fix(release): enforce Apple hardened runtime

apple/scripts/build-dmg.sh

@@ -105,6 +105,12 @@ ACTUAL_BUILD="$(/usr/libexec/PlistBuddy -c 'Print :CFBundleVersion' \
 	exit 1
 }
 
+echo "==> Enforcing hardened-runtime signature"
+"$SCRIPT_DIR/sign-exported-app.sh" \
+	"$APP" \
+	"$DEVELOPER_ID_APP" \
+	"$APPLE_DIR/VniDrop/Resources/VniDropDirect.entitlements"
+
 # --- Build the DMG -----------------------------------------------------------
 DMG="$DIST_DIR/$APP_NAME-$VERSION.dmg"
 rm -f "$DMG"

apple/scripts/sign-exported-app.sh

@@ -0,0 +1,42 @@
+#!/usr/bin/env bash
+
+set -euo pipefail
+
+if [[ $# -ne 3 ]]; then
+	printf 'Usage: %s <app-bundle> <signing-identity> <entitlements>\n' "$0" >&2
+	exit 2
+fi
+
+app=$1
+signing_identity=$2
+entitlements=$3
+
+[[ -d $app ]] || {
+	printf 'error: exported app bundle does not exist: %s\n' "$app" >&2
+	exit 1
+}
+[[ -n $signing_identity ]] || {
+	printf 'error: signing identity is empty\n' >&2
+	exit 1
+}
+[[ -f $entitlements ]] || {
+	printf 'error: entitlements file does not exist: %s\n' "$entitlements" >&2
+	exit 1
+}
+
+codesign \
+	--force \
+	--sign "$signing_identity" \
+	--options runtime \
+	--timestamp \
+	--entitlements "$entitlements" \
+	"$app"
+codesign --verify --deep --strict --verbose=2 "$app"
+
+signature_details="$(codesign --display --verbose=4 "$app" 2>&1)"
+printf '%s\n' "$signature_details"
+printf '%s\n' "$signature_details" |
+	grep -Eq 'flags=.*\(runtime([^)]*)?\)' || {
+		printf 'error: exported app signature does not enable the hardened runtime\n' >&2
+		exit 1
+	}

apple/scripts/tests/test-sign-exported-app.sh

@@ -0,0 +1,78 @@
+#!/usr/bin/env bash
+
+set -euo pipefail
+
+script_dir="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+sign_exported_app="$script_dir/../sign-exported-app.sh"
+scratch="$(mktemp -d "${TMPDIR:-/tmp}/vnidrop-codesign-test.XXXXXX")"
+trap 'rm -rf "$scratch"' EXIT
+
+mkdir -p "$scratch/bin" "$scratch/VniDrop.app/Contents/MacOS"
+app="$scratch/VniDrop.app"
+entitlements="$scratch/VniDropDirect.entitlements"
+calls="$scratch/calls.txt"
+printf '<plist><dict/></plist>\n' > "$entitlements"
+printf 'binary\n' > "$app/Contents/MacOS/VniDrop"
+
+cat > "$scratch/bin/codesign" <<'SCRIPT'
+#!/usr/bin/env bash
+set -euo pipefail
+
+printf '%s\n' "$*" >> "$FAKE_CODESIGN_CALLS"
+case " $* " in
+	*" --display "*)
+		if [[ ${FAKE_CODESIGN_MODE:-runtime} == missing-runtime ]]; then
+			printf '%s\n' \
+				'CodeDirectory v=20500 size=123 flags=0x0(none) hashes=1+0 location=embedded' \
+				>&2
+		else
+			printf '%s\n' \
+				'CodeDirectory v=20500 size=123 flags=0x10000(runtime) hashes=1+0 location=embedded' \
+				>&2
+		fi
+		;;
+	*" --verify "*)
+		if [[ ${FAKE_CODESIGN_MODE:-runtime} == verify-error ]]; then
+			printf '%s\n' 'invalid signature' >&2
+			exit 1
+		fi
+		;;
+esac
+SCRIPT
+chmod +x "$scratch/bin/codesign"
+
+PATH="$scratch/bin:$PATH" \
+	FAKE_CODESIGN_CALLS="$calls" \
+	"$sign_exported_app" \
+	"$app" \
+	'Developer ID Application: Example (ABCDEFGHIJ)' \
+	"$entitlements" >/dev/null
+grep -F -- \
+	'--force --sign Developer ID Application: Example (ABCDEFGHIJ) --options runtime --timestamp --entitlements' \
+	"$calls" >/dev/null
+grep -F -- '--verify --deep --strict --verbose=2' "$calls" >/dev/null
+grep -F -- '--display --verbose=4' "$calls" >/dev/null
+
+if PATH="$scratch/bin:$PATH" \
+	FAKE_CODESIGN_CALLS="$calls" \
+	FAKE_CODESIGN_MODE=missing-runtime \
+	"$sign_exported_app" \
+	"$app" \
+	'Developer ID Application: Example (ABCDEFGHIJ)' \
+	"$entitlements" >/dev/null 2>&1; then
+	printf 'A signature without the hardened runtime must fail\n' >&2
+	exit 1
+fi
+
+if PATH="$scratch/bin:$PATH" \
+	FAKE_CODESIGN_CALLS="$calls" \
+	FAKE_CODESIGN_MODE=verify-error \
+	"$sign_exported_app" \
+	"$app" \
+	'Developer ID Application: Example (ABCDEFGHIJ)' \
+	"$entitlements" >/dev/null 2>&1; then
+	printf 'Signature verification errors must fail\n' >&2
+	exit 1
+fi
+
+printf 'Exported app signing tests passed.\n'