work the same way, grow output buffer exponentially and kill
reallocation of metadata
-minor cleanup, make definitions private which are implementation
details of deflate.gzip
decompression:
-seperate the IPCOMP specific rule that compression must not grow the
data from general compression semantics: Introduce a special name
CRYPTO_DEFLATE_COMP_NOGROW/comp_algo_deflate_nogrow to describe
the IPCOMP semantics and use it there. (being here, fix the check
so that equal size is considered failure as well as required by
RFC2393)
Customers of CRYPTO_DEFLATE_COMP/comp_algo_deflate now always get
deflated data back, even if they are not smaller than the original.
-allow to pass a "size hint" to the DEFLATE decompression function
which is used for the initial buffer allocation. Due to the changes
done there, additional allocations and extra copies are avoided if the
initial allocation is sufficient. Set the size hint to MCLBYTES (=2k)
in IPCOMP which should be good for many use cases.
the DEFLATE complssion/decompression result is within a single
buffer already
-simplify bookkeeping of allocated buffers (and don't waste the
last member of the metadata array)
from Wolfgang Stukenbrock per PR kern/36865 (with some cleanup
of error handling by me)
The Gzip compression case can be improved too, but for now I've applied
the buffer bookkeeping changes.
tested with IP4 IPCOMP
Extends the Opencrypto API to allow the destination buffer size to be
specified when its not the same size as the input buffer (i.e. for
operations like compress and decompress).
The crypto_op and crypt_n_op structures gain a u_int dst_len field.
The session_op structure gains a comp_alg field to specify a compression
algorithm.
Moved four ioctls to new ids; CIOCGSESSION, CIOCNGSESSION, CIOCCRYPT,
and CIOCNCRYPTM.
Added four backward compatible ioctls; OCIOCGSESSION, OCIOCNGSESSION,
OCIOCCRYPT, and OCIOCNCRYPTM.
Backward compatibility is maintained in ocryptodev.h and ocryptodev.c which
implement the original ioctls and set dst_len and comp_alg to 0.
Adds user-space access to compression features.
Adds software gzip support (CRYPTO_GZIP_COMP).
Adds the fast version of crc32 from zlib to libkern. This should be generally
useful and provide a place to start normalizing the various crc32 routines
in the kernel. The crc32 routine is used in this patch to support GZIP.
With input and support from tls@NetBSD.org.
code is derived from Sam Leffler's FreeBSD port of OCF, which is in
turn a port of Angelos Keromytis's OpenBSD work.
Credit to Sam and Angelos, any blame for the NetBSD port to me.
