init-script

#!/bin/sh
#
# Hybris adaptation bootstrapping initramfs init script.
#
# Copyright (c) 2014 Jolla Oy
#
# This program is free software; you can redistribute it and/or modify it under
# the terms of the GNU General Public License version 2 as published by the
# Free Software Foundation.
#
# Authors:
#   - Tom Swindell <t.swindell@rubyx.co.uk>
#   - David Greaves <david@dgreaves.com>
#

# This init script runs in early boot in initrd and does a switch_root
# to the real rootfs. It can also be copied into rootfs and provide
# monitoring of the boot process there too.

# Be careful - you can't run any external commands until busybox has installed.

# General logging
set -x
exec > /init.log 2>&1
echo "Running Mer Boat Loader"

BOOTLOGO=%BOOTLOGO%
ALWAYSDEBUG=%ALWAYSDEBUG%
DATA_PARTITION=%DATA_PART%
DEFAULT_OS=%DEFAULT_OS%

set_welcome_msg(){
cat <<EOF >> /etc/issue.net
Welcome to the Mer/SailfishOS Boat loader debug init system.

Log so far is in /init.log

You may inject commands into init shell process (PID 1):

To see output of commands as they're injected:
  tail -f /init.log &
To run a command:
  echo "ls -l /" >/init-ctl/stdin

(Be careful if you experiment with exec as you need to terminate
daemons and disable busybox hotplug handling)

To allow init to continue:
  echo "continue" >/init-ctl/stdin

The init script also functions as a post-switch_root debugger too:
  cp /init /target/init-debug
(When run post-switch_root, telnet is on port 2323, not 23)

In order to work safely with the device's mmc you should
  echo "umount_stowaways" >/init-ctl/stdin

Then you can mount and modify exported mass storage on host. When done
  echo "mount_stowaways" >/init-ctl/stdin


EOF
}

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

# Default setting is rndis - add mass_storage for a debug boot
# enable using usb_setup
USB_FUNCTIONS=rndis

ANDROID_USB=/sys/class/android_usb/android0
LOCAL_IP=192.168.2.1

DONE_SWITCH=no
# Are we running in real rootfs
if [ "$0" = "/init-debug" ]; then
    DONE_SWITCH=yes
fi

# Get options from kernel command line
get_opt() {
  for param in $(cat /proc/cmdline); do
    echo "$param" | grep "^$1=*" | cut -d'=' -f2
  done
}

# Minimal mounts for initrd or pre-init debug session
do_mount_devprocsys()
{
    echo "########################## mounting devprocsys"
    mkdir /dev
    mount -t devtmpfs devtmpfs /dev
    # telnetd needs /dev/pts/ entries
    mkdir /dev/pts
    mount -t devpts devpts /dev/pts

    mkdir /proc
    mkdir /sys
    mount -t sysfs sysfs /sys
    mount -t proc proc /proc
}

do_hotplug_scan()
{
    echo /sbin/mdev > /proc/sys/kernel/hotplug
    mdev -s
    # There is no way to know when all hotplug events have been processed :(
    sleep 2
}

bootsplash() {
    if [ x$BOOTLOGO = x1 ]; then
	zcat /bootsplash.gz > /dev/fb0
    fi
}


mount_stowaways() {
    echo "########################## mounting stowaways"
    if [ ! -z $DATA_PARTITION ]; then
	mkdir /data
	mkdir /target

	mount $DATA_PARTITION /data
	mount --bind /data/.stowaways/${DEFAULT_OS} /target
	mkdir /target/data # in new fs
	mount --bind /data /target/data
    else
        echo "Failed to mount /target, device node '$DATA_PARTITION' not found!" >> /diagnosis.log
    fi
    mount
}

umount_stowaways()
    if [ ! -z $DATA_PARTITION ]; then
	umount /target/data
	umount /target
	umount /data
    fi

# Sugar for accessing usb config
write() {
  echo -n "$2" > "$1"
}

inject_loop() {
    INJ_DIR=/init-ctl
    INJ_STDIN=$INJ_DIR/stdin

    mkdir $INJ_DIR
    mkfifo $INJ_STDIN
    echo "This entire directory is for debugging init - it can safely be removed" > $INJ_DIR/README

    echo "########################## Beginning inject loop"
    while : ; do
        while read IN; do
	    if [ "$IN" = "continue" ]; then break 2;fi
            $IN
        done <$INJ_STDIN
    done
    rm -rf $INJ_DIR # Clean up if we exited nicely
    echo "########################## inject loop done"
}

# This sets up the USB with whatever USB_FUNCTIONS are set to
usb_setup() {
      write $ANDROID_USB/enable        0
      write $ANDROID_USB/functions     ""
      write $ANDROID_USB/enable        1
      usleep 500000 # 0.5 delay to attempt to remove rndis function
      write $ANDROID_USB/enable        0
      write $ANDROID_USB/idVendor      18D1
      write $ANDROID_USB/idProduct     D001
      write $ANDROID_USB/iManufacturer "Mer Boat Loader"
      write $ANDROID_USB/iProduct      "$CUSTOMPRODUCT"
      write $ANDROID_USB/iSerial       "$1"
      write $ANDROID_USB/functions     $USB_FUNCTIONS
      write $ANDROID_USB/enable        1
}
# This lets us communicate errors to host (if it needs disable/enable then that's a problem)
usb_info() {
    # make sure USB is settled
    echo "########################## usb_info: $1"
    sleep 1
    write $ANDROID_USB/iSerial       "$1"
}


run_debug_session() {
    CUSTOMPRODUCT=$1
    echo "########################## Debug session : $1"
    usb_setup "Mer Debug setting up (DONE_SWITCH=$DONE_SWITCH)"

    USB_IFACE=notfound
    /sbin/ifconfig usb0   $LOCAL_IP && USB_IFACE=usb0
    /sbin/ifconfig rndis0 $LOCAL_IP && USB_IFACE=rndis0
    # Report for the logs
    /sbin/ifconfig

    # Unable to set up USB interface? Reboot.
    if [ x$USB_IFACE = xnotfound ]; then
	usb_info "Mer Debug: ERROR: could not setup USB as usb0 or rndis0"
	dmesg
	sleep 60 # plenty long enough to check usb on host
	reboot -f
    fi

    echo "interface $USB_IFACE" >> /etc/udhcpd.conf
    # Be explicit about busybox so this works in a rootfs too
    echo "########################## starting dhcpd"
    $EXPLICIT_BUSYBOX udhcpd

    set_welcome_msg
    # Non-blocking telnetd
    echo "########################## starting telnetd"
    # We run telnetd on different ports pre/post-switch_root This
    # avoids problems with an unterminated pre-switch_root telnetd
    # hogging the port
    $EXPLICIT_BUSYBOX telnetd -p $TELNET_DEBUG_PORT -l /bin/sh

    # For some reason this does not work in rootfs
    usb_info "Mer Debug telnet on port $TELNET_DEBUG_PORT on $USB_IFACE $LOCAL_IP - also running udhcpd"

    # Some logging output
    ps -wlT
    ps -ef
    netstat -lnp
    cat /proc/mounts
    sync

    # Run command injection loop = can be exited via 'continue'
    inject_loop
}

# writes to /diagnosis.log if there's a problem
check_kernel_config() {
    echo "Checking kernel config"
    if [ ! -e /proc/config.gz ]; then
	echo "No /proc/config.gz. Enable CONFIG_IKCONFIG and CONFIG_IKCONFIG_PROC" >> /diagnosis.log
    else
	# Must be =y
	for x in CONFIG_CGROUPS CONFIG_AUTOFS4_FS CONFIG_DEVTMPFS_MOUNT CONFIG_DEVTMPFS CONFIG_UNIX CONFIG_HOTPLUG CONFIG_INOTIFY_USER CONFIG_SYSVIPC CONFIG_NET CONFIG_PROC_FS CONFIG_SIGNALFD CONFIG_SYSFS CONFIG_TMPFS_POSIX_ACL CONFIG_VT; do
		zcat /proc/config.gz | grep -E "^$x=y\$" || echo "$x=y not found in /proc/config.gz" >> /diagnosis.log
 	done
	# Must not be =y
	for x in CONFIG_ANDROID_LOW_MEMORY_KILLER CONFIG_ANDROID_PARANOID_NETWORK CONFIG_DUMMY CONFIG_SYSFS_DEPRECATED; do
		zcat /proc/config.gz | grep -E "^$x=y\$" && echo "$x=y found in /proc/config.gz, must be disabled" >> /diagnosis.log
	done
    fi
}

# Now either initrd or rootfs sequence

if [ "$DONE_SWITCH" = "no" ]; then
    EXPLICIT_BUSYBOX=""
    TELNET_DEBUG_PORT=23
    /bin/busybox --install -s
    date

    do_mount_devprocsys

    do_hotplug_scan

    # Support /dev/block/mmcXXX only in initrd phase
    ln -s . /dev/block
    ln -s /proc/mounts /etc/mtab

    check_kernel_config

    bootsplash

    mount_stowaways

    # No target debug unless we debug here too (for now)

    DBG_REASON=""
    [ -e /diagnosis.log ] && DBG_REASON="Refusing to boot. See /diagnosis.log (in initrd only)"
    [ "$(get_opt bootmode)" = "debug" ] && DBG_REASON="bootmode=debug on kernel command line"
    [ x$ALWAYSDEBUG = x1 ] && DBG_REASON="Always debug: rndis + mass_storage"
    [ -f /target/init_enter_debug ] && DBG_REASON="/init_enter_debug exists"

    if ! [ "$DBG_REASON" = "" ] ; then
	# During debug we export mmc too
	echo /dev/mmcblk0 > /sys/class/android_usb/f_mass_storage/lun0/file
	USB_FUNCTIONS=rndis,mass_storage

	run_debug_session $DBG_REASON

	# Tidy up before we switch_root (rootfs init-debug leaves these running during bootup)
	killall telnetd
	killall udhcpd

	USB_FUNCTIONS=rndis
	usb_setup "Mer Debug: done debug, disabling storage"
    fi

    # Disable mdev hotplug now - let udev handle it in main boot
    echo "" > /proc/sys/kernel/hotplug

    if [ -f "/target/init-debug" ]; then
	exec switch_root /target /init-debug &> /target/init-debug-stderrout
    else
	if [ -e "/target/sbin/init" ]; then
	    exec switch_root /target /sbin/init --log-level=debug --log-target=kmsg &> /target/init-stderrout
	fi
    fi
    run_debug_session "Failed to boot init in real rootfs"

else
    # We're in the real rootfs running as init-debug
    EXPLICIT_BUSYBOX="/bin/busybox-static"
    TELNET_DEBUG_PORT=2323

    do_mount_devprocsys

    run_debug_session "init-debug in real rootfs"

    # If we don't do this then udev will not be able to create /dev/block/*
    rm /dev/block

    # Now try to boot the real init
    exec /sbin/init --log-level=debug --log-target=kmsg &> /boot/systemd_stdouterr
    run_debug_session "init in real rootfs failed"
fi