vcl: add initial CppunitTest_vcl_pdfexport

Invoke the PDF export filter and then use the PDF tokenizer from
xmlsecurity to assert the contents of created PDF file. The testcase
fails with commit 6db0f1feb1d9931d2726dd11a889c58815710ce0 (tdf#106059
PDF export: create a reference XObject for PDF images, 2017-02-22)
reverted.

Change-Id: I90526fef41d9560ae447f586df766bc50a491c43
Reviewed-on: https://gerrit.libreoffice.org/34609
Reviewed-by: Miklos Vajna <vmiklos@collabora.co.uk>
Tested-by: Jenkins <ci@libreoffice.org>

2 files changed, 301 insertions, 0 deletions

diff --git a/include/xmlsecurity/pdfio/pdfdocument.hxx b/include/xmlsecurity/pdfio/pdfdocument.hxx
new file mode 100644
index 000000000000..0b27014c7418
--- /dev/null
+++ b/include/xmlsecurity/pdfio/pdfdocument.hxx
@@ -0,0 +1,278 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * 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 INCLUDED_XMLSECURITY_PDFIO_PDFDOCUMENT_HXX
+#define INCLUDED_XMLSECURITY_PDFIO_PDFDOCUMENT_HXX
+
+#include <map>
+#include <vector>
+
+#include <com/sun/star/security/XCertificate.hpp>
+
+#include <tools/stream.hxx>
+
+#include <xmlsecurity/xmlsecuritydllapi.h>
+
+struct SignatureInformation;
+
+namespace xmlsecurity
+{
+namespace pdfio
+{
+
+class PDFTrailerElement;
+class PDFHexStringElement;
+class PDFReferenceElement;
+class PDFDocument;
+class PDFDictionaryElement;
+class PDFArrayElement;
+class PDFStreamElement;
+
+/// A byte range in a PDF file.
+class XMLSECURITY_DLLPUBLIC PDFElement
+{
+public:
+    virtual bool Read(SvStream& rStream) = 0;
+    virtual ~PDFElement() { }
+};
+
+/// Indirect object: something with a unique ID.
+class XMLSECURITY_DLLPUBLIC PDFObjectElement : public PDFElement
+{
+    PDFDocument& m_rDoc;
+    double m_fObjectValue;
+    double m_fGenerationValue;
+    std::map<OString, PDFElement*> m_aDictionary;
+    /// Position after the '<<' token.
+    sal_uInt64 m_nDictionaryOffset;
+    /// Length of the dictionary buffer till (before) the '<<' token.
+    sal_uInt64 m_nDictionaryLength;
+    PDFDictionaryElement* m_pDictionaryElement;
+    /// The contained direct array, if any.
+    PDFArrayElement* m_pArrayElement;
+    /// The stream of this object, used when this is an object stream.
+    PDFStreamElement* m_pStreamElement;
+    /// Objects of an object stream.
+    std::vector< std::unique_ptr<PDFObjectElement> > m_aStoredElements;
+    /// Elements of an object in an object stream.
+    std::vector< std::unique_ptr<PDFElement> > m_aElements;
+    /// Uncompressed buffer of an object in an object stream.
+    std::unique_ptr<SvMemoryStream> m_pStreamBuffer;
+
+public:
+    PDFObjectElement(PDFDocument& rDoc, double fObjectValue, double fGenerationValue);
+    bool Read(SvStream& rStream) override;
+    PDFElement* Lookup(const OString& rDictionaryKey);
+    PDFObjectElement* LookupObject(const OString& rDictionaryKey);
+    double GetObjectValue() const;
+    void SetDictionaryOffset(sal_uInt64 nDictionaryOffset);
+    sal_uInt64 GetDictionaryOffset();
+    void SetDictionaryLength(sal_uInt64 nDictionaryLength);
+    sal_uInt64 GetDictionaryLength();
+    PDFDictionaryElement* GetDictionary() const;
+    void SetDictionary(PDFDictionaryElement* pDictionaryElement);
+    void SetArray(PDFArrayElement* pArrayElement);
+    void SetStream(PDFStreamElement* pStreamElement);
+    PDFArrayElement* GetArray() const;
+    /// Parse objects stored in this object stream.
+    void ParseStoredObjects();
+    std::vector< std::unique_ptr<PDFElement> >& GetStoredElements();
+    SvMemoryStream* GetStreamBuffer() const;
+    void SetStreamBuffer(std::unique_ptr<SvMemoryStream>& pStreamBuffer);
+};
+
+/// Name object: a key string.
+class XMLSECURITY_DLLPUBLIC 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;
+};
+
+/// Dictionary object: a set key-value pairs.
+class XMLSECURITY_DLLPUBLIC PDFDictionaryElement : public PDFElement
+{
+    /// Key-value pairs when the dictionary is a nested value.
+    std::map<OString, PDFElement*> m_aItems;
+    /// Offset after the '<<' token.
+    sal_uInt64 m_nLocation = 0;
+    /// 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:
+    PDFDictionaryElement();
+    bool Read(SvStream& rStream) override;
+
+    static size_t Parse(const std::vector< std::unique_ptr<PDFElement> >& rElements, PDFElement* pThis, std::map<OString, PDFElement*>& rDictionary);
+    static PDFElement* Lookup(const std::map<OString, PDFElement*>& rDictionary, const OString& rKey);
+    void SetKeyOffset(const OString& rKey, sal_uInt64 nOffset);
+    sal_uInt64 GetKeyOffset(const OString& rKey) const;
+    void SetKeyValueLength(const OString& rKey, sal_uInt64 nLength);
+    sal_uInt64 GetKeyValueLength(const OString& rKey) const;
+    const std::map<OString, PDFElement*>& GetItems() const;
+    /// Looks up an object which is only referenced in this dictionary.
+    PDFObjectElement* LookupObject(const OString& rDictionaryKey);
+};
+
+enum class TokenizeMode
+{
+    /// Full file.
+    END_OF_STREAM,
+    /// Till the first %%EOF token.
+    EOF_TOKEN,
+    /// Till the end of the current object.
+    END_OF_OBJECT,
+    /// Same as END_OF_OBJECT, but for object streams (no endobj keyword).
+    STORED_OBJECT
+};
+
+/// The type column of an entry in a cross-reference stream.
+enum class XRefEntryType
+{
+    /// xref "f" or xref stream "0".
+    FREE,
+    /// xref "n" or xref stream "1".
+    NOT_COMPRESSED,
+    /// xref stream "2.
+    COMPRESSED
+};
+
+/// An entry in a cross-reference stream.
+struct XRefEntry
+{
+    XRefEntryType m_eType;
+    /**
+     * Non-compressed: The byte offset of the object, starting from the
+     * beginning of the file.
+     * Compressed: The object number of the object stream in which this object is
+     * stored.
+     */
+    sal_uInt64 m_nOffset;
+    /**
+     * Non-compressed: The generation number of the object.
+     * Compressed: The index of this object within the object stream.
+     */
+    sal_uInt64 m_nGenerationNumber;
+    /// Are changed as part of an incremental update?.
+    bool m_bDirty;
+
+    XRefEntry();
+};
+
+/**
+ * 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.
+    std::vector< std::unique_ptr<PDFElement> > m_aElements;
+    /// Object ID <-> object offset map.
+    std::map<size_t, XRefEntry> m_aXRef;
+    /// Object offset <-> Object pointer map.
+    std::map<size_t, PDFObjectElement*> m_aOffsetObjects;
+    /// Object ID <-> Object pointer map.
+    std::map<size_t, PDFObjectElement*> m_aIDObjects;
+    /// List of xref offsets we know.
+    std::vector<size_t> m_aStartXRefs;
+    /// List of EOF offsets we know.
+    std::vector<size_t> m_aEOFs;
+    PDFTrailerElement* m_pTrailer;
+    /// When m_pTrailer is nullptr, this can still have a dictionary.
+    PDFObjectElement* m_pXRefStream;
+    /// All editing takes place in this buffer, if it happens.
+    SvMemoryStream m_aEditBuffer;
+
+    static int AsHex(char ch);
+    /// Decode a hex dump.
+    static std::vector<unsigned char> DecodeHexString(PDFHexStringElement* pElement);
+    /// Suggest a minimal, yet free signature ID to use for the next signature.
+    sal_uInt32 GetNextSignature();
+    /// Write the signature object as part of signing.
+    sal_Int32 WriteSignatureObject(const OUString& rDescription, bool bAdES, sal_uInt64& rLastByteRangeOffset, sal_Int64& rSignatureContentOffset);
+    /// Write the appearance object as part of signing.
+    sal_Int32 WriteAppearanceObject();
+    /// Write the annot object as part of signing.
+    sal_Int32 WriteAnnotObject(PDFObjectElement& rFirstPage, sal_Int32 nSignatureId, sal_Int32 nAppearanceId);
+    /// Write the updated Page object as part of signing.
+    bool WritePageObject(PDFObjectElement& rFirstPage, sal_Int32 nAnnotId);
+    /// Write the updated Catalog object as part of signing.
+    bool WriteCatalogObject(sal_Int32 nAnnotId, PDFReferenceElement*& pRoot);
+    /// Write the updated cross-references as part of signing.
+    void WriteXRef(sal_uInt64 nXRefOffset, PDFReferenceElement* pRoot);
+
+public:
+    PDFDocument();
+    PDFDocument& operator=(const PDFDocument&) = delete;
+    PDFDocument(const PDFDocument&) = delete;
+    /// @name Low-level functions, to be used by PDFElement subclasses.
+    //@{
+    static OString ReadKeyword(SvStream& rStream);
+    static size_t FindStartXRef(SvStream& rStream);
+    void ReadXRef(SvStream& rStream);
+    void ReadXRefStream(SvStream& rStream);
+    static void SkipWhitespace(SvStream& rStream);
+    /// Instead of all whitespace, just skip CR and NL characters.
+    static void SkipLineBreaks(SvStream& rStream);
+    size_t GetObjectOffset(size_t nIndex) const;
+    const std::vector< std::unique_ptr<PDFElement> >& GetElements();
+    std::vector<PDFObjectElement*> GetPages();
+    /// Remember the end location of an EOF token.
+    void PushBackEOF(size_t nOffset);
+    /// Look up object based on object number, possibly by parsing object streams.
+    PDFObjectElement* LookupObject(size_t nObjectNumber);
+    /// Access to the input document, even after the input stream is gone.
+    SvMemoryStream& GetEditBuffer();
+    /// Tokenize elements from current offset.
+    bool Tokenize(SvStream& rStream, TokenizeMode eMode, std::vector< std::unique_ptr<PDFElement> >& rElements, PDFObjectElement* pObject);
+    /// Register an object (owned directly or indirectly by m_aElements) as a provider for a given ID.
+    void SetIDObject(size_t nID, PDFObjectElement* pObject);
+    //@}
+
+    /// @name High-level functions, to be used by others.
+    //@{
+    /// Read elements from the start of the stream till its end.
+    bool Read(SvStream& rStream);
+    /// Sign the read document with xCertificate in the edit buffer.
+    bool Sign(const css::uno::Reference<css::security::XCertificate>& xCertificate, const OUString& rDescription, bool bAdES);
+    /// Serializes the contents of the edit buffer.
+    bool Write(SvStream& rStream);
+    /// Get a list of signatures embedded into this document.
+    std::vector<PDFObjectElement*> GetSignatureWidgets();
+    /**
+     * @param rInformation The actual result.
+     * @param bLast If this is the last signature in the file, so it covers the whole file physically.
+     * @return If we can determinate a result.
+     */
+    static bool ValidateSignature(SvStream& rStream, PDFObjectElement* pSignature, SignatureInformation& rInformation, bool bLast);
+    /// Remove the nth signature from read document in the edit buffer.
+    bool RemoveSignature(size_t nPosition);
+    //@}
+};
+
+} // namespace pdfio
+} // namespace xmlsecurity
+
+#endif // INCLUDED_XMLSECURITY_PDFIO_PDFDOCUMENT_HXX
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/include/xmlsecurity/xmlsecuritydllapi.h b/include/xmlsecurity/xmlsecuritydllapi.h
new file mode 100644
index 000000000000..48da5464b727
--- /dev/null
+++ b/include/xmlsecurity/xmlsecuritydllapi.h
@@ -0,0 +1,23 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * 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 INCLUDED_XMLSECURITY_XMLSECURITYDLLAPI_H
+#define INCLUDED_XMLSECURITY_XMLSECURITYDLLAPI_H
+
+#include <sal/types.h>
+
+#if defined(XMLSECURITY_DLLIMPLEMENTATION)
+#define XMLSECURITY_DLLPUBLIC SAL_DLLPUBLIC_EXPORT
+#else
+#define XMLSECURITY_DLLPUBLIC SAL_DLLPUBLIC_IMPORT
+#endif
+
+#endif // INCLUDED_XMLSECURITY_XMLSECURITYDLLAPI_H
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */