1Net::FTPServer(3) User Contributed Perl Documentation Net::FTPServer(3)
2
6 Net::FTPServer - A secure, extensible and configurable Perl FTP server
7
9 ftpd [--help] [-d] [-v] [-p port] [-s] [-S] [-V] [-C conf_file]
10 [-P pidfile] [-o option=value]
11
13 "Net::FTPServer" is a secure, extensible and configurable FTP server
14 written in Perl.
15 Current features include:
17 * Authenticated FTP access.
19 * Anonymous FTP access.
20 * Complete implementation of current RFCs.
21 * ASCII or binary type file transfers.
22 * Active or passive mode file transfers.
23 * Run standalone or from inetd(8).
24 * Security features: chroot, resource limits, tainting,
25 protection against buffer overflows.
26 * IP-based and/or IP-less virtual hosts.
27 * Complete access control system.
28 * Anonymous read-only FTP personality.
29 * Virtual filesystem allows files to be served
30 from a database.
31 * Directory aliases and CDPATH support.
32 * Extensible command set.
33 * Generate archives on the fly.
34
36 A standard "ftpd.conf" file is supplied with the distribution. Full
37 documentation for all the possible options which you may use in this
38 file is contained in this manual page. See the section CONFIGURATION
39 below.
40 After doing "make install", the standard "ftpd.conf" file should have
42 been installed in "/etc/ftpd.conf". You will probably need to edit this
43 file to suit your local configuration.
44 Also after doing "make install", several start-up scripts will have
46 been installed in "/usr/sbin/*ftpd.pl". (On Debian in "/usr/bin" or
47 "/usr/local/bin"). Each start-up script starts the server in a
48 different configuration: either as a full FTP server, or as an
49 anonymous-only read-only FTP server, etc.
50 The commonly used scripts are:
52 * /usr/sbin/ftpd.pl
54 * /usr/sbin/ro-ftpd.pl
55 The first script is for the full FTP server.
57 These scripts assume that the "perl" interpreter can be found on the
59 current $PATH. In the rare situation when this is not the case, you may
60 need to edit these scripts.
61 STANDALONE SERVER
63 If you have a high load site, you will want to run "Net::FTPServer" as
64 a standalone server. To start "Net::FTPServer" as a standalone server,
65 do:
66 /usr/sbin/ftpd.pl -S
68 You may want to add this to your local start-up files so that the
70 server starts automatically when you boot the machine.
71 To stop the server, do:
73 killall ftpd.pl
75 (Note: "Azazel" points out that the above is a Linux-ism. Solaris
77 administrators may get a nasty shock if they type "killall" as "root"!
78 Just kill the parent "ftpd.pl" process by hand instead).
79 RUNNING FROM INETD
81 Add the following line to "/etc/inetd.conf":
82 ftp stream tcp nowait root /usr/sbin/tcpd ftpd.pl
84 (This assumes that you have the "tcp-wrappers" package installed to
86 provide basic access control through "/etc/hosts.allow" and
87 "/etc/hosts.deny". This access control is in addition to any access
88 control which you may configure through "/etc/ftpd.conf".)
89 After editing this file you will need to inform "inetd":
91 killall -HUP inetd
93 RUNNING FROM XINETD
95 "xinetd" is a modern alternative to "inetd" which is supposedly simpler
96 to configure. In practice, however, it has proven to be quite difficult
97 to configure services under "xinetd" (mainly because "xinetd" gives no
98 diagnostic information when things go wrong). The following
99 configuration has worked for me:
100 Create the file "/etc/xinetd.d/net-ftpserver" containing:
102 # default: on
104 # description: Net::FTPServer, a secure, \
105 # extensible, configurable FTP server.
106 #
107 service ftp
108 {
109 socket_type = stream
110 wait = no
111 user = root
112 server = /usr/sbin/ftpd.pl
113 log_on_success += DURATION USERID
114 log_on_failure += USERID
115 disable = no
116 }
117 Check any other possible FTP server configurations to ensure they are
119 all disabled (ie. "disable = yes" in all other files).
120 Restart "xinetd" using:
122 /etc/init.d/xinetd restart
124
126 --help Display help and exit
127 -d, -v Enable debugging
128 -p PORT Listen on port PORT instead of the default port
129 -s Run in daemon mode (default: run from inetd)
130 -S Run in background and in daemon mode
131 -V Show version information and exit
132 -C CONF Use CONF as configuration file (default:
133 /etc/ftpd.conf)
134 -P PIDFILE Save pid into PIDFILE (daemon mode only)
135 -o option=value Override config file option with value
136 --test Test mode (used only in automatic testing scripts)
137
139 "Net::FTPServer" can be configured and extended in a number of
140 different ways.
141 Firstly, almost all common server configuration can be carried out by
143 editing the configuration file "/etc/ftpd.conf".
144 Secondly, commands can be loaded into the server at run-time to provide
146 custom extensions to the common FTP command set. These custom commands
147 are written in Perl.
148 Thirdly, one of several different supplied personalities can be chosen.
150 Personalities can be used to make deep changes to the FTP server: for
151 example, there is a supplied personality which allows the FTP server to
152 serve files from a relational database. By subclassing
153 "Net::FTPServer", "Net::FTPServer::DirHandle" and
154 "Net::FTPServer::FileHandle" you may also write your own personalities.
155 The next sections talk about each of these possibilities in turn.
157 CONFIGURATION
159 A standard "/etc/ftpd.conf" file is supplied with "Net::FTPServer" in
160 the distribution. The possible configuration options are listed in full
161 below.
162 Simple configuration options can also be given on the command line
164 using the "-o" option. Command line configuration options override
165 those from the configuration file.
166 <Include filename>
168 Use the <Include filename> directive to include the contents of
169 "filename" directly at the current point within the configuration
170 file.
171 You cannot use <Include> within a <Host> section, or at least you
173 can but it won't work the way you expect.
174 <IncludeWildcard wildcard>
176 Include all files matching "wildcard" at this point in the file.
177 The files are included in alphabetical order.
178 You cannot use <IncludeWildcard> within a <Host> section, or at
180 least you can but it won't work the way you expect.
181 debug
183 Run with debugging. Equivalent to the command line "-d" option.
184 Default: 0
186 Example: "debug: 1"
188 port
190 The TCP port number on which the FTP server listens when running in
191 daemon mode (see "daemon mode" option below).
192 Default: The standard ftp/tcp service port from "/etc/services"
194 Example: "port: 8021"
196 daemon mode
198 Run as a daemon. If set, the FTP server will open a listening
199 socket on its default port number, accept new connections and fork
200 off a new process to handle each connection. If not set (the
201 default), the FTP server will handle a single connection on
202 stdin/stdout, which is suitable for use from inetd.
203 The equivalent command line options are "-s" and "-S".
205 Default: 0
207 Example: "daemon mode: 1"
209 run in background
211 Run in the background. If set, the FTP server will fork into the
212 background before running.
213 The equivalent command line option is "-S".
215 Default: 0
217 Example: "run in background: 1"
219 error log
221 If set, then all warning and error messages are appended to this
222 file. If not set, warning and error messages get sent to STDERR and
223 to syslog.
224 Having an error log is highly recommended.
226 Default: (not set, warnings and errors go to syslog)
228 Example: "error log: /var/log/ftpd.errors"
230 rotate log files
232 If set, and if the log file names contain a '%' directive, then the
233 server will check if a new log file is needed whenever the system
234 accepts a new connection. This implements a log rotation feature
235 for long-running servers.
236 If not set, then any '%' directive will be evaluated only when the
238 log files gets created.
239 Default: (not set, log file name evaluated only once)
241 Example: "rotate log files: 1"
243 maintainer email
245 Maintainer's email address.
246 Default: root@hostname
248 Example: "maintainer email: bob@example.com"
250 class
252 Assign users into classes. One or more "class" directives can be
253 added to the configuration file to aggregate individual users into
254 larger groups of users called classes.
255 By default all anonymous users are in class "anonymous" and every
257 other user is in class "users".
258 The configuration file can contain zero or more "class" directives.
260 The format of the class directive is either:
261 class: CLASSNAME USERNAME[,USERNAME[,...]]
263 or:
265 class: CLASSNAME { perl code ... }
267 Examples of the first form are:
269 class: staff rich
271 class: students ann,mary,pete
272 User "rich" will be placed into class "staff", and users "ann",
274 "mary" and "pete" will be placed into class "students".
275 Examples of the second form are:
277 class: family { /jones$/ }
279 class: friends { $_ ne "jeff" }
280 Any username ending in "jones" (eg. "rjones", "timjones") will be
282 in class "family". Any other user except "jeff" will be placed in
283 class "friends". Note that the Perl code must be surrounded by
284 "{...}" and must return a boolean true or false value. The username
285 is available as $_. The Perl code is arbitrary: it might, for
286 example, use an external file or database lookup in order to work
287 out if a user belongs to a class.
288 "class" directives are evaluated in the order in which they appear
290 in the configuration file until one matches the username.
291 Default: Anonymous users are assigned to class "anonymous" and
293 everyone else is assigned to class "users".
294 timeout
296 Timeout on control connection. If a command has not been received
297 after this many seconds, the server drops the connection. You may
298 set this to zero to disable timeouts completely (although this is
299 not recommended).
300 Default: 900 (seconds)
302 Example: "timeout: 600"
304 limit memory
306 limit nr processes
307 limit nr files
308 Resource limits. These limits are applied to each child process and
309 are important in avoiding denial of service (DoS) attacks against
310 the FTP server.
311 Resource Default Unit
313 limit memory 16384 KBytes Amount of memory per child
314 limit nr processes 10 (none) Number of processes
315 limit nr files 20 (none) Number of open files
316 To instruct the server not to limit a particular resource, set the
318 limit to "-1".
319 Example:
321 limit memory: 32768
323 limit nr processes: 20
324 limit nr files: 40
325 limit nr processes: -1
327 max clients
329 Limit on the number of clients who can simultaneously connect. If
330 this limit is ever reached, new clients will immediately be closed.
331 It will not even ask the client to login. This feature works in
332 daemon mode only.
333 Default: 255
335 Example: "max clients: 600"
337 max clients message
339 Message to display when ``max clients'' has been reached.
340 You may use the following % escape sequences within the message for
342 internal variables:
343 %x ``max clients'' setting that has been reached
345 %E maintainer email address (from ``maintainer email''
346 setting above)
347 %G time in GMT
348 %R remote hostname or IP address if ``resolve addresses''
349 is not set
350 %L local hostname
351 %T local time
352 %% just an ordinary ``%''
353 Default: Maximum connections reached
355 Example: "max clients message: Only %x simultaneous connections
357 allowed. Please try again later."
358 resolve addresses
360 Resolve addresses. If set, attempt to do a reverse lookup on client
361 addresses for logging purposes. If you set this then some clients
362 may experience long delays when they try to connect. Not
363 recommended on high load servers.
364 Default: 0
366 Example: "resolve addresses: 1"
368 require resolved addresses
370 Require resolved addresses. If set, client addresses must validly
371 resolve otherwise clients will not be able to connect. If you set
372 this then some clients will not be able to connect, even though it
373 is probably the fault of their ISP.
374 Default: 0
376 Example: "require resolved addresses: 1"
378 change process name
380 Change process name. If set (the default) then the FTP server will
381 change its process name to reflect the IP address or hostname of
382 the client. If not set then the FTP server will not try to change
383 its process name.
384 Default: 1
386 Example: "change process name: 0"
388 greeting type
390 Greeting type. The greeting is printed before the user has logged
391 in. Possible greeting types are:
392 full Full greeting, including hostname and version number.
394 brief Hostname only.
395 terse Nothing
396 text Display greeting from ``greeting text'' option.
397 The SITE VERSION command can also reveal the version number. You
399 may need to turn this off by setting "allow site version command:
400 0" below.
401 Default: full
403 Example: "greeting type: text"
405 greeting text
407 Greeting text. If the "greeting type" is set to "text" then this
408 contains the text to display.
409 Default: none
411 Example: "greeting text: Hello. I'll be your server today."
413 welcome type
415 Welcome type. The welcome is printed after a user has logged in.
416 Possible welcome types are:
417 normal Normal welcome message: ``Welcome <<username>>.''
419 text Take the welcome message from ``welcome text'' option.
420 file Take the welcome message from ``welcome file'' file.
421 Default: normal
423 Example: "welcome type: text"
425 welcome text
427 If "welcome type" is set to "text", then this contains the text to
428 be printed after a user has logged in.
429 You may use the following % escape sequences within the welcome
431 text to substitute for internal variables:
432 %E maintainer's email address (from ``maintainer email''
434 setting above)
435 %G time in GMT
436 %R remote hostname or IP address if ``resolve addresses''
437 is not set
438 %L local hostname
439 %m user's home directory (see ``home directory'' below)
440 %T local time
441 %U username given when logging in
442 %u currently a synonym for %U, but in future will be
443 determined from RFC931 authentication, like wu-ftpd
444 %% just an ordinary ``%''
445 Default: none
447 Example: "welcome text: Welcome to this FTP server."
449 welcome file
451 If "welcome type" is set to "file", then this contains the file to
452 be printed after a user has logged in.
453 You may use any of the % escape sequences defined in "welcome text"
455 above.
456 Default: none
458 Example: "welcome file: /etc/motd"
460 home directory
462 Home directory. This is the home directory where we put the user
463 once they have logged in. This only applies to non-anonymous
464 logins. Anonymous logins are always placed in "/", which is at the
465 root of their chrooted environment.
466 You may use an absolute path here, or else one of the following
468 special forms:
469 %m Use home directory from password file or from NSS.
471 %U Username.
472 %% A single % character.
473 For example, to force a user to start in "~/anon-ftp" when they log
475 in, set this to "%m/anon-ftp".
476 Note that setting the home directory does not perform a chroot.
478 Use the "root directory" setting below to jail users into a
479 particular directory.
480 Home directories are relative to the current root directory.
482 In the anonymous read-only (ro-ftpd) personality, set home
484 directory to "/" or else you will get a warning whenever a user
485 logs in.
486 Default: %m
488 Examples:
490 home directory: %m/anon-ftp
492 home directory: /
493 root directory
495 Root directory. Immediately after logging in, perform a chroot into
496 the named directory. This only applies to non-anonymous logins, and
497 furthermore it only applies if you have a non-database VFS
498 installed. Database VFSes typically cannot perform chroot (or, to
499 be more accurate, they have a different concept of chroot -
500 typically assigning each user their own completely separate
501 namespace).
502 You may use %m and %U as above.
504 For example, to jail a user under "~/anon-ftp" after login, do:
506 home directory: /
508 root directory: %m/anon-ftp
509 Notice that the home directory is relative to the current root
511 directory.
512 Default: (none)
514 Example: "root directory: %m/anon-ftp"
516 time zone
518 Time zone to be used for MDTM and LIST stat information.
519 Default: GMT
521 Examples:
523 time zone: Etc/GMT+3
525 time zone: Europe/London
526 time zone: US/Mountain
527 local address
529 Local addresses. If you wish the FTP server (in daemon mode) to
530 only bind to a particular local interface, then give its address
531 here.
532 Default: none
534 Example: "local address: 127.0.0.1"
536 allow anonymous
538 Allow anonymous access. If set, then allow anonymous access through
539 the "ftp" and "anonymous" accounts.
540 Default: 0
542 Example: "allow anonymous: 1"
544 anonymous password check
546 anonymous password enforce
547 Validate email addresses. Normally when logging in anonymously, you
548 are asked to enter your email address as a password. These options
549 can be used to check and enforce email addresses in this field (to
550 some extent, at least -- you obviously can't force someone to enter
551 a true email address).
552 The "anonymous password check" option may be set to "rfc822", "no
554 browser", "trivial" or "none". If set to "rfc822" then the user
555 must enter a valid RFC 822 email address as password. If set to "no
556 browser" then a valid RFC 822 email address must be entered, and
557 various common browser email addresses like "mozilla@" and
558 "IEverUser@" are refused. If set to "trivial" then we just check
559 that the address contains an @ char. If set to "none", then we do
560 no checking. The default is "none".
561 If the "anonymous password enforce" option is set and the password
563 fails the check above, then the user will not be allowed to log in.
564 The default is 0 (unset).
565 These options only have effect when "allow anonymous" is set.
567 Example:
569 anonymous password check: rfc822
571 anonymous password enforce: 1
572 allow proxy ftp
574 Allow proxy FTP. If this is set, then the FTP server can be told to
575 actively connect to addresses and ports on any machine in the
576 world. This is not such a great idea, but required if you follow
577 the RFC very closely. If not set (the default), the FTP server will
578 only connect back to the client machine.
579 Default: 0
581 Example: "allow proxy ftp: 1"
583 allow connect low port
585 Allow the FTP server to connect back to ports < 1024. This is
586 rarely useful and could pose a serious security hole in some
587 circumstances.
588 Default: 0
590 Example: "allow connect low port: 1"
592 passive port range
594 What range of local ports will the FTP server listen on in passive
595 mode? Choose a range here like "1024-5999,49152-65535". The special
596 value 0 means that the FTP server will use a kernel-assigned
597 ephemeral port.
598 Default: 49152-65535
600 Example: "passive port range: 0"
602 ftp data port
604 Which source port to use for active (non-passive) mode when
605 connecting to the client for PORT mode transfers. The special
606 value 0 means that the FTP server will use a kernel-assigned
607 ephemeral port. To strictly follow RFC, this should be set to
608 "ftp-data(20)". This may be required for certain brain-damaged
609 firewall configurations. However, for security reasons, the
610 default setting is intentionally set to 0 to utilize a kernel-
611 assigned ephemeral port. Use this directive at your own risk!
612 SECURITY PRECAUTIONS:
614 1) Unfortunately, to use a port < 1024 requires super-user
616 privileges. Thus, low ports will not work unless the FTP server is
617 invoked as super-user. This also implies that all processes
618 handling the client connections must also remain super-user
619 throughout the entire session. It is highly discouraged to use a
620 low port.
621 http://cr.yp.to/ftp/security.html
623 (See "Connection laundering" section)
624 2) There sometimes exists a danger of needing to connect to the
626 same remote host:port. Using the same IP/port on both sides will
627 cause connect() to fail if the old socket is still being broken
628 down. This condition will not occur if using an ephemeral port.
629 http://groups.google.com/groups?selm=fa.epucqgv.1l2kl0e@ifi.uio.no
631 (See "unable to create socket" comment)
632 3) Many hackers use source port 20 to blindly circumvent certain
634 naive firewalls. Using an ephemeral port (the default) may help
635 discourage such dangerous naivety.
636 man nmap
638 (See the -g option)
639 Default: 0
641 Example: "ftp data port: ftp-data"
643 max login attempts
645 Maximum number of login attempts before we drop the connection and
646 issue a warning in the logs. Wu-ftpd defaults this to 5.
647 Default: 3
649 Example: "max login attempts: 5"
651 pam authentication
653 Use PAM for authentication. Required on systems such as Red Hat
654 Linux and Solaris which use PAM for authentication rather than the
655 normal "/etc/passwd" mechanisms. You will need to have the
656 "Authen::PAM" Perl module installed for this to work.
657 Default: 0
659 Example: "pam authentication: 1"
661 pam application name
663 If PAM authentication is enabled, then this is the PAM application
664 name. I have used "ftp" as the default which is the same name that
665 wu-ftpd chooses. FreeBSD users will want to use "ftpd" here.
666 Default: ftp
668 Example: "pam application name: ftpd"
670 password file
672 Only in the "Full" personality, this allows you to specify a
673 password file which is used for authentication. If you enable this
674 option, then normal PAM or "/etc/passwd" is bypassed and this
675 password file is used instead.
676 Each line in the password file has the following format:
678 username:crypted_password:unix_user[:root_directory]
680 Comments and blank lines are ignored.
682 For example, a line with:
684 guest:ab01FAX.bQRSU:rich:/home/rich/guest-uploads
686 would allow someone to log in as "guest" with password 123456.
688 After logging in, the FTP server will assume the identity of the
689 real Unix user "rich", and will chroot itself into the
690 "/home/rich/guest-uploads" directory.
691 (Note that because ordinary PAM/"passwd" is bypassed, it would no
693 longer be possible for a user to log in directly with the username
694 "rich").
695 Crypted passwords can be generated using the following command:
697 perl -e 'print crypt ("123456", "ab"), "\n"'
699 Replace 123456 with the actual password, and replace "ab" with two
701 random letters from the set "[a-zA-Z0-9./]". (The two random
702 letters are the so-called salt and are used to make dictionary
703 attacks against the password file more difficult - see crypt(3)).
704 The user's home directory comes from the real Unix password file
706 (or nsswitch-configured source) for the real Unix user. You cannot
707 use password files to override this, and so if you are using the
708 optional "root_directory" parameter, it would make sense to add
709 "home directory: /" into your configuration file.
710 Anonymous logins are not affected by the "password file" option.
712 Use the "allow anonymous" flag to control whether anonymous logins
713 are permitted in the "Full" back-end.
714 Password files are not the height of security, but they are
716 included because they can sometimes be useful. In particular if the
717 password file can be read by untrusted users then it is likely that
718 those same users can run the crack program and eventually find out
719 your passwords. Some small additional security is offered by having
720 the password file readable only by root (mode 0600). In future we
721 may offer MD5 or salted SHA-1 hashed passwords to make this harder.
722 A curious artifact of the implementation allows you to list the
724 same user with multiple different passwords. Any of the passwords
725 is then valid for logins (and you could even have the user map to
726 different real Unix users in different chrooted directories!)
727 Default: (none)
729 Example: "password file: /etc/ftpd.passwd"
731 pidfile
733 Location of the file to store the process ID (PID). Applies only
734 to the deamonized process, not the child processes.
735 Default: (no pidfile created)
737 Example: "pidfile: /var/run/ftpd.pid"
739 client logging
741 Location to store all client commands sent to the server. The
742 format is the date, the pid, and the command. Following the pid is
743 a "-" if not authenticated the username if the connection is
744 authenticated. Example of before and after authentication:
745 [Wed Feb 21 18:41:32 2001][23818:-]USER rob
747 [Wed Feb 21 18:41:33 2001][23818:-]PASS 123456
748 [Wed Feb 21 18:41:33 2001][23818:*]SYST
749 Default: (no logging)
751 Examples:
753 client logging: /var/log/ftpd.log
755 client logging: /tmp/ftpd_log.$hostname
756 xfer logging
758 Location of transfer log. The format was taken from wu-ftpd and
759 ProFTPD xferlog. (See also "man xferlog")
760 Default: (no logging)
762 Examples:
764 xfer logging: /var/log/xferlog
766 xfer logging: /tmp/xferlog.$hostname
767 hide passwords in client log
769 If set to 1, then password ("PASS") commands will not be logged in
770 the client log. This option has no effect unless client logging is
771 enabled.
772 Default: 0 (PASS lines will be shown)
774 Example: "hide passwords in client log: 1"
776 enable syslog
778 Enable syslogging. If set, then Net::FTPServer will send much
779 information to syslog. On many systems, this information will be
780 available in /var/log/messages or /var/adm/messages. If clear,
781 syslogging is disabled.
782 Default: 1
784 Example: "enable syslog: 0"
786 ident timeout
788 Timeout for ident authentication lookups. A timeout (in seconds)
789 must be specified in order to enable ident lookups. There is no
790 way to specify an infinite timeout. Use 0 to disable this feature.
791 Default: 0
793 Example: "ident timeout: 10"
795 access control rule
797 user access control rule
798 retrieve rule
799 store rule
800 delete rule
801 list rule
802 mkdir rule
803 rename rule
804 chdir rule
805 Access control rules.
806 Access control rules are all specified as short snippets of Perl
808 script. This allows the maximum configurability -- you can express
809 just about any rules you want -- but at the price of learning a
810 little Perl.
811 You can use the following variables from the Perl:
813 $hostname Resolved hostname of the client [1]
815 $ip IP address of the client
816 $user User name [2]
817 $class Class of user [2]
818 $user_is_anonymous True if the user is an anonymous user [2]
819 $pathname Full pathname of the file being affected [2]
820 $filename Filename of the file being affected [2,3]
821 $dirname Directory name containing file being affected [2]
822 $type 'A' for ASCII, 'B' for binary, 'L8' for local 8-bit
823 $form Always 'N'
824 $mode Always 'S'
825 $stru Always 'F'
826 Notes:
828 [1] May be undefined, particularly if "resolve addresses" is not
830 set.
831 [2] Not available in "access control rule" since the user has not
833 logged in at this point.
834 [3] Not available for "list directory rule".
836 Access control rule. The FTP server will not accept any connections
838 from a site unless this rule succeeds. Note that only $hostname and
839 $ip are available to this rule, and unless "resolve addresses" and
840 "require resolved addresses" are both set $hostname may be
841 undefined.
842 Default: 1
844 Examples:
846 (a) Deny connections from *.badguys.com:
848 access control rule: defined ($hostname) && \
850 $hostname !~ /\.badguys\.com$/
851 (b) Only allow connections from local network 10.0.0.0/24:
853 access control rule: $ip =~ /^10\./
855 User access control rule. After the user logs in successfully, this
857 rule is then called to determine if the user may be permitted
858 access.
859 Default: 1
861 Examples:
863 (a) Only allow ``rich'' to log in from 10.x.x.x network:
865 user access control rule: $user ne "rich" || \
867 $ip =~ /^10\./
868 (b) Only allow anonymous users to log in if they come from
870 hosts with resolving hostnames (``resolve addresses'' must
871 also be set):
872 user access control rule: !$user_is_anonymous || \
874 defined ($hostname)
875 (c) Do not allow user ``jeff'' to log in at all:
877 user access control rule: $user ne "jeff"
879 Retrieve rule. This rule controls who may retrieve (download)
881 files.
882 Default: 1
884 Examples:
886 (a) Do not allow anyone to retrieve ``/etc/*'' or any file anywhere
888 called ``.htaccess'':
889 retrieve rule: $dirname !~ m(^/etc/) && $filename ne ".htaccess"
891 (b) Only allow anonymous users to retrieve files from under the
893 ``/pub'' directory.
894 retrieve rule: !$user_is_anonymous || $dirname =~ m(^/pub/)
896 Store rule. This rule controls who may store (upload) files.
898 In the anonymous read-only (ro-ftpd) personality, it is not
900 possible to upload files anyway, so setting this rule has no
901 effect.
902 Default: 1
904 Examples:
906 (a) Only allow users to upload files to the ``/incoming''
908 directory.
909 store rule: $dirname =~ m(^/incoming/)
911 (b) Anonymous users can only upload files to ``/incoming''
913 directory.
914 store rule: !$user_is_anonymous || $dirname =~ m(^/incoming/)
916 (c) Disable file upload.
918 store rule: 0
920 Delete rule. This rule controls who may delete files or rmdir
922 directories.
923 In the anonymous read-only (ro-ftpd) personality, it is not
925 possible to delete files anyway, so setting this rule has no
926 effect.
927 Default: 1
929 Example: "delete rule: 0"
931 List rule. This rule controls who may list out the contents of a
933 directory.
934 Default: 1
936 Example: "list rule: $dirname =~ m(^/pub/)"
938 Mkdir rule. This rule controls who may create a subdirectory.
940 In the anonymous read-only (ro-ftpd) personality, it is not
942 possible to create directories anyway, so setting this rule has no
943 effect.
944 Default: 1
946 Example: "mkdir rule: 0"
948 Rename rule. This rule controls which files or directories can be
950 renamed.
951 Default: 1
953 Example: "rename rule: $pathname !~ m(/.htaccess$)"
955 Chdir rule. This rule controls which directories are acceptable to
957 a CWD or CDUP.
958 Example: "chdir rule: $pathname !~ m/private/"
960 chdir message file
962 Change directory message file. If set, then the first time (per
963 session) that a user goes into a directory which contains a file
964 matching this name, that file will be displayed.
965 The file may contain any of the following % escape sequences:
967 %C current working directory
969 %E maintainer's email address (from ``maintainer email''
970 setting above)
971 %G time in GMT
972 %R remote hostname or IP address if ``resolve addresses''
973 is not set
974 %L local hostname
975 %m user's home directory (see ``home directory'' below)
976 %T local time
977 %U username given when logging in
978 %u currently a synonym for %U, but in future will be
979 determined from RFC931 authentication, like wu-ftpd
980 %% just an ordinary ``%''
981 Default: (none)
983 Example: "chdir message file: .message"
985 allow rename to overwrite
987 Allow the rename (RNFR/RNTO) command to overwrite files. If unset,
988 then we try to test whether the rename command would overwrite a
989 file and disallow it. However there are some race conditions with
990 this test.
991 Default: 1
993 Example: "allow rename to overwrite: 0"
995 allow store to overwrite
997 Allow the store commands (STOR/STOU/APPE) to overwrite files. If
998 unset, then we try to test whether the store command would
999 overwrite a file and disallow it. However there are some race
1000 conditions with this test.
1001 Default: 1
1003 Example: "allow store to overwrite: 0"
1005 alias
1007 Define an alias "name" for directory "dir". For example, the
1008 command "alias: mirror /pub/mirror" would allow the user to access
1009 the "/pub/mirror" directory directly just by typing "cd mirror".
1010 Aliases only apply to the cd (CWD) command. The "cd foo" command
1012 checks for directories in the following order:
1013 foo in the current directory
1015 an alias called foo
1016 foo in each directory in the cdpath (see ``cdpath'' command below)
1017 You may list an many aliases as you want.
1019 Alias names cannot contain slashes (/).
1021 Although alias dirs may start without a slash (/), this is unwise
1023 and it's better that they always start with a slash (/) char.
1024 General format: "alias: name dir"
1026 cdpath
1028 Define a search path which is used when changing directories. For
1029 example, the command "cdpath: /pub/mirror /pub/sites" would allow
1030 the user to access the "/pub/mirror/ftp.cpan.org" directory
1031 directly by just typing "cd ftp.cpan.org".
1032 The "cd foo" command checks for directories in the following order:
1034 foo in the current directory
1036 an alias called foo (see ``alias'' command above)
1037 foo in each directory in the cdpath
1038 General format: "cdpath: dir1 [dir2 [dir3 ...]]"
1040 allow site version command
1042 SITE VERSION command. If set, then the SITE VERSION command reveals
1043 the current Net::FTPServer version string. If unset, then the
1044 command is disabled.
1045 Default: 1
1047 Example: "allow site version command: 0"
1049 allow site exec command
1051 SITE EXEC command. If set, then the SITE EXEC command allows
1052 arbitrary commands to be executed on the server as the current
1053 user. If unset, then this command is disabled. The default is
1054 disabled for obvious security reasons.
1055 If you do allow SITE EXEC, you may need to increase the per process
1057 memory, processes and files limits above.
1058 Default: 0
1060 Example: "allow site exec command: 1"
1062 enable archive mode
1064 Archive mode. If set (the default), then archive mode is enabled,
1065 allowing users to request, say, "file.gz" and get a version of
1066 "file" which is gzip-compressed on the fly. If zero, then this
1067 feature is disabled. See the section ARCHIVE MODE elsewhere in this
1068 manual for details.
1069 Since archive mode is implemented using external commands, you need
1071 to ensure that programs such as "gzip", "compress", "bzip2",
1072 "uuencode", etc. are available on the $PATH (even in the chrooted
1073 environment), and you also need to substantially increase the
1074 normal per-process memory, processes and files limits.
1075 Default: 1
1077 Example: "enable archive mode: 0"
1079 archive zip temporaries
1081 Temporary directory for generating ZIP files in archive mode. In
1082 archive mode, when generating ZIP files, the FTP server is capable
1083 of either creating a temporary file on local disk containing the
1084 ZIP contents, or can generate the file completely in memory. The
1085 former method saves memory. The latter method (only practical on
1086 small ZIP files) allows the server to work more securely and in
1087 certain read-only chrooted environments.
1088 (Unfortunately the ZIP file format itself prevents ZIP files from
1090 being easily created on the fly).
1091 If not specified in the configuration file, this option defaults to
1093 using "/tmp". If there are local users on the FTP server box, then
1094 this can lead to various "tmp" races, so for maximum security you
1095 will probably want to change this.
1096 If specified, and set to a string, then the string is the name of a
1098 directory which is used for storing temporary zip files. This
1099 directory must be writable, and must exist inside the chrooted
1100 environment (if chroot is being used).
1101 If specified, but set to "0" or an empty string, then the server
1103 will always generate the ZIP file in memory.
1104 In any case, if the directory is found at runtime to be unwritable,
1106 then the server falls back to creating ZIP files in memory.
1107 Default: "/tmp"
1109 Example: "archive zip temporaries: "
1111 Example: "archive zip temporaries: /var/ziptmp"
1113 site command
1115 Custom SITE commands. Use this command to define custom SITE
1116 commands. Please read the section LOADING CUSTOMIZED SITE COMMANDS
1117 in this manual page for more detailed information.
1118 The "site command" command has the form:
1120 "site command: cmdname file"
1122 cmdname is the name of the command (eg. for SITE README you would
1124 set cmdname == "readme"). file is a file containing the code of the
1125 site command in the form of an anonymous Perl subroutine. The file
1126 should have the form:
1127 sub {
1129 my $self = shift; # The FTPServer object.
1130 my $cmd = shift; # Contains the command itself.
1131 my $rest = shift; # Contains any parameters passed by the user.
1132 : :
1134 : :
1135 $self->reply (RESPONSE_CODE, RESPONSE_TEXT);
1137 }
1138 You may define as many site commands as you want. You may also
1140 override site commands from the current personality here.
1141 Example:
1143 site command: quota /usr/local/lib/ftp/quota.pl
1145 and the file "/usr/local/lib/ftp/quota.pl" contains:
1147 sub {
1149 my $self = shift; # The FTPServer object.
1150 my $cmd = shift; # Contains "QUOTA".
1151 my $rest = shift; # Contains parameters passed by user.
1152 # ... Some code to compute the user's quota ...
1154 $self->reply (200, "Your quota is $quota MB.");
1156 }
1157 The client types "SITE QUOTA" and the server responds with:
1159 "200 Your quota is 12.5 MB.".
1161 <Host hostname> ... </Host>
1163 <Host hostname> ... </Host> encloses commands which are applicable
1164 only to a particular host. "hostname" may be either a fully-
1165 qualified domain name (for IP-less virtual hosts) or an IP address
1166 (for IP-based virtual hosts). You should read the section VIRTUAL
1167 HOSTS in this manual page for more information on the different
1168 types of virtual hosts and how to set it up in more detail.
1169 Note also that unless you have set "enable virtual hosts: 1", all
1171 <Host> sections will be ignored.
1172 enable virtual hosts
1174 Unless this option is uncommented, virtual hosting is disabled and
1175 the <Host> sections in the configuration file have no effect.
1176 Default: 0
1178 Example: "enable virtual hosts: 1"
1180 virtual host multiplex
1182 IP-less virtual hosts. If you want to enable IP-less virtual hosts,
1183 then you must set up your DNS so that all hosts map to a single IP
1184 address, and place that IP address here. This is roughly equivalent
1185 to the Apache "NameVirtualHost" option.
1186 IP-less virtual hosting is an experimental feature which requires
1188 changes to clients.
1189 Default: (none)
1191 Example: "virtual host multiplex: 1.2.3.4"
1193 Example <Host> section. Allow the dangerous SITE EXEC command on
1195 local connections. (Note that this is still dangerous).
1196 <Host localhost.localdomain>
1198 ip: 127.0.0.1
1199 allow site exec command: 1
1200 </Host>
1201 Example <Host> section. This shows you how to do IP-based virtual
1203 hosts. I assume that you have set up your DNS so that
1204 "ftp.bob.example.com" maps to IP 1.2.3.4 and "ftp.jane.example.com"
1205 maps to IP 1.2.3.5, and you have set up suitable IP aliasing in the
1206 kernel.
1207 You do not need the "ip:" command if you have configured reverse
1209 DNS correctly AND you trust your local DNS servers.
1210 <Host ftp.bob.example.com>
1212 ip: 1.2.3.4
1213 root directory: /home/bob
1214 home directory: /
1215 user access control rule: $user eq "bob"
1216 maintainer email: bob@bob.example.com
1217 </Host>
1218 <Host ftp.jane.example.com>
1220 ip: 1.2.3.5
1221 root directory: /home/jane
1222 home directory: /
1223 allow anonymous: 1
1224 user access control rule: $user_is_anonymous
1225 maintainer email: jane@jane.example.com
1226 </Host>
1227 These rules set up two virtual hosts called "ftp.bob.example.com"
1229 and "ftp.jane.example.com". The former is located under bob's home
1230 directory and only he is allowed to log in. The latter is located
1231 under jane's home directory and only allows anonymous access.
1232 Example <Host> section. This shows you how to do IP-less virtual
1234 hosts. Note that IP-less virtual hosts are a highly experimental
1235 feature, and require the client to support the HOST command.
1236 You need to set up your DNS so that both "ftp.bob.example.com" and
1238 "ftp.jane.example.com" point to your own IP address.
1239 virtual host multiplex: 1.2.3.4
1241 <Host ftp.bob.example.com>
1243 root directory: /home/bob
1244 home directory: /
1245 user access control rule: $user eq "bob"
1246 </Host>
1247 <Host ftp.jane.example.com>
1249 root directory: /home/jane
1250 home directory: /
1251 allow anonymous: 1
1252 user access control rule: $user_is_anonymous
1253 </Host>
1254 log socket type
1256 Socket type for contacting syslog. This is the argument to the
1257 "Sys::Syslog::setlogsock" function.
1258 Default: unix
1260 Example: "log socket type: inet"
1262 listen queue
1264 Length of the listen queue when running in daemon mode.
1265 Default: 10
1267 Example: "listen queue: 20"
1269 tcp window
1271 Set TCP window. See RFC 2415 Simulation Studies of Increased
1272 Initial TCP Window Size. This setting only affects the data
1273 socket. It's not likely that you will need to or should change this
1274 setting from the system-specific default.
1275 Default: (system-specific TCP window size)
1277 Example: "tcp window: 4380"
1279 tcp keepalive
1281 Set TCP keepalive.
1282 Default: (system-specific keepalive setting)
1284 Example: "tcp keepalive: 1"
1286 command filter
1288 Command filter. If set, then all commands are checked against this
1289 regular expression before being executed. If a command doesn't
1290 match the filter, then the command connection is immediately
1291 dropped. This is equivalent to the "AllowFilter" command in
1292 ProFTPD. Remember to include "^...$" around the filter.
1293 Default: (no filter)
1295 Example: "command filter: ^[A-Za-z0-9 /]+$"
1297 restrict command
1299 Advanced command filtering. The "restrict command" directive takes
1300 the form:
1301 restrict command: "COMMAND" perl code ...
1303 If the user tries to execute "COMMAND", then the "perl code" is
1305 evaluated first. If it evaluates to true, then the command is
1306 allowed to proceed. Otherwise the server reports an error back to
1307 the user and does not execute the command.
1308 Note that the "COMMAND" is the FTP protocol command, which is not
1310 necessarily the same as the command which users will type in on
1311 their FTP clients. Please read RFC 959 to see some of the more
1312 common FTP protocol commands.
1313 The Perl code has the same variables available to it as for access
1315 control rules (eg. $user, $class, $ip, etc.). The code must not
1316 alter the global $_ variable (which contains the complete command).
1317 Default: all commands are allowed by default
1319 Examples:
1321 Only allow users in the class "nukers" to delete files and
1323 directories:
1324 restrict command: "DELE" $class eq "nukers"
1326 restrict command: "RMD" $class eq "nukers"
1327 Only allow staff to use the "SITE WHO" command:
1329 restrict command: "SITE WHO" $class eq "staff"
1331 Only allow "rich" to run the "SITE EXEC" command:
1333 allow site exec command: 1
1335 restrict command: "SITE EXEC" $user eq "rich"
1336 command wait
1338 Go slow. If set, then the server will sleep for this many seconds
1339 before beginning to process each command. This command would be a
1340 lot more useful if you could apply it only to particular classes of
1341 connection.
1342 Default: (no wait)
1344 Example: "command wait: 5"
1346 no authentication commands
1348 The list of commands which a client may issue before they have
1349 authenticated themselves is very limited. Obviously "USER" and
1350 "PASS" are allowed (otherwise a user would never be able to log
1351 in!), also "QUIT", "LANG", "HOST" and "FEAT". "HELP" is also
1352 permitted (although dubious). Any other commands not on this list
1353 will result in a 530 Not logged in. error.
1354 This list ought to contain at least "USER", "PASS" and "QUIT"
1356 otherwise the server won't be very functional.
1357 Some commands cannot be added here -- eg. adding "CWD" or "RETR" to
1359 this list is likely to make the FTP server crash, or else enable
1360 users to read files only available to root. Hence use this with
1361 great care.
1362 Default: USER PASS QUIT LANG HOST FEAT HELP
1364 Example: "no authentication commands: USER PASS QUIT"
1366 <Perl> ... </Perl>
1368 Use the <Perl> directive to write Perl code directly into your
1369 configuration file. Here is a simple example:
1370 <Perl>
1372 use Sys::Hostname;
1373 $config{'maintainer email'} = "root\@" . hostname ();
1374 $config{port} = 8000 + 21;
1375 $config{debug} = $ENV{FTP_DEBUG} ? 1 : 0;
1376 </Perl>
1377 As shown in the example, to set a configuration option called
1379 "foo", you simply assign to the variable $config{foo}.
1380 All normal Perl functionality is available to you, including use of
1382 "require" if you need to run an external Perl script.
1383 The <Perl> and </Perl> directives must each appear on a single line
1385 on their own.
1386 To assign multiple configuration options with the same name, use an
1388 array ref:
1389 <Perl>
1391 my @aliases = ( "foo /pub/foo",
1392 "bar /pub/bar",
1393 "baz /pub/baz" );
1394 $config{alias} = \@aliases;
1395 </Perl>
1396 You cannot use a <Perl> section within a <Host> section. Instead,
1398 you must simulate it by assigning to the %host_config variable like
1399 this:
1400 <Perl>
1402 $host_config{'localhost.localdomain'}{ip} = "127.0.0.1";
1403 $host_config{'localhost.localdomain'}{'allow site exec command'}= 1;
1404 </Perl>
1405 The above is equivalent to the following ordinary <Host> section:
1407 <Host localhost.localdomain>
1409 ip: 127.0.0.1
1410 allow site exec command: 1
1411 </Host>
1412 You may also assign to the $self variable in order to set variables
1414 directly in the "Net::FTPServer" object itself. This is pretty
1415 hairy, and hence not recommended, but you dig your own hole if you
1416 want. Here is a contrived example:
1417 <Perl>
1419 $self->{version_string} = "my FTP server/1.0";
1420 </Perl>
1421 A cleaner, but more complex way to do this would be to use a
1423 personality.
1424 The <Perl> directive is potentially quite powerful. Here is a good
1426 idea that Rob Brown had:
1427 <Perl>
1429 my %H;
1430 dbmopen (%H, "/etc/ftpd.db", 0644);
1431 %config = %H;
1432 dbmclose (%H);
1433 </Perl>
1434 Notice how this allows you to crunch a possibly very large
1436 configuration file into a hash, for very rapid loading at run time.
1437 Another useful way to use <Perl> is to set environment variables
1439 (particularly $PATH).
1440 <Perl>
1442 $ENV{PATH} = "/usr/local/bin:$ENV{PATH}"
1443 </Perl>
1444 Here's yet another wonderful way to use <Perl>. Look in
1446 "/usr/local/lib/ftp/" for a list of site commands and load each
1447 one:
1448 <Perl>
1450 my @files = glob "/usr/local/lib/ftp/*.pl";
1452 my @site_commands;
1453 foreach (@files)
1455 {
1456 push @site_commands, "$1 $_" if /([a-z]+)\.pl/;
1457 }
1458 $config{'site command'} = \@site_commands;
1460 </Perl>
1462 To force a particular version of Net::FTPServer to be used, include
1464 the following code in your configuration file:
1465 <Perl>
1467 die "requires Net::FTPServer version >= 1.025"
1468 unless $Net::FTPServer::VERSION !~ /\..*\./ &&
1469 $Net::FTPServer::VERSION >= 1.025;
1470 </Perl>
1471 LOADING CUSTOMIZED SITE COMMANDS
1473 It is very simple to write custom SITE commands. These commands are
1474 available to users when they type "SITE XYZ" in a command line FTP
1475 client or when they define a custom SITE command in their graphical FTP
1476 client.
1477 SITE commands are unregulated by RFCs. You may define any commands and
1479 give them any names and any function you wish. However, over time
1480 various standard SITE commands have been recognized and implemented in
1481 many FTP servers. "Net::FTPServer" also implements these. They are:
1482 SITE VERSION Display the server software version.
1484 SITE EXEC Execute a shell command on the server (in
1485 C<Net::FTPServer> this is disabled by default!)
1486 SITE ALIAS Display chdir aliases.
1487 SITE CDPATH Display chdir paths.
1488 SITE CHECKMETHOD Implement checksums.
1489 SITE CHECKSUM
1490 SITE IDLE Get or set the idle timeout.
1491 SITE SYNC Synchronize hard disks.
1492 The following commands are found in "wu-ftpd", but not currently
1494 implemented by "Net::FTPServer": SITE CHMOD, SITE GPASS, SITE GROUP,
1495 SITE GROUPS, SITE INDEX, SITE MINFO, SITE NEWER, SITE UMASK.
1496 So when you are choosing a name for a SITE command, it is probably best
1498 not to choose one of the above names, unless you are specifically
1499 implementing or overriding that command.
1500 Custom SITE commands have to be written in Perl. However, there is very
1502 little you need to understand in order to write these commands -- you
1503 will only need a basic knowledge of Perl scripting.
1504 As our first example, we will implement a "SITE README" command. This
1506 command just prints out some standard information.
1507 Firstly create a file called "/usr/local/lib/site_readme.pl" (you may
1509 choose a different path if you want). The file should contain:
1510 sub {
1512 my $self = shift;
1513 my $cmd = shift;
1514 my $rest = shift;
1515 $self->reply (200,
1517 "This is the README file for mysite.example.com.",
1518 "Mirrors are contained in /pub/mirrors directory.",
1519 " : : : : :",
1520 "End of the README file.");
1521 }
1522 Edit "/etc/ftpd.conf" and add the following command:
1524 site command: readme /usr/local/lib/site_readme.pl
1526 and restart the FTP server (check your system log [/var/log/messages]
1528 for any syntax errors or other problems). Here is an example of a user
1529 running the SITE README command:
1530 ftp> quote help site
1532 214-The following commands are recognized:
1533 214- ALIAS CHECKMETHOD EXEC README
1534 214- CDPATH CHECKSUM IDLE VERSION
1535 214 You can also use HELP to list general commands.
1536 ftp> site readme
1537 200-This is the README file for mysite.example.com.
1538 200-Mirrors are contained in /pub/mirrors directory.
1539 200- : : : : :
1540 200 End of the README file.
1541 Our second example demonstrates how to use parameters (the $rest
1543 argument). This is the "SITE ECHO" command.
1544 sub {
1546 my $self = shift;
1547 my $cmd = shift;
1548 my $rest = shift;
1549 # Split the parameters up.
1551 my @params = split /\s+/, $rest;
1552 # Quote each parameter.
1554 my $reply = join ", ", map { "'$_'" } @params;
1555 $self->reply (200, "You said: $reply");
1557 }
1558 Here is the "SITE ECHO" command in use:
1560 ftp> quote help site
1562 214-The following commands are recognized:
1563 214- ALIAS CHECKMETHOD ECHO IDLE
1564 214- CDPATH CHECKSUM EXEC VERSION
1565 214 You can also use HELP to list general commands.
1566 ftp> site echo hello how are you?
1567 200 You said: 'hello', 'how', 'are', 'you?'
1568 Our third example is more complex and shows how to interact with the
1570 virtual filesystem (VFS). The "SITE SHOW" command will be used to list
1571 text files directly (the user normally has to download the file and
1572 view it locally). Hence "SITE SHOW readme.txt" should print the
1573 contents of the "readme.txt" file in the local directory (if it
1574 exists).
1575 All file accesses must be done through the VFS, not by directly
1577 accessing the disk. If you follow this convention then your commands
1578 will be secure and will work correctly with different back-end
1579 personalities (in particular when ``files'' are really blobs in a
1580 relational database).
1581 sub {
1583 my $self = shift;
1584 my $cmd = shift;
1585 my $rest = shift;
1586 # Get the file handle.
1588 my ($dirh, $fileh, $filename) = $self->_get ($rest);
1589 # File doesn't exist or not accessible. Return an error.
1591 unless ($fileh)
1592 {
1593 $self->reply (550, "File or directory not found.");
1594 return;
1595 }
1596 # Check it's a simple file.
1598 my ($mode) = $fileh->status;
1599 unless ($mode eq "f")
1601 {
1602 $self->reply (550,
1603 "SITE SHOW command is only supported on plain files.");
1604 return;
1605 }
1606 # Try to open the file.
1608 my $file = $fileh->open ("r");
1609 unless ($file)
1611 {
1612 $self->reply (550, "File or directory not found.");
1613 return;
1614 }
1615 # Copy data into memory.
1617 my @lines = ();
1618 while (defined ($_ = $file->getline))
1620 {
1621 # Remove any native line endings.
1622 s/[\n\r]+$//;
1623 push @lines, $_;
1625 }
1626 # Close the file handle.
1628 unless ($file->close)
1629 {
1630 $self->reply (550, "Close failed: ".$self->system_error_hook());
1631 return;
1632 }
1633 # Send the file back to the user.
1635 $self->reply (200, "File $filename:", @lines, "End of file.");
1636 }
1637 This code is not quite complete. A better implementation would also
1639 check the "retrieve rule" (so that people couldn't use "SITE SHOW" in
1640 order to get around access control limitations which the server
1641 administrator has put in place). It would also check the file more
1642 closely to make sure it was a text file and would refuse to list very
1643 large files.
1644 Here is an example (abbreviated) of a user using the "SITE SHOW"
1646 command:
1647 ftp> site show README
1649 200-File README:
1650 200-$Id: FTPServer.pm,v 1.11 2005/07/15 10:10:22 rwmj Exp $
1651 200-
1652 200-Net::FTPServer - A secure, extensible and configurable Perl FTP server.
1653 [...]
1654 200-To contact the author, please email: Richard Jones <rich@annexia.org>
1655 200 End of file.
1656 STANDARD PERSONALITIES
1658 Currently "Net::FTPServer" is supplied with three standard
1659 personalities. These are:
1660 Full The complete read/write anonymous/authenticated FTP
1662 server which serves files from a standard Unix filesystem.
1663 RO A small read-only anonymous-only FTP server similar
1665 in functionality to Dan Bernstein's publicfile
1666 program.
1667 DBeg1 An example FTP server which serves files to a PostgreSQL
1669 database. This supports files and hierarchical
1670 directories, multiple users (but not file permissions)
1671 and file upload.
1672 The standard Full personality will not be explained here.
1674 The RO personality is the Full personality with all code related to
1676 writing files, creating directories, deleting, etc. removed. The RO
1677 personality also only permits anonymous logins and does not contain any
1678 code to do ordinary authentication. It is therefore safe to use the RO
1679 personality where you are only interested in serving files to anonymous
1680 users and do not want to worry about crackers discovering a way to
1681 trick the FTP server into writing over a file.
1682 The DBeg1 personality is a complete read/write FTP server which stores
1684 files as BLOBs (Binary Large OBjects) in a PostgreSQL relational
1685 database. The personality supports file download and upload and
1686 contains code to authenticate users against a "users" table in the
1687 database (database ``users'' are thus completely unrelated to real Unix
1688 users). The DBeg1 is intended only as an example. It does not support
1689 advanced features such as file permissions and quotas. As part of the
1690 schoolmaster.net project Bibliotech Ltd. have developed an even more
1691 advanced database personality which supports users, groups, access
1692 control lists, quotas, recursive moves and copies and many other
1693 features. However this database personality is not available as source.
1694 To use the DBeg1 personality you must first run a PostgreSQL server
1696 (version 6.4 or above) and ensure that you have access to it from your
1697 local user account. Use the "initdb", "createdb" and "createuser"
1698 commands to create the appropriate user account and database (please
1699 consult the PostgreSQL administrators manual for further information
1700 about this -- I do not answer questions about basic PostgreSQL
1701 knowledge).
1702 Here is my correctly set up PostgreSQL server, accessed from my local
1704 user account ``rich'':
1705 cruiser:~$ psql
1707 Welcome to the POSTGRESQL interactive sql monitor:
1708 Please read the file COPYRIGHT for copyright terms of POSTGRESQL
1709 type \? for help on slash commands
1711 type \q to quit
1712 type \g or terminate with semicolon to execute query
1713 You are currently connected to the database: rich
1714 rich=> \d
1716 Couldn't find any tables, sequences or indices!
1717 You will also need the following Perl modules installed: DBI, DBD::Pg.
1719 Now you will need to create a database called ``ftp'' and populate it
1721 with data. This is how to do this:
1722 createdb ftp
1724 psql ftp < doc/eg1.sql
1725 Check that no ERRORs are reported by PostgreSQL.
1727 You should now be able to start the FTP server by running the following
1729 command (not as root):
1730 ./dbeg1-ftpd -S -p 2000 -C ftpd.conf
1732 If the FTP server doesn't start correctly, you should check the system
1734 log file [/var/log/messages].
1735 Connect to the FTP server as follows:
1737 ftp localhost 2000
1739 Log in as either rich/123456 or dan/123456 and then try to move around,
1741 upload and download files, create and delete directories, etc.
1742 SUBCLASSING THE Net::FTPServer CLASSES
1744 By subclassing "Net::FTPServer", "Net::FTPServer::DirHandle" and/or
1745 "Net::FTPServer::FileHandle" you can create custom personalities for
1746 the FTP server.
1747 Typically by overriding the hooks in the "Net::FTPServer" class you can
1749 change the basic behaviour of the FTP server - turning it into an
1750 anonymous read-only server, for example.
1751 By overriding the hooks in "Net::FTPServer::DirHandle" and
1753 "Net::FTPServer::FileHandle" you can create virtual filesystems:
1754 serving files into and out of a database, for example.
1755 The current manual page contains information about the hooks in
1757 "Net::FTPServer" which may be overridden.
1758 See Net::FTPServer::DirHandle(3) for information about the methods in
1760 "Net::FTPServer::DirHandle" which may be overridden.
1761 See Net::FTPServer::FileHandle(3) for information about the methods in
1763 "Net::FTPServer::FileHandle" which may be overridden.
1764 The most reasonable way to create your own personality is to extend one
1766 of the existing personalities. Choose the one which most closely
1767 matches the personality that you want to create. For example, suppose
1768 that you want to create another database personality. A good place to
1769 start would be by copying "lib/Net/FTPServer/DBeg1/*.pm" to a new
1770 directory "lib/Net/FTPServer/MyDB/" (for example). Now edit these files
1771 and substitute "MyDB" for "DBeg1". Then examine each subroutine in
1772 these files and modify them, consulting the appropriate manual page if
1773 you need to.
1774 VIRTUAL HOSTS
1776 "Net:FTPServer" is capable of hosting multiple FTP sites on a single
1777 machine. Because of the nature of the FTP protocol, virtual hosting is
1778 almost always done by allocating a single separate IP address per FTP
1779 site. However, "Net::FTPServer" also supports an experimental IP-less
1780 virtual hosting system, although this requires modifications to the
1781 client.
1782 Normal (IP-based) virtual hosting is carried out as follows:
1784 * For each FTP site, allocate a separate IP address.
1786 * Configure IP aliasing on your normal interface so that
1787 the single physical interface responds to multiple
1788 virtual IP addresses.
1789 * Add entries (A records) in DNS mapping each site's
1790 name to a separate IP address.
1791 * Add reverse entries (PTR records) in DNS mapping each
1792 IP address back to the site hostname. It is important
1793 that both forward and reverse DNS is set up correctly,
1794 else virtual hosting may not work.
1795 * In /etc/ftpd.conf you will need to add a virtual host
1796 section for each site like this:
1797 <Host sitename>
1799 ip: 1.2.3.4
1801 ... any specific configuration options for this site ...
1802 </Host>
1804 You don't in fact need the "ip:" part assuming that
1806 your forward and reverse DNS are set up correctly.
1807 * If you want to specify a lot of external sites, or
1808 generate the configuration file automatically from a
1809 database or a script, you may find the <Include filename>
1810 syntax useful.
1811 There are examples in "/etc/ftpd.conf". Here is how IP-based virtual
1813 hosting works:
1814 * The server starts by listening on all interfaces.
1816 * A connection arrives at one of the IP addresses and a
1817 process is forked off.
1818 * The child process finds out which interface the
1819 client connected to and reverses the name.
1820 * If:
1821 the IP address matches one of the "ip:" declarations
1822 in any of the "Host" sections,
1823 or:
1824 there is a reversal for the name, and the name
1825 matches one of the "Host" sections in the configuration
1826 file,
1827 then:
1828 configuration options are read from that
1829 section of the file and override any global configuration
1830 options specified elsewhere in the file.
1831 * Otherwise, the global configuration options only
1832 are used.
1833 IP-less virtual hosting is an experimental feature. It requires the
1835 client to send a "HOST" command very early on in the command stream --
1836 before "USER" and "PASS". The "HOST" command explicitly gives the
1837 hostname that the FTP client is attempting to connect to, and so allows
1838 many FTP sites to be multiplexed onto a single IP address. At the
1839 present time, I am not aware of any FTP clients which implement the
1840 "HOST" command, although they will undoubtedly become more common in
1841 future.
1842 This is how to set up IP-less virtual hosting:
1844 * Add entries (A or CNAME records) in DNS mapping the
1846 name of each site to a single IP address.
1847 * In /etc/ftpd.conf you will need to list the same single
1848 IP address to which all your sites map:
1849 virtual host multiplex: 1.2.3.4
1851 * In /etc/ftpd.conf you will need to add a virtual host
1853 section for each site like this:
1854 <Host sitename>
1856 ... any specific configuration options for this site ...
1858 </Host>
1860 Here is how IP-less virtual hosting works:
1862 * The server starts by listening on one interface.
1864 * A connection arrives at the IP address and a
1865 process is forked off.
1866 * The IP address matches "virtual host multiplex"
1867 and so no IP-based virtual host processing is done.
1868 * One of the first commands that the client sends is
1869 "HOST" followed by the hostname of the site.
1870 * If there is a matching "Host" section in the
1871 configuration file, then configuration options are
1872 read from that section of the file and override any
1873 global configuration options specified elsewhere in
1874 the file.
1875 * If there is no matching "Host" section then the
1876 global configuration options alone are used.
1877 The client is not permitted to issue the "HOST" command more than once,
1879 and is not permitted to issue it after login.
1880 VIRTUAL HOSTING AND SECURITY
1882 Only certain configuration options are available inside the <Host>
1883 sections of the configuration file. Generally speaking, the only
1884 configuration options you can put here are ones which take effect after
1885 the site name has been determined -- hence "allow anonymous" is OK
1886 (since it's an option which is parsed after determining the site name
1887 and during log in), but "port" is not (since it is parsed long before
1888 any clients ever connect).
1889 Make sure your default global configuration is secure. If you are using
1891 IP-less virtual hosting, this is particularly important, since if the
1892 client never sends a "HOST" command, the client gets the global
1893 configuration. Even with IP-based virtual hosting it may be possible
1894 for clients to sometimes get the global configuration, for example if
1895 your local name server fails.
1896 IP-based virtual hosting always takes precedence above IP-less virtual
1898 hosting.
1899 With IP-less virtual hosting, access control cannot be performed on a
1901 per-site basis. This is because the client has to issue commands (ie.
1902 the "HOST" command at least) before the site name is known to the
1903 server. However you may still have a global "access control rule".
1904 ARCHIVE MODE
1906 Beginning with version 1.100, "Net::FTPServer" is able to generate
1907 certain types of compressed and archived files on the fly. In practice
1908 what this means is that if a user requests, say, "file.gz" and this
1909 file does not actually exist (but "file" does exist), then the server
1910 will dynamically generate a gzip-compressed version of "file" for the
1911 user. This also works on directories, so that a user might request
1912 "dir.tar.gz" which does not exist (but directory "dir" does exist), and
1913 the server tars up and compresses the entire contents of "dir" and
1914 presents that back to the user.
1915 Archive mode is enabled by default. However, it will not work unless
1917 you substantially increase the per-process memory, processes and files
1918 limits. The reason for this is that archive mode works by forking
1919 external programs such as "gzip" to perform the compression. For the
1920 same reason you may also need to ensure that at least "gzip",
1921 "compress", "bzip2" and "uuencode" programs are available on the
1922 current $PATH, particularly if you are using a chrooted environment.
1923 To disable archive mode put "enable archive mode: 0" into the
1925 configuration file.
1926 The following file extensions are supported:
1928 .gz GZip compressed. Requires gzip program on PATH.
1930 .Z Unix compressed. Requires compress program on PATH.
1931 .bz2 BZip2 compressed. Requires bzip2 program on PATH.
1932 .uue UU-encoded. Requires uuencode program on PATH.
1933 .tar Tar archive. Requires Perl Archive::Tar module.
1934 .zip DOS ZIP archive. Requires Perl Archive::Zip module.
1935 .list Return a list of all the files in this directory.
1936 File extensions may be combined. Hence ".tar.gz", ".tar.bz2" and even
1938 ".tar.gz.uue" will all work as you expect.
1939 Archive mode is, of course, extensible. It is particularly simple to
1941 add another compression / filter format. In your personality (or in a
1942 <Perl> section in the configuration file) you need to add another key
1943 to the "archive_filters" hash.
1944 $ftps->{archive_filters}{".foo"} = &_foo_filter;
1946 The value of this key should be a function as defined below:
1948 \%filter = _foo_filter ($ftps, $sock);
1950 The filter should return a hash reference (undef if it fails). The
1952 hash should contain the following keys:
1953 sock Newly opened socket.
1955 pid PID of filter program.
1956 The "_foo_filter" function takes the existing socket and filters it,
1958 providing a new socket which the FTP server will write to (for the data
1959 connection back to the client). If your filter is a Unix program, then
1960 the simplest thing is just to define "_foo_filter" as:
1961 sub _foo_filter
1963 {
1964 return $_[0]->archive_filter_external ($_[1], "foo" [, args ...]);
1965 }
1966 The "archive_filter_external" function takes care of the tricky bits
1968 for you.
1969 Adding new generators (akin to the existing tar and ZIP) is more
1971 tricky. I suggest you look closely at the code and consult the author
1972 for more information.
1973
1975 Net::FTPServer->run ([\@ARGV]);
1976 This is the main entry point into the FTP server. It starts the FTP
1978 server running. This function never normally returns.
1979 If no arguments are given, then command line arguments are taken
1981 from the global @ARGV array.
1982 $regex = $ftps->wildcard_to_regex ($wildcard)
1984 This is a general library function shared between many of the back-
1986 end database personalities. It converts a general wildcard (eg.
1987 *.c) into a regular expression (eg. ^.*\.c$ ).
1988 Thanks to: Terrence Monroe Brannon <terrence.brannon@oracle.com>.
1990 $regex = $ftps->wildcard_to_sql_like ($wildcard)
1992 This is a general library function shared between many of the back-
1994 end database personalities. It converts a general wildcard (eg.
1995 *.c) into the strange wildcardish format used by SQL LIKE operator
1996 (eg. %.c).
1997 $ftps->reply ($code, $line, [$line, ...])
1999 This function sends a standard single line or multi-line FTP server
2001 reply to the client. The $code should be one of the standard reply
2002 codes listed in RFC 959. The one or more $line arguments are the
2003 (free text) of the reply. Do not include carriage returns at the
2004 end of each $line. This function adds the correct line ending
2005 format as specified in the RFC.
2006 $ftps->log ($level, $message, ...);
2008 This function is identical to the normal "syslog" function to be
2010 found in "Sys::Syslog". However, it only uses syslog if the "enable
2011 syslog" configuration option is set to true.
2012 Use this function instead of calling "syslog" directly.
2014 $ftps->config ($name);
2016 Read configuration option $name from the configuration file.
2018 $ftps->ip_host_config ($ip_addr);
2020 Look for a <Host> section which contains "ip: $ip_addr". If one is
2022 found, return the site name of the Host section. Otherwise return
2023 undef.
2024 $filter = $ftps->archive_filter_external ($sock, $cmd [, $args]);
2026 Apply $cmd as a filter to socket $sock. Returns a hash reference
2028 which contains the following keys:
2029 sock Newly opened socket.
2031 pid PID of filter program.
2032 If it fails, returns "undef".
2034 See section ARCHIVE MODE elsewhere in this manual for more
2036 information.
2037 $ftps->visit ($dirh, \%functions);
2039 The "visit" function recursively "visits" every file and directory
2041 contained in $dirh (which must be a directory handle).
2042 "\%functions" is a reference to a hash of file types to functions.
2044 For example:
2045 'f' => \&visit_file,
2047 'd' => \&visit_directory,
2048 'l' => \&visit_symlink,
2049 &c.
2050 When a file of the known type is encountered, the appropriate
2052 function is called with $_ set to the file handle. (All functions
2053 are optional: if "visit" encounters a file with a type not listed
2054 in the %functions hash, then that file is just ignored).
2055 The return value from functions is ignored, except for the return
2057 value from the directory ('d') function. The directory function
2058 should return 1 to indicate that "visit" should recurse into that
2059 directory. If the directory function returns 0, then "visit" will
2060 skip that directory.
2061 "visit" will call the directory function once for $dirh.
2063 $sock = $self->open_data_connection;
2065 Open a data connection. Returns the socket (an instance of
2067 "IO::Socket") or undef if it fails for some reason.
2068 $self->pre_configuration_hook ();
2070 Hook: Called before command line arguments and configuration file
2072 are read.
2073 Status: optional.
2075 Notes: You may append your own information to
2077 "$self->{version_string}" from this hook.
2078 $self->options_hook (\@args);
2080 Hook: Called before command line arguments are parsed.
2082 Status: optional.
2084 Notes: You can use this hook to supply your own command line
2086 arguments. If you parse any arguments, you should remove them from
2087 the @args array.
2088 $self->post_configuration_hook ();
2090 Hook: Called after all command line arguments and configuration
2092 file have been read and parsed.
2093 Status: optional.
2095 $self->post_bind_hook ();
2097 Hook: Called only in daemon mode after the control port is bound
2099 but before starting the accept infinite loop block.
2100 Status: optional.
2102 $self->pre_accept_hook ();
2104 Hook: Called in daemon mode only just before accept(2) is called in
2106 the parent FTP server process.
2107 Status: optional.
2109 $self->post_accept_hook ();
2111 Hook: Called both in daemon mode and in inetd mode just after the
2113 connection has been accepted. This is called in the child process.
2114 Status: optional.
2116 $rv = $self->access_control_hook;
2118 Hook: Called after accept(2)-ing the connection to perform access
2120 control. Detailed request information is contained in the $self
2121 object. If the function returns -1 then the socket is immediately
2122 closed and no FTP processing happens on it. If the function returns
2123 0, then normal access control is performed on the socket before FTP
2124 processing starts. If the function returns 1, then normal access
2125 control is not performed on the socket and FTP processing begins
2126 immediately.
2127 Status: optional.
2129 $rv = $self->process_limits_hook;
2131 Hook: Called after accept(2)-ing the connection to perform per-
2133 process limits (eg. by using the setrlimit(2) system call). Access
2134 control has already been performed and detailed request information
2135 is contained in the $self object.
2136 If the function returns -1 then the socket is immediately closed
2138 and no FTP processing happens on it. If the function returns 0,
2139 then normal per-process limits are applied before any FTP
2140 processing starts. If the function returns 1, then normal per-
2141 process limits are not performed and FTP processing begins
2142 immediately.
2143 Status: optional.
2145 $rv = $self->authentication_hook ($user, $pass, $user_is_anon)
2147 Hook: Called to perform authentication. If the authentication
2149 succeeds, this should return 0 (or any positive integer >= 0). If
2150 the authentication fails, this should return -1.
2151 Status: required.
2153 $self->user_login_hook ($user, $user_is_anon)
2155 Hook: Called just after user $user has successfully logged in. A
2157 good place to change uid and chroot if necessary.
2158 Status: optional.
2160 $dirh = $self->root_directory_hook;
2162 Hook: Return an instance of a subclass of Net::FTPServer::DirHandle
2164 corresponding to the root directory.
2165 Status: required.
2167 $self->pre_command_hook;
2169 Hook: This hook is called just before the server begins to wait for
2171 the client to issue the next command over the control connection.
2172 Status: optional.
2174 $rv = $self->command_filter_hook ($cmdline);
2176 Hook: This hook is called immediately after the client issues
2178 command $cmdline, but before any checking or processing is
2179 performed on the command. If this function returns -1, then the
2180 server immediately goes back to waiting for the next command. If
2181 this function returns 0, then normal command filtering is carried
2182 out and the command is processed. If this function returns 1 then
2183 normal command filtering is not performed and the command
2184 processing begins immediately.
2185 Important Note: This hook must be careful not to overwrite the
2187 global $_ variable.
2188 Do not use this function to add your own commands. Instead use the
2190 "$self->{command_table}" and "$self->{site_command_table}" hashes.
2191 Status: optional.
2193 $error = $self->transfer_hook ($mode, $file, $sock, \$buffer);
2195 $mode - Open mode on the File object (Either reading or writing)
2197 $file - File object as returned from DirHandle::open
2198 $sock - Data IO::Socket object used for transfering
2199 \$buffer - Reference to current buffer about to be written
2200 The \$buffer is passed by reference to minimize the stack overhead
2202 for efficiency purposes only. It is not meant to be modified by
2203 the transfer_hook subroutine. (It can cause corruption if the
2204 length of $buffer is modified.)
2205 Hook: This hook is called after reading $buffer and before writing
2207 $buffer to its destination. If arg1 is "r", $buffer was read from
2208 the File object and written to the Data socket. If arg1 is "w",
2209 $buffer will be written to the File object because it was read from
2210 the Data Socket. The return value is the error for not being able
2211 to perform the write. Return undef to avoid aborting the transfer
2212 process.
2213 Status: optional.
2215 $self->post_command_hook ($cmd, $rest)
2217 Hook: This hook is called after all command processing has been
2219 carried out on this command. $cmd is the command, and $rest is the
2220 remainder of the command line.
2221 Status: optional.
2223 $self->system_error_hook
2225 Hook: This hook is used instead of $! when what looks like a system
2227 error occurs during a virtual filesystem handle method. It can be
2228 used by the virtual filesystem to provide explanatory text for a
2229 virtual filesystem failure which did not actually set the real $!.
2230 Status: optional.
2232 $self->quit_hook
2234 Hook: This hook is called after the user has "QUIT" or if the FTP
2236 client cleanly drops the connection. Please note, however, that
2237 this hook is not called whenever the FTP server exits, particularly
2238 in cases such as:
2239 * The FTP server, the Perl interpreter or the personality
2241 crashes unexpectedly.
2242 * The user fails to log in.
2243 * The FTP server detects a fatal error, sends a "421" error code,
2244 and abruptly exits.
2245 * Idle timeouts.
2246 * Access control violations.
2247 * Manual server shutdowns.
2248 Unfortunately it is not in general easily possible to catch these
2250 cases and cleanly call a hook. If your personality needs to do
2251 cleanup in all cases, then it is probably better to use an "END"
2252 block inside your Server object (see perlmod(3)). Even using an
2253 "END" block cannot catch cases where the Perl interpreter crashes.
2254 Status: optional.
2256
2258 The SIZE, REST and RETR commands probably do not work correctly in
2259 ASCII mode.
2260 REST does not work before STOR/STOU/APPE (is it supposed to?)
2262 User upload/download limits.
2264 Limit number of clients by host or IP address.
2266 The following commands are recognized by "wu-ftpd", but are not yet
2268 implemented by "Net::FTPServer":
2269 SITE CHMOD There is a problem supporting this with our VFS.
2271 SITE GPASS Group functions are not really relevant for us.
2272 SITE GROUP -"- ditto -"-
2273 SITE GROUPS -"- ditto -"-
2274 SITE INDEX This is a synonym for SITE EXEC.
2275 SITE MINFO This command is no longer supported by wu-ftpd.
2276 SITE NEWER This command is no longer supported by wu-ftpd.
2277 SITE UMASK This command is difficult to support with VFS.
2278 Symbolic links are not handled elegantly (or indeed at all) yet.
2280 Equivalent of ProFTPD's ``DisplayReadme'' function.
2282 The ability to hide dot files (probably best to build this into the VFS
2284 layer). This should apply across all commands. See ProFTPD's
2285 ``IgnoreHidden'' function.
2286 Access to LDAP authentication database (can currently be done using a
2288 PAM module). In general, we should support pluggable authentication.
2289 Log formatting similar to ProFTPD command LogFormat.
2291 More timeouts to avoid various denial of service attacks. For example,
2293 the server should always timeout when waiting too long for an active
2294 data connection.
2295 Support for IPv6 (see RFC 2428), EPRT, EPSV commands.
2297 See also "XXX" comments in the code for other problems, missing
2299 features and bugs.
2300
2302 /etc/ftpd.conf
2303 /usr/lib/perl5/site_perl/5.005/Net/FTPServer.pm
2304 /usr/lib/perl5/site_perl/5.005/Net/FTPServer/DirHandle.pm
2305 /usr/lib/perl5/site_perl/5.005/Net/FTPServer/FileHandle.pm
2306 /usr/lib/perl5/site_perl/5.005/Net/FTPServer/Handle.pm
2307
2309 Richard Jones (rich@annexia.org), Rob Brown (bbb@cpan.org), Keith
2310 Turner (keitht at silvaco.com), Azazel (azazel at azazel.net), and many
2311 others.
2312
2314 Copyright (C) 2000 Biblio@Tech Ltd., Unit 2-3, 50 Carnwath Road,
2315 London, SW6 3EG, UK.
2316 Copyright (C) 2000-2003 Richard Jones (rich@annexia.org) and other
2318 contributors.
2319 This program is free software; you can redistribute it and/or modify it
2321 under the terms of the GNU General Public License as published by the
2322 Free Software Foundation; either version 2 of the License, or (at your
2323 option) any later version.
2324 This program is distributed in the hope that it will be useful, but
2326 WITHOUT ANY WARRANTY; without even the implied warranty of
2327 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
2328 General Public License for more details.
2329 You should have received a copy of the GNU General Public License along
2331 with this program; if not, write to the Free Software Foundation, Inc.,
2332 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
2333
2335 Net::FTPServer::Handle(3), Net::FTPServer::FileHandle(3),
2336 Net::FTPServer::DirHandle(3), Net::FTP(3), perl(1), RFC 765, RFC 959,
2337 RFC 1579, RFC 2389, RFC 2428, RFC 2577, RFC 2640, Extensions to FTP
2338 Internet Draft draft-ietf-ftpext-mlst-NN.txt.
2339
2341 Hey! The above document had some coding errors, which are explained
2342 below:
2343 Around line 1590:
2345 =back doesn't take any parameters, but you said =back 4
2346 Around line 2129:
2348 You can't have =items (as at line 2241) unless the first thing
2349 after the =over is an =item
2350 Around line 8193:
2352 =back doesn't take any parameters, but you said =back 4
2353perl v5.12.0 2010-05-04 Net::FTPServer(3)