[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]

[dm-devel] dm-verity usage help related

Hello ,
I am new to dm-verity and I am finding it hard to use it.

This is my setup.On one VM running Ubuntu-12.04,I have a nfs-share partition 

on which I have virtual disk image files of other vm's.I want to perform the integrity 

check on these files/nfs-share.

My nfs-share partition (/dev/sdb1 mounted at /nfs-share) size is 10GB.From the 

documentation,I see the numbers 4096,4096,52224,1,root_hash and salt.

I know the doc says
4096 = datablock
4096 = hashblock
52224 = number of blocks
1 = hash offset

SIZE=$(blockdev --getsz /dev/sdb)

dmsetup create name -r --table "0 $SIZE verity 1 /dev/sdb /dev/sdc 4096 
4096 52224 1 sha256 <root_hash> <salt>"

But my question how do I get these values for my setup? How do I know the size

 of data block /hashblock in my case?How I calculate the number of blocks and 

root hash and salt to feed into the command.Can you please let me know the 

process to get these values?       

Also it mentions to use verity setup command for this purpose.Can you let me know 

the arguments or an example here?   

Looking forward to your reply and help.

[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]