Connecting from Linux to WinCE 2.11

Submitted by Arthur Tyde and Bryan Abshier of Linuxcare Inc.

This will tell you how to set up a masqueraded PPP connection via. IrDA from WinCE to a Linux based notebook computer. Once you are IP connected, the rest is up to you. We put this together as a guide for Sony notebook users with Casio E-100/105 PDA's, though the procedure should work for any WinCE 2.11 device with infrared capabilities talking to any notebook. Do all the Linux side testing signed on as root, standard warnings apply.

Configure WinCE Configure a network connection for your WinCE device. Go into "Connections" and create a "Direct Connection" Name it something meaningful, for device select "Infrared Port". Go into settings and change the baud rate to 115200, this is the max for WinCE. Go to TCP/IP settings and check "Use server-assigned IP address," and "Use software compression," and "Use IP header compression" Make sure "Use Slip," is unchecked. For Name Servers, make sure "Use server-assigned addresses" is checked. Go to Start, Settings, Communications, Identification and enter something for the Device Name. (I used "cetoy") You most likely already have these values set if you have synced with a Win9x desktop using Activesynch.

Configure Linux/IrDA Set up IrDA support on your notebook (described elsewhere) and get to the point where your notebook will discover an IrDA compliant device. A good sign is the irda0 device will show up when you execute ifconfig. It will not have an IP address, this is ok.

Setup the Connection Test the discovery by setting an IrDA device in range of your IR port, wait 5 seconds, and;

cat /proc/net/irda/discovery

For example, the Ericsson I888 World Phone with IR port enabled should immediately show something like this;

"name:I 888 WORLD   ,hint:0x9104,saddr:0x838470e5,daddr:0x152dceaa"

Your WinCE machine will not be discovered unless it's actively looking for a connection. So, if you want to test with WinCE position your device and double tap on the network icon you created in step 2, you should see something like this:

"name:mytoy,hint:0x8204,saddr:0x838470e5,daddr:0x00000b72"

The name displayed will be whatever value you have entered into the Start, Settings, Communications, Identification as the Device Name. At this point, with basic IrDA functioning- we can move on to establishing a PPP connection for WinCE. These scripts can also be used for serial cable connects. Create the following files and copy them into the directory indicated.

/usr/sbin/cebox.sh - make it executable

#!/bin/sh
pppd call cebox

Because Microsoft likes to break standards, you need the following chat script. This will feed WinCE the proper ASCII keywords it wants before allowing a PPP connection.

/etc/ppp/cebox.chat

TIMEOUT 3600
"CLIENT"    "CLIENT\c"
""      "SERVER\c"

The following file will allow you to specify the IP addresses, IR (or serial port if using a cable) device, DNS and so forth. I do not recommend you change the 192.IP addresses below. WinCE really has an affection for 192.168.55.100 because all the MS synch tools seem to have it hardcoded. DNS can be whatever you normally use.

/etc/ppp/peers/cebox

/dev/ircomm0 115200 crtscts
connect '/usr/sbin/chat -v -f /etc/ppp/cebox.chat'
noauth
local
192.168.55.101:192.168.55.100
ms-dns 10.2.0.1

Testing the connection Ok, now you can test the connection to make sure it all works. Reboot your machine, run irattach /dev/ttyS2 -s (/dev/ttyS2 being the serial port your BIOS sees the IR device as, if irattach is not running, start it) Align the IR ports, at the Linux command prompt type /usr/sbin/cebox.sh, and simultaneously press return to start cebox and double tap your connection icon in WinCE. You should get a happy message from WinCE reporting Connecting to Host, Device Connected, Authenticating User, User Authenticated and finally Connected. You should see something like this when you are connected:

irda0     Link encap:IrLAP  HWaddr 06:89:d0:58
      UP RUNNING NOARP  MTU:2048  Metric:1
      RX packets:246 errors:0 dropped:0 overruns:0 frame:0
      TX packets:251 errors:0 dropped:0 overruns:0 carrier:0
      collisions:0 txqueuelen:8

ppp0      Link encap:Point-to-Point Protocol
      inet addr:192.168.55.101 P-t-P:192.168.55.100 Mask:255.255.255.255
      UP POINTOPOINT RUNNING NOARP MULTICAST  MTU:1500  Metric:1
      RX packets:10 errors:0 dropped:0 overruns:0 frame:0
      TX packets:10 errors:0 dropped:0 overruns:0 carrier:0
      collisions:0 txqueuelen:10

The following script sets up IrDA, establishes a ppp connection with WinCE, and then sets up IP masquerading. It is provided as an example of how you can tie this all together. This is more or less a manual approach. You can get creative, start irattach at boot and stick a line in inittab to constantly look for a WinCE connection on the IR port. This will however, run down your batteries and limit your ability to access other IR gadgets. I just use the script below. Position the device, run wince and start communications on your PDA when the script tells you to.

/usr/local/bin/wince - make this executable

#!/usr/bin/perl
use strict;
#
# Enable IrDA, start ppp0 and set up WinCE masquerading
# A. Tyde - Linuxcare Inc.
#
print "\n-> Setting up IR infrastructure...\n";
system("killall irattach 2>/dev/null");
sleep 1;
system("/usr/sbin/cebox.sh");
print "   Start WinCE Serial or IR networking now!\n";
open(ECHO,">/proc/sys/net/ipv4/ip_forward") or die "Can not open /proc/sys/net/
ipv4/ip_forward";
print ECHO "1";
close (ECHO);
print "   Serving 192.168.55.100 to WinCE device...\n\n";
system("ipchains -F");
sleep 5;
system("ipchains -P forward DENY");
system("ipchains -A forward -s 192.168.55.100/32 -j MASQ");
exit 0;