bool ECDSA_Sign(COSE * pSigner, int index, const cn_cbor * pKey, int cbitDigest, const byte * rgbToSign, size_t cbToSign, cose_errback * perr)
{
EC_KEY * eckey = NULL;
byte rgbDigest[EVP_MAX_MD_SIZE];
unsigned int cbDigest = sizeof(rgbDigest);
byte * pbSig = NULL;
const EVP_MD * digest;
#ifdef USE_CBOR_CONTEXT
cn_cbor_context * context = &pSigner->m_allocContext;
#endif
cn_cbor * p = NULL;
ECDSA_SIG * psig = NULL;
cn_cbor_errback cbor_error;
int cbR;
byte rgbSig[66];
int cb;
eckey = ECKey_From(pKey, &cbR, perr);
if (eckey == NULL) {
errorReturn:
if (p != NULL) CN_CBOR_FREE(p, context);
if (eckey != NULL) EC_KEY_free(eckey);
return false;
}
switch (cbitDigest) {
case 256: digest = EVP_sha256(); break;
case 512: digest = EVP_sha512(); break;
case 384: digest = EVP_sha384(); break;
default:
FAIL_CONDITION(COSE_ERR_INVALID_PARAMETER);
}
EVP_Digest(rgbToSign, cbToSign, rgbDigest, &cbDigest, digest, NULL);
psig = ECDSA_do_sign(rgbDigest, cbDigest, eckey);
CHECK_CONDITION(psig != NULL, COSE_ERR_CRYPTO_FAIL);
pbSig = COSE_CALLOC(cbR, 2, context);
CHECK_CONDITION(pbSig != NULL, COSE_ERR_OUT_OF_MEMORY);
cb = BN_bn2bin(psig->r, rgbSig);
CHECK_CONDITION(cb <= cbR, COSE_ERR_INVALID_PARAMETER);
memcpy(pbSig + cbR - cb, rgbSig, cb);
cb = BN_bn2bin(psig->s, rgbSig);
CHECK_CONDITION(cb <= cbR, COSE_ERR_INVALID_PARAMETER);
memcpy(pbSig + 2*cbR - cb, rgbSig, cb);
p = cn_cbor_data_create(pbSig, cbR*2, CBOR_CONTEXT_PARAM_COMMA &cbor_error);
CHECK_CONDITION_CBOR(p != NULL, cbor_error);
CHECK_CONDITION(_COSE_array_replace(pSigner, p, index, CBOR_CONTEXT_PARAM_COMMA NULL), COSE_ERR_CBOR);
return true;
}
bool ECDSA_Verify(COSE * pSigner, int index, const cn_cbor * pKey, int cbitDigest, const byte * rgbToSign, size_t cbToSign, cose_errback * perr)
{
mbedtls_ecp_keypair keypair;
mbedtls_mpi r;
mbedtls_mpi s;
mbedtls_md_type_t mdType;
const mbedtls_md_info_t *pmdInfo;
byte rgbDigest[MBEDTLS_MD_MAX_SIZE];
cn_cbor * pSig;
bool result = false;
mbedtls_ecp_keypair_init(&keypair);
mbedtls_mpi_init(&r);
mbedtls_mpi_init(&s);
if(!ECKey_From(pKey, &keypair, perr)) goto errorReturn;
switch(cbitDigest)
{
case 256:
mdType = MBEDTLS_MD_SHA256;
break;
case 384:
mdType = MBEDTLS_MD_SHA384;
break;
case 512:
mdType = MBEDTLS_MD_SHA512;
break;
default:
FAIL_CONDITION(COSE_ERR_INVALID_PARAMETER);
}
pmdInfo = mbedtls_md_info_from_type(mdType);
CHECK_CONDITION(pmdInfo != NULL, COSE_ERR_INVALID_PARAMETER);
CHECK_CONDITION(mbedtls_md(pmdInfo, rgbToSign, cbToSign, rgbDigest) == 0, COSE_ERR_INVALID_PARAMETER);
pSig = _COSE_arrayget_int(pSigner, index);
CHECK_CONDITION((pSig != NULL) && (pSig->type == CN_CBOR_BYTES), COSE_ERR_INVALID_PARAMETER);
CHECK_CONDITION(mbedtls_mpi_read_binary( &r, pSig->v.bytes, pSig->length / 2 ) == 0, COSE_ERR_OUT_OF_MEMORY);
CHECK_CONDITION(mbedtls_mpi_read_binary( &s, pSig->v.bytes + pSig->length / 2, pSig->length / 2 ) == 0, COSE_ERR_OUT_OF_MEMORY);
CHECK_CONDITION(mbedtls_ecdsa_verify(&keypair.grp, rgbDigest, mbedtls_md_get_size(pmdInfo), &keypair.Q, &r, &s) == 0, COSE_ERR_CRYPTO_FAIL);
result = true;
errorReturn:
mbedtls_mpi_free(&r);
mbedtls_mpi_free(&s);
mbedtls_ecp_keypair_free(&keypair);
return result;
}
bool ECDSA_Verify(COSE * pSigner, int index, const cn_cbor * pKey, int cbitDigest, const byte * rgbToSign, size_t cbToSign, cose_errback * perr)
{
EC_KEY * eckey = NULL;
byte rgbDigest[EVP_MAX_MD_SIZE];
unsigned int cbDigest = sizeof(rgbDigest);
const EVP_MD * digest;
#ifdef USE_CBOR_CONTEXT
cn_cbor_context * context = &pSigner->m_allocContext;
#endif
cn_cbor * p = NULL;
ECDSA_SIG sig = { NULL, NULL };
int cbR;
cn_cbor * pSig;
size_t cbSignature;
eckey = ECKey_From(pKey, &cbR, perr);
if (eckey == NULL) {
errorReturn:
if (sig.r != NULL) BN_free(sig.r);
if (sig.s != NULL) BN_free(sig.s);
if (p != NULL) CN_CBOR_FREE(p, context);
if (eckey != NULL) EC_KEY_free(eckey);
return false;
}
switch (cbitDigest) {
case 256: digest = EVP_sha256(); break;
case 512: digest = EVP_sha512(); break;
case 384: digest = EVP_sha384(); break;
default:
FAIL_CONDITION(COSE_ERR_INVALID_PARAMETER);
}
EVP_Digest(rgbToSign, cbToSign, rgbDigest, &cbDigest, digest, NULL);
pSig = _COSE_arrayget_int(pSigner, index);
CHECK_CONDITION(pSig != NULL, CN_CBOR_ERR_INVALID_PARAMETER);
cbSignature = pSig->length;
CHECK_CONDITION(cbSignature / 2 == cbR, COSE_ERR_INVALID_PARAMETER);
sig.r = BN_bin2bn(pSig->v.bytes,(int) cbSignature/2, NULL);
sig.s = BN_bin2bn(pSig->v.bytes+cbSignature/2, (int) cbSignature/2, NULL);
CHECK_CONDITION(ECDSA_do_verify(rgbDigest, cbDigest, &sig, eckey) == 1, COSE_ERR_CRYPTO_FAIL);
BN_free(sig.r);
BN_free(sig.s);
if (eckey != NULL) EC_KEY_free(eckey);
return true;
}
bool ECDSA_Sign(COSE * pSigner, int index, const cn_cbor * pKey, int cbitDigest, const byte * rgbToSign, size_t cbToSign, cose_errback * perr)
{
#if defined(MBEDTLS_ECDSA_DETERMINISTIC)
byte rgbDigest[MBEDTLS_MD_MAX_SIZE];
uint8_t * pbSig = NULL;
cn_cbor_errback cbor_error;
int cbR;
mbedtls_md_type_t mdType;
const mbedtls_md_info_t *pmdInfo;
mbedtls_ecp_keypair keypair;
mbedtls_mpi r;
mbedtls_mpi s;
#ifdef USE_CBOR_CONTEXT
cn_cbor_context * context = &pSigner->m_allocContext;
#endif
cn_cbor * p = NULL;
bool result = false;
mbedtls_ecp_keypair_init(&keypair);
mbedtls_mpi_init(&r);
mbedtls_mpi_init(&s);
if(!ECKey_From(pKey, &keypair, perr)) goto errorReturn;
CHECK_CONDITION(keypair.d.n != 0, COSE_ERR_INVALID_PARAMETER);
switch(cbitDigest)
{
case 256:
mdType = MBEDTLS_MD_SHA256;
break;
case 384:
mdType = MBEDTLS_MD_SHA384;
break;
case 512:
mdType = MBEDTLS_MD_SHA512;
break;
default:
FAIL_CONDITION(COSE_ERR_INVALID_PARAMETER);
}
pmdInfo = mbedtls_md_info_from_type(mdType);
CHECK_CONDITION(pmdInfo != NULL, COSE_ERR_INVALID_PARAMETER);
CHECK_CONDITION(mbedtls_md(pmdInfo, rgbToSign, cbToSign, rgbDigest) == 0, COSE_ERR_INVALID_PARAMETER);
CHECK_CONDITION(mbedtls_ecdsa_sign_det(&keypair.grp, &r, &s, &keypair.d, rgbDigest, mbedtls_md_get_size(pmdInfo), mdType) == 0, COSE_ERR_CRYPTO_FAIL);
cbR = (keypair.grp.nbits + 7) / 8;
pbSig = COSE_CALLOC(cbR, 2, context);
CHECK_CONDITION(pbSig != NULL, COSE_ERR_OUT_OF_MEMORY);
CHECK_CONDITION(mbedtls_mpi_write_binary(&r, pbSig, cbR) == 0, COSE_ERR_INTERNAL);
CHECK_CONDITION(mbedtls_mpi_write_binary(&s, pbSig + cbR, cbR) == 0, COSE_ERR_INTERNAL);
p = cn_cbor_data_create(pbSig, cbR*2, CBOR_CONTEXT_PARAM_COMMA &cbor_error);
CHECK_CONDITION_CBOR(p != NULL, cbor_error);
CHECK_CONDITION(_COSE_array_replace(pSigner, p, index, CBOR_CONTEXT_PARAM_COMMA NULL), COSE_ERR_CBOR);
p = NULL;
pbSig = NULL;
result = true;
errorReturn:
cn_cbor_free(p CBOR_CONTEXT_PARAM);
COSE_FREE(pbSig, context);
mbedtls_mpi_free(&r);
mbedtls_mpi_free(&s);
mbedtls_ecp_keypair_free(&keypair);
return result;
#else
return false;
#endif
}
