ns_init.c

早期freebsd实现

#if !defined(lint) && !defined(SABER)
static char sccsid[] = "@(#)ns_init.c	4.38 (Berkeley) 3/21/91";
static char rcsid[] = "$Id:";
#endif /* not lint */

/*
 * ++Copyright++ 1986, 1990
 * -
 * Copyright (c) 1986, 1990
 *    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--
 */

#include <sys/param.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <netinet/in.h>
#include <arpa/nameser.h>
#include <arpa/inet.h>
#include <syslog.h>
#include <signal.h>
#include <resolv.h>
#include <stdio.h>
#include <errno.h>
#include <ctype.h>

#include "named.h"

#undef nsaddr

static void		zoneinit __P((struct zoneinfo *)),
			get_forwarders __P((FILE *)),
			boot_read __P((char *)),
#ifdef DEBUG
			content_zone __P((int)),
#endif
			free_forwarders __P((void));

static struct zoneinfo	*find_zone __P((char *, int, int));

/*
 * Read boot file for configuration info.
 */
void
ns_init(bootfile)
	char *bootfile;
{
	register struct zoneinfo *zp;
	static int loads = 0;			/* number of times loaded */

	dprintf(1, (ddt, "\nns_init(%s)\n", bootfile));
	gettime(&tt);

        if (loads == 0) {
		if ((zones =
			(struct zoneinfo *)calloc(64, sizeof(struct zoneinfo)))
					    == NULL) {
		    syslog(LOG_ERR,
			"Not enough memory to allocate initial zones array");
		    exit(1);
		}
		nzones = 1;		/* zone zero is cache data */
		/* allocate cache hash table, formerly the root hash table. */
		hashtab = savehash((struct hashbuf *)NULL);

		/* allocate root-hints/file-cache hash table */
		fcachetab = savehash((struct hashbuf *)NULL);
		/* init zone data */
		zones[0].z_type = Z_CACHE;
        } else {
		/* Mark previous zones as not yet found in boot file. */
		for (zp = &zones[1]; zp < &zones[nzones]; zp++)
			zp->z_state &= ~Z_FOUND;
#ifdef LOCALDOM
		if (localdomain) {
			free(localdomain);
			localdomain = NULL;
		}
#endif
		free_forwarders();
		free_netlist(enettab);
#ifdef XFRNETS
		free_netlist(&xfrnets);
#endif
#ifdef BOGUSNS
		free_netlist(&boglist);
#endif
		forward_only = 0;
	}

	dprintf(3, (ddt, "\n content of zones before loading \n"));
#ifdef DEBUG
        if (debug >= 3) {
        	content_zone(nzones - 1);
        }
#endif
	boot_read(bootfile);

        /* erase all old zones that were not found */
        for (zp = &zones[1]; zp < &zones[nzones]; zp++) {
            if (zp->z_type && (zp->z_state & Z_FOUND) == 0) {
		remove_zone(hashtab, zp - zones);
		bzero((char *) zp, sizeof(*zp));
		dprintf(2, (ddt, "\n zone #%d was removed\n", zp - zones));
	    }
        }
	dprintf(2, (ddt,"\n content of zones after loading\n"));

#ifdef DEBUG
	if (debug >= 2) {
        	content_zone(nzones-1);
        }
#endif

	/*
	 * Schedule calls to ns_maint().
	 */
	if (needmaint == 0)
		sched_maint();
	dprintf(1, (ddt, "exit ns_init()%s\n",
		    needmaint ? ", need maintenance immediately" : ""));
	loads++;
}

/*
 * Read the actual boot file.
 * Set up to recurse.
 */
static void
boot_read(bootfile)
	char *bootfile;
{
	register struct zoneinfo *zp;
	char buf[BUFSIZ], obuf[BUFSIZ], *source;
	FILE *fp;
	int type;
	int class;
#ifdef GEN_AXFR
	char *class_p;
#endif
	struct stat f_time;
	static int tmpnum = 0;		/* unique number for tmp zone files */
#ifdef ALLOW_UPDATES
	char *cp, *flag;
#endif
	int slineno;			/* Saved global line number. */

	if ((fp = fopen(bootfile, "r")) == NULL) {
		syslog(LOG_ERR, "%s: %m", bootfile);
		exit(1);
	}

	slineno = lineno;
	lineno = 0;

	while (!feof(fp) && !ferror(fp)) {
		if (!getword(buf, sizeof(buf), fp))
			continue;
		/* read named.boot keyword and process args */
		if (strcasecmp(buf, "directory") == 0) {
			(void) getword(buf, sizeof(buf), fp);
			if (chdir(buf) < 0) {
				syslog(LOG_CRIT, "directory %s: %m\n",
					buf);
				exit(1);
			}
			continue;
		} else if (strcasecmp(buf, "sortlist") == 0) {
			get_netlist(fp, enettab, ALLOW_NETS, buf);
			continue;
		} else if (strcasecmp(buf, "forwarders") == 0) {
			get_forwarders(fp);
			continue;
		} else if (strcasecmp(buf, "slave") == 0) {
			forward_only++;
			endline(fp);
			continue;
#ifdef BOGUSNS
		} else if (strcasecmp(buf, "bogusns") == 0) {
			get_netlist(fp, &boglist, ALLOW_HOSTS, buf);
			continue;
#endif
#ifdef XFRNETS
		} else if ((strcasecmp(buf, "tcplist") == 0) ||
			   (strcasecmp(buf, "xfrnets") == 0)) {
			get_netlist(fp, &xfrnets, ALLOW_NETS, buf);
			continue;
#endif
#ifdef LOCALDOM
		} else if (strcasecmp(buf, "domain") == 0) {
			if (getword(buf, sizeof(buf), fp))
				localdomain = savestr(buf);
			endline(fp);
			continue;
#endif
		} else if (strcasecmp(buf, "include") == 0) {
			if (getword(buf, sizeof(buf), fp))
				boot_read(buf);
			endline(fp);
			continue;
		} else if (strcasecmp(buf, "cache") == 0) {
			type = Z_CACHE;
			class = C_IN;
#ifdef GEN_AXFR
			if (class_p = strchr(buf, '/'))
				class = get_class(class_p+1);
#endif
		} else if (strncasecmp(buf, "primary", 7) == 0) {
			type = Z_PRIMARY;
			class = C_IN;
#ifdef GEN_AXFR
			if (class_p = strchr(buf, '/'))
				class = get_class(class_p+1);
#endif
		} else if (strncasecmp(buf, "secondary", 9) == 0) {
			type = Z_SECONDARY;
			class = C_IN;
#ifdef GEN_AXFR
			if (class_p = strchr(buf, '/'))
				class = get_class(class_p+1);
#endif
#ifdef STUBS
		} else if (strncasecmp(buf, "stub", 4) == 0) {
			type = Z_STUB;
			class = C_IN;
#ifdef GEN_AXFR
			if (class_p = strchr(buf, '/'))
				class = get_class(class_p+1);
#endif
#endif
		} else {
			syslog(LOG_ERR, "%s: line %d: unknown field '%s'\n",
				bootfile, lineno+1, buf);
			endline(fp);
			continue;
		}

		/*
		 * read zone origin
		 */
		if (!getword(obuf, sizeof(obuf), fp)) {
			syslog(LOG_ERR, "%s: line %d: missing origin\n",
			    bootfile, lineno);
			continue;
		}
		dprintf(1, (ddt, "zone origin %s", obuf));
		if (obuf[0] == '.' && obuf[1] == '\0')
			obuf[0] = '\0';
		/*
		 * read source file or host address
		 */
		if (!getword(buf, sizeof(buf), fp)) {
			syslog(LOG_ERR, "%s: line %d: missing %s\n",
				bootfile, lineno, 
#ifdef STUBS
			   (type == Z_SECONDARY || type == Z_STUB)
#else
			   (type == Z_SECONDARY)
#endif
			       ?"host address"
			       :"source file");
			continue;
		}

		/* check for previous instance of this zone (reload) */
		if (!(zp = find_zone(obuf, type, class))) {
			if (type == Z_CACHE) {
				zp = &zones[0];
				zp->z_origin = "";
				goto gotzone;
			}
			for (zp = &zones[1]; zp < &zones[nzones]; zp++)
				if (zp->z_type == Z_NIL)
					goto gotzone;
			/*
			 * this code assumes that nzones never decreases
			 */
			if (nzones % 64 == 0) {
			    dprintf(1, (ddt,
					"Reallocating zones structure\n"));
			    /*
			     * Realloc() not used since it might damage zones
			     * if an error occurs
			     */
			    zp = (struct zoneinfo *)
				malloc((64 + nzones)
				       * sizeof(struct zoneinfo));
			    if (zp == (struct zoneinfo *)0) {
				    syslog(LOG_ERR,
					   "no memory for more zones");
				    dprintf(1, (ddt,
						"Out of memory for new zones\n"
						)
					    );
				    endline(fp);
				    continue;
			    }
			    bcopy((char *)zones, (char *)zp,
				  nzones * sizeof(struct zoneinfo));
			    bzero((char *)&zp[nzones],
				  64 * sizeof(struct zoneinfo));
			    free(zones);
			    zones = zp;
			}
			zp = &zones[nzones++];
	gotzone:
			zp->z_origin = savestr(obuf);
			zp->z_type = type;
			zp->z_class = class;
		}
		zp->z_addrcnt = 0;

		switch (type) {
		case Z_CACHE:
			source = savestr(buf);
			dprintf(1, (ddt, ", source = %s\n", source));
			zp->z_refresh = 0;	/* by default, no dumping */
			if (getword(buf, sizeof(buf), fp)) {
#ifdef notyet
				zp->z_refresh = atoi(buf);
				if (zp->z_refresh <= 0) {
					syslog(LOG_ERR,
				"%s: line %d: bad refresh time '%s', ignored\n",
						bootfile, lineno, buf);
					zp->z_refresh = 0;
				} else if (cache_file == NULL)
					cache_file = source;
#else
				syslog(LOG_WARNING,
				"%s: line %d: cache refresh ignored\n",
					bootfile, lineno);
#endif
				endline(fp);
			}
			/*
			 * If we've loaded this file, and the file has
			 * not been modified and contains no $include,
			 * then there's no need to reload.
			 */