reply.h

伯克利做的SFTP安全文件传输协议

// reply.h
// Reply class, holds FTP replies
// copyright SafeTP Development Group, Inc., 2000  Terms of use are as specified in license.txt

#ifndef __REPLY_H
#define __REPLY_H

#include "str.h"           // string
#include "exc.h"           // xBase

#ifndef SAFETPC
#include "socketd.h"       // SOCKET

class StreamLineReader;    // see lineread.h
#endif

// first digit of reply codes
enum ReplyCodeFirst {
  RCF_POSITIVE_PRELIMINARY=100,
  RCF_POSITIVE_COMPLETION=200,
  RCF_POSITIVE_INTERMEDIATE=300,
  RCF_NEGATIVE_TRANSIENT=400,
  RCF_NEGATIVE_PERMANENT=500,
  RCF_ENCRYPTED=600
};

bool valid(ReplyCodeFirst f);


// second digit of reply codes
enum ReplyCodeSecond {
  RCS_SYNTAX=0,
  RCS_INFORMATION=10,
  RCS_CONNECTION=20,
  RCS_AUTHENTICATION=30,
  RCS_UNSPECIFIED=40,
  RCS_FILE_SYSTEM=50
};

bool valid(ReplyCodeSecond s);


// third digit of reply codes (no orthogonal semantics)
enum ReplyCodeThird {
  RCT_0, RCT_1, RCT_2, RCT_3, RCT_4, RCT_5, RCT_6, RCT_7, RCT_8, RCT_9,
};

bool valid(ReplyCodeThird t);


// complete codes as defined by 959 and 2228
enum ReplyCode {
  // code ranges
  RC_MINIMUM = 100,
  RC_MAXIMUM = 659,

  // 959 codes
  RC_RESTART_MARKER_REPLY=110,
  RC_SERVICE_READY_SOON=120,
  RC_DATA_CONN_ALREADY_OPEN=125,
  RC_FILE_STATUS_OK=150,

  RC_COMMAND_OK=200,
  RC_COMMAND_SUPERFLUOUS=202,
  RC_SYSTEM_STATUS=211,
  RC_DIRECTORY_STATUS=212,
  RC_FILE_STATUS=213,
  RC_HELP_MESSAGE=214,
  RC_NAME_SYSTEM_TYPE=215,
  RC_SERVICE_READY=220,
  RC_SERVICE_CLOSING=221,
  RC_DATA_CONN_OPEN=225,
  RC_CONN_ACTION_SUCCESSFUL=226,
  RC_ENTERING_PASSIVE=227,
  RC_USER_LOGGED_IN=230,
  RC_FILE_ACTION_SUCCESSFUL=250,
  RC_PATHNAME_CREATED=257,

  RC_NEED_PASSWORD=331,
  RC_NEED_ACCOUNT=332,
  RC_FILE_ACTION_NEED_INFO=350,

  RC_SERVICE_NOT_AVAILABLE=421,
  RC_FAILED_DATA_CONN_OPEN=425,
  RC_TRANSFER_ABORTED=426,
  RC_FILE_TEMPORARILY_UNAVAILABLE=450,
  RC_FILE_ACTION_ERROR=451,
  RC_FILE_ACTION_INSUFFICIENT_STORAGE=452,

  RC_UNRECOGNIZED_COMMAND=500,
  RC_PARAMETER_SYNTAX_ERROR=501,
  RC_COMMAND_NOT_IMPLEMENTED=502,
  RC_BAD_COMMAND_SEQUENCE=503,
  RC_PARAMETER_NOT_IMPLEMENTED=504,
  RC_NOT_LOGGED_IN=530,
  RC_FILE_NEED_ACCOUNT=532,
  RC_FILE_UNAVAILABLE=550,
  RC_FILE_PAGE_TYPE_UNKNOWN=551,
  RC_FILE_ACTION_QUOTA_EXCEEDED=552,
  RC_FILE_NAME_NOT_ALLOWED=553,

  // 2228 replies
  RC_AUTHORIZED_USER_LOGGED_IN=232,
  RC_SECURITY_DATA_EXCHANGE_COMPLETE=234,
  RC_LAST_ADAT=235,

  RC_FIRST_ADAT=334,
  RC_MIDDLE_ADAT=335,
  RC_PASSWORD_CHALLENGE=336,

  RC_SECURITY_RESOURCE_UNAVAILABLE=431,

  RC_PROTECTION_LEVEL_DENIED=533,
  RC_REQUEST_DENIED=534,
  RC_FAILED_SECURITY_CHECK=535,
  RC_UNSUPPORTED_PROT_LEVEL=536,
  RC_UNSUPPORTED_COMMAND_PROTECTION=537,

  RC_INTEGRITY=631,
  RC_PRIVATE_INTEGRITY=632,
  RC_PRIVATE=633,

  // reply codes that we added, as documented in our internet draft
  RC_PBSZ_TOO_SMALL=538,

  // replies I added
  RC_INTERNAL_ERROR=510,      // ideally, we'll never send this.. if we do,
                              // it is technically a violation of 959

  // last one, so line doesn't end with a comma
  __last_one_dont_use
};

bool valid(ReplyCode c);


// simple reply code extraction and composition,
// guaranteed to only return valid values (exception otherwise)
ReplyCodeFirst first(ReplyCode code);
ReplyCodeSecond second(ReplyCode code);
ReplyCodeThird third(ReplyCode code);

// checks for valid argument ranges (exception otherwise)
ReplyCode makeCode(ReplyCodeFirst f, ReplyCodeSecond s, ReplyCodeThird t);


// returns true when s begins with a three-digit
// reply code, and either legal separator
bool replyCodeStart(char const *s);


// holds a complete (possibly multiline) reply from server
class Reply {
private:     // types
  typedef string (*LineGetter)(void *&arg);

public:      // types
  // constants
  enum {
    ADATTagLen = 5     // length of "ADAT="
  };

private:     // data
  // lines of text
  string **text;           // array of string pointers
  int numLines;            // # lines defined
  int arraySize;           // allocated size of array

  ReplyCode code;          // the (3-digit) reply code
    // note that this code is not necessarily among those defined above

  // TODO: Add something to store the complete reply as it came over the
  //       wire, for correct DIGT calculation with non-canonical replies. 

private:     // funcs
  static string socketLineGetter(void *&arg);
  static string bufferLineGetter(void *&arg);
#ifndef SAFETPC
  static string streamLineGetter(void *&arg);
#endif

  void parse(LineGetter getter, void *&arg);

  void init();
  string **alloc(int size);

public:      // funcs
  // copy ctor
  Reply(Reply const &obj);

  // ----- composing ctors -------
  // construct a one-line reply
  Reply(ReplyCode replyCode, char const *firstLine);

  // ----- parsing ctors ------
  // read and parse next reply
  Reply(SOCKET s);

  // parse from in-memory buffer; this is actually fairly complicated,
  // see the comments near the code
  Reply(char const *&text);

  // parse from arbitrary stream source
#ifndef SAFETPC
  Reply(StreamLineReader &reader);
#endif

  // free mem
  ~Reply();

  // append a line of text
  void append(char const *s);

  // send reply to a socket
  void send(SOCKET s) const;

  // get the reply code; note that ReplyCode only defines symbolic
  // constants for a subset of all possible 3-letter replies
  ReplyCode getCode() const { return code; }

  // get the entire reply as CRLF-separated lines, terminated by CRLF,
  // and with each line starting with the reply code
  string getAllText() const;

  // retrieve individual lines
  int getNumLines() const { return numLines; }
  string getNthLine(int n) const;    // 0-based index

  // retrieve last line of text (no CRLF at end)
  string getLastText() const;

  // get the entire reply text as a single line, with no reply codes
  // or newlines anywhere in the string
  string getAllTextAsOneLine() const;

  // convenient test: true if the reply contains authentication data
  bool containsADAT() const;
};


// exception class to signal a negative reply
class xReply : public xBase {
public:
  ReplyCode code;    // numeric code
  string text;       // server's text (does *not* include the code)

public:
  xReply(ReplyCode code, char const *text);
  xReply(Reply const &reply);
  xReply(xReply const &obj);
  ~xReply();
};

#endif // __REPLY_H