ns_init.c

早期freebsd实现

			if (zp->z_source && (!strcmp(source, zp->z_source)) &&
			    (zp->z_state & Z_INCLUDE) == 0 && 
			    stat(zp->z_source, &f_time) == 0 &&
			    zp->z_ftime == f_time.st_mtime) {
				dprintf(1, (ddt, "cache is up to date\n"));
				if (source != cache_file)
					free(source);
				break; /* zone is already up to date */
			}

			/* file has changed, or hasn't been loaded yet */
			if (zp->z_source) {
				free(zp->z_source);
				remove_zone(fcachetab, 0);
			}
			zp->z_source = source;
			dprintf(1, (ddt, "reloading zone\n"));
			(void) db_load(zp->z_source, zp->z_origin, zp, 0);
			break;

		case Z_PRIMARY:
			source = savestr(buf);
#ifdef ALLOW_UPDATES
			if (getword(buf, sizeof(buf), fp)) {
				endline(fp);
				flag = buf;
				while (flag) {
				    cp = strchr(flag, ',');
				    if (cp)
					*cp++ = 0;
				    if (strcasecmp(flag, "dynamic") == 0)
					zp->z_state |= Z_DYNAMIC;
				    else if (strcasecmp(flag, "addonly") == 0)
					zp->z_state |= Z_DYNADDONLY;
				    else {
					syslog(LOG_ERR,
					       "%s: line %d: bad flag '%s'\n",
					       bootfile, lineno, flag);
				    }
				    flag = cp;
				}
			}
#else /*ALLOW_UPDATES*/
    		        endline(fp);
#endif

			dprintf(1, (ddt, ", source = %s\n", source));
			/*
			 * If we've loaded this file, and the file has
			 * not been modified and contains no $include,
			 * then there's no need to reload.
			 */
			if (zp->z_source && strcmp(source, zp->z_source) == 0 &&
			    (zp->z_state & Z_INCLUDE) == 0 && 
			    stat(zp->z_source, &f_time) == 0 &&
			    zp->z_ftime == f_time.st_mtime) {
				dprintf(1, (ddt, "zone is up to date\n"));
				free(source);
				break; /* zone is already up to date */
			}
			if (zp->z_source) {
				free(zp->z_source);
				remove_zone(hashtab, zp - zones);
			}
                        zp->z_source = source;
			zp->z_state &= ~Z_AUTH;
			dprintf(1, (ddt, "reloading zone\n"));
			if (db_load(zp->z_source, zp->z_origin, zp, 0) == 0)
				zp->z_state |= Z_AUTH;
#ifdef ALLOW_UPDATES
			/* Guarantee calls to ns_maint() */
			zp->z_refresh = maint_interval;
#else
			zp->z_refresh = 0;	/* no maintenance needed */
			zp->z_time = 0;
#endif
			break;

		case Z_SECONDARY:
#ifdef STUBS
		case Z_STUB:
#endif
			source = NULL;
			dprintf(1, (ddt, "\n\taddrs: "));
			do {
				if (!inet_aton(buf,
					       &zp->z_addr[zp->z_addrcnt])
				    ) {
					source = savestr(buf);
    		                        endline(fp);
					break;
				}
				dprintf(1, (ddt, "%s, ", buf));
				if (++zp->z_addrcnt > NSMAX - 1) {
					zp->z_addrcnt = NSMAX - 1;
					dprintf(1, (ddt,
						    "\nns.h NSMAX reached\n"));
				}
			} while (getword(buf, sizeof(buf), fp));
			dprintf(1, (ddt, "addrcnt = %d\n", zp->z_addrcnt));
			if (!source) {
				/*
				 * We will always transfer this zone again
				 * after a reload.
				 */
				sprintf(buf, "/%s/NsTmp%d.%d", _PATH_TMPDIR,
					getpid(), tmpnum++);
				source = savestr(buf);
				zp->z_state |= Z_TMP_FILE;
			} else
				zp->z_state &= ~Z_TMP_FILE;
			/*
			 * If we had a backup file name, and it was changed,
			 * free old zone and start over.  If we don't have
			 * current zone contents, try again now in case
			 * we have a new server on the list.
			 */
			if (zp->z_source && strcmp(source, zp->z_source)) {
				dprintf(1, (ddt, "backup file changed\n"));
				free(zp->z_source);
				zp->z_source = 0;
				zp->z_state &= ~Z_AUTH;
				zp->z_serial = 0;	/* force xfer */
                        	remove_zone(hashtab, zp - zones);
			}
			if (zp->z_source)
				free(source);
			else
				zp->z_source = source;
			if (!(zp->z_state & Z_AUTH))
				zoneinit(zp);
#ifdef FORCED_RELOAD
			else {
				/* 
				** Force secondary to try transfer right away 
				** after SIGHUP.
				*/
				if(reloading == 1)
					zp->z_time = tt.tv_sec;
			}
#endif /* FORCED_RELOAD */
			break;

		}
                zp->z_state |= Z_FOUND;
		dprintf(1, (ddt, "zone[%d] type %d: '%s'",
			    zp-zones, type,
			    *(zp->z_origin) == '\0' ? "." : zp->z_origin));
		if (zp->z_refresh && zp->z_time == 0)
			zp->z_time = zp->z_refresh + tt.tv_sec;
		if (zp->z_time <= tt.tv_sec)
			needmaint = 1;
		dprintf(1, (ddt, " z_time %d, z_refresh %d\n",
			    zp->z_time, zp->z_refresh));
	}
	(void) my_fclose(fp);
	lineno = slineno;
}

static void
zoneinit(zp)
	register struct zoneinfo *zp;
{
	struct stat sb;

	/*
	 * Try to load zone from backup file,
	 * if one was specified and it exists.
	 * If not, or if the data are out of date,
	 * we will refresh the zone from a primary
	 * immediately.
	 */
	if (zp->z_source == NULL)
		return;
	if (stat(zp->z_source, &sb) == -1 ||
	    db_load(zp->z_source, zp->z_origin, zp, 0) != 0) {
		/*
		 * Set zone to be refreshed immediately.
		 */
		zp->z_refresh = INIT_REFRESH;
		zp->z_retry = INIT_REFRESH;
		zp->z_time = tt.tv_sec;
		needmaint = 1;
	} else {
		zp->z_state |= Z_AUTH;
	}
}

#ifdef ALLOW_UPDATES
/*
 * Look for the authoritative zone with the longest matching RHS of dname
 * and return its zone # or zero if not found.
 */
int
findzone(dname, class)
	char *dname;
	int class;
{
	char *dZoneName, *zoneName;
	int dZoneNameLen, zoneNameLen;
	int maxMatchLen = 0;
	int maxMatchZoneNum = 0;
	int zoneNum;

	dprintf(4, (ddt, "findzone(dname=%s, class=%d)\n", dname, class));
#ifdef DEBUG
	if (debug >= 5) {
		fprintf(ddt, "zone dump:\n");
		for (zoneNum = 1; zoneNum < nzones; zoneNum++)
			printzoneinfo(zoneNum);
	}
#endif

	dZoneName = strchr(dname, '.');
	if (dZoneName == NULL)
		dZoneName = "";	/* root */
	else
		dZoneName++;	/* There is a '.' in dname, so use remainder of
				   string as the zone name */
	dZoneNameLen = strlen(dZoneName);
	for (zoneNum = 1; zoneNum < nzones; zoneNum++) {
		zoneName = (zones[zoneNum]).z_origin;
		zoneNameLen = strlen(zoneName);
		/* The zone name may or may not end with a '.' */
		if (zoneName[zoneNameLen - 1] == '.')
			zoneNameLen--;
		if (dZoneNameLen != zoneNameLen)
			continue;
		dprintf(5, (ddt, "about to strncasecmp('%s', '%s', %d)\n",
			    dZoneName, zoneName, dZoneNameLen));
		if (strncasecmp(dZoneName, zoneName, dZoneNameLen) == 0) {
			dprintf(5, (ddt, "match\n"));
			/*
			 * See if this is as long a match as any so far.
			 * Check if "<=" instead of just "<" so that if
			 * root domain (whose name length is 0) matches,
			 * we use it's zone number instead of just 0
			 */
			if (maxMatchLen <= zoneNameLen) {
				maxMatchZoneNum = zoneNum;
				maxMatchLen = zoneNameLen;
			}
		} else {
			dprintf(5, (ddt, "no match\n"));
		}
	}
	dprintf(4, (ddt, "findzone: returning %d\n", maxMatchZoneNum));
	return (maxMatchZoneNum);
}
#endif /* ALLOW_UPDATES */

static void
get_forwarders(fp)
	FILE *fp;
{
	char buf[BUFSIZ];
	register struct fwdinfo *fip = NULL, *ftp = NULL;

#ifdef SLAVE_FORWARD
	int forward_count = 0;
#endif

	dprintf(1, (ddt, "forwarders "));

	/* on mulitple forwarder lines, move to end of the list */
#ifdef SLAVE_FORWARD
	if (fwdtab != NULL){
		forward_count++;
		for (fip = fwdtab; fip->next != NULL; fip = fip->next)
			forward_count++;
	}
#else
	if (fwdtab != NULL) {
		for (fip = fwdtab; fip->next != NULL; fip = fip->next) {
			;
		}
	}
#endif /* SLAVE_FORWARD */

	while (getword(buf, sizeof(buf), fp)) {
		if (strlen(buf) == 0)
			break;
		dprintf(1, (ddt," %s",buf));
		if (ftp == NULL)
			ftp = (struct fwdinfo *)malloc(sizeof(struct fwdinfo));
		if (inet_aton(buf, &ftp->fwdaddr.sin_addr)) {
			ftp->fwdaddr.sin_port = ns_port;
			ftp->fwdaddr.sin_family = AF_INET;
		} else {
			syslog(LOG_ERR, "'%s' (ignored, NOT dotted quad)",
			       buf);
			dprintf(1, (ddt, " (ignored, NOT dotted quad)"));
			continue;	
		}
#ifdef FWD_LOOP
		if (aIsUs(ftp->fwdaddr.sin_addr)) {
			syslog(LOG_ERR,
			       "Forwarder '%s' ignored, my address",
			       buf);
			dprintf(1, (ddt, " (ignored, my address)"));
			continue;
		}
#endif /* FWD_LOOP */
		ftp->next = NULL;
		if (fwdtab == NULL)
			fwdtab = ftp;	/* First time only */
		else
			fip->next = ftp;
		fip = ftp;
		ftp = NULL;
#ifdef SLAVE_FORWARD
		forward_count++;
#endif /* SLAVE_FORWARD */
	}
	if (ftp)
		free((char *)ftp);
	
#ifdef SLAVE_FORWARD
	/*
	** Set the slave retry time to 60 seconds total divided
	** between each forwarder
	*/
	if (forward_count != 0) {
		slave_retry = (int) (60 / forward_count);
		if(slave_retry <= 0)
			slave_retry = 1;
	}
#endif

	dprintf(1, (ddt, "\n"));
#ifdef DEBUG
	if (debug > 2) {
		for (ftp = fwdtab; ftp != NULL; ftp = ftp->next) {
			fprintf(ddt,"ftp x%x [%s] next x%x\n",
				ftp,
				inet_ntoa(ftp->fwdaddr.sin_addr),
				ftp->next);
		}
	}
#endif
}

static void
free_forwarders()
{
	register struct fwdinfo *ftp, *fnext;

	for (ftp = fwdtab; ftp != NULL; ftp = fnext) {
		fnext = ftp->next;
		free((char *)ftp);
	}
	fwdtab = NULL;
}

static struct zoneinfo *
find_zone(name, type, class) 
	char *name;
	int type, class;
{
	register struct zoneinfo *zp;

        for (zp = &zones[1]; zp < &zones[nzones]; zp++) {
		if (zp->z_type == type && zp->z_class == class &&
		    strcasecmp(name, zp->z_origin) == 0) {
			dprintf(2, (ddt, ", old zone (%d)", zp - zones));
			return (zp);
		}
	}
	dprintf(2, (ddt, ", new zone"));
	return NULL;
}

#ifdef DEBUG
/* prints out the content of zones */
static void
content_zone(end) 
	int end;
{
	int i;

	for (i = 1;  i <= end;  i++) {
		printzoneinfo(i);
	}
}
#endif