84d9c625bf
- Fix for possible unset uid/gid in toproto
- Fix for default mtree style
- Update libelf
- Importing libexecinfo
- Resynchronize GCC, mpc, gmp, mpfr
- build.sh: Replace params with show-params.
This has been done as the make target has been renamed in the same
way, while a new target named params has been added. This new
target generates a file containing all the parameters, instead of
printing it on the console.
- Update test48 with new etc/services (Fix by Ben Gras <ben@minix3.org)
get getservbyport() out of the inner loop
Change-Id: Ie6ad5226fa2621ff9f0dee8782ea48f9443d2091
91 lines
3 KiB
Groff
91 lines
3 KiB
Groff
.\" Copyright (c) 1990, 1991, 1993
|
|
.\" The Regents of the University of California. All rights reserved.
|
|
.\"
|
|
.\" This code is derived from software contributed to Berkeley by
|
|
.\" Chris Torek and the American National Standards Committee X3,
|
|
.\" on Information Processing Systems.
|
|
.\"
|
|
.\" Redistribution and use in source and binary forms, with or without
|
|
.\" modification, are permitted provided that the following conditions
|
|
.\" are met:
|
|
.\" 1. Redistributions of source code must retain the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer.
|
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer in the
|
|
.\" documentation and/or other materials provided with the distribution.
|
|
.\" 3. Neither the name of the University nor the names of its contributors
|
|
.\" may be used to endorse or promote products derived from this software
|
|
.\" without specific prior written permission.
|
|
.\"
|
|
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
|
|
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
|
|
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
.\" SUCH DAMAGE.
|
|
.\"
|
|
.\" from: @(#)memcmp.3 8.1 (Berkeley) 6/4/93
|
|
.\" $NetBSD: memcmp.3,v 1.11 2013/06/24 04:21:20 riastradh Exp $
|
|
.\"
|
|
.Dd June 23, 2013
|
|
.Dt MEMCMP 3
|
|
.Os
|
|
.Sh NAME
|
|
.Nm memcmp
|
|
.Nd compare byte string
|
|
.Sh LIBRARY
|
|
.Lb libc
|
|
.Sh SYNOPSIS
|
|
.In string.h
|
|
.Ft int
|
|
.Fn memcmp "const void *b1" "const void *b2" "size_t len"
|
|
.Sh DESCRIPTION
|
|
The
|
|
.Fn memcmp
|
|
function
|
|
compares byte string
|
|
.Fa b1
|
|
against byte string
|
|
.Fa b2 .
|
|
Both strings are assumed to be
|
|
.Fa len
|
|
bytes long.
|
|
.Sh RETURN VALUES
|
|
The
|
|
.Fn memcmp
|
|
function
|
|
returns zero if the two strings are identical,
|
|
otherwise returns the difference between the first two differing bytes
|
|
(treated as unsigned char values, so that
|
|
.Sq Li \e200
|
|
is greater than
|
|
.Sq Li \&\e0 ,
|
|
for example).
|
|
Zero-length strings are always identical.
|
|
.Pp
|
|
Do not use
|
|
.Fn memcmp
|
|
to compare cryptographic secrets, because the time it takes varies
|
|
depending on how many bytes are the same, and thus leaks information
|
|
about the two strings by a timing side channel.
|
|
To compare secrets, hashes, message authentication codes, etc., use
|
|
.Xr consttime_memequal 3
|
|
instead.
|
|
.Sh SEE ALSO
|
|
.Xr bcmp 3 ,
|
|
.Xr consttime_memequal 3 ,
|
|
.Xr strcasecmp 3 ,
|
|
.Xr strcmp 3 ,
|
|
.Xr strcoll 3 ,
|
|
.Xr strxfrm 3
|
|
.Sh STANDARDS
|
|
The
|
|
.Fn memcmp
|
|
function
|
|
conforms to
|
|
.St -ansiC .
|