package main import ( "flag" "fmt" "os" "os/exec" "os/signal" "path/filepath" "runtime" "runtime/pprof" "syscall" "time" "github.com/rfjakob/gocryptfs/cryptfs" "github.com/rfjakob/gocryptfs/pathfs_frontend" "github.com/hanwen/go-fuse/fuse" "github.com/hanwen/go-fuse/fuse/nodefs" "github.com/hanwen/go-fuse/fuse/pathfs" ) const ( PROGRAM_NAME = "gocryptfs" // Exit codes ERREXIT_USAGE = 1 ERREXIT_MOUNT = 3 ERREXIT_CIPHERDIR = 6 ERREXIT_INIT = 7 ERREXIT_LOADCONF = 8 ERREXIT_PASSWORD = 9 ERREXIT_MOUNTPOINT = 10 ) var GitVersion = "[version not set - please compile using ./build.bash]" func initDir(dirArg string) { dir, _ := filepath.Abs(dirArg) err := checkDirEmpty(dir) if err != nil { fmt.Printf("Error: \"%s\": %v\n", dirArg, err) os.Exit(ERREXIT_INIT) } confName := filepath.Join(dir, cryptfs.ConfDefaultName) fmt.Printf("Choose a password for protecting your files.\n") password := readPasswordTwice() err = cryptfs.CreateConfFile(confName, password) if err != nil { fmt.Println(err) os.Exit(ERREXIT_INIT) } fmt.Printf("The filesystem is now ready for mounting.\n") os.Exit(0) } func usageText() { fmt.Printf("Usage: %s [OPTIONS] CIPHERDIR MOUNTPOINT\n", PROGRAM_NAME) fmt.Printf("\nOptions:\n") flag.PrintDefaults() } func main() { runtime.GOMAXPROCS(4) // Parse command line arguments var debug, init, zerokey, fusedebug, openssl, passwd, foreground, version bool var masterkey, mountpoint, cipherdir string flag.Usage = usageText flag.BoolVar(&debug, "debug", false, "Enable debug output") flag.BoolVar(&fusedebug, "fusedebug", false, "Enable fuse library debug output") flag.BoolVar(&init, "init", false, "Initialize encrypted directory") flag.BoolVar(&zerokey, "zerokey", false, "Use all-zero dummy master key") flag.BoolVar(&openssl, "openssl", true, "Use OpenSSL instead of built-in Go crypto") flag.BoolVar(&passwd, "passwd", false, "Change password") flag.BoolVar(&foreground, "f", false, "Stay in the foreground") flag.BoolVar(&version, "version", false, "Print version and exit") flag.StringVar(&masterkey, "masterkey", "", "Mount with explicit master key") var cpuprofile = flag.String("cpuprofile", "", "Write cpu profile to specified file") flag.Parse() if version { fmt.Printf("%s %s; ", PROGRAM_NAME, GitVersion) fmt.Printf("on-disk format %d\n", cryptfs.HEADER_CURRENT_VERSION) os.Exit(0) } if !foreground { daemonize() // does not return } if *cpuprofile != "" { f, err := os.Create(*cpuprofile) if err != nil { fmt.Println(err) os.Exit(ERREXIT_INIT) } fmt.Printf("Writing CPU profile to %s\n", *cpuprofile) pprof.StartCPUProfile(f) defer pprof.StopCPUProfile() } if debug { cryptfs.Debug.Enable() cryptfs.Debug.Printf("Debug output enabled\n") } if openssl == false { fmt.Printf("Openssl disabled\n") } if init { if flag.NArg() != 1 { fmt.Printf("Usage: %s --init CIPHERDIR\n", PROGRAM_NAME) os.Exit(ERREXIT_USAGE) } initDir(flag.Arg(0)) // does not return } if passwd { if flag.NArg() != 1 { fmt.Printf("Usage: %s --passwd CIPHERDIR\n", PROGRAM_NAME) os.Exit(ERREXIT_USAGE) } } else { // Normal mount if flag.NArg() < 2 { usageText() os.Exit(ERREXIT_USAGE) } mountpoint, _ = filepath.Abs(flag.Arg(1)) err := checkDirEmpty(mountpoint) if err != nil { fmt.Printf("Invalid MOUNTPOINT: %v\n", err) os.Exit(ERREXIT_MOUNTPOINT) } } cipherdir, _ = filepath.Abs(flag.Arg(0)) err := checkDir(cipherdir) if err != nil { fmt.Printf("Invalid CIPHERDIR: %v\n", err) os.Exit(ERREXIT_CIPHERDIR) } var cf *cryptfs.ConfFile var currentPassword string key := make([]byte, cryptfs.KEY_LEN) if zerokey { fmt.Printf("Zerokey mode active: using all-zero dummy master key.\n") } else if len(masterkey) > 0 { key = parseMasterKey(masterkey) fmt.Printf("Using explicit master key.\n") } else { cfname := filepath.Join(cipherdir, cryptfs.ConfDefaultName) _, err = os.Stat(cfname) if err != nil { fmt.Printf("Error: %s not found in CIPHERDIR\n", cryptfs.ConfDefaultName) fmt.Printf("Please run \"%s --init %s\" first\n", os.Args[0], flag.Arg(0)) os.Exit(ERREXIT_LOADCONF) } if passwd == true { fmt.Printf("Old password: ") } else { fmt.Printf("Password: ") } currentPassword = readPassword() fmt.Printf("\nDecrypting master key... ") cryptfs.Warn.Disable() // Silence DecryptBlock() error messages on incorrect password key, cf, err = cryptfs.LoadConfFile(cfname, currentPassword) cryptfs.Warn.Enable() if err != nil { fmt.Println(err) os.Exit(ERREXIT_LOADCONF) } fmt.Printf("done.\n") } if passwd == true { fmt.Printf("Please enter the new password.\n") newPassword := readPasswordTwice() if newPassword == currentPassword { fmt.Printf("New and old passwords are identical\n") os.Exit(ERREXIT_PASSWORD) } cf.EncryptKey(key, newPassword) err := cf.WriteFile() if err != nil { fmt.Println(err) os.Exit(ERREXIT_INIT) } fmt.Printf("Password changed.\n") os.Exit(0) } srv := pathfsFrontend(key, cipherdir, mountpoint, fusedebug, openssl) if zerokey == false && len(masterkey) == 0 { printMasterKey(key) } else if zerokey == true { fmt.Printf("ZEROKEY MODE PROVIDES NO SECURITY AT ALL AND SHOULD ONLY BE USED FOR TESTING.\n") } else if len(masterkey) > 0 { fmt.Printf("THE MASTER KEY IS VISIBLE VIA \"ps -auxwww\", ONLY USE THIS MODE FOR EMERGENCIES.\n") } fmt.Println("Filesystem ready.") // Send notification to our parent sendUsr1() // Wait for SIGING in the background and unmount ourselves if we get it // This prevents a dangling "Transport endpoint is not connected" mountpoint handleSigint(srv, mountpoint) // Jump into server loop. Returns when it gets an umount request from the kernel. srv.Serve() // main returns with code 0 } func pathfsFrontend(key []byte, cipherdir string, mountpoint string, debug bool, openssl bool) *fuse.Server { finalFs := pathfs_frontend.NewFS(key, cipherdir, openssl) pathFsOpts := &pathfs.PathNodeFsOptions{ClientInodes: true} pathFs := pathfs.NewPathNodeFs(finalFs, pathFsOpts) fuseOpts := &nodefs.Options{ // These options are to be compatible with libfuse defaults, // making benchmarking easier. NegativeTimeout: time.Second, AttrTimeout: time.Second, EntryTimeout: time.Second, } conn := nodefs.NewFileSystemConnector(pathFs.Root(), fuseOpts) var mOpts fuse.MountOptions mOpts.AllowOther = false // Set values shown in "df -T" and friends // First column, "Filesystem" mOpts.Options = append(mOpts.Options, "fsname="+cipherdir) // Second column, "Type", will be shown as "fuse." + Name mOpts.Name = "gocryptfs" srv, err := fuse.NewServer(conn.RawFS(), mountpoint, &mOpts) if err != nil { fmt.Printf("Mount failed: %v", err) os.Exit(ERREXIT_MOUNT) } srv.SetDebug(debug) return srv } func handleSigint(srv *fuse.Server, mountpoint string) { ch := make(chan os.Signal, 1) signal.Notify(ch, os.Interrupt) signal.Notify(ch, syscall.SIGTERM) go func() { <-ch err := srv.Unmount() if err != nil { fmt.Print(err) fmt.Printf("Trying lazy unmount\n") cmd := exec.Command("fusermount", "-u", "-z", mountpoint) cmd.Stdout = os.Stdout cmd.Stderr = os.Stderr cmd.Run() } os.Exit(1) }() }