen_ctx, seed32); |
|
return 1; |
|
} |
|
|
|
int secp256k1_ec_pubkey_combine(const secp256k1_context* ctx, secp256k1_pubkey *pubnonce, const secp256k1_pubkey * const *pubnonces, size_t n) { |
|
size_t i; |
|
secp256k1_gej Qj; |
|
secp256k1_ge Q; |
|
|
|
ARG_CHECK(pubnonce != NULL); |
|
memset(pubnonce, 0, sizeof(*pubnonce)); |
|
ARG_CHECK(n >= 1); |
|
ARG_CHECK(pubnonces != NULL); |
|
|
|
secp256k1_gej_set_infinity(&Qj); |
|
|
|
for (i = 0; i < n; i++) { |
|
secp256k1_pubkey_load(ctx, &Q, pubnonces[i]); |
|
secp256k1_gej_add_ge(&Qj, &Qj, &Q); |
|
} |
|
if (secp256k1_gej_is_infinity(&Qj)) { |
|
return 0; |
|
} |
|
secp256k1_ge_set_gej(&Q, &Qj); |
|
secp256k1_pubkey_save(pubnonce, &Q); |
|
return 1; |
|
} |
|
|
|
#ifdef ENABLE_MODULE_ECDH |
|
# include "modules/ecdh/main_impl.h" |
|
#endif |
|
|
|
#ifdef ENABLE_MODULE_RECOVERY |
|
# include "modules/recovery/main_impl.h" |
|
#endif
|
|
|