.\" Copyright (c) 2016 Konrad Witaszczyk <def@FreeBSD.org>
.\" All rights reserved.
.\"
.\" 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 AUTHORS 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 AUTHORS 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.
.\"
.\" $FreeBSD$
.\"
.Dd January 29, 2018
.Dt DECRYPTCORE 8
.Os
.Sh NAME
.Nm decryptcore
.Nd "decrypt a core dump of the operating system"
.Sh SYNOPSIS
.Nm
.Op Fl fLv
.Fl p Ar privatekeyfile
.Fl k Ar keyfile
.Fl e Ar encryptedcore
.Fl c Ar core
.Nm
.Op Fl fLv
.Op Fl d Ar crashdir
.Fl p Ar privatekeyfile
.Fl n Ar dumpnr
.Sh DESCRIPTION
The
.Nm
utility first decrypts
.Ar keyfile
using
.Ar privatekeyfile
and then uses the resulting key to decrypt
.Ar encryptedcore
saved by
.Xr savecore 8 .
The result is saved in
.Ar core .
.Pp
Alternatively a user can decrypt a core dump numbered
.Ar dumpnr
from the
.Ar crashdir
directory.
In this case a dump key from the
.Pa key.#
file is used and the result is saved in the
.Pa vmcore.#
file where
.Dq #
corresponds to
.Ar dumpnr .
.Pp
By default
.Nm
does not overwrite an old core dump as a user might want to store the core
somewhere else for the future.
This behaviour can be changed using the
.Fl f
flag.
.Pp
The
.Nm
utility can be started with the following command line arguments:
.Bl -tag -width ".Fl e Ar encryptedcore"
.It Fl f
Remove a decryped core dump if it already exists.
.It Fl L
Write log messages to
.Xr syslogd 8 .
.It Fl v
Print or log verbose/debugging information.
This option can be specified multiple times to raise the verbosity
level.
.It Fl p Ar privatekeyfile
Specify location of a private key file which will be used to decrypt a dump key
file.
.It Fl k Ar keyfile
Specify location of a dump key file.
.It Fl e Ar encryptedcore
Specify location of an encrypted core.
.It Fl c Ar core
Specify location of a resulting decrypted core dump.
.It Fl d Ar crashdir
Specify an alternative crash dump directory.
The default crash dump directory is
.Pa /var/crash .
.It Fl n Ar dumpnr
Specify a number of a crash dump to be decrypted.
.El
.Sh EXIT STATUS
.Ex -std
.Sh SEE ALSO
.Xr kgdb 1 ,
.Xr capsicum 4 ,
.Xr dumpon 8 ,
.Xr savecore 8 ,
.Xr syslogd 8
.Sh AUTHORS
The
.Nm
utility was implemented by
.An Konrad Witaszczyk Aq Mt def@FreeBSD.org .