We do not intend to support multithreaded testing in 2.28, so
introducing a C11 feature here is an unnecessary burden.
Signed-off-by: David Horstmann <david.horstmann@arm.com>
Upon further consideration we think that a remote attacker close to the
victim might be able to have precise enough timing information to
exploit the side channel as well. Update the Changelog to reflect this.
Signed-off-by: Janos Follath <janos.follath@arm.com>
The signature and naming of the Montgomrey initialisation function in
development and in the LTS was different. Align them for easier
readability and maintenance.
Signed-off-by: Janos Follath <janos.follath@arm.com>
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>
So far we needed it only locally here, but we will need calculating RR
for safe unblinding in RSA as well.
Signed-off-by: Janos Follath <janos.follath@arm.com>
Make sure that extra UNPOISON calls do not cause the poisoning counter
to underflow and wrap around.
Memory that is unpoisoned multiple times should remain unpoisoned.
Signed-off-by: David Horstmann <david.horstmann@arm.com>
Some platforms may support ASan but be C99-only (no C11 support).
These platforms will support ASan metatests but not memory poisoning,
which requires C11 features.
To allow for this, create a separate platform requirement, "poison",
in metatest.c to distinguish generic ASan metatests from ones that
require suppport for memory poisoning.
In practice our platforms support both, so run "poison" tests in
the same all.sh components where we run "asan" ones.
Signed-off-by: David Horstmann <david.horstmann@arm.com>
This allows unusually-nested memory poisoning to work correctly, since
it keeps track of whether any buffers are still poisoned, rather than
just disabling poisoning at the first call to the UNPOISON() macro.
Signed-off-by: David Horstmann <david.horstmann@arm.com>
Upon further consideration we think that a remote attacker close to the
victim might be able to have precise enough timing information to
exploit the side channel as well. Update the Changelog to reflect this.
Signed-off-by: Janos Follath <janos.follath@arm.com>
When we cannot memory poison due to platform constraints, do not attempt
to run memory poisoning metatests (but still run other ASan metatests).
Signed-off-by: David Horstmann <david.horstmann@arm.com>
Allow memory poisoning to be enabled and disabled at runtime using a
thread-local flag. This allows poisoning to be disabled whenever a PSA
function is called but not through the test wrappers, removing false
positive use-after-poisons.
Signed-off-by: David Horstmann <david.horstmann@arm.com>
The signature and naming of the Montgomrey initialisation function in
development and in the LTS was different. Align them for easier
readability and maintenance.
Signed-off-by: Janos Follath <janos.follath@arm.com>
secp224k1 is the one with 225-bit private keys.
The consequences of this mistake were:
* We emitted positive test cases for hypothetical SECP_R1_225 and
SECP_K1_224 curves, which were never executed.
* We emitted useless not-supported test cases for SECP_R1_225 and SECP_K1_224.
* We were missing positive test cases for SECP_R1_224 in automatically
generated tests.
* We were missing not-supported test cases for SECP_R1_224 and SECP_K1_225.
Thus this didn't cause test failures, but it caused missing test coverage
and some never-executed test cases.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Fix // comments stopping on 'n' instead of newlines. Also allow
backslash-newline in // comments.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
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>
