sec_clr.h

伯克利做的SFTP安全文件传输协议

// sec_clr.h
// cleartext "security" mechanism
// copyright SafeTP Development Group, Inc., 2000  Terms of use are as specified in license.txt

#ifndef __SEC_CLR_H
#define __SEC_CLR_H

#include "provider.h"     // SecurityProvider, *Security

// ----------------- X-Cleartext ---------------------
// simple identity encoding and decoding
class CleartextControlSecurity : public ControlSecurity {
public:
  // Transform functions
  virtual int maximumEncodedSize(int decodedSize) const
    { return decodedSize; }
  virtual int maximumDecodedSize(int encodedSize) const
    { return encodedSize; }

  virtual void encode(DataBlock &) {}
  virtual void decode(DataBlock &) {}

  // ControlSecurity functions
  // (none; no ADAT)
};


// identity encode/decode
class CleartextDataSecurity : public DataSecurity {
public:
  // Transform functions
  virtual int maximumEncodedSize(int decodedSize) const
    { return decodedSize; }
  virtual int maximumDecodedSize(int encodedSize) const
    { return encodedSize; }

  virtual void encode(DataBlock &) {}
  virtual void decode(DataBlock &) {}

  // DataSecurity functions
  virtual DataSecurityLevel getSupportedProtLevels() const;
  virtual char getCodeForLevel(DataSecurityLevel level) const;
  virtual DataSecurityLevel getLevelForCode(char code) const;
};


// simplest possible "security" mechanism: X-Cleartext
class CleartextProvider : public SecurityProvider {
  CleartextControlSecurity _control;
  CleartextDataSecurity _data;

public:
  virtual ControlSecurity &control()
    { return _control; }
  virtual DataSecurity &data()
    { return _data; }
};


// ----------------- X-Cleartext2 ---------------------
// cleartext mechanism with some ADAT exchanges, for debugging
class CleartextControl2 : public CleartextControlSecurity {
private:            // data
  bool isClient;
  int state;

  static char const * const serverFirst;
  static char const * const clientFirst;
  static char const * const serverSecond;
  static char const * const clientSecond;

private:            // funcs
  void checkAdat(DataBlock const &reallyIs, char const *shouldBe,
                 char const *context);

public:
  CleartextControl2(bool ic) : isClient(ic), state(0) {}

  virtual bool hasOutgoingAdat() const;
  virtual void getNextOutgoingAdat(DataBlock &block);

  virtual bool expectingIncomingAdat() const;
  virtual void incomingAdat(DataBlock &block);
};


// provider for X-Cleartext2
class CleartextProvider2 : public SecurityProvider {
  CleartextControl2 _control;
  CleartextDataSecurity _data;

public:
  CleartextProvider2(bool ic)
    : _control(ic), _data() {}

  virtual ControlSecurity &control()
    { return _control; }
  virtual DataSecurity &data()
    { return _data; }
};

#endif // __SEC_CLR_H