#!/bin/sh

# /etc/rc for an embedded Linux system

# Copyright (C)2013-2024, Philip Munts dba Munts Technologies.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are met:
#
# * Redistributions of source code must retain the above copyright notice,
#   this list of conditions and the following disclaimer.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
# LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
# POSSIBILITY OF SUCH DAMAGE.

# Boot time options are passed via OPTIONS=0x0XXXX on the kernel command line.

# Boot time options bit definitions:

# Bit  0 -- Enable USB serial gadget with getty
# Bit  1 -- Enable USB network gadget with DHCP server
# Bit  2 -- Run crond
# Bit  3 -- Run ntpd
# Bit  4 -- Run rpcbind
# Bit  5 -- Run sshd
# Bit  6 -- Run httpd
# Bit  7 -- Enable USB serial gadget without getty
# Bit  8 -- Run autoexec.script
# Bit  9 -- Run mdnsd
# Bit 10 -- Run inetd
# Bit 11 -- Enable USB network gadget with DHCP client
# Bit 12 -- Enable USB raw HID gadget
# Bit 13 -- Enable /etc/rc debugging

# Define a function to wait for a file or device node to be created

WaitForFile()
{
  while [ ! $1 $2 ]
  do
    test $((OPTIONS & 0x2000)) -ne 0 && echo "DEBUG: Wait for $2"
    usleep 100000
  done
}

# Define a function to wait for a network interface to be created

WaitForNetIF()
{
  grep -q ${1}: /proc/net/dev

  while [ $? -ne 0 ]
  do
    test $((OPTIONS & 0x2000)) -ne 0 && echo "DEBUG: Wait for $1"
    usleep 100000

    grep -q ${1}: /proc/net/dev
  done
}

# Here we go

echo "Starting MuntsOS Embedded Linux"

# Configure path for this script

export PATH=/bin:/sbin:/usr/bin:/usr/sbin:/usr/local/bin:/usr/local/sbin

# Fix root file system permissions

chmod 755 /

# Mount all file systems

mount -a
WaitForFile -d /dev/shm
WaitForFile -d /dev/pts
WaitForFile -d /proc
WaitForFile -d /sys
WaitForFile -d /sys/kernel/config
WaitForFile -d /sys/kernel/debug

touch /tmp/booting.flag

# Create initial devices

mdev -s

# Start hotplug helper

mdev -d

# Create a symbolic link to the boot partition

if [ -n "${BOOTPART}" ]; then
  WaitForFile -b /dev/${BOOTPART}
  ln -s ${BOOTPART} /dev/bootdisk
  unset BOOTPART
fi

# Set CPU frequency governor

if [ -f /etc/scaling_governor ]; then
  GUV=/sys/devices/system/cpu/cpufreq/policy0/scaling_governor
  WaitForFile -f ${GUV}
  cat /etc/scaling_governor >${GUV}
  unset GUV
fi

# Initialize user LED

WaitForFile -f @@USERLED@@/trigger
echo none >    @@USERLED@@/trigger
WaitForFile -f @@USERLED@@/brightness
echo 0 >       @@USERLED@@/brightness
chown root.led @@USERLED@@/brightness
chmod 660      @@USERLED@@/brightness
ln -s          @@USERLED@@/brightness /dev/userled

# Set platform identification environment variables

export BOARDBASE=@@BOARDBASE@@
export BOARDNAME=${BOARDNAME:-@@BOARDNAME@@}
export BOARDARCH=@@BOARDARCH@@

# Create /etc/platform

echo "OSNAME=MuntsOS"				>/etc/platform
echo "OSREVISION=@@REVISION@@"			>>/etc/platform
echo "BOARDBASE=${BOARDBASE}"			>>/etc/platform
echo "BOARDNAME=${BOARDNAME}"			>>/etc/platform
echo "BOARDARCH=${BOARDARCH}"		>>/etc/platform
echo "KERNELREPO=@@KERNELREPO@@"		>>/etc/platform
echo "KERNELBRANCH=@@KERNELBRANCH@@"		>>/etc/platform
echo "KERNELCOMMIT=@@KERNELCOMMIT@@"		>>/etc/platform
echo "OPTIONS=${OPTIONS}"			>>/etc/platform
echo "SERIALNUMBER=`serialnumber`"		>>/etc/platform
echo "TOOLCHAINBUILDER=@@TOOLCHAINBUILDER@@"	>>/etc/platform
echo "TOOLCHAINREVISION=@@TOOLCHAINREVISION@@"	>>/etc/platform

if [ -n "${SHIELDNAME}" ]; then
  echo "SHIELDNAME=${SHIELDNAME}"  >>/etc/platform
fi

chmod 444 /etc/platform

# Symlink /dev/gpiochip-rpi to proper /dev/gpiochipN for Raspberry Pi
# expansion header GPIO pins

test -x /usr/libexec/link-gpiochip && /usr/libexec/link-gpiochip

# Scan shared libraries

linklibs
ldconfig

# Configure localhost interface

ifconfig lo 127.0.0.1 netmask 255.255.255.0

# Block everything coming in

iptables -w -P INPUT DROP
iptables -w -P FORWARD DROP

# Allow unrestricted access to localhost

iptables -w -I INPUT -i lo -j ACCEPT

# Allow established or related

iptables -w -A INPUT -m conntrack --ctstate ESTABLISHED,RELATED -j ACCEPT

# Allow ping

iptables -w -A INPUT -p icmp --icmp-type 8 -m conntrack --ctstate NEW -j ACCEPT

# Allow mdns

if [ $((OPTIONS & 0x200)) -ne 0 ]; then
  iptables -w -A INPUT -p udp -m pkttype --pkt-type multicast -d 224.0.0.251 --dport 5353 -j ACCEPT
fi

# Allow everything going out

iptables -w -P OUTPUT ACCEPT

# Mount /boot and look for device tree overlays, tarballs and packages

mount -o ro /boot >/dev/null 2>&1
if [ $? -eq 0 ]; then

# Install the device tree overlays requested in /boot/overlays.txt

  /usr/libexec/install-overlays

# Extract tarballs, if any

  for t in /boot/tarballs/*gz ; do
    if [ -f $t ]; then
      tar xzf $t --directory=/
    fi
  done

# Configure initial hostname if /etc/hostname came from a tarball

  test -f /etc/hostname && hostname -F /etc/hostname

# Configure GPIO pin modes

  if [ -x /sbin/config-pin -a -f /etc/pinmux.conf ]; then
    config-pin -c /etc/pinmux.conf
  fi

  if [ -x /sbin/pinctrl -a -f /etc/pinmux.conf ]; then
    awk '{ sub("[ \t]*[#].*$",""); gsub("[ \t]+", " "); if ($0 != "") printf("pinctrl set %s\n", $0); }' /etc/pinmux.conf | sh
  fi

# Install packages, if any

  for p in /boot/packages/*.deb ; do
    if [ -f $p ]; then
      dpkg -i $p >/dev/null
    fi
  done

  for p in /boot/packages/*.rpm ; do
    if [ -f $p ]; then
      rpm -i $p >/dev/null
    fi
  done

  for p in /boot/packages/*.nupkg ; do
    if [ -f $p ]; then
      nupkg $p
    fi
  done

# Pick up any new libraries

  linklibs
  ldconfig

# Pick up any new environment variables

  if [ -f /etc/environment ]; then
    for e in `cat /etc/environment` ; do
      export $e
    done
  fi

  if [ -f /var/run/environment ]; then
    for e in `cat /var/run/environment` ; do
      export $e
    done
  fi

  umount /boot
fi

# Configure initial hostname

if [ -f /etc/hostname ]; then
  hostname -F /etc/hostname
else
  hostname `uname -r | awk -F '-' '{ printf("%s-%s\n", $2, $3); }'`
fi

# Load kernel modules specified in /etc/modules

if [ -f /etc/modules ]; then
  sed -e 's/#.*$//g' -e 's/^\s*//g' -e 's/\s*$//g' -e '/^$/d' -e 's/^/modprobe /' /etc/modules | sh
fi

# Load kernel modules for built-in wireless network interfaces

grep -q -i "BeagleBone Black Wireless" /proc/device-tree/model
if [ $? -eq 0 ]; then
  modprobe wl18xx
  modprobe wlcore_sdio
  WaitForNetIF wlan0
fi

grep -q -i "BeagleBone Green Wireless" /proc/device-tree/model
if [ $? -eq 0 ]; then
  modprobe wl18xx
  modprobe wlcore_sdio
  WaitForNetIF wlan0
fi

grep -q -i "Raspberry Pi Zero W" /proc/device-tree/model
if [ $? -eq 0 -a -f /sys/bus/sdio/devices/mmc1:0001:1/vendor ]; then
  modprobe brcmfmac
  WaitForNetIF wlan0
fi

grep -q -i "Raspberry Pi Zero 2" /proc/device-tree/model
if [ $? -eq 0 -a -f /sys/bus/sdio/devices/mmc1:0001:1/vendor ]; then
  modprobe brcmfmac
  WaitForNetIF wlan0
fi

grep -q -i "Raspberry Pi 3 Model A" /proc/device-tree/model
if [ $? -eq 0 -a -f /sys/bus/sdio/devices/mmc1:0001:1/vendor ]; then
  modprobe brcmfmac
  WaitForNetIF wlan0
fi

grep -q -i "Raspberry Pi 3 Model B" /proc/device-tree/model
if [ $? -eq 0 -a -f /sys/bus/sdio/devices/mmc1:0001:1/vendor ]; then
  modprobe brcmfmac
  WaitForNetIF wlan0
fi

grep -q -i "Raspberry Pi 4 Model B" /proc/device-tree/model
if [ $? -eq 0 -a -f /sys/bus/sdio/devices/mmc1:0001:1/vendor ]; then
  modprobe brcmfmac
  WaitForNetIF wlan0
fi

grep -q -i "Raspberry Pi Compute Module 4" /proc/device-tree/model
if [ $? -eq 0 -a -f /sys/bus/sdio/devices/mmc1:0001:1/vendor ]; then
  modprobe brcmfmac
  WaitForNetIF wlan0
fi

grep -q -i "Raspberry Pi 5 Model B" /proc/device-tree/model
if [ $? -eq 0 -a -f /sys/bus/sdio/devices/mmc1:0001:1/vendor ]; then
  modprobe brcmfmac
  WaitForNetIF wlan0
fi

# Load USB Gadget Network module

if [ $((OPTIONS & 0x802)) -ne 0 ]; then
  if [ -f /etc/g_ether.conf ]; then
    . /etc/g_ether.conf
  fi

  modprobe g_ether dev_addr=${GETHMACADDR:-02:00:00:00:00:01} host_addr=${GETHMACADDRHOST:-02:00:00:00:00:02}
  WaitForNetIF usb0
fi

# Load USB Gadget Raw HID module

if [ $((OPTIONS & 0x1000)) -ne 0 ]; then
  if [ -f /etc/g_hid.conf ]; then
    . /etc/g_hid.conf
  fi

  modprobe g_hid idVendor=${GHIDVID:-0x16D0} idProduct=${GHIDPID:-0x0AFA} iManufacturer="${GHIDMFG:-Munts Technologies}" iProduct="${GHIDPROD:-USB HID Device}" iSerialNumber="${GHIDSERIAL:-`serialnumber`}"
  WaitForFile -c /dev/hidg0
fi

# Load USB Gadget Serial module

if [ $((OPTIONS & 0x81)) -ne 0 ]; then
  modprobe g_serial
  WaitForFile -c /dev/ttyGS0
fi

# Run getty on USB Gadget Serial interface, if requested

if [ -c /dev/ttyGS0 -a $((OPTIONS & 0x01)) -ne 0 ]; then
  runsv /usr/libexec/services/ttyGS0 &
fi

# Prod network interfaces

for E in /sys/class/net/*/uevent ; do
  test -f $E && echo add >$E
done

# Start system logger

syslogd

# Start crond

if [ $((OPTIONS & 0x04)) -ne 0 -a -d /var/spool/cron/crontabs ]; then
  crond
fi

# Start ONC/RPC endpoint mapper

if [ $((OPTIONS & 0x10)) -ne 0 ]; then
  iptables -w -A INPUT -p tcp -m conntrack --ctstate NEW --dport 111 -j ACCEPT
  iptables -w -A INPUT -p udp -m conntrack --ctstate NEW --dport 111 -j ACCEPT
  rpcbind
fi

# Start SSH server

if [ $((OPTIONS & 0x20)) -ne 0 -a -d /etc/ssh ]; then
  iptables -w -A INPUT -p tcp -m conntrack --ctstate NEW --dport 22 -j ACCEPT
  test -f /etc/ssh/ssh_host_rsa_key || ssh-keygen -q -C "`hostname`" -N "" -t rsa -b 4096 -f /etc/ssh/ssh_host_rsa_key && sysconfig --save
  /usr/sbin/sshd
fi

# Start web server

if [ $((OPTIONS & 0x40)) -ne 0 -a -f /etc/httpd.conf -a -d /www ]; then
  iptables -w -A INPUT -p tcp -m conntrack --ctstate NEW --dport 80 -j ACCEPT
  httpd -c /etc/httpd.conf -u 65534:65534 -h /www
fi

# Register dynamic IP address, if applicable

for noip2config in /usr/local/etc/noip2*.conf ; do
  if [ -f $noip2config ]; then
    noip2 -M -c $noip2config
  fi
done

# Start inetd

if [ $((OPTIONS & 0x400)) -ne 0 -a -f /etc/inetd.conf ]; then
  inetd
fi

# Run package startup scripts in /etc/rc.d; if present

for s in /etc/rc.d/* ; do
  if [ -x $s ]; then
    $s
  fi
done

# Run /etc/rc.local, if it is available

if [ -x /etc/rc.local ]; then
  /etc/rc.local
fi

# Run application software on other media

if [ $((OPTIONS & 0x100)) -ne 0 -a -x /usr/libexec/autoexec.script ]; then
  /usr/libexec/autoexec.script
fi

# Scan USB devices one last time, to pick up any newly installed kernel modules,
# configuration files, etc.

if [ -d /sys/bus/usb/devices ]; then
  lsusb | awk '{ printf("modprobe usb:v%sp%sd*dc*dsc*dp*ic*isc*ip*in*\n", toupper(substr($6, 1, 4)), toupper(substr($6, 6, 4))); }' | sh 2>&1 | grep -v 'not found'
fi

# Reload /etc/inittab, in case it has been changed

kill -HUP 1

# Turn on the user LED to indicate startup is finished.

echo 1 >/dev/userled

rm /tmp/booting.flag