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Reading SA by tracks

December 24th, 2017, 18:21

Many tools claim to read SA tracks, but they do it by reading PBA's ( sector by sector). Is it possible to read (or verify) SA track by track, assuming we know the proper SuperOn command?

Re: Reading SA by tracks

December 25th, 2017, 11:23

BGman wrote:Many tools claim to read SA tracks, but they do it by reading PBA's ( sector by sector). Is it possible to read (or verify) SA track by track, assuming we know the proper SuperOn command?


You would need Super ON + Vendor Specific Command to read FW tracks...

At any rate i don't know ANY VSC to read by track number without setting at least a number of sectors to read. This even apply to TTL commands for older ST-10.

Also some drives will have unformated sectors on FW tracks.

Maybe you are talking about something like this ?

viewtopic.php?f=28&t=36232

:D :D :D

Re: Reading SA by tracks

December 26th, 2017, 5:44

I'm talking about something like this:
Drive Commands (Samsung VU Commands)
function syntax OP parameter/description requirement
prtk 86h Physical Read Track Physical C/H should be set

Re: Reading SA by tracks

December 26th, 2017, 15:46

It should be possible on "some" Samsung drives to get the entire M/C with a single VSC ....

But i don't think this is what you are looking for.

And if something like you want does exist it will be limited to some drives only.

Re: Reading SA by tracks

December 27th, 2017, 2:04

Spildit wrote:It should be possible on "some" Samsung drives to get the entire M/C with a single VSC ....

But i don't think this is what you are looking for.

This is exactly what I'm looking for - a way to read the entire SA without a risk of errors. Then I could examine the effect of some VSC on the drive by comparing the SA before and after applying the VSC.
Recently I found out that Sediv Toshiba miscalculates in some cases the position of SA and reads wrong tracks. This may happens with other tools , too...They are out of control!

Re: Reading SA by tracks

December 27th, 2017, 2:27

BGman wrote:Recently I found out that Sediv Toshiba miscalculates in some cases the position of SA and reads wrong tracks.

The following thread claims that there is a hidden area in the SA of Toshiba HDDs. Could this be somehow involved?

https://www.data-medics.com/forum/anyon ... t1410.html

mikem wrote:During imaging a drive, resets are important to get a drive out of a particular error state or to flush the drive's buffer memory, this can happen several tens of times an hour and so requires constant resetting. The breakthough we have made is we found a hidden module within the SA of the [Toshiba] drive and have located the exact bit of a byte that stores this flag. We found that changing the flag and saving back to the drive's firmware permanently disables the re-allocation meaning that drives will image normally without lots of intervention and restarting and allows all types of automatic reset and power cycling during imaging.
...
This is not the translator issue. There is a terminal command that turns off bad sector reallocation, it is well known so I wont repost it here, however, when the drive soft or hard resets and on power cycle the reallocation flag is turned back on resulting with slow reads. What was discovered turns off reallocation permanently that survives soft, hard and power cycles. The flag is in a module that is not listed in the standard module list, and is hidden in SA HPA area.

Re: Reading SA by tracks

December 27th, 2017, 6:27

@fzabkar
I think the term HPA is used wrongly, but yes we know too little about the modules in the SA of Toshiba drives.

Re: Reading SA by tracks

December 27th, 2017, 10:05

I think it all depends on how much is known about a particular brand / model. It is not too hard to dump SA by head on WD drives, considering all the information needed can be found. You just have to know the VSC command to read CHS, and of course put the drive in kernel (safe) mode to get access to the negative SA tracks. However, it is not as easy as just sending a single command to read a track.

If it was easy, don't you think all the tools would be doing it?

Re: Reading SA by tracks

December 27th, 2017, 15:10

maximus wrote:If it was easy, don't you think all the tools would be doing it?

Not at all. For them "easy" means "easy to sniff out", so they try to avoid it... :D :D :D

By the way, the SA tracks are not always negative ...

Re: Reading SA by tracks

December 27th, 2017, 15:26

BGman wrote:@fzabkar
I think the term HPA is used wrongly, but yes we know too little about the modules in the SA of Toshiba drives.


Example - The security "module" containing the ATA password (encrypted/encoded) is stored on a "track" on the platter and is NOT enumerated by CP designation meaning that even if you have VSC to read CPs you can't read module "S" on platter. You have to know it's location on track/sector.

Problem is that will change from drive to drive. Even if you can get some of those hidden modules on one drive it doesn't mean that another one from another model will have those modules as well.

3.png

Re: Reading SA by tracks

December 27th, 2017, 15:30

Tools like PC-3000 are coded with info obtained from reversing the firmware on drives and NOT by sniffing VSC from other firmware tools ....

For us it's "easy" to sniff VSC from firmware tools and check what they are doing but for ACE doing the tool to start with they don't have anything to sniff from except oficial firmware update executables and stuff like that and as you might image they don't have commands to remove pwd, regen translator, clear S.M.A.R.T., etc .... to reach to those in the first place and assuming that you don't have any tool to sniff from you have to reverse the firmware code itself to figure out to what VSC it will respond ...

Re: Reading SA by tracks

December 27th, 2017, 17:02

Most likely some trial and arror is required.

If you have the VSC to read tracks/sectors inside the SA range you might want to start dumping all tracks that you can and examine one by one to find "interesting" data ?

And yes, i did notice that SeDiv problem and most likely will afect the other tools as well, not only the Toshiba one.

You can use the read track VSC to read track yourself even if the SeDiv can't read a specific track on a specific model.

Also the SeDiv is missing some variants of the clear/re-set tracks VSC. For example you have clear S.M.A.R.T. and clear password by initializing modules on tracks but there are more commands to initialize more stuff that SeDiv doesn't have.

Re: Reading SA by tracks

December 27th, 2017, 21:07

BGman wrote:
maximus wrote:If it was easy, don't you think all the tools would be doing it?

Not at all. For them "easy" means "easy to sniff out", so they try to avoid it... :D :D :D

By the way, the SA tracks are not always negative ...

Are you a programmer? Or are you just trying to figure out how to do something complicated by using simple commands (which most likely is not possible)?

Re: Reading SA by tracks

December 28th, 2017, 6:23

maximus wrote:Are you a programmer? Or are you just trying to figure out how to do something complicated by using simple commands (which most likely is not possible)?

I'm not a programmer. The programmers make things to look complicated, but they are not....

Re: Reading SA by tracks

December 28th, 2017, 7:47

BGman wrote: The programmers make things to look complicated, but they are not....

:lol:

Re: Reading SA by tracks

December 28th, 2017, 8:39

BGman wrote:I'm not a programmer. The programmers make things to look complicated, but they are not....

Maybe that is my problem, I am a programmer so I always have to do things the hard way... :D :D :D

Re: Reading SA by tracks

December 28th, 2017, 12:10

maximus wrote:Maybe that is my problem, I am a programmer so I always have to do things the hard way... :D :D :D

No, you don't. But maybe you preffer to do things in this way...

Re: Reading SA by tracks

December 28th, 2017, 12:29

If I could only get this darn button to work...
easypushbutton.gif
easypushbutton.gif (624.88 KiB) Viewed 9632 times

Wait, I think I got it...
0gKvND.gif
0gKvND.gif (564.7 KiB) Viewed 9632 times

Re: Reading SA by tracks

December 28th, 2017, 16:04

lolol

:D :D :D
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