Zeroize local MAC variables used for CBC+HMAC cipher suites. In encryption,
this is just good hygiene but probably not needed for security since the
data protected by the MAC that could leak is about to be transmitted anyway.
In DTLS decryption, this could be a security issue since an adversary could
learn the MAC of data that they were trying to inject. At least with
encrypt-then-MAC, the adversary could then easily inject a datagram with
a corrected packet. TLS would still be safe since the receiver would close
the connection after the bad MAC.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
This patch adds explicit wording to state
that Two's complement is the official
supported signed integer representation.
Signed-off-by: Minos Galanakis <minos.galanakis@arm.com>
Under gcc11(+) both message and received would cause errors for
potentially being used uninitialised. We fixed many of these issues in
another PR, but this one is only seen under certain configs.
Signed-off-by: Paul Elliott <paul.elliott@arm.com>
This is technically an API break according to the unwritten rules of API
compatibility for Mbed TLS 2.x. However, it is very unlikely to affect any
realistic application, with the possible exception of applications that
define a global constant of type mbedtls_ssl_config.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
The makefile build specifies -L. -lmbedx509 -lmbedcrypto flags first,
and only then object files referencing symbols from those libraries.
In this order the linker will not add the linked libraries to the
DT_NEEDED section because they are not referenced yet (at least that
happens for me on ubuntu 20.04 with the default gnu compiler tools).
By first specifying the object files and then the linked libraries, we
do end up with libmbedx509 and libmbedcrypto in the DT_NEEDED sections.
This way running dlopen(...) on libmedtls.so just works.
Note that the CMake build does this by default.
Signed-off-by: Harmen Stoppels <harmenstoppels@gmail.com>
PSA_ALG_RSA_PSS algorithm now accepts only the same salt length for
verification that it produces when signing, as documented.
Fixes#4946.
Signed-off-by: Gilles Peskine <Gilles.Peskine@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>
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>
Combine the changelog entries for the memory constraints fix on
aarch64 and amd64, since these are essentially fixing the same
issue.
Signed-off-by: David Horstmann <david.horstmann@arm.com>
Add memory constraints to the aarch64 inline assembly in MULADDC_STOP.
This fixes an issue where Clang 12 and 13 were generating
non-functional code on aarch64 platforms. See #4962, #4943
for further details.
Signed-off-by: David Horstmann <david.horstmann@arm.com>
MULADDC_CORE reads from (%%rsi) and writes to (%%rdi). This fragment is
repeated up to 16 times, and %%rsi and %%rdi are s and d on entry
respectively. Hence the complete asm statement reads 16 64-bit words
from memory starting at s, and writes 16 64-bit words starting at d.
Without any declaration of modified memory, Clang 12 and Clang 13 generated
non-working code for mbedtls_mpi_mod_exp. The constraints make the unit
tests pass with Clang 12.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
It was unmaintained and untested, and the fear of breaking it was holding us
back. Resolves#4934.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
This parameter was set but not used, which was pointless. Clang 14 detects
this and legitimately complains.
Remove the parameter. This is an internal function, only called once. The
caller already has a sufficient check on the output buffer size which
applies in more cases, so there is no real gain in robustness in adding the
same check inside the internal function.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
The makefiles look for python3 on Unix-like systems where python is often
Python 2. This uses sh code so it doesn't work on Windows. On Windows, the
makefiles just assume that python is Python 3.
The code was incorrectly deciding not to try python3 based on WINDOWS_BUILD,
which indicates that the build is *for* Windows. Switch to checking WINDOWS,
which indicates that the build is *on* Windows.
Fix#4774
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
