This patch updates the `mbedtls_mpi_mod_modulus_setup/free()`
methods to precalculate mm and rr(Montgomery const squared) during
setup and zeroize it during free.
A static `set_mont_const_square()` is added to manage the memory allocation
and parameter checking before invoking the
`mbedtls_mpi_core_get_mont_r2_unsafe()`
Signed-off-by: Minos Galanakis <minos.galanakis@arm.com>
We used to include platform.h only when MBEDTLS_PLATFORM_C was enabled, and
to define ad hoc replacements for mbedtls_xxx functions on a case-by-case
basis when MBEDTLS_PLATFORM_C was disabled. The only reason for this
complication was to allow building individual source modules without copying
platform.h. This is not something we support or recommend anymore, so get
rid of the complication: include platform.h unconditionally.
There should be no change in behavior since just including the header should
not change the behavior of a program.
This commit replaces most occurrences of conditional inclusion of
platform.h, using the following code:
```
perl -i -0777 -pe 's!#if.*\n#include "mbedtls/platform.h"\n(#else.*\n(#define (mbedtls|MBEDTLS)_.*\n|#include <(stdarg|stddef|stdio|stdlib|string|time)\.h>\n)*)?#endif.*!#include "mbedtls/platform.h"!mg' $(git grep -l '#include "mbedtls/platform.h"')
```
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Numbers:
- A, B for mbedtls_mpi_uint* operands
- a, b for mbedtls_mpi_uint operands
- X or x for result
- HAC references where applicable
Lengths:
- Reserve size or length for length/size in bytes or byte buffers.
- For length of mbedtls_mpi_uint* buffers use limbs
- Length parameters are qualified if possible (eg. input_length or
a_limbs)
Setup functions:
- The parameters match the corresponding structure member's name
- The structure to set up is a standard lower case name even if in other
functions different naming conventions would apply
Scope of changes/conventions:
- bignum_core
- bignum_mod
- bignum_mod_raw
Signed-off-by: Janos Follath <janos.follath@arm.com>
The modulus value won't change during normal operations, make this clear
in the struct and the function signatures.
This won't prevent the caller from modifying the passed buffer, but
might give a hint and reinforces the message of the documentation.
Signed-off-by: Janos Follath <janos.follath@arm.com>
A null pointer dereference, or null pointer plus small offset, is a
clean runtime error in most environments. So it's not particularly
useful to protect against this.
While at it make a null pointer check that is actually necessary more
robust.
Signed-off-by: Janos Follath <janos.follath@arm.com>
- Made use of enums in struct and function declaration
- All enums are handled by switch case now
- If the switch does nothing on default, omit the default case to make
compiler warnings more powerful
- The two enums are now disjoint and the value 1 is skipped to make
mistakes easier to detect
Signed-off-by: Janos Follath <janos.follath@arm.com>
Extract functions declared in bignum_mod.h into a source file with a
matching name.
We are doing this because:
- This is a general best practice/convention
- We hope that this will make resolving merge conflicts in the future
easier
- Having them in a unified source file is a premature optimisation at
this point
This makes library/bignum_new.c empty and therefore it is deleted.
Signed-off-by: Janos Follath <janos.follath@arm.com>