When passed an empty OID, mbedtls_oid_get_numeric_string would read one
byte from the zero-sized buffer and return an error code that depends on
its value. This is demonstrated by the test suite changes, which
check that an OID with length zero and an invalid buffer pointer does
not cause Mbed TLS to segfault.
Also check that second and subsequent subidentifiers are terminated, and
add a test case for that. Furthermore, stop relying on integer division
by 40, use the same loop for both the first and subsequent
subidentifiers, and add additional tests.
Signed-off-by: Demi Marie Obenour <demiobenour@gmail.com>
Timing attacks can be launched by any of the main 3 attackers. Clarify
exactly how these are covered.
Signed-off-by: Janos Follath <janos.follath@arm.com>
The block cipher exception affects both remote and local timing attacks.
Move them to the Caveats section and reference it from both the local
and the remote attack section.
Signed-off-by: Janos Follath <janos.follath@arm.com>
Originally for the sake of simplicity there was a single category for
software based attacks, namely timing side channel attacks.
Be more precise and categorise attacks as software based whether or not
they rely on physical information.
Signed-off-by: Janos Follath <janos.follath@arm.com>
When MBEDTLS_USE_PSA_CRYPTO is enabled, the application must call
psa_crypto_init() before directly or indirectly calling cipher or PK code
that will use PSA under the hood. Document this explicitly for some
functions.
To avoid clutter, this commit only documents the need to call
psa_crypto_init() in common, non-obvious cases: using a PK object that was
not constructed using PSA, X.509 processing, or setting up an SSL context.
Functions that are normally only called after such a function (for example,
using a cipher or PK context constructed from a PSA key), or where the need
for PSA is obvious because they take a key ID as argument, do not need more
explicit documentaion.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
With this change, "--list-components" will not list
"build_armcc" on the system which is not installed
with Arm Compilers.
Signed-off-by: Pengyu Lv <pengyu.lv@arm.com>
escalates into a buffer overflow in the application code
Signed-off-by: Stephan Koch <koch@oberon.ch>
Signed-off-by: Dave Rodgman <dave.rodgman@arm.com>
As tested in https://github.com/Mbed-TLS/mbedtls/issues/6790,
after introducing side-channel counter-measures to bignum,
the performance of RSA decryption in correlation to the
MBEDTLS_ECP_WINDOW_SIZE has changed.
The default value of 2 has been chosen as it provides best
or close-to-best results for tests on Cortex-M4 and Intel i7.
Signed-off-by: Andrzej Kurek <andrzej.kurek@arm.com>
