.\" --8-LICENSE--
.\"
.\" $Revision: 1.31 $
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.Dd March 22, 2024
.ds volume-ds-DCC Distributed Checksum Clearinghouse
.Dt dccsight 8 DCC
.Os " "
.Sh NAME
.Nm dccsight
.Nd Distributed Checksum Clearinghouse raw checksum interface
.Sh SYNOPSIS
.Nm dccsight
.Bk -words
.Op Fl VdPQC
.Op Fl h Ar homedir
.Op Fl m Ar map
.Op Fl w Ar whiteclnt
.Op Fl t Ar targets
.Op Fl i Ar infile
.Op Fl L Ar ltype,facility.level
.Ek
.Sh DESCRIPTION
.Nm Dccsight
reads one or more lines containing DCC checksums,
reports them to a DCC server,
and writes a X-DCC header line.
It can be used to report checksums obtained from
.Xr dccproc 8
using
.Fl C .
.Ss OPTIONS
The following options are available:
.Bl -tag -width 3n
.It Fl V
displays the version of the DCC raw checksum interface.
Two or more
.Fl V
options show the options with which it was built.
.It Fl d
enables debugging output from the DCC client software.
Additional
.Fl d
options increase the number of messages.
.It Fl P
The SpamAsassin DCC.pm plugin should watch for "bulk" in X-DCC SMTP header
fields, but historically has looked for counts of "many".
However, there are situations when
.Nm
knows that a mail message is extremely bulky and probably spam.
For example, mail from a sender that is blacklisted in
.Pa whiteclnt
gets an X-DCC header that includes
.Em bulk .
To acommodate that bug in SpamAssassin, by default whenever
.Nm
generates an X-DCC header containing "bulk",
it also forces the
.Em Body
count to "many".
.Fl P
turns off that kludge and the
.Em Body
contains the count from the DCC server.
.It Fl Q
only queries the DCC server about the checksums of messages
instead of reporting.
This is useful when
.Nm
is used to filter mail that has already been reported to a DCC
server by another DCC client.
No single mail message should be reported to a DCC
server more than once per recipient,
because each report will increase the apparent "bulkness" of the message.
.Pp
It is better to use
.Em MXDCC
lines in the global
.Pa @prefix@/whiteclnt
file for your MX mail servers that use DCC than to use
.Fl Q
with
.Nm .
.Pp
Do not use
.Fl Q
except on mail that you know has been reported to a DCC server.
DCC depends on reports of all except known private mail and
works only because almost no DCC installations use
.Fl Q .
.It Fl C
outputs the checksums for the message as well as the X-DCC header.
.It Fl h Ar homedir
overrides the default DCC home directory,
.Pa @prefix@ .
.It Fl m Ar map
specifies a name or path of the memory mapped parameter file instead
of the default
.Pa @prefix@/map
in the DCC home directory.
It should be created with the
.Xr cdcc 8
command.
.It Fl w Ar whiteclnt
specifies an optional file containing SMTP client IP addresses and
SMTP headers
of mail that do not need X-DCC headers and whose checksums should not
be reported to the DCC server.
It can also contain checksums of spam.
If the pathname is not absolute, it is relative to the DCC home directory.
Thus, individual users with private whitelists usually specify them
with absolute paths.
It is useful to
.Ar include
a common or system-wide whitelist in private lists.
.Pp
The format of the
.Nm
whiteclnt file is the same as the
.Pa @prefix@/whitelist
file required by
.Xr dbclean 8
and
.Xr dccsight 8 .
Because this list is used frequently, a companion file is used.
It has the same pathname but with an added suffix of
.Ar .dccw .
After being created empty,
it will contain an automatic memory mapped hash table of the main file.
.It Fl t Ar targets
specifies the number of addressees of the message if other than 1.
The string
.Ar many
instead of a number asserts that there were too many addressees
and that the message is unsolicited bulk email.
.It Fl i Ar infile
specifies an input file
instead of standard input.
If not absolute, the pathname is interpreted relative to the
directory in which
.Nm
was started.
.It Fl L Ar ltype,facility.level
specifies how messages should be logged.
.Ar Ltype
must be
.Ar error ,
.Ar info ,
or
.Ar off
to indicate which of the two types of messages are being controlled or
to turn off all
.Xr syslog 3
messages from
.Nm .
.Ar Level
must be a
.Xr syslog 3
level among
.Ar EMERG ,
.Ar ALERT ,
.Ar CRIT , ERR ,
.Ar WARNING ,
.Ar NOTICE ,
.Ar INFO ,
and
.Ar DEBUG .
.Ar Facility
must be among
.Ar AUTH ,
.Ar AUTHPRIV ,
.Ar CRON ,
.Ar DAEMON ,
.Ar FTP ,
.Ar KERN ,
.Ar LPR ,
.Ar MAIL ,
.Ar NEWS ,
.Ar USER ,
.Ar UUCP ,
and
.Ar LOCAL0
through
.Ar LOCAL7 .
The default is equivalent to
.Dl Fl L Ar info,MAIL.NOTICE  Fl L Ar error,MAIL.ERR
.El
.Pp
.Nm
exits 0 on success, and >0 if an error occurs.
.Sh FILES
.Bl -tag -width whiteclnt -compact
.It Pa @prefix@
DCC home directory.
.It Pa map
memory mapped file in the DCC home directory
of information concerning DCC servers.
.It Pa whiteclnt
contains the client whitelist in
the format described in
.Xr dcc 8 .
.It Pa whiteclnt.dccw
memory mapped hash table of the
.Pa @prefix@/whiteclnt
file.
.El
.Sh SEE ALSO
.Xr cdcc 8 ,
.Xr dcc 8 ,
.Xr dbclean 8 ,
.Xr dccd 8 ,
.Xr dblist 8 ,
.Xr dccproc 8 ,
.Xr dccm 8 ,
.Xr dccifd 8 ,
.Xr mail 1 ,
.Xr procmail 1 .
.Sh HISTORY
Implementation of
.Nm
was started at Rhyolite Software in 2000.
This document describes version RHYOLITE_VERSION.