4.4BSD/usr/src/usr.sbin/sendmail/src/usersmtp.c
/*
* 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 8.1 (Berkeley) 6/7/93 (with SMTP)";
#else
static char sccsid[] = "@(#)usersmtp.c 8.1 (Berkeley) 6/7/93 (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 */
#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(17, 1))
{
printf("smtpinit ");
mci_dump(mci);
}
/*
** Open the connection to the mailer.
*/
SmtpError[0] = '\0';
CurHostName = mci->mci_host; /* XXX UGLY XXX */
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) != 2)
goto tempfail1;
/*
** 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.
*/
p = strchr(&SmtpReplyBuffer[4], ' ');
if (p != NULL)
*p = '\0';
if (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;
}
mci->mci_state = MCIS_OPEN;
return;
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;
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 buf[MAXNAME];
char optbuf[MAXLINE];
if (tTd(17, 2))
printf("smtpmailfrom: CurHost=%s\n", CurHostName);
/* set up appropriate options to include */
if (bitset(MCIF_SIZE, mci->mci_flags))
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 (e->e_from.q_mailer == LocalMailer ||
!bitnset(M_FROMPATH, m->m_flags))
{
smtpmessage("MAIL From:<%s>%s", m, mci, buf, optbuf);
}
else
{
smtpmessage("MAIL From:<@%s%c%s>%s", m, mci, MyHostName,
buf[0] == '@' ? ',' : ':', buf, 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
return (EX_PROTOCOL);
}
/*
** SMTPDATA -- send the data and clean up the transaction.
**
** Parameters:
** m -- mailer being sent to.
** e -- the envelope for this message.
**
** Returns:
** exit status corresponding to DATA command.
**
** Side Effects:
** none.
*/
smtpdata(m, mci, e)
struct mailer *m;
register MCI *mci;
register ENVELOPE *e;
{
register int r;
/*
** Send the data.
** First send the command and check that it is ok.
** Then send the data.
** Follow it up with a dot to terminate.
** Finally get the results of the transaction.
*/
/* send the command and check ok to proceed */
smtpmessage("DATA", m, mci);
SmtpPhase = mci->mci_phase = "client DATA 354";
setproctitle("%s %s: %s", e->e_id, CurHostName, mci->mci_phase);
r = reply(m, mci, e, TimeOuts.to_datainit, NULL);
if (r < 0 || REPLYTYPE(r) == 4)
{
smtpquit(m, mci, e);
return (EX_TEMPFAIL);
}
else if (r == 554)
{
smtprset(m, mci, e);
return (EX_UNAVAILABLE);
}
else if (r != 354)
{
#ifdef LOG
if (LogLevel > 1)
{
syslog(LOG_CRIT, "%s: SMTP DATA-1 protocol error: %s",
e->e_id, SmtpReplyBuffer);
}
#endif
smtprset(m, mci, e);
return (EX_PROTOCOL);
}
/* now output the actual message */
(*e->e_puthdr)(mci->mci_out, m, e);
putline("\n", mci->mci_out, m);
(*e->e_putbody)(mci->mci_out, m, e, NULL);
/* terminate the message */
fprintf(mci->mci_out, ".%s", m->m_eol);
if (Verbose)
nmessage(">>> .");
/* check for the results of the transaction */
SmtpPhase = mci->mci_phase = "client DATA 250";
setproctitle("%s %s: %s", e->e_id, CurHostName, mci->mci_phase);
r = reply(m, mci, e, TimeOuts.to_datafinal, NULL);
if (r < 0)
{
smtpquit(m, mci, e);
return (EX_TEMPFAIL);
}
mci->mci_state = MCIS_OPEN;
e->e_statmsg = newstr(&SmtpReplyBuffer[4]);
if (REPLYTYPE(r) == 4)
return (EX_TEMPFAIL);
else if (r == 250)
return (EX_OK);
else if (r == 552 || r == 554)
return (EX_UNAVAILABLE);
#ifdef LOG
if (LogLevel > 1)
{
syslog(LOG_CRIT, "%s: SMTP DATA-2 protocol error: %s",
e->e_id, SmtpReplyBuffer);
}
#endif
return (EX_PROTOCOL);
}
/*
** SMTPQUIT -- close the SMTP connection.
**
** Parameters:
** m -- a pointer to the mailer.
**
** Returns:
** none.
**
** Side Effects:
** sends the final protocol and closes the connection.
*/
smtpquit(m, mci, e)
register MAILER *m;
register MCI *mci;
ENVELOPE *e;
{
int i;
/* send the quit message if we haven't gotten I/O error */
if (mci->mci_state != MCIS_ERROR)
{
SmtpPhase = "client QUIT";
smtpmessage("QUIT", m, mci);
(void) reply(m, mci, e, TimeOuts.to_quit, NULL);
if (mci->mci_state == MCIS_CLOSED)
return;
}
/* now actually close the connection and pick up the zombie */
i = endmailer(mci, e, m->m_argv);
if (i != EX_OK)
syserr("451 smtpquit %s: stat %d", m->m_argv[0], i);
}
/*
** SMTPRSET -- send a RSET (reset) command
*/
smtprset(m, mci, e)
register MAILER *m;
register MCI *mci;
ENVELOPE *e;
{
int r;
SmtpPhase = "client RSET";
smtpmessage("RSET", m, mci);
r = reply(m, mci, e, TimeOuts.to_rset, NULL);
if (r < 0)
mci->mci_state = MCIS_ERROR;
else if (REPLYTYPE(r) == 2)
{
mci->mci_state = MCIS_OPEN;
return;
}
smtpquit(m, mci, e);
}
/*
** SMTPPROBE -- check the connection state
*/
smtpprobe(mci)
register MCI *mci;
{
int r;
MAILER *m = mci->mci_mailer;
extern ENVELOPE BlankEnvelope;
ENVELOPE *e = &BlankEnvelope;
SmtpPhase = "client probe";
smtpmessage("RSET", m, mci);
r = reply(m, mci, e, TimeOuts.to_miscshort, NULL);
if (r < 0 || REPLYTYPE(r) != 2)
smtpquit(m, mci, e);
return r;
}
/*
** REPLY -- read arpanet reply
**
** Parameters:
** m -- the mailer we are reading the reply from.
** mci -- the mailer connection info structure.
** e -- the current envelope.
** timeout -- the timeout for reads.
** pfunc -- processing function for second and subsequent
** lines of response -- if null, no special
** processing is done.
**
** Returns:
** reply code it reads.
**
** Side Effects:
** flushes the mail file.
*/
reply(m, mci, e, timeout, pfunc)
MAILER *m;
MCI *mci;
ENVELOPE *e;
time_t timeout;
void (*pfunc)();
{
register char *bufp;
register int r;
bool firstline = TRUE;
char junkbuf[MAXLINE];
if (mci->mci_out != NULL)
(void) fflush(mci->mci_out);
if (tTd(18, 1))
printf("reply\n");
/*
** Read the input line, being careful not to hang.
*/
for (bufp = SmtpReplyBuffer;; bufp = junkbuf)
{
register char *p;
extern time_t curtime();
/* actually do the read */
if (e->e_xfp != NULL)
(void) fflush(e->e_xfp); /* for debugging */
/* if we are in the process of closing just give the code */
if (mci->mci_state == MCIS_CLOSED)
return (SMTPCLOSING);
if (mci->mci_out != NULL)
fflush(mci->mci_out);
/* get the line from the other side */
p = sfgets(bufp, MAXLINE, mci->mci_in, timeout, SmtpPhase);
mci->mci_lastuse = curtime();
if (p == NULL)
{
extern char MsgBuf[]; /* err.c */
/* if the remote end closed early, fake an error */
if (errno == 0)
# ifdef ECONNRESET
errno = ECONNRESET;
# else /* ECONNRESET */
errno = EPIPE;
# endif /* ECONNRESET */
mci->mci_errno = errno;
mci->mci_exitstat = EX_TEMPFAIL;
message("451 %s: reply: read error from %s",
e->e_id == NULL ? "NOQUEUE" : e->e_id,
mci->mci_host);
/* if debugging, pause so we can see state */
if (tTd(18, 100))
pause();
# ifdef LOG
if (LogLevel > 1)
syslog(LOG_INFO, "%s", &MsgBuf[4]);
# endif /* LOG */
mci->mci_state = MCIS_ERROR;
smtpquit(m, mci, e);
return (-1);
}
fixcrlf(bufp, TRUE);
if (e->e_xfp != NULL && strchr("45", bufp[0]) != NULL)
{
/* serious error -- log the previous command */
if (SmtpMsgBuffer[0] != '\0')
fprintf(e->e_xfp, ">>> %s\n", SmtpMsgBuffer);
SmtpMsgBuffer[0] = '\0';
/* now log the message as from the other side */
fprintf(e->e_xfp, "<<< %s\n", bufp);
}
/* display the input for verbose mode */
if (Verbose)
nmessage("050 %s", bufp);
/* process the line */
if (pfunc != NULL && !firstline)
(*pfunc)(bufp, m, mci, e);
firstline = FALSE;
/* if continuation is required, we can go on */
if (bufp[3] == '-')
continue;
/* ignore improperly formated input */
if (!(isascii(bufp[0]) && isdigit(bufp[0])))
continue;
/* decode the reply code */
r = atoi(bufp);
/* extra semantics: 0xx codes are "informational" */
if (r >= 100)
break;
}
/*
** Now look at SmtpReplyBuffer -- only care about the first
** line of the response from here on out.
*/
/* save temporary failure messages for posterity */
if (SmtpReplyBuffer[0] == '4' && SmtpError[0] == '\0')
(void) strcpy(SmtpError, SmtpReplyBuffer);
/* reply code 421 is "Service Shutting Down" */
if (r == SMTPCLOSING && mci->mci_state != MCIS_SSD)
{
/* send the quit protocol */
mci->mci_state = MCIS_SSD;
smtpquit(m, mci, e);
}
return (r);
}
/*
** SMTPMESSAGE -- send message to server
**
** Parameters:
** f -- format
** m -- the mailer to control formatting.
** a, b, c -- parameters
**
** Returns:
** none.
**
** Side Effects:
** writes message to mci->mci_out.
*/
/*VARARGS1*/
#ifdef __STDC__
smtpmessage(char *f, MAILER *m, MCI *mci, ...)
#else
smtpmessage(f, m, mci, va_alist)
char *f;
MAILER *m;
MCI *mci;
va_dcl
#endif
{
VA_LOCAL_DECL
VA_START(mci);
(void) vsprintf(SmtpMsgBuffer, f, ap);
VA_END;
if (tTd(18, 1) || Verbose)
nmessage(">>> %s", SmtpMsgBuffer);
if (mci->mci_out != NULL)
{
fprintf(mci->mci_out, "%s%s", SmtpMsgBuffer,
m == NULL ? "\r\n" : m->m_eol);
}
else if (tTd(18, 1))
{
printf("smtpmessage: NULL mci_out\n");
}
}
# endif /* SMTP */