Public Release

cmd/nebula-cert/main.go

@@ -0,0 +1,137 @@
+package main
+
+import (
+	"flag"
+	"fmt"
+	"io"
+	"os"
+)
+
+var Build string
+
+type helpError struct {
+	s string
+}
+
+func (he *helpError) Error() string {
+	return he.s
+}
+
+func newHelpErrorf(s string, v ...interface{}) error {
+	return &helpError{s: fmt.Sprintf(s, v...)}
+}
+
+func main() {
+	flag.Usage = func() {
+		help("", os.Stderr)
+		os.Exit(1)
+	}
+
+	printVersion := flag.Bool("version", false, "Print version")
+	flagHelp := flag.Bool("help", false, "Print command line usage")
+	flagH := flag.Bool("h", false, "Print command line usage")
+	printUsage := false
+
+	flag.Parse()
+
+	if *flagH || *flagHelp {
+		printUsage = true
+	}
+
+	args := flag.Args()
+
+	if *printVersion {
+		fmt.Printf("Version: %v", Build)
+		os.Exit(0)
+	}
+
+	if len(args) < 1 {
+		if printUsage {
+			help("", os.Stderr)
+			os.Exit(0)
+		}
+
+		help("No mode was provided", os.Stderr)
+		os.Exit(1)
+	} else if printUsage {
+		handleError(args[0], &helpError{}, os.Stderr)
+		os.Exit(0)
+	}
+
+	var err error
+
+	switch args[0] {
+	case "ca":
+		err = ca(args[1:], os.Stdout, os.Stderr)
+	case "keygen":
+		err = keygen(args[1:], os.Stdout, os.Stderr)
+	case "sign":
+		err = signCert(args[1:], os.Stdout, os.Stderr)
+	case "print":
+		err = printCert(args[1:], os.Stdout, os.Stderr)
+	case "verify":
+		err = verify(args[1:], os.Stdout, os.Stderr)
+	default:
+		err = fmt.Errorf("unknown mode: %s", args[0])
+	}
+
+	if err != nil {
+		os.Exit(handleError(args[0], err, os.Stderr))
+	}
+}
+
+func handleError(mode string, e error, out io.Writer) int {
+	code := 1
+
+	// Handle -help, -h flags properly
+	if e == flag.ErrHelp {
+		code = 0
+		e = &helpError{}
+	} else if e != nil && e.Error() != "" {
+		fmt.Fprintln(out, "Error:", e)
+	}
+
+	switch e.(type) {
+	case *helpError:
+		switch mode {
+		case "ca":
+			caHelp(out)
+		case "keygen":
+			keygenHelp(out)
+		case "sign":
+			signHelp(out)
+		case "print":
+			printHelp(out)
+		case "verify":
+			verifyHelp(out)
+		}
+	}
+
+	return code
+}
+
+func help(err string, out io.Writer) {
+	if err != "" {
+		fmt.Fprintln(out, "Error:", err)
+		fmt.Fprintln(out, "")
+	}
+
+	fmt.Fprintf(out, "Usage of %s <global flags> <mode>:\n", os.Args[0])
+	fmt.Fprintln(out, "  Global flags:")
+	fmt.Fprintln(out, "    -version: Prints the version")
+	fmt.Fprintln(out, "    -h, -help: Prints this help message")
+	fmt.Fprintln(out, "")
+	fmt.Fprintln(out, "  Modes:")
+	fmt.Fprintln(out, "    "+caSummary())
+	fmt.Fprintln(out, "    "+keygenSummary())
+	fmt.Fprintln(out, "    "+signSummary())
+	fmt.Fprintln(out, "    "+printSummary())
+	fmt.Fprintln(out, "    "+verifySummary())
+}
+
+func mustFlagString(name string, val *string) error {
+	if *val == "" {
+		return newHelpErrorf("-%s is required", name)
+	}
+	return nil
+}