Make challenge image

challenge/init

@@ -0,0 +1,65 @@
+#!/bin/sh
+
+mount -t proc proc /proc
+mount -t sysfs sysfs /sys
+
+/bin/busybox --install -s
+
+mdev -s
+
+modprobe snd-pcsp
+
+# /proc/cmdline parser (from Gentoo Wiki)
+cmdline() {
+    local value
+    value=" $(cat /proc/cmdline) "
+    value="${value##* $1=}"
+    value="${value%% *}"
+    [ "$value" != "" ] && echo "$value"
+}
+
+# Get some command line options
+USER_LOGIN=$(cmdline adlin.login)
+USER_PKEY=$(cmdline adlin.key)
+
+# Define hostname
+hostname adlin-${USER_LOGIN}
+
+# Launch some TTYs
+for i in `seq 2 4`
+do
+    while true
+    do
+	/usr/bin/setsid /sbin/agetty -l /sbin/fakelogin 38400 "tty${i}" linux
+    done &
+done
+
+# Hide us!
+/bin/rm -f /init /linuxrc
+
+# Randomize time at boot
+/bin/date -s 197001010101 > /dev/null
+/sbin/sysctl -w net.ipv4.ip_default_ttl=4 > /dev/null
+
+# Launch some daemons
+/usr/bin/setsid /usr/sbin/crond > /dev/null &
+
+# Launch requested init
+if grep init= /proc/cmdline > /dev/null 2> /dev/null
+then
+    INIT=$(cmdline init)
+    [ -z "${INIT}" ]
+
+    while true
+    do
+	sleep $((10 + $RANDOM % 49))
+	beep -f 1000 -r 2 -n -r 5 -l 10 --new
+    done &
+
+    exec /usr/bin/setsid sh -c "exec '${INIT}' </dev/tty1 >/dev/tty1 2>&1"
+else
+    while true
+    do
+	/usr/bin/setsid /sbin/agetty -l /sbin/fakelogin 38400 tty1 linux
+    done
+fi