diff options
Diffstat (limited to 'core/src/fpdfapi/fpdf_parser/cpdf_hint_tables.cpp')
| -rw-r--r-- | core/src/fpdfapi/fpdf_parser/cpdf_hint_tables.cpp | 469 |
1 files changed, 0 insertions, 469 deletions
diff --git a/core/src/fpdfapi/fpdf_parser/cpdf_hint_tables.cpp b/core/src/fpdfapi/fpdf_parser/cpdf_hint_tables.cpp deleted file mode 100644 index 84464fcff2..0000000000 --- a/core/src/fpdfapi/fpdf_parser/cpdf_hint_tables.cpp +++ /dev/null @@ -1,469 +0,0 @@ -// 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/src/fpdfapi/fpdf_parser/cpdf_hint_tables.h" - -#include "core/include/fxcrt/fx_safe_types.h" -#include "core/include/fpdfapi/cpdf_array.h" -#include "core/include/fpdfapi/cpdf_dictionary.h" -#include "core/include/fpdfapi/cpdf_stream.h" -#include "core/src/fpdfapi/fpdf_parser/cpdf_data_avail.h" - -namespace { - -bool CanReadFromBitStream(const CFX_BitStream* hStream, - const FX_SAFE_DWORD& num_bits) { - return num_bits.IsValid() && - hStream->BitsRemaining() >= num_bits.ValueOrDie(); -} - -} // namespace - -CPDF_HintTables::~CPDF_HintTables() { - m_dwDeltaNObjsArray.RemoveAll(); - m_dwNSharedObjsArray.RemoveAll(); - m_dwSharedObjNumArray.RemoveAll(); - m_dwIdentifierArray.RemoveAll(); -} - -FX_DWORD CPDF_HintTables::GetItemLength( - int index, - const std::vector<FX_FILESIZE>& szArray) { - if (index < 0 || szArray.size() < 2 || - static_cast<size_t>(index) > szArray.size() - 2 || - szArray[index] > szArray[index + 1]) { - return 0; - } - return szArray[index + 1] - szArray[index]; -} - -FX_BOOL CPDF_HintTables::ReadPageHintTable(CFX_BitStream* hStream) { - if (!hStream || hStream->IsEOF()) - return FALSE; - - int nStreamOffset = ReadPrimaryHintStreamOffset(); - int nStreamLen = ReadPrimaryHintStreamLength(); - if (nStreamOffset < 0 || nStreamLen < 1) - return FALSE; - - const FX_DWORD kHeaderSize = 288; - if (hStream->BitsRemaining() < kHeaderSize) - return FALSE; - - // Item 1: The least number of objects in a page. - FX_DWORD dwObjLeastNum = hStream->GetBits(32); - - // Item 2: The location of the first page's page object. - FX_DWORD dwFirstObjLoc = hStream->GetBits(32); - if (dwFirstObjLoc > nStreamOffset) { - FX_SAFE_DWORD safeLoc = pdfium::base::checked_cast<FX_DWORD>(nStreamLen); - safeLoc += dwFirstObjLoc; - if (!safeLoc.IsValid()) - return FALSE; - m_szFirstPageObjOffset = - pdfium::base::checked_cast<FX_FILESIZE>(safeLoc.ValueOrDie()); - } else { - m_szFirstPageObjOffset = - pdfium::base::checked_cast<FX_FILESIZE>(dwFirstObjLoc); - } - - // Item 3: The number of bits needed to represent the difference - // between the greatest and least number of objects in a page. - FX_DWORD dwDeltaObjectsBits = hStream->GetBits(16); - - // Item 4: The least length of a page in bytes. - FX_DWORD dwPageLeastLen = hStream->GetBits(32); - - // Item 5: The number of bits needed to represent the difference - // between the greatest and least length of a page, in bytes. - FX_DWORD dwDeltaPageLenBits = hStream->GetBits(16); - - // Skip Item 6, 7, 8, 9 total 96 bits. - hStream->SkipBits(96); - - // Item 10: The number of bits needed to represent the greatest - // number of shared object references. - FX_DWORD dwSharedObjBits = hStream->GetBits(16); - - // Item 11: The number of bits needed to represent the numerically - // greatest shared object identifier used by the pages. - FX_DWORD dwSharedIdBits = hStream->GetBits(16); - - // Item 12: The number of bits needed to represent the numerator of - // the fractional position for each shared object reference. For each - // shared object referenced from a page, there is an indication of - // where in the page's content stream the object is first referenced. - FX_DWORD dwSharedNumeratorBits = hStream->GetBits(16); - - // Item 13: Skip Item 13 which has 16 bits. - hStream->SkipBits(16); - - CPDF_Object* pPageNum = m_pLinearizedDict->GetElementValue("N"); - int nPages = pPageNum ? pPageNum->GetInteger() : 0; - if (nPages < 1) - return FALSE; - - FX_SAFE_DWORD required_bits = dwDeltaObjectsBits; - required_bits *= pdfium::base::checked_cast<FX_DWORD>(nPages); - if (!CanReadFromBitStream(hStream, required_bits)) - return FALSE; - - for (int i = 0; i < nPages; ++i) { - FX_SAFE_DWORD safeDeltaObj = hStream->GetBits(dwDeltaObjectsBits); - safeDeltaObj += dwObjLeastNum; - if (!safeDeltaObj.IsValid()) - return FALSE; - m_dwDeltaNObjsArray.Add(safeDeltaObj.ValueOrDie()); - } - hStream->ByteAlign(); - - required_bits = dwDeltaPageLenBits; - required_bits *= pdfium::base::checked_cast<FX_DWORD>(nPages); - if (!CanReadFromBitStream(hStream, required_bits)) - return FALSE; - - CFX_DWordArray dwPageLenArray; - for (int i = 0; i < nPages; ++i) { - FX_SAFE_DWORD safePageLen = hStream->GetBits(dwDeltaPageLenBits); - safePageLen += dwPageLeastLen; - if (!safePageLen.IsValid()) - return FALSE; - dwPageLenArray.Add(safePageLen.ValueOrDie()); - } - - CPDF_Object* pOffsetE = m_pLinearizedDict->GetElementValue("E"); - int nOffsetE = pOffsetE ? pOffsetE->GetInteger() : -1; - if (nOffsetE < 0) - return FALSE; - - CPDF_Object* pFirstPageNum = m_pLinearizedDict->GetElementValue("P"); - int nFirstPageNum = pFirstPageNum ? pFirstPageNum->GetInteger() : 0; - for (int i = 0; i < nPages; ++i) { - if (i == nFirstPageNum) { - m_szPageOffsetArray.push_back(m_szFirstPageObjOffset); - } else if (i == nFirstPageNum + 1) { - if (i == 1) { - m_szPageOffsetArray.push_back(nOffsetE); - } else { - m_szPageOffsetArray.push_back(m_szPageOffsetArray[i - 2] + - dwPageLenArray[i - 2]); - } - } else { - if (i == 0) { - m_szPageOffsetArray.push_back(nOffsetE); - } else { - m_szPageOffsetArray.push_back(m_szPageOffsetArray[i - 1] + - dwPageLenArray[i - 1]); - } - } - } - - if (nPages > 0) { - m_szPageOffsetArray.push_back(m_szPageOffsetArray[nPages - 1] + - dwPageLenArray[nPages - 1]); - } - hStream->ByteAlign(); - - // Number of shared objects. - required_bits = dwSharedObjBits; - required_bits *= pdfium::base::checked_cast<FX_DWORD>(nPages); - if (!CanReadFromBitStream(hStream, required_bits)) - return FALSE; - - for (int i = 0; i < nPages; i++) - m_dwNSharedObjsArray.Add(hStream->GetBits(dwSharedObjBits)); - hStream->ByteAlign(); - - // Array of identifiers, size = nshared_objects. - for (int i = 0; i < nPages; i++) { - required_bits = dwSharedIdBits; - required_bits *= m_dwNSharedObjsArray[i]; - if (!CanReadFromBitStream(hStream, required_bits)) - return FALSE; - - for (int j = 0; j < m_dwNSharedObjsArray[i]; j++) - m_dwIdentifierArray.Add(hStream->GetBits(dwSharedIdBits)); - } - hStream->ByteAlign(); - - for (int i = 0; i < nPages; i++) { - FX_SAFE_DWORD safeSize = m_dwNSharedObjsArray[i]; - safeSize *= dwSharedNumeratorBits; - if (!CanReadFromBitStream(hStream, safeSize)) - return FALSE; - - hStream->SkipBits(safeSize.ValueOrDie()); - } - hStream->ByteAlign(); - - FX_SAFE_DWORD safeTotalPageLen = pdfium::base::checked_cast<FX_DWORD>(nPages); - safeTotalPageLen *= dwDeltaPageLenBits; - if (!CanReadFromBitStream(hStream, safeTotalPageLen)) - return FALSE; - - hStream->SkipBits(safeTotalPageLen.ValueOrDie()); - hStream->ByteAlign(); - return TRUE; -} - -FX_BOOL CPDF_HintTables::ReadSharedObjHintTable(CFX_BitStream* hStream, - FX_DWORD offset) { - if (!hStream || hStream->IsEOF()) - return FALSE; - - int nStreamOffset = ReadPrimaryHintStreamOffset(); - int nStreamLen = ReadPrimaryHintStreamLength(); - if (nStreamOffset < 0 || nStreamLen < 1) - return FALSE; - - FX_SAFE_DWORD bit_offset = offset; - bit_offset *= 8; - if (!bit_offset.IsValid() || hStream->GetPos() > bit_offset.ValueOrDie()) - return FALSE; - hStream->SkipBits(bit_offset.ValueOrDie() - hStream->GetPos()); - - const FX_DWORD kHeaderSize = 192; - if (hStream->BitsRemaining() < kHeaderSize) - return FALSE; - - // Item 1: The object number of the first object in the shared objects - // section. - FX_DWORD dwFirstSharedObjNum = hStream->GetBits(32); - - // Item 2: The location of the first object in the shared objects section. - FX_DWORD dwFirstSharedObjLoc = hStream->GetBits(32); - if (dwFirstSharedObjLoc > nStreamOffset) - dwFirstSharedObjLoc += nStreamLen; - - // Item 3: The number of shared object entries for the first page. - m_nFirstPageSharedObjs = hStream->GetBits(32); - - // Item 4: The number of shared object entries for the shared objects - // section, including the number of shared object entries for the first page. - FX_DWORD dwSharedObjTotal = hStream->GetBits(32); - - // Item 5: The number of bits needed to represent the greatest number of - // objects in a shared object group. Skipped. - hStream->SkipBits(16); - - // Item 6: The least length of a shared object group in bytes. - FX_DWORD dwGroupLeastLen = hStream->GetBits(32); - - // Item 7: The number of bits needed to represent the difference between the - // greatest and least length of a shared object group, in bytes. - FX_DWORD dwDeltaGroupLen = hStream->GetBits(16); - CPDF_Object* pFirstPageObj = m_pLinearizedDict->GetElementValue("O"); - int nFirstPageObjNum = pFirstPageObj ? pFirstPageObj->GetInteger() : -1; - if (nFirstPageObjNum < 0) - return FALSE; - - FX_DWORD dwPrevObjLen = 0; - FX_DWORD dwCurObjLen = 0; - FX_SAFE_DWORD required_bits = dwSharedObjTotal; - required_bits *= dwDeltaGroupLen; - if (!CanReadFromBitStream(hStream, required_bits)) - return FALSE; - - for (FX_DWORD i = 0; i < dwSharedObjTotal; ++i) { - dwPrevObjLen = dwCurObjLen; - FX_SAFE_DWORD safeObjLen = hStream->GetBits(dwDeltaGroupLen); - safeObjLen += dwGroupLeastLen; - if (!safeObjLen.IsValid()) - return FALSE; - - dwCurObjLen = safeObjLen.ValueOrDie(); - if (i < m_nFirstPageSharedObjs) { - m_dwSharedObjNumArray.Add(nFirstPageObjNum + i); - if (i == 0) - m_szSharedObjOffsetArray.push_back(m_szFirstPageObjOffset); - } else { - FX_SAFE_DWORD safeObjNum = dwFirstSharedObjNum; - safeObjNum += i - m_nFirstPageSharedObjs; - if (!safeObjNum.IsValid()) - return FALSE; - - m_dwSharedObjNumArray.Add(safeObjNum.ValueOrDie()); - if (i == m_nFirstPageSharedObjs) { - m_szSharedObjOffsetArray.push_back( - pdfium::base::checked_cast<int32_t>(dwFirstSharedObjLoc)); - } - } - - if (i != 0 && i != m_nFirstPageSharedObjs) { - FX_SAFE_INT32 safeLoc = pdfium::base::checked_cast<int32_t>(dwPrevObjLen); - safeLoc += m_szSharedObjOffsetArray[i - 1]; - if (!safeLoc.IsValid()) - return FALSE; - - m_szSharedObjOffsetArray.push_back(safeLoc.ValueOrDie()); - } - } - - if (dwSharedObjTotal > 0) { - FX_SAFE_INT32 safeLoc = pdfium::base::checked_cast<int32_t>(dwCurObjLen); - safeLoc += m_szSharedObjOffsetArray[dwSharedObjTotal - 1]; - if (!safeLoc.IsValid()) - return FALSE; - - m_szSharedObjOffsetArray.push_back(safeLoc.ValueOrDie()); - } - - hStream->ByteAlign(); - if (hStream->BitsRemaining() < dwSharedObjTotal) - return FALSE; - - hStream->SkipBits(dwSharedObjTotal); - hStream->ByteAlign(); - return TRUE; -} - -FX_BOOL CPDF_HintTables::GetPagePos(int index, - FX_FILESIZE& szPageStartPos, - FX_FILESIZE& szPageLength, - FX_DWORD& dwObjNum) { - if (!m_pLinearizedDict) - return FALSE; - - szPageStartPos = m_szPageOffsetArray[index]; - szPageLength = GetItemLength(index, m_szPageOffsetArray); - - CPDF_Object* pFirstPageNum = m_pLinearizedDict->GetElementValue("P"); - int nFirstPageNum = pFirstPageNum ? pFirstPageNum->GetInteger() : 0; - - CPDF_Object* pFirstPageObjNum = m_pLinearizedDict->GetElementValue("O"); - if (!pFirstPageObjNum) - return FALSE; - - int nFirstPageObjNum = pFirstPageObjNum->GetInteger(); - if (index == nFirstPageNum) { - dwObjNum = nFirstPageObjNum; - return TRUE; - } - - // The object number of remaining pages starts from 1. - dwObjNum = 1; - for (int i = 0; i < index; ++i) { - if (i == nFirstPageNum) - continue; - dwObjNum += m_dwDeltaNObjsArray[i]; - } - return TRUE; -} - -IPDF_DataAvail::DocAvailStatus CPDF_HintTables::CheckPage( - int index, - IPDF_DataAvail::DownloadHints* pHints) { - if (!m_pLinearizedDict || !pHints) - return IPDF_DataAvail::DataError; - - CPDF_Object* pFirstAvailPage = m_pLinearizedDict->GetElementValue("P"); - int nFirstAvailPage = pFirstAvailPage ? pFirstAvailPage->GetInteger() : 0; - if (index == nFirstAvailPage) - return IPDF_DataAvail::DataAvailable; - - FX_DWORD dwLength = GetItemLength(index, m_szPageOffsetArray); - // If two pages have the same offset, it should be treated as an error. - if (!dwLength) - return IPDF_DataAvail::DataError; - - if (!m_pDataAvail->IsDataAvail(m_szPageOffsetArray[index], dwLength, pHints)) - return IPDF_DataAvail::DataNotAvailable; - - // Download data of shared objects in the page. - FX_DWORD offset = 0; - for (int i = 0; i < index; ++i) - offset += m_dwNSharedObjsArray[i]; - - CPDF_Object* pFirstPageObj = m_pLinearizedDict->GetElementValue("O"); - int nFirstPageObjNum = pFirstPageObj ? pFirstPageObj->GetInteger() : -1; - if (nFirstPageObjNum < 0) - return IPDF_DataAvail::DataError; - - FX_DWORD dwIndex = 0; - FX_DWORD dwObjNum = 0; - for (int j = 0; j < m_dwNSharedObjsArray[index]; ++j) { - dwIndex = m_dwIdentifierArray[offset + j]; - if (dwIndex >= m_dwSharedObjNumArray.GetSize()) - return IPDF_DataAvail::DataNotAvailable; - - dwObjNum = m_dwSharedObjNumArray[dwIndex]; - if (dwObjNum >= nFirstPageObjNum && - dwObjNum < nFirstPageObjNum + m_nFirstPageSharedObjs) { - continue; - } - - dwLength = GetItemLength(dwIndex, m_szSharedObjOffsetArray); - // If two objects have the same offset, it should be treated as an error. - if (!dwLength) - return IPDF_DataAvail::DataError; - - if (!m_pDataAvail->IsDataAvail(m_szSharedObjOffsetArray[dwIndex], dwLength, - pHints)) { - return IPDF_DataAvail::DataNotAvailable; - } - } - return IPDF_DataAvail::DataAvailable; -} - -FX_BOOL CPDF_HintTables::LoadHintStream(CPDF_Stream* pHintStream) { - if (!pHintStream || !m_pLinearizedDict) - return FALSE; - - CPDF_Dictionary* pDict = pHintStream->GetDict(); - CPDF_Object* pOffset = pDict ? pDict->GetElement("S") : nullptr; - if (!pOffset || !pOffset->IsNumber()) - return FALSE; - - int shared_hint_table_offset = pOffset->GetInteger(); - CPDF_StreamAcc acc; - acc.LoadAllData(pHintStream); - - FX_DWORD size = acc.GetSize(); - // The header section of page offset hint table is 36 bytes. - // The header section of shared object hint table is 24 bytes. - // Hint table has at least 60 bytes. - const FX_DWORD MIN_STREAM_LEN = 60; - if (size < MIN_STREAM_LEN || shared_hint_table_offset <= 0 || - size < shared_hint_table_offset) { - return FALSE; - } - - CFX_BitStream bs; - bs.Init(acc.GetData(), size); - return ReadPageHintTable(&bs) && - ReadSharedObjHintTable(&bs, pdfium::base::checked_cast<FX_DWORD>( - shared_hint_table_offset)); -} - -int CPDF_HintTables::ReadPrimaryHintStreamOffset() const { - if (!m_pLinearizedDict) - return -1; - - CPDF_Array* pRange = m_pLinearizedDict->GetArrayBy("H"); - if (!pRange) - return -1; - - CPDF_Object* pStreamOffset = pRange->GetElementValue(0); - if (!pStreamOffset) - return -1; - - return pStreamOffset->GetInteger(); -} - -int CPDF_HintTables::ReadPrimaryHintStreamLength() const { - if (!m_pLinearizedDict) - return -1; - - CPDF_Array* pRange = m_pLinearizedDict->GetArrayBy("H"); - if (!pRange) - return -1; - - CPDF_Object* pStreamLen = pRange->GetElementValue(1); - if (!pStreamLen) - return -1; - - return pStreamLen->GetInteger(); -} |