libgocryptfs/main.go
Daniel Theophanes 439dea1b19 Use existing build information for version if not embedded with build script
Go1.12 introduced BuildInfo which embeds build information. It does
not embed build date to facilitate reproducable builds by default.
If build information is embedded from build script, use the information
provided by the Go build system.
2022-12-29 14:42:13 +01:00

387 lines
11 KiB
Go

// gocryptfs is an encrypted overlay filesystem written in Go.
// See README.md ( https://github.com/rfjakob/gocryptfs/blob/master/README.md )
// and the official website ( https://nuetzlich.net/gocryptfs/ ) for details.
package main
import (
"fmt"
"log"
"os"
"path/filepath"
"runtime"
"runtime/debug"
"strconv"
"strings"
"github.com/hanwen/go-fuse/v2/fuse"
"github.com/rfjakob/gocryptfs/v2/internal/configfile"
"github.com/rfjakob/gocryptfs/v2/internal/contentenc"
"github.com/rfjakob/gocryptfs/v2/internal/exitcodes"
"github.com/rfjakob/gocryptfs/v2/internal/fido2"
"github.com/rfjakob/gocryptfs/v2/internal/readpassword"
"github.com/rfjakob/gocryptfs/v2/internal/speed"
"github.com/rfjakob/gocryptfs/v2/internal/stupidgcm"
"github.com/rfjakob/gocryptfs/v2/internal/tlog"
)
// GitVersion is the gocryptfs version according to git, set by build.bash
var GitVersion = "[GitVersion not set - please compile using ./build.bash]"
// GitVersionFuse is the go-fuse library version, set by build.bash
var GitVersionFuse = "[GitVersionFuse not set - please compile using ./build.bash]"
// BuildDate is a date string like "2017-09-06", set by build.bash
var BuildDate = "0000-00-00"
// raceDetector is set to true by race.go if we are compiled with "go build -race"
var raceDetector bool
func initGIT() {
bi, ok := debug.ReadBuildInfo()
if !ok {
return
}
if strings.HasPrefix(GitVersion, `[`) {
GitVersion = bi.Main.Version
var gitDate string
var gitDirty bool
for _, item := range bi.Settings {
switch item.Key {
case "vcs.revision":
GitVersion = item.Value
case "vcs.time":
gitDate = item.Value
gitDate = strings.Map(func(r rune) rune {
switch {
case r >= '0' && r <= '9':
return r
default:
return -1
}
}, gitDate)
case "vcs.modified":
gitDirty, _ = strconv.ParseBool(item.Value)
}
}
if len(gitDate) > 0 {
GitVersion = gitDate + "-" + GitVersion
}
if gitDirty {
GitVersion = GitVersion + " (dirty)"
}
}
const fuseModule = `github.com/hanwen/go-fuse/v2`
if strings.HasPrefix(GitVersionFuse, `[`) {
for _, item := range bi.Deps {
if item.Path == fuseModule {
GitVersionFuse = item.Version
}
}
}
}
// loadConfig loads the config file `args.config` and decrypts the masterkey,
// or gets via the `-masterkey` or `-zerokey` command line options, if specified.
func loadConfig(args *argContainer) (masterkey []byte, cf *configfile.ConfFile, err error) {
// First check if the file can be read at all.
cf, err = configfile.Load(args.config)
if err != nil {
tlog.Fatal.Printf("Cannot open config file: %v", err)
return nil, nil, err
}
// The user may have passed the master key on the command line (probably because
// he forgot the password).
masterkey = handleArgsMasterkey(args)
if masterkey != nil {
return masterkey, cf, nil
}
var pw []byte
if cf.IsFeatureFlagSet(configfile.FlagFIDO2) {
if args.fido2 == "" {
tlog.Fatal.Printf("Masterkey encrypted using FIDO2 token; need to use the --fido2 option.")
return nil, nil, exitcodes.NewErr("", exitcodes.Usage)
}
pw = fido2.Secret(args.fido2, cf.FIDO2.CredentialID, cf.FIDO2.HMACSalt)
} else {
pw, err = readpassword.Once([]string(args.extpass), []string(args.passfile), "")
if err != nil {
tlog.Fatal.Println(err)
return nil, nil, exitcodes.NewErr("", exitcodes.ReadPassword)
}
}
tlog.Info.Println("Decrypting master key")
masterkey, err = cf.DecryptMasterKey(pw)
for i := range pw {
pw[i] = 0
}
if err != nil {
tlog.Fatal.Println(err)
return nil, nil, err
}
return masterkey, cf, nil
}
// changePassword - change the password of config file "filename"
// Does not return (calls os.Exit both on success and on error).
func changePassword(args *argContainer) {
var confFile *configfile.ConfFile
{
var masterkey []byte
var err error
masterkey, confFile, err = loadConfig(args)
if err != nil {
exitcodes.Exit(err)
}
if len(masterkey) == 0 {
log.Panic("empty masterkey")
}
if confFile.IsFeatureFlagSet(configfile.FlagFIDO2) {
tlog.Fatal.Printf("Password change is not supported on FIDO2-enabled filesystems.")
os.Exit(exitcodes.Usage)
}
tlog.Info.Println("Please enter your new password.")
newPw, err := readpassword.Twice([]string(args.extpass), []string(args.passfile))
if err != nil {
tlog.Fatal.Println(err)
os.Exit(exitcodes.ReadPassword)
}
logN := confFile.ScryptObject.LogN()
if args._explicitScryptn {
logN = args.scryptn
}
confFile.EncryptKey(masterkey, newPw, logN)
for i := range newPw {
newPw[i] = 0
}
for i := range masterkey {
masterkey[i] = 0
}
// masterkey and newPw run out of scope here
}
// Are we resetting the password without knowing the old one using
// "-masterkey"?
if args.masterkey != "" {
bak := args.config + ".bak"
err := os.Link(args.config, bak)
if err != nil {
tlog.Fatal.Printf("Could not create backup file: %v", err)
os.Exit(exitcodes.Init)
}
tlog.Info.Printf(tlog.ColorGrey+
"A copy of the old config file has been created at %q.\n"+
"Delete it after you have verified that you can access your files with the new password."+
tlog.ColorReset, bak)
}
err := confFile.WriteFile()
if err != nil {
tlog.Fatal.Println(err)
os.Exit(exitcodes.WriteConf)
}
tlog.Info.Printf(tlog.ColorGreen + "Password changed." + tlog.ColorReset)
}
// printVersion prints a version string like this:
// gocryptfs v1.7-32-gcf99cfd; go-fuse v1.0.0-174-g22a9cb9; 2019-05-12 go1.12 linux/amd64
func printVersion() {
initGIT()
var tagsSlice []string
if stupidgcm.BuiltWithoutOpenssl {
tagsSlice = append(tagsSlice, "without_openssl")
}
tags := ""
if tagsSlice != nil {
tags = " " + strings.Join(tagsSlice, " ")
}
built := fmt.Sprintf("%s %s", BuildDate, runtime.Version())
if raceDetector {
built += " -race"
}
fmt.Printf("%s %s%s; go-fuse %s; %s %s/%s\n",
tlog.ProgramName, GitVersion, tags, GitVersionFuse, built,
runtime.GOOS, runtime.GOARCH)
}
func main() {
mxp := runtime.GOMAXPROCS(0)
if mxp < 4 && os.Getenv("GOMAXPROCS") == "" {
// On a 2-core machine, setting maxprocs to 4 gives 10% better performance.
// But don't override an explicitly set GOMAXPROCS env variable.
runtime.GOMAXPROCS(4)
}
// mount(1) unsets PATH. Since exec.Command does not handle this case, we set
// PATH to a default value if it's empty or unset.
if os.Getenv("PATH") == "" {
os.Setenv("PATH", "/usr/sbin:/usr/bin:/sbin:/bin")
}
// Show microseconds in go-fuse debug output (-fusedebug)
log.SetFlags(log.Lmicroseconds)
var err error
// Parse all command-line options (i.e. arguments starting with "-")
// into "args". Path arguments are parsed below.
args := parseCliOpts(os.Args)
// Fork a child into the background if "-fg" is not set AND we are mounting
// a filesystem. The child will do all the work.
if !args.fg && flagSet.NArg() == 2 {
ret := forkChild()
os.Exit(ret)
}
if args.debug {
tlog.Debug.Enabled = true
}
tlog.Debug.Printf("cli args: %q", os.Args)
// "-v"
if args.version {
tlog.Debug.Printf("openssl=%v\n", args.openssl)
tlog.Debug.Printf("on-disk format %d\n", contentenc.CurrentVersion)
printVersion()
os.Exit(0)
}
// "-hh"
if args.hh {
helpLong()
os.Exit(0)
}
// "-speed"
if args.speed {
printVersion()
speed.Run()
os.Exit(0)
}
if args.wpanic {
tlog.Warn.Wpanic = true
tlog.Debug.Printf("Panicking on warnings")
}
// Every operation below requires CIPHERDIR. Exit if we don't have it.
if flagSet.NArg() == 0 {
if flagSet.NFlag() == 0 {
// Naked call to "gocryptfs". Just print the help text.
helpShort()
} else {
// The user has passed some flags, but CIPHERDIR is missing. State
// what is wrong.
tlog.Fatal.Printf("CIPHERDIR argument is missing")
}
os.Exit(exitcodes.Usage)
}
// Check that CIPHERDIR exists
args.cipherdir, _ = filepath.Abs(flagSet.Arg(0))
err = isDir(args.cipherdir)
if err != nil {
tlog.Fatal.Printf("Invalid cipherdir: %v", err)
os.Exit(exitcodes.CipherDir)
}
// "-q"
if args.quiet {
tlog.Info.Enabled = false
}
// "-reverse" implies "-aessiv"
if args.reverse {
args.aessiv = true
} else {
if args.exclude != nil {
tlog.Fatal.Printf("-exclude only works in reverse mode")
os.Exit(exitcodes.ExcludeError)
}
}
// "-config"
if args.config != "" {
args.config, err = filepath.Abs(args.config)
if err != nil {
tlog.Fatal.Printf("Invalid \"-config\" setting: %v", err)
os.Exit(exitcodes.Init)
}
tlog.Info.Printf("Using config file at custom location %s", args.config)
args._configCustom = true
} else if args.reverse {
args.config = filepath.Join(args.cipherdir, configfile.ConfReverseName)
} else {
args.config = filepath.Join(args.cipherdir, configfile.ConfDefaultName)
}
// "-force_owner"
if args.force_owner != "" {
var uidNum, gidNum int64
ownerPieces := strings.SplitN(args.force_owner, ":", 2)
if len(ownerPieces) != 2 {
tlog.Fatal.Printf("force_owner must be in form UID:GID")
os.Exit(exitcodes.Usage)
}
uidNum, err = strconv.ParseInt(ownerPieces[0], 0, 32)
if err != nil || uidNum < 0 {
tlog.Fatal.Printf("force_owner: Unable to parse UID %v as positive integer", ownerPieces[0])
os.Exit(exitcodes.Usage)
}
gidNum, err = strconv.ParseInt(ownerPieces[1], 0, 32)
if err != nil || gidNum < 0 {
tlog.Fatal.Printf("force_owner: Unable to parse GID %v as positive integer", ownerPieces[1])
os.Exit(exitcodes.Usage)
}
args._forceOwner = &fuse.Owner{Uid: uint32(uidNum), Gid: uint32(gidNum)}
}
// "-cpuprofile"
if args.cpuprofile != "" {
onExitFunc := setupCpuprofile(args.cpuprofile)
defer onExitFunc()
}
// "-memprofile"
if args.memprofile != "" {
onExitFunc := setupMemprofile(args.memprofile)
defer onExitFunc()
}
// "-trace"
if args.trace != "" {
onExitFunc := setupTrace(args.trace)
defer onExitFunc()
}
if args.cpuprofile != "" || args.memprofile != "" || args.trace != "" {
tlog.Info.Printf("Note: You must unmount gracefully, otherwise the profile file(s) will stay empty!\n")
}
// Operation flags
nOps := countOpFlags(&args)
if nOps == 0 {
// Default operation: mount.
if flagSet.NArg() != 2 {
prettyArgs := prettyArgs()
tlog.Info.Printf("Wrong number of arguments (have %d, want 2). You passed: %s",
flagSet.NArg(), prettyArgs)
tlog.Fatal.Printf("Usage: %s [OPTIONS] CIPHERDIR MOUNTPOINT [-o COMMA-SEPARATED-OPTIONS]", tlog.ProgramName)
os.Exit(exitcodes.Usage)
}
doMount(&args)
// Don't call os.Exit to give deferred functions a chance to run
return
}
if nOps > 1 {
tlog.Fatal.Printf("At most one of -info, -init, -passwd, -fsck is allowed")
os.Exit(exitcodes.Usage)
}
if flagSet.NArg() != 1 {
tlog.Fatal.Printf("The options -info, -init, -passwd, -fsck take exactly one argument, %d given",
flagSet.NArg())
os.Exit(exitcodes.Usage)
}
// "-info"
if args.info {
info(args.config)
os.Exit(0)
}
// "-init"
if args.init {
initDir(&args)
os.Exit(0)
}
// "-passwd"
if args.passwd {
changePassword(&args)
os.Exit(0)
}
// "-fsck"
if args.fsck {
code := fsck(&args)
os.Exit(code)
}
}