nebula/cmd/nebula-cert/print.go

108 lines
2.2 KiB
Go

package main
import (
"encoding/json"
"flag"
"fmt"
"io"
"os"
"strings"
"github.com/skip2/go-qrcode"
"github.com/slackhq/nebula/cert"
)
type printFlags struct {
set *flag.FlagSet
json *bool
outQRPath *string
path *string
}
func newPrintFlags() *printFlags {
pf := printFlags{set: flag.NewFlagSet("print", flag.ContinueOnError)}
pf.set.Usage = func() {}
pf.json = pf.set.Bool("json", false, "Optional: outputs certificates in json format")
pf.outQRPath = pf.set.String("out-qr", "", "Optional: output a qr code image (png) of the certificate")
pf.path = pf.set.String("path", "", "Required: path to the certificate")
return &pf
}
func printCert(args []string, out io.Writer, errOut io.Writer) error {
pf := newPrintFlags()
err := pf.set.Parse(args)
if err != nil {
return err
}
if err := mustFlagString("path", pf.path); err != nil {
return err
}
rawCert, err := os.ReadFile(*pf.path)
if err != nil {
return fmt.Errorf("unable to read cert; %s", err)
}
var c cert.Certificate
var qrBytes []byte
part := 0
for {
c, rawCert, err = cert.UnmarshalCertificateFromPEM(rawCert)
if err != nil {
return fmt.Errorf("error while unmarshaling cert: %s", err)
}
if *pf.json {
b, _ := json.Marshal(c)
out.Write(b)
out.Write([]byte("\n"))
} else {
out.Write([]byte(c.String()))
out.Write([]byte("\n"))
}
if *pf.outQRPath != "" {
b, err := c.MarshalPEM()
if err != nil {
return fmt.Errorf("error while marshalling cert to PEM: %s", err)
}
qrBytes = append(qrBytes, b...)
}
if rawCert == nil || len(rawCert) == 0 || strings.TrimSpace(string(rawCert)) == "" {
break
}
part++
}
if *pf.outQRPath != "" {
b, err := qrcode.Encode(string(qrBytes), qrcode.Medium, -5)
if err != nil {
return fmt.Errorf("error while generating qr code: %s", err)
}
err = os.WriteFile(*pf.outQRPath, b, 0600)
if err != nil {
return fmt.Errorf("error while writing out-qr: %s", err)
}
}
return nil
}
func printSummary() string {
return "print <flags>: prints details about a certificate"
}
func printHelp(out io.Writer) {
pf := newPrintFlags()
out.Write([]byte("Usage of " + os.Args[0] + " " + printSummary() + "\n"))
pf.set.SetOutput(out)
pf.set.PrintDefaults()
}