nixpkgs/pkgs/build-support/binutils-wrapper/add-hardening.sh
John Ericson 40e9b2a7e6 binutils-wrapper: Init
Factor a binutils wrapper out of cc-wrapper. While only LD is wrapped,
the setup hook defines environment variables on behalf of other
utilites.
2017-09-01 11:44:55 -04:00

54 lines
1.7 KiB
Bash

hardeningFlags=(relro bindnow)
# Intentionally word-split in case 'hardeningEnable' is defined in
# Nix. Also, our bootstrap tools version of bash is old enough that
# undefined arrays trip `set -u`.
if [[ -v hardeningEnable[@] ]]; then
hardeningFlags+=(${hardeningEnable[@]})
fi
hardeningLDFlags=()
declare -A hardeningDisableMap
# Intentionally word-split in case 'hardeningDisable' is defined in Nix.
for flag in ${hardeningDisable[@]:-IGNORED_KEY} @hardening_unsupported_flags@
do
hardeningDisableMap[$flag]=1
done
if [[ -n "${NIX_DEBUG:-}" ]]; then
printf 'HARDENING: disabled flags:' >&2
(( "${#hardeningDisableMap[@]}" )) && printf ' %q' "${!hardeningDisableMap[@]}" >&2
echo >&2
fi
if [[ -z "${hardeningDisableMap[all]:-}" ]]; then
if [[ -n "${NIX_DEBUG:-}" ]]; then
echo 'HARDENING: Is active (not completely disabled with "all" flag)' >&2;
fi
for flag in "${hardeningFlags[@]}"
do
if [[ -z "${hardeningDisableMap[$flag]:-}" ]]; then
case $flag in
pie)
if [[ ! ("$*" =~ " -shared " || "$*" =~ " -static ") ]]; then
if [[ -n "${NIX_DEBUG:-}" ]]; then echo HARDENING: enabling LDFlags -pie >&2; fi
hardeningLDFlags+=('-pie')
fi
;;
relro)
if [[ -n "${NIX_DEBUG:-}" ]]; then echo HARDENING: enabling relro >&2; fi
hardeningLDFlags+=('-z' 'relro')
;;
bindnow)
if [[ -n "${NIX_DEBUG:-}" ]]; then echo HARDENING: enabling bindnow >&2; fi
hardeningLDFlags+=('-z' 'now')
;;
*)
# Ignore unsupported. Checked in Nix that at least *some*
# tool supports each flag.
;;
esac
fi
done
fi