Key creation and key destruction for a key in a secure element both
require updating three pieces of data: the key data in the secure
element, the key metadata in internal storage, and the SE driver's
persistent data. Perform these actions in a transaction so that
recovery is possible if the action is interrupted midway.
Implement a transaction record that can be used for actions that
modify more than one piece of persistent data (whether in the
persistent storage or elsewhere such as in a secure element).
While performing a transaction, the transaction file is present in
storage. If the system starts with an ongoing transaction, it must
complete the transaction (not implemented yet).
In the generic message digest abstraction, instead of storing method
pointers in the per-algorithm data structure and using wrapper
functions as those methods, call the per-algorithm function directly.
This saves some code size (2336B -> 2043B for md with all algorithms
enabled on M0+ with gcc -Os). This should also make it easier to
optimize the case when a single algorithm is supported. In addition,
this is a very slight security improvement since it removes one
opportunity for a buffer overflow to directly turn into letting the
attacker overwrite a pointer to a function pointer.
This commit does not modify the documented API. However, it removes
the possibility for users to define their own hash implementations and
use them by building their own md_info.
Changing mbedtls_md_context to contain a md type identifier rather
than a pointer to an info structure would save a few more bytes and a
few more runtime memory accesses, but would be a major API break since
a lot of code uses `const mbedtls_md_info *` to keep track of which
hash is in use.
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.
memset has undefined behavior when either pointer can be NULL, which
is the case when it's the result of malloc/calloc with a size of 0.
The memset calls here are useless anyway since they come immediately
after calloc.
All modules using restartable ECC operations support passing `NULL`
as the restart context as a means to not use the feature.
The restart contexts for ECDSA and ECP are nested, and when calling
restartable ECP operations from restartable ECDSA operations, the
address of the ECP restart context to use is calculated by adding
the to the address of the ECDSA restart context the offset the of
the ECP restart context.
If the ECP restart context happens to not reside at offset `0`, this
leads to a non-`NULL` pointer being passed to restartable ECP
operations from restartable ECDSA-operations; those ECP operations
will hence assume that the pointer points to a valid ECP restart
address and likely run into a segmentation fault when trying to
dereference the non-NULL but close-to-NULL address.
The problem doesn't arise currently because luckily the ECP restart
context has offset 0 within the ECDSA restart context, but we should
not rely on it.
This commit fixes the passage from restartable ECDSA to restartable ECP
operations by propagating NULL as the restart context pointer.
Apart from being fragile, the previous version could also lead to
NULL pointer dereference failures in ASanDbg builds which dereferenced
the ECDSA restart context even though it's not needed to calculate the
address of the offset'ed ECP restart context.
All modules using restartable ECC operations support passing `NULL`
as the restart context as a means to not use the feature.
The restart contexts for ECDSA and ECP are nested, and when calling
restartable ECP operations from restartable ECDSA operations, the
address of the ECP restart context to use is calculated by adding
the to the address of the ECDSA restart context the offset the of
the ECP restart context.
If the ECP restart context happens to not reside at offset `0`, this
leads to a non-`NULL` pointer being passed to restartable ECP
operations from restartable ECDSA-operations; those ECP operations
will hence assume that the pointer points to a valid ECP restart
address and likely run into a segmentation fault when trying to
dereference the non-NULL but close-to-NULL address.
The problem doesn't arise currently because luckily the ECP restart
context has offset 0 within the ECDSA restart context, but we should
not rely on it.
This commit fixes the passage from restartable ECDSA to restartable ECP
operations by propagating NULL as the restart context pointer.
Apart from being fragile, the previous version could also lead to
NULL pointer dereference failures in ASanDbg builds which dereferenced
the ECDSA restart context even though it's not needed to calculate the
address of the offset'ed ECP restart context.
dummy
Replace some frequently-used macros by inline functions: instead of
calling MOD_{ADD,SUB,MUL} after the mbedtls_mpi_{add,sub,mul}_mpi,
call a function mbedtls_mpi_xxx_mod that does the same.
In the baremetal config, with "gcc -Os -mthumb -mcpu=cortex-m0plus",
ecp.o goes down from 13878 bytes to 12234.
No noticeable performance change for benchmarks on x86_64 with either
"gcc -O2" or "gcc -Os".
Make some functions non-static, to avoid Wunused function warnings. Make
a function scoped variable block scoped instead, to avoid Wunused
variable warnings in some configurations.
There is now a test that ensures all headers are included in the
cpp_dummy_build test, so we can't remove compat-1.3.h from the
cpp_dummy_build test until we remove compat-1.3.h.
This reverts commit 2b725ef727.
In configurations wanting an alternative ripemd160 implementation, We
were including the ordinary Mbed Crypto ripemd160.h instead of the
user-provided ripemd160_alt.h. Use the user-provided header instead.
To help the build system find the correct include files, paths starting
with "mbedtls/" or "psa/" must be used. Otherwise, you can run into
build failures like the following when building Mbed Crypto as a
submodule.
In file included from chachapoly.c:31:0:
../../include/mbedtls/chachapoly.h:43:10: fatal error: poly1305.h: No such file or directory
#include "poly1305.h"
^~~~~~~~~~~~
compilation terminated.
Includes for ALT implementations are not modified, as the alt headers
are provided by system integrators and not Mbed TLS or Mbed Crypto.
Most driver methods are not allowed to modify the persistent data, so
the driver context structure contains a const pointer to it. Pass a
non-const pointer to the persstent data to the driver methods that
need it: init, allocate, destroy.
Pass the driver context to all driver methods except the ones that
operate on an already-setup operation context.
Rename `p_context` arguments to `op_context` to avoid confusion
between contexts.
This slightly increases storage requirements, but works in more use
cases. In particular, it allows drivers to treat choose slot numbers
with a monotonic counter that is incremented each time a key is
created, without worrying about overflow in practice.
When creating a key with a lifetime that places it in a secure
element, retrieve the appropriate driver table entry.
This commit doesn't yet achieve behavior: so far the code only
retrieves the driver, it doesn't call the driver.
Instead of having one giant table containing all possible methods,
represent a driver's method table as a structure containing pointers
to substructures. This way a driver that doesn't implement a certain
class of operations can use NULL for this class as a whole instead of
storing NULL for each method.
Expose the type of an entry in the SE driver table as an opaque type
to other library modules. Soon, driver table entries will have state,
and callers will need to be able to access this state through
functions using this opaque type.
Provide functions to look up a driver by its lifetime and to retrieve
the method table from an entry.
