[tarantool-patches] Re: [PATCH 1/1] test: fix unit/crypto test flakiness

[Vladislav Shpilevoy <v.shpilevoy@tarantool.org>]

Pushed to the master.

On 23/06/2019 20:17, Vladislav Shpilevoy wrote:
> One of subtests was checking if crypto_decode returns an error
> when fails to decode. But due to randomness of the test sometimes
> it happened, that initial vector of encrypted data somehow didn't
> lead to an error. Decryption was not correct, but only in terms
> of result, not in terms of decryption algorithm. -1 was not
> returned, and diag was not set.
> 
> This patch checks all the cases.
> 
> Closes #4306
> ---
> Branch: https://github.com/tarantool/tarantool/tree/gerold103/gh-4306-flaky-unit-crypto
> Issue: https://github.com/tarantool/tarantool/issues/4306
> 
> [CC += Georgy] because he is an author of crypto module.
> [CC += Alexander] because he is an author of the issue, and revolves around
> tests.
> 
>  test/unit/crypto.c      | 16 +++++++++++-----
>  test/unit/crypto.result |  4 ++--
>  2 files changed, 13 insertions(+), 7 deletions(-)
> 
> diff --git a/test/unit/crypto.c b/test/unit/crypto.c
> index fad1842f1..8dc4c7332 100644
> --- a/test/unit/crypto.c
> +++ b/test/unit/crypto.c
> @@ -86,11 +86,17 @@ test_aes128_codec(void)
>  	is(rc, plain_size, "decrypt returns correct number of bytes");
>  	is(memcmp(buffer2, plain, plain_size), 0,
>  	   "and correctly decrypts data");
> -
> -	rc = crypto_codec_decrypt(c, "false iv not meaning anything",
> -				  buffer1, 16, buffer2, buffer_size);
> -	is(rc, -1, "decrypt can fail with wrong IV");
> -	ok(! diag_is_empty(diag_get()), "diag error is set");
> +	/*
> +	 * Create a different IV to ensure it does not decrypt a
> +	 * message with the original IV.
> +	 */
> +	for (int i = 0; i < CRYPTO_AES_IV_SIZE; ++i)
> +		iv[i]++;
> +	rc = crypto_codec_decrypt(c, iv, buffer1, 16, buffer2, buffer_size);
> +	ok(rc == -1 || rc != plain_size || memcmp(buffer1, buffer2, rc) != 0,
> +	   "decrypt can't correctly decode anything with a wrong IV");
> +	ok(rc != -1 || ! diag_is_empty(diag_get()),
> +	   "in case decrypt has totally failed, diag is set");
>  
>  	crypto_codec_gen_iv(c, iv2, sizeof(iv2));
>  	rc = crypto_codec_encrypt(c, iv2, plain, plain_size,
> diff --git a/test/unit/crypto.result b/test/unit/crypto.result
> index d6ff327e6..6e01896b1 100644
> --- a/test/unit/crypto.result
> +++ b/test/unit/crypto.result
> @@ -15,8 +15,8 @@ ok 1 - crypto checks that algo argument is correct
>      ok 10 - decrypt also checks length and returns needed number of bytes
>      ok 11 - decrypt returns correct number of bytes
>      ok 12 - and correctly decrypts data
> -    ok 13 - decrypt can fail with wrong IV
> -    ok 14 - diag error is set
> +    ok 13 - decrypt can't correctly decode anything with a wrong IV
> +    ok 14 - in case decrypt has totally failed, diag is set
>      ok 15 - encrypt with different IV and the same number of written bytes returned
>      ok 16 - the encrypted data looks different
>      ok 17 - decrypt works with correct but another IV
>