4.8 KiB
wz_mini boot process
load kernel with initramfs built in
initramfs: /etc/init runs exec busybox switch_root /v3 /opt/wz_mini/etc/init.d/v3_init.sh
/opt/wz_mini/etc/init.d/v3_init.sh:
bind replace the factory busybox, which is missing a bunch of utilities, with our own fully featured version
mount /configs to check if the model of the camera is HL_PAN2. If it is, change some variables.
mount /params if it exists, to check if the model of the camera is V2. If it is, change some variable
Check if /opt/wz_mini/etc/.first_boot exists, if it does, play some audio to notify the user that the first boot init is running.
bind replace /etc/init.d/inittab with our own version that has rcS located at /opt/wz_mini/tmp/.storage/rcS
bind replace /etc/profile with out own version with added PATH variables for the shell
mount /tmp
mount /system
create the file touch /tmp/usrflag to make iCamera happy, normally created by /system/bin/factorycheck
bind replace /system/bin/factorycheck, this factory included program unmounts the binds that we do later in the script, since its a debug program, we don't need it. Replace it with a fake.
bind replace /etc/fstab with our own version which includes /opt/wz_mini/tmp as a tmpfs path
mount wz_mini's tmp directory at /opt/wz_mini/tmp
install our busybox's applets to /opt/wz_mini/tmp/.bin
create a workplace directory for wz_mini at /opt/wz_mini/tmp/.storage
copy the stock /etc/init.d/rcS to the workplace directory
modify the stock rcS, add set -x debug mode, inject the following script /opt/wz_mini/etc/init.d/wz_post.sh to run, and add a section to change PATH and LD_LIBRARY if desired
bind replace /etc/shadow to change the stock password
check to see if the swap archive is present at /opt/wz_mini/swap.gz, if it is, extract it, then mkswap it, and drop the vm caches.
check to see if the /opt/wz_mini/usr/share/terminfo directory is present, if not, extract the terminfo files for console programs
run the dropbear ssh daemon
check to see if /opt/wz_mini/wz_user.sh has debug mode enabled, if it does, skip loading /system/bin/app_init.sh and /opt/wz_mini/etc/init.d/wz_user.sh
check to see if /opt/wz_mini/wz_user.sh has webcam mode enabled, if it does, skip loading /system/bin/app_init.sh and instead load /opt/wz_mini/etc/init.d/wz_cam.sh
check to see if /opt/wz_mini/wz_user.sh has upgrade mode enabled, if it does, skip loading /system/bin/app_init.sh and instead load /opt/wz_mini/usr/bin/upgrade-run.sh
run /linuxrc to kick off the stock boot process
inittab:
our modified inittab runs from /opt/wz_mini/tmp/.storage/rcS, we have enabled set -x debug info, added /opt/wz_mini/bin and /opt/wz_mini/lib to the system PATH's, and added /opt/wz_mini/etc/init.d/wz_post.sh to run before /system/init/app_init.sh runs.
/opt/wz_mini/etc/init.d/wz_post.sh checks if wz_user.sh has the RTSP server enabled, and if it does, we copy /system/bin/iCamera to our workplace directory at /opt/wz_mini/tmp/.storage/
bind replace /system/bin/iCamera
our version of iCamera is a script which injects the libcallback.so library as LD_PRELOAD to hook the Audio and Video to the RTSP Server, calling iCamera from it's new home at /opt/wz_mini/tmp/.storage/
we then load the video loopback driver from /opt/wz_mini/lib/modules/v4l2loopback.ko
/system/bin/app_init.sh loads the stock system software
During execution of wz_user.sh, if DISABLE_FW_UPGRADE is set to false we intercept the stock firmware upgrade process. We run inotifyd at startup, to observe the /tmp/Upgrade directory.
Normally, iCamera downloads the firmware upgrade tar to /tmp/img, renames it to /tmp/Upgrade.tar, then extracts it to /tmp/Upgrade
inotifyd monitors /tmp/Upgrade for the file upgraderun.sh, this is the script responsible for flashing the firmware files to their respective partitions. Once the file appears, inotifyd calls the script /opt/wz_mini/usr/bin/watch_up.sh which will rename the file to upgraderun.old and kill the script if iCamera was fast enough to launch it before we renamed it.
watch_up.sh will then proceed to flash the main partitions directly, instead of doing what the stock script does, which is to flash the images to backup partitions, and then let the bootloader flash the main partitions upon reboot, since this process is currently broken when using the loading the kernel from the micro sd card, which we do.
Once the partitions have been flashed, we reboot the camera, and the FW upgrade is complete.