August 6th, 2020, 23:19
August 7th, 2020, 10:53
August 7th, 2020, 11:47
(1) That should be a given]
(2) would be out as the controllers have firmware and I really doubt they would be transplantable.
(3) is less a last resort, but more likely as there is evidence of cases with these controllers solved by chip off.
vendors don't care about data recovery, their extent is if it fails in warranty period, they will replace it. Putting in avenues to recover data in the event of a fail kind of insinuates they will fail at some point and they never want to admit that. Plus it is extra work and code for no ROI.
Another problem is a controller does a lot more than send the data in to the NAND, and is needed to successfully read and write the data. If this failed and only option was a dump from JTAG, this is no better than chip off. data is not stored on the NANDS in any useable form
August 7th, 2020, 14:09
August 9th, 2020, 20:36
thd wrote:(1) That should be a given]
Should be, but as it turns out often is not. It seems that a lot of techs know how to run tools, but have little to no engineering background.(2) would be out as the controllers have firmware and I really doubt they would be transplantable.
Although not impossible, I'd be surprised if the controllers themselves had onboard flash. It's a mixed signal process then, and would typically be much cheaper in terms of silicon to either use a bit of the NAND or put a small bit of SPI NOR flash to hold firmware. So that being said, if a S4LN053X01-8030 really had failed, I can't imagine why replacing it with another identical working part would be a problem. Maybe they have something (serial number, encryption key, who knows what) stored in OTP on them, but that aside...(3) is less a last resort, but more likely as there is evidence of cases with these controllers solved by chip off.
So imagine the case where you have a NAND part where a bank has failed, but it's mostly readable. You dump that part, re-write the data to a good equivalent NAND and replace.vendors don't care about data recovery, their extent is if it fails in warranty period, they will replace it. Putting in avenues to recover data in the event of a fail kind of insinuates they will fail at some point and they never want to admit that. Plus it is extra work and code for no ROI.
I guess, but it's fairly little extra work to put in a read-only/diagnostic mode. Anyhow, as you say, they obviously don't care and are unlikely to change in that regard.Another problem is a controller does a lot more than send the data in to the NAND, and is needed to successfully read and write the data. If this failed and only option was a dump from JTAG, this is no better than chip off. data is not stored on the NANDS in any useable form
Right -- but think a little further here. The MEX is 3 Cortex M4 cores, APB/AHB, the NAND controllers, and whatever other peripherals -- and the firmware is available. Wiring up QEMU et. al. to emulate 3 cores and a small number of peripherals, and then attaching 8 virtual NAND devices containing the data extracted from a "chip off" dump is not an unreasonable way of doing reconstruction. Honestly, given sufficient skill to lift and reball the NAND BGAs for extraction, probably a much safer way to go as you don't risk further damage to the data once captured.
Anyhow, all of this is academic as what I really need is to get access to the data on this SSD right now.
Should be, but as it turns out often is not. It seems that a lot of techs know how to run tools, but have little to no engineering background.
August 10th, 2020, 8:09
HaQue wrote:
I was going to answer each point but that would keep the whole thing "Acedemic" The problem with being Acedemic" is you never actually get to the recovery part - there is always some reasoning where this or that method is better or worse than some other method.
Plus you are making the mistake of thinking flash memory storage is just like any other electronics, and engineers would do what islogical or what makes sense.
There is flash memory on probably all controllers, and I am surprised you didnt just look around for any datasheets to have a look what flash controllers are: basically a mini-pc that runs code. I would be surprised if the WASN'T flash on a controller. The many tools from dodgy parts of the net such as flashboot.ru specifically are designed to update controllers.
I know these come in many configurations, but
HaQue wrote:anyway, I will go into it a bit more..
point (1) - I guess if they started being engineers, they would stick to it and would be a more lucrative usage of their time.
and yet they recover drives day in, day out... and engineers come here to find out how to do it.
I wont argue that a knowledge of at the very least, power and data circuits would be highly benificial, and I would love to understand them as well as @fzabkar that often helps with such.
HaQue wrote:point (2) many flash devices that look exactly the same (part numbers of flash, controller models, exact BOM) have different data/SA layouts, different XOR, etc. Just go to http://www.flash-extractor.com/library/ and look at all the different variations.
HaQue wrote:point (3) maybe, but I thought you wanted data now, not in 3,6,9 months.. Plus I may agree give a sufficiently skilled coder, and someone that had access to the patient drives internal technical specifications and data structures. Or a least a way to discover all of it , which in that case you may as well do chip-off, as you would be dooinfg significant electronics work on the drive anyway. remember this is a black box with no specific documentation of the hardware, and of what the did to it software wise.
HaQue wrote:This is not a flame post BTW, but just my opinion of the situation. We have seen a lot of similar posts where someone who does have skill in electronic engineering will see a future solution, but I think I have only seen 2 cases where it has follwed through to a solution, and many many weeks of work at the very least from others before project dies.
anyway, enoug chit-chat, and good luck with your recovery as well.
August 10th, 2020, 9:09
I see you are in the US, have you considered Ace Data Recovery in Texas?thd wrote:...Before handing off the job to someone who is completely unknown to you though, you want to have a very clear understanding of their capabilities and also a general "plan of attack" for the recovery. If you get and subscribe to those two things, then you can have reasonable comfort that you're in good hands. The worst scenario to end up in is where expectations were misaligned on either or both sides and you end up with permanent loss of your data. This is just about being as careful as possible.
August 10th, 2020, 13:33
Blizzard wrote: I see you are in the US, have you considered Ace Data Recovery in Texas?
August 10th, 2020, 20:21
I do want the data back. I'm not insinuating that a science project is the way to go here, I'm just surprised that a tool like this hasn't been developed. Emulators and simulators are used for all other parts of silicon design (e.g. software is running in co-design on a part long before it's been taped out). It seems like for data recovery, being able to bring a virtual controller online and then selectively enabled/disable parts of it could be useful. I guess with that said, some of the chip off recovery software is just short circuiting that process anyhow.
On their web page, they state that devices they do data recovery on can be returned to Apple for warranty claims. That would seem to suggest that they only employ non-invasive methods.
August 10th, 2020, 20:54
I have referred a number of NVME SSD cases to Ace. At least 3 people reported back that Ace recovered their data. None have reported that they didn't, but we don't outsource so we have only referred the customers. They don't really have any reason to report back to us. One of the people that reported back had an Apple/Samsung 512GB and they said it took 3 months but they received an email update every week. The other 2 were a quick turnaround.HaQue wrote:...As far as I am aware, they are a very decent lab.
August 10th, 2020, 23:23
August 12th, 2020, 13:16
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