login1: add support for session management

login1/dbus.go

@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-// Integration with the systemd logind API.  See http://www.freedesktop.org/wiki/Software/systemd/logind/
+// Package login1 provides integration with the systemd logind API.  See http://www.freedesktop.org/wiki/Software/systemd/logind/
 package login1
 
 import (
@@ -34,7 +34,7 @@ type Conn struct {
 	object dbus.BusObject
 }
 
-// New() establishes a connection to the system bus and authenticates.
+// New establishes a connection to the system bus and authenticates.
 func New() (*Conn, error) {
 	c := new(Conn)
 
@@ -74,6 +74,147 @@ func (c *Conn) initConnection() error {
 	return nil
 }
 
+// Session object definition.
+type Session struct {
+	ID   string
+	UID  uint32
+	User string
+	Seat string
+	Path dbus.ObjectPath
+}
+
+// User object definition.
+type User struct {
+	UID  uint32
+	Name string
+	Path dbus.ObjectPath
+}
+
+func (s Session) toInterface() []interface{} {
+	return []interface{}{s.ID, s.UID, s.User, s.Seat, s.Path}
+}
+
+func sessionFromInterfaces(session []interface{}) (*Session, error) {
+	if len(session) < 5 {
+		return nil, fmt.Errorf("invalid number of session fields: %d", len(session))
+	}
+	id, ok := session[0].(string)
+	if !ok {
+		return nil, fmt.Errorf("failed to typecast session field 0 to string")
+	}
+	uid, ok := session[1].(uint32)
+	if !ok {
+		return nil, fmt.Errorf("failed to typecast session field 1 to uint32")
+	}
+	user, ok := session[2].(string)
+	if !ok {
+		return nil, fmt.Errorf("failed to typecast session field 2 to string")
+	}
+	seat, ok := session[3].(string)
+	if !ok {
+		return nil, fmt.Errorf("failed to typecast session field 2 to string")
+	}
+	path, ok := session[4].(dbus.ObjectPath)
+	if !ok {
+		return nil, fmt.Errorf("failed to typecast session field 4 to ObjectPath")
+	}
+
+	ret := Session{ID: id, UID: uid, User: user, Seat: seat, Path: path}
+	return &ret, nil
+}
+
+func userFromInterfaces(user []interface{}) (*User, error) {
+	if len(user) < 3 {
+		return nil, fmt.Errorf("invalid number of user fields: %d", len(user))
+	}
+	uid, ok := user[0].(uint32)
+	if !ok {
+		return nil, fmt.Errorf("failed to typecast user field 0 to uint32")
+	}
+	name, ok := user[1].(string)
+	if !ok {
+		return nil, fmt.Errorf("failed to typecast session field 1 to string")
+	}
+	path, ok := user[2].(dbus.ObjectPath)
+	if !ok {
+		return nil, fmt.Errorf("failed to typecast user field 2 to ObjectPath")
+	}
+
+	ret := User{UID: uid, Name: name, Path: path}
+	return &ret, nil
+}
+
+// GetSession may be used to get the session object path for the session with the specified ID.
+func (c *Conn) GetSession(id string) (dbus.ObjectPath, error) {
+	var out interface{}
+	if err := c.object.Call(dbusInterface+".GetSession", 0, id).Store(&out); err != nil {
+		return "", err
+	}
+
+	ret, ok := out.(dbus.ObjectPath)
+	if !ok {
+		return "", fmt.Errorf("failed to typecast session to ObjectPath")
+	}
+
+	return ret, nil
+}
+
+// ListSessions returns an array with all current sessions.
+func (c *Conn) ListSessions() ([]Session, error) {
+	out := [][]interface{}{}
+	if err := c.object.Call(dbusInterface+".ListSessions", 0).Store(&out); err != nil {
+		return nil, err
+	}
+
+	ret := []Session{}
+	for _, el := range out {
+		session, err := sessionFromInterfaces(el)
+		if err != nil {
+			return nil, err
+		}
+		ret = append(ret, *session)
+	}
+	return ret, nil
+}
+
+// ListUsers returns an array with all currently logged in users.
+func (c *Conn) ListUsers() ([]User, error) {
+	out := [][]interface{}{}
+	if err := c.object.Call(dbusInterface+".ListUsers", 0).Store(&out); err != nil {
+		return nil, err
+	}
+
+	ret := []User{}
+	for _, el := range out {
+		user, err := userFromInterfaces(el)
+		if err != nil {
+			return nil, err
+		}
+		ret = append(ret, *user)
+	}
+	return ret, nil
+}
+
+// LockSession asks the session with the specified ID to activate the screen lock.
+func (c *Conn) LockSession(id string) {
+	c.object.Call(dbusInterface+".LockSession", 0, id)
+}
+
+// LockSessions asks all sessions to activate the screen locks. This may be used to lock any access to the machine in one action.
+func (c *Conn) LockSessions() {
+	c.object.Call(dbusInterface+".LockSessions", 0)
+}
+
+// TerminateSession forcibly terminate one specific session.
+func (c *Conn) TerminateSession(id string) {
+	c.object.Call(dbusInterface+".TerminateSession", 0, id)
+}
+
+// TerminateUser forcibly terminates all processes of a user.
+func (c *Conn) TerminateUser(uid uint32) {
+	c.object.Call(dbusInterface+".TerminateUser", 0, uid)
+}
+
 // Reboot asks logind for a reboot optionally asking for auth.
 func (c *Conn) Reboot(askForAuth bool) {
 	c.object.Call(dbusInterface+".Reboot", 0, askForAuth)

login1/dbus_test.go

@@ -15,6 +15,9 @@
 package login1
 
 import (
+	"fmt"
+	"os/user"
+	"regexp"
 	"testing"
 )
 
@@ -26,3 +29,61 @@ func TestNew(t *testing.T) {
 		t.Fatal(err)
 	}
 }
+
+func TestListSessions(t *testing.T) {
+	c, err := New()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	sessions, err := c.ListSessions()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if len(sessions) > 0 {
+		for _, s := range sessions {
+			lookup, err := user.Lookup(s.User)
+			if err != nil {
+				t.Fatal(err)
+			}
+			if fmt.Sprint(s.UID) != lookup.Uid {
+				t.Fatalf("expected uid '%d' but got '%s'", s.UID, lookup.Uid)
+			}
+
+			validPath := regexp.MustCompile(`/org/freedesktop/login1/session/_[0-9]+`)
+			if !validPath.MatchString(fmt.Sprint(s.Path)) {
+				t.Fatalf("invalid session path: %s", s.Path)
+			}
+		}
+	}
+}
+
+func TestListUsers(t *testing.T) {
+	c, err := New()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	users, err := c.ListUsers()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if len(users) > 0 {
+		for _, u := range users {
+			lookup, err := user.Lookup(u.Name)
+			if err != nil {
+				t.Fatal(err)
+			}
+			if fmt.Sprint(u.UID) != lookup.Uid {
+				t.Fatalf("expected uid '%d' but got '%s'", u.UID, lookup.Uid)
+			}
+
+			validPath := regexp.MustCompile(`/org/freedesktop/login1/user/_[0-9]+`)
+			if !validPath.MatchString(fmt.Sprint(u.Path)) {
+				t.Fatalf("invalid user path: %s", u.Path)
+			}
+		}
+	}
+}