Re: [PATCH 4/4] crypto: algif_skcipher - User-space interface for skcipher operations

[David Miller <davem@davemloft.net>]

From: Herbert Xu <herbert@gondor.apana.org.au>
Date: Thu, 04 Nov 2010 12:36:20 -0500

> crypto: algif_skcipher - User-space interface for skcipher operations
> 
> This patch adds the af_alg plugin for symmetric key ciphers,
> corresponding to the ablkcipher kernel operation type.
> 
> Keys can optionally be set through the setsockopt interface.
> 
> Once a sendmsg call occurs without MSG_MORE no further writes
> may be made to the socket until all previous data has been read.
> 
> IVs and and whether encryption/decryption is performed can be
> set through the setsockopt interface or as a control message
> to sendmsg.
> 
> The interface is completely synchronous, all operations are
> carried out in recvmsg(2) and will complete prior to the system
> call returning.
> 
> The splice(2) interface support reading the user-space data directly
> without copying (except that the Crypto API itself may copy the data
> if alignment is off).
> 
> The recvmsg(2) interface supports directly writing to user-space
> without additional copying, i.e., the kernel crypto interface will
> receive the user-space address as its output SG list.
> 
> Thakns to Miloslav Trmac for reviewing this and contributing
> fixes and improvements.
> 
> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

Acked-by: David S. Miller <davem@davemloft.net>