Any timing variance dependant on the output of this function enables a
Bleichenbacher attack. It is extremely difficult to use safely.
In the Marvin attack paper
(https://people.redhat.com/~hkario/marvin/marvin-attack-paper.pdf) the
author suggests that implementations of PKCS 1.5 decryption that don't
include a countermeasure should be considered inherently dangerous.
They suggest that all libraries implement the same countermeasure, as
implementing different countermeasures across libraries enables the
Bleichenbacher attack as well.
This is extremely fragile and therefore we don't implement it. The use
of PKCS 1.5 in Mbed TLS implements the countermeasures recommended in
the TLS standard (7.4.7.1 of RFC 5246) and is not vulnerable.
Add a warning to PKCS 1.5 decryption to warn users about this.
Signed-off-by: Janos Follath <janos.follath@arm.com>
We can't have a public header or library file reference our test
environment (except possibly under test-only options, and even so, it would
be with great reluctance). This breaks the build for other people.
Fix#8259.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Centralize it in a new file psa/config_adjust_keypair_types.h. I think
this file indeed belongs in include/psa (as opposed to include/mbedtls)
because it only touches PSA_WANT symbols (no MBEDTLS_PSA symbols), and
implements things that are described in psa-conditional-inclusion.md.
The code is not new, just moved from config_psa.h and
config_adjust_legacy_from_psa.h where is was intermingled with handling
of ACCEL/BUILTIN symbols. (git's --color-moved option will hardly help
in checking that assertion, due to the way things were intermixed.)
Note: the parts about BUILTIN in config_psa.h were not moved, just
removed for now. They belong to
include/mbedtls/config_adjust_legacy_from_psa.h and will be
re-added there in a future commit which will completely re-organize the
handling or ACCEL/BUILTIN for ECC.
See comments inside the commit about placement of this file relative to
others.
Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
Only document it with the PSA configuration, not for
MBEDTLS_ECP_DP_SECP256R1_ENABLED, since p256m can't be used with the classic
API.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Conflicts:
* `include/psa/crypto_sizes.h`: the addition of the `u` suffix in this branch
conflicts with the rework of the calculation of `PSA_HASH_MAX_SIZE` and
`PSA_HMAC_MAX_HASH_BLOCK_SIZE` in `development`. Use the new definitions
from `development`, and add the `u` suffix to the relevant constants.
aca31654e6 removed a sentence with copypasta
refering to PBKDF2 instead of XTS. Restore that comment but fix the
copypasta.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
This fixes a warning from some compilers (e.g. MSVC) about comparisons
between signed and unsigned values in perfectly reasonable code. In
particular, there was one such warning in psa_pbkdf2_hmac_set_password.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Add missing dependency of the unauthenticated
cipher CCM* without tag builtin implementation
on builtin cipher.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
