Simple test that reads a use a private key in pem format, to encrypt and decrypt with rsa a message

rsa_test.go

package rsa_test

import (
	"crypto/rand"
	"crypto/rsa"
	"crypto/sha1"
	"crypto/x509"
	"encoding/pem"
	"io"
	"testing"
)

func TestDecodeKey(t *testing.T) {

	key, _ := pem.Decode([]byte(privateKey))
	if key == nil {
		t.Error("Private key not found")
		return
	}

	pkcs1Key, err := x509.ParsePKCS1PrivateKey(key.Bytes)
	if err != nil {
		t.Error(err)
		return
	}

	hash := sha1.New()
	data := []byte("hello world")
	io.WriteString(hash, string(data))

	s, err := rsa.EncryptPKCS1v15(rand.Reader, &pkcs1Key.PublicKey, data)
	if err != nil {
		t.Error(err)
	}

	// Now lets try to decrypt
	out, err := rsa.DecryptPKCS1v15(rand.Reader, pkcs1Key, s)
	if err != nil {
		t.Error(err)
	}
	if string(out) != string(data) {
		t.Error("The output is not the same:", string(out))
	}

}

const (
	publicKey = `
-----BEGIN PUBLIC KEY-----
MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEA0ueqo76MXuP6XqZBILFz
iH/9AI7C6PaN5W0dSvkr9yInyGHSz/IR1+4tqvP2qlfKVKI4CP6BFH251Ft9qMUB
uAsnlAVQ1z0exDtIFFOyQCdR7iXmjBIWMSS4buBwRQXwDK7id1OxtU23qVJv+xwE
V0IzaaSJmaGLIbvRBD+qatfUuQJBMU/04DdJIwvLtZBYdC2219m5dUBQaa4bimL+
YN9EcsDzD9h9UxQo5ReK7b3cNMzJBKJWLzFBcJuePMzAnLFktr/RufX4wpXe6XJx
oVPaHo72GorLkwnQ0HYMTY8rehT4mDi1FI969LHCFFaFHSAaRnwdXaQkJmSfcxzC
YQIDAQAB
-----END PUBLIC KEY-----
`

	privateKey = `
-----BEGIN RSA PRIVATE KEY-----
MIIEpAIBAAKCAQEA0ueqo76MXuP6XqZBILFziH/9AI7C6PaN5W0dSvkr9yInyGHS
z/IR1+4tqvP2qlfKVKI4CP6BFH251Ft9qMUBuAsnlAVQ1z0exDtIFFOyQCdR7iXm
jBIWMSS4buBwRQXwDK7id1OxtU23qVJv+xwEV0IzaaSJmaGLIbvRBD+qatfUuQJB
MU/04DdJIwvLtZBYdC2219m5dUBQaa4bimL+YN9EcsDzD9h9UxQo5ReK7b3cNMzJ
BKJWLzFBcJuePMzAnLFktr/RufX4wpXe6XJxoVPaHo72GorLkwnQ0HYMTY8rehT4
mDi1FI969LHCFFaFHSAaRnwdXaQkJmSfcxzCYQIDAQABAoIBAQCW3I4sKN5B9jOe
xq/pkeWBq4OvhW8Ys1yW0zFT8t6nHbB1XrwscQygd8gE9BPqj3e0iIEqtdphbPmj
VHqTYbC0FI6QDClifV7noTwTBjeIOlgZ0NSUN0/WgVzIOxUz2mZ2vBZUovKILPqG
TOi7J7RXMoySMdcXpP1f+PgvYNcnKsT72UcWaSXEV8/zo+Zm/qdGPVWwJonri5Mp
DVm5EQSENBiRyt028rU6ElXORNmoQpVjDVqZ1gipzXkifdjGyENw2rt4V/iKYD7V
5iqXOsvP6Cemf4gbrjunAgDG08S00kiUgvVWcdXW+dlsR2nCvH4DOEe3AYYh/aH8
DxEE7FbtAoGBAPcNO8fJ56mNw0ow4Qg38C+Zss/afhBOCfX4O/SZKv/roRn5+gRM
KRJYSVXNnsjPI1plzqR4OCyOrjAhtuvL4a0DinDzf1+fiztyNohwYsW1vYmqn3ti
EN0GhSgE7ppZjqvLQ3f3LUTxynhA0U+k9wflb4irIlViTUlCsOPkrNJDAoGBANqL
Q+vvuGSsmRLU/Cenjy+Mjj6+QENg51dz34o8JKuVKIPKU8pNnyeLa5fat0qD2MHm
OB9opeQOcw0dStodxr6DB3wi83bpjeU6BWUGITNiWEaZEBrQ0aiqNJJKrrHm8fAZ
9o4l4oHc4hI0kYVYYDuxtKuVJrzZiEapTwoOcYiLAoGBAI/EWbeIHZIj9zOjgjEA
LHvm25HtulLOtyk2jd1njQhlHNk7CW2azIPqcLLH99EwCYi/miNH+pijZ2aHGCXb
/bZrSxM0ADmrZKDxdB6uGCyp+GS2sBxjEyEsfCyvwhJ8b3Q100tqwiNO+d5FCglp
HICx2dgUjuRVUliBwOK93nx1AoGAUI8RhIEjOYkeDAESyhNMBr0LGjnLOosX+/as
qiotYkpjWuFULbibOFp+WMW41vDvD9qrSXir3fstkeIAW5KqVkO6mJnRoT3Knnra
zjiKOITCAZQeiaP8BO5o3pxE9TMqb9VCO3ffnPstIoTaN4syPg7tiGo8k1SklVeH
2S8lzq0CgYAKG2fljIYWQvGH628rp4ZcXS4hWmYohOxsnl1YrszbJ+hzR+IQOhGl
YlkUQYXhy9JixmUUKtH+NXkKX7Lyc8XYw5ETr7JBT3ifs+G7HruDjVG78EJVojbd
8uLA+DdQm5mg4vd1GTiSK65q/3EeoBlUaVor3HhLFki+i9qpT8CBsg==
-----END RSA PRIVATE KEY-----
`
)