* mbedtls-2.16: (21 commits)
Exclude DTLS 1.2 only with older OpenSSL
Document the rationale for the armel build
Switch armel build to -Os
Add a build on ARMv5TE in ARM mode
Add changelog entry for ARM assembly fix
bn_mul.h: require at least ARMv6 to enable the ARM DSP code
Changelog entry for test certificates update
Change worktree_rev to HEAD for rev-parse
Add ChangeLog entry for entropy_nv_seed test case fix
entropy_nv_seed: cope with SHA-256
entropy_nv_seed: clean up properly
Add ChangeLog entry for undefined behavior fix in test_suite_nist_kw
Don't call memset after calloc
Adapt ChangeLog
ECP restart: Don't calculate address of sub ctx if ctx is NULL
Update certificates to expire in 2029
Update soon to be expired crl
Test that a shared library build produces a dynamically linked executable
Test that the shared library build with CMake works
Add a test of MBEDTLS_CONFIG_FILE
...
- a comment regarding the implementation of hmac_drbg_reseed_core()
was misplaced.
- add more references to the standard, and add details on how the
comments in the code refer to various parts of the standard.
Now function mbedtls_ssl_set_hostname is compile-time configurable
in config.h with define MBEDTLS_X509_REMOVE_HOSTNAME_VERIFICATION.
This affects to many x509 API's. See config.h for details.
According to SP800-90A, the DRBG seeding process should use a nonce
of length `security_strength / 2` bits as part of the DRBG seed. It
further notes that this nonce may be drawn from the same source of
entropy that is used for the first `security_strength` bits of the
DRBG seed. The present HMAC DRBG implementation does that, requesting
`security_strength * 3 / 2` bits of entropy from the configured entropy
source in total to form the initial part of the DRBG seed.
However, some entropy sources may have thresholds in terms of how much
entropy they can provide in a single call to their entropy gathering
function which may be exceeded by the present HMAC DRBG implementation
even if the threshold is not smaller than `security_strength` bits.
Specifically, this is the case for our own entropy module implementation
which only allows requesting at most 32 Bytes of entropy at a time
in configurations disabling SHA-512, and this leads to runtime failure
of HMAC DRBG when used with Mbed TLS' own entropy callbacks in such
configurations.
This commit fixes this by splitting the seed entropy acquisition into
two calls, one requesting `security_strength` bits first, and another
one requesting `security_strength / 2` bits for the nonce.
One test for running with MBEDTLS_ECDH_C on and one
for running MBEDTLS_ECDH_C off. Run ssl-opt.sh with Default, DTLS
and compatibility tests with TLS-ECDHE-ECDSA-WITH-AES-256-CBC-SHA.
compat.sh used to skip OpenSSL altogether for DTLS 1.2, because older
versions of OpenSSL didn't support it. But these days it is supported.
We don't want to use DTLS 1.2 with OpenSSL unconditionally, because we
still use legacy versions of OpenSSL to test with legacy ciphers. So
check whether the version we're using supports it.
tinyCrypt is still tested in the baremetal tests since it
is enabled in baremetal.h. Tests for minimal modifictions
of the default / full config enabling tinyCrypt will be
added elsewhere.
The use of tinyCrypt is restricted Secp256r1-only, and a check in
ssl_ciphersuite_is_match() ensures that an EC ciphersuite is chosen
only if the client advertised support for Secp256r1, too.
In a way inconsistent with the rest of the library restricting the
use of tinyCrypt to pure-ECDHE, the previous ServerKeyExchange writing
routine would use tinyCrypt also for ECDHE-PSK-based ciphersuites.
This commit fixes this.
Previously, MBEDTLS_KEY_EXCHANGE_ECDH[E]_XXX_ENABLED would imply
that MBEDTLS_ECDH_C is set, but with the introduction of tinyCrypt
as an alternative ECDH implementation, this is no longer the case.
tinyCrypt uses a global RNG without context parameter while Mbed TLS in its
default configuration uses RNG+CTX bound to the SSL configuration.
This commit restricts the use of tinyCrypt to configurations that use a
global RNG function with NULL context by setting MBEDTLS_SSL_CONF_RNG in
the configuration. This allows to define a wrapper RNG to be used by
tinyCrypt which maps to this global hardcoded RNG.
Eventually, all HS parsing/writing functions should take an arbitrary buffer +
length pair as their argument, and return MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL if
the provided buffer is too short. So far, we've only made a first step by
allowing to pass an arbitrary buffer, but don't yet add bounds checks
throughout. While deliberate for now, this must be clearly documented.
This makes grepping the functions more difficult, and also leads to compilation failures
when trying to build the library from a single source file (which might be useful for
code-size reasons).
