Ftp/anonymous help

[Kathleen]

I am trying to figure out why I need an anonymous FTP login on my system. I wasn't concerned about this until one of my directories went up to 100% last night where the anonymous login could upload to. What function does this login serve? And if I remove it, what will it effect on the system? Sorry if this is a basic question....I am still learning this unix stuff. Thanks in advance.

[Rita C Workman · Accepted solution]

The 'anonymous' login is meant for an open ftp access system. It is usually set up so that anybody can get/put files on your system without a fixed password.
And obviously, they can put and put and put until a directory is filled if this is kept under control.
If you don't want this kind of 'OPEN' system than remove the anonymous or put anonymous entry in your ftpusers file to restrict it.

Just a quick thought,
Rita

[Sanjay_6]

Hi Kathleen,

Take a look at the threads below fore more info,

http://docs.hp.com/cgi-bin/fsearch/framedisplay?top=/hpux/onlinedocs/B2355-90147/B2355-90147_top.html&con=/hpux/onlinedocs/B2355-90147/00/00/15-con.html&toc=/hpux/onlinedocs/B2355-90147/00/00/15-toc.html&searchterms=anonymous%20ftp&queryid=20011106-080927

http://us-support.external.hp.com/cki/bin/doc.pl/sid=b19ae26200e069bb72/screen=ckiSearchResults?mode=id&searchString=HONCIKKBRC00000168

Hope this helps.

Regds

[AriesFR]

Hi,

Anonymous ftp login is made to allow users that have no login/password on your system to be able to remote login via ftp on your system. If this user has any write access on your disk, basically anybody can upload/download what they want there. Your disk is probably full of Warez stuff from nice people...

Disabling that ftp account will only prevent anybody logging in with "ftp" or "anonymous" as their login (any password will usually be ok in that case). If I were you, i'd check for any hidden directory in that write area...

Jean-Charles

[G. Vrijhoeven]

Hi Kathleen,

The big idea is that you enable people to put or get files from your server without creating an account for them.

To prevent it from getting full you can create a monitoring script for the dir you enable people to put files in.

hope this will help

Gideon

[Darrell Allen]

Unless there is a business reason for it, I'd remove the anonymous FTP account. As a general rule services should be disabled unless required. For normal UNIX purposes, you don't need anonymous FTP.

Darrell

[Roger Baptiste]

hi,

Anonymous ftp is just as the name implies -> anybody within the network can ftp to the system anonymously without password restrictions.

Why do we need it? Because it can be useful for allowing users to "put" or "get" files
in a common ftp area (pub/dist) without needing an
account on the system.
For instance, we can use anonymous ftp area to store
some commonly used application tar balls or documents, which can then be
picked up by users in the site
at any time .

All said, anonymous ftp
have to be on systems only
when there is a necessity for it.

-raj

[Kathleen]

How do I check for hidden directories/files?

[AriesFR]

hidden directory/files begin with a dot (.). You can get them with a ls -a for instance or ls -d .* to get only them.

Jean-Charles

[Kathleen]

How do I delete a folder with no name. I see a few out there when I do a ll -a or ls -a but at least 1 has no name.

[AriesFR]

It's name is based on space characters. You can do a rm -ri *
That will remove everything but ask for confirmation. You can then save what you want to keep.

Jean-Charles

P.S.: Thanks to quote answers...

[Craig Rants]

Are you talking about . and .. ? I assume that you are talking about those, you don't want to remove them.

.. is the directory above your current working directory
. is the directory that you are currently in

If you are not talking about those disregard my comments.

C

[Darrell Allen]

Be sure you don't "rm -r ."
or "rm -r .."
or "rm -r .*"
because
. = current directory
.. = parent directory
.* would include both the current and parent directories as well as hidden files / directories

Hidden files / directories start with a . but have more characters in their name.

Darrell

[AriesFR]

No!!! . and .. are NOT to be removed, but hackers usually use names like ' ' (space char) or special chars that can not be displayed. It is then harder to remove them.

By the way, it's rm -ri .*
I forgot the . in my previous message.

Jean-Charles

[Kathleen]

I have one that looks like it has a space in it....do I just do the suggestion above?

[Volker Borowski]

Hello,

there are several ways to safely delete files with special characters.

My favorite is to go with "ftp localhost", because you can type the filename exactly as it shows up and do not have to fear and wildcard-expansion-junk.

Other options are to go by "find". Search the forum on this (find, delete).

Do NOT use "rm" if the filename in charge contains a wildcard or a valid option to the rm-command. I.E. if your file reads like

"-rf * delete_me_please"

...there will not be a second chance if you mistype your quotes.

Be carefull
Volker

[Kathleen]

I got it! Thanks SO much for all of the help.

[Darrell Allen]

Now that I'm back from lunch I can continue my thought.

You can see where rm -r . would be dangerous, especially if done as root, and especially if done in the root directory.

Filenames (hidden or otherwise) can contain characters that aren't visible. Hackers sometimes will ftp in a file with a name that looks like . or .. but really contains unprintable characters. They could potentially create a directory that would be hard to catch simply by doing mkdir ". " or mkdir ".. " (notice the extra space). To see some of the difficulties you would have finding those, make a temp directory somewhere and try the above mkdir's. Then try ll. You can see why (especially if there's a lot of other files in the directory) this is difficult.

Darrell

[Darrell Allen]

Hi Kathleen,

Would you do us a favor? Please assign points to replies to your posts. It's not so much the accumulation of points and hats that drive us (okay, it does to a degree) but the forums become much more valuable if points are applied. When searching the forums for previous threads pertaining to our current issues it is very helpful to see which reply was the right one. And to me, it does mean more to see a answer from someone with a crown. So please take a little time to rate answers. Each one is worth at least some "thank you for trying" points and some truly are the magic answers that will help others down the road.

And I hate to mention this but some people will stop replying to your posts simply because you aren't assigning points.

Darrell

[Darrell Allen]

Hi Kathleen,

I sorry that either my replies didn't help you, I offended you, or both. Based on your assignment of points, I presume it was the second. At the time I believe this thread had no points assigned to replies. I also noticed in your profile you had only assigned points to roughly a fourth of replies to your questions. I wasn't meaning to offend but to remind you of the importance of the point system. To that extent, thank you for the assignments.

Darrell