Separate out the scheme from the GCMMessageCryptographer

components/gcm_driver/crypto/gcm_message_cryptographer_unittest.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "components/gcm_driver/crypto/gcm_message_cryptographer.h"
 
-#include <stddef.h>
-
 #include <memory>
 
 #include "base/base64url.h"
-#include "base/macros.h"
+#include "base/memory/ptr_util.h"
 #include "base/strings/string_util.h"
 #include "components/gcm_driver/crypto/p256_key_util.h"
 #include "crypto/random.h"
 #include "crypto/symmetric_key.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace gcm {
 
 namespace {
 
+// Example plaintext data to use in the tests.
+const char kExamplePlaintext[] = "Example plaintext";
+
 // The number of bits of the key in AEAD_AES_128_GCM.
 const size_t kKeySizeBits = 128;
 
-// Example plaintext data to use in the tests.
-const char kExamplePlaintext[] = "Example plaintext";
-
-// Fixed local and peer public keys must be used to get consistent results.
-const char kLocalPublicKeyCommon[] =
+// Public keys of both the sender and the recipient as base64url-encoded
+// uncompressed P-256 EC points, as well as an authentication secret used for
+// the reference vectors. All used to create stable output.
+const char kCommonRecipientPublicKey[] =
     "BIXzEKOFquzVlr_1tS1bhmobZU3IJq2bswDflMJsizixqd_HFSvCJaCAotNjBw6A-iKQk7FshA"
     "jdAA-T9Rh1a7U";
-
-const char kPeerPublicKeyCommon[] =
+const char kCommonSenderPublicKey[] =
     "BAuzSrdIyKZsHnuOhqklkIKi6fl65V9OdPy6nFwI2SywL5-6I5SkkDtfIL9y7NkoEE345jv2Eo"
     "5n4NIbLJIBjTM";
+const char kCommonAuthSecret[] = "MyAuthenticationSecret";
 
-const char kAuthSecretCommon[] = "MyAuthenticationSecret";
-
-// A test vector contains the information necessary to either encrypt or decrypt
-// a message. These vectors were created using a JavaScript implementation of
-// the same RFCs that the GCMMessageCryptographer implements.
+// Test vectors containing reference input for draft-ietf-webpush-encryption-03
+// that was created using an separate JavaScript implementation of the draft.
 struct TestVector {
   const char* const input;
-  const char* const key;
+  const char* const ecdh_shared_secret;
   const char* const salt;
   size_t record_size;
   const char* const output;
 };
 
-const TestVector kEncryptionTestVectors[] = {
-  // Simple message.
-  { "Hello, world!",
-    "AhA6n2oFYPWIh-cXwyv1m2C0JvmjHB4ZkXj8QylESXU",
-    "tsJYqAGvFDk6lDEv7daecw",
-    4096,
-    "FgWrrnZq79oI_N4ORkVLHx1jfVmjeiIk-xFX8PzVuA"
-   },
-   // Empty message.
-   { "",
-    "lMyvTong4VR053jfCpWmMDGW5dEDAqiTZUIU-inhTjU",
-    "wH3uvZqcN6oey9whiGpn1A",
-    4096,
-    "MTI9zZ8CJTUzbZ4qNDoQZs0k"
-   },
-   // Message with an invalid salt size.
-   { "Hello, world!",
-    "CcdxzkR6z1EY9vSrM7_IxYVxDxu46hV638EZQTPd7XI",
-    "aRr1fI1YSGVi5XU",
-    4096,
-    nullptr  // expected to fail
-   }
-};
+const TestVector kEncryptionTestVectorsDraft03[] = {
+    // Simple message.
+    {"Hello, world!", "AhA6n2oFYPWIh-cXwyv1m2C0JvmjHB4ZkXj8QylESXU",
+     "tsJYqAGvFDk6lDEv7daecw", 4096,
+     "FgWrrnZq79oI_N4ORkVLHx1jfVmjeiIk-xFX8PzVuA"},
+    // Empty message.
+    {"", "lMyvTong4VR053jfCpWmMDGW5dEDAqiTZUIU-inhTjU",
+     "wH3uvZqcN6oey9whiGpn1A", 4096, "MTI9zZ8CJTUzbZ4qNDoQZs0k"},
+    // Message with an invalid salt size.
+    {
+        "Hello, world!", "CcdxzkR6z1EY9vSrM7_IxYVxDxu46hV638EZQTPd7XI",
+        "aRr1fI1YSGVi5XU", 4096,
+        nullptr  // expected to fail
+    }};
 
-const TestVector kDecryptionTestVectors[] = {
-  // Simple message.
-  { "ceiEu_YpmqLoakD4smdzvy2XKRQrJ9vBzB2aqYEfzw",
-    "47ZytAw9qHlm-Q8g-7rH81rUPzaCgGcoFvlS1qxQtQk",
-    "EuR7EVetcaWpndXd_dKeyA",
-    4096,
-    "Hello, world!"
-   },
-   // Simple message with 16 bytes of padding.
-   { "WSf6fz1O0aIJyaPTCnvk83OqIQxsRKeFOvblPLsPpFB_1AV9ROk09TE1cGrB6zQ",
-     "MYSsNybwrTzRIzQYUq_yFPc6ugcTrJdEZJDM4NswvUg",
-     "8sEAMQYnufo2UkKl80cUGQ",
-     4096,
-     "Hello, world!"
-   },
-   // Empty message.
-   { "Ur3vHedGDO5IPYDvbhHYjbjG",
-     "S3-Ki_-XtzR66gUp_zR75CC5JXO62pyr5fWfneTYwFE",
-     "4RM6s19jJHdmqiVEJDp9jg",
-     4096,
-     ""
-   },
-   // Message with an invalid salt size.
-   { "iGrOpmJC5XTTf7wtgdhZ_qT",
-     "wW3Iy5ma803lLd-ysPdHUe2NB3HqXbY0XhCCdG5Y1Gw",
-     "N7oMH_xohAhMhOY",
-     4096,
-     nullptr  // expected to fail
-   },
-   // Message with an invalid record size.
-   { "iGrOpmJC5XTTf7wtgdhZ_qT",
-     "kR5BMfqMKOD1yrLKE2giObXHI7merrMtnoO2oqneqXA",
-     "SQeJSPrqHvTdSfAMF8bBzQ",
-     8,
-     nullptr  // expected to fail
-   },
-   // Message with multiple (2) records.
-   { "RqQVHRXlfYjzW9xhzh3V_KijLKjZiKzGXosqN_IaMzi0zI0tXXhC1urtrk3iWRoqttNXpkD2r"
-         "UCgLy8A1FnTjw",
-     "W3W4gx7sqcfmBnvNNdO9d4MBCC1bvJkvsNjZOGD-CCg",
-     "xG0TPGi9aIcxjpXKmaYBBQ",
-     7,
-     nullptr  // expected to fail
-   }
-};
+const TestVector kDecryptionTestVectorsDraft03[] = {
+    // Simple message.
+    {"ceiEu_YpmqLoakD4smdzvy2XKRQrJ9vBzB2aqYEfzw",
+     "47ZytAw9qHlm-Q8g-7rH81rUPzaCgGcoFvlS1qxQtQk", "EuR7EVetcaWpndXd_dKeyA",
+     4096, "Hello, world!"},
+    // Simple message with 16 bytes of padding.
+    {"WSf6fz1O0aIJyaPTCnvk83OqIQxsRKeFOvblPLsPpFB_1AV9ROk09TE1cGrB6zQ",
+     "MYSsNybwrTzRIzQYUq_yFPc6ugcTrJdEZJDM4NswvUg", "8sEAMQYnufo2UkKl80cUGQ",
+     4096, "Hello, world!"},
+    // Empty message.
+    {"Ur3vHedGDO5IPYDvbhHYjbjG", "S3-Ki_-XtzR66gUp_zR75CC5JXO62pyr5fWfneTYwFE",
+     "4RM6s19jJHdmqiVEJDp9jg", 4096, ""},
+    // Message with an invalid salt size.
+    {
+        "iGrOpmJC5XTTf7wtgdhZ_qT",
+        "wW3Iy5ma803lLd-ysPdHUe2NB3HqXbY0XhCCdG5Y1Gw", "N7oMH_xohAhMhOY", 4096,
+        nullptr  // expected to fail
+    },
+    // Message with an invalid record size.
+    {
+        "iGrOpmJC5XTTf7wtgdhZ_qT",
+        "kR5BMfqMKOD1yrLKE2giObXHI7merrMtnoO2oqneqXA", "SQeJSPrqHvTdSfAMF8bBzQ",
+        8,
+        nullptr  // expected to fail
+    },
+    // Message with multiple (2) records.
+    {
+        "RqQVHRXlfYjzW9xhzh3V_KijLKjZiKzGXosqN_"
+        "IaMzi0zI0tXXhC1urtrk3iWRoqttNXpkD2r"
+        "UCgLy8A1FnTjw",
+        "W3W4gx7sqcfmBnvNNdO9d4MBCC1bvJkvsNjZOGD-CCg", "xG0TPGi9aIcxjpXKmaYBBQ",
+        7,
+        nullptr  // expected to fail
+    }};
 
 }  // namespace
 
 class GCMMessageCryptographerTest : public ::testing::Test {
  public:
   void SetUp() override {
+    cryptographer_ = base::MakeUnique<GCMMessageCryptographer>(
+        GCMMessageCryptographer::Version::DRAFT_03);
+
+    ASSERT_TRUE(base::Base64UrlDecode(
+        kCommonRecipientPublicKey, base::Base64UrlDecodePolicy::IGNORE_PADDING,
+        &recipient_public_key_));
+    ASSERT_TRUE(base::Base64UrlDecode(
+        kCommonSenderPublicKey, base::Base64UrlDecodePolicy::IGNORE_PADDING,
+        &sender_public_key_));
+
     std::unique_ptr<crypto::SymmetricKey> random_key(
         crypto::SymmetricKey::GenerateRandomKey(crypto::SymmetricKey::AES,
                                                 kKeySizeBits));
 
-    ASSERT_TRUE(random_key->GetRawKey(&key_));
-
-    std::string local_public_key, peer_public_key;
-    ASSERT_TRUE(base::Base64UrlDecode(
-        kLocalPublicKeyCommon, base::Base64UrlDecodePolicy::IGNORE_PADDING,
-        &local_public_key));
-    ASSERT_TRUE(base::Base64UrlDecode(
-        kPeerPublicKeyCommon, base::Base64UrlDecodePolicy::IGNORE_PADDING,
-        &peer_public_key));
-
-    cryptographer_.reset(
-        new GCMMessageCryptographer(local_public_key, peer_public_key,
-                                    kAuthSecretCommon));
+    ASSERT_TRUE(random_key->GetRawKey(&ecdh_shared_secret_));
   }
 
  protected:
   // Generates a cryptographically secure random salt of 16-octets in size, the
   // required length as expected by the HKDF.
   std::string GenerateRandomSalt() {
     const size_t kSaltSize = 16;
 
     std::string salt;
 
     crypto::RandBytes(base::WriteInto(&salt, kSaltSize + 1), kSaltSize);
     return salt;
   }
 
-  GCMMessageCryptographer* cryptographer() { return cryptographer_.get(); }
+  // Public keys of the recipient and sender as uncompressed P-256 EC points.
+  std::string recipient_public_key_;
+  std::string sender_public_key_;
 
-  base::StringPiece key() const { return key_; }
+  // Shared secret to use in transformations. Unrelated to the keys above.
+  std::string ecdh_shared_secret_;
 
- private:
+  // The GCMMessageCryptographer instance to use for the tests.
   std::unique_ptr<GCMMessageCryptographer> cryptographer_;
-
-  std::string key_;
 };
 
 TEST_F(GCMMessageCryptographerTest, RoundTrip) {
   const std::string salt = GenerateRandomSalt();
 
   size_t record_size = 0;
 
   std::string ciphertext, plaintext;
-  ASSERT_TRUE(cryptographer()->Encrypt(kExamplePlaintext, key(), salt,
-                                       &record_size, &ciphertext));
+  ASSERT_TRUE(cryptographer_->Encrypt(
+      recipient_public_key_, sender_public_key_, ecdh_shared_secret_,
+      kCommonAuthSecret, salt, kExamplePlaintext, &record_size, &ciphertext));
 
   EXPECT_GT(record_size, ciphertext.size() - 16);
   EXPECT_GT(ciphertext.size(), 0u);
 
-  ASSERT_TRUE(cryptographer()->Decrypt(ciphertext, key(), salt, record_size,
-                                       &plaintext));
+  ASSERT_TRUE(cryptographer_->Decrypt(
+      recipient_public_key_, sender_public_key_, ecdh_shared_secret_,
+      kCommonAuthSecret, salt, ciphertext, record_size, &plaintext));
 
   EXPECT_EQ(kExamplePlaintext, plaintext);
 }
 
 TEST_F(GCMMessageCryptographerTest, RoundTripEmptyMessage) {
   const std::string salt = GenerateRandomSalt();
   const std::string message = "";
 
   size_t record_size = 0;
 
   std::string ciphertext, plaintext;
-  ASSERT_TRUE(cryptographer()->Encrypt(message, key(), salt, &record_size,
-                                       &ciphertext));
+  ASSERT_TRUE(cryptographer_->Encrypt(
+      recipient_public_key_, sender_public_key_, ecdh_shared_secret_,
+      kCommonAuthSecret, salt, message, &record_size, &ciphertext));
 
   EXPECT_GT(record_size, ciphertext.size() - 16);
   EXPECT_GT(ciphertext.size(), 0u);
 
-  ASSERT_TRUE(cryptographer()->Decrypt(ciphertext, key(), salt, record_size,
-                                       &plaintext));
+  ASSERT_TRUE(cryptographer_->Decrypt(
+      recipient_public_key_, sender_public_key_, ecdh_shared_secret_,
+      kCommonAuthSecret, salt, ciphertext, record_size, &plaintext));
 
   EXPECT_EQ(message, plaintext);
 }
 
 TEST_F(GCMMessageCryptographerTest, InvalidRecordSize) {
   const std::string salt = GenerateRandomSalt();
 
   size_t record_size = 0;
 
   std::string ciphertext, plaintext;
-  ASSERT_TRUE(cryptographer()->Encrypt(kExamplePlaintext, key(), salt,
-                                       &record_size, &ciphertext));
+  ASSERT_TRUE(cryptographer_->Encrypt(
+      recipient_public_key_, sender_public_key_, ecdh_shared_secret_,
+      kCommonAuthSecret, salt, kExamplePlaintext, &record_size, &ciphertext));
 
   EXPECT_GT(record_size, ciphertext.size() - 16);
-  EXPECT_FALSE(cryptographer()->Decrypt(ciphertext, key(), salt,
-                                        0 /* record_size */, &plaintext));
 
-  EXPECT_FALSE(cryptographer()->Decrypt(ciphertext, key(), salt,
-                                        ciphertext.size() - 17, &plaintext));
+  EXPECT_FALSE(cryptographer_->Decrypt(
+      recipient_public_key_, sender_public_key_, ecdh_shared_secret_,
+      kCommonAuthSecret, salt, ciphertext, 0 /* record_size */, &plaintext));
 
-  EXPECT_TRUE(cryptographer()->Decrypt(ciphertext, key(), salt,
-                                       ciphertext.size() - 16, &plaintext));
+  EXPECT_FALSE(cryptographer_->Decrypt(
+      recipient_public_key_, sender_public_key_, ecdh_shared_secret_,
+      kCommonAuthSecret, salt, ciphertext, ciphertext.size() - 17, &plaintext));
+
+  EXPECT_TRUE(cryptographer_->Decrypt(
+      recipient_public_key_, sender_public_key_, ecdh_shared_secret_,
+      kCommonAuthSecret, salt, ciphertext, ciphertext.size() - 16, &plaintext));
 }
 
 TEST_F(GCMMessageCryptographerTest, InvalidRecordPadding) {
   std::string message = std::string(sizeof(uint16_t), '\0') + kExamplePlaintext;
 
   const std::string salt = GenerateRandomSalt();
 
-  const std::string prk = cryptographer()->DerivePseudoRandomKey(key());
-  const std::string nonce = cryptographer()->DeriveNonce(prk, salt);
+  const std::string prk =
+      cryptographer_->encryption_scheme_->DerivePseudoRandomKey(
+          ecdh_shared_secret_, kCommonAuthSecret);
   const std::string content_encryption_key =
-      cryptographer()->DeriveContentEncryptionKey(prk, salt);
+      cryptographer_->DeriveContentEncryptionKey(recipient_public_key_,
+                                                 sender_public_key_, prk, salt);
+  const std::string nonce = cryptographer_->DeriveNonce(
+      recipient_public_key_, sender_public_key_, prk, salt);
 
   ASSERT_GT(message.size(), 1u);
   const size_t record_size = message.size() + 1;
 
   std::string ciphertext, plaintext;
-  ASSERT_TRUE(cryptographer()->EncryptDecryptRecordInternal(
-      GCMMessageCryptographer::ENCRYPT, message, content_encryption_key, nonce,
-      &ciphertext));
+  ASSERT_TRUE(cryptographer_->TransformRecord(
+      GCMMessageCryptographer::Direction::ENCRYPT, message,
+      content_encryption_key, nonce, &ciphertext));
 
-  ASSERT_TRUE(cryptographer()->Decrypt(ciphertext, key(), salt, record_size,
-                                       &plaintext));
+  ASSERT_TRUE(cryptographer_->Decrypt(
+      recipient_public_key_, sender_public_key_, ecdh_shared_secret_,
+      kCommonAuthSecret, salt, ciphertext, record_size, &plaintext));
 
   // Note that GCMMessageCryptographer::Decrypt removes the padding.
   EXPECT_EQ(kExamplePlaintext, plaintext);
 
   // Now run the same steps again, but say that there are four padding octets.
   // This should be rejected because the padding will not be all zeros.
   message[0] = 4;
 
-  ASSERT_TRUE(cryptographer()->EncryptDecryptRecordInternal(
-      GCMMessageCryptographer::ENCRYPT, message, content_encryption_key, nonce,
-      &ciphertext));
+  ASSERT_TRUE(cryptographer_->TransformRecord(
+      GCMMessageCryptographer::Direction::ENCRYPT, message,
+      content_encryption_key, nonce, &ciphertext));
 
-  ASSERT_FALSE(cryptographer()->Decrypt(ciphertext, key(), salt, record_size,
-                                        &plaintext));
+  ASSERT_FALSE(cryptographer_->Decrypt(
+      recipient_public_key_, sender_public_key_, ecdh_shared_secret_,
+      kCommonAuthSecret, salt, ciphertext, record_size, &plaintext));
 
   // Do the same but changing the second octet indicating padding size, leaving
   // the first octet at zero.
   message[0] = 0;
   message[1] = 4;
 
-  ASSERT_TRUE(cryptographer()->EncryptDecryptRecordInternal(
-      GCMMessageCryptographer::ENCRYPT, message, content_encryption_key, nonce,
-      &ciphertext));
+  ASSERT_TRUE(cryptographer_->TransformRecord(
+      GCMMessageCryptographer::Direction::ENCRYPT, message,
+      content_encryption_key, nonce, &ciphertext));
 
-  ASSERT_FALSE(cryptographer()->Decrypt(ciphertext, key(), salt, record_size,
-                                        &plaintext));
+  ASSERT_FALSE(cryptographer_->Decrypt(
+      recipient_public_key_, sender_public_key_, ecdh_shared_secret_,
+      kCommonAuthSecret, salt, ciphertext, record_size, &plaintext));
 
   // Run the same steps again, but say that there are more padding octets than
   // the length of the message.
   message[0] = 64;
 
   EXPECT_GT(static_cast<size_t>(message[0]), message.size());
-  ASSERT_TRUE(cryptographer()->EncryptDecryptRecordInternal(
-      GCMMessageCryptographer::ENCRYPT, message, content_encryption_key, nonce,
-      &ciphertext));
+  ASSERT_TRUE(cryptographer_->TransformRecord(
+      GCMMessageCryptographer::Direction::ENCRYPT, message,
+      content_encryption_key, nonce, &ciphertext));
 
-  ASSERT_FALSE(cryptographer()->Decrypt(ciphertext, key(), salt, record_size,
-                                        &plaintext));
+  ASSERT_FALSE(cryptographer_->Decrypt(
+      recipient_public_key_, sender_public_key_, ecdh_shared_secret_,
+      kCommonAuthSecret, salt, ciphertext, record_size, &plaintext));
 }
 
-TEST_F(GCMMessageCryptographerTest, EncryptionTestVectors) {
-  std::string key, salt, output, ciphertext;
+TEST_F(GCMMessageCryptographerTest, AuthSecretAffectsPRK) {
+  ASSERT_NE(cryptographer_->encryption_scheme_->DerivePseudoRandomKey(
+                ecdh_shared_secret_, "Hello"),
+            cryptographer_->encryption_scheme_->DerivePseudoRandomKey(
+                ecdh_shared_secret_, "World"));
+
+  std::string salt = GenerateRandomSalt();
+
+  // Verify that the IKM actually gets used by the transformations.
+  size_t hello_record_size, world_record_size;
+  std::string hello_ciphertext, world_ciphertext;
+
+  ASSERT_TRUE(cryptographer_->Encrypt(
+      recipient_public_key_, sender_public_key_, ecdh_shared_secret_, "Hello",
+      salt, kExamplePlaintext, &hello_record_size, &hello_ciphertext));
+
+  ASSERT_TRUE(cryptographer_->Encrypt(
+      recipient_public_key_, sender_public_key_, ecdh_shared_secret_, "World",
+      salt, kExamplePlaintext, &world_record_size, &world_ciphertext));
+
+  // If the ciphertexts differ despite the same key and salt, it got used.
+  ASSERT_NE(hello_ciphertext, world_ciphertext);
+  EXPECT_EQ(hello_record_size, world_record_size);
+
+  // Verify that the different ciphertexts can also be translated back to the
+  // plaintext content. This will fail if the auth secret isn't considered.
+  std::string hello_plaintext, world_plaintext;
+
+  ASSERT_TRUE(cryptographer_->Decrypt(
+      recipient_public_key_, sender_public_key_, ecdh_shared_secret_, "Hello",
+      salt, hello_ciphertext, hello_record_size, &hello_plaintext));
+
+  ASSERT_TRUE(cryptographer_->Decrypt(
+      recipient_public_key_, sender_public_key_, ecdh_shared_secret_, "World",
+      salt, world_ciphertext, world_record_size, &world_plaintext));
+
+  EXPECT_EQ(kExamplePlaintext, hello_plaintext);
+  EXPECT_EQ(kExamplePlaintext, world_plaintext);
+}
+
+class GCMMessageCryptographerTestVectorTest
+    : public GCMMessageCryptographerTest {};
+
+TEST_F(GCMMessageCryptographerTestVectorTest, EncryptionVectorsDraft03) {
+  std::string ecdh_shared_secret, salt, output, ciphertext;
   size_t record_size = 0;
 
-  for (size_t i = 0; i < arraysize(kEncryptionTestVectors); ++i) {
+  for (size_t i = 0; i < arraysize(kEncryptionTestVectorsDraft03); ++i) {
     SCOPED_TRACE(i);
 
     ASSERT_TRUE(base::Base64UrlDecode(
-        kEncryptionTestVectors[i].key,
-        base::Base64UrlDecodePolicy::IGNORE_PADDING, &key));
+        kEncryptionTestVectorsDraft03[i].ecdh_shared_secret,
+        base::Base64UrlDecodePolicy::IGNORE_PADDING, &ecdh_shared_secret));
     ASSERT_TRUE(base::Base64UrlDecode(
-        kEncryptionTestVectors[i].salt,
+        kEncryptionTestVectorsDraft03[i].salt,
         base::Base64UrlDecodePolicy::IGNORE_PADDING, &salt));
 
-    const bool has_output = kEncryptionTestVectors[i].output;
-    const bool result = cryptographer()->Encrypt(
-        kEncryptionTestVectors[i].input, key, salt, &record_size, &ciphertext);
+    const bool has_output = kEncryptionTestVectorsDraft03[i].output;
+    const bool result = cryptographer_->Encrypt(
+        recipient_public_key_, sender_public_key_, ecdh_shared_secret,
+        kCommonAuthSecret, salt, kEncryptionTestVectorsDraft03[i].input,
+        &record_size, &ciphertext);
 
     if (!has_output) {
       EXPECT_FALSE(result);
       continue;
     }
 
     EXPECT_TRUE(result);
     ASSERT_TRUE(base::Base64UrlDecode(
-        kEncryptionTestVectors[i].output,
+        kEncryptionTestVectorsDraft03[i].output,
         base::Base64UrlDecodePolicy::IGNORE_PADDING, &output));
 
-    EXPECT_EQ(kEncryptionTestVectors[i].record_size, record_size);
+    EXPECT_EQ(kEncryptionTestVectorsDraft03[i].record_size, record_size);
     EXPECT_EQ(output, ciphertext);
   }
 }
 
-TEST_F(GCMMessageCryptographerTest, DecryptionTestVectors) {
-  std::string input, key, salt, plaintext;
-  for (size_t i = 0; i < arraysize(kDecryptionTestVectors); ++i) {
+TEST_F(GCMMessageCryptographerTestVectorTest, DecryptionVectorsDraft03) {
+  std::string input, ecdh_shared_secret, salt, plaintext;
+  for (size_t i = 0; i < arraysize(kDecryptionTestVectorsDraft03); ++i) {
     SCOPED_TRACE(i);
 
     ASSERT_TRUE(base::Base64UrlDecode(
-        kDecryptionTestVectors[i].input,
+        kDecryptionTestVectorsDraft03[i].input,
         base::Base64UrlDecodePolicy::IGNORE_PADDING, &input));
     ASSERT_TRUE(base::Base64UrlDecode(
-        kDecryptionTestVectors[i].key,
-        base::Base64UrlDecodePolicy::IGNORE_PADDING, &key));
+        kDecryptionTestVectorsDraft03[i].ecdh_shared_secret,
+        base::Base64UrlDecodePolicy::IGNORE_PADDING, &ecdh_shared_secret));
     ASSERT_TRUE(base::Base64UrlDecode(
-        kDecryptionTestVectors[i].salt,
+        kDecryptionTestVectorsDraft03[i].salt,
         base::Base64UrlDecodePolicy::IGNORE_PADDING, &salt));
 
-    const bool has_output = kDecryptionTestVectors[i].output;
-    const bool result = cryptographer()->Decrypt(
-        input, key, salt, kDecryptionTestVectors[i].record_size, &plaintext);
+    const bool has_output = kDecryptionTestVectorsDraft03[i].output;
+    const bool result = cryptographer_->Decrypt(
+        recipient_public_key_, sender_public_key_, ecdh_shared_secret,
+        kCommonAuthSecret, salt, input,
+        kDecryptionTestVectorsDraft03[i].record_size, &plaintext);
 
     if (!has_output) {
       EXPECT_FALSE(result);
       continue;
     }
 
     EXPECT_TRUE(result);
-    EXPECT_EQ(kDecryptionTestVectors[i].output, plaintext);
+    EXPECT_EQ(kDecryptionTestVectorsDraft03[i].output, plaintext);
   }
 }
 
-TEST_F(GCMMessageCryptographerTest, AuthSecretAffectsIKM) {
-  std::string public_key;
-  ASSERT_TRUE(base::Base64UrlDecode(
-      kLocalPublicKeyCommon, base::Base64UrlDecodePolicy::IGNORE_PADDING,
-      &public_key));
-
-  // Fake IKM to use in the DerivePseudoRandomKey calls.
-  const char kFakeIKM[] = "HelloWorld";
-
-  GCMMessageCryptographer hello_cryptographer(public_key, public_key, "Hello");
-
-  GCMMessageCryptographer world_cryptographer(public_key, public_key, "World");
-
-  ASSERT_NE(hello_cryptographer.DerivePseudoRandomKey(kFakeIKM), kFakeIKM);
-  ASSERT_NE(world_cryptographer.DerivePseudoRandomKey(kFakeIKM), kFakeIKM);
-
-  ASSERT_NE(hello_cryptographer.DerivePseudoRandomKey(kFakeIKM),
-            world_cryptographer.DerivePseudoRandomKey(kFakeIKM));
-
-  std::string salt = GenerateRandomSalt();
-
-  // Verify that the IKM actually gets used by the transformations.
-  size_t hello_record_size, world_record_size;
-  std::string hello_ciphertext, world_ciphertext;
-
-  ASSERT_TRUE(hello_cryptographer.Encrypt(kExamplePlaintext, key(), salt,
-                                          &hello_record_size,
-                                          &hello_ciphertext));
-  ASSERT_TRUE(world_cryptographer.Encrypt(kExamplePlaintext, key(), salt,
-                                          &world_record_size,
-                                          &world_ciphertext));
-
-  // If the ciphertexts differ despite the same key and salt, it got used.
-  ASSERT_NE(hello_ciphertext, world_ciphertext);
-
-  // Verify that the different ciphertexts can also be translated back to the
-  // plaintext content. This will fail if the auth secret isn't considered.
-  std::string hello_plaintext, world_plaintext;
-
-  ASSERT_TRUE(hello_cryptographer.Decrypt(hello_ciphertext, key(), salt,
-                                          hello_record_size, &hello_plaintext));
-  ASSERT_TRUE(world_cryptographer.Decrypt(world_ciphertext, key(), salt,
-                                          world_record_size, &world_plaintext));
-
-  EXPECT_EQ(kExamplePlaintext, hello_plaintext);
-  EXPECT_EQ(kExamplePlaintext, world_plaintext);
-}
-
-// Common infrastructure for reference tests against the examples in the draft:
-// https://tools.ietf.org/html/draft-thomson-http-encryption
-class GCMMessageCryptographerReferenceTest
-    : public GCMMessageCryptographerTest {
+class GCMMessageCryptographerReferenceTest : public ::testing::Test {
  protected:
   // Computes the shared secret between the sender and the receiver. The sender
   // must have a key-pair containing a X.509 SubjectPublicKeyInfo block and a
   // ASN.1-encoded PKCS #8 EncryptedPrivateKeyInfo block, whereas the receiver
   // must have a public key in uncompressed EC point format.
   void ComputeSharedSecret(const char* encoded_sender_private_key,
                            const char* encoded_sender_public_key_x509,
                            const char* encoded_receiver_public_key,
                            std::string* shared_secret) const {
     std::string sender_private_key, sender_public_key_x509, receiver_public_key;
     ASSERT_TRUE(base::Base64UrlDecode(
         encoded_sender_private_key,
         base::Base64UrlDecodePolicy::IGNORE_PADDING, &sender_private_key));
     ASSERT_TRUE(base::Base64UrlDecode(
         encoded_sender_public_key_x509,
         base::Base64UrlDecodePolicy::IGNORE_PADDING, &sender_public_key_x509));
     ASSERT_TRUE(base::Base64UrlDecode(
         encoded_receiver_public_key,
         base::Base64UrlDecodePolicy::IGNORE_PADDING, &receiver_public_key));
 
     ASSERT_TRUE(ComputeSharedP256Secret(
         sender_private_key, sender_public_key_x509, receiver_public_key,
         shared_secret));
   }
-
-  // Creates a new cryptographer based on the P-256 curve with the given public
-  // keys of the sender and receiver, and optionally, the authentication secret.
-  // The public keys must be given as uncompressed P-256 EC points.
-  void CreateCryptographer(
-      const char* encoded_receiver_public_key,
-      const char* encoded_sender_public_key,
-      const char* encoded_auth_secret,
-      std::unique_ptr<GCMMessageCryptographer>* cryptographer) const {
-    std::string receiver_public_key, sender_public_key, auth_secret;
-    ASSERT_TRUE(base::Base64UrlDecode(
-        encoded_receiver_public_key,
-        base::Base64UrlDecodePolicy::IGNORE_PADDING, &receiver_public_key));
-    ASSERT_TRUE(base::Base64UrlDecode(
-        encoded_sender_public_key,
-        base::Base64UrlDecodePolicy::IGNORE_PADDING, &sender_public_key));
-
-    if (encoded_auth_secret) {
-      ASSERT_TRUE(base::Base64UrlDecode(
-          encoded_auth_secret,
-          base::Base64UrlDecodePolicy::IGNORE_PADDING, &auth_secret));
-    }
-
-    std::unique_ptr<GCMMessageCryptographer> instance(
-        new GCMMessageCryptographer(receiver_public_key, sender_public_key,
-                                    auth_secret));
-
-    if (auth_secret.empty())
-      instance->set_allow_empty_auth_secret_for_tests(true);
-
-    cryptographer->swap(instance);
-  }
 };
 
-TEST_F(GCMMessageCryptographerReferenceTest, WithAuthSecret) {
+// Reference test included for the Version::DRAFT_03 implementation.
+// https://tools.ietf.org/html/draft-ietf-webpush-encryption-03
+// https://tools.ietf.org/html/draft-ietf-httpbis-encryption-encoding-02
+TEST_F(GCMMessageCryptographerReferenceTest, ReferenceDraft03) {
   // The 16-byte salt unique to the message.
   const char kSalt[] = "lngarbyKfMoi9Z75xYXmkg";
 
   // The 16-byte prearranged secret between the sender and receiver.
   const char kAuthSecret[] = "R29vIGdvbyBnJyBqb29iIQ";
 
   // The keying material used by the sender to encrypt the |kCiphertext|.
   const char kSenderPrivate[] =
       "MIGxMBwGCiqGSIb3DQEMAQMwDgQIh9aZ3UvuDloCAggABIGQZ-T8CJZe-no4mOTDgX1Gm986"
       "Gsbe3mjJeABhA4KOmut_qJh5kt_DLqdNShiQr-afk3AdkX-fxLZdrcHiW9aWvBjnMAY65zg5"
       "oHsuUaoEuG88Ksbku2u193OENWTQTsYaYE2O44qmRfsX773UNVcWXg_omwIbhbgf6tLZUZH_"
       "dTC3YjzuxjbSP89HPEJ-eBXA";
-  const char kSenderPublicUncompressed[] =
+  const char kSenderPublicKeyUncompressed[] =
       "BNoRDbb84JGm8g5Z5CFxurSqsXWJ11ItfXEWYVLE85Y7CYkDjXsIEc4aqxYaQ1G8BqkXCJ6D"
       "PpDrWtdWj_mugHU";
   const char kSenderPublicX509[] =
       "MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAE2hENtvzgkabyDlnkIXG6tKqxdYnXUi19cRZh"
       "UsTzljsJiQONewgRzhqrFhpDUbwGqRcInoM-kOta11aP-a6AdQ";
 
-  // The keying material used by the client to decrypt the |kCiphertext|.
-  const char kReceiverPrivate[] =
+  // The keying material used by the recipient to decrypt the |kCiphertext|.
+  const char kRecipientPrivate[] =
       "MIGxMBwGCiqGSIb3DQEMAQMwDgQIqMt4d7uJdt4CAggABIGQeikRHE3CqUeF-uUtJno9BL0g"
       "mNRyDihZe8P3nF_g-NYVzvdQowsXfYeza6OQOdDuMXxnGgNToVy2jsiWVN6rxCaSMTY622y8"
       "ajW5voSdqC2PakQ8ZNTPNHarLDMC9NpgGKrUh8hfRLhvb7vtbKIWmx-22rQB5yTYdqzN2m7A"
       "GHMWRnVk0mMzMsMjZqYFaa2D";
-  const char kReceiverPublicUncompressed[] =
+  const char kRecipientPublicKeyUncompressed[] =
       "BCEkBjzL8Z3C-oi2Q7oE5t2Np-p7osjGLg93qUP0wvqRT21EEWyf0cQDQcakQMqz4hQKYOQ3"
       "il2nNZct4HgAUQU";
-  const char kReceiverPublicX509[] =
+  const char kRecipientPublicX509[] =
       "MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAEISQGPMvxncL6iLZDugTm3Y2n6nuiyMYuD3ep"
       "Q_TC-pFPbUQRbJ_RxANBxqRAyrPiFApg5DeKXac1ly3geABRBQ";
 
   // The ciphertext and associated plaintext of the message.
   const char kCiphertext[] = "6nqAQUME8hNqw5J3kl8cpVVJylXKYqZOeseZG8UueKpA";
   const char kPlaintext[] = "I am the walrus";
 
   std::string sender_shared_secret, receiver_shared_secret;
 
   // Compute the shared secrets between the sender and receiver's keys.
+  ASSERT_NO_FATAL_FAILURE(ComputeSharedSecret(kSenderPrivate, kSenderPublicX509,
+                                              kRecipientPublicKeyUncompressed,
+                                              &sender_shared_secret));
   ASSERT_NO_FATAL_FAILURE(ComputeSharedSecret(
-      kSenderPrivate, kSenderPublicX509, kReceiverPublicUncompressed,
-      &sender_shared_secret));
-  ASSERT_NO_FATAL_FAILURE(ComputeSharedSecret(
-      kReceiverPrivate, kReceiverPublicX509, kSenderPublicUncompressed,
+      kRecipientPrivate, kRecipientPublicX509, kSenderPublicKeyUncompressed,
       &receiver_shared_secret));
 
   ASSERT_GT(sender_shared_secret.size(), 0u);
   ASSERT_EQ(sender_shared_secret, receiver_shared_secret);
 
-  std::unique_ptr<GCMMessageCryptographer> cryptographer;
-  ASSERT_NO_FATAL_FAILURE(CreateCryptographer(
-      kReceiverPublicUncompressed, kSenderPublicUncompressed, kAuthSecret,
-      &cryptographer));
-
-  std::string salt;
+  // Decode the public keys of both parties, the auth secret and the salt.
+  std::string recipient_public_key, sender_public_key, auth_secret, salt;
+  ASSERT_TRUE(base::Base64UrlDecode(kRecipientPublicKeyUncompressed,
+                                    base::Base64UrlDecodePolicy::IGNORE_PADDING,
+                                    &recipient_public_key));
+  ASSERT_TRUE(base::Base64UrlDecode(kSenderPublicKeyUncompressed,
+                                    base::Base64UrlDecodePolicy::IGNORE_PADDING,
+                                    &sender_public_key));
+  ASSERT_TRUE(base::Base64UrlDecode(
+      kAuthSecret, base::Base64UrlDecodePolicy::IGNORE_PADDING, &auth_secret));
   ASSERT_TRUE(base::Base64UrlDecode(
         kSalt, base::Base64UrlDecodePolicy::IGNORE_PADDING, &salt));
 
   std::string encoded_ciphertext, ciphertext, plaintext;
   size_t record_size = 0;
 
-  // Verify that encrypting |kPlaintext| yields the expected |kCiphertext|.
-  ASSERT_TRUE(cryptographer->Encrypt(kPlaintext, sender_shared_secret, salt,
-                                     &record_size, &ciphertext));
+  // Now verify that encrypting a message with the given information yields the
+  // expected ciphertext given the defined input.
+  GCMMessageCryptographer cryptographer(
+      GCMMessageCryptographer::Version::DRAFT_03);
+
+  ASSERT_TRUE(cryptographer.Encrypt(recipient_public_key, sender_public_key,
+                                    sender_shared_secret, auth_secret, salt,
+                                    kPlaintext, &record_size, &ciphertext));
 
   base::Base64UrlEncode(ciphertext, base::Base64UrlEncodePolicy::OMIT_PADDING,
                         &encoded_ciphertext);
   ASSERT_EQ(kCiphertext, encoded_ciphertext);
 
-  // Verify that decrypting |kCiphertext| yields the expected |kPlaintext|.
-  ASSERT_TRUE(cryptographer->Decrypt(ciphertext, sender_shared_secret, salt,
-                                     record_size, &plaintext));
+  // And verify that decrypting themessageyields the plaintext again.

[martijnc, 2017/03/28 16:26:36]

typo: missing spaces

[Peter Beverloo, 2017/04/07 17:48:22]

What how. Fixed, thanks!

+  ASSERT_TRUE(cryptographer.Decrypt(recipient_public_key, sender_public_key,
+                                    sender_shared_secret, auth_secret, salt,
+                                    ciphertext, record_size, &plaintext));
+
   ASSERT_EQ(kPlaintext, plaintext);
 }
 
-TEST_F(GCMMessageCryptographerReferenceTest, WithoutAuthSecret) {
-  // The 16-byte salt unique to the message.
-  const char kSalt[] = "Qg61ZJRva_XBE9IEUelU3A";
-
-  // The keying material used by the sender to encrypt the |kCiphertext|.
-  const char kSenderPrivate[] =
-      "MIGxMBwGCiqGSIb3DQEMAQMwDgQIFfJ62c9VwXgCAggABIGQkRxDRPQjwuWp1C3-z1pYTDqF"
-      "_NZ1kbPsjmkC3JSv02oAYHtBAtKa2e3oAPqsPfCvoCJBJs6G4WY4EuEO1YFL6RKpNl3DpIUc"
-      "v9ShR27p_je_nyLpNBAxn2drnjlF_K6s4gcJmcvCxuNjAwOlLMPvQqGjOR2K_oMs1Hdq0EKJ"
-      "NwWt3WUVEpuQF_WhYjCVIeGO";
-  const char kSenderPublicUncompressed[] =
-      "BDgpRKok2GZZDmS4r63vbJSUtcQx4Fq1V58-6-3NbZzSTlZsQiCEDTQy3CZ0ZMsqeqsEb7qW"
-      "2blQHA4S48fynTk";
-  const char kSenderPublicX509[] =
-      "MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAEOClEqiTYZlkOZLivre9slJS1xDHgWrVXnz7r"
-      "7c1tnNJOVmxCIIQNNDLcJnRkyyp6qwRvupbZuVAcDhLjx_KdOQ";
-
-  // The keying material used by the client to decrypt the |kCiphertext|.
-  const char kReceiverPrivate[] =
-      "MIGxMBwGCiqGSIb3DQEMAQMwDgQIqMt4d7uJdt4CAggABIGQeikRHE3CqUeF-uUtJno9BL0g"
-      "mNRyDihZe8P3nF_g-NYVzvdQowsXfYeza6OQOdDuMXxnGgNToVy2jsiWVN6rxCaSMTY622y8"
-      "ajW5voSdqC2PakQ8ZNTPNHarLDMC9NpgGKrUh8hfRLhvb7vtbKIWmx-22rQB5yTYdqzN2m7A"
-      "GHMWRnVk0mMzMsMjZqYFaa2D";
-  const char kReceiverPublicUncompressed[] =
-      "BCEkBjzL8Z3C-oi2Q7oE5t2Np-p7osjGLg93qUP0wvqRT21EEWyf0cQDQcakQMqz4hQKYOQ3"
-      "il2nNZct4HgAUQU";
-  const char kReceiverPublicX509[] =
-      "MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAEISQGPMvxncL6iLZDugTm3Y2n6nuiyMYuD3ep"
-      "Q_TC-pFPbUQRbJ_RxANBxqRAyrPiFApg5DeKXac1ly3geABRBQ";
-
-  // The ciphertext and associated plaintext of the message.
-  const char kCiphertext[] = "yqD2bapcx14XxUbtwjiGx69eHE3Yd6AqXcwBpT2Kd1uy";
-  const char kPlaintext[] = "I am the walrus";
-
-  std::string sender_shared_secret, receiver_shared_secret;
-
-  // Compute the shared secrets between the sender and receiver's keys.
-  ASSERT_NO_FATAL_FAILURE(ComputeSharedSecret(
-      kSenderPrivate, kSenderPublicX509, kReceiverPublicUncompressed,
-      &sender_shared_secret));
-  ASSERT_NO_FATAL_FAILURE(ComputeSharedSecret(
-      kReceiverPrivate, kReceiverPublicX509, kSenderPublicUncompressed,
-      &receiver_shared_secret));
-
-  ASSERT_GT(sender_shared_secret.size(), 0u);
-  ASSERT_EQ(sender_shared_secret, receiver_shared_secret);
-
-  std::unique_ptr<GCMMessageCryptographer> cryptographer;
-  ASSERT_NO_FATAL_FAILURE(CreateCryptographer(
-      kReceiverPublicUncompressed, kSenderPublicUncompressed,
-      nullptr /* auth_secret */, &cryptographer));
-
-  std::string salt;
-  ASSERT_TRUE(base::Base64UrlDecode(
-        kSalt, base::Base64UrlDecodePolicy::IGNORE_PADDING, &salt));
-
-  std::string encoded_ciphertext, ciphertext, plaintext;
-  size_t record_size = 0;
-
-  // Verify that encrypting |kPlaintext| yields the expected |kCiphertext|.
-  ASSERT_TRUE(cryptographer->Encrypt(kPlaintext, sender_shared_secret, salt,
-                                     &record_size, &ciphertext));
-
-  base::Base64UrlEncode(ciphertext, base::Base64UrlEncodePolicy::OMIT_PADDING,
-                        &encoded_ciphertext);
-  ASSERT_EQ(kCiphertext, encoded_ciphertext);
-
-  // Verify that decrypting |kCiphertext| yields the expected |kPlaintext|.
-  ASSERT_TRUE(cryptographer->Decrypt(ciphertext, sender_shared_secret, salt,
-                                     record_size, &plaintext));
-  ASSERT_EQ(kPlaintext, plaintext);
-}
-
 }  // namespace gcm