Install guest additions, enable passwordless sudo for vagrant user, set root password to 'vagrant', clean/minimize the resulting image

packer.json

@@ -9,6 +9,28 @@
         "install -m0700 -o {{user `user`}} -g {{user `user`}} -d /home/{{user `user`}}/.ssh",
         "curl -SsL https://raw.githubusercontent.com/mitchellh/vagrant/master/keys/vagrant.pub -o /home/{{user `user`}}/.ssh/authorized_keys"
       ]
+    },
+    { "type": "shell",
+      "execute_command": "{{ .Vars }} sudo -E -S sh '{{ .Path }}'",
+      "inline": [
+        "mount -o loop ${HOME}/VBoxGuestAdditions.iso /mnt",
+        "/mnt/VBoxLinuxAdditions.run install",
+        "umount /mnt",
+        "rm ${HOME}/VBoxGuestAdditions.iso"
+      ]
+    },
+    {
+      "type": "ansible",
+      "playbook_file": "ansible/playbook.yml"
+    },
+    { "type": "shell",
+      "execute_command": "{{ .Vars }} sudo -E -S sh '{{ .Path }}'",
+      "script": "scripts/clean.sh"
+    },
+    {
+      "type": "shell",
+      "execute_command": "{{ .Vars }} sudo -E -S sh '{{ .Path }}'",
+      "script": "scripts/minimize.sh"
     }
   ],
   "builders": [

preseeds/preseed.cfg

@@ -40,5 +40,7 @@ d-i passwd/user-password password vagrant
 d-i passwd/user-password-again password vagrant
 d-i user-setup/allow-password-weak boolean true
 d-i user-setup/encrypt-home boolean false
-d-i passwd/user-default-groups vagrant sudo
 d-i passwd/user-uid string 900
+d-i preseed/late_command string \
+    echo 'vagrant ALL=(ALL) NOPASSWD: ALL' > /target/etc/sudoers.d/vagrant ; \
+    in-target chmod 440 /etc/sudoers.d/vagrant ;

scripts/clean.sh

@@ -0,0 +1,37 @@
+#!/bin/sh -eux
+
+# Delete all Linux headers
+dpkg --list \
+  | awk '{ print $2 }' \
+  | grep 'linux-headers' \
+  | xargs apt-get -y purge;
+
+# Remove specific Linux kernels, such as linux-image-3.11.0-15 but
+# keeps the current kernel and does not touch the virtual packages,
+# e.g. 'linux-image-amd64', etc.
+dpkg --list \
+    | awk '{ print $2 }' \
+    | grep 'linux-image-[234].*' \
+    | grep -v `uname -r` \
+    | xargs apt-get -y purge;
+
+# Delete Linux source
+dpkg --list \
+    | awk '{ print $2 }' \
+    | grep linux-source \
+    | xargs apt-get -y purge;
+
+# Delete X11 libraries
+apt-get -y purge libx11-data xauth libxmuu1 libxcb1 libx11-6 libxext6;
+
+# Delete obsolete networking
+apt-get -y purge ppp pppconfig pppoeconf;
+
+# Delete oddities
+apt-get -y purge popularity-contest;
+
+apt-get -y autoremove;
+apt-get -y clean;
+
+# delete any logs that have built up during the install
+find /var/log/ -name *.log -exec rm -f {} \;

scripts/minimize.sh

@@ -0,0 +1,36 @@
+#!/bin/sh -eux
+
+case "$PACKER_BUILDER_TYPE" in
+  qemu) exit 0 ;;
+esac
+
+# Whiteout root
+count=$(df --sync -kP / | tail -n1  | awk -F ' ' '{print $4}')
+count=$(($count-1))
+dd if=/dev/zero of=/tmp/whitespace bs=1M count=$count || echo "dd exit code $? is suppressed";
+rm /tmp/whitespace
+
+# Whiteout /boot
+count=$(df --sync -kP /boot | tail -n1 | awk -F ' ' '{print $4}')
+count=$(($count-1))
+dd if=/dev/zero of=/boot/whitespace bs=1M count=$count || echo "dd exit code $? is suppressed";
+rm /boot/whitespace
+
+set +e
+swapuuid="`/sbin/blkid -o value -l -s UUID -t TYPE=swap`";
+case "$?" in
+    2|0) ;;
+    *) exit 1 ;;
+esac
+set -e
+
+if [ "x${swapuuid}" != "x" ]; then
+    # Whiteout the swap partition to reduce box size
+    # Swap is disabled till reboot
+    swappart="`readlink -f /dev/disk/by-uuid/$swapuuid`";
+    /sbin/swapoff "$swappart";
+    dd if=/dev/zero of="$swappart" bs=1M || echo "dd exit code $? is suppressed";
+    /sbin/mkswap -U "$swapuuid" "$swappart";
+fi
+
+sync;