Activation and developer keys

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A developer key is a file containing cryptographic information tied to a specific XO laptop.

What you can do with a developer key

If the boot firmware sees a developer key, it makes the XO laptop work just like any ordinary PC-style laptop, in the sense that it will let you interrupt the boot process and enter commands; and it will try to boot and run any program you supply to it, no matter whether the OLPC organization has tested or signed it. The laptop also works this way if its firmware security is disabled. OLPC produces many unsigned "development builds" of the operating system, which will only work in your laptop if you have a developer key. Also, if your laptop refuses to boot because the clock is set wrong, or complains about an unsigned kernel, getting a developer key is a critical part of diagnosing and/or fixing the trouble.

If you don't have a developer key, and the laptop has firmware security enabled, it will not let you do anything except boot the operating system and use the provided software. If you insert a USB memory stick or SD card, the boot firmware will only boot from it if the files are tested and cryptographically signed by OLPC.

Some laptops sent to schools in developing countries have firmware security enabled, depending on the wishes of that country's education system. Laptops that were sent to Give One, Get One donors also have firmware security enabled.

  1. The firmware will look for a developer key on your laptop's internal flash memory; on any USB memory stick that's plugged in; and on any SD card that's plugged in. It needs to be in /security (See Firmware Security for the gory details.)
  2. With a developer key, whenever the laptop boots, the firmware will give you the option to hit Escape (the upper left key, marked with an X in a circle) and get an ok prompt, which lets you enter commands in Forth. If you don't press Escape, after a short countdown the firmware continues booting the operating system.
    • This is the insecure boot process, and it will boot into any image you install on the xo.
    • Rather than drawing pretty pictures on the screen, lots of text messages will be displayed, and will eventually scroll up the screen. This is normal, and can be useful for diagnosing problems in your laptop.
    • The insecure boot process does not automatically upgrade firmware; you will be responsible for updating your firmware yourself.

Disabling security

One of the commands you can enter will enable this situation permanently, even without a developer key. This process is reversible.

  1. If you type 'disable-security' at the ok prompt, firmware security will be turned off on your laptop permanently. (This isn't necessary, but in some cases useful; see below.)
    • If you ever do a fresh install of the operating system (a complete overwrite of the internal flash memory; i.e. not olpc-update), you will lose the developer key (stored in /security/develop.sig). If you haven't disabled security, and if the build you overwrote with isn't signed, your laptop won't boot by default. You can either reflash again with a signed image to recover, or insert a USB memory stick or SD card with your developer key on it (this is why you should always be sure to backup develop.sig).
    • Even if security is disabled, you can re-enable it for a single boot by pressing the X gamepad key while turning the power on. This is useful to do firmware upgrades from signed builds. It can also help to test secure boot on release candidates.
    • You can reverse the 'disable-security' command with 'enable-security' at the ok prompt.

Getting a developer key for your running XO laptop

  1. On the XO, open the Browse activity.
  2. There's a "Developer key request" web page on the XO to apply for a key. There are several ways to navigate to this page (<trac>6314</trac> wonders if the library on the XO should be reorganized):
    • In Ship.1, Click on the Library link "other" and then on "about your xo". Click on the "apply for a developer key" link at the very bottom of the page. (You can press the 'check mark' (✓) game key to quickly get to the bottom of the page.)
    • In newer builds (Update.1, 703 and higher), click "Activities" in the OLPC Library left-hand navigation, click on the sub-menu "find activities", and at the bottom of the page that displays is the "apply for developer key" link.
    • In newer builds (Update.1, 703 and higher), you can also click "Books" in the OLPC Library left-hand navigation, click on the sub-menu "explore your xo", click "troubleshooting", and under "How do I get a developer key for my laptop" is a link to "submit this form"
    • You can also just type file:///home/.devkey.html in the browse location field to get to this form.
  3. Follow the directions to apply for a developer key.
  4. The key should be created within a day or two.
  5. Go back to the page when your key is ready, and follow the instructions for downloading your key. Once the key has been created, you can return to this page at any time to re-download it; there will be no further creation delay.
  6. Reboot your xo.
  7. Please make a copy of your developer key on some other computer, one that gets backed up regularly, in case this one is lost. You may want to copy your developer key from /security/develop.sig on the build in NAND flash to /security/develop.sig on a USB key or SD card, in case you need it later.

Tip for those of you, like me, who cannot read the small typeface used in the webpage returned by the activation server: copy the text and paste it into the Write activity, where you can resize it. (This not not necessary on newer builds that have copy/paste enabled in the Terminal activity.)

Getting a developer key without WiFi

You can do any of the following:

  • use a USB-to-wired ethernet adapter to get your XO on the net, then follow the above instructions.
  • you can copy the file /home/.devkey.html from the XO to another (network-connected) machine, and perform the process from that machine. Entering the following command in the Terminal activity will copy it to any USB devices connected:
    • cp -p /home/.devkey.html /media/*/devkey.html
  • You can submit a written request via snail mail.
    The contact address on the OLPC website should work:
    One Laptop per Child
    P.O. Box 425087
    Cambridge, MA 02142
  • Follow the instructions below:

Getting a developer key without network

If the machine won't boot

First, try booting with the 'O' (circle) gamepad key held down. That will attempt to boot a previous version of the OS; if your problem was that you attempted to update to an unsigned kernel without a developer key, this will get you running again, and you can use the easier developer key mechanisms above.

Otherwise, you need to go the slow way. It requires a USB memory stick, and manual assistance from someone at OLPC. To start the process, you will need to provide OLPC with both the Serial Number of your machine, and its UUID. The Serial Number is conveniently printed on a sticker in the battery compartment, and looks like "CSN74701E2F". The UUID is unfortunately only stored internally. To get it, you'll have to download a pair of signed Forth "Collector scripts" onto a USB memory stick (see below), plug it into your laptop, power it on, let it do its thing, and then remove the USB stick and use a different computer to send the resulting laptops.dat file to OLPC. That process is described below. How the Serial Number and UUID in the laptops.dat file turns into a developer key is still a manual process. Until we improve the "back end" of this operation, please just send email to help@laptop.org that describes your problem, includes the serial number, and attaches the resulting laptops.dat file.

Collecting serial numbers and UUID's for one or many XOs

First, you must create a 'Collection stick':

  1. Download Actos.zip and Runos.zip (its source code in Forth, if you're interested, is at http://dev.laptop.org/git?p=users/cscott/actkey; it will only run if it's put into a signed zip file.)
    • Actos.zip and Runos.zip are identical, but secure boot will use one or the other depending on your laptop's activation status, which we may not know. So include both.
  2. Put these files in a directory called 'boot' on a FAT-formatted or FAT32-formatted USB memory stick.
    • Most memory sticks use FAT or FAT32 when you buy them (except "U2" memory sticks which probably won't work; they contain ugly DRM stuff).
  3. So your USB memory stick will contain these files (and nothing else in the boot directory):
    • boot/
    • boot/Actos.zip
    • boot/Runos.zip
  4. If there is an old laptops.dat file on the USB stick from an earlier collection of laptops, delete it.
    • The memory stick can have any other files on it that you like.

Now, for each laptop that you want to get a Developer Key for (maybe only one):

  1. Insert the 'Collection stick' in one of the USB ports on the laptop.
  2. Power it on with the power key.
    • This will put your Serial Number and UUID into the laptops.dat file on the 'Collection stick' (it creates the file if it needs to).
  3. It will display a pretty "XO" screen and then a short message like "SHFxxxxxxxx nnnnnnnnnnnnnnn; Laptop data recorded successfully". After a few seconds it will power itself off.
  4. When the machine powers itself off, remove the 'Collection stick'.

Do the above with each laptop in turn that you want to create keys for (in most cases, only one laptop). The 'Collection stick' will append the information for each new laptop to the laptops.dat file, so do not delete the laptops.dat file in between.

When you're done, plug the 'Collector stick' into another computer, and send the collected information to OLPC. If you haven't been instructed any other way to send it, put it in an email to help@laptop.org, tell us that you need a developer key for laptop(s) that won't boot, and insert or attach the laptops.dat file into the email message. If you have already interacted with help@laptop.org about this laptop, just reply to their last message to you, so your laptops.dat file will go into the same trouble ticket as the rest of your trouble report.

Then wait for OLPC to send you your Developer key(s) and/or Activation key(s).

What to do when you receive your activation or developer keys

  1. You can use the same USB memory stick that you used as 'Collector stick', but rename the "boot" directory to something else (perhaps "collboot"), otherwise your laptop will just re-run the collection script.
  2. You'll receive one or two files from OLPC, probably by email. Extract the file or files using your email program.
  3. If you receive a lease.sig file, it's your activation key. (G1G1 laptops don't need one.) Copy the activation key (lease.sig) into the root directory of your USB memory stick.
  4. Make a directory called security in the root directory of your USB memory stick.
  5. Copy the developer key (develop.sig) into the security directory on the USB memory stick.
    • When you're done, these files will be there:
      • lease.sig (only if received)
      • security/
      • security/develop.sig
  6. OLPC may also send you other files to put on the memory stick, e.g. to help to patch or circumvent whatever problem is preventing your laptop from booting properly.
  7. With the laptop powered off, insert the USB memory stick in one of its USB ports.
  8. Power on the laptop.
  9. If the laptop wasn't previously activated... it will now boot properly
    • Any provided activation key will be copied to /security/lease.sig on the XO. You may want to keep the activation key around (or copy the activation key to your school server, if you have one) in case you ever need to wipe the XO and reflash it.
  10. If you're using the developer key, you should be able to get to the ok prompt, which you will see within the first few seconds of booting (along with a short countdown to give you time to hit the Escape key). This is your indication that the developer key has been found.
  11. The developer key is not automatically copied to your laptop's internal flash memory. You can do that once you have Linux running on it, by copying security/develop.sig from the USB memory stick into /security/develop.sig in the root filesystem of the laptop. You'll need a root shell to do that; it can't be done from the Journal or the GUI.
  12. If the laptop is running Linux, go into the Journal, position the mouse over the USB stick image at the bottom of the screen, wait until it pops up an "Unmount" button, then click on that. Wait until it has finished and doesn't show the USB stick image any more. Then it's safe to remove the USB stick from that laptop.
  13. If the laptop is at an "ok" prompt in the boot firmware, it's safe to remove the USB stick immediately.

If you submitted information for more than one laptop, you can then put the USB memory stick into the next laptop, and repeat the above process. The same memory stick, with the same lease.sig and develop.sig files, should work for all the laptops you included in the laptops.dat file.


See also

Note: the Developer key page generated by the OLPC Activation Service (in response to a developer key request from the XO) links to this page.

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