Golang crypto/x509.ParsePKIXPublicKey function example

package crypto/x509

ParsePKIXPublicKey parses a DER encoded public key. These values are typically found in PEM blocks with "BEGIN PUBLIC KEY".

Golang crypto/x509.ParsePKIXPublicKey function usage example

 package main

 import (
 "crypto/x509"
 "crypto/rsa"
 "os"
 "fmt"
 "encoding/pem"
 )

 func main() {

 var pemBytes = `-----BEGIN RSA PUBLIC KEY-----
 MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAufyd1F3Xqe0htJGR49cV
 aqvbGwYcmWsfKZUjB4Ijrk3wreidW3xdM0gEF828An5/sWiOT0BjgGyPL3I/GP/F
 bFRkzTFWgaejmnnSz7OVvm5sCoep8n0W9ZTtudjSdHGjUhW5hagFAjyC2C6unbe0
 ZELR0v1L1JB8ygvLiMpY97MeZCJ455gI78nvjQDZbmCJUhY+hQABC9XM8mHVSSY6
 kZ0ZkkQ47m17H40EV/wtClyr84uQIZekBlnbC4jJVSI9AMRG5J6Pd2Uj+I7VOqco
 ryBtCUfIrwjns/YdyvQDfmpR2iFUahuQDFgQzJznlutsXAo/l6kNYPj1zcnhH1zM
 vwIDAQAB
 -----END RSA PUBLIC KEY-----`


 block, _ := pem.Decode([]byte(pemBytes))

 publickey, err := x509.ParsePKIXPublicKey(block.Bytes)

 if err != nil {
 fmt.Println(err)
 os.Exit(1)
 }

 // convert publickey interface to rsa.PublicKey type
 rsaPubKey := publickey.(*rsa.PublicKey)

 fmt.Printf("Public Key N value(modulus) :  : %d\n\n", rsaPubKey.N)

 fmt.Printf("Public Key E value(exponent) :  : %d\n\n", rsaPubKey.E)

 }

Output :

Public Key N value(modulus) : : 2347865626835....4959

Public Key E value(exponent) : : 65537

Reference :

http://golang.org/pkg/crypto/x509/#ParsePKIXPublicKey