The sequence of calls starts-update-starts-update-finish is not a
guaranteed valid way to abort an operation and start a new one. Our
software implementation just happens to support it, but alt
implementations may very well not support it.
Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
To simplify the documentation, and because there are only two realistic
behaviors in practice, only allow two behaviors for multipart output:
immediate output, or buffering of the last partial block.
State some simple rules that applications can follow if they don't care about
the details.
Explicitly state how much output is needed for finish(). Only require the
buffer size to be the size of the actual output, not the size of the potential
output in the worst case. Rename the parameter from output_len to output_size
since it's a buffer size and not necessarily the length of the data.
No longer guarantee that the built-in implementation produces immediate
output.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Commit removes mode parameter from
mbedtls_rsa_pkcs1_verify and propagates the
change throughout the codebase.
Signed-off-by: Thomas Daubney <thomas.daubney@arm.com>
Commit removes p_rng from mbedtls_rsa_pkcs1_verify
since p_rng has no relevance following the removal
of f_rng from this function.
Signed-off-by: Thomas Daubney <thomas.daubney@arm.com>
Commit removes f_rng parameter from
mbedtls_rsa_pkcs1_verify as a prerequisite
to removing the mode parameter. f_rng no
longer has relevance in this function if
mode is removed.
Signed-off-by: Thomas Daubney <thomas.daubney@arm.com>
Commit removes the mode param from
mbedtls_rsa_rsassa_pss_sign and propagates
the changes throughout the codebase.
Signed-off-by: Thomas Daubney <thomas.daubney@arm.com>
Commit removes the mode parameter from
mbedtls_rsa_rsassa_pkcs1_v15_sign and
propagates the change throughout the
codebase.
Signed-off-by: Thomas Daubney <thomas.daubney@arm.com>
Commit removes the mode parameter from
mbedtls_rsa_pkcs1_sign and progagates the
change to all relevant parts of the codebase.
Signed-off-by: Thomas Daubney <thomas.daubney@arm.com>
This commit modifies the typedef of
mbedtls_pk_rsa_alt_sign_func and propagates the
associated changes throughout the codebase.
Signed-off-by: Thomas Daubney <thomas.daubney@arm.com>
Run `make generated_files` to generate the automatically generated
C source files and build scripts.
Run `make neat` to remove all automatically generated files, even C
source files and build scripts.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Removes mode parameter from
mbedtls_rsa_rsaes_oaep_encrypt and propagates
changes throughout the codebase.
Signed-off-by: Thomas Daubney <thomas.daubney@arm.com>
Removal of mode parameter from
mbedtls_rsa_rsaes_pkcs1_v15_encrypt. This commit
propagates the change to all relevant function calls
and tests.
Signed-off-by: Thomas Daubney <thomas.daubney@arm.com>
Removal of the mode parameter from
mbedtls_rsa_pkcs1_encrypt function. This change
is propagated throughout the codebase and to
relevant tests.
Signed-off-by: Thomas Daubney <thomas.daubney@arm.com>
mbedtls_ssl_{get,set}_session() exhibited idempotent behaviour
in Mbed TLS 2.x. Multiple calls to those functions are not useful
in TLS 1.2, and the idempotent nature is unsuitable for support of
TLS 1.3 which introduces the availabilty to offer multiple tickets
for resumption, as well as receive multiple tickets.
In preparation for TLS 1.3 support, this commit relaxes the semantics
of `mbedtls_ssl_{get,set}_session()` by allowing implementations to
fail gracefully, and leveraging this freedom by modifying the
existing TLS 1.2 implementation to only accept one call to
`mbedtls_ssl_{get,set}_session()` per context, and non-fatally
failing all subsequent invocations.
For TLS 1.3, it will be leveraged by making multiple calls to
`mbedtls_ssl_get_session()` issue one ticket a time until no more
tickets are available, and by using multiple calls to
`mbedtls_ssl_set_session()` to allow the client to offer multiple
tickets to the server.
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
The changed logic is to try a sign-message driver (opaque or transparent);
if there isn't one, fallback to builtin sofware and do the hashing,
then try a sign-hash driver. This will enable to the opaque driver
to fallback to software.
Signed-off-by: gabor-mezei-arm <gabor.mezei@arm.com>
To avoid code duplication of the old-style SE interface usage
call psa_driver_wrapper_sign/verify_hash function instead of
the direct internal functions.
Signed-off-by: gabor-mezei-arm <gabor.mezei@arm.com>
Use common funtion for psa_sign_hash and psa_sign_message and one for
psa_verify_hash and psa_verify_message to unify them.
Signed-off-by: gabor-mezei-arm <gabor.mezei@arm.com>
The reference session cache implementation may end up storing multiple
sessions associated to the same session ID if the set()-call for the
second session finds an outdated cache entry prior to noticing the entry
with the matching session ID. While this logically overwrites the existing
entry since we always search the cache in order, this is at least a waste
of resources.
This commit fixes this by always checking first whether the given ID is
already present in the cache.
It also restructures the code for easier readability.
Fixes#4509.
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
The output parameter of mbedtls_sha256_finish_ret and mbedtls_sha256_ret
now has a pointer type rather than array type. This removes spurious
warnings in some compilers when outputting a SHA-224 hash into a
28-byte buffer.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Remove a kludge to avoid a warning in GCC 11 when calling
mbedtls_sha512_finish_ret with a 48-byte output buffer. This is correct
since we're calculating SHA-384. When mbedtls_sha512_finish_ret's output
parameter was declared as a 64-byte array, GCC 11 -Wstringop-overflow
emitted a well-meaning, but inaccurate buffer overflow warning, which we
tried to work around (successfully with beta releases but unsuccessfully
with GCC 11.1.0 as released). Now that the output parameter is declared as a
pointer, no workaround is necessary.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
The output parameter of mbedtls_sha512_finish_ret and mbedtls_sha512_ret
now has a pointer type rather than array type. This removes spurious
warnings in some compilers when outputting a SHA-384 hash into a
48-byte buffer.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Remove mode param from mbedtls_rsa_rsaes_pkcs1_v15_decrypt
and also modify and remove relevant tests.
Signed-off-by: Thomas Daubney <thomas.daubney@arm.com>
Removing the mode parameter from the mbedtls_rsa_rsaes_oaep_decrypt
function. The change is progagated to all function calls, including in
test suite .function files. Additionally fully removing one test
where the wrong mode was being tested.
Signed-off-by: Tom Daubney <Thomas.Daubney@arm.com>
Signed-off-by: Thomas Daubney <thomas.daubney@arm.com>
The mode parameter has been removed from the
mbedtls_rsa_pkcs1_decrypt function. The change
has been progagated to all function calls,
including in test suite .function files.
Signed-off-by: Thomas Daubney <thomas.daubney@arm.com>
Removed a conditional compilation block
relating to MBEDTLS_PKCS1_V15 in
rsa_pkcs1_verify_raw function that was no
longer relevant.
Signed-off-by: Thomas Daubney <thomas.daubney@arm.com>
Building the library without entropy sources negates any and all security
provided by the library.
This option was originally requested a relatively long time ago and it
does not provide any tangible benefit for users any more.
Signed-off-by: Mateusz Starzyk <mateusz.starzyk@mobica.com>
Sometime user may forget to call mbedtls_aes_setkey_enc or
mbedtls_aes_setkey_dec before mbedtls_aes_crypt_ecb and then
the code normally crash inside the assembly code. With this
patch, the code will stop inside the C source code which is
more convenient to locate the problem.
Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
Change-Id: I0e1d6b219f8709f8acaee5f345344335fc82fed3
Since they became equivalent after moving the is_sign checking back to
the PSA core, they're now redundant, and the generic mac_setup function
can just be called directly.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
Since a valid mac operation context would guarantee that the stored
mac size is >= 4, it wasn't immediately obvious that the zero-length
check is meant for static analyzers and a bit of robustness.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
Rework SHA224 and SHA283 documentation.
Define MBEDTLS_SHAxxx_C options in alphabetic order.
Fix SHA224 and SHA384 dependencies in test suites.
Signed-off-by: Mateusz Starzyk <mateusz.starzyk@mobica.com>
The PSA core checks the key type and algorithm combination before
calling the driver, so the driver doesn't have to do this once more.
The PSA core will also not start an operation with a requested length
which is larger than the full MAC output size, so the output length check
in the driver isn't needed as long as the driver returns an error on
mac_setup if it doesn't support the underlying hash algorithm.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
It makes sense to do the length checking in the core rather than expect
each driver to deal with it themselves. This puts the onus on the core to
dictate which algorithm/key combinations are valid before calling a driver.
Additionally, this commit also updates the psa_mac_sign_finish function
to better deal with output buffer sanitation, as per the review comments
on #4247.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
As psa_mac_sign_finish / psa_mac_verify_finish already checks that the
operation structure is valid (id is non-zero), the driver itself doesn't
have to check for that anymore. If the operation has a driver ID assigned,
it means that driver has returned success from its setup function, so the
algorithm value will be set correctly.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
The key passed to the driver has been imported by the PSA Core, meaning
its length has already been verified, and the driver can rely on the
buffer length and key attributes being consistent.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
This means there is no longer a need to have an internal HMAC API, so
it is being removed in this commit as well.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
Prefix with 'mbedtls_psa' as per the other types which implement some
sort of algorithm in software.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
Now renamed to mbedtls_psa_safer_memcmp, it provides a single location
for buffer comparison.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
The purpose of key_set was to guard the operation structure from being
used for update/finish before a key was set. Now that the implementation
fully adheres to the PSA API, that function is covered by the `alg`
variable instead. It's set to the algorithm in use when a key is set, and
is zero when the operation is reset/invalid.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
* Early return since there's nothing to clean up
* Get rid of unnecessary local variable
* Check algorithm validity for MAC in the PSA core instead of in the driver
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
Apparently it was at some point assumed that there would be
support for MAC algorithms with IV, but that hasn't been
implemented yet. Until that time, these context structure
members are superfluous and can be removed.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
Typedef'ed structures are suffixed _t
Also updated the initialiser macro with content that actually
matches the structure's content.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
Since HMAC moved into its own compilation unit, the internal API needed
to be documented and finalized. This means no more reaching deep into
the operation structure from within the PSA Crypto core. This will make
future refactoring work easier, since internal HMAC is now opaque to the
core.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
Step 3/x in moving the driver. Separate commits should make for easier
review.
Additional changes on top of code movement:
* Copied the implementation of safer_memcmp from psa_crypto into
psa_cipher_mac since the mac_verify driver implementation
depends on it, and it isn't available through external linkage
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
Step 2/x in moving the driver. Separate commits should make for easier
review.
Additional changes on top of code movement:
* Early-return success on input with zero-length to mac_update, to
avoid NULL pointers getting passed into the driver dispatch
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
Step 1/x in moving the driver. Separate commits should make for easier
review.
Additional changes on top of just moving code:
* Added a sanity check on the key buffer size for CMAC.
* Transfered responsibility for resetting the core members of the
PSA MAC operation structure back to the core (from the driver
wrapper layer)
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
This is a temporary measure. Other operations in the PSA Core which rely
on this internal HMAC API should be rewritten to use the MAC API instead,
since they can then leverage accelerated HMAC should a platform provide
such acceleration support.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
Zephyr's native posix port define _POSIX_C_SOURCE with a higher value
during the build, so when mbedTLS defines it with a different value
breaks the build.
As Zephyr is already defining a higher value is guaranteed that mbedTLS
required features will be available. So, just define it in case it was
not defined before.
[taken from Zephyr mbedtls module:
76dcd6eeca]
Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
Signed-off-by: David Brown <david.brown@linaro.org>
Move the key buffer size calculation code under
tests to avoid check-names.sh to complain about
"likely macros with typos".
This removes the calculation of key buffer
sizes for the test driver from the wrapper based on
static size data. But the code is still there in test
code to be used when we go back to work on the
generation of the driver wrapper.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
Handling the receipt of a handshake record after the initial handshake
requires non-trivial logic depending on the protocol version and the
endpoint. This logic is currently embedded in mbedtls_ssl_read().
With the introduction of support for [D]TLS 1.3, the logic will become
even more complex, since [D]TLS 1.3 drops support for renegotiation --
which in [D]TLS 1.2 is the main purpose of post-handshake handshake
messages -- but instead introduces numerous other post-handshake
handshake messages.
In order to pave the way for those changes, this commit improves
readability and maintainability of mbedtls_ssl_read() by moving
the TLS <=1.2 logic for handling post-handshake handshake messages
into a separate helper function ssl_handle_hs_message_post_handshake().
The logic of the code is entirely unchanged.
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
The server-side `Certificate` handshake message writer checks
whether a certificate is present, and if not fails with:
```
MBEDTLS_ERR_SSL_CERTIFICATE_REQUIRED
```
This should never happen, since the library checks the presence
of a suitable certificate before picking a ciphersuite. It is
therefore more suitable to convert this check into an assertion,
and fail with MBEDTLS_ERR_SSL_INTERNAL_ERROR upon failure.
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
This commit removes the unused error code
```
MBEDTLS_ERR_SSL_INVALID_VERIFY_HASH
```
from the public API for Mbed TLS 3.0.
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
The error code MBEDTLS_ERR_SSL_INVALID_VERIFY_HASH is only
returned from the internal function
```
mbedtls_ssl_set_calc_verify_md()
```
Moreover, at every call-site of this function, it is only
checked whether the return value is 0 or not, while the
exact return value is irrelevant.
The behavior the library is therefore unchanged if we return 1
instead of MBEDTLS_ERR_SSL_INVALID_VERIFY_HASH in
`mbedtls_ssl_set_calc_verify_md()`. This commit makes this change.
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
This error is used when the output buffer isn't large enough
to hold our own certificate.
In the interest of cleaning up the error space for 3.0, this commit
removes MBEDTLS_ERR_SSL_CERTIFICATE_TOO_LARGE and replaces its single
use by MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL.
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
The SSL error code MBEDTLS_ERR_SSL_PEER_VERIFY_FAILED is unused.
Remove it for Mbed TLS 3.0.
The code being unused comes as a surprise, at is seems to be
reasonable to report it to the user upon peer CRT verification
failure. However, this study (can potentially re-introduction
of the code) can be left for 3.x, while the error code removal
can only happen in 3.0.
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
The SSL error code MBEDTLS_ERR_SSL_UNKNOWN_CIPHER is unused.
Remove it for Mbed TLS 3.0 and leave a comment indicating the
gap in the error code space it creates.
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
pk_get_pk_alg will either return 0 or a pk error code. This means that
the error code will always be a high level module ID and so we just
return ret.
Signed-off-by: Chris Jones <christopher.jones@arm.com>
Although SHA512 is currently required to enable SHA384, this
is expected to change in the future. This commit is an
intermediate step towards fully separating SHA384 and SHA512.
check_config is the only module which enforces that SHA512 is
enabled together with SHA384.
Signed-off-by: Mateusz Starzyk <mateusz.starzyk@mobica.com>
The new compile-time option MBEDTLS_X509_REMOVE_INFO removes various
X.509 debugging strings and functionality, including
```
mbedtls_x509_crt_verify_info()
```
which ssl_client2.c and ssl_server2.c use to print human readable
descriptions of X.509 verification failure conditions. Those
conditions are also grepped for in numerous ssl-opt.sh tests.
Instead of disabling those tests if MBEDTLS_X509_REMOVE_INFO is set,
this commit essentially moves mbedtls_x509_crt_verify_info() to
ssl_client2.c and ssl_server2.c. However, instead of just copy-pasting
the code from x509_crt.c, the following approach is used:
A macro MBEDTLS_X509_CRT_ERROR_INFO_LIST is introduced which for each
verification failure condition invokes a user-defined macro X509_CRT_ERROR_INFO
with (a) the numerical error code, (b) the string presentation of the
corresponding error macro, (c) the info string for the error condition.
This macro can thus be used to generate code which somehow iterates over
the verifiation failure conditions, but the list of error conditions and
information strings is nowhere duplicated.
This is then used to re-implement mbedtls_x509_crt_verify_info() in
x509_crt.c and to provide a functionally equivalent (yet slightly different)
version in ssl_client2.c and ssl_server2.c in case MBEDTLS_X509_REMOVE_INFO
is set.
This way, little changes to ssl-opt.sh will be necessary in case
MBEDTLS_X509_REMOVE_INFO is set because the info strings for the
verification failure conditions will be printed regardless of whether
MBEDTLS_X509_REMOVE_INFO is set or not.
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
The introduction of positive options to control the presence
of pre-existing functionality breaks the build for users of
handwritten configurations.
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
Introduce MBEDTLS_X509_INFO to indicate the availability of the
mbedtls_x509_*_info() function and closely related APIs. When this is
not defined, also omit name and description from
mbedtls_oid_descriptor_t, and omit OID arrays, macros, and types that
are entirely unused. This saves several KB of code space.
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
Signed-off-by: Chris Jones <christopher.jones@arm.com>
Add implementation for MBEDTLS_PSA_CRYPTO_BUILTIN_KEYS
Merging as it has been ready for four days now and I prefer not having to go through other rebases especially given the coming change of scope of development (3.0 rather than 2.2x).
Improve comments explaining error code checking, fix incorrect comments
and make a small formatting fix.
Signed-off-by: Chris Jones <christopher.jones@arm.com>
* group setting of attributes before calling get_builtin_key
* return early instead of going to exit when no resources are allocated yet
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
The GCM interface now has separate functions to start the operation
and to pass the associated data.
This is in preparation for allowing the associated data to be passed
in chunks with repeatated calls to mbedtls_gcm_update_ad().
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Alternative implementations of GCM may delay the output of partial
blocks from mbedtls_gcm_update(). Add an output length parameter to
mbedtls_gcm_update() to allow such implementations to delay the output
of partial blocks. With the software implementation, there is no such
delay.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Alternative implementations of GCM may delay the output of partial
blocks from mbedtls_gcm_update(). Add an output parameter to
mbedtls_gcm_finish() to allow such implementations to pass the final
partial block back to the caller. With the software implementation,
this final output is always empty.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
mbedtls_gcm_update now accepts inputs of arbitrary size. There is no
longer a requirement that all calls except the last one pass a
multiple of 16 bytes.
This commit updates the library code and adjusts the GCM tests to
exercise arbitrarily aligned input sizes.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Leverage the fact that the get_builtin_key entrypoint returns a key's
attributes, such that a proper size for the builtin key's buffer can
be calculated through the driver's get_key_buffer_size hook.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
Since the loading attempt of a builtin key might be followed by trying
to load a persistent key, we can only wipe the allocated key data, not
the associated metadata.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
The macro always meant 'location', but was mistakenly named 'lifetime'.
Naming it location instead makes much more sense, and drives home the
conceptual differences between location and lifetime values.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
Instead of the full attributes struct, it now only takes/returns what it
actually needs to.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
Builtin key support for the test driver is always compiled in, and no
longer guarded by MBEDTLS_PSA_CRYPTO_BUILTIN_KEYS.
Parsing the key slot from the buffer by cast and assign instead of memcmp.
For exporting keys, the test driver no longer reaches into the key
identifier in order to check whether a key is builtin, but rather
assumes so based on the key buffer length. It's the driver's
responsibility to be able to detect the key material it returned as part
of the get_builtin_key operation.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
As part of test_psa_crypto_drivers, define a builtin symmetric
plus an ECC key on the test driver lifetime.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
According to the design in psa-driver-interface.md. Compiles without
issue in test_psa_crypto_drivers.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
This reverts commit c75d9f589b.
This was merged by mistake in development instead of development_3.0.
Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
This reverts commit 48f6d0d6e5.
This was merged by mistake in development instead of development_3.0.
Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
This reverts commit 9a86843470.
This was merged by mistake in development instead of development_3.0.
Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
An incorrect error code addition was spotted by the new invasive testing
infrastructure whereby pk_get_pk_alg will always return a high level
error or zero and pk_parse_key_pkcs8_unencrypted_der will try to add
another high level error, resulting in a garbage error code.
Apply the same fix from ae3741e8a to fix the bug.
Signed-off-by: Chris Jones <christopher.jones@arm.com>
Replace all occurences of error code addition in the library with the new
MBEDTLS_ERROR_ADD macro.
Signed-off-by: Chris Jones <christopher.jones@arm.com>
This commit improves the readability of the SSL session cache
reference implementation of mbedtls_ssl_cache_set() by moving
the logic for finding a suitable free slot for the session to
store into a static helper function.
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
Session-ID based session resumption requires that the resumed session
is consistent with the client's ClientHello in terms of choice of
ciphersuite and choice of compression.
This check was previously assumed to be performed in the session cache
implementation, which seems wrong: The session cache should be an id-based
lookup only, and protocol specific checks should be left to Mbed TLS.
This commit
- adds an explicit ciphersuite and compression consistency check after
the SSL session cache has been queried
- removes the ciphersuite and compression consistency check from
Mbed TLS' session cache reference implementation.
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
