snapshot of https://github.com/grpc/grpc-go.git (master, 2026-09-15; blobs > 131072B omitted)

credentials/alts/internal/conn/aes128gcmrekey_test.go

@@ -0,0 +1,112 @@
+/*
+ *
+ * Copyright 2018 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package conn
+
+import (
+	"testing"
+
+	core "google.golang.org/grpc/credentials/alts/internal"
+)
+
+// getGCMCryptoPair outputs a client/server pair on aes128gcmRekey.
+func getRekeyCryptoPair(key []byte, counter []byte, t *testing.T) (ALTSRecordCrypto, ALTSRecordCrypto) {
+	client, err := NewAES128GCMRekey(core.ClientSide, key)
+	if err != nil {
+		t.Fatalf("NewAES128GCMRekey(ClientSide, key) = %v", err)
+	}
+	server, err := NewAES128GCMRekey(core.ServerSide, key)
+	if err != nil {
+		t.Fatalf("NewAES128GCMRekey(ServerSide, key) = %v", err)
+	}
+	// set counter if provided.
+	if counter != nil {
+		if CounterSide(counter) == core.ClientSide {
+			client.(*aes128gcmRekey).outCounter = CounterFromValue(counter, overflowLenAES128GCMRekey)
+			server.(*aes128gcmRekey).inCounter = CounterFromValue(counter, overflowLenAES128GCMRekey)
+		} else {
+			server.(*aes128gcmRekey).outCounter = CounterFromValue(counter, overflowLenAES128GCMRekey)
+			client.(*aes128gcmRekey).inCounter = CounterFromValue(counter, overflowLenAES128GCMRekey)
+		}
+	}
+	return client, server
+}
+
+func testRekeyEncryptRoundtrip(client ALTSRecordCrypto, server ALTSRecordCrypto, t *testing.T) {
+	// Encrypt.
+	const plaintext = "This is plaintext."
+	var err error
+	buf := []byte(plaintext)
+	buf, err = client.Encrypt(buf[:0], buf)
+	if err != nil {
+		t.Fatal("Encrypting with client-side context: unexpected error", err, "\n",
+			"Plaintext:", []byte(plaintext))
+	}
+
+	// Encrypt a second message.
+	const plaintext2 = "This is a second plaintext."
+	buf2 := []byte(plaintext2)
+	buf2, err = client.Encrypt(buf2[:0], buf2)
+	if err != nil {
+		t.Fatal("Encrypting with client-side context: unexpected error", err, "\n",
+			"Plaintext:", []byte(plaintext2))
+	}
+
+	// Decryption fails: cannot decrypt second message before first.
+	if got, err := server.Decrypt(nil, buf2); err == nil {
+		t.Error("Decrypting client-side ciphertext with a client-side context unexpectedly succeeded; want unexpected counter error:\n",
+			"  Original plaintext:", []byte(plaintext2), "\n",
+			"  Ciphertext:", buf2, "\n",
+			"  Decrypted plaintext:", got)
+	}
+
+	// Decryption fails: wrong counter space.
+	if got, err := client.Decrypt(nil, buf); err == nil {
+		t.Error("Decrypting client-side ciphertext with a client-side context unexpectedly succeeded; want counter space error:\n",
+			"  Original plaintext:", []byte(plaintext), "\n",
+			"  Ciphertext:", buf, "\n",
+			"  Decrypted plaintext:", got)
+	}
+
+	// Decrypt first message.
+	ciphertext := append([]byte(nil), buf...)
+	buf, err = server.Decrypt(buf[:0], buf)
+	if err != nil || string(buf) != plaintext {
+		t.Fatal("Decrypting client-side ciphertext with a server-side context did not produce original content:\n",
+			"  Original plaintext:", []byte(plaintext), "\n",
+			"  Ciphertext:", ciphertext, "\n",
+			"  Decryption error:", err, "\n",
+			"  Decrypted plaintext:", buf)
+	}
+
+	// Decryption fails: replay attack.
+	if got, err := server.Decrypt(nil, buf); err == nil {
+		t.Error("Decrypting client-side ciphertext with a client-side context unexpectedly succeeded; want unexpected counter error:\n",
+			"  Original plaintext:", []byte(plaintext), "\n",
+			"  Ciphertext:", buf, "\n",
+			"  Decrypted plaintext:", got)
+	}
+}
+
+// Test encrypt and decrypt on roundtrip messages for aes128gcmRekey.
+func (s) TestAES128GCMRekeyEncryptRoundtrip(t *testing.T) {
+	// Test for aes128gcmRekey.
+	key := make([]byte, 44)
+	client, server := getRekeyCryptoPair(key, nil, t)
+	testRekeyEncryptRoundtrip(client, server, t)
+}