• Table of contents
• TestingInfrastructure
  • Applications that can be used to do some testing on the device
  • Projects and/or hardware that can be used to do functional testing
    • Lava
    • Labgrid
    • OsmoGSMTester
    • Simtrace2
  • Replicant supported devices and testing
    • Requirements
    • Galaxy SII (GT-I9100)
      • Example setup
      • Using a device without a battery.
      • Sumarry
  • USB modems
  • Pure software setup
    • lightweight test infrastructure for libsamsung-ipc
      • user mode Linux

TestingInfrastructure¶

Applications that can be used to do some testing on the device¶

• https://f-droid.org/wiki/page/org.zeroxlab.zeroxbenchmark

Projects and/or hardware that can be used to do functional testing¶

Lava¶

Lava can be used to do functional tests on real hardware. It can be easily installed on PureOS, an FSDG compliant GNU/Linux distribution.

Labgrid¶

Labgrid has features similar to Lava but it is probably easier to learn because it's probably way easier to get started with it.

OsmoGSMTester¶

The OsmoGSMTester project is able to be interfaced with the Android RIL through ofono and can emulate a GSM network with the help of a compatible GSM base station or SDR.

This presentation from 2019 has many insights on what kind of issue we might expect in interfacing it with smartphones.

Simtrace2¶

The Simtrace 2 project can be used, along with SIM card readers to programmatically feed a SIM card to a smartphone. This can be used to run test on real networks.

Replicant supported devices and testing¶

Requirements¶

• Antenna connector for the modem
• The ability to control the device buttons in order to be able to programmatically power on and off the device, and trigger boots into the bootloader and recovery
• Optionally a way to connect to the serial port, programmatically

Galaxy SII (GT-I9100)¶

• The Galaxy SII (GT-I9100) has:
  • An antenna connector. According to the External Antenna Socket - WARNING forum thread on XDA , it's an MS-162
  • The SOC serial port that is accessible behind the USB connector at a low voltage
  • A full size mini-sim (easier to interface with)

Holding the smartphone in place:

• The smartphone could either be screwed on a metallic surface or an external case could be screwed on a metallic surface enabling the smartphone not to move.

SIM cards:

• Simtrace and Simtrace 2 both lacks screw holes so a way must be found to make sure that it doesn't move as it uses flex cables to interface with the SIM socket of the smartphone. That may be fixed in a subsequent hardware revision.

Serial port and USB:

Buttons:

Battery:

Antenna connector and GSM tower or SDR:
The Galaxy SII (GT-I9100) has two antenna connectors:

• One internal connector, TODO: find the connector type
• One external connector, TODO: Find the connector type

Example setup¶

See also the links inside the Serial_port article for more background on how to get serial port access on devices like the Galaxy SIII (GT-I9300) or the Galaxy SII (GT-I9100).

See https://git.replicant.us/contrib/GNUtoo/test-infrastructure.git for the source of the file.

Using a device without a battery.¶

• How to use a Galaxy SIII without a battery : It doesn't look very safe to do that as the phone is probably not expecting 5V on the battery connector but it gives some idea of the peak tolerances.

• The Galaxy SIII 4G (GT-I9305) could probably work at lower voltages like 3.3V through the battery connector, but it would require testing it. In that case it might also be a good idea to test it in all configurations (all hardware features being used, cpuburn etc).

• The 4 pin 'FPC' style battery connector available from amazon, marketed as being for the 'S4 value edition i9515' (https://amazon.de/gp/product/B0813JBW8S) is capable of contacting the Galaxy SIII (GT-I9300)'s battery.

Sumarry¶

Device	Modem antenna connector	Compatible software	Comments
Motorolla C155	MS-147	* OsmocomBB * Old Nuttx revisions	Could be used as reference phone as it's probably already supported by the Osmocom testing infrastructure
Galaxy SII (GT-I9100)	MS-162	* Replicant 4.0, 4.2, 6.0 * Upstream Linux (partial)
Galaxy Nexus (GT-I9250)	?	* Replicant 4.0, 4.2, 6.0	We can get some GSM traces in wireshark with xgoldmon
Galaxy SIII (GT-I9300)	?	* Replicant 4.0, 4.2, 6.0 * Upstream Linux (partial)

USB modems¶

When trying to enable protocol tracing in modems we can connect the device modem (somewhat directly) to a laptop

Questions:

• Do we have samsung-ipc on top of the virtual UARTs?
• The cbd daemon mentioned in the blog post about booting the Galaxy S7 modem doesn't list UART as main link though.
• Adding the modem USB id when in debug mode (1519:0020) in a search engine shows various usb keys
• Do phones like the Galaxy SII have smasung-ipc on top of the USB link or UART links when in debug mode?

Pure software setup¶

lightweight test infrastructure for libsamsung-ipc¶

It might be possible to have a pure software test infrastructure with libsamsung-ipc.

It could be done more or less like that:

test script <-> ipc-modem or other programs <-> libsamsung-ipc <-> Linux kernel <-> VHCI <-> software sending USB packets

We have several choices for the Linux kernel:

Kernels	Comments
User mode Linux (ARCH=um)	(+) Very lightweight, runs completely in userspace (-) Requires patches for USB / VHCI
Linux + libvirt + kvm	(-) Require some virtualization setup that requires dedicated RAM (+) Probably works unpatched

And there is already some projects emulating usb devices:

Project	Description	comments
gnuk	USB token software	can build for gnulinux
choptix	Library used by gnuk	More simple examples
simtrace2 ?	SIM tracing and MITM tool	Probably uses vusb for testing too

So it might be possible to modify them to send some simple USB packets captured with wireshark / tshark / tcpdump.

user mode Linux¶

I've already managed to find a configuration that works in an FSDG compliant way:

Settings	Status
kernel: kernel_replicant_linux (replicant-11-test branch at the time of writing) compilation settings: ARCH=um Host architecture: x86_64 kernel defconfig: x86_64_defconfig Target Distribution: Parabola x86_64 commandline arguments: ./linux mem=2047M ubd0=parabola.img root=/dev/ubda1	Boots fine
kernel: kernel_replicant_linux or upstream Linux compilation settings: ARCH=um Host architecture: i686 or x86_64 kernel defconfig: i686_defconfig	Fails to compile

To run Parabola first you need to create an image.
Then you need to chroot (with arch-chroot) insde the image and change the password.
Once you exited the chroot and unmounted the image and removed the loop mapping, you can boot it.

During boot you'll see a message like that at the end:

Virtual console 1 assigned device '/dev/pts/4'

You can then login in this way:

$ sudo picocom /dev/pts/4 
picocom v3.1

port is        : /dev/pts/4
flowcontrol    : none
baudrate is    : 9600
parity is      : none
databits are   : 8
stopbits are   : 1
escape is      : C-a
local echo is  : no
noinit is      : no
noreset is     : no
hangup is      : no
nolock is      : no
send_cmd is    : sz -vv
receive_cmd is : rz -vv -E
imap is        : 
omap is        : 
emap is        : crcrlf,delbs,
logfile is     : none
initstring     : none
exit_after is  : not set
exit is        : no

Type [C-a] [C-h] to see available commands
Terminal ready

parabola login: root
Password: 
[root@parabola ~]# cat /etc/os-release 
NAME="Parabola" 
PRETTY_NAME="Parabola GNU/Linux-libre" 
ID=parabola
ID_LIKE=arch
BUILD_ID=rolling
ANSI_COLOR="1;35" 
HOME_URL="https://www.parabola.nu/" 
DOCUMENTATION_URL="https://wiki.parabola.nu/" 
SUPPORT_URL="irc://chat.freenode.net#parabola" 
BUG_REPORT_URL="https://labs.parabola.nu/" 
LOGO=parabola
[root@parabola ~]# 

TODO:

• We probably need to make i686 and armv7 to work too.
• We need to find and port the USB patches on top of kernel_replicant_linux
• We also need to setup USB somehow with vhci_hcd and so on
• We still need to find a very simple stack to send URBs.