diff options
| -rw-r--r-- | xmlsecurity/inc/pdfio/pdfdocument.hxx | 8 | ||||
| -rw-r--r-- | xmlsecurity/source/pdfio/pdfdocument.cxx | 175 |
2 files changed, 174 insertions, 9 deletions
diff --git a/xmlsecurity/inc/pdfio/pdfdocument.hxx b/xmlsecurity/inc/pdfio/pdfdocument.hxx index b02bf9322088..3886eab8e73a 100644 --- a/xmlsecurity/inc/pdfio/pdfdocument.hxx +++ b/xmlsecurity/inc/pdfio/pdfdocument.hxx @@ -37,7 +37,13 @@ public: virtual ~PDFElement() { } }; -/// In-memory representation of an on-disk PDF document. +/** + * In-memory representation of an on-disk PDF document. + * + * The PDF element list is not meant to be saved back to disk, but some + * elements remember their source offset / length, and based on that it's + * possible to modify the input file. + */ class XMLSECURITY_DLLPUBLIC PDFDocument { /// This vector owns all elements. diff --git a/xmlsecurity/source/pdfio/pdfdocument.cxx b/xmlsecurity/source/pdfio/pdfdocument.cxx index 947bacb78f13..5778f202f835 100644 --- a/xmlsecurity/source/pdfio/pdfdocument.cxx +++ b/xmlsecurity/source/pdfio/pdfdocument.cxx @@ -59,11 +59,18 @@ public: /// Numbering object: an integer or a real. class PDFNumberElement : public PDFElement { + /// Input file start location. + sal_uInt64 m_nOffset; + /// Input file token length. + sal_uInt64 m_nLength; double m_fValue; public: + PDFNumberElement(); bool Read(SvStream& rStream) override; double GetValue() const; + sal_uInt64 GetLocation() const; + sal_uInt64 GetLength() const; }; class PDFReferenceElement; @@ -79,6 +86,10 @@ class PDFObjectElement : public PDFElement sal_uInt64 m_nDictionaryOffset; /// Length of the dictionary buffer till (before) the '<<' token. sal_uInt64 m_nDictionaryLength; + /// Position after the '/' token. + std::map<OString, sal_uInt64> m_aDictionaryKeyOffset; + /// Length of the dictionary key and value, till (before) the next token. + std::map<OString, sal_uInt64> m_aDictionaryKeyValueLength; public: PDFObjectElement(PDFDocument& rDoc, double fObjectValue, double fGenerationValue); @@ -91,12 +102,16 @@ public: sal_uInt64 GetDictionaryOffset(); void SetDictionaryLength(sal_uInt64 nDictionaryLength); sal_uInt64 GetDictionaryLength(); + void SetDictionaryKeyOffset(const OString& rKey, sal_uInt64 nOffset); + sal_uInt64 GetDictionaryKeyOffset(const OString& rKey) const; + void SetDictionaryKeyValueLength(const OString& rKey, sal_uInt64 nLength); + sal_uInt64 GetDictionaryKeyValueLength(const OString& rKey) const; }; /// Dictionary object: a set key-value pairs. class PDFDictionaryElement : public PDFElement { - /// Offset after the '>>' token. + /// Offset after the '<<' token. sal_uInt64 m_nLocation; public: @@ -122,9 +137,16 @@ public: class PDFNameElement : public PDFElement { OString m_aValue; + /// Offset after the '/' token. + sal_uInt64 m_nLocation; + /// Length till the next token start. + sal_uInt64 m_nLength; public: + PDFNameElement(); bool Read(SvStream& rStream) override; const OString& GetValue() const; + sal_uInt64 GetLocation() const; + sal_uInt64 GetLength() const; }; /// Reference object: something with a unique ID. @@ -172,8 +194,11 @@ public: /// Array object: a list. class PDFArrayElement : public PDFElement { + /// Location after the '[' token. + sal_uInt64 m_nOffset; std::vector<PDFElement*> m_aElements; public: + PDFArrayElement(); bool Read(SvStream& rStream) override; void PushBack(PDFElement* pElement); const std::vector<PDFElement*>& GetElements(); @@ -182,8 +207,12 @@ public: /// End of an array: ']'. class PDFEndArrayElement : public PDFElement { + /// Location before the ']' token. + sal_uInt64 m_nOffset; public: + PDFEndArrayElement(); bool Read(SvStream& rStream) override; + sal_uInt64 GetOffset() const; }; /// Boolean object: a 'true' or a 'false'. @@ -355,11 +384,33 @@ bool PDFDocument::Sign(const uno::Reference<security::XCertificate>& xCertificat m_aEditBuffer.WriteUInt32AsString(nFirstPageId); m_aEditBuffer.WriteCharPtr(" 0 obj\n"); m_aEditBuffer.WriteCharPtr("<<"); - m_aEditBuffer.WriteBytes(static_cast<const char*>(m_aEditBuffer.GetData()) + pFirstPage->GetDictionaryOffset(), pFirstPage->GetDictionaryLength()); - m_aEditBuffer.WriteCharPtr("/Annots["); - m_aEditBuffer.WriteUInt32AsString(nAnnotId); - m_aEditBuffer.WriteCharPtr(" 0 R]"); - m_aEditBuffer.WriteCharPtr(">>\nendobj\n\n"); + auto pAnnots = dynamic_cast<PDFArrayElement*>(pFirstPage->Lookup("Annots")); + if (!pAnnots) + { + // No Annots key, just write the key with a single reference. + m_aEditBuffer.WriteBytes(static_cast<const char*>(m_aEditBuffer.GetData()) + pFirstPage->GetDictionaryOffset(), pFirstPage->GetDictionaryLength()); + m_aEditBuffer.WriteCharPtr("/Annots["); + m_aEditBuffer.WriteUInt32AsString(nAnnotId); + m_aEditBuffer.WriteCharPtr(" 0 R]"); + } + else + { + // Annots key is already there, insert our reference at the end. + + // Offset right before the end of the Annots array. + sal_uInt64 nAnnotsEndOffset = pFirstPage->GetDictionaryKeyOffset("Annots") + pFirstPage->GetDictionaryKeyValueLength("Annots") - 1; + // Length of beginning of the dictionary -> Annots end. + sal_uInt64 nAnnotsBeforeEndLength = nAnnotsEndOffset - pFirstPage->GetDictionaryOffset(); + m_aEditBuffer.WriteBytes(static_cast<const char*>(m_aEditBuffer.GetData()) + pFirstPage->GetDictionaryOffset(), nAnnotsBeforeEndLength); + m_aEditBuffer.WriteCharPtr(" "); + m_aEditBuffer.WriteUInt32AsString(nAnnotId); + m_aEditBuffer.WriteCharPtr(" 0 R"); + // Length of Annots end -> end of the dictionary. + sal_uInt64 nAnnotsAfterEndLength = pFirstPage->GetDictionaryOffset() + pFirstPage->GetDictionaryLength() - nAnnotsEndOffset; + m_aEditBuffer.WriteBytes(static_cast<const char*>(m_aEditBuffer.GetData()) + nAnnotsEndOffset, nAnnotsAfterEndLength); + } + m_aEditBuffer.WriteCharPtr(">>"); + m_aEditBuffer.WriteCharPtr("\nendobj\n\n"); // Write the updated Catalog object, references nAnnotId. auto pRoot = dynamic_cast<PDFReferenceElement*>(m_pTrailer->Lookup("Root")); @@ -1349,9 +1400,17 @@ bool PDFCommentElement::Read(SvStream& rStream) return false; } +PDFNumberElement::PDFNumberElement() + : m_nOffset(0), + m_nLength(0), + m_fValue(0) +{ +} + bool PDFNumberElement::Read(SvStream& rStream) { OStringBuffer aBuf; + m_nOffset = rStream.Tell(); char ch; rStream.ReadChar(ch); while (!rStream.IsEof()) @@ -1359,6 +1418,7 @@ bool PDFNumberElement::Read(SvStream& rStream) if (!isdigit(ch) && ch != '-') { rStream.SeekRel(-1); + m_nLength = rStream.Tell() - m_nOffset; m_fValue = aBuf.makeStringAndClear().toDouble(); SAL_INFO("xmlsecurity.pdfio", "PDFNumberElement::Read: m_fValue is '" << m_fValue << "'"); return true; @@ -1370,6 +1430,16 @@ bool PDFNumberElement::Read(SvStream& rStream) return false; } +sal_uInt64 PDFNumberElement::GetLocation() const +{ + return m_nOffset; +} + +sal_uInt64 PDFNumberElement::GetLength() const +{ + return m_nLength; +} + PDFBooleanElement::PDFBooleanElement(bool /*bValue*/) { } @@ -1506,6 +1576,7 @@ void PDFDictionaryElement::Parse(const std::vector< std::unique_ptr<PDFElement> } OString aName; + sal_uInt64 nNameOffset = 0; std::vector<PDFNumberElement*> aNumbers; // The array value we're in -- if any. PDFArrayElement* pArray = nullptr; @@ -1541,7 +1612,13 @@ void PDFDictionaryElement::Parse(const std::vector< std::unique_ptr<PDFElement> { if (!aNumbers.empty()) { - rDictionary[aName] = aNumbers.back(); + PDFNumberElement* pNumber = aNumbers.back(); + rDictionary[aName] = pNumber; + if (pThisObject) + { + pThisObject->SetDictionaryKeyOffset(aName, nNameOffset); + pThisObject->SetDictionaryKeyValueLength(aName, pNumber->GetLocation() + pNumber->GetLength() - nNameOffset); + } aName.clear(); aNumbers.clear(); } @@ -1550,11 +1627,17 @@ void PDFDictionaryElement::Parse(const std::vector< std::unique_ptr<PDFElement> { // Remember key. aName = pName->GetValue(); + nNameOffset = pName->GetLocation(); } else { // Name-name key-value. rDictionary[aName] = pName; + if (pThisObject) + { + pThisObject->SetDictionaryKeyOffset(aName, nNameOffset); + pThisObject->SetDictionaryKeyValueLength(aName, pName->GetLocation() + pName->GetLength() - nNameOffset); + } aName.clear(); } continue; @@ -1567,7 +1650,8 @@ void PDFDictionaryElement::Parse(const std::vector< std::unique_ptr<PDFElement> continue; } - if (pArray && dynamic_cast<PDFEndArrayElement*>(rElements[i].get())) + auto pEndArr = dynamic_cast<PDFEndArrayElement*>(rElements[i].get()); + if (pArray && pEndArr) { if (!aNumbers.empty()) { @@ -1576,6 +1660,12 @@ void PDFDictionaryElement::Parse(const std::vector< std::unique_ptr<PDFElement> aNumbers.clear(); } rDictionary[aName] = pArray; + if (pThisObject) + { + pThisObject->SetDictionaryKeyOffset(aName, nNameOffset); + // Include the ending ']' in the length of the key - (array)value pair length. + pThisObject->SetDictionaryKeyValueLength(aName, pEndArr->GetOffset() - nNameOffset + 1); + } aName.clear(); pArray = nullptr; continue; @@ -1587,6 +1677,8 @@ void PDFDictionaryElement::Parse(const std::vector< std::unique_ptr<PDFElement> if (!pArray) { rDictionary[aName] = pReference; + if (pThisObject) + pThisObject->SetDictionaryKeyOffset(aName, nNameOffset); aName.clear(); } else @@ -1601,6 +1693,8 @@ void PDFDictionaryElement::Parse(const std::vector< std::unique_ptr<PDFElement> if (pLiteralString) { rDictionary[aName] = pLiteralString; + if (pThisObject) + pThisObject->SetDictionaryKeyOffset(aName, nNameOffset); aName.clear(); continue; } @@ -1611,6 +1705,8 @@ void PDFDictionaryElement::Parse(const std::vector< std::unique_ptr<PDFElement> if (!pArray) { rDictionary[aName] = pHexString; + if (pThisObject) + pThisObject->SetDictionaryKeyOffset(aName, nNameOffset); aName.clear(); } else @@ -1633,6 +1729,8 @@ void PDFDictionaryElement::Parse(const std::vector< std::unique_ptr<PDFElement> if (!aNumbers.empty()) { rDictionary[aName] = aNumbers.back(); + if (pThisObject) + pThisObject->SetDictionaryKeyOffset(aName, nNameOffset); aName.clear(); aNumbers.clear(); } @@ -1690,6 +1788,34 @@ sal_uInt64 PDFObjectElement::GetDictionaryOffset() return m_nDictionaryOffset; } +void PDFObjectElement::SetDictionaryKeyOffset(const OString& rKey, sal_uInt64 nOffset) +{ + m_aDictionaryKeyOffset[rKey] = nOffset; +} + +void PDFObjectElement::SetDictionaryKeyValueLength(const OString& rKey, sal_uInt64 nLength) +{ + m_aDictionaryKeyValueLength[rKey] = nLength; +} + +sal_uInt64 PDFObjectElement::GetDictionaryKeyOffset(const OString& rKey) const +{ + auto it = m_aDictionaryKeyOffset.find(rKey); + if (it == m_aDictionaryKeyOffset.end()) + return 0; + + return it->second; +} + +sal_uInt64 PDFObjectElement::GetDictionaryKeyValueLength(const OString& rKey) const +{ + auto it = m_aDictionaryKeyValueLength.find(rKey); + if (it == m_aDictionaryKeyValueLength.end()) + return 0; + + return it->second; +} + void PDFObjectElement::SetDictionaryLength(sal_uInt64 nDictionaryLength) { m_nDictionaryLength = nDictionaryLength; @@ -1878,6 +2004,12 @@ bool PDFEndDictionaryElement::Read(SvStream& rStream) return true; } +PDFNameElement::PDFNameElement() + : m_nLocation(0), + m_nLength(0) +{ +} + bool PDFNameElement::Read(SvStream& rStream) { char ch; @@ -1887,6 +2019,7 @@ bool PDFNameElement::Read(SvStream& rStream) SAL_WARN("xmlsecurity.pdfio", "PDFNameElement::Read: unexpected character: " << ch); return false; } + m_nLocation = rStream.Tell(); if (rStream.IsEof()) { @@ -1918,6 +2051,16 @@ const OString& PDFNameElement::GetValue() const return m_aValue; } +sal_uInt64 PDFNameElement::GetLocation() const +{ + return m_nLocation; +} + +sal_uInt64 PDFNameElement::GetLength() const +{ + return m_nLength; +} + PDFStreamElement::PDFStreamElement(size_t nLength) : m_nLength(nLength) { @@ -1941,6 +2084,11 @@ bool PDFEndObjectElement::Read(SvStream& /*rStream*/) return true; } +PDFArrayElement::PDFArrayElement() + : m_nOffset(0) +{ +} + bool PDFArrayElement::Read(SvStream& rStream) { char ch; @@ -1950,6 +2098,7 @@ bool PDFArrayElement::Read(SvStream& rStream) SAL_WARN("xmlsecurity.pdfio", "PDFArrayElement::Read: unexpected character: " << ch); return false; } + m_nOffset = rStream.Tell(); SAL_INFO("xmlsecurity.pdfio", "PDFArrayElement::Read: '['"); @@ -1966,8 +2115,14 @@ const std::vector<PDFElement*>& PDFArrayElement::GetElements() return m_aElements; } +PDFEndArrayElement::PDFEndArrayElement() + : m_nOffset(0) +{ +} + bool PDFEndArrayElement::Read(SvStream& rStream) { + m_nOffset = rStream.Tell(); char ch; rStream.ReadChar(ch); if (ch != ']') @@ -1981,6 +2136,10 @@ bool PDFEndArrayElement::Read(SvStream& rStream) return true; } +sal_uInt64 PDFEndArrayElement::GetOffset() const +{ + return m_nOffset; +} } // namespace pdfio } // namespace xmlsecurity |