hook/zfs: implement zfs+native encryption support

Closes: #24

hook/zfs/zfs

@@ -0,0 +1,18 @@
+# vim: set ft=sh:
+# shellcheck shell=sh
+#
+# https://shellcheck.net/wiki/SC2154
+# shellcheck disable=2154
+
+[ "$zfs_key" ] && {
+    copy_file "${zfs_key#*=}" /root/zfs_key 0400
+
+    sed "s|${zfs_key#*=}|/root/zfs_key|" \
+        "${tmpdir}/etc/tinyramfs/config" > "${tmpdir}/_"
+
+    mv "${tmpdir}/_" "${tmpdir}/etc/tinyramfs/config"
+}
+
+copy_kmod zfs
+copy_exec zfs
+copy_exec zpool

hook/zfs/zfs.init

@@ -0,0 +1,16 @@
+# vim: set ft=sh:
+# shellcheck shell=sh
+#
+# https://shellcheck.net/wiki/SC2154
+# shellcheck disable=2154
+
+modprobe zfs 2> /dev/null
+
+resolve_device "$zfs_root"
+zpool import -Nd "$device" "${root%%/*}"
+
+if [ "$zfs_key" ]; then
+    zfs load-key -L "file://${zfs_key}" "$root"
+elif [ "$(zfs get -Ho value encryption "$root")" != off ]; then
+    zfs load-key -L prompt "$root"
+fi