This patch adds the function scatterwalk_map_and_copy which reads or
writes a chunk of data from a scatterlist at a given offset. It will
be used by authenc which would read/write the authentication data at
the end of the cipher/plain text.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The existing digest user interface is inadequate for support asynchronous
operations. For one it doesn't return a value to indicate success or
failure, nor does it take a per-operation descriptor which is essential
for the issuing of requests while other requests are still outstanding.
This patch is the first in a series of steps to remodel the interface
for asynchronous operations.
For the ease of transition the new interface will be known as "hash"
while the old one will remain as "digest".
This patch also changes sg_next to allow chaining.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch prepares the scatterwalk code for use by the new block cipher
type.
Firstly it halves the size of scatter_walk on 32-bit platforms. This
is important as we allocate at least two of these objects on the stack
for each block cipher operation.
It also exports the symbols since the block cipher code can be built as
a module.
Finally there is a hack in scatterwalk_unmap that relies on progress
being made. Unfortunately, for hardware crypto we can't guarantee
progress to be made since the hardware can fail.
So this also gets rid of the hack by not advancing the address returned
by scatterwalk_map.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The VIA Padlock device requires the input and output buffers to
be aligned on 16-byte boundaries. This patch adds the alignmask
attribute for low-level cipher implementations to indicate their
alignment requirements.
The mid-level crypt() function will copy the input/output buffers
if they are not aligned correctly before they are passed to the
low-level implementation.
Strictly speaking, some of the software implementations require
the buffers to be aligned on 4-byte boundaries as they do 32-bit
loads. However, it is not clear whether it is better to copy
the buffers or pay the penalty for unaligned loads/stores.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
The VIA Padlock device is able to perform much better when multiple
blocks are fed to it at once. As this device offers an exceptional
throughput rate it is worthwhile to optimise the infrastructure
specifically for it.
We shift the existing page-sized fast path down to the CBC/ECB functions.
We can then replace the CBC/ECB functions with functions provided by the
underlying algorithm that performs the multi-block operations.
As a side-effect this improves the performance of large cipher operations
for all existing algorithm implementations. I've measured the gain to be
around 5% for 3DES and 15% for AES.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Jens Axboe