How can I chroot sftp-only SSH users into their homes?

I want to give a client access to my server, but I want to limit those users to their home directories. I will bind-mount in any files I want them to be able to see. I've created a user called bob and added him to a new group called sftponly. They have a home directory at /home/bob. I've changed their shell to /bin/false to stop SSH logins. Here is their /etc/passwd line: bob:x:1001:1002::/home/bob:/bin/false I've also changed the /etc/ssh/sshd_config to include the following: Match Group sftponly         ChrootDirectory /home/%u         ForceCommand internal-sftp         AllowTcpForwarding no When I try to log in as them, here's what I see $ sftp bob@server bob@server's password:  Write failed: Broken pipe Couldn't read packet: Connection reset by peer If I comment out the ChrootDirectory line I can SFTP in but then they have free rein over the server. I have found that ChrootDirectory /home works, but it still gives them access to any home directory. I have explicitly tried ChrootDirectory /home/bob but that doesn't work either. What am I doing wrong? How can I limit bob to /home/bob/? ----EDIT----- Okay so I just had a look at /var/log/auth.log and saw this: May  9 14:45:48 nj sshd[5074]: pam_unix(sshd:session): session opened for user bob by (uid=0) May  9 14:45:48 nj sshd[5091]: fatal: bad ownership or modes for chroot directory component "/home/bob/" May  9 14:45:48 nj sshd[5074]: pam_unix(sshd:session): session closed for user bob I'm not entirely sure what's going on there,  but it suggests something is wrong with the user directory. Here is the ls -h /home output: drwxr-xr-x 26 oli      oli      4096 2012-01-19 17:19 oli drwxr-xr-x  3 bob      bob      4096 2012-05-09 14:11 bob     ssh chroot sftp     shareimprove this question edited Mar 12 '14 at 19:03         rm-vanda        492518     asked May 9 '12 at 13:43         Oli        138k29347549

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All this pain is thanks to several security issues as detailed here. Basically the chroot directory has to be owned by root and can't be any group-write access. Lovely. So you essentially need to turn your chroot into a holding cell and within that you can have your editable content. sudo chown root /home/bob sudo chmod go-w /home/bob sudo mkdir /home/bob/writeable sudo chown bob:sftponly /home/bob/writeable sudo chmod ug+rwX /home/bob/writeable And bam, you can log in and write in /writeable. shareimprove this answer edited Sep 26 '12 at 6:35                 answered May 9 '12 at 14:21         Oli        138k29347549

2                         Thank you really useful. Two problems though. 1.) Even though I can't write, I can still browse the whole filesystem. 2.) Changing shell to /bin/false prevents SFTP completely. Am I doing something wrong?                �C                     kim3er                Jun 7 '12 at 15:30                                                                             Thank you!  Many other articles on this topic miss this detail, and some make it so the server cannot accept ssh connections (which kind of sucks when you're on EC2 and ... that's the only way).                �C                     Tom Harrison Jr                Sep 25 '12 at 22:56                                                                             @kim3er did you set your user's group to sftponly? If you don't, the ssh server won't match and chroot it. Try "usermod sftponly $USER". Also, /bin/false just removes SSH access. If you want a chrooted user to have ssh access there are more steps you'll need to take.                �C                     Evan Plaice                Apr 26 '13 at 17:47                                                                             3                         kim3er: this is because you need to set the user's shell to /sbin/nologin -- /bin/false disables any sort of access.                �C             user162889                May 29 '13 at 21:09                                                                             4                         I'd also like to note that all folders that lead to your chroot folder should be owned by root. In this example, /home should also be owned by root.                �C                     Shiki                Oct 8 '13 at 10:18                                                                             show 1 more comment

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To chroot an SFTP directory, you must 1) create an user and force root to be owner of it cd /home mkdir john useradd -d /home/john -M -N -g users john sudo chown root:root /home/john sudo chmod 755 /home/john 2) Change the subsystem location on /etc/ssh/sshd_config: #Subsystem sftp /usr/lib/openssh/sftp-server Subsystem sftp internal-sftp and create a user section at the end of the file (ssh can die respawning if placed after Subsystem line): Match User john     ChrootDirectory /home/john     ForceCommand internal-sftp     AllowTCPForwarding no     X11Forwarding no     shareimprove this answer edited Dec 15 '14 at 16:59         mniess        4,48611443     answered Oct 25 '12 at 17:54         josircg        5561611

Thank you so much!                �C                     Sobiaholic                Sep 2 '13 at 21:13                                                                             add a comment

                       

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I spent the whole day trying to get a network share on my raspberry. I wanted to lock the user so that it would not be able to navigate through the whole file system, no ssh login access and I wanted to have write access to the network share. And here is how I got it working: First I created a user: sudo useradd netdrive Then edited /etc/passwd and made sure it has /bin/false for the user so the line was: netdrive:x:1001:1004:Net Drive User,,,:/home/netdrive:/bin/false I edited /etc/ssh/sshd_config to include: Match User netdrive   ChrootDirectory /home/netdrive   ForceCommand internal-sftp   AllowTcpForwarding no   X11Forwarding no Changed home directory owner and permissions: sudo chown root:root /home/netdrive/ sudo chmod 755 /home/netdrive/ Ok so after all this I was able to connect using sshfs but in read only mode. What I had to do to get a writable folder: sudo mkdir -p /home/netdrive/home/netdrive/ sudo chown netdrive:netdrive /home/netdrive/home/netdrive/ sudo chmod 755 /home/netdrive/home/netdrive/ That was it, it worked without any further changes. Note that I have only writable permissions to the user, not to the group as many other solutions online. I was able to create/delete/edit/rename files/folders without problems. When accessing using sshfs with the netdrive user because of chroot configuration I would only see things stored inside server's /home/netdrive/ directory, perfect. The repeated /home/netdrive/home/netdrive/ directory structure is what made it work for me in having a clean chroot ssh writable solution. Now I am going to explain below the problems I had: You should probably not execute the following paragraphs: After looking at the above solutions (and many others on the net which even used acl (access control lists)) I was still not able to get it working because what I did next was: The following did NOT work for me: sudo mkdir /home/netdrive/writable/ sudo chown netdrive:netdrive /home/netdrive/writable/ sudo chmod 755 /home/netdrive/writable/ Because the netdrive user was still not able to write in that /home/netdrive/writable/ directory despite owning the folder and having the permissions. Then I did:    sudo chmod 775 /home/netdrive/writable/ And now I could create a directory and delete it but I was not able to edit it because it was being created without group writable permissions. Here from what I saw on the net people use acl to fix it. But I was not happy with that since it I had to install acl, then configure mount points, etc. Also I have no idea why I would need group permission to write to a folder owned by the same user. It seems that for some reason creating /home/netdrive/home/netdrive and giving ownership to the last netdrive folder I was able to make everything work without messing with group permissions. shareimprove this answer