release: 0.2.5

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

.gitea/workflows/nix.yml

@@ -22,5 +22,25 @@ jobs:
             system-features = nixos-test benchmark big-parallel kvm
           enable_kvm: true
 
+      - name: Ensure environment
+        run: >-
+          apt-get update && apt-get install -y sqlite3
+        if: ${{ runner.os == 'Linux' }}
+
+      - name: Restore Nix store
+        uses: nix-community/cache-nix-action@v5
+        with:
+          primary-key: nix-${{ runner.os }}-${{ hashFiles('**/*.nix') }}
+          restore-prefixes-first-match: nix-${{ runner.os }}-
+
       - name: Run tests
-        run: nix --print-build-logs --experimental-features 'nix-command flakes' flake check --all-systems
+        run: |
+          nix --print-build-logs --experimental-features 'nix-command flakes' flake check --all-systems
+          nix build --out-link "result" --print-out-paths --print-build-logs .#checks.x86_64-linux.nixos-tests
+
+      - name: Upload test output
+        uses: actions/upload-artifact@v3
+        with:
+          name: "result"
+          path: result/*
+          retention-days: 1

.gitea/workflows/test.yml

@@ -11,19 +11,22 @@ jobs:
     container:
       image: node:16-bookworm-slim
     steps:
-      - name: Get dependencies
+      - name: Enable backports
         run: >-
-          echo 'deb http://deb.debian.org/debian bookworm-backports main' >> /etc/apt/sources.list.d/backports.list &&
-          apt-get update &&
-          apt-get install -y
-          acl
-          git
-          gcc
-          pkg-config
-          libwayland-dev
-          wayland-protocols/bookworm-backports
-          libxcb1-dev
-          libacl1-dev
+          echo 'deb http://deb.debian.org/debian bookworm-backports main' >> /etc/apt/sources.list.d/backports.list
+        if: ${{ runner.os == 'Linux' }}
+
+      - name: Ensure environment
+        run: >-
+          apt-get update && apt-get install -y curl wget sudo libxml2
+        if: ${{ runner.os == 'Linux' }}
+
+      - name: Get dependencies
+        uses: awalsh128/cache-apt-pkgs-action@latest
+        with:
+          packages: acl git gcc pkg-config libwayland-dev wayland-protocols/bookworm-backports libxcb1-dev libacl1-dev
+          version: 1.0
+          #execute_install_scripts: true
         if: ${{ runner.os == 'Linux' }}
 
       - name: Checkout
@@ -44,13 +47,16 @@ jobs:
         run: >-
           go test ./...
 
-      - name: Build for Linux
+      - name: Build for test
+        id: build-test
         run: >-
-          go build -v -ldflags '-s -w
-          -X git.ophivana.moe/security/fortify/internal.Version=${{ github.ref_name }}
-          -X git.ophivana.moe/security/fortify/internal.Fsu=/usr/bin/fsu
-          -X git.ophivana.moe/security/fortify/internal.Finit=/usr/libexec/fortify/finit
-          -X main.Fmain=/usr/bin/fortify
-          -X main.Fshim=/usr/libexec/fortify/fshim'
-          -o bin/ ./... &&
-          (cd bin && sha512sum --tag -b * > sha512sums)
+          FORTIFY_VERSION="$(git rev-parse --short HEAD)"
+          bash -c './dist/release.sh &&
+          echo "rev=$FORTIFY_VERSION" >> $GITHUB_OUTPUT'
+
+      - name: Upload test build
+        uses: actions/upload-artifact@v3
+        with:
+          name: "fortify-${{ steps.build-test.outputs.rev }}"
+          path: dist/fortify-*
+          retention-days: 1

README.md

@@ -1,8 +1,8 @@
 Fortify
 =======
 
-[![Go Reference](https://pkg.go.dev/badge/git.ophivana.moe/security/fortify.svg)](https://pkg.go.dev/git.ophivana.moe/security/fortify)
-[![Go Report Card](https://goreportcard.com/badge/git.ophivana.moe/security/fortify)](https://goreportcard.com/report/git.ophivana.moe/security/fortify)
+[![Go Reference](https://pkg.go.dev/badge/git.gensokyo.uk/security/fortify.svg)](https://pkg.go.dev/git.gensokyo.uk/security/fortify)
+[![Go Report Card](https://goreportcard.com/badge/git.gensokyo.uk/security/fortify)](https://goreportcard.com/report/git.gensokyo.uk/security/fortify)
 
 Lets you run graphical applications as another user in a confined environment with a nice NixOS
 module to configure target users and provide launchers and desktop files for your privileged user.
@@ -18,7 +18,7 @@ Why would you want this?
 If you have a flakes-enabled nix environment, you can try out the tool by running:
 
 ```shell
-nix run git+https://git.ophivana.moe/security/fortify -- help
+nix run git+https://git.gensokyo.uk/security/fortify -- help
 ```
 
 ## Module usage
@@ -35,7 +35,7 @@ To use the module, import it into your configuration with
     nixpkgs.url = "github:NixOS/nixpkgs/nixos-24.05";
 
     fortify = {
-      url = "git+https://git.ophivana.moe/security/fortify";
+      url = "git+https://git.gensokyo.uk/security/fortify";
 
       # Optional but recommended to limit the size of your system closure.
       inputs.nixpkgs.follows = "nixpkgs";

acl/acl_test.go

@@ -7,7 +7,7 @@ import (
 	"reflect"
 	"testing"
 
-	"git.ophivana.moe/security/fortify/acl"
+	"git.gensokyo.uk/security/fortify/acl"
 )
 
 const testFileName = "acl.test"
@@ -15,8 +15,6 @@ const testFileName = "acl.test"
 var (
 	uid  = os.Geteuid()
 	cred = int32(os.Geteuid())
-
-	testFilePath = path.Join(os.TempDir(), testFileName)
 )
 
 func TestUpdatePerm(t *testing.T) {
@@ -25,6 +23,8 @@ func TestUpdatePerm(t *testing.T) {
 		t.SkipNow()
 	}
 
+	testFilePath := path.Join(t.TempDir(), testFileName)
+
 	if f, err := os.Create(testFilePath); err != nil {
 		t.Fatalf("Create: error = %v", err)
 	} else {
@@ -64,16 +64,16 @@ func TestUpdatePerm(t *testing.T) {
 		}
 	})
 
-	testUpdate(t, "r--", cur, fAclPermRead, acl.Read)
-	testUpdate(t, "-w-", cur, fAclPermWrite, acl.Write)
-	testUpdate(t, "--x", cur, fAclPermExecute, acl.Execute)
-	testUpdate(t, "-wx", cur, fAclPermWrite|fAclPermExecute, acl.Write, acl.Execute)
-	testUpdate(t, "r-x", cur, fAclPermRead|fAclPermExecute, acl.Read, acl.Execute)
-	testUpdate(t, "rw-", cur, fAclPermRead|fAclPermWrite, acl.Read, acl.Write)
-	testUpdate(t, "rwx", cur, fAclPermRead|fAclPermWrite|fAclPermExecute, acl.Read, acl.Write, acl.Execute)
+	testUpdate(t, testFilePath, "r--", cur, fAclPermRead, acl.Read)
+	testUpdate(t, testFilePath, "-w-", cur, fAclPermWrite, acl.Write)
+	testUpdate(t, testFilePath, "--x", cur, fAclPermExecute, acl.Execute)
+	testUpdate(t, testFilePath, "-wx", cur, fAclPermWrite|fAclPermExecute, acl.Write, acl.Execute)
+	testUpdate(t, testFilePath, "r-x", cur, fAclPermRead|fAclPermExecute, acl.Read, acl.Execute)
+	testUpdate(t, testFilePath, "rw-", cur, fAclPermRead|fAclPermWrite, acl.Read, acl.Write)
+	testUpdate(t, testFilePath, "rwx", cur, fAclPermRead|fAclPermWrite|fAclPermExecute, acl.Read, acl.Write, acl.Execute)
 }
 
-func testUpdate(t *testing.T, name string, cur []*getFAclResp, val fAclPerm, perms ...acl.Perm) {
+func testUpdate(t *testing.T, testFilePath, name string, cur []*getFAclResp, val fAclPerm, perms ...acl.Perm) {
 	t.Run(name, func(t *testing.T) {
 		t.Cleanup(func() {
 			if err := acl.UpdatePerm(testFilePath, uid); err != nil {

cmd/finit/main.go

@@ -1,19 +1,18 @@
 package main
 
 import (
-	"encoding/gob"
 	"errors"
 	"os"
 	"os/exec"
 	"os/signal"
 	"path"
-	"strconv"
 	"syscall"
 	"time"
 
-	init0 "git.ophivana.moe/security/fortify/cmd/finit/ipc"
-	"git.ophivana.moe/security/fortify/internal"
-	"git.ophivana.moe/security/fortify/internal/fmsg"
+	init0 "git.gensokyo.uk/security/fortify/cmd/finit/ipc"
+	"git.gensokyo.uk/security/fortify/internal"
+	"git.gensokyo.uk/security/fortify/internal/fmsg"
+	"git.gensokyo.uk/security/fortify/internal/proc"
 )
 
 const (
@@ -48,30 +47,24 @@ func main() {
 		}
 	}
 
-	// setup pipe fd from environment
-	var setup *os.File
-	if s, ok := os.LookupEnv(init0.Env); !ok {
-		fmsg.Fatal("FORTIFY_INIT not set")
-		panic("unreachable")
-	} else {
-		if fd, err := strconv.Atoi(s); err != nil {
-			fmsg.Fatalf("cannot parse %q: %v", s, err)
-			panic("unreachable")
-		} else {
-			setup = os.NewFile(uintptr(fd), "setup")
-			if setup == nil {
-				fmsg.Fatal("invalid config descriptor")
-				panic("unreachable")
-			}
+	// receive setup payload
+	var (
+		payload    init0.Payload
+		closeSetup func() error
+	)
+	if f, err := proc.Receive(init0.Env, &payload); err != nil {
+		if errors.Is(err, proc.ErrInvalid) {
+			fmsg.Fatal("invalid config descriptor")
+		}
+		if errors.Is(err, proc.ErrNotSet) {
+			fmsg.Fatal("FORTIFY_INIT not set")
 		}
-	}
 
-	var payload init0.Payload
-	if err := gob.NewDecoder(setup).Decode(&payload); err != nil {
-		fmsg.Fatal("cannot decode init setup payload:", err)
+		fmsg.Fatalf("cannot decode init setup payload: %v", err)
 		panic("unreachable")
 	} else {
 		fmsg.SetVerbose(payload.Verbose)
+		closeSetup = f
 
 		// child does not need to see this
 		if err = os.Unsetenv(init0.Env); err != nil {
@@ -98,7 +91,7 @@ func main() {
 	fmsg.Suspend()
 
 	// close setup pipe as setup is now complete
-	if err := setup.Close(); err != nil {
+	if err := closeSetup(); err != nil {
 		fmsg.Println("cannot close setup pipe:", err)
 		// not fatal
 	}

cmd/fshim/ipc/payload.go

@@ -1,11 +1,7 @@
 package shim0
 
 import (
-	"encoding/gob"
-	"net"
-
-	"git.ophivana.moe/security/fortify/helper/bwrap"
-	"git.ophivana.moe/security/fortify/internal/fmsg"
+	"git.gensokyo.uk/security/fortify/helper/bwrap"
 )
 
 const Env = "FORTIFY_SHIM"
@@ -23,13 +19,3 @@ type Payload struct {
 	// verbosity pass through
 	Verbose bool
 }
-
-func (p *Payload) Serve(conn *net.UnixConn) error {
-	if err := gob.NewEncoder(conn).Encode(*p); err != nil {
-		return fmsg.WrapErrorSuffix(err,
-			"cannot stream shim payload:")
-	}
-
-	return fmsg.WrapErrorSuffix(conn.Close(),
-		"cannot close setup connection:")
-}

cmd/fshim/ipc/shim/shim.go

@@ -1,22 +1,20 @@
 package shim
 
 import (
+	"encoding/gob"
 	"errors"
-	"net"
 	"os"
 	"os/exec"
 	"os/signal"
+	"strconv"
 	"strings"
-	"sync"
-	"sync/atomic"
 	"syscall"
 	"time"
 
-	"git.ophivana.moe/security/fortify/acl"
-	shim0 "git.ophivana.moe/security/fortify/cmd/fshim/ipc"
-	"git.ophivana.moe/security/fortify/internal"
-	"git.ophivana.moe/security/fortify/internal/fmsg"
-	"git.ophivana.moe/security/fortify/internal/proc"
+	shim0 "git.gensokyo.uk/security/fortify/cmd/fshim/ipc"
+	"git.gensokyo.uk/security/fortify/internal"
+	"git.gensokyo.uk/security/fortify/internal/fmsg"
+	"git.gensokyo.uk/security/fortify/internal/proc"
 )
 
 const shimSetupTimeout = 5 * time.Second
@@ -32,20 +30,14 @@ type Shim struct {
 	aid string
 	// string representation of supplementary group ids
 	supp []string
-	// path to setup socket
-	socket string
-	// shim setup abort reason and completion
-	abort     chan error
-	abortErr  atomic.Pointer[error]
-	abortOnce sync.Once
 	// fallback exit notifier with error returned killing the process
 	killFallback chan error
 	// shim setup payload
 	payload *shim0.Payload
 }
 
-func New(uid uint32, aid string, supp []string, socket string, payload *shim0.Payload) *Shim {
-	return &Shim{uid: uid, aid: aid, supp: supp, socket: socket, payload: payload}
+func New(uid uint32, aid string, supp []string, payload *shim0.Payload) *Shim {
+	return &Shim{uid: uid, aid: aid, supp: supp, payload: payload}
 }
 
 func (s *Shim) String() string {
@@ -59,39 +51,11 @@ func (s *Shim) Unwrap() *exec.Cmd {
 	return s.cmd
 }
 
-func (s *Shim) Abort(err error) {
-	s.abortOnce.Do(func() {
-		s.abortErr.Store(&err)
-		// s.abort is buffered so this will never block
-		s.abort <- err
-	})
-}
-
-func (s *Shim) AbortWait(err error) {
-	s.Abort(err)
-	<-s.abort
-}
-
 func (s *Shim) WaitFallback() chan error {
 	return s.killFallback
 }
 
 func (s *Shim) Start() (*time.Time, error) {
-	var (
-		cf     chan *net.UnixConn
-		accept func()
-	)
-
-	// listen on setup socket
-	if c, a, err := s.serve(); err != nil {
-		return nil, fmsg.WrapErrorSuffix(err,
-			"cannot listen on shim setup socket:")
-	} else {
-		// accepts a connection after each call to accept
-		// connections are sent to the channel cf
-		cf, accept = c, a
-	}
-
 	// start user switcher process and save time
 	var fsu string
 	if p, ok := internal.Check(internal.Fsu); !ok {
@@ -101,10 +65,19 @@ func (s *Shim) Start() (*time.Time, error) {
 		fsu = p
 	}
 	s.cmd = exec.Command(fsu)
-	s.cmd.Env = []string{
-		shim0.Env + "=" + s.socket,
-		"FORTIFY_APP_ID=" + s.aid,
+
+	var encoder *gob.Encoder
+	if fd, e, err := proc.Setup(&s.cmd.ExtraFiles); err != nil {
+		return nil, fmsg.WrapErrorSuffix(err,
+			"cannot create shim setup pipe:")
+	} else {
+		encoder = e
+		s.cmd.Env = []string{
+			shim0.Env + "=" + strconv.Itoa(fd),
+			"FORTIFY_APP_ID=" + s.aid,
+		}
 	}
+
 	if len(s.supp) > 0 {
 		fmsg.VPrintf("attaching supplementary group ids %s", s.supp)
 		s.cmd.Env = append(s.cmd.Env, "FORTIFY_GROUPS="+strings.Join(s.supp, " "))
@@ -145,117 +118,20 @@ func (s *Shim) Start() (*time.Time, error) {
 		signal.Ignore(syscall.SIGINT, syscall.SIGTERM)
 	}()
 
-	accept()
-	var conn *net.UnixConn
+	shimErr := make(chan error)
+	go func() { shimErr <- encoder.Encode(s.payload) }()
+
 	select {
-	case c := <-cf:
-		if c == nil {
-			return &startTime, fmsg.WrapErrorSuffix(*s.abortErr.Load(), "cannot accept call on setup socket:")
-		} else {
-			conn = c
+	case err := <-shimErr:
+		if err != nil {
+			return &startTime, fmsg.WrapErrorSuffix(err,
+				"cannot transmit shim config:")
 		}
-	case <-time.After(shimSetupTimeout):
-		err := fmsg.WrapError(errors.New("timed out waiting for shim"),
-			"timed out waiting for shim to connect")
-		s.AbortWait(err)
-		return &startTime, err
-	}
-
-	// authenticate against called provided uid and shim pid
-	if cred, err := peerCred(conn); err != nil {
-		return &startTime, fmsg.WrapErrorSuffix(*s.abortErr.Load(), "cannot retrieve shim credentials:")
-	} else if cred.Uid != s.uid {
-		fmsg.Printf("process %d owned by user %d tried to connect, expecting %d",
-			cred.Pid, cred.Uid, s.uid)
-		err = errors.New("compromised fortify build")
-		s.Abort(err)
-		return &startTime, err
-	} else if cred.Pid != int32(s.cmd.Process.Pid) {
-		fmsg.Printf("process %d tried to connect to shim setup socket, expecting shim %d",
-			cred.Pid, s.cmd.Process.Pid)
-		err = errors.New("compromised target user")
-		s.Abort(err)
-		return &startTime, err
-	}
-
-	// serve payload
-	// this also closes the connection
-	err := s.payload.Serve(conn)
-	if err == nil {
 		killShim = func() {}
+	case <-time.After(shimSetupTimeout):
+		return &startTime, fmsg.WrapError(errors.New("timed out waiting for shim"),
+			"timed out waiting for shim")
 	}
-	s.Abort(err) // aborting with nil indicates success
-	return &startTime, err
-}
-
-func (s *Shim) serve() (chan *net.UnixConn, func(), error) {
-	if s.abort != nil {
-		panic("attempted to serve shim setup twice")
-	}
-	s.abort = make(chan error, 1)
-
-	cf := make(chan *net.UnixConn)
-	accept := make(chan struct{}, 1)
-
-	if l, err := net.ListenUnix("unix", &net.UnixAddr{Name: s.socket, Net: "unix"}); err != nil {
-		return nil, nil, err
-	} else {
-		l.SetUnlinkOnClose(true)
-
-		fmsg.VPrintf("listening on shim setup socket %q", s.socket)
-		if err = acl.UpdatePerm(s.socket, int(s.uid), acl.Read, acl.Write, acl.Execute); err != nil {
-			fmsg.Println("cannot append ACL entry to shim setup socket:", err)
-			s.Abort(err) // ensures setup socket cleanup
-		}
-
-		go func() {
-			cfWg := new(sync.WaitGroup)
-			for {
-				select {
-				case err = <-s.abort:
-					if err != nil {
-						fmsg.VPrintln("aborting shim setup, reason:", err)
-					}
-					if err = l.Close(); err != nil {
-						fmsg.Println("cannot close setup socket:", err)
-					}
-					close(s.abort)
-					go func() {
-						cfWg.Wait()
-						close(cf)
-					}()
-					return
-				case <-accept:
-					cfWg.Add(1)
-					go func() {
-						defer cfWg.Done()
-						if conn, err0 := l.AcceptUnix(); err0 != nil {
-							// breaks loop
-							s.Abort(err0)
-							// receiver sees nil value and loads err0 stored during abort
-							cf <- nil
-						} else {
-							cf <- conn
-						}
-					}()
-				}
-			}
-		}()
-	}
-
-	return cf, func() { accept <- struct{}{} }, nil
-}
-
-// peerCred fetches peer credentials of conn
-func peerCred(conn *net.UnixConn) (ucred *syscall.Ucred, err error) {
-	var raw syscall.RawConn
-	if raw, err = conn.SyscallConn(); err != nil {
-		return
-	}
-
-	err0 := raw.Control(func(fd uintptr) {
-		ucred, err = syscall.GetsockoptUcred(int(fd), syscall.SOL_SOCKET, syscall.SO_PEERCRED)
-	})
-	err = errors.Join(err, err0)
-	return
+
+	return &startTime, nil
 }

cmd/fshim/main.go

@@ -1,18 +1,18 @@
 package main
 
 import (
-	"encoding/gob"
-	"net"
+	"errors"
 	"os"
 	"path"
 	"strconv"
 	"syscall"
 
-	init0 "git.ophivana.moe/security/fortify/cmd/finit/ipc"
-	shim "git.ophivana.moe/security/fortify/cmd/fshim/ipc"
-	"git.ophivana.moe/security/fortify/helper"
-	"git.ophivana.moe/security/fortify/internal"
-	"git.ophivana.moe/security/fortify/internal/fmsg"
+	init0 "git.gensokyo.uk/security/fortify/cmd/finit/ipc"
+	shim "git.gensokyo.uk/security/fortify/cmd/fshim/ipc"
+	"git.gensokyo.uk/security/fortify/helper"
+	"git.gensokyo.uk/security/fortify/internal"
+	"git.gensokyo.uk/security/fortify/internal/fmsg"
+	"git.gensokyo.uk/security/fortify/internal/proc"
 )
 
 // everything beyond this point runs as unconstrained target user
@@ -37,15 +37,6 @@ func main() {
 		}
 	}
 
-	// lookup socket path from environment
-	var socketPath string
-	if s, ok := os.LookupEnv(shim.Env); !ok {
-		fmsg.Fatal("FORTIFY_SHIM not set")
-		panic("unreachable")
-	} else {
-		socketPath = s
-	}
-
 	// check path to finit
 	var finitPath string
 	if p, ok := internal.Path(internal.Finit); !ok {
@@ -54,21 +45,24 @@ func main() {
 		finitPath = p
 	}
 
-	// dial setup socket
-	var conn *net.UnixConn
-	if c, err := net.DialUnix("unix", nil, &net.UnixAddr{Name: socketPath, Net: "unix"}); err != nil {
-		fmsg.Fatal(err.Error())
+	// receive setup payload
+	var (
+		payload    shim.Payload
+		closeSetup func() error
+	)
+	if f, err := proc.Receive(shim.Env, &payload); err != nil {
+		if errors.Is(err, proc.ErrInvalid) {
+			fmsg.Fatal("invalid config descriptor")
+		}
+		if errors.Is(err, proc.ErrNotSet) {
+			fmsg.Fatal("FORTIFY_SHIM not set")
+		}
+
+		fmsg.Fatalf("cannot decode shim setup payload: %v", err)
 		panic("unreachable")
-	} else {
-		conn = c
-	}
-
-	// decode payload gob stream
-	var payload shim.Payload
-	if err := gob.NewDecoder(conn).Decode(&payload); err != nil {
-		fmsg.Fatalf("cannot decode shim payload: %v", err)
 	} else {
 		fmsg.SetVerbose(payload.Verbose)
+		closeSetup = f
 	}
 
 	if payload.Bwrap == nil {
@@ -81,8 +75,8 @@ func main() {
 	}
 
 	// close setup socket
-	if err := conn.Close(); err != nil {
-		fmsg.Println("cannot close setup socket:", err)
+	if err := closeSetup(); err != nil {
+		fmsg.Println("cannot close setup pipe:", err)
 		// not fatal
 	}
 
@@ -110,17 +104,14 @@ func main() {
 
 	var extraFiles []*os.File
 
-	// share config pipe
-	if r, w, err := os.Pipe(); err != nil {
+	// serve setup payload
+	if fd, encoder, err := proc.Setup(&extraFiles); err != nil {
 		fmsg.Fatalf("cannot pipe: %v", err)
 	} else {
-		conf.SetEnv[init0.Env] = strconv.Itoa(3 + len(extraFiles))
-		extraFiles = append(extraFiles, r)
-
-		fmsg.VPrintln("transmitting config to init")
+		conf.SetEnv[init0.Env] = strconv.Itoa(fd)
 		go func() {
-			// stream config to pipe
-			if err = gob.NewEncoder(w).Encode(&ic); err != nil {
+			fmsg.VPrintln("transmitting config to init")
+			if err = encoder.Encode(&ic); err != nil {
 				fmsg.Fatalf("cannot transmit init config: %v", err)
 			}
 		}()

cmd/fsu/main.go

@@ -83,17 +83,17 @@ func main() {
 		uid += aid
 	}
 
-	// pass through setup path to shim
-	var shimSetupPath string
+	// pass through setup fd to shim
+	var shimSetupFd string
 	if s, ok := os.LookupEnv(envShim); !ok {
 		// fortify requests target uid
 		// print resolved uid and exit
 		fmt.Print(uid)
 		os.Exit(0)
-	} else if !path.IsAbs(s) {
-		log.Fatal("FORTIFY_SHIM is not absolute")
+	} else if len(s) != 1 || s[0] > '9' || s[0] < '3' {
+		log.Fatal("FORTIFY_SHIM holds an invalid value")
 	} else {
-		shimSetupPath = s
+		shimSetupFd = s
 	}
 
 	// supplementary groups
@@ -142,7 +142,7 @@ func main() {
 	if _, _, errno := syscall.AllThreadsSyscall(syscall.SYS_PRCTL, PR_SET_NO_NEW_PRIVS, 1, 0); errno != 0 {
 		log.Fatalf("cannot set no_new_privs flag: %s", errno.Error())
 	}
-	if err := syscall.Exec(fshim, []string{"fshim"}, []string{envShim + "=" + shimSetupPath}); err != nil {
+	if err := syscall.Exec(fshim, []string{"fshim"}, []string{envShim + "=" + shimSetupFd}); err != nil {
 		log.Fatalf("cannot start shim: %v", err)
 	}
 

cmd/fuserdb/main.go

@@ -9,7 +9,7 @@ import (
 	"path"
 	"strconv"
 
-	"git.ophivana.moe/security/fortify/internal/fmsg"
+	"git.gensokyo.uk/security/fortify/internal/fmsg"
 )
 
 func main() {

cmd/fuserdb/payload.go

@@ -5,7 +5,7 @@ import (
 	"os"
 	"path"
 
-	"git.ophivana.moe/security/fortify/internal/fmsg"
+	"git.gensokyo.uk/security/fortify/internal/fmsg"
 )
 
 type payloadU struct {

dbus/config_test.go

@@ -9,7 +9,7 @@ import (
 	"strings"
 	"testing"
 
-	"git.ophivana.moe/security/fortify/dbus"
+	"git.gensokyo.uk/security/fortify/dbus"
 )
 
 func TestConfig_Args(t *testing.T) {

dbus/dbus_test.go

@@ -5,8 +5,8 @@ import (
 	"strings"
 	"testing"
 
-	"git.ophivana.moe/security/fortify/dbus"
-	"git.ophivana.moe/security/fortify/helper"
+	"git.gensokyo.uk/security/fortify/dbus"
+	"git.gensokyo.uk/security/fortify/helper"
 )
 
 func TestNew(t *testing.T) {

dbus/proxy.go

@@ -6,8 +6,8 @@ import (
 	"io"
 	"sync"
 
-	"git.ophivana.moe/security/fortify/helper"
-	"git.ophivana.moe/security/fortify/helper/bwrap"
+	"git.gensokyo.uk/security/fortify/helper"
+	"git.gensokyo.uk/security/fortify/helper/bwrap"
 )
 
 // ProxyName is the file name or path to the proxy program.

dbus/run.go

@@ -9,9 +9,9 @@ import (
 	"strconv"
 	"strings"
 
-	"git.ophivana.moe/security/fortify/helper"
-	"git.ophivana.moe/security/fortify/helper/bwrap"
-	"git.ophivana.moe/security/fortify/ldd"
+	"git.gensokyo.uk/security/fortify/helper"
+	"git.gensokyo.uk/security/fortify/helper/bwrap"
+	"git.gensokyo.uk/security/fortify/ldd"
 )
 
 // Start launches the D-Bus proxy and sets up the Wait method.

dbus/samples_test.go

@@ -3,7 +3,7 @@ package dbus_test
 import (
 	"sync"
 
-	"git.ophivana.moe/security/fortify/dbus"
+	"git.gensokyo.uk/security/fortify/dbus"
 )
 
 var samples = []dbusTestCase{

dbus/stub_test.go

@@ -3,7 +3,7 @@ package dbus_test
 import (
 	"testing"
 
-	"git.ophivana.moe/security/fortify/helper"
+	"git.gensokyo.uk/security/fortify/helper"
 )
 
 func TestHelperChildStub(t *testing.T) {

dist/release.sh

@@ -8,9 +8,9 @@ mkdir -p "${out}"
 cp "README.md" "dist/fsurc.default" "dist/install.sh" "${out}"
 
 go build -v -o "${out}/bin/" -ldflags "-s -w
-  -X git.ophivana.moe/security/fortify/internal.Version=${VERSION}
-  -X git.ophivana.moe/security/fortify/internal.Fsu=/usr/bin/fsu
-  -X git.ophivana.moe/security/fortify/internal.Finit=/usr/libexec/fortify/finit
+  -X git.gensokyo.uk/security/fortify/internal.Version=${VERSION}
+  -X git.gensokyo.uk/security/fortify/internal.Fsu=/usr/bin/fsu
+  -X git.gensokyo.uk/security/fortify/internal.Finit=/usr/libexec/fortify/finit
   -X main.Fmain=/usr/bin/fortify
   -X main.Fshim=/usr/libexec/fortify/fshim" ./...
 

error.go

@@ -3,8 +3,8 @@ package main
 import (
 	"errors"
 
-	"git.ophivana.moe/security/fortify/internal/app"
-	"git.ophivana.moe/security/fortify/internal/fmsg"
+	"git.gensokyo.uk/security/fortify/internal/app"
+	"git.gensokyo.uk/security/fortify/internal/fmsg"
 )
 
 func logWaitError(err error) {

flake.nix

@@ -74,7 +74,7 @@
                 touch $out
               '';
 
-          nixos-tests = callPackage ./test.nix { inherit self home-manager; };
+          nixos-tests = callPackage ./test.nix { inherit system self home-manager; };
         }
       );
 
@@ -95,6 +95,26 @@
           buildInputs = with nixpkgsFor.${system}; self.packages.${system}.fortify.buildInputs;
         };
 
+        fhs = nixpkgsFor.${system}.buildFHSEnv {
+          pname = "fortify-fhs";
+          inherit (self.packages.${system}.fortify) version;
+          targetPkgs =
+            pkgs: with pkgs; [
+              go
+              gcc
+              pkg-config
+              acl
+              wayland
+              wayland-scanner
+              wayland-protocols
+              xorg.libxcb
+            ];
+          extraOutputsToInstall = [ "dev" ];
+          profile = ''
+            export PKG_CONFIG_PATH="/usr/share/pkgconfig:$PKG_CONFIG_PATH"
+          '';
+        };
+
         withPackage = nixpkgsFor.${system}.mkShell {
           buildInputs =
             with nixpkgsFor.${system};

fst/config.go

@@ -1,12 +1,12 @@
-package app
+package fst
 
 import (
 	"errors"
 
-	"git.ophivana.moe/security/fortify/dbus"
-	"git.ophivana.moe/security/fortify/helper/bwrap"
-	"git.ophivana.moe/security/fortify/internal/linux"
-	"git.ophivana.moe/security/fortify/internal/system"
+	"git.gensokyo.uk/security/fortify/dbus"
+	"git.gensokyo.uk/security/fortify/helper/bwrap"
+	"git.gensokyo.uk/security/fortify/internal/linux"
+	"git.gensokyo.uk/security/fortify/internal/system"
 )
 
 const fTmp = "/fortify"

fst/id.go

@@ -0,0 +1,48 @@
+package fst
+
+import (
+	"crypto/rand"
+	"encoding/hex"
+	"errors"
+	"fmt"
+)
+
+type ID [16]byte
+
+var (
+	ErrInvalidLength = errors.New("string representation must have a length of 32")
+)
+
+func (a *ID) String() string {
+	return hex.EncodeToString(a[:])
+}
+
+func NewAppID(id *ID) error {
+	_, err := rand.Read(id[:])
+	return err
+}
+
+func ParseAppID(id *ID, s string) error {
+	if len(s) != 32 {
+		return ErrInvalidLength
+	}
+
+	for i, b := range s {
+		if b < '0' || b > 'f' {
+			return fmt.Errorf("invalid char %q at byte %d", b, i)
+		}
+
+		v := uint8(b)
+		if v > '9' {
+			v = 10 + v - 'a'
+		} else {
+			v -= '0'
+		}
+		if i%2 == 0 {
+			v <<= 4
+		}
+		id[i/2] += v
+	}
+
+	return nil
+}

fst/id_test.go

@@ -0,0 +1,63 @@
+package fst_test
+
+import (
+	"errors"
+	"testing"
+
+	"git.gensokyo.uk/security/fortify/fst"
+)
+
+func TestParseAppID(t *testing.T) {
+	t.Run("bad length", func(t *testing.T) {
+		if err := fst.ParseAppID(new(fst.ID), "meow"); !errors.Is(err, fst.ErrInvalidLength) {
+			t.Errorf("ParseAppID: error = %v, wantErr =  %v", err, fst.ErrInvalidLength)
+		}
+	})
+
+	t.Run("bad byte", func(t *testing.T) {
+		wantErr := "invalid char '\\n' at byte 15"
+		if err := fst.ParseAppID(new(fst.ID), "02bc7f8936b2af6\n\ne2535cd71ef0bb7"); err == nil || err.Error() != wantErr {
+			t.Errorf("ParseAppID: error = %v, wantErr =  %v", err, wantErr)
+		}
+	})
+
+	t.Run("fuzz 16 iterations", func(t *testing.T) {
+		for i := 0; i < 16; i++ {
+			testParseAppIDWithRandom(t)
+		}
+	})
+}
+
+func FuzzParseAppID(f *testing.F) {
+	for i := 0; i < 16; i++ {
+		id := new(fst.ID)
+		if err := fst.NewAppID(id); err != nil {
+			panic(err.Error())
+		}
+		f.Add(id[0], id[1], id[2], id[3], id[4], id[5], id[6], id[7], id[8], id[9], id[10], id[11], id[12], id[13], id[14], id[15])
+	}
+
+	f.Fuzz(func(t *testing.T, b0, b1, b2, b3, b4, b5, b6, b7, b8, b9, b10, b11, b12, b13, b14, b15 byte) {
+		testParseAppID(t, &fst.ID{b0, b1, b2, b3, b4, b5, b6, b7, b8, b9, b10, b11, b12, b13, b14, b15})
+	})
+}
+
+func testParseAppIDWithRandom(t *testing.T) {
+	id := new(fst.ID)
+	if err := fst.NewAppID(id); err != nil {
+		t.Fatalf("cannot generate app ID: %v", err)
+	}
+	testParseAppID(t, id)
+}
+
+func testParseAppID(t *testing.T, id *fst.ID) {
+	s := id.String()
+	got := new(fst.ID)
+	if err := fst.ParseAppID(got, s); err != nil {
+		t.Fatalf("cannot parse app ID: %v", err)
+	}
+
+	if *got != *id {
+		t.Fatalf("ParseAppID(%#v) = \n%#v, want \n%#v", s, got, id)
+	}
+}

fst/shared.go

@@ -0,0 +1,2 @@
+// Package fst exports shared fortify types.
+package fst

go.mod

@@ -1,3 +1,3 @@
-module git.ophivana.moe/security/fortify
+module git.gensokyo.uk/security/fortify
 
 go 1.22

helper/args_test.go

@@ -6,7 +6,7 @@ import (
 	"strings"
 	"testing"
 
-	"git.ophivana.moe/security/fortify/helper"
+	"git.gensokyo.uk/security/fortify/helper"
 )
 
 func Test_argsFD_String(t *testing.T) {

helper/bwrap.go

@@ -8,8 +8,8 @@ import (
 	"strconv"
 	"sync"
 
-	"git.ophivana.moe/security/fortify/helper/bwrap"
-	"git.ophivana.moe/security/fortify/internal/proc"
+	"git.gensokyo.uk/security/fortify/helper/bwrap"
+	"git.gensokyo.uk/security/fortify/internal/proc"
 )
 
 // BubblewrapName is the file name or path to bubblewrap.

helper/bwrap_test.go

@@ -7,8 +7,8 @@ import (
 	"strings"
 	"testing"
 
-	"git.ophivana.moe/security/fortify/helper"
-	"git.ophivana.moe/security/fortify/helper/bwrap"
+	"git.gensokyo.uk/security/fortify/helper"
+	"git.gensokyo.uk/security/fortify/helper/bwrap"
 )
 
 func TestBwrap(t *testing.T) {

helper/direct_test.go

@@ -5,7 +5,7 @@ import (
 	"os"
 	"testing"
 
-	"git.ophivana.moe/security/fortify/helper"
+	"git.gensokyo.uk/security/fortify/helper"
 )
 
 func TestDirect(t *testing.T) {

helper/helper_test.go

@@ -6,7 +6,7 @@ import (
 	"testing"
 	"time"
 
-	"git.ophivana.moe/security/fortify/helper"
+	"git.gensokyo.uk/security/fortify/helper"
 )
 
 var (

helper/pipe.go

@@ -6,7 +6,7 @@ import (
 	"os"
 	"os/exec"
 
-	"git.ophivana.moe/security/fortify/internal/proc"
+	"git.gensokyo.uk/security/fortify/internal/proc"
 )
 
 type pipes struct {

helper/stub.go

@@ -10,8 +10,8 @@ import (
 	"syscall"
 	"testing"
 
-	"git.ophivana.moe/security/fortify/helper/bwrap"
-	"git.ophivana.moe/security/fortify/internal/fmsg"
+	"git.gensokyo.uk/security/fortify/helper/bwrap"
+	"git.gensokyo.uk/security/fortify/internal/fmsg"
 )
 
 // InternalChildStub is an internal function but exported because it is cross-package;

helper/stub_test.go

@@ -3,7 +3,7 @@ package helper_test
 import (
 	"testing"
 
-	"git.ophivana.moe/security/fortify/helper"
+	"git.gensokyo.uk/security/fortify/helper"
 )
 
 func TestHelperChildStub(t *testing.T) {

internal/app/app.go

@@ -2,14 +2,16 @@ package app
 
 import (
 	"sync"
+	"sync/atomic"
 
-	"git.ophivana.moe/security/fortify/cmd/fshim/ipc/shim"
-	"git.ophivana.moe/security/fortify/internal/linux"
+	"git.gensokyo.uk/security/fortify/cmd/fshim/ipc/shim"
+	"git.gensokyo.uk/security/fortify/fst"
+	"git.gensokyo.uk/security/fortify/internal/linux"
 )
 
 type App interface {
 	// ID returns a copy of App's unique ID.
-	ID() ID
+	ID() fst.ID
 	// Start sets up the system and starts the App.
 	Start() error
 	// Wait waits for App's process to exit and reverts system setup.
@@ -17,13 +19,16 @@ type App interface {
 	// WaitErr returns error returned by the underlying wait syscall.
 	WaitErr() error
 
-	Seal(config *Config) error
+	Seal(config *fst.Config) error
 	String() string
 }
 
 type app struct {
+	// single-use config reference
+	ct *appCt
+
 	// application unique identifier
-	id *ID
+	id *fst.ID
 	// operating system interface
 	os linux.System
 	// shim process manager
@@ -36,7 +41,7 @@ type app struct {
 	lock sync.RWMutex
 }
 
-func (a *app) ID() ID {
+func (a *app) ID() fst.ID {
 	return *a.id
 }
 
@@ -65,7 +70,28 @@ func (a *app) WaitErr() error {
 
 func New(os linux.System) (App, error) {
 	a := new(app)
-	a.id = new(ID)
+	a.id = new(fst.ID)
 	a.os = os
-	return a, newAppID(a.id)
+	return a, fst.NewAppID(a.id)
+}
+
+// appCt ensures its wrapped val is only accessed once
+type appCt struct {
+	val  *fst.Config
+	done *atomic.Bool
+}
+
+func (a *appCt) Unwrap() *fst.Config {
+	if !a.done.Load() {
+		defer a.done.Store(true)
+		return a.val
+	}
+	panic("attempted to access config reference twice")
+}
+
+func newAppCt(config *fst.Config) (ct *appCt) {
+	ct = new(appCt)
+	ct.done = new(atomic.Bool)
+	ct.val = config
+	return ct
 }

internal/app/app_nixos_test.go

@@ -1,25 +1,25 @@
 package app_test
 
 import (
-	"git.ophivana.moe/security/fortify/acl"
-	"git.ophivana.moe/security/fortify/dbus"
-	"git.ophivana.moe/security/fortify/helper/bwrap"
-	"git.ophivana.moe/security/fortify/internal/app"
-	"git.ophivana.moe/security/fortify/internal/system"
+	"git.gensokyo.uk/security/fortify/acl"
+	"git.gensokyo.uk/security/fortify/dbus"
+	"git.gensokyo.uk/security/fortify/fst"
+	"git.gensokyo.uk/security/fortify/helper/bwrap"
+	"git.gensokyo.uk/security/fortify/internal/system"
 )
 
 var testCasesNixos = []sealTestCase{
 	{
 		"nixos chromium direct wayland", new(stubNixOS),
-		&app.Config{
+		&fst.Config{
 			ID:      "org.chromium.Chromium",
 			Command: []string{"/nix/store/yqivzpzzn7z5x0lq9hmbzygh45d8rhqd-chromium-start"},
-			Confinement: app.ConfinementConfig{
+			Confinement: fst.ConfinementConfig{
 				AppID: 1, Groups: []string{}, Username: "u0_a1",
 				Outer: "/var/lib/persist/module/fortify/0/1",
-				Sandbox: &app.SandboxConfig{
+				Sandbox: &fst.SandboxConfig{
 					UserNS: true, Net: true, MapRealUID: true, DirectWayland: true, Env: nil,
-					Filesystem: []*app.FilesystemConfig{
+					Filesystem: []*fst.FilesystemConfig{
 						{Src: "/bin", Must: true}, {Src: "/usr/bin", Must: true},
 						{Src: "/nix/store", Must: true}, {Src: "/run/current-system", Must: true},
 						{Src: "/sys/block"}, {Src: "/sys/bus"}, {Src: "/sys/class"}, {Src: "/sys/dev"}, {Src: "/sys/devices"},
@@ -48,7 +48,7 @@ var testCasesNixos = []sealTestCase{
 				Enablements: system.EWayland.Mask() | system.EDBus.Mask() | system.EPulse.Mask(),
 			},
 		},
-		app.ID{
+		fst.ID{
 			0x8e, 0x2c, 0x76, 0xb0,
 			0x66, 0xda, 0xbe, 0x57,
 			0x4c, 0xf0, 0x73, 0xbd,

internal/app/app_pd_test.go

@@ -1,25 +1,25 @@
 package app_test
 
 import (
-	"git.ophivana.moe/security/fortify/acl"
-	"git.ophivana.moe/security/fortify/dbus"
-	"git.ophivana.moe/security/fortify/helper/bwrap"
-	"git.ophivana.moe/security/fortify/internal/app"
-	"git.ophivana.moe/security/fortify/internal/system"
+	"git.gensokyo.uk/security/fortify/acl"
+	"git.gensokyo.uk/security/fortify/dbus"
+	"git.gensokyo.uk/security/fortify/fst"
+	"git.gensokyo.uk/security/fortify/helper/bwrap"
+	"git.gensokyo.uk/security/fortify/internal/system"
 )
 
 var testCasesPd = []sealTestCase{
 	{
 		"nixos permissive defaults no enablements", new(stubNixOS),
-		&app.Config{
+		&fst.Config{
 			Command: make([]string, 0),
-			Confinement: app.ConfinementConfig{
+			Confinement: fst.ConfinementConfig{
 				AppID:    0,
 				Username: "chronos",
 				Outer:    "/home/chronos",
 			},
 		},
-		app.ID{
+		fst.ID{
 			0x4a, 0x45, 0x0b, 0x65,
 			0x96, 0xd7, 0xbc, 0x15,
 			0xbd, 0x01, 0x78, 0x0e,
@@ -190,10 +190,10 @@ var testCasesPd = []sealTestCase{
 	},
 	{
 		"nixos permissive defaults chromium", new(stubNixOS),
-		&app.Config{
+		&fst.Config{
 			ID:      "org.chromium.Chromium",
 			Command: []string{"/run/current-system/sw/bin/zsh", "-c", "exec chromium "},
-			Confinement: app.ConfinementConfig{
+			Confinement: fst.ConfinementConfig{
 				AppID:    9,
 				Groups:   []string{"video"},
 				Username: "chronos",
@@ -232,7 +232,7 @@ var testCasesPd = []sealTestCase{
 				Enablements: system.EWayland.Mask() | system.EDBus.Mask() | system.EPulse.Mask(),
 			},
 		},
-		app.ID{
+		fst.ID{
 			0xeb, 0xf0, 0x83, 0xd1,
 			0xb1, 0x75, 0x91, 0x17,
 			0x82, 0xd4, 0x13, 0x36,

internal/app/app_stub_test.go

@@ -7,7 +7,7 @@ import (
 	"os/user"
 	"strconv"
 
-	"git.ophivana.moe/security/fortify/internal/linux"
+	"git.gensokyo.uk/security/fortify/internal/linux"
 )
 
 // fs methods are not implemented using a real FS

internal/app/app_test.go

@@ -6,17 +6,18 @@ import (
 	"testing"
 	"time"
 
-	"git.ophivana.moe/security/fortify/helper/bwrap"
-	"git.ophivana.moe/security/fortify/internal/app"
-	"git.ophivana.moe/security/fortify/internal/linux"
-	"git.ophivana.moe/security/fortify/internal/system"
+	"git.gensokyo.uk/security/fortify/fst"
+	"git.gensokyo.uk/security/fortify/helper/bwrap"
+	"git.gensokyo.uk/security/fortify/internal/app"
+	"git.gensokyo.uk/security/fortify/internal/linux"
+	"git.gensokyo.uk/security/fortify/internal/system"
 )
 
 type sealTestCase struct {
 	name      string
 	os        linux.System
-	config    *app.Config
-	id        app.ID
+	config    *fst.Config
+	id        fst.ID
 	wantSys   *system.I
 	wantBwrap *bwrap.Config
 }

internal/app/export_test.go

@@ -1,12 +1,13 @@
 package app
 
 import (
-	"git.ophivana.moe/security/fortify/helper/bwrap"
-	"git.ophivana.moe/security/fortify/internal/linux"
-	"git.ophivana.moe/security/fortify/internal/system"
+	"git.gensokyo.uk/security/fortify/fst"
+	"git.gensokyo.uk/security/fortify/helper/bwrap"
+	"git.gensokyo.uk/security/fortify/internal/linux"
+	"git.gensokyo.uk/security/fortify/internal/system"
 )
 
-func NewWithID(id ID, os linux.System) App {
+func NewWithID(id fst.ID, os linux.System) App {
 	a := new(app)
 	a.id = &id
 	a.os = os

internal/app/id.go

@@ -1,17 +0,0 @@
-package app
-
-import (
-	"crypto/rand"
-	"encoding/hex"
-)
-
-type ID [16]byte
-
-func (a *ID) String() string {
-	return hex.EncodeToString(a[:])
-}
-
-func newAppID(id *ID) error {
-	_, err := rand.Read(id[:])
-	return err
-}

internal/app/seal.go

@@ -8,11 +8,12 @@ import (
 	"regexp"
 	"strconv"
 
-	"git.ophivana.moe/security/fortify/dbus"
-	"git.ophivana.moe/security/fortify/internal/fmsg"
-	"git.ophivana.moe/security/fortify/internal/linux"
-	"git.ophivana.moe/security/fortify/internal/state"
-	"git.ophivana.moe/security/fortify/internal/system"
+	"git.gensokyo.uk/security/fortify/dbus"
+	"git.gensokyo.uk/security/fortify/fst"
+	"git.gensokyo.uk/security/fortify/internal/fmsg"
+	"git.gensokyo.uk/security/fortify/internal/linux"
+	"git.gensokyo.uk/security/fortify/internal/state"
+	"git.gensokyo.uk/security/fortify/internal/system"
 )
 
 var (
@@ -59,7 +60,7 @@ type appSeal struct {
 }
 
 // Seal seals the app launch context
-func (a *app) Seal(config *Config) error {
+func (a *app) Seal(config *fst.Config) error {
 	a.lock.Lock()
 	defer a.lock.Unlock()
 
@@ -147,7 +148,7 @@ func (a *app) Seal(config *Config) error {
 		fmsg.VPrintln("sandbox configuration not supplied, PROCEED WITH CAUTION")
 
 		// permissive defaults
-		conf := &SandboxConfig{
+		conf := &fst.SandboxConfig{
 			UserNS:       true,
 			Net:          true,
 			NoNewSession: true,
@@ -157,7 +158,7 @@ func (a *app) Seal(config *Config) error {
 		if d, err := a.os.ReadDir("/"); err != nil {
 			return err
 		} else {
-			b := make([]*FilesystemConfig, 0, len(d))
+			b := make([]*fst.FilesystemConfig, 0, len(d))
 			for _, ent := range d {
 				p := "/" + ent.Name()
 				switch p {
@@ -169,7 +170,7 @@ func (a *app) Seal(config *Config) error {
 				case "/etc":
 
 				default:
-					b = append(b, &FilesystemConfig{Src: p, Write: true, Must: true})
+					b = append(b, &fst.FilesystemConfig{Src: p, Write: true, Must: true})
 				}
 			}
 			conf.Filesystem = append(conf.Filesystem, b...)
@@ -178,7 +179,7 @@ func (a *app) Seal(config *Config) error {
 		if d, err := a.os.ReadDir("/run"); err != nil {
 			return err
 		} else {
-			b := make([]*FilesystemConfig, 0, len(d))
+			b := make([]*fst.FilesystemConfig, 0, len(d))
 			for _, ent := range d {
 				name := ent.Name()
 				switch name {
@@ -186,7 +187,7 @@ func (a *app) Seal(config *Config) error {
 				case "dbus":
 				default:
 					p := "/run/" + name
-					b = append(b, &FilesystemConfig{Src: p, Write: true, Must: true})
+					b = append(b, &fst.FilesystemConfig{Src: p, Write: true, Must: true})
 				}
 			}
 			conf.Filesystem = append(conf.Filesystem, b...)
@@ -198,7 +199,7 @@ func (a *app) Seal(config *Config) error {
 		}
 		// bind GPU stuff
 		if config.Confinement.Enablements.Has(system.EX11) || config.Confinement.Enablements.Has(system.EWayland) {
-			conf.Filesystem = append(conf.Filesystem, &FilesystemConfig{Src: "/dev/dri", Device: true})
+			conf.Filesystem = append(conf.Filesystem, &fst.FilesystemConfig{Src: "/dev/dri", Device: true})
 		}
 
 		config.Confinement.Sandbox = conf
@@ -217,7 +218,7 @@ func (a *app) Seal(config *Config) error {
 	// open process state store
 	// the simple store only starts holding an open file after first action
 	// store activity begins after Start is called and must end before Wait
-	seal.store = state.NewSimple(seal.RunDirPath, seal.sys.user.as)
+	seal.store = state.NewMulti(seal.RunDirPath)
 
 	// initialise system interface with full uid
 	seal.sys.I = system.New(seal.sys.user.uid)
@@ -236,5 +237,6 @@ func (a *app) Seal(config *Config) error {
 
 	// seal app and release lock
 	a.seal = seal
+	a.ct = newAppCt(config)
 	return nil
 }

internal/app/share.dbus.go

@@ -3,9 +3,9 @@ package app
 import (
 	"path"
 
-	"git.ophivana.moe/security/fortify/acl"
-	"git.ophivana.moe/security/fortify/dbus"
-	"git.ophivana.moe/security/fortify/internal/system"
+	"git.gensokyo.uk/security/fortify/acl"
+	"git.gensokyo.uk/security/fortify/dbus"
+	"git.gensokyo.uk/security/fortify/internal/system"
 )
 
 const (

internal/app/share.display.go

@@ -4,10 +4,10 @@ import (
 	"errors"
 	"path"
 
-	"git.ophivana.moe/security/fortify/acl"
-	"git.ophivana.moe/security/fortify/internal/fmsg"
-	"git.ophivana.moe/security/fortify/internal/linux"
-	"git.ophivana.moe/security/fortify/internal/system"
+	"git.gensokyo.uk/security/fortify/acl"
+	"git.gensokyo.uk/security/fortify/internal/fmsg"
+	"git.gensokyo.uk/security/fortify/internal/linux"
+	"git.gensokyo.uk/security/fortify/internal/system"
 )
 
 const (

internal/app/share.pulse.go

@@ -6,9 +6,9 @@ import (
 	"io/fs"
 	"path"
 
-	"git.ophivana.moe/security/fortify/internal/fmsg"
-	"git.ophivana.moe/security/fortify/internal/linux"
-	"git.ophivana.moe/security/fortify/internal/system"
+	"git.gensokyo.uk/security/fortify/internal/fmsg"
+	"git.gensokyo.uk/security/fortify/internal/linux"
+	"git.gensokyo.uk/security/fortify/internal/system"
 )
 
 const (

internal/app/share.runtime.go

@@ -3,8 +3,8 @@ package app
 import (
 	"path"
 
-	"git.ophivana.moe/security/fortify/acl"
-	"git.ophivana.moe/security/fortify/internal/system"
+	"git.gensokyo.uk/security/fortify/acl"
+	"git.gensokyo.uk/security/fortify/internal/system"
 )
 
 const (

internal/app/share.system.go

@@ -3,9 +3,9 @@ package app
 import (
 	"path"
 
-	"git.ophivana.moe/security/fortify/acl"
-	"git.ophivana.moe/security/fortify/internal/linux"
-	"git.ophivana.moe/security/fortify/internal/system"
+	"git.gensokyo.uk/security/fortify/acl"
+	"git.gensokyo.uk/security/fortify/internal/linux"
+	"git.gensokyo.uk/security/fortify/internal/system"
 )
 
 const (

internal/app/start.go

@@ -4,16 +4,15 @@ import (
 	"errors"
 	"fmt"
 	"os/exec"
-	"path"
 	"path/filepath"
 	"strings"
 
-	shim0 "git.ophivana.moe/security/fortify/cmd/fshim/ipc"
-	"git.ophivana.moe/security/fortify/cmd/fshim/ipc/shim"
-	"git.ophivana.moe/security/fortify/helper"
-	"git.ophivana.moe/security/fortify/internal/fmsg"
-	"git.ophivana.moe/security/fortify/internal/state"
-	"git.ophivana.moe/security/fortify/internal/system"
+	shim0 "git.gensokyo.uk/security/fortify/cmd/fshim/ipc"
+	"git.gensokyo.uk/security/fortify/cmd/fshim/ipc/shim"
+	"git.gensokyo.uk/security/fortify/helper"
+	"git.gensokyo.uk/security/fortify/internal/fmsg"
+	"git.gensokyo.uk/security/fortify/internal/state"
+	"git.gensokyo.uk/security/fortify/internal/system"
 )
 
 // Start selects a user switcher and starts shim.
@@ -46,7 +45,6 @@ func (a *app) Start() error {
 		uint32(a.seal.sys.UID()),
 		a.seal.sys.user.as,
 		a.seal.sys.user.supp,
-		path.Join(a.seal.share, "shim"),
 		&shim0.Payload{
 			Argv:  a.seal.command,
 			Exec:  shimExec,
@@ -70,17 +68,16 @@ func (a *app) Start() error {
 	} else {
 		// shim start and setup success, create process state
 		sd := state.State{
-			PID:        a.shim.Unwrap().Process.Pid,
-			Command:    a.seal.command,
-			Capability: a.seal.et,
-			Argv:       a.shim.Unwrap().Args,
-			Time:       *startTime,
+			ID:     *a.id,
+			PID:    a.shim.Unwrap().Process.Pid,
+			Config: a.ct.Unwrap(),
+			Time:   *startTime,
 		}
 
 		// register process state
 		var err0 = new(StateStoreError)
-		err0.Inner, err0.DoErr = a.seal.store.Do(func(b state.Backend) {
-			err0.InnerErr = b.Save(&sd)
+		err0.Inner, err0.DoErr = a.seal.store.Do(a.seal.sys.user.aid, func(c state.Cursor) {
+			err0.InnerErr = c.Save(&sd)
 		})
 		a.seal.sys.saveState = true
 		return err0.equiv("cannot save process state:")
@@ -202,11 +199,11 @@ func (a *app) Wait() (int, error) {
 
 	// update store and revert app setup transaction
 	e := new(StateStoreError)
-	e.Inner, e.DoErr = a.seal.store.Do(func(b state.Backend) {
+	e.Inner, e.DoErr = a.seal.store.Do(a.seal.sys.user.aid, func(b state.Cursor) {
 		e.InnerErr = func() error {
 			// destroy defunct state entry
 			if cmd := a.shim.Unwrap(); cmd != nil && a.seal.sys.saveState {
-				if err := b.Destroy(cmd.Process.Pid); err != nil {
+				if err := b.Destroy(*a.id); err != nil {
 					return err
 				}
 			}
@@ -227,8 +224,12 @@ func (a *app) Wait() (int, error) {
 				}
 
 				// accumulate capabilities of other launchers
-				for _, s := range states {
-					*rt |= s.Capability
+				for i, s := range states {
+					if s.Config != nil {
+						*rt |= s.Config.Confinement.Enablements
+					} else {
+						fmsg.Printf("state entry %d does not contain config", i)
+					}
 				}
 			}
 			// invert accumulated enablements for cleanup
@@ -249,12 +250,6 @@ func (a *app) Wait() (int, error) {
 				}
 			}
 
-			if a.shim.Unwrap() == nil {
-				fmsg.VPrintln("fault before shim start")
-			} else {
-				a.shim.AbortWait(errors.New("shim exited"))
-			}
-
 			if a.seal.sys.needRevert {
 				if err := a.seal.sys.Revert(ec); err != nil {
 					return err.(RevertCompoundError)

internal/app/system.go

@@ -1,10 +1,10 @@
 package app
 
 import (
-	"git.ophivana.moe/security/fortify/dbus"
-	"git.ophivana.moe/security/fortify/helper/bwrap"
-	"git.ophivana.moe/security/fortify/internal/linux"
-	"git.ophivana.moe/security/fortify/internal/system"
+	"git.gensokyo.uk/security/fortify/dbus"
+	"git.gensokyo.uk/security/fortify/helper/bwrap"
+	"git.gensokyo.uk/security/fortify/internal/linux"
+	"git.gensokyo.uk/security/fortify/internal/system"
 )
 
 // appSealSys encapsulates app seal behaviour with OS interactions

internal/linux/interface.go

@@ -7,7 +7,7 @@ import (
 	"path"
 	"strconv"
 
-	"git.ophivana.moe/security/fortify/internal/fmsg"
+	"git.gensokyo.uk/security/fortify/internal/fmsg"
 )
 
 // System provides safe access to operating system resources.
@@ -39,8 +39,6 @@ type System interface {
 	Paths() Paths
 	// Uid invokes fsu and returns target uid.
 	Uid(aid int) (int, error)
-	// SdBooted implements https://www.freedesktop.org/software/systemd/man/sd_booted.html
-	SdBooted() bool
 }
 
 // Paths contains environment dependent paths used by fortify.

internal/linux/std.go

@@ -1,7 +1,6 @@
 package linux
 
 import (
-	"errors"
 	"io"
 	"io/fs"
 	"os"
@@ -10,8 +9,8 @@ import (
 	"strconv"
 	"sync"
 
-	"git.ophivana.moe/security/fortify/internal"
-	"git.ophivana.moe/security/fortify/internal/fmsg"
+	"git.gensokyo.uk/security/fortify/internal"
+	"git.gensokyo.uk/security/fortify/internal/fmsg"
 )
 
 // Std implements System using the standard library.
@@ -19,9 +18,6 @@ type Std struct {
 	paths     Paths
 	pathsOnce sync.Once
 
-	sdBooted     bool
-	sdBootedOnce sync.Once
-
 	uidOnce sync.Once
 	uidCopy map[int]struct {
 		uid int
@@ -90,31 +86,3 @@ func (s *Std) Uid(aid int) (int, error) {
 		return u.uid, u.err
 	}
 }
-
-func (s *Std) SdBooted() bool {
-	s.sdBootedOnce.Do(func() { s.sdBooted = copySdBooted() })
-	return s.sdBooted
-}
-
-const systemdCheckPath = "/run/systemd/system"
-
-func copySdBooted() bool {
-	if v, err := sdBooted(); err != nil {
-		fmsg.Println("cannot read systemd marker:", err)
-		return false
-	} else {
-		return v
-	}
-}
-
-func sdBooted() (bool, error) {
-	_, err := os.Stat(systemdCheckPath)
-	if err != nil {
-		if errors.Is(err, fs.ErrNotExist) {
-			err = nil
-		}
-		return false, err
-	}
-
-	return true, nil
-}

internal/proc/fd.go

@@ -0,0 +1,42 @@
+package proc
+
+import (
+	"encoding/gob"
+	"errors"
+	"os"
+	"strconv"
+)
+
+var (
+	ErrNotSet  = errors.New("environment variable not set")
+	ErrInvalid = errors.New("bad file descriptor")
+)
+
+func Setup(extraFiles *[]*os.File) (int, *gob.Encoder, error) {
+	if r, w, err := os.Pipe(); err != nil {
+		return -1, nil, err
+	} else {
+		fd := 3 + len(*extraFiles)
+		*extraFiles = append(*extraFiles, r)
+		return fd, gob.NewEncoder(w), nil
+	}
+}
+
+func Receive(key string, e any) (func() error, error) {
+	var setup *os.File
+
+	if s, ok := os.LookupEnv(key); !ok {
+		return nil, ErrNotSet
+	} else {
+		if fd, err := strconv.Atoi(s); err != nil {
+			return nil, err
+		} else {
+			setup = os.NewFile(uintptr(fd), "setup")
+			if setup == nil {
+				return nil, ErrInvalid
+			}
+		}
+	}
+
+	return func() error { return setup.Close() }, gob.NewDecoder(setup).Decode(e)
+}

internal/state/multi.go

@@ -0,0 +1,292 @@
+package state
+
+import (
+	"encoding/gob"
+	"errors"
+	"fmt"
+	"io/fs"
+	"os"
+	"path"
+	"strconv"
+	"sync"
+	"syscall"
+
+	"git.gensokyo.uk/security/fortify/fst"
+	"git.gensokyo.uk/security/fortify/internal/fmsg"
+)
+
+// fine-grained locking and access
+type multiStore struct {
+	base string
+
+	// initialised backends
+	backends *sync.Map
+
+	lock sync.RWMutex
+}
+
+func (s *multiStore) Do(aid int, f func(c Cursor)) (bool, error) {
+	s.lock.RLock()
+	defer s.lock.RUnlock()
+
+	// load or initialise new backend
+	b := new(multiBackend)
+	if v, ok := s.backends.LoadOrStore(aid, b); ok {
+		b = v.(*multiBackend)
+	} else {
+		b.lock.Lock()
+		b.path = path.Join(s.base, strconv.Itoa(aid))
+
+		// ensure directory
+		if err := os.MkdirAll(b.path, 0700); err != nil && !errors.Is(err, fs.ErrExist) {
+			s.backends.CompareAndDelete(aid, b)
+			return false, err
+		}
+
+		// open locker file
+		if l, err := os.OpenFile(b.path+".lock", os.O_RDWR|os.O_CREATE, 0600); err != nil {
+			s.backends.CompareAndDelete(aid, b)
+			return false, err
+		} else {
+			b.lockfile = l
+		}
+		b.lock.Unlock()
+	}
+
+	// lock backend
+	if err := b.lockFile(); err != nil {
+		return false, err
+	}
+
+	// expose backend methods without exporting the pointer
+	c := new(struct{ *multiBackend })
+	c.multiBackend = b
+	f(b)
+	// disable access to the backend on a best-effort basis
+	c.multiBackend = nil
+
+	// unlock backend
+	return true, b.unlockFile()
+}
+
+func (s *multiStore) List() ([]int, error) {
+	var entries []os.DirEntry
+
+	// read base directory to get all aids
+	if v, err := os.ReadDir(s.base); err != nil && !errors.Is(err, os.ErrNotExist) {
+		return nil, err
+	} else {
+		entries = v
+	}
+
+	aidsBuf := make([]int, 0, len(entries))
+	for _, e := range entries {
+		// skip non-directories
+		if !e.IsDir() {
+			fmsg.VPrintf("skipped non-directory entry %q", e.Name())
+			continue
+		}
+
+		// skip non-numerical names
+		if v, err := strconv.Atoi(e.Name()); err != nil {
+			fmsg.VPrintf("skipped non-aid entry %q", e.Name())
+			continue
+		} else {
+			if v < 0 || v > 9999 {
+				fmsg.VPrintf("skipped out of bounds entry %q", e.Name())
+				continue
+			}
+
+			aidsBuf = append(aidsBuf, v)
+		}
+	}
+
+	return append([]int(nil), aidsBuf...), nil
+}
+
+func (s *multiStore) Close() error {
+	s.lock.Lock()
+	defer s.lock.Unlock()
+
+	var errs []error
+	s.backends.Range(func(_, value any) bool {
+		b := value.(*multiBackend)
+		errs = append(errs, b.close())
+		return true
+	})
+
+	return errors.Join(errs...)
+}
+
+type multiBackend struct {
+	path string
+
+	// created/opened by prepare
+	lockfile *os.File
+
+	lock sync.RWMutex
+}
+
+func (b *multiBackend) filename(id *fst.ID) string {
+	return path.Join(b.path, id.String())
+}
+
+func (b *multiBackend) lockFileAct(lt int) (err error) {
+	op := "LockAct"
+	switch lt {
+	case syscall.LOCK_EX:
+		op = "Lock"
+	case syscall.LOCK_UN:
+		op = "Unlock"
+	}
+
+	for {
+		err = syscall.Flock(int(b.lockfile.Fd()), lt)
+		if !errors.Is(err, syscall.EINTR) {
+			break
+		}
+	}
+	if err != nil {
+		return &fs.PathError{
+			Op:   op,
+			Path: b.lockfile.Name(),
+			Err:  err,
+		}
+	}
+	return nil
+}
+
+func (b *multiBackend) lockFile() error {
+	return b.lockFileAct(syscall.LOCK_EX)
+}
+
+func (b *multiBackend) unlockFile() error {
+	return b.lockFileAct(syscall.LOCK_UN)
+}
+
+// reads all launchers in simpleBackend
+// file contents are ignored if decode is false
+func (b *multiBackend) load(decode bool) (Entries, error) {
+	b.lock.RLock()
+	defer b.lock.RUnlock()
+
+	// read directory contents, should only contain files named after ids
+	var entries []os.DirEntry
+	if pl, err := os.ReadDir(b.path); err != nil {
+		return nil, err
+	} else {
+		entries = pl
+	}
+
+	// allocate as if every entry is valid
+	// since that should be the case assuming no external interference happens
+	r := make(Entries, len(entries))
+
+	for _, e := range entries {
+		if e.IsDir() {
+			return nil, fmt.Errorf("unexpected directory %q in store", e.Name())
+		}
+
+		id := new(fst.ID)
+		if err := fst.ParseAppID(id, e.Name()); err != nil {
+			return nil, err
+		}
+
+		// run in a function to better handle file closing
+		if err := func() error {
+			// open state file for reading
+			if f, err := os.Open(path.Join(b.path, e.Name())); err != nil {
+				return err
+			} else {
+				defer func() {
+					if f.Close() != nil {
+						// unreachable
+						panic("foreign state file closed prematurely")
+					}
+				}()
+
+				s := new(State)
+				r[*id] = s
+
+				// append regardless, but only parse if required, used to implement Len
+				if decode {
+					if err = gob.NewDecoder(f).Decode(s); err != nil {
+						return err
+					}
+
+					if s.ID != *id {
+						return fmt.Errorf("state entry %s has unexpected id %s", id, &s.ID)
+					}
+				}
+
+				return nil
+			}
+		}(); err != nil {
+			return nil, err
+		}
+	}
+
+	return r, nil
+}
+
+// Save writes process state to filesystem
+func (b *multiBackend) Save(state *State) error {
+	b.lock.Lock()
+	defer b.lock.Unlock()
+
+	if state.Config == nil {
+		return errors.New("state does not contain config")
+	}
+
+	statePath := b.filename(&state.ID)
+
+	// create and open state data file
+	if f, err := os.OpenFile(statePath, os.O_RDWR|os.O_CREATE|os.O_EXCL, 0600); err != nil {
+		return err
+	} else {
+		defer func() {
+			if f.Close() != nil {
+				// unreachable
+				panic("state file closed prematurely")
+			}
+		}()
+		// encode into state file
+		return gob.NewEncoder(f).Encode(state)
+	}
+}
+
+func (b *multiBackend) Destroy(id fst.ID) error {
+	b.lock.Lock()
+	defer b.lock.Unlock()
+
+	return os.Remove(b.filename(&id))
+}
+
+func (b *multiBackend) Load() (Entries, error) {
+	return b.load(true)
+}
+
+func (b *multiBackend) Len() (int, error) {
+	// rn consists of only nil entries but has the correct length
+	rn, err := b.load(false)
+	return len(rn), err
+}
+
+func (b *multiBackend) close() error {
+	b.lock.Lock()
+	defer b.lock.Unlock()
+
+	err := b.lockfile.Close()
+	if err == nil || errors.Is(err, os.ErrInvalid) || errors.Is(err, os.ErrClosed) {
+		return nil
+	}
+	return err
+}
+
+// NewMulti returns an instance of the multi-file store.
+func NewMulti(runDir string) Store {
+	b := new(multiStore)
+	b.base = path.Join(runDir, "state")
+	b.backends = new(sync.Map)
+	return b
+}

internal/state/multi_test.go

@@ -0,0 +1,11 @@
+package state_test
+
+import (
+	"testing"
+
+	"git.gensokyo.uk/security/fortify/internal/state"
+)
+
+func TestMulti(t *testing.T) {
+	testStore(t, state.NewMulti(t.TempDir()))
+}

internal/state/print.go

@@ -1,62 +1,45 @@
 package state
 
 import (
-	"errors"
 	"fmt"
 	"os"
-	"path"
-	"strconv"
 	"strings"
 	"text/tabwriter"
 	"time"
 
-	"git.ophivana.moe/security/fortify/internal/fmsg"
-	"git.ophivana.moe/security/fortify/internal/system"
+	"git.gensokyo.uk/security/fortify/internal/fmsg"
+	"git.gensokyo.uk/security/fortify/internal/system"
 )
 
 // MustPrintLauncherStateSimpleGlobal prints active launcher states of all simple stores
 // in an implementation-specific way.
 func MustPrintLauncherStateSimpleGlobal(w **tabwriter.Writer, runDir string) {
 	now := time.Now().UTC()
+	s := NewMulti(runDir)
 
 	// read runtime directory to get all UIDs
-	if dirs, err := os.ReadDir(path.Join(runDir, "state")); err != nil && !errors.Is(err, os.ErrNotExist) {
-		fmsg.Fatal("cannot read runtime directory:", err)
+	if aids, err := s.List(); err != nil {
+		fmsg.Fatal("cannot list store:", err)
 	} else {
-		for _, e := range dirs {
-			// skip non-directories
-			if !e.IsDir() {
-				fmsg.VPrintf("skipped non-directory entry %q", e.Name())
-				continue
-			}
-
-			// skip non-numerical names
-			if _, err = strconv.Atoi(e.Name()); err != nil {
-				fmsg.VPrintf("skipped non-uid entry %q", e.Name())
-				continue
-			}
-
-			// obtain temporary store
-			s := NewSimple(runDir, e.Name()).(*simpleStore)
-
+		for _, aid := range aids {
 			// print states belonging to this store
-			s.mustPrintLauncherState(w, now)
-
-			// mustPrintLauncherState causes store activity so store needs to be closed
-			if err = s.Close(); err != nil {
-				fmsg.Printf("cannot close store for user %q: %s", e.Name(), err)
-			}
+			s.(*multiStore).mustPrintLauncherState(aid, w, now)
 		}
 	}
+
+	// mustPrintLauncherState causes store activity so store needs to be closed
+	if err := s.Close(); err != nil {
+		fmsg.Printf("cannot close store: %v", err)
+	}
 }
 
-func (s *simpleStore) mustPrintLauncherState(w **tabwriter.Writer, now time.Time) {
+func (s *multiStore) mustPrintLauncherState(aid int, w **tabwriter.Writer, now time.Time) {
 	var innerErr error
 
-	if ok, err := s.Do(func(b Backend) {
+	if ok, err := s.Do(aid, func(c Cursor) {
 		innerErr = func() error {
 			// read launcher states
-			states, err := b.Load()
+			states, err := c.Load()
 			if err != nil {
 				return err
 			}
@@ -82,40 +65,54 @@ func (s *simpleStore) mustPrintLauncherState(w **tabwriter.Writer, now time.Time
 					continue
 				}
 
-				// build enablements string
-				ets := strings.Builder{}
-				// append enablement strings in order
-				for i := system.Enablement(0); i < system.Enablement(system.ELen); i++ {
-					if state.Capability.Has(i) {
-						ets.WriteString(", " + i.String())
+				// build enablements and command string
+				var (
+					ets *strings.Builder
+					cs  = "(No command information)"
+				)
+
+				// check if enablements are provided
+				if state.Config != nil {
+					ets = new(strings.Builder)
+					// append enablement strings in order
+					for i := system.Enablement(0); i < system.Enablement(system.ELen); i++ {
+						if state.Config.Confinement.Enablements.Has(i) {
+							ets.WriteString(", " + i.String())
+						}
 					}
+
+					cs = fmt.Sprintf("%q", state.Config.Command)
 				}
-				// prevent an empty string when
-				if ets.Len() == 0 {
-					ets.WriteString("(No enablements)")
+				if ets != nil {
+					// prevent an empty string
+					if ets.Len() == 0 {
+						ets.WriteString("(No enablements)")
+					}
+				} else {
+					ets = new(strings.Builder)
+					ets.WriteString("(No confinement information)")
 				}
 
 				if !fmsg.Verbose() {
-					_, _ = fmt.Fprintf(*w, "\t%d\t%s\t%s\t%s\t%s\n",
-						state.PID, s.path[len(s.path)-1], now.Sub(state.Time).Round(time.Second).String(), strings.TrimPrefix(ets.String(), ", "),
-						state.Command)
+					_, _ = fmt.Fprintf(*w, "\t%d\t%d\t%s\t%s\t%s\n",
+						state.PID, aid, now.Sub(state.Time).Round(time.Second).String(), strings.TrimPrefix(ets.String(), ", "), cs)
 				} else {
 					// emit argv instead when verbose
-					_, _ = fmt.Fprintf(*w, "\t%d\t%s\t%s\n",
-						state.PID, s.path[len(s.path)-1], state.Argv)
+					_, _ = fmt.Fprintf(*w, "\t%d\t%d\t%s\n",
+						state.PID, aid, state.ID)
 				}
 			}
 
 			return nil
 		}()
 	}); err != nil {
-		fmsg.Printf("cannot perform action on store %q: %s", path.Join(s.path...), err)
+		fmsg.Printf("cannot perform action on app %d: %v", aid, err)
 		if !ok {
 			fmsg.Fatal("store faulted before printing")
 		}
 	}
 
 	if innerErr != nil {
-		fmsg.Fatalf("cannot print launcher state for store %q: %s", path.Join(s.path...), innerErr)
+		fmsg.Fatalf("cannot print launcher state of app %d: %s", aid, innerErr)
 	}
 }

internal/state/simple.go

@@ -1,218 +0,0 @@
-package state
-
-import (
-	"encoding/gob"
-	"errors"
-	"io/fs"
-	"os"
-	"path"
-	"strconv"
-	"sync"
-	"syscall"
-)
-
-// file-based locking
-type simpleStore struct {
-	path []string
-
-	// created/opened by prepare
-	lockfile *os.File
-	// enforce prepare method
-	init sync.Once
-	// error returned by prepare
-	initErr error
-
-	lock sync.Mutex
-}
-
-func (s *simpleStore) Do(f func(b Backend)) (bool, error) {
-	s.init.Do(s.prepare)
-	if s.initErr != nil {
-		return false, s.initErr
-	}
-
-	s.lock.Lock()
-	defer s.lock.Unlock()
-
-	// lock store
-	if err := s.lockFile(); err != nil {
-		return false, err
-	}
-
-	// initialise new backend for caller
-	b := new(simpleBackend)
-	b.path = path.Join(s.path...)
-	f(b)
-	// disable backend
-	b.lock.Lock()
-
-	// unlock store
-	return true, s.unlockFile()
-}
-
-func (s *simpleStore) lockFileAct(lt int) (err error) {
-	op := "LockAct"
-	switch lt {
-	case syscall.LOCK_EX:
-		op = "Lock"
-	case syscall.LOCK_UN:
-		op = "Unlock"
-	}
-
-	for {
-		err = syscall.Flock(int(s.lockfile.Fd()), lt)
-		if !errors.Is(err, syscall.EINTR) {
-			break
-		}
-	}
-	if err != nil {
-		return &fs.PathError{
-			Op:   op,
-			Path: s.lockfile.Name(),
-			Err:  err,
-		}
-	}
-	return nil
-}
-
-func (s *simpleStore) lockFile() error {
-	return s.lockFileAct(syscall.LOCK_EX)
-}
-
-func (s *simpleStore) unlockFile() error {
-	return s.lockFileAct(syscall.LOCK_UN)
-}
-
-func (s *simpleStore) prepare() {
-	s.initErr = func() error {
-		prefix := path.Join(s.path...)
-		// ensure directory
-		if err := os.MkdirAll(prefix, 0700); err != nil && !errors.Is(err, fs.ErrExist) {
-			return err
-		}
-
-		// open locker file
-		if f, err := os.OpenFile(prefix+".lock", os.O_RDWR|os.O_CREATE, 0600); err != nil {
-			return err
-		} else {
-			s.lockfile = f
-		}
-
-		return nil
-	}()
-}
-
-func (s *simpleStore) Close() error {
-	s.lock.Lock()
-	defer s.lock.Unlock()
-
-	err := s.lockfile.Close()
-	if err == nil || errors.Is(err, os.ErrInvalid) || errors.Is(err, os.ErrClosed) {
-		return nil
-	}
-	return err
-}
-
-type simpleBackend struct {
-	path string
-
-	lock sync.RWMutex
-}
-
-func (b *simpleBackend) filename(pid int) string {
-	return path.Join(b.path, strconv.Itoa(pid))
-}
-
-// reads all launchers in simpleBackend
-// file contents are ignored if decode is false
-func (b *simpleBackend) load(decode bool) ([]*State, error) {
-	b.lock.RLock()
-	defer b.lock.RUnlock()
-
-	var (
-		r []*State
-		f *os.File
-	)
-
-	// read directory contents, should only contain files named after PIDs
-	if pl, err := os.ReadDir(b.path); err != nil {
-		return nil, err
-	} else {
-		for _, e := range pl {
-			// run in a function to better handle file closing
-			if err = func() error {
-				// open state file for reading
-				if f, err = os.Open(path.Join(b.path, e.Name())); err != nil {
-					return err
-				} else {
-					defer func() {
-						if f.Close() != nil {
-							// unreachable
-							panic("foreign state file closed prematurely")
-						}
-					}()
-
-					var s State
-					r = append(r, &s)
-
-					// append regardless, but only parse if required, used to implement Len
-					if decode {
-						return gob.NewDecoder(f).Decode(&s)
-					} else {
-						return nil
-					}
-				}
-			}(); err != nil {
-				return nil, err
-			}
-		}
-	}
-
-	return r, nil
-}
-
-// Save writes process state to filesystem
-func (b *simpleBackend) Save(state *State) error {
-	b.lock.Lock()
-	defer b.lock.Unlock()
-
-	statePath := b.filename(state.PID)
-
-	// create and open state data file
-	if f, err := os.OpenFile(statePath, os.O_RDWR|os.O_CREATE|os.O_EXCL, 0600); err != nil {
-		return err
-	} else {
-		defer func() {
-			if f.Close() != nil {
-				// unreachable
-				panic("state file closed prematurely")
-			}
-		}()
-		// encode into state file
-		return gob.NewEncoder(f).Encode(state)
-	}
-}
-
-func (b *simpleBackend) Destroy(pid int) error {
-	b.lock.Lock()
-	defer b.lock.Unlock()
-
-	return os.Remove(b.filename(pid))
-}
-
-func (b *simpleBackend) Load() ([]*State, error) {
-	return b.load(true)
-}
-
-func (b *simpleBackend) Len() (int, error) {
-	// rn consists of only nil entries but has the correct length
-	rn, err := b.load(false)
-	return len(rn), err
-}
-
-// NewSimple returns an instance of a file-based store.
-func NewSimple(runDir string, prefix ...string) Store {
-	b := new(simpleStore)
-	b.path = append([]string{runDir, "state"}, prefix...)
-	return b
-}

internal/state/state.go

@@ -3,38 +3,42 @@ package state
 import (
 	"time"
 
-	"git.ophivana.moe/security/fortify/internal/system"
+	"git.gensokyo.uk/security/fortify/fst"
 )
 
+type Entries map[fst.ID]*State
+
 type Store interface {
 	// Do calls f exactly once and ensures store exclusivity until f returns.
 	// Returns whether f is called and any errors during the locking process.
-	// Backend provided to f becomes invalid as soon as f returns.
-	Do(f func(b Backend)) (bool, error)
+	// Cursor provided to f becomes invalid as soon as f returns.
+	Do(aid int, f func(c Cursor)) (ok bool, err error)
+
+	// List queries the store and returns a list of aids known to the store.
+	// Note that some or all returned aids might not have any active apps.
+	List() (aids []int, err error)
 
 	// Close releases any resources held by Store.
 	Close() error
 }
 
-// Backend provides access to the store
-type Backend interface {
+// Cursor provides access to the store
+type Cursor interface {
 	Save(state *State) error
-	Destroy(pid int) error
-	Load() ([]*State, error)
+	Destroy(id fst.ID) error
+	Load() (Entries, error)
 	Len() (int, error)
 }
 
 // State is the on-disk format for a fortified process's state information
 type State struct {
+	// fortify instance id
+	ID fst.ID `json:"instance"`
 	// child process PID value
-	PID int
-	// command used to seal the app
-	Command []string
-	// capability enablements applied to child
-	Capability system.Enablements
+	PID int `json:"pid"`
+	// sealed app configuration
+	Config *fst.Config `json:"config"`
 
-	// full argv whe launching
-	Argv []string
 	// process start time
 	Time time.Time
 }

internal/state/state_test.go

@@ -0,0 +1,126 @@
+package state_test
+
+import (
+	"math/rand/v2"
+	"reflect"
+	"slices"
+	"testing"
+	"time"
+
+	"git.gensokyo.uk/security/fortify/fst"
+	"git.gensokyo.uk/security/fortify/internal/state"
+)
+
+func testStore(t *testing.T, s state.Store) {
+	t.Run("list empty store", func(t *testing.T) {
+		if aids, err := s.List(); err != nil {
+			t.Fatalf("List: error = %v", err)
+		} else if len(aids) != 0 {
+			t.Fatalf("List: aids = %#v", aids)
+		}
+	})
+
+	const (
+		insertEntryChecked = iota
+		insertEntryNoCheck
+		insertEntryOtherApp
+
+		tl
+	)
+
+	var tc [tl]state.State
+	for i := 0; i < tl; i++ {
+		makeState(t, &tc[i])
+	}
+
+	do := func(aid int, f func(c state.Cursor)) {
+		if ok, err := s.Do(aid, f); err != nil {
+			t.Fatalf("Do: ok = %v, error = %v", ok, err)
+		}
+	}
+
+	insert := func(i, aid int) {
+		do(aid, func(c state.Cursor) {
+			if err := c.Save(&tc[i]); err != nil {
+				t.Fatalf("Save(&tc[%v]): error = %v", i, err)
+			}
+		})
+	}
+
+	check := func(i, aid int) {
+		do(aid, func(c state.Cursor) {
+			if entries, err := c.Load(); err != nil {
+				t.Fatalf("Load: error = %v", err)
+			} else if got, ok := entries[tc[i].ID]; !ok {
+				t.Fatalf("Load: entry %s missing",
+					&tc[i].ID)
+			} else {
+				got.Time = tc[i].Time
+				if !reflect.DeepEqual(got, &tc[i]) {
+					t.Fatalf("Load: entry %s got %#v, want %#v",
+						&tc[i].ID, got, &tc[i])
+				}
+			}
+		})
+	}
+
+	t.Run("insert entry checked", func(t *testing.T) {
+		insert(insertEntryChecked, 0)
+		check(insertEntryChecked, 0)
+	})
+
+	t.Run("insert entry unchecked", func(t *testing.T) {
+		insert(insertEntryNoCheck, 0)
+	})
+
+	t.Run("insert entry different aid", func(t *testing.T) {
+		insert(insertEntryOtherApp, 1)
+		check(insertEntryOtherApp, 1)
+	})
+
+	t.Run("check previous insertion", func(t *testing.T) {
+		check(insertEntryNoCheck, 0)
+	})
+
+	t.Run("list aids", func(t *testing.T) {
+		if aids, err := s.List(); err != nil {
+			t.Fatalf("List: error = %v", err)
+		} else {
+			slices.Sort(aids)
+			want := []int{0, 1}
+			if slices.Compare(aids, want) != 0 {
+				t.Fatalf("List() = %#v, want %#v", aids, want)
+			}
+		}
+	})
+
+	t.Run("clear aid 1", func(t *testing.T) {
+		do(1, func(c state.Cursor) {
+			if err := c.Destroy(tc[insertEntryOtherApp].ID); err != nil {
+				t.Fatalf("Destroy: error = %v", err)
+			}
+		})
+		do(1, func(c state.Cursor) {
+			if l, err := c.Len(); err != nil {
+				t.Fatalf("Len: error = %v", err)
+			} else if l != 0 {
+				t.Fatalf("Len() = %d, want 0", l)
+			}
+		})
+	})
+
+	t.Run("close store", func(t *testing.T) {
+		if err := s.Close(); err != nil {
+			t.Fatalf("Close: error = %v", err)
+		}
+	})
+}
+
+func makeState(t *testing.T, s *state.State) {
+	if err := fst.NewAppID(&s.ID); err != nil {
+		t.Fatalf("cannot create dummy state: %v", err)
+	}
+	s.Config = fst.Template()
+	s.PID = rand.Int()
+	s.Time = time.Now()
+}

internal/system/acl.go

@@ -4,8 +4,8 @@ import (
 	"fmt"
 	"slices"
 
-	"git.ophivana.moe/security/fortify/acl"
-	"git.ophivana.moe/security/fortify/internal/fmsg"
+	"git.gensokyo.uk/security/fortify/acl"
+	"git.gensokyo.uk/security/fortify/internal/fmsg"
 )
 
 // UpdatePerm appends an ephemeral acl update Op.

internal/system/acl_test.go

@@ -3,7 +3,7 @@ package system
 import (
 	"testing"
 
-	"git.ophivana.moe/security/fortify/acl"
+	"git.gensokyo.uk/security/fortify/acl"
 )
 
 func TestUpdatePerm(t *testing.T) {

internal/system/dbus.go

@@ -7,8 +7,8 @@ import (
 	"strings"
 	"sync"
 
-	"git.ophivana.moe/security/fortify/dbus"
-	"git.ophivana.moe/security/fortify/internal/fmsg"
+	"git.gensokyo.uk/security/fortify/dbus"
+	"git.gensokyo.uk/security/fortify/internal/fmsg"
 )
 
 var (

internal/system/mkdir.go

@@ -5,7 +5,7 @@ import (
 	"fmt"
 	"os"
 
-	"git.ophivana.moe/security/fortify/internal/fmsg"
+	"git.gensokyo.uk/security/fortify/internal/fmsg"
 )
 
 // Ensure the existence and mode of a directory.

internal/system/op.go

@@ -5,7 +5,7 @@ import (
 	"os"
 	"sync"
 
-	"git.ophivana.moe/security/fortify/internal/fmsg"
+	"git.gensokyo.uk/security/fortify/internal/fmsg"
 )
 
 const (

internal/system/op_test.go

@@ -4,7 +4,7 @@ import (
 	"strconv"
 	"testing"
 
-	"git.ophivana.moe/security/fortify/internal/system"
+	"git.gensokyo.uk/security/fortify/internal/system"
 )
 
 func TestNew(t *testing.T) {

internal/system/tmpfiles.go

@@ -7,8 +7,8 @@ import (
 	"os"
 	"strconv"
 
-	"git.ophivana.moe/security/fortify/acl"
-	"git.ophivana.moe/security/fortify/internal/fmsg"
+	"git.gensokyo.uk/security/fortify/acl"
+	"git.gensokyo.uk/security/fortify/internal/fmsg"
 )
 
 // CopyFile registers an Op that copies path dst from src.

internal/system/tmpfiles_test.go

@@ -4,7 +4,7 @@ import (
 	"strconv"
 	"testing"
 
-	"git.ophivana.moe/security/fortify/acl"
+	"git.gensokyo.uk/security/fortify/acl"
 )
 
 func TestCopyFile(t *testing.T) {

internal/system/wayland.go

@@ -5,9 +5,9 @@ import (
 	"fmt"
 	"os"
 
-	"git.ophivana.moe/security/fortify/acl"
-	"git.ophivana.moe/security/fortify/internal/fmsg"
-	"git.ophivana.moe/security/fortify/wl"
+	"git.gensokyo.uk/security/fortify/acl"
+	"git.gensokyo.uk/security/fortify/internal/fmsg"
+	"git.gensokyo.uk/security/fortify/wl"
 )
 
 // Wayland sets up a wayland socket with a security context attached.

internal/system/xhost.go

@@ -3,8 +3,8 @@ package system
 import (
 	"fmt"
 
-	"git.ophivana.moe/security/fortify/internal/fmsg"
-	"git.ophivana.moe/security/fortify/xcb"
+	"git.gensokyo.uk/security/fortify/internal/fmsg"
+	"git.gensokyo.uk/security/fortify/xcb"
 )
 
 // ChangeHosts appends an X11 ChangeHosts command Op.

ldd/exec.go

@@ -6,8 +6,8 @@ import (
 	"os/exec"
 	"strings"
 
-	"git.ophivana.moe/security/fortify/helper"
-	"git.ophivana.moe/security/fortify/helper/bwrap"
+	"git.gensokyo.uk/security/fortify/helper"
+	"git.gensokyo.uk/security/fortify/helper/bwrap"
 )
 
 func Exec(p string) ([]*Entry, error) {

ldd/ldd_test.go

@@ -6,7 +6,7 @@ import (
 	"strings"
 	"testing"
 
-	"git.ophivana.moe/security/fortify/ldd"
+	"git.gensokyo.uk/security/fortify/ldd"
 )
 
 func TestParseError(t *testing.T) {

main.go

@@ -11,13 +11,14 @@ import (
 	"sync"
 	"text/tabwriter"
 
-	"git.ophivana.moe/security/fortify/dbus"
-	"git.ophivana.moe/security/fortify/internal"
-	"git.ophivana.moe/security/fortify/internal/app"
-	"git.ophivana.moe/security/fortify/internal/fmsg"
-	"git.ophivana.moe/security/fortify/internal/linux"
-	"git.ophivana.moe/security/fortify/internal/state"
-	"git.ophivana.moe/security/fortify/internal/system"
+	"git.gensokyo.uk/security/fortify/dbus"
+	"git.gensokyo.uk/security/fortify/fst"
+	"git.gensokyo.uk/security/fortify/internal"
+	"git.gensokyo.uk/security/fortify/internal/app"
+	"git.gensokyo.uk/security/fortify/internal/fmsg"
+	"git.gensokyo.uk/security/fortify/internal/linux"
+	"git.gensokyo.uk/security/fortify/internal/state"
+	"git.gensokyo.uk/security/fortify/internal/system"
 )
 
 var (
@@ -102,7 +103,7 @@ func main() {
 		fmt.Println(license)
 		fmsg.Exit(0)
 	case "template": // print full template configuration
-		if s, err := json.MarshalIndent(app.Template(), "", "  "); err != nil {
+		if s, err := json.MarshalIndent(fst.Template(), "", "  "); err != nil {
 			fmsg.Fatalf("cannot generate template: %v", err)
 			panic("unreachable")
 		} else {
@@ -129,7 +130,7 @@ func main() {
 			fmsg.Fatal("app requires at least 1 argument")
 		}
 
-		config := new(app.Config)
+		config := new(fst.Config)
 		if f, err := os.Open(args[1]); err != nil {
 			fmsg.Fatalf("cannot access config file %q: %s", args[1], err)
 			panic("unreachable")
@@ -179,7 +180,7 @@ func main() {
 		_ = set.Parse(args[1:])
 
 		// initialise config from flags
-		config := &app.Config{
+		config := &fst.Config{
 			ID:      fid,
 			Command: set.Args(),
 		}
@@ -275,11 +276,7 @@ func main() {
 	panic("unreachable")
 }
 
-func runApp(config *app.Config) {
-	if os.SdBooted() {
-		fmsg.VPrintln("system booted with systemd as init system")
-	}
-
+func runApp(config *fst.Config) {
 	a, err := app.New(os)
 	if err != nil {
 		fmsg.Fatalf("cannot create app: %s\n", err)

options.md

@@ -36,7 +36,7 @@ package
 
 
 *Default:*
-` <derivation fortify-0.2.1> `
+` <derivation fortify-0.2.5> `
 
 
 

package.nix

@@ -14,7 +14,7 @@
 
 buildGoModule rec {
   pname = "fortify";
-  version = "0.2.3";
+  version = "0.2.5";
 
   src = ./.;
   vendorHash = null;
@@ -26,7 +26,7 @@ buildGoModule rec {
         ldflags
         ++ [
           "-X"
-          "git.ophivana.moe/security/fortify/internal.${name}=${value}"
+          "git.gensokyo.uk/security/fortify/internal.${name}=${value}"
         ]
       )
       [

test.nix

@@ -1,4 +1,5 @@
 {
+  system,
   self,
   home-manager,
   nixosTest,
@@ -31,11 +32,14 @@ nixosTest {
       services.getty.autologinUser = "alice";
 
       environment = {
-        # For glinfo and wayland-info:
         systemPackages = with pkgs; [
+          # For glinfo and wayland-info:
           mesa-demos
           wayland-utils
           alacritty
+
+          # For go tests:
+          self.devShells.${system}.fhs
         ];
 
         variables = {
@@ -73,8 +77,13 @@ nixosTest {
 
       programs.sway.enable = true;
 
-      # Need to switch to a different GPU driver than the default one (-vga std) so that Sway can launch:
-      virtualisation.qemu.options = [ "-vga none -device virtio-gpu-pci" ];
+      virtualisation.qemu.options = [
+        # Need to switch to a different GPU driver than the default one (-vga std) so that Sway can launch:
+        "-vga none -device virtio-gpu-pci"
+
+        # Increase Go test compiler performance:
+        "-smp 8"
+      ];
 
       environment.fortify = {
         enable = true;
@@ -136,10 +145,19 @@ nixosTest {
 
         retry(func)
 
+    def collect_state_ui(name):
+        swaymsg(f"exec fortify ps > '/tmp/{name}.ps'")
+        machine.copy_from_vm(f"/tmp/{name}.ps", "")
+        machine.screenshot(name)
+
     start_all()
     machine.wait_for_unit("multi-user.target")
 
-    # To check the version:
+    # Run fortify Go tests outside of nix build:
+    machine.succeed("rm -rf /tmp/src && cp -a '${self.packages.${system}.fortify.src}' /tmp/src")
+    print(machine.succeed("fortify-fhs -c '(cd /tmp/src && go generate ./... && go test ./...)'"))
+
+    # To check sway's version:
     print(machine.succeed("sway --version"))
 
     # Wait for Sway to complete startup:
@@ -164,9 +182,13 @@ nixosTest {
     wait_for_window("u0_a0@machine")
     machine.send_chars("wayland-info && touch /tmp/success-client\n")
     machine.wait_for_file("/tmp/fortify.1000/tmpdir/0/success-client")
-    machine.screenshot("foot_wayland_permissive")
+    collect_state_ui("foot_wayland_permissive")
+    # Verify acl on XDG_RUNTIME_DIR:
+    print(machine.succeed("getfacl --absolute-names --omit-header --numeric /run/user/1000 | grep 1000000"))
     machine.send_chars("exit\n")
     machine.wait_until_fails("pgrep foot")
+    # Verify acl cleanup on XDG_RUNTIME_DIR:
+    machine.wait_until_fails("getfacl --absolute-names --omit-header --numeric /run/user/1000 | grep 1000000")
 
     # Start a terminal (foot) within fortify from a terminal on workspace 4:
     machine.send_key("alt-4")
@@ -175,7 +197,7 @@ nixosTest {
     wait_for_window("u0_a0@machine")
     machine.send_chars("wayland-info && touch /tmp/success-client-term\n")
     machine.wait_for_file("/tmp/fortify.1000/tmpdir/0/success-client-term")
-    machine.screenshot("foot_wayland_permissive_term")
+    collect_state_ui("foot_wayland_permissive_term")
     machine.send_chars("exit\n")
     machine.wait_until_fails("pgrep foot")
 
@@ -184,12 +206,16 @@ nixosTest {
     wait_for_window("u0_a0@machine")
     machine.send_chars("glinfo && touch /tmp/success-client-x11\n")
     machine.wait_for_file("/tmp/fortify.1000/tmpdir/0/success-client-x11")
-    machine.screenshot("alacritty_x11_permissive")
-    machine.succeed("pkill alacritty")
+    collect_state_ui("alacritty_x11_permissive")
+    machine.send_chars("exit\n")
+    machine.wait_until_fails("pgrep alacritty")
 
     # Exit Sway and verify process exit status 0:
     swaymsg("exit", succeed=False)
     machine.wait_until_fails("pgrep -x sway")
     machine.wait_for_file("/tmp/sway-exit-ok")
+
+    # Print fortify runDir contents:
+    print(machine.succeed("find /run/user/1000/fortify"))
   '';
 }