xref: /freebsd/share/man/man4/aesni.4 (revision 243e928310d073338c5ec089f0dce238a80b9866)
1.\" Copyright (c) 2010 Konstantin Belousov <kib@FreeBSD.org>
2.\" All rights reserved.
3.\"
4.\" Redistribution and use in source and binary forms, with or without
5.\" modification, are permitted provided that the following conditions
6.\" are met:
7.\" 1. Redistributions of source code must retain the above copyright
8.\"    notice, this list of conditions and the following disclaimer.
9.\" 2. Redistributions in binary form must reproduce the above copyright
10.\"    notice, this list of conditions and the following disclaimer in the
11.\"    documentation and/or other materials provided with the distribution.
12.\"
13.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
14.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
17.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23.\" SUCH DAMAGE.
24.\"
25.\" $FreeBSD$
26.\"
27.Dd December 14, 2015
28.Dt AESNI 4
29.Os
30.Sh NAME
31.Nm aesni
32.Nd "driver for the AES accelerator on Intel CPUs"
33.Sh SYNOPSIS
34To compile this driver into the kernel,
35place the following lines in your
36kernel configuration file:
37.Bd -ragged -offset indent
38.Cd "device crypto"
39.Cd "device cryptodev"
40.Cd "device aesni"
41.Ed
42.Pp
43Alternatively, to load the driver as a
44module at boot time, place the following line in
45.Xr loader.conf 5 :
46.Bd -literal -offset indent
47aesni_load="YES"
48.Ed
49.Sh DESCRIPTION
50Starting with some models of Core i5/i7, Intel processors implement
51a new set of instructions called AESNI.
52The set of six instructions accelerates the calculation of the key
53schedule for key lengths of 128, 192, and 256 of the Advanced
54Encryption Standard (AES) symmetric cipher, and provides a hardware
55implementation of the regular and the last encryption and decryption
56rounds.
57.Pp
58The processor capability is reported as AESNI in the Features2 line at boot.
59The
60.Nm
61driver does not attach on systems that lack the required CPU capability.
62.Pp
63The
64.Nm
65driver registers itself to accelerate AES operations for
66.Xr crypto 4 .
67Besides speed, the advantage of using the
68.Nm
69driver is that the AESNI operation
70is data-independent, thus eliminating some attack vectors based on
71measuring cache use and timings typically present in table-driven
72implementations.
73.Sh SEE ALSO
74.Xr crypt 3 ,
75.Xr crypto 4 ,
76.Xr intro 4 ,
77.Xr ipsec 4 ,
78.Xr padlock 4 ,
79.Xr random 4 ,
80.Xr crypto 9
81.Sh HISTORY
82The
83.Nm
84driver first appeared in
85.Fx 9.0 .
86.Sh AUTHORS
87.An -nosplit
88The
89.Nm
90driver was written by
91.An Konstantin Belousov Aq Mt kib@FreeBSD.org .
92The key schedule calculation code was adopted from the sample provided
93by Intel and used in the analogous
94.Ox
95driver.
96