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Diffstat (limited to 'dom/quota/DecryptingInputStream.h')
| -rw-r--r-- | dom/quota/DecryptingInputStream.h | 163 |
1 files changed, 163 insertions, 0 deletions
diff --git a/dom/quota/DecryptingInputStream.h b/dom/quota/DecryptingInputStream.h new file mode 100644 index 0000000000..7559ca860e --- /dev/null +++ b/dom/quota/DecryptingInputStream.h @@ -0,0 +1,163 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* 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/. */ + +#ifndef mozilla_dom_quota_DecryptingInputStream_h +#define mozilla_dom_quota_DecryptingInputStream_h + +// Local includes +#include "EncryptedBlock.h" + +// Global includes +#include <cstddef> +#include <cstdint> +#include "ErrorList.h" +#include "mozilla/InitializedOnce.h" +#include "mozilla/Maybe.h" +#include "mozilla/NotNull.h" +#include "mozilla/ipc/InputStreamParams.h" +#include "nsCOMPtr.h" +#include "nsICloneableInputStream.h" +#include "nsIIPCSerializableInputStream.h" +#include "nsIInputStream.h" +#include "nsISeekableStream.h" +#include "nsISupports.h" +#include "nsITellableStream.h" +#include "nsTArray.h" +#include "nscore.h" + +template <class T> +class nsCOMPtr; + +namespace mozilla::dom::quota { + +class DecryptingInputStreamBase : public nsIInputStream, + public nsISeekableStream, + public nsICloneableInputStream, + public nsIIPCSerializableInputStream { + public: + NS_DECL_THREADSAFE_ISUPPORTS + + NS_IMETHOD Read(char* aBuf, uint32_t aCount, uint32_t* _retval) final; + NS_IMETHOD IsNonBlocking(bool* _retval) final; + + NS_IMETHOD SetEOF() final; + + using nsICloneableInputStream::GetCloneable; + NS_IMETHOD GetCloneable(bool* aCloneable) final; + + void SerializedComplexity(uint32_t aMaxSize, uint32_t* aSizeUsed, + uint32_t* aPipes, + uint32_t* aTransferables) override; + + protected: + DecryptingInputStreamBase(MovingNotNull<nsCOMPtr<nsIInputStream>> aBaseStream, + size_t aBlockSize); + + // For deserialization only. + DecryptingInputStreamBase() = default; + + virtual ~DecryptingInputStreamBase() = default; + + void Init(MovingNotNull<nsCOMPtr<nsIInputStream>> aBaseStream, + size_t aBlockSize); + + // Convenience routine to determine how many bytes of plain data + // we currently have in our buffer. + size_t PlainLength() const; + + size_t EncryptedBufferLength() const; + + LazyInitializedOnceEarlyDestructible<const NotNull<nsCOMPtr<nsIInputStream>>> + mBaseStream; + LazyInitializedOnce<const NotNull<nsISeekableStream*>> mBaseSeekableStream; + LazyInitializedOnce<const NotNull<nsICloneableInputStream*>> + mBaseCloneableInputStream; + LazyInitializedOnce<const NotNull<nsIIPCSerializableInputStream*>> + mBaseIPCSerializableInputStream; + + // Number of bytes of plain data in mBuffer. + size_t mPlainBytes = 0; + + // Next byte of mBuffer to return in ReadSegments(). + size_t mNextByte = 0; + + LazyInitializedOnceNotNull<const size_t> mBlockSize; + + size_t mLastBlockLength = 0; +}; + +// Wraps another nsIInputStream which contains data written using +// EncryptingInputStream with a compatible CipherStategy and key. See the +// remarks on EncryptingOutputStream. +template <typename CipherStrategy> +class DecryptingInputStream final : public DecryptingInputStreamBase { + public: + // Construct a new blocking stream to decrypt the given base stream. The + // base stream must also be blocking. The base stream does not have to be + // buffered. + DecryptingInputStream(MovingNotNull<nsCOMPtr<nsIInputStream>> aBaseStream, + size_t aBlockSize, + typename CipherStrategy::KeyType aKey); + + // For deserialization only. + explicit DecryptingInputStream(); + + NS_IMETHOD Close() override; + NS_IMETHOD Available(uint64_t* _retval) override; + NS_IMETHOD ReadSegments(nsWriteSegmentFun aWriter, void* aClosure, + uint32_t aCount, uint32_t* _retval) override; + + NS_DECL_NSITELLABLESTREAM + + NS_IMETHOD Seek(int32_t aWhence, int64_t aOffset) override; + + NS_IMETHOD Clone(nsIInputStream** _retval) override; + + void Serialize(mozilla::ipc::InputStreamParams& aParams, uint32_t aMaxSize, + uint32_t* aSizeUsed) override; + + bool Deserialize(const mozilla::ipc::InputStreamParams& aParams) override; + + private: + ~DecryptingInputStream(); + + // Parse the next chunk of data. This may populate mBuffer and set + // mBufferFillSize. This should not be called when mBuffer already + // contains data. + nsresult ParseNextChunk(uint32_t* aBytesReadOut); + + // Convenience routine to Read() from the base stream until we get + // the given number of bytes or reach EOF. + // + // aBuf - The buffer to write the bytes into. + // aCount - Max number of bytes to read. If the stream closes + // fewer bytes my be read. + // aMinValidCount - A minimum expected number of bytes. If we find + // fewer than this many bytes, then return + // NS_ERROR_CORRUPTED_CONTENT. If nothing was read due + // due to EOF (aBytesReadOut == 0), then NS_OK is returned. + // aBytesReadOut - An out parameter indicating how many bytes were read. + nsresult ReadAll(char* aBuf, uint32_t aCount, uint32_t aMinValidCount, + uint32_t* aBytesReadOut); + + bool EnsureBuffers(); + + CipherStrategy mCipherStrategy; + LazyInitializedOnce<const typename CipherStrategy::KeyType> mKey; + + // Buffer to hold encrypted data. Must copy here since we need a + // flat buffer to run the decryption process on. + using EncryptedBlockType = EncryptedBlock<CipherStrategy::BlockPrefixLength, + CipherStrategy::BasicBlockSize>; + Maybe<EncryptedBlockType> mEncryptedBlock; + + // Buffer storing the resulting plain data. + nsTArray<uint8_t> mPlainBuffer; +}; + +} // namespace mozilla::dom::quota + +#endif |