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Blocking ftp users to connect using telnet

 
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# 1  
Old 02-23-2005
Question Blocking ftp users to connect using telnet
Hi everybody !

We have all flavors of Unix / Linux and we want to restrict ftp users to telnet our servers.

We can't disable telnet because we have other users using it.

Smilie Are there any thing that could be done to solve this thing ???

Best regards,
Julio Moreira
# 2  
Old 02-23-2005
I have a REDHAT box and configure users this way in passwd file. Users then have ftp access but no telnet access.

user:x:1001:1000:FTP User:/home/user:/sbin/nologin

By the way, never use telnet but use SSH.
# 3  
Old 02-23-2005
one other way:
go to the user's
".bash_profile" and adding in the line "exit" at the very end of the file.
It will act like it is starting a telnet session, then will drop them.

/home/username/.bash_profile is the path.
On the very last line type "exit", then save your changes.
# 4  
Old 02-23-2005
Quote:
Originally Posted by thumsup9
one other way:
go to the user's
".bash_profile" and adding in the line "exit" at the very end of the file.
It will act like it is starting a telnet session, then will drop them.

/home/username/.bash_profile is the path.
On the very last line type "exit", then save your changes.
But they can ftp in a new .profile and thus defeat this.

I like to use /bin/true and /bin/false for ftp shells. I put "true" in /etc/shells so a user with true can use ftp but cannot log in. If I want to lock them out of ftp as well, I can just switch the shell to "false".
# 5  
Old 02-23-2005
Quote:
Originally Posted by Perderabo
But they can ftp in a new .profile and thus defeat this.

I like to use /bin/true and /bin/false for ftp shells. I put "true" in /etc/shells so a user with true can use ftp but cannot log in. If I want to lock them out of ftp as well, I can just switch the shell to "false".
Good catch....don
# 6  
Old 02-24-2005
Quote:
Originally Posted by thumsup9
one other way:
go to the user's
".bash_profile" and adding in the line "exit" at the very end of the file.
It will act like it is starting a telnet session, then will drop them.

/home/username/.bash_profile is the path.
On the very last line type "exit", then save your changes.
Smilie That's a good idea, but what if we have a "global" .profile ?
# 7  
Old 02-24-2005
Computer I'll try it !!!
Quote:
Originally Posted by thumsup9
Good catch....don
Smilie That'd be great !!!!
 
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