dns_pr.c revision 9525b14bcdeb5b5f6f95ab27c2f48f18bd2ec829
/*
* 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_pr.c,v 1.5 2005/04/27 04:56:22 sra Exp $";
#endif
/* Imports */
#include "port_before.h"
#include <sys/types.h>
#include <netinet/in.h>
#include <arpa/nameser.h>
#include <resolv.h>
#include <stdio.h>
#include <string.h>
#include <netdb.h>
#include <ctype.h>
#include <stdlib.h>
#include <errno.h>
#include <isc/memcluster.h>
#include <irs.h>
#include "port_after.h"
#include "irs_p.h"
#include "hesiod.h"
#include "dns_p.h"
/* Types. */
struct pvt {
struct dns_p * dns;
struct protoent proto;
char * prbuf;
};
/* Forward. */
static void pr_close(struct irs_pr *);
static struct protoent * pr_byname(struct irs_pr *, const char *);
static struct protoent * pr_bynumber(struct irs_pr *, int);
static struct protoent * pr_next(struct irs_pr *);
static void pr_rewind(struct irs_pr *);
static void pr_minimize(struct irs_pr *);
static struct __res_state * pr_res_get(struct irs_pr *);
static void pr_res_set(struct irs_pr *,
struct __res_state *,
void (*)(void *));
static struct protoent * parse_hes_list(struct irs_pr *, char **);
/* Public. */
struct irs_pr *
irs_dns_pr(struct irs_acc *this) {
struct dns_p *dns = (struct dns_p *)this->private;
struct pvt *pvt;
struct irs_pr *pr;
if (!dns->hes_ctx) {
errno = ENODEV;
return (NULL);
}
if (!(pvt = memget(sizeof *pvt))) {
errno = ENOMEM;
return (NULL);
}
memset(pvt, 0, sizeof *pvt);
if (!(pr = memget(sizeof *pr))) {
memput(pvt, sizeof *pvt);
errno = ENOMEM;
return (NULL);
}
memset(pr, 0x5e, sizeof *pr);
pvt->dns = dns;
pr->private = pvt;
pr->byname = pr_byname;
pr->bynumber = pr_bynumber;
pr->next = pr_next;
pr->rewind = pr_rewind;
pr->close = pr_close;
pr->minimize = pr_minimize;
pr->res_get = pr_res_get;
pr->res_set = pr_res_set;
return (pr);
}
/* Methods. */
static void
pr_close(struct irs_pr *this) {
struct pvt *pvt = (struct pvt *)this->private;
if (pvt->proto.p_aliases)
free(pvt->proto.p_aliases);
if (pvt->prbuf)
free(pvt->prbuf);
memput(pvt, sizeof *pvt);
memput(this, sizeof *this);
}
static struct protoent *
pr_byname(struct irs_pr *this, const char *name) {
struct pvt *pvt = (struct pvt *)this->private;
struct dns_p *dns = pvt->dns;
struct protoent *proto;
char **hes_list;
if (!(hes_list = hesiod_resolve(dns->hes_ctx, name, "protocol")))
return (NULL);
proto = parse_hes_list(this, hes_list);
hesiod_free_list(dns->hes_ctx, hes_list);
return (proto);
}
static struct protoent *
pr_bynumber(struct irs_pr *this, int num) {
struct pvt *pvt = (struct pvt *)this->private;
struct dns_p *dns = pvt->dns;
struct protoent *proto;
char numstr[16];
char **hes_list;
sprintf(numstr, "%d", num);
if (!(hes_list = hesiod_resolve(dns->hes_ctx, numstr, "protonum")))
return (NULL);
proto = parse_hes_list(this, hes_list);
hesiod_free_list(dns->hes_ctx, hes_list);
return (proto);
}
static struct protoent *
pr_next(struct irs_pr *this) {
UNUSED(this);
errno = ENODEV;
return (NULL);
}
static void
pr_rewind(struct irs_pr *this) {
UNUSED(this);
/* NOOP */
}
static void
pr_minimize(struct irs_pr *this) {
UNUSED(this);
/* NOOP */
}
static struct __res_state *
pr_res_get(struct irs_pr *this) {
struct pvt *pvt = (struct pvt *)this->private;
struct dns_p *dns = pvt->dns;
return (__hesiod_res_get(dns->hes_ctx));
}
static void
pr_res_set(struct irs_pr *this, struct __res_state * res,
void (*free_res)(void *)) {
struct pvt *pvt = (struct pvt *)this->private;
struct dns_p *dns = pvt->dns;
__hesiod_res_set(dns->hes_ctx, res, free_res);
}
/* Private. */
static struct protoent *
parse_hes_list(struct irs_pr *this, char **hes_list) {
struct pvt *pvt = (struct pvt *)this->private;
char *p, *cp, **cpp, **new;
int num = 0;
int max = 0;
for (cpp = hes_list; *cpp; cpp++) {
cp = *cpp;
/* Strip away comments, if any. */
if ((p = strchr(cp, '#')))
*p = 0;
/* Skip blank lines. */
p = cp;
while (*p && !isspace((unsigned char)*p))
p++;
if (!*p)
continue;
/* OK, we've got a live one. Let's parse it for real. */
if (pvt->prbuf)
free(pvt->prbuf);
pvt->prbuf = strdup(cp);
p = pvt->prbuf;
pvt->proto.p_name = p;
while (*p && !isspace((unsigned char)*p))
p++;
if (!*p)
continue;
*p++ = '\0';
pvt->proto.p_proto = atoi(p);
while (*p && !isspace((unsigned char)*p))
p++;
if (*p)
*p++ = '\0';
while (*p) {
if ((num + 1) >= max || !pvt->proto.p_aliases) {
max += 10;
new = realloc(pvt->proto.p_aliases,
max * sizeof(char *));
if (!new) {
errno = ENOMEM;
goto cleanup;
}
pvt->proto.p_aliases = new;
}
pvt->proto.p_aliases[num++] = p;
while (*p && !isspace((unsigned char)*p))
p++;
if (*p)
*p++ = '\0';
}
if (!pvt->proto.p_aliases)
pvt->proto.p_aliases = malloc(sizeof(char *));
if (!pvt->proto.p_aliases)
goto cleanup;
pvt->proto.p_aliases[num] = NULL;
return (&pvt->proto);
}
cleanup:
if (pvt->proto.p_aliases) {
free(pvt->proto.p_aliases);
pvt->proto.p_aliases = NULL;
}
if (pvt->prbuf) {
free(pvt->prbuf);
pvt->prbuf = NULL;
}
return (NULL);
}
/*! \file */