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.TH dnsjit.core.object.dns.label 3 "1.2.3" "dnsjit"
.SH NAME
dnsjit.core.object.dns.label \- Container of a DNS label
.SH DESCRIPTION
The object that describes a DNS label.
To extract a domain name label first check that
.I have_dn
is set, then use
.I "offset + 1"
to indicate where in the payload the label start and
.I length
for how many bytes long it is.
.SS Attributes
.TP
is_end
.TP
have_length
Set if there is a length.
.TP
have_offset
Set if there is an offset.
.TP
have_extension_bits
Set if there is extension bits.
.TP
have_dn
Set if the label contained a domain name.
.TP
extension_bits
The extension bits.
.TP
length
The length of the domain name.
.TP
offset
If
.I have_dn
is set then this contains the offset within the payload to where this label
start otherwise it contains the offset to another label.
.SS Functions
.TP
.BR Label.new "(size)"
Create a new array of labels.
.TP
.BR Label.tostring "(dns, labels, num_labels, offset_labels)"
Returns labels as a string and an offset to the next label.
The string may be nil if the first label was an offset.
The offset may be nil if the last label was an extension bits or end marker.
.TP
.BR Label.tooffstr "(dns, labels, num_labels, offset_labels)"
Returns labels as a string which also includes a textual notation of the
offset in the form of
.IR "<offset>label" .
.SH SEE ALSO
.BR dnsjit.core.object.dns (3)
.SH AUTHORS and CONTRIBUTORS
Jerry Lundström (DNS-OARC),
Tomáš Křížek (CZ.NIC),
Petr Špaček (ISC)
.LP
Maintained by DNS-OARC
.LP
.RS
.I https://www.dns-oarc.net/
.RE
.LP
.SH BUGS
For issues and feature requests please use:
.LP
.RS
\fIhttps://github.com/DNS-OARC/dnsjit/issues\fP
.RE
.LP
For question and help please use:
.LP
.RS
\fIadmin@dns-oarc.net\fP
.RE
.LP