It's almost as if it's ignoring the authorized_keys file. I've verified that the nvram has my key in it, and that the same key is copied to /tmp/home/root/.ssh/authorized_keys on the Tomato router. I can use the same key to connect to a normal Linux server running OpenSSH.
I've tried looking at the logs, and even running the dropbear daemon from the command line, but I'm not getting any useful error messages. I've tried modifying the permissions of everything in the /tmp/home/root/.ssh/authorized_keys tree to 600 or 700.
I'm running TomatoUSB 1.28 on a Linksys E3000.
Tomato Firmware v1.28.9054 MIPSR2-beta E3000 USB vpn3.6
root@home:/tmp/home/root/.ssh# ls -lad /tmp
drwxrwxrwx 7 root root 140 Dec 31 1969 /tmp
root@home:/tmp/home/root/.ssh# ls -lad /tmp/home/
drwxr-xr-x 3 root root 60 Dec 31 1969 /tmp/home/
root@home:/tmp/home/root/.ssh# ls -lad /tmp/home/root/
drwx-- 3 root root 60 Mar 27 00:08 /tmp/home/root/
root@home:/tmp/home/root/.ssh# ls -lad /tmp/home/root/.ssh/
drwx-- 2 root root 60 Mar 27 00:08 /tmp/home/root/.ssh/
root@home:/tmp/home/root/.ssh# ls -lad /tmp/home/root/.ssh/authorized_keys
-rwx-- 1 root root 1013 Mar 27 21:36 /tmp/home/root/.ssh/authorized_keys
root@home:/tmp/home/root/.ssh# grep root /etc/passwd
root@home:/tmp/home/root/.ssh# ls -lad /root
lrwxrwxrwx 1 root root 13 Nov 30 2010 /root -> tmp/home/root
Anyone have any ideas? Anyone know how to possibly gdb dropbear remotely, or drop a version in that prints better error messages? Is there a doc that describes how to setup a toolchain to compile Tomato from scratch?