#include "ecdsa.hpp"
#include <mbedtls/ctr_drbg.h>
#include <mbedtls/ecdsa.h>
#include <mbedtls/pk.h>
#include "common/code_utils.hpp"
#include "common/debug.hpp"
#include "common/random.hpp"
namespace ot {
namespace Crypto {
#if OPENTHREAD_CONFIG_ECDSA_ENABLE
otError Ecdsa::Sign(uint8_t * aOutput,
uint16_t & aOutputLength,
const uint8_t *aInputHash,
uint16_t aInputHashLength,
const uint8_t *aPrivateKey,
uint16_t aPrivateKeyLength)
{
otError error = OT_ERROR_NONE;
mbedtls_ecdsa_context ctx;
mbedtls_pk_context pkCtx;
mbedtls_ecp_keypair * keypair;
mbedtls_mpi rMpi;
mbedtls_mpi sMpi;
mbedtls_pk_init(&pkCtx);
mbedtls_ecdsa_init(&ctx);
mbedtls_mpi_init(&rMpi);
mbedtls_mpi_init(&sMpi);
VerifyOrExit(mbedtls_pk_parse_key(&pkCtx, aPrivateKey, aPrivateKeyLength, NULL, 0) == 0,
error = OT_ERROR_INVALID_ARGS);
VerifyOrExit(mbedtls_pk_get_type(&pkCtx) == MBEDTLS_PK_ECKEY, error = OT_ERROR_INVALID_ARGS);
keypair = mbedtls_pk_ec(pkCtx);
OT_ASSERT(keypair != NULL);
VerifyOrExit(mbedtls_ecdsa_from_keypair(&ctx, keypair) == 0, error = OT_ERROR_FAILED);
VerifyOrExit(mbedtls_ecdsa_sign(&ctx.grp, &rMpi, &sMpi, &ctx.d, aInputHash, aInputHashLength,
mbedtls_ctr_drbg_random, Random::Crypto::MbedTlsContextGet()) == 0,
error = OT_ERROR_FAILED);
VerifyOrExit(mbedtls_mpi_size(&rMpi) + mbedtls_mpi_size(&sMpi) <= aOutputLength, error = OT_ERROR_NO_BUFS);
VerifyOrExit(mbedtls_mpi_write_binary(&rMpi, aOutput, mbedtls_mpi_size(&rMpi)) == 0, error = OT_ERROR_FAILED);
aOutputLength = static_cast<uint16_t>(mbedtls_mpi_size(&rMpi));
VerifyOrExit(mbedtls_mpi_write_binary(&sMpi, aOutput + aOutputLength, mbedtls_mpi_size(&sMpi)) == 0,
error = OT_ERROR_FAILED);
aOutputLength += mbedtls_mpi_size(&sMpi);
exit:
mbedtls_mpi_free(&rMpi);
mbedtls_mpi_free(&sMpi);
mbedtls_ecdsa_free(&ctx);
mbedtls_pk_free(&pkCtx);
return error;
}
#endif
} }