path: root/dom/media/gmp/widevine-adapter/WidevineDecryptor.cpp

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "WidevineDecryptor.h"

#include "WidevineAdapter.h"
#include "WidevineUtils.h"
#include "WidevineFileIO.h"
#include <mozilla/SizePrintfMacros.h>
#include <stdarg.h>
#include "base/time.h"

using namespace cdm;
using namespace std;

namespace mozilla {

static map<uint32_t, RefPtr<CDMWrapper>> sDecryptors;

/* static */
RefPtr<CDMWrapper>
WidevineDecryptor::GetInstance(uint32_t aInstanceId)
{
  auto itr = sDecryptors.find(aInstanceId);
  if (itr != sDecryptors.end()) {
    return itr->second;
  }
  return nullptr;
}


WidevineDecryptor::WidevineDecryptor()
  : mCallback(nullptr)
{
  Log("WidevineDecryptor created this=%p", this);
  AddRef(); // Released in DecryptingComplete().
}

WidevineDecryptor::~WidevineDecryptor()
{
  Log("WidevineDecryptor destroyed this=%p", this);
}

void
WidevineDecryptor::SetCDM(RefPtr<CDMWrapper> aCDM, uint32_t aInstanceId)
{
  mCDM = aCDM;
  mInstanceId = aInstanceId;
  sDecryptors[mInstanceId] = aCDM;
}

void
WidevineDecryptor::Init(GMPDecryptorCallback* aCallback,
                        bool aDistinctiveIdentifierRequired,
                        bool aPersistentStateRequired)
{
  Log("WidevineDecryptor::Init() this=%p distinctiveId=%d persistentState=%d",
      this, aDistinctiveIdentifierRequired, aPersistentStateRequired);
  MOZ_ASSERT(aCallback);
  mCallback = aCallback;
  MOZ_ASSERT(mCDM);
  mDistinctiveIdentifierRequired = aDistinctiveIdentifierRequired;
  mPersistentStateRequired = aPersistentStateRequired;
  if (CDM()) {
    CDM()->Initialize(aDistinctiveIdentifierRequired,
                      aPersistentStateRequired);
  }
}

static SessionType
ToCDMSessionType(GMPSessionType aSessionType)
{
  switch (aSessionType) {
    case kGMPTemporySession: return kTemporary;
    case kGMPPersistentSession: return kPersistentLicense;
    case kGMPSessionInvalid: return kTemporary;
    // TODO: kPersistentKeyRelease
  }
  MOZ_ASSERT(false); // Not supposed to get here.
  return kTemporary;
}

void
WidevineDecryptor::CreateSession(uint32_t aCreateSessionToken,
                                 uint32_t aPromiseId,
                                 const char* aInitDataType,
                                 uint32_t aInitDataTypeSize,
                                 const uint8_t* aInitData,
                                 uint32_t aInitDataSize,
                                 GMPSessionType aSessionType)
{
  Log("Decryptor::CreateSession(token=%d, pid=%d)", aCreateSessionToken, aPromiseId);
  InitDataType initDataType;
  if (!strcmp(aInitDataType, "cenc")) {
    initDataType = kCenc;
  } else if (!strcmp(aInitDataType, "webm")) {
    initDataType = kWebM;
  } else if (!strcmp(aInitDataType, "keyids")) {
    initDataType = kKeyIds;
  } else {
    // Invalid init data type
    const char* errorMsg = "Invalid init data type when creating session.";
    OnRejectPromise(aPromiseId, kNotSupportedError, 0, errorMsg, sizeof(errorMsg));
    return;
  }
  mPromiseIdToNewSessionTokens[aPromiseId] = aCreateSessionToken;
  CDM()->CreateSessionAndGenerateRequest(aPromiseId,
                                         ToCDMSessionType(aSessionType),
                                         initDataType,
                                         aInitData, aInitDataSize);
}

void
WidevineDecryptor::LoadSession(uint32_t aPromiseId,
                               const char* aSessionId,
                               uint32_t aSessionIdLength)
{
  Log("Decryptor::LoadSession(pid=%d, %s)", aPromiseId, aSessionId);
  // TODO: session type??
  CDM()->LoadSession(aPromiseId, kPersistentLicense, aSessionId, aSessionIdLength);
}

void
WidevineDecryptor::UpdateSession(uint32_t aPromiseId,
                                 const char* aSessionId,
                                 uint32_t aSessionIdLength,
                                 const uint8_t* aResponse,
                                 uint32_t aResponseSize)
{
  Log("Decryptor::UpdateSession(pid=%d, session=%s)", aPromiseId, aSessionId);
  CDM()->UpdateSession(aPromiseId, aSessionId, aSessionIdLength, aResponse, aResponseSize);
}

void
WidevineDecryptor::CloseSession(uint32_t aPromiseId,
                                const char* aSessionId,
                                uint32_t aSessionIdLength)
{
  Log("Decryptor::CloseSession(pid=%d, session=%s)", aPromiseId, aSessionId);
  CDM()->CloseSession(aPromiseId, aSessionId, aSessionIdLength);
}

void
WidevineDecryptor::RemoveSession(uint32_t aPromiseId,
                                 const char* aSessionId,
                                 uint32_t aSessionIdLength)
{
  Log("Decryptor::RemoveSession(%s)", aSessionId);
  CDM()->RemoveSession(aPromiseId, aSessionId, aSessionIdLength);
}

void
WidevineDecryptor::SetServerCertificate(uint32_t aPromiseId,
                                        const uint8_t* aServerCert,
                                        uint32_t aServerCertSize)
{
  Log("Decryptor::SetServerCertificate()");
  CDM()->SetServerCertificate(aPromiseId, aServerCert, aServerCertSize);
}

class WidevineDecryptedBlock : public cdm::DecryptedBlock {
public:

  WidevineDecryptedBlock()
    : mBuffer(nullptr)
    , mTimestamp(0)
  {
  }

  ~WidevineDecryptedBlock() {
    if (mBuffer) {
      mBuffer->Destroy();
      mBuffer = nullptr;
    }
  }

  void SetDecryptedBuffer(cdm::Buffer* aBuffer) override {
    mBuffer = aBuffer;
  }

  cdm::Buffer* DecryptedBuffer() override {
    return mBuffer;
  }

  void SetTimestamp(int64_t aTimestamp) override {
    mTimestamp = aTimestamp;
  }

  int64_t Timestamp() const override {
    return mTimestamp;
  }

private:
  cdm::Buffer* mBuffer;
  int64_t mTimestamp;
};

void
WidevineDecryptor::Decrypt(GMPBuffer* aBuffer,
                           GMPEncryptedBufferMetadata* aMetadata)
{
  if (!mCallback) {
    Log("WidevineDecryptor::Decrypt() this=%p FAIL; !mCallback", this);
    return;
  }
  const GMPEncryptedBufferMetadata* crypto = aMetadata;
  InputBuffer sample;
  nsTArray<SubsampleEntry> subsamples;
  InitInputBuffer(crypto, aBuffer->Id(), aBuffer->Data(), aBuffer->Size(), sample, subsamples);
  WidevineDecryptedBlock decrypted;
  Status rv = CDM()->Decrypt(sample, &decrypted);
  Log("Decryptor::Decrypt(timestamp=%lld) rv=%d sz=%d",
      sample.timestamp, rv, decrypted.DecryptedBuffer()->Size());
  if (rv == kSuccess) {
    aBuffer->Resize(decrypted.DecryptedBuffer()->Size());
    memcpy(aBuffer->Data(),
           decrypted.DecryptedBuffer()->Data(),
           decrypted.DecryptedBuffer()->Size());
  }
  mCallback->Decrypted(aBuffer, ToGMPErr(rv));
}

void
WidevineDecryptor::DecryptingComplete()
{
  Log("WidevineDecryptor::DecryptingComplete() this=%p", this);
  // Drop our references to the CDMWrapper. When any other references
  // held elsewhere are dropped (for example references held by a
  // WidevineVideoDecoder, or a runnable), the CDMWrapper destroys
  // the CDM.
  mCDM = nullptr;
  sDecryptors.erase(mInstanceId);
  mCallback = nullptr;
  Release();
}

class WidevineBuffer : public cdm::Buffer {
public:
  explicit WidevineBuffer(size_t aSize) {
    Log("WidevineBuffer(size=" PRIuSIZE ") created", aSize);
    mBuffer.SetLength(aSize);
  }
  ~WidevineBuffer() {
    Log("WidevineBuffer(size=" PRIuSIZE ") destroyed", Size());
  }
  void Destroy() override { delete this; }
  uint32_t Capacity() const override { return mBuffer.Length(); };
  uint8_t* Data() override { return mBuffer.Elements(); }
  void SetSize(uint32_t aSize) override { mBuffer.SetLength(aSize); }
  uint32_t Size() const override { return mBuffer.Length(); }

private:
  WidevineBuffer(const WidevineBuffer&);
  void operator=(const WidevineBuffer&);

  nsTArray<uint8_t> mBuffer;
};

Buffer*
WidevineDecryptor::Allocate(uint32_t aCapacity)
{
  Log("Decryptor::Allocate(capacity=%u)", aCapacity);
  return new WidevineBuffer(aCapacity);
}

class TimerTask : public GMPTask {
public:
  TimerTask(WidevineDecryptor* aDecryptor,
            RefPtr<CDMWrapper> aCDM,
            void* aContext)
    : mDecryptor(aDecryptor)
    , mCDM(aCDM)
    , mContext(aContext)
  {
  }
  ~TimerTask() override {}
  void Run() override {
    mCDM->GetCDM()->TimerExpired(mContext);
  }
  void Destroy() override { delete this; }
private:
  RefPtr<WidevineDecryptor> mDecryptor;
  RefPtr<CDMWrapper> mCDM;
  void* mContext;
};

void
WidevineDecryptor::SetTimer(int64_t aDelayMs, void* aContext)
{
  Log("Decryptor::SetTimer(delay_ms=%lld, context=0x%x)", aDelayMs, aContext);
  if (mCDM) {
    GMPSetTimerOnMainThread(new TimerTask(this, mCDM, aContext), aDelayMs);
  }
}

Time
WidevineDecryptor::GetCurrentWallTime()
{
  return base::Time::Now().ToDoubleT();
}

void
ChromiumCDMChild::OnResolveKeyStatusPromise(uint32_t aPromiseId,
                                            cdm::KeyStatus aKeyStatus) {
  //TODO: The callback of GetStatusForPolicy. See Mozilla bug 1404230.
}

void
WidevineDecryptor::OnResolveNewSessionPromise(uint32_t aPromiseId,
                                              const char* aSessionId,
                                              uint32_t aSessionIdSize)
{
  if (!mCallback) {
    Log("Decryptor::OnResolveNewSessionPromise(aPromiseId=0x%d) FAIL; !mCallback", aPromiseId);
    return;
  }
  Log("Decryptor::OnResolveNewSessionPromise(aPromiseId=0x%d)", aPromiseId);
  auto iter = mPromiseIdToNewSessionTokens.find(aPromiseId);
  if (iter == mPromiseIdToNewSessionTokens.end()) {
    Log("FAIL: Decryptor::OnResolveNewSessionPromise(aPromiseId=%d) unknown aPromiseId", aPromiseId);
    return;
  }
  mCallback->SetSessionId(iter->second, aSessionId, aSessionIdSize);
  mCallback->ResolvePromise(aPromiseId);
  mPromiseIdToNewSessionTokens.erase(iter);
}

void
WidevineDecryptor::OnResolvePromise(uint32_t aPromiseId)
{
  if (!mCallback) {
    Log("Decryptor::OnResolvePromise(aPromiseId=0x%d) FAIL; !mCallback", aPromiseId);
    return;
  }
  Log("Decryptor::OnResolvePromise(aPromiseId=%d)", aPromiseId);
  mCallback->ResolvePromise(aPromiseId);
}

// Align with spec, the Exceptions used by CDM to reject promises .
// https://w3c.github.io/encrypted-media/#exceptions
cdm::Exception
ConvertCDMErrorToCDMException(cdm::Error error) {
  switch (error) {
    case cdm::kNotSupportedError:
      return cdm::Exception::kExceptionNotSupportedError;
    case cdm::kInvalidStateError:
      return cdm::Exception::kExceptionInvalidStateError;
    case cdm::kInvalidAccessError:
      return cdm::Exception::kExceptionTypeError;
    case cdm::kQuotaExceededError:
      return cdm::Exception::kExceptionQuotaExceededError;
      break;
  }

  return cdm::Exception::kExceptionInvalidStateError;
}

void
WidevineDecryptor::OnRejectPromise(uint32_t aPromiseId,
                                  cdm::Exception aException,
                                  uint32_t aSystemCode,
                                  const char* aErrorMessage,
                                  uint32_t aErrorMessageSize)
{
  if (!mCallback) {
    Log("Decryptor::OnRejectPromise(aPromiseId=%d, err=%d, sysCode=%u, msg=%s) FAIL; !mCallback",
        aPromiseId, (int)aException, aSystemCode, aErrorMessage);
    return;
  }
  Log("Decryptor::OnRejectPromise(aPromiseId=%d, err=%d, sysCode=%u, msg=%s)",
      aPromiseId, (int)aError, aSystemCode, aErrorMessage);
  mCallback->RejectPromise(aPromiseId,
                           ToGMPDOMException(aException),
                           !aErrorMessageSize ? "" : aErrorMessage,
                           aErrorMessageSize);
}

static GMPSessionMessageType
ToGMPMessageType(MessageType message_type)
{
  switch (message_type) {
    case kLicenseRequest: return kGMPLicenseRequest;
    case kLicenseRenewal: return kGMPLicenseRenewal;
    case kLicenseRelease: return kGMPLicenseRelease;
  }
  return kGMPMessageInvalid;
}

void
WidevineDecryptor::OnSessionMessage(const char* aSessionId,
                                   uint32_t aSessionIdSize,
                                   cdm::MessageType aMessageType,
                                   const char* aMessage,
                                   uint32_t aMessageSize)
{
  if (!mCallback) {
    Log("Decryptor::OnSessionMessage() FAIL; !mCallback");
    return;
  }
  Log("Decryptor::OnSessionMessage()");
  mCallback->SessionMessage(aSessionId,
                            aSessionIdSize,
                            ToGMPMessageType(aMessageType),
                            reinterpret_cast<const uint8_t*>(aMessage),
                            aMessageSize);
}

static GMPMediaKeyStatus
ToGMPKeyStatus(KeyStatus aStatus)
{
  switch (aStatus) {
    case kUsable: return kGMPUsable;
    case kInternalError: return kGMPInternalError;
    case kExpired: return kGMPExpired;
    case kOutputRestricted: return kGMPOutputRestricted;
    case kOutputDownscaled: return kGMPOutputDownscaled;
    case kStatusPending: return kGMPStatusPending;
    case kReleased: return kGMPReleased;
  }
  return kGMPUnknown;
}

void
WidevineDecryptor::OnSessionKeysChange(const char* aSessionId,
                                       uint32_t aSessionIdSize,
                                       bool aHasAdditionalUsableKey,
                                       const KeyInformation* aKeysInfo,
                                       uint32_t aKeysInfoCount)
{
  if (!mCallback) {
    Log("Decryptor::OnSessionKeysChange() FAIL; !mCallback");
    return;
  }
  Log("Decryptor::OnSessionKeysChange()");

  nsTArray<GMPMediaKeyInfo> key_infos;
  for (uint32_t i = 0; i < aKeysInfoCount; i++) {
    key_infos.AppendElement(GMPMediaKeyInfo(aKeysInfo[i].key_id,
                                            aKeysInfo[i].key_id_size,
                                            ToGMPKeyStatus(aKeysInfo[i].status)));
  }
  mCallback->BatchedKeyStatusChanged(aSessionId, aSessionIdSize,
                                     key_infos.Elements(), key_infos.Length());
}

static GMPTimestamp
ToGMPTime(Time aCDMTime)
{
  return static_cast<GMPTimestamp>(aCDMTime * 1000);
}

void
WidevineDecryptor::OnExpirationChange(const char* aSessionId,
                                      uint32_t aSessionIdSize,
                                      Time aNewExpiryTime)
{
  if (!mCallback) {
    Log("Decryptor::OnExpirationChange(sid=%s) t=%lf FAIL; !mCallback",
        aSessionId, aNewExpiryTime);
    return;
  }
  Log("Decryptor::OnExpirationChange(sid=%s) t=%lf", aSessionId, aNewExpiryTime);
  GMPTimestamp expiry = ToGMPTime(aNewExpiryTime);
  if (aNewExpiryTime == 0) {
    return;
  }
  mCallback->ExpirationChange(aSessionId, aSessionIdSize, expiry);
}

void
WidevineDecryptor::OnSessionClosed(const char* aSessionId,
                                   uint32_t aSessionIdSize)
{
  if (!mCallback) {
    Log("Decryptor::OnSessionClosed(sid=%s) FAIL; !mCallback", aSessionId);
    return;
  }
  Log("Decryptor::OnSessionClosed(sid=%s)", aSessionId);
  mCallback->SessionClosed(aSessionId, aSessionIdSize);
}

void
WidevineDecryptor::OnLegacySessionError(const char* aSessionId,
                                        uint32_t aSessionIdLength,
                                        Error aError,
                                        uint32_t aSystemCode,
                                        const char* aErrorMessage,
                                        uint32_t aErrorMessageLength)
{
  if (!mCallback) {
    Log("Decryptor::OnLegacySessionError(sid=%s, error=%d) FAIL; !mCallback",
        aSessionId, (int)aError);
    return;
  }
  Log("Decryptor::OnLegacySessionError(sid=%s, error=%d)", aSessionId, (int)aError);
  mCallback->SessionError(aSessionId,
                          aSessionIdLength,
                          ToGMPDOMException(aError),
                          aSystemCode,
                          aErrorMessage,
                          aErrorMessageLength);
}

void
WidevineDecryptor::SendPlatformChallenge(const char* aServiceId,
                                         uint32_t aServiceIdSize,
                                         const char* aChallenge,
                                         uint32_t aChallengeSize)
{
  Log("Decryptor::SendPlatformChallenge(service_id=%s)", aServiceId);
}

void
WidevineDecryptor::EnableOutputProtection(uint32_t aDesiredProtectionMask)
{
  Log("Decryptor::EnableOutputProtection(mask=0x%x)", aDesiredProtectionMask);
}

void
WidevineDecryptor::QueryOutputProtectionStatus()
{
  Log("Decryptor::QueryOutputProtectionStatus()");
}

void
WidevineDecryptor::OnDeferredInitializationDone(StreamType aStreamType,
                                                Status aDecoderStatus)
{
  Log("Decryptor::OnDeferredInitializationDone()");
}

FileIO*
WidevineDecryptor::CreateFileIO(FileIOClient* aClient)
{
  Log("Decryptor::CreateFileIO()");
  if (!mPersistentStateRequired) {
    return nullptr;
  }
  return new WidevineFileIO(aClient);
}

} // namespace mozilla