/* * Copyright (c) 2022, Matthew Olsson <mattco@serenityos.org> * * SPDX-License-Identifier: BSD-2-Clause */ #pragma once #include <AK/Span.h> #include <LibPDF/ObjectDerivatives.h> namespace PDF { class SecurityHandler : public RefCounted<SecurityHandler> { public: static PDFErrorOr<NonnullRefPtr<SecurityHandler>> create(Document*, NonnullRefPtr<DictObject> encryption_dict); virtual ~SecurityHandler() = default; virtual bool try_provide_user_password(StringView password) = 0; virtual bool has_user_password() const = 0; virtual void encrypt(NonnullRefPtr<Object>, Reference reference) const = 0; virtual void decrypt(NonnullRefPtr<Object>, Reference reference) const = 0; }; class StandardSecurityHandler : public SecurityHandler { public: static PDFErrorOr<NonnullRefPtr<StandardSecurityHandler>> create(Document*, NonnullRefPtr<DictObject> encryption_dict); StandardSecurityHandler(Document*, size_t revision, DeprecatedString const& o_entry, DeprecatedString const& u_entry, u32 flags, bool encrypt_metadata, size_t length); ~StandardSecurityHandler() override = default; bool try_provide_user_password(StringView password_string) override; bool has_user_password() const override { return m_encryption_key.has_value(); } protected: void encrypt(NonnullRefPtr<Object>, Reference reference) const override; void decrypt(NonnullRefPtr<Object>, Reference reference) const override; private: template<bool is_revision_2> ByteBuffer compute_user_password_value(ByteBuffer password_string); ByteBuffer compute_encryption_key(ByteBuffer password_string); Document* m_document; size_t m_revision; Optional<ByteBuffer> m_encryption_key; DeprecatedString m_o_entry; DeprecatedString m_u_entry; u32 m_flags; bool m_encrypt_metadata; size_t m_length; }; class RC4 { public: RC4(ReadonlyBytes key); void generate_bytes(ByteBuffer&); ByteBuffer encrypt(ReadonlyBytes bytes); private: Array<size_t, 256> m_bytes; }; }