add cloud-image support

Signed-off-by: Christian Rebischke <chris@nullday.de>

cloud.json

+{
+    "variables": {
+        "iso_url": "https://mirror.pkgbuild.com/iso/latest/archlinux-2019.10.01-x86_64.iso",
+        "iso_checksum_url": "https://mirror.pkgbuild.com/iso/latest/sha1sums.txt",
+        "iso_checksum_type": "sha1",
+        "disk_size": "20480",
+        "memory": "1024",
+        "cpus": "2",
+        "headless": "true",
+        "write_zeroes": "",
+        "boot_wait": "60s"
+    },
+    "builders": [
+        {
+            "type": "qemu",
+            "boot_wait": "{{user `boot_wait`}}",
+            "http_directory": "http",
+            "disk_size": "{{user `disk_size`}}",
+            "iso_checksum_url": "{{user `iso_checksum_url`}}",
+            "iso_checksum_type": "{{user `iso_checksum_type`}}",
+            "iso_url": "{{user `iso_url`}}",
+            "ssh_username": "arch",
+            "ssh_password": "arch",
+            "ssh_port": 22,
+            "ssh_wait_timeout": "10000s",
+            "shutdown_command": "sudo systemctl poweroff",
+            "headless": "{{user `headless`}}",
+            "qemuargs": [
+                [
+                    "-m",
+                    "{{user `memory`}}"
+                ],
+                [
+                    "-smp",
+                    "{{user `cpus`}}"
+                ]
+            ],
+            "boot_command": [
+                "<enter><wait10><wait10><wait10><wait10><wait10><enter><enter>",
+                "curl -O 'http://{{.HTTPIP}}:{{.HTTPPort}}/install{,-chroot}.sh'<enter><wait>",
+                "bash install.sh < install-cloud.sh && systemctl reboot<enter>"
+            ]
+        }
+    ],
+    "provisioners": [
+        {
+            "type": "shell",
+            "scripts": [
+                "provision/postinstall.sh",
+                "provision/qemu.sh",
+		"provision/cloud-init.sh",
+                "provision/cleanup.sh"
+            ],
+            "execute_command": "echo 'arch'|sudo -S sh '{{.Path}}'"
+        },
+        {
+            "type": "shell",
+            "scripts": [
+                "provision/write_zeroes.sh"
+            ],
+            "execute_command": "if [ ! -z \"{{user `write_zeroes`}}\" ]; then echo 'arch'|sudo -S sh '{{.Path}}'; fi"
+        }
+    ],
+    "post-processors": [
+        [
+            {
+                "type": "checksum",
+		"checksum_types": [
+			"sha256"
+		],
+                "output": "Arch-Linux-cloudimg-amd64-{{isotime \"2006-01-02\"}}.img"
+            },
+	    {
+		"type": "shell-local",
+		"inline": [
+			"gpg --sign --detach-sign Arch-Linux-cloudimg-amd64-{{isotime \"2006-01-02\"}}.img"
+		]
+	    }
+	]
+    ]
+}

http/install-cloud.sh

+#!/bin/bash
+
+set -e
+set -x
+
+ln -sf /usr/share/zoneinfo/UTC /etc/localtime
+sed -i -e 's/^#\(en_US.UTF-8\)/\1/' /etc/locale.gen
+locale-gen
+echo 'LANG=en_US.UTF-8' >/etc/locale.conf
+
+# setting arch user credentials
+echo -e 'arch\narch' | passwd
+useradd -m -U arch
+echo -e 'arch\narch' | passwd arch
+
+# setting automatic authentication for any action requiring admin rights via Polkit
+cat <<EOF >/etc/polkit-1/rules.d/49-nopasswd_global.rules
+polkit.addRule(function(action, subject) {
+    if (subject.isInGroup("arch")) {
+        return polkit.Result.YES;
+    }
+});
+EOF
+
+# setting sudo for arch user
+cat <<EOF >/etc/sudoers.d/arch
+Defaults:arch !requiretty
+arch ALL=(ALL) NOPASSWD: ALL
+EOF
+chmod 440 /etc/sudoers.d/arch
+
+# setup unpredictable kernel names
+ln -s /dev/null /etc/systemd/network/99-default.link
+
+# setup network
+cat <<EOF >/etc/systemd/network/eth0.network
+[Match]
+Name=eth0
+
+[Network]
+DHCP=ipv4
+EOF
+
+# Setup pacman-init.service for clean pacman keyring initialization
+cat <<EOF >/etc/systemd/system/pacman-init.service
+[Unit]
+Description=Initializes Pacman keyring
+Wants=haveged.service
+After=haveged.service
+Before=sshd.service
+ConditionFirstBoot=yes
+
+[Service]
+Type=oneshot
+RemainAfterExit=yes
+ExecStart=/usr/bin/pacman-key --init
+ExecStart=/usr/bin/pacman-key --populate archlinux
+
+[Install]
+WantedBy=multi-user.target
+EOF
+
+# enabling important services
+systemctl daemon-reload
+systemctl enable sshd
+systemctl enable haveged
+systemctl enable systemd-networkd
+systemctl enable systemd-resolved
+systemctl enable pacman-init.service
+
+if [ -b "/dev/sda" ]; then
+  grub-install /dev/sda
+elif [ -b "/dev/vda" ]; then
+  grub-install /dev/vda
+fi
+sed -i -e 's/^GRUB_TIMEOUT=.*$/GRUB_TIMEOUT=1/' /etc/default/grub
+grub-mkconfig -o /boot/grub/grub.cfg

provision/cloud-init.sh

+#!/bin/bash
+
+set -e
+set -x
+
+sudo pacman -S --noconfirm cloud-init
+sudo systemctl enable cloud-init-local.service
+sudo systemctl enable cloud-init.service
+sudo systemctl enable cloud-config.service
+sudo systemctl enable cloud-final.service