diff --git a/libexec/save-entropy/Makefile b/libexec/save-entropy/Makefile index 1c7eabf36c7f..0c541606411f 100644 --- a/libexec/save-entropy/Makefile +++ b/libexec/save-entropy/Makefile @@ -1,4 +1,5 @@ SCRIPTS= save-entropy.sh +MAN= save-entropy.8 .include diff --git a/libexec/save-entropy/save-entropy.8 b/libexec/save-entropy/save-entropy.8 new file mode 100644 index 000000000000..f7a93c8866fc --- /dev/null +++ b/libexec/save-entropy/save-entropy.8 @@ -0,0 +1,97 @@ +.\" +.\" SPDX-License-Identifier: BSD-2-Clause +.\" +.\" Copyright (c) 2023 Fernando Apesteguia +.\" +.\" 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. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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 September 18, 2023 +.Dt SAVE-ENTROPY 8 +.Os +.Sh NAME +.Nm save-entropy +.Nd Save bits of entropy to feed /dev/random at startup +.Sh SYNOPSIS +.Nm save-entropy +.Sh DESCRIPTION +The +.Nm +command is used to save entropy data from +.Pa /dev/random +to files in a specified output location. +The files saved are used at startup to provide additional entropy for +.Pa /dev/random . +The output file will be different in every invocation until the maximum number +of different files is reached. +(See +.Em entropy_save_num +for details). +By default this script is invoked via +.Xr cron 8 +every eleven minutes approximately. +.Pp +This command does nothing if executed inside a +.Xr jail 8 . +.Pp +Three variables in +.Pa /etc/rc.conf +regulate the behavior of the script: +.Bl -tag -width Ds +.It Va entropy_dir +Specify the directory for saved entropy files. +Defaults to +.Pa /var/db/entropy . +If set to "NO" it disables caching entropy via +.Xr cron 8 . +This setting is shared with +.Pa /etc/rc.d/random . +.It Va entropy_save_sz +Size of the entropy cache files. +Defaults to 4096. +.It Va entropy_save_num +Number of entropy cache files to save. +Defaults to 8. +.El +.Sh FILES +.Bl -tag -width Ds +.It Pa /etc/rc.conf +.El +.Sh EXIT STATUS +.Ex -std +Errors will be recorded in the system log. +.Sh SEE ALSO +.Xr syslog 3 , +.Xr random 4 , +.Xr rc.conf 5 , +.Xr cron 8 +.Sh HISTORY +The +.Nm +command first appeared in +.Fx 5.0 . +.Sh AUTHORS +The +.Nm +command was originally written by +.An Doug Barton . +This manual page was written by +.An Fernando Apesteguia .