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Diffstat (limited to 'crypto/secp256k1/ext.h')
| -rw-r--r-- | crypto/secp256k1/ext.h | 130 |
1 files changed, 0 insertions, 130 deletions
diff --git a/crypto/secp256k1/ext.h b/crypto/secp256k1/ext.h deleted file mode 100644 index e422fe4b4..000000000 --- a/crypto/secp256k1/ext.h +++ /dev/null @@ -1,130 +0,0 @@ -// Copyright 2015 Jeffrey Wilcke, Felix Lange, Gustav Simonsson. All rights reserved. -// Use of this source code is governed by a BSD-style license that can be found in -// the LICENSE file. - -// secp256k1_context_create_sign_verify creates a context for signing and signature verification. -static secp256k1_context* secp256k1_context_create_sign_verify() { - return secp256k1_context_create(SECP256K1_CONTEXT_SIGN | SECP256K1_CONTEXT_VERIFY); -} - -// secp256k1_ext_ecdsa_recover recovers the public key of an encoded compact signature. -// -// Returns: 1: recovery was successful -// 0: recovery was not successful -// Args: ctx: pointer to a context object (cannot be NULL) -// Out: pubkey_out: the serialized 65-byte public key of the signer (cannot be NULL) -// In: sigdata: pointer to a 65-byte signature with the recovery id at the end (cannot be NULL) -// msgdata: pointer to a 32-byte message (cannot be NULL) -static int secp256k1_ext_ecdsa_recover( - const secp256k1_context* ctx, - unsigned char *pubkey_out, - const unsigned char *sigdata, - const unsigned char *msgdata -) { - secp256k1_ecdsa_recoverable_signature sig; - secp256k1_pubkey pubkey; - - if (!secp256k1_ecdsa_recoverable_signature_parse_compact(ctx, &sig, sigdata, (int)sigdata[64])) { - return 0; - } - if (!secp256k1_ecdsa_recover(ctx, &pubkey, &sig, msgdata)) { - return 0; - } - size_t outputlen = 65; - return secp256k1_ec_pubkey_serialize(ctx, pubkey_out, &outputlen, &pubkey, SECP256K1_EC_UNCOMPRESSED); -} - -// secp256k1_ext_ecdsa_verify verifies an encoded compact signature. -// -// Returns: 1: signature is valid -// 0: signature is invalid -// Args: ctx: pointer to a context object (cannot be NULL) -// In: sigdata: pointer to a 64-byte signature (cannot be NULL) -// msgdata: pointer to a 32-byte message (cannot be NULL) -// pubkeydata: pointer to public key data (cannot be NULL) -// pubkeylen: length of pubkeydata -static int secp256k1_ext_ecdsa_verify( - const secp256k1_context* ctx, - const unsigned char *sigdata, - const unsigned char *msgdata, - const unsigned char *pubkeydata, - size_t pubkeylen -) { - secp256k1_ecdsa_signature sig; - secp256k1_pubkey pubkey; - - if (!secp256k1_ecdsa_signature_parse_compact(ctx, &sig, sigdata)) { - return 0; - } - if (!secp256k1_ec_pubkey_parse(ctx, &pubkey, pubkeydata, pubkeylen)) { - return 0; - } - return secp256k1_ecdsa_verify(ctx, &sig, msgdata, &pubkey); -} - -// secp256k1_ext_reencode_pubkey decodes then encodes a public key. It can be used to -// convert between public key formats. The input/output formats are chosen depending on the -// length of the input/output buffers. -// -// Returns: 1: conversion successful -// 0: conversion unsuccessful -// Args: ctx: pointer to a context object (cannot be NULL) -// Out: out: output buffer that will contain the reencoded key (cannot be NULL) -// In: outlen: length of out (33 for compressed keys, 65 for uncompressed keys) -// pubkeydata: the input public key (cannot be NULL) -// pubkeylen: length of pubkeydata -static int secp256k1_ext_reencode_pubkey( - const secp256k1_context* ctx, - unsigned char *out, - size_t outlen, - const unsigned char *pubkeydata, - size_t pubkeylen -) { - secp256k1_pubkey pubkey; - - if (!secp256k1_ec_pubkey_parse(ctx, &pubkey, pubkeydata, pubkeylen)) { - return 0; - } - unsigned int flag = (outlen == 33) ? SECP256K1_EC_COMPRESSED : SECP256K1_EC_UNCOMPRESSED; - return secp256k1_ec_pubkey_serialize(ctx, out, &outlen, &pubkey, flag); -} - -// secp256k1_ext_scalar_mul multiplies a point by a scalar in constant time. -// -// Returns: 1: multiplication was successful -// 0: scalar was invalid (zero or overflow) -// Args: ctx: pointer to a context object (cannot be NULL) -// Out: point: the multiplied point (usually secret) -// In: point: pointer to a 64-byte public point, -// encoded as two 256bit big-endian numbers. -// scalar: a 32-byte scalar with which to multiply the point -int secp256k1_ext_scalar_mul(const secp256k1_context* ctx, unsigned char *point, const unsigned char *scalar) { - int ret = 0; - int overflow = 0; - secp256k1_fe feX, feY; - secp256k1_gej res; - secp256k1_ge ge; - secp256k1_scalar s; - ARG_CHECK(point != NULL); - ARG_CHECK(scalar != NULL); - (void)ctx; - - secp256k1_fe_set_b32(&feX, point); - secp256k1_fe_set_b32(&feY, point+32); - secp256k1_ge_set_xy(&ge, &feX, &feY); - secp256k1_scalar_set_b32(&s, scalar, &overflow); - if (overflow || secp256k1_scalar_is_zero(&s)) { - ret = 0; - } else { - secp256k1_ecmult_const(&res, &ge, &s); - secp256k1_ge_set_gej(&ge, &res); - /* Note: can't use secp256k1_pubkey_save here because it is not constant time. */ - secp256k1_fe_normalize(&ge.x); - secp256k1_fe_normalize(&ge.y); - secp256k1_fe_get_b32(point, &ge.x); - secp256k1_fe_get_b32(point+32, &ge.y); - ret = 1; - } - secp256k1_scalar_clear(&s); - return ret; -} |