Add unit tests for configuration, cryptography, interfaces, and packet handling.

pkg/cryptography/ed25519_test.go

@@ -0,0 +1,79 @@
+package cryptography
+
+import (
+	"crypto/ed25519"
+	"testing"
+)
+
+func TestGenerateSigningKeyPair(t *testing.T) {
+	pub1, priv1, err := GenerateSigningKeyPair()
+	if err != nil {
+		t.Fatalf("GenerateSigningKeyPair failed: %v", err)
+	}
+
+	if len(pub1) != ed25519.PublicKeySize {
+		t.Errorf("Public key length is %d, want %d", len(pub1), ed25519.PublicKeySize)
+	}
+	if len(priv1) != ed25519.PrivateKeySize {
+		t.Errorf("Private key length is %d, want %d", len(priv1), ed25519.PrivateKeySize)
+	}
+
+	// Generate another pair, should be different
+	pub2, priv2, err := GenerateSigningKeyPair()
+	if err != nil {
+		t.Fatalf("Second GenerateSigningKeyPair failed: %v", err)
+	}
+	if pub1.Equal(pub2) {
+		t.Error("Generated public keys are identical")
+	}
+	if priv1.Equal(priv2) {
+		t.Error("Generated private keys are identical")
+	}
+}
+
+func TestSignAndVerify(t *testing.T) {
+	pub, priv, err := GenerateSigningKeyPair()
+	if err != nil {
+		t.Fatalf("GenerateSigningKeyPair failed: %v", err)
+	}
+
+	message := []byte("This message needs to be signed.")
+
+	signature := Sign(priv, message)
+	if len(signature) != ed25519.SignatureSize {
+		t.Errorf("Signature length is %d, want %d", len(signature), ed25519.SignatureSize)
+	}
+
+	// Verify correct signature
+	if !Verify(pub, message, signature) {
+		t.Errorf("Verify failed for a valid signature")
+	}
+
+	// Verify with tampered message
+	tamperedMessage := append(message, '!')
+	if Verify(pub, tamperedMessage, signature) {
+		t.Errorf("Verify succeeded for a tampered message")
+	}
+
+	// Verify with tampered signature
+	tamperedSignature := append(signature[:len(signature)-1], ^signature[len(signature)-1])
+	if Verify(pub, message, tamperedSignature) {
+		t.Errorf("Verify succeeded for a tampered signature")
+	}
+
+	// Verify with wrong public key
+	wrongPub, _, _ := GenerateSigningKeyPair()
+	if Verify(wrongPub, message, signature) {
+		t.Errorf("Verify succeeded with the wrong public key")
+	}
+
+	// Verify empty message
+	emptyMessage := []byte("")
+	emptySig := Sign(priv, emptyMessage)
+	if !Verify(pub, emptyMessage, emptySig) {
+		t.Errorf("Verify failed for an empty message")
+	}
+	if Verify(pub, message, emptySig) {
+		t.Errorf("Verify succeeded comparing non-empty message with empty signature")
+	}
+}