826N/A - Copyright (C) 2001 Internet Software Consortium. 826N/A - Permission to use, copy, modify, and distribute this software for any 826N/A - purpose with or without fee is hereby granted, provided that the above 826N/A - copyright notice and this permission notice appear in all copies. 826N/A - THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM 826N/A - DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL 826N/A - IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL 826N/A - INTERNET SOFTWARE CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, 826N/A - INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING 826N/A - FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, 826N/A - NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION 826N/A - WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 826N/ACONTENT="Modular DocBook HTML Stylesheet Version 1.61 1878N/A>lwres_lwpacket_renderheader, lwres_lwpacket_parseheader -- lightweight resolver packet handling functions</
DIV 961N/ACLASS="FUNCSYNOPSISINFO" 961N/ACLASS="FUNCSYNOPSISINFO" 961N/ACLASS="FUNCSYNOPSISINFO" 961N/Alwres_lwpacket_renderheader</
CODE 961N/A>(lwres_buffer_t *b, lwres_lwpacket_t *pkt);</
CODE 826N/Alwres_lwpacket_parseheader</
CODE 826N/A>(lwres_buffer_t *b, lwres_lwpacket_t *pkt);</
CODE 826N/A>These functions rely on a
961N/A>struct lwres_lwpacket</
SPAN 961N/A>typedef struct lwres_lwpacket lwres_lwpacket_t;
961N/A lwres_uint16_t version;
961N/A lwres_uint16_t pktflags;
961N/A lwres_uint32_t recvlength;
961N/A lwres_uint16_t authtype;
lwres_uint16_t authlength;
>The elements of this structure are:
>the overall packet length, including the entire packet header.
This field is filled in by the lwres_gabn_*() and lwres_gnba_*()
>the header format. There is currently only one format,
>LWRES_LWPACKETVERSION_0</
SPANThis field is filled in by the lwres_gabn_*() and lwres_gnba_*()
>library-defined flags for this packet: for instance whether the packet
is a request or a reply. Flag values can be set, but not defined by
This field is filled in by the application wit the exception of the
LWRES_LWPACKETFLAG_RESPONSE bit, which is set by the library in the
lwres_gabn_*() and lwres_gnba_*() calls.</
P>is set by the requestor and is returned in all replies. If two or more
packets from the same source have the same serial number and are from
the same source, they are assumed to be duplicates and the latter ones
This field must be set by the application.</
P>indicates the operation.
Opcodes between 0x00000000 and 0x03ffffff are
reserved for use by the lightweight resolver library. Opcodes between
0x04000000 and 0xffffffff are application defined.
This field is filled in by the lwres_gabn_*() and lwres_gnba_*()
>is only valid for replies.
Results between 0x04000000 and 0xffffffff are application defined.
Results between 0x00000000 and 0x03ffffff are reserved for library use.
This field is filled in by the lwres_gabn_*() and lwres_gnba_*()
>is the maximum buffer size that the receiver can handle on requests
and the size of the buffer needed to satisfy a request when the buffer
is too large for replies.
This field is supplied by the application.</
P>defines the packet level authentication that is used.
Authorisation types between 0x1000 and 0xffff are application defined
and types between 0x0000 and 0x0fff are reserved for library use.
Currently these are not used and must be zero.</
P>gives the length of the authentication data.
Since packet authentication is currently not used, this must be zero.</
P>The following opcodes are currently defined:
>Success is always returned and the packet contents are echoed.
The lwres_noop_*() functions should be used for this type.</
P>returns all known addresses for a given name.
The lwres_gabn_*() functions should be used for this type.</
P>return the hostname for the given address.
The lwres_gnba_*() functions should be used for this type.</
P>lwres_lwpacket_renderheader()</
TTtransfers the contents of lightweight resolver packet structure
in network byte order to the lightweight resolver buffer,
>lwres_lwpacket_parseheader()</
TTperforms the converse operation.
It transfers data in network byte order from buffer
The contents of the buffer
>Both functions have assertion checks to ensure that
>lwres_lwpacket_renderheader()</
TT>lwres_lwpacket_parseheader()</
TTIf there is insufficient space to copy data between the buffer
and lightweight resolver packet
>LWRES_R_UNEXPECTEDEND</
SPAN