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Add a minimal example for ecc verify
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ecc/ecc-verify-minimal.c

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/* ecc-verify-minimal.c
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*
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* Copyright (C) 2006-2026 wolfSSL Inc.
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*
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* This file is part of wolfSSL.
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*
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* wolfSSL is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* wolfSSL is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1335, USA
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*/
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#include <wolfssl/options.h>
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#include <wolfssl/wolfcrypt/settings.h>
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#include <wolfssl/wolfcrypt/ecc.h>
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#include <stdio.h>
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#include <string.h>
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static const byte signedMessageSha256Hash[32] = {
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0xa5, 0xa5, 0xa5, 0xa5, 0xa5, 0xa5, 0xa5, 0xa5, 0xa5, 0xa5, 0xa5, 0xa5,
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0xa5, 0xa5, 0xa5, 0xa5, 0xa5, 0xa5, 0xa5, 0xa5, 0xa5, 0xa5, 0xa5, 0xa5,
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0xa5, 0xa5, 0xa5, 0xa5, 0xa5, 0xa5, 0xa5, 0xa5
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};
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static const byte ecdsaSignatureDer[72] = {
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0x30, 0x46, 0x02, 0x21, 0x00, 0xd9, 0x8a, 0xe0, 0xea, 0xcf, 0xae, 0x30,
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0x70, 0xd1, 0x9c, 0xdd, 0x0d, 0xd0, 0x77, 0x73, 0x77, 0x87, 0xb6, 0x2a,
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0x99, 0xe5, 0x41, 0x91, 0x29, 0xda, 0xff, 0x5e, 0x95, 0xe8, 0xec, 0xf9,
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0x9a, 0x02, 0x21, 0x00, 0xa6, 0x71, 0x98, 0xed, 0x9b, 0x82, 0xa0, 0xba,
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0x60, 0xc5, 0xd2, 0x56, 0xae, 0x68, 0xb2, 0xd3, 0x29, 0x56, 0x88, 0xe8,
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0x47, 0xd5, 0xf1, 0x91, 0x0b, 0xac, 0xe4, 0xe9, 0x00, 0xf8, 0x31, 0x4c
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};
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/* X9.63 uncompressed public key (0x04 || X || Y) */
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static const byte signerPublicKey[65] = {
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0x04, 0xf6, 0x7f, 0x27, 0xc2, 0xa3, 0xeb, 0x3b, 0x4f, 0xc9, 0xec, 0xdb,
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0x64, 0x72, 0xe7, 0x16, 0x51, 0xc3, 0xfb, 0xdd, 0x5c, 0xe0, 0x82, 0xc6,
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0x0c, 0x9e, 0x62, 0x6a, 0x34, 0xfc, 0x47, 0xcb, 0xe6, 0x1a, 0x08, 0x7c,
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0x44, 0x54, 0x88, 0x69, 0xb4, 0x6f, 0x5d, 0x93, 0xde, 0xdc, 0x4e, 0x7f,
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0x1a, 0xb7, 0x75, 0xe2, 0xfd, 0x5f, 0xd6, 0x7d, 0x6a, 0xd3, 0x00, 0x2c,
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0x09, 0x99, 0xaf, 0x2f, 0x0f
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};
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int main(void)
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{
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int ret, is_valid_sig = 0;
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ecc_key key;
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/* Initialize the ecc_key structure before use. */
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if ((ret = wc_ecc_init(&key)) != 0) {
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printf("wc_ecc_init failed: %d\n", ret);
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return ret;
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}
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/* Load the signer's public key in X9.63 uncompressed form. */
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ret = wc_ecc_import_x963_ex(signerPublicKey, sizeof(signerPublicKey),
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&key, ECC_SECP256R1);
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if (ret != 0) {
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printf("wc_ecc_import_x963_ex failed: %d\n", ret);
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goto cleanup;
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}
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/* Reject short digests to guard against the short-hash bypass CVE. */
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if (sizeof(signedMessageSha256Hash) < WC_MIN_DIGEST_SIZE) {
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goto cleanup;
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}
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/* Verify the ECDSA signature over the precomputed hash. */
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ret = wc_ecc_verify_hash(ecdsaSignatureDer, sizeof(ecdsaSignatureDer),
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signedMessageSha256Hash, sizeof(signedMessageSha256Hash),
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&is_valid_sig, &key);
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printf("wc_ecc_verify_hash: ret=%d, is_valid_sig=%d\n", ret, is_valid_sig);
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cleanup:
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wc_ecc_free(&key);
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return ret;
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}

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