Plausible Deniability With LUKS Posted:

Linux Brujo

In this article I'll tell you how to set up hidden crypto-container using regular means of Linux OS (LUKS and cryptsetup). Standard features of LUKS (such as using external headers and placing actual data by predefined offset) allow user to access hidden data within existing container and deny existence of such data.

UPD[31/05/2014]: This post was ready more than a month ago, and those days I could not even imagine such strange sudden death of TrueCrypt. Well, maybe this project isn't completely dead, let's see… Nevertheless in the following text I leave references to TrueCrypt as is.

What is “plausible deniability”?

You can find very long and detailed definition of this term in Wikipedia: http://en.wikipedia.org/wiki/Plausible_deniability. In short it means that you can do or have something and nobody can suspect and prove that (if you don't admit it, of course). And then you can deny having or doing that thing, if someone want to accuse you, because (let's repeat it) nobody can prove it. E.g., if a kid kicks his little brother's ass while nobody see and the brother goes for seeking justice to their parents, then what happens?

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How To Knock Sense Into HDD Posted:

Linux Brujo

A couple of days ago I saved two my HDDs using a sort of magic.

Symptoms were almost identical: during the boot up OS dumped on a terminal a bunch of errors, and the same errors regularly appeared in logs. It was somewhat like this: 

Mar 31 07:31:31 rohan kernel: [    1.640757] ata5.00: exception Emask 0x0 SAct 0x1 SErr 0x0 action 0x0
Mar 31 07:31:31 rohan kernel: [    1.641114] ata5.00: irq_stat 0x40000008
Mar 31 07:31:31 rohan kernel: [    1.641317] ata5.00: failed command: READ FPDMA QUEUED
Mar 31 07:31:31 rohan kernel: [    1.641582] ata5.00: cmd 60/08:00:50:00:02/00:00:00:00:00/40 tag 0 ncq 4096 in
Mar 31 07:31:31 rohan kernel: [    1.641582]          res 41/40:00:52:00:02/00:00:00:00:00/40 Emask 0x409 (media error) <F>
Mar 31 07:31:31 rohan kernel: [    1.642365] ata5.00: status: { DRDY ERR }
Mar 31 07:31:31 rohan kernel: [    1.642570] ata5.00: error: { UNC }
Mar 31 07:31:31 rohan kernel: [    1.650046] ata5.00: configured for UDMA/133
Mar 31 07:31:31 rohan kernel: [    1.650057] sd 4:0:0:0: [sdb] Unhandled sense code
Mar 31 07:31:31 rohan kernel: [    1.650061] sd 4:0:0:0: [sdb]
Mar 31 07:31:31 rohan kernel: [    1.650064] Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE
Mar 31 07:31:31 rohan kernel: [    1.650067] sd 4:0:0:0: [sdb]
Mar 31 07:31:31 rohan kernel: [    1.650069] Sense Key : Medium Error [current] [descriptor]
Mar 31 07:31:31 rohan kernel: [    1.650075] Descriptor sense data with sense descriptors (in hex):
Mar 31 07:31:31 rohan kernel: [    1.650078]         72 03 11 04 00 00 00 0c 00 0a 80 00 00 00 00 00
Mar 31 07:31:31 rohan kernel: [    1.650094]         00 02 00 52
Mar 31 07:31:31 rohan kernel: [    1.650101] sd 4:0:0:0: [sdb]
Mar 31 07:31:31 rohan kernel: [    1.650104] Add. Sense: Unrecovered read error - auto reallocate failed
Mar 31 07:31:31 rohan kernel: [    1.650108] sd 4:0:0:0: [sdb] CDB:
Mar 31 07:31:31 rohan kernel: [    1.650110] Read(10): 28 00 00 02 00 50 00 00 08 00
Mar 31 07:31:31 rohan kernel: [    1.650123] end_request: I/O error, dev sdb, sector 131154
Mar 31 07:31:31 rohan kernel: [    1.650416] Buffer I/O error on device sdb2, logical block 1
Mar 31 07:31:31 rohan kernel: [    1.650711] ata5: EH complete

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