external/bsd/bind/dist/lib/lwres/man/lwres_gnba.3

   1 .\"     $NetBSD: lwres_gnba.3,v 1.5 2014/12/10 04:38:02 christos Exp $
   2 .\"
   3 .\" Copyright (C) 2004, 2005, 2007, 2014 Internet Systems Consortium, Inc. ("ISC")
   4 .\" Copyright (C) 2000, 2001 Internet Software Consortium.
   5 .\"
   6 .\" Permission to use, copy, modify, and/or distribute this software for any
   7 .\" purpose with or without fee is hereby granted, provided that the above
   8 .\" copyright notice and this permission notice appear in all copies.
   9 .\"
  10 .\" THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
  11 .\" REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
  12 .\" AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
  13 .\" INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
  14 .\" LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
  15 .\" OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
  16 .\" PERFORMANCE OF THIS SOFTWARE.
  17 .\"
  18 .\" Id
  19 .\"
  20 .hy 0
  21 .ad l
  22 .\"     Title: lwres_gnba
  23 .\"    Author:
  24 .\" Generator: DocBook XSL Stylesheets v1.71.1 <http://docbook.sf.net/>
  25 .\"      Date: June 18, 2007
  26 .\"    Manual: BIND9
  27 .\"    Source: BIND9
  28 .\"
  29 .TH "LWRES_GNBA" "3" "June 18, 2007" "BIND9" "BIND9"
  30 .\" disable hyphenation
  31 .nh
  32 .\" disable justification (adjust text to left margin only)
  33 .ad l
  34 .SH "NAME"
  35 lwres_gnbarequest_render, lwres_gnbaresponse_render, lwres_gnbarequest_parse, lwres_gnbaresponse_parse, lwres_gnbaresponse_free, lwres_gnbarequest_free \- lightweight resolver getnamebyaddress message handling
  36 .SH "SYNOPSIS"
  37 .nf
  38 #include <lwres/lwres.h>
  39 .fi
  40 .HP 40
  41 .BI "lwres_result_t lwres_gnbarequest_render(lwres_context_t\ *" "ctx" ", lwres_gnbarequest_t\ *" "req" ", lwres_lwpacket_t\ *" "pkt" ", lwres_buffer_t\ *" "b" ");"
  42 .HP 41
  43 .BI "lwres_result_t lwres_gnbaresponse_render(lwres_context_t\ *" "ctx" ", lwres_gnbaresponse_t\ *" "req" ", lwres_lwpacket_t\ *" "pkt" ", lwres_buffer_t\ *" "b" ");"
  44 .HP 39
  45 .BI "lwres_result_t lwres_gnbarequest_parse(lwres_context_t\ *" "ctx" ", lwres_buffer_t\ *" "b" ", lwres_lwpacket_t\ *" "pkt" ", lwres_gnbarequest_t\ **" "structp" ");"
  46 .HP 40
  47 .BI "lwres_result_t lwres_gnbaresponse_parse(lwres_context_t\ *" "ctx" ", lwres_buffer_t\ *" "b" ", lwres_lwpacket_t\ *" "pkt" ", lwres_gnbaresponse_t\ **" "structp" ");"
  48 .HP 29
  49 .BI "void lwres_gnbaresponse_free(lwres_context_t\ *" "ctx" ", lwres_gnbaresponse_t\ **" "structp" ");"
  50 .HP 28
  51 .BI "void lwres_gnbarequest_free(lwres_context_t\ *" "ctx" ", lwres_gnbarequest_t\ **" "structp" ");"
  52 .SH "DESCRIPTION"
  53 .PP
  54 These are low\-level routines for creating and parsing lightweight resolver address\-to\-name lookup request and response messages.
  55 .PP
  56 There are four main functions for the getnamebyaddr opcode. One render function converts a getnamebyaddr request structure \(em
  57 \fBlwres_gnbarequest_t\fR
  58 \(em to the lightweight resolver's canonical format. It is complemented by a parse function that converts a packet in this canonical format to a getnamebyaddr request structure. Another render function converts the getnamebyaddr response structure \(em
  59 \fBlwres_gnbaresponse_t\fR
  60 to the canonical format. This is complemented by a parse function which converts a packet in canonical format to a getnamebyaddr response structure.
  61 .PP
  62 These structures are defined in
  63 \fIlwres/lwres.h\fR. They are shown below.
  64 .PP
  65 .RS 4
  66 .nf
  67 #define LWRES_OPCODE_GETNAMEBYADDR      0x00010002U
  68 .fi
  69 .RE
  70 .sp
  71 .PP
  72 .RS 4
  73 .nf
  74 typedef struct {
  75         lwres_uint32_t  flags;
  76         lwres_addr_t    addr;
  77 } lwres_gnbarequest_t;
  78 .fi
  79 .RE
  80 .sp
  81 .PP
  82 .RS 4
  83 .nf
  84 typedef struct {
  85         lwres_uint32_t  flags;
  86         lwres_uint16_t  naliases;
  87         char           *realname;
  88         char          **aliases;
  89         lwres_uint16_t  realnamelen;
  90         lwres_uint16_t *aliaslen;
  91         void           *base;
  92         size_t          baselen;
  93 } lwres_gnbaresponse_t;
  94 .fi
  95 .RE
  96 .sp
  97 .PP
  98 \fBlwres_gnbarequest_render()\fR
  99 uses resolver context
 100 \fIctx\fR
 101 to convert getnamebyaddr request structure
 102 \fIreq\fR
 103 to canonical format. The packet header structure
 104 \fIpkt\fR
 105 is initialised and transferred to buffer
 106 \fIb\fR. The contents of
 107 \fI*req\fR
 108 are then appended to the buffer in canonical format.
 109 \fBlwres_gnbaresponse_render()\fR
 110 performs the same task, except it converts a getnamebyaddr response structure
 111 \fBlwres_gnbaresponse_t\fR
 112 to the lightweight resolver's canonical format.
 113 .PP
 114 \fBlwres_gnbarequest_parse()\fR
 115 uses context
 116 \fIctx\fR
 117 to convert the contents of packet
 118 \fIpkt\fR
 119 to a
 120 \fBlwres_gnbarequest_t\fR
 121 structure. Buffer
 122 \fIb\fR
 123 provides space to be used for storing this structure. When the function succeeds, the resulting
 124 \fBlwres_gnbarequest_t\fR
 125 is made available through
 126 \fI*structp\fR.
 127 \fBlwres_gnbaresponse_parse()\fR
 128 offers the same semantics as
 129 \fBlwres_gnbarequest_parse()\fR
 130 except it yields a
 131 \fBlwres_gnbaresponse_t\fR
 132 structure.
 133 .PP
 134 \fBlwres_gnbaresponse_free()\fR
 135 and
 136 \fBlwres_gnbarequest_free()\fR
 137 release the memory in resolver context
 138 \fIctx\fR
 139 that was allocated to the
 140 \fBlwres_gnbaresponse_t\fR
 141 or
 142 \fBlwres_gnbarequest_t\fR
 143 structures referenced via
 144 \fIstructp\fR. Any memory associated with ancillary buffers and strings for those structures is also discarded.
 145 .SH "RETURN VALUES"
 146 .PP
 147 The getnamebyaddr opcode functions
 148 \fBlwres_gnbarequest_render()\fR,
 149 \fBlwres_gnbaresponse_render()\fR
 150 \fBlwres_gnbarequest_parse()\fR
 151 and
 152 \fBlwres_gnbaresponse_parse()\fR
 153 all return
 154 \fBLWRES_R_SUCCESS\fR
 155 on success. They return
 156 \fBLWRES_R_NOMEMORY\fR
 157 if memory allocation fails.
 158 \fBLWRES_R_UNEXPECTEDEND\fR
 159 is returned if the available space in the buffer
 160 \fIb\fR
 161 is too small to accommodate the packet header or the
 162 \fBlwres_gnbarequest_t\fR
 163 and
 164 \fBlwres_gnbaresponse_t\fR
 165 structures.
 166 \fBlwres_gnbarequest_parse()\fR
 167 and
 168 \fBlwres_gnbaresponse_parse()\fR
 169 will return
 170 \fBLWRES_R_UNEXPECTEDEND\fR
 171 if the buffer is not empty after decoding the received packet. These functions will return
 172 \fBLWRES_R_FAILURE\fR
 173 if
 174 pktflags
 175 in the packet header structure
 176 \fBlwres_lwpacket_t\fR
 177 indicate that the packet is not a response to an earlier query.
 178 .SH "SEE ALSO"
 179 .PP
 180 \fBlwres_packet\fR(3).
 181 .SH "COPYRIGHT"
 182 Copyright \(co 2004, 2005, 2007, 2014 Internet Systems Consortium, Inc. ("ISC")
 183 .br
 184 Copyright \(co 2000, 2001 Internet Software Consortium.
 185 .br