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>
mbedtls_ssl_cache_get() and mbedtls_ssl_cache_set() returned 1 on many error
conditions. Change this to returning a negative MBEDTLS_ERR_xxx error code.
Completeness: after this commit, there are no longer any occurrences of
`return 1` or `ret = 1`.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
When ECDSA_SIGN_ALT but not ECDSA_VERIFY_ALT, mbedtls_ecdsa_can_do was not being defined causing mbedtls_ecdsa_verify_restartable to always fail
Signed-off-by: JonathanWitthoeft <jonw@gridconnect.com>
Also correct 'distro to 'dist' and update ubuntu to jammy and python
to 3.10 to hopefully fend off future issues. Too much got removed
when disabling travis and the Coverity scan build was failing on 'make
generated-files', due to lack of installed python dependencies
Signed-off-by: Paul Elliott <paul.elliott@arm.com>
- the \internal note said that calling cipher_init() first would be made
mandatory later, but the documention of the ctx parameter already said
the context had to be initialized...
- the documentation was using the word initialize for two different
meanings (calling setup() vs calling init()), making the documentation
of the ctx parameter quite confusing (you must initialize before you can
initialize...)
Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
