* g10/armor.c (CRCINIT, CRCPOLY, CRCUPDATE, crc_table): Remove.
(new_armor_context): Open libgcrypt CRC24 context.
(release_armor_context): Close CRC24 context.
(initialize): Remove CRC table generation.
(get_afx_crc): New.
(check_input, fake_packet, radix64_read, armor_filter): Update to use
CRC24 context.
* g10/filter.h (armor_filter_context_t): Replace crc intermediate value
with libgcrypt md context pointer.
--
This patch changes armor filter to use optimized CRC24 implementation
from libgcrypt to speed up encryption and decryption.
Benchmark results below, tested on Intel Core i7-4790K (turbo off).
Encrypted 2 GiB through pipe to ramfs file using AES128. Decrypt
ramfs file out through pipe to /dev/null.
before patch-set
----------------
gpg process
armor: user time pipe transfer rate
encrypt-aead: 13.8 140 MB/s
decrypt-aead: 30.6 68 MB/s
encrypt-cfb: 17.4 114 MB/s
decrypt-cfb: 32.6 64 MB/s
after (decrypt+iobuf+crc opt)
-----------------------------
gpg process
armor: user time pipe transfer rate
encrypt-aead: 8.7 211 MB/s
decrypt-aead: 17.6 116 MB/s
encrypt-cfb: 12.6 153 MB/s
decrypt-cfb: 19.6 105 MB/s
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@iki.fi>