linux FTP配置詳解

linux FTP配置詳解 一.vsftpd說明: www.2cto.com LINUX下實現FTP服務的軟件很多,最常見的有vsftpd,Wu-ftpd和Proftp等.Red Hat Enterprise Linux中默認安裝的是vsftpd. 訪問FTP服務器時需要經過驗證,只有經過了FTP服務器的相關驗證,用戶才能訪問和傳輸文件.vsftpd提供了3種ftp登錄形式: (1)anonymous(匿名帳號) 使用anonymous是應用廣泛的一種FTP服務器.如果用戶在FTP服務器上沒有帳號,那麼用戶可以以anonymous為用戶名,以自己的電子郵件地址為密碼進行登錄.當匿名用戶登錄FTP服務器後,其登錄目錄為匿名FTP服務器的根目錄/var/ftp.為了減輕FTP服務器的負載,一般情況下,應關閉匿名帳號的上傳功能. (2)real(真實帳號) real也稱為本地帳號,就是以真實的用戶名和密碼進行登錄,但前提條件是用戶在FTP服務器上擁有自己的帳號.用真實帳號登錄後,其登錄的目錄為用戶自己的目錄,該目錄在系統建立帳號時系統就自動創建. (3)guest(虛擬帳號) 如果用戶在FTP服務器上擁有帳號,但此帳號只能用於文件傳輸服務,那麼該帳號就是guest,guest是真實帳號的一種形式,它們的不同之處在於,geust登錄FTP服務器後,不能訪問除宿主目錄以外的內容. 二.FTP相關配置文件說明 其相關配置文件有/etc/vsftpd/vsftpd.conf, /etc/vsftpd.ftpusers, /etc/vsftpd.user_list,在配置FTP服務器時,主要是修改這些文件中的相關語句. 1.vsftpd.conf文件說明 # Example config file /etc/vsftpd/vsftpd.conf # # The default compiled in settings are fairly paranoid. This sample file # loosens things up a bit, to make the ftp daemon more usable. # Please see vsftpd.conf.5 for all compiled in defaults. # # READ THIS: This example file is NOT an exhaustive list of vsftpd options. # Please read the vsftpd.conf.5 manual page to get a full idea of vsftpd's # capabilities. # # Allow anonymous FTP? (Beware - allowed by default if you comment this out). anonymous_enable=YES //是否允許anonymous登錄FTP服務器,默認是允許的. # # Uncomment this to allow local users to log in. local_enable=YES //是否允許本地用戶登錄FTP服務器,默認是允許 # # Uncomment this to enable any form of FTP write command. write_enable=YES //是否允許用戶具有在FTP服務器文件中執行寫的權限,默認是允許 # # Default umask for local users is 077. You may wish to change this to 022, # if your users expect that (022 is used by most other ftpd's) local_umask=022 //設置本地用戶的文件生成掩碼為022,默認是077 # # Uncomment this to allow the anonymous FTP user to upload files. This only # has an effect if the above global write enable is activated. Also, you will # obviously need to create a directory writable by the FTP user. #anon_upload_enable=YES # # Uncomment this if you want the anonymous FTP user to be able to create # new directories. #anon_mkdir_write_enable=YES //是否允許匿名賬戶在FTP服務器中創建目錄 # # Activate directory messages - messages given to remote users when they # go into a certain directory. dirmessage_enable=YES //激活目錄信息,當遠程用戶更改目錄時,將出現提示信息 # # Activate logging of uploads/downloads. xferlog_enable=YES //啟用上傳和下載日志功能 # # Make sure PORT transfer connections originate from port 20 (ftp-data). connect_from_port_20=YES //啟用FTP數據端口的連接請求 # # If you want, you can arrange for uploaded anonymous files to be owned by # a different user. Note! Using "root" for uploaded files is not # recommended! #chown_uploads=YES #chown_username=whoever # # You may override where the log file goes if you like. The default is shown # below. #xferlog_file=/var/log/vsftpd.log //設置日志文件的文件名和存儲路徑,這是默認的 # # If you want, you can have your log file in standard ftpd xferlog format xferlog_std_format=YES//是否使用標准的ftpd xferlog日志文件格式 # # You may change the default value for timing out an idle session. #idle_session_timeout=600 //設置空閒的用戶會話中斷時間,默認是10分鐘 # # You may change the default value for timing out a data connection. #data_connection_timeout=120//設置數據連接超時時間,默認是120秒. # # It is recommended that you define on your system a unique user which the # ftp server can use as a totally isolated and unprivileged user. #nopriv_user=ftpsecure # # Enable this and the server will recognise asynchronous ABOR requests. Not # recommended for security (the code is non-trivial). Not enabling it, # however, may confuse older FTP clients. #async_abor_enable=YES # # By default the server will pretend to allow ASCII mode but in fact ignore # the request. Turn on the below options to have the server actually do ASCII # mangling on files when in ASCII mode. # Beware that turning on ascii_download_enable enables malicious remote parties # to consume your I/O resources, by issuing the command "SIZE /big/file" in # ASCII mode. # These ASCII options are split into upload and download because you may wish # to enable ASCII uploads (to prevent uploaded scripts etc. from breaking), # without the DoS risk of SIZE and ASCII downloads. ASCII mangling should be # on the client anyway.. #ascii_upload_enable=YES #ascii_download_enable=YES //是否允許使用ASCII格式來上傳和下載文件 # # You may fully customise the login banner string: #ftpd_banner=Welcome to blah FTP service.//在FTP服務器中設置歡迎登錄的信息. # # You may specify a file of disallowed anonymous e-mail addresses. Apparently # useful for combatting certain DoS attacks. #deny_email_enable=YES # (default follows) #banned_email_file=/etc/vsftpd.banned_emails # # You may specify an explicit list of local users to chroot() to their home # directory. If chroot_local_user is YES, then this list becomes a list of # users to NOT chroot(). #chroot_list_enable=YES //如果希望用戶登錄後不能切換到自己目錄以外的其它目錄,需要設置該項,如果設置chroot_list_enable=YES,那麼只允許/etc/vsftpd.chroot_list中列出的用戶具有該功能.如果希望所有的本地用戶都執行者chroot,可以增加一行:chroot_local_user=YES # (default follows) #chroot_list_file=/etc/vsftpd.chroot_list # # You may activate the "-R" option to the builtin ls. This is disabled by # default to avoid remote users being able to cause excessive I/O on large # sites. However, some broken FTP clients such as "ncftp" and "mirror" assume # the presence of the "-R" option, so there is a strong case for enabling it. #ls_recurse_enable=YES pam_service_name=vsftpd //設置PAM認證服務的配置文件名稱,該文件存放在/etc/pam.d/目錄下. userlist_enable=YES //用戶列表中的用戶是否允許登錄FTP服務器,默認是不允許 #enable for standalone mode listen=YES //使vsftpd 處於獨立啟動模式 tcp_wrappers=YES //使用tcp_wrqppers作為主機訪問控制方式 2.vsftpd.ftpusers文件說明 這個文件是用來記錄"不允許"登錄到FTP服務器的用戶,通常是一些系統默認的用戶. 下面是該文件中默認的不允許登錄的名單: # Users that are not allowed to login via ftp root //默認情況下,root和它以下的用戶是不允許登錄FTP服務器的.可以將不允許登錄的用戶添加到這裡來.但切記每個用戶都要單獨占用一行. bin daemon adm lp sync shutdown halt mail news uucp operator games nobody 3.vsftpd.user_list文件說明 其實它的內容跟上面那個文件內容一樣,只是在系統對文件vsftpd.conf 進行檢測時,會檢測到"userlist_deny=YES",因此這個文件必須存在.下面是這個文件的內容. # vsftpd userlist # If userlist_deny=NO, only allow users in this file # If userlist_deny=YES (default), never allow users in this file, and # do not even prompt for a password. # Note that the default vsftpd pam config also checks /etc/vsftpd.ftpusers # for users that are denied. root bin daemon adm lp sync shutdown halt mail news uucp operator games nobody