/* BEGIN_HEADER */
#include "mbedtls/chacha20.h"
/* END_HEADER */

/* BEGIN_DEPENDENCIES
 * depends_on:MBEDTLS_CHACHA20_C
 * END_DEPENDENCIES
 */

/* BEGIN_CASE */
void chacha20_crypt( data_t *key_str,
                     data_t *nonce_str,
                     int counter,
                     data_t *src_str,
                     data_t *expected_output_str )
{
    unsigned char output[375];
    mbedtls_chacha20_context ctx;

    memset( output, 0x00, sizeof( output ) );

    TEST_ASSERT( src_str->len   == expected_output_str->len );
    TEST_ASSERT( key_str->len   == 32U );
    TEST_ASSERT( nonce_str->len == 12U );

    /*
     * Test the integrated API
     */
    TEST_ASSERT( mbedtls_chacha20_crypt( key_str->x, nonce_str->x, counter, src_str->len, src_str->x, output ) == 0 );

    ASSERT_COMPARE( output, expected_output_str->len,
                    expected_output_str->x, expected_output_str->len );

    /*
     * Test the streaming API
     */
    mbedtls_chacha20_init( &ctx );

    TEST_ASSERT( mbedtls_chacha20_setkey( &ctx, key_str->x ) == 0 );

    TEST_ASSERT( mbedtls_chacha20_starts( &ctx, nonce_str->x, counter ) == 0 );

    memset( output, 0x00, sizeof( output ) );
    TEST_ASSERT( mbedtls_chacha20_update( &ctx, src_str->len, src_str->x, output ) == 0 );

    ASSERT_COMPARE( output, expected_output_str->len,
                    expected_output_str->x, expected_output_str->len );

    /*
     * Test the streaming API again, piecewise
     */

    /* Don't free/init the context nor set the key again,
     * in order to test that starts() does the right thing. */
    TEST_ASSERT( mbedtls_chacha20_starts( &ctx, nonce_str->x, counter ) == 0 );

    memset( output, 0x00, sizeof( output ) );
    TEST_ASSERT( mbedtls_chacha20_update( &ctx, 1, src_str->x, output ) == 0 );
    TEST_ASSERT( mbedtls_chacha20_update( &ctx, src_str->len - 1,
                                          src_str->x + 1, output + 1 ) == 0 );

    ASSERT_COMPARE( output, expected_output_str->len,
                    expected_output_str->x, expected_output_str->len );

    mbedtls_chacha20_free( &ctx );
}
/* END_CASE */

/* BEGIN_CASE depends_on:MBEDTLS_SELF_TEST */
void chacha20_self_test()
{
    TEST_ASSERT( mbedtls_chacha20_self_test( 1 ) == 0 );
}
/* END_CASE */