xref: /external/chromium_org/media/base/android/media_drm_bridge.cc

// Copyright (c) 2013 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 "media/base/android/media_drm_bridge.h"

#include "base/android/build_info.h"
#include "base/android/jni_array.h"
#include "base/android/jni_string.h"
#include "base/callback_helpers.h"
#include "base/location.h"
#include "base/logging.h"
#include "base/message_loop/message_loop_proxy.h"
#include "jni/MediaDrmBridge_jni.h"
#include "media/base/android/media_player_manager.h"

using base::android::AttachCurrentThread;
using base::android::ConvertUTF8ToJavaString;
using base::android::ConvertJavaStringToUTF8;
using base::android::JavaByteArrayToByteVector;
using base::android::ScopedJavaLocalRef;

namespace media {

static uint32 ReadUint32(const uint8_t* data) {
  uint32 value = 0;
  for (int i = 0; i < 4; ++i)
    value = (value << 8) | data[i];
  return value;
}

static uint64 ReadUint64(const uint8_t* data) {
  uint64 value = 0;
  for (int i = 0; i < 8; ++i)
    value = (value << 8) | data[i];
  return value;
}

// The structure of an ISO CENC Protection System Specific Header (PSSH) box is
// as follows. (See ISO/IEC FDIS 23001-7:2011(E).)
// Note: ISO boxes use big-endian values.
//
// PSSH {
//   uint32 Size
//   uint32 Type
//   uint64 LargeSize  # Field is only present if value(Size) == 1.
//   uint32 VersionAndFlags
//   uint8[16] SystemId
//   uint32 DataSize
//   uint8[DataSize] Data
// }
static const int kBoxHeaderSize = 8;  // Box's header contains Size and Type.
static const int kBoxLargeSizeSize = 8;
static const int kPsshVersionFlagSize = 4;
static const int kPsshSystemIdSize = 16;
static const int kPsshDataSizeSize = 4;
static const uint32 kTencType = 0x74656e63;
static const uint32 kPsshType = 0x70737368;

// Tries to find a PSSH box whose "SystemId" is |uuid| in |data|, parses the
// "Data" of the box and put it in |pssh_data|. Returns true if such a box is
// found and successfully parsed. Returns false otherwise.
// Notes:
// 1, If multiple PSSH boxes are found,the "Data" of the first matching PSSH box
// will be set in |pssh_data|.
// 2, Only PSSH and TENC boxes are allowed in |data|. TENC boxes are skipped.
static bool GetPsshData(const uint8* data, int data_size,
                        const std::vector<uint8>& uuid,
                        std::vector<uint8>* pssh_data) {
  const uint8* cur = data;
  const uint8* data_end = data + data_size;
  int bytes_left = data_size;

  while (bytes_left > 0) {
    const uint8* box_head = cur;

    if (bytes_left < kBoxHeaderSize)
      return false;

    uint64_t box_size = ReadUint32(cur);
    uint32 type = ReadUint32(cur + 4);
    cur += kBoxHeaderSize;
    bytes_left -= kBoxHeaderSize;

    if (box_size == 1) {  // LargeSize is present.
      if (bytes_left < kBoxLargeSizeSize)
        return false;

      box_size = ReadUint64(cur);
      cur += kBoxLargeSizeSize;
      bytes_left -= kBoxLargeSizeSize;
    } else if (box_size == 0) {
      box_size = bytes_left + kBoxHeaderSize;
    }

    const uint8* box_end = box_head + box_size;
    if (data_end < box_end)
      return false;

    if (type == kTencType) {
      // Skip 'tenc' box.
      cur = box_end;
      bytes_left = data_end - cur;
      continue;
    } else if (type != kPsshType) {
      return false;
    }

    const int kPsshBoxMinimumSize =
        kPsshVersionFlagSize + kPsshSystemIdSize + kPsshDataSizeSize;
    if (box_end < cur + kPsshBoxMinimumSize)
      return false;

    uint32 version_and_flags = ReadUint32(cur);
    cur += kPsshVersionFlagSize;
    bytes_left -= kPsshVersionFlagSize;
    if (version_and_flags != 0)
      return false;

    DCHECK_GE(bytes_left, kPsshSystemIdSize);
    if (!std::equal(uuid.begin(), uuid.end(), cur)) {
      cur = box_end;
      bytes_left = data_end - cur;
      continue;
    }

    cur += kPsshSystemIdSize;
    bytes_left -= kPsshSystemIdSize;

    uint32 data_size = ReadUint32(cur);
    cur += kPsshDataSizeSize;
    bytes_left -= kPsshDataSizeSize;

    if (box_end < cur + data_size)
      return false;

    pssh_data->assign(cur, cur + data_size);
    return true;
  }

  return false;
}

// static
MediaDrmBridge* MediaDrmBridge::Create(int media_keys_id,
                                       const std::vector<uint8>& scheme_uuid,
                                       MediaPlayerManager* manager) {
  if (!IsAvailable() || scheme_uuid.empty())
    return NULL;

  // TODO(qinmin): check whether the uuid is valid.
  return new MediaDrmBridge(media_keys_id, scheme_uuid, manager);
}

bool MediaDrmBridge::IsAvailable() {
  return base::android::BuildInfo::GetInstance()->sdk_int() >= 18;
}

bool MediaDrmBridge::RegisterMediaDrmBridge(JNIEnv* env) {
  return RegisterNativesImpl(env);
}

MediaDrmBridge::MediaDrmBridge(int media_keys_id,
                               const std::vector<uint8>& scheme_uuid,
                               MediaPlayerManager* manager)
    : media_keys_id_(media_keys_id),
      scheme_uuid_(scheme_uuid),
      manager_(manager) {
  JNIEnv* env = AttachCurrentThread();
  CHECK(env);

  ScopedJavaLocalRef<jbyteArray> j_scheme_uuid =
      base::android::ToJavaByteArray(env, &scheme_uuid[0], scheme_uuid.size());
  j_media_drm_.Reset(Java_MediaDrmBridge_create(
      env, j_scheme_uuid.obj(), reinterpret_cast<intptr_t>(this)));
}

MediaDrmBridge::~MediaDrmBridge() {
  JNIEnv* env = AttachCurrentThread();
  Java_MediaDrmBridge_release(env, j_media_drm_.obj());
}

bool MediaDrmBridge::GenerateKeyRequest(const std::string& type,
                                        const uint8* init_data,
                                        int init_data_length) {
  std::vector<uint8> pssh_data;
  if (!GetPsshData(init_data, init_data_length, scheme_uuid_, &pssh_data))
    return false;

  JNIEnv* env = AttachCurrentThread();
  ScopedJavaLocalRef<jbyteArray> j_pssh_data =
      base::android::ToJavaByteArray(env, &pssh_data[0], pssh_data.size());
  ScopedJavaLocalRef<jstring> j_mime = ConvertUTF8ToJavaString(env, type);
  Java_MediaDrmBridge_generateKeyRequest(
      env, j_media_drm_.obj(), j_pssh_data.obj(), j_mime.obj());
  return true;
}

void MediaDrmBridge::AddKey(const uint8* key, int key_length,
                            const uint8* init_data, int init_data_length,
                            const std::string& session_id) {
  JNIEnv* env = AttachCurrentThread();
  ScopedJavaLocalRef<jbyteArray> j_key_data =
      base::android::ToJavaByteArray(env, key, key_length);
  ScopedJavaLocalRef<jstring> j_session_id =
      ConvertUTF8ToJavaString(env, session_id);
  Java_MediaDrmBridge_addKey(
      env, j_media_drm_.obj(), j_session_id.obj(), j_key_data.obj());
}

void MediaDrmBridge::CancelKeyRequest(const std::string& session_id) {
  JNIEnv* env = AttachCurrentThread();
  ScopedJavaLocalRef<jstring> j_session_id =
      ConvertUTF8ToJavaString(env, session_id);
  Java_MediaDrmBridge_cancelKeyRequest(
      env, j_media_drm_.obj(), j_session_id.obj());
}

void MediaDrmBridge::SetMediaCryptoReadyCB(const base::Closure& closure) {
  if (closure.is_null()) {
    media_crypto_ready_cb_.Reset();
    return;
  }

  DCHECK(media_crypto_ready_cb_.is_null());

  if (!GetMediaCrypto().is_null()) {
    base::MessageLoopProxy::current()->PostTask(FROM_HERE, closure);
    return;
  }

  media_crypto_ready_cb_ = closure;
}

void MediaDrmBridge::OnMediaCryptoReady(JNIEnv* env, jobject) {
  DCHECK(!GetMediaCrypto().is_null());
  if (!media_crypto_ready_cb_.is_null())
    base::ResetAndReturn(&media_crypto_ready_cb_).Run();
}

void MediaDrmBridge::OnKeyMessage(JNIEnv* env,
                                  jobject j_media_drm,
                                  jstring j_session_id,
                                  jbyteArray j_message,
                                  jstring j_destination_url) {
  std::string session_id = ConvertJavaStringToUTF8(env, j_session_id);
  std::vector<uint8> message;
  JavaByteArrayToByteVector(env, j_message, &message);
  std::string destination_url = ConvertJavaStringToUTF8(env, j_destination_url);

  manager_->OnKeyMessage(media_keys_id_, session_id, message, destination_url);
}

void MediaDrmBridge::OnKeyAdded(JNIEnv* env, jobject, jstring j_session_id) {
  std::string session_id = ConvertJavaStringToUTF8(env, j_session_id);
  manager_->OnKeyAdded(media_keys_id_, session_id);
}

void MediaDrmBridge::OnKeyError(JNIEnv* env, jobject, jstring j_session_id) {
  // |j_session_id| can be NULL, in which case we'll return an empty string.
  std::string session_id = ConvertJavaStringToUTF8(env, j_session_id);
  manager_->OnKeyError(media_keys_id_, session_id, MediaKeys::kUnknownError, 0);
}

ScopedJavaLocalRef<jobject> MediaDrmBridge::GetMediaCrypto() {
  JNIEnv* env = AttachCurrentThread();
  return Java_MediaDrmBridge_getMediaCrypto(env, j_media_drm_.obj());
}

MediaDrmBridge::SecurityLevel MediaDrmBridge::GetSecurityLevel() {
  JNIEnv* env = AttachCurrentThread();
  ScopedJavaLocalRef<jstring> j_security_level =
      Java_MediaDrmBridge_getSecurityLevel(env, j_media_drm_.obj());
  std::string security_level =
      ConvertJavaStringToUTF8(env, j_security_level.obj());
  if (0 == security_level.compare("L1"))
    return SECURITY_LEVEL_1;
  if (0 == security_level.compare("L3"))
    return SECURITY_LEVEL_3;
  DCHECK(security_level.empty());
  return SECURITY_LEVEL_NONE;
}

bool MediaDrmBridge::IsProtectedSurfaceRequired() {
  return MediaDrmBridge::SECURITY_LEVEL_1 == GetSecurityLevel();
}

}  // namespace media