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authordsinclair <dsinclair@chromium.org>2016-10-04 11:55:50 -0700
committerCommit bot <commit-bot@chromium.org>2016-10-04 11:55:51 -0700
commit488b7ad845d6de212d89cd957303b294ecfa5922 (patch)
treeadfdd2327724bd3597a1a7614bbe29a01a0c8dc0 /core/fpdfapi/parser/cpdf_parser.cpp
parent41872fa5ac7448a50f66ad56d7bde8d1aa77db4b (diff)
downloadpdfium-488b7ad845d6de212d89cd957303b294ecfa5922.tar.xz
Move core/fpdfapi/fpdf_parser to core/fpdfapi/parser
BUG=pdfium:603 Review-Url: https://codereview.chromium.org/2392603004
Diffstat (limited to 'core/fpdfapi/parser/cpdf_parser.cpp')
-rw-r--r--core/fpdfapi/parser/cpdf_parser.cpp1637
1 files changed, 1637 insertions, 0 deletions
diff --git a/core/fpdfapi/parser/cpdf_parser.cpp b/core/fpdfapi/parser/cpdf_parser.cpp
new file mode 100644
index 0000000000..17539101a1
--- /dev/null
+++ b/core/fpdfapi/parser/cpdf_parser.cpp
@@ -0,0 +1,1637 @@
+// Copyright 2016 PDFium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
+
+#include "core/fpdfapi/parser/cpdf_parser.h"
+
+#include <vector>
+
+#include "core/fpdfapi/parser/cpdf_array.h"
+#include "core/fpdfapi/parser/cpdf_crypto_handler.h"
+#include "core/fpdfapi/parser/cpdf_dictionary.h"
+#include "core/fpdfapi/parser/cpdf_document.h"
+#include "core/fpdfapi/parser/cpdf_number.h"
+#include "core/fpdfapi/parser/cpdf_reference.h"
+#include "core/fpdfapi/parser/cpdf_security_handler.h"
+#include "core/fpdfapi/parser/cpdf_stream.h"
+#include "core/fpdfapi/parser/cpdf_stream_acc.h"
+#include "core/fpdfapi/parser/cpdf_syntax_parser.h"
+#include "core/fpdfapi/parser/fpdf_parser_utility.h"
+#include "core/fxcrt/fx_ext.h"
+#include "core/fxcrt/fx_safe_types.h"
+#include "third_party/base/stl_util.h"
+
+namespace {
+
+// A limit on the size of the xref table. Theoretical limits are higher, but
+// this may be large enough in practice.
+const int32_t kMaxXRefSize = 1048576;
+
+uint32_t GetVarInt(const uint8_t* p, int32_t n) {
+ uint32_t result = 0;
+ for (int32_t i = 0; i < n; ++i)
+ result = result * 256 + p[i];
+ return result;
+}
+
+int32_t GetStreamNCount(CPDF_StreamAcc* pObjStream) {
+ return pObjStream->GetDict()->GetIntegerFor("N");
+}
+
+int32_t GetStreamFirst(CPDF_StreamAcc* pObjStream) {
+ return pObjStream->GetDict()->GetIntegerFor("First");
+}
+
+} // namespace
+
+CPDF_Parser::CPDF_Parser()
+ : m_pDocument(nullptr),
+ m_bHasParsed(false),
+ m_bOwnFileRead(true),
+ m_FileVersion(0),
+ m_pTrailer(nullptr),
+ m_pEncryptDict(nullptr),
+ m_bVersionUpdated(false),
+ m_pLinearized(nullptr),
+ m_dwFirstPageNo(0),
+ m_dwXrefStartObjNum(0) {
+ m_pSyntax.reset(new CPDF_SyntaxParser);
+}
+
+CPDF_Parser::~CPDF_Parser() {
+ if (m_pTrailer)
+ m_pTrailer->Release();
+
+ ReleaseEncryptHandler();
+ SetEncryptDictionary(nullptr);
+
+ if (m_bOwnFileRead && m_pSyntax->m_pFileAccess) {
+ m_pSyntax->m_pFileAccess->Release();
+ m_pSyntax->m_pFileAccess = nullptr;
+ }
+
+ int32_t iLen = m_Trailers.GetSize();
+ for (int32_t i = 0; i < iLen; ++i) {
+ if (CPDF_Dictionary* trailer = m_Trailers.GetAt(i))
+ trailer->Release();
+ }
+
+ if (m_pLinearized)
+ m_pLinearized->Release();
+}
+
+uint32_t CPDF_Parser::GetLastObjNum() const {
+ return m_ObjectInfo.empty() ? 0 : m_ObjectInfo.rbegin()->first;
+}
+
+bool CPDF_Parser::IsValidObjectNumber(uint32_t objnum) const {
+ return !m_ObjectInfo.empty() && objnum <= m_ObjectInfo.rbegin()->first;
+}
+
+FX_FILESIZE CPDF_Parser::GetObjectPositionOrZero(uint32_t objnum) const {
+ auto it = m_ObjectInfo.find(objnum);
+ return it != m_ObjectInfo.end() ? it->second.pos : 0;
+}
+
+uint8_t CPDF_Parser::GetObjectType(uint32_t objnum) const {
+ ASSERT(IsValidObjectNumber(objnum));
+ auto it = m_ObjectInfo.find(objnum);
+ return it != m_ObjectInfo.end() ? it->second.type : 0;
+}
+
+uint16_t CPDF_Parser::GetObjectGenNum(uint32_t objnum) const {
+ ASSERT(IsValidObjectNumber(objnum));
+ auto it = m_ObjectInfo.find(objnum);
+ return it != m_ObjectInfo.end() ? it->second.gennum : 0;
+}
+
+bool CPDF_Parser::IsObjectFreeOrNull(uint32_t objnum) const {
+ uint8_t type = GetObjectType(objnum);
+ return type == 0 || type == 255;
+}
+
+void CPDF_Parser::SetEncryptDictionary(CPDF_Dictionary* pDict) {
+ m_pEncryptDict = pDict;
+}
+
+CPDF_CryptoHandler* CPDF_Parser::GetCryptoHandler() {
+ return m_pSyntax->m_pCryptoHandler.get();
+}
+
+IFX_FileRead* CPDF_Parser::GetFileAccess() const {
+ return m_pSyntax->m_pFileAccess;
+}
+
+void CPDF_Parser::ShrinkObjectMap(uint32_t objnum) {
+ if (objnum == 0) {
+ m_ObjectInfo.clear();
+ return;
+ }
+
+ auto it = m_ObjectInfo.lower_bound(objnum);
+ while (it != m_ObjectInfo.end()) {
+ auto saved_it = it++;
+ m_ObjectInfo.erase(saved_it);
+ }
+
+ if (!pdfium::ContainsKey(m_ObjectInfo, objnum - 1))
+ m_ObjectInfo[objnum - 1].pos = 0;
+}
+
+CPDF_Parser::Error CPDF_Parser::StartParse(IFX_FileRead* pFileAccess,
+ CPDF_Document* pDocument) {
+ ASSERT(!m_bHasParsed);
+ m_bHasParsed = true;
+
+ m_bXRefStream = FALSE;
+ m_LastXRefOffset = 0;
+ m_bOwnFileRead = true;
+
+ int32_t offset = GetHeaderOffset(pFileAccess);
+ if (offset == -1) {
+ if (pFileAccess)
+ pFileAccess->Release();
+ return FORMAT_ERROR;
+ }
+ m_pSyntax->InitParser(pFileAccess, offset);
+
+ uint8_t ch;
+ if (!m_pSyntax->GetCharAt(5, ch))
+ return FORMAT_ERROR;
+ if (std::isdigit(ch))
+ m_FileVersion = FXSYS_toDecimalDigit(static_cast<FX_WCHAR>(ch)) * 10;
+
+ if (!m_pSyntax->GetCharAt(7, ch))
+ return FORMAT_ERROR;
+ if (std::isdigit(ch))
+ m_FileVersion += FXSYS_toDecimalDigit(static_cast<FX_WCHAR>(ch));
+
+ if (m_pSyntax->m_FileLen < m_pSyntax->m_HeaderOffset + 9)
+ return FORMAT_ERROR;
+
+ m_pSyntax->RestorePos(m_pSyntax->m_FileLen - m_pSyntax->m_HeaderOffset - 9);
+ m_pDocument = pDocument;
+
+ FX_BOOL bXRefRebuilt = FALSE;
+ if (m_pSyntax->SearchWord("startxref", TRUE, FALSE, 4096)) {
+ m_SortedOffset.insert(m_pSyntax->SavePos());
+ m_pSyntax->GetKeyword();
+
+ bool bNumber;
+ CFX_ByteString xrefpos_str = m_pSyntax->GetNextWord(&bNumber);
+ if (!bNumber)
+ return FORMAT_ERROR;
+
+ m_LastXRefOffset = (FX_FILESIZE)FXSYS_atoi64(xrefpos_str.c_str());
+ if (!LoadAllCrossRefV4(m_LastXRefOffset) &&
+ !LoadAllCrossRefV5(m_LastXRefOffset)) {
+ if (!RebuildCrossRef())
+ return FORMAT_ERROR;
+
+ bXRefRebuilt = TRUE;
+ m_LastXRefOffset = 0;
+ }
+ } else {
+ if (!RebuildCrossRef())
+ return FORMAT_ERROR;
+
+ bXRefRebuilt = TRUE;
+ }
+ Error eRet = SetEncryptHandler();
+ if (eRet != SUCCESS)
+ return eRet;
+
+ m_pDocument->LoadDoc();
+ if (!m_pDocument->GetRoot() || m_pDocument->GetPageCount() == 0) {
+ if (bXRefRebuilt)
+ return FORMAT_ERROR;
+
+ ReleaseEncryptHandler();
+ if (!RebuildCrossRef())
+ return FORMAT_ERROR;
+
+ eRet = SetEncryptHandler();
+ if (eRet != SUCCESS)
+ return eRet;
+
+ m_pDocument->LoadDoc();
+ if (!m_pDocument->GetRoot())
+ return FORMAT_ERROR;
+ }
+ if (GetRootObjNum() == 0) {
+ ReleaseEncryptHandler();
+ if (!RebuildCrossRef() || GetRootObjNum() == 0)
+ return FORMAT_ERROR;
+
+ eRet = SetEncryptHandler();
+ if (eRet != SUCCESS)
+ return eRet;
+ }
+ if (m_pSecurityHandler && !m_pSecurityHandler->IsMetadataEncrypted()) {
+ CPDF_Reference* pMetadata =
+ ToReference(m_pDocument->GetRoot()->GetObjectFor("Metadata"));
+ if (pMetadata)
+ m_pSyntax->m_MetadataObjnum = pMetadata->GetRefObjNum();
+ }
+ return SUCCESS;
+}
+CPDF_Parser::Error CPDF_Parser::SetEncryptHandler() {
+ ReleaseEncryptHandler();
+ SetEncryptDictionary(nullptr);
+
+ if (!m_pTrailer)
+ return FORMAT_ERROR;
+
+ CPDF_Object* pEncryptObj = m_pTrailer->GetObjectFor("Encrypt");
+ if (pEncryptObj) {
+ if (CPDF_Dictionary* pEncryptDict = pEncryptObj->AsDictionary()) {
+ SetEncryptDictionary(pEncryptDict);
+ } else if (CPDF_Reference* pRef = pEncryptObj->AsReference()) {
+ pEncryptObj = m_pDocument->GetOrParseIndirectObject(pRef->GetRefObjNum());
+ if (pEncryptObj)
+ SetEncryptDictionary(pEncryptObj->GetDict());
+ }
+ }
+
+ if (m_pEncryptDict) {
+ CFX_ByteString filter = m_pEncryptDict->GetStringFor("Filter");
+ std::unique_ptr<CPDF_SecurityHandler> pSecurityHandler;
+ Error err = HANDLER_ERROR;
+ if (filter == "Standard") {
+ pSecurityHandler.reset(new CPDF_SecurityHandler);
+ err = PASSWORD_ERROR;
+ }
+ if (!pSecurityHandler)
+ return HANDLER_ERROR;
+
+ if (!pSecurityHandler->OnInit(this, m_pEncryptDict))
+ return err;
+
+ m_pSecurityHandler = std::move(pSecurityHandler);
+ std::unique_ptr<CPDF_CryptoHandler> pCryptoHandler(
+ m_pSecurityHandler->CreateCryptoHandler());
+ if (!pCryptoHandler->Init(m_pEncryptDict, m_pSecurityHandler.get()))
+ return HANDLER_ERROR;
+ m_pSyntax->SetEncrypt(std::move(pCryptoHandler));
+ }
+ return SUCCESS;
+}
+
+void CPDF_Parser::ReleaseEncryptHandler() {
+ m_pSyntax->m_pCryptoHandler.reset();
+ m_pSecurityHandler.reset();
+}
+
+FX_FILESIZE CPDF_Parser::GetObjectOffset(uint32_t objnum) const {
+ if (!IsValidObjectNumber(objnum))
+ return 0;
+
+ if (GetObjectType(objnum) == 1)
+ return GetObjectPositionOrZero(objnum);
+
+ if (GetObjectType(objnum) == 2) {
+ FX_FILESIZE pos = GetObjectPositionOrZero(objnum);
+ return GetObjectPositionOrZero(pos);
+ }
+ return 0;
+}
+
+// Ideally, all the cross reference entries should be verified.
+// In reality, we rarely see well-formed cross references don't match
+// with the objects. crbug/602650 showed a case where object numbers
+// in the cross reference table are all off by one.
+bool CPDF_Parser::VerifyCrossRefV4() {
+ for (const auto& it : m_ObjectInfo) {
+ if (it.second.pos == 0)
+ continue;
+ // Find the first non-zero position.
+ FX_FILESIZE SavedPos = m_pSyntax->SavePos();
+ m_pSyntax->RestorePos(it.second.pos);
+ bool is_num = false;
+ CFX_ByteString num_str = m_pSyntax->GetNextWord(&is_num);
+ m_pSyntax->RestorePos(SavedPos);
+ if (!is_num || num_str.IsEmpty() ||
+ FXSYS_atoui(num_str.c_str()) != it.first) {
+ // If the object number read doesn't match the one stored,
+ // something is wrong with the cross reference table.
+ return false;
+ } else {
+ return true;
+ }
+ }
+ return true;
+}
+
+FX_BOOL CPDF_Parser::LoadAllCrossRefV4(FX_FILESIZE xrefpos) {
+ if (!LoadCrossRefV4(xrefpos, 0, TRUE))
+ return FALSE;
+
+ m_pTrailer = LoadTrailerV4();
+ if (!m_pTrailer)
+ return FALSE;
+
+ int32_t xrefsize = GetDirectInteger(m_pTrailer, "Size");
+ if (xrefsize > 0 && xrefsize <= kMaxXRefSize)
+ ShrinkObjectMap(xrefsize);
+
+ std::vector<FX_FILESIZE> CrossRefList;
+ std::vector<FX_FILESIZE> XRefStreamList;
+ std::set<FX_FILESIZE> seen_xrefpos;
+
+ CrossRefList.push_back(xrefpos);
+ XRefStreamList.push_back(GetDirectInteger(m_pTrailer, "XRefStm"));
+ seen_xrefpos.insert(xrefpos);
+
+ // When |m_pTrailer| doesn't have Prev entry or Prev entry value is not
+ // numerical, GetDirectInteger() returns 0. Loading will end.
+ xrefpos = GetDirectInteger(m_pTrailer, "Prev");
+ while (xrefpos) {
+ // Check for circular references.
+ if (pdfium::ContainsKey(seen_xrefpos, xrefpos))
+ return FALSE;
+
+ seen_xrefpos.insert(xrefpos);
+
+ // SLOW ...
+ CrossRefList.insert(CrossRefList.begin(), xrefpos);
+ LoadCrossRefV4(xrefpos, 0, TRUE);
+
+ std::unique_ptr<CPDF_Dictionary, ReleaseDeleter<CPDF_Dictionary>> pDict(
+ LoadTrailerV4());
+ if (!pDict)
+ return FALSE;
+
+ xrefpos = GetDirectInteger(pDict.get(), "Prev");
+
+ // SLOW ...
+ XRefStreamList.insert(XRefStreamList.begin(),
+ pDict->GetIntegerFor("XRefStm"));
+ m_Trailers.Add(pDict.release());
+ }
+
+ for (size_t i = 0; i < CrossRefList.size(); ++i) {
+ if (!LoadCrossRefV4(CrossRefList[i], XRefStreamList[i], FALSE))
+ return FALSE;
+ if (i == 0 && !VerifyCrossRefV4())
+ return FALSE;
+ }
+ return TRUE;
+}
+
+FX_BOOL CPDF_Parser::LoadLinearizedAllCrossRefV4(FX_FILESIZE xrefpos,
+ uint32_t dwObjCount) {
+ if (!LoadLinearizedCrossRefV4(xrefpos, dwObjCount))
+ return FALSE;
+
+ m_pTrailer = LoadTrailerV4();
+ if (!m_pTrailer)
+ return FALSE;
+
+ int32_t xrefsize = GetDirectInteger(m_pTrailer, "Size");
+ if (xrefsize == 0)
+ return FALSE;
+
+ std::vector<FX_FILESIZE> CrossRefList;
+ std::vector<FX_FILESIZE> XRefStreamList;
+ std::set<FX_FILESIZE> seen_xrefpos;
+
+ CrossRefList.push_back(xrefpos);
+ XRefStreamList.push_back(GetDirectInteger(m_pTrailer, "XRefStm"));
+ seen_xrefpos.insert(xrefpos);
+
+ xrefpos = GetDirectInteger(m_pTrailer, "Prev");
+ while (xrefpos) {
+ // Check for circular references.
+ if (pdfium::ContainsKey(seen_xrefpos, xrefpos))
+ return FALSE;
+
+ seen_xrefpos.insert(xrefpos);
+
+ // SLOW ...
+ CrossRefList.insert(CrossRefList.begin(), xrefpos);
+ LoadCrossRefV4(xrefpos, 0, TRUE);
+
+ std::unique_ptr<CPDF_Dictionary, ReleaseDeleter<CPDF_Dictionary>> pDict(
+ LoadTrailerV4());
+ if (!pDict)
+ return FALSE;
+
+ xrefpos = GetDirectInteger(pDict.get(), "Prev");
+
+ // SLOW ...
+ XRefStreamList.insert(XRefStreamList.begin(),
+ pDict->GetIntegerFor("XRefStm"));
+ m_Trailers.Add(pDict.release());
+ }
+
+ for (size_t i = 1; i < CrossRefList.size(); ++i) {
+ if (!LoadCrossRefV4(CrossRefList[i], XRefStreamList[i], FALSE))
+ return FALSE;
+ }
+ return TRUE;
+}
+
+FX_BOOL CPDF_Parser::LoadLinearizedCrossRefV4(FX_FILESIZE pos,
+ uint32_t dwObjCount) {
+ FX_FILESIZE dwStartPos = pos - m_pSyntax->m_HeaderOffset;
+
+ m_pSyntax->RestorePos(dwStartPos);
+ m_SortedOffset.insert(pos);
+
+ uint32_t start_objnum = 0;
+ uint32_t count = dwObjCount;
+ FX_FILESIZE SavedPos = m_pSyntax->SavePos();
+
+ const int32_t recordsize = 20;
+ std::vector<char> buf(1024 * recordsize + 1);
+ buf[1024 * recordsize] = '\0';
+
+ int32_t nBlocks = count / 1024 + 1;
+ for (int32_t block = 0; block < nBlocks; block++) {
+ int32_t block_size = block == nBlocks - 1 ? count % 1024 : 1024;
+ uint32_t dwReadSize = block_size * recordsize;
+ if ((FX_FILESIZE)(dwStartPos + dwReadSize) > m_pSyntax->m_FileLen)
+ return FALSE;
+
+ if (!m_pSyntax->ReadBlock(reinterpret_cast<uint8_t*>(buf.data()),
+ dwReadSize)) {
+ return FALSE;
+ }
+
+ for (int32_t i = 0; i < block_size; i++) {
+ uint32_t objnum = start_objnum + block * 1024 + i;
+ char* pEntry = &buf[i * recordsize];
+ if (pEntry[17] == 'f') {
+ m_ObjectInfo[objnum].pos = 0;
+ m_ObjectInfo[objnum].type = 0;
+ } else {
+ int32_t offset = FXSYS_atoi(pEntry);
+ if (offset == 0) {
+ for (int32_t c = 0; c < 10; c++) {
+ if (!std::isdigit(pEntry[c]))
+ return FALSE;
+ }
+ }
+
+ m_ObjectInfo[objnum].pos = offset;
+ int32_t version = FXSYS_atoi(pEntry + 11);
+ if (version >= 1)
+ m_bVersionUpdated = true;
+
+ m_ObjectInfo[objnum].gennum = version;
+ if (m_ObjectInfo[objnum].pos < m_pSyntax->m_FileLen)
+ m_SortedOffset.insert(m_ObjectInfo[objnum].pos);
+
+ m_ObjectInfo[objnum].type = 1;
+ }
+ }
+ }
+ m_pSyntax->RestorePos(SavedPos + count * recordsize);
+ return TRUE;
+}
+
+bool CPDF_Parser::LoadCrossRefV4(FX_FILESIZE pos,
+ FX_FILESIZE streampos,
+ FX_BOOL bSkip) {
+ m_pSyntax->RestorePos(pos);
+ if (m_pSyntax->GetKeyword() != "xref")
+ return false;
+
+ m_SortedOffset.insert(pos);
+ if (streampos)
+ m_SortedOffset.insert(streampos);
+
+ while (1) {
+ FX_FILESIZE SavedPos = m_pSyntax->SavePos();
+ bool bIsNumber;
+ CFX_ByteString word = m_pSyntax->GetNextWord(&bIsNumber);
+ if (word.IsEmpty())
+ return false;
+
+ if (!bIsNumber) {
+ m_pSyntax->RestorePos(SavedPos);
+ break;
+ }
+
+ uint32_t start_objnum = FXSYS_atoui(word.c_str());
+ if (start_objnum >= kMaxObjectNumber)
+ return false;
+
+ uint32_t count = m_pSyntax->GetDirectNum();
+ m_pSyntax->ToNextWord();
+ SavedPos = m_pSyntax->SavePos();
+ const int32_t recordsize = 20;
+
+ m_dwXrefStartObjNum = start_objnum;
+ if (!bSkip) {
+ std::vector<char> buf(1024 * recordsize + 1);
+ buf[1024 * recordsize] = '\0';
+
+ int32_t nBlocks = count / 1024 + 1;
+ for (int32_t block = 0; block < nBlocks; block++) {
+ int32_t block_size = block == nBlocks - 1 ? count % 1024 : 1024;
+ m_pSyntax->ReadBlock(reinterpret_cast<uint8_t*>(buf.data()),
+ block_size * recordsize);
+
+ for (int32_t i = 0; i < block_size; i++) {
+ uint32_t objnum = start_objnum + block * 1024 + i;
+ char* pEntry = &buf[i * recordsize];
+ if (pEntry[17] == 'f') {
+ m_ObjectInfo[objnum].pos = 0;
+ m_ObjectInfo[objnum].type = 0;
+ } else {
+ FX_FILESIZE offset = (FX_FILESIZE)FXSYS_atoi64(pEntry);
+ if (offset == 0) {
+ for (int32_t c = 0; c < 10; c++) {
+ if (!std::isdigit(pEntry[c]))
+ return false;
+ }
+ }
+
+ m_ObjectInfo[objnum].pos = offset;
+ int32_t version = FXSYS_atoi(pEntry + 11);
+ if (version >= 1)
+ m_bVersionUpdated = true;
+
+ m_ObjectInfo[objnum].gennum = version;
+ if (m_ObjectInfo[objnum].pos < m_pSyntax->m_FileLen)
+ m_SortedOffset.insert(m_ObjectInfo[objnum].pos);
+
+ m_ObjectInfo[objnum].type = 1;
+ }
+ }
+ }
+ }
+ m_pSyntax->RestorePos(SavedPos + count * recordsize);
+ }
+ return !streampos || LoadCrossRefV5(&streampos, FALSE);
+}
+
+FX_BOOL CPDF_Parser::LoadAllCrossRefV5(FX_FILESIZE xrefpos) {
+ if (!LoadCrossRefV5(&xrefpos, TRUE))
+ return FALSE;
+
+ std::set<FX_FILESIZE> seen_xrefpos;
+ while (xrefpos) {
+ seen_xrefpos.insert(xrefpos);
+ if (!LoadCrossRefV5(&xrefpos, FALSE))
+ return FALSE;
+
+ // Check for circular references.
+ if (pdfium::ContainsKey(seen_xrefpos, xrefpos))
+ return FALSE;
+ }
+ m_ObjectStreamMap.clear();
+ m_bXRefStream = TRUE;
+ return TRUE;
+}
+
+FX_BOOL CPDF_Parser::RebuildCrossRef() {
+ m_ObjectInfo.clear();
+ m_SortedOffset.clear();
+ if (m_pTrailer) {
+ m_pTrailer->Release();
+ m_pTrailer = nullptr;
+ }
+
+ ParserState state = ParserState::kDefault;
+
+ int32_t inside_index = 0;
+ uint32_t objnum = 0;
+ uint32_t gennum = 0;
+ int32_t depth = 0;
+
+ const uint32_t kBufferSize = 4096;
+ std::vector<uint8_t> buffer(kBufferSize);
+
+ FX_FILESIZE pos = m_pSyntax->m_HeaderOffset;
+ FX_FILESIZE start_pos = 0;
+ FX_FILESIZE start_pos1 = 0;
+ FX_FILESIZE last_obj = -1;
+ FX_FILESIZE last_xref = -1;
+ FX_FILESIZE last_trailer = -1;
+
+ while (pos < m_pSyntax->m_FileLen) {
+ const FX_FILESIZE saved_pos = pos;
+ bool bOverFlow = false;
+ uint32_t size =
+ std::min((uint32_t)(m_pSyntax->m_FileLen - pos), kBufferSize);
+ if (!m_pSyntax->m_pFileAccess->ReadBlock(buffer.data(), pos, size))
+ break;
+
+ for (uint32_t i = 0; i < size; i++) {
+ uint8_t byte = buffer[i];
+ switch (state) {
+ case ParserState::kDefault:
+ if (PDFCharIsWhitespace(byte)) {
+ state = ParserState::kWhitespace;
+ } else if (std::isdigit(byte)) {
+ --i;
+ state = ParserState::kWhitespace;
+ } else if (byte == '%') {
+ inside_index = 0;
+ state = ParserState::kComment;
+ } else if (byte == '(') {
+ state = ParserState::kString;
+ depth = 1;
+ } else if (byte == '<') {
+ inside_index = 1;
+ state = ParserState::kHexString;
+ } else if (byte == '\\') {
+ state = ParserState::kEscapedString;
+ } else if (byte == 't') {
+ state = ParserState::kTrailer;
+ inside_index = 1;
+ }
+ break;
+
+ case ParserState::kWhitespace:
+ if (std::isdigit(byte)) {
+ start_pos = pos + i;
+ state = ParserState::kObjNum;
+ objnum = FXSYS_toDecimalDigit(static_cast<FX_WCHAR>(byte));
+ } else if (byte == 't') {
+ state = ParserState::kTrailer;
+ inside_index = 1;
+ } else if (byte == 'x') {
+ state = ParserState::kXref;
+ inside_index = 1;
+ } else if (!PDFCharIsWhitespace(byte)) {
+ --i;
+ state = ParserState::kDefault;
+ }
+ break;
+
+ case ParserState::kObjNum:
+ if (std::isdigit(byte)) {
+ objnum =
+ objnum * 10 + FXSYS_toDecimalDigit(static_cast<FX_WCHAR>(byte));
+ } else if (PDFCharIsWhitespace(byte)) {
+ state = ParserState::kPostObjNum;
+ } else {
+ --i;
+ state = ParserState::kEndObj;
+ inside_index = 0;
+ }
+ break;
+
+ case ParserState::kPostObjNum:
+ if (std::isdigit(byte)) {
+ start_pos1 = pos + i;
+ state = ParserState::kGenNum;
+ gennum = FXSYS_toDecimalDigit(static_cast<FX_WCHAR>(byte));
+ } else if (byte == 't') {
+ state = ParserState::kTrailer;
+ inside_index = 1;
+ } else if (!PDFCharIsWhitespace(byte)) {
+ --i;
+ state = ParserState::kDefault;
+ }
+ break;
+
+ case ParserState::kGenNum:
+ if (std::isdigit(byte)) {
+ gennum =
+ gennum * 10 + FXSYS_toDecimalDigit(static_cast<FX_WCHAR>(byte));
+ } else if (PDFCharIsWhitespace(byte)) {
+ state = ParserState::kPostGenNum;
+ } else {
+ --i;
+ state = ParserState::kDefault;
+ }
+ break;
+
+ case ParserState::kPostGenNum:
+ if (byte == 'o') {
+ state = ParserState::kBeginObj;
+ inside_index = 1;
+ } else if (std::isdigit(byte)) {
+ objnum = gennum;
+ gennum = FXSYS_toDecimalDigit(static_cast<FX_WCHAR>(byte));
+ start_pos = start_pos1;
+ start_pos1 = pos + i;
+ state = ParserState::kGenNum;
+ } else if (byte == 't') {
+ state = ParserState::kTrailer;
+ inside_index = 1;
+ } else if (!PDFCharIsWhitespace(byte)) {
+ --i;
+ state = ParserState::kDefault;
+ }
+ break;
+
+ case ParserState::kBeginObj:
+ switch (inside_index) {
+ case 1:
+ if (byte != 'b') {
+ --i;
+ state = ParserState::kDefault;
+ } else {
+ inside_index++;
+ }
+ break;
+ case 2:
+ if (byte != 'j') {
+ --i;
+ state = ParserState::kDefault;
+ } else {
+ inside_index++;
+ }
+ break;
+ case 3:
+ if (PDFCharIsWhitespace(byte) || PDFCharIsDelimiter(byte)) {
+ FX_FILESIZE obj_pos = start_pos - m_pSyntax->m_HeaderOffset;
+ m_SortedOffset.insert(obj_pos);
+ last_obj = start_pos;
+ FX_FILESIZE obj_end = 0;
+ CPDF_Object* pObject = ParseIndirectObjectAtByStrict(
+ m_pDocument, obj_pos, objnum, &obj_end);
+ if (CPDF_Stream* pStream = ToStream(pObject)) {
+ if (CPDF_Dictionary* pDict = pStream->GetDict()) {
+ if ((pDict->KeyExist("Type")) &&
+ (pDict->GetStringFor("Type") == "XRef" &&
+ pDict->KeyExist("Size"))) {
+ CPDF_Object* pRoot = pDict->GetObjectFor("Root");
+ if (pRoot && pRoot->GetDict() &&
+ pRoot->GetDict()->GetObjectFor("Pages")) {
+ if (m_pTrailer)
+ m_pTrailer->Release();
+ m_pTrailer = ToDictionary(pDict->Clone());
+ }
+ }
+ }
+ }
+
+ FX_FILESIZE offset = 0;
+ m_pSyntax->RestorePos(obj_pos);
+ offset = m_pSyntax->FindTag("obj", 0);
+ if (offset == -1)
+ offset = 0;
+ else
+ offset += 3;
+
+ FX_FILESIZE nLen = obj_end - obj_pos - offset;
+ if ((uint32_t)nLen > size - i) {
+ pos = obj_end + m_pSyntax->m_HeaderOffset;
+ bOverFlow = true;
+ } else {
+ i += (uint32_t)nLen;
+ }
+
+ if (!m_ObjectInfo.empty() && IsValidObjectNumber(objnum) &&
+ m_ObjectInfo[objnum].pos) {
+ if (pObject) {
+ uint32_t oldgen = GetObjectGenNum(objnum);
+ m_ObjectInfo[objnum].pos = obj_pos;
+ m_ObjectInfo[objnum].gennum = gennum;
+ if (oldgen != gennum)
+ m_bVersionUpdated = true;
+ }
+ } else {
+ m_ObjectInfo[objnum].pos = obj_pos;
+ m_ObjectInfo[objnum].type = 1;
+ m_ObjectInfo[objnum].gennum = gennum;
+ }
+
+ if (pObject)
+ pObject->Release();
+ }
+ --i;
+ state = ParserState::kDefault;
+ break;
+ }
+ break;
+
+ case ParserState::kTrailer:
+ if (inside_index == 7) {
+ if (PDFCharIsWhitespace(byte) || PDFCharIsDelimiter(byte)) {
+ last_trailer = pos + i - 7;
+ m_pSyntax->RestorePos(pos + i - m_pSyntax->m_HeaderOffset);
+
+ CPDF_Object* pObj = m_pSyntax->GetObject(m_pDocument, 0, 0, true);
+ if (pObj) {
+ if (!pObj->IsDictionary() && !pObj->AsStream()) {
+ pObj->Release();
+ } else {
+ CPDF_Stream* pStream = pObj->AsStream();
+ if (CPDF_Dictionary* pTrailer =
+ pStream ? pStream->GetDict() : pObj->AsDictionary()) {
+ if (m_pTrailer) {
+ CPDF_Object* pRoot = pTrailer->GetObjectFor("Root");
+ CPDF_Reference* pRef = ToReference(pRoot);
+ if (!pRoot ||
+ (pRef && IsValidObjectNumber(pRef->GetRefObjNum()) &&
+ m_ObjectInfo[pRef->GetRefObjNum()].pos != 0)) {
+ auto it = pTrailer->begin();
+ while (it != pTrailer->end()) {
+ const CFX_ByteString& key = it->first;
+ CPDF_Object* pElement = it->second;
+ ++it;
+ uint32_t dwObjNum =
+ pElement ? pElement->GetObjNum() : 0;
+ if (dwObjNum) {
+ m_pTrailer->SetReferenceFor(key, m_pDocument,
+ dwObjNum);
+ } else {
+ m_pTrailer->SetFor(key, pElement->Clone());
+ }
+ }
+ }
+ pObj->Release();
+ } else {
+ if (pObj->IsStream()) {
+ m_pTrailer = ToDictionary(pTrailer->Clone());
+ pObj->Release();
+ } else {
+ m_pTrailer = pTrailer;
+ }
+
+ FX_FILESIZE dwSavePos = m_pSyntax->SavePos();
+ CFX_ByteString strWord = m_pSyntax->GetKeyword();
+ if (!strWord.Compare("startxref")) {
+ bool bNumber;
+ CFX_ByteString bsOffset =
+ m_pSyntax->GetNextWord(&bNumber);
+ if (bNumber)
+ m_LastXRefOffset = FXSYS_atoi(bsOffset.c_str());
+ }
+ m_pSyntax->RestorePos(dwSavePos);
+ }
+ } else {
+ pObj->Release();
+ }
+ }
+ }
+ }
+ --i;
+ state = ParserState::kDefault;
+ } else if (byte == "trailer"[inside_index]) {
+ inside_index++;
+ } else {
+ --i;
+ state = ParserState::kDefault;
+ }
+ break;
+
+ case ParserState::kXref:
+ if (inside_index == 4) {
+ last_xref = pos + i - 4;
+ state = ParserState::kWhitespace;
+ } else if (byte == "xref"[inside_index]) {
+ inside_index++;
+ } else {
+ --i;
+ state = ParserState::kDefault;
+ }
+ break;
+
+ case ParserState::kComment:
+ if (PDFCharIsLineEnding(byte))
+ state = ParserState::kDefault;
+ break;
+
+ case ParserState::kString:
+ if (byte == ')') {
+ if (depth > 0)
+ depth--;
+ } else if (byte == '(') {
+ depth++;
+ }
+
+ if (!depth)
+ state = ParserState::kDefault;
+ break;
+
+ case ParserState::kHexString:
+ if (byte == '>' || (byte == '<' && inside_index == 1))
+ state = ParserState::kDefault;
+ inside_index = 0;
+ break;
+
+ case ParserState::kEscapedString:
+ if (PDFCharIsDelimiter(byte) || PDFCharIsWhitespace(byte)) {
+ --i;
+ state = ParserState::kDefault;
+ }
+ break;
+
+ case ParserState::kEndObj:
+ if (PDFCharIsWhitespace(byte)) {
+ state = ParserState::kDefault;
+ } else if (byte == '%' || byte == '(' || byte == '<' ||
+ byte == '\\') {
+ state = ParserState::kDefault;
+ --i;
+ } else if (inside_index == 6) {
+ state = ParserState::kDefault;
+ --i;
+ } else if (byte == "endobj"[inside_index]) {
+ inside_index++;
+ }
+ break;
+ }
+
+ if (bOverFlow) {
+ size = 0;
+ break;
+ }
+ }
+ pos += size;
+
+ // If the position has not changed at all or went backwards in a loop
+ // iteration, then break out to prevent infinite looping.
+ if (pos <= saved_pos)
+ break;
+ }
+
+ if (last_xref != -1 && last_xref > last_obj)
+ last_trailer = last_xref;
+ else if (last_trailer == -1 || last_xref < last_obj)
+ last_trailer = m_pSyntax->m_FileLen;
+
+ m_SortedOffset.insert(last_trailer - m_pSyntax->m_HeaderOffset);
+ return m_pTrailer && !m_ObjectInfo.empty();
+}
+
+FX_BOOL CPDF_Parser::LoadCrossRefV5(FX_FILESIZE* pos, FX_BOOL bMainXRef) {
+ CPDF_Object* pObject = ParseIndirectObjectAt(m_pDocument, *pos, 0);
+ if (!pObject)
+ return FALSE;
+
+ if (m_pDocument) {
+ CPDF_Dictionary* pRootDict = m_pDocument->GetRoot();
+ if (pRootDict && pRootDict->GetObjNum() == pObject->m_ObjNum) {
+ // If |pObject| has an objnum assigned then this will leak as Release()
+ // will early exit.
+ if (pObject->IsStream())
+ pObject->Release();
+ return FALSE;
+ }
+ if (!m_pDocument->ReplaceIndirectObjectIfHigherGeneration(pObject->m_ObjNum,
+ pObject)) {
+ return FALSE;
+ }
+ }
+
+ CPDF_Stream* pStream = pObject->AsStream();
+ if (!pStream)
+ return FALSE;
+
+ CPDF_Dictionary* pDict = pStream->GetDict();
+ *pos = pDict->GetIntegerFor("Prev");
+ int32_t size = pDict->GetIntegerFor("Size");
+ if (size < 0) {
+ pStream->Release();
+ return FALSE;
+ }
+
+ CPDF_Dictionary* pNewTrailer = ToDictionary(pDict->Clone());
+ if (bMainXRef) {
+ m_pTrailer = pNewTrailer;
+ ShrinkObjectMap(size);
+ for (auto& it : m_ObjectInfo)
+ it.second.type = 0;
+ } else {
+ m_Trailers.Add(pNewTrailer);
+ }
+
+ std::vector<std::pair<int32_t, int32_t>> arrIndex;
+ CPDF_Array* pArray = pDict->GetArrayFor("Index");
+ if (pArray) {
+ for (size_t i = 0; i < pArray->GetCount() / 2; i++) {
+ CPDF_Object* pStartNumObj = pArray->GetObjectAt(i * 2);
+ CPDF_Object* pCountObj = pArray->GetObjectAt(i * 2 + 1);
+
+ if (ToNumber(pStartNumObj) && ToNumber(pCountObj)) {
+ int nStartNum = pStartNumObj->GetInteger();
+ int nCount = pCountObj->GetInteger();
+ if (nStartNum >= 0 && nCount > 0)
+ arrIndex.push_back(std::make_pair(nStartNum, nCount));
+ }
+ }
+ }
+
+ if (arrIndex.size() == 0)
+ arrIndex.push_back(std::make_pair(0, size));
+
+ pArray = pDict->GetArrayFor("W");
+ if (!pArray) {
+ pStream->Release();
+ return FALSE;
+ }
+
+ CFX_ArrayTemplate<uint32_t> WidthArray;
+ FX_SAFE_UINT32 dwAccWidth = 0;
+ for (size_t i = 0; i < pArray->GetCount(); ++i) {
+ WidthArray.Add(pArray->GetIntegerAt(i));
+ dwAccWidth += WidthArray[i];
+ }
+
+ if (!dwAccWidth.IsValid() || WidthArray.GetSize() < 3) {
+ pStream->Release();
+ return FALSE;
+ }
+
+ uint32_t totalWidth = dwAccWidth.ValueOrDie();
+ CPDF_StreamAcc acc;
+ acc.LoadAllData(pStream);
+
+ const uint8_t* pData = acc.GetData();
+ uint32_t dwTotalSize = acc.GetSize();
+ uint32_t segindex = 0;
+ for (uint32_t i = 0; i < arrIndex.size(); i++) {
+ int32_t startnum = arrIndex[i].first;
+ if (startnum < 0)
+ continue;
+
+ m_dwXrefStartObjNum =
+ pdfium::base::checked_cast<uint32_t, int32_t>(startnum);
+ uint32_t count =
+ pdfium::base::checked_cast<uint32_t, int32_t>(arrIndex[i].second);
+ FX_SAFE_UINT32 dwCaculatedSize = segindex;
+ dwCaculatedSize += count;
+ dwCaculatedSize *= totalWidth;
+ if (!dwCaculatedSize.IsValid() ||
+ dwCaculatedSize.ValueOrDie() > dwTotalSize) {
+ continue;
+ }
+
+ const uint8_t* segstart = pData + segindex * totalWidth;
+ FX_SAFE_UINT32 dwMaxObjNum = startnum;
+ dwMaxObjNum += count;
+ uint32_t dwV5Size = m_ObjectInfo.empty() ? 0 : GetLastObjNum() + 1;
+ if (!dwMaxObjNum.IsValid() || dwMaxObjNum.ValueOrDie() > dwV5Size)
+ continue;
+
+ for (uint32_t j = 0; j < count; j++) {
+ int32_t type = 1;
+ const uint8_t* entrystart = segstart + j * totalWidth;
+ if (WidthArray[0])
+ type = GetVarInt(entrystart, WidthArray[0]);
+
+ if (GetObjectType(startnum + j) == 255) {
+ FX_FILESIZE offset =
+ GetVarInt(entrystart + WidthArray[0], WidthArray[1]);
+ m_ObjectInfo[startnum + j].pos = offset;
+ m_SortedOffset.insert(offset);
+ continue;
+ }
+
+ if (GetObjectType(startnum + j))
+ continue;
+
+ m_ObjectInfo[startnum + j].type = type;
+ if (type == 0) {
+ m_ObjectInfo[startnum + j].pos = 0;
+ } else {
+ FX_FILESIZE offset =
+ GetVarInt(entrystart + WidthArray[0], WidthArray[1]);
+ m_ObjectInfo[startnum + j].pos = offset;
+ if (type == 1) {
+ m_SortedOffset.insert(offset);
+ } else {
+ if (offset < 0 || !IsValidObjectNumber(offset)) {
+ pStream->Release();
+ return FALSE;
+ }
+ m_ObjectInfo[offset].type = 255;
+ }
+ }
+ }
+ segindex += count;
+ }
+ pStream->Release();
+ return TRUE;
+}
+
+CPDF_Array* CPDF_Parser::GetIDArray() {
+ CPDF_Object* pID = m_pTrailer ? m_pTrailer->GetObjectFor("ID") : nullptr;
+ if (!pID)
+ return nullptr;
+
+ if (CPDF_Reference* pRef = pID->AsReference()) {
+ pID = ParseIndirectObject(nullptr, pRef->GetRefObjNum());
+ m_pTrailer->SetFor("ID", pID);
+ }
+ return ToArray(pID);
+}
+
+uint32_t CPDF_Parser::GetRootObjNum() {
+ CPDF_Reference* pRef =
+ ToReference(m_pTrailer ? m_pTrailer->GetObjectFor("Root") : nullptr);
+ return pRef ? pRef->GetRefObjNum() : 0;
+}
+
+uint32_t CPDF_Parser::GetInfoObjNum() {
+ CPDF_Reference* pRef =
+ ToReference(m_pTrailer ? m_pTrailer->GetObjectFor("Info") : nullptr);
+ return pRef ? pRef->GetRefObjNum() : 0;
+}
+
+CPDF_Object* CPDF_Parser::ParseIndirectObject(
+ CPDF_IndirectObjectHolder* pObjList,
+ uint32_t objnum) {
+ if (!IsValidObjectNumber(objnum))
+ return nullptr;
+
+ // Prevent circular parsing the same object.
+ if (pdfium::ContainsKey(m_ParsingObjNums, objnum))
+ return nullptr;
+
+ pdfium::ScopedSetInsertion<uint32_t> local_insert(&m_ParsingObjNums, objnum);
+ if (GetObjectType(objnum) == 1 || GetObjectType(objnum) == 255) {
+ FX_FILESIZE pos = m_ObjectInfo[objnum].pos;
+ if (pos <= 0)
+ return nullptr;
+ return ParseIndirectObjectAt(pObjList, pos, objnum);
+ }
+ if (GetObjectType(objnum) != 2)
+ return nullptr;
+
+ CPDF_StreamAcc* pObjStream = GetObjectStream(m_ObjectInfo[objnum].pos);
+ if (!pObjStream)
+ return nullptr;
+
+ ScopedFileStream file(FX_CreateMemoryStream(
+ (uint8_t*)pObjStream->GetData(), (size_t)pObjStream->GetSize(), FALSE));
+ CPDF_SyntaxParser syntax;
+ syntax.InitParser(file.get(), 0);
+ const int32_t offset = GetStreamFirst(pObjStream);
+
+ // Read object numbers from |pObjStream| into a cache.
+ if (!pdfium::ContainsKey(m_ObjCache, pObjStream)) {
+ for (int32_t i = GetStreamNCount(pObjStream); i > 0; --i) {
+ uint32_t thisnum = syntax.GetDirectNum();
+ uint32_t thisoff = syntax.GetDirectNum();
+ m_ObjCache[pObjStream][thisnum] = thisoff;
+ }
+ }
+
+ const auto it = m_ObjCache[pObjStream].find(objnum);
+ if (it == m_ObjCache[pObjStream].end())
+ return nullptr;
+
+ syntax.RestorePos(offset + it->second);
+ return syntax.GetObject(pObjList, 0, 0, true);
+}
+
+CPDF_StreamAcc* CPDF_Parser::GetObjectStream(uint32_t objnum) {
+ auto it = m_ObjectStreamMap.find(objnum);
+ if (it != m_ObjectStreamMap.end())
+ return it->second.get();
+
+ if (!m_pDocument)
+ return nullptr;
+
+ const CPDF_Stream* pStream =
+ ToStream(m_pDocument->GetOrParseIndirectObject(objnum));
+ if (!pStream)
+ return nullptr;
+
+ CPDF_StreamAcc* pStreamAcc = new CPDF_StreamAcc;
+ pStreamAcc->LoadAllData(pStream);
+ m_ObjectStreamMap[objnum].reset(pStreamAcc);
+ return pStreamAcc;
+}
+
+FX_FILESIZE CPDF_Parser::GetObjectSize(uint32_t objnum) const {
+ if (!IsValidObjectNumber(objnum))
+ return 0;
+
+ if (GetObjectType(objnum) == 2)
+ objnum = GetObjectPositionOrZero(objnum);
+
+ if (GetObjectType(objnum) != 1 && GetObjectType(objnum) != 255)
+ return 0;
+
+ FX_FILESIZE offset = GetObjectPositionOrZero(objnum);
+ if (offset == 0)
+ return 0;
+
+ auto it = m_SortedOffset.find(offset);
+ if (it == m_SortedOffset.end() || ++it == m_SortedOffset.end())
+ return 0;
+
+ return *it - offset;
+}
+
+void CPDF_Parser::GetIndirectBinary(uint32_t objnum,
+ uint8_t*& pBuffer,
+ uint32_t& size) {
+ pBuffer = nullptr;
+ size = 0;
+ if (!IsValidObjectNumber(objnum))
+ return;
+
+ if (GetObjectType(objnum) == 2) {
+ CPDF_StreamAcc* pObjStream = GetObjectStream(m_ObjectInfo[objnum].pos);
+ if (!pObjStream)
+ return;
+
+ int32_t offset = GetStreamFirst(pObjStream);
+ const uint8_t* pData = pObjStream->GetData();
+ uint32_t totalsize = pObjStream->GetSize();
+ ScopedFileStream file(
+ FX_CreateMemoryStream((uint8_t*)pData, (size_t)totalsize, FALSE));
+
+ CPDF_SyntaxParser syntax;
+ syntax.InitParser(file.get(), 0);
+ for (int i = GetStreamNCount(pObjStream); i > 0; --i) {
+ uint32_t thisnum = syntax.GetDirectNum();
+ uint32_t thisoff = syntax.GetDirectNum();
+ if (thisnum != objnum)
+ continue;
+
+ if (i == 1) {
+ size = totalsize - (thisoff + offset);
+ } else {
+ syntax.GetDirectNum(); // Skip nextnum.
+ uint32_t nextoff = syntax.GetDirectNum();
+ size = nextoff - thisoff;
+ }
+
+ pBuffer = FX_Alloc(uint8_t, size);
+ FXSYS_memcpy(pBuffer, pData + thisoff + offset, size);
+ return;
+ }
+ return;
+ }
+
+ if (GetObjectType(objnum) != 1)
+ return;
+
+ FX_FILESIZE pos = m_ObjectInfo[objnum].pos;
+ if (pos == 0)
+ return;
+
+ FX_FILESIZE SavedPos = m_pSyntax->SavePos();
+ m_pSyntax->RestorePos(pos);
+
+ bool bIsNumber;
+ CFX_ByteString word = m_pSyntax->GetNextWord(&bIsNumber);
+ if (!bIsNumber) {
+ m_pSyntax->RestorePos(SavedPos);
+ return;
+ }
+
+ uint32_t parser_objnum = FXSYS_atoui(word.c_str());
+ if (parser_objnum && parser_objnum != objnum) {
+ m_pSyntax->RestorePos(SavedPos);
+ return;
+ }
+
+ word = m_pSyntax->GetNextWord(&bIsNumber);
+ if (!bIsNumber) {
+ m_pSyntax->RestorePos(SavedPos);
+ return;
+ }
+
+ if (m_pSyntax->GetKeyword() != "obj") {
+ m_pSyntax->RestorePos(SavedPos);
+ return;
+ }
+
+ auto it = m_SortedOffset.find(pos);
+ if (it == m_SortedOffset.end() || ++it == m_SortedOffset.end()) {
+ m_pSyntax->RestorePos(SavedPos);
+ return;
+ }
+
+ FX_FILESIZE nextoff = *it;
+ FX_BOOL bNextOffValid = FALSE;
+ if (nextoff != pos) {
+ m_pSyntax->RestorePos(nextoff);
+ word = m_pSyntax->GetNextWord(&bIsNumber);
+ if (word == "xref") {
+ bNextOffValid = TRUE;
+ } else if (bIsNumber) {
+ word = m_pSyntax->GetNextWord(&bIsNumber);
+ if (bIsNumber && m_pSyntax->GetKeyword() == "obj") {
+ bNextOffValid = TRUE;
+ }
+ }
+ }
+
+ if (!bNextOffValid) {
+ m_pSyntax->RestorePos(pos);
+ while (1) {
+ if (m_pSyntax->GetKeyword() == "endobj")
+ break;
+
+ if (m_pSyntax->SavePos() == m_pSyntax->m_FileLen)
+ break;
+ }
+ nextoff = m_pSyntax->SavePos();
+ }
+
+ size = (uint32_t)(nextoff - pos);
+ pBuffer = FX_Alloc(uint8_t, size);
+ m_pSyntax->RestorePos(pos);
+ m_pSyntax->ReadBlock(pBuffer, size);
+ m_pSyntax->RestorePos(SavedPos);
+}
+
+CPDF_Object* CPDF_Parser::ParseIndirectObjectAt(
+ CPDF_IndirectObjectHolder* pObjList,
+ FX_FILESIZE pos,
+ uint32_t objnum) {
+ FX_FILESIZE SavedPos = m_pSyntax->SavePos();
+ m_pSyntax->RestorePos(pos);
+ bool bIsNumber;
+ CFX_ByteString word = m_pSyntax->GetNextWord(&bIsNumber);
+ if (!bIsNumber) {
+ m_pSyntax->RestorePos(SavedPos);
+ return nullptr;
+ }
+
+ FX_FILESIZE objOffset = m_pSyntax->SavePos();
+ objOffset -= word.GetLength();
+ uint32_t parser_objnum = FXSYS_atoui(word.c_str());
+ if (objnum && parser_objnum != objnum) {
+ m_pSyntax->RestorePos(SavedPos);
+ return nullptr;
+ }
+
+ word = m_pSyntax->GetNextWord(&bIsNumber);
+ if (!bIsNumber) {
+ m_pSyntax->RestorePos(SavedPos);
+ return nullptr;
+ }
+
+ uint32_t parser_gennum = FXSYS_atoui(word.c_str());
+ if (m_pSyntax->GetKeyword() != "obj") {
+ m_pSyntax->RestorePos(SavedPos);
+ return nullptr;
+ }
+
+ CPDF_Object* pObj =
+ m_pSyntax->GetObject(pObjList, objnum, parser_gennum, true);
+ m_pSyntax->SavePos();
+
+ CFX_ByteString bsWord = m_pSyntax->GetKeyword();
+ if (bsWord == "endobj")
+ m_pSyntax->SavePos();
+
+ m_pSyntax->RestorePos(SavedPos);
+ if (pObj) {
+ if (!objnum)
+ pObj->m_ObjNum = parser_objnum;
+ pObj->m_GenNum = parser_gennum;
+ }
+ return pObj;
+}
+
+CPDF_Object* CPDF_Parser::ParseIndirectObjectAtByStrict(
+ CPDF_IndirectObjectHolder* pObjList,
+ FX_FILESIZE pos,
+ uint32_t objnum,
+ FX_FILESIZE* pResultPos) {
+ FX_FILESIZE SavedPos = m_pSyntax->SavePos();
+ m_pSyntax->RestorePos(pos);
+
+ bool bIsNumber;
+ CFX_ByteString word = m_pSyntax->GetNextWord(&bIsNumber);
+ if (!bIsNumber) {
+ m_pSyntax->RestorePos(SavedPos);
+ return nullptr;
+ }
+
+ uint32_t parser_objnum = FXSYS_atoui(word.c_str());
+ if (objnum && parser_objnum != objnum) {
+ m_pSyntax->RestorePos(SavedPos);
+ return nullptr;
+ }
+
+ word = m_pSyntax->GetNextWord(&bIsNumber);
+ if (!bIsNumber) {
+ m_pSyntax->RestorePos(SavedPos);
+ return nullptr;
+ }
+
+ uint32_t gennum = FXSYS_atoui(word.c_str());
+ if (m_pSyntax->GetKeyword() != "obj") {
+ m_pSyntax->RestorePos(SavedPos);
+ return nullptr;
+ }
+
+ CPDF_Object* pObj = m_pSyntax->GetObjectForStrict(pObjList, objnum, gennum);
+ if (pResultPos)
+ *pResultPos = m_pSyntax->m_Pos;
+
+ m_pSyntax->RestorePos(SavedPos);
+ return pObj;
+}
+
+CPDF_Dictionary* CPDF_Parser::LoadTrailerV4() {
+ if (m_pSyntax->GetKeyword() != "trailer")
+ return nullptr;
+
+ std::unique_ptr<CPDF_Object, ReleaseDeleter<CPDF_Object>> pObj(
+ m_pSyntax->GetObject(m_pDocument, 0, 0, true));
+ if (!ToDictionary(pObj.get()))
+ return nullptr;
+ return pObj.release()->AsDictionary();
+}
+
+uint32_t CPDF_Parser::GetPermissions() const {
+ if (!m_pSecurityHandler)
+ return 0xFFFFFFFF;
+
+ uint32_t dwPermission = m_pSecurityHandler->GetPermissions();
+ if (m_pEncryptDict && m_pEncryptDict->GetStringFor("Filter") == "Standard") {
+ // See PDF Reference 1.7, page 123, table 3.20.
+ dwPermission &= 0xFFFFFFFC;
+ dwPermission |= 0xFFFFF0C0;
+ }
+ return dwPermission;
+}
+
+FX_BOOL CPDF_Parser::IsLinearizedFile(IFX_FileRead* pFileAccess,
+ uint32_t offset) {
+ m_pSyntax->InitParser(pFileAccess, offset);
+ m_pSyntax->RestorePos(m_pSyntax->m_HeaderOffset + 9);
+
+ FX_FILESIZE SavedPos = m_pSyntax->SavePos();
+ bool bIsNumber;
+ CFX_ByteString word = m_pSyntax->GetNextWord(&bIsNumber);
+ if (!bIsNumber)
+ return FALSE;
+
+ uint32_t objnum = FXSYS_atoui(word.c_str());
+ word = m_pSyntax->GetNextWord(&bIsNumber);
+ if (!bIsNumber)
+ return FALSE;
+
+ uint32_t gennum = FXSYS_atoui(word.c_str());
+ if (m_pSyntax->GetKeyword() != "obj") {
+ m_pSyntax->RestorePos(SavedPos);
+ return FALSE;
+ }
+
+ m_pLinearized = m_pSyntax->GetObject(nullptr, objnum, gennum, true);
+ if (!m_pLinearized)
+ return FALSE;
+
+ CPDF_Dictionary* pDict = m_pLinearized->GetDict();
+ if (pDict && pDict->GetObjectFor("Linearized")) {
+ m_pSyntax->GetNextWord(nullptr);
+
+ CPDF_Object* pLen = pDict->GetObjectFor("L");
+ if (!pLen) {
+ m_pLinearized->Release();
+ m_pLinearized = nullptr;
+ return FALSE;
+ }
+
+ if (pLen->GetInteger() != (int)pFileAccess->GetSize())
+ return FALSE;
+
+ if (CPDF_Number* pNo = ToNumber(pDict->GetObjectFor("P")))
+ m_dwFirstPageNo = pNo->GetInteger();
+
+ if (CPDF_Number* pTable = ToNumber(pDict->GetObjectFor("T")))
+ m_LastXRefOffset = pTable->GetInteger();
+
+ return TRUE;
+ }
+ m_pLinearized->Release();
+ m_pLinearized = nullptr;
+ return FALSE;
+}
+
+CPDF_Parser::Error CPDF_Parser::StartLinearizedParse(IFX_FileRead* pFileAccess,
+ CPDF_Document* pDocument) {
+ ASSERT(!m_bHasParsed);
+
+ m_bXRefStream = FALSE;
+ m_LastXRefOffset = 0;
+ m_bOwnFileRead = true;
+
+ int32_t offset = GetHeaderOffset(pFileAccess);
+ if (offset == -1)
+ return FORMAT_ERROR;
+
+ if (!IsLinearizedFile(pFileAccess, offset)) {
+ m_pSyntax->m_pFileAccess = nullptr;
+ return StartParse(pFileAccess, std::move(pDocument));
+ }
+ m_bHasParsed = true;
+ m_pDocument = pDocument;
+
+ FX_FILESIZE dwFirstXRefOffset = m_pSyntax->SavePos();
+
+ FX_BOOL bXRefRebuilt = FALSE;
+ FX_BOOL bLoadV4 = LoadCrossRefV4(dwFirstXRefOffset, 0, FALSE);
+ if (!bLoadV4 && !LoadCrossRefV5(&dwFirstXRefOffset, TRUE)) {
+ if (!RebuildCrossRef())
+ return FORMAT_ERROR;
+
+ bXRefRebuilt = TRUE;
+ m_LastXRefOffset = 0;
+ }
+
+ if (bLoadV4) {
+ m_pTrailer = LoadTrailerV4();
+ if (!m_pTrailer)
+ return SUCCESS;
+
+ int32_t xrefsize = GetDirectInteger(m_pTrailer, "Size");
+ if (xrefsize > 0)
+ ShrinkObjectMap(xrefsize);
+ }
+
+ Error eRet = SetEncryptHandler();
+ if (eRet != SUCCESS)
+ return eRet;
+
+ m_pDocument->LoadLinearizedDoc(m_pLinearized->GetDict());
+ if (!m_pDocument->GetRoot() || m_pDocument->GetPageCount() == 0) {
+ if (bXRefRebuilt)
+ return FORMAT_ERROR;
+
+ ReleaseEncryptHandler();
+ if (!RebuildCrossRef())
+ return FORMAT_ERROR;
+
+ eRet = SetEncryptHandler();
+ if (eRet != SUCCESS)
+ return eRet;
+
+ m_pDocument->LoadLinearizedDoc(m_pLinearized->GetDict());
+ if (!m_pDocument->GetRoot())
+ return FORMAT_ERROR;
+ }
+
+ if (GetRootObjNum() == 0) {
+ ReleaseEncryptHandler();
+ if (!RebuildCrossRef() || GetRootObjNum() == 0)
+ return FORMAT_ERROR;
+
+ eRet = SetEncryptHandler();
+ if (eRet != SUCCESS)
+ return eRet;
+ }
+
+ if (m_pSecurityHandler && m_pSecurityHandler->IsMetadataEncrypted()) {
+ if (CPDF_Reference* pMetadata =
+ ToReference(m_pDocument->GetRoot()->GetObjectFor("Metadata")))
+ m_pSyntax->m_MetadataObjnum = pMetadata->GetRefObjNum();
+ }
+ return SUCCESS;
+}
+
+FX_BOOL CPDF_Parser::LoadLinearizedAllCrossRefV5(FX_FILESIZE xrefpos) {
+ if (!LoadCrossRefV5(&xrefpos, FALSE))
+ return FALSE;
+
+ std::set<FX_FILESIZE> seen_xrefpos;
+ while (xrefpos) {
+ seen_xrefpos.insert(xrefpos);
+ if (!LoadCrossRefV5(&xrefpos, FALSE))
+ return FALSE;
+
+ // Check for circular references.
+ if (pdfium::ContainsKey(seen_xrefpos, xrefpos))
+ return FALSE;
+ }
+ m_ObjectStreamMap.clear();
+ m_bXRefStream = TRUE;
+ return TRUE;
+}
+
+CPDF_Parser::Error CPDF_Parser::LoadLinearizedMainXRefTable() {
+ uint32_t dwSaveMetadataObjnum = m_pSyntax->m_MetadataObjnum;
+ m_pSyntax->m_MetadataObjnum = 0;
+ if (m_pTrailer) {
+ m_pTrailer->Release();
+ m_pTrailer = nullptr;
+ }
+
+ m_pSyntax->RestorePos(m_LastXRefOffset - m_pSyntax->m_HeaderOffset);
+ uint8_t ch = 0;
+ uint32_t dwCount = 0;
+ m_pSyntax->GetNextChar(ch);
+ while (PDFCharIsWhitespace(ch)) {
+ ++dwCount;
+ if (m_pSyntax->m_FileLen >=
+ (FX_FILESIZE)(m_pSyntax->SavePos() + m_pSyntax->m_HeaderOffset)) {
+ break;
+ }
+ m_pSyntax->GetNextChar(ch);
+ }
+ m_LastXRefOffset += dwCount;
+ m_ObjectStreamMap.clear();
+ m_ObjCache.clear();
+
+ if (!LoadLinearizedAllCrossRefV4(m_LastXRefOffset, m_dwXrefStartObjNum) &&
+ !LoadLinearizedAllCrossRefV5(m_LastXRefOffset)) {
+ m_LastXRefOffset = 0;
+ m_pSyntax->m_MetadataObjnum = dwSaveMetadataObjnum;
+ return FORMAT_ERROR;
+ }
+
+ m_pSyntax->m_MetadataObjnum = dwSaveMetadataObjnum;
+ return SUCCESS;
+}