xref: /original-bsd/usr.sbin/sendmail/src/daemon.c (revision 6d0f5438)
1 /*
2  * Copyright (c) 1983 Eric P. Allman
3  * Copyright (c) 1988, 1993
4  *	The Regents of the University of California.  All rights reserved.
5  *
6  * %sccs.include.redist.c%
7  */
8 
9 #include <errno.h>
10 #include "sendmail.h"
11 
12 #ifndef lint
13 #ifdef DAEMON
14 static char sccsid[] = "@(#)daemon.c	8.37 (Berkeley) 02/08/94 (with daemon mode)";
15 #else
16 static char sccsid[] = "@(#)daemon.c	8.37 (Berkeley) 02/08/94 (without daemon mode)";
17 #endif
18 #endif /* not lint */
19 
20 #ifdef DAEMON
21 
22 # include <netdb.h>
23 # include <arpa/inet.h>
24 
25 #ifdef NAMED_BIND
26 # include <arpa/nameser.h>
27 # include <resolv.h>
28 #endif
29 
30 /*
31 **  DAEMON.C -- routines to use when running as a daemon.
32 **
33 **	This entire file is highly dependent on the 4.2 BSD
34 **	interprocess communication primitives.  No attempt has
35 **	been made to make this file portable to Version 7,
36 **	Version 6, MPX files, etc.  If you should try such a
37 **	thing yourself, I recommend chucking the entire file
38 **	and starting from scratch.  Basic semantics are:
39 **
40 **	getrequests()
41 **		Opens a port and initiates a connection.
42 **		Returns in a child.  Must set InChannel and
43 **		OutChannel appropriately.
44 **	clrdaemon()
45 **		Close any open files associated with getting
46 **		the connection; this is used when running the queue,
47 **		etc., to avoid having extra file descriptors during
48 **		the queue run and to avoid confusing the network
49 **		code (if it cares).
50 **	makeconnection(host, port, outfile, infile, usesecureport)
51 **		Make a connection to the named host on the given
52 **		port.  Set *outfile and *infile to the files
53 **		appropriate for communication.  Returns zero on
54 **		success, else an exit status describing the
55 **		error.
56 **	host_map_lookup(map, hbuf, avp, pstat)
57 **		Convert the entry in hbuf into a canonical form.
58 */
59 /*
60 **  GETREQUESTS -- open mail IPC port and get requests.
61 **
62 **	Parameters:
63 **		none.
64 **
65 **	Returns:
66 **		none.
67 **
68 **	Side Effects:
69 **		Waits until some interesting activity occurs.  When
70 **		it does, a child is created to process it, and the
71 **		parent waits for completion.  Return from this
72 **		routine is always in the child.  The file pointers
73 **		"InChannel" and "OutChannel" should be set to point
74 **		to the communication channel.
75 */
76 
77 int		DaemonSocket	= -1;		/* fd describing socket */
78 SOCKADDR	DaemonAddr;			/* socket for incoming */
79 int		ListenQueueSize = 10;		/* size of listen queue */
80 int		TcpRcvBufferSize = 0;		/* size of TCP receive buffer */
81 int		TcpSndBufferSize = 0;		/* size of TCP send buffer */
82 
83 getrequests()
84 {
85 	int t;
86 	int on = 1;
87 	bool refusingconnections = TRUE;
88 	FILE *pidf;
89 	int socksize;
90 	extern void reapchild();
91 
92 	/*
93 	**  Set up the address for the mailer.
94 	*/
95 
96 	if (DaemonAddr.sin.sin_family == 0)
97 		DaemonAddr.sin.sin_family = AF_INET;
98 	if (DaemonAddr.sin.sin_addr.s_addr == 0)
99 		DaemonAddr.sin.sin_addr.s_addr = INADDR_ANY;
100 	if (DaemonAddr.sin.sin_port == 0)
101 	{
102 		register struct servent *sp;
103 
104 		sp = getservbyname("smtp", "tcp");
105 		if (sp == NULL)
106 		{
107 			syserr("554 service \"smtp\" unknown");
108 			DaemonAddr.sin.sin_port = htons(25);
109 		}
110 		else
111 			DaemonAddr.sin.sin_port = sp->s_port;
112 	}
113 
114 	/*
115 	**  Try to actually open the connection.
116 	*/
117 
118 	if (tTd(15, 1))
119 		printf("getrequests: port 0x%x\n", DaemonAddr.sin.sin_port);
120 
121 	/* get a socket for the SMTP connection */
122 	DaemonSocket = socket(DaemonAddr.sa.sa_family, SOCK_STREAM, 0);
123 	if (DaemonSocket < 0)
124 	{
125 		/* probably another daemon already */
126 		syserr("getrequests: can't create socket");
127 	  severe:
128 # ifdef LOG
129 		if (LogLevel > 0)
130 			syslog(LOG_ALERT, "problem creating SMTP socket");
131 # endif /* LOG */
132 		finis();
133 	}
134 
135 	/* turn on network debugging? */
136 	if (tTd(15, 101))
137 		(void) setsockopt(DaemonSocket, SOL_SOCKET, SO_DEBUG, (char *)&on, sizeof on);
138 
139 	(void) setsockopt(DaemonSocket, SOL_SOCKET, SO_REUSEADDR, (char *)&on, sizeof on);
140 	(void) setsockopt(DaemonSocket, SOL_SOCKET, SO_KEEPALIVE, (char *)&on, sizeof on);
141 
142 #ifdef SO_RCVBUF
143 	if (TcpRcvBufferSize > 0)
144 	{
145 		if (setsockopt(DaemonSocket, SOL_SOCKET, SO_RCVBUF,
146 			       (char *) &TcpRcvBufferSize,
147 			       sizeof(TcpRcvBufferSize)) < 0)
148 			syserr("getrequests: setsockopt(SO_RCVBUF)");
149 	}
150 #endif
151 
152 	switch (DaemonAddr.sa.sa_family)
153 	{
154 # ifdef NETINET
155 	  case AF_INET:
156 		socksize = sizeof DaemonAddr.sin;
157 		break;
158 # endif
159 
160 # ifdef NETISO
161 	  case AF_ISO:
162 		socksize = sizeof DaemonAddr.siso;
163 		break;
164 # endif
165 
166 	  default:
167 		socksize = sizeof DaemonAddr;
168 		break;
169 	}
170 
171 	if (bind(DaemonSocket, &DaemonAddr.sa, socksize) < 0)
172 	{
173 		syserr("getrequests: cannot bind");
174 		(void) close(DaemonSocket);
175 		goto severe;
176 	}
177 
178 	(void) setsignal(SIGCHLD, reapchild);
179 
180 	/* write the pid to the log file for posterity */
181 	pidf = fopen(PidFile, "w");
182 	if (pidf != NULL)
183 	{
184 		extern char *CommandLineArgs;
185 
186 		/* write the process id on line 1 */
187 		fprintf(pidf, "%d\n", getpid());
188 
189 		/* line 2 contains all command line flags */
190 		fprintf(pidf, "%s\n", CommandLineArgs);
191 
192 		/* flush and close */
193 		fclose(pidf);
194 	}
195 
196 
197 	if (tTd(15, 1))
198 		printf("getrequests: %d\n", DaemonSocket);
199 
200 	for (;;)
201 	{
202 		register int pid;
203 		auto int lotherend;
204 		extern bool refuseconnections();
205 
206 		/* see if we are rejecting connections */
207 		CurrentLA = getla();
208 		if (refuseconnections())
209 		{
210 			if (!refusingconnections)
211 			{
212 				/* don't queue so peer will fail quickly */
213 				(void) listen(DaemonSocket, 0);
214 				refusingconnections = TRUE;
215 			}
216 			setproctitle("rejecting connections: load average: %d",
217 				CurrentLA);
218 			sleep(5);
219 			continue;
220 		}
221 
222 		if (refusingconnections)
223 		{
224 			/* start listening again */
225 			if (listen(DaemonSocket, ListenQueueSize) < 0)
226 			{
227 				syserr("getrequests: cannot listen");
228 				(void) close(DaemonSocket);
229 				goto severe;
230 			}
231 			setproctitle("accepting connections");
232 			refusingconnections = FALSE;
233 		}
234 
235 		/* wait for a connection */
236 		do
237 		{
238 			errno = 0;
239 			lotherend = socksize;
240 			t = accept(DaemonSocket,
241 			    (struct sockaddr *)&RealHostAddr, &lotherend);
242 		} while (t < 0 && errno == EINTR);
243 		if (t < 0)
244 		{
245 			syserr("getrequests: accept");
246 			sleep(5);
247 			continue;
248 		}
249 
250 		/*
251 		**  Create a subprocess to process the mail.
252 		*/
253 
254 		if (tTd(15, 2))
255 			printf("getrequests: forking (fd = %d)\n", t);
256 
257 		pid = fork();
258 		if (pid < 0)
259 		{
260 			syserr("daemon: cannot fork");
261 			sleep(10);
262 			(void) close(t);
263 			continue;
264 		}
265 
266 		if (pid == 0)
267 		{
268 			char *p;
269 			extern char *hostnamebyanyaddr();
270 
271 			/*
272 			**  CHILD -- return to caller.
273 			**	Collect verified idea of sending host.
274 			**	Verify calling user id if possible here.
275 			*/
276 
277 			(void) setsignal(SIGCHLD, SIG_DFL);
278 			DisConnected = FALSE;
279 
280 			setproctitle("startup with %s",
281 				anynet_ntoa(&RealHostAddr));
282 
283 			/* determine host name */
284 			p = hostnamebyanyaddr(&RealHostAddr);
285 			RealHostName = newstr(p);
286 			setproctitle("startup with %s", p);
287 
288 #ifdef LOG
289 			if (LogLevel > 11)
290 			{
291 				/* log connection information */
292 				syslog(LOG_INFO, "connect from %s (%s)",
293 					RealHostName, anynet_ntoa(&RealHostAddr));
294 			}
295 #endif
296 
297 			(void) close(DaemonSocket);
298 			if ((InChannel = fdopen(t, "r")) == NULL ||
299 			    (t = dup(t)) < 0 ||
300 			    (OutChannel = fdopen(t, "w")) == NULL)
301 			{
302 				syserr("cannot open SMTP server channel, fd=%d", t);
303 				exit(0);
304 			}
305 
306 			/* should we check for illegal connection here? XXX */
307 #ifdef XLA
308 			if (!xla_host_ok(RealHostName))
309 			{
310 				message("421 Too many SMTP sessions for this host");
311 				exit(0);
312 			}
313 #endif
314 
315 			if (tTd(15, 2))
316 				printf("getreq: returning\n");
317 			return;
318 		}
319 
320 		/* close the port so that others will hang (for a while) */
321 		(void) close(t);
322 	}
323 	/*NOTREACHED*/
324 }
325 /*
326 **  CLRDAEMON -- reset the daemon connection
327 **
328 **	Parameters:
329 **		none.
330 **
331 **	Returns:
332 **		none.
333 **
334 **	Side Effects:
335 **		releases any resources used by the passive daemon.
336 */
337 
338 clrdaemon()
339 {
340 	if (DaemonSocket >= 0)
341 		(void) close(DaemonSocket);
342 	DaemonSocket = -1;
343 }
344 /*
345 **  SETDAEMONOPTIONS -- set options for running the daemon
346 **
347 **	Parameters:
348 **		p -- the options line.
349 **
350 **	Returns:
351 **		none.
352 */
353 
354 setdaemonoptions(p)
355 	register char *p;
356 {
357 	if (DaemonAddr.sa.sa_family == AF_UNSPEC)
358 		DaemonAddr.sa.sa_family = AF_INET;
359 
360 	while (p != NULL)
361 	{
362 		register char *f;
363 		register char *v;
364 
365 		while (isascii(*p) && isspace(*p))
366 			p++;
367 		if (*p == '\0')
368 			break;
369 		f = p;
370 		p = strchr(p, ',');
371 		if (p != NULL)
372 			*p++ = '\0';
373 		v = strchr(f, '=');
374 		if (v == NULL)
375 			continue;
376 		while (isascii(*++v) && isspace(*v))
377 			continue;
378 
379 		switch (*f)
380 		{
381 		  case 'F':		/* address family */
382 			if (isascii(*v) && isdigit(*v))
383 				DaemonAddr.sa.sa_family = atoi(v);
384 #ifdef NETINET
385 			else if (strcasecmp(v, "inet") == 0)
386 				DaemonAddr.sa.sa_family = AF_INET;
387 #endif
388 #ifdef NETISO
389 			else if (strcasecmp(v, "iso") == 0)
390 				DaemonAddr.sa.sa_family = AF_ISO;
391 #endif
392 #ifdef NETNS
393 			else if (strcasecmp(v, "ns") == 0)
394 				DaemonAddr.sa.sa_family = AF_NS;
395 #endif
396 #ifdef NETX25
397 			else if (strcasecmp(v, "x.25") == 0)
398 				DaemonAddr.sa.sa_family = AF_CCITT;
399 #endif
400 			else
401 				syserr("554 Unknown address family %s in Family=option", v);
402 			break;
403 
404 		  case 'A':		/* address */
405 			switch (DaemonAddr.sa.sa_family)
406 			{
407 #ifdef NETINET
408 			  case AF_INET:
409 				if (isascii(*v) && isdigit(*v))
410 					DaemonAddr.sin.sin_addr.s_addr = inet_network(v);
411 				else
412 				{
413 					register struct netent *np;
414 
415 					np = getnetbyname(v);
416 					if (np == NULL)
417 						syserr("554 network \"%s\" unknown", v);
418 					else
419 						DaemonAddr.sin.sin_addr.s_addr = np->n_net;
420 				}
421 				break;
422 #endif
423 
424 			  default:
425 				syserr("554 Address= option unsupported for family %d",
426 					DaemonAddr.sa.sa_family);
427 				break;
428 			}
429 			break;
430 
431 		  case 'P':		/* port */
432 			switch (DaemonAddr.sa.sa_family)
433 			{
434 				short port;
435 
436 #ifdef NETINET
437 			  case AF_INET:
438 				if (isascii(*v) && isdigit(*v))
439 					DaemonAddr.sin.sin_port = htons(atoi(v));
440 				else
441 				{
442 					register struct servent *sp;
443 
444 					sp = getservbyname(v, "tcp");
445 					if (sp == NULL)
446 						syserr("554 service \"%s\" unknown", v);
447 					else
448 						DaemonAddr.sin.sin_port = sp->s_port;
449 				}
450 				break;
451 #endif
452 
453 #ifdef NETISO
454 			  case AF_ISO:
455 				/* assume two byte transport selector */
456 				if (isascii(*v) && isdigit(*v))
457 					port = htons(atoi(v));
458 				else
459 				{
460 					register struct servent *sp;
461 
462 					sp = getservbyname(v, "tcp");
463 					if (sp == NULL)
464 						syserr("554 service \"%s\" unknown", v);
465 					else
466 						port = sp->s_port;
467 				}
468 				bcopy((char *) &port, TSEL(&DaemonAddr.siso), 2);
469 				break;
470 #endif
471 
472 			  default:
473 				syserr("554 Port= option unsupported for family %d",
474 					DaemonAddr.sa.sa_family);
475 				break;
476 			}
477 			break;
478 
479 		  case 'L':		/* listen queue size */
480 			ListenQueueSize = atoi(v);
481 			break;
482 
483 		  case 'S':		/* send buffer size */
484 			TcpSndBufferSize = atoi(v);
485 			break;
486 
487 		  case 'R':		/* receive buffer size */
488 			TcpRcvBufferSize = atoi(v);
489 			break;
490 		}
491 	}
492 }
493 /*
494 **  MAKECONNECTION -- make a connection to an SMTP socket on another machine.
495 **
496 **	Parameters:
497 **		host -- the name of the host.
498 **		port -- the port number to connect to.
499 **		mci -- a pointer to the mail connection information
500 **			structure to be filled in.
501 **		usesecureport -- if set, use a low numbered (reserved)
502 **			port to provide some rudimentary authentication.
503 **
504 **	Returns:
505 **		An exit code telling whether the connection could be
506 **			made and if not why not.
507 **
508 **	Side Effects:
509 **		none.
510 */
511 
512 SOCKADDR	CurHostAddr;		/* address of current host */
513 
514 int
515 makeconnection(host, port, mci, usesecureport)
516 	char *host;
517 	u_short port;
518 	register MCI *mci;
519 	bool usesecureport;
520 {
521 	register int i, s;
522 	register struct hostent *hp = (struct hostent *)NULL;
523 	SOCKADDR addr;
524 	int sav_errno;
525 	int addrlen;
526 #ifdef NAMED_BIND
527 	extern int h_errno;
528 #endif
529 
530 	/*
531 	**  Set up the address for the mailer.
532 	**	Accept "[a.b.c.d]" syntax for host name.
533 	*/
534 
535 #ifdef NAMED_BIND
536 	h_errno = 0;
537 #endif
538 	errno = 0;
539 	bzero(&CurHostAddr, sizeof CurHostAddr);
540 	SmtpPhase = mci->mci_phase = "initial connection";
541 	CurHostName = host;
542 
543 	if (host[0] == '[')
544 	{
545 		long hid;
546 		register char *p = strchr(host, ']');
547 
548 		if (p != NULL)
549 		{
550 			*p = '\0';
551 #ifdef NETINET
552 			hid = inet_addr(&host[1]);
553 			if (hid == -1)
554 #endif
555 			{
556 				/* try it as a host name (avoid MX lookup) */
557 				hp = gethostbyname(&host[1]);
558 				*p = ']';
559 				goto gothostent;
560 			}
561 			*p = ']';
562 		}
563 		if (p == NULL)
564 		{
565 			usrerr("553 Invalid numeric domain spec \"%s\"", host);
566 			return (EX_NOHOST);
567 		}
568 #ifdef NETINET
569 		addr.sin.sin_family = AF_INET;		/*XXX*/
570 		addr.sin.sin_addr.s_addr = hid;
571 #endif
572 	}
573 	else
574 	{
575 		hp = gethostbyname(host);
576 gothostent:
577 		if (hp == NULL)
578 		{
579 #ifdef NAMED_BIND
580 			if (errno == ETIMEDOUT || h_errno == TRY_AGAIN)
581 				return (EX_TEMPFAIL);
582 
583 			/* if name server is specified, assume temp fail */
584 			if (errno == ECONNREFUSED && UseNameServer)
585 				return (EX_TEMPFAIL);
586 #endif
587 			return (EX_NOHOST);
588 		}
589 		addr.sa.sa_family = hp->h_addrtype;
590 		switch (hp->h_addrtype)
591 		{
592 #ifdef NETINET
593 		  case AF_INET:
594 			bcopy(hp->h_addr,
595 				&addr.sin.sin_addr,
596 				sizeof addr.sin.sin_addr);
597 			break;
598 #endif
599 
600 		  default:
601 			bcopy(hp->h_addr,
602 				addr.sa.sa_data,
603 				hp->h_length);
604 			break;
605 		}
606 		i = 1;
607 	}
608 
609 	/*
610 	**  Determine the port number.
611 	*/
612 
613 	if (port != 0)
614 		port = htons(port);
615 	else
616 	{
617 		register struct servent *sp = getservbyname("smtp", "tcp");
618 
619 		if (sp == NULL)
620 		{
621 			syserr("554 makeconnection: service \"smtp\" unknown");
622 			port = htons(25);
623 		}
624 		else
625 			port = sp->s_port;
626 	}
627 
628 	switch (addr.sa.sa_family)
629 	{
630 #ifdef NETINET
631 	  case AF_INET:
632 		addr.sin.sin_port = port;
633 		addrlen = sizeof (struct sockaddr_in);
634 		break;
635 #endif
636 
637 #ifdef NETISO
638 	  case AF_ISO:
639 		/* assume two byte transport selector */
640 		bcopy((char *) &port, TSEL((struct sockaddr_iso *) &addr), 2);
641 		addrlen = sizeof (struct sockaddr_iso);
642 		break;
643 #endif
644 
645 	  default:
646 		syserr("Can't connect to address family %d", addr.sa.sa_family);
647 		return (EX_NOHOST);
648 	}
649 
650 	/*
651 	**  Try to actually open the connection.
652 	*/
653 
654 #ifdef XLA
655 	/* if too many connections, don't bother trying */
656 	if (!xla_noqueue_ok(host))
657 		return EX_TEMPFAIL;
658 #endif
659 
660 	for (;;)
661 	{
662 		if (tTd(16, 1))
663 			printf("makeconnection (%s [%s])\n",
664 				host, anynet_ntoa(&addr));
665 
666 		/* save for logging */
667 		CurHostAddr = addr;
668 
669 		if (usesecureport)
670 		{
671 			int rport = IPPORT_RESERVED - 1;
672 
673 			s = rresvport(&rport);
674 		}
675 		else
676 		{
677 			s = socket(AF_INET, SOCK_STREAM, 0);
678 		}
679 		if (s < 0)
680 		{
681 			sav_errno = errno;
682 			syserr("makeconnection: no socket");
683 			goto failure;
684 		}
685 
686 #ifdef SO_SNDBUF
687 		if (TcpSndBufferSize > 0)
688 		{
689 			if (setsockopt(s, SOL_SOCKET, SO_SNDBUF,
690 				       (char *) &TcpSndBufferSize,
691 				       sizeof(TcpSndBufferSize)) < 0)
692 				syserr("makeconnection: setsockopt(SO_SNDBUF)");
693 		}
694 #endif
695 
696 		if (tTd(16, 1))
697 			printf("makeconnection: fd=%d\n", s);
698 
699 		/* turn on network debugging? */
700 		if (tTd(16, 101))
701 		{
702 			int on = 1;
703 			(void) setsockopt(DaemonSocket, SOL_SOCKET, SO_DEBUG,
704 					  (char *)&on, sizeof on);
705 		}
706 		if (CurEnv->e_xfp != NULL)
707 			(void) fflush(CurEnv->e_xfp);		/* for debugging */
708 		errno = 0;					/* for debugging */
709 		if (connect(s, (struct sockaddr *) &addr, addrlen) >= 0)
710 			break;
711 
712 		/* couldn't connect.... figure out why */
713 		sav_errno = errno;
714 		(void) close(s);
715 		if (hp && hp->h_addr_list[i])
716 		{
717 			if (tTd(16, 1))
718 				printf("Connect failed (%s); trying new address....\n",
719 					errstring(sav_errno));
720 			switch (addr.sa.sa_family)
721 			{
722 #ifdef NETINET
723 			  case AF_INET:
724 				bcopy(hp->h_addr_list[i++],
725 				      &addr.sin.sin_addr,
726 				      sizeof addr.sin.sin_addr);
727 				break;
728 #endif
729 
730 			  default:
731 				bcopy(hp->h_addr_list[i++],
732 					addr.sa.sa_data,
733 					hp->h_length);
734 				break;
735 			}
736 			continue;
737 		}
738 
739 		/* failure, decide if temporary or not */
740 	failure:
741 #ifdef XLA
742 		xla_host_end(host);
743 #endif
744 		if (transienterror(sav_errno))
745 			return EX_TEMPFAIL;
746 		else
747 		{
748 			message("%s", errstring(sav_errno));
749 			return (EX_UNAVAILABLE);
750 		}
751 	}
752 
753 	/* connection ok, put it into canonical form */
754 	if ((mci->mci_out = fdopen(s, "w")) == NULL ||
755 	    (s = dup(s)) < 0 ||
756 	    (mci->mci_in = fdopen(s, "r")) == NULL)
757 	{
758 		syserr("cannot open SMTP client channel, fd=%d", s);
759 		return EX_TEMPFAIL;
760 	}
761 
762 	return (EX_OK);
763 }
764 /*
765 **  MYHOSTNAME -- return the name of this host.
766 **
767 **	Parameters:
768 **		hostbuf -- a place to return the name of this host.
769 **		size -- the size of hostbuf.
770 **
771 **	Returns:
772 **		A list of aliases for this host.
773 **
774 **	Side Effects:
775 **		Adds numeric codes to $=w.
776 */
777 
778 char **
779 myhostname(hostbuf, size)
780 	char hostbuf[];
781 	int size;
782 {
783 	register struct hostent *hp;
784 	extern struct hostent *gethostbyname();
785 
786 	if (gethostname(hostbuf, size) < 0)
787 	{
788 		(void) strcpy(hostbuf, "localhost");
789 	}
790 	hp = gethostbyname(hostbuf);
791 	if (hp != NULL)
792 	{
793 		(void) strncpy(hostbuf, hp->h_name, size - 1);
794 		hostbuf[size - 1] = '\0';
795 
796 		if (hp->h_addrtype == AF_INET && hp->h_length == 4)
797 		{
798 			register int i;
799 
800 			for (i = 0; hp->h_addr_list[i] != NULL; i++)
801 			{
802 				char ipbuf[100];
803 
804 				sprintf(ipbuf, "[%s]",
805 					inet_ntoa(*((struct in_addr *) hp->h_addr_list[i])));
806 				setclass('w', ipbuf);
807 			}
808 		}
809 
810 		return (hp->h_aliases);
811 	}
812 	else
813 		return (NULL);
814 }
815 /*
816 **  GETAUTHINFO -- get the real host name asociated with a file descriptor
817 **
818 **	Uses RFC1413 protocol to try to get info from the other end.
819 **
820 **	Parameters:
821 **		fd -- the descriptor
822 **
823 **	Returns:
824 **		The user@host information associated with this descriptor.
825 */
826 
827 #if IDENTPROTO
828 
829 static jmp_buf	CtxAuthTimeout;
830 
831 static
832 authtimeout()
833 {
834 	longjmp(CtxAuthTimeout, 1);
835 }
836 
837 #endif
838 
839 char *
840 getauthinfo(fd)
841 	int fd;
842 {
843 	SOCKADDR fa;
844 	int falen;
845 	register char *p;
846 #if IDENTPROTO
847 	SOCKADDR la;
848 	int lalen;
849 	register struct servent *sp;
850 	int s;
851 	int i;
852 	EVENT *ev;
853 #endif
854 	static char hbuf[MAXNAME * 2 + 2];
855 	extern char *hostnamebyanyaddr();
856 	extern char RealUserName[];			/* main.c */
857 
858 	falen = sizeof fa;
859 	if (getpeername(fd, &fa.sa, &falen) < 0 || falen <= 0 ||
860 	    fa.sa.sa_family == 0)
861 	{
862 		(void) sprintf(hbuf, "%s@localhost", RealUserName);
863 		if (tTd(9, 1))
864 			printf("getauthinfo: %s\n", hbuf);
865 		return hbuf;
866 	}
867 
868 #if IDENTPROTO
869 	if (TimeOuts.to_ident == 0)
870 		goto noident;
871 
872 	lalen = sizeof la;
873 	if (fa.sa.sa_family != AF_INET ||
874 	    getsockname(fd, &la.sa, &lalen) < 0 || lalen <= 0 ||
875 	    la.sa.sa_family != AF_INET)
876 	{
877 		/* no ident info */
878 		goto noident;
879 	}
880 
881 	/* create ident query */
882 	(void) sprintf(hbuf, "%d,%d\r\n",
883 		ntohs(fa.sin.sin_port), ntohs(la.sin.sin_port));
884 
885 	/* create local address */
886 	la.sin.sin_port = 0;
887 
888 	/* create foreign address */
889 	sp = getservbyname("auth", "tcp");
890 	if (sp != NULL)
891 		fa.sin.sin_port = sp->s_port;
892 	else
893 		fa.sin.sin_port = htons(113);
894 
895 	s = -1;
896 	if (setjmp(CtxAuthTimeout) != 0)
897 	{
898 		if (s >= 0)
899 			(void) close(s);
900 		goto noident;
901 	}
902 
903 	/* put a timeout around the whole thing */
904 	ev = setevent(TimeOuts.to_ident, authtimeout, 0);
905 
906 	/* connect to foreign IDENT server using same address as SMTP socket */
907 	s = socket(AF_INET, SOCK_STREAM, 0);
908 	if (s < 0)
909 	{
910 		clrevent(ev);
911 		goto noident;
912 	}
913 	if (bind(s, &la.sa, sizeof la.sin) < 0 ||
914 	    connect(s, &fa.sa, sizeof fa.sin) < 0)
915 	{
916 		goto closeident;
917 	}
918 
919 	if (tTd(9, 10))
920 		printf("getauthinfo: sent %s", hbuf);
921 
922 	/* send query */
923 	if (write(s, hbuf, strlen(hbuf)) < 0)
924 		goto closeident;
925 
926 	/* get result */
927 	i = read(s, hbuf, sizeof hbuf);
928 	(void) close(s);
929 	clrevent(ev);
930 	if (i <= 0)
931 		goto noident;
932 	if (hbuf[--i] == '\n' && hbuf[--i] == '\r')
933 		i--;
934 	hbuf[++i] = '\0';
935 
936 	if (tTd(9, 3))
937 		printf("getauthinfo:  got %s\n", hbuf);
938 
939 	/* parse result */
940 	p = strchr(hbuf, ':');
941 	if (p == NULL)
942 	{
943 		/* malformed response */
944 		goto noident;
945 	}
946 	while (isascii(*++p) && isspace(*p))
947 		continue;
948 	if (strncasecmp(p, "userid", 6) != 0)
949 	{
950 		/* presumably an error string */
951 		goto noident;
952 	}
953 	p += 6;
954 	while (isascii(*p) && isspace(*p))
955 		p++;
956 	if (*p++ != ':')
957 	{
958 		/* either useridxx or malformed response */
959 		goto noident;
960 	}
961 
962 	/* p now points to the OSTYPE field */
963 	p = strchr(p, ':');
964 	if (p == NULL)
965 	{
966 		/* malformed response */
967 		goto noident;
968 	}
969 
970 	/* 1413 says don't do this -- but it's broken otherwise */
971 	while (isascii(*++p) && isspace(*p))
972 		continue;
973 
974 	/* p now points to the authenticated name */
975 	(void) sprintf(hbuf, "%s@%s",
976 		p, RealHostName == NULL ? "localhost" : RealHostName);
977 	goto finish;
978 
979 closeident:
980 	(void) close(s);
981 	clrevent(ev);
982 
983 #endif /* IDENTPROTO */
984 
985 noident:
986 	if (RealHostName == NULL)
987 	{
988 		if (tTd(9, 1))
989 			printf("getauthinfo: NULL\n");
990 		return NULL;
991 	}
992 	(void) strcpy(hbuf, RealHostName);
993 
994 finish:
995 	if (RealHostName != NULL && RealHostName[0] != '[')
996 	{
997 		p = &hbuf[strlen(hbuf)];
998 		(void) sprintf(p, " [%s]", anynet_ntoa(&RealHostAddr));
999 	}
1000 	if (tTd(9, 1))
1001 		printf("getauthinfo: %s\n", hbuf);
1002 	return hbuf;
1003 }
1004 /*
1005 **  HOST_MAP_LOOKUP -- turn a hostname into canonical form
1006 **
1007 **	Parameters:
1008 **		map -- a pointer to this map (unused).
1009 **		name -- the (presumably unqualified) hostname.
1010 **		av -- unused -- for compatibility with other mapping
1011 **			functions.
1012 **		statp -- an exit status (out parameter) -- set to
1013 **			EX_TEMPFAIL if the name server is unavailable.
1014 **
1015 **	Returns:
1016 **		The mapping, if found.
1017 **		NULL if no mapping found.
1018 **
1019 **	Side Effects:
1020 **		Looks up the host specified in hbuf.  If it is not
1021 **		the canonical name for that host, return the canonical
1022 **		name.
1023 */
1024 
1025 char *
1026 host_map_lookup(map, name, av, statp)
1027 	MAP *map;
1028 	char *name;
1029 	char **av;
1030 	int *statp;
1031 {
1032 	register struct hostent *hp;
1033 	u_long in_addr;
1034 	char *cp;
1035 	int i;
1036 	register STAB *s;
1037 	char hbuf[MAXNAME];
1038 	extern struct hostent *gethostbyaddr();
1039 #ifdef NAMED_BIND
1040 	extern int h_errno;
1041 #endif
1042 
1043 	/*
1044 	**  See if we have already looked up this name.  If so, just
1045 	**  return it.
1046 	*/
1047 
1048 	s = stab(name, ST_NAMECANON, ST_ENTER);
1049 	if (bitset(NCF_VALID, s->s_namecanon.nc_flags))
1050 	{
1051 		if (tTd(9, 1))
1052 			printf("host_map_lookup(%s) => CACHE %s\n",
1053 				name, s->s_namecanon.nc_cname);
1054 		errno = s->s_namecanon.nc_errno;
1055 #ifdef NAMED_BIND
1056 		h_errno = s->s_namecanon.nc_herrno;
1057 #endif
1058 		*statp = s->s_namecanon.nc_stat;
1059 		if (CurEnv->e_message == NULL && *statp == EX_TEMPFAIL)
1060 		{
1061 			sprintf(hbuf, "%s: Name server timeout",
1062 				shortenstring(name, 33));
1063 			CurEnv->e_message = newstr(hbuf);
1064 		}
1065 		return s->s_namecanon.nc_cname;
1066 	}
1067 
1068 	/*
1069 	**  If first character is a bracket, then it is an address
1070 	**  lookup.  Address is copied into a temporary buffer to
1071 	**  strip the brackets and to preserve name if address is
1072 	**  unknown.
1073 	*/
1074 
1075 	if (*name != '[')
1076 	{
1077 		extern bool getcanonname();
1078 
1079 		if (tTd(9, 1))
1080 			printf("host_map_lookup(%s) => ", name);
1081 		s->s_namecanon.nc_flags |= NCF_VALID;		/* will be soon */
1082 		(void) strcpy(hbuf, name);
1083 		if (getcanonname(hbuf, sizeof hbuf - 1, TRUE))
1084 		{
1085 			if (tTd(9, 1))
1086 				printf("%s\n", hbuf);
1087 			cp = map_rewrite(map, hbuf, strlen(hbuf), av);
1088 			s->s_namecanon.nc_cname = newstr(cp);
1089 			return cp;
1090 		}
1091 		else
1092 		{
1093 			register struct hostent *hp;
1094 
1095 			s->s_namecanon.nc_errno = errno;
1096 #ifdef NAMED_BIND
1097 			s->s_namecanon.nc_herrno = h_errno;
1098 			if (tTd(9, 1))
1099 				printf("FAIL (%d)\n", h_errno);
1100 			switch (h_errno)
1101 			{
1102 			  case TRY_AGAIN:
1103 				if (UseNameServer)
1104 				{
1105 					sprintf(hbuf, "%s: Name server timeout",
1106 						shortenstring(name, 33));
1107 					message("%s", hbuf);
1108 					if (CurEnv->e_message == NULL)
1109 						CurEnv->e_message = newstr(hbuf);
1110 				}
1111 				*statp = EX_TEMPFAIL;
1112 				break;
1113 
1114 			  case HOST_NOT_FOUND:
1115 				*statp = EX_NOHOST;
1116 				break;
1117 
1118 			  case NO_RECOVERY:
1119 				*statp = EX_SOFTWARE;
1120 				break;
1121 
1122 			  default:
1123 				*statp = EX_UNAVAILABLE;
1124 				break;
1125 			}
1126 #else
1127 			if (tTd(9, 1))
1128 				printf("FAIL\n");
1129 			*statp = EX_NOHOST;
1130 #endif
1131 			s->s_namecanon.nc_stat = *statp;
1132 			if (*statp != EX_TEMPFAIL || UseNameServer)
1133 				return NULL;
1134 
1135 			/*
1136 			**  Try to look it up in /etc/hosts
1137 			*/
1138 
1139 			hp = gethostbyname(name);
1140 			if (hp == NULL)
1141 			{
1142 				/* no dice there either */
1143 				s->s_namecanon.nc_stat = *statp = EX_NOHOST;
1144 				return NULL;
1145 			}
1146 
1147 			s->s_namecanon.nc_stat = *statp = EX_OK;
1148 			cp = map_rewrite(map, hp->h_name, strlen(hp->h_name), av);
1149 			s->s_namecanon.nc_cname = newstr(cp);
1150 			return cp;
1151 		}
1152 	}
1153 	if ((cp = strchr(name, ']')) == NULL)
1154 		return (NULL);
1155 	*cp = '\0';
1156 	in_addr = inet_addr(&name[1]);
1157 
1158 	/* nope -- ask the name server */
1159 	hp = gethostbyaddr((char *)&in_addr, sizeof(struct in_addr), AF_INET);
1160 	s->s_namecanon.nc_errno = errno;
1161 #ifdef NAMED_BIND
1162 	s->s_namecanon.nc_herrno = h_errno;
1163 #endif
1164 	s->s_namecanon.nc_flags |= NCF_VALID;		/* will be soon */
1165 	if (hp == NULL)
1166 	{
1167 		s->s_namecanon.nc_stat = *statp = EX_NOHOST;
1168 		return (NULL);
1169 	}
1170 
1171 	/* found a match -- copy out */
1172 	cp = map_rewrite(map, hp->h_name, strlen(hp->h_name), av);
1173 	s->s_namecanon.nc_stat = *statp = EX_OK;
1174 	s->s_namecanon.nc_cname = newstr(cp);
1175 	return cp;
1176 }
1177 /*
1178 **  ANYNET_NTOA -- convert a network address to printable form.
1179 **
1180 **	Parameters:
1181 **		sap -- a pointer to a sockaddr structure.
1182 **
1183 **	Returns:
1184 **		A printable version of that sockaddr.
1185 */
1186 
1187 char *
1188 anynet_ntoa(sap)
1189 	register SOCKADDR *sap;
1190 {
1191 	register char *bp;
1192 	register char *ap;
1193 	int l;
1194 	static char buf[100];
1195 
1196 	/* check for null/zero family */
1197 	if (sap == NULL)
1198 		return "NULLADDR";
1199 	if (sap->sa.sa_family == 0)
1200 		return "0";
1201 
1202 	switch (sap->sa.sa_family)
1203 	{
1204 #ifdef MAYBENEXTRELEASE		/*** UNTESTED *** UNTESTED *** UNTESTED ***/
1205 #ifdef NETUNIX
1206 	  case AF_UNIX:
1207 	  	if (sap->sunix.sun_path[0] != '\0')
1208 	  		sprintf(buf, "[UNIX: %.64s]", sap->sunix.sun_path);
1209 	  	else
1210 	  		sprintf(buf, "[UNIX: localhost]");
1211 		return buf;
1212 #endif
1213 #endif
1214 
1215 #ifdef NETINET
1216 	  case AF_INET:
1217 		return inet_ntoa(((struct sockaddr_in *) sap)->sin_addr);
1218 #endif
1219 
1220 	  default:
1221 	  	/* this case is only to ensure syntactic correctness */
1222 	  	break;
1223 	}
1224 
1225 	/* unknown family -- just dump bytes */
1226 	(void) sprintf(buf, "Family %d: ", sap->sa.sa_family);
1227 	bp = &buf[strlen(buf)];
1228 	ap = sap->sa.sa_data;
1229 	for (l = sizeof sap->sa.sa_data; --l >= 0; )
1230 	{
1231 		(void) sprintf(bp, "%02x:", *ap++ & 0377);
1232 		bp += 3;
1233 	}
1234 	*--bp = '\0';
1235 	return buf;
1236 }
1237 /*
1238 **  HOSTNAMEBYANYADDR -- return name of host based on address
1239 **
1240 **	Parameters:
1241 **		sap -- SOCKADDR pointer
1242 **
1243 **	Returns:
1244 **		text representation of host name.
1245 **
1246 **	Side Effects:
1247 **		none.
1248 */
1249 
1250 char *
1251 hostnamebyanyaddr(sap)
1252 	register SOCKADDR *sap;
1253 {
1254 	register struct hostent *hp;
1255 	int saveretry;
1256 
1257 #ifdef NAMED_BIND
1258 	/* shorten name server timeout to avoid higher level timeouts */
1259 	saveretry = _res.retry;
1260 	_res.retry = 3;
1261 #endif /* NAMED_BIND */
1262 
1263 	switch (sap->sa.sa_family)
1264 	{
1265 #ifdef NETINET
1266 	  case AF_INET:
1267 		hp = gethostbyaddr((char *) &sap->sin.sin_addr,
1268 			sizeof sap->sin.sin_addr,
1269 			AF_INET);
1270 		break;
1271 #endif
1272 
1273 #ifdef NETISO
1274 	  case AF_ISO:
1275 		hp = gethostbyaddr((char *) &sap->siso.siso_addr,
1276 			sizeof sap->siso.siso_addr,
1277 			AF_ISO);
1278 		break;
1279 #endif
1280 
1281 #ifdef MAYBENEXTRELEASE		/*** UNTESTED *** UNTESTED *** UNTESTED ***/
1282 	  case AF_UNIX:
1283 		hp = NULL;
1284 		break;
1285 #endif
1286 
1287 	  default:
1288 		hp = gethostbyaddr(sap->sa.sa_data,
1289 			   sizeof sap->sa.sa_data,
1290 			   sap->sa.sa_family);
1291 		break;
1292 	}
1293 
1294 #ifdef NAMED_BIND
1295 	_res.retry = saveretry;
1296 #endif /* NAMED_BIND */
1297 
1298 	if (hp != NULL)
1299 		return hp->h_name;
1300 	else
1301 	{
1302 		/* produce a dotted quad */
1303 		static char buf[512];
1304 
1305 		(void) sprintf(buf, "[%s]", anynet_ntoa(sap));
1306 		return buf;
1307 	}
1308 }
1309 
1310 # else /* DAEMON */
1311 /* code for systems without sophisticated networking */
1312 
1313 /*
1314 **  MYHOSTNAME -- stub version for case of no daemon code.
1315 **
1316 **	Can't convert to upper case here because might be a UUCP name.
1317 **
1318 **	Mark, you can change this to be anything you want......
1319 */
1320 
1321 char **
1322 myhostname(hostbuf, size)
1323 	char hostbuf[];
1324 	int size;
1325 {
1326 	register FILE *f;
1327 
1328 	hostbuf[0] = '\0';
1329 	f = fopen("/usr/include/whoami", "r");
1330 	if (f != NULL)
1331 	{
1332 		(void) fgets(hostbuf, size, f);
1333 		fixcrlf(hostbuf, TRUE);
1334 		(void) fclose(f);
1335 	}
1336 	return (NULL);
1337 }
1338 /*
1339 **  GETAUTHINFO -- get the real host name asociated with a file descriptor
1340 **
1341 **	Parameters:
1342 **		fd -- the descriptor
1343 **
1344 **	Returns:
1345 **		The host name associated with this descriptor, if it can
1346 **			be determined.
1347 **		NULL otherwise.
1348 **
1349 **	Side Effects:
1350 **		none
1351 */
1352 
1353 char *
1354 getauthinfo(fd)
1355 	int fd;
1356 {
1357 	return NULL;
1358 }
1359 /*
1360 **  MAPHOSTNAME -- turn a hostname into canonical form
1361 **
1362 **	Parameters:
1363 **		map -- a pointer to the database map.
1364 **		name -- a buffer containing a hostname.
1365 **		avp -- a pointer to a (cf file defined) argument vector.
1366 **		statp -- an exit status (out parameter).
1367 **
1368 **	Returns:
1369 **		mapped host name
1370 **		FALSE otherwise.
1371 **
1372 **	Side Effects:
1373 **		Looks up the host specified in name.  If it is not
1374 **		the canonical name for that host, replace it with
1375 **		the canonical name.  If the name is unknown, or it
1376 **		is already the canonical name, leave it unchanged.
1377 */
1378 
1379 /*ARGSUSED*/
1380 char *
1381 host_map_lookup(map, name, avp, statp)
1382 	MAP *map;
1383 	char *name;
1384 	char **avp;
1385 	char *statp;
1386 {
1387 	register struct hostent *hp;
1388 
1389 	hp = gethostbyname(name);
1390 	if (hp != NULL)
1391 		return hp->h_name;
1392 	*statp = EX_NOHOST;
1393 	return NULL;
1394 }
1395 
1396 #endif /* DAEMON */
1397