[LTP] [PATCH v3 27/36] keyctl31: Test KEYCTL_PKEY_ENCRYPT and KEYCTL_PKEY_DECRYPT

[Cyril Hrubis]

Hi!
> diff --git a/testcases/kernel/syscalls/keyctl/keyctl31.c b/testcases/kernel/syscalls/keyctl/keyctl31.c
> new file mode 100644
> index 0000000000..c1e6723ac8
> --- /dev/null
> +++ b/testcases/kernel/syscalls/keyctl/keyctl31.c
> @@ -0,0 +1,110 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + * Copyright (c) 2026 Andrea Cervesato <andrea.cervesato@suse.com>
> + */
> +
> +/*\
> + * Test ``KEYCTL_PKEY_ENCRYPT`` and ``KEYCTL_PKEY_DECRYPT`` of :manpage:`keyctl(2)`.
> + *
> + * ``KEYCTL_PKEY_ENCRYPT`` encrypts a data blob using an asymmetric public key
> + * and ``KEYCTL_PKEY_DECRYPT`` decrypts the encrypted blob using the matching
> + * private key.
> + *
> + * Requires root (CAP_SYS_MODULE) to load the ``x509_key_parser`` and
> + * ``pkcs8_key_parser`` modules.
> + *
> + * [Algorithm]
> + *
> + * - encrypt a 32-byte plaintext using an RSA-2048 X.509 public key with ``enc=pkcs1``
> + * - decrypt the 256-byte ciphertext using the matching PKCS#8 private key
> + * - verify the decrypted output matches the original 32-byte plaintext
> + */
> +
> +#include "keyctl_common.h"
> +#include "keyctl_pkey_data.h"
> +#include "tst_module.h"
> +
> +#define CIPHERTEXT_SIZE	256
> +
> +static const char plaintext[] = "LTP_PKEY_ENCRYPT_DECRYPT_TEST_32";
> +#define PLAINTEXT_SIZE	(sizeof(plaintext) - 1)
> +static unsigned char ciphertext[CIPHERTEXT_SIZE];
> +static unsigned char decrypted[CIPHERTEXT_SIZE];

Shouldn't these two be in the guarded buffers as well? I would say that
it's pretty much important that the kernel does not touch anything
outside of these arrays during encryption/decryption.

Otherwise:

Reviewed-by: Cyril Hrubis <chrubis@suse.cz>

-- 
Cyril Hrubis
chrubis@suse.cz