hst: optionally disable file placement

This works around stubborn package managers.

Signed-off-by: Ophestra <cat@gensokyo.uk>

cmd/app/main.go

@@ -103,7 +103,8 @@ func main() {
 							}},
 						},
 						Username: "chronos",
-						Flags: hst.FMultiarch |
+						Flags: hst.FNoPlace |
+							hst.FMultiarch |
 							hst.FDevel |
 							hst.FUserns |
 							hst.FHostNet |

cmd/hakurei/print_test.go

@@ -64,7 +64,7 @@ func TestPrintShowInstance(t *testing.T) {
  Identity:       9 (org.chromium.Chromium)
  Enablements:    wayland, dbus, pipewire
  Groups:         video, dialout, plugdev
- Flags:          multiarch, compat, devel, userns, net, abstract, tty, mapuid, device, cover_run, runtime, tmpdir
+ Flags:          multiarch, compat, devel, userns, net, abstract, tty, mapuid, noplace, device, cover_run, runtime, tmpdir
  Home:           /data/data/org.chromium.Chromium
  Hostname:       localhost
  Path:           /run/current-system/sw/bin/chromium
@@ -161,7 +161,7 @@ App
  Identity:       9 (org.chromium.Chromium)
  Enablements:    wayland, dbus, pipewire
  Groups:         video, dialout, plugdev
- Flags:          multiarch, compat, devel, userns, net, abstract, tty, mapuid, device, cover_run, runtime, tmpdir
+ Flags:          multiarch, compat, devel, userns, net, abstract, tty, mapuid, noplace, device, cover_run, runtime, tmpdir
  Home:           /data/data/org.chromium.Chromium
  Hostname:       localhost
  Path:           /run/current-system/sw/bin/chromium
@@ -354,6 +354,7 @@ App
     "tty": true,
     "multiarch": true,
     "map_real_uid": true,
+    "noplace": true,
     "device": true,
     "cover_run": true,
     "share_runtime": true,
@@ -506,6 +507,7 @@ App
     "tty": true,
     "multiarch": true,
     "map_real_uid": true,
+    "noplace": true,
     "device": true,
     "cover_run": true,
     "share_runtime": true,
@@ -705,6 +707,7 @@ func TestPrintPs(t *testing.T) {
       "tty": true,
       "multiarch": true,
       "map_real_uid": true,
+      "noplace": true,
       "device": true,
       "cover_run": true,
       "share_runtime": true,

hst/container.go

@@ -65,6 +65,8 @@ const (
 	// Some programs fail to connect to dbus session running as a different uid,
 	// this option works around it by mapping priv-side caller uid in container.
 	FMapRealUID
+	// FNoPlace disables placement of /etc/passwd and /etc/group.
+	FNoPlace
 
 	// FDevice mount /dev/ from the init mount namespace as is in the container
 	// mount namespace.
@@ -101,6 +103,8 @@ func (flags Flags) String() string {
 		return "tty"
 	case FMapRealUID:
 		return "mapuid"
+	case FNoPlace:
+		return "noplace"
 	case FDevice:
 		return "device"
 	case FCoverRun:
@@ -197,6 +201,8 @@ type containerConfigJSON = struct {
 
 	// Corresponds to [FMapRealUID].
 	MapRealUID bool `json:"map_real_uid"`
+	// Corresponds to [FNoPlace].
+	NoPlace bool `json:"noplace,omitempty"`
 
 	// Corresponds to [FDevice].
 	Device bool `json:"device,omitempty"`
@@ -224,6 +230,7 @@ func (c *ContainerConfig) MarshalJSON() ([]byte, error) {
 		Tty:           c.Flags&FTty != 0,
 		Multiarch:     c.Flags&FMultiarch != 0,
 		MapRealUID:    c.Flags&FMapRealUID != 0,
+		NoPlace:       c.Flags&FNoPlace != 0,
 		Device:        c.Flags&FDevice != 0,
 		CoverRun:      c.Flags&FCoverRun != 0,
 		ShareRuntime:  c.Flags&FShareRuntime != 0,
@@ -266,6 +273,9 @@ func (c *ContainerConfig) UnmarshalJSON(data []byte) error {
 	if v.MapRealUID {
 		c.Flags |= FMapRealUID
 	}
+	if v.NoPlace {
+		c.Flags |= FNoPlace
+	}
 	if v.Device {
 		c.Flags |= FDevice
 	}

hst/container_test.go

@@ -21,8 +21,8 @@ func TestFlagsString(t *testing.T) {
 	}{
 		{"none", 0, "none"},
 		{"none high", hst.FAll + 1, "none"},
-		{"all", hst.FAll, "multiarch, compat, devel, userns, net, abstract, tty, mapuid, device, cover_run, runtime, tmpdir"},
+		{"all", hst.FAll, "multiarch, compat, devel, userns, net, abstract, tty, mapuid, noplace, device, cover_run, runtime, tmpdir"},
-		{"all high", math.MaxUint, "multiarch, compat, devel, userns, net, abstract, tty, mapuid, device, cover_run, runtime, tmpdir"},
+		{"all high", math.MaxUint, "multiarch, compat, devel, userns, net, abstract, tty, mapuid, noplace, device, cover_run, runtime, tmpdir"},
 	}
 	for _, tc := range testCases {
 		t.Run(tc.name, func(t *testing.T) {
@@ -53,7 +53,7 @@ func TestContainerConfig(t *testing.T) {
 		{"hostnet hostabstract mapuid", &hst.ContainerConfig{Flags: hst.FHostNet | hst.FHostAbstract | hst.FMapRealUID},
 			`{"env":null,"filesystem":null,"shell":null,"home":null,"args":null,"host_net":true,"host_abstract":true,"map_real_uid":true}`},
 		{"all", &hst.ContainerConfig{Flags: hst.FAll},
-			`{"env":null,"filesystem":null,"shell":null,"home":null,"args":null,"seccomp_compat":true,"devel":true,"userns":true,"host_net":true,"host_abstract":true,"tty":true,"multiarch":true,"map_real_uid":true,"device":true,"cover_run":true,"share_runtime":true,"share_tmpdir":true}`},
+			`{"env":null,"filesystem":null,"shell":null,"home":null,"args":null,"seccomp_compat":true,"devel":true,"userns":true,"host_net":true,"host_abstract":true,"tty":true,"multiarch":true,"map_real_uid":true,"noplace":true,"device":true,"cover_run":true,"share_runtime":true,"share_tmpdir":true}`},
 	}
 
 	for _, tc := range testCases {

hst/hst_test.go

@@ -244,6 +244,7 @@ func TestTemplate(t *testing.T) {
 		"tty": true,
 		"multiarch": true,
 		"map_real_uid": true,
+		"noplace": true,
 		"device": true,
 		"cover_run": true,
 		"share_runtime": true,

internal/outcome/run_test.go

@@ -143,10 +143,6 @@ func TestOutcomeRun(t *testing.T) {
 				// spTmpdirOp
 				Bind(m("/tmp/hakurei.0/tmpdir/9"), fhs.AbsTmp, std.BindWritable).
 
-				// spAccountOp
-				Place(m("/etc/passwd"), []byte("chronos:x:1971:100:Hakurei:/data/data/org.chromium.Chromium:/run/current-system/sw/bin/zsh\n")).
-				Place(m("/etc/group"), []byte("hakurei:x:100:\n")).
-
 				// spWaylandOp
 				Bind(m("/tmp/hakurei.0/aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa/wayland"), m("/run/user/1971/wayland-0"), 0).
 
@@ -453,7 +449,7 @@ func TestOutcomeRun(t *testing.T) {
 
 				Path: m("/nix/store/yqivzpzzn7z5x0lq9hmbzygh45d8rhqd-chromium-start"),
 
-				Flags: hst.FUserns | hst.FHostNet | hst.FMapRealUID | hst.FShareRuntime | hst.FShareTmpdir,
+				Flags: hst.FUserns | hst.FHostNet | hst.FMapRealUID | hst.FNoPlace | hst.FShareRuntime | hst.FShareTmpdir,
 			},
 			SystemBus: &hst.BusConfig{
 				Talk:   []string{"org.bluez", "org.freedesktop.Avahi", "org.freedesktop.UPower"},
@@ -548,8 +544,6 @@ func TestOutcomeRun(t *testing.T) {
 				Tmpfs(m("/run/user/"), xdgRuntimeDirSize, 0755).
 				Bind(m("/tmp/hakurei.0/runtime/1"), m("/run/user/1971"), std.BindWritable).
 				Bind(m("/tmp/hakurei.0/tmpdir/1"), m("/tmp/"), std.BindWritable).
-				Place(m("/etc/passwd"), []byte("u0_a1:x:1971:100:Hakurei:/var/lib/persist/module/hakurei/0/1:/run/current-system/sw/bin/zsh\n")).
-				Place(m("/etc/group"), []byte("hakurei:x:100:\n")).
 				Bind(m("/run/user/1971/wayland-0"), m("/run/user/1971/wayland-0"), 0).
 				Bind(m("/tmp/hakurei.0/8e2c76b066dabe574cf073bdb46eb5c1/pipewire"), m("/run/user/1971/pipewire-0"), 0).
 				Bind(m("/tmp/hakurei.0/8e2c76b066dabe574cf073bdb46eb5c1/bus"), m("/run/user/1971/bus"), 0).

internal/outcome/shim_test.go

@@ -78,10 +78,6 @@ func TestShimEntrypoint(t *testing.T) {
 			// spTmpdirOp
 			Bind(m("/tmp/hakurei.10/tmpdir/9999"), fhs.AbsTmp, std.BindWritable).
 
-			// spAccountOp
-			Place(m("/etc/passwd"), []byte("chronos:x:1000:100:Hakurei:/data/data/org.chromium.Chromium:/run/current-system/sw/bin/zsh\n")).
-			Place(m("/etc/group"), []byte("hakurei:x:100:\n")).
-
 			// spWaylandOp
 			Bind(m("/tmp/hakurei.10/aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa/wayland"), m("/run/user/1000/wayland-0"), 0).
 

internal/outcome/spaccount.go

@@ -6,6 +6,7 @@ import (
 	"syscall"
 
 	"hakurei.app/fhs"
+	"hakurei.app/hst"
 	"hakurei.app/internal/validate"
 )
 
@@ -41,6 +42,7 @@ func (s spAccountOp) toContainer(state *outcomeStateParams) error {
 	state.env["USER"] = username
 	state.env["SHELL"] = state.Container.Shell.String()
 
+	if state.Container.Flags&hst.FNoPlace == 0 {
 		state.params.
 			Place(fhs.AbsEtc.Append("passwd"),
 				[]byte(username+":x:"+
@@ -51,6 +53,7 @@ func (s spAccountOp) toContainer(state *outcomeStateParams) error {
 					state.Container.Shell.String()+"\n")).
 			Place(fhs.AbsEtc.Append("group"),
 				[]byte("hakurei:x:"+state.mapgid.String()+":\n"))
+	}
 
 	return nil
 }

internal/outcome/spaccount_test.go

@@ -38,6 +38,7 @@ func TestSpAccountOp(t *testing.T) {
 		{"success fallback username", func(bool, bool) outcomeOp { return spAccountOp{} }, func() *hst.Config {
 			c := hst.Template()
 			c.Container.Username = ""
+			c.Container.Flags = hst.FMapRealUID
 			return c
 		}, nil, []stub.Call{
 			// this op performs basic validation and does not make calls during toSystem
@@ -60,9 +61,7 @@ func TestSpAccountOp(t *testing.T) {
 			// this op configures the container state and does not make calls during toContainer
 		}, &container.Params{
 			Dir: config.Container.Home,
-			Ops: new(container.Ops).
+			Ops: new(container.Ops),
-				Place(m("/etc/passwd"), []byte("chronos:x:1000:100:Hakurei:/data/data/org.chromium.Chromium:/run/current-system/sw/bin/zsh\n")).
-				Place(m("/etc/group"), []byte("hakurei:x:100:\n")),
 		}, paramsWantEnv(config, map[string]string{
 			"HOME":  config.Container.Home.String(),
 			"USER":  config.Container.Username,