Note a possible microoptimization in mbedtls_mpi_mul_hlp that I tried
in the hope of reducing the number of allocations, but turned out to
be counterproductive.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Rewrite mbedtls_mpi_mul_int to call mpi_mul_hlp directly rather than
create a temporary mpi object. This has the benefit of not performing
an allocation when the multiplication is in place (mpi operand aliased
with the result) and the result mpi is large enough.
This saves about 40% of the calloc() calls in test_suite_ecp. There is
no measurable performance difference on my Linux PC.
The cost is a few bytes in bignum.o.
When there is no aliasing, or when there is aliasing but the mpi
object needs to be enlarged, the performance difference is negligible.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
mbedtls_mpi_sub_abs systematically allocated a new mpi when the result
was aliased with the right operand (i.e. X = A - X). This aliasing
very commonly happens during ECP operations. Rewrite the function to
allocate only if the result might not fit otherwise.
This costs a few bytes of code size in bignum.o, and might make
mbedtls_mpi_sub_abs very very slightly slower when no reallocation is
done. However, there is a substantial performance gain in ECP
operations with Montgomery curves (10-20% on my PC).
test_suite_ecp drops from 1422794 to 1271506 calls to calloc().
This commit also fixes a bug whereby mbedtls_mpi_sub_abs would leak
memory when X == B (so TB was in use) and the result was negative.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Reduce the code size, stack consumption and heap consumption in
fix_negative by encoding the special-case subtraction manually.
* Code size: ecp_curves.o goes down from 7837B down to 7769 in a
sample Cortex-M0 build with all curves enabled. The savings come
from not having to set up C in INIT (which is used many times) and
from not having to catch errors in fix_negative.
* Stack consumption: get rid of C on the stack.
* Heap: mbedtls_mpi_sub_abs with destination == second operand would
make a heap allocation. The new code doesn't do any heap allocation.
* Performance: no measurable difference.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
fix_negative allocates memory for its result. The calling site didn't
check the return value, so an out-of-memory error could lead to an
incorrect calculation. Fix this.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Fix a memory leak in mbedtls_mpi_sub_abs when the output parameter is
aliased to the second operand (X = A - X) and the result is negative.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
The previous revision of guards around SHA_224 and SHA_384 were not
correct. This set of changes ensures the proper code is available
when SHA_224 and SHA_384 are enabled for use.
Signed-off-by: John Durkop <john.durkop@fermatsoftware.com>
Removed unecessary checks on the ALG_SHA_224 and ALG_SHA_384 since
those are handled in config_psa.h by ensuring the correct _C is
included. Reformatted config_psa.h to be alphabetical and made the
assignments line up correctly for consistency. Fixed the guards
for ALG_SHA_224 and ALG_SHA_384 to be correct in the crypto library
source.
Signed-off-by: John Durkop <john.durkop@fermatsoftware.com>
This set of changes converts all the previous MBEDTLS_*_C guards in
the crypto library to use the new MBEDTLS_PSA_BUILTIN_ guards for
hash algorithms.
Signed-off-by: John Durkop <john.durkop@fermatsoftware.com>
With the addition of hash algorithms to crypto config there
are new dependencies for SHA224 and SHA384 that need to be confirmed
for those hashes to be used.
Signed-off-by: John Durkop <john.durkop@fermatsoftware.com>
mbedtls_ctr_drbg_set_reseed_interval() and
mbedtls_hmac_drbg_set_reseed_interval() can now be called before
their seed functions and the reseed_interval value will persist.
Previously it would be overwritten with the default value.
*_drbg_reseed_interval is now set in init() and free().
mbedtls_ctr_drbg_free() and mbedtls_hmac_drbg_free() now
reset the drbg context to the state immediately after init().
Tests:
- Added test to check that DRBG reseeds when reseed_counter
reaches reseed_interval, if reseed_interval set before seed
and reseed_interval is less than MBEDTLS_CTR_DRBG_RESEED_INTERVAL.
Signed-off-by: gacquroff <gavina352@gmail.com>
`finish_sha384_t` was made more generic by using `unsigned char*`
instead of `unsigned char[48]` as the second parameter.
This change tries to make the function casting more robust against
future improvements of gcc analysis.
Signed-off-by: Rodrigo Dias Correa <rodrigo@correas.us>
This commit fixes the same warning fixed by baeedbf9, but without
wasting RAM. By casting `mbedtls_sha512_finish_ret()`, `padbuf`
could be kept 48 bytes long without triggering any warnings.
Signed-off-by: Rodrigo Dias Correa <rodrigo@correas.us>
GCC 11 generated a warning because `padbuf` was too small to be
used as an argument for `mbedtls_sha512_finish_ret`. The `output`
parameter of `mbedtls_sha512_finish_ret` has the type
`unsigned char[64]`, but `padbuf` was only 48 bytes long.
Even though `ssl_calc_finished_tls_sha384` uses only 48 bytes for
the hash output, the size of `padbuf` was increased to 64 bytes.
Signed-off-by: Rodrigo Dias Correa <rodrigo@correas.us>
In GCC 11, parameters declared as arrays in function prototypes
cannot be declared as pointers in the function definition. The
same is true for the other way around.
The definition of `mbedtls_aes_cmac_prf_128` was changed to match
its public prototype in `cmac.h`. The type `output` was
`unsigned char *`, now is `unsigned char [16]`.
In `ssl_tls.c`, all the `ssl_calc_verify_*` variants now use pointers
for the output `hash` parameter. The array parameters were removed
because those functions must be compatible with the function pointer
`calc_verify` (defined in `ssl_internal.h`).
Signed-off-by: Rodrigo Dias Correa <rodrigo@correas.us>
Rename functions to get a key slot:
. to make their naming more consistent
. to emphasize that those functions set a lock on the
key slot they return to protect it from being wiped
out and re-used while some part of the library
is accessing it.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
Move the return of the identifier of a created key from
psa_start_key_creation() to psa_finish_key_creation().
That way in case of creation error, it is less likely to
return the identifier that was temporarily assigned to
the key while trying to create it.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
Decrement the slot access count in psa_finish_key_creation()
when the finalization succeeds instead of in functions calling
psa_finish_key_creation(). That way the decrementation cannot
be forgotten and it reduces the code size.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
Special handling of volatile key identifiers is not
needed eventually, they can be handled just as
key identifier in the vendor range.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
In case of a volatile key identifier, no need to check first
the validity of the key identifier, a volatile key identifier
is valid.
Move to a forward search for non-volatile key identifiers as
now key slots with small index are allocated first by
psa_get_empty_key_slot().
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
Moved new check_crypto_config.h file from include/psa to library
directory and the file is now included from *.c instead of the
crypto_config.h file. Fixed guards in PSA crypto library based
on review comments for new PSA crypto config features.
Signed-off-by: John Durkop <john.durkop@fermatsoftware.com>
Complement to 0a8352b4: peer_pmslen is not initialized when decryption
fails, so '|= peer_pmslen' may access uninitialized memory, as indicated
by Frama-C/Eva.
Co-authored-by: Gilles Peskine <gilles.peskine@arm.com>
Signed-off-by: André Maroneze <maroneze@users.noreply.github.com>
Simplify the guards on MBEDTLS_ERROR_C and MBEDTLS_ERROR_STRERROR_DUMMY.
No longer include superfluous headers and definition: platform.h is
only needed for MBEDTLS_ERROR_C; time_t is not needed at all.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
There was one lingering MBEDTLS_MD_C that needed to be removed since
it is no longer needed.
Signed-off-by: John Durkop <john.durkop@fermatsoftware.com>
Revised the placement of various new MBEDTLS_PSA_BUILTIN_xxx
guards based on review comments. Corrected guards in psa
test driver to use _ACCEL version instead of _BUILTIN version.
Updated check_config_psa.h to include additional dependency checks
for more algorithms. Renamed some of the new tests to be a little
more clear on the purpose.
Signed-off-by: John Durkop <john.durkop@fermatsoftware.com>
For consistency across the code base, prefer
persistent over permanent to qualify a key
stored in persistent storage.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
When looking for an empty key slot to store
the description of a key, if all key slots
are in use, reuse the first encountered
and unaccessed key slot containing the
description of a permanent key.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
When psa_close/destroy/purge_key is called, do not
reset a key slot containing the description
of a persistent key if it is currently accessed.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
Add a counter of unaccessed slots and use it
in tests to check that at the end of PSA tests
all key slot are unaccessed.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
Add key slot access counter to be able to
state if a key slot containing the description
of a permanent key can be reset or reset
and re-used.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
