1 // Copyright 2024 The Chromium Authors
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #include "crypto/aes_ctr.h"
6
7 #include "testing/gtest/include/gtest/gtest.h"
8
TEST(AesCtrTests,KnownAnswers)9 TEST(AesCtrTests, KnownAnswers) {
10 // To reproduce this test case, because openssl doesn't have a builtin
11 // aes-128-ctr mode:
12 // echo [counter hex] | xxd -r -p | openssl aes-128-ecb -K [key hex]
13 // That emits a block of key stream, which you can xor with plaintext to
14 // produce a sample ciphertext.
15 // clang-format off
16 constexpr auto kKey = std::to_array<uint8_t>({
17 0xff, 0x00, 0xee, 0x11, 0xdd, 0x22, 0xcc, 0x33,
18 0xbb, 0x44, 0xaa, 0x55, 0x99, 0x66, 0x88, 0x77,
19 });
20 constexpr auto kCounter = std::to_array<uint8_t>({
21 0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef,
22 0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef,
23 });
24 constexpr auto kPlaintext = std::to_array<uint8_t>({
25 0x0a, 0x0b, 0x0c, 0x0d, 0x0e,
26 });
27 constexpr auto kExpectedCiphertext = std::to_array<uint8_t>({
28 0xd7, 0x07, 0x48, 0x4f, 0x58,
29 });
30 // clang-format on
31 std::array<uint8_t, std::size(kPlaintext)> ciphertext;
32 std::array<uint8_t, std::size(kPlaintext)> plaintext;
33
34 crypto::aes_ctr::Encrypt(kKey, kCounter, kPlaintext, ciphertext);
35 crypto::aes_ctr::Decrypt(kKey, kCounter, ciphertext, plaintext);
36
37 EXPECT_EQ(kPlaintext, plaintext);
38 EXPECT_EQ(kExpectedCiphertext, ciphertext);
39 }
40