2.11BSD/src/usr.sbin/named/named/ns_maint.c
/*
* Copyright (c) 1986 Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms are permitted
* provided that this notice is preserved and that due credit is given
* to the University of California at Berkeley. The name of the University
* may not be used to endorse or promote products derived from this
* software without specific prior written permission. This software
* is provided ``as is'' without express or implied warranty.
*/
#ifndef lint
static char sccsid[] = "@(#)ns_maint.c 4.23 (Berkeley) 2/28/88";
#endif /* not lint */
#include <sys/param.h>
#include <sys/socket.h>
#include <sys/time.h>
#if defined(SYSV)
#include <unistd.h>
#endif SYSV
#include <netinet/in.h>
#include <stdio.h>
#include <syslog.h>
#include <signal.h>
#include <errno.h>
#include <arpa/nameser.h>
#include "ns.h"
#include "db.h"
extern int errno;
extern u_long maint_interval;
/*
* 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.
*/
ns_maint()
{
register struct zoneinfo *zp;
struct itimerval ival;
time_t next_refresh = 0;
int zonenum;
#ifdef DEBUG
if (debug)
fprintf(ddt,"ns_maint()\n");
#endif
for (zp = zones, zonenum = 0; zp < &zones[nzones]; zp++, zonenum++) {
switch(zp->z_type) {
#ifdef ALLOW_UPDATES
case Z_PRIMARY:
#endif ALLOW_UPDATES
case Z_SECONDARY:
case Z_CACHE:
break;
default:
continue;
}
gettime(&tt);
#ifdef DEBUG
if (debug >= 2)
printzoneinfo(zonenum);
#endif
if (tt.tv_sec >= zp->z_time && zp->z_refresh > 0) {
if (zp->z_type == Z_CACHE)
doachkpt();
if (zp->z_type == Z_SECONDARY)
zoneref(zp);
#ifdef ALLOW_UPDATES
/*
* Checkpoint the zone if it has changed
* since we last checkpointed
*/
if (zp->z_type == Z_PRIMARY && zp->hasChanged)
zonedump(zp);
#endif ALLOW_UPDATES
zp->z_time = tt.tv_sec + zp->z_refresh;
}
/*
* Find when the next refresh needs to be and set
* interrupt time accordingly.
*/
if (next_refresh == 0 ||
(zp->z_time != 0 && next_refresh > zp->z_time))
next_refresh = zp->z_time;
}
/*
* Schedule the next call to this function.
* Don't visit any sooner than maint_interval.
*/
bzero((char *)&ival, sizeof (ival));
ival.it_value.tv_sec = next_refresh - tt.tv_sec;
if (ival.it_value.tv_sec < maint_interval)
ival.it_value.tv_sec = maint_interval;
(void) setitimer(ITIMER_REAL, &ival, (struct itimerval *)NULL);
#ifdef DEBUG
if (debug)
fprintf(ddt,"exit ns_maint() Next interrupt in %ld sec\n",
ival.it_value.tv_sec);
#endif
}
zoneref(zp)
struct zoneinfo *zp;
{
HEADER *hp;
u_short len;
u_long serial;
int s, n, l, tries;
int cnt, soacnt, error = 0;
int zone = zp - zones;
u_char *cp, *nmp, *eom;
u_char *tmp;
u_char buf[PACKETSZ];
char name[MAXDNAME], name2[MAXDNAME];
struct sockaddr_in sin;
struct zoneinfo zp_start, zp_finish;
struct itimerval ival;
struct itimerval zeroival;
extern struct sockaddr_in nsaddr;
extern int errno;
extern int read_interrupted;
extern int read_alarm();
struct sigvec sv, osv;
#ifdef DEBUG
if (debug)
fprintf(ddt,"zoneref() %s\n", zp->z_origin);
#endif
bzero((char *)&zeroival, sizeof(zeroival));
ival = zeroival;
ival.it_value.tv_sec = 30;
sv.sv_handler = read_alarm;
sv.sv_onstack = 0;
sv.sv_mask = ~0;
(void) sigvec(SIGALRM, &sv, &osv);
for( cnt = 0; cnt < zp->z_addrcnt; cnt++) {
error = 0;
bzero((char *)&sin, sizeof(sin));
sin.sin_family = AF_INET;
sin.sin_port = nsaddr.sin_port;
sin.sin_addr = zp->z_addr[cnt];
if ((s = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
syslog(LOG_ERR, "zoneref: socket: %m");
error++;
break;
}
#ifdef DEBUG
if (debug >= 2) {
fprintf(ddt,"connecting to server #%d %s, %d\n",
cnt+1, inet_ntoa(sin.sin_addr), ntohs(sin.sin_port));
}
#endif
if (connect(s, (struct sockaddr *)&sin, sizeof(sin)) < 0) {
(void) close(s);
error++;
#ifdef DEBUG
if (debug >= 2)
fprintf(ddt,"connect failed, errno %d\n", errno);
#endif
continue;
}
if ((n = res_mkquery(QUERY, zp->z_origin, C_IN,
T_SOA, (char *)NULL, 0, NULL, buf, sizeof(buf))) < 0) {
syslog(LOG_ERR, "zoneref: res_mkquery failed");
(void) close(s);
(void) sigvec(SIGALRM, &osv, (struct sigvec *)0);
return;
}
/*
* Send length & message for zone transfer
*/
if (writemsg(s, buf, n) < 0) {
(void) close(s);
error++;
#ifdef DEBUG
if (debug >= 2)
fprintf(ddt,"writemsg failed\n");
#endif
continue;
}
/*
* Get out your butterfly net and catch the SOA
*/
cp = buf;
l = sizeof(u_short);
read_interrupted = 0;
while (l > 0) {
(void) setitimer(ITIMER_REAL, &ival,
(struct itimerval *)NULL);
if ((n = recv(s, cp, l, 0)) > 0) {
cp += n;
l -= n;
} else {
if (errno == EINTR && !read_interrupted)
continue;
error++;
break;
}
}
(void) setitimer(ITIMER_REAL, &zeroival,
(struct itimerval *)NULL);
if (error) {
(void) close(s);
continue;
}
if ((len = htons(*(u_short *)buf)) == 0) {
(void) close(s);
if (zp->z_sysloged == 0)
syslog(LOG_ERR,
"no SOA from server %s, zone %s (len 0)\n",
inet_ntoa(sin.sin_addr), zp->z_origin);
continue;
}
l = len;
cp = buf;
while (l > 0) {
(void) setitimer(ITIMER_REAL, &ival,
(struct itimerval *)NULL);
if ((n = recv(s, cp, l, 0)) > 0) {
cp += n;
l -= n;
} else {
if (errno == EINTR && !read_interrupted)
continue;
error++;
break;
}
}
(void) setitimer(ITIMER_REAL, &zeroival,
(struct itimerval *)NULL);
if (error) {
(void) close(s);
continue;
}
#ifdef DEBUG
if (debug >= 3) {
fprintf(ddt,"len = %d\n", len);
fp_query(buf, ddt);
}
#endif DEBUG
zp_start = *zp;
tmp = buf + sizeof(HEADER);
eom = buf + len;
/* NEED TO CHECK MESSAGE LENGTH, ANCOUNT, AA */
tmp += dn_skipname(tmp, eom) + QFIXEDSZ;
tmp += dn_skipname(tmp, eom);
soa_zinfo(&zp_start, tmp, eom);
if (zp->z_serial >= zp_start.z_serial && zp->z_auth) {
#ifdef DEBUG
if (debug)
fprintf(ddt,"zoneref: up to date (%ld >= %ld)\n",
zp->z_serial, zp_start.z_serial);
#endif DEBUG
zp->z_lastupdate = tt.tv_sec;
zp->z_refresh = zp_start.z_refresh;
(void) close(s);
(void) sigvec(SIGALRM, &osv, (struct sigvec *)0);
if (zp->z_source) {
#if defined(SYSV)
struct utimbuf t;
t.actime = 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 /* SYSV */
}
return;
}
#ifdef DEBUG
if (debug)
fprintf(ddt,"zoneref: need xfer (%ld < %ld)\n",
zp->z_serial, zp_start.z_serial);
#endif DEBUG
hp = (HEADER *) buf;
soacnt = 0;
/* mark all existing RR's for zone as "old" */
mark_zone (hashtab, zone, 1);
for (tries = 0; ; tries++) {
if (soacnt == 0) {
/* delete unmarked (new) RR's for zone */
if (tries)
clean_zone (hashtab, zone, 0);
if ((n = res_mkquery(QUERY, zp->z_origin, C_IN,
T_AXFR, (char *)NULL, 0, NULL,
buf, sizeof(buf))) < 0) {
syslog(LOG_ERR, "zoneref: res_mkquery failed");
(void) close(s);
(void) sigvec(SIGALRM, &osv,
(struct sigvec *)0);
return;
}
/*
* Send length & message for zone transfer
*/
if (writemsg(s, buf, n) < 0) {
(void) close(s);
error++;
#ifdef DEBUG
if (debug >= 2)
fprintf(ddt,"writemsg failed\n");
#endif
break;
}
}
/*
* Receive length & response
*/
cp = buf;
l = sizeof(u_short);
while (l > 0) {
(void) setitimer(ITIMER_REAL, &ival,
(struct itimerval *)NULL);
if ((n = recv(s, cp, l, 0)) > 0) {
cp += n;
l -= n;
} else {
if (errno == EINTR && !read_interrupted)
continue;
error++;
break;
}
}
(void) setitimer(ITIMER_REAL, &zeroival,
(struct itimerval *)NULL);
if (error)
break;
if ((len = htons(*(u_short *)buf)) == 0)
break;
l = len;
cp = buf;
eom = buf + len;
while (l > 0) {
(void) setitimer(ITIMER_REAL, &ival,
(struct itimerval *)NULL);
if ((n = recv(s, cp, l, 0)) > 0) {
cp += n;
l -= n;
} else {
if (errno == EINTR && !read_interrupted)
continue;
error++;
break;
}
}
(void) setitimer(ITIMER_REAL, &zeroival,
(struct itimerval *)NULL);
if (error)
break;
#ifdef DEBUG
if (debug >= 3) {
fprintf(ddt,"len = %d\n", len);
fp_query(buf, ddt);
}
#endif
cp = buf + sizeof(HEADER);
if (hp->qdcount)
cp += dn_skipname(cp, eom) + QFIXEDSZ;
nmp = cp;
tmp = cp + dn_skipname(cp, eom);
n = doupdate(buf, sizeof(buf), cp, zone,
(struct databuf **)0, DB_NODATA);
if (cp + n != eom) {
#ifdef DEBUG
if (debug)
fprintf(ddt,"zoneref: doupdate failed (%d, %d)\n",
cp - buf, n);
#endif
error++;
break;
}
GETSHORT(n, tmp);
if (n == T_SOA) {
if (soacnt == 0) {
soacnt++;
dn_expand(buf, buf + 512, nmp, name,
sizeof(name));
tmp += 2 * sizeof(u_short)
+ sizeof(u_long);
tmp += dn_skipname(tmp, eom);
tmp += dn_skipname(tmp, eom);
GETLONG(serial, tmp);
#ifdef DEBUG
if (debug)
fprintf(ddt,
"first SOA for %s, serial %ld\n",
name, serial);
#endif DEBUG
continue;
}
dn_expand(buf, buf + 512, nmp, name2,
sizeof(name2));
if (strcasecmp(name, name2) !=0) {
#ifdef DEBUG
if (debug)
fprintf(ddt,
"extraneous SOA for %s\n",
name2);
#endif DEBUG
continue;
}
tmp -= sizeof(u_short);
soa_zinfo(&zp_finish, tmp, eom);
#ifdef DEBUG
if (debug)
fprintf(ddt,
"SOA, serial %ld\n", zp_finish.z_serial);
#endif DEBUG
if (serial != zp_finish.z_serial) {
soacnt = 0;
#ifdef DEBUG
if (debug)
fprintf(ddt,
"serial changed, restart\n");
#endif DEBUG
} else
break;
}
}
(void) close(s);
if ( error == 0) {
zp->z_refresh = zp_finish.z_refresh;
zp->z_retry = zp_finish.z_retry;
zp->z_expire = zp_finish.z_expire;
zp->z_minimum = zp_finish.z_minimum;
zp->z_serial = zp_finish.z_serial;
zp->z_lastupdate = tt.tv_sec;
zp->z_sysloged = 0;
zp->z_auth = 1;
/* delete previously marked RR's here, then dump */
clean_zone (hashtab, zone, 1);
zonedump(zp);
(void) sigvec(SIGALRM, &osv, (struct sigvec *)0);
return;
}
/* error: delete unmarked RR's here; remove old marks */
clean_zone (hashtab, zone, 0);
mark_zone (hashtab, zone, 0);
#ifdef DEBUG
if (debug >= 2)
fprintf(ddt,"error receiving zone transfer\n");
#endif
}
(void) sigvec(SIGALRM, &osv, (struct sigvec *)0);
/*
* Freedom at last!!
*
* The land where all repressed slaves dream of.
*
* Can't find a master to talk to.
* syslog it and hope we can find a master during next maintenance.
*/
if (error && (!zp->z_sysloged)) {
syslog(LOG_WARNING,
"zoneref: Masters for secondary zone %s unreachable",
zp->z_origin);
zp->z_sysloged++;
}
zp->z_refresh = zp->z_retry;
if (tt.tv_sec - zp->z_lastupdate > zp->z_expire)
zp->z_auth = 0;
}
#ifdef unused
/*
* Recursively delete all domains (except for root SOA records),
* starting from head of list pointed to by np.
*/
static DelDom(fnp, isroot)
struct namebuf *fnp;
int isroot;
{
register struct databuf *dp, *pdp = NULL;
register struct namebuf *np = fnp;
struct namebuf **npp, **nppend;
#ifdef DEBUG
if (debug >= 3)
fprintf(ddt, "DelDom('%s', %d)\n", fnp->n_dname, isroot);
#endif DEBUG
/* first do data records */
for (dp = np->n_data; dp != NULL; ) {
/* skip the root SOA record (marks end of data) */
if (isroot && dp->d_type == T_SOA) {
pdp = dp;
dp = dp->d_next;
continue;
}
dp = rm_datum(dp, np, pdp);
}
/* next do subdomains */
if (np->n_hash == NULL)
return;
npp = np->n_hash->h_tab;
nppend = npp + np->n_hash->h_size;
while (npp < nppend) {
for (np = *npp++; np != NULL; np = np->n_next) {
DelDom(np, 0);
}
}
}
#endif unused
#ifdef DEBUG
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[0] == '\0')
fprintf(ddt,"origin ='.'");
else
fprintf(ddt,"origin ='%s'", zp->z_origin);
fprintf(ddt,", type = %s", ZoneType);
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 = %ld\n", zp->z_serial);
fprintf(ddt,"z_time = %ld", zp->z_time);
fprintf(ddt,", now time : %ld sec", tt.tv_sec);
fprintf(ddt,", time left: %ld sec\n", zp->z_time - tt.tv_sec);
}
#endif DEBUG
/*
* New code added by Rich Wales (UCLA), October 1986:
*
* The following routines manipulate the d_mark field. When a zone
* is being refreshed, the old RR's are marked. This allows old RR's to
* be cleaned up after the new copy of the zone has been completely read
* -- or new RR's to be cleaned up if an error prevents transfer of a
* new zone copy.
*
*/
/*
* Set the "d_mark" field to on each RR in the zone "zone".
* Initially called with "htp" equal to "hashtab", this routine
* calls itself recursively in order to traverse all subdomains.
*/
mark_zone (htp, zone, flag)
struct hashbuf *htp;
register int zone;
register int flag;
{
register struct databuf *dp;
register struct namebuf *np;
register struct namebuf **npp, **nppend;
nppend = htp->h_tab + htp->h_size;
for (npp = htp->h_tab; npp < nppend; npp++) {
for (np = *npp; np != NULL; np = np->n_next) {
for (dp = np->n_data; dp != NULL; dp = dp->d_next)
if (dp->d_zone == zone)
dp->d_mark = flag;
if (np->n_hash != NULL) /* mark subdomains */
mark_zone (np->n_hash, zone, flag);
}
}
}
/*
* clean_zone (htp, zone, flag) --
* Delete all RR's in the zone "zone" whose "d_mark" values are
* equal to "flag". Originally called with "htp" equal to
* "hashtab", this routine calls itself recursively in order to
* traverse all subdomains.
*/
clean_zone (htp, zone, flag)
register struct hashbuf *htp;
register int zone;
register int flag;
{
register struct databuf *dp, *pdp;
register struct namebuf *np;
struct namebuf **npp, **nppend;
nppend = htp->h_tab + htp->h_size;
for (npp = htp->h_tab; npp < nppend; npp++) {
for (np = *npp; np != NULL; np = np->n_next) {
for (pdp = NULL, dp = np->n_data; dp != NULL; ) {
if (dp->d_zone == zone && dp->d_mark == flag)
dp = rm_datum(dp, np, pdp);
else {
pdp = dp;
dp = dp->d_next;
}
}
/* Call recursively to clean up subdomains. */
if (np->n_hash != NULL)
clean_zone (np->n_hash, zone, flag);
}
}
}