as far as i know both ftp and sftp allow a user to move about using regular permissions.

So basicalkly, you solution will be to setup very restrictive group permissions on your directories. John has more experience with the kind of policy that you need to define and setup.

What you will to focus on is the meaning of the permission bits for directory.

R means you can read the directory: sort of like looking thru a glassdoor with the loght on. You can see the objects.

W means you put new objects (files/directories) in the directory, and remove those you know the exact name of (assuming you have no R access).

X means access: in particular --x this means you can access the directory (or open the door) but there is no light. If you know the name of an object you can access it if the object permission bits allow it (i.e. --x gives you access to objects you know or can guess, you cannot list all objects). The X bit is also known as the SEARCH bit, as it permits the SEARCH of directories included in a PATH variable for a program to execute. Again, whether a program can actually be executed depends on it's permissions, not those of the directory.

It can be quite confusing initially. I suggest you make some directories and files and change the permissions.

Lastly: if you are the OWNER, only the owner bits are valid.
If you are not the owner, but are a GROUP member, only the group bits are valid
Otherwise the OTHER bits are valid.

Initially, try to not depend on the use of ACL's - unless this is for a single user only. ACL's are very complex to manage.

Google Translation....

Very Good, because vereis I have a problem with SFTP and to see if they can help me… is the following thing: I have a servant to whom it is possible to be acceded by means of SFTP, the problem is that the user can see all the disc of the servant when this inside. As it could avoid this. With FTP this does not happen because the single user sees his directory outside home as if the root of the machine. Sure FTP then encripta password and is not worth to me. I have proven with chroot and I have not obtained that it works. Greetings and Thanks beforehand.

So What I am understanding here is that you are having a problem with the differences between FTP anonoymous accounts (which have a chroot performed automatically) and sftp which logs the user in a regular user.

So before continuing, I would like to be sure that I have understood your question, and if so, when using ftp (e.g. filezilla) does the user see only his own files, or can he/she access the regular root.

Are you using FTP from UNIX, AIX, Windows, Linux, or something else? same for SFTP.

regards,
Michael