fix: switch the daemon on after moving over from plasma-face-unlock

src/lib/migrate.sh

@@ -48,7 +48,7 @@ _fu_pam_drop_old() {
 # The system settings, the faces, sudo and admin prompts and the daemon's
 # socket, as plasma-face-unlock left them.
 fu_migrate_system() {
-	local service link
+	local service link used=0
 
 	if [[ -d $FU_OLD_SYSDIR ]]; then
 		if [[ -f $FU_OLD_SYSDIR/config && ! -e $FU_SYSCONFIG ]]; then
@@ -63,6 +63,7 @@ fu_migrate_system() {
 			install -d -m 0700 "$FU_STATEDIR" || return 1
 			rm -rf -- "$FU_STATEDIR/users"
 			mv -- "$FU_OLD_STATEDIR/users" "$FU_STATEDIR/users" || return 1
+			used=1
 		fi
 		rm -rf -- "$FU_OLD_STATEDIR"
 	fi
@@ -70,12 +71,19 @@ fu_migrate_system() {
 	for service in "${FU_PAM_SERVICES[@]}"; do
 		_fu_pam_has_old "$service" || continue
 		_fu_pam_drop_old "$service" && fu_pam_enable "$service"
+		used=1
 	done
 
 	link="$(_fu_old_socket_link)"
 	if [[ -L $link ]]; then
 		systemctl disable --now "${FU_OLD_NAME}d.socket" > /dev/null 2>&1 || true
 		rm -f -- "$link"
+		used=1
+	fi
+
+	# The old package switches its socket off when it is removed, mostly before
+	# this runs. So its faces and PAM lines count as the sign that it was used.
+	if (( used )); then
 		systemctl enable --now "$FU_UNIT_SOCKET" > /dev/null 2>&1 || true
 	fi
 	return 0

tests/test_pam.sh

@@ -166,6 +166,10 @@ FU_SYSCONFIG="$tmp/new-etc/config"
 FU_SYSTEMD_ETC="$tmp/systemd"
 old_module=/usr/lib/security/pam_plasma_face_unlock.so
 
+# systemctl is only written down.
+# shellcheck disable=SC2329  # called by fu_migrate_system and fu_migrate_user
+systemctl() { printf '%s\n' "$*" >> "$tmp/systemctl"; }
+
 # What plasma-face-unlock wrote is what this writes, under the old name.
 make_old() {
 	sed -i -e "s|^$FU_PAM_MARK\$|$FU_OLD_PAM_MARK|" -e "s|$FU_PAM_WRAPPER_MARK|$FU_OLD_PAM_WRAPPER_MARK|" \
@@ -199,19 +203,21 @@ mkdir -p "$FU_OLD_SYSDIR" "$FU_OLD_STATEDIR/users"
 echo 'Liveness=heavy' > "$FU_OLD_SYSDIR/config"
 echo '{}' > "$FU_OLD_STATEDIR/users/1000.json"
 check "old settings and faces are found" 'fu_migrate_pending'
+: > "$tmp/systemctl"
 fu_migrate_system
 check "the system settings moved" '[[ $(cat "$FU_SYSCONFIG") == Liveness=heavy && ! -e $FU_OLD_SYSDIR ]]'
 check "the faces moved" '[[ $(cat "$FU_STATEDIR/users/1000.json") == "{}" && ! -e $FU_OLD_STATEDIR ]]'
+check "the socket is on, although the old package switched its own off" 'grep -qx "enable --now face-unlockd.socket" "$tmp/systemctl"'
 
 mkdir -p "$FU_OLD_STATEDIR/users"
 echo old > "$FU_OLD_STATEDIR/users/1000.json"
+: > "$tmp/systemctl"
 fu_migrate_system
 check "faces set up under the new name win" '[[ $(cat "$FU_STATEDIR/users/1000.json") == "{}" && ! -e $FU_OLD_STATEDIR ]]'
+check "and the socket is left as it is" '[[ ! -s $tmp/systemctl ]]'
 check "nothing is left over at the end" '! fu_migrate_pending'
 
-# This user's side, with systemctl only written down.
-# shellcheck disable=SC2329  # called by fu_migrate_user
-systemctl() { printf '%s\n' "$*" >> "$tmp/systemctl"; }
+# This user's side.
 FU_XDG_CONFIG="$tmp/home-config"
 FU_CONFDIR="$FU_XDG_CONFIG/face-unlock"
 mkdir -p "$FU_XDG_CONFIG/plasma-face-unlock" "$FU_XDG_CONFIG/systemd/user/graphical-session.target.wants"