package main import ( "encoding/hex" "os" "strings" "golang.org/x/crypto/ssh/terminal" "github.com/rfjakob/gocryptfs/internal/cryptocore" "github.com/rfjakob/gocryptfs/internal/tlog" ) // printMasterKey - remind the user that he should store the master key in // a safe place func printMasterKey(key []byte) { if !terminal.IsTerminal(int(os.Stdout.Fd())) { // We don't want the master key to end up in a log file tlog.Info.Printf("Not running on a terminal, suppressing master key display\n") return } h := hex.EncodeToString(key) var hChunked string // Try to make it less scary by splitting it up in chunks for i := 0; i < len(h); i += 8 { hChunked += h[i : i+8] if i < 52 { hChunked += "-" } if i == 24 { hChunked += "\n " } } tlog.Info.Printf(` Your master key is: %s If the gocryptfs.conf file becomes corrupted or you ever forget your password, there is only one hope for recovery: The master key. Print it to a piece of paper and store it in a drawer. Use "-q" to suppress this message. `, tlog.ColorGrey+hChunked+tlog.ColorReset) } // parseMasterKey - Parse a hex-encoded master key that was passed on the command line // Calls os.Exit on failure func parseMasterKey(masterkey string) []byte { masterkey = strings.Replace(masterkey, "-", "", -1) key, err := hex.DecodeString(masterkey) if err != nil { tlog.Fatal.Printf("Could not parse master key: %v", err) os.Exit(1) } if len(key) != cryptocore.KeyLen { tlog.Fatal.Printf("Master key has length %d but we require length %d", len(key), cryptocore.KeyLen) os.Exit(1) } tlog.Info.Printf("Using explicit master key.") tlog.Info.Printf(tlog.ColorYellow + "THE MASTER KEY IS VISIBLE VIA \"ps ax\" AND MAY BE STORED IN YOUR SHELL HISTORY!\n" + "ONLY USE THIS MODE FOR EMERGENCIES." + tlog.ColorReset) return key }