所以在传输大量文件时，我们有时候不得不回头来寻找ftp服务器，我们在以前的帖子里已经探讨了怎样在OpenBSD的环境里搭建pure-ftpd服务器，有些朋友可能觉得有些繁琐，可能就是个人需要传送一些文件，并非对外提供服务。
实际上OpenBSD基本系统已经带有ftp服务器，但是默认情况下并未开启，你只要设置一下就可以了，如果在一段时间内需要FTP服务器的服务，编辑/etc/rc.conf.local文件，加上一句(任务结束后别忘了关闭——可以先将这行注释掉，留着下次使用。)：
代码: 全选
ftpd_flags="-DllUSA"代码: 全选
/usr/libexec/ftpd -DllUSA还有一些其它参数，关于具体的参数，请查阅用户手册：
经实际上测试，千M网卡(廉价的8169)之间的传输速度最快可以到达总线或硬盘速度的极限，我这里新机器之间可以到60M/s，就连老的dell GX400的FTP传输速度也可以到达25M/s（应该是总线的限制吧）。
我们这里仅提供一般性的方法，请根据自己的情况调整。主要注意，用户名不能包含在 /etc/ftpusers 文件内，在这个文件里的用户会被拒绝登录.
============================================================
如果你的ftp并不对外而是自用，或者换句话说，你的PF只允许你相信的内网用户（或者只有你自己)访问FTP服务器，那么上面的设定问题不大，但是如果你的FTP服务器还对外服务的话，上面的设定就很不安全了，你还需要进行其它的设置：
正常的登录用户必须包含在/etc/ftpchroot里，这个文件里的用户会被chroot在自己的目录内。
我们下面说说对外服务的ftp的设置：
匿名帐号的设置
我们假设你要提供匿名账号anonymous和专用帐号给外网用户使用，那么你需要做以下事情：
1. 在你设置ftp帐号前需要先配置shell, 也就是给ftp用户分配一个不能访问控制台的shell，我们这里为其分配 /usr/bin/false, /usr/bin/false是一个sh脚本，我们看一下这个脚本的内容：
代码: 全选
# cat /usr/bin/false
#! /bin/sh
# $OpenBSD: false.sh,v 1.2 1996/06/26 05:32:50 deraadt Exp $
exit 1
#
这个脚本在默认安装时已经有了，但是并未包含在 /etc/shells这个文件里。我们先看一下这个文件：
代码: 全选
# cat /etc/shells
# $OpenBSD: shells,v 1.8 2009/02/14 17:06:40 sobrado Exp $
#
# list of acceptable shells for chpass(1).
# ftpd(8) will not allow users to connect who are not using
# one of these shells, unless the user is listed in /etc/ftpchroot.
/bin/sh
/bin/csh
/bin/ksh
#代码: 全选
# /usr/bin/false >> /etc/shells调整后的文件像这样：
代码: 全选
# cat /etc/shells
# $OpenBSD: shells,v 1.8 2009/02/14 17:06:40 sobrado Exp $
#
# list of acceptable shells for chpass(1).
# ftpd(8) will not allow users to connect who are not using
# one of these shells, unless the user is listed in /etc/ftpchroot.
/bin/sh
/bin/csh
/bin/ksh
[B][color=red]/usr/bin/false[/color][/B]
#
2. 创建匿名帐号
OpenBSD默认不存在匿名用户，我们要创建一个：
代码: 全选
# adduser
Use option ``-silent'' if you don't want to see all warnings and questions.
Reading /etc/shells
Check /etc/master.passwd
Check /etc/group
Ok, let's go.
Don't worry about mistakes. There will be a chance later to correct any input.
Enter username []: [B][color=royalblue]ftp[/color][/B]
Enter full name []: [B][color=royalblue]anonymous ftp[/color][/B]
Enter shell csh false ksh nologin sh [ksh]: [B][color=royalblue]false[/color][/B]
Uid [1002]: [color=royalblue][B][I]enter[/I][/B][/color]
Login group ftp [ftp]: [color=royalblue][B][I]enter[/I][/B][/color]
Login group is ``ftp''. Invite ftp into other groups: guest no
[no]: [color=royalblue][B][I]enter[/I][/B][/color]
Login class authpf daemon default mysql staff [default]: [color=royalblue][B][I]enter[/I][/B][/color]
Enter password []: [color=royalblue][B][I]enter[/I][/B][/color]
Set the password so that user cannot logon? (y/n) [n]: [color=royalblue][B]y[/B][/color]
Name: ftp
Password: ****
Fullname: anonymous ftp
Uid: 1002
Gid: 1002 (ftp)
Groups: ftp
Login Class: default
HOME: /home/ftp
Shell: /usr/bin/false
OK? (y/n) [y]: [color=royalblue][B][I]enter[/I][/B][/color]
Added user ``ftp''
Copy files from /etc/skel to /home/ftp
Add another user? (y/n) [y]: [B][color=royalblue]n[/color][/B]
Goodbye!
#
3. 设置权限
这个 /home/ftp 目录必须属于root, 且属性必须为555，我们在里面再设置一个对外服务目录pub, 在 pub 下再设置两个子目录 download 和 upload 分别放置上传和下载的资源。
代码: 全选
# mkdir -p /home/ftp/pub/upload
# mkdir -p /home/ftp/pub/download
# chown -R root:wheel /home/ftp
# chmod -R 555 /home/ftp
代码: 全选
chmod -R 773 /home/ftp/pub/upload
用户上传完毕后，可以通知管理员将upload目录内传完内容移到download目录下公开下载。——实际不用通知，在每个上传的目录内加上一个目录@done就可以了表示已经传完了。:)
到这里匿名用户的配置基本上就结束了，因为你多半也不会给这个用户太多的权限。此外需要说明的是这个匿名用户ftp你不用设置在/etc/ftpchroot 文件内，因为系统已经禁止其随意溜达了。:cool:
剩下的就是建立一个 /etc/ftpwelcome 文件，在里面写入欢迎信息。
下面我们再说一下，系统内普通用户的设置：
4.8里非匿名用户的username必须加入到ftpchroot里，否则系统会拒绝其登录。
（未完待续！）
这里附上ftpd用户手册：
代码: 全选
# man ftpd
FTPD(8) OpenBSD System Manager's Manual FTPD(8)
NAME
ftpd - Internet File Transfer Protocol server
SYNOPSIS
ftpd [-46ADdlMnPSU] [-T maxtimeout] [-t timeout] [-u mask]
DESCRIPTION
ftpd is the Internet File Transfer Protocol server process. The server
uses the TCP protocol and listens at the port specified in the ``ftp''
service specification; see services(5).
The options are as follows:
-4 When -D is specified, forces ftpd to use IPv4 addresses only.
-6 When -D is specified, forces ftpd to use IPv6 addresses only.
-A Permit only anonymous FTP connections (unless the -n option is
specified), accounts listed in /etc/ftpchroot or users in a login
class with the ``ftp-chroot'' variable set (see below). Other
connection attempts are refused.
-D With this option set, ftpd will detach and become a daemon,
accepting connections on the FTP port and forking child processes
to handle them. This has lower overhead than starting ftpd from
inetd(8) and is thus useful on busy servers to reduce load.
-d Debugging information is written to the syslog using LOG_FTP.
-l Each successful and failed FTP session is logged using syslog
with a facility of LOG_FTP. If this option is specified twice,
the retrieve (get), store (put), append, delete, make directory,
remove directory and rename operations and their filename
arguments are also logged.
-M Enables multihomed mode. Instead of simply using ~ftp for
anonymous transfers, a directory matching the fully qualified
name of the IP number the client connected to, and located inside
~ftp, is used instead.
-n Do not permit anonymous FTP logins. Normally they are permitted.
-P Permit illegal port numbers or addresses for PORT command
initiated connects. By default ftpd violates the RFC and thus
constrains the PORT command to non-reserved ports and requires it
use the same source address as the connection came from. This
prevents the "FTP bounce attack" against services on both the
local machine and other local machines.
-S With this option set, ftpd logs all anonymous downloads to the
file /var/log/ftpd when this file exists.
-T maxtimeout
A client may also request a different timeout period; the maximum
period allowed may be set to maxtimeout seconds with the -T
option. The default limit is 2 hours.
-t timeout
The inactivity timeout period is set to timeout seconds (the
default is 15 minutes).
-U Each concurrent FTP session is logged to the file /var/run/utmp,
making them visible to commands such as who(1).
-u mask
Force the umask to mask, instead of the default specified in
/etc/login.conf (usually 022). Also disallows chmod.
The file /etc/nologin can be used to disable FTP access. If the file
exists, ftpd displays it and exits. Note: this method will disable all
non-root logins; see login(1) for further details. If the file
/etc/ftpwelcome exists, ftpd prints it before issuing the ``ready''
message. If the welcome file exists (/etc/motd by default), ftpd prints
it after a successful login. If the file .message exists in a directory,
ftpd prints it when that directory is entered.
The FTP server currently supports the following FTP requests. The case
of the requests is ignored.
Request Description
ABOR abort previous command
ACCT specify account (not implemented)
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
EPRT specify data connection port
EPSV prepare for server-to-server transfer
HELP give help information
LIST give list of files in a directory (ls -lgA)
LPRT specify data connection port
LPSV prepare for server-to-server transfer
MDTM show last modification time of file
MKD make a directory
MODE specify data transfer mode
NLST give name list of files in directory
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
REIN reinitialize (not implemented)
REST restart incomplete transfer
RETR retrieve a file
RMD remove a directory
RNFR specify rename-from file name
RNTO specify rename-to file name
SITE non-standard commands (see next section)
SIZE return size of file
SMNT structure mount (not implemented)
STAT return status of server
STOR store a file
STOU store a file with a unique name
STRU specify data transfer structure
SYST show operating system type of server system
TYPE specify data transfer type
USER specify user name; not valid after login
XCUP change to parent of current working directory (deprec.)
XCWD change working directory (deprecated)
XMKD make a directory (deprecated)
XPWD print the current working directory (deprecated)
XRMD remove a directory (deprecated)
The following non-standard or UNIX specific commands are supported by the
SITE request:
Request Description
CHMOD change mode of a file, e.g., SITE CHMOD 755 filename
HELP give help information
IDLE set idle-timer, e.g., SITE IDLE 60
UMASK change umask, e.g., SITE UMASK 002
The remaining FTP requests specified in Internet RFC 959 are recognized,
but not implemented. MDTM and SIZE are not specified in RFC 959, but
will appear in the next updated FTP RFC.
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. If a STAT command is received during a data transfer,
preceded by a Telnet IP and Synch, transfer status will be returned.
ftpd interprets file names according to the ``globbing'' conventions used
by csh(1). This allows users to utilize the metacharacters ``*?[]{}~''.
ftpd authenticates users by using the service and type of ftp, as defined
in the /etc/login.conf file (see login.conf(5)). An authentication style
may be specified by appending with a colon (`:') following the
authentication style, i.e. ``joe:skey''. The allowed authentication
styles for ftpd may be explicitly specified by the ``auth-ftp'' entry in
/etc/login.conf.
ftpd authenticates users according to five rules.
1. The login 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 login name must not appear in the file /etc/ftpusers.
3. The user must have a standard shell as described by shells(5).
4. If the user name appears in the file /etc/ftpchroot, the
session's root will be changed to the user's login directory
by chroot(2) as for an ``anonymous'' or ``ftp'' account (see
next item). However, the user must still supply a password.
This feature is intended as a compromise between a fully
anonymous account and a fully privileged account. The account
should also be set up as for an anonymous account.
5. 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 an email address for the user should
be used as the password).
Once a user is authenticated the user must be approved by any approval
script defined (see login.conf(5)). If a valid approval script (by
either :approve=...: or :approve-ftp=...: for the user's class) is
defined then it is run and must exit with a 0 (success) status. When
ftpd is running under the -D flag (and debugging is not turned on) then
the approval script will be called with at least the following variables
specified via the -v option (see login.conf(5)) to the approve script:
Variable Description
FTPD_HOST The server's (virtual) hostname
For example (the line is broken to fit the page):
/usr/libexec/auth/approve_ftpd -v FTPD_HOST=ftp.mycompany.com \
username class service
When the user logs in to the anonymous FTP account, ftpd takes special
measures to restrict the client's access privileges. The server performs
a chroot(2) 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, following these rules:
~ftp Make the home directory owned by ``root'' and unwritable
by anyone (mode 555).
~ftp/bin Make this directory owned by ``root'' and unwritable by
anyone (mode 511). This directory is optional unless you
have commands you wish the anonymous FTP user to be able
to run (the ls(1) command exists as a built-in). Any
programs in this directory should be mode 111 (executable
only).
~ftp/etc Make this directory owned by ``root'' and unwritable by
anyone (mode 511). The files pwd.db (see pwd_mkdb(8))
and group(5) must be present for the ls(1) command to be
able to produce owner names rather than numbers. The
password field in pwd.db is not used, and should not
contain real passwords. The file motd, if present, will
be printed after a successful login. These files should
be mode 444.
~ftp/pub Make this directory mode 555 and owned by ``root''. This
is traditionally where publicly accessible files are
stored for download.
If logging to the /var/log/ftpd file is enabled, information will be
written in the following format:
time The time and date of the download, in ctime(3)
format.
elapsed time The elapsed time, in seconds.
remote host The remote host (or IP number).
bytes The number of bytes transferred.
path The full path (relative to the FTP chroot space) of
the file transferred.
type The type of transfer; either `a' for ASCII or `b'
for binary.
unused Unused field containing a `*', for compatibility.
unused Unused field containing an `o', for compatibility.
user type The type of user; either `a' for anonymous or `r'
for a real user (should always be anonymous).
name Either a system login name or the value given for
``email address'' if an anonymous user.
unused Unused field containing a `0', for compatibility.
real name The system login name if the connection is not
anonymous, or a `*' if it is.
Although fields exist for logging information on real users, this file is
only used for anonymous downloads. Unused fields exist only for
compatibility with other ftpd implementations.
LOGIN.CONF VARIABLES
The ftpd daemon uses the following FTP-specific parameters:
auth-ftp The list of authentication types available to this class.
See login.conf(5).
ftp-chroot A boolean value. If set, users in this class will be
automatically chrooted to the user's login directory.
ftp-dir A path to a directory. This value overrides the login
directory for users in this class. A leading tilde (`~') in
ftp-dir will be expanded to the user's home directory based
on the contents of the password database.
welcome The path of the file containing the welcome message. If this
variable is not set, /etc/motd is used.
PORT ALLOCATION
For passive mode data connections, ftpd will listen to a random high TCP
port. The interval of ports used are configurable using sysctl(8)
variables net.inet.ip.porthifirst and net.inet.ip.porthilast.
FILES
/etc/ftpchroot list of normal users who should be chrooted
/etc/ftpusers list of unwelcome/restricted users
/etc/ftpwelcome welcome notice
/etc/login.conf authentication styles
/etc/motd printed after a successful login
/etc/nologin displayed and access refused
/var/log/ftpd log file for anonymous downloads
/var/run/ftpd.pid process ID if running in daemon mode
/var/run/utmp list of users on the system
SEE ALSO
ftp(1), login(1), skey(1), who(1), chroot(2), ctime(3), group(5),
login.conf(5), motd(5), services(5), shells(5), ftp-proxy(8), inetd(8),
pwd_mkdb(8), sysctl(8), syslogd(8)
HISTORY
The ftpd command appeared in 4.2BSD.
OpenBSD 4.8 May 31, 2007 OpenBSD 4.8