OpenBSD-4.6/usr.sbin/tcpdump/addrtoname.c
/* $OpenBSD: addrtoname.c,v 1.30 2007/10/07 16:41:05 deraadt Exp $ */
/*
* Copyright (c) 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that: (1) source code distributions
* retain the above copyright notice and this paragraph in its entirety, (2)
* distributions including binary code include the above copyright notice and
* this paragraph in its entirety in the documentation or other materials
* provided with the distribution, and (3) all advertising materials mentioning
* features or use of this software display the following acknowledgement:
* ``This product includes software developed by the University of California,
* Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
* the University nor the names of its contributors may be used to endorse
* or promote products derived from this software without specific prior
* written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*
* Internet, ethernet, port, and protocol string to address
* and address to string conversion routines
*/
#ifndef lint
static const char rcsid[] =
"@(#) $Id: addrtoname.c,v 1.30 2007/10/07 16:41:05 deraadt Exp $ (LBL)";
#endif
#include <sys/param.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <sys/types.h>
struct mbuf;
struct rtentry;
#include <net/if.h>
#include <netinet/in.h>
#include <netinet/if_ether.h>
#ifdef INET6
#include <netinet/ip6.h>
#endif
#include <arpa/inet.h>
#include <ctype.h>
#include <inttypes.h>
#include <netdb.h>
#include <pcap.h>
#include <pcap-namedb.h>
#ifdef HAVE_MEMORY_H
#include <memory.h>
#endif
#include <signal.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include "interface.h"
#include "addrtoname.h"
#include "llc.h"
#include "privsep.h"
#include "savestr.h"
/*
* hash tables for whatever-to-name translations
*/
#define HASHNAMESIZE 4096
struct hnamemem {
u_int32_t addr;
char *name;
struct hnamemem *nxt;
};
struct hnamemem hnametable[HASHNAMESIZE];
struct hnamemem tporttable[HASHNAMESIZE];
struct hnamemem uporttable[HASHNAMESIZE];
struct hnamemem eprototable[HASHNAMESIZE];
struct hnamemem dnaddrtable[HASHNAMESIZE];
struct hnamemem llcsaptable[HASHNAMESIZE];
#ifdef INET6
struct h6namemem {
struct in6_addr addr;
char *name;
struct h6namemem *nxt;
};
struct h6namemem h6nametable[HASHNAMESIZE];
#endif /* INET6 */
struct enamemem {
u_short e_addr0;
u_short e_addr1;
u_short e_addr2;
char *e_name;
u_char *e_nsap; /* used only for nsaptable[] */
#define e_bs e_nsap /* for bytestringtable */
struct enamemem *e_nxt;
};
struct enamemem enametable[HASHNAMESIZE];
struct enamemem nsaptable[HASHNAMESIZE];
struct enamemem bytestringtable[HASHNAMESIZE];
static char *ipprototable[256];
struct protoidmem {
u_int32_t p_oui;
u_short p_proto;
char *p_name;
struct protoidmem *p_nxt;
};
struct protoidmem protoidtable[HASHNAMESIZE];
/*
* A faster replacement for inet_ntoa().
*/
char *
intoa(u_int32_t addr)
{
register char *cp;
register u_int byte;
register int n;
static char buf[sizeof(".xxx.xxx.xxx.xxx")];
NTOHL(addr);
cp = &buf[sizeof buf];
*--cp = '\0';
n = 4;
do {
byte = addr & 0xff;
*--cp = byte % 10 + '0';
byte /= 10;
if (byte > 0) {
*--cp = byte % 10 + '0';
byte /= 10;
if (byte > 0)
*--cp = byte + '0';
}
*--cp = '.';
addr >>= 8;
} while (--n > 0);
return cp + 1;
}
static u_int32_t f_netmask;
static u_int32_t f_localnet;
static u_int32_t netmask;
/*
* Return a name for the IP address pointed to by ap. This address
* is assumed to be in network byte order.
*/
char *
getname(const u_char *ap)
{
char host[MAXHOSTNAMELEN];
u_int32_t addr;
struct hnamemem *p;
/*
* Extract 32 bits in network order, dealing with alignment.
*/
switch ((intptr_t)ap & (sizeof(u_int32_t)-1)) {
case 0:
addr = *(u_int32_t *)ap;
break;
case 2:
#if BYTE_ORDER == BIG_ENDIAN
addr = ((u_int32_t)*(u_short *)ap << 16) |
(u_int32_t)*(u_short *)(ap + 2);
#else
addr = ((u_int32_t)*(u_short *)(ap + 2) << 16) |
(u_int32_t)*(u_short *)ap;
#endif
break;
default:
#if BYTE_ORDER == BIG_ENDIAN
addr = ((u_int32_t)ap[0] << 24) |
((u_int32_t)ap[1] << 16) |
((u_int32_t)ap[2] << 8) |
(u_int32_t)ap[3];
#else
addr = ((u_int32_t)ap[3] << 24) |
((u_int32_t)ap[2] << 16) |
((u_int32_t)ap[1] << 8) |
(u_int32_t)ap[0];
#endif
break;
}
p = &hnametable[addr & (HASHNAMESIZE-1)];
for (; p->nxt; p = p->nxt) {
if (p->addr == addr)
return (p->name);
}
p->addr = addr;
p->nxt = newhnamemem();
/*
* Only print names when:
* (1) -n was not given
* (2) Address is foreign and -f was given. (If -f was not
* give, f_netmask and f_local are 0 and the test
* evaluates to true)
* (3) -a was given or the host portion is not all ones
* nor all zeros (i.e. not a network or broadcast address)
*/
if (!nflag &&
(addr & f_netmask) == f_localnet &&
(aflag ||
!((addr & ~netmask) == 0 || (addr | netmask) == 0xffffffff))) {
size_t n = priv_gethostbyaddr((char *)&addr, sizeof(addr),
AF_INET, host, sizeof(host));
if (n > 0) {
char *dotp;
p->name = savestr(host);
if (Nflag) {
/* Remove domain qualifications */
dotp = strchr(p->name, '.');
if (dotp)
*dotp = '\0';
}
return (p->name);
}
}
p->name = savestr(intoa(addr));
return (p->name);
}
#ifdef INET6
/*
* Return a name for the IP6 address pointed to by ap. This address
* is assumed to be in network byte order.
*/
char *
getname6(const u_char *ap)
{
char host[MAXHOSTNAMELEN];
struct in6_addr addr;
struct h6namemem *p;
register char *cp;
char ntop_buf[INET6_ADDRSTRLEN];
memcpy(&addr, ap, sizeof(addr));
p = &h6nametable[*(u_int16_t *)&addr.s6_addr[14] & (HASHNAMESIZE-1)];
for (; p->nxt; p = p->nxt) {
if (memcmp(&p->addr, &addr, sizeof(addr)) == 0)
return (p->name);
}
p->addr = addr;
p->nxt = newh6namemem();
/*
* Only print names when:
* (1) -n was not given
* (2) Address is foreign and -f was given. (If -f was not
* give, f_netmask and f_local are 0 and the test
* evaluates to true)
* (3) -a was given or the host portion is not all ones
* nor all zeros (i.e. not a network or broadcast address)
*/
if (!nflag
#if 0
&&
(addr & f_netmask) == f_localnet &&
(aflag ||
!((addr & ~netmask) == 0 || (addr | netmask) == 0xffffffff))
#endif
) {
size_t n = priv_gethostbyaddr((char *)&addr, sizeof(addr),
AF_INET6, host, sizeof(host));
if (n > 0) {
char *dotp;
p->name = savestr(host);
if (Nflag) {
/* Remove domain qualifications */
dotp = strchr(p->name, '.');
if (dotp)
*dotp = '\0';
}
return (p->name);
}
}
cp = (char *)inet_ntop(AF_INET6, &addr, ntop_buf, sizeof(ntop_buf));
p->name = savestr(cp);
return (p->name);
}
#endif /* INET6 */
static char hex[] = "0123456789abcdef";
/* Find the hash node that corresponds the ether address 'ep' */
static inline struct enamemem *
lookup_emem(const u_char *ep)
{
register u_int i, j, k;
struct enamemem *tp;
k = (ep[0] << 8) | ep[1];
j = (ep[2] << 8) | ep[3];
i = (ep[4] << 8) | ep[5];
tp = &enametable[(i ^ j) & (HASHNAMESIZE-1)];
while (tp->e_nxt)
if (tp->e_addr0 == i &&
tp->e_addr1 == j &&
tp->e_addr2 == k)
return tp;
else
tp = tp->e_nxt;
tp->e_addr0 = i;
tp->e_addr1 = j;
tp->e_addr2 = k;
tp->e_nxt = (struct enamemem *)calloc(1, sizeof(*tp));
if (tp->e_nxt == NULL)
error("lookup_emem: calloc");
return tp;
}
/*
* Find the hash node that corresponds to the bytestring 'bs'
* with length 'nlen'
*/
static inline struct enamemem *
lookup_bytestring(register const u_char *bs, const int nlen)
{
struct enamemem *tp;
register u_int i, j, k;
if (nlen >= 6) {
k = (bs[0] << 8) | bs[1];
j = (bs[2] << 8) | bs[3];
i = (bs[4] << 8) | bs[5];
} else if (nlen >= 4) {
k = (bs[0] << 8) | bs[1];
j = (bs[2] << 8) | bs[3];
i = 0;
} else
i = j = k = 0;
tp = &bytestringtable[(i ^ j) & (HASHNAMESIZE-1)];
while (tp->e_nxt)
if (tp->e_addr0 == i &&
tp->e_addr1 == j &&
tp->e_addr2 == k &&
bcmp((char *)bs, (char *)(tp->e_bs), nlen) == 0)
return tp;
else
tp = tp->e_nxt;
tp->e_addr0 = i;
tp->e_addr1 = j;
tp->e_addr2 = k;
tp->e_bs = (u_char *) calloc(1, nlen + 1);
if (tp->e_bs == NULL)
error("lookup_bytestring: calloc");
bcopy(bs, tp->e_bs, nlen);
tp->e_nxt = (struct enamemem *)calloc(1, sizeof(*tp));
if (tp->e_nxt == NULL)
error("lookup_bytestring: calloc");
return tp;
}
/* Find the hash node that corresponds the NSAP 'nsap' */
static inline struct enamemem *
lookup_nsap(register const u_char *nsap)
{
register u_int i, j, k;
int nlen = *nsap;
struct enamemem *tp;
const u_char *ensap = nsap + nlen - 6;
if (nlen > 6) {
k = (ensap[0] << 8) | ensap[1];
j = (ensap[2] << 8) | ensap[3];
i = (ensap[4] << 8) | ensap[5];
}
else
i = j = k = 0;
tp = &nsaptable[(i ^ j) & (HASHNAMESIZE-1)];
while (tp->e_nxt)
if (tp->e_addr0 == i &&
tp->e_addr1 == j &&
tp->e_addr2 == k &&
tp->e_nsap[0] == nlen &&
memcmp((char *)&(nsap[1]),
(char *)&(tp->e_nsap[1]), nlen) == 0)
return tp;
else
tp = tp->e_nxt;
tp->e_addr0 = i;
tp->e_addr1 = j;
tp->e_addr2 = k;
tp->e_nsap = (u_char *)malloc(nlen + 1);
if (tp->e_nsap == NULL)
error("lookup_nsap: malloc");
memcpy((char *)tp->e_nsap, (char *)nsap, nlen + 1);
tp->e_nxt = (struct enamemem *)calloc(1, sizeof(*tp));
if (tp->e_nxt == NULL)
error("lookup_nsap: calloc");
return tp;
}
/* Find the hash node that corresponds the protoid 'pi'. */
static inline struct protoidmem *
lookup_protoid(const u_char *pi)
{
register u_int i, j;
struct protoidmem *tp;
/* 5 octets won't be aligned */
i = (((pi[0] << 8) + pi[1]) << 8) + pi[2];
j = (pi[3] << 8) + pi[4];
/* XXX should be endian-insensitive, but do big-endian testing XXX */
tp = &protoidtable[(i ^ j) & (HASHNAMESIZE-1)];
while (tp->p_nxt)
if (tp->p_oui == i && tp->p_proto == j)
return tp;
else
tp = tp->p_nxt;
tp->p_oui = i;
tp->p_proto = j;
tp->p_nxt = (struct protoidmem *)calloc(1, sizeof(*tp));
if (tp->p_nxt == NULL)
error("lookup_protoid: calloc");
return tp;
}
char *
etheraddr_string(register const u_char *ep)
{
register struct enamemem *tp;
struct ether_addr e;
tp = lookup_emem(ep);
if (tp->e_name)
return (tp->e_name);
#ifdef HAVE_ETHER_NTOHOST
if (!nflag) {
char buf[MAXHOSTNAMELEN + 1];
if (priv_ether_ntohost(buf, sizeof(buf),
(struct ether_addr *)ep) > 0) {
tp->e_name = savestr(buf);
return (tp->e_name);
}
}
#endif
memcpy(e.ether_addr_octet, ep, sizeof(e.ether_addr_octet));
tp->e_name = savestr(ether_ntoa(&e));
return (tp->e_name);
}
char *
linkaddr_string(const u_char *ep, const int len)
{
register u_int i, j;
register char *cp;
register struct enamemem *tp;
if (len == 6) /* XXX not totally correct... */
return etheraddr_string(ep);
tp = lookup_bytestring(ep, len);
if (tp->e_name)
return (tp->e_name);
tp->e_name = cp = (char *)malloc(len*3);
if (tp->e_name == NULL)
error("linkaddr_string: malloc");
if ((j = *ep >> 4) != 0)
*cp++ = hex[j];
*cp++ = hex[*ep++ & 0xf];
for (i = len-1; i > 0 ; --i) {
*cp++ = ':';
if ((j = *ep >> 4) != 0)
*cp++ = hex[j];
*cp++ = hex[*ep++ & 0xf];
}
*cp = '\0';
return (tp->e_name);
}
char *
etherproto_string(u_short port)
{
register char *cp;
register struct hnamemem *tp;
register u_int32_t i = port;
char buf[sizeof("0000")];
for (tp = &eprototable[i & (HASHNAMESIZE-1)]; tp->nxt; tp = tp->nxt)
if (tp->addr == i)
return (tp->name);
tp->addr = i;
tp->nxt = newhnamemem();
cp = buf;
NTOHS(port);
*cp++ = hex[port >> 12 & 0xf];
*cp++ = hex[port >> 8 & 0xf];
*cp++ = hex[port >> 4 & 0xf];
*cp++ = hex[port & 0xf];
*cp++ = '\0';
tp->name = savestr(buf);
return (tp->name);
}
char *
protoid_string(register const u_char *pi)
{
register u_int i, j;
register char *cp;
register struct protoidmem *tp;
char buf[sizeof("00:00:00:00:00")];
tp = lookup_protoid(pi);
if (tp->p_name)
return tp->p_name;
cp = buf;
if ((j = *pi >> 4) != 0)
*cp++ = hex[j];
*cp++ = hex[*pi++ & 0xf];
for (i = 4; (int)--i >= 0;) {
*cp++ = ':';
if ((j = *pi >> 4) != 0)
*cp++ = hex[j];
*cp++ = hex[*pi++ & 0xf];
}
*cp = '\0';
tp->p_name = savestr(buf);
return (tp->p_name);
}
char *
llcsap_string(u_char sap)
{
register struct hnamemem *tp;
register u_int32_t i = sap;
char buf[sizeof("sap 00")];
for (tp = &llcsaptable[i & (HASHNAMESIZE-1)]; tp->nxt; tp = tp->nxt)
if (tp->addr == i)
return (tp->name);
tp->addr = i;
tp->nxt = newhnamemem();
snprintf(buf, sizeof(buf), "sap %02x", sap & 0xff);
tp->name = savestr(buf);
return (tp->name);
}
char *
isonsap_string(const u_char *nsap)
{
register u_int i, nlen = nsap[0];
register char *cp;
register struct enamemem *tp;
tp = lookup_nsap(nsap);
if (tp->e_name)
return tp->e_name;
tp->e_name = cp = (char *)malloc(nlen * 2 + 2);
if (cp == NULL)
error("isonsap_string: malloc");
nsap++;
*cp++ = '/';
for (i = nlen; (int)--i >= 0;) {
*cp++ = hex[*nsap >> 4];
*cp++ = hex[*nsap++ & 0xf];
}
*cp = '\0';
return (tp->e_name);
}
char *
tcpport_string(u_short port)
{
register struct hnamemem *tp;
register u_int32_t i = port;
char buf[sizeof("00000")];
for (tp = &tporttable[i & (HASHNAMESIZE-1)]; tp->nxt; tp = tp->nxt)
if (tp->addr == i)
return (tp->name);
tp->addr = i;
tp->nxt = newhnamemem();
(void)snprintf(buf, sizeof(buf), "%u", i);
tp->name = savestr(buf);
return (tp->name);
}
char *
udpport_string(register u_short port)
{
register struct hnamemem *tp;
register u_int32_t i = port;
char buf[sizeof("00000")];
for (tp = &uporttable[i & (HASHNAMESIZE-1)]; tp->nxt; tp = tp->nxt)
if (tp->addr == i)
return (tp->name);
tp->addr = i;
tp->nxt = newhnamemem();
(void)snprintf(buf, sizeof(buf), "%u", i);
tp->name = savestr(buf);
return (tp->name);
}
char *
ipproto_string(u_int proto)
{
return ipprototable[proto & 0xff];
}
static void
init_servarray(void)
{
struct hnamemem *table;
int i, port;
char buf[sizeof("0000000000")];
char service[BUFSIZ];
char protocol[BUFSIZ];
priv_getserventries();
while (priv_getserventry(service, sizeof(service), &port, protocol,
sizeof(protocol)) != 0) {
port = ntohs(port);
i = port & (HASHNAMESIZE-1);
if (strcmp(protocol, "tcp") == 0)
table = &tporttable[i];
else if (strcmp(protocol, "udp") == 0)
table = &uporttable[i];
else
continue;
while (table->name)
table = table->nxt;
if (nflag) {
(void)snprintf(buf, sizeof(buf), "%d", port);
table->name = savestr(buf);
} else
table->name = savestr(service);
table->addr = port;
table->nxt = newhnamemem();
}
}
static void
init_ipprotoarray(void)
{
int i;
char buf[sizeof("000")];
char prot[BUFSIZ];
if (!nflag) {
priv_getprotoentries();
while (priv_getprotoentry(prot, sizeof(prot), &i) != 0)
ipprototable[i & 0xff] = savestr(prot);
}
for (i = 0; i < 256; i++)
if (ipprototable[i] == NULL) {
(void)snprintf(buf, sizeof(buf), "%d", i);
ipprototable[i] = savestr(buf);
}
}
/*XXX from libbpfc.a */
extern struct eproto {
char *s;
u_short p;
} eproto_db[];
static void
init_eprotoarray(void)
{
register int i;
register struct hnamemem *table;
for (i = 0; eproto_db[i].s; i++) {
int j = ntohs(eproto_db[i].p) & (HASHNAMESIZE-1);
table = &eprototable[j];
while (table->name)
table = table->nxt;
table->name = eproto_db[i].s;
table->addr = ntohs(eproto_db[i].p);
table->nxt = newhnamemem();
}
}
/*
* SNAP proto IDs with org code 0:0:0 are actually encapsulated Ethernet
* types.
*/
static void
init_protoidarray(void)
{
register int i;
register struct protoidmem *tp;
u_char protoid[5];
protoid[0] = 0;
protoid[1] = 0;
protoid[2] = 0;
for (i = 0; eproto_db[i].s; i++) {
u_short etype = htons(eproto_db[i].p);
memcpy((char *)&protoid[3], (char *)&etype, 2);
tp = lookup_protoid(protoid);
tp->p_name = savestr(eproto_db[i].s);
}
}
static struct etherlist {
u_char addr[6];
char *name;
} etherlist[] = {
{{ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }, "Broadcast" },
{{ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }, NULL }
};
/*
* Initialize the ethers hash table. We take two different approaches
* depending on whether or not the system provides the ethers name
* service. If it does, we just wire in a few names at startup,
* and etheraddr_string() fills in the table on demand. If it doesn't,
* then we suck in the entire /etc/ethers file at startup. The idea
* is that parsing the local file will be fast, but spinning through
* all the ethers entries via NIS & next_etherent might be very slow.
*
* XXX pcap_next_etherent doesn't belong in the pcap interface, but
* since the pcap module already does name-to-address translation,
* it's already does most of the work for the ethernet address-to-name
* translation, so we just pcap_next_etherent as a convenience.
*/
static void
init_etherarray(void)
{
register struct etherlist *el;
register struct enamemem *tp;
#ifdef HAVE_ETHER_NTOHOST
char name[MAXHOSTNAMELEN + 1];
#else
register struct pcap_etherent *ep;
register FILE *fp;
/* Suck in entire ethers file */
fp = fopen(PCAP_ETHERS_FILE, "r");
if (fp != NULL) {
while ((ep = pcap_next_etherent(fp)) != NULL) {
tp = lookup_emem(ep->addr);
tp->e_name = savestr(ep->name);
}
(void)fclose(fp);
}
#endif
/* Hardwire some ethernet names */
for (el = etherlist; el->name != NULL; ++el) {
tp = lookup_emem(el->addr);
/* Don't override existing name */
if (tp->e_name != NULL)
continue;
#ifdef HAVE_ETHER_NTOHOST
/* Use yp/nis version of name if available */
if (priv_ether_ntohost(name, sizeof(name),
(struct ether_addr *)el->addr) > 0) {
tp->e_name = savestr(name);
continue;
}
#endif
tp->e_name = el->name;
}
}
static struct tok llcsap_db[] = {
{ LLCSAP_NULL, "null" },
{ LLCSAP_8021B_I, "802.1b-gsap" },
{ LLCSAP_8021B_G, "802.1b-isap" },
{ LLCSAP_IP, "ip-sap" },
{ LLCSAP_PROWAYNM, "proway-nm" },
{ LLCSAP_8021D, "802.1d" },
{ LLCSAP_RS511, "eia-rs511" },
{ LLCSAP_ISO8208, "x.25/llc2" },
{ LLCSAP_PROWAY, "proway" },
{ LLCSAP_ISONS, "iso-clns" },
{ LLCSAP_GLOBAL, "global" },
{ 0, NULL }
};
static void
init_llcsaparray(void)
{
register int i;
register struct hnamemem *table;
for (i = 0; llcsap_db[i].s != NULL; i++) {
table = &llcsaptable[llcsap_db[i].v];
while (table->name)
table = table->nxt;
table->name = llcsap_db[i].s;
table->addr = llcsap_db[i].v;
table->nxt = newhnamemem();
}
}
/*
* Initialize the address to name translation machinery. We map all
* non-local IP addresses to numeric addresses if fflag is true (i.e.,
* to prevent blocking on the nameserver). localnet is the IP address
* of the local network. mask is its subnet mask.
*/
void
init_addrtoname(u_int32_t localnet, u_int32_t mask)
{
netmask = mask;
if (fflag) {
f_localnet = localnet;
f_netmask = mask;
}
init_servarray();
init_ipprotoarray();
if (nflag)
/*
* Simplest way to suppress names.
*/
return;
init_etherarray();
init_eprotoarray();
init_llcsaparray();
init_protoidarray();
}
char *
dnaddr_string(u_short dnaddr)
{
register struct hnamemem *tp;
for (tp = &dnaddrtable[dnaddr & (HASHNAMESIZE-1)]; tp->nxt != 0;
tp = tp->nxt)
if (tp->addr == dnaddr)
return (tp->name);
tp->addr = dnaddr;
tp->nxt = newhnamemem();
if (nflag)
tp->name = dnnum_string(dnaddr);
else
tp->name = dnname_string(dnaddr);
return(tp->name);
}
/* Return a zero'ed hnamemem struct and cuts down on calloc() overhead */
struct hnamemem *
newhnamemem(void)
{
register struct hnamemem *p;
static struct hnamemem *ptr = NULL;
static u_int num = 0;
if (num <= 0) {
num = 64;
ptr = (struct hnamemem *)calloc(num, sizeof (*ptr));
if (ptr == NULL)
error("newhnamemem: calloc");
}
--num;
p = ptr++;
return (p);
}
#ifdef INET6
/* Return a zero'ed h6namemem struct and cuts down on calloc() overhead */
struct h6namemem *
newh6namemem(void)
{
register struct h6namemem *p;
static struct h6namemem *ptr = NULL;
static u_int num = 0;
if (num <= 0) {
num = 64;
ptr = (struct h6namemem *)calloc(num, sizeof (*ptr));
if (ptr == NULL)
error("newh6namemem: calloc");
}
--num;
p = ptr++;
return (p);
}
#endif /* INET6 */