It was initially motivated by the fact that the PSA Crypto APIs
themselves were not stable. In the meantime, PSA Crypto has reached
1.0.0 so this no longer applies.
If we want user to be able to fully benefit from PSA in order to
isolate long-term secrets, they need to be able to use the new APIs with
confidence. There is no reason to think those APIs are any more likely
to change than any of our other APIs, and if they do, we'll follow the
normal process (deprecated in favour of a new variant).
For reference, the APIs in question are:
mbedtls_pk_setup_opaque() // to use PSA-held ECDSA/RSA keys in TLS
mbedtls_ssl_conf_psk_opaque() // for PSA-held PSKs in TLS
mbedtls_ssl_set_hs_psk_opaque() // for PSA-held PSKs in TLS
mbedtls_cipher_setup_psa() (deprecated in 3.2)
mbedtls_pk_wrap_as_opaque() (documented internal, to be removed in 3.2)
Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
Add a platform function mbedtls_setbuf(), defaulting to setbuf().
The intent is to allow disabling stdio buffering when reading or writing
files with sensitive data, because this exposes the sensitive data to a
subsequent memory disclosure vulnerability.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Document that MBEDTLS_SSL_KEEP_PEER_CERTIFICATE is required by MBEDTLS_SSL_PROTO_TLS1_3
Fully validated by the internal CI. No need to wait for the open one.
Also have check_config.h enforce this. And MBEDTLS_SSL_EXPORT_KEYS has been removed,
so no longer mention it.
Signed-off-by: Tom Cosgrove <tom.cosgrove@arm.com>
This is an external function, so in the absence of link-time
optimisation (LTO) the compiler can't know anything about it and has to
call it the number of times it's called in the source code.
This only matters for pk_ec, but change pk_rsa as well for the sake of
uniformity.
Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
Trusting the caller to perform the appropriate check is both risky, and
a bit user-unfriendly. Returning NULL on error seems both safer
(dereferencing a NULL pointer is more likely to result in a clean crash,
while mis-casting a pointer might have deeper, less predictable
consequences) and friendlier (the caller can just check the return
value for NULL, which is a common idiom).
Only add that as an additional way of using the function, for the sake
of backwards compatibility. Calls where we know the type of the context
for sure (for example because we just set it up) were legal and safe, so
they should remain legal without checking the result for NULL, which
would be redundant.
Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
The previous wording "ensure it holds an XXX" context did not mean
anything without looking at the source.
Looking at the source, the criterion is:
- for mbedtls_pk_rsa(), that the info structure uses rsa_alloc_wrap;
- for mbedtls_pk_ec(), that it uses eckey_alloc_wrap or
ecdsa_alloc_wrap, since mbedtls_ecdsa_context is a typedef for
mbedtls_ecp_keypair. (Note that our test code uses mbedtls_pk_ec() on
contexts of type MBEDTLS_PK_ECDSA.)
Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
Promise that we will try to keep backward compatibility with basic driver
usage, but not with more experimental aspects.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
This was intended as experimental, and we've been saying for a long time
that it's superseded by the "unified driver interface", but we hadn't
documented that inside the Mbed TLS source code. So announce it as
deprecated.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Certain numerical values are written to the key store. Changing those
numerical values would break the backward compatibility of stored keys. Add
a note to the affected types. Add comments near the definitions of affected
values.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Move the definition of the accessor so that it is not defined
within the MBEDTLS_X509_CRT_WRITE_C guards. Thus remove the
dependency from the test and test cases.
Signed-off-by: Thomas Daubney <thomas.daubney@arm.com>
