16039Seric # include <errno.h>
24535Seric # include "sendmail.h"
34535Seric 
45978Seric #ifndef DAEMON
5*7892Seric SCCSID(@(#)daemon.c	3.27		08/25/82	(w/o daemon mode));
65978Seric #else
74535Seric 
85978Seric # include <sys/socket.h>
95978Seric # include <net/in.h>
107117Seric # include <wait.h>
115978Seric 
12*7892Seric SCCSID(@(#)daemon.c	3.27		08/25/82	(with daemon mode));
135978Seric 
144535Seric /*
154535Seric **  DAEMON.C -- routines to use when running as a daemon.
167556Seric **
177556Seric **	This entire file is highly dependent on the 4.2 BSD
187556Seric **	interprocess communication primitives.  No attempt has
197556Seric **	been made to make this file portable to Version 7,
207556Seric **	Version 6, MPX files, etc.  If you should try such a
217556Seric **	thing yourself, I recommend chucking the entire file
227556Seric **	and starting from scratch.  Basic semantics are:
237556Seric **
247556Seric **	getrequests()
257556Seric **		Opens a port and initiates a connection.
267556Seric **		Returns in a child.  Must set InChannel and
277556Seric **		OutChannel appropriately.
287556Seric **	makeconnection(host, port, outfile, infile)
297556Seric **		Make a connection to the named host on the given
307556Seric **		port.  Set *outfile and *infile to the files
317556Seric **		appropriate for communication.  Returns zero on
327556Seric **		success, else an exit status describing the
337556Seric **		error.
347556Seric **
357556Seric **	The semantics of both of these should be clean.
364535Seric */
374535Seric /*
384535Seric **  GETREQUESTS -- open mail IPC port and get requests.
394535Seric **
404535Seric **	Parameters:
414535Seric **		none.
424535Seric **
434535Seric **	Returns:
444535Seric **		none.
454535Seric **
464535Seric **	Side Effects:
474535Seric **		Waits until some interesting activity occurs.  When
484535Seric **		it does, a child is created to process it, and the
494535Seric **		parent waits for completion.  Return from this
504535Seric **		routine is always in the child.
514535Seric */
524535Seric 
537117Seric # define MAXCONNS	4	/* maximum simultaneous sendmails */
547117Seric 
554535Seric getrequests()
564535Seric {
577117Seric 	union wait status;
587117Seric 	int numconnections = 0;
597117Seric 
604631Seric 	for (;;)
614631Seric 	{
624636Seric 		register int pid;
635978Seric 		register int port;
644631Seric 
654636Seric 		/*
664636Seric 		**  Wait for a connection.
674636Seric 		*/
684631Seric 
695978Seric 		while ((port = getconnection()) < 0)
705978Seric 		{
715978Seric 			syserr("getrequests: getconnection failed");
727556Seric 			finis();
735978Seric 		}
744631Seric 
755978Seric 		/*
765978Seric 		**  Create a subprocess to process the mail.
775978Seric 		*/
785978Seric 
795978Seric # ifdef DEBUG
807677Seric 		if (tTd(15, 2))
815978Seric 			printf("getrequests: forking (port = %d)\n", port);
825978Seric # endif DEBUG
835978Seric 
844636Seric 		pid = fork();
854636Seric 		if (pid < 0)
864631Seric 		{
874636Seric 			syserr("daemon: cannot fork");
884636Seric 			sleep(10);
897009Seric 			(void) close(port);
904636Seric 			continue;
914631Seric 		}
924631Seric 
934636Seric 		if (pid == 0)
944631Seric 		{
954636Seric 			/*
964636Seric 			**  CHILD -- return to caller.
974636Seric 			**	Verify calling user id if possible here.
984636Seric 			*/
994631Seric 
1005978Seric 			InChannel = fdopen(port, "r");
1015978Seric 			OutChannel = fdopen(port, "w");
1025978Seric # ifdef DEBUG
1037677Seric 			if (tTd(15, 2))
1045978Seric 				printf("getreq: returning\n");
1055978Seric # endif DEBUG
1067876Seric # ifdef LOG
1077876Seric 			if (LogLevel > 11)
1087876Seric 				syslog(LOG_DEBUG, "connected, pid=%d", getpid());
1097876Seric # endif LOG
1104636Seric 			return;
1114631Seric 		}
1124631Seric 
1134636Seric 		/*
1144636Seric 		**  PARENT -- wait for child to terminate.
1154636Seric 		**	Perhaps we should allow concurrent processing?
1164636Seric 		*/
1174631Seric 
1185978Seric # ifdef DEBUG
1197677Seric 		if (tTd(15, 2))
1205978Seric 		{
1215978Seric 			sleep(2);
1225978Seric 			printf("getreq: parent waiting\n");
1235978Seric 		}
1245978Seric # endif DEBUG
1255978Seric 
1267117Seric 		/* close the port so that others will hang (for a while) */
1277009Seric 		(void) close(port);
1287117Seric 
1297117Seric 		/* pick up old zombies; implement load limiting */
1307117Seric 		numconnections++;
1317117Seric 		while (wait3(&status, numconnections < MAXCONNS ? WNOHANG : 0, 0) > 0)
1327117Seric 			numconnections--;
1334631Seric 	}
1344631Seric }
1355978Seric /*
1365978Seric **  GETCONNECTION -- make a connection with the outside world
1375978Seric **
1385978Seric **	Parameters:
1395978Seric **		none.
1405978Seric **
1415978Seric **	Returns:
1425978Seric **		The port for mail traffic.
1435978Seric **
1445978Seric **	Side Effects:
1455978Seric **		Waits for a connection.
1465978Seric */
1475978Seric 
1487117Seric #define IPPORT_PLAYPORT	3055		/* random number */
1497117Seric 
1505979Seric struct sockaddr_in SendmailAddress = { AF_INET, IPPORT_SMTP };
1515978Seric 
1525978Seric getconnection()
1535978Seric {
1545978Seric 	register int s;
1555978Seric 	struct sockaddr otherend;
1565978Seric 
1575978Seric 	/*
1585978Seric 	**  Set up the address for the mailer.
1595978Seric 	*/
1605978Seric 
1616058Seric 	SendmailAddress.sin_addr.s_addr = 0;
1626633Seric 	SendmailAddress.sin_port = IPPORT_SMTP;
1637117Seric # ifdef DEBUG
1647677Seric 	if (tTd(15, 15))
1657117Seric 		SendmailAddress.sin_port = IPPORT_PLAYPORT;
1667117Seric # endif DEBUG
1677117Seric 	SendmailAddress.sin_port = htons(SendmailAddress.sin_port);
1685978Seric 
1695978Seric 	/*
1705978Seric 	**  Try to actually open the connection.
1715978Seric 	*/
1725978Seric 
1735978Seric # ifdef DEBUG
1747677Seric 	if (tTd(15, 1))
1756058Seric 		printf("getconnection\n");
1765978Seric # endif DEBUG
1775978Seric 
178*7892Seric 	for (;; sleep(10))
1797117Seric 	{
1807556Seric 		/* get a socket for the SMTP connection */
1817556Seric 		s = socket(SOCK_STREAM, 0, &SendmailAddress, SO_ACCEPTCONN);
1827556Seric 		if (s < 0)
1837556Seric 		{
1847556Seric 			/* probably another daemon already */
1857556Seric 			syserr("getconnection: can't create socket");
186*7892Seric 			return (-1);
1877556Seric 		}
1885978Seric 
1895978Seric # ifdef DEBUG
1907677Seric 		if (tTd(15, 1))
1917556Seric 			printf("getconnection: %d\n", s);
1925978Seric # endif DEBUG
1937556Seric 
1947556Seric 		/* wait for a connection */
195*7892Seric 		do
196*7892Seric 		{
197*7892Seric 			errno = 0;
198*7892Seric 			if (accept(s, &otherend) >= 0)
199*7892Seric 				return (s);
200*7892Seric 		} while (errno == EINTR);
2017556Seric 		syserr("getconnection: accept");
2027286Seric 		(void) close(s);
2037117Seric 	}
2045978Seric }
2056039Seric /*
2066039Seric **  MAKECONNECTION -- make a connection to an SMTP socket on another machine.
2076039Seric **
2086039Seric **	Parameters:
2096039Seric **		host -- the name of the host.
2106633Seric **		port -- the port number to connect to.
2116039Seric **		outfile -- a pointer to a place to put the outfile
2126039Seric **			descriptor.
2136039Seric **		infile -- ditto for infile.
2146039Seric **
2156039Seric **	Returns:
2166039Seric **		An exit code telling whether the connection could be
2176039Seric **			made and if not why not.
2186039Seric **
2196039Seric **	Side Effects:
2206039Seric **		none.
2216039Seric */
2225978Seric 
2236633Seric makeconnection(host, port, outfile, infile)
2246039Seric 	char *host;
2257286Seric 	u_short port;
2266039Seric 	FILE **outfile;
2276039Seric 	FILE **infile;
2286039Seric {
2296039Seric 	register int s;
2306039Seric 
2316039Seric 	/*
2326039Seric 	**  Set up the address for the mailer.
2336039Seric 	*/
2346039Seric 
2356039Seric 	if ((SendmailAddress.sin_addr.s_addr = rhost(&host)) == -1)
2366039Seric 		return (EX_NOHOST);
2376633Seric 	if (port == 0)
2386633Seric 		port = IPPORT_SMTP;
2397117Seric 	SendmailAddress.sin_port = htons(port);
2406039Seric 
2416039Seric 	/*
2426039Seric 	**  Try to actually open the connection.
2436039Seric 	*/
2446039Seric 
2456039Seric # ifdef DEBUG
2467677Seric 	if (tTd(16, 1))
2476039Seric 		printf("makeconnection (%s)\n", host);
2486039Seric # endif DEBUG
2496039Seric 
2507009Seric 	s = socket(SOCK_STREAM, 0, (struct sockaddr_in *) 0, 0);
2516039Seric 	if (s < 0)
2526039Seric 	{
2536039Seric 		syserr("makeconnection: no socket");
2546039Seric 		goto failure;
2556039Seric 	}
2566039Seric 
2576039Seric # ifdef DEBUG
2587677Seric 	if (tTd(16, 1))
2596039Seric 		printf("makeconnection: %d\n", s);
2606039Seric # endif DEBUG
2617677Seric 	(void) fflush(Xscript);				/* for debugging */
2626039Seric 	if (connect(s, &SendmailAddress) < 0)
2636039Seric 	{
2646039Seric 		/* failure, decide if temporary or not */
2656039Seric 	failure:
2666039Seric 		switch (errno)
2676039Seric 		{
2686039Seric 		  case EISCONN:
2696039Seric 		  case ETIMEDOUT:
2706897Seric 		  case EINPROGRESS:
2716897Seric 		  case EALREADY:
2726897Seric 		  case EADDRINUSE:
2736897Seric 		  case ENETDOWN:
2746897Seric 		  case ENETRESET:
2756897Seric 		  case ENOBUFS:
2767204Seric 		  case ECONNREFUSED:
2776039Seric 			/* there are others, I'm sure..... */
2786039Seric 			return (EX_TEMPFAIL);
2796039Seric 
2806039Seric 		  default:
2816039Seric 			return (EX_UNAVAILABLE);
2826039Seric 		}
2836039Seric 	}
2846039Seric 
2856039Seric 	/* connection ok, put it into canonical form */
2866039Seric 	*outfile = fdopen(s, "w");
2876039Seric 	*infile = fdopen(s, "r");
2886039Seric 
2896039Seric 	return (0);
2906039Seric }
2916039Seric 
2925978Seric #endif DAEMON
293