Add multiboot USB post

2 files changed, 164 insertions, 0 deletions

diff --git a/md/writeup.md b/md/writeup.md
index 6960029..0743d93 100644
--- a/md/writeup.md
+++ b/md/writeup.md
@@ -8,6 +8,7 @@
 [Using GDB](writeup/using_gdb.md)  
 <!--[Compile Linux Kernel](writeup/compile_linux_kernel.md)-->
 [QEMU usage](writeup/qemu_usage.md)  
+[Multiboot USB drive](writeup/multiboot_usb_drive.md)
 
 ### Projects
 
diff --git a/md/writeup/multiboot_usb_drive.md b/md/writeup/multiboot_usb_drive.md
new file mode 100644
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+++ b/md/writeup/multiboot_usb_drive.md
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+# Multiboot USB drive
+
+Purpose of this is to use one USB driver to test many distros. When you have
+many distro ISO's it takes some time to _dd_ them on USB driver and if you
+whant to try many different then it will take time to _dd_ them everytime
+when you try new. If there is possible just copy many ISO's on USB driver and
+run any you need it will save you some time.
+
+## Lets install bootloader
+
+Using _fdisk_ to delete/create new partitions on USB drive
+
+```
+mkfs.vfat /dev/sdb1
+```
+
+mount drivet to current pc
+
+```
+mount /dev/sdb1 /mnt/flash0
+```
+
+create dire where will be grub files and grub menu config file
+
+```
+mkdir /mnt/flash0/boot
+```
+
+install grub, but you can install also 64bit grub if there is need
+
+```
+grub-install --target=i386-pc --recheck --boot-directory=/mnt/flash0/boot /dev/sdb
+```
+
+check with id have usb drive
+
+```
+blkid /dev/sdb1
+/dev/sdb1: UUID="D49E-18CC" TYPE="vfat" PARTUUID="5f55bd3d-01"
+```
+
+### Mounting ISO's
+
+Some manuals have outdatet filesystem layouts and there is need to investigate
+current layout by hand. And you need to mount ISO files.
+
+```
+mount -o loop /home/fam/downloads/iso/ubuntu-14.04.3-desktop-i386.iso /mnt/flash0
+```
+
+next is to check bootloader config how they are starting image, there you 
+can find extra options that need to be passed or just with image is used
+to start ISO
+
+## Boot menu 
+
+Here is result what you have at the end some Ubuntu isos, OpenWRT image and 
+your own compiled kernel
+
+__boot/grub/grub.cfg__
+
+```
+# Begin /boot/grub/grub.cfg
+set default=1
+set timeout=5
+
+probe -u $root --set=rootuuid
+set imgdevpath="/dev/disk/by-uuid/$rootuuid"
+
+menuentry "GNU/Linux, vmlinux" {
+        linux   /vmlinux root=/dev/disk/by-uuid/54F9-27A2 ro
+}
+
+
+menuentry "Ng-Linux, bzImage" {
+        linux   /bzImage root=/dev/disk/by-uuid/54F9-27A2 ro
+	initrd /test.cpio.gz
+}
+
+menuentry "OpenWRT, bzImage" {
+        linux   /openwrt-x86-generic-ramfs.bzImage root=/dev/sdb1 ro
+        initrd /openwrt-x86-generic-rootfs.cpio.gz
+}
+
+menuentry "DSL, bzImage" {
+	set isofile='/boot/iso/dsl-4.4.10.iso'
+	loopback loop $isofile
+        linux  (loop)/boot/isolinux/linux24 ramdisk_size=100000 init=/etc/init2 lang=us vga=normal atapicd nosound noscsi nousb nopcmcia nofirewire noagp nomce nodhcp xmodule=vesa 
+        initrd (loop)/boot/isolinux/minirt24.gz knoppix base norestore legacy
+}
+
+menuentry "Austrumi, bzImage" {
+        set isofile='/boot/iso/austrumi-3.2.6.iso'
+        loopback loop $isofile
+        linux  (loop)/austrumi/bzImage
+        initrd (loop)/austrumi/initrd.gz dolivecd text
+}
+
+menuentry '[loopback]archlinux-2015.12.01-dual.iso-mnth' {
+	set isofile='/boot/iso/archlinux-2015.12.01-dual.iso'
+	loopback loop $isofile
+	linux (loop)/arch/boot/x86_64/vmlinuz  img_dev=$imgdevpath img_loop=$isofile
+	initrd (loop)/arch/boot/x86_64/archiso.img
+}
+
+menuentry '[loopback]ubuntu-14.04.3-desktop-amd64' {
+	set isofile='/boot/iso/ubuntu-14.04.3-desktop-i386.iso'
+	loopback loop $isofile
+	linux (loop)/casper/vmlinuz boot=casper iso-scan/filename=$isofile locale=en_US.UTF-8
+	initrd (loop)/casper/initrd.lz
+}
+
+menuentry '[loopback]ubuntu-12.04.5-alternate-i386' {
+	set isofile='/boot/iso/ubuntu-12.04.5-alternate-i386.iso'
+	loopback loop $isofile
+	linux (loop)/install/vmlinuz boot=/dev/sda1 iso-scan/filename=$isofile locale=en_US.UTF-8
+	initrd (loop)/install/initrd.gz
+}
+
+menuentry "[loopback]tails-i386-1.8.1.iso" {
+    set isofile='/boot/iso/tails-i386-1.8.1.iso'
+    loopback loop $isofile
+    linux (loop)/live/vmlinuz2 boot=live config findiso=${isofile} live-media=removable apparmor=1 security=apparmor nopersistent noprompt timezone=Etc/UTC block.events_dfl_poll_msecs=1000 noautologin module=Tails
+    initrd (loop)/live/initrd2.img
+}
+
+```
+
+# Tested
+
+## Devices
+
+?Some images could be not loadable becouse not enought RAM?
+
+Tested to work on _Asus EEE PC 701_ [6]. And bigger desktop PC (12G RAM).
+
+| Distro  | Asus | PC  |
+|---|---|---|
+| my own kernel + initrd | + | + |
+| OpenWRT | + | - _?no kbd drivers_ |
+| DSL | - | - |
+| Austrumi | - | - |
+| archlinux 2015.12.01 | ? | + |
+| Ubuntu 14.04.3 | + |  + |
+| Ubuntu 12.04.5 | + | + |
+| Tails | ? | +  |
+
+```text
++ - works fine  
+- - doesnt work  
+? - to long to wait, not enought ram?  
+```
+
+# Links
+
+1. https://wiki.archlinux.org/index.php/Multiboot_USB_drive
+2. https://www.kernel.org/doc/Documentation/kernel-parameters.txt
+3. https://liquidat.wordpress.com/2007/10/15/short-tip-get-uuid-of-hard-disks/
+4. http://www.linuxfromscratch.org/lfs/view/stable/chapter08/grub.html
+5. http://www.redips.net/linux/create-fat32-usb-drive/
+6. https://en.wikipedia.org/wiki/Asus_Eee_PC
+
+