예제 #1
0
파일: dns.c 프로젝트: Earnestly/plan9
void
main(int argc, char *argv[])
{
	int kid, pid;
	char servefile[Maxpath], ext[Maxpath];
	Dir *dir;

	setnetmtpt(mntpt, sizeof mntpt, nil);
	ext[0] = 0;
	ARGBEGIN{
	case 'a':
		maxage = atol(EARGF(usage()));
		if (maxage <= 0)
			maxage = Defmaxage;
		break;
	case 'd':
		debug = 1;
		traceactivity = 1;
		break;
	case 'f':
		dbfile = EARGF(usage());
		break;
	case 'F':
		cfg.justforw = cfg.resolver = 1;
		break;
	case 'n':
		sendnotifies = 1;
		break;
	case 'N':
		target = atol(EARGF(usage()));
		if (target < 1000)
			target = 1000;
		break;
	case 'o':
		cfg.straddle = 1;	/* straddle inside & outside networks */
		break;
	case 'r':
		cfg.resolver = 1;
		break;
	case 'R':
		norecursion = 1;
		break;
	case 's':
		cfg.serve = 1;		/* serve network */
		cfg.cachedb = 1;
		break;
	case 't':
		testing = 1;
		break;
	case 'T':
		addforwtarg(EARGF(usage()));
		break;
	case 'x':
		setnetmtpt(mntpt, sizeof mntpt, EARGF(usage()));
		setext(ext, sizeof ext, mntpt);
		break;
	case 'z':
		zonerefreshprogram = EARGF(usage());
		break;
	default:
		usage();
		break;
	}ARGEND
	if(argc != 0)
		usage();

	if(testing)
		mainmem->flags |= POOL_NOREUSE | POOL_ANTAGONISM;
	mainmem->flags |= POOL_ANTAGONISM;
	rfork(RFREND|RFNOTEG);

	cfg.inside = (*mntpt == '\0' || strcmp(mntpt, "/net") == 0);

	/* start syslog before we fork */
	fmtinstall('F', fcallfmt);
	dninit();
	/* this really shouldn't be fatal */
	if(myipaddr(ipaddr, mntpt) < 0)
		sysfatal("can't read my ip address");
	dnslog("starting %s%sdns %s%s%son %I's %s",
		(cfg.straddle? "straddling ": ""),
		(cfg.cachedb? "caching ": ""),
		(cfg.serve?   "udp server ": ""),
		(cfg.justforw? "forwarding-only ": ""),
		(cfg.resolver? "resolver ": ""), ipaddr, mntpt);

	opendatabase();
	now = time(nil);		/* open time files before we fork */
	nowns = nsec();

	snprint(servefile, sizeof servefile, "#s/dns%s", ext);
	dir = dirstat(servefile);
	if (dir)
		sysfatal("%s exists; another dns instance is running",
			servefile);
	free(dir);

	/* don't unmount here; could deadlock */
//	while (unmount(servefile, mntpt) >= 0)
//		;
	mountinit(servefile, mntpt);	/* forks, parent exits */

	srand(now*getpid());
	db2cache(1);
//	dnageallnever();

	if (cfg.straddle && !seerootns())
		dnslog("straddle server misconfigured; can't resolve root name servers");
	/*
	 * fork without sharing heap.
	 * parent waits around for child to die, then forks & restarts.
	 * child may spawn udp server, notify procs, etc.; when it gets too
	 * big or too old, it kills itself and any children.
	 *
	 * /srv/dns remains open and valid, but /net/dns was only mounted in
	 * a child's separate namespace from 9p service, to avoid a deadlock
	 * from serving our own namespace, so we must remount it upon restart,
	 * in a separate process and namespace.
	 */
	for (;;) {
		start = time(nil);
		/* don't unmount here; could deadlock */
//		unmount(servefile, mntpt);
		kid = rfork(RFPROC|RFFDG|RFNOTEG|RFNAMEG);
		switch (kid) {
		case -1:
			sysfatal("fork failed: %r");
		case 0:
			if(cfg.serve)
				dnudpserver(mntpt);
			if(sendnotifies)
				notifyproc();
			io();		/* serve 9p; return implies restart */
			_exits("restart");
		}
		sleep(1000);	/* wait for 9p service to start */
		justremount(servefile, mntpt);
		while ((pid = waitpid()) != kid && pid != -1)
			continue;
		dnslog("restarting");
	}
}
예제 #2
0
파일: dnstcp.c 프로젝트: dancrossnyc/harvey
void
main(int argc, char *argv[])
{
	int len, rcode;
	char tname[32];
	char *err, *ext = "";
	unsigned char buf[64*1024], callip[IPaddrlen];
	DNSmsg reqmsg, repmsg;
	Request req;

	alarm(2*60*1000);
	cfg.cachedb = 1;
	ARGBEGIN{
	case 'd':
		debug++;
		break;
	case 'f':
		dbfile = EARGF(usage());
		break;
	case 'r':
		cfg.resolver = 1;
		break;
	case 'R':
		norecursion = 1;
		break;
	case 'x':
		ext = EARGF(usage());
		break;
	default:
		usage();
		break;
	}ARGEND

	if(debug < 2)
		debug = 0;

	if(argc > 0)
		getcaller(argv[0]);

	cfg.inside = 1;
	dninit();

	snprint(mntpt, sizeof mntpt, "/net%s", ext);
	if(myipaddr(ipaddr, mntpt) < 0)
		sysfatal("can't read my ip address");
	dnslog("dnstcp call from %s to %I", caller, ipaddr);
	memset(callip, 0, sizeof callip);
	parseip(callip, caller);

	db2cache(1);

	memset(&req, 0, sizeof req);
	setjmp(req.mret);
	req.isslave = 0;
	procsetname("main loop");

	/* loop on requests */
	for(;; putactivity(0)){
		now = time(nil);
		memset(&repmsg, 0, sizeof repmsg);
		len = readmsg(0, buf, sizeof buf);
		if(len <= 0)
			break;

		getactivity(&req, 0);
		req.aborttime = timems() + S2MS(15*Min);
		rcode = 0;
		memset(&reqmsg, 0, sizeof reqmsg);
		err = convM2DNS(buf, len, &reqmsg, &rcode);
		if(err){
			dnslog("server: input error: %s from %s", err, caller);
			free(err);
			break;
		}
		if (rcode == 0) {
			if(reqmsg.qdcount < 1){
				dnslog("server: no questions from %s", caller);
				break;
			} else if(reqmsg.flags & Fresp){
				dnslog("server: reply not request from %s",
					caller);
				break;
			} else if((reqmsg.flags & Omask) != Oquery){
				dnslog("server: op %d from %s",
					reqmsg.flags & Omask, caller);
				break;
			}
		}
		if(debug)
			dnslog("[%d] %d: serve (%s) %d %s %s",
				getpid(), req.id, caller,
				reqmsg.id, reqmsg.qd->owner->name,
				rrname(reqmsg.qd->type, tname, sizeof tname));

		/* loop through each question */
		while(reqmsg.qd)
			if(reqmsg.qd->type == Taxfr)
				dnzone(&reqmsg, &repmsg, &req);
			else {
				dnserver(&reqmsg, &repmsg, &req, callip, rcode);
				reply(1, &repmsg, &req);
				rrfreelist(repmsg.qd);
				rrfreelist(repmsg.an);
				rrfreelist(repmsg.ns);
				rrfreelist(repmsg.ar);
			}
		rrfreelist(reqmsg.qd);		/* qd will be nil */
		rrfreelist(reqmsg.an);
		rrfreelist(reqmsg.ns);
		rrfreelist(reqmsg.ar);

		if(req.isslave){
			putactivity(0);
			_exits(0);
		}
	}
	refreshmain(mntpt);
}
예제 #3
0
파일: dns.c 프로젝트: 00001/plan9port
void
threadmain(int argc, char *argv[])
{
	int serveudp, servetcp;
	char *service;

	serveudp = 0;
	servetcp = 0;
	service = "dns";
	ARGBEGIN{
	case 'd':
		debug = 1;
		traceactivity = 1;
		break;
	case 'f':
		dbfile = EARGF(usage());
		break;
	case 'x':
		service = EARGF(usage());
		break;
	case 'r':
		resolver = 1;
		break;
	case 's':
		serveudp = 1;
		cachedb = 1;
		break;
	case 't':
		servetcp = 1;
		cachedb = 1;
		break;
	case 'a':
		maxage = atoi(EARGF(usage()));
		break;
	case 'z':
		zonerefreshprogram = EARGF(usage());
		break;
	case 'n':
		sendnotifies = 1;
		break;
	case 'U':
		udpaddr = estrdup(netmkaddr(EARGF(usage()), "udp", "domain"));
		break;
	case 'T':
		tcpaddr = estrdup(netmkaddr(EARGF(usage()), "tcp", "domain"));
		break;
	default:
		usage();
	}ARGEND
	
	if(argc)
		usage();
	if(serveudp && servetcp)
		checkaddress();

	rfork(RFNOTEG);

	/* start syslog before we fork */
	fmtinstall('F', fcallfmt);
	dninit();
	if(myipaddr(ipaddr, mntpt) < 0)
		sysfatal("can't read my ip address");

	syslog(0, logfile, "starting dns on %I", ipaddr);

	opendatabase();

	mountinit(service);

	now = time(0);
	srand(now*getpid());
	db2cache(1);

	if(serveudp)
		proccreate(dnudpserver, nil, STACK);
	if(servetcp)
		proccreate(dntcpserver, nil, STACK);
	if(sendnotifies)
		proccreate(notifyproc, nil, STACK);

	io();
}