Ubuntu – How to setup virtual users for vsftpd with access to a specific sub directory

ftppermissionsservervsftpd

I need to be able to add a virtual users to vsftpd that only have access to a sub folder. The reason why I want to use virtual users is I only want to have 1 real user on the server.

The FTP structure is:

  • www
    • website_name1
      • sub_folder1
    • website_name2
      • sub_folder2
      • sub_folder3
    • website_name3
    • website_name4

The main account has access to the www folder and all sub directories and I want to add a virtual user that can have access to the sub_folder1 and only sub_folder1

Also to avoid some confusion I would also require another user to access sub_folder3 and only sub_folder3. My point being I need to be able to choose which folder and sub folders on a user by user basis.

I have found ways to to add users to see the whole strucutre or setup user named folders both of which have no use to me.

I found a similar question posted here:

How to setup VSFTPD for multiple users including adding specific directories

but it recommends proftpd which I though was general less secure.
Or have I missed the point here?

Best Answer

  • With a bit of playing around I've managed to come up with a semi solution (not perfect but good enough)

    using 2707974 answer and information I've gained else where I've been able to get what I need.

    First you need vsftp and PAM installed

    apt-get install vsftpd libpam-pwdfile
    

    Edit /etc/vsftpd.conf

    nano /etc/vsftpd.conf
    

    then paste in the following

    listen=YES
    anonymous_enable=NO
    local_enable=YES
    write_enable=YES
    local_umask=022
    local_root=/var/www
    chroot_local_user=YES
    allow_writeable_chroot=YES
    hide_ids=YES
    
    #virutal user settings
    user_config_dir=/etc/vsftpd_user_conf
    guest_enable=YES
    virtual_use_local_privs=YES
    pam_service_name=vsftpd
    nopriv_user=vsftpd
    guest_username=vsftpd
    

    Edit to your exact needs the most important bit for virtual users is everything after the virtual user settings comment

    Creating User

    You can either use a database or htpasswd I found htpasswd faster and easier to use.

    make a directory to store your users

    mkdir /etc/vsftpd
    htpasswd -cd /etc/vsftpd/ftpd.passwd user1
    

    adding additional users just omit the -c

    htpasswd -d /etc/vsftpd/ftpd.passwd user2
    

    I've only managed to get it to work using CRYPT which limits to 8 chars to use more than 8 chars use openssl to generate a compatible hash and pipe directly into htpasswd

    htpasswd -c -p -b /etc/vsftpd/ftpd.passwd user1 $(openssl passwd -1 -noverify password)
    

    Once your users are created you can now change your PAM config file

    nano /etc/pam.d/vsftpd
    

    and remove everything inside this file and replace with the following

    auth required pam_pwdfile.so pwdfile /etc/vsftpd/ftpd.passwd
    account required pam_permit.so
    

    This will enable login for your virtual users defined in /etc/vsftpd/ftpd.passwd and will disable local users

    Next we need to add a user for these virtual users to use. These users will not have access to the shell and will be called vsftpd

    useradd --home /home/vsftpd --gid nogroup -m --shell /bin/false vsftpd
    

    the user must match guest_username=vsftpd in the vsftpd conf file

    Defining Directory Access

    The important line here is the following

    user_config_dir=/etc/vsftpd_user_conf
    

    this means that when user1 logs in it will look for the following file

    /etc/vsftpd_user_conf/user1
    

    this file the same as the vsftpd.conf so you can define a new local_root

    going back to the question we want user1 to only have access to var/www/website_name1/sub_folder1, so we need to create the vsftpd_user_conf folder:

    mkdir /etc/vsftpd_user_conf
    

    Now create the user file:

    nano /etc/vsftpd_user_conf/user1
    

    and enter the following line

    local_root=/var/www/website_name1/sub_folder1
    

    Now restart vsftp

    service vsftpd restart
    

    you should now be able to login as user1 who will only be able to see var/www/website_name1/sub_folder1 and any folder and file inside it.

    That's it you can now add as many users as you want and limit their access to whatever folder you wish.

    important to remember if you do not create a user conf file it will default to the var/www folder as root (in the example above)

    If the subfolder is intended to be modifiable by the user, it might be necesary to change the owner of the shared subfolder:

    chown vsftpd:nogroup /var/www/website_name1/sub_folder1