You can't reuse a CTR_DRBG context without free()ing it and
re-init()ing. This generally happened to work, but was never
guaranteed. It could have failed with alternative implementations of
the AES module because mbedtls_ctr_drbg_seed() calls
mbedtls_aes_init() on a context which is already initialized if
mbedtls_ctr_drbg_seed() hasn't been called before, plausibly causing a
memory leak. Calling free() and seed() with no intervening init fails
when MBEDTLS_THREADING_C is enabled and all-bits-zero is not a valid
mutex representation. So add the missing free() and init().
mbedtls_ctr_drbg_seed() always set the entropy length to the default,
so a call to mbedtls_ctr_drbg_set_entropy_len() before seed() had no
effect. Change this to the more intuitive behavior that
set_entropy_len() sets the entropy length and seed() respects that and
only uses the default entropy length if there was no call to
set_entropy_len().
The former test-only function mbedtls_ctr_drbg_seed_entropy_len() is
no longer used, but keep it for strict ABI compatibility.
Move the definitions of mbedtls_ctr_drbg_seed_entropy_len() and
mbedtls_ctr_drbg_seed() to after they are used. This makes the code
easier to read and to maintain.
mbedtls_hmac_drbg_seed() always set the entropy length to the default,
so a call to mbedtls_hmac_drbg_set_entropy_len() before seed() had no
effect. Change this to the more intuitive behavior that
set_entropy_len() sets the entropy length and seed() respects that and
only uses the default entropy length if there was no call to
set_entropy_len().
* origin/pr/2860: (26 commits)
config.pl full: exclude MBEDTLS_CTR_DRBG_USE_128_BIT_KEY
mbedtls_hmac_drbg_set_entropy_len() only matters when reseeding
mbedtls_ctr_drbg_set_entropy_len() only matters when reseeding
mbedtls_ctr_drbg_seed: correct maximum for len
Add a note about CTR_DRBG security strength to config.h
Move MBEDTLS_CTR_DRBG_USE_128_BIT_KEY to the correct section
CTR_DRBG: more consistent formatting and wording
CTR_DRBG documentation: further wording improvements
CTR_DRBG: Improve the explanation of security strength
CTR_DRBG: make it easier to understand the security strength
HMAC_DRBG: note that the initial seeding grabs entropy for the nonce
Use standard terminology to describe the personalization string
Do note that xxx_drbg_random functions reseed with PR enabled
Consistently use \c NULL and \c 0
Also mention HMAC_DRBG in the changelog entry
HMAC_DRBG: improve the documentation of the entropy length
HMAC_DRBG documentation improvements clarifications
More CTR_DRBG documentation improvements and clarifications
Fix wording
Remove warning that the previous expanded discussion has obsoleted
...
The documentation of HMAC_DRBG erroneously claimed that
mbedtls_hmac_drbg_set_entropy_len() had an impact on the initial
seeding. This is in fact not the case: mbedtls_hmac_drbg_seed() forces
the entropy length to its chosen value. Fix the documentation.
The documentation of CTR_DRBG erroneously claimed that
mbedtls_ctr_drbg_set_entropy_len() had an impact on the initial
seeding. This is in fact not the case: mbedtls_ctr_drbg_seed() forces
the initial seeding to grab MBEDTLS_CTR_DRBG_ENTROPY_LEN bytes of
entropy. Fix the documentation and rewrite the discussion of the
entropy length and the security strength accordingly.
* origin/pr/2864:
Fix compilation error
Add const to variable
Fix endianity issue when reading uint32
Increase test suite timeout
Reduce stack usage of test_suite_pkcs1_v15
Reduce stack usage of test_suite_pkcs1_v21
Reduce stack usage of test_suite_rsa
Reduce stack usage of test_suite_pk
Explain how MBEDTLS_CTR_DRBG_ENTROPY_LEN is set next to the security
strength statement, rather than giving a partial explanation (current
setting only) in the documentation of MBEDTLS_CTR_DRBG_ENTROPY_LEN.
NIST and many other sources call it a "personalization string", and
certainly not "device-specific identifiers" which is actually somewhat
misleading since this is just one of many things that might go into a
personalization string.
Improve the formatting and writing of the documentation based on what
had been done for CTR_DRBG.
Document the maximum size and nullability of some buffer parameters.
This is a documentation-only change, but one that users who care about
NIST compliance may be interested in, to review if they're using the
module in a compliant way.
Document that a derivation function is used.
Document the security strength of the DRBG depending on the
compile-time configuration and how it is set up. In particular,
document how the nonce specified in SP 800-90A is set.
Mention how to link the ctr_drbg module with the entropy module.
The uint32 is given as a bigendian stream, in the tests, however,
the char buffer that collected the stream read it as is,
without converting it. Add a temporary buffer, to call `greentea_getc()`
8 times, and then put it in the correct endianity for input to `unhexify()`.
Reduce the stack usage of the `test_suite_pkcs1_v21` by reducing the
size of the buffers used in the tests, to a reasonable big enough size,
and change the size sent to the API to sizeof output.
Reduce the stack usage of the `test_suite_rsa` by reducing the
size of the buffers used in the tests, to a reasonable big enough size,
and change the data size to decrypt in the data file.
* State explicit whether several numbers are in bits or bytes.
* Clarify whether buffer pointer parameters can be NULL.
* Explain the value of constants that are dependent on the configuration.
* origin/pr/2826:
Enable MBEDTLS_MEMORY_DEBUG in memory buffer alloc test in all.sh
Remove unnecessary memory buffer alloc and memory backtrace 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
