final: refactor for removal of system package and reduction of interactions to state package

State query command has been moved to main where it belongs, "system" information are now fetched in app.New and stored in *App with accessors for relevant values. Exit (cleanup-related) functions are separated into its dedicated "final" package.

Signed-off-by: Ophestra Umiker <cat@ophivana.moe>

internal/app/dbus.go

@@ -3,6 +3,7 @@ package app
 import (
 	"errors"
 	"fmt"
+	"git.ophivana.moe/cat/fortify/internal/final"
 	"os"
 	"path"
 	"strconv"
@@ -10,7 +11,6 @@ import (
 	"git.ophivana.moe/cat/fortify/dbus"
 	"git.ophivana.moe/cat/fortify/internal/acl"
 	"git.ophivana.moe/cat/fortify/internal/state"
-	"git.ophivana.moe/cat/fortify/internal/system"
 	"git.ophivana.moe/cat/fortify/internal/util"
 	"git.ophivana.moe/cat/fortify/internal/verbose"
 )
@@ -32,7 +32,7 @@ func (a *App) ShareDBus(dse, dsg *dbus.Config, log bool) {
 	var binPath string
 	var sessionBus, systemBus [2]string
 
-	target := path.Join(system.V.Share, strconv.Itoa(os.Getpid()))
+	target := path.Join(a.sharePath, strconv.Itoa(os.Getpid()))
 	sessionBus[1] = target + ".bus"
 	systemBus[1] = target + ".system-bus"
 	dbusAddress = [2]string{
@@ -41,7 +41,7 @@ func (a *App) ShareDBus(dse, dsg *dbus.Config, log bool) {
 	}
 
 	if b, ok := util.Which("xdg-dbus-proxy"); !ok {
-		state.Fatal("D-Bus: Did not find 'xdg-dbus-proxy' in PATH")
+		final.Fatal("D-Bus: Did not find 'xdg-dbus-proxy' in PATH")
 	} else {
 		binPath = b
 	}
@@ -69,7 +69,7 @@ func (a *App) ShareDBus(dse, dsg *dbus.Config, log bool) {
 		verbose.Println("D-Bus: sealing system proxy", dsg.Args(systemBus))
 	}
 	if err := p.Seal(dse, dsg); err != nil {
-		state.Fatal("D-Bus: invalid config when sealing proxy,", err)
+		final.Fatal("D-Bus: invalid config when sealing proxy,", err)
 	}
 
 	ready := make(chan bool, 1)
@@ -80,7 +80,7 @@ func (a *App) ShareDBus(dse, dsg *dbus.Config, log bool) {
 		verbose.Printf("Starting system bus proxy '%s' for address '%s'\n", dbusAddress[1], systemBus[0])
 	}
 	if err := p.Start(&ready); err != nil {
-		state.Fatal("D-Bus: error starting proxy,", err)
+		final.Fatal("D-Bus: error starting proxy,", err)
 	}
 	verbose.Println("D-Bus proxy launch:", p)
 
@@ -97,24 +97,24 @@ func (a *App) ShareDBus(dse, dsg *dbus.Config, log bool) {
 	}()
 
 	// register early to enable Fatal cleanup
-	state.RegisterDBus(p, &done)
+	final.RegisterDBus(p, &done)
 
 	if !<-ready {
-		state.Fatal("D-Bus: proxy did not start correctly")
+		final.Fatal("D-Bus: proxy did not start correctly")
 	}
 
 	a.AppendEnv(dbusSessionBusAddress, dbusAddress[0])
 	if err := acl.UpdatePerm(sessionBus[1], a.UID(), acl.Read, acl.Write); err != nil {
-		state.Fatal(fmt.Sprintf("Error preparing D-Bus session proxy '%s':", dbusAddress[0]), err)
+		final.Fatal(fmt.Sprintf("Error preparing D-Bus session proxy '%s':", dbusAddress[0]), err)
 	} else {
-		state.RegisterRevertPath(sessionBus[1])
+		final.RegisterRevertPath(sessionBus[1])
 	}
 	if dsg != nil {
 		a.AppendEnv(dbusSystemBusAddress, dbusAddress[1])
 		if err := acl.UpdatePerm(systemBus[1], a.UID(), acl.Read, acl.Write); err != nil {
-			state.Fatal(fmt.Sprintf("Error preparing D-Bus system proxy '%s':", dbusAddress[1]), err)
+			final.Fatal(fmt.Sprintf("Error preparing D-Bus system proxy '%s':", dbusAddress[1]), err)
 		} else {
-			state.RegisterRevertPath(systemBus[1])
+			final.RegisterRevertPath(systemBus[1])
 		}
 	}
 	verbose.Printf("Session bus proxy '%s' for address '%s' configured\n", dbusAddress[0], sessionBus[0])

internal/app/ensure.go

@@ -0,0 +1,62 @@
+package app
+
+import (
+	"errors"
+	"fmt"
+	"git.ophivana.moe/cat/fortify/internal/acl"
+	"git.ophivana.moe/cat/fortify/internal/final"
+	"git.ophivana.moe/cat/fortify/internal/verbose"
+	"io/fs"
+	"os"
+	"path"
+)
+
+func (a *App) EnsureRunDir() {
+	if err := os.Mkdir(a.runDirPath, 0700); err != nil && !errors.Is(err, fs.ErrExist) {
+		final.Fatal("Error creating runtime directory:", err)
+	}
+}
+
+func (a *App) EnsureRuntime() {
+	if s, err := os.Stat(a.runtimePath); err != nil {
+		if errors.Is(err, fs.ErrNotExist) {
+			final.Fatal("Runtime directory does not exist")
+		}
+		final.Fatal("Error accessing runtime directory:", err)
+	} else if !s.IsDir() {
+		final.Fatal(fmt.Sprintf("Path '%s' is not a directory", a.runtimePath))
+	} else {
+		if err = acl.UpdatePerm(a.runtimePath, a.UID(), acl.Execute); err != nil {
+			final.Fatal("Error preparing runtime directory:", err)
+		} else {
+			final.RegisterRevertPath(a.runtimePath)
+		}
+		verbose.Printf("Runtime data dir '%s' configured\n", a.runtimePath)
+	}
+}
+
+func (a *App) EnsureShare() {
+	// acl is unnecessary as this directory is world executable
+	if err := os.Mkdir(a.sharePath, 0701); err != nil && !errors.Is(err, fs.ErrExist) {
+		final.Fatal("Error creating shared directory:", err)
+	}
+
+	// workaround for launch method sudo
+	if a.LaunchOption() == LaunchMethodSudo {
+		// ensure child runtime directory (e.g. `/tmp/fortify.%d/%d.share`)
+		cr := path.Join(a.sharePath, a.Uid+".share")
+		if err := os.Mkdir(cr, 0700); err != nil && !errors.Is(err, fs.ErrExist) {
+			final.Fatal("Error creating child runtime directory:", err)
+		} else {
+			if err = acl.UpdatePerm(cr, a.UID(), acl.Read, acl.Write, acl.Execute); err != nil {
+				final.Fatal("Error preparing child runtime directory:", err)
+			} else {
+				final.RegisterRevertPath(cr)
+			}
+			a.AppendEnv("XDG_RUNTIME_DIR", cr)
+			a.AppendEnv("XDG_SESSION_CLASS", "user")
+			a.AppendEnv("XDG_SESSION_TYPE", "tty")
+			verbose.Printf("Child runtime data dir '%s' configured\n", cr)
+		}
+	}
+}

internal/app/launch.go

@@ -5,11 +5,11 @@ import (
 	"encoding/base64"
 	"encoding/gob"
 	"fmt"
+	"git.ophivana.moe/cat/fortify/internal/final"
 	"os"
 	"strings"
 	"syscall"
 
-	"git.ophivana.moe/cat/fortify/internal/state"
 	"git.ophivana.moe/cat/fortify/internal/util"
 )
 
@@ -20,7 +20,7 @@ func (a *App) launcherPayloadEnv() string {
 	enc := base64.NewEncoder(base64.StdEncoding, r)
 
 	if err := gob.NewEncoder(enc).Encode(a.command); err != nil {
-		state.Fatal("Error encoding launcher payload:", err)
+		final.Fatal("Error encoding launcher payload:", err)
 	}
 
 	_ = enc.Close()

internal/app/pulse.go

@@ -3,13 +3,13 @@ package app
 import (
 	"errors"
 	"fmt"
+	"git.ophivana.moe/cat/fortify/internal/final"
 	"io/fs"
 	"os"
 	"path"
 
 	"git.ophivana.moe/cat/fortify/internal/acl"
 	"git.ophivana.moe/cat/fortify/internal/state"
-	"git.ophivana.moe/cat/fortify/internal/system"
 	"git.ophivana.moe/cat/fortify/internal/util"
 	"git.ophivana.moe/cat/fortify/internal/verbose"
 )
@@ -18,46 +18,46 @@ func (a *App) SharePulse() {
 	a.setEnablement(state.EnablePulse)
 
 	// ensure PulseAudio directory ACL (e.g. `/run/user/%d/pulse`)
-	pulse := path.Join(system.V.Runtime, "pulse")
+	pulse := path.Join(a.runtimePath, "pulse")
 	pulseS := path.Join(pulse, "native")
 	if s, err := os.Stat(pulse); err != nil {
 		if !errors.Is(err, fs.ErrNotExist) {
-			state.Fatal("Error accessing PulseAudio directory:", err)
+			final.Fatal("Error accessing PulseAudio directory:", err)
 		}
-		state.Fatal(fmt.Sprintf("PulseAudio dir '%s' not found", pulse))
+		final.Fatal(fmt.Sprintf("PulseAudio dir '%s' not found", pulse))
 	} else {
 		// add environment variable for new process
 		a.AppendEnv(util.PulseServer, "unix:"+pulseS)
 		if err = acl.UpdatePerm(pulse, a.UID(), acl.Execute); err != nil {
-			state.Fatal("Error preparing PulseAudio:", err)
+			final.Fatal("Error preparing PulseAudio:", err)
 		} else {
-			state.RegisterRevertPath(pulse)
+			final.RegisterRevertPath(pulse)
 		}
 
 		// ensure PulseAudio socket permission (e.g. `/run/user/%d/pulse/native`)
 		if s, err = os.Stat(pulseS); err != nil {
 			if errors.Is(err, fs.ErrNotExist) {
-				state.Fatal("PulseAudio directory found but socket does not exist")
+				final.Fatal("PulseAudio directory found but socket does not exist")
 			}
-			state.Fatal("Error accessing PulseAudio socket:", err)
+			final.Fatal("Error accessing PulseAudio socket:", err)
 		} else {
 			if m := s.Mode(); m&0o006 != 0o006 {
-				state.Fatal(fmt.Sprintf("Unexpected permissions on '%s':", pulseS), m)
+				final.Fatal(fmt.Sprintf("Unexpected permissions on '%s':", pulseS), m)
 			}
 		}
 
 		// Publish current user's pulse-cookie for target user
 		pulseCookieSource := util.DiscoverPulseCookie()
-		pulseCookieFinal := path.Join(system.V.Share, "pulse-cookie")
+		pulseCookieFinal := path.Join(a.sharePath, "pulse-cookie")
 		a.AppendEnv(util.PulseCookie, pulseCookieFinal)
 		verbose.Printf("Publishing PulseAudio cookie '%s' to '%s'\n", pulseCookieSource, pulseCookieFinal)
 		if err = util.CopyFile(pulseCookieFinal, pulseCookieSource); err != nil {
-			state.Fatal("Error copying PulseAudio cookie:", err)
+			final.Fatal("Error copying PulseAudio cookie:", err)
 		}
 		if err = acl.UpdatePerm(pulseCookieFinal, a.UID(), acl.Read); err != nil {
-			state.Fatal("Error publishing PulseAudio cookie:", err)
+			final.Fatal("Error publishing PulseAudio cookie:", err)
 		} else {
-			state.RegisterRevertPath(pulseCookieFinal)
+			final.RegisterRevertPath(pulseCookieFinal)
 		}
 
 		verbose.Printf("PulseAudio dir '%s' configured\n", pulse)

internal/app/run.go

@@ -3,12 +3,12 @@ package app
 import (
 	"errors"
 	"fmt"
+	"git.ophivana.moe/cat/fortify/internal/final"
 	"os"
 	"os/exec"
 	"strings"
 
 	"git.ophivana.moe/cat/fortify/internal/state"
-	"git.ophivana.moe/cat/fortify/internal/system"
 	"git.ophivana.moe/cat/fortify/internal/util"
 	"git.ophivana.moe/cat/fortify/internal/verbose"
 )
@@ -47,31 +47,33 @@ func (a *App) Run() {
 	cmd.Stdin = os.Stdin
 	cmd.Stdout = os.Stdout
 	cmd.Stderr = os.Stderr
-	cmd.Dir = system.V.RunDir
+	cmd.Dir = a.runDirPath
 
 	verbose.Println("Executing:", cmd)
 
 	if err := cmd.Start(); err != nil {
-		state.Fatal("Error starting process:", err)
+		final.Fatal("Error starting process:", err)
 	}
 
-	state.RegisterEnablement(a.enablements)
+	final.RegisterEnablement(a.enablements)
 
-	if err := state.SaveProcess(a.Uid, cmd); err != nil {
+	if statePath, err := state.SaveProcess(a.Uid, cmd, a.runDirPath, a.command, a.enablements); err != nil {
 		// process already started, shouldn't be fatal
 		fmt.Println("Error registering process:", err)
+	} else {
+		final.RegisterStatePath(statePath)
 	}
 
 	var r int
 	if err := cmd.Wait(); err != nil {
 		var exitError *exec.ExitError
 		if !errors.As(err, &exitError) {
-			state.Fatal("Error running process:", err)
+			final.Fatal("Error running process:", err)
 		}
 	}
 
 	verbose.Println("Process exited with exit code", r)
-	state.BeforeExit()
+	final.BeforeExit()
 	os.Exit(r)
 }
 
@@ -99,7 +101,7 @@ func (a *App) commandBuilderSudo() (args []string) {
 
 func (a *App) commandBuilderBwrap() (args []string) {
 	// TODO: build bwrap command
-	state.Fatal("bwrap")
+	final.Fatal("bwrap")
 	panic("unreachable")
 }
 
@@ -127,7 +129,7 @@ func (a *App) commandBuilderMachineCtl() (args []string) {
 
 	// /bin/sh -c
 	if sh, ok := util.Which("sh"); !ok {
-		state.Fatal("Did not find 'sh' in PATH")
+		final.Fatal("Did not find 'sh' in PATH")
 	} else {
 		args = append(args, sh, "-c")
 	}
@@ -145,7 +147,7 @@ func (a *App) commandBuilderMachineCtl() (args []string) {
 	innerCommand.WriteString("; ")
 
 	if executable, err := os.Executable(); err != nil {
-		state.Fatal("Error reading executable path:", err)
+		final.Fatal("Error reading executable path:", err)
 	} else {
 		if a.enablements.Has(state.EnableDBus) {
 			innerCommand.WriteString(dbusSessionBusAddress + "=" + "'" + dbusAddress[0] + "' ")

internal/app/setup.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"os"
 	"os/user"
+	"path"
 	"strconv"
 
 	"git.ophivana.moe/cat/fortify/internal/state"
@@ -12,18 +13,25 @@ import (
 	"git.ophivana.moe/cat/fortify/internal/verbose"
 )
 
+const (
+	xdgRuntimeDir = "XDG_RUNTIME_DIR"
+)
+
 type App struct {
-	launchOptionText string
+	uid     int      // assigned
+	env     []string // modified via AppendEnv
+	command []string // set on initialisation
 
-	uid     int
-	env     []string
-	command []string
+	launchOptionText string // set on initialisation
+	launchOption     uint8  // assigned
 
-	launchOption uint8
-	toolPath     string
+	sharePath   string // set on initialisation
+	runtimePath string // assigned
+	runDirPath  string // assigned
+	toolPath    string // assigned
 
-	enablements state.Enablements
-	*user.User
+	enablements state.Enablements // set via setEnablement
+	*user.User                    // assigned
 
 	// absolutely *no* method of this type is thread-safe
 	// so don't treat it as if it is
@@ -33,6 +41,10 @@ func (a *App) LaunchOption() uint8 {
 	return a.launchOption
 }
 
+func (a *App) RunDir() string {
+	return a.runDirPath
+}
+
 func (a *App) setEnablement(e state.Enablement) {
 	if a.enablements.Has(e) {
 		panic("enablement " + e.String() + " set twice")
@@ -42,8 +54,25 @@ func (a *App) setEnablement(e state.Enablement) {
 }
 
 func New(userName string, args []string, launchOptionText string) *App {
-	a := &App{command: args, launchOptionText: launchOptionText}
+	a := &App{
+		command:          args,
+		launchOptionText: launchOptionText,
+		sharePath:        path.Join(os.TempDir(), "fortify."+strconv.Itoa(os.Geteuid())),
+	}
 
+	// runtimePath, runDirPath
+	if r, ok := os.LookupEnv(xdgRuntimeDir); !ok {
+		fmt.Println("Env variable", xdgRuntimeDir, "unset")
+
+		// too early for fatal
+		os.Exit(1)
+	} else {
+		a.runtimePath = r
+		a.runDirPath = path.Join(a.runtimePath, "fortify")
+		verbose.Println("Runtime directory at", a.runDirPath)
+	}
+
+	// *user.User
 	if u, err := user.Lookup(userName); err != nil {
 		if errors.As(err, new(user.UnknownUserError)) {
 			fmt.Println("unknown user", userName)
@@ -58,6 +87,7 @@ func New(userName string, args []string, launchOptionText string) *App {
 		a.User = u
 	}
 
+	// uid
 	if u, err := strconv.Atoi(a.Uid); err != nil {
 		// usually unreachable
 		panic("uid parse")
@@ -70,6 +100,7 @@ func New(userName string, args []string, launchOptionText string) *App {
 		verbose.Println("System booted with systemd as init system (PID 1).")
 	}
 
+	// launchOption, toolPath
 	switch a.launchOptionText {
 	case "sudo":
 		a.launchOption = LaunchMethodSudo

internal/app/wayland.go

@@ -2,12 +2,12 @@ package app
 
 import (
 	"fmt"
+	"git.ophivana.moe/cat/fortify/internal/final"
 	"os"
 	"path"
 
 	"git.ophivana.moe/cat/fortify/internal/acl"
 	"git.ophivana.moe/cat/fortify/internal/state"
-	"git.ophivana.moe/cat/fortify/internal/system"
 	"git.ophivana.moe/cat/fortify/internal/verbose"
 )
 
@@ -21,15 +21,15 @@ func (a *App) ShareWayland() {
 
 	// ensure Wayland socket ACL (e.g. `/run/user/%d/wayland-%d`)
 	if w, ok := os.LookupEnv(waylandDisplay); !ok {
-		state.Fatal("Wayland: WAYLAND_DISPLAY not set")
+		final.Fatal("Wayland: WAYLAND_DISPLAY not set")
 	} else {
 		// add environment variable for new process
-		wp := path.Join(system.V.Runtime, w)
+		wp := path.Join(a.runtimePath, w)
 		a.AppendEnv(waylandDisplay, wp)
 		if err := acl.UpdatePerm(wp, a.UID(), acl.Read, acl.Write, acl.Execute); err != nil {
-			state.Fatal(fmt.Sprintf("Error preparing Wayland '%s':", w), err)
+			final.Fatal(fmt.Sprintf("Error preparing Wayland '%s':", w), err)
 		} else {
-			state.RegisterRevertPath(wp)
+			final.RegisterRevertPath(wp)
 		}
 		verbose.Printf("Wayland socket '%s' configured\n", w)
 	}

internal/app/x.go

@@ -2,6 +2,7 @@ package app
 
 import (
 	"fmt"
+	"git.ophivana.moe/cat/fortify/internal/final"
 	"os"
 
 	"git.ophivana.moe/cat/fortify/internal/state"
@@ -16,16 +17,16 @@ func (a *App) ShareX() {
 
 	// discovery X11 and grant user permission via the `ChangeHosts` command
 	if d, ok := os.LookupEnv(display); !ok {
-		state.Fatal("X11: DISPLAY not set")
+		final.Fatal("X11: DISPLAY not set")
 	} else {
 		// add environment variable for new process
 		a.AppendEnv(display, d)
 
 		verbose.Printf("X11: Adding XHost entry SI:localuser:%s to display '%s'\n", a.Username, d)
 		if err := xcb.ChangeHosts(xcb.HostModeInsert, xcb.FamilyServerInterpreted, "localuser\x00"+a.Username); err != nil {
-			state.Fatal(fmt.Sprintf("Error adding XHost entry to '%s':", d), err)
+			final.Fatal(fmt.Sprintf("Error adding XHost entry to '%s':", d), err)
 		} else {
-			state.XcbActionComplete()
+			final.XcbActionComplete()
 		}
 	}
 }