random.4 revision 1.5
$OpenBSD: random.4,v 1.5 1999/05/16 19:56:35 alex Exp $
Copyright (c) 1996, 1997 Michael Shalayeff
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. All advertising materials mentioning features or use of this software
must display the following acknowledgement:
This product includes software developed by Michael Shalayeff.
4. 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)
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LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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SUCH DAMAGE.
.Dd March 25, 1996 .Dt RND 4 .Os OpenBSD .Sh NAME .Nm random , .Nm srandom , .Nm urandom , .Nm prandom , .Nm arandom .Nd random data source devices. .Sh SYNOPSIS .Fd #include <sys/types.h> .Fd #include <dev/rndvar.h> .Fd #include <dev/rndioctl.h> .Sh DESCRIPTION The .Nm device produces random data, with different random quality. {u,s,a}random devices generates random data based on the system activity (like disk and network devices).
Copyright (c) 1996, 1997 Michael Shalayeff
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. All advertising materials mentioning features or use of this software
must display the following acknowledgement:
This product includes software developed by Michael Shalayeff.
4. 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.
.Dd March 25, 1996 .Dt RND 4 .Os OpenBSD .Sh NAME .Nm random , .Nm srandom , .Nm urandom , .Nm prandom , .Nm arandom .Nd random data source devices. .Sh SYNOPSIS .Fd #include <sys/types.h> .Fd #include <dev/rndvar.h> .Fd #include <dev/rndioctl.h> .Sh DESCRIPTION The .Nm device produces random data, with different random quality. {u,s,a}random devices generates random data based on the system activity (like disk and network devices).
p l -hang -width /dev/srandomXXX t /dev/random reserved for nuclear noise generators. t /dev/srandom strong random data. t /dev/urandom same as above, but does not guarantee the data to be strong. t /dev/prandom simple pseudo-random generator (as it is in the kernel). t /dev/arandom aRC4 hashed data (as apposed to the {u,s}random, as they are MD5). .Sh SEE ALSO .Xr arc4random 3 , .Xr md5 3 , .Xr random 3 , .Xr md5 9 , .Xr random 9 .Sh FILES l -tag -width /dev/srandom t Pa /dev/random, /dev/srandom, /dev/urandom, /dev/prandom, /dev/arandom .El .Sh BUGS No randomness testing suite provided. .Sh HISTORY An .Nm device first appeared in Linux operating system.
p aRC4 routines added by David Mazieres.