web_control_linux.go RawHistoryFolder

1//go:build linux
2
3package app
4
5import (
6	"crypto/sha256"
7	"fmt"
8	"net"
9	"os"
10	"path/filepath"
11	"syscall"
12
13	"github.com/bnema/vev/internal/platform"
14)
15
16// Linux abstract sockets have no filesystem artifact. Peer credentials, not
17// the discoverability of this name, protect the local control interface.
18func webControlAddress() string {
19	path, _ := filepath.Abs(platform.StateDir())
20	return fmt.Sprintf("@vev-web-%d-%x", os.Geteuid(), sha256.Sum256([]byte(path)))
21}
22
23func sameWebUID(conn *net.UnixConn) bool {
24	raw, err := conn.SyscallConn()
25	if err != nil {
26		return false
27	}
28	var credential *syscall.Ucred
29	var peerErr error
30	err = raw.Control(func(fd uintptr) {
31		credential, peerErr = syscall.GetsockoptUcred(int(fd), syscall.SOL_SOCKET, syscall.SO_PEERCRED)
32	})
33	return err == nil && peerErr == nil && credential != nil && credential.Uid == uint32(os.Geteuid())
34}
35
36func bindWebControl() (*net.UnixListener, error) {
37	return net.ListenUnix("unix", &net.UnixAddr{Name: webControlAddress(), Net: "unix"})
38}