usersmtp.c

早期freebsd实现

/*
 * Copyright (c) 1983 Eric P. Allman
 * Copyright (c) 1988, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

# include "sendmail.h"

#ifndef lint
#ifdef SMTP
static char sccsid[] = "@(#)usersmtp.c	8.18 (Berkeley) 1/24/94 (with SMTP)";
#else
static char sccsid[] = "@(#)usersmtp.c	8.18 (Berkeley) 1/24/94 (without SMTP)";
#endif
#endif /* not lint */

# include <sysexits.h>
# include <errno.h>

# ifdef SMTP

/*
**  USERSMTP -- run SMTP protocol from the user end.
**
**	This protocol is described in RFC821.
*/

#define REPLYTYPE(r)	((r) / 100)		/* first digit of reply code */
#define REPLYCLASS(r)	(((r) / 10) % 10)	/* second digit of reply code */
#define SMTPCLOSING	421			/* "Service Shutting Down" */

char	SmtpMsgBuffer[MAXLINE];		/* buffer for commands */
char	SmtpReplyBuffer[MAXLINE];	/* buffer for replies */
char	SmtpError[MAXLINE] = "";	/* save failure error messages */
int	SmtpPid;			/* pid of mailer */
bool	SmtpNeedIntro;			/* need "while talking" in transcript */

#ifdef __STDC__
extern	smtpmessage(char *f, MAILER *m, MCI *mci, ...);
#endif
/*
**  SMTPINIT -- initialize SMTP.
**
**	Opens the connection and sends the initial protocol.
**
**	Parameters:
**		m -- mailer to create connection to.
**		pvp -- pointer to parameter vector to pass to
**			the mailer.
**
**	Returns:
**		none.
**
**	Side Effects:
**		creates connection and sends initial protocol.
*/

smtpinit(m, mci, e)
	struct mailer *m;
	register MCI *mci;
	ENVELOPE *e;
{
	register int r;
	register char *p;
	extern void esmtp_check();
	extern void helo_options();

	if (tTd(18, 1))
	{
		printf("smtpinit ");
		mci_dump(mci, FALSE);
	}

	/*
	**  Open the connection to the mailer.
	*/

	SmtpError[0] = '\0';
	CurHostName = mci->mci_host;		/* XXX UGLY XXX */
	SmtpNeedIntro = TRUE;
	switch (mci->mci_state)
	{
	  case MCIS_ACTIVE:
		/* need to clear old information */
		smtprset(m, mci, e);
		/* fall through */

	  case MCIS_OPEN:
		return;

	  case MCIS_ERROR:
	  case MCIS_SSD:
		/* shouldn't happen */
		smtpquit(m, mci, e);
		/* fall through */

	  case MCIS_CLOSED:
		syserr("451 smtpinit: state CLOSED");
		return;

	  case MCIS_OPENING:
		break;
	}

	mci->mci_state = MCIS_OPENING;

	/*
	**  Get the greeting message.
	**	This should appear spontaneously.  Give it five minutes to
	**	happen.
	*/

	SmtpPhase = mci->mci_phase = "client greeting";
	setproctitle("%s %s: %s", e->e_id, CurHostName, mci->mci_phase);
	r = reply(m, mci, e, TimeOuts.to_initial, esmtp_check);
	if (r < 0 || REPLYTYPE(r) == 4)
		goto tempfail1;
	if (REPLYTYPE(r) != 2)
		goto unavailable;

	/*
	**  Send the HELO command.
	**	My mother taught me to always introduce myself.
	*/

	if (bitnset(M_ESMTP, m->m_flags))
		mci->mci_flags |= MCIF_ESMTP;

tryhelo:
	if (bitset(MCIF_ESMTP, mci->mci_flags))
	{
		smtpmessage("EHLO %s", m, mci, MyHostName);
		SmtpPhase = mci->mci_phase = "client EHLO";
	}
	else
	{
		smtpmessage("HELO %s", m, mci, MyHostName);
		SmtpPhase = mci->mci_phase = "client HELO";
	}
	setproctitle("%s %s: %s", e->e_id, CurHostName, mci->mci_phase);
	r = reply(m, mci, e, TimeOuts.to_helo, helo_options);
	if (r < 0)
		goto tempfail1;
	else if (REPLYTYPE(r) == 5)
	{
		if (bitset(MCIF_ESMTP, mci->mci_flags))
		{
			/* try old SMTP instead */
			mci->mci_flags &= ~MCIF_ESMTP;
			goto tryhelo;
		}
		goto unavailable;
	}
	else if (REPLYTYPE(r) != 2)
		goto tempfail1;

	/*
	**  Check to see if we actually ended up talking to ourself.
	**  This means we didn't know about an alias or MX, or we managed
	**  to connect to an echo server.
	**
	**	If this code remains at all, "CheckLoopBack" should be
	**	a mailer flag.  This is a MAYBENEXTRELEASE feature.
	*/

	p = strchr(&SmtpReplyBuffer[4], ' ');
	if (p != NULL)
		*p = '\0';
	if (CheckLoopBack && strcasecmp(&SmtpReplyBuffer[4], MyHostName) == 0)
	{
		syserr("553 %s config error: mail loops back to myself",
			MyHostName);
		mci->mci_exitstat = EX_CONFIG;
		mci->mci_errno = 0;
		smtpquit(m, mci, e);
		return;
	}

	/*
	**  If this is expected to be another sendmail, send some internal
	**  commands.
	*/

	if (bitnset(M_INTERNAL, m->m_flags))
	{
		/* tell it to be verbose */
		smtpmessage("VERB", m, mci);
		r = reply(m, mci, e, TimeOuts.to_miscshort, NULL);
		if (r < 0)
			goto tempfail2;
	}

	if (mci->mci_state != MCIS_CLOSED)
	{
		mci->mci_state = MCIS_OPEN;
		return;
	}

	/* got a 421 error code during startup */

  tempfail1:
  tempfail2:
	mci->mci_exitstat = EX_TEMPFAIL;
	if (mci->mci_errno == 0)
		mci->mci_errno = errno;
	if (mci->mci_state != MCIS_CLOSED)
		smtpquit(m, mci, e);
	return;

  unavailable:
	mci->mci_exitstat = EX_UNAVAILABLE;
	mci->mci_errno = errno;
	smtpquit(m, mci, e);
	return;
}
/*
**  ESMTP_CHECK -- check to see if this implementation likes ESMTP protocol
**
**
**	Parameters:
**		line -- the response line.
**		m -- the mailer.
**		mci -- the mailer connection info.
**		e -- the envelope.
**
**	Returns:
**		none.
*/

void
esmtp_check(line, m, mci, e)
	char *line;
	MAILER *m;
	register MCI *mci;
	ENVELOPE *e;
{
	if (strlen(line) < 5)
		return;
	line += 4;
	if (strncmp(line, "ESMTP ", 6) == 0)
		mci->mci_flags |= MCIF_ESMTP;
}
/*
**  HELO_OPTIONS -- process the options on a HELO line.
**
**	Parameters:
**		line -- the response line.
**		m -- the mailer.
**		mci -- the mailer connection info.
**		e -- the envelope.
**
**	Returns:
**		none.
*/

void
helo_options(line, m, mci, e)
	char *line;
	MAILER *m;
	register MCI *mci;
	ENVELOPE *e;
{
	register char *p;

	if (strlen(line) < 5)
		return;
	line += 4;
	p = strchr(line, ' ');
	if (p != NULL)
		*p++ = '\0';
	if (strcasecmp(line, "size") == 0)
	{
		mci->mci_flags |= MCIF_SIZE;
		if (p != NULL)
			mci->mci_maxsize = atol(p);
	}
	else if (strcasecmp(line, "8bitmime") == 0)
	{
		mci->mci_flags |= MCIF_8BITMIME;
		mci->mci_flags &= ~MCIF_7BIT;
	}
	else if (strcasecmp(line, "expn") == 0)
		mci->mci_flags |= MCIF_EXPN;
}
/*
**  SMTPMAILFROM -- send MAIL command
**
**	Parameters:
**		m -- the mailer.
**		mci -- the mailer connection structure.
**		e -- the envelope (including the sender to specify).
*/

smtpmailfrom(m, mci, e)
	struct mailer *m;
	MCI *mci;
	ENVELOPE *e;
{
	int r;
	char *bufp;
	char buf[MAXNAME];
	char optbuf[MAXLINE];

	if (tTd(18, 2))
		printf("smtpmailfrom: CurHost=%s\n", CurHostName);

	/* set up appropriate options to include */
	if (bitset(MCIF_SIZE, mci->mci_flags) && e->e_msgsize > 0)
		sprintf(optbuf, " SIZE=%ld", e->e_msgsize);
	else
		strcpy(optbuf, "");

	/*
	**  Send the MAIL command.
	**	Designates the sender.
	*/

	mci->mci_state = MCIS_ACTIVE;

	if (bitset(EF_RESPONSE, e->e_flags) &&
	    !bitnset(M_NO_NULL_FROM, m->m_flags))
		(void) strcpy(buf, "");
	else
		expand("\201g", buf, &buf[sizeof buf - 1], e);
	if (buf[0] == '<')
	{
		/* strip off <angle brackets> (put back on below) */
		bufp = &buf[strlen(buf) - 1];
		if (*bufp == '>')
			*bufp = '\0';
		bufp = &buf[1];
	}
	else
		bufp = buf;
	if (e->e_from.q_mailer == LocalMailer ||
	    !bitnset(M_FROMPATH, m->m_flags))
	{
		smtpmessage("MAIL From:<%s>%s", m, mci, bufp, optbuf);
	}
	else
	{
		smtpmessage("MAIL From:<@%s%c%s>%s", m, mci, MyHostName,
			*bufp == '@' ? ',' : ':', bufp, optbuf);
	}
	SmtpPhase = mci->mci_phase = "client MAIL";
	setproctitle("%s %s: %s", e->e_id, CurHostName, mci->mci_phase);
	r = reply(m, mci, e, TimeOuts.to_mail, NULL);
	if (r < 0 || REPLYTYPE(r) == 4)
	{
		mci->mci_exitstat = EX_TEMPFAIL;
		mci->mci_errno = errno;
		smtpquit(m, mci, e);
		return EX_TEMPFAIL;
	}
	else if (r == 250)
	{
		mci->mci_exitstat = EX_OK;
		return EX_OK;
	}
	else if (r == 552)
	{
		/* signal service unavailable */
		mci->mci_exitstat = EX_UNAVAILABLE;
		smtpquit(m, mci, e);
		return EX_UNAVAILABLE;
	}

#ifdef LOG
	if (LogLevel > 1)
	{
		syslog(LOG_CRIT, "%s: SMTP MAIL protocol error: %s",
			e->e_id, SmtpReplyBuffer);
	}
#endif

	/* protocol error -- close up */
	smtpquit(m, mci, e);
	mci->mci_exitstat = EX_PROTOCOL;
	return EX_PROTOCOL;
}
/*
**  SMTPRCPT -- designate recipient.
**
**	Parameters:
**		to -- address of recipient.
**		m -- the mailer we are sending to.
**		mci -- the connection info for this transaction.
**		e -- the envelope for this transaction.
**
**	Returns:
**		exit status corresponding to recipient status.
**
**	Side Effects:
**		Sends the mail via SMTP.
*/

smtprcpt(to, m, mci, e)
	ADDRESS *to;
	register MAILER *m;
	MCI *mci;
	ENVELOPE *e;
{
	register int r;

	smtpmessage("RCPT To:<%s>", m, mci, to->q_user);

	SmtpPhase = mci->mci_phase = "client RCPT";
	setproctitle("%s %s: %s", e->e_id, CurHostName, mci->mci_phase);
	r = reply(m, mci, e, TimeOuts.to_rcpt, NULL);
	if (r < 0 || REPLYTYPE(r) == 4)
		return (EX_TEMPFAIL);
	else if (REPLYTYPE(r) == 2)
		return (EX_OK);
	else if (r == 550 || r == 551 || r == 553)
		return (EX_NOUSER);
	else if (r == 552 || r == 554)
		return (EX_UNAVAILABLE);

#ifdef LOG
	if (LogLevel > 1)
	{
		syslog(LOG_CRIT, "%s: SMTP RCPT protocol error: %s",
			e->e_id, SmtpReplyBuffer);
	}
#endif