ParsePKIXPublicKey in Go
ParsePKIXPublicKey parses a public key in PKIX, ASN.1 DER form.
package main
import (
"crypto/dsa"
"crypto/ecdsa"
"crypto/ed25519"
"crypto/rsa"
"crypto/x509"
"encoding/pem"
"fmt"
)
func main() {
const pubPEM = `
-----BEGIN PUBLIC KEY-----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-----END PUBLIC KEY-----`
block, _ := pem.Decode([]byte(pubPEM))
if block == nil {
panic("failed to parse PEM block containing the public key")
}
pub, err := x509.ParsePKIXPublicKey(block.Bytes)
if err != nil {
panic("failed to parse DER encoded public key: " + err.Error())
}
switch pub := pub.(type) {
case *rsa.PublicKey:
fmt.Println("pub is of type RSA:", pub)
case *dsa.PublicKey:
fmt.Println("pub is of type DSA:", pub)
case *ecdsa.PublicKey:
fmt.Println("pub is of type ECDSA:", pub)
case ed25519.PublicKey:
fmt.Println("pub is of type Ed25519:", pub)
default:
panic("unknown type of public key")
}
}