On Fri, Jun 23, 2017 at 04:13:41PM +0800, Herbert Xu wrote: > Binoy Jayan <binoy.jayan@xxxxxxxxxx> wrote: > > =============================================================================== > > dm-crypt optimization for larger block sizes > > =============================================================================== > > > > Currently, the iv generation algorithms are implemented in dm-crypt.c. The goal > > is to move these algorithms from the dm layer to the kernel crypto layer by > > implementing them as template ciphers so they can be used in relation with > > algorithms like aes, and with multiple modes like cbc, ecb etc. As part of this > > patchset, the iv-generation code is moved from the dm layer to the crypto layer > > and adapt the dm-layer to send a whole 'bio' (as defined in the block layer) > > at a time. Each bio contains the in memory representation of physically > > contiguous disk blocks. Since the bio itself may not be contiguous in main > > memory, the dm layer sets up a chained scatterlist of these blocks split into > > physically contiguous segments in memory so that DMA can be performed. > > There is currently a patch-set for fscrypt to add essiv support. It > would be interesting to know whether your implementation of essiv > can also be used in that patchset. That would confirm that we're on > the right track. > You can find the fscrypt patch at https://patchwork.kernel.org/patch/9795327/ Note that it's encrypting 4096-byte blocks, not 512-byte. Also, it's using AES-256 for the ESSIV tfm (since it uses a SHA-256 hash) but AES-128 for the "real" encryption. It's possible this is a mistake and it should be AES-128 for both. (If it is, it needs to be fixed before it's released in 4.13.) Eric
