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ftp常见错误

常见响应码

响应码 含义
110   重新启动标记应答
120   服务在指定时间内准备好 
125   数据连接打开,开始传输 
150   文件状态良好,将要打开数据连接 
200 命令成功
202   命令没有执行 
211  系统状态回复
212  目录状态回复  
213  文件状态回复
214 帮助信息回复
215  系统类型回复
220 服务就绪 
221  服务关闭控制连接,可以退出登录
225 数据连接打开,无传输正在进行
226  关闭数据连接,请求的文件操作成功
227  进入被动模式 
230  用户已经登录
250  请求的文件操作完成 请求文件操作终止,超过存储分配
257  创建路径名  
332  登录时需要账户信息
350  请求的文件操作需要进一步的口令
426  关闭连接,终止传输
450  文件不可用
451  中止请求操作,有本地错误
452  磁盘空间不足
500 权限过大
501  语法错误
502  命令未执行
503  命令顺序错误
504  无效命令参数
530 认证失败
532  存储文件需要账户信息
550 服务本身不允许
551  请求操作终止,页类型未知
553 文件系统权限过小

ftp的常见问题

匿名用户家目录的权限问题

ftp不能修改匿名用户的家目录,否则服务及时启动了,用户也登录不了,会出现下面的现象,输入完用户名,两次回车后,就卡着不动了。

 

 抓包可以看出 

[root@iZ8vb2hjg65famgbqjk1diZ ~]# tcpdump -nnn -i eth0 tcp port 21
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on eth0, link-type EN10MB (Ethernet), capture size 262144 bytes
19:40:49.683144 IP 114.249.135.195.27828 > 172.26.53.172.21: Flags [S], seq 3111604523, win 64240, options [mss 1412,nop,wscale 8,nop,nop,sackOK], length 0
19:40:49.683185 IP 172.26.53.172.21 > 114.249.135.195.27828: Flags [S.], seq 1886686711, ack 3111604524, win 29200, options [mss 1460,nop,nop,sackOK,nop,wscale 7], length 0
19:40:49.694527 IP 114.249.135.195.27828 > 172.26.53.172.21: Flags [.], ack 1, win 259, length 0
19:40:49.696843 IP 172.26.53.172.21 > 114.249.135.195.27828: Flags [P.], seq 1:21, ack 1, win 229, length 20: FTP: 220 (vsFTPd 3.0.3)
19:40:49.791142 IP 114.249.135.195.27828 > 172.26.53.172.21: Flags [.], ack 21, win 259, length 0
以上为建立命令连接时的三次握手的TCP报文

19:41:00.230394 IP 114.249.135.195.27828 > 172.26.53.172.21: Flags [P.], seq 1:11, ack 21, win 259, length 10: FTP: USER ftp
19:41:00.230422 IP 172.26.53.172.21 > 114.249.135.195.27828: Flags [.], ack 11, win 229, length 0
19:41:00.230646 IP 172.26.53.172.21 > 114.249.135.195.27828: Flags [P.], seq 21:55, ack 11, win 229, length 34: FTP: 331 Please specify the password.
19:41:00.286832 IP 114.249.135.195.27828 > 172.26.53.172.21: Flags [.], ack 55, win 259, length 0
以上为用户认证时的认证时的报文

19:41:05.782272 IP 114.249.135.195.27828 > 172.26.53.172.21: Flags [P.], seq 11:18, ack 55, win 259, length 7: FTP: PASS 
19:41:05.785501 IP 172.26.53.172.21 > 114.249.135.195.27828: Flags [P.], seq 55:65, ack 18, win 229, length 10: FTP: 500 OOPS: [!ftp]
19:41:05.785515 IP 172.26.53.172.21 > 114.249.135.195.27828: Flags [P.], seq 65:123, ack 18, win 229, length 58: FTP: vsftpd: refusing to run with writable root inside chroot()[!ftp]
19:41:05.785525 IP 172.26.53.172.21 > 114.249.135.195.27828: Flags [P.], seq 123:125, ack 18, win 229, length 2: FTP: 
19:41:05.785903 IP 172.26.53.172.21 > 114.249.135.195.27828: Flags [F.], seq 125, ack 18, win 229, length 0
19:41:05.803200 IP 114.249.135.195.27828 > 172.26.53.172.21: Flags [.], ack 65, win 258, options [nop,nop,sack 1 {123:125}], length 0
19:41:05.803219 IP 114.249.135.195.27828 > 172.26.53.172.21: Flags [.], ack 65, win 258, options [nop,nop,sack 1 {123:125}], length 0
19:41:05.808702 IP 172.26.53.172.21 > 114.249.135.195.27828: Flags [P.], seq 65:123, ack 18, win 229, length 58: FTP: vsftpd: refusing to run with writable root inside chroot()[!ftp]
19:41:06.037744 IP 172.26.53.172.21 > 114.249.135.195.27828: Flags [P.], seq 65:123, ack 18, win 229, length 58: FTP: vsftpd: refusing to run with writable root inside chroot()[!ftp]
19:41:06.493712 IP 172.26.53.172.21 > 114.249.135.195.27828: Flags [P.], seq 65:123, ack 18, win 229, length 58: FTP: vsftpd: refusing to run with writable root inside chroot()[!ftp]
19:41:07.437699 IP 172.26.53.172.21 > 114.249.135.195.27828: Flags [P.], seq 65:123, ack 18, win 229, length 58: FTP: vsftpd: refusing to run with writable root inside chroot()[!ftp]

修改pam认证也会造成输入完用户名密码就不动了

[root@iZzm446eh1ux98Z pam.d]# vim /etc/security/access.conf

-:zhang:ALL EXCEPT 121.89.165.3          ## 表示zhang用户访问ftp只能通过121.89.165.3这台服务器

修改pam

[root@iZzm446eh1ux98Z pam.d]# vim /etc/pam.d/vsftpd 
#%PAM-1.0
session    optional     pam_keyinit.so    force revoke
auth       required     pam_listfile.so item=user sense=deny file=/etc/vsftpd/ftpusers onerr=succeed
auth       required     pam_shells.so
auth       include      password-auth
account    required     pam_access.so      # 添加的内容
account    include      password-auth
session    required     pam_loginuid.so
session    include      password-auth

重启vsftpd

[root@iZzm446eh1ux98Z pam.d]# systemctl restart vsftpd

登录测试

[root@iZ8vb2hjg65famgbqjk1diZ vsftpd]# ftp 182.92.58.141
Connected to 182.92.58.141 (182.92.58.141).
220 (vsFTPd 3.0.2)
Name (182.92.58.141:root): zhang
331 Please specify the password.
Password:
230 Login successful.
Remote system type is UNIX.
Using binary mode to transfer files.

其他服务器就卡在哪里了

[root@ans1 ~]# ftp 182.92.58.141
Connected to 182.92.58.141 (182.92.58.141).
220 (vsFTPd 3.0.2)
Name (182.92.58.141:root): zhang
331 Please specify the password.
Password:


修改权限一般报错就是500 OOPS

[root@iZzm446eh1ux98Z pam.d]# ll /home/
total 4
drwxrwxrwx 2 zhang zhang 4096 May 16 19:04 zhang

登录的时候报错

[root@iZ8vb2hjg65famgbqjk1diZ vsftpd]# ftp 182.43.56.7
Connected to 182.43.56.7 (182.43.56.7).
220 (vsFTPd 3.0.2)
Name (182.43.56.7:root): zhang
331 Please specify the password.
Password:
500 OOPS: vsftpd: refusing to run with writable root inside chroot()
Login failed.
421 Service not available, remote server has closed connection

修改对应用户家目录权限即可

[root@iZzm446eh1ux98Z pam.d]# chmod 700 /home/zhang/
[root@iZzm446eh1ux98Z pam.d]# systemctl restart vsftpd

登录测试

[root@iZ8vb2hjg65famgbqjk1diZ vsftpd]# ftp 182.92.58.141
Connected to 182.92.58.141 (182.92.58.141).
220 (vsFTPd 3.0.2)
Name (182.92.58.141:root): zhang
331 Please specify the password.
Password:
230 Login successful.
Remote system type is UNIX.
Using binary mode to transfer files.

启动vsftpd的方法问题

使用vsftpd命令启动服务的时候,如果重启使用systemctl的unit脚本文件,会无法重启

[root@test ~]# vsftpd 
[root@test ~]# ss -lntp
State  Recv-Q  Send-Q    Local Address:Port   Peer Address:Port                                              
LISTEN 0       128             0.0.0.0:5355        0.0.0.0:*      users:(("systemd-resolve",pid=873,fd=13))  
LISTEN 0       128             0.0.0.0:22          0.0.0.0:*      users:(("sshd",pid=918,fd=5))              
LISTEN 0       128                [::]:5355           [::]:*      users:(("systemd-resolve",pid=873,fd=15))  
LISTEN 0       32                    *:21                *:*      users:(("vsftpd",pid=1396,fd=3))           
[root@test ~]# systemctl restart vsftpd
Job for vsftpd.service failed because the control process exited with error code.
See "systemctl status vsftpd.service" and "journalctl -xe" for details.

根据提示看了一下日志

Apr 15 20:57:38 test systemd[1]: Reloading.
Apr 15 20:57:42 test systemd[1]: Starting Vsftpd ftp daemon...
-- Subject: Unit vsftpd.service has begun start-up
-- Defined-By: systemd
-- Support: https://access.redhat.com/support
-- 
-- Unit vsftpd.service has begun starting up.
Apr 15 20:57:45 test systemd[1]: vsftpd.service: Control process exited, code=exited status=1
Apr 15 20:57:45 test systemd[1]: vsftpd.service: Failed with result 'exit-code'.
Apr 15 20:57:45 test systemd[1]: Failed to start Vsftpd ftp daemon.
-- Subject: Unit vsftpd.service has failed
-- Defined-By: systemd
-- Support: https://access.redhat.com/support
-- 
-- Unit vsftpd.service has failed.
-- 
-- The result is RESULT.

我猜想肯定是启动脚本的问题,看了一下unit文件

[root@test ~]# vim /usr/lib/systemd/system/vsftpd.service
[Unit]
Description=Vsftpd ftp daemon
After=network.target

[Service]
Type=forking
ExecStart=/usr/sbin/vsftpd /etc/vsftpd/vsftpd.conf

[Install]
WantedBy=multi-user.target

尝试用unit中的启动方式启动

[root@test ~]# /usr/sbin/vsftpd /etc/vsftpd/vsftpd.conf
[root@test ~]# ss -lntp
State  Recv-Q  Send-Q    Local Address:Port   Peer Address:Port                                              
LISTEN 0       128             0.0.0.0:5355        0.0.0.0:*      users:(("systemd-resolve",pid=873,fd=13))  
LISTEN 0       128             0.0.0.0:22          0.0.0.0:*      users:(("sshd",pid=918,fd=5))              
LISTEN 0       128                [::]:5355           [::]:*      users:(("systemd-resolve",pid=873,fd=15))  
LISTEN 0       32                    *:21                *:*      users:(("vsftpd",pid=1707,fd=3))     

再重启还是报错

[root@test ~]# systemctl restart vsftpd.service 
Job for vsftpd.service failed because the control process exited with error code.
See "systemctl status vsftpd.service" and "journalctl -xe" for details.

用unit文件启动就好使

[root@test ~]# systemctl start vsftpd.service 
[root@test ~]# ss -lntp
State  Recv-Q  Send-Q    Local Address:Port   Peer Address:Port                                              
LISTEN 0       128             0.0.0.0:5355        0.0.0.0:*      users:(("systemd-resolve",pid=873,fd=13))  
LISTEN 0       128             0.0.0.0:22          0.0.0.0:*      users:(("sshd",pid=918,fd=5))              
LISTEN 0       128                [::]:5355           [::]:*      users:(("systemd-resolve",pid=873,fd=15))  
LISTEN 0       32                    *:21                *:*      users:(("vsftpd",pid=1739,fd=3))           
[root@test ~]# systemctl restart vsftpd.service 
[root@test ~]# ss -lntp
State  Recv-Q  Send-Q    Local Address:Port   Peer Address:Port                                              
LISTEN 0       128             0.0.0.0:5355        0.0.0.0:*      users:(("systemd-resolve",pid=873,fd=13))  
LISTEN 0       128             0.0.0.0:22          0.0.0.0:*      users:(("sshd",pid=918,fd=5))              
LISTEN 0       128                [::]:5355           [::]:*      users:(("systemd-resolve",pid=873,fd=15))  
LISTEN 0       32                    *:21                *:*      users:(("vsftpd",pid=1767,fd=3))       

 与unit文件中的Type有关系

使用命令启动的时候只启动了一个进程

[root@node03 ~]# vsftpd 
[root@node03 ~]# ps -ef|grep ftp
root       1732      1  0 09:58 ?        00:00:00 vsftpd
root       1734   1366  0 09:58 pts/0    00:00:00 grep --color=auto ftp

使用unit启动的时候fork了子进程

[root@test ~]# ps -ef|grep ftp
root      2210     1  0 21:51 ?        00:00:00 /usr/sbin/vsftpd /etc/vsftpd/vsftpd.conf
nobody    2211  2210  0 21:51 ?        00:00:00 /usr/sbin/vsftpd /etc/vsftpd/vsftpd.conf
ftp       2213  2211  0 21:51 ?        00:00:00 /usr/sbin/vsftpd /etc/vsftpd/vsftpd.conf

 

posted on 2020-05-16 20:20  hopeless-dream  阅读(1281)  评论(0编辑  收藏  举报