1 files changed, 36 insertions, 18 deletions
diff --git a/pkgs/build-support/cc-wrapper/add-hardening.sh b/pkgs/build-support/cc-wrapper/add-hardening.sh
index b98833b3513b..b0e39e455ffc 100644
--- a/pkgs/build-support/cc-wrapper/add-hardening.sh
+++ b/pkgs/build-support/cc-wrapper/add-hardening.sh
@@ -1,57 +1,75 @@
 hardeningFlags=(fortify stackprotector pic strictoverflow format relro bindnow)
-hardeningFlags+=("${hardeningEnable[@]}")
+# Intentionally word-split in case 'hardeningEnable' is defined in
+# Nix. Also, our bootstrap tools version of bash is old enough that
+# undefined arrays trip `set -u`.
+if [[ -v hardeningEnable[@] ]]; then
+  hardeningFlags+=(${hardeningEnable[@]})
+fi
 hardeningCFlags=()
 hardeningLDFlags=()
-hardeningDisable=${hardeningDisable:-""}
 
-hardeningDisable+=" @hardening_unsupported_flags@"
+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 "$NIX_DEBUG" ]]; then echo HARDENING: Value of '$hardeningDisable': $hardeningDisable >&2; fi
+if (( "${NIX_DEBUG:-0}" >= 1 )); then
+  printf 'HARDENING: disabled flags:' >&2
+  (( "${#hardeningDisableMap[@]}" )) && printf ' %q' "${!hardeningDisableMap[@]}" >&2
+  echo >&2
+fi
 
-if [[ ! $hardeningDisable =~ "all" ]]; then
-  if [[ -n "$NIX_DEBUG" ]]; then echo 'HARDENING: Is active (not completely disabled with "all" flag)' >&2; fi
+if [[ -z "${hardeningDisableMap[all]:-}" ]]; then
+  if (( "${NIX_DEBUG:-0}" >= 1 )); then
+    echo 'HARDENING: Is active (not completely disabled with "all" flag)' >&2;
+  fi
   for flag in "${hardeningFlags[@]}"
   do
-    if [[ ! "${hardeningDisable}" =~ "$flag" ]]; then
+    if [[ -z "${hardeningDisableMap[$flag]:-}" ]]; then
       case $flag in
         fortify)
-          if [[ -n "$NIX_DEBUG" ]]; then echo HARDENING: enabling fortify >&2; fi
+          if (( "${NIX_DEBUG:-0}" >= 1 )); then echo HARDENING: enabling fortify >&2; fi
           hardeningCFlags+=('-O2' '-D_FORTIFY_SOURCE=2')
           ;;
         stackprotector)
-          if [[ -n "$NIX_DEBUG" ]]; then echo HARDENING: enabling stackprotector >&2; fi
-          hardeningCFlags+=('-fstack-protector-strong' '--param ssp-buffer-size=4')
+          if (( "${NIX_DEBUG:-0}" >= 1 )); then echo HARDENING: enabling stackprotector >&2; fi
+          hardeningCFlags+=('-fstack-protector-strong' '--param' 'ssp-buffer-size=4')
           ;;
         pie)
-          if [[ -n "$NIX_DEBUG" ]]; then echo HARDENING: enabling CFlags -fPIE >&2; fi
+          if (( "${NIX_DEBUG:-0}" >= 1 )); then echo HARDENING: enabling CFlags -fPIE >&2; fi
           hardeningCFlags+=('-fPIE')
           if [[ ! ("$*" =~ " -shared " || "$*" =~ " -static ") ]]; then
-            if [[ -n "$NIX_DEBUG" ]]; then echo HARDENING: enabling LDFlags -pie >&2; fi
+            if (( "${NIX_DEBUG:-0}" >= 1 )); then echo HARDENING: enabling LDFlags -pie >&2; fi
+            hardeningCFlags+=('-pie')
             hardeningLDFlags+=('-pie')
           fi
           ;;
         pic)
-          if [[ -n "$NIX_DEBUG" ]]; then echo HARDENING: enabling pic >&2; fi
+          if (( "${NIX_DEBUG:-0}" >= 1 )); then echo HARDENING: enabling pic >&2; fi
           hardeningCFlags+=('-fPIC')
           ;;
         strictoverflow)
-          if [[ -n "$NIX_DEBUG" ]]; then echo HARDENING: enabling strictoverflow >&2; fi
+          if (( "${NIX_DEBUG:-0}" >= 1 )); then echo HARDENING: enabling strictoverflow >&2; fi
           hardeningCFlags+=('-fno-strict-overflow')
           ;;
         format)
-          if [[ -n "$NIX_DEBUG" ]]; then echo HARDENING: enabling format >&2; fi
+          if (( "${NIX_DEBUG:-0}" >= 1 )); then echo HARDENING: enabling format >&2; fi
           hardeningCFlags+=('-Wformat' '-Wformat-security' '-Werror=format-security')
           ;;
         relro)
-          if [[ -n "$NIX_DEBUG" ]]; then echo HARDENING: enabling relro >&2; fi
+          if (( "${NIX_DEBUG:-0}" >= 1 )); then echo HARDENING: enabling relro >&2; fi
           hardeningLDFlags+=('-z' 'relro')
           ;;
         bindnow)
-          if [[ -n "$NIX_DEBUG" ]]; then echo HARDENING: enabling bindnow >&2; fi
+          if (( "${NIX_DEBUG:-0}" >= 1 )); then echo HARDENING: enabling bindnow >&2; fi
           hardeningLDFlags+=('-z' 'now')
           ;;
         *)
-          echo "Hardening flag unknown: $flag" >&2
+          # Ignore unsupported. Checked in Nix that at least *some*
+          # tool supports each flag.
           ;;
       esac
     fi