The best way to do this is to create a chroot jail for the user. I'll clean up the answer here when I get home but I posted the solution on my blog.
https://thefragens.com/chrootd-sftp-on-mac-os-x-server/
Below are most of the instruction from the above post.
First, you should create the new user in Workgroup Admin and either assign them access privileges for SSH via Server Admin or assign them to a group that has SSH access privileges. Further discussion is below.
From the Terminal, start off right.
sudo cp /etc/sshd_config /etc/sshd_config.bkup
sudo chown root /
sudo chmod 755 /
sudo mkdir -p /chroot/user/scratchpad
sudo chown -R root /chroot
sudo chown user /chroot/user/scratchpad
sudo chmod -R 755 /chroot
Every additional new user added will then be something along the lines of the following.
sudo mkdir -p /chroot/user2/scratchpad
sudo chown root /chroot/user2
sudo chown user2 /chroot/user2/scratchpad
sudo chmod -R 755 /chroot/user2
Every folder it the path to the chroot jail must be owned by root
. I don't think it matters what group the folder is in. What I did above was to
- backup
/etc/sshd_config
- change ownership of the root directory to
root
- change permissions of the root directory to 755
- create a chroot folder
- create a user folder inside the chroot folder
- create a folder inside the user folder that user can modify
- set ownership and permissions
Now to edit /etc/sshd_config
to the following.
#Subsystem sftp /usr/libexec/sftp-server
Subsystem sftp internal-sftp
Match User user
X11Forwarding no
AllowTcpForwarding no
ForceCommand internal-sftp
ChrootDirectory /chroot/user
This creates a chroot jail that when the user logs in will drop them into the folder /chroot/user
, in that folder is a folder they can add things to /chroot/user/scratchpad
.
If you want to create a Group in Workgroup Admin for 'Chroot Users' then add the new users that you created in Workgroup Admin to the Group you won't have to keep editing the /etc/sshd_config
file. Instead of the above, add the following. Make sure you add the 'Chroot Users' group to the SSH access ACL in Server Admin.
Match Group chrootusers
X11Forwarding no
AllowTcpForwarding no
ForceCommand internal-sftp
ChrootDirectory /chroot/%u
To test whether the above is working, issue the following from the terminal.
$ sftp user@domain.com
Password:
sftp>
If you've simply created a DSA key as root, it would be safest to do the following (from a terminal as your own user):
mkdir -p ~/.ssh
sudo cp -av /var/root/.ssh/id_dsa /var/root/.ssh/id_dsa.pub /Users/$USER/.ssh/
chown -v $USER: ~/.ssh/id_dsa*
chmod -v 600 ~/.ssh/id_dsa
This will create a .ssh
configuration directory in your homedir (mkdir -p
won't make loud noises if ~.ssh
already exists, and won't do anything), copy the public and private key files from root
's homedir to your own, then set the correct permissions and ownership on your files.
This is non-destructive (you're not moving anything, you're just copying); once you're happy the key-pair is letting you connect to your remote host successfully as your normal login user, you can sudo rm -fv /var/root/.ssh/id_dsa /var/root/.ssh/id_dsa.pub
This also doesn't affect any other files in either account's .ssh
folder.
Best Answer
In the find file window, press Command-Shift-G. It'll ask you what folder to navigate to. Enter
~/.ssh
and press return.