ecp_select_comb() did previously not set the Z coordinate of the target point.
Instead, callers would either set it explicitly or leave it uninitialized,
relying on the (only partly upheld) convention that sometimes an uninitialized
Z value represents 1.
This commit modifies ecp_select_comb() to always set the Z coordinate to 1.
This comes at the cost of memory for a single coordinate, which seems worth
it for the increased robustness.
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
This improves readibility and prepares for further changes
like the introduction of a single double-width temporary for
ECP arithmetic.
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
`ecp_add_mixed()` and `ecp_double_jac()` are the core subroutines
for elliptic curve arithmetic, and as such crucial for the performance
of ECP primitives like ECDHE and ECDSA.
This commit provides a very slight simplification and performance and
memory usage improvement to `ecp_add_mixed()` by removing the use of
three temporary MPIs used for coordinate calculations.
Where those variables were used, the code now writes directly to the
coordinate MPIs of the target elliptic curve point.
This is a valid change even if there is aliasing between input and
output, since at the time any of the coordinate MPIs in question is
written, the corresponding coordinates of both inputs are no longer
read.
(The analogous change in `ecp_double_jac()` can not be made since
this property does not hold for `ecp_double_jac()`.)
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
Change 'tranlation' -> 'translation' in the name of a
method in `scripts/generate_ssl_debug_headers.py`.
Signed-off-by: David Horstmann <david.horstmann@arm.com>
Having an automatically generated header file makes it harder to have
working build scripts. The content of ssl_debug_helpers_generated.h isn't
likely to change often, so we can update it manually.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Running `generate_ssl_debug_helpers.py` generates both
`ssl_debug_helpers_generated.c` and `ssl_debug_helpers_generated.h`.
List the `.h` file as well as the `.c` file in `check-generated-files.sh` so
that `check-generated-files.sh -u` will complain if it isn't up to date.
List it in `Makefile` and `CMakeLists.txt` so that parallel builds know when
to wait until the `.h` file is present. In `Makefile`, declare the `.c` file
as depending on the `.h` file for order. This way, a dependency for either
will wait until the `.h` file is present, and since the `.h` file is
generated after the `.c` file, this guarantees that the `.c` file is
present.
This fixes random failures of `make -j` from a fresh checkout.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Zeroize temporary buffers used to sanity-check the signature.
If there is an error, overwrite the tentative signature in the output
buffer.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
