Add test function

Author: Gusted

modules/crypto/ed25519_test.go

@@ -0,0 +1,43 @@
+package crypto
+
+import (
+	"bytes"
+	"crypto/rand"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+const (
+	testPublicKey  = "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIAOhB7/zzhC+HXDdGOdLwJln5NYwm6UNXx3chmQSVTG4\n"
+	testPrivateKey = `-----BEGIN OPENSSH PRIVATE KEY-----
+b3BlbnNzaC1rZXktdjEAAAAABG5vbmUAAAAEbm9uZQAAAAAAAAABAAAAMwAAAAtz
+c2gtZWQyNTUxOQAAACADoQe/884Qvh1w3RjnS8CZZ+TWMJulDV8d3IZkElUxuAAA
+AIggISIjICEiIwAAAAtzc2gtZWQyNTUxOQAAACADoQe/884Qvh1w3RjnS8CZZ+TW
+MJulDV8d3IZkElUxuAAAAEAAAQIDBAUGBwgJCgsMDQ4PEBESExQVFhcYGRobHB0e
+HwOhB7/zzhC+HXDdGOdLwJln5NYwm6UNXx3chmQSVTG4AAAAAAECAwQF
+-----END OPENSSH PRIVATE KEY-----
+`
+)
+
+func TestGeneratingEd25519Keypair(t *testing.T) {
+	// Temp override the rand.Reader for deterministic testing.
+	oldReader := rand.Reader
+	defer func() {
+		rand.Reader = oldReader
+	}()
+
+	// Only 32 bytes needs to be provided to generate a ed25519 keypair.
+	// And another 32 bytes are required, which is included as random value
+	// in the OpenSSH format.
+	b := make([]byte, 64)
+	for i := 0; i < 64; i++ {
+		b[i] = byte(i)
+	}
+	rand.Reader = bytes.NewReader(b)
+
+	publicKey, privateKey, err := GenerateEd25519Keypair()
+	assert.NoError(t, err)
+	assert.EqualValues(t, testPublicKey, string(publicKey))
+	assert.EqualValues(t, testPrivateKey, string(privateKey))
+}