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