Suggested hack - zoneinfo, syslog and cron

meijerwynand commented 3 years ago

Greetings,

I was unable to get the timestamps on my camera to display according to my timezone (I did a factory reset and did not use the eWeLink app to configure anything). I also wanted to have my cronjobs saved and not lost after each reboot.

Code stuff

Script

The code for all three these matters:

#!/bin/ash
## 
## set time, start syslog, the start crond

## start using syslog to see what is happening
SONOFF_HACK_PREFIX="/mnt/mmc/sonoff-hack"

SYSLOG_DIR="${SONOFF_HACK_PREFIX}/var/log"
SYSLOG_FILE="${SYSLOG_DIR}/syslog"

## where your crontabs are going to live
CRONDIR="${SONOFF_HACK_PREFIX}/var/spool/cron/crontabs"

## make a copy of your local zoneinfo file (generally /usr/share/zoneinfo),
## rename it and upload it to the location below
ZONEINFO_FILE="${SONOFF_HACK_PREFIX}/etc/localtime"
NTP_SERVER=192.168.13.1
## -----------------------------------------------------------------------------

##  ===== syslog stuff  =====
## use prep to use syslog
if [ ! -d "${SYSLOG_DIR}" ]; then 
  /bin/mkdir -p "${SYSLOG_DIR}"
fi

if [ ! -f "${SYSLOG_FILE}" ]; then 
  /bin/touch "${SYSLOG_FILE}"
fi

## kill any existing 
/usr/bin/killall syslogd &>/dev/null

## start syslog
/sbin/syslogd -O "${SYSLOG_FILE}" -D
## -----------------------------------------------------------------------------

##  ===== zone info stuff =====
## remove current zoneinfo details, replace with your zoneinfo details
if [[ -f "${ZONEINFO_FILE}" ]]; then
  /bin/rm /etc/localtime
  /bin/ln -s "${ZONEINFO_FILE}" /etc/
  /usr/sbin/ntpd -n -q -N -p "${NTP_SERVER}"
  hwclock --systz
fi
## -----------------------------------------------------------------------------

##  ===== cron stuff   =====
## 
if [ ! -d "${CRONDIR}" ]; then 
  /bin/mkdir -p "${CRONDIR}"
fi

## symlink 
## crond seems to ignore the -c flag, so, now it gets created and symlinked
/bin/mkdir -p /var/spool/cron/
ln -s "${CRONDIR}" /var/spool/cron/

## kill any existing 
/usr/bin/killall crond &>/dev/null

## start cron 
/usr/sbin/crond -b -S -l 8

Installing

create a new file /mnt/mmc/sonoff-hack/script/crond.sh with the contents shown above
add /mnt/mmc/sonoff-hack/script/crond.sh to the bottom of /mnt/mmc/sonoff-hack/script/system.sh as a single line

...
## Added crontab 
/mnt/mmc/sonoff-hack/script/crond.sh

Disable the ntpdate in the database file - /mnt/mtd/db/ipcsys.db (not sure if this really does anything) UPDATE "main"."t_sys_param" SET "c_param_value"=0 WHERE c_param_name = "NTPEnable" This was done via sqlitebrowser, copy the file locally, change it and then replace the running version on the camera

Notes

crontab

After various attempts it appears the crond does not honor the -c $work_path flag. For this work around a symlink is created with the actual saving of the crontabs to the /mnt/mmc/sonoff-hack/ path. Using this method also allows the crontabs to be saved to the SD card and they remain even after reboots.

syslog

By troubleshooting the initial crond issues, syslogd as later added to aid in understanding the strange behavior of crond (not honoring -c). It turned out to actually be a welcomed addition and decided to keep it. This is also save to the SD card which can serve as "off-line" logs.

zoneinfo

I ended up finding a copy of my zoneinfo on my local pc, so I uploaded it. During boot I remove the default /etc/localtime (Hong Kong) and do another symlink to the copy of my zoneinfo file. Followed by a timesync via ntpd and updating the hwclock to the (new) system zoneinfo.

Now once I have booted the device and logged in, my time is correct

[root@GK]# date
Fri Nov 27 16:03:45 SAST 2020

*nix paths

Here it is attempted to conform to the standard var/ etc/ paths. Similar to a *nix environment where stuff generally is found, it is now only prefixed with the SONOFF_HACK path,

crons -> ${SONOFF_HACK_PREFIX}/var/spool/cron/crontabs
syslog -> ${SONOFF_HACK_PREFIX}/var/log/syslog
localtime -> ${SONOFF_HACK_PREFIX}/etc/localtime

Conclusion

These changes seem to keep after reboots and helps with fiddling with the device. I trust someone will find this useful or even better some of these ideas make it into the project.

roleoroleo commented 3 years ago

About timezone, I already implemented (but not committed) an option to change timezone directly inside sqlite db. In this manner it's compatible with the app.

I will try to integrate cron and syslog in the hack.

Thank you for your code.

meijerwynand commented 3 years ago

Closing

roleoroleo commented 3 years ago

Syslog is missing, I will check if I can integrate it.

roleoroleo / sonoff-hack