* State explicit whether several numbers are in bits or bytes.
* Clarify whether buffer pointer parameters can be NULL.
* Minor wording and formatting improvements.
Explain what how entropy input length is determined from the
configuration, and how this in turn determines the security strength.
Explain how the nonce is obtained during initialization.
* State explicit whether several numbers are in bits or bytes.
* Clarify whether buffer pointer parameters can be NULL.
* Clarify some terminology.
* Minor wording and formatting improvements.
* origin/pr/2828:
Enable MBEDTLS_MEMORY_DEBUG in memory buffer alloc test in all.sh
Remove unnecessary memory buffer alloc unsets
Disable DTLS proxy tests for MEMORY_BUFFER_ALLOC test
all.sh: restructure memory allocator tests
Add missing dependency in memory buffer alloc set in all.sh
Don't set MBEDTLS_MEMORY_DEBUG through `scripts/config.pl full`
Add cfg dep MBEDTLS_MEMORY_DEBUG->MBEDTLS_MEMORY_BUFFER_ALLOC_C
Add all.sh run with full config and ASan enabled
Add all.sh run with MBEDTLS_MEMORY_BUFFER_ALLOC_C enabled
Update documentation of exceptions for `config.pl full`
Adapt all.sh to removal of buffer allocator from full config
Disable memory buffer allocator in full config
Check dependencies of MBEDTLS_MEMORY_BACKTRACE in check_config.h
With the removal of MBEDTLS_MEMORY_BUFFER_ALLOC_C from the
full config, there are no tests for it remaining in all.sh.
This commit adds a build as well as runs of `make test` and
`ssl-opt.sh` with MBEDTLS_MEMORY_BUFFER_ALLOC_C enabled to all.sh.
Previously, numerous all.sh tests manually disabled the buffer allocator
or memory backtracting after setting a full config as the starting point.
With the removal of MBEDTLS_MEMORY_BACKTRACE and MBEDTLS_MEMORY_BUFFER_ALLOC_C
from full configs, this is no longer necessary.
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 Crypto' 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.
Fixes#237.
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.
Due to how the checking script is run in docker, worktree_rev is
ambiguous when running rev-parse. We're running it in the checked
out worktree, so we can use HEAD instead, which is unambiguous.
This test case was only executed if the SHA-512 module was enabled and
MBEDTLS_ENTROPY_FORCE_SHA256 was not enabled, so "config.pl full"
didn't have a chance to reach it even if that enabled
MBEDTLS_PLATFORM_NV_SEED_ALT.
Now all it takes to enable this test is MBEDTLS_PLATFORM_NV_SEED_ALT
and its requirements, and the near-ubiquitous MD module.
Call mbedtls_entropy_free on test failure.
Restore the previous NV seed functions which the call to
mbedtls_platform_set_nv_seed() changed. This didn't break anything,
but only because the NV seed functions used for these tests happened
to work for the tests that got executed later in the .data file.
