USB Networking

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Revision as of 17:18, 28 August 2007 by Tyrael (Talk | contribs)

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Contents

Neo1973 side

By default Neo1973 has usb0 interface working due to Ethernet gadget (g_ether) compiled into kernel.

On the Neo, if you want to reach out to the internets using full qualified hostnames, you need to define your DNS server. Create a file /etc/resolv.conf with at least one line saying

nameserver xxx.xxx.xxx.xxx

e.g. nameserver 192.168.1.1

Then you can also easily update your 2007.2 OpenMoko packages with "ipkg update && ipkg upgrade" on the Neo.

Desktop side

Manual method

With the device connected, modprobe usbnet module and configure usb0 interface (as root):

ifconfig usb0 192.168.0.200 netmask 255.255.255.0

If your eth0 interface is also in the same 'range' (e.g. 192.168.0.105) then you can do the following:

1. ping the Neo with

# ping -I usb0 192.168.0.202

2. add a route to your Neo:

# /sbin/route add -host 192.168.0.202/32 dev usb0

3 log in to the Neo

# ssh root@192.168.0.202

If you don't have the necessary modules to get usb0 going, make sure you have the following kernel options enabled:

  • CONFIG_USB_USBNET
  • CONFIG_USB_NET_CDCETHER

Both options are available in the Device Drivers -> USB support -> USB Network Adapters. For more info see the usbnet driver homepage.

Automatic method

Took from Hotplugging usbnet post by Marcin 'Hrw' Juszkiewicz.

For Debian or similar distros: Edit /etc/network/interfaces file ():

allow-hotplug usb0
iface usb0 inet static
        address 192.168.0.200
        netmask 255.255.255.0
        network 192.168.0.0
        post-up iptables -A POSTROUTING -t nat -j MASQUERADE -s 192.168.0.0/24
        post-up echo 1 > /proc/sys/net/ipv4/ip_forward
        post-up iptables -P FORWARD ACCEPT

For Ubuntu Feisty "allow-hotplug" doesn't work. Use:

auto usb0

If you are doing the echo 1 > /proc/... command manually, sudo may not be enough, then you will have to execute it from a sudo bash.

Ubuntu feisty appears to have a bug where ifdown is not run when the interface is unplugged, meaning this only works once after the system is booted. One can patch /etc/udev/rules.d/85-ifupdown.rules, adding a last line:

SUBSYSTEM=="net", ACTION=="remove",             RUN+="/sbin/start-stop-daemon --start --background --pidfile /var/run/network/bogus --startas /sbin/ifdown -- --allow auto $env{INTERFACE}"

and remove the similar remove like earlier.

For Red Hat or similar distros Edit /etc/sysconfig/network-scripts/net.hotplug:

After this statement:

    case $INTERFACE in
	# interfaces that are registered after being "up" (?)

Add the following:

	usb0)
		ifconfig usb0 192.168.0.200 netmask 255.255.255.0
		route add 192.168.0.202 usb0
		iptables -I INPUT 1 -s 192.168.0.202 -j ACCEPT
		iptables -I OUTPUT 1 -s 192.168.0.200 -j ACCEPT
		exit 0
	;;

For Gentoo or similar distros:

  • Edit /etc/conf.d/net by adding:
   # Neo1973
   config_usb0=( "192.168.0.200 netmask 255.255.255.0" )
  • Create a new init script:
   # cd /etc/init.d
   # ln -s net.lo net.usb0

And now when you connect phone (which has 192.168.0.202 IP) it gets connection to world automatically.

For MacOS X:

there are no files to edit since hotplugging configuration is done automatically by default. Of course, the interface has been initialized once. Install the AJZaurusUSB driver as described on MacOS_X and then open System Preferences / Networks which will show the new interface. Configure for Manual DHC with Host address 192.168.0.200 and Gateway 192.168.0.202.

Mobile development

Proxying DNS requests

If, like me, you move about quite a lot, connecting to various networks as you go and getting your ip via dhcp, you'll probably be annoyed at having to constantly update your resolv.conf on the Neo 1973.

To get round this, as part of my setup script, I run a proxy dns on the ip address the neo comes in on at the usb0 port. This means that my Neo /etc/resolv.conf only contains

nameserver 192.168.0.200 

and my laptop will proxy all dns requests based on it's own /etc/resolv.conf

note that we only run the dns proxy on the usb0 interface so that we don't break any other networking

The script is designed to use dnrd as the dns proxy. The script and a copy of dnrd are available from my site. The script also performs the initial setup of the connection as per the USB_Networking#Manual_method above.

Connecting to phone

Then ssh root@192.168.0.202 with empty password to get into phone.

NOTE: the ssh daemon (dropbear 0.49) on the OpenMoko appears to have a bug when sending the exit status back to the client. From time to time you receive an exit status of 255.

SSH Extras

If you get fed up with typing root@192.168.0.202, on your PC edit /etc/hosts and add an entry for 'phone'

192.168.0.202 phone

then edit ~/.ssh/config (or create it) and add

host phone
user root

then all you need to do is type

# ssh phone

You might want to use keys to bypass the login prompt too.

SSH Keys

From host to phone

To generate ssh keys for use as a login mechanism type

ssh-keygen -t rsa

when prompted for a password either hit enter for no password (not really a good idea) or enter a password for this key. ssh into the phone and create ~/.ssh

# mkdir ~/.ssh

then from your PC copy the .pub file to the phone.

# scp ~/.ssh/id_rsa.pub phone:.ssh/authorized_keys

You should now be able to ssh directly into the phone.

To disable password logins (after setting up key access) edit /etc/init.d/dropbear and change the following line:

DROPBEAR_EXTRA_ARGS=

to

DROPBEAR_EXTRA_ARGS="-s"

You will need to restart dropbear for this to take effect.

From phone to host

Generate the key

 dropbearkey -t rsa -f id_rsa

The output will look something like this:

 Will output 1024 bit rsa secret key to 'id_rsa'
 Generating key, this may take a while...
 Public key portion is:
 ssh-rsa AAAAB3Nza[...]
 Fingerprint: md5 ca:e8:f0:b7:f6:7b:c2:b6:b9:71:e4:45:86:a9:ff:b8

Copy and paste the one line (in this example, starting with 'ssh-rsa' onto the end of the host's authorized_keys file (often in ~/.ssh/).

From the phone, ssh with -i:

 ssh -i id_rsa user@host

This works for me. I ripped off these instructions from: [[1]]

GUI on desktop through SSH

If you need to get the GUI on the phone onto the desktop via usb, you can use ssh as follows

 ssh -l root -X -v 192.168.0.202

Login, and run openmoko-finger-demo for example, and it will open up on the desktop. To get landscape view, just resize the GUI window on the desktop.

Remote apps on neo

To get desktop apps to show up on your neo, first log in to the phone

 ssh -l root 192.168.0.202

Then once inside, run:

 DISPLAY=:0 xhost +192.168.0.200

After this you can close the ssh session. Back on the desktop computer, run:

 DISPLAY=moko:0 xclock

Note that the xhost command will allow remote applications on 192.168.0.200 to access the X server. It will allow anyone on the desktop machine to access the X server of the neo, including snooping anything you type on it. To disallow remote applications again, run this in the neo:

 DISPLAY=:0 xhost -192.168.0.200

Personal tools

Neo1973 side

By default Neo1973 has usb0 interface working due to Ethernet gadget (g_ether) compiled into kernel.

On the Neo, if you want to reach out to the internets using full qualified hostnames, you need to define your DNS server. Create a file /etc/resolv.conf with at least one line saying

nameserver xxx.xxx.xxx.xxx

e.g. nameserver 192.168.1.1

Then you can also easily update your 2007.2 OpenMoko packages with "ipkg update && ipkg upgrade" on the Neo.

Desktop side

Manual method

With the device connected, modprobe usbnet module and configure usb0 interface (as root):

ifconfig usb0 192.168.0.200 netmask 255.255.255.0

If your eth0 interface is also in the same 'range' (e.g. 192.168.0.105) then you can do the following:

1. ping the Neo with

# ping -I usb0 192.168.0.202

2. add a route to your Neo:

# /sbin/route add -host 192.168.0.202/32 dev usb0

3 log in to the Neo

# ssh root@192.168.0.202

If you don't have the necessary modules to get usb0 going, make sure you have the following kernel options enabled:

  • CONFIG_USB_USBNET
  • CONFIG_USB_NET_CDCETHER

Both options are available in the Device Drivers -> USB support -> USB Network Adapters. For more info see the usbnet driver homepage.

Automatic method

Took from Hotplugging usbnet post by Marcin 'Hrw' Juszkiewicz.

For Debian or similar distros: Edit /etc/network/interfaces file ():

allow-hotplug usb0
iface usb0 inet static
        address 192.168.0.200
        netmask 255.255.255.0
        network 192.168.0.0
        post-up iptables -A POSTROUTING -t nat -j MASQUERADE -s 192.168.0.0/24
        post-up echo 1 > /proc/sys/net/ipv4/ip_forward
        post-up iptables -P FORWARD ACCEPT

For Ubuntu Feisty "allow-hotplug" doesn't work. Use:

auto usb0

If you are doing the echo 1 > /proc/... command manually, sudo may not be enough, then you will have to execute it from a sudo bash.

Ubuntu feisty appears to have a bug where ifdown is not run when the interface is unplugged, meaning this only works once after the system is booted. One can patch /etc/udev/rules.d/85-ifupdown.rules, adding a last line:

SUBSYSTEM=="net", ACTION=="remove",             RUN+="/sbin/start-stop-daemon --start --background --pidfile /var/run/network/bogus --startas /sbin/ifdown -- --allow auto $env{INTERFACE}"

and remove the similar remove like earlier.

For Red Hat or similar distros Edit /etc/sysconfig/network-scripts/net.hotplug:

After this statement:

    case $INTERFACE in
	# interfaces that are registered after being "up" (?)

Add the following:

	usb0)
		ifconfig usb0 192.168.0.200 netmask 255.255.255.0
		route add 192.168.0.202 usb0
		iptables -I INPUT 1 -s 192.168.0.202 -j ACCEPT
		iptables -I OUTPUT 1 -s 192.168.0.200 -j ACCEPT
		exit 0
	;;

For Gentoo or similar distros:

  • Edit /etc/conf.d/net by adding:
   # Neo1973
   config_usb0=( "192.168.0.200 netmask 255.255.255.0" )
  • Create a new init script:
   # cd /etc/init.d
   # ln -s net.lo net.usb0

And now when you connect phone (which has 192.168.0.202 IP) it gets connection to world automatically.

For MacOS X:

there are no files to edit since hotplugging configuration is done automatically by default. Of course, the interface has been initialized once. Install the AJZaurusUSB driver as described on MacOS_X and then open System Preferences / Networks which will show the new interface. Configure for Manual DHC with Host address 192.168.0.200 and Gateway 192.168.0.202.

Mobile development

Proxying DNS requests

If, like me, you move about quite a lot, connecting to various networks as you go and getting your ip via dhcp, you'll probably be annoyed at having to constantly update your resolv.conf on the Neo 1973.

To get round this, as part of my setup script, I run a proxy dns on the ip address the neo comes in on at the usb0 port. This means that my Neo /etc/resolv.conf only contains

nameserver 192.168.0.200 

and my laptop will proxy all dns requests based on it's own /etc/resolv.conf

note that we only run the dns proxy on the usb0 interface so that we don't break any other networking

The script is designed to use dnrd as the dns proxy. The script and a copy of dnrd are available from my site. The script also performs the initial setup of the connection as per the USB_Networking#Manual_method above.

Connecting to phone

Then ssh root@192.168.0.202 with empty password to get into phone.

NOTE: the ssh daemon (dropbear 0.49) on the OpenMoko appears to have a bug when sending the exit status back to the client. From time to time you receive an exit status of 255.

SSH Extras

If you get fed up with typing root@192.168.0.202, on your PC edit /etc/hosts and add an entry for 'phone'

192.168.0.202 phone

then edit ~/.ssh/config (or create it) and add

host phone
user root

then all you need to do is type

# ssh phone

You might want to use keys to bypass the login prompt too.

SSH Keys

From host to phone

To generate ssh keys for use as a login mechanism type

ssh-keygen -t rsa

when prompted for a password either hit enter for no password (not really a good idea) or enter a password for this key. ssh into the phone and create ~/.ssh

# mkdir ~/.ssh

then from your PC copy the .pub file to the phone.

# scp ~/.ssh/id_rsa.pub phone:.ssh/authorized_keys

You should now be able to ssh directly into the phone.

To disable password logins (after setting up key access) edit /etc/init.d/dropbear and change the following line:

DROPBEAR_EXTRA_ARGS=

to

DROPBEAR_EXTRA_ARGS="-s"

You will need to restart dropbear for this to take effect.

From phone to host

Generate the key

 dropbearkey -t rsa -f id_rsa

The output will look something like this:

 Will output 1024 bit rsa secret key to 'id_rsa'
 Generating key, this may take a while...
 Public key portion is:
 ssh-rsa AAAAB3Nza[...]
 Fingerprint: md5 ca:e8:f0:b7:f6:7b:c2:b6:b9:71:e4:45:86:a9:ff:b8

Copy and paste the one line (in this example, starting with 'ssh-rsa' onto the end of the host's authorized_keys file (often in ~/.ssh/).

From the phone, ssh with -i:

 ssh -i id_rsa user@host

This works for me. I ripped off these instructions from: [[1]]

GUI on desktop through SSH

If you need to get the GUI on the phone onto the desktop via usb, you can use ssh as follows

 ssh -l root -X -v 192.168.0.202

Login, and run openmoko-finger-demo for example, and it will open up on the desktop. To get landscape view, just resize the GUI window on the desktop.

Remote apps on neo

To get desktop apps to show up on your neo, first log in to the phone

 ssh -l root 192.168.0.202

Then once inside, run:

 DISPLAY=:0 xhost +192.168.0.200

After this you can close the ssh session. Back on the desktop computer, run:

 DISPLAY=moko:0 xclock

Note that the xhost command will allow remote applications on 192.168.0.200 to access the X server. It will allow anyone on the desktop machine to access the X server of the neo, including snooping anything you type on it. To disallow remote applications again, run this in the neo:

 DISPLAY=:0 xhost -192.168.0.200