Author Topic: how can a user change a forgotten username and/or password ?  (Read 2008 times)

secarica

  • Full Member
  • ***
  • Posts: 20
    • View Profile
how can a user change a forgotten username and/or password ?
« on: August 19, 2012, 05:32:39 AM »
Suppose I build a device based on SBC65EC, where the end user will change the default username or password and then forget it. How can the user force a password change or reset ?

Resetting the board does not seem to reset the username or password. Command ?la=new_string will require authentication with the old username and password, so this must be known. The serial interface does not offer this option either.

I know how to change directly the EEPROM string data with my PICKit 2 adapter, but this is not an option for an end user.

Any solution for this ?

Cristi

gr

  • Hero Member
  • *****
  • Posts: 169
    • View Profile
Re: how can a user change a forgotten username and/or password ?
« Reply #1 on: September 10, 2012, 01:09:49 PM »
I'm just guessing here - but does "safemode" temporarily return the password to admin/pw?  You have to move a jumper to get safemode.

secarica

  • Full Member
  • ***
  • Posts: 20
    • View Profile
Re: how can a user change a forgotten username and/or password ?
« Reply #2 on: May 12, 2016, 01:07:10 AM »
Still an open question: I get now another few brand new SBC65EC's and tried to simulate how would the end user recover, set or reset a forgotten password: I could not found any method for him! (except with a PICKit adapter as stated above, but that is not a "field" solution)

The safe mode could have been a solution, but it simply does not work (at all). There are several postings here about failure to connect in safe mode (for example this one) and the same thing occurs here: no response from the SBC board in safe mode. I tried to connect either via router or directly (either based on the Auto-MDI/X feature of the PC interface or via cross cable) / with one of the three default documented addresses / via web browser or via netloader application (either the 107 version with embedded JRE on an XP machine or the separate 106 version with 32bit JRE installed on a Vista 64bit machine) / by changing and later reverted the default address to 10.1.0.1 (as when someone cannot access the standard web pages to configure this) / by enabling or disabling DHCP via serial interface (again, as when someone cannot access the standard web pages to configure this).

Is there a bug in the safe mode portion of the bootloader ?

Edit: I also observed a strange thing by scanning the local addresses aggressively with a IP scanner application, the LED stops blinking fast and returns to normal blink mode and the board seems to return to normal operation (still with the jumper in safe mode position and without touching anything on board); I did't extend the tests here because I cannot imagine a practical use for this. I also observed that the IP scanning found two valid addresses (for a given class), i.e. the default 10.1.0.1 and the one I set manually before like 10.1.0.2, only that one of the two were marked as inactive or something.

Cristi
« Last Edit: May 12, 2016, 10:56:27 PM by secarica »

gr

  • Hero Member
  • *****
  • Posts: 169
    • View Profile
Re: how can a user change a forgotten username and/or password ?
« Reply #3 on: May 12, 2016, 07:17:56 AM »
It worked for me.  Trouble is most likely with your computer not the board.  For one thing you probably have to understand a few details about tcp/ip - this is probably the main thing actually.

Every local network setup is different but most home routers have you on 10.0.0.1, or 192.168.1.1 or similar because 192.168.*.* is reserved for this and also 10.*.*.*.

But typically the router is setup for only 255 allowed addresses for example 10.1.1.1 through 10.1.1.255.  And typically the router is at the ".1" address (e.g. 192.168.1.1).  Any addresses outside this range are TOLD TO GO THROUGH THE ROUTER!

That is the root of the problem.  But those addresses don't exist out on the internet - they are right there on your local network.  So there are several ways to fix this.  One way is to buy a $20 ethernet hub - a dumb one.  A very dumb one.  that doesn't know about routing.  Then get your computer OFF THE INTERNET (disconnect it) and connect it and your modtronix to the hub and setup your tcp/ip address manually to be one off from the expected for example 10.1.0.2 so you can connect to 10.1.0.1.  Make sure the subnet mask has a zero at the end like: 255.255.255.0.

The subnet mask is crucial - it tells your computer which address are local and which ones are not local - if you make the subnet mask 0.0.0.0 then ALL addresses are local.  If you make it 255.255.255.255 then all addresses are not local and it looks for a router.

another solution is a crossover cable but again you have to setup your ip address and the subnet mask.  The modtronix also has a subnet mask and it is probably 255.255.255.0 so it won't be able to reply to you unless you are near the same ip address so again, 10.1.0.2 would be a good address.

This is all quite a pain in the neck (because you have to get off the internet to do it).

Another way to do it - more complicated - would be to configure your router to be on the 10.1.0.10 address with a subnet mask of 255.255.255.0.  Setup dhcp, setup everything, then also possibly change the ip address of all your machines in your house or at work or wherever you are doing this.

secarica

  • Full Member
  • ***
  • Posts: 20
    • View Profile
Re: how can a user change a forgotten username and/or password ?
« Reply #4 on: May 12, 2016, 10:48:46 PM »
As I said, I connected directly (also) via cross cable. Why the need for a router only to connect 2 devices, physically connected only to each other, each with unique IP address ? Especially if these are already working this way very well in non-safe mode.

Default SBC subnet mask address is 255.0.0.0 and I didn't changed it but I also suspect there is no way to change this while in safe mode. Also on PC were the same 255.0.0.0 mask address, which is set (autocompleted) automatically when I specified an 10.1.0.xx local address (where xx was 99 and later 9). At the same time all these settings are working very well in non-safe mode.

Internet ? No need for internet here. Again, what has to do the internet with 2 devices, physically connected only to each other, each with unique IP address ? The final device is a rackmounted relay-based video bypass switch, that has nothing to do with the internet at least not the physical network segment where the SBC65EC is involved.

This (the subject) is specifically about forgotten password (or username). Even if I informed the end user that he must take care of the chosen username and password, I also need to offer him a solution just in case it fails to do so. In one case I can go there and check the module with my PICKit, but generally speaking this is not a solution (and gives a bad reputation of the overall product I mean the one which I built).

Cristi
« Last Edit: May 12, 2016, 10:50:22 PM by secarica »

gr

  • Hero Member
  • *****
  • Posts: 169
    • View Profile
Re: how can a user change a forgotten username and/or password ?
« Reply #5 on: May 13, 2016, 08:23:01 PM »
Well you did all the right things then.  You didn't mention about the subnet and so on in the first post.

So the java boot loader is finicky - I had to play with the timing - reboot the sbc65 sometimes a few seconds before or after you tell the java boot loader to go.  I no longer remember the exact timing.

Also I seem to remember that one of the IP addresses worked better than the other 2 so maybe 192.168.1.1 or 192.168.0.1 works better?

If it were me I would next try wireshark and look at the ARP packets which convert ip address to mac address.