TLS 1.3: ServerHello: add utils functions used by ServerHello
Regarding the merge job, there was only one of the failure we currently encounter on almost all PR (Session resume using tickets, DTLS: openssl client test case see #5012) thus we can consider that this PR passed CI.
The requirement of minimum 15 bytes for output buffer in
psa_aead_finish() and psa_aead_verify() does not apply
to the built-in implementation of the GCM.
Alternative implementations are expected to verify the
length of the provided output buffers and to return
the MBEDTLS_ERR_GCM_BUFFER_TOO_SMALL in case the
buffer length is too small.
Signed-off-by: Mateusz Starzyk <mateusz.starzyk@mobica.com>
The previous implementation was misparsed in constructs like
`if (condition) MBEDTLS_IGNORE_RETURN(...); else ...;`.
Implement it as an expression, tested with GCC, Clang and MSVC.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
This macro is not used inside the library yet, but may be used in deprecated
functions in the future, if a function returning void has to change to
returning an error. It may also be useful in user code, so it is in a public
header.
Signed-off-by: Mateusz Starzyk <mateusz.starzyk@mobica.com>
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
This option only gated an ability to set a callback,
but was deemed unnecessary as it was yet another define to
remember when writing tests, or test configurations. Fixes#4653.
Signed-off-by: Andrzej Kurek <andrzej.kurek@arm.com>
MBEDTLS_CHECK_RETURN_TYPICAL defaults off, but is enabled if
MBEDTLS_CHECK_RETURN_WARNING is enabled at compile time.
(MBEDTLS_CHECK_RETURN_CRITICAL is always enabled.)
The default is off so that a plausible program that builds with one version
of Mbed TLS in the default configuration will still build under the next
version.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
This is normally equivalent, but works even if some other header defines a
macro called warn_unused_result.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
An empty expansion is possible, but as documented its effect is to disable
the feature, so that isn't a good example. Instead, use the GCC
implementation as the default: it's plausible that it could work even on
compilers that don't advertise themselves as sufficiently GCC-like to define
__GNUC__, and if not it gives users a concrete idea of what the macro is
supposed to do.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
For all of these functions, the only possible failures are a hardware
accelerator (not possible unless using an ALT implementation), an internal
error or runtime corruption.
Exception: the self-tests, which serve little purpose if their status isn't
tested.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Define macros MBEDTLS_CHECK_RETURN_CRITICAL, MBEDTLS_CHECK_RETURN_TYPICAL
and MBEDTLS_CHECK_RETURN_OPTIONAL so that we can indicate on a
function-by-function basis whether checking the function's return value is
almost always necessary (CRITICAL), typically necessary in portable
applications but unnecessary in some reasonable cases (TYPICAL), or
typically unnecessary (OPTIONAL).
Update the documentation of MBEDTLS_CHECK_RETURN accordingly. This is split
between the user documentation (Doxygen, in config.h) and the internal
documentation (non-Doxygen, in platform_util.h, of minor importance since
the macro isn't meant to be used directly).
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Declare all AES and DES functions that return int as needing to have
their result checked, and do check the result in our code.
A DES or AES block operation can fail in alternative implementations of
mbedtls_internal_aes_encrypt() (under MBEDTLS_AES_ENCRYPT_ALT),
mbedtls_internal_aes_decrypt() (under MBEDTLS_AES_DECRYPT_ALT),
mbedtls_des_crypt_ecb() (under MBEDTLS_DES_CRYPT_ECB_ALT),
mbedtls_des3_crypt_ecb() (under MBEDTLS_DES3_CRYPT_ECB_ALT).
A failure can happen if the accelerator peripheral is in a bad state.
Several block modes were not catching the error.
This commit does the following code changes, grouped together to avoid
having an intermediate commit where the build fails:
* Add MBEDTLS_CHECK_RETURN to all functions returning int in aes.h and des.h.
* Fix all places where this causes a GCC warning, indicating that our code
was not properly checking the result of an AES operation:
* In library code: on failure, goto exit and return ret.
* In pkey programs: goto exit.
* In the benchmark program: exit (not ideal since there's no error
message, but it's what the code currently does for failures).
* In test code: TEST_ASSERT.
* Changelog entry.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Put this macro before a function declaration to indicate that its result
must be checked. This commit supports GCC-like compilers and MSVC >=2012.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
