/* * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC") * Copyright (c) 1996-1999 by Internet Software Consortium. * * Permission to use, copy, modify, and distribute this software for any * purpose with or without fee is hereby granted, provided that the above * copyright notice and this permission notice appear in all copies. * * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ #if defined(LIBC_SCCS) && !defined(lint) static const char rcsid[] = "$Id: dns.c,v 1.5 2006/03/09 23:57:56 marka Exp $"; #endif /*! \file * \brief * dns.c --- this is the top-level accessor function for the dns */ #include "port_before.h" #include <stdlib.h> #include <string.h> #include <errno.h> #include <sys/types.h> #include <netinet/in.h> #include <arpa/nameser.h> #include <resolv.h> #include <resolv.h> #include <isc/memcluster.h> #include <irs.h> #include "port_after.h" #include "irs_p.h" #include "hesiod.h" #include "dns_p.h" /* forward */ static void dns_close(struct irs_acc *); static struct __res_state * dns_res_get(struct irs_acc *); static void dns_res_set(struct irs_acc *, struct __res_state *, void (*)(void *)); /* public */ struct irs_acc * irs_dns_acc(const char *options) { struct irs_acc *acc; struct dns_p *dns; UNUSED(options); if (!(acc = memget(sizeof *acc))) { errno = ENOMEM; return (NULL); } memset(acc, 0x5e, sizeof *acc); if (!(dns = memget(sizeof *dns))) { errno = ENOMEM; memput(acc, sizeof *acc); return (NULL); } memset(dns, 0x5e, sizeof *dns); dns->res = NULL; dns->free_res = NULL; if (hesiod_init(&dns->hes_ctx) < 0) { /* * We allow the dns accessor class to initialize * despite hesiod failing to initialize correctly, * since dns host queries don't depend on hesiod. */ dns->hes_ctx = NULL; } acc->private = dns; #ifdef WANT_IRS_GR acc->gr_map = irs_dns_gr; #else acc->gr_map = NULL; #endif #ifdef WANT_IRS_PW acc->pw_map = irs_dns_pw; #else acc->pw_map = NULL; #endif acc->sv_map = irs_dns_sv; acc->pr_map = irs_dns_pr; acc->ho_map = irs_dns_ho; acc->nw_map = irs_dns_nw; acc->ng_map = irs_nul_ng; acc->res_get = dns_res_get; acc->res_set = dns_res_set; acc->close = dns_close; return (acc); } /* methods */ static struct __res_state * dns_res_get(struct irs_acc *this) { struct dns_p *dns = (struct dns_p *)this->private; if (dns->res == NULL) { struct __res_state *res; res = (struct __res_state *)malloc(sizeof *res); if (res == NULL) return (NULL); memset(res, 0, sizeof *res); dns_res_set(this, res, free); } if ((dns->res->options & RES_INIT) == 0U && res_ninit(dns->res) < 0) return (NULL); return (dns->res); } static void dns_res_set(struct irs_acc *this, struct __res_state *res, void (*free_res)(void *)) { struct dns_p *dns = (struct dns_p *)this->private; if (dns->res && dns->free_res) { res_nclose(dns->res); (*dns->free_res)(dns->res); } dns->res = res; dns->free_res = free_res; } static void dns_close(struct irs_acc *this) { struct dns_p *dns; dns = (struct dns_p *)this->private; if (dns->res && dns->free_res) (*dns->free_res)(dns->res); if (dns->hes_ctx) hesiod_end(dns->hes_ctx); memput(dns, sizeof *dns); memput(this, sizeof *this); }