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diff --git a/i18n/fr_FR/docs/gnulinux/grub_cbfs.md b/i18n/fr_FR/docs/gnulinux/grub_cbfs.md new file mode 100644 index 00000000..f6c99332 --- /dev/null +++ b/i18n/fr_FR/docs/gnulinux/grub_cbfs.md @@ -0,0 +1,398 @@ +--- +title: Modifying the GRUB Configuration in Libreboot Systems +x-toc enable: true +... + + +This guide will go through all the steps to modify a GRUB configuration file +in Libreboot; this is so that the user doesn't have to manually boot +their operating system each time, by typing in commands at the GRUB command line. + +For the purposes of this guide, you can either modify the GRUB configuration file +that resides in the computer's ROM, or else you could modify the version that +exists within the operating system itself; both options will be explained here. + +## How to Get the GRUB Configuration File +The first step of the process is to actually get a hold of the GRUB configuration file +that we need to modify. There are two ways to do this: + +1. We can extract the one that already exists within the ROM +2. We can use one of the pre-compiled ROMS supplied by the Libreboot project + +However, both ways will require us to download the Libreboot Utility Archive. + +### Download the Libreboot Utility Archive +The Libreboot Utility Archive contains the programs that we'll need +to get our **grubtest.cfg** file. The latest release of the Libreboot Utility Archive +can be downloaded [from libreboot.org](https://www.mirrorservice.org/sites/libreboot.org/release/stable/20160907/libreboot_r20160907_util.tar.xz). +The quickest way to download it would be to use the `wget` program, +which (if you don't know) allows you to download files from the internet. + +If you don't already have it installed, you can install it, +using the `apt-get` command (in Debian-based distributions): + + $ sudo apt-get install wget + +You can install it in Arch-based systems, using `pacman`: + + $ sudo pacman -S wget + +Once you've installed `wget`, use it to download the file, +simply by passing it the URL as an argument; you can save the file anywhere, +but for the purpose of this guide, save it in **~/Downloads** +(your **Home** directory's downloads folder). +First, change the current working directory to **~/Downloads**: + + $ cd ~/Downloads + +This guide assumes you are using the **20160907** version of Libreboot; +if using a different version, modify the following commands accordingly: + + $ wget https://www.mirrorservice.org/sites/libreboot.org/release/stable/20160907/\ + >libreboot_r20160907_util.tar.xz + +After the file is downloaded, use the `tar` command to extract its contents: + + $ tar -xf libreboot_r20160907_util.tar.xz + +After extraction, the folder will have the same name as the archive: in this case, +**libreboot\_r20160907\_util**. For simplicity's sake, we'll rename it **libreboot\_util**, +using the `mv` command: + + $ mv "libreboot_r20160907_util" "libreboot_util" + +Now you have the folder with all the utilities necessary to read and modify the contents of the ROM. + +### Get the Necessary Utilities +Once you have the **libreboot\_util** archive, you can find the `cbfstool` and `flashrom` +utilities in **libreboot\_util/cbfstools/x86\_64/cbfstool**, +and **libreboot\_util/flashrom/x86\_64/flashrom**, respectively. + +**NOTE: This guide assumes that you are using a device with the** x86\_64 **architecture; +if you are using a device with a different architecture (e.g.,** i686 **or** armv7l**), +the proper version of** `cbfstool` **and** `flashrom` **will be in that folder, +inside their respective directories.** + +You could also compile both of these utilities; see [How to Build flashrom](../git/#build_flashrom). + +`flashrom` is also available from the repositories; if using an Arch-based distribution, +use `pacman`: + + $ sudo pacman -S flashrom + +Or, if you have a Debian-based distribution, use `apt-get`: + + $ sudo apt-get install flashrom + +### Get the ROM Image +You can either work directly with one of the ROM images already included +in the libreboot ROM archives, or re-use the ROM that you have currently +flashed. For the purpose of this tutorial, it is assumed that your ROM +image file is named **libreboot.rom**, so please make sure to adapt. + +There are two ways to get a pre-compiled ROM image: + +#### 1. Download a Pre-Compiled Image from the Libreboot Website +For the current release, **20160907**, they can be found [on a Libreboot mirror](https://www.mirrorservice.org/sites/libreboot.org/release/stable/20160907/rom/grub/); +please adopt this guide, if using a different version of Libreboot. + +You also need to make sure that you select both the correct ROM for the device you're using, +as well as the correct flash chip size (if applicable): **4mb**, **8mb**, or **16mb**; +variable flash chip sizes only apply for the Thinkpads that Libreboot supports (excluding the X60 and T60). + +You can find the flash chip size, by running the following command: + + # flashrom -p internal + +Look for a line like this: + + Found Macronix flash chip "MX25L6406E/MX25L6408E" (8192 kB, SPI) \ + mapped at physical address 0x00000000ff800000. + +Running this command on my Thinkpad X200 gives me the above result, so I know that +my flash chip size is **8mb**. + +Once you've determined the correct ROMs and flash chip size, download them from the website. +Since I'm currently using an X200 to write this guide, I'll demonstrate how +to download the correct ROM images for that model. + +First, we're going to navigate to the **libreboot\_util** folder: + + $ cd ~/Downloads/libreboot_util/ + +Then, we will download the ROM images, using `wget`: + + $ wget https://www.mirrorservice.org/sites/libreboot.org/release/stable/\ + >20160907/rom/grub/libreboot_r20160907_grub_x200_8mb.tar.xz + +Extract the archive, using `tar`: + + $ tar -xf libreboot_r20160907_grub_x200_8mb.tar.xz + +Navigate to the directory that you just created: + + $ cd libreboot_r20160907_grub_x200_8mb + +Now that we are in the archive, we must choose the correct ROM image. +To figure out the correct image, we must first parse the filenames for each ROM. +For example, for the file named **x200_8mb_usqwerty_vesafb.rom**: + + Model Name: x200 + Flash Chip Size: 8mb + Country: us + Keyboard Layout: qwerty + ROM Type: vesafb or txtmode + +Since I am using a QWERTY keyboard, I will ignore all the non-QWERTY options. +Note that there are two types of ROMs: **vesafb** and **txtmode**; +The **vesafb** ROM images are recommended, in most cases; **txtmode** ROM images +come with `MemTest86+`, which requires text-mode, instead of the usual framebuffer +used by coreboot native graphics initialization. + +I'll choose **x200_8mb_usqwerty_vesafb.rom**; I'll copy the file (to the `cbfstool` directory), +and rename it with one command: + + $ mv "x200_8mb_usqwerty_vesafb.rom" ../cbfstool/x86_64/libreboot.rom + +#### 2. Create an Image from the Current ROM +The simpler way to get a ROM image is to just create it from your current ROM, +using `flashrom`, making sure to save it in the `cbfstool` folder, inside **libreboot\_util**: + + $ sudo flashrom -p internal -r ~/Downloads/libreboot_util/cbfstool/x86_64/libreboot.rom + +If you are told to specify the chip, add the option `-c {your chip}` to the command, like this: + + $ sudo flashrom -c MX25L6405 -p internal -r ~/Downloads/libreboot_util/cbfstool/x86_64/libreboot.rom + +Now you are ready to extract the GRUB configuration files from the ROM, and modify them the way you want. + + +### Copy grubtest.cfg from the ROM Image +You can check the contents of the ROM image, inside CBFS, using `cbfstool`. +First, navigate to the cbfstool folder: + + $ cd ~/Downloads/libreboot_util/cbfstool/x86_64/ + +Then, run the `cbfstool` commmand, with the `print` option; this will display +a list of all the files located in the ROM: + + $ ./cbfstool libreboot.rom print + +You should see **grub.cfg** and **grubtest.cfg** in the list. **grub.cfg** is +loaded by default, with a menu entry for switching to **grubtest.cfg**. In +this tutorial, you will first modify and test **grubtest.cfg**. This is to +reduce the possibility of bricking your device, so *DO NOT SKIP THIS!* + +Extract (i.e., get a copy of ) **grubtest.cfg** from the ROM image: + + $ ./cbfstool libreboot.rom extract -n grubtest.cfg -f grubtest.cfg + +By default `cbfstool` will extract files to the current working directory; +so, **grubtest.cfg** should appear in the same folder as **libreboot.rom**. + +## How to Modify the GRUB Configuration File +This section will instruct the user *how* to modify their GRUB configuration file; +whether they decide to use the version located in their operating system's **/** folder, +or the one located in the ROM, the modifications will be the same. + +Once the file is open, look for the following line (it will be towards the bottom of the file): + + menuentry 'Load Operating System [o]' --hotkey='o' --unrestricted + +After this line, there will be an opening bracket **{**, followed by a several lines +of code, and then a closing bracket **}**; delete everything that is between those two brackets, +and replace it with the following code, if you're using an Arch-based disribution (e.g., Parabola GNU+Linux-Libre): + + cryptomount -a + set root='lvm/matrix-root' + linux /boot/vmlinuz-linux-libre root=/dev/matrix/root cryptdevice=/dev/sda1:root \ + cryptkey=rootfs:/etc/mykeyfile + initrd /boot/initramfs-linux-libre.img + +Or, replace it with this, if you are using a Debian-based distribution (e.g., Trisquel GNU+Linux): + + cryptomount -a + set root='lvm/matrix-rootvol' + linux /vmlinuz root=/dev/mapper/matrix-rootvol cryptdevice=/dev/mapper/matrix-rootvol:root + initrd /initrd.img + +Remember, that these names come from the instructions to install GNU+Linux +on Libreboot systems, located [in the docs](index.md). If you followed different instructions, +(or for some other reason, used different names), simply put the names +of your **root** and **swap** volumes, in place of the ones used here. + +This covers the basic changes that we can make to GRUB; however, there are some more +changes that you could make, to increase the security of your GRUB configuration. +If you are interested in those modifications, see the Libreboot guide on [Hardening GRUB](grub_hardening.md). + +That's it for the modifications! Now all you need to do is follow the instructions below, +in order to use this new configuration to boot your system. + +## Change the GRUB Configuration File that the Operating System Uses +Now that we have explained *how* to modify the file itself, we need to explain +how to actually make our system *use* the new GRUB configuration file to boot. + +### Without Re-Flashing the ROM +To change the GRUB Configuration that our system uses, without having to re-flash the ROM, +we need to take our **grubest.cfg** file, rename it to **libreboot\_grub**; +this is because that, by default, GRUB in Libreboot is configured to scan all partitions on +the main storage for **/boot/grub/libreboot\_grub.cfg** or **/grub/libreboot\_grub.cfg** +(for systems where **/boot** is on a dedicated partition), and then use it automatically. + +Therefore, we need to either copy **libreboot\_grub.cfg** to **/grub**, or to **/boot/grub**: + + $ sudo cp ~/Downloads/libreboot_util/cbfstool/x86_64/libreboot_grub.cfg /boot/grub # or /grub + +Now, the next time we boot our computer, GRUB (in Libreboot) will automatically switch +to this configuration file. *This means that you do not have to re-flash, +recompile, or otherwise modify Libreboot at all!* + +### With Re-Flashing the ROM +Changing the GRUB configuration that resides in ROM is a bit more complicated +that the one in **/**, but most of the hard work is already done. + +#### Change grubtest.cfg in ROM +Now that you have the modified **grubtest.cfg**, we need to remove +the old **grubtest.cfg** from the ROM, and put in our new one. To remove +the old one, we will use `cbfstool`: + + $ ./cbfstool libreboot.rom remove -n grubtest.cfg + +Then, add the new one to the ROM: + + $ ./cbfstool libreboot.rom add -n grubtest.cfg -f grubtest.cfg -t raw + +#### Change MAC address in ROM {#changeMAC} +The last step before flashing the new ROM, is to change the MAC address inside it. +Every libreboot ROM image contains a generic MAC address; you want to make sure +that your ROM image contains yours, so as to not create any problems on your network +(say, for example, that multiple family members had libreboot computers, and used +the same ROM image to flash those computers). + +To do this, we will use the `ich9gen` utility, also located in **libreboot_util**. + +First, you need to find the current MAC address of your computer; there are +two ways to do this: + +1. Read the white label on the bottom of the case (however, this will only work, +if your motherboard has never been replaced). +2. Run `ifconfig`; look for your ethernet device (e.g., **enpXXX** +in Arch-based distributions, or **eth0** in Debian-based distributions), +and look for a set of characters like this: `00:f3:f0:45:91:fe`. + +Next, you need to move **libreboot.rom** to the following folder; this is where +the executable for `ich9gen` is located: + + $ mv libreboot.rom ~/Downloads/libreboot_r20160907_util/ich9deblob/x86_64 + +Once there, run the following command, making sure to use your own MAC address, +instead of what's written below: + + $ ./ich9gen --macaddress XX:XX:XX:XX:XX:XX + +Three new files will be created: + +* **ich9fdgbe_4m.bin**: this is for GM45 laptops with the 4MB flash chip. +* **ich9fdgbe_8m.bin**: this is for GM45 laptops with the 8MB flash chip. +* **ich9fdgbe_16m.bin**: this is for GM45 laptops with the 16MB flash chip. + +Look for the one that corresponds to the size of your ROM image; for example, +if your flash chip size is **8mb**, you'll want to use **ich9fdgbe_8m.bin**. + +Now, insert this file (called the `descriptor+gbe`) into the ROM image, using `dd`: + + $ dd if=ich9fdgbe_8m.bin of=libreboot.rom bs=1 count=12k conv=notrunc + +Move **libreboot.rom** back to the **libreboot\_util** directory: + + $ mv libreboot.rom ~/Downloads/libreboot_util + +You are finally ready to flash the ROM! + +#### Flash Updated ROM Image +The last step of flashing the ROM requires us to change our current working directory +to **libreboot\_util**: + + $ cd ~/Downloads/libreboot_util + +Now, all we have to do is use the `flash` script in this directory, +with the `update` option, using **libreboot.rom** as the argument: + + $ sudo ./flash update libreboot.rom + +Ocassionally, coreboot changes the name of a given board. If `flashrom` +complains about a board mismatch, but you are sure that you chose the +correct ROM image, then run this alternative command: + + $ sudo ./flash forceupdate libreboot.rom + +You will see the `flashrom` program running for a little while, and you might see errors, +but if it says `Verifying flash... VERIFIED` at the end, then it’s flashed, +and should boot. If you see errors, try again (and again, and again). +The message, `Chip content is identical to the requested image` is also +an indication of a successful installation. + +#### Reboot the Computer +Now that you have flashed the image, reboot the computer. Keep pressing `spacebar` +right after you turn it on, until you see the GRUB menu, to prevent libreboot +from automatically trying to load the operating system. + +Scroll down with the arrow keys, and choose the `Load test configuration (grubtest.cfg) inside of CBFS` option; +this will switch the GRUB configuration to your test version. If all goes well, +it should prompt you for a GRUB username and password, and then your LUKS password. + +Once the operating system starts loading, it will prompt you for your LUKS password again. +If it continues, and loads into the OS without errors, then that means your flashing +attempt was a success. + +#### Final Steps +When you are satisfied booting from **grubtest.cfg**, you can create a copy +of **grubtest.cfg**, called **grub.cfg**. + +First, go to the `cbfstool` directory: + + $ cd ~/Downloads/libreboot_util/cbfstool/x86_64/ + +Then, create a copy of **grubest.cfg**, named **grub.cfg**: + + $ cp grubtest.cfg ./grub.cfg + +Now you will use the `sed` command to make several changes to the file: +the menu entry `'Switch to grub.cfg'` will be changed to `Switch to grubtest.cfg`, +and inside it, all instances of **grub.cfg** to **grubtest.cfg**. +This is so that the main configuration still links (in the menu) to **grubtest.cfg**, +so that you don't have to manually switch to it, in case you ever want to follow +this guide again in the future (modifying the already modified config).: + + $ sed -e 's:(cbfsdisk)/grub.cfg:(cbfsdisk)/grubtest.cfg:g' -e \ + >'s:Switch to grub.cfg:Switch to grubtest.cfg:g' < grubtest.cfg > \ + >grub.cfg + +Move **libreboot.rom** from **libreboot\_util** to your current directory: + + $ mv ~/Downloads/libreboot_util/libreboot.rom . + +Delete the **grub.cfg** that's already inside the ROM: + + $ ./cbfstool libreboot.rom remove -n grub.cfg + +Add your modified **grub.cfg** to the ROM: + + $ ./cbfstool libreboot.rom add -n grub.cfg -f grub.cfg -t raw + +Move **libreboot.rom** back to **libreboot\_util**: + + $ mv libreboot.rom ../.. + +If you don't remember how to flash it, refer back to the *Flash Updated ROM Image*, above; it's the same method as you used before. Afterwards, reboot the machine with your new configuration. + +Copyright © 2014, 2015, 2016 Leah Rowe <info@minifree.org> + +Copyright © 2017 Elijah Smith <esmith1412@posteo.net> + +Permission is granted to copy, distribute and/or modify this document +under the terms of the GNU Free Documentation License Version 1.3 or any later +version published by the Free Software Foundation +with no Invariant Sections, no Front Cover Texts, and no Back Cover Texts. +A copy of this license is found in [../fdl-1.3.md](../fdl-1.3.md) + |