These notes are from 2012, and probably won't work.
SSH or SFTP into your phone with a regular client.
This requires that you have a rooted phone, and you have Android Ports installed.
dropbear is built to only allow public-key authentication. It is also configured to consider /data/root as root's home directory. The package should have created a /data/root directory for you already. Next step is to generate a key with your ssh client (not covered in this tutorial), and then put that key in the list of authorized keys.
Start a root shell on your phone (adb shell or terminal + su)
Notes: bold = typed
/ # busybox mkdir /data/root / # busybox chmod 700 /data/root / # cd /data/root /data/root # busybox mkdir .ssh /data/root # busybox chmod 700 .ssh /data/root # cat <<EOF >.ssh/authorized_keys > ssh-rsa [your_ssh_key] [your_ssh_key_id] > EOF /data/root # busybox chmod 600 .ssh/authorized_keys /data/root # /data/local/bin/dropbear
From another machine with the ssh key:
$ ssh root@[phone_ip] /data/root #
If dropbear refuses the public key (openssh says: "Permission denied (publickey)."), double-check your permissions on /data/root, /data/root/.ssh, and /data/root/.ssh/authorized_keys. Also double-check that your /data/root/.ssh/authorized_keys contains the correct key and it didn't linewrap
If dropbear accepts the authentication and drops the connection, check to see if you have a /system/xbin/ash. If you don't, create it as a symlink to your shell.
If this does not work, you can kill dropbear and start it with the -F flag. This will print logs to your terminal.