external/bsd/bind/dist/lib/lwres/lwpacket.c

   1 /*      $NetBSD: lwpacket.c,v 1.4 2014/12/10 04:38:02 christos Exp $    */
   2
   3 /*
   4  * Copyright (C) 2004, 2005, 2007  Internet Systems Consortium, Inc. ("ISC")
   5  * Copyright (C) 2000, 2001  Internet Software Consortium.
   6  *
   7  * Permission to use, copy, modify, and/or distribute this software for any
   8  * purpose with or without fee is hereby granted, provided that the above
   9  * copyright notice and this permission notice appear in all copies.
  10  *
  11  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
  12  * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
  13  * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
  14  * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
  15  * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
  16  * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
  17  * PERFORMANCE OF THIS SOFTWARE.
  18  */
  19
  20 /* Id: lwpacket.c,v 1.18 2007/06/19 23:47:22 tbox Exp  */
  21
  22 /*! \file */
  23
  24 /**
  25  *    These functions rely on a struct lwres_lwpacket which is defined in
  26  *    \link lwpacket.h lwres/lwpacket.h.\endlink
  27  *
  28  *    The following opcodes are currently defined:
  29  *
  30  * \li   #LWRES_OPCODE_NOOP
  31  *           Success is always returned and the packet contents are
  32  *           echoed. The \link lwres_noop.c lwres_noop_*()\endlink functions should be used for this
  33  *           type.
  34  *
  35  * \li   #LWRES_OPCODE_GETADDRSBYNAME
  36  *           returns all known addresses for a given name. The
  37  *           \link lwres_gabn.c lwres_gabn_*()\endlink functions should be used for this type.
  38  *
  39  * \li   #LWRES_OPCODE_GETNAMEBYADDR
  40  *           return the hostname for the given address. The
  41  *           \link lwres_gnba.c lwres_gnba_*() \endlink functions should be used for this type.
  42  *
  43  *    lwres_lwpacket_renderheader() transfers the contents of lightweight
  44  *    resolver packet structure #lwres_lwpacket_t *pkt in network byte
  45  *    order to the lightweight resolver buffer, *b.
  46  *
  47  *    lwres_lwpacket_parseheader() performs the converse operation. It
  48  *    transfers data in network byte order from buffer *b to resolver
  49  *    packet *pkt. The contents of the buffer b should correspond to a
  50  *    #lwres_lwpacket_t.
  51  *
  52  * \section lwpacket_return Return Values
  53  *
  54  *    Successful calls to lwres_lwpacket_renderheader() and
  55  *    lwres_lwpacket_parseheader() return #LWRES_R_SUCCESS. If there is
  56  *    insufficient space to copy data between the buffer *b and
  57  *    lightweight resolver packet *pkt both functions return
  58  *    #LWRES_R_UNEXPECTEDEND.
  59  */
  60
  61 #include <config.h>
  62
  63 #include <assert.h>
  64 #include <stdlib.h>
  65 #include <string.h>
  66
  67 #include <lwres/lwbuffer.h>
  68 #include <lwres/lwpacket.h>
  69 #include <lwres/result.h>
  70
  71 #include "assert_p.h"
  72
  73 /*% Length of Packet */
  74 #define LWPACKET_LENGTH \
  75         (sizeof(lwres_uint16_t) * 4 + sizeof(lwres_uint32_t) * 5)
  76
  77 /*% transfers the contents of lightweight resolver packet structure lwres_lwpacket_t *pkt in network byte order to the lightweight resolver buffer, *b. */
  78
  79 lwres_result_t
  80 lwres_lwpacket_renderheader(lwres_buffer_t *b, lwres_lwpacket_t *pkt) {
  81         REQUIRE(b != NULL);
  82         REQUIRE(pkt != NULL);
  83
  84         if (!SPACE_OK(b, LWPACKET_LENGTH))
  85                 return (LWRES_R_UNEXPECTEDEND);
  86
  87         lwres_buffer_putuint32(b, pkt->length);
  88         lwres_buffer_putuint16(b, pkt->version);
  89         lwres_buffer_putuint16(b, pkt->pktflags);
  90         lwres_buffer_putuint32(b, pkt->serial);
  91         lwres_buffer_putuint32(b, pkt->opcode);
  92         lwres_buffer_putuint32(b, pkt->result);
  93         lwres_buffer_putuint32(b, pkt->recvlength);
  94         lwres_buffer_putuint16(b, pkt->authtype);
  95         lwres_buffer_putuint16(b, pkt->authlength);
  96
  97         return (LWRES_R_SUCCESS);
  98 }
  99
 100 /*% transfers data in network byte order from buffer *b to resolver packet *pkt. The contents of the buffer b should correspond to a lwres_lwpacket_t. */
 101
 102 lwres_result_t
 103 lwres_lwpacket_parseheader(lwres_buffer_t *b, lwres_lwpacket_t *pkt) {
 104         lwres_uint32_t space;
 105
 106         REQUIRE(b != NULL);
 107         REQUIRE(pkt != NULL);
 108
 109         space = LWRES_BUFFER_REMAINING(b);
 110         if (space < LWPACKET_LENGTH)
 111                 return (LWRES_R_UNEXPECTEDEND);
 112
 113         pkt->length = lwres_buffer_getuint32(b);
 114         /*
 115          * XXXBEW/MLG Checking that the buffer is long enough probably
 116          * shouldn't be done here, since this function is supposed to just
 117          * parse the header.
 118          */
 119         if (pkt->length > space)
 120                 return (LWRES_R_UNEXPECTEDEND);
 121         pkt->version = lwres_buffer_getuint16(b);
 122         pkt->pktflags = lwres_buffer_getuint16(b);
 123         pkt->serial = lwres_buffer_getuint32(b);
 124         pkt->opcode = lwres_buffer_getuint32(b);
 125         pkt->result = lwres_buffer_getuint32(b);
 126         pkt->recvlength = lwres_buffer_getuint32(b);
 127         pkt->authtype = lwres_buffer_getuint16(b);
 128         pkt->authlength = lwres_buffer_getuint16(b);
 129
 130         return (LWRES_R_SUCCESS);
 131 }