At the cost of about 0.5 kB of additional binary size, the internal
LibTomMath can be configured to include faster sqr routine to speed up DH
and RSA. This can be enabled with CONFIG_INTERNAL_LIBTOMMATH_FAST_SQR=y in
.config.
Add a cost of about 2.5 kB of additional cost, the internal LibTomMath can
be configured to include fast exptmod routine to speed up DH and RSA.
This can be enabled with CONFIG_INTERNAL_LIBTOMMATH_FAST_EXPTMOD=y in
.config.