FTPD(1M)                                                 FTPD(1M)



     NAME
          ftpd - DARPA Internet File Transfer Protocol server

     SYNOPSIS
          /etc/ftpd [ -d ] [ -l ] [ -ttimeout ]

     DESCRIPTION
          Ftpd is the DARPA Internet File Transfer Prototocol server
          process.  The server uses the TCP protocol and listens at
          the port specified in the ``ftp'' service specification; see
          services(4).

          If the -d option is specified, debugging information is
          written to the syslog.

          If the -l option is specified, each ftp session is logged in
          the syslog.

          The ftp server will timeout an inactive session after 15
          minutes.  If the -t option is specified, the inactivity
          timeout period will be set to timeout.

          The ftp server currently supports the following ftp
          requests;  case is not distinguished.

          Request        Description
          ABOR           abort previous command
          ACCT           specify account (ignored)
          ALLO           allocate storage (vacuously)
          APPE           append to a file
          CDUP           change to parent of current working directory
          CWD            change working directory
          DELE           delete a file
          HELP           give help information
          LIST           give list files in a directory (``ls -lg'')
          MKD            make a directory
          MODE           specify data transfer mode
          NLST           give name list of files in directory (``ls'')
          NOOP           do nothing
          PASS           specify password
          PASV           prepare for server-to-server transfer
          PORT           specify data connection port
          PWD            print the current working directory
          QUIT           terminate session
          RETR           retrieve a file
          RMD            remove a directory
          RNFR           specify rename-from file name
          RNTO           specify rename-to file name
          STOR           store a file
          STOU           store a file with a unique name
          STRU           specify data transfer structure
          TYPE           specify data transfer type



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     FTPD(1M)                                                 FTPD(1M)



          USER           specify user name
          XCUP           change to parent of current working directory
          XCWD           change working directory
          XMKD           make a directory
          XPWD           print the current working directory
          XRMD           remove a directory

          The remaining ftp requests specified in Internet RFC 959 are
          recognized, but not implemented.

          The ftp server will abort an active file transfer only when
          the ABOR command is preceded by a Telnet "Interrupt Process"
          (IP) signal and a Telnet "Synch" signal in the command
          Telnet stream, as described in Internet RFC 959.

          Ftpd interprets file names according to the ``globbing''
          conventions used by csh(1).  This allows users to utilize
          the metacharacters ``*?[]{}~''.

          Ftpd authenticates users according to three rules.

          1)   The user name must be in the password data base,
               /etc/passwd, and not have a null password.  In this
               case a password must be provided by the client before
               any file operations may be performed.

          2)   The user name must not appear in the file
               /etc/ftpusers.

          3)   The user must have a standard shell returned by
               getusershell(3).

          4)   If the user name is ``anonymous'' or ``ftp'', an
               anonymous ftp account must be present in the password
               file (user ``ftp'').  In this case the user is allowed
               to log in by specifying any password (by convention
               this is given as the client host's name).

          In the last case, ftpd takes special measures to restrict
          the client's access privileges.  The server performs a
          chroot(2) command to the home directory of the ``ftp'' user.
          In order that system security is not breached, it is
          recommended that the ``ftp'' subtree be constructed with
          care;  the following rules are recommended.

          ~ftp)
               Make the home directory owned by ``ftp'' and unwritable
               by anyone.

          ~ftp/bin)
               Make this directory owned by the super-user and
               unwritable by anyone.  The program ls(1) must be



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     FTPD(1M)                                                 FTPD(1M)



               present to support the list commands.  This program
               should have mode 111.

          ~ftp/etc)
               Make this directory owned by the super-user and
               unwritable by anyone.  The files passwd(5) and group(5)
               must be present for the ls command to work properly.
               These files should be mode 444.

          ~ftp/pub)
               Make this directory mode 777 and owned by ``ftp''.
               Users should then place files which are to be
               accessible via the anonymous account in this directory.

     SEE ALSO
          ftp(1C), getusershell(3), syslogd(1M)

     BUGS
          The anonymous account is inherently dangerous and should
          avoided when possible.

          The server must run as the super-user to create sockets with
          privileged port numbers.  It maintains an effective user id
          of the logged in user, reverting to the super-user only when
          binding addresses to sockets.  The possible security holes
          have been extensively scrutinized, but are possibly
          incomplete.

     ORIGIN
          4.3 BSD

























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