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File Transfer over Sockets
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ftpd(8c) ftpd(8c) Name ftpd - DARPA Internet File Transfer Protocol server Syntax /usr/etc/ftpd [ -d ] [ -l ] [ -ttimeout ] Description The server is the DARPA Internet File Transfer Protocol server process. The server uses the TCP protocol and is invoked by when it receives a connection on the port specified in the service specification. For further information, see The server currently supports the following requests. Case is not distinguished. Request Description ABOR Abort previous command ACCT Specify account ALLO Allocate storage 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 of 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 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 requests specified in Internet RFC 959 are recognized, but not implemented. The server interprets file names according to the globbing conventions used by This allows users to utilize the metacharacters *?[]{}~. The server authenticates users according to three rules: 1. The user name must be in the password database, 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 3. If the user name is anonymous or an anonymous 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, takes special measures to restrict the client's access privileges. The server performs a command to the home directory of the user. To prevent system security from being breached, it is recommended that the subtree be constructed with care. Thus the follow- ing rules are recommended: ~ftp) Make the home directory owned by and unwritable by anyone. ~ftp/bin) Make this directory owned by the superuser and unwritable by anyone. The program must be present to support the list commands. This program should have mode 111. ~ftp/etc) Make this directory owned by the superuser and unwritable by anyone. The files and must be present for the command to work prop- erly. These files should be mode 444. ~ftp/pub) Make this directory mode 777 and owned by Place the files, which are to be accessible by the anonymous account, in this direc- tory. Options -d Enables certain debugging messages that are printed by ftpd. -l Logs each ftp session to the -t Sends the inactivity timeout period to timeout; otherwise, the server will timeout an inactive session after 15 minutes. Restrictions Support does not exist for aborting commands. The use of an anonymous account is inherently dangerous and should be avoided when possible. The server must run as the superuser to create sockets with privileged port numbers. The server maintains an effective user id of the logged in user, reverting to the superuser only when binding addresses to sockets. The possible security holes have been extensively scru- tinized, but are possibly incomplete. Files Contains the list of unauthorized users See Also ftp(1c), services(5), inetd(8c), syslog(8) ftpd(8c)
