1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
|
package main
import (
"errors"
"flag"
"fmt"
"io/fs"
"os"
"path"
"strconv"
"syscall"
"git.ophivana.moe/cat/fortify/internal/acl"
"git.ophivana.moe/cat/fortify/internal/app"
"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/xcb"
)
var (
Version = "impure"
a *app.App
)
func tryVersion() {
if printVersion {
fmt.Println(Version)
os.Exit(0)
}
}
const (
term = "TERM"
display = "DISPLAY"
// https://manpages.debian.org/experimental/libwayland-doc/wl_display_connect.3.en.html
waylandDisplay = "WAYLAND_DISPLAY"
)
func main() {
flag.Parse()
// launcher payload early exit
app.Early(printVersion)
// version/license command early exit
tryVersion()
tryLicense()
system.Retrieve(flagVerbose)
a = app.New(userName, flag.Args())
state.Set(*a.User, a.Command(), a.UID())
// ensure RunDir (e.g. `/run/user/%d/fortify`)
if err := os.Mkdir(system.V.RunDir, 0700); err != nil && !errors.Is(err, fs.ErrExist) {
state.Fatal("Error creating runtime directory:", err)
}
// state query command early exit
state.Early()
// ensure Share (e.g. `/tmp/fortify.%d`)
// acl is unnecessary as this directory is world executable
if err := os.Mkdir(system.V.Share, 0701); err != nil && !errors.Is(err, fs.ErrExist) {
state.Fatal("Error creating shared directory:", err)
}
// warn about target user home directory ownership
if stat, err := os.Stat(a.HomeDir); err != nil {
if system.V.Verbose {
switch {
case errors.Is(err, fs.ErrPermission):
fmt.Printf("User %s home directory %s is not accessible", a.Username, a.HomeDir)
case errors.Is(err, fs.ErrNotExist):
fmt.Printf("User %s home directory %s does not exist", a.Username, a.HomeDir)
default:
fmt.Printf("Error stat user %s home directory %s: %s", a.Username, a.HomeDir, err)
}
}
return
} else {
// FreeBSD: not cross-platform
if u := strconv.Itoa(int(stat.Sys().(*syscall.Stat_t).Uid)); u != a.Uid {
fmt.Printf("User %s home directory %s has incorrect ownership (expected UID %s, found %s)", a.Username, a.HomeDir, a.Uid, u)
}
}
// ensure runtime directory ACL (e.g. `/run/user/%d`)
if s, err := os.Stat(system.V.Runtime); err != nil {
if errors.Is(err, fs.ErrNotExist) {
state.Fatal("Runtime directory does not exist")
}
state.Fatal("Error accessing runtime directory:", err)
} else if !s.IsDir() {
state.Fatal(fmt.Sprintf("Path '%s' is not a directory", system.V.Runtime))
} else {
if err = acl.UpdatePerm(system.V.Runtime, a.UID(), acl.Execute); err != nil {
state.Fatal("Error preparing runtime dir:", err)
} else {
state.RegisterRevertPath(system.V.Runtime)
}
if system.V.Verbose {
fmt.Printf("Runtime data dir '%s' configured\n", system.V.Runtime)
}
}
// ensure Wayland socket ACL (e.g. `/run/user/%d/wayland-%d`)
if w, ok := os.LookupEnv(waylandDisplay); !ok {
if system.V.Verbose {
fmt.Println("Wayland: WAYLAND_DISPLAY not set, skipping")
}
} else {
// add environment variable for new process
wp := path.Join(system.V.Runtime, 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)
} else {
state.RegisterRevertPath(wp)
}
if system.V.Verbose {
fmt.Printf("Wayland socket '%s' configured\n", w)
}
}
// discovery X11 and grant user permission via the `ChangeHosts` command
if d, ok := os.LookupEnv(display); !ok {
if system.V.Verbose {
fmt.Println("X11: DISPLAY not set, skipping")
}
} else {
// add environment variable for new process
a.AppendEnv(display, d)
if system.V.Verbose {
fmt.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)
} else {
state.XcbActionComplete()
}
}
// ensure PulseAudio directory ACL (e.g. `/run/user/%d/pulse`)
pulse := path.Join(system.V.Runtime, "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)
}
if mustPulse {
state.Fatal("PulseAudio is unavailable")
}
if system.V.Verbose {
fmt.Printf("PulseAudio dir '%s' not found, skipping\n", 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)
} else {
state.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")
}
state.Fatal("Error accessing PulseAudio socket:", err)
} else {
if m := s.Mode(); m&0o006 != 0o006 {
state.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")
a.AppendEnv(util.PulseCookie, pulseCookieFinal)
if system.V.Verbose {
fmt.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)
}
if err = acl.UpdatePerm(pulseCookieFinal, a.UID(), acl.Read); err != nil {
state.Fatal("Error publishing PulseAudio cookie:", err)
} else {
state.RegisterRevertPath(pulseCookieFinal)
}
if system.V.Verbose {
fmt.Printf("PulseAudio dir '%s' configured\n", pulse)
}
}
// pass $TERM to launcher
if t, ok := os.LookupEnv(term); ok {
a.AppendEnv(term, t)
}
a.Run()
}
|
