PdfSignature.h

// SPDX-FileCopyrightText: 2011 Dominik Seichter <domseichter@web.de>
// SPDX-FileCopyrightText: 2011 Petr Pytelka
// SPDX-FileCopyrightText: 2020 Francesco Pretto <ceztko@gmail.com>
// SPDX-License-Identifier: LGPL-2.0-or-later OR MPL-2.0
 
#ifndef PDF_SIGNATURE_H
#define PDF_SIGNATURE_H
 
#include "PdfDeclarations.h"
 
#include "PdfAnnotation.h"
#include "PdfField.h"
#include "PdfDate.h"
#include "PdfData.h"
#include <podofo/auxiliary/InputDevice.h>
#include <podofo/auxiliary/OutputDevice.h>
 
namespace PoDoFo {
 
class PdfAcroForm;
 
enum class PdfCertPermission : uint8_t
{
    NoPerms = 1,
    FormFill = 2,
    Annotations = 3,
};
 
struct PdfSignatureBeacons final
{
    PdfSignatureBeacons();
    charbuff ContentsBeacon;
    charbuff ByteRangeBeacon;
    std::shared_ptr<size_t> ContentsOffset;
    std::shared_ptr<size_t> ByteRangeOffset;
};
 
enum class PdfSignatureVerifyStatus : uint8_t
{
    Indeterminate = 0,
 
    Invalid,
 
    CryptoVerifiedPartialCoverage,
 
    CryptoVerified,
};
 
class PODOFO_API PdfSignature final : public PdfField
{
    friend class PdfField;
    friend class PdfSigningContext;
    friend class PdfDocument;
 
private:
    PdfSignature(PdfAcroForm& acroform, std::shared_ptr<PdfField>&& parent);
 
    PdfSignature(PdfAnnotationWidget& widget, std::shared_ptr<PdfField>&& parent);
 
    PdfSignature(PdfObject& obj, PdfAcroForm* acroform);
 
public:
    bool TryVerifySignature(InputStreamDevice& input, PdfSignatureVerifyStatus& status) const;
 
    void SetSignerName(nullable<const PdfString&> text);
 
    void SetSignatureReason(nullable<const PdfString&> text);
 
    void SetSignatureLocation(nullable<const PdfString&> text);
 
    [[deprecated("Use the SetCreatingApplication method instead")]]
    void SetSignatureCreator(nullable<const PdfString&> creator);
 
    void SetCreatingApplication(nullable<const PdfName&> application);
 
    void SetSignatureDate(nullable<const PdfDate&> sigDate);
 
    void AddCertificationReference(PdfCertPermission perm = PdfCertPermission::NoPerms);
 
    nullable<const PdfString&> GetSignerName() const;
 
    nullable<const PdfString&> GetSignatureReason() const;
 
    nullable<const PdfString&> GetSignatureLocation() const;
 
    nullable<PdfDate> GetSignatureDate() const;
 
    void EnsureValueObject();
 
    PdfSignature* GetParent();
    const PdfSignature* GetParent() const;
 
    bool TryGetPreviousRevision(InputStreamDevice& input, OutputStreamDevice& output) const;
 
protected:
    PdfObject* getValueObject() const override;
 
private:
    void PrepareForSigning(const std::string_view& filter,
        const std::string_view& subFilter,
        const std::string_view& type,
        const PdfSignatureBeacons& beacons);
 
    // To be called by SignDocument()
    void SetContentsByteRangeNoDirtySet(const bufferview& contents, PdfArray&& byteRange);
 
    // To be called by PdfDocument
    nullable<std::array<size_t, 4>> GetByteRangeBounds() const;
 
    void ensureValueObject();
private:
    void init(PdfAcroForm& acroForm);
 
private:
    PdfObject* m_ValueObj;
};
 
}
 
#endif // PDF_SIGNATURE_H