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/*
** Copyright 1998 - 2011 Double Precision, Inc.
** See COPYING for distribution information.
*/
#include "rfc1035.h"
#include <string.h>
#include <errno.h>
static int ptr(struct rfc1035_res *, const void *, int,
void (*)(const char *, void *),
void *);
static void save_name(const char *name, void *void_arg)
{
strcpy((char *)void_arg, name);
}
int rfc1035_ptr(struct rfc1035_res *res, const RFC1035_ADDR *addr,
char *name)
{
return rfc1035_ptr_x(res, addr, save_name, name);
}
/* Convenient function to do reverse IP lookup */
#if RFC1035_IPV6
int rfc1035_ptr_x(struct rfc1035_res *res, const RFC1035_ADDR *addr,
void (*cb_func)(const char *, void *),
void *cb_arg)
{
struct in_addr in4;
if (IN6_IS_ADDR_V4MAPPED(addr))
{
rfc1035_ipv6to4(&in4, addr);
if (ptr(res, &in4, AF_INET, cb_func, cb_arg) == 0) return (0);
return (-1);
}
return (ptr(res, addr, AF_INET6, cb_func,cb_arg));
}
#else
int rfc1035_ptr_x(struct rfc1035_res *res, const RFC1035_ADDR *a,
void (*cb_func)(const char *, void *),
void *cb_arg)
{
return (ptr(res, a, AF_INET, cb_func, cb_arg));
}
#endif
static int ptr(struct rfc1035_res *res, const void *addr, int af,
void (*cb_func)(const char *, void *),
void *cb_arg)
{
struct rfc1035_reply *reply;
int n;
char name[256], ptrbuf[256];
#if RFC1035_IPV6
if (af == AF_INET6)
{
const char *sin6=(const char *)addr;
unsigned i;
*name=0;
for (i=sizeof(struct in6_addr); i; )
{
char buf[10];
--i;
sprintf(buf, "%x.%x.",
(int)(unsigned char)(sin6[i] & 0x0F),
(int)(unsigned char)((sin6[i] >> 4) & 0x0F));
strcat(name, buf);
}
strcat(name, "ip6.arpa");
}
else
#endif
if (af != AF_INET)
{
errno=ENOENT;
return (-1); /* hard error */
}
else
{
const char *p;
unsigned char a=0,b=0,c=0,d=0;
struct in_addr ia;
memcpy(&ia, addr, sizeof(ia));
rfc1035_ntoa_ipv4(&ia, name);
p=name;
while (*p >= '0' && *p <= '9')
a= (int)a * 10 + (*p++ - '0');
if (*p) p++;
while (*p >= '0' && *p <= '9')
b= (int)b * 10 + (*p++ - '0');
if (*p) p++;
while (*p >= '0' && *p <= '9')
c= (int)c * 10 + (*p++ - '0');
if (*p) p++;
while (*p >= '0' && *p <= '9')
d= (int)d * 10 + (*p++ - '0');
sprintf(name, "%d.%d.%d.%d.in-addr.arpa",
(int)d, (int)c, (int)b, (int)a);
}
if (rfc1035_resolve_cname(res, name,
RFC1035_TYPE_PTR, RFC1035_CLASS_IN, &reply, 0) < 0 ||
reply == 0 ||
(n=rfc1035_replysearch_an( res, reply, name, RFC1035_TYPE_PTR,
RFC1035_CLASS_IN, 0)) < 0 ||
rfc1035_replyhostname(reply, reply->allrrs[n]->rr.domainname,
ptrbuf) == 0)
{
if (reply && reply->rcode != RFC1035_RCODE_NXDOMAIN &&
reply->rcode != RFC1035_RCODE_NOERROR)
{
rfc1035_replyfree(reply);
errno=EAGAIN;
return (-1);
}
if (reply) rfc1035_replyfree(reply);
errno=ENOENT;
return (-1); /* hard error */
}
(*cb_func)(ptrbuf, cb_arg);
while ((n=rfc1035_replysearch_an(res, reply, name,
RFC1035_TYPE_PTR,
RFC1035_CLASS_IN, n+1)) >= 0)
{
if (rfc1035_replyhostname(reply,
reply->allrrs[n]->rr.domainname,
ptrbuf))
(*cb_func)(ptrbuf, cb_arg);
}
rfc1035_replyfree(reply);
return (0);
}
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