add scripts to start vm and install rpms

Add `./run_vm.sh` which starts a VM, from an image passed in as
the first argument, with an authorized SSH keypair to access the
VM. `./install_vm_rpms.sh` then adds the RPMs to the running
VM. The VM can then be accessed using the generated SSH key
id for manual testing/verification.

.gitignore

@@ -1 +1,2 @@
 build/
+vm/

README.md

@@ -79,3 +79,26 @@ To build without using a container, execute:
 ```
 make rpm
 ```
+
+## Testing in a VM
+
+This requires `libguestfs-tools-c` and `qemu-kvm` installed.
+
+`./run_vm.sh` will provision a VM image (`.qcow2` or `.raw`) passed as
+the first argument, and start up a VM which you can SSH into. After
+running `./run_vm.sh`, run `./install_vm_rpms.sh` to install the last
+built RPMs from `./build_rpm.sh` in the VM. You can then SSH into the
+machine using the details that `./install_vm_rpms.sh` outputs to the
+terminal.
+
+```
+./clean_rpm.sh && ./build_rpm.sh
+./run_vm.sh path/to/image.qcow2
+./install_vm_rpms.sh
+```
+
+To iterate while the VM is running, after committing changes locally:
+
+```
+./clean_rpm.sh && ./build_rpm.sh && ./install_vm_rpms.sh
+```

install_vm_rpms.sh

@@ -0,0 +1,29 @@
+#!/usr/bin/bash
+
+set -xeuo pipefail
+
+pkg=console-login-helper-messages
+vmdir=./vm
+sshkey_path="$vmdir/id_rsa"
+ssh_port=2226
+
+rpms_paths=$(ls ./build/$pkg/rpms/noarch/${pkg}-*.noarch.rpm | tr '\n' ' ')
+ssh_opts="-o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null"
+
+# Remove old RPMs in VM image.
+ssh $ssh_opts -i $sshkey_path -p $ssh_port root@localhost "pkgs=\$(rpm -qa | grep ${pkg}) ; if [ -n \"\$pkgs\" ]; then echo \"\$pkgs\" | xargs rpm -e; fi"
+ssh $ssh_opts -i $sshkey_path -p $ssh_port root@localhost "rm -f /root/${pkg}-*.noarch.rpm"
+
+# Copy new RPMs to VM image.
+scp $ssh_opts -i $sshkey_path -P $ssh_port $rpms_paths root@localhost:/root
+
+# Install new RPMs in VM.
+ssh $ssh_opts -i $sshkey_path -p $ssh_port root@localhost "rpm -i /root/${pkg}-*.noarch.rpm"
+
+# Enable applicable units, and reboot the VM so the services start as
+# if installed already.
+ssh $ssh_opts -i $sshkey_path -p $ssh_port root@localhost "systemctl enable console-login-helper-messages-issuegen.path"
+ssh $ssh_opts -i $sshkey_path -p $ssh_port root@localhost "systemctl enable console-login-helper-messages-motdgen.path"
+ssh $ssh_opts -i $sshkey_path -p $ssh_port root@localhost "systemctl reboot"
+
+echo SSH into the VM with: ssh -i $sshkey_path -p $ssh_port root@localhost

run_vm.sh

@@ -0,0 +1,30 @@
+#!/usr/bin/bash
+
+set -xeuo pipefail
+
+vmdir=./vm
+ssh_port=2226
+mkdir -p $vmdir
+
+image_path="$1"
+
+sshkey_path="$vmdir/id_rsa"
+ssh-keygen -t rsa -f "$sshkey_path" -q -N ""
+ssh_pubkey=$(cat "${sshkey_path}.pub")
+
+guestfish --rw -i -a "$image_path" <<EOF
+mkdir-p /root/.ssh/
+chmod 0700 /root/.ssh/
+copy-in "$sshkey_path" "${sshkey_path}.pub" /root/.ssh/
+write /root/.ssh/authorized_keys "${ssh_pubkey}"
+chmod 0600 /root/.ssh/authorized_keys
+chmod 0600 /root/.ssh/id_rsa
+chmod 0644 /root/.ssh/id_rsa.pub
+write /etc/ssh/sshd_config.d/99-enable-root-login "PermitRootLogin without-password\n"
+write /etc/ssh/sshd_config.d/99-enable-pubkey "PubkeyAuthentication yes\n"
+selinux-relabel /etc/selinux/targeted/contexts/files/file_contexts /root/.ssh
+EOF
+
+qemu-kvm -m 2048 -cpu host -nographic -snapshot \
+	-drive if=virtio,file="${image_path}" \
+	-nic user,model=virtio,hostfwd=tcp::${ssh_port}-:22