deliver.c

<B>Digital的Unix操作系统VAX 4.2源码</B>

**		q -- the address to mark.
**		rcode -- the code signifying the particular failure.
**
**	Returns:
**		none.
**
**	Side Effects:
**		marks the address (and possibly the envelope) with the
**			failure so that an error will be returned or
**			the message will be queued, as appropriate.
*/

markfailure(e, q, rcode)
	register ENVELOPE *e;
	register ADDRESS *q;
	int rcode;
{
	if (rcode == EX_OK)
		return;
	else if (rcode != EX_TEMPFAIL)
		q->q_flags |= QBADADDR;
	else if (curtime() > e->e_ctime + TimeOut)
	{
		extern char *pintvl();
		char buf[MAXLINE];

		if (!bitset(EF_TIMEOUT, e->e_flags))
		{
			(void) sprintf(buf, "Cannot send message for %s",
				pintvl(TimeOut, FALSE));
			if (e->e_message != NULL)
				free(e->e_message);
			e->e_message = newstr(buf);
			message(Arpa_Info, buf);
		}
		q->q_flags |= QBADADDR;
		e->e_flags |= EF_TIMEOUT;
	}
	else
		q->q_flags |= QQUEUEUP;
}
/*
**  DOFORK -- do a fork, retrying a couple of times on failure.
**
**	This MUST be a macro, since after a vfork we are running
**	two processes on the same stack!!!
**
**	Parameters:
**		none.
**
**	Returns:
**		From a macro???  You've got to be kidding!
**
**	Side Effects:
**		Modifies the ==> LOCAL <== variable 'pid', leaving:
**			pid of child in parent, zero in child.
**			-1 on unrecoverable error.
**
**	Notes:
**		I'm awfully sorry this looks so awful.  That's
**		vfork for you.....
*/

# define NFORKTRIES	5
# ifdef VMUNIX
# define XFORK	vfork
# else VMUNIX
# define XFORK	fork
# endif VMUNIX

# define DOFORK(fORKfN) \
{\
	register int i;\
\
	for (i = NFORKTRIES; --i >= 0; )\
	{\
		pid = fORKfN();\
		if (pid >= 0)\
			break;\
		if (i > 0)\
			sleep((unsigned) NFORKTRIES - i);\
	}\
}
/*
**  DOFORK -- simple fork interface to DOFORK.
**
**	Parameters:
**		none.
**
**	Returns:
**		pid of child in parent.
**		zero in child.
**		-1 on error.
**
**	Side Effects:
**		returns twice, once in parent and once in child.
*/

dofork()
{
	register int pid;

	DOFORK(fork);
	return (pid);
}
/*
**  SENDOFF -- send off call to mailer & collect response.
**
**	Parameters:
**		e -- the envelope to mail.
**		m -- mailer descriptor.
**		pvp -- parameter vector to send to it.
**		ctladdr -- an address pointer controlling the
**			user/groupid etc. of the mailer.
**
**	Returns:
**		exit status of mailer.
**
**	Side Effects:
**		none.
*/

sendoff(e, m, pvp, ctladdr)
	register ENVELOPE *e;
	MAILER *m;
	char **pvp;
	ADDRESS *ctladdr;
{
	auto FILE *mfile;
	auto FILE *rfile;
	register int i;
	int pid;

	/*
	**  Create connection to mailer.
	*/

	pid = openmailer(m, pvp, ctladdr, FALSE, &mfile, &rfile);
	if (pid < 0)
		return (-1);

	/*
	**  Format and send message.
	*/

	putfromline(mfile, m);
	(*e->e_puthdr)(mfile, m, e);
	putline("\n", mfile, m);
	(*e->e_putbody)(mfile, m, e);
	(void) fclose(mfile);

	i = endmailer(pid, pvp[0]);

	/* arrange a return receipt if requested */
	if (e->e_receiptto != NULL && bitnset(M_LOCAL, m->m_flags))
	{
		e->e_flags |= EF_SENDRECEIPT;
		/* do we want to send back more info? */
	}

	return (i);
}
/*
**  ENDMAILER -- Wait for mailer to terminate.
**
**	We should never get fatal errors (e.g., segmentation
**	violation), so we report those specially.  For other
**	errors, we choose a status message (into statmsg),
**	and if it represents an error, we print it.
**
**	Parameters:
**		pid -- pid of mailer.
**		name -- name of mailer (for error messages).
**
**	Returns:
**		exit code of mailer.
**
**	Side Effects:
**		none.
*/

endmailer(pid, name)
	int pid;
	char *name;
{
	int st;

	/* in the IPC case there is nothing to wait for */
	if (pid == 0)
		return (EX_OK);

	/* wait for the mailer process to die and collect status */
	st = waitfor(pid);
	if (st == -1)
	{
		syserr("endmailer %s: wait", name);
		return (EX_SOFTWARE);
	}

	/* see if it died a horrid death */
	if ((st & 0377) != 0)
	{
		syserr("mailer %s died with signal %o", name, st);
		ExitStat = EX_TEMPFAIL;
		return (EX_TEMPFAIL);
	}

	/* normal death -- return status */
	st = (st >> 8) & 0377;
	return (st);
}
/*
**  OPENMAILER -- open connection to mailer.
**
**	Parameters:
**		m -- mailer descriptor.
**		pvp -- parameter vector to pass to mailer.
**		ctladdr -- controlling address for user.
**		clever -- create a full duplex connection.
**		pmfile -- pointer to mfile (to mailer) connection.
**		prfile -- pointer to rfile (from mailer) connection.
**
**	Returns:
**		pid of mailer ( > 0 ).
**		-1 on error.
**		zero on an IPC connection.
**
**	Side Effects:
**		creates a mailer in a subprocess.
*/

openmailer(m, pvp, ctladdr, clever, pmfile, prfile)
	MAILER *m;
	char **pvp;
	ADDRESS *ctladdr;
	bool clever;
	FILE **pmfile;
	FILE **prfile;
{
	int pid;
	int mpvect[2];
	int rpvect[2];
	FILE *mfile;
	FILE *rfile;
	extern FILE *fdopen();

# ifdef DEBUG
	if (tTd(11, 1))
	{
		printf("openmailer:");
		printav(pvp);
	}
# endif DEBUG
	errno = 0;

	CurHostName = m->m_mailer;

	/*
	**  Deal with the special case of mail handled through an IPC
	**  connection.
	**	In this case we don't actually fork.  We must be
	**	running SMTP for this to work.  We will return a
	**	zero pid to indicate that we are running IPC.
	**  We also handle a debug version that just talks to stdin/out.
	*/

#ifdef DEBUG
	/* check for Local Person Communication -- not for mortals!!! */
	if (strcmp(m->m_mailer, "[LPC]") == 0)
	{
		*pmfile = stdout;
		*prfile = stdin;
		return (0);
	}
#endif DEBUG

	if (strcmp(m->m_mailer, "[IPC]") == 0)
	{
#ifdef HOSTINFO
		register STAB *st;
		extern STAB *stab();
#endif HOSTINFO
#ifdef DAEMON
		register int i, j;
		register u_short port;

		CurHostName = pvp[1];
		if (!clever)
			syserr("non-clever IPC");
		if (pvp[2] != NULL)
			port = atoi(pvp[2]);
		else
			port = 0;
		for (j = 0; j < nmx; j++)
		{
			CurHostName = mxhosts[j];
#ifdef HOSTINFO
		/* see if we have already determined that this host is fried */
			st = stab(mxhosts[j], ST_HOST, ST_FIND);
			if (st == NULL || st->s_host.ho_exitstat == EX_OK)
				i = makeconnection(mxhosts[j], port, pmfile, prfile);
			else
			{
				i = st->s_host.ho_exitstat;
				errno = st->s_host.ho_errno;
			}
#else HOSTINFO
			i = makeconnection(mxhosts[j], port, pmfile, prfile);
#endif HOSTINFO
			if (i != EX_OK)
			{
				/*
				 * Consider the case of multiple MX entries
				 * for a given host where the last entry refers
				 * to non-existent host.  On occasions when
				 * none of the hosts are reachable, the mail
				 * will bounce if the last ExitStat is
				 * EX_NOHOST.  Handle this by resetting i to
				 * EX_TEMPFAIL if it's not the primary MX entry
				 * and it's the last MX entry.  -pbp
				 */
#ifdef LOG
				if (i == EX_NOHOST)
					syslog(LOG_WARNING, "Found non-existent host %s in MX records for %s", CurHostName, pvp[1]);
#endif LOG
				if (j != 0 && j == (nmx - 1))
					i = EX_TEMPFAIL;
#ifdef HOSTINFO
				/* enter status of this host */
				if (st == NULL)
					st = stab(mxhosts[j], ST_HOST, ST_ENTER);
				st->s_host.ho_exitstat = i;
				st->s_host.ho_errno = errno;
#endif HOSTINFO
				ExitStat = i;
				continue;
			}
			else
				return (0);
		}
		return (-1);
#else DAEMON
		syserr("openmailer: no IPC");
		return (-1);
#endif DAEMON
	}

	/* create a pipe to shove the mail through */
	if (pipe(mpvect) < 0)
	{
		syserr("openmailer: pipe (to mailer)");
		return (-1);
	}

#ifdef SMTP
	/* if this mailer speaks smtp, create a return pipe */
	if (clever && pipe(rpvect) < 0)
	{
		syserr("openmailer: pipe (from mailer)");
		(void) close(mpvect[0]);
		(void) close(mpvect[1]);
		return (-1);
	}
#endif SMTP

	/*
	**  Actually fork the mailer process.
	**	DOFORK is clever about retrying.
	**
	**	Dispose of SIGCHLD signal catchers that may be laying
	**	around so that endmail will get it.
	*/

	if (CurEnv->e_xfp != NULL)
		(void) fflush(CurEnv->e_xfp);		/* for debugging */
	(void) fflush(stdout);
# ifdef SIGCHLD
	(void) signal(SIGCHLD, SIG_DFL);
# endif SIGCHLD
	DOFORK(XFORK);
	/* pid is set by DOFORK */
	if (pid < 0)
	{
		/* failure */
		syserr("openmailer: cannot fork");
		(void) close(mpvect[0]);
		(void) close(mpvect[1]);
#ifdef SMTP
		if (clever)
		{
			(void) close(rpvect[0]);
			(void) close(rpvect[1]);
		}
#endif SMTP
		return (-1);
	}
	else if (pid == 0)
	{
		int i;
		extern int DtableSize;

		/* child -- set up input & exec mailer */
		/* make diagnostic output be standard output */
		(void) signal(SIGINT, SIG_IGN);
		(void) signal(SIGHUP, SIG_IGN);
		(void) signal(SIGTERM, SIG_DFL);

		/* arrange to filter standard & diag output of command */
		if (clever)
		{
			(void) close(rpvect[0]);
			(void) close(1);
			(void) dup(rpvect[1]);
			(void) close(rpvect[1]);
		}
		else if (OpMode == MD_SMTP || HoldErrs)
		{
			/* put mailer output in transcript */
			(void) close(1);
			(void) dup(fileno(CurEnv->e_xfp));
		}
		(void) close(2);
		(void) dup(1);

		/* arrange to get standard input */
		(void) close(mpvect[1]);
		(void) close(0);
		if (dup(mpvect[0]) < 0)
		{
			syserr("Cannot dup to zero!");
			_exit(EX_OSERR);
		}
		(void) close(mpvect[0]);
		if (!bitnset(M_RESTR, m->m_flags))
		{
			if (ctladdr == NULL || ctladdr->q_uid == 0)
			{
				(void) setgid(DefGid);
				(void) initgroups(DefUser, DefGid);
				(void) setuid(DefUid);
			}
			else
			{
				(void) setgid(ctladdr->q_gid);
				(void) initgroups(ctladdr->q_ruser ?
					ctladdr->q_ruser : ctladdr->q_user,
					ctladdr->q_gid);
				(void) setuid(ctladdr->q_uid);
			}
		}

		/* arrange for all the files to be closed */
		for (i = 3; i < DtableSize; i++)
#ifdef FIOCLEX
			(void) ioctl(i, FIOCLEX, 0);
#else FIOCLEX
			(void) close(i);
#endif FIOCLEX

		/* try to execute the mailer */
		execve(m->m_mailer, pvp, UserEnviron);

#ifdef FIOCLEX
		if (errno == ENOENT) {
			printf("554 Cannot exec %s\n", m->m_mailer);
			fflush(stdout);
			_exit(EX_UNAVAILABLE);
		}
		syserr("Cannot exec %s", m->m_mailer);
#else FIOCLEX
		printf("Cannot exec '%s' errno=%d\n", m->m_mailer, errno);
		(void) fflush(stdout);
#endif FIOCLEX
		if (m == LocalMailer || errno == EIO || errno == EAGAIN ||
		    errno == ENOMEM || errno == EPROCLIM)
			_exit(EX_TEMPFAIL);
		else
			_exit(EX_UNAVAILABLE);
	}

	/*
	**  Set up return value.
	*/

	(void) close(mpvect[0]);
	mfile = fdopen(mpvect[1], "w");
	if (clever)
	{
		(void) close(rpvect[1]);
		rfile = fdopen(rpvect[0], "r");
	}

	*pmfile = mfile;
	*prfile = rfile;

	return (pid);
}
/*
**  GIVERESPONSE -- Interpret an error response from a mailer
**
**	Parameters:
**		stat -- the status code from the mailer (high byte
**			only; core dumps must have been taken care of
**			already).
**		m -- the mailer descriptor for this mailer.
**
**	Returns:
**		none.
**
**	Side Effects:
**		Errors may be incremented.
**		ExitStat may be set.
*/

giveresponse(stat, m, e)
	int stat;
	register MAILER *m;
	ENVELOPE *e;
{
	register char *statmsg;
	extern char *SysExMsg[];
	register int i;
	extern int N_SysEx;
	char buf[MAXLINE];

#ifdef lint
	if (m == NULL)
		return;
#endif lint

	/*
	**  Compute status message from code.
	*/

	i = stat - EX__BASE;
	if (stat == 0)
		statmsg = "250 Sent";
	else if (i < 0 || i > N_SysEx)