diff options
Diffstat (limited to 'parser/htmlparser/nsExpatDriver.h')
| -rw-r--r-- | parser/htmlparser/nsExpatDriver.h | 255 |
1 files changed, 255 insertions, 0 deletions
diff --git a/parser/htmlparser/nsExpatDriver.h b/parser/htmlparser/nsExpatDriver.h new file mode 100644 index 0000000000..78f9caf343 --- /dev/null +++ b/parser/htmlparser/nsExpatDriver.h @@ -0,0 +1,255 @@ +/* -*- 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 NS_EXPAT_DRIVER__ +#define NS_EXPAT_DRIVER__ + +#include "expat_config.h" +#include "expat.h" +#include "nsCOMPtr.h" +#include "nsString.h" +#include "nsIDTD.h" +#include "nsIInputStream.h" +#include "nsIParser.h" +#include "nsCycleCollectionParticipant.h" + +#include "rlbox_expat.h" +#include "nsRLBoxExpatDriver.h" +#include "mozilla/UniquePtr.h" + +class nsIExpatSink; +struct nsCatalogData; +class RLBoxExpatSandboxData; +namespace mozilla { +template <typename, size_t> +class Array; +} + +class nsExpatDriver : public nsIDTD { + virtual ~nsExpatDriver(); + + public: + NS_DECL_CYCLE_COLLECTING_ISUPPORTS_FINAL + NS_DECL_NSIDTD + NS_DECL_CYCLE_COLLECTION_CLASS(nsExpatDriver) + + nsExpatDriver(); + + nsresult Initialize(nsIURI* aURI, nsIContentSink* aSink); + + nsresult ResumeParse(nsScanner& aScanner, bool aIsFinalChunk); + + int HandleExternalEntityRef(const char16_t* aOpenEntityNames, + const char16_t* aBase, const char16_t* aSystemId, + const char16_t* aPublicId); + static void HandleStartElement(rlbox_sandbox_expat& aSandbox, + tainted_expat<void*> aUserData, + tainted_expat<const char16_t*> aName, + tainted_expat<const char16_t**> aAtts); + static void HandleStartElementForSystemPrincipal( + rlbox_sandbox_expat& aSandbox, tainted_expat<void*> aUserData, + tainted_expat<const char16_t*> aName, + tainted_expat<const char16_t**> aAtts); + static void HandleEndElement(rlbox_sandbox_expat& aSandbox, + tainted_expat<void*> aUserData, + tainted_expat<const char16_t*> aName); + static void HandleEndElementForSystemPrincipal( + rlbox_sandbox_expat& aSandbox, tainted_expat<void*> aUserData, + tainted_expat<const char16_t*> aName); + nsresult HandleCharacterData(const char16_t* aCData, const uint32_t aLength); + nsresult HandleComment(const char16_t* aName); + nsresult HandleProcessingInstruction(const char16_t* aTarget, + const char16_t* aData); + nsresult HandleXMLDeclaration(const char16_t* aVersion, + const char16_t* aEncoding, int32_t aStandalone); + nsresult HandleDefault(const char16_t* aData, const uint32_t aLength); + nsresult HandleStartCdataSection(); + nsresult HandleEndCdataSection(); + nsresult HandleStartDoctypeDecl(const char16_t* aDoctypeName, + const char16_t* aSysid, + const char16_t* aPubid, + bool aHasInternalSubset); + nsresult HandleEndDoctypeDecl(); + + private: + // Load up an external stream to get external entity information + nsresult OpenInputStreamFromExternalDTD(const char16_t* aFPIStr, + const char16_t* aURLStr, + nsIURI* aBaseURI, + nsIInputStream** aStream, + nsIURI** aAbsURI); + + enum class ChunkOrBufferIsFinal { + None, + FinalChunk, + FinalChunkAndBuffer, + }; + + /** + * Pass a buffer to Expat. If Expat is blocked aBuffer should be null and + * aLength should be 0. The result of the call will be stored in + * mInternalState. Expat will parse as much of the buffer as it can and store + * the rest in its internal buffer. + * + * @param aBuffer the buffer to pass to Expat. May be null. + * @param aLength the length of the buffer to pass to Expat (in number of + * char16_t's). Must be 0 if aBuffer is null and > 0 if + * aBuffer is not null. + * @param aIsFinal whether this is the last chunk in a row passed to + * ParseChunk, and if so whether it's the last chunk and + * buffer passed to ParseChunk (meaning there will be no more + * calls to ParseChunk for the document being parsed). + * @param aConsumed [out] the number of PRUnichars that Expat consumed. This + * doesn't include the PRUnichars that Expat stored in + * its buffer but didn't parse yet. + * @param aLastLineLength [out] the length of the last line that Expat has + * consumed. This will only be computed if + * aIsFinal is not None or mInternalState is set + * to a failure. + */ + void ParseChunk(const char16_t* aBuffer, uint32_t aLength, + ChunkOrBufferIsFinal aIsFinal, uint32_t* aConsumed, + XML_Size* aLastLineLength); + /** + * Wrapper for ParseBuffer. If the buffer is too large to be copied into the + * sandbox all at once, splits it into chunks and invokes ParseBuffer in a + * loop. + * + * @param aBuffer the buffer to pass to Expat. May be null. + * @param aLength the length of the buffer to pass to Expat (in number of + * char16_t's). Must be 0 if aBuffer is null and > 0 if + * aBuffer is not null. + * @param aIsFinal whether there will definitely not be any more new buffers + * passed in to ParseBuffer + * @param aConsumed [out] the number of PRUnichars that Expat consumed. This + * doesn't include the PRUnichars that Expat stored in + * its buffer but didn't parse yet. + * @param aLastLineLength [out] the length of the last line that Expat has + * consumed. + */ + void ChunkAndParseBuffer(const char16_t* aBuffer, uint32_t aLength, + bool aIsFinal, uint32_t* aPassedToExpat, + uint32_t* aConsumed, XML_Size* aLastLineLength); + + nsresult HandleError(); + + void MaybeStopParser(nsresult aState); + + bool BlockedOrInterrupted() { + return mInternalState == NS_ERROR_HTMLPARSER_BLOCK || + mInternalState == NS_ERROR_HTMLPARSER_INTERRUPTED; + } + + // Expat allows us to set the base URI for entities. It doesn't use the base + // URI itself, but just passes it along to all the entity handlers (just the + // external entity reference handler for us). It does expect the base URI as a + // null-terminated string, with the same character type as the parsed buffers + // (char16_t in our case). Because nsIURI stores a UTF-8 string we have to do + // a conversion to UTF-16 for Expat. We also RLBox the Expat parser, so we + // also do 2 copies (into RLBox sandbox, and Expat does a copy into its pool). + // Most of the time this base URI is unused (the external entity handler is + // rarely called), but when it is we also convert it back to a nsIURI, so we + // convert the string back to UTF-8. + // + // We'd rather not do any of these conversions and copies, so we use a (hacky) + // workaround. We store all base URIs in an array of nsIURIs. Instead of + // passing the real URI to Expat as a string, we pass it a null-terminated + // 2-character buffer. The first character of that buffer stores the index of + // the corresponding nsIURI in the array (incremented with 1 because 0 is used + // to terminate a string). The entity handler can then use the index from the + // base URI that Expat passes it to look up the right nsIURI from the array. + // + // GetExpatBaseURI pushes the nsIURI to the array, and creates the + // two-character buffer for it. + // + // GetBaseURI looks up the right nsIURI in the array, based on the index from + // the two-character buffer. + using ExpatBaseURI = mozilla::Array<XML_Char, 2>; + ExpatBaseURI GetExpatBaseURI(nsIURI* aURI); + nsIURI* GetBaseURI(const XML_Char* aBase) const; + + RLBoxExpatSandboxData* SandboxData() const; + rlbox_sandbox_expat* Sandbox() const; + + // Destroy expat parser and return sandbox to pool + void Destroy(); + + mozilla::UniquePtr<mozilla::RLBoxSandboxPoolData> mSandboxPoolData; + tainted_expat<XML_Parser> mExpatParser; + + nsString mLastLine; + nsString mCDataText; + // Various parts of a doctype + nsString mDoctypeName; + nsString mSystemID; + nsString mPublicID; + nsString mInternalSubset; + bool mInCData; + bool mInInternalSubset; + bool mInExternalDTD; + bool mMadeFinalCallToExpat; + + // Used to track if we're in the parser. + bool mInParser; + + nsresult mInternalState; + + // The length of the data in Expat's buffer (in number of PRUnichars). + uint32_t mExpatBuffered; + + uint16_t mTagDepth; + + // These sinks all refer the same conceptual object. mOriginalSink is + // identical with the nsIContentSink* passed to WillBuildModel, and exists + // only to avoid QI-ing back to nsIContentSink*. + nsCOMPtr<nsIContentSink> mOriginalSink; + nsCOMPtr<nsIExpatSink> mSink; + + const nsCatalogData* mCatalogData; // weak + nsTArray<nsCOMPtr<nsIURI>> mURIs; + + // Used for error reporting. + uint64_t mInnerWindowID; +}; + +class RLBoxExpatSandboxData : public mozilla::RLBoxSandboxDataBase { + friend class RLBoxExpatSandboxPool; + friend class nsExpatDriver; + + public: + explicit RLBoxExpatSandboxData(uint64_t aSize) + : mozilla::RLBoxSandboxDataBase(aSize) { + MOZ_COUNT_CTOR(RLBoxExpatSandboxData); + } + ~RLBoxExpatSandboxData(); + rlbox_sandbox_expat* Sandbox() const { return mSandbox.get(); } + // After getting a sandbox from the pool we need to register the + // Handle{Start,End}Element callbacks and associate the driver with the + // sandbox. + void AttachDriver(bool IsSystemPrincipal, void* aDriver); + void DetachDriver(); + + private: + mozilla::UniquePtr<rlbox_sandbox_expat> mSandbox; + // Common expat callbacks that persist across calls to {Attach,Detach}Driver, + // and consequently across sandbox reuses. + sandbox_callback_expat<XML_XmlDeclHandler> mHandleXMLDeclaration; + sandbox_callback_expat<XML_CharacterDataHandler> mHandleCharacterData; + sandbox_callback_expat<XML_ProcessingInstructionHandler> + mHandleProcessingInstruction; + sandbox_callback_expat<XML_DefaultHandler> mHandleDefault; + sandbox_callback_expat<XML_ExternalEntityRefHandler> mHandleExternalEntityRef; + sandbox_callback_expat<XML_CommentHandler> mHandleComment; + sandbox_callback_expat<XML_StartCdataSectionHandler> mHandleStartCdataSection; + sandbox_callback_expat<XML_EndCdataSectionHandler> mHandleEndCdataSection; + sandbox_callback_expat<XML_StartDoctypeDeclHandler> mHandleStartDoctypeDecl; + sandbox_callback_expat<XML_EndDoctypeDeclHandler> mHandleEndDoctypeDecl; + // Expat callbacks specific to each driver, and thus (re)set across sandbox + // reuses. + sandbox_callback_expat<XML_StartElementHandler> mHandleStartElement; + sandbox_callback_expat<XML_EndElementHandler> mHandleEndElement; +}; + +#endif |