From f6c317b38bf576f0d8d49ef21f8272d273d126b6 Mon Sep 17 00:00:00 2001
From: Nilstrieb <48135649+Nilstrieb@users.noreply.github.com>
Date: Sat, 17 Feb 2024 14:35:16 +0100
Subject: [PATCH] create disks

---
 .envrc                       |  1 +
 .gitignore                   |  1 +
 debian-image/create_image.sh | 76 ++++++++++++++++++++++++++++++++++++
 debian-image/reset.sh        |  7 ++++
 debian-image/setup.sh        | 48 +++++++++++++++++++++++
 shell.nix                    |  3 ++
 6 files changed, 136 insertions(+)
 create mode 100644 .envrc
 create mode 100644 .gitignore
 create mode 100755 debian-image/create_image.sh
 create mode 100755 debian-image/reset.sh
 create mode 100755 debian-image/setup.sh
 create mode 100644 shell.nix

diff --git a/.envrc b/.envrc
new file mode 100644
index 0000000..1d953f4
--- /dev/null
+++ b/.envrc
@@ -0,0 +1 @@
+use nix
diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..a55bd1f
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+/debian-image/build
diff --git a/debian-image/create_image.sh b/debian-image/create_image.sh
new file mode 100755
index 0000000..89b838d
--- /dev/null
+++ b/debian-image/create_image.sh
@@ -0,0 +1,76 @@
+#!/usr/bin/env bash
+
+# https://mvallim.github.io/kubernetes-under-the-hood/documentation/create-linux-image.html
+
+SCRIPT=$(dirname "$0")
+BUILD="$SCRIPT/build"
+IMAGE="$BUILD/debian-image.raw"
+
+mkdir -p "$BUILD"
+
+if ! [ -f "$IMAGE" ]; then
+  # Create a 30GB disk
+  dd \
+    if=/dev/zero \
+    of="$IMAGE" \
+    bs=1 \
+    count=0 \
+    seek=32212254720 \
+    status=progress
+
+  sed -e 's/\s*\([\+0-9a-zA-Z]*\).*/\1/' << EOF | sudo fdisk "$IMAGE"
+o # clear the in memory partition table
+n # new partition
+p # primary partition
+1 # partition number 1 
+    # default - start at beginning of disk
++512M # 512 MB boot parttion
+n # new partition
+p # primary partition
+2 # partion number 2
+    # default, start immediately after preceding partition
+    # default, extend partition to end of disk
+a # make a partition bootable
+1 # bootable partition is partition 1 -- /dev/loop0p1
+p # print the in-memory partition table
+w # write the partition table
+q # and we're done
+EOF
+else
+  echo "INFO: Skipping disk creation"
+fi
+
+if ! [ -e "/dev/loop0" ]; then
+  sudo losetup -fP "$IMAGE"
+  sudo losetup -a
+
+  sudo fdisk -l /dev/loop0
+  sudo mkfs.ext4 /dev/loop0p1 # /boot
+  sudo mkfs.ext4 /dev/loop0p2 # /
+else
+  echo "INFO: Skipping loop device setup"
+fi
+
+
+mkdir -p "$BUILD/chroot"
+sudo mount /dev/loop0p2 "$BUILD/chroot/"
+
+if ! [ -d "$BUILD/chroot/bin" ]; then
+  sudo debootstrap \
+    --arch=amd64 \
+    --variant=minbase \
+    --components "main" \
+    --include "ca-certificates,cron,iptables,isc-dhcp-client,libnss-myhostname,ntp,ntpdate,rsyslog,ssh,sudo,dialog,whiptail,man-db,curl,dosfstools,e2fsck-static" \
+    bookworm \
+    "$BUILD/chroot" \
+    http://deb.debian.org/debian/
+else
+  echo "INFO: Skipping debian bootstrap"
+fi
+
+sudo mount --bind /dev "$BUILD/chroot/dev"
+sudo mount --bind /run "$BUILD/chroot/run"
+
+sudo cp "$SCRIPT/setup.sh" "$BUILD/chroot/usr/local/bin"
+
+sudo chroot "$BUILD/chroot" /usr/local/bin/setup.sh
diff --git a/debian-image/reset.sh b/debian-image/reset.sh
new file mode 100755
index 0000000..53a18e6
--- /dev/null
+++ b/debian-image/reset.sh
@@ -0,0 +1,7 @@
+#!/usr/bin/env bash
+
+SCRIPT=$(dirname "$0")
+BUILD="$SCRIPT/build"
+
+sudo umount "$BUILD/chroot/"
+rm -r "$BUILD"
diff --git a/debian-image/setup.sh b/debian-image/setup.sh
new file mode 100755
index 0000000..eb715e9
--- /dev/null
+++ b/debian-image/setup.sh
@@ -0,0 +1,48 @@
+#!/bin/bash
+# ^^ not compatible on purpose, this only runs inside debian
+
+function info {
+    echo "INFO DEB:" "$@"
+}
+
+export PATH="/usr/local/bin:/usr/bin:/bin"
+export HOME=/root
+export LC_ALL=C
+
+info "Hello from debian!"
+
+info "Setting up mounts"
+
+mount none -t proc /proc
+mount none -t sysfs /sys
+mount none -t devpts /dev/pts
+
+info "Configuring the system"
+
+echo "debian-image" > /etc/hostname
+cat <<EOF > /etc/apt/sources.list
+deb http://deb.debian.org/debian/ bookworm main contrib non-free
+deb-src http://deb.debian.org/debian/ bookworm main contrib non-free
+
+deb http://deb.debian.org/debian/ bookworm-updates main contrib non-free
+deb-src http://deb.debian.org/debian/ bookworm-updates main contrib non-free
+
+deb http://deb.debian.org/debian-security bookworm-security main
+deb-src http://deb.debian.org/debian-security bookworm-security main
+EOF
+
+cat <<EOF > /etc/fstab
+# /etc/fstab: static file system information.
+#
+# Use 'blkid' to print the universally unique identifier for a
+# device; this may be used with UUID= as a more robust way to name devices
+# that works even if disks are added and removed. See fstab(5).
+#
+# <file system>         <mount point>   <type>  <options>                       <dump>  <pass>
+/dev/sda2               /               ext4    errors=remount-ro               0       1
+/dev/sda1               /boot           ext4    defaults                        0       2
+EOF
+
+apt-get update
+apt-get install -y apt-utils
+apt-get install -y systemd-sysv
diff --git a/shell.nix b/shell.nix
new file mode 100644
index 0000000..a686082
--- /dev/null
+++ b/shell.nix
@@ -0,0 +1,3 @@
+{ pkgs ? import <nixpkgs> { } }: pkgs.mkShell {
+  packages = with pkgs; [ debootstrap ];
+}