diff -r 000000000000 -r 6474c204b198 netwerk/protocol/http/Http2Compression.h --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/netwerk/protocol/http/Http2Compression.h Wed Dec 31 06:09:35 2014 +0100 @@ -0,0 +1,198 @@ +/* -*- 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/. */ + +#ifndef mozilla_net_Http2Compression_Internal_h +#define mozilla_net_Http2Compression_Internal_h + +// HPACK +// tools.ietf.org/html/draft-ietf-httpbis-header-compression-04 + +#include "mozilla/Attributes.h" +#include "nsDeque.h" +#include "nsString.h" + +namespace mozilla { +namespace net { + +struct HuffmanIncomingTable; + +void Http2CompressionCleanup(); + +class nvPair +{ +public: +nvPair(const nsACString &name, const nsACString &value) + : mName(name) + , mValue(value) + { } + + uint32_t Size() const { return mName.Length() + mValue.Length() + 32; } + + nsCString mName; + nsCString mValue; +}; + +class nvFIFO +{ +public: + nvFIFO(); + ~nvFIFO(); + void AddElement(const nsCString &name, const nsCString &value); + void AddElement(const nsCString &name); + void RemoveElement(); + uint32_t ByteCount() const; + uint32_t Length() const; + uint32_t VariableLength() const; + void Clear(); + const nvPair *operator[] (int32_t index) const; + +private: + uint32_t mByteCount; + nsDeque mTable; +}; + +class Http2BaseCompressor +{ +public: + Http2BaseCompressor(); + virtual ~Http2BaseCompressor() { }; + +protected: + // this will become a HTTP/2 SETTINGS value in a future draft + const static uint32_t kDefaultMaxBuffer = 4096; + + virtual void ClearHeaderTable(); + virtual void UpdateReferenceSet(int32_t delta); + virtual void IncrementReferenceSetIndices(); + virtual void MakeRoom(uint32_t amount) = 0; + + nsAutoTArray mReferenceSet; // list of indicies + + // the alternate set is used to track the emitted headers when + // processing input for a header set. The input to the compressor + // is a series of nvpairs, the input to the decompressor is the + // series of op codes that make up the header block. + // + // after processing the input the compressor compares the alternate + // set to the inherited reference set and generates indicies to + // toggle off any members of alternate - inherited. the alternate + // then becomes the inherited set for the next header set. + // + // after processing the input the decompressor comapres the alternate + // set to the inherited reference set and generates headers for + // anything implicit in reference - alternate. + nsAutoTArray mAlternateReferenceSet; // list of indicies + + nsACString *mOutput; + nvFIFO mHeaderTable; + + uint32_t mMaxBuffer; +}; + +class Http2Compressor; + +class Http2Decompressor MOZ_FINAL : public Http2BaseCompressor +{ +public: + Http2Decompressor() { }; + virtual ~Http2Decompressor() { } ; + + // NS_OK: Produces the working set of HTTP/1 formatted headers + nsresult DecodeHeaderBlock(const uint8_t *data, uint32_t datalen, + nsACString &output); + + void GetStatus(nsACString &hdr) { hdr = mHeaderStatus; } + void GetHost(nsACString &hdr) { hdr = mHeaderHost; } + void GetScheme(nsACString &hdr) { hdr = mHeaderScheme; } + void GetPath(nsACString &hdr) { hdr = mHeaderPath; } + void GetMethod(nsACString &hdr) { hdr = mHeaderMethod; } + void SetCompressor(Http2Compressor *compressor) { mCompressor = compressor; } + +protected: + virtual void MakeRoom(uint32_t amount) MOZ_OVERRIDE; + +private: + nsresult DoIndexed(); + nsresult DoLiteralWithoutIndex(); + nsresult DoLiteralWithIncremental(); + nsresult DoLiteralInternal(nsACString &, nsACString &); + + nsresult DecodeInteger(uint32_t prefixLen, uint32_t &result); + nsresult OutputHeader(uint32_t index); + nsresult OutputHeader(const nsACString &name, const nsACString &value); + + nsresult CopyHeaderString(uint32_t index, nsACString &name); + nsresult CopyStringFromInput(uint32_t index, nsACString &val); + uint8_t ExtractByte(uint8_t bitsLeft, uint32_t &bytesConsumed); + nsresult CopyHuffmanStringFromInput(uint32_t index, nsACString &val); + nsresult DecodeHuffmanCharacter(HuffmanIncomingTable *table, uint8_t &c, + uint32_t &bytesConsumed, uint8_t &bitsLeft); + nsresult DecodeFinalHuffmanCharacter(HuffmanIncomingTable *table, uint8_t &c, + uint8_t &bitsLeft); + + Http2Compressor *mCompressor; + + nsCString mHeaderStatus; + nsCString mHeaderHost; + nsCString mHeaderScheme; + nsCString mHeaderPath; + nsCString mHeaderMethod; + + // state variables when DecodeBlock() is on the stack + uint32_t mOffset; + const uint8_t *mData; + uint32_t mDataLen; +}; + + +class Http2Compressor MOZ_FINAL : public Http2BaseCompressor +{ +public: + Http2Compressor() : mParsedContentLength(-1) { }; + virtual ~Http2Compressor() { } + + // HTTP/1 formatted header block as input - HTTP/2 formatted + // header block as output + nsresult EncodeHeaderBlock(const nsCString &nvInput, + const nsACString &method, const nsACString &path, + const nsACString &host, const nsACString &scheme, + nsACString &output); + + int64_t GetParsedContentLength() { return mParsedContentLength; } // -1 on not found + + void SetMaxBufferSize(uint32_t maxBufferSize); + nsresult SetMaxBufferSizeInternal(uint32_t maxBufferSize); + +protected: + virtual void ClearHeaderTable() MOZ_OVERRIDE; + virtual void UpdateReferenceSet(int32_t delta) MOZ_OVERRIDE; + virtual void IncrementReferenceSetIndices() MOZ_OVERRIDE; + virtual void MakeRoom(uint32_t amount) MOZ_OVERRIDE; + +private: + enum outputCode { + kPlainLiteral, + kIndexedLiteral, + kToggleOff, + kToggleOn, + kNop + }; + + void DoOutput(Http2Compressor::outputCode code, + const class nvPair *pair, uint32_t index); + void EncodeInteger(uint32_t prefixLen, uint32_t val); + void ProcessHeader(const nvPair inputPair); + void HuffmanAppend(const nsCString &value); + + int64_t mParsedContentLength; + uint32_t mMaxBufferSetting; + + nsAutoTArray mImpliedReferenceSet; +}; + +} // namespace mozilla::net +} // namespace mozilla + +#endif // mozilla_net_Http2Compression_Internal_h