pk_ecc.c | Explore in Territory

/*
 *  ECC setters for PK.
 *
 *  Copyright The Mbed TLS Contributors
 *  SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
 */

#include "common.h"

#include "mbedtls/pk.h"
#include "mbedtls/error.h"
#include "mbedtls/ecp.h"
#include "pk_internal.h"

#if defined(MBEDTLS_PK_C) && defined(MBEDTLS_PK_HAVE_ECC_KEYS)

int mbedtls_pk_ecc_set_group(mbedtls_pk_context *pk, mbedtls_ecp_group_id grp_id)
{ … }

int mbedtls_pk_ecc_set_key(mbedtls_pk_context *pk, unsigned char *key, size_t key_len)
{ … }

int mbedtls_pk_ecc_set_pubkey_from_prv(mbedtls_pk_context *pk,
                                       const unsigned char *prv, size_t prv_len,
                                       int (*f_rng)(void *, unsigned char *, size_t), void *p_rng)
{ … }

#if defined(MBEDTLS_PK_USE_PSA_EC_DATA)
/*
 * Set the public key: fallback using ECP_LIGHT in the USE_PSA_EC_DATA case.
 *
 * Normally, when MBEDTLS_PK_USE_PSA_EC_DATA is enabled, we only use PSA
 * functions to handle keys. However, currently psa_import_key() does not
 * support compressed points. In case that support was explicitly requested,
 * this fallback uses ECP functions to get the job done. This is the reason
 * why MBEDTLS_PK_PARSE_EC_COMPRESSED auto-enables MBEDTLS_ECP_LIGHT.
 *
 * [in/out] pk: in: must have the group set, see mbedtls_pk_ecc_set_group().
 *              out: will have the public key set.
 * [in] pub, pub_len: the public key as an ECPoint,
 *                    in any format supported by ECP.
 *
 * Return:
 * - 0 on success;
 * - MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE if the format is potentially valid
 *   but not supported;
 * - another error code otherwise.
 */
static int pk_ecc_set_pubkey_psa_ecp_fallback(mbedtls_pk_context *pk,
                                              const unsigned char *pub,
                                              size_t pub_len)
{
#if !defined(MBEDTLS_PK_PARSE_EC_COMPRESSED)
    (void) pk;
    (void) pub;
    (void) pub_len;
    return MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE;
#else /* MBEDTLS_PK_PARSE_EC_COMPRESSED */
    mbedtls_ecp_keypair ecp_key;
    mbedtls_ecp_group_id ecp_group_id;
    int ret;

    ecp_group_id = mbedtls_ecc_group_from_psa(pk->ec_family, pk->ec_bits);

    mbedtls_ecp_keypair_init(&ecp_key);
    ret = mbedtls_ecp_group_load(&(ecp_key.grp), ecp_group_id);
    if (ret != 0) {
        goto exit;
    }
    ret = mbedtls_ecp_point_read_binary(&(ecp_key.grp), &ecp_key.Q,
                                        pub, pub_len);
    if (ret != 0) {
        goto exit;
    }
    ret = mbedtls_ecp_point_write_binary(&(ecp_key.grp), &ecp_key.Q,
                                         MBEDTLS_ECP_PF_UNCOMPRESSED,
                                         &pk->pub_raw_len, pk->pub_raw,
                                         sizeof(pk->pub_raw));

exit:
    mbedtls_ecp_keypair_free(&ecp_key);
    return ret;
#endif /* MBEDTLS_PK_PARSE_EC_COMPRESSED */
}
#endif /* MBEDTLS_PK_USE_PSA_EC_DATA */

int mbedtls_pk_ecc_set_pubkey(mbedtls_pk_context *pk, const unsigned char *pub, size_t pub_len)
{ … }

#endif /* MBEDTLS_PK_C && MBEDTLS_PK_HAVE_ECC_KEYS */
godot/thirdparty/mbedtls/library/pk_ecc.c
