HardenedBSD/tools/build/options/WITH_BRANCH_PROTECTION

Build with branch protection enabled.
On arm64 enable the use of pointer authentication and
branch target identification instructions on arm64.
These can be used to help mitigate some exploit techniques.
arm64: Allow userspace to be built with PAC and BTI Add the WITH/WITHOUT_BRANCH_PROTECTION build flags. This can be used to enable the use of pointer authentication (FEAT_PAuth) and branch target identification (FEAT_BTI) in userspace. The kernel already handles both of these is userspace, we just need to enable it. Leave disabled for a short period for this to settle before enabling. Reviewed by: emaste Sponsored by: Arm Ltd Differential Revision: https://reviews.freebsd.org/D42596 2024-05-22 17:54:32 +02:00			`Build with branch protection enabled.`
			`On arm64 enable the use of pointer authentication and`
			`branch target identification instructions on arm64.`
			`These can be used to help mitigate some exploit techniques.`