Release Smart sudo script


dimag0g

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Smart Sudo is a new tool I'm working on. It helps you to configure your system so actions usually requiring a password entry could be executed without entering it.

I have tested it quite extensively, but before you try it, you must know how to recover from broken sudo config. Basically, if you haven't set your root password and have no clear idea about sudo config files, you might have to reflash your pandora in order to recover. You've been warned.

Now, a couple of examples:

Wakeup alarm:
- Download Wakeup alarm PND from the repo and run it
- Note that a password is needed to program the timer
- Run Smart sudo, and install "echosu" on your system
  (echosu script enables passwordless hardware access)
- Rerun Wakeup Alarm. Now it should work without password

Swap files:
- Download Swap files PND from the repo and run it
- Note that a password is needed to enable/disable swap
  (commands "swapon" and "swapoff" are concerned)
- Run Smart sudo and add "swapon" and "swapoff" to sudoers
- Now Swap tools could run without password. However,
  it doesn't know you added "swapon" and "swapoff" to
  sudoers, so it keeps asking for a password anyway.
- Run Smart sudo and install smart gksudo script
  (it checks if password is really needed before asking)
- Rerun Swap tools. Now it should work without password

Upgrade Pandora OS:

- go to main menu -> System -> Upgrade pandora OS

-  note that a password is needed to run upgrade script

- Run Smart Sudo and add "opkg" to sudoers

- make sure smart gksudo script is installed

 (same reason as for Swap tools)

- Rerun Upgrade script. Now it should work without password
 
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nice... (still concerned about security though...)

This does not throw a warning:

./echosu 25 "/sys/class/\\.\\.\/\\.\\./tmp/aaa&&rm -rf /"
 

http://alvinalexander.com/blog/post/linux-unix/how-remove-non-printable-ascii-characters-file-unix

In our case, the allowed characters are more stringent, not allowing space, ampersand, dotcomma, etc...

so to stop bobby tables. \; type of code...

Please also check $1 -gt 0 or at least numeric...

I've created a C solution (but am also not so confident it works without glitches). Will attach soon.
 
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Use CodeBlocks to compile with it's command line:

make op_wakealarm

(there is a compiled version in the zip)

instead of commandline sudo, use the GUI version gksudo

sudo chown root:users op_wakealarm
sudo chmod 4750 op_wakealarm

This does not need sudo:
cat /sys/class/rtc/rtc0/wakealarm

This does:
./op_wakealarm `date '+%s' -d '+ 3 minutes'`

ps: Because we use atoi in the code, it gets untainted/sanitized automatically. so the potato function is not required, but it still deters :)

OP.zip
 

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Use CodeBlocks to compile with it's command line:

make op_wakealarm

(there is a compiled version in the zip)

instead of commandline sudo, use the GUI version gksudo

sudo chown root:users op_wakealarm


sudo chmod 4750 op_wakealarm

This does not need sudo:


cat /sys/class/rtc/rtc0/wakealarm

This does:


./op_wakealarm `date '+%s' -d '+ 3 minutes'`


ps: Because we use atoi in the code, it gets untainted/sanitized automatically. so the potato function is not required, but it still deters :)
Please make a PND of it. Thanks.
 
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We are actually hoping that it would be incorporated in Alarm Clock. But that is not required.

The thing is, to get that working we need 3 things:

* modify Alarm Clock.

* modify /usr/pandora/scripts/op_power.sh

* Package the result in a new version of smartsudo

So Alarm Clock has its settings in /mnt/utmp/alarmclock/alarm-clock/alarms.conf

We assume that when the alarm clock is not running, this binding to the ./appdata/ does not exist, and wakeup is not required.

During a software or hardware low power mode call (either using the GUI or the slide) the script op_power.sh gets called. always afaik.

We can just make a PND that does a modification in this script. It test for the existance of the alarms.conf

If it is there, I can run a grep DateTime on that file and get the youngest date, substract like, 5 seconds, and use op_wakealarm to let it wake.

During each pandora wake up, we again test if the alarm is set, if so, set it to zero (just in case we wake the pandora up manually)

dimag0g & Zero3K, do you agree on this method?

estimated time of programming: Longer than it took to post this (including looking up the references on the internet)

-------

Now AlarmClock is written in C with GTK bindings. So Ill have to ask Sebt3 where he got his sources from.

Debian actually uses 1.2.5 and I can find the sources for that: https://launchpad.net/ubuntu/trusty/+source/alarm-clock

But We use the 1.4.x version and that has the following bug fixed:

2010-05-30  * src/alarm_thread.c: fixed missed alarms feature

This is to change the toolbutton1 label in alarm-clock.ui and remove the include directory from the PND (hey, that can be done without recompiling, just repackaging)
 
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I don't care about using it with the Alarm Clock program. I just like not needing to input my password to do upgrades, etc.
 
nice... (still concerned about security though...)
You should be :) there is no way this PND goes to the repo in its current state. There's Bobby Tables issue like you said, but there's also echo 9000 > /sys/class/power_supply/mains/charge_current. Or there could be a malware which activates wifi and switches off the led, communicating without the user knowing. And those are much harder to fix.
 
I don't care about using it with the Alarm Clock program. I just like not needing to input my password to do upgrades, etc.
Maybe entering the password for firmware upgrades isn't a bad idea after all. It's little trouble, considering you do that maybe once a month. But if you really want to do it, adding opkg to sudoers might help.

Anyhow, I have discovered that many existing PNDs which need root access usually don't execute just critical parts with sudo, but rather rather do something like "sudo ./runscript.sh", and the script does all the dirty work inside. If you want these to run without password, you'd have to give up any protection altogether. So, if you have any particular applications in mind, I suggest you to approach their authors and discuss how those apps could cope with sudo better.
 
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I don't care about using it with the Alarm Clock program. I just like not needing to input my password to do upgrades, etc.
Ah, is that all... ok, first, open a terminal and type:


sudo visudo

This starts VI. Make sure you edit at the end of the file ( :$ enter )

Then open the edit mode with o and type in:


userid ALL=NOPASSWD: ALL

Press Escape then :wq  (write quit)

Now, run to test:

gksudo /usr/pandora/scripts/op_power.sh

If your machine sleeps, great it is working.

--------------------

Second topic: Wake up 10 seconds before the first alarmclock wakeup call.

Replace the op_power.sh in /usr/pandora/scripts

This will monitor if 1. alarmclock is running, then it will "activate"

One problem I see is that alarmclock abends with a Segmentation fault because the software is unstable (does also happen with the older version on Debian itself... sigh...):

=======================================================================================


PND : /media/klomp/pandora/menu/alarmclock.pnd


PND_FSTYPE : Squashfs


APPDATADIR : /media/klomp/pandora/appdata/alarmclock


APPDD_FSTYPE : ext3


PND_CPUSPEED :


EXENAME : scripts/alarm-clock.sh


ARGUMENTS :


=======================================================================================


[ START ]--- Mount the PND ----------


Mounting : mount -t squashfs -o ro "/dev/loop1" "/mnt/utmp/alarmclock"


Mounting the Union FS : mount -t aufs -o exec,dirs="/media/klomp/pandora/appdata/alarmclock=rw+nolwh":"/mnt/pnd/alarmclock=rr" none "/mnt/utmp/alarmclock"


[sUCCESS]--- Mount the PND ----------


[ START ]--- Starting the application ( scripts/alarm-clock.sh ) ----------

(alarm-clock:2541): Gtk-CRITICAL **: gtk_list_store_set_valist: assertion `VALID_ITER (iter, list_store)' failed


/usr/pandora/scripts/pnd_run.sh: line 522: 2541 Segmentation fault "./$EXENAME" $ARGUMENTS "$@"


[ FAILED]--- Starting the application ( scripts/alarm-clock.sh ) ----------


[ START ]--- Restoring the frame buffer status ----------


[sUCCESS]--- Restoring the frame buffer status ----------


[ START ]--- uMount the PND ----------


[ START ]--- Waiting the Union to be available ----------


[sUCCESS]--- Waiting the Union to be available ----------


auplink:plink.c:223: AUFS_CTL_PLINK_MAINT: Inappropriate ioctl for device


rmdir: failed to remove `/mnt/utmp/alarmclock': Device or resource busy


[ START ]--- Waiting the PND mount dir to be free ----------


[sUCCESS]--- Waiting the PND mount dir to be free ----------


cleanup done


[sUCCESS]--- uMount the PND ----------


=======================================================================================


Return code is : 3

Reproducing the error:

Create a schedule weekly, create a schedule for tomorrow morning. Then:

Create an entry 1 minute in the future. Wait for the ring. Then do this again. The application abends just one second after ringing.

op_power.sh.zip
 

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one other thing: you can also skip one of the processes from going into sleepmode by not doing a kill -STOP, If we look at orageclock, it consumes 0.3 CPU, alarmclock uses more, but much less if minimized (never use the X to close the window, always use the trayicon, this way, you can unminimize properly).
 
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