Add support for encrypted WebM files as defined in the RFC.

media/crypto/aes_decryptor_unittest.cc

 // Copyright (c) 2012 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 <string>
 
+#include "base/logging.h"
+#include "base/sys_byteorder.h"
 #include "media/base/decoder_buffer.h"
 #include "media/base/decrypt_config.h"
 #include "media/crypto/aes_decryptor.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace media {
 
-// |kEncryptedData| is encrypted from |kOriginalData| using |kRightKey|, whose
-// length is |kKeySize|. Modifying any of these independently would fail the
-// test.
-static const char kOriginalData[] = "Original data.";
-static const int kEncryptedDataSize = 16;
-static const unsigned char kEncryptedData[] =
-    "\x82\x3A\x76\x92\xEC\x7F\xF8\x85\xEC\x23\x52\xFB\x19\xB1\xB9\x09";
+struct WebmEncryptedData {
+  uint8 plain_text[32];
+  int plain_text_size;
+  uint8 key_id[32];
+  int key_id_size;
+  uint8 key[32];
+  int key_size;
+  uint8 encrypted_data[64];
+  int encrypted_data_size;
+};
+
+const WebmEncryptedData kEncryptedFrames[] = {
+  {
+    // plaintext
+    "Original data.", 14,
+    // key_id
+    { 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b,
+      0x0c, 0x0d, 0x0e, 0x0f, 0x10, 0x11, 0x12, 0x13}, 20,
+    // key
+    { 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
+      0x20, 0x21, 0x22, 0x23}, 16,
+    // encrypted_data
+    { 0xfb, 0xe7, 0x1d, 0xbb, 0x4c, 0x23, 0xce, 0xba, 0xcc, 0xf8, 0xda, 0xc0,
+      0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x99, 0xaa, 0xff, 0xb7,
+      0x74, 0x02, 0x4e, 0x1c, 0x75, 0x3d, 0xee, 0xcb, 0x64, 0xf7}, 34
+  },
+  {
+    // plaintext
+    "Changed Original data.", 22,
+    // key_id
+    { 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b,
+      0x0c, 0x0d, 0x0e, 0x0f, 0x10, 0x11, 0x12, 0x13}, 20,
+    // key
+    { 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
+      0x20, 0x21, 0x22, 0x23}, 16,
+    // encrypted_data
+    { 0x43, 0xe4, 0x78, 0x7a, 0x43, 0xe1, 0x49, 0xbb, 0x44, 0x38, 0xdf, 0xfc,
+      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xec, 0x8e, 0x87, 0x21,
+      0xd3, 0xb9, 0x1c, 0x61, 0xf6, 0x5a, 0x60, 0xaa, 0x07, 0x0e, 0x96, 0xd0,
+      0x54, 0x5d, 0x35, 0x9a, 0x4a, 0xd3}, 42
+  },
+  {
+    // plaintext
+    "Original data.", 14,
+    // key_id
+    { 0x24, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,
+      0x30}, 13,
+    // key
+    { 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3a, 0x3b, 0x3c,
+      0x3d, 0x3e, 0x3f, 0x40}, 16,
+    // encrypted_data
+    { 0xd9, 0x43, 0x30, 0xfd, 0x82, 0x77, 0x62, 0x04, 0x08, 0xc2, 0x48, 0x89,
+      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x48, 0x5e, 0x4a, 0x41,
+      0x2a, 0x8b, 0xf4, 0xc6, 0x47, 0x54, 0x90, 0x34, 0xf4, 0x8b}, 34
+  },
+};
+
+static const int kIntegrityCheckSize = 12;
+static const int kIvSize = 8;
 static const int kKeySize = 16;
-static const unsigned char kRightKey[] = "A wonderful key!";
 static const unsigned char kWrongKey[] = "I'm a wrong key.";
-static const int kKeyIdSize = 9;
-static const unsigned char kKeyId1[] = "Key ID 1.";
-static const unsigned char kKeyId2[] = "Key ID 2.";
-
-class AesDecryptorTest : public testing::Test {
+static const unsigned char kFrame0InvalidHmac[] = {
+  0xfc, 0xe7, 0x1d, 0xbb, 0x4c, 0x23, 0xce, 0xba, 0xcc, 0xf8, 0xda, 0xc0, 0xff,
+  0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x99, 0xaa, 0xff, 0xb7, 0x74, 0x02,
+  0x4e, 0x1c, 0x75, 0x3d, 0xee, 0xcb, 0x64, 0xf7
+};
+static const unsigned char kFrame0InvalidIv[] = {
+  0xfb, 0xe7, 0x1d, 0xbb, 0x4c, 0x23, 0xce, 0xba, 0xcc, 0xf8, 0xda, 0xc0, 0x0f,
+  0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x99, 0xaa, 0xff, 0xb7, 0x74, 0x02,
+  0x4e, 0x1c, 0x75, 0x3d, 0xee, 0xcb, 0x64, 0xf7
+};
+static const unsigned char kFrame0InvalidData[] = {
+  0xfb, 0xe7, 0x1d, 0xbb, 0x4c, 0x23, 0xce, 0xba, 0xcc, 0xf8, 0xda, 0xc0, 0xff,
+  0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x99, 0xaa, 0xff, 0xb7, 0x74, 0x02,
+  0x4e, 0x1c, 0x75, 0x3d, 0xee, 0xcb, 0x64, 0xf8
+};
+
+class HmacAesDecryptorTest : public testing::Test {
  public:
-  AesDecryptorTest() {
-    encrypted_data_ = DecoderBuffer::CopyFrom(
-        kEncryptedData, kEncryptedDataSize);
+  HmacAesDecryptorTest() {}
+
+ protected:
+  scoped_refptr<DecoderBuffer> CreateEncryptedBuffer(const uint8* data,
+                                                     int data_size,
+                                                     const uint8* key_id,
+                                                     int key_id_size) {
+    CHECK_GT(data_size, kIntegrityCheckSize + kIvSize);
+    scoped_refptr<DecoderBuffer> encrypted_buffer = DecoderBuffer::CopyFrom(
+        data + kIntegrityCheckSize, data_size - kIntegrityCheckSize);
+    CHECK(encrypted_buffer);
+
+    // Every encrypted Block has an HMAC and IV prepended to it. Current WebM
+    // encrypted request for comments specification is here
+    // http://wiki.webmproject.org/encryption/webm-encryption-rfc
+    uint64 network_iv;
+    memcpy(&network_iv,
+           data + kIntegrityCheckSize,
+           sizeof(network_iv));
+    const uint64 iv = base::NetToHost64(network_iv);
+    encrypted_buffer->SetDecryptConfig(
+        scoped_ptr<DecryptConfig>(new DecryptConfig(
+            data, kIntegrityCheckSize,
+            reinterpret_cast<const uint8*>(&iv), sizeof(iv),
+            key_id, key_id_size,
+            sizeof(iv))));
+    return encrypted_buffer;
   }
 
- protected:
-  void SetKeyIdForEncryptedData(const uint8* key_id, int key_id_size) {
-    encrypted_data_->SetDecryptConfig(
-        scoped_ptr<DecryptConfig>(new DecryptConfig(key_id, key_id_size)));
+  void DecryptAndExpectToSucceed(const uint8* data, int data_size,
+                                 const uint8* plain_text,
+                                 int plain_text_size,
+                                 const uint8* key_id, int key_id_size) {
+    scoped_refptr<DecoderBuffer> encrypted_data =
+        CreateEncryptedBuffer(data, data_size, key_id, key_id_size);
+    scoped_refptr<DecoderBuffer> decrypted =
+        decryptor_.Decrypt(encrypted_data);
+    ASSERT_TRUE(decrypted);
+    ASSERT_EQ(plain_text_size, decrypted->GetDataSize());
+    EXPECT_EQ(0, memcmp(plain_text, decrypted->GetData(), plain_text_size));
   }
 
-  void DecryptAndExpectToSucceed() {
+  void DecryptAndExpectToFail(const uint8* data, int data_size,
+                              const uint8* plain_text, int plain_text_size,
+                              const uint8* key_id, int key_id_size) {
+    scoped_refptr<DecoderBuffer> encrypted_data =
+        CreateEncryptedBuffer(data, data_size, key_id, key_id_size);
     scoped_refptr<DecoderBuffer> decrypted =
-        decryptor_.Decrypt(encrypted_data_);
-    ASSERT_TRUE(decrypted);
-    int data_length = sizeof(kOriginalData) - 1;
-    ASSERT_EQ(data_length, decrypted->GetDataSize());
-    EXPECT_EQ(0, memcmp(kOriginalData, decrypted->GetData(), data_length));
-  }
-
-  void DecryptAndExpectToFail() {
-    scoped_refptr<DecoderBuffer> decrypted =
-        decryptor_.Decrypt(encrypted_data_);
+        decryptor_.Decrypt(encrypted_data);
     EXPECT_FALSE(decrypted);
   }
 
-  scoped_refptr<DecoderBuffer> encrypted_data_;
-  AesDecryptor decryptor_;
-};
-
-TEST_F(AesDecryptorTest, NormalDecryption) {
-  decryptor_.AddKey(kKeyId1, kKeyIdSize, kRightKey, kKeySize);
-  SetKeyIdForEncryptedData(kKeyId1, kKeyIdSize);
-  ASSERT_NO_FATAL_FAILURE(DecryptAndExpectToSucceed());
-}
-
-TEST_F(AesDecryptorTest, WrongKey) {
-  decryptor_.AddKey(kKeyId1, kKeyIdSize, kWrongKey, kKeySize);
-  SetKeyIdForEncryptedData(kKeyId1, kKeyIdSize);
-  ASSERT_NO_FATAL_FAILURE(DecryptAndExpectToFail());
-}
-
-TEST_F(AesDecryptorTest, MultipleKeys) {
-  decryptor_.AddKey(kKeyId1, kKeyIdSize, kRightKey, kKeySize);
-  decryptor_.AddKey(kKeyId2, kKeyIdSize, kWrongKey, kKeySize);
-  SetKeyIdForEncryptedData(kKeyId1, kKeyIdSize);
-  ASSERT_NO_FATAL_FAILURE(DecryptAndExpectToSucceed());
-}
-
-TEST_F(AesDecryptorTest, KeyReplacement) {
-  SetKeyIdForEncryptedData(kKeyId1, kKeyIdSize);
-  decryptor_.AddKey(kKeyId1, kKeyIdSize, kWrongKey, kKeySize);
-  ASSERT_NO_FATAL_FAILURE(DecryptAndExpectToFail());
-  decryptor_.AddKey(kKeyId1, kKeyIdSize, kRightKey, kKeySize);
-  ASSERT_NO_FATAL_FAILURE(DecryptAndExpectToSucceed());
+  HmacAesDecryptor decryptor_;
+};
+
+TEST_F(HmacAesDecryptorTest, NormalDecryption) {
+  const WebmEncryptedData& frame = kEncryptedFrames[0];
+  decryptor_.AddKey(frame.key_id, frame.key_id_size,
+                    frame.key, frame.key_size);
+  ASSERT_NO_FATAL_FAILURE(DecryptAndExpectToSucceed(frame.encrypted_data,
+                                                    frame.encrypted_data_size,
+                                                    frame.plain_text,
+                                                    frame.plain_text_size,
+                                                    frame.key_id,
+                                                    frame.key_id_size));
+}
+
+TEST_F(HmacAesDecryptorTest, WrongKey) {
+  const WebmEncryptedData& frame = kEncryptedFrames[0];
+  decryptor_.AddKey(frame.key_id, frame.key_id_size,
+                    kWrongKey, kKeySize);
+  ASSERT_NO_FATAL_FAILURE(DecryptAndExpectToFail(frame.encrypted_data,
+                                                 frame.encrypted_data_size,
+                                                 frame.plain_text,
+                                                 frame.plain_text_size,
+                                                 frame.key_id,
+                                                 frame.key_id_size));
+}
+
+TEST_F(HmacAesDecryptorTest, MultipleKeys) {
+  const WebmEncryptedData& frame = kEncryptedFrames[0];
+  decryptor_.AddKey(frame.key_id, frame.key_id_size,
+                    frame.key, frame.key_size);
+  const WebmEncryptedData& frame2 = kEncryptedFrames[2];
+  decryptor_.AddKey(frame2.key_id, frame2.key_id_size,
+                    frame2.key, frame2.key_size);
+  ASSERT_NO_FATAL_FAILURE(DecryptAndExpectToSucceed(frame.encrypted_data,
+                                                    frame.encrypted_data_size,
+                                                    frame.plain_text,
+                                                    frame.plain_text_size,
+                                                    frame.key_id,
+                                                    frame.key_id_size));
+}
+
+TEST_F(HmacAesDecryptorTest, KeyReplacement) {
+  const WebmEncryptedData& frame = kEncryptedFrames[0];
+  decryptor_.AddKey(frame.key_id, frame.key_id_size,
+                    kWrongKey, kKeySize);
+  ASSERT_NO_FATAL_FAILURE(DecryptAndExpectToFail(frame.encrypted_data,
+                                                 frame.encrypted_data_size,
+                                                 frame.plain_text,
+                                                 frame.plain_text_size,
+                                                 frame.key_id,
+                                                 frame.key_id_size));
+  decryptor_.AddKey(frame.key_id, frame.key_id_size,
+                    frame.key, frame.key_size);
+  ASSERT_NO_FATAL_FAILURE(DecryptAndExpectToSucceed(frame.encrypted_data,
+                                                    frame.encrypted_data_size,
+                                                    frame.plain_text,
+                                                    frame.plain_text_size,
+                                                    frame.key_id,
+                                                    frame.key_id_size));
+}
+
+TEST_F(HmacAesDecryptorTest, MultipleKeysAndFrames) {
+  const WebmEncryptedData& frame = kEncryptedFrames[0];
+  decryptor_.AddKey(frame.key_id, frame.key_id_size,
+                    frame.key, frame.key_size);
+  const WebmEncryptedData& frame2 = kEncryptedFrames[2];
+  decryptor_.AddKey(frame2.key_id, frame2.key_id_size,
+                    frame2.key, frame2.key_size);
+  ASSERT_NO_FATAL_FAILURE(DecryptAndExpectToSucceed(frame.encrypted_data,
+                                                    frame.encrypted_data_size,
+                                                    frame.plain_text,
+                                                    frame.plain_text_size,
+                                                    frame.key_id,
+                                                    frame.key_id_size));
+  ASSERT_NO_FATAL_FAILURE(DecryptAndExpectToSucceed(frame2.encrypted_data,
+                                                    frame2.encrypted_data_size,
+                                                    frame2.plain_text,
+                                                    frame2.plain_text_size,
+                                                    frame2.key_id,
+                                                    frame2.key_id_size));
+}
+
+TEST_F(HmacAesDecryptorTest, HmacCheckFailure) {
+  const WebmEncryptedData& frame = kEncryptedFrames[0];
+  decryptor_.AddKey(frame.key_id, frame.key_id_size,
+                    frame.key, frame.key_size);
+  ASSERT_NO_FATAL_FAILURE(DecryptAndExpectToFail(kFrame0InvalidHmac,
+                                                 frame.encrypted_data_size,
+                                                 frame.plain_text,
+                                                 frame.plain_text_size,
+                                                 frame.key_id,
+                                                 frame.key_id_size));
+}
+
+TEST_F(HmacAesDecryptorTest, IvCheckFailure) {
+  const WebmEncryptedData& frame = kEncryptedFrames[0];
+  decryptor_.AddKey(frame.key_id, frame.key_id_size,
+                    frame.key, frame.key_size);
+  ASSERT_NO_FATAL_FAILURE(DecryptAndExpectToFail(kFrame0InvalidIv,
+                                                 frame.encrypted_data_size,
+                                                 frame.plain_text,
+                                                 frame.plain_text_size,
+                                                 frame.key_id,
+                                                 frame.key_id_size));
+}
+
+TEST_F(HmacAesDecryptorTest, DataCheckFailure) {
+  const WebmEncryptedData& frame = kEncryptedFrames[0];
+  decryptor_.AddKey(frame.key_id, frame.key_id_size,
+                    frame.key, frame.key_size);
+  ASSERT_NO_FATAL_FAILURE(DecryptAndExpectToFail(kFrame0InvalidData,
+                                                 frame.encrypted_data_size,
+                                                 frame.plain_text,
+                                                 frame.plain_text_size,
+                                                 frame.key_id,
+                                                 frame.key_id_size));
 }
 
 }  // media