addrtoname.c

Windump3.6.2源代码

/*
 * 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[] =
    "@(#) $Header: /tcpdump/master/tcpdump/addrtoname.c,v 1.69.2.1 2001/01/17 18:29:58 guy Exp $ (LBL)";
#endif

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <sys/types.h>

#ifndef WIN32
#include <sys/socket.h>
#include <sys/time.h>
#else
#include <winsock2.h>
#include "bittypes.h"
#ifdef HAVE_ADDRINFO
#include <ws2tcpip.h>
#include <tpipv6.h> 
#else
/* in6_addr is already defined in ws2tcpip.h */
struct in6_addr {
		u_char	s6_addr[16];	/* IPv6 address */
};
#endif /* HAVE_ADDRINFO */

#define INET6_ADDRSTRLEN 46
#include "missing/bittypes.h"

#ifdef HAVE_ADDRINFO
/*
 * only member h_name of struct hostent is valid.
 */
static struct hostent * w32gethostbyaddr(const char * addr, int len, int type)
{
  static struct hostent host;
  static char hostbuf[NI_MAXHOST];
  char hname[NI_MAXHOST];
  struct sockaddr_in6 addr6;

  host.h_name = hostbuf;
  switch (type) {
  case AF_INET:
    return gethostbyaddr(addr, len, type);
    break;
  case AF_INET6:
    memset(&addr6, 0, sizeof(addr6));
    addr6.sin6_family = AF_INET6;
    memcpy(&addr6.sin6_addr, addr, len);
    if (getnameinfo((struct sockaddr *)&addr6, sizeof(addr6),
		    hname, sizeof(hname),
		    NULL, 0,
		    0)) {
      return NULL;
    } else {
      strcpy(host.h_name, hname);
      return &host;
    }
    break;
  default:
    return NULL;
  }
}
#endif /* HAVE_ADDRINFO */
#endif /* WIN32 */

struct mbuf;
struct rtentry;
#ifndef WIN32
#include <net/if.h>

#include <netinet/in.h>
#endif
#ifdef HAVE_NETINET_IF_ETHER_H
#include <netinet/if_ether.h>
#endif

#ifndef WIN32
#include <arpa/inet.h>
#endif

#include <ctype.h>
#include <netdb.h>
#include <pcap.h>
#include <pcap-namedb.h>
#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 "savestr.h"
#include "setsignal.h"

/* Forwards */
static RETSIGTYPE nohostname(int);

/*
 * 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[] */
	struct enamemem *e_nxt;
};

struct enamemem enametable[HASHNAMESIZE];
struct enamemem nsaptable[HASHNAMESIZE];

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;

/*
 * "getname" is written in this atrocious way to make sure we don't
 * wait forever while trying to get hostnames from yp.
 */
#include <setjmp.h>

jmp_buf getname_env;

static RETSIGTYPE
nohostname(int signo)
{
	longjmp(getname_env, 1);
}

/*
 * 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)
{
	register struct hostent *hp;
	u_int32_t addr;
	static struct hnamemem *p;		/* static for longjmp() */

#ifndef LBL_ALIGN
	addr = *(const u_int32_t *)ap;
#else
	memcpy(&addr, ap, sizeof(addr));
#endif
	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))) {
		if (!setjmp(getname_env)) {
#ifndef WIN32
			(void)setsignal(SIGALRM, nohostname);
			(void)alarm(20);
			hp = gethostbyaddr((char *)&addr, 4, AF_INET);
			(void)alarm(0);
#else
			// In Win32 there is no alarm
			hp = gethostbyaddr((char *)&addr, 4, AF_INET);
#endif
			if (hp) {
				char *dotp;

				p->name = savestr(hp->h_name);
				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)
{
	register struct hostent *hp;
	struct in6_addr addr;
	static struct h6namemem *p;		/* static for longjmp() */
	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
	    ) {
		if (!setjmp(getname_env)) {
#ifndef WIN32
			(void)setsignal(SIGALRM, nohostname);
			(void)alarm(20);
			hp = gethostbyaddr((char *)&addr, sizeof(addr), AF_INET6);
			(void)alarm(0);
#else
			// In Win32 there is no alarm
#ifdef __MINGW32__
			hp = gethostbyaddr((char *)&addr, 4, AF_INET);
#else
			hp = w32gethostbyaddr((char *)&addr, sizeof(addr), AF_INET6);
#endif /* __MINGW32__ */
#endif /* Win32 */
			if (hp) {
				char *dotp;

				p->name = savestr(hp->h_name);
				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 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];