Esempio n. 1
0
/*
 * Thread-safe wrapper for entropy_gather_internal()
 */
int mbedtls_entropy_gather( mbedtls_entropy_context *ctx )
{
    int ret;

#if defined(MBEDTLS_THREADING_C)
    if( ( ret = mbedtls_mutex_lock( &ctx->mutex ) ) != 0 )
        return( ret );
#endif

    ret = entropy_gather_internal( ctx );

#if defined(MBEDTLS_THREADING_C)
    if( mbedtls_mutex_unlock( &ctx->mutex ) != 0 )
        return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
#endif

    return( ret );
}
Esempio n. 2
0
/*
 * Thread-safe wrapper for entropy_gather_internal()
 */
int entropy_gather( entropy_context *ctx )
{
    int ret;

#if defined(POLARSSL_THREADING_C)
    if( ( ret = polarssl_mutex_lock( &ctx->mutex ) ) != 0 )
        return( ret );
#endif

    ret = entropy_gather_internal( ctx );

#if defined(POLARSSL_THREADING_C)
    if( polarssl_mutex_unlock( &ctx->mutex ) != 0 )
        return( POLARSSL_ERR_THREADING_MUTEX_ERROR );
#endif

    return( ret );
}
Esempio n. 3
0
int mbedtls_entropy_func( void *data, unsigned char *output, size_t len )
{
    int ret, count = 0, i, done;
    mbedtls_entropy_context *ctx = (mbedtls_entropy_context *) data;
    unsigned char buf[MBEDTLS_ENTROPY_BLOCK_SIZE];

    if( len > MBEDTLS_ENTROPY_BLOCK_SIZE )
        return( MBEDTLS_ERR_ENTROPY_SOURCE_FAILED );

#if defined(MBEDTLS_THREADING_C)
    if( ( ret = mbedtls_mutex_lock( &ctx->mutex ) ) != 0 )
        return( ret );
#endif

    /*
     * Always gather extra entropy before a call
     */
    do
    {
        if( count++ > ENTROPY_MAX_LOOP )
        {
            ret = MBEDTLS_ERR_ENTROPY_SOURCE_FAILED;
            goto exit;
        }

        if( ( ret = entropy_gather_internal( ctx ) ) != 0 )
            goto exit;

        done = 1;
        for( i = 0; i < ctx->source_count; i++ )
            if( ctx->source[i].size < ctx->source[i].threshold )
                done = 0;
    }
    while( ! done );

    memset( buf, 0, MBEDTLS_ENTROPY_BLOCK_SIZE );

#if defined(MBEDTLS_ENTROPY_SHA512_ACCUMULATOR)
    mbedtls_sha512_finish( &ctx->accumulator, buf );

    /*
     * Reset accumulator and counters and recycle existing entropy
     */
    memset( &ctx->accumulator, 0, sizeof( mbedtls_sha512_context ) );
    mbedtls_sha512_starts( &ctx->accumulator, 0 );
    mbedtls_sha512_update( &ctx->accumulator, buf, MBEDTLS_ENTROPY_BLOCK_SIZE );

    /*
     * Perform second SHA-512 on entropy
     */
    mbedtls_sha512( buf, MBEDTLS_ENTROPY_BLOCK_SIZE, buf, 0 );
#else /* MBEDTLS_ENTROPY_SHA512_ACCUMULATOR */
    mbedtls_sha256_finish( &ctx->accumulator, buf );

    /*
     * Reset accumulator and counters and recycle existing entropy
     */
    memset( &ctx->accumulator, 0, sizeof( mbedtls_sha256_context ) );
    mbedtls_sha256_starts( &ctx->accumulator, 0 );
    mbedtls_sha256_update( &ctx->accumulator, buf, MBEDTLS_ENTROPY_BLOCK_SIZE );

    /*
     * Perform second SHA-256 on entropy
     */
    mbedtls_sha256( buf, MBEDTLS_ENTROPY_BLOCK_SIZE, buf, 0 );
#endif /* MBEDTLS_ENTROPY_SHA512_ACCUMULATOR */

    for( i = 0; i < ctx->source_count; i++ )
        ctx->source[i].size = 0;

    memcpy( output, buf, len );

    ret = 0;

exit:
#if defined(MBEDTLS_THREADING_C)
    if( mbedtls_mutex_unlock( &ctx->mutex ) != 0 )
        return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
#endif

    return( ret );
}
Esempio n. 4
0
int entropy_func( void *data, unsigned char *output, size_t len )
{
    int ret, count = 0, i, reached;
    entropy_context *ctx = (entropy_context *) data;
    unsigned char buf[ENTROPY_BLOCK_SIZE];

    if( len > ENTROPY_BLOCK_SIZE )
        return( POLARSSL_ERR_ENTROPY_SOURCE_FAILED );

#if defined(POLARSSL_THREADING_C)
    if( ( ret = polarssl_mutex_lock( &ctx->mutex ) ) != 0 )
        return( ret );
#endif

    /*
     * Always gather extra entropy before a call
     */
    do
    {
        if( count++ > ENTROPY_MAX_LOOP )
        {
            ret = POLARSSL_ERR_ENTROPY_SOURCE_FAILED;
            goto exit;
        }

        if( ( ret = entropy_gather_internal( ctx ) ) != 0 )
            goto exit;

        reached = 0;

        for( i = 0; i < ctx->source_count; i++ )
            if( ctx->source[i].size >= ctx->source[i].threshold )
                reached++;
    }
    while( reached != ctx->source_count );

    memset( buf, 0, ENTROPY_BLOCK_SIZE );

#if defined(POLARSSL_ENTROPY_SHA512_ACCUMULATOR)
    sha512_finish( &ctx->accumulator, buf );

    /*
     * Reset accumulator and counters and recycle existing entropy
     */
    memset( &ctx->accumulator, 0, sizeof( sha512_context ) );
    sha512_starts( &ctx->accumulator, 0 );
    sha512_update( &ctx->accumulator, buf, ENTROPY_BLOCK_SIZE );

    /*
     * Perform second SHA-512 on entropy
     */
    sha512( buf, ENTROPY_BLOCK_SIZE, buf, 0 );
#else /* POLARSSL_ENTROPY_SHA512_ACCUMULATOR */
    sha256_finish( &ctx->accumulator, buf );

    /*
     * Reset accumulator and counters and recycle existing entropy
     */
    memset( &ctx->accumulator, 0, sizeof( sha256_context ) );
    sha256_starts( &ctx->accumulator, 0 );
    sha256_update( &ctx->accumulator, buf, ENTROPY_BLOCK_SIZE );

    /*
     * Perform second SHA-256 on entropy
     */
    sha256( buf, ENTROPY_BLOCK_SIZE, buf, 0 );
#endif /* POLARSSL_ENTROPY_SHA512_ACCUMULATOR */

    for( i = 0; i < ctx->source_count; i++ )
        ctx->source[i].size = 0;

    memcpy( output, buf, len );

    ret = 0;

exit:
#if defined(POLARSSL_THREADING_C)
    if( polarssl_mutex_unlock( &ctx->mutex ) != 0 )
        return( POLARSSL_ERR_THREADING_MUTEX_ERROR );
#endif

    return( ret );
}
Esempio n. 5
0
int mbedtls_entropy_func( void *data, unsigned char *output, size_t len )
{
    int ret, count = 0, i, done;
    mbedtls_entropy_context *ctx = (mbedtls_entropy_context *) data;
    unsigned char buf[MBEDTLS_ENTROPY_BLOCK_SIZE];

    if( len > MBEDTLS_ENTROPY_BLOCK_SIZE )
        return( MBEDTLS_ERR_ENTROPY_SOURCE_FAILED );

#if defined(MBEDTLS_ENTROPY_NV_SEED)
    /* Update the NV entropy seed before generating any entropy for outside
     * use.
     */
    if( ctx->initial_entropy_run == 0 )
    {
        ctx->initial_entropy_run = 1;
        if( ( ret = mbedtls_entropy_update_nv_seed( ctx ) ) != 0 )
            return( ret );
    }
#endif

#if defined(MBEDTLS_THREADING_C)
    if( ( ret = mbedtls_mutex_lock( &ctx->mutex ) ) != 0 )
        return( ret );
#endif

    /*
     * Always gather extra entropy before a call
     */
    do
    {
        if( count++ > ENTROPY_MAX_LOOP )
        {
            ret = MBEDTLS_ERR_ENTROPY_SOURCE_FAILED;
            goto exit;
        }

        if( ( ret = entropy_gather_internal( ctx ) ) != 0 )
            goto exit;

        done = 1;
        for( i = 0; i < ctx->source_count; i++ )
            if( ctx->source[i].size < ctx->source[i].threshold )
                done = 0;
    }
    while( ! done );

    memset( buf, 0, MBEDTLS_ENTROPY_BLOCK_SIZE );

#if defined(MBEDTLS_ENTROPY_SHA512_ACCUMULATOR)
    /*
     * Note that at this stage it is assumed that the accumulator was started
     * in a previous call to entropy_update(). If this is not guaranteed, the
     * code below will fail.
     */
    if( ( ret = mbedtls_sha512_finish_ret( &ctx->accumulator, buf ) ) != 0 )
        goto exit;

    /*
     * Reset accumulator and counters and recycle existing entropy
     */
    mbedtls_sha512_free( &ctx->accumulator );
    mbedtls_sha512_init( &ctx->accumulator );
    if( ( ret = mbedtls_sha512_starts_ret( &ctx->accumulator, 0 ) ) != 0 )
        goto exit;
    if( ( ret = mbedtls_sha512_update_ret( &ctx->accumulator, buf,
                                           MBEDTLS_ENTROPY_BLOCK_SIZE ) ) != 0 )
        goto exit;

    /*
     * Perform second SHA-512 on entropy
     */
    if( ( ret = mbedtls_sha512_ret( buf, MBEDTLS_ENTROPY_BLOCK_SIZE,
                                    buf, 0 ) ) != 0 )
        goto exit;
#else /* MBEDTLS_ENTROPY_SHA512_ACCUMULATOR */
    if( ( ret = mbedtls_sha256_finish_ret( &ctx->accumulator, buf ) ) != 0 )
        goto exit;

    /*
     * Reset accumulator and counters and recycle existing entropy
     */
    mbedtls_sha256_free( &ctx->accumulator );
    mbedtls_sha256_init( &ctx->accumulator );
    if( ( ret = mbedtls_sha256_starts_ret( &ctx->accumulator, 0 ) ) != 0 )
        goto exit;
    if( ( ret = mbedtls_sha256_update_ret( &ctx->accumulator, buf,
                                           MBEDTLS_ENTROPY_BLOCK_SIZE ) ) != 0 )
        goto exit;

    /*
     * Perform second SHA-256 on entropy
     */
    if( ( ret = mbedtls_sha256_ret( buf, MBEDTLS_ENTROPY_BLOCK_SIZE,
                                    buf, 0 ) ) != 0 )
        goto exit;
#endif /* MBEDTLS_ENTROPY_SHA512_ACCUMULATOR */

    for( i = 0; i < ctx->source_count; i++ )
        ctx->source[i].size = 0;

    memcpy( output, buf, len );

    ret = 0;

exit:
    mbedtls_zeroize( buf, sizeof( buf ) );

#if defined(MBEDTLS_THREADING_C)
    if( mbedtls_mutex_unlock( &ctx->mutex ) != 0 )
        return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
#endif

    return( ret );
}