host.c

早期freebsd实现

/*
 * ++Copyright++ 1986
 * -
 * Copyright (c) 1986
 *    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 the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 * 	This product includes software developed by the University of
 * 	California, Berkeley and its contributors.
 * 4. 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 BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * -
 * Portions Copyright (c) 1993 by Digital Equipment Corporation.
 * 
 * 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, and that
 * the name of Digital Equipment Corporation not be used in advertising or
 * publicity pertaining to distribution of the document or software without
 * specific, written prior permission.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
 * CORPORATION 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.
 * -
 * --Copyright--
 */

#ifndef lint
char copyright[] =
"@(#) Copyright (c) 1986 Regents of the University of California.\n\
 portions Copyright (c) 1993 Digital Equipment Corporation\n\
 All rights reserved.\n";
#endif /* not lint */

/*
 * Actually, this program is from Rutgers University, however it is 
 * based on nslookup and other pieces of named tools, so it needs
 * that copyright notice.
 */

#ifndef lint
static char rcsid[] = "$Id: host.c,v 4.9.1.6 1993/12/06 00:43:14 vixie Exp $";
#endif /* not lint */

#include <sys/types.h>
#include <sys/param.h>
#include <sys/socket.h>

#include <netinet/in.h>
#include <arpa/inet.h>
#include <arpa/nameser.h>

#include <stdio.h>
#include <netdb.h>
#include <resolv.h>
#include <ctype.h>

#include "../conf/portability.h"

extern int h_errno;

#define NUMMX 50

#define  SUCCESS		0
#define  TIME_OUT		-1
#define  NO_INFO 		-2
#define  ERROR 			-3
#define  NONAUTH 		-4

#define NAME_LEN 256

#ifndef T_TXT
#define T_TXT 16
#endif
#ifndef NO_DATA
#define NO_DATA NO_ADDRESS
#endif
#ifndef C_HS
#define C_HS 4
#endif

int sockFD;
FILE *filePtr;
char *DecodeError();

static struct __res_state orig;
extern struct __res_state _res;
static u_char *cname = NULL;
int getclass = C_IN;
int gettype;
int verbose = 0;
int list = 0;
int server_specified = 0;

char *pr_class(), *pr_rr(), *pr_cdname(), *pr_type();
extern char *hostalias();

main(c, v)
	char **v;
{
	unsigned addr;
	register struct hostent *hp;
	register char *s;
	register inverse = 0;
	register waitmode = 0;
	u_char *oldcname;
	int ncnames;

	res_init();
	_res.retrans = 5;

	if (c < 2) {
		fprintf(stderr, "Usage: host [-w] [-v] [-r] [-d] [-t querytype] [-c class] [-a] host [server]\n  -w to wait forever until reply\n  -v for verbose output\n  -r to disable recursive processing\n  -d to turn on debugging output\n  -t querytype to look for a specific type of information\n  -c class to look for non-Internet data\n  -a is equivalent to '-v -t *'\n");
		exit(1);
	}
	while (c > 2 && v[1][0] == '-') {
		if (strcmp (v[1], "-w") == 0) {
			_res.retry = 1;
			_res.retrans = 15;
			waitmode = 1;
			v++;
			c--;
		}
		else if (strcmp (v[1], "-r") == 0) {
			_res.options &= ~RES_RECURSE;
			v++;
			c--;
		}
		else if (strcmp (v[1], "-d") == 0) {
			_res.options |= RES_DEBUG;
			v++;
			c--;
		}
		else if (strcmp (v[1], "-v") == 0) {
			verbose = 1;
			v++;
			c--;
		}
		else if (strcmp (v[1], "-l") == 0) {
			list = 1;
			v++;
			c--;
		}
		else if (strncmp (v[1], "-t", 2) == 0) {
			v++;
			c--;
			gettype = parsetype(v[1]);
			v++;
			c--;
		}
		else if (strncmp (v[1], "-c", 2) == 0) {
			v++;
			c--;
			getclass = parseclass(v[1]);
			v++;
			c--;
		}
		else if (strcmp (v[1], "-a") == 0) {
			verbose = 1;
			gettype = T_ANY;
			v++;
			c--;
		}		
        }
	if (c > 2) {
		s = v[2];
		server_specified++;
		
		addr = inet_addr(s);
		if (addr == -1) {
		  hp = gethostbyname(s);
		  if (hp == NULL) {
		    fprintf(stderr,"Error in looking up server name:\n");
		    hperror(h_errno);
		    exit(1);
		  }
		  _res.nsaddr.sin_addr = *(struct in_addr *)hp->h_addr;
		  printf("Using domain server:\n");
		  printanswer(hp);
		}
		else {
		  _res.nsaddr.sin_family = AF_INET;
		  _res.nsaddr.sin_addr.s_addr = addr;
		  _res.nsaddr.sin_port = htons(NAMESERVER_PORT);
		  printf("Using domain server %s:\n",
			 inet_ntoa(_res.nsaddr.sin_addr));
		}
		_res.nscount = 1;
		_res.retry = 2;
	      }
	if (strcmp (v[1], ".") == 0)
	  addr = -1;
	else
	  addr = inet_addr(v[1]);
	hp = NULL;
	h_errno = TRY_AGAIN;
/*
 * we handle default domains ourselves, thank you
 */
	_res.options &= ~RES_DEFNAMES;

        if (list)
	  exit(ListHosts(v[1], gettype ? gettype : T_A));
	oldcname = NULL;
	ncnames = 5;
	while (hp == NULL && h_errno == TRY_AGAIN) {
	  if (addr == -1) {
	      cname = NULL;
	      if (oldcname == NULL)
		hp = (struct hostent *)gethostinfo(v[1]);
	      else
		hp = (struct hostent *)gethostinfo(oldcname);
	      if (cname) {
		if (ncnames-- == 0) {
		  printf("Too many cnames.  Possible loop.\n");
		  exit(1);
		}
		oldcname = cname;
		hp = NULL;
		h_errno = TRY_AGAIN;
		continue;
	      }
	  }
	  else {
	    hp = gethostbyaddr((char*)&addr, 4, AF_INET);
	    if (hp)
	      printanswer(hp);
	  }
	  if (!waitmode)
	    break;
	}

	if (hp == NULL) {
	  hperror(h_errno);
	  exit(1);
	}

	exit(0);

}

parsetype(s)
	char *s;
{
if (strcmp(s,"a") == 0)
  return(1);
if (strcmp(s,"ns") == 0)
  return(2);
if (strcmp(s,"md") == 0)
  return(3);
if (strcmp(s,"mf") == 0)
  return(4);
if (strcmp(s,"cname") == 0)
  return(5);
if (strcmp(s,"soa") == 0)
  return(6);
if (strcmp(s,"mb") == 0)
  return(7);
if (strcmp(s,"mg") == 0)
  return(8);
if (strcmp(s,"mr") == 0)
  return(9);
if (strcmp(s,"null") == 0)
  return(10);
if (strcmp(s,"wks") == 0)
  return(11);
if (strcmp(s,"ptr") == 0)
  return(12);
if (strcmp(s,"hinfo") == 0)
  return(13);
if (strcmp(s,"minfo") == 0)
  return(14);
if (strcmp(s,"mx") == 0)
  return(15);
if (strcmp(s,"txt") == 0)	/* Roy */
  return(T_TXT);		/* Roy */
if (strcmp(s,"afsdb") == 0)
  return(T_AFSDB);
if (strcmp(s,"uinfo") == 0)
  return(100);
if (strcmp(s,"uid") == 0)
  return(101);
if (strcmp(s,"gid") == 0)
  return(102);
if (strcmp(s,"unspec") == 0)
  return(103);
if (strcmp(s,"any") == 0)
  return(255);
if (strcmp(s,"*") == 0)
  return(255);
if (atoi(s))
  return(atoi(s));
fprintf(stderr, "Invalid query type: %s\n", s);
exit(2);
}

parseclass(s)
	char *s;
{
if (strcmp(s,"in") == 0)
  return(C_IN);
if (strcmp(s,"hs") == 0)
  return(C_HS);
if (strcmp(s,"any") == 0)
  return(C_ANY);
if (atoi(s))
  return(atoi(s));
fprintf(stderr, "Invalid query class: %s\n", s);
exit(2);
}

printanswer(hp)
	register struct hostent *hp;
{
	register char **cp;
	register long **hptr;

	printf("Name: %s\n", hp->h_name);
	printf("Address:");
	for (hptr = (long **)hp->h_addr_list; *hptr; hptr++)
	  printf(" %s", inet_ntoa(*(struct in_addr *)*hptr));
	printf("\nAliases:");
	for (cp = hp->h_aliases; cp && *cp && **cp; cp++)
		printf(" %s", *cp);
	printf("\n\n");
}

hperror(errno) 
int errno;
{
switch(errno) {
	case HOST_NOT_FOUND:
		fprintf(stderr,"Host not found.\n");
		break;
	case TRY_AGAIN:
		fprintf(stderr,"Host not found, try again.\n");
		break;
	case NO_RECOVERY:
		fprintf(stderr,"No recovery, Host not found.\n");
		break;
	case NO_ADDRESS:
		fprintf(stderr,"There is an entry for this host, but it doesn't have ");
		switch (gettype) {
			case T_A:
				fprintf(stderr,"an Internet address.\n");
				break;
			case T_NS:
				fprintf(stderr,"a Name Server.\n");
				break;
			case T_MD:
				fprintf(stderr,"a Mail Destination.\n");
				break;
			case T_MF:
				fprintf(stderr,"a Mail Forwarder.\n");
				break;
			case T_CNAME:
				fprintf(stderr,"a Canonical Name.\n");
				break;
			case T_SOA:
				fprintf(stderr,"a Start of Authority record.\n");
				break;
			case T_MB:
				fprintf(stderr,"a Mailbox Domain Name.\n");
				break;
			case T_MG:
				fprintf(stderr,"a Mail Group Member.\n");
				break;
			case T_MR:
				fprintf(stderr,"a Mail Rename Name.\n");
				break;
			case T_NULL:
				fprintf(stderr,"a Null Resource record.\n");
				break;
			case T_WKS:
				fprintf(stderr,"any Well Known Service information.\n");
				break;
			case T_PTR:
				fprintf(stderr,"a Pointer record.\n");
				break;
			case T_HINFO:
				fprintf(stderr,"any Host Information.\n");
				break;
			case T_MINFO:
				fprintf(stderr,"any Mailbox Information.\n");
				break;
			case T_MX:
				fprintf(stderr,"a Mail Exchanger record.\n");
				break;
			case T_TXT:
				fprintf(stderr,"a Text record.\n");
				break;
			case T_UINFO:
				fprintf(stderr,"any User Information.\n");
				break;
			case T_UID:
				fprintf(stderr,"a User ID.\n");
				break;
			case T_GID:
				fprintf(stderr,"a Group ID.\n");
				break;
			case T_UNSPEC:
				fprintf(stderr,"any Unspecified Format data.\n");
				break;
			default:
				fprintf(stderr,"the information you requested.\n");
				break;
			}
		break;
	}
}


typedef union {
	HEADER qb1;
	u_char qb2[PACKETSZ];
} querybuf;

static u_char hostbuf[BUFSIZ+1];

gethostinfo(name)
	char *name;
{
	register char *cp, **domain;
	int n;
	int hp;
	int nDomain;

	if (strcmp(name, ".") == 0)
		return(getdomaininfo(name, NULL));
	for (cp = name, n = 0; *cp; cp++)
		if (*cp == '.')
			n++;
	if (n && cp[-1] == '.') {
		if (cp[-1] == '.')
			cp[-1] = 0;
		hp = getdomaininfo(name, (char *)NULL);
		if (cp[-1] == 0)
			cp[-1] = '.';
		return (hp);
	}
	if (n == 0 && (cp = hostalias(name))) {
	        if (verbose)