Be strict about input in 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 <memory>
 
 #include "base/base64url.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;
+// Expected sizes of the different input given to the cryptographer.
+constexpr size_t kEcdhSharedSecretSize = 32;
+constexpr size_t kAuthSecretSize = 16;
+constexpr size_t kSaltSize = 16;
 
-// 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 kCommonSenderPublicKey[] =
-    "BAuzSrdIyKZsHnuOhqklkIKi6fl65V9OdPy6nFwI2SywL5-6I5SkkDtfIL9y7NkoEE345jv2Eo"
-    "5n4NIbLJIBjTM";
-const char kCommonAuthSecret[] = "MyAuthenticationSecret";
+// Keying material for both parties as P-256 EC points. Used to make sure that
+// the test vectors are reproducible.
+const unsigned char kCommonSenderPublicKey[] = {
+    0x04, 0x05, 0x3C, 0xA1, 0xB9, 0xA5, 0xAB, 0xB8, 0x2D, 0x88, 0x48,
+    0x82, 0xC9, 0x49, 0x19, 0x91, 0xD5, 0xFD, 0xD1, 0x92, 0xDB, 0xA7,
+    0x7E, 0x70, 0x48, 0x37, 0x41, 0xCD, 0x90, 0x05, 0x80, 0xDF, 0x65,
+    0x9A, 0xA1, 0x1A, 0x04, 0xF1, 0x98, 0x25, 0xF2, 0xC2, 0x13, 0x5D,
+    0xD9, 0x72, 0x35, 0x75, 0x24, 0xF9, 0xFF, 0x25, 0xD1, 0xBC, 0x84,
+    0x46, 0x4E, 0x88, 0x08, 0x55, 0x70, 0x9F, 0xA7, 0x07, 0xD9};
+static_assert(arraysize(kCommonSenderPublicKey) == 65,
+              "Raw P-256 public keys must be 65 bytes in size.");
+
+const unsigned char kCommonRecipientPublicKey[] = {
+    0x04, 0x35, 0x02, 0x67, 0xB9, 0x10, 0x8F, 0x9B, 0xF1, 0x85, 0xF5,
+    0x1B, 0xD7, 0xA4, 0xEF, 0xBD, 0x28, 0xB3, 0x11, 0x40, 0xBA, 0xD0,
+    0xEE, 0xB2, 0x97, 0xDA, 0x6A, 0x93, 0x2D, 0x26, 0x45, 0xBD, 0xB2,
+    0x9A, 0x9F, 0xB8, 0x19, 0xD8, 0x21, 0x6F, 0x66, 0xE3, 0xF6, 0x0B,
+    0x74, 0xB2, 0x28, 0x38, 0xDC, 0xA7, 0x8A, 0x58, 0x0D, 0x56, 0x47,
+    0x3E, 0xD0, 0x5B, 0x5C, 0x93, 0x4E, 0xB3, 0x89, 0x87, 0x64};
+static_assert(arraysize(kCommonRecipientPublicKey) == 65,
+              "Raw P-256 public keys must be 65 bytes in size.");
+
+const unsigned char kCommonRecipientPublicKeyX509[] = {
+    0x30, 0x59, 0x30, 0x13, 0x06, 0x07, 0x2A, 0x86, 0x48, 0xCE, 0x3D, 0x02,
+    0x01, 0x06, 0x08, 0x2A, 0x86, 0x48, 0xCE, 0x3D, 0x03, 0x01, 0x07, 0x03,
+    0x42, 0x00, 0x04, 0x35, 0x02, 0x67, 0xB9, 0x10, 0x8F, 0x9B, 0xF1, 0x85,
+    0xF5, 0x1B, 0xD7, 0xA4, 0xEF, 0xBD, 0x28, 0xB3, 0x11, 0x40, 0xBA, 0xD0,
+    0xEE, 0xB2, 0x97, 0xDA, 0x6A, 0x93, 0x2D, 0x26, 0x45, 0xBD, 0xB2, 0x9A,
+    0x9F, 0xB8, 0x19, 0xD8, 0x21, 0x6F, 0x66, 0xE3, 0xF6, 0x0B, 0x74, 0xB2,
+    0x28, 0x38, 0xDC, 0xA7, 0x8A, 0x58, 0x0D, 0x56, 0x47, 0x3E, 0xD0, 0x5B,
+    0x5C, 0x93, 0x4E, 0xB3, 0x89, 0x87, 0x64};
+
+const unsigned char kCommonRecipientPrivateKey[] = {
+    0x30, 0x81, 0xB0, 0x30, 0x1B, 0x06, 0x0A, 0x2A, 0x86, 0x48, 0x86, 0xF7,
+    0x0D, 0x01, 0x0C, 0x01, 0x03, 0x30, 0x0D, 0x04, 0x08, 0xF3, 0xD6, 0x39,
+    0xB0, 0xBF, 0xC2, 0xF7, 0xEF, 0x02, 0x01, 0x01, 0x04, 0x81, 0x90, 0x0C,
+    0xBC, 0xC9, 0x5F, 0x95, 0x6C, 0x4C, 0x6A, 0x57, 0xC4, 0x04, 0x47, 0x8F,
+    0x59, 0xFD, 0x35, 0x97, 0x3B, 0xF3, 0x66, 0xA7, 0xEB, 0x8D, 0x44, 0x1E,
+    0xCB, 0x4D, 0xFC, 0xD8, 0x8A, 0x38, 0xCA, 0xA8, 0xD7, 0x93, 0x45, 0x61,
+    0xCC, 0xC7, 0xD8, 0x24, 0x16, 0xBF, 0xFC, 0xF4, 0x20, 0x54, 0x53, 0xB1,
+    0x20, 0x3E, 0x19, 0x62, 0x08, 0xBE, 0x3D, 0x5B, 0x56, 0x60, 0x2D, 0x0C,
+    0xDB, 0x29, 0x4A, 0x0B, 0xC8, 0xE0, 0x58, 0xAA, 0xE0, 0xAE, 0xE5, 0x91,
+    0xEA, 0x6E, 0x40, 0x39, 0xD7, 0x3A, 0x1D, 0x75, 0x1E, 0xFF, 0xE3, 0xA7,
+    0x64, 0x53, 0x50, 0x4A, 0xC1, 0xE9, 0x31, 0x9F, 0x0E, 0xB5, 0x12, 0x3E,
+    0x57, 0xD7, 0x96, 0x5D, 0x69, 0xD5, 0x5A, 0xF8, 0x7C, 0x21, 0xF2, 0x43,
+    0x2C, 0x34, 0x11, 0x8C, 0xB4, 0x37, 0x85, 0xB8, 0xDF, 0xFB, 0x5E, 0x68,
+    0xD5, 0xAA, 0xBC, 0x29, 0x2B, 0xE1, 0x8C, 0xA2, 0x76, 0xAA, 0x59, 0x2D,
+    0x8D, 0xB9, 0xC0, 0x11, 0xC8, 0xA9, 0x01, 0xD6, 0xB3, 0xBD, 0xEE};
+
+const unsigned char kCommonAuthSecret[] = {0x25, 0xF2, 0xC2, 0xB8, 0x19, 0xD8,
+                                           0xFD, 0x35, 0x97, 0xDF, 0xFB, 0x5E,
+                                           0xF6, 0x0B, 0xD7, 0xA4};
+static_assert(arraysize(kCommonAuthSecret) == 16,
+              "Auth secrets must be 16 bytes in size.");
 
 // 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 ecdh_shared_secret;
-  const char* const salt;
+  const unsigned char ecdh_shared_secret[kEcdhSharedSecretSize];
+  const unsigned char auth_secret[kAuthSecretSize];
+  const unsigned char salt[kSaltSize];
   size_t record_size;
   const char* const output;
 };
 
 const TestVector kEncryptionTestVectorsDraft03[] = {
     // Simple message.
-    {"Hello, world!", "AhA6n2oFYPWIh-cXwyv1m2C0JvmjHB4ZkXj8QylESXU",
-     "tsJYqAGvFDk6lDEv7daecw", 4096,
-     "FgWrrnZq79oI_N4ORkVLHx1jfVmjeiIk-xFX8PzVuA"},
+    {"Hello, world!",
+     {0x0B, 0x32, 0xE2, 0xD1, 0x6A, 0xBF, 0x4F, 0x2C, 0x49, 0xEA, 0xF7,
+      0x5D, 0x71, 0x7D, 0x89, 0xA9, 0xA7, 0x5E, 0x21, 0xB2, 0xB5, 0x51,
+      0xE6, 0x4C, 0x08, 0x68, 0xD3, 0x6F, 0x8F, 0x72, 0x7E, 0x14},
+     {0xD3, 0xF2, 0x78, 0xBD, 0x8D, 0xDD, 0x84, 0x99, 0x66, 0x08, 0xD7, 0x0F,
+      0xBA, 0x9B, 0x60, 0xFC},
+     {0x15, 0x4A, 0xD7, 0x73, 0x92, 0xBD, 0x3B, 0xCF, 0x6F, 0x98, 0xDC, 0x9B,
+      0x8B, 0x56, 0xFB, 0xBD},
+     4096,
+     "T4SXCyj84drA6wRaBNLGDMzeyOEBWjsIEkS2ros6Aw"},
     // Empty message.
-    {"", "lMyvTong4VR053jfCpWmMDGW5dEDAqiTZUIU-inhTjU",
-     "wH3uvZqcN6oey9whiGpn1A", 4096, "MTI9zZ8CJTUzbZ4qNDoQZs0k"},
-    // Message with an invalid salt size.
-    {
-        "Hello, world!", "CcdxzkR6z1EY9vSrM7_IxYVxDxu46hV638EZQTPd7XI",
-        "aRr1fI1YSGVi5XU", 4096,
-        nullptr  // expected to fail
-    }};
+    {"",
+     {0x3F, 0xD8, 0x95, 0x2C, 0xA2, 0x11, 0xBD, 0x7B, 0x57, 0xB2, 0x00,
+      0xBD, 0x57, 0x68, 0x3F, 0xF0, 0x14, 0x57, 0x5F, 0xB1, 0x9F, 0x15,
+      0x4F, 0x11, 0xF0, 0x4D, 0xA2, 0xE8, 0x4C, 0xEA, 0x74, 0x3B},
+     {0xB1, 0xE1, 0xC7, 0x32, 0x4C, 0xAA, 0x56, 0x32, 0x68, 0x20, 0x0F, 0x26,
+      0x3F, 0x48, 0x4D, 0x99},
+     {0xE9, 0x39, 0x45, 0xBC, 0x96, 0x96, 0x88, 0x76, 0xFC, 0xA1, 0xAD, 0xE4,
+      0x9D, 0x28, 0xF3, 0x73},
+     4096,
+     "8s-Tzq8Cn_eobL6uEcNDXL7K"}};
 
 const TestVector kDecryptionTestVectorsDraft03[] = {
     // Simple message.
-    {"ceiEu_YpmqLoakD4smdzvy2XKRQrJ9vBzB2aqYEfzw",
-     "47ZytAw9qHlm-Q8g-7rH81rUPzaCgGcoFvlS1qxQtQk", "EuR7EVetcaWpndXd_dKeyA",
-     4096, "Hello, world!"},
+    {"lsemWwzlFoJzoidHCnVuxRiJpotTcYokJHKzmQ2FsA",
+     {0x4D, 0x3A, 0x6C, 0xBA, 0xD8, 0x1D, 0x8E, 0x68, 0x8B, 0xE6, 0x76,
+      0xA7, 0xFF, 0x60, 0xC7, 0xFE, 0x77, 0xE2, 0x6D, 0x37, 0xF6, 0x12,
+      0x44, 0xE2, 0x25, 0xFE, 0xE1, 0xD8, 0xCF, 0x8A, 0xA8, 0x33},
+     {0x62, 0x36, 0xAC, 0xCA, 0x74, 0xD4, 0x49, 0x49, 0x6B, 0x27, 0xB4, 0xF7,
+      0xC1, 0xE5, 0x30, 0x9A},
+     {0x1C, 0xA7, 0xFD, 0x98, 0x1A, 0xE4, 0xA7, 0x92, 0xE1, 0xB6, 0xA1, 0xE3,
+      0x41, 0x63, 0x87, 0x76},
+     4096,
+     "Hello, world!"},
     // Simple message with 16 bytes of padding.
-    {"WSf6fz1O0aIJyaPTCnvk83OqIQxsRKeFOvblPLsPpFB_1AV9ROk09TE1cGrB6zQ",
-     "MYSsNybwrTzRIzQYUq_yFPc6ugcTrJdEZJDM4NswvUg", "8sEAMQYnufo2UkKl80cUGQ",
-     4096, "Hello, world!"},
+    {"VQB6Ds-q9xRqyM1tj_gksSgc78vCWEhphZ-NF1E7_yMfPuRRZlC_Xt9_2NsX3SU",
+     {0x8B, 0x38, 0x8E, 0x22, 0xD5, 0xC4, 0xFD, 0x65, 0x8A, 0xBB, 0xD9,
+      0x58, 0xBD, 0xF5, 0xFF, 0x79, 0xCF, 0x9D, 0xBD, 0x87, 0x16, 0x7E,
+      0x93, 0x84, 0x20, 0x8E, 0x8D, 0x49, 0x41, 0x7D, 0x8E, 0x8F},
+     {0x3E, 0x65, 0xC7, 0x1F, 0x75, 0x7A, 0x43, 0xC4, 0x78, 0x6C, 0x64, 0x99,
+      0x49, 0xA0, 0xC4, 0xB2},
+     {0x43, 0x4D, 0x30, 0x8E, 0xE4, 0x76, 0xB5, 0xD0, 0x87, 0xFC, 0x04, 0xD1,
+      0x2E, 0x35, 0x75, 0x63},
+     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
-    },
+    {"xU8a499UHB_-YSV4VOm-JZnT",
+     {0x68, 0x72, 0x3D, 0x13, 0xE7, 0x50, 0xFA, 0x3E, 0xA0, 0x59, 0x33,
+      0xF1, 0x73, 0xA8, 0xE8, 0xCD, 0x8D, 0xD4, 0x3C, 0xDC, 0xDE, 0x06,
+      0x35, 0x5F, 0x51, 0xBB, 0xB2, 0x57, 0x97, 0x72, 0x9D, 0xFB},
+     {0x84, 0xB2, 0x2A, 0xE7, 0xC6, 0xC0, 0xCE, 0x5F, 0xAD, 0x37, 0x06, 0x7F,
+      0xD1, 0xFD, 0x10, 0x87},
+     {0x9B, 0xC5, 0x8D, 0x5F, 0xD6, 0xD2, 0xA6, 0xBD, 0xAF, 0x4B, 0xD9, 0x60,
+      0xC6, 0xB4, 0x50, 0x0F},
+     4096,
+     ""},
     // Message with an invalid record size.
-    {
-        "iGrOpmJC5XTTf7wtgdhZ_qT",
-        "kR5BMfqMKOD1yrLKE2giObXHI7merrMtnoO2oqneqXA", "SQeJSPrqHvTdSfAMF8bBzQ",
-        8,
-        nullptr  // expected to fail
-    },
+    {"gfB-_edj7qEVokyVHpkDJN6FVKHnlWs1RCDw5bmrwQ",
+     {0x5F, 0xE1, 0x7C, 0x4B, 0xFF, 0x04, 0xBF, 0x2C, 0x70, 0x67, 0xFA,
+      0xF8, 0xB0, 0x07, 0x4F, 0xF6, 0x3C, 0x03, 0x6F, 0xBE, 0xA1, 0x1F,
+      0x4B, 0x99, 0x25, 0x4F, 0xB9, 0x5F, 0xC4, 0x78, 0x76, 0xDE},
+     {0x59, 0xAB, 0x45, 0xFC, 0x6A, 0xF5, 0xB3, 0xE0, 0xF5, 0x40, 0xD7, 0x98,
+      0x0F, 0xF0, 0xA4, 0xCB},
+     {0xDB, 0xA0, 0xF2, 0x91, 0x8D, 0x50, 0x42, 0xE0, 0x17, 0x68, 0x5B, 0x9B,
+      0xF2, 0xA2, 0xC3, 0xF9},
+     7,
+     nullptr},
+    // Message with four bytes of invalid, non-zero padding.
+    {"2FJmrF95yVU8Q8cYQy9OoOwCb59ZoRlxazPE0T-MNOSMbr0",
+     {0x6B, 0x82, 0x92, 0xD3, 0x71, 0x9A, 0x97, 0x76, 0x45, 0x11, 0x99,
+      0x6D, 0xBF, 0x56, 0xCC, 0x81, 0x98, 0x56, 0x80, 0xF5, 0x78, 0x36,
+      0xD6, 0x43, 0x95, 0x68, 0xDB, 0x0F, 0x23, 0x39, 0xF3, 0x6E},
+     {0x02, 0x16, 0xDC, 0xC3, 0xDE, 0x2C, 0xB5, 0x08, 0x89, 0xDB, 0xD8, 0x18,
+      0x68, 0x83, 0x1C, 0xDB},
+     {0xB7, 0x85, 0x5D, 0x8E, 0x84, 0xC3, 0x2D, 0x61, 0x9B, 0x78, 0x3B, 0x60,
+      0x0E, 0x70, 0x84, 0xF3},
+     4096,
+     nullptr},
     // Message with multiple (2) records.
-    {
-        "RqQVHRXlfYjzW9xhzh3V_KijLKjZiKzGXosqN_"
-        "IaMzi0zI0tXXhC1urtrk3iWRoqttNXpkD2r"
-        "UCgLy8A1FnTjw",
-        "W3W4gx7sqcfmBnvNNdO9d4MBCC1bvJkvsNjZOGD-CCg", "xG0TPGi9aIcxjpXKmaYBBQ",
-        7,
-        nullptr  // expected to fail
-    }};
+    {"reI6sW6y67FI8Kxk-x9GNwiu77His_f5GioDBiKS7IzjDQ",
+     {0xC6, 0x16, 0x6F, 0xAF, 0xE1, 0xB6, 0x8F, 0x2B, 0x0F, 0x67, 0x5A,
+      0xC7, 0xAC, 0x7E, 0xF6, 0x7C, 0x33, 0xA2, 0xA1, 0x11, 0xB0, 0xB0,
+      0xAB, 0xAC, 0x37, 0x61, 0xF4, 0xCB, 0x98, 0xFF, 0x00, 0x51},
+     {0xAE, 0xDA, 0x86, 0xDF, 0x6B, 0x03, 0x88, 0xDE, 0x90, 0xBB, 0xB7, 0xA0,
+      0x78, 0x91, 0x3A, 0x36},
+     {0x4C, 0x4E, 0x2A, 0x8D, 0x88, 0x82, 0xCF, 0xC2, 0xF9, 0x8A, 0xFD, 0x31,
+      0xF8, 0xD1, 0xF6, 0xB5},
+     8,
+     nullptr}};
 
 }  // 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_));
+    recipient_public_key_.assign(
+        kCommonRecipientPublicKey,
+        kCommonRecipientPublicKey + arraysize(kCommonRecipientPublicKey));
+    sender_public_key_.assign(
+        kCommonSenderPublicKey,
+        kCommonSenderPublicKey + arraysize(kCommonSenderPublicKey));
 
-    std::unique_ptr<crypto::SymmetricKey> random_key(
-        crypto::SymmetricKey::GenerateRandomKey(crypto::SymmetricKey::AES,
-                                                kKeySizeBits));
+    std::string recipient_private_key(
+        kCommonRecipientPrivateKey,
+        kCommonRecipientPrivateKey + arraysize(kCommonRecipientPrivateKey));
 
-    ASSERT_TRUE(random_key->GetRawKey(&ecdh_shared_secret_));
+    // TODO(peter): Remove the dependency on the x509 keying material when
+    // crbug.com/618025 has been resolved.
+    std::string recipient_public_key_x509(
+        kCommonRecipientPublicKeyX509,
+        kCommonRecipientPublicKeyX509 +
+            arraysize(kCommonRecipientPublicKeyX509));
+
+    ASSERT_TRUE(ComputeSharedP256Secret(
+        recipient_private_key, recipient_public_key_x509, sender_public_key_,
+        &ecdh_shared_secret_));
+
+    auth_secret_.assign(kCommonAuthSecret,
+                        kCommonAuthSecret + arraysize(kCommonAuthSecret));
   }
 
  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;
   }
 
   // Public keys of the recipient and sender as uncompressed P-256 EC points.
   std::string recipient_public_key_;
   std::string sender_public_key_;
 
-  // Shared secret to use in transformations. Unrelated to the keys above.
+  // Shared secret to use in transformations. Associated with the keys above.
   std::string ecdh_shared_secret_;
 
+  // Authentication secret to use in tests where no specific value is expected.
+  std::string auth_secret_;
+
   // The GCMMessageCryptographer instance to use for the tests.
   std::unique_ptr<GCMMessageCryptographer> cryptographer_;
 };
 
 TEST_F(GCMMessageCryptographerTest, RoundTrip) {
   const std::string salt = GenerateRandomSalt();
 
   size_t record_size = 0;
 
   std::string ciphertext, plaintext;
   ASSERT_TRUE(cryptographer_->Encrypt(
       recipient_public_key_, sender_public_key_, ecdh_shared_secret_,
-      kCommonAuthSecret, salt, kExamplePlaintext, &record_size, &ciphertext));
+      auth_secret_, salt, kExamplePlaintext, &record_size, &ciphertext));
 
   EXPECT_GT(record_size, ciphertext.size() - 16);
   EXPECT_GT(ciphertext.size(), 0u);
 
-  ASSERT_TRUE(cryptographer_->Decrypt(
-      recipient_public_key_, sender_public_key_, ecdh_shared_secret_,
-      kCommonAuthSecret, salt, ciphertext, record_size, &plaintext));
+  ASSERT_TRUE(cryptographer_->Decrypt(recipient_public_key_, sender_public_key_,
+                                      ecdh_shared_secret_, auth_secret_, 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(
-      recipient_public_key_, sender_public_key_, ecdh_shared_secret_,
-      kCommonAuthSecret, salt, message, &record_size, &ciphertext));
+  ASSERT_TRUE(cryptographer_->Encrypt(recipient_public_key_, sender_public_key_,
+                                      ecdh_shared_secret_, auth_secret_, salt,
+                                      message, &record_size, &ciphertext));
 
   EXPECT_GT(record_size, ciphertext.size() - 16);
   EXPECT_GT(ciphertext.size(), 0u);
 
-  ASSERT_TRUE(cryptographer_->Decrypt(
-      recipient_public_key_, sender_public_key_, ecdh_shared_secret_,
-      kCommonAuthSecret, salt, ciphertext, record_size, &plaintext));
+  ASSERT_TRUE(cryptographer_->Decrypt(recipient_public_key_, sender_public_key_,
+                                      ecdh_shared_secret_, auth_secret_, 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(
       recipient_public_key_, sender_public_key_, ecdh_shared_secret_,
-      kCommonAuthSecret, salt, kExamplePlaintext, &record_size, &ciphertext));
+      auth_secret_, salt, kExamplePlaintext, &record_size, &ciphertext));
 
   EXPECT_GT(record_size, ciphertext.size() - 16);
 
   EXPECT_FALSE(cryptographer_->Decrypt(
       recipient_public_key_, sender_public_key_, ecdh_shared_secret_,
-      kCommonAuthSecret, salt, ciphertext, 0 /* record_size */, &plaintext));
+      auth_secret_, salt, ciphertext, 0 /* record_size */, &plaintext));
 
   EXPECT_FALSE(cryptographer_->Decrypt(
       recipient_public_key_, sender_public_key_, ecdh_shared_secret_,
-      kCommonAuthSecret, salt, ciphertext, ciphertext.size() - 17, &plaintext));
+      auth_secret_, 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));
+      auth_secret_, 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_->encryption_scheme_->DerivePseudoRandomKey(
-          ecdh_shared_secret_, kCommonAuthSecret);
+          ecdh_shared_secret_, auth_secret_);
   const std::string content_encryption_key =
       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_->TransformRecord(
       GCMMessageCryptographer::Direction::ENCRYPT, message,
       content_encryption_key, nonce, &ciphertext));
 
-  ASSERT_TRUE(cryptographer_->Decrypt(
-      recipient_public_key_, sender_public_key_, ecdh_shared_secret_,
-      kCommonAuthSecret, salt, ciphertext, record_size, &plaintext));
+  ASSERT_TRUE(cryptographer_->Decrypt(recipient_public_key_, sender_public_key_,
+                                      ecdh_shared_secret_, auth_secret_, 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_->TransformRecord(
       GCMMessageCryptographer::Direction::ENCRYPT, message,
       content_encryption_key, nonce, &ciphertext));
 
   ASSERT_FALSE(cryptographer_->Decrypt(
       recipient_public_key_, sender_public_key_, ecdh_shared_secret_,
-      kCommonAuthSecret, salt, ciphertext, record_size, &plaintext));
+      auth_secret_, 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_->TransformRecord(
       GCMMessageCryptographer::Direction::ENCRYPT, message,
       content_encryption_key, nonce, &ciphertext));
 
   ASSERT_FALSE(cryptographer_->Decrypt(
       recipient_public_key_, sender_public_key_, ecdh_shared_secret_,
-      kCommonAuthSecret, salt, ciphertext, record_size, &plaintext));
+      auth_secret_, 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_->TransformRecord(
       GCMMessageCryptographer::Direction::ENCRYPT, message,
       content_encryption_key, nonce, &ciphertext));
 
   ASSERT_FALSE(cryptographer_->Decrypt(
       recipient_public_key_, sender_public_key_, ecdh_shared_secret_,
-      kCommonAuthSecret, salt, ciphertext, record_size, &plaintext));
+      auth_secret_, salt, ciphertext, record_size, &plaintext));
 }
 
 TEST_F(GCMMessageCryptographerTest, AuthSecretAffectsPRK) {
+  std::string first_auth_secret, second_auth_secret;
+
+  crypto::RandBytes(base::WriteInto(&first_auth_secret, kAuthSecretSize + 1),
+                    kAuthSecretSize);
+  crypto::RandBytes(base::WriteInto(&second_auth_secret, kAuthSecretSize + 1),
+                    kAuthSecretSize);
+
   ASSERT_NE(cryptographer_->encryption_scheme_->DerivePseudoRandomKey(
-                ecdh_shared_secret_, "Hello"),
+                ecdh_shared_secret_, first_auth_secret),
             cryptographer_->encryption_scheme_->DerivePseudoRandomKey(
-                ecdh_shared_secret_, "World"));
+                ecdh_shared_secret_, second_auth_secret));
 
   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;
+  size_t first_record_size, second_record_size;
+  std::string first_ciphertext, second_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_, first_auth_secret,
+                                      salt, kExamplePlaintext,
+                                      &first_record_size, &first_ciphertext));
 
-  ASSERT_TRUE(cryptographer_->Encrypt(
-      recipient_public_key_, sender_public_key_, ecdh_shared_secret_, "World",
-      salt, kExamplePlaintext, &world_record_size, &world_ciphertext));
+  ASSERT_TRUE(cryptographer_->Encrypt(recipient_public_key_, sender_public_key_,
+                                      ecdh_shared_secret_, second_auth_secret,
+                                      salt, kExamplePlaintext,
+                                      &second_record_size, &second_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);
+  ASSERT_NE(first_ciphertext, second_ciphertext);
+  EXPECT_EQ(first_record_size, second_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;
+  std::string first_plaintext, second_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_, first_auth_secret,
+                                      salt, first_ciphertext, first_record_size,
+                                      &first_plaintext));
 
-  ASSERT_TRUE(cryptographer_->Decrypt(
-      recipient_public_key_, sender_public_key_, ecdh_shared_secret_, "World",
-      salt, world_ciphertext, world_record_size, &world_plaintext));
+  ASSERT_TRUE(cryptographer_->Decrypt(recipient_public_key_, sender_public_key_,
+                                      ecdh_shared_secret_, second_auth_secret,
+                                      salt, second_ciphertext,
+                                      second_record_size, &second_plaintext));
 
-  EXPECT_EQ(kExamplePlaintext, hello_plaintext);
-  EXPECT_EQ(kExamplePlaintext, world_plaintext);
+  EXPECT_EQ(kExamplePlaintext, first_plaintext);
+  EXPECT_EQ(kExamplePlaintext, second_plaintext);
 }
 
 class GCMMessageCryptographerTestVectorTest
     : public GCMMessageCryptographerTest {};
 
 TEST_F(GCMMessageCryptographerTestVectorTest, EncryptionVectorsDraft03) {
-  std::string ecdh_shared_secret, salt, output, ciphertext;
+  std::string ecdh_shared_secret, auth_secret, salt, ciphertext, output;
   size_t record_size = 0;
 
   for (size_t i = 0; i < arraysize(kEncryptionTestVectorsDraft03); ++i) {
     SCOPED_TRACE(i);
 
-    ASSERT_TRUE(base::Base64UrlDecode(
+    ecdh_shared_secret.assign(
         kEncryptionTestVectorsDraft03[i].ecdh_shared_secret,
-        base::Base64UrlDecodePolicy::IGNORE_PADDING, &ecdh_shared_secret));
-    ASSERT_TRUE(base::Base64UrlDecode(
-        kEncryptionTestVectorsDraft03[i].salt,
-        base::Base64UrlDecodePolicy::IGNORE_PADDING, &salt));
+        kEncryptionTestVectorsDraft03[i].ecdh_shared_secret +
+            kEcdhSharedSecretSize);
 
-    const bool has_output = kEncryptionTestVectorsDraft03[i].output;
-    const bool result = cryptographer_->Encrypt(
+    auth_secret.assign(
+        kEncryptionTestVectorsDraft03[i].auth_secret,
+        kEncryptionTestVectorsDraft03[i].auth_secret + kAuthSecretSize);
+
+    salt.assign(kEncryptionTestVectorsDraft03[i].salt,
+                kEncryptionTestVectorsDraft03[i].salt + kSaltSize);
+
+    ASSERT_TRUE(cryptographer_->Encrypt(
         recipient_public_key_, sender_public_key_, ecdh_shared_secret,
-        kCommonAuthSecret, salt, kEncryptionTestVectorsDraft03[i].input,
-        &record_size, &ciphertext);
+        auth_secret, salt, kEncryptionTestVectorsDraft03[i].input, &record_size,
+        &ciphertext));
 
-    if (!has_output) {
-      EXPECT_FALSE(result);
-      continue;
-    }
-
-    EXPECT_TRUE(result);
-    ASSERT_TRUE(base::Base64UrlDecode(
-        kEncryptionTestVectorsDraft03[i].output,
-        base::Base64UrlDecodePolicy::IGNORE_PADDING, &output));
+    base::Base64UrlEncode(ciphertext, base::Base64UrlEncodePolicy::OMIT_PADDING,
+                          &output);
 
     EXPECT_EQ(kEncryptionTestVectorsDraft03[i].record_size, record_size);
-    EXPECT_EQ(output, ciphertext);
+    EXPECT_EQ(kEncryptionTestVectorsDraft03[i].output, output);
   }
 }
 
 TEST_F(GCMMessageCryptographerTestVectorTest, DecryptionVectorsDraft03) {
-  std::string input, ecdh_shared_secret, salt, plaintext;
+  std::string input, ecdh_shared_secret, auth_secret, salt, plaintext;
   for (size_t i = 0; i < arraysize(kDecryptionTestVectorsDraft03); ++i) {
     SCOPED_TRACE(i);
 
     ASSERT_TRUE(base::Base64UrlDecode(
         kDecryptionTestVectorsDraft03[i].input,
         base::Base64UrlDecodePolicy::IGNORE_PADDING, &input));
-    ASSERT_TRUE(base::Base64UrlDecode(
+
+    ecdh_shared_secret.assign(
         kDecryptionTestVectorsDraft03[i].ecdh_shared_secret,
-        base::Base64UrlDecodePolicy::IGNORE_PADDING, &ecdh_shared_secret));
-    ASSERT_TRUE(base::Base64UrlDecode(
-        kDecryptionTestVectorsDraft03[i].salt,
-        base::Base64UrlDecodePolicy::IGNORE_PADDING, &salt));
+        kDecryptionTestVectorsDraft03[i].ecdh_shared_secret +
+            kEcdhSharedSecretSize);
+
+    auth_secret.assign(
+        kDecryptionTestVectorsDraft03[i].auth_secret,
+        kDecryptionTestVectorsDraft03[i].auth_secret + kAuthSecretSize);
+
+    salt.assign(kDecryptionTestVectorsDraft03[i].salt,
+                kDecryptionTestVectorsDraft03[i].salt + kSaltSize);
 
     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);
+        auth_secret, salt, input, kDecryptionTestVectorsDraft03[i].record_size,
+        &plaintext);
 
     if (!has_output) {
       EXPECT_FALSE(result);
       continue;
     }
 
     EXPECT_TRUE(result);
     EXPECT_EQ(kDecryptionTestVectorsDraft03[i].output, plaintext);
   }
 }
@@ skipping 109 matching lines @@
 
   // And verify that decrypting the message yields the plaintext again.
   ASSERT_TRUE(cryptographer.Decrypt(recipient_public_key, sender_public_key,
                                     sender_shared_secret, auth_secret, salt,
                                     ciphertext, record_size, &plaintext));
 
   ASSERT_EQ(kPlaintext, plaintext);
 }
 
 }  // namespace gcm