2.11BSD/src/usr.sbin/named/named/ns_main.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.
*/
#if !defined(lint) && defined(DOSCCS)
char copyright[] =
"@(#) Copyright (c) 1986 Regents of the University of California.\n\
All rights reserved.\n";
static char sccsid[] = "@(#)ns_main.c 4.30.1 (2.11BSD) 1996/11/16";
#endif /* not lint */
/*
* Internet Name server (see rfc883 & others).
*/
#include <sys/param.h>
#if defined(SYSV)
#include <fcntl.h>
#endif SYSV
#include <sys/file.h>
#include <sys/time.h>
#if !defined(SYSV)
#include <sys/wait.h>
#endif !SYSV
#include <sys/resource.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <net/if.h>
#include <stdio.h>
#include <syslog.h>
#include <errno.h>
#include <signal.h>
#include <netdb.h>
#include <arpa/nameser.h>
#include <arpa/inet.h>
#include <resolv.h>
#undef nsaddr /* XXX */
#include "ns.h"
#include "db.h"
#ifdef BOOTFILE /* default boot file */
char *bootfile = BOOTFILE;
#else
char *bootfile = "/etc/named.boot";
#endif
#ifdef DEBUGFILE /* default debug output file */
char *debugfile = DEBUGFILE;
#else
char *debugfile = "/usr/tmp/named.run";
#endif
#ifdef PIDFILE /* file to store current named PID */
char *PidFile = PIDFILE;
#else
char *PidFile = "/var/run/named.pid";
#endif
#ifndef FD_SET
#define NFDBITS 32
#define FD_SETSIZE 32
#define FD_SET(n, p) ((p)->fds_bits[(n)/NFDBITS] |= (1 << ((n) % NFDBITS)))
#define FD_CLR(n, p) ((p)->fds_bits[(n)/NFDBITS] &= ~(1 << ((n) % NFDBITS)))
#define FD_ISSET(n, p) ((p)->fds_bits[(n)/NFDBITS] & (1 << ((n) % NFDBITS)))
#define FD_ZERO(p) bzero((char *)(p), sizeof(*(p)))
#endif
FILE *fp; /* file descriptor for pid file */
#ifdef DEBUG
FILE *ddt;
#endif
int debug = 0; /* debugging flag */
int ds; /* datagram socket */
int read_interrupted = 0; /* flag for read timer */
int needreload = 0; /* received SIGHUP, need to reload db */
int needmaint = 0; /* need to call ns_maint()*/
int needToDoadump = 0; /* need to dump database */
int needToChkpt = 0; /* need to checkpoint cache */
int needStatsDump = 0; /* need to dump statistics */
#ifdef ALLOW_UPDATES
int needToExit = 0; /* need to exit (may need to doadump
* first, if database has changed since
* it was last dumped/booted). Gets
* set by shutdown signal handler
* (onintr)
*/
#endif ALLOW_UPDATES
int priming = 0; /* is cache being primed */
#ifdef SO_RCVBUF
int rbufsize = 8 * 1024; /* UDP recive buffer size */
#endif
struct qstream *streamq = QSTREAM_NULL; /* list of open streams */
struct qdatagram *datagramq = QDATAGRAM_NULL; /* list of datagram interfaces */
struct qdatagram *dqp, *sqp;
struct sockaddr_in nsaddr;
struct timeval tt;
struct netinfo *nettab = NULL;
struct netinfo *fnettab = NULL;
struct netinfo *onettab = NULL;
struct netinfo netloop;
short ns_port;
struct sockaddr_in from_addr; /* Source addr of last packet */
int from_len; /* Source addr size of last packet */
time_t boottime, resettime; /* Used by ns_stats */
fd_set mask; /* select mask of open descriptors */
u_long net_mask();
char **Argv = NULL; /* pointer to argument vector */
char *LastArg = NULL; /* end of argv */
extern int errno;
#if defined(SYSV)
getdtablesize()
{
return(FD_SETSIZE);
}
#endif SYSV
main(argc, argv, envp)
int argc;
char *argv[], *envp[];
{
register int n, udpcnt;
register char *arg;
register struct qstream *sp;
int vs;
int nfds;
int on = 1;
int rfd, size;
u_long lasttime, maxctime;
u_long nnn, nm;
char buf[BUFSIZ];
fd_set tmpmask;
struct timeval t, *tp;
struct qstream *candidate = QSTREAM_NULL;
struct ifconf ifc;
struct ifreq ifreq, *ifr;
struct netinfo *ntp;
struct netinfo *ntip;
struct netinfo *ontp;
struct netinfo *ontip;
extern int onintr(), maint_alarm(), reapchild(), setdumpflg(), onhup();
extern int setIncrDbgFlg(), setNoDbgFlg(), sigprof();
extern int setchkptflg(), setstatsflg();
extern struct qstream *sqadd();
extern struct qinfo *qhead;
extern char Version[];
ns_port = htons(NAMESERVER_PORT);
_res.options &= ~(RES_DEFNAMES | RES_DNSRCH | RES_RECURSE);
/*
** Save start and extent of argv for setproctitle.
*/
Argv = argv;
if (envp == 0 || *envp == 0)
envp = argv;
while (*envp)
envp++;
LastArg = envp[-1] + strlen(envp[-1]);
(void) umask(022);
while (--argc > 0) {
arg = *++argv;
if (*arg == '-') {
while (*++arg)
switch (*arg) {
case 'b':
if (--argc <= 0)
usage();
bootfile = *++argv;
break;
case 'd':
++argv;
if (*argv != 0) {
if (**argv == '-') {
argv--;
break;
}
debug = atoi(*argv);
--argc;
}
if (debug <= 0)
debug = 1;
setdebug(1);
break;
case 'p':
if (--argc <= 0)
usage();
ns_port = htons((u_short)atoi(*++argv));
break;
default:
usage();
}
} else
bootfile = *argv;
}
if (!debug) {
if (fork())
exit(0);
for (n = getdtablesize() - 1; n >= 0; n--)
(void) close(n);
(void) open("/dev/null", O_RDONLY);
(void) dup2(0, 1);
(void) dup2(0, 2);
n = open("/dev/tty", O_RDWR);
if (n > 0) {
#ifndef SYSV
(void) ioctl(n, TIOCNOTTY, (char *)NULL);
#else
setpgrp();
#endif
(void) close(n);
}
}
#ifdef DEBUG
else {
fprintf(ddt,"Debug turned ON, Level %d\n",debug);
fprintf(ddt,"Version = %s\t",Version);
fprintf(ddt,"bootfile = %s\n",bootfile);
}
#endif
#ifdef LOG_DAEMON
openlog("named", LOG_PID|LOG_CONS|LOG_NDELAY, LOG_DAEMON);
#else
openlog("named", LOG_PID);
#endif
/* tuck my process id away */
fp = fopen(PidFile, "w");
if (fp != NULL) {
fprintf(fp, "%d\n", getpid());
(void) fclose(fp);
}
syslog(LOG_NOTICE, "restarted\n");
nsaddr.sin_family = AF_INET;
nsaddr.sin_addr.s_addr = INADDR_ANY;
nsaddr.sin_port = ns_port;
/*
** Initialize and load database.
*/
gettime(&tt);
buildservicelist();
buildprotolist();
ns_init(bootfile);
time(&boottime);
resettime = boottime;
(void) signal(SIGALRM, maint_alarm);
(void) signal(SIGHUP, onhup);
#if defined(SYSV)
(void) signal(SIGCLD, reapchild);
#else
(void) signal(SIGCHLD, reapchild);
#endif SYSV
(void) signal(SIGPIPE, SIG_IGN);
(void) signal(SIGSYS, sigprof);
(void) signal(SIGINT, setdumpflg);
(void) signal(SIGQUIT, setchkptflg);
(void) signal(SIGIOT, setstatsflg);
#ifdef ALLOW_UPDATES
/* Catch SIGTERM so we can dump the database upon shutdown if it
has changed since it was last dumped/booted */
(void) signal(SIGTERM, onintr);
#endif ALLOW_UPDATES
#if defined(SIGUSR1) && defined(SIGUSR2)
(void) signal(SIGUSR1, setIncrDbgFlg);
(void) signal(SIGUSR2, setNoDbgFlg);
#else SIGUSR1&&SIGUSR2
(void) signal(SIGEMT, setIncrDbgFlg);
(void) signal(SIGFPE, setNoDbgFlg);
#endif SIGUSR1&&SIGUSR2
#ifdef DEBUG
if (debug) {
fprintf(ddt,"database initialized\n");
}
#endif
/*
** Open stream port.
*/
if ((vs = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
syslog(LOG_ERR, "socket(SOCK_STREAM): %m");
exit(1);
}
(void)setsockopt(vs, SOL_SOCKET, SO_REUSEADDR, (char *)&on, sizeof(on));
if (bind(vs, (struct sockaddr *)&nsaddr, sizeof(nsaddr))) {
syslog(LOG_ERR, "bind(vs, %s[%d]): %m",
inet_ntoa(nsaddr.sin_addr), ntohs(nsaddr.sin_port));
exit(1);
}
ifc.ifc_len = sizeof(buf);
ifc.ifc_buf = buf;
if (ioctl(vs, SIOCGIFCONF, (char *)&ifc) < 0) {
syslog(LOG_ERR, "get interface configuration: %m");
exit(1);
}
n = ifc.ifc_len/sizeof(struct ifreq);
ntp = NULL;
for (ifr = ifc.ifc_req; n > 0; n--, ifr++) {
int dup_addr;
if (ifr->ifr_addr.sa_family != AF_INET)
continue;
ifreq = *ifr;
if (ioctl(vs, SIOCGIFFLAGS, (char *)&ifreq) < 0) {
syslog(LOG_ERR, "get interface flags: %m");
continue;
}
if ((ifreq.ifr_flags & IFF_UP) == 0)
continue;
if (ioctl(vs, SIOCGIFADDR, (char *)&ifreq) < 0) {
syslog(LOG_ERR, "get interface addr: %m");
continue;
}
/* build datagram queue */
if ((dqp = (struct qdatagram *)calloc(1,
sizeof(struct qdatagram))) == NULL) {
#ifdef DEBUG
if (debug >= 5)
fprintf(ddt,"main: malloc error\n");
#endif
syslog(LOG_ERR, "main: Out Of Memory");
exit(12);
}
dqp->dq_next = datagramq;
dqp->dq_addr = ((struct sockaddr_in *)&ifreq.ifr_addr)->sin_addr;
/*
* look for an already existing source interface address. If
* the machine has multiple point to point interfaces, then
* the local address may appear more than once.
*/
dup_addr = 0;
for (sqp=datagramq; sqp != NULL; sqp = sqp->dq_next)
if (dqp->dq_addr.s_addr == sqp->dq_addr.s_addr) {
dup_addr = 1;
break;
}
if (!dup_addr)
datagramq = dqp;
else {
#ifdef DEBUG
if (debug)
fprintf(ddt, "main: dup interface address %s on %s\n",
inet_ntoa(dqp->dq_addr), ifreq.ifr_name);
#endif
free((char *) dqp);
}
if (ntp == NULL)
ntp = (struct netinfo *)malloc(sizeof(struct netinfo));
ntp->my_addr =
((struct sockaddr_in *)&ifreq.ifr_addr)->sin_addr;
#ifdef SIOCGIFNETMASK
if (ioctl(vs, SIOCGIFNETMASK, (char *)&ifreq) < 0) {
syslog(LOG_ERR, "get netmask: %m");
continue;
}
ntp->mask = ((struct sockaddr_in *)
&ifreq.ifr_addr)->sin_addr.s_addr;
#else
/* 4.2 does not support subnets */
ntp->mask = net_mask(ntp->my_addr);
#endif
if (ioctl(vs, SIOCGIFFLAGS, (char *)&ifreq) < 0) {
syslog(LOG_ERR, "get interface flags: %m");
continue;
}
#ifdef IFF_LOOPBACK
if ((ifreq.ifr_flags & IFF_LOOPBACK))
#else
/* test against 127.0.0.1 (yuck!!) */
if (ntp->my_addr.s_addr == htonl(0x7F000001))
#endif
{
netloop.my_addr = ntp->my_addr;
netloop.mask = 0xffffffff;
netloop.net = ntp->my_addr.s_addr;
netloop.next = NULL;
#ifdef DEBUG
if (debug)
fprintf(ddt,"loopback address: x%lx\n",
netloop.my_addr.s_addr);
#endif DEBUG
continue;
} else if ((ifreq.ifr_flags & IFF_POINTOPOINT)) {
if (ioctl(vs, SIOCGIFDSTADDR, (char *)&ifreq) < 0) {
syslog(LOG_ERR, "get dst addr: %m");
continue;
}
ntp->mask = 0xffffffff;
ntp->net = ((struct sockaddr_in *)
&ifreq.ifr_addr)->sin_addr.s_addr;
} else {
ntp->net = ntp->mask & ntp->my_addr.s_addr;
}
ntp->next = NULL;
if (nettab == NULL)
nettab = ntip = ntp;
else {
ntip->next = ntp;
ntip = ntp;
}
ntp = NULL;
}
if (ntp)
(void) free((char *)ntp);
/*
* Create separate qdatagram structure for socket
* wildcard address.
*/
if ((dqp = (struct qdatagram *)calloc(1, sizeof(struct qdatagram)))
== NULL) {
#ifdef DEBUG
if (debug >= 5)
fprintf(ddt,"main: malloc error\n");
#endif
syslog(LOG_ERR, "main: Out Of Memory");
exit(12);
}
dqp->dq_next = datagramq;
datagramq = dqp;
dqp->dq_addr.s_addr = INADDR_ANY;
/*
* Compute other networks for sorting based on network configuration
*/
ontp = NULL;
for (ntp = nettab; ntp != NULL; ntp = ntp->next) {
nm = net_mask(ntp->my_addr);
if (nm != ntp->mask) {
nnn = ntp->my_addr.s_addr & nm;
for (ontp=onettab; ontp != NULL; ontp=ontp->next) {
if ((ontp->net == nnn) &&
(ontp->mask == nm))
goto outerloop;
ontip = ontp;
}
ontp = (struct netinfo *)
malloc(sizeof(struct netinfo));
ontp->net = nnn;
ontp->mask = nm;
ontp->my_addr = ntp->my_addr;
ontp->next = NULL;
if (onettab == NULL )
onettab = ontp;
else
ontip->next = ontp;
}
outerloop:
;
}
/*
* Merge sort list from network configuration
* with list we computed from network configuration
*/
for (ntp = nettab; ntp != NULL; ntp = ntp->next){
if (ntp->next == NULL) {
ntp->next = onettab;
break;
}
}
/*
* Merge sort list from boot file with list from
* network configuration
*/
for (ntp = nettab; ntp != NULL; ntp = ntp->next) {
for (ontp = fnettab; ontp != NULL; ontp = ontp->next) {
if ((ontp->mask == ntp->mask) && (ontp->net == ntp->net)) {
if( fnettab == ontp ) {
ontip = ontp;
fnettab = ontp->next;
free((char *)ontip);
break;
} else {
for (ontip = fnettab; ontip != NULL;ontip = ontip->next)
if (ontip->next == ontp) break;
ontip->next = ontp->next;
free((char *)ontp);
ontp = ontip;
break;
}
}
}
if (ntp->next == NULL)
break;
}
ntp->next = fnettab;
#ifdef DEBUG
if (debug)
for (ntp = nettab; ntp != NULL; ntp = ntp->next) {
fprintf(ddt,"net x%lx mask x%lx",
ntohl(ntp->net), ntohl(ntp->mask));
fprintf(ddt," my_addr x%lx", ntohl(ntp->my_addr.s_addr));
fprintf(ddt," %s\n", inet_ntoa(ntp->my_addr));
}
#endif DEBUG
(void) listen(vs, 5);
/*
* Open datagram ports for each interface
* (the first is un-addressed datagram port).
*/
for (dqp = datagramq; dqp != QDATAGRAM_NULL; dqp = dqp->dq_next) {
nsaddr.sin_addr = dqp->dq_addr;
if ((dqp->dq_dfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
syslog(LOG_ERR, "socket(SOCK_DGRAM): %m");
exit(1);
}
#ifdef DEBUG
if (debug)
fprintf(ddt,"dqp->dq_addr %s d_dfd %d\n",
inet_ntoa(dqp->dq_addr), dqp->dq_dfd);
#endif DEBUG
(void)setsockopt(dqp->dq_dfd, SOL_SOCKET, SO_REUSEADDR,
(char *)&on, sizeof(on));
#ifdef SO_RCVBUF
(void)setsockopt(dqp->dq_dfd, SOL_SOCKET, SO_RCVBUF,
(char *)&rbufsize, sizeof(rbufsize));
#endif SO_RCVBUF
(void) fcntl(dqp->dq_dfd, F_SETFL, FNDELAY);
/*
* NOTE: Some versions of SunOS have problems with the following
* call to bind. Bind still seems to function on these systems
* if you comment out the exit inside the if. This may cause
* Suns with multiple interfaces to reply strangely.
*/
if (bind(dqp->dq_dfd, (struct sockaddr *)&nsaddr, sizeof(nsaddr))) {
syslog(LOG_ERR, "bind(dfd %d, %s[%d]): %m",
dqp->dq_dfd, inet_ntoa(nsaddr.sin_addr),
ntohs(nsaddr.sin_port));
#if !defined(sun)
exit(1);
#endif
}
}
ds = datagramq->dq_dfd;
t.tv_usec = 0;
#ifdef DEBUG
if (debug)
fprintf(ddt,"Ready to answer queries.\n");
#endif
prime_cache();
nfds = getdtablesize(); /* get the number of file descriptors */
if (nfds > FD_SETSIZE) {
nfds = FD_SETSIZE; /* Bulletproofing */
syslog(LOG_ERR, "Return from getdtablesize() > FD_SETSIZE");
#ifdef DEBUG
if (debug)
fprintf(ddt,"Return from getdtablesize() > FD_SETSIZE\n");
#endif
}
FD_ZERO(&mask);
FD_SET(vs, &mask);
FD_SET(ds, &mask);
for (dqp = datagramq; dqp != QDATAGRAM_NULL; dqp = dqp->dq_next)
FD_SET(dqp->dq_dfd, &mask);
for (;;) {
#ifdef ALLOW_UPDATES
if (needToExit) {
struct zoneinfo *zp;
sigblock(~0L); /*
* Block all blockable signals
* to ensure a consistant
* state during final dump
*/
#ifdef DEBUG
if (debug)
fprintf(ddt, "Received shutdown signal\n");
#endif DEBUG
for (zp = zones; zp < &zones[nzones]; zp++) {
if (zp->hasChanged)
zonedump(zp);
}
exit(0);
}
#endif ALLOW_UPDATES
if(needreload) {
needreload = 0;
db_reload();
}
#ifdef STATS
if(needStatsDump) {
needStatsDump = 0;
ns_stats();
}
#endif STATS
if(needmaint) {
needmaint = 0;
ns_maint();
}
if(needToChkpt) {
needToChkpt = 0;
doachkpt();
}
if(needToDoadump) {
needToDoadump = 0;
doadump();
}
/*
** Wait until a query arrives
*/
if (retryqp != NULL) {
gettime(&tt);
t.tv_sec = (long) retryqp->q_time - tt.tv_sec;
if (t.tv_sec <= 0) {
retry(retryqp);
continue;
}
tp = &t;
} else
tp = NULL;
tmpmask = mask;
n = select(nfds, &tmpmask, (fd_set *)NULL, (fd_set *)NULL, tp);
if (n < 0) {
if (errno == EINTR)
continue;
syslog(LOG_ERR, "select: %m");
#ifdef DEBUG
if (debug)
fprintf(ddt,"select error\n");
#endif
;
}
if (n == 0)
continue;
for (dqp = datagramq; dqp != QDATAGRAM_NULL;
dqp = dqp->dq_next) {
if (FD_ISSET(dqp->dq_dfd, &tmpmask))
for(udpcnt = 0; udpcnt < 25; udpcnt++) {
from_len = sizeof(from_addr);
if ((n = recvfrom(dqp->dq_dfd, buf, sizeof(buf), 0,
(struct sockaddr *)&from_addr, &from_len)) < 0)
{
if ((n == -1) && (errno == EWOULDBLOCK))
break;
syslog(LOG_WARNING, "recvfrom: %m");
break;
}
#ifdef STATS
stats[S_INPKTS].cnt++;
#endif
#ifdef DEBUG
if (debug)
fprintf(ddt,
"\ndatagram from %s port %d, fd %d, len %d\n",
inet_ntoa(from_addr.sin_addr),
ntohs(from_addr.sin_port), ds, n);
if (debug >= 10)
fp_query(buf, ddt);
#endif
/*
* Consult database to get the answer.
*/
gettime(&tt);
ns_req(buf, n, PACKETSZ, QSTREAM_NULL, &from_addr,
dqp->dq_dfd);
}
}
/*
** Process stream connection
*/
if (FD_ISSET(vs, &tmpmask)) {
from_len = sizeof(from_addr);
rfd = accept(vs, (struct sockaddr *)&from_addr, &from_len);
gettime(&tt);
if (rfd < 0 && errno == EMFILE && streamq != NULL) {
maxctime = 0;
candidate = QSTREAM_NULL;
for (sp = streamq; sp != QSTREAM_NULL;
sp = sp->s_next) {
if (sp->s_refcnt != 0)
continue;
lasttime = tt.tv_sec - sp->s_time;
if (lasttime >= 900)
sqrm(sp, &mask);
else if (lasttime > maxctime) {
candidate = sp;
maxctime = lasttime;
}
}
rfd = accept(vs, (struct sockaddr *)&from_addr, &from_len);
if ((rfd < 0) && (errno == EMFILE) &&
candidate != QSTREAM_NULL) {
sqrm(candidate, &mask);
rfd = accept(vs, (struct sockaddr *)&from_addr, &from_len);
}
}
if (rfd < 0) {
syslog(LOG_WARNING, "accept: %m");
continue;
}
(void) fcntl(rfd, F_SETFL, FNDELAY);
(void) setsockopt(rfd, SOL_SOCKET, SO_KEEPALIVE,
(char *)&on, sizeof(on));
if ((sp = sqadd()) == QSTREAM_NULL) {
(void) close(rfd);
continue;
}
sp->s_rfd = rfd; /* stream file descriptor */
sp->s_size = -1; /* amount of data to receive */
gettime(&tt);
sp->s_time = tt.tv_sec; /* last transaction time */
sp->s_from = from_addr; /* address to respond to */
sp->s_bufsize = 0;
sp->s_bufp = (char *)&sp->s_tempsize;
sp->s_refcnt = 0;
FD_SET(rfd, &mask);
FD_SET(rfd, &tmpmask);
#ifdef DEBUG
if (debug) {
fprintf(ddt,
"\nTCP connection from %s port %d (fd %d)\n",
inet_ntoa(sp->s_from.sin_addr),
ntohs(sp->s_from.sin_port), rfd);
}
#endif
}
#ifdef DEBUG
if (debug > 2 && streamq)
fprintf(ddt,"streamq = x%x\n",streamq);
#endif
if (streamq != NULL) {
for (sp = streamq; sp != QSTREAM_NULL; sp = sp->s_next)
if (FD_ISSET(sp->s_rfd, &tmpmask)) {
#ifdef DEBUG
if (debug > 5) {
fprintf(ddt,
"sp x%x rfd %d size %d time %ld ",
sp, sp->s_rfd, sp->s_size,
sp->s_time );
fprintf(ddt," next x%x \n", sp->s_next );
fprintf(ddt,"\tbufsize %d",sp->s_bufsize);
fprintf(ddt," buf x%x ",sp->s_buf);
fprintf(ddt," bufp x%x\n",sp->s_bufp);
}
#endif DEBUG
if (sp->s_size < 0) {
size = sizeof(u_short) -
(sp->s_bufp - (char *)&sp->s_tempsize);
while (size > 0 &&
(n = read(sp->s_rfd, sp->s_bufp, size)) > 0){
sp->s_bufp += n;
size -= n;
}
if ((n == -1) && (errno == EWOULDBLOCK))
continue;
if (n <= 0) {
sp->s_refcnt = 0;
sqrm(sp, &mask);
continue;
}
if ((sp->s_bufp - (char *)&sp->s_tempsize) ==
sizeof(u_short)) {
sp->s_size = htons(sp->s_tempsize);
if (sp->s_bufsize == 0) {
if ( (sp->s_buf = malloc(BUFSIZ))
== NULL) {
sp->s_buf = buf;
sp->s_size = sizeof(buf);
} else {
sp->s_bufsize = BUFSIZ;
}
}
if (sp->s_size > sp->s_bufsize &&
sp->s_bufsize != 0) {
if ((sp->s_buf = realloc(
(char *)sp->s_buf,
(unsigned)sp->s_size)) == NULL){
sp->s_buf = buf;
sp->s_bufsize = 0;
sp->s_size = sizeof(buf);
} else {
sp->s_bufsize = sp->s_size;
}
}
sp->s_bufp = sp->s_buf;
}
}
gettime(&tt);
sp->s_time = tt.tv_sec;
while (sp->s_size > 0 &&
(n = read(sp->s_rfd, sp->s_bufp, sp->s_size)) > 0)
{
sp->s_bufp += n;
sp->s_size -= n;
}
/*
* we don't have enough memory for the query.
* if we have a query id, then we will send an
* error back to the user.
*/
if (sp->s_bufsize == 0 &&
(sp->s_bufp - sp->s_buf > sizeof(u_short))) {
HEADER *hp;
hp = (HEADER *)sp->s_buf;
hp->qr = 1;
hp->ra = 1;
hp->ancount = 0;
hp->qdcount = 0;
hp->nscount = 0;
hp->arcount = 0;
hp->rcode = SERVFAIL;
(void) writemsg(sp->s_rfd, sp->s_buf,
sizeof(HEADER));
continue;
}
if ((n == -1) && (errno == EWOULDBLOCK))
continue;
if (n <= 0) {
sp->s_refcnt = 0;
sqrm(sp, &mask);
continue;
}
/*
* Consult database to get the answer.
*/
if (sp->s_size == 0) {
sp->s_refcnt++;
ns_req(sp->s_buf,
sp->s_bufp - sp->s_buf,
sp->s_bufsize, sp,
&sp->s_from, -1);
sp->s_bufp = (char *)&sp->s_tempsize;
sp->s_size = -1;
continue;
}
}
}
}
/* NOTREACHED */
}
usage()
{
fprintf(stderr, "Usage: named [-d #] [-p port] [{-b} bootfile]\n");
exit(1);
}
/*
** Set flag saying to reload database upon receiving SIGHUP.
** Must make sure that someone isn't walking through a data
** structure at the time.
*/
onhup()
{
#if defined(SYSV)
(void)signal(SIGHUP, onhup);
#endif SYSV
needreload = 1;
}
/*
** Set flag saying to call ns_maint()
** Must make sure that someone isn't walking through a data
** structure at the time.
*/
maint_alarm()
{
#if defined(SYSV)
(void)signal(SIGALRM, maint_alarm);
#endif SYSV
needmaint = 1;
}
#ifdef ALLOW_UPDATES
/*
* Signal handler to schedule shutdown. Just set flag, to ensure a consistent
* state during dump.
*/
onintr()
{
needToExit = 1;
}
#endif ALLOW_UPDATES
/*
* Signal handler to schedule a data base dump. Do this instead of dumping the
* data base immediately, to avoid seeing it in a possibly inconsistent state
* (due to updates), and to avoid long disk I/O delays at signal-handler
* level
*/
int setdumpflg()
{
#if defined(SYSV)
(void)signal(SIGINT, setdumpflg);
#endif SYSV
needToDoadump = 1;
}
/*
** Set flag saying to read was interrupted
** used for a read timer
*/
read_alarm()
{
extern int read_interrupted;
read_interrupted = 1;
}
reapchild()
{
#if defined(SYSV)
(void)wait(0);
(void)signal(SIGCLD, reapchild);
#else
union wait status;
while ((wait3(&status, WNOHANG, (struct rusage *)NULL)) > 0)
;
#endif SYSV
}
/*
** Turn on or off debuging by open or closeing the debug file
*/
setdebug(code)
int code;
{
#if defined(lint) && !defined(DEBUG)
code = code;
#endif
#ifdef DEBUG
if (code) {
ddt = freopen(debugfile, "w+", stderr);
if ( ddt == NULL)
syslog(LOG_WARNING, "can't open debug file: %m");
else {
#if defined(SYSV)
setvbuf(ddt, NULL, _IOLBF, BUFSIZ);
#else
setlinebuf(ddt);
#endif
(void) fcntl(fileno(ddt), F_SETFL, FAPPEND);
}
}
else {
if (ddt) {
fprintf(ddt,"Debug turned OFF, Level %d\n",debug);
(void) fclose(ddt);
}
debug = 0;
}
#endif
}
/*
** Catch a special signal and set debug level.
**
** If debuging is off then turn on debuging else increment the level.
**
** Handy for looking in on long running name servers.
*/
setIncrDbgFlg()
{
#if defined(SYSV)
(void)signal(SIGUSR1, setIncrDbgFlg);
#endif SYSV
#ifdef DEBUG
if (debug == 0) {
debug++;
setdebug(1);
}
else {
debug++;
}
fprintf(ddt,"Debug turned ON, Level %d\n",debug);
#endif
}
/*
** Catch a special signal to turn off debugging
*/
setNoDbgFlg()
{
#if defined(SYSV)
(void)signal(SIGUSR2, setNoDbgFlg);
#endif SYSV
setdebug(0);
}
/*
** Set flag for statistics dump
*/
setstatsflg()
{
#if defined(SYSV)
(void)signal(SIGIOT, setstatsflg);
#endif SYSV
needStatsDump = 1;
}
int setchkptflg()
{
#if defined(SYSV)
(void)signal(SIGQUIT, setchkptflg);
#endif SYSV
needToChkpt = 1;
}
/*
** Catch a special signal SIGSYS
**
** this is setup to fork and exit to drop to /usr/tmp/gmon.out
** and keep the server running
*/
sigprof()
{
#if defined(SYSV)
(void)signal(SIGSYS, sigprof);
#endif SYSV
#ifdef DEBUG
if (debug)
fprintf(ddt,"sigprof()\n");
#endif
if ( fork() == 0)
{
(void) chdir("/usr/tmp");
exit(1);
}
}
/*
** Routines for managing stream queue
*/
struct qstream *
sqadd()
{
register struct qstream *sqp;
if ((sqp = (struct qstream *)calloc(1, sizeof(struct qstream)))
== NULL ) {
#ifdef DEBUG
if (debug >= 5)
fprintf(ddt,"sqadd: malloc error\n");
#endif
syslog(LOG_ERR, "sqadd: Out Of Memory");
return(QSTREAM_NULL);
}
#ifdef DEBUG
if (debug > 3)
fprintf(ddt,"sqadd(x%x)\n", sqp);
#endif
sqp->s_next = streamq;
streamq = sqp;
return(sqp);
}
sqrm(qp, mask)
register struct qstream *qp;
fd_set *mask;
{
register struct qstream *qsp;
#ifdef DEBUG
if (debug > 1) {
fprintf(ddt,"sqrm(%x, %d ) rfcnt=%d\n",
qp, qp->s_rfd, qp->s_refcnt);
}
#endif
if (qp->s_refcnt != 0)
return;
if (qp->s_bufsize != 0)
(void) free(qp->s_buf);
FD_CLR(qp->s_rfd, mask);
(void) close(qp->s_rfd);
if (qp == streamq) {
streamq = qp->s_next;
} else {
for (qsp = streamq; qsp->s_next != qp; qsp = qsp->s_next)
;
qsp->s_next = qp->s_next;
}
(void)free((char *)qp);
}
sqflush()
{
register struct qstream *sp, *spnext;
for (sp = streamq; sp != QSTREAM_NULL; sp = spnext) {
sp->s_refcnt = 0;
spnext = sp->s_next;
sqrm(sp, &mask);
}
}
setproctitle(a, s)
char *a;
int s;
{
int size;
register char *cp;
struct sockaddr_in sin;
char buf[80];
cp = Argv[0];
size = sizeof(sin);
if (getpeername(s, (struct sockaddr *)&sin, &size) == 0)
(void) sprintf(buf, "-%s [%s]", a, inet_ntoa(sin.sin_addr));
else {
syslog(LOG_DEBUG, "getpeername: %m");
(void) sprintf(buf, "-%s", a);
}
(void) strncpy(cp, buf, LastArg - cp);
cp += strlen(cp);
while (cp < LastArg)
*cp++ = ' ';
}
u_long
net_mask(in)
struct in_addr in;
{
register u_long i = ntohl(in.s_addr);
if (IN_CLASSA(i))
return (htonl(IN_CLASSA_NET));
else if (IN_CLASSB(i))
return (htonl(IN_CLASSB_NET));
else
return (htonl(IN_CLASSC_NET));
}
gettime(ttp)
struct timeval *ttp;
{
if (gettimeofday(ttp, (struct timezone *)0) < 0)
syslog(LOG_ERR, "gettimeofday failed: %m");
return;
}