1 /* 2 * Copyright 1997-2002 Sun Microsystems, Inc. All rights reserved. 3 * Use is subject to license terms. 4 */ 5 6 /* 7 * Copyright (c) 1996-1999 by Internet Software Consortium. 8 * 9 * Permission to use, copy, modify, and distribute this software for any 10 * purpose with or without fee is hereby granted, provided that the above 11 * copyright notice and this permission notice appear in all copies. 12 * 13 * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS 14 * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES 15 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE 16 * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL 17 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR 18 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS 19 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS 20 * SOFTWARE. 21 */ 22 23 #pragma ident "%Z%%M% %I% %E% SMI" 24 25 #if defined(LIBC_SCCS) && !defined(lint) 26 static const char rcsid[] = "$Id: dns.c,v 1.16 2001/05/29 05:48:26 marka Exp $"; 27 #endif 28 29 /* 30 * dns.c --- this is the top-level accessor function for the dns 31 */ 32 33 #include "port_before.h" 34 35 #include <stdlib.h> 36 #include <string.h> 37 #include <errno.h> 38 39 #include <sys/types.h> 40 #include <netinet/in.h> 41 #include <arpa/nameser.h> 42 #include <resolv.h> 43 44 #include <resolv.h> 45 46 #include <isc/memcluster.h> 47 #include <irs.h> 48 49 #include "port_after.h" 50 51 #include "irs_p.h" 52 #include "hesiod.h" 53 #include "dns_p.h" 54 55 /* forward */ 56 57 static void dns_close(struct irs_acc *); 58 static struct __res_state * dns_res_get(struct irs_acc *); 59 static void dns_res_set(struct irs_acc *, struct __res_state *, 60 void (*)(void *)); 61 62 /* public */ 63 64 struct irs_acc * 65 irs_dns_acc(const char *options) { 66 struct irs_acc *acc; 67 struct dns_p *dns; 68 69 UNUSED(options); 70 71 if (!(acc = memget(sizeof *acc))) { 72 errno = ENOMEM; 73 return (NULL); 74 } 75 memset(acc, 0x5e, sizeof *acc); 76 if (!(dns = memget(sizeof *dns))) { 77 errno = ENOMEM; 78 memput(acc, sizeof *acc); 79 return (NULL); 80 } 81 memset(dns, 0x5e, sizeof *dns); 82 dns->res = NULL; 83 dns->free_res = NULL; 84 if (hesiod_init(&dns->hes_ctx) < 0) { 85 /* 86 * We allow the dns accessor class to initialize 87 * despite hesiod failing to initialize correctly, 88 * since dns host queries don't depend on hesiod. 89 */ 90 dns->hes_ctx = NULL; 91 } 92 acc->private = dns; 93 #ifdef WANT_IRS_GR 94 acc->gr_map = irs_dns_gr; 95 #else 96 acc->gr_map = NULL; 97 #endif 98 #ifdef WANT_IRS_PW 99 acc->pw_map = irs_dns_pw; 100 #else 101 acc->pw_map = NULL; 102 #endif 103 acc->sv_map = irs_dns_sv; 104 acc->pr_map = irs_dns_pr; 105 acc->ho_map = irs_dns_ho; 106 acc->nw_map = irs_dns_nw; 107 acc->ng_map = irs_nul_ng; 108 acc->res_get = dns_res_get; 109 acc->res_set = dns_res_set; 110 acc->close = dns_close; 111 return (acc); 112 } 113 114 /* methods */ 115 static struct __res_state * 116 dns_res_get(struct irs_acc *this) { 117 struct dns_p *dns = (struct dns_p *)this->private; 118 119 if (dns->res == NULL) { 120 struct __res_state *res; 121 res = (struct __res_state *)malloc(sizeof *res); 122 if (res == NULL) 123 return (NULL); 124 memset(dns->res, 0, sizeof *dns->res); 125 dns_res_set(this, res, free); 126 } 127 128 if ((dns->res->options & RES_INIT) == 0 && 129 res_ninit(dns->res) < 0) 130 return (NULL); 131 132 return (dns->res); 133 } 134 135 static void 136 dns_res_set(struct irs_acc *this, struct __res_state *res, 137 void (*free_res)(void *)) { 138 struct dns_p *dns = (struct dns_p *)this->private; 139 140 if (dns->res && dns->free_res) { 141 res_nclose(dns->res); 142 (*dns->free_res)(dns->res); 143 } 144 dns->res = res; 145 dns->free_res = free_res; 146 } 147 148 static void 149 dns_close(struct irs_acc *this) { 150 struct dns_p *dns; 151 152 dns = (struct dns_p *)this->private; 153 if (dns->res && dns->free_res) 154 (*dns->free_res)(dns->res); 155 if (dns->hes_ctx) 156 hesiod_end(dns->hes_ctx); 157 memput(dns, sizeof *dns); 158 memput(this, sizeof *this); 159 } 160 161