4.4BSD/usr/src/contrib/bind-4.9/named/ns_maint.c
#if !defined(lint) && !defined(SABER)
static char sccsid[] = "@(#)ns_maint.c 4.39 (Berkeley) 3/2/91";
static char rcsid[] = "$Id: ns_maint.c,v 4.9.1.2 1993/05/17 10:00:01 vixie Exp $";
#endif /* not lint */
/*
* ++Copyright++ 1986, 1988
* -
* Copyright (c) 1986, 1988 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/types.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <arpa/nameser.h>
#include <sys/wait.h>
#include <stdio.h>
#include <syslog.h>
#include <signal.h>
#include <errno.h>
#include "../conf/portability.h"
#include "../conf/options.h"
#include "ns.h"
#include "db.h"
#include "pathnames.h"
#ifdef USE_UTIME
# include <utime.h>
#endif
extern void gettime();
extern int maint_interval;
extern int needzoneload;
extern u_short ns_port;
void ns_maint(), sched_maint(), remove_zone(),
startxfer(), abortxfer(), loadxfer();
#ifdef DEBUG
void printzoneinfo();
#endif
int xfers_running; /* number of xfers running */
int xfers_deferred; /* number of needed xfers not run yet */
static int alarm_pending;
/*
* Invoked at regular intervals by signal interrupt; refresh all secondary
* zones from primary name server and remove old cache entries. Also,
* ifdef'd ALLOW_UPDATES, dump database if it has changed since last
* dump/bootup.
*/
void
ns_maint()
{
register struct zoneinfo *zp;
int zonenum;
gettime(&tt);
#ifdef DEBUG
if (debug)
fprintf(ddt,"\nns_maint(); now %s", ctime(&tt.tv_sec));
#endif
xfers_deferred = 0;
alarm_pending = 0;
for (zp = zones, zonenum = 0; zp < &zones[nzones]; zp++, zonenum++) {
#ifdef DEBUG
if (debug >= 2)
printzoneinfo(zonenum);
#endif
if (tt.tv_sec >= zp->z_time && zp->z_refresh > 0) {
/*
* Set default time for next action first,
* so that it can be changed later if necessary.
*/
zp->z_time = tt.tv_sec + zp->z_refresh;
switch (zp->z_type) {
case Z_CACHE:
doachkpt();
break;
case Z_SECONDARY:
if ((zp->z_state & Z_NEED_RELOAD) == 0) {
if (zp->z_state & Z_XFER_RUNNING)
abortxfer(zp);
else if (xfers_running < MAX_XFERS_RUNNING)
startxfer(zp);
else {
zp->z_state |= Z_NEED_XFER;
++xfers_deferred;
#ifdef DEBUG
if (debug > 1)
fprintf(ddt,
"xfer deferred for %s\n",
zp->z_origin);
#endif
}
}
break;
#ifdef ALLOW_UPDATES
case Z_PRIMARY:
/*
* Checkpoint the zone if it has changed
* since we last checkpointed
*/
if (zp->z_state & Z_CHANGED)
zonedump(zp);
break;
#endif /* ALLOW_UPDATES */
}
gettime(&tt);
}
}
sched_maint();
#ifdef DEBUG
if (debug)
fprintf(ddt, "exit ns_maint()\n");
#endif
}
/*
* Find when the next refresh needs to be and set
* interrupt time accordingly.
*/
void
sched_maint()
{
register struct zoneinfo *zp;
struct itimerval ival;
time_t next_refresh = 0;
static time_t next_alarm;
for (zp = zones; zp < &zones[nzones]; zp++)
if (zp->z_time != 0 &&
(next_refresh == 0 || next_refresh > zp->z_time))
next_refresh = zp->z_time;
/*
* Schedule the next call to ns_maint.
* Don't visit any sooner than maint_interval.
*/
bzero((char *)&ival, sizeof (ival));
if (next_refresh != 0) {
if (next_refresh == next_alarm && alarm_pending) {
#ifdef DEBUG
if (debug)
fprintf(ddt,"sched_maint: no schedule change\n");
#endif
return;
}
/*
* tv_sec can be an unsigned long, so we can't let
* it go negative.
*/
if (next_refresh < tt.tv_sec)
next_refresh = tt.tv_sec;
ival.it_value.tv_sec = next_refresh - tt.tv_sec;
if ((long) ival.it_value.tv_sec < maint_interval)
ival.it_value.tv_sec = maint_interval;
next_alarm = next_refresh;
alarm_pending = 1;
}
(void) setitimer(ITIMER_REAL, &ival, (struct itimerval *)NULL);
#ifdef DEBUG
if (debug)
fprintf(ddt,"sched_maint: Next interrupt in %d sec\n",
ival.it_value.tv_sec);
#endif
}
/*
* Start an asynchronous zone transfer for a zone.
* Depends on current time being in tt.
* The caller must call sched_maint after startxfer.
*/
void
startxfer(zp)
struct zoneinfo *zp;
{
static char *argv[NSMAX + 20], argv_ns[NSMAX][MAXDNAME];
int cnt, argc = 0, argc_ns = 0, pid, omask;
char debug_str[10];
char serial_str[10];
char port_str[10];
#ifdef DEBUG
if (debug)
fprintf(ddt,"startxfer() %s\n", zp->z_origin);
#endif
argv[argc++] = "named-xfer";
argv[argc++] = "-z";
argv[argc++] = zp->z_origin;
argv[argc++] = "-f";
argv[argc++] = zp->z_source;
argv[argc++] = "-s";
sprintf(serial_str, "%lu", zp->z_serial);
argv[argc++] = serial_str;
if (zp->z_state & Z_SYSLOGGED)
argv[argc++] = "-q";
argv[argc++] = "-P";
sprintf(port_str, "%d", ns_port);
argv[argc++] = port_str;
#ifdef DEBUG
if (debug) {
argv[argc++] = "-d";
sprintf(debug_str, "%d", debug);
argv[argc++] = debug_str;
argv[argc++] = "-l";
argv[argc++] = _PATH_XFERDDT;
if (debug > 5) {
argv[argc++] = "-t";
argv[argc++] = _PATH_XFERTRACE;
}
}
#endif
/*
* Copy the server ip addresses into argv, after converting
* to ascii and saving the static inet_ntoa result
*/
for (cnt = 0; cnt < zp->z_addrcnt; cnt++) {
struct in_addr a;
a = zp->z_addr[cnt];
if (aIsUs(a) && !haveComplained(zp->z_origin, (char*)startxfer)) {
syslog(LOG_ERR, "attempted to fetch zone %s from self (%s)",
zp->z_origin, inet_ntoa(a));
continue;
}
argv[argc++] = strcpy(argv_ns[argc_ns++], inet_ntoa(a));
}
argv[argc] = 0;
#ifdef DEBUG
#ifdef ECHOARGS
if (debug) {
int i;
for (i = 0; i < argc; i++)
fprintf(ddt, "Arg %d=%s\n", i, argv[i]);
}
#endif /* ECHOARGS */
#endif /* DEBUG */
#ifdef SYSV
#define vfork fork
#else
gettime(&tt);
omask = sigblock(sigmask(SIGCHLD));
#endif
if ((pid = vfork()) == -1) {
#ifdef DEBUG
if (debug)
fprintf(ddt, "xfer [v]fork: %d\n", errno);
#endif
syslog(LOG_ERR, "xfer [v]fork: %m");
#ifndef SYSV
(void) sigsetmask(omask);
#endif
zp->z_time = tt.tv_sec + 10;
return;
}
if (pid == 0) {
/* child */
execv(_PATH_XFER, argv);
syslog(LOG_ERR, "can't exec %s: %m", _PATH_XFER);
_exit(XFER_FAIL); /* avoid duplicate buffer flushes */
}
/* parent */
#ifdef DEBUG
if (debug)
fprintf(ddt, "started xfer child %d\n", pid);
#endif
zp->z_state &= ~Z_NEED_XFER;
zp->z_state |= Z_XFER_RUNNING;
zp->z_xferpid = pid;
xfers_running++;
zp->z_time = tt.tv_sec + MAX_XFER_TIME;
#ifndef SYSV
(void) sigsetmask(omask);
#endif
}
#ifdef DEBUG
void
printzoneinfo(zonenum)
int zonenum;
{
struct timeval tt;
struct zoneinfo *zp = &zones[zonenum];
char *ZoneType;
if (!debug)
return; /* Else fprintf to ddt will bomb */
fprintf(ddt, "printzoneinfo(%d):\n", zonenum);
gettime(&tt);
switch (zp->z_type) {
case Z_PRIMARY: ZoneType = "Primary"; break;
case Z_SECONDARY: ZoneType = "Secondary"; break;
case Z_CACHE: ZoneType = "Cache"; break;
default: ZoneType = "Unknown";
}
if (zp->z_origin != NULL && (zp->z_origin[0] == '\0'))
fprintf(ddt,"origin ='.'");
else
fprintf(ddt,"origin ='%s'", zp->z_origin);
fprintf(ddt,", type = %s", ZoneType);
if (zp->z_source)
fprintf(ddt,", source = %s\n", zp->z_source);
fprintf(ddt,"z_refresh = %ld", zp->z_refresh);
fprintf(ddt,", retry = %ld", zp->z_retry);
fprintf(ddt,", expire = %ld", zp->z_expire);
fprintf(ddt,", minimum = %ld", zp->z_minimum);
fprintf(ddt,", serial = %lu\n", zp->z_serial);
fprintf(ddt,"z_time = %d", zp->z_time);
if (zp->z_time) {
fprintf(ddt,", now time : %d sec", tt.tv_sec);
fprintf(ddt,", time left: %d sec", zp->z_time - tt.tv_sec);
}
fprintf(ddt,"; state %x\n", zp->z_state);
}
#endif /* DEBUG */
/*
* remove_zone (htp, zone) --
* Delete all RR's in the zone "zone" under specified hash table.
*/
void
remove_zone(htp, zone)
register struct hashbuf *htp;
register int zone;
{
register struct databuf *dp, *pdp;
register struct namebuf *np, *pnp, *npn;
struct namebuf **npp, **nppend;
nppend = htp->h_tab + htp->h_size;
for (npp = htp->h_tab; npp < nppend; npp++)
for (pnp = NULL, np = *npp; np != NULL; np = npn) {
for (pdp = NULL, dp = np->n_data; dp != NULL; ) {
if (dp->d_zone == zone)
dp = rm_datum(dp, np, pdp);
else {
pdp = dp;
dp = dp->d_next;
}
}
if (np->n_hash) {
/* call recursively to remove subdomains. */
remove_zone(np->n_hash, zone);
/* if now empty, free it */
if (np->n_hash->h_cnt == 0) {
free((char*)np->n_hash);
np->n_hash = NULL;
}
}
if ((np->n_hash == NULL) && (np->n_data == NULL)) {
npn = rm_name(np, npp, pnp);
htp->h_cnt--;
} else {
npn = np->n_next;
pnp = np;
}
}
}
/*
* Abort an xfer that has taken too long.
*/
void
abortxfer(zp)
register struct zoneinfo *zp;
{
kill(zp->z_xferpid, SIGKILL); /* don't trust it at all */
#ifdef DEBUG
if (debug)
fprintf(ddt, "Killed child %d (zone %s) due to timeout\n",
zp->z_xferpid, zp->z_origin);
#endif /* DEBUG */
zp->z_time = tt.tv_sec + zp->z_retry;
}
/*
* SIGCHLD signal handler: process exit of xfer's.
* (Note: also called when outgoing transfer completes.)
*/
SIG_FN
endxfer()
{
register struct zoneinfo *zp;
int pid, xfers = 0;
WAIT_T status;
gettime(&tt);
#if defined(USE_WAIT3)
while ((pid =
wait3(&status, WNOHANG, (struct rusage *)NULL)) > 0) {
#else /* USE_WAIT3 */
{
int stat;
pid = wait(&stat);
status.w_termsig = stat & 0x7f;
status.w_retcode = stat >> 8;
#endif /* USE_WAIT3 */
int exitstatus = WIFEXITED(status) ?WEXITSTATUS(status) :0;
for (zp = zones; zp < &zones[nzones]; zp++)
if (zp->z_xferpid == pid) {
xfers++;
xfers_running--;
zp->z_xferpid = 0;
zp->z_state &= ~Z_XFER_RUNNING;
#ifdef DEBUG
if (debug)
fprintf(ddt,
"\nendxfer: child %d zone %s returned status=%d termsig=%d\n",
pid, zp->z_origin, exitstatus,
WIFSIGNALED(status) ?WTERMSIG(status) :-1);
#endif
if (WIFSIGNALED(status)) {
if (WTERMSIG(status) != SIGKILL) {
syslog(LOG_ERR,
"named-xfer exited with signal %d\n",
WTERMSIG(status));
#ifdef DEBUG
if (debug)
fprintf(ddt,
"\tchild termination with signal %d\n",
WTERMSIG(status));
#endif
}
zp->z_time = tt.tv_sec + zp->z_retry;
} else switch (exitstatus) {
case XFER_UPTODATE:
zp->z_state &= ~Z_SYSLOGGED;
zp->z_lastupdate = tt.tv_sec;
zp->z_time = tt.tv_sec + zp->z_refresh;
/*
* Restore Z_AUTH in case expired,
* but only if there were no errors
* in the zone file.
*/
if ((zp->z_state & Z_DB_BAD) == 0)
zp->z_state |= Z_AUTH;
if (zp->z_source) {
#if defined(USE_UTIME)
struct utimbuf t;
t.actime = tt.tv_sec;
t.modtime = tt.tv_sec;
(void) utime(zp->z_source, &t);
#else
struct timeval t[2];
t[0] = tt;
t[1] = tt;
(void) utimes(zp->z_source, t);
#endif /* USE_UTIME */
}
break;
case XFER_SUCCESS:
zp->z_state |= Z_NEED_RELOAD;
zp->z_state &= ~Z_SYSLOGGED;
needzoneload++;
break;
case XFER_TIMEOUT:
#ifdef DEBUG
if (debug) fprintf(ddt,
"zoneref: Masters for secondary zone %s unreachable\n",
zp->z_origin);
#endif
if ((zp->z_state & Z_SYSLOGGED) == 0) {
zp->z_state |= Z_SYSLOGGED;
syslog(LOG_WARNING,
"zoneref: Masters for secondary zone %s unreachable",
zp->z_origin);
}
zp->z_time = tt.tv_sec + zp->z_retry;
break;
default:
if ((zp->z_state & Z_SYSLOGGED) == 0) {
zp->z_state |= Z_SYSLOGGED;
syslog(LOG_ERR,
"named-xfer exit code %d",
exitstatus);
}
/* FALLTHROUGH */
case XFER_FAIL:
zp->z_state |= Z_SYSLOGGED;
zp->z_time = tt.tv_sec + zp->z_retry;
break;
}
break;
}
}
if (xfers) {
for (zp = zones;
xfers_deferred != 0 && xfers_running < MAX_XFERS_RUNNING &&
zp < &zones[nzones]; zp++)
if (zp->z_state & Z_NEED_XFER) {
xfers_deferred--;
startxfer(zp);
}
sched_maint();
}
#if defined(SYSV)
(void)signal(SIGCLD, endxfer);
#endif
}
/*
* Reload zones whose transfers have completed.
*/
void
loadxfer()
{
register struct zoneinfo *zp;
gettime(&tt);
for (zp = zones; zp < &zones[nzones]; zp++)
if (zp->z_state & Z_NEED_RELOAD) {
#ifdef DEBUG
if (debug)
fprintf(ddt, "loadxfer() '%s'\n",
zp->z_origin[0] ? zp->z_origin : ".");
#endif
zp->z_state &= ~(Z_NEED_RELOAD|Z_AUTH);
remove_zone(hashtab, zp - zones);
if (db_load(zp->z_source, zp->z_origin, zp, 0) == 0)
zp->z_state |= Z_AUTH;
if (zp->z_state & Z_TMP_FILE)
(void) unlink(zp->z_source);
}
sched_maint();
}