Since we have telnet access, and all our apps run excellently, there is no need to do firmware inspection. Sorry.
It's not like I have time to spare :)
Here's some pointers of how to get a toolchain and shell working. The info below is compiled from various posts over at the netoworkedmediatank.com forum:
A toolchain is available at CoudeSourcery.com. Look for "CodeSourcery G++ Lite for MIPS".
The C200 reports:
# uname -a Linux PCH-C200 22.214.171.124-19-sigma #330 PREEMPT Fri Sep 4 10:21:37 MYT 2009 mips unknown
sigma designs tangoX MIPS 74K V4.9 FPU V0.0.
The configure needs Little Endian:
./configure --host=mips-linux-gnu CFLAGS=-EL CXXFLAGS=-EL LDFLAGS=-EL CPPFLAGS=-EL ASFLAGS=-EL CC="mips-linux-gnu-gcc -EL"
With the CodeSourcery toolchain you can probably also use
which should be the right target. This should encourage gcc to order the assembly for best performance on the C200. Not sure what the trailing c represents though.
As the PTY is disabled currently, we will not have "real" telnet. But you can get lundman's shell here: http://www.lundman.net/ftp/nmt/shell.zip
Unzip and rename the shell-installer.cgi-RENAME-ME file to shell-installer.cgi as WinZip corrupts it.
Upload to root of HDD, make it executable, then run it like any cgi. You can use my hacked html/cgi files too if you want, I have not had time to make it nice though..
It will "hang" after spawning shell, but that's ok, just let it be or push STOP then SOURCE button to return to normal GUI.
Connect to port 2222 on C200. Please note you can not use "telnet" as it insist on sending cr/nl, unless you find the option to disable that in telnet, or change shell.c to send DONT CRNL in telnet speak.
Use netcat to connect:
nc ip.ip.ip.ip 2222
Then type in sh or /bin/sh as the process to run, and you are set. You can connect as many times as you want.
upnp crashes, so compile strace to find out why.
cd /tmp wget http://lundman.net/ftp/nmt/strace.c200 chmod 755 strace.c200 killall upnpapp cd /opt/syb/app/upnp /tmp/strace.c200 -fv -a 200 -s 200 /opt/syb/app/upnp/upnpapp &