NAT Gateway by iptables dnsmasq
The following guide can be followed on the palm to make a NAT gateway from a usb0 (tether) to ppp0 (EVDO). It is also possible this can be adapted to use a palm pre as a usb wireless adapter, that is NAT gateway from usb0 to eth0. Since wpa_supplicant and wireless tools are included with webos it is also possible that these could be adapted to build your own wifi hotspot from built in commands.
https://help.ubuntu.com/community/Internet/ConnectionSharing
Shut of the Wifi connection on palm
You will need to shut off wifi on your phone (it won't work otherwise). To do this tap on the upper left hand corner where the wifi icon is. Select "Wi-Fi" -> Turn off Wi-Fi
Turn on USBnet on palm
get a root terminal and enter the commands: This requires a reboot so exit anything you're doing on your phone.
usbnet enable reboot
Make dhcp/dns availalbe to usb0 (only do once)
get root terminal and use the following to make dhcp/dns available to usb0
mount -o remount,rw / echo interface=usb0 >> /etc/dnsmasq.palm.conf echo dhcp-range=192.168.2.2,192.168.2.3,2h >> /etc/dnsmasq.palm.conf stop dnsmasq start dnsmasq mount -o remount,ro /
Setup packet forwarding
ifconfig usb0 up ifconfig usb0 192.168.2.1 sysctl -w net.ipv4.conf.default.forwarding=1 sysctl -w net.ipv4.conf.all.forwarding=1 iptables -t nat -A POSTROUTING -o ppp0 -s 192.168.2.0/24 -j MASQUERADE iptables -t nat -A PREROUTING -i ppp0 -p tcp --dport 3074 -j DNAT --to-destination 192.168.2.2 iptables -t nat -A PREROUTING -i ppp0 -p udp -m multiport --dports 88,3074 -j DNAT --to-destination 192.168.2.2 iptables -A FORWARD -i ppp0 -d 192.168.2.2 -p tcp --dport 3074 -j ACCEPT iptables -A FORWARD -i ppp0 -d 192.168.2.2 -p udp -m multiport --dports 88,3074 -j ACCEPT
Setup your computer
On Ubuntu Linux 10.04 in network manager right click the icon select "Edit Connections". Find the wired interface probably named "Auto usb" edit and uncheck "connect automatically" box.
Windows / Mac instructions coming soon.
Trouble Shooting
Make sure both these values are 1.
sysctl net.ipv4.conf.default.forwarding net.ipv4.conf.all.forwarding
Beware, the palms seems to like setting this to 0 whenever network settings are changed.