static int x509_info_ext_key_usage( char **buf, size_t *size,
                                    const mbedtls_x509_sequence *extended_key_usage )
{
    int ret;
    const char *desc;
    size_t n = *size;
    char *p = *buf;
    const mbedtls_x509_sequence *cur = extended_key_usage;
    const char *sep = "";

    while( cur != NULL )
    {
        if( mbedtls_oid_get_extended_key_usage( &cur->buf, &desc ) != 0 )
            desc = "???";

        ret = mbedtls_snprintf( p, n, "%s%s", sep, desc );
        MBEDTLS_X509_SAFE_SNPRINTF;

        sep = ", ";

        cur = cur->next;
    }

    *size = n;
    *buf = p;

    return( 0 );
}

When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.