00b67f09dd
Also known as ISC bind. This import adds utilities such as host(1), dig(1), and nslookup(1), as well as many other tools and libraries. Change-Id: I035ca46e64f1965d57019e773f4ff0ef035e4aa3
256 lines
9.5 KiB
Plaintext
256 lines
9.5 KiB
Plaintext
<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
|
|
"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"
|
|
[<!ENTITY mdash "—">]>
|
|
<!--
|
|
- Copyright (C) 2004, 2005, 2007, 2014 Internet Systems Consortium, Inc. ("ISC")
|
|
- Copyright (C) 2000, 2001 Internet Software Consortium.
|
|
-
|
|
- Permission to use, copy, modify, and/or distribute this software for any
|
|
- purpose with or without fee is hereby granted, provided that the above
|
|
- copyright notice and this permission notice appear in all copies.
|
|
-
|
|
- THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
|
|
- REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
|
|
- AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
|
|
- INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
|
|
- LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
|
|
- OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
|
|
- PERFORMANCE OF THIS SOFTWARE.
|
|
-->
|
|
|
|
<refentry>
|
|
|
|
<refentryinfo>
|
|
<date>June 18, 2007</date>
|
|
</refentryinfo>
|
|
|
|
<refmeta>
|
|
<refentrytitle>lwres_noop</refentrytitle>
|
|
<manvolnum>3</manvolnum>
|
|
<refmiscinfo>BIND9</refmiscinfo>
|
|
</refmeta>
|
|
|
|
<docinfo>
|
|
<copyright>
|
|
<year>2004</year>
|
|
<year>2005</year>
|
|
<year>2007</year>
|
|
<year>2014</year>
|
|
<holder>Internet Systems Consortium, Inc. ("ISC")</holder>
|
|
</copyright>
|
|
<copyright>
|
|
<year>2000</year>
|
|
<year>2001</year>
|
|
<holder>Internet Software Consortium.</holder>
|
|
</copyright>
|
|
</docinfo>
|
|
|
|
<refnamediv>
|
|
<refname>lwres_nooprequest_render</refname>
|
|
<refname>lwres_noopresponse_render</refname>
|
|
<refname>lwres_nooprequest_parse</refname>
|
|
<refname>lwres_noopresponse_parse</refname>
|
|
<refname>lwres_noopresponse_free</refname>
|
|
<refname>lwres_nooprequest_free</refname>
|
|
<refpurpose>lightweight resolver no-op message handling</refpurpose>
|
|
</refnamediv>
|
|
<refsynopsisdiv>
|
|
<funcsynopsis>
|
|
<funcsynopsisinfo>
|
|
#include <lwres/lwres.h></funcsynopsisinfo>
|
|
<funcprototype>
|
|
<funcdef>
|
|
lwres_result_t
|
|
<function>lwres_nooprequest_render</function></funcdef>
|
|
<paramdef>lwres_context_t *<parameter>ctx</parameter></paramdef>
|
|
<paramdef>lwres_nooprequest_t *<parameter>req</parameter></paramdef>
|
|
<paramdef>lwres_lwpacket_t *<parameter>pkt</parameter></paramdef>
|
|
<paramdef>lwres_buffer_t *<parameter>b</parameter></paramdef>
|
|
</funcprototype>
|
|
<funcprototype>
|
|
<funcdef>
|
|
lwres_result_t
|
|
<function>lwres_noopresponse_render</function></funcdef>
|
|
<paramdef>lwres_context_t *<parameter>ctx</parameter></paramdef>
|
|
<paramdef>lwres_noopresponse_t *<parameter>req</parameter></paramdef>
|
|
<paramdef>lwres_lwpacket_t *<parameter>pkt</parameter></paramdef>
|
|
<paramdef>lwres_buffer_t *<parameter>b</parameter></paramdef>
|
|
</funcprototype>
|
|
<funcprototype>
|
|
<funcdef>
|
|
lwres_result_t
|
|
<function>lwres_nooprequest_parse</function></funcdef>
|
|
<paramdef>lwres_context_t *<parameter>ctx</parameter></paramdef>
|
|
<paramdef>lwres_buffer_t *<parameter>b</parameter></paramdef>
|
|
<paramdef>lwres_lwpacket_t *<parameter>pkt</parameter></paramdef>
|
|
<paramdef>lwres_nooprequest_t **<parameter>structp</parameter></paramdef>
|
|
</funcprototype>
|
|
<funcprototype>
|
|
<funcdef>
|
|
lwres_result_t
|
|
<function>lwres_noopresponse_parse</function></funcdef>
|
|
<paramdef>lwres_context_t *<parameter>ctx</parameter></paramdef>
|
|
<paramdef>lwres_buffer_t *<parameter>b</parameter></paramdef>
|
|
<paramdef>lwres_lwpacket_t *<parameter>pkt</parameter></paramdef>
|
|
<paramdef>lwres_noopresponse_t **<parameter>structp</parameter></paramdef>
|
|
</funcprototype>
|
|
<funcprototype>
|
|
<funcdef>
|
|
void
|
|
<function>lwres_noopresponse_free</function></funcdef>
|
|
<paramdef>lwres_context_t *<parameter>ctx</parameter></paramdef>
|
|
<paramdef>lwres_noopresponse_t **<parameter>structp</parameter></paramdef>
|
|
</funcprototype>
|
|
<funcprototype>
|
|
<funcdef>
|
|
void
|
|
<function>lwres_nooprequest_free</function></funcdef>
|
|
<paramdef>lwres_context_t *<parameter>ctx</parameter></paramdef>
|
|
<paramdef>lwres_nooprequest_t **<parameter>structp</parameter></paramdef>
|
|
</funcprototype>
|
|
</funcsynopsis>
|
|
</refsynopsisdiv>
|
|
<refsect1>
|
|
<title>DESCRIPTION</title>
|
|
<para>
|
|
These are low-level routines for creating and parsing
|
|
lightweight resolver no-op request and response messages.
|
|
</para>
|
|
<para>
|
|
The no-op message is analogous to a <command>ping</command>
|
|
packet:
|
|
a packet is sent to the resolver daemon and is simply echoed back.
|
|
The opcode is intended to allow a client to determine if the server is
|
|
operational or not.
|
|
</para>
|
|
<para>
|
|
There are four main functions for the no-op opcode.
|
|
One render function converts a no-op request structure —
|
|
<type>lwres_nooprequest_t</type> —
|
|
to the lightweight resolver's canonical format.
|
|
It is complemented by a parse function that converts a packet in this
|
|
canonical format to a no-op request structure.
|
|
Another render function converts the no-op response structure —
|
|
<type>lwres_noopresponse_t</type>
|
|
to the canonical format.
|
|
This is complemented by a parse function which converts a packet in
|
|
canonical format to a no-op response structure.
|
|
</para>
|
|
<para>
|
|
These structures are defined in
|
|
<filename>lwres/lwres.h</filename>.
|
|
|
|
They are shown below.
|
|
</para>
|
|
<para><programlisting>
|
|
#define LWRES_OPCODE_NOOP 0x00000000U
|
|
</programlisting>
|
|
</para>
|
|
<para><programlisting>
|
|
typedef struct {
|
|
lwres_uint16_t datalength;
|
|
unsigned char *data;
|
|
} lwres_nooprequest_t;
|
|
</programlisting>
|
|
</para>
|
|
<para><programlisting>
|
|
typedef struct {
|
|
lwres_uint16_t datalength;
|
|
unsigned char *data;
|
|
} lwres_noopresponse_t;
|
|
</programlisting>
|
|
</para>
|
|
<para>
|
|
Although the structures have different types, they are identical.
|
|
This is because the no-op opcode simply echos whatever data was sent:
|
|
the response is therefore identical to the request.
|
|
</para>
|
|
|
|
<para><function>lwres_nooprequest_render()</function>
|
|
uses resolver context <parameter>ctx</parameter> to convert
|
|
no-op request structure <parameter>req</parameter> to canonical
|
|
format. The packet header structure <parameter>pkt</parameter>
|
|
is initialised and transferred to buffer
|
|
<parameter>b</parameter>. The contents of
|
|
<parameter>*req</parameter> are then appended to the buffer in
|
|
canonical format.
|
|
<function>lwres_noopresponse_render()</function> performs the
|
|
same task, except it converts a no-op response structure
|
|
<type>lwres_noopresponse_t</type> to the lightweight resolver's
|
|
canonical format.
|
|
</para>
|
|
|
|
<para><function>lwres_nooprequest_parse()</function>
|
|
uses context <parameter>ctx</parameter> to convert the contents
|
|
of packet <parameter>pkt</parameter> to a
|
|
<type>lwres_nooprequest_t</type> structure. Buffer
|
|
<parameter>b</parameter> provides space to be used for storing
|
|
this structure. When the function succeeds, the resulting
|
|
<type>lwres_nooprequest_t</type> is made available through
|
|
<parameter>*structp</parameter>.
|
|
<function>lwres_noopresponse_parse()</function> offers the same
|
|
semantics as <function>lwres_nooprequest_parse()</function>
|
|
except it yields a <type>lwres_noopresponse_t</type> structure.
|
|
</para>
|
|
|
|
<para><function>lwres_noopresponse_free()</function>
|
|
and <function>lwres_nooprequest_free()</function> release the
|
|
memory in resolver context <parameter>ctx</parameter> that was
|
|
allocated to the <type>lwres_noopresponse_t</type> or
|
|
<type>lwres_nooprequest_t</type> structures referenced via
|
|
<parameter>structp</parameter>.
|
|
</para>
|
|
|
|
</refsect1>
|
|
<refsect1>
|
|
<title>RETURN VALUES</title>
|
|
<para>
|
|
The no-op opcode functions
|
|
<function>lwres_nooprequest_render()</function>,
|
|
|
|
<function>lwres_noopresponse_render()</function>
|
|
<function>lwres_nooprequest_parse()</function>
|
|
and
|
|
<function>lwres_noopresponse_parse()</function>
|
|
all return
|
|
<errorcode>LWRES_R_SUCCESS</errorcode>
|
|
on success.
|
|
They return
|
|
<errorcode>LWRES_R_NOMEMORY</errorcode>
|
|
if memory allocation fails.
|
|
<errorcode>LWRES_R_UNEXPECTEDEND</errorcode>
|
|
is returned if the available space in the buffer
|
|
<parameter>b</parameter>
|
|
is too small to accommodate the packet header or the
|
|
<type>lwres_nooprequest_t</type>
|
|
and
|
|
<type>lwres_noopresponse_t</type>
|
|
structures.
|
|
<function>lwres_nooprequest_parse()</function>
|
|
and
|
|
<function>lwres_noopresponse_parse()</function>
|
|
will return
|
|
<errorcode>LWRES_R_UNEXPECTEDEND</errorcode>
|
|
if the buffer is not empty after decoding the received packet.
|
|
These functions will return
|
|
<errorcode>LWRES_R_FAILURE</errorcode>
|
|
if
|
|
<constant>pktflags</constant>
|
|
in the packet header structure
|
|
<type>lwres_lwpacket_t</type>
|
|
indicate that the packet is not a response to an earlier query.
|
|
</para>
|
|
</refsect1>
|
|
<refsect1>
|
|
<title>SEE ALSO</title>
|
|
<para><citerefentry>
|
|
<refentrytitle>lwres_packet</refentrytitle><manvolnum>3</manvolnum>
|
|
</citerefentry>
|
|
</para>
|
|
</refsect1>
|
|
</refentry><!--
|
|
- Local variables:
|
|
- mode: sgml
|
|
- End:
|
|
-->
|