xref: /original-bsd/usr.sbin/sendmail/src/daemon.c (revision 9507f4d3)
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	8.35 (Berkeley) 02/06/94 (with daemon mode)";
15 #else
16 static char sccsid[] = "@(#)daemon.c	8.35 (Berkeley) 02/06/94 (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 			/* determine host name */
281 			p = hostnamebyanyaddr(&RealHostAddr);
282 			RealHostName = newstr(p);
283 
284 #ifdef LOG
285 			if (LogLevel > 11)
286 			{
287 				/* log connection information */
288 				syslog(LOG_INFO, "connect from %s (%s)",
289 					RealHostName, anynet_ntoa(&RealHostAddr));
290 			}
291 #endif
292 
293 			(void) close(DaemonSocket);
294 			if ((InChannel = fdopen(t, "r")) == NULL ||
295 			    (t = dup(t)) < 0 ||
296 			    (OutChannel = fdopen(t, "w")) == NULL)
297 			{
298 				syserr("cannot open SMTP server channel, fd=%d", t);
299 				exit(0);
300 			}
301 
302 			/* should we check for illegal connection here? XXX */
303 #ifdef XLA
304 			if (!xla_host_ok(RealHostName))
305 			{
306 				message("421 Too many SMTP sessions for this host");
307 				exit(0);
308 			}
309 #endif
310 
311 			if (tTd(15, 2))
312 				printf("getreq: returning\n");
313 			return;
314 		}
315 
316 		/* close the port so that others will hang (for a while) */
317 		(void) close(t);
318 	}
319 	/*NOTREACHED*/
320 }
321 /*
322 **  CLRDAEMON -- reset the daemon connection
323 **
324 **	Parameters:
325 **		none.
326 **
327 **	Returns:
328 **		none.
329 **
330 **	Side Effects:
331 **		releases any resources used by the passive daemon.
332 */
333 
334 clrdaemon()
335 {
336 	if (DaemonSocket >= 0)
337 		(void) close(DaemonSocket);
338 	DaemonSocket = -1;
339 }
340 /*
341 **  SETDAEMONOPTIONS -- set options for running the daemon
342 **
343 **	Parameters:
344 **		p -- the options line.
345 **
346 **	Returns:
347 **		none.
348 */
349 
350 setdaemonoptions(p)
351 	register char *p;
352 {
353 	if (DaemonAddr.sa.sa_family == AF_UNSPEC)
354 		DaemonAddr.sa.sa_family = AF_INET;
355 
356 	while (p != NULL)
357 	{
358 		register char *f;
359 		register char *v;
360 
361 		while (isascii(*p) && isspace(*p))
362 			p++;
363 		if (*p == '\0')
364 			break;
365 		f = p;
366 		p = strchr(p, ',');
367 		if (p != NULL)
368 			*p++ = '\0';
369 		v = strchr(f, '=');
370 		if (v == NULL)
371 			continue;
372 		while (isascii(*++v) && isspace(*v))
373 			continue;
374 
375 		switch (*f)
376 		{
377 		  case 'F':		/* address family */
378 			if (isascii(*v) && isdigit(*v))
379 				DaemonAddr.sa.sa_family = atoi(v);
380 #ifdef NETINET
381 			else if (strcasecmp(v, "inet") == 0)
382 				DaemonAddr.sa.sa_family = AF_INET;
383 #endif
384 #ifdef NETISO
385 			else if (strcasecmp(v, "iso") == 0)
386 				DaemonAddr.sa.sa_family = AF_ISO;
387 #endif
388 #ifdef NETNS
389 			else if (strcasecmp(v, "ns") == 0)
390 				DaemonAddr.sa.sa_family = AF_NS;
391 #endif
392 #ifdef NETX25
393 			else if (strcasecmp(v, "x.25") == 0)
394 				DaemonAddr.sa.sa_family = AF_CCITT;
395 #endif
396 			else
397 				syserr("554 Unknown address family %s in Family=option", v);
398 			break;
399 
400 		  case 'A':		/* address */
401 			switch (DaemonAddr.sa.sa_family)
402 			{
403 #ifdef NETINET
404 			  case AF_INET:
405 				if (isascii(*v) && isdigit(*v))
406 					DaemonAddr.sin.sin_addr.s_addr = inet_network(v);
407 				else
408 				{
409 					register struct netent *np;
410 
411 					np = getnetbyname(v);
412 					if (np == NULL)
413 						syserr("554 network \"%s\" unknown", v);
414 					else
415 						DaemonAddr.sin.sin_addr.s_addr = np->n_net;
416 				}
417 				break;
418 #endif
419 
420 			  default:
421 				syserr("554 Address= option unsupported for family %d",
422 					DaemonAddr.sa.sa_family);
423 				break;
424 			}
425 			break;
426 
427 		  case 'P':		/* port */
428 			switch (DaemonAddr.sa.sa_family)
429 			{
430 				short port;
431 
432 #ifdef NETINET
433 			  case AF_INET:
434 				if (isascii(*v) && isdigit(*v))
435 					DaemonAddr.sin.sin_port = htons(atoi(v));
436 				else
437 				{
438 					register struct servent *sp;
439 
440 					sp = getservbyname(v, "tcp");
441 					if (sp == NULL)
442 						syserr("554 service \"%s\" unknown", v);
443 					else
444 						DaemonAddr.sin.sin_port = sp->s_port;
445 				}
446 				break;
447 #endif
448 
449 #ifdef NETISO
450 			  case AF_ISO:
451 				/* assume two byte transport selector */
452 				if (isascii(*v) && isdigit(*v))
453 					port = htons(atoi(v));
454 				else
455 				{
456 					register struct servent *sp;
457 
458 					sp = getservbyname(v, "tcp");
459 					if (sp == NULL)
460 						syserr("554 service \"%s\" unknown", v);
461 					else
462 						port = sp->s_port;
463 				}
464 				bcopy((char *) &port, TSEL(&DaemonAddr.siso), 2);
465 				break;
466 #endif
467 
468 			  default:
469 				syserr("554 Port= option unsupported for family %d",
470 					DaemonAddr.sa.sa_family);
471 				break;
472 			}
473 			break;
474 
475 		  case 'L':		/* listen queue size */
476 			ListenQueueSize = atoi(v);
477 			break;
478 
479 		  case 'S':		/* send buffer size */
480 			TcpSndBufferSize = atoi(v);
481 			break;
482 
483 		  case 'R':		/* receive buffer size */
484 			TcpRcvBufferSize = atoi(v);
485 			break;
486 		}
487 	}
488 }
489 /*
490 **  MAKECONNECTION -- make a connection to an SMTP socket on another machine.
491 **
492 **	Parameters:
493 **		host -- the name of the host.
494 **		port -- the port number to connect to.
495 **		mci -- a pointer to the mail connection information
496 **			structure to be filled in.
497 **		usesecureport -- if set, use a low numbered (reserved)
498 **			port to provide some rudimentary authentication.
499 **
500 **	Returns:
501 **		An exit code telling whether the connection could be
502 **			made and if not why not.
503 **
504 **	Side Effects:
505 **		none.
506 */
507 
508 SOCKADDR	CurHostAddr;		/* address of current host */
509 
510 int
511 makeconnection(host, port, mci, usesecureport)
512 	char *host;
513 	u_short port;
514 	register MCI *mci;
515 	bool usesecureport;
516 {
517 	register int i, s;
518 	register struct hostent *hp = (struct hostent *)NULL;
519 	SOCKADDR addr;
520 	int sav_errno;
521 	int addrlen;
522 #ifdef NAMED_BIND
523 	extern int h_errno;
524 #endif
525 
526 	/*
527 	**  Set up the address for the mailer.
528 	**	Accept "[a.b.c.d]" syntax for host name.
529 	*/
530 
531 #ifdef NAMED_BIND
532 	h_errno = 0;
533 #endif
534 	errno = 0;
535 	bzero(&CurHostAddr, sizeof CurHostAddr);
536 	SmtpPhase = mci->mci_phase = "initial connection";
537 	CurHostName = host;
538 
539 	if (host[0] == '[')
540 	{
541 		long hid;
542 		register char *p = strchr(host, ']');
543 
544 		if (p != NULL)
545 		{
546 			*p = '\0';
547 #ifdef NETINET
548 			hid = inet_addr(&host[1]);
549 			if (hid == -1)
550 #endif
551 			{
552 				/* try it as a host name (avoid MX lookup) */
553 				hp = gethostbyname(&host[1]);
554 				*p = ']';
555 				goto gothostent;
556 			}
557 			*p = ']';
558 		}
559 		if (p == NULL)
560 		{
561 			usrerr("553 Invalid numeric domain spec \"%s\"", host);
562 			return (EX_NOHOST);
563 		}
564 #ifdef NETINET
565 		addr.sin.sin_family = AF_INET;		/*XXX*/
566 		addr.sin.sin_addr.s_addr = hid;
567 #endif
568 	}
569 	else
570 	{
571 		hp = gethostbyname(host);
572 gothostent:
573 		if (hp == NULL)
574 		{
575 #ifdef NAMED_BIND
576 			if (errno == ETIMEDOUT || h_errno == TRY_AGAIN)
577 				return (EX_TEMPFAIL);
578 
579 			/* if name server is specified, assume temp fail */
580 			if (errno == ECONNREFUSED && UseNameServer)
581 				return (EX_TEMPFAIL);
582 #endif
583 			return (EX_NOHOST);
584 		}
585 		addr.sa.sa_family = hp->h_addrtype;
586 		switch (hp->h_addrtype)
587 		{
588 #ifdef NETINET
589 		  case AF_INET:
590 			bcopy(hp->h_addr,
591 				&addr.sin.sin_addr,
592 				sizeof addr.sin.sin_addr);
593 			break;
594 #endif
595 
596 		  default:
597 			bcopy(hp->h_addr,
598 				addr.sa.sa_data,
599 				hp->h_length);
600 			break;
601 		}
602 		i = 1;
603 	}
604 
605 	/*
606 	**  Determine the port number.
607 	*/
608 
609 	if (port != 0)
610 		port = htons(port);
611 	else
612 	{
613 		register struct servent *sp = getservbyname("smtp", "tcp");
614 
615 		if (sp == NULL)
616 		{
617 			syserr("554 makeconnection: service \"smtp\" unknown");
618 			port = htons(25);
619 		}
620 		else
621 			port = sp->s_port;
622 	}
623 
624 	switch (addr.sa.sa_family)
625 	{
626 #ifdef NETINET
627 	  case AF_INET:
628 		addr.sin.sin_port = port;
629 		addrlen = sizeof (struct sockaddr_in);
630 		break;
631 #endif
632 
633 #ifdef NETISO
634 	  case AF_ISO:
635 		/* assume two byte transport selector */
636 		bcopy((char *) &port, TSEL((struct sockaddr_iso *) &addr), 2);
637 		addrlen = sizeof (struct sockaddr_iso);
638 		break;
639 #endif
640 
641 	  default:
642 		syserr("Can't connect to address family %d", addr.sa.sa_family);
643 		return (EX_NOHOST);
644 	}
645 
646 	/*
647 	**  Try to actually open the connection.
648 	*/
649 
650 #ifdef XLA
651 	/* if too many connections, don't bother trying */
652 	if (!xla_noqueue_ok(host))
653 		return EX_TEMPFAIL;
654 #endif
655 
656 	for (;;)
657 	{
658 		if (tTd(16, 1))
659 			printf("makeconnection (%s [%s])\n",
660 				host, anynet_ntoa(&addr));
661 
662 		/* save for logging */
663 		CurHostAddr = addr;
664 
665 		if (usesecureport)
666 		{
667 			int rport = IPPORT_RESERVED - 1;
668 
669 			s = rresvport(&rport);
670 		}
671 		else
672 		{
673 			s = socket(AF_INET, SOCK_STREAM, 0);
674 		}
675 		if (s < 0)
676 		{
677 			sav_errno = errno;
678 			syserr("makeconnection: no socket");
679 			goto failure;
680 		}
681 
682 #ifdef SO_SNDBUF
683 		if (TcpSndBufferSize > 0)
684 		{
685 			if (setsockopt(s, SOL_SOCKET, SO_SNDBUF,
686 				       (char *) &TcpSndBufferSize,
687 				       sizeof(TcpSndBufferSize)) < 0)
688 				syserr("makeconnection: setsockopt(SO_SNDBUF)");
689 		}
690 #endif
691 
692 		if (tTd(16, 1))
693 			printf("makeconnection: fd=%d\n", s);
694 
695 		/* turn on network debugging? */
696 		if (tTd(16, 101))
697 		{
698 			int on = 1;
699 			(void) setsockopt(DaemonSocket, SOL_SOCKET, SO_DEBUG,
700 					  (char *)&on, sizeof on);
701 		}
702 		if (CurEnv->e_xfp != NULL)
703 			(void) fflush(CurEnv->e_xfp);		/* for debugging */
704 		errno = 0;					/* for debugging */
705 		if (connect(s, (struct sockaddr *) &addr, addrlen) >= 0)
706 			break;
707 
708 		/* couldn't connect.... figure out why */
709 		sav_errno = errno;
710 		(void) close(s);
711 		if (hp && hp->h_addr_list[i])
712 		{
713 			if (tTd(16, 1))
714 				printf("Connect failed (%s); trying new address....\n",
715 					errstring(sav_errno));
716 			switch (addr.sa.sa_family)
717 			{
718 #ifdef NETINET
719 			  case AF_INET:
720 				bcopy(hp->h_addr_list[i++],
721 				      &addr.sin.sin_addr,
722 				      sizeof addr.sin.sin_addr);
723 				break;
724 #endif
725 
726 			  default:
727 				bcopy(hp->h_addr_list[i++],
728 					addr.sa.sa_data,
729 					hp->h_length);
730 				break;
731 			}
732 			continue;
733 		}
734 
735 		/* failure, decide if temporary or not */
736 	failure:
737 #ifdef XLA
738 		xla_host_end(host);
739 #endif
740 		if (transienterror(sav_errno))
741 			return EX_TEMPFAIL;
742 		else
743 		{
744 			message("%s", errstring(sav_errno));
745 			return (EX_UNAVAILABLE);
746 		}
747 	}
748 
749 	/* connection ok, put it into canonical form */
750 	if ((mci->mci_out = fdopen(s, "w")) == NULL ||
751 	    (s = dup(s)) < 0 ||
752 	    (mci->mci_in = fdopen(s, "r")) == NULL)
753 	{
754 		syserr("cannot open SMTP client channel, fd=%d", s);
755 		return EX_TEMPFAIL;
756 	}
757 
758 	return (EX_OK);
759 }
760 /*
761 **  MYHOSTNAME -- return the name of this host.
762 **
763 **	Parameters:
764 **		hostbuf -- a place to return the name of this host.
765 **		size -- the size of hostbuf.
766 **
767 **	Returns:
768 **		A list of aliases for this host.
769 **
770 **	Side Effects:
771 **		Adds numeric codes to $=w.
772 */
773 
774 char **
775 myhostname(hostbuf, size)
776 	char hostbuf[];
777 	int size;
778 {
779 	register struct hostent *hp;
780 	extern struct hostent *gethostbyname();
781 
782 	if (gethostname(hostbuf, size) < 0)
783 	{
784 		(void) strcpy(hostbuf, "localhost");
785 	}
786 	hp = gethostbyname(hostbuf);
787 	if (hp != NULL)
788 	{
789 		(void) strncpy(hostbuf, hp->h_name, size - 1);
790 		hostbuf[size - 1] = '\0';
791 
792 		if (hp->h_addrtype == AF_INET && hp->h_length == 4)
793 		{
794 			register int i;
795 
796 			for (i = 0; hp->h_addr_list[i] != NULL; i++)
797 			{
798 				char ipbuf[100];
799 
800 				sprintf(ipbuf, "[%s]",
801 					inet_ntoa(*((struct in_addr *) hp->h_addr_list[i])));
802 				setclass('w', ipbuf);
803 			}
804 		}
805 
806 		return (hp->h_aliases);
807 	}
808 	else
809 		return (NULL);
810 }
811 /*
812 **  GETAUTHINFO -- get the real host name asociated with a file descriptor
813 **
814 **	Uses RFC1413 protocol to try to get info from the other end.
815 **
816 **	Parameters:
817 **		fd -- the descriptor
818 **
819 **	Returns:
820 **		The user@host information associated with this descriptor.
821 */
822 
823 #if IDENTPROTO
824 
825 static jmp_buf	CtxAuthTimeout;
826 
827 static
828 authtimeout()
829 {
830 	longjmp(CtxAuthTimeout, 1);
831 }
832 
833 #endif
834 
835 char *
836 getauthinfo(fd)
837 	int fd;
838 {
839 	SOCKADDR fa;
840 	int falen;
841 	register char *p;
842 #if IDENTPROTO
843 	SOCKADDR la;
844 	int lalen;
845 	register struct servent *sp;
846 	int s;
847 	int i;
848 	EVENT *ev;
849 #endif
850 	static char hbuf[MAXNAME * 2 + 2];
851 	extern char *hostnamebyanyaddr();
852 	extern char RealUserName[];			/* main.c */
853 
854 	falen = sizeof fa;
855 	if (getpeername(fd, &fa.sa, &falen) < 0 || falen <= 0 ||
856 	    fa.sa.sa_family == 0)
857 	{
858 		(void) sprintf(hbuf, "%s@localhost", RealUserName);
859 		if (tTd(9, 1))
860 			printf("getauthinfo: %s\n", hbuf);
861 		return hbuf;
862 	}
863 
864 #if IDENTPROTO
865 	if (TimeOuts.to_ident == 0)
866 		goto noident;
867 
868 	lalen = sizeof la;
869 	if (fa.sa.sa_family != AF_INET ||
870 	    getsockname(fd, &la.sa, &lalen) < 0 || lalen <= 0 ||
871 	    la.sa.sa_family != AF_INET)
872 	{
873 		/* no ident info */
874 		goto noident;
875 	}
876 
877 	/* create ident query */
878 	(void) sprintf(hbuf, "%d,%d\r\n",
879 		ntohs(fa.sin.sin_port), ntohs(la.sin.sin_port));
880 
881 	/* create local address */
882 	la.sin.sin_port = 0;
883 
884 	/* create foreign address */
885 	sp = getservbyname("auth", "tcp");
886 	if (sp != NULL)
887 		fa.sin.sin_port = sp->s_port;
888 	else
889 		fa.sin.sin_port = htons(113);
890 
891 	s = -1;
892 	if (setjmp(CtxAuthTimeout) != 0)
893 	{
894 		if (s >= 0)
895 			(void) close(s);
896 		goto noident;
897 	}
898 
899 	/* put a timeout around the whole thing */
900 	ev = setevent(TimeOuts.to_ident, authtimeout, 0);
901 
902 	/* connect to foreign IDENT server using same address as SMTP socket */
903 	s = socket(AF_INET, SOCK_STREAM, 0);
904 	if (s < 0)
905 	{
906 		clrevent(ev);
907 		goto noident;
908 	}
909 	if (bind(s, &la.sa, sizeof la.sin) < 0 ||
910 	    connect(s, &fa.sa, sizeof fa.sin) < 0)
911 	{
912 		goto closeident;
913 	}
914 
915 	if (tTd(9, 10))
916 		printf("getauthinfo: sent %s", hbuf);
917 
918 	/* send query */
919 	if (write(s, hbuf, strlen(hbuf)) < 0)
920 		goto closeident;
921 
922 	/* get result */
923 	i = read(s, hbuf, sizeof hbuf);
924 	(void) close(s);
925 	clrevent(ev);
926 	if (i <= 0)
927 		goto noident;
928 	if (hbuf[--i] == '\n' && hbuf[--i] == '\r')
929 		i--;
930 	hbuf[++i] = '\0';
931 
932 	if (tTd(9, 3))
933 		printf("getauthinfo:  got %s\n", hbuf);
934 
935 	/* parse result */
936 	p = strchr(hbuf, ':');
937 	if (p == NULL)
938 	{
939 		/* malformed response */
940 		goto noident;
941 	}
942 	while (isascii(*++p) && isspace(*p))
943 		continue;
944 	if (strncasecmp(p, "userid", 6) != 0)
945 	{
946 		/* presumably an error string */
947 		goto noident;
948 	}
949 	p += 6;
950 	while (isascii(*p) && isspace(*p))
951 		p++;
952 	if (*p++ != ':')
953 	{
954 		/* either useridxx or malformed response */
955 		goto noident;
956 	}
957 
958 	/* p now points to the OSTYPE field */
959 	p = strchr(p, ':');
960 	if (p == NULL)
961 	{
962 		/* malformed response */
963 		goto noident;
964 	}
965 
966 	/* 1413 says don't do this -- but it's broken otherwise */
967 	while (isascii(*++p) && isspace(*p))
968 		continue;
969 
970 	/* p now points to the authenticated name */
971 	(void) sprintf(hbuf, "%s@%s",
972 		p, RealHostName == NULL ? "localhost" : RealHostName);
973 	goto finish;
974 
975 closeident:
976 	(void) close(s);
977 	clrevent(ev);
978 
979 #endif /* IDENTPROTO */
980 
981 noident:
982 	if (RealHostName == NULL)
983 	{
984 		if (tTd(9, 1))
985 			printf("getauthinfo: NULL\n");
986 		return NULL;
987 	}
988 	(void) strcpy(hbuf, RealHostName);
989 
990 finish:
991 	if (RealHostName != NULL && RealHostName[0] != '[')
992 	{
993 		p = &hbuf[strlen(hbuf)];
994 		(void) sprintf(p, " [%s]", anynet_ntoa(&RealHostAddr));
995 	}
996 	if (tTd(9, 1))
997 		printf("getauthinfo: %s\n", hbuf);
998 	return hbuf;
999 }
1000 /*
1001 **  HOST_MAP_LOOKUP -- turn a hostname into canonical form
1002 **
1003 **	Parameters:
1004 **		map -- a pointer to this map (unused).
1005 **		name -- the (presumably unqualified) hostname.
1006 **		av -- unused -- for compatibility with other mapping
1007 **			functions.
1008 **		statp -- an exit status (out parameter) -- set to
1009 **			EX_TEMPFAIL if the name server is unavailable.
1010 **
1011 **	Returns:
1012 **		The mapping, if found.
1013 **		NULL if no mapping found.
1014 **
1015 **	Side Effects:
1016 **		Looks up the host specified in hbuf.  If it is not
1017 **		the canonical name for that host, return the canonical
1018 **		name.
1019 */
1020 
1021 char *
1022 host_map_lookup(map, name, av, statp)
1023 	MAP *map;
1024 	char *name;
1025 	char **av;
1026 	int *statp;
1027 {
1028 	register struct hostent *hp;
1029 	u_long in_addr;
1030 	char *cp;
1031 	int i;
1032 	register STAB *s;
1033 	char hbuf[MAXNAME];
1034 	extern struct hostent *gethostbyaddr();
1035 	extern int h_errno;
1036 
1037 	/*
1038 	**  See if we have already looked up this name.  If so, just
1039 	**  return it.
1040 	*/
1041 
1042 	s = stab(name, ST_NAMECANON, ST_ENTER);
1043 	if (bitset(NCF_VALID, s->s_namecanon.nc_flags))
1044 	{
1045 		if (tTd(9, 1))
1046 			printf("host_map_lookup(%s) => CACHE %s\n",
1047 				name, s->s_namecanon.nc_cname);
1048 		errno = s->s_namecanon.nc_errno;
1049 		h_errno = s->s_namecanon.nc_herrno;
1050 		*statp = s->s_namecanon.nc_stat;
1051 		if (CurEnv->e_message == NULL && *statp == EX_TEMPFAIL)
1052 		{
1053 			sprintf(hbuf, "%s: Name server timeout",
1054 				shortenstring(name, 33));
1055 			CurEnv->e_message = newstr(hbuf);
1056 		}
1057 		return s->s_namecanon.nc_cname;
1058 	}
1059 
1060 	/*
1061 	**  If first character is a bracket, then it is an address
1062 	**  lookup.  Address is copied into a temporary buffer to
1063 	**  strip the brackets and to preserve name if address is
1064 	**  unknown.
1065 	*/
1066 
1067 	if (*name != '[')
1068 	{
1069 		extern bool getcanonname();
1070 
1071 		if (tTd(9, 1))
1072 			printf("host_map_lookup(%s) => ", name);
1073 		s->s_namecanon.nc_flags |= NCF_VALID;		/* will be soon */
1074 		(void) strcpy(hbuf, name);
1075 		if (getcanonname(hbuf, sizeof hbuf - 1, TRUE))
1076 		{
1077 			if (tTd(9, 1))
1078 				printf("%s\n", hbuf);
1079 			cp = map_rewrite(map, hbuf, strlen(hbuf), av);
1080 			s->s_namecanon.nc_cname = newstr(cp);
1081 			return cp;
1082 		}
1083 		else
1084 		{
1085 			register struct hostent *hp;
1086 
1087 			if (tTd(9, 1))
1088 				printf("FAIL (%d)\n", h_errno);
1089 			s->s_namecanon.nc_errno = errno;
1090 			s->s_namecanon.nc_herrno = h_errno;
1091 			switch (h_errno)
1092 			{
1093 			  case TRY_AGAIN:
1094 				if (UseNameServer)
1095 				{
1096 					sprintf(hbuf, "%s: Name server timeout",
1097 						shortenstring(name, 33));
1098 					message("%s", hbuf);
1099 					if (CurEnv->e_message == NULL)
1100 						CurEnv->e_message = newstr(hbuf);
1101 				}
1102 				*statp = EX_TEMPFAIL;
1103 				break;
1104 
1105 			  case HOST_NOT_FOUND:
1106 				*statp = EX_NOHOST;
1107 				break;
1108 
1109 			  case NO_RECOVERY:
1110 				*statp = EX_SOFTWARE;
1111 				break;
1112 
1113 			  default:
1114 				*statp = EX_UNAVAILABLE;
1115 				break;
1116 			}
1117 			s->s_namecanon.nc_stat = *statp;
1118 			if (*statp != EX_TEMPFAIL || UseNameServer)
1119 				return NULL;
1120 
1121 			/*
1122 			**  Try to look it up in /etc/hosts
1123 			*/
1124 
1125 			hp = gethostbyname(name);
1126 			if (hp == NULL)
1127 			{
1128 				/* no dice there either */
1129 				s->s_namecanon.nc_stat = *statp = EX_NOHOST;
1130 				return NULL;
1131 			}
1132 
1133 			s->s_namecanon.nc_stat = *statp = EX_OK;
1134 			cp = map_rewrite(map, hp->h_name, strlen(hp->h_name), av);
1135 			s->s_namecanon.nc_cname = newstr(cp);
1136 			return cp;
1137 		}
1138 	}
1139 	if ((cp = strchr(name, ']')) == NULL)
1140 		return (NULL);
1141 	*cp = '\0';
1142 	in_addr = inet_addr(&name[1]);
1143 
1144 	/* nope -- ask the name server */
1145 	hp = gethostbyaddr((char *)&in_addr, sizeof(struct in_addr), AF_INET);
1146 	s->s_namecanon.nc_errno = errno;
1147 	s->s_namecanon.nc_herrno = h_errno;
1148 	s->s_namecanon.nc_flags |= NCF_VALID;		/* will be soon */
1149 	if (hp == NULL)
1150 	{
1151 		s->s_namecanon.nc_stat = *statp = EX_NOHOST;
1152 		return (NULL);
1153 	}
1154 
1155 	/* found a match -- copy out */
1156 	cp = map_rewrite(map, hp->h_name, strlen(hp->h_name), av);
1157 	s->s_namecanon.nc_stat = *statp = EX_OK;
1158 	s->s_namecanon.nc_cname = newstr(cp);
1159 	return cp;
1160 }
1161 /*
1162 **  ANYNET_NTOA -- convert a network address to printable form.
1163 **
1164 **	Parameters:
1165 **		sap -- a pointer to a sockaddr structure.
1166 **
1167 **	Returns:
1168 **		A printable version of that sockaddr.
1169 */
1170 
1171 char *
1172 anynet_ntoa(sap)
1173 	register SOCKADDR *sap;
1174 {
1175 	register char *bp;
1176 	register char *ap;
1177 	int l;
1178 	static char buf[100];
1179 
1180 	/* check for null/zero family */
1181 	if (sap == NULL)
1182 		return "NULLADDR";
1183 	if (sap->sa.sa_family == 0)
1184 		return "0";
1185 
1186 	switch (sap->sa.sa_family)
1187 	{
1188 #ifdef MAYBENEXTRELEASE		/*** UNTESTED *** UNTESTED *** UNTESTED ***/
1189 #ifdef NETUNIX
1190 	  case AF_UNIX:
1191 	  	if (sap->sunix.sun_path[0] != '\0')
1192 	  		sprintf(buf, "[UNIX: %.64s]", sap->sunix.sun_path);
1193 	  	else
1194 	  		sprintf(buf, "[UNIX: localhost]");
1195 		return buf;
1196 #endif
1197 #endif
1198 
1199 #ifdef NETINET
1200 	  case AF_INET:
1201 		return inet_ntoa(((struct sockaddr_in *) sap)->sin_addr);
1202 #endif
1203 
1204 	  default:
1205 	  	/* this case is only to ensure syntactic correctness */
1206 	  	break;
1207 	}
1208 
1209 	/* unknown family -- just dump bytes */
1210 	(void) sprintf(buf, "Family %d: ", sap->sa.sa_family);
1211 	bp = &buf[strlen(buf)];
1212 	ap = sap->sa.sa_data;
1213 	for (l = sizeof sap->sa.sa_data; --l >= 0; )
1214 	{
1215 		(void) sprintf(bp, "%02x:", *ap++ & 0377);
1216 		bp += 3;
1217 	}
1218 	*--bp = '\0';
1219 	return buf;
1220 }
1221 /*
1222 **  HOSTNAMEBYANYADDR -- return name of host based on address
1223 **
1224 **	Parameters:
1225 **		sap -- SOCKADDR pointer
1226 **
1227 **	Returns:
1228 **		text representation of host name.
1229 **
1230 **	Side Effects:
1231 **		none.
1232 */
1233 
1234 char *
1235 hostnamebyanyaddr(sap)
1236 	register SOCKADDR *sap;
1237 {
1238 	register struct hostent *hp;
1239 	int saveretry;
1240 
1241 #ifdef NAMED_BIND
1242 	/* shorten name server timeout to avoid higher level timeouts */
1243 	saveretry = _res.retry;
1244 	_res.retry = 3;
1245 #endif /* NAMED_BIND */
1246 
1247 	switch (sap->sa.sa_family)
1248 	{
1249 #ifdef NETINET
1250 	  case AF_INET:
1251 		hp = gethostbyaddr((char *) &sap->sin.sin_addr,
1252 			sizeof sap->sin.sin_addr,
1253 			AF_INET);
1254 		break;
1255 #endif
1256 
1257 #ifdef NETISO
1258 	  case AF_ISO:
1259 		hp = gethostbyaddr((char *) &sap->siso.siso_addr,
1260 			sizeof sap->siso.siso_addr,
1261 			AF_ISO);
1262 		break;
1263 #endif
1264 
1265 #ifdef MAYBENEXTRELEASE		/*** UNTESTED *** UNTESTED *** UNTESTED ***/
1266 	  case AF_UNIX:
1267 		hp = NULL;
1268 		break;
1269 #endif
1270 
1271 	  default:
1272 		hp = gethostbyaddr(sap->sa.sa_data,
1273 			   sizeof sap->sa.sa_data,
1274 			   sap->sa.sa_family);
1275 		break;
1276 	}
1277 
1278 #ifdef NAMED_BIND
1279 	_res.retry = saveretry;
1280 #endif /* NAMED_BIND */
1281 
1282 	if (hp != NULL)
1283 		return hp->h_name;
1284 	else
1285 	{
1286 		/* produce a dotted quad */
1287 		static char buf[512];
1288 
1289 		(void) sprintf(buf, "[%s]", anynet_ntoa(sap));
1290 		return buf;
1291 	}
1292 }
1293 
1294 # else /* DAEMON */
1295 /* code for systems without sophisticated networking */
1296 
1297 /*
1298 **  MYHOSTNAME -- stub version for case of no daemon code.
1299 **
1300 **	Can't convert to upper case here because might be a UUCP name.
1301 **
1302 **	Mark, you can change this to be anything you want......
1303 */
1304 
1305 char **
1306 myhostname(hostbuf, size)
1307 	char hostbuf[];
1308 	int size;
1309 {
1310 	register FILE *f;
1311 
1312 	hostbuf[0] = '\0';
1313 	f = fopen("/usr/include/whoami", "r");
1314 	if (f != NULL)
1315 	{
1316 		(void) fgets(hostbuf, size, f);
1317 		fixcrlf(hostbuf, TRUE);
1318 		(void) fclose(f);
1319 	}
1320 	return (NULL);
1321 }
1322 /*
1323 **  GETAUTHINFO -- get the real host name asociated with a file descriptor
1324 **
1325 **	Parameters:
1326 **		fd -- the descriptor
1327 **
1328 **	Returns:
1329 **		The host name associated with this descriptor, if it can
1330 **			be determined.
1331 **		NULL otherwise.
1332 **
1333 **	Side Effects:
1334 **		none
1335 */
1336 
1337 char *
1338 getauthinfo(fd)
1339 	int fd;
1340 {
1341 	return NULL;
1342 }
1343 /*
1344 **  MAPHOSTNAME -- turn a hostname into canonical form
1345 **
1346 **	Parameters:
1347 **		map -- a pointer to the database map.
1348 **		name -- a buffer containing a hostname.
1349 **		avp -- a pointer to a (cf file defined) argument vector.
1350 **		statp -- an exit status (out parameter).
1351 **
1352 **	Returns:
1353 **		mapped host name
1354 **		FALSE otherwise.
1355 **
1356 **	Side Effects:
1357 **		Looks up the host specified in name.  If it is not
1358 **		the canonical name for that host, replace it with
1359 **		the canonical name.  If the name is unknown, or it
1360 **		is already the canonical name, leave it unchanged.
1361 */
1362 
1363 /*ARGSUSED*/
1364 char *
1365 host_map_lookup(map, name, avp, statp)
1366 	MAP *map;
1367 	char *name;
1368 	char **avp;
1369 	char *statp;
1370 {
1371 	register struct hostent *hp;
1372 
1373 	hp = gethostbyname(name);
1374 	if (hp != NULL)
1375 		return hp->h_name;
1376 	*statp = EX_NOHOST;
1377 	return NULL;
1378 }
1379 
1380 #endif /* DAEMON */
1381