1/* $NetBSD$ */ 2 3/* 4 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC") 5 * Copyright (c) 1996-1999 by Internet Software Consortium. 6 * 7 * Permission to use, copy, modify, and 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 12 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 13 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR 14 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 15 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 16 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT 17 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 18 */ 19 20#if defined(LIBC_SCCS) && !defined(lint) 21static const char rcsid[] = "Id: dns.c,v 1.5 2006/03/09 23:57:56 marka Exp "; 22#endif 23 24/*! \file 25 * \brief 26 * dns.c --- this is the top-level accessor function for the dns 27 */ 28 29#include "port_before.h" 30 31#include <stdlib.h> 32#include <string.h> 33#include <errno.h> 34 35#include <sys/types.h> 36#include <netinet/in.h> 37#include <arpa/nameser.h> 38#include <resolv.h> 39 40#include <resolv.h> 41 42#include <isc/memcluster.h> 43#include <irs.h> 44 45#include "port_after.h" 46 47#include "irs_p.h" 48#include "hesiod.h" 49#include "dns_p.h" 50 51/* forward */ 52 53static void dns_close(struct irs_acc *); 54static struct __res_state * dns_res_get(struct irs_acc *); 55static void dns_res_set(struct irs_acc *, struct __res_state *, 56 void (*)(void *)); 57 58/* public */ 59 60struct irs_acc * 61irs_dns_acc(const char *options) { 62 struct irs_acc *acc; 63 struct dns_p *dns; 64 65 UNUSED(options); 66 67 if (!(acc = memget(sizeof *acc))) { 68 errno = ENOMEM; 69 return (NULL); 70 } 71 memset(acc, 0x5e, sizeof *acc); 72 if (!(dns = memget(sizeof *dns))) { 73 errno = ENOMEM; 74 memput(acc, sizeof *acc); 75 return (NULL); 76 } 77 memset(dns, 0x5e, sizeof *dns); 78 dns->res = NULL; 79 dns->free_res = NULL; 80 if (hesiod_init(&dns->hes_ctx) < 0) { 81 /* 82 * We allow the dns accessor class to initialize 83 * despite hesiod failing to initialize correctly, 84 * since dns host queries don't depend on hesiod. 85 */ 86 dns->hes_ctx = NULL; 87 } 88 acc->private = dns; 89#ifdef WANT_IRS_GR 90 acc->gr_map = irs_dns_gr; 91#else 92 acc->gr_map = NULL; 93#endif 94#ifdef WANT_IRS_PW 95 acc->pw_map = irs_dns_pw; 96#else 97 acc->pw_map = NULL; 98#endif 99 acc->sv_map = irs_dns_sv; 100 acc->pr_map = irs_dns_pr; 101 acc->ho_map = irs_dns_ho; 102 acc->nw_map = irs_dns_nw; 103 acc->ng_map = irs_nul_ng; 104 acc->res_get = dns_res_get; 105 acc->res_set = dns_res_set; 106 acc->close = dns_close; 107 return (acc); 108} 109 110/* methods */ 111static struct __res_state * 112dns_res_get(struct irs_acc *this) { 113 struct dns_p *dns = (struct dns_p *)this->private; 114 115 if (dns->res == NULL) { 116 struct __res_state *res; 117 res = (struct __res_state *)malloc(sizeof *res); 118 if (res == NULL) 119 return (NULL); 120 memset(res, 0, sizeof *res); 121 dns_res_set(this, res, free); 122 } 123 124 if ((dns->res->options & RES_INIT) == 0U && 125 res_ninit(dns->res) < 0) 126 return (NULL); 127 128 return (dns->res); 129} 130 131static void 132dns_res_set(struct irs_acc *this, struct __res_state *res, 133 void (*free_res)(void *)) { 134 struct dns_p *dns = (struct dns_p *)this->private; 135 136 if (dns->res && dns->free_res) { 137 res_nclose(dns->res); 138 (*dns->free_res)(dns->res); 139 } 140 dns->res = res; 141 dns->free_res = free_res; 142} 143 144static void 145dns_close(struct irs_acc *this) { 146 struct dns_p *dns; 147 148 dns = (struct dns_p *)this->private; 149 if (dns->res && dns->free_res) 150 (*dns->free_res)(dns->res); 151 if (dns->hes_ctx) 152 hesiod_end(dns->hes_ctx); 153 memput(dns, sizeof *dns); 154 memput(this, sizeof *this); 155} 156 157