srvrsmtp.c

早期freebsd实现

			if (p == NULL)
				break;
			a = parseaddr(p, NULLADDR, RF_COPYALL, ' ', NULL, e);
			if (a == NULL)
				break;
			a->q_flags |= QPRIMARY;
			a = recipient(a, &e->e_sendqueue, e);
			if (Errors != 0)
				break;

			/* no errors during parsing, but might be a duplicate */
			e->e_to = p;
			if (!bitset(QBADADDR, a->q_flags))
			{
				message("250 Recipient ok%s",
					bitset(QQUEUEUP, a->q_flags) ?
						" (will queue)" : "");
				nrcpts++;
			}
			else
			{
				/* punt -- should keep message in ADDRESS.... */
				message("550 Addressee unknown");
			}
			e->e_to = NULL;
			break;

		  case CMDDATA:		/* data -- text of mail */
			SmtpPhase = "server DATA";
			if (!gotmail)
			{
				message("503 Need MAIL command");
				break;
			}
			else if (nrcpts <= 0)
			{
				message("503 Need RCPT (recipient)");
				break;
			}

			/* check to see if we need to re-expand aliases */
			/* also reset QBADADDR on already-diagnosted addrs */
			doublequeue = FALSE;
			for (a = e->e_sendqueue; a != NULL; a = a->q_next)
			{
				if (bitset(QVERIFIED, a->q_flags))
				{
					/* need to re-expand aliases */
					doublequeue = TRUE;
				}
				if (bitset(QBADADDR, a->q_flags))
				{
					/* make this "go away" */
					a->q_flags |= QDONTSEND;
					a->q_flags &= ~QBADADDR;
				}
			}

			/* collect the text of the message */
			SmtpPhase = "collect";
			collect(TRUE, doublequeue, e);
			if (Errors != 0)
				goto abortmessage;
			HoldErrs = TRUE;

			/*
			**  Arrange to send to everyone.
			**	If sending to multiple people, mail back
			**		errors rather than reporting directly.
			**	In any case, don't mail back errors for
			**		anything that has happened up to
			**		now (the other end will do this).
			**	Truncate our transcript -- the mail has gotten
			**		to us successfully, and if we have
			**		to mail this back, it will be easier
			**		on the reader.
			**	Then send to everyone.
			**	Finally give a reply code.  If an error has
			**		already been given, don't mail a
			**		message back.
			**	We goose error returns by clearing error bit.
			*/

			SmtpPhase = "delivery";
			if (nrcpts != 1 && !doublequeue)
			{
				HoldErrs = TRUE;
				e->e_errormode = EM_MAIL;
			}
			e->e_xfp = freopen(queuename(e, 'x'), "w", e->e_xfp);
			id = e->e_id;

			/* send to all recipients */
			sendall(e, doublequeue ? SM_QUEUE : SM_DEFAULT);
			e->e_to = NULL;

			/* issue success if appropriate and reset */
			if (Errors == 0 || HoldErrs)
				message("250 %s Message accepted for delivery", id);

			if (bitset(EF_FATALERRS, e->e_flags) && !HoldErrs)
			{
				/* avoid sending back an extra message */
				e->e_flags &= ~EF_FATALERRS;
				e->e_flags |= EF_CLRQUEUE;
			}
			else
			{
				/* from now on, we have to operate silently */
				HoldErrs = TRUE;
				e->e_errormode = EM_MAIL;

				/* if we just queued, poke it */
				if (doublequeue && e->e_sendmode != SM_QUEUE)
				{
					extern pid_t dowork();

					unlockqueue(e);
					(void) dowork(id, TRUE, TRUE, e);
				}
			}

  abortmessage:
			/* if in a child, pop back to our parent */
			if (InChild)
				finis();

			/* clean up a bit */
			gotmail = FALSE;
			dropenvelope(e);
			CurEnv = e = newenvelope(e, CurEnv);
			e->e_flags = BlankEnvelope.e_flags;
			break;

		  case CMDRSET:		/* rset -- reset state */
			message("250 Reset state");
			e->e_flags |= EF_CLRQUEUE;
			if (InChild)
				finis();

			/* clean up a bit */
			gotmail = FALSE;
			dropenvelope(e);
			CurEnv = e = newenvelope(e, CurEnv);
			break;

		  case CMDVRFY:		/* vrfy -- verify address */
		  case CMDEXPN:		/* expn -- expand address */
			vrfy = c->cmdcode == CMDVRFY;
			if (bitset(vrfy ? PRIV_NOVRFY : PRIV_NOEXPN,
						PrivacyFlags))
			{
				if (vrfy)
					message("252 Who's to say?");
				else
					message("502 Sorry, we do not allow this operation");
#ifdef LOG
				if (LogLevel > 5)
					syslog(LOG_INFO, "%s: %s [rejected]",
						CurSmtpClient, inp);
#endif
				break;
			}
			else if (!gothello &&
				 bitset(vrfy ? PRIV_NEEDVRFYHELO : PRIV_NEEDEXPNHELO,
						PrivacyFlags))
			{
				message("503 I demand that you introduce yourself first");
				break;
			}
			if (runinchild(vrfy ? "SMTP-VRFY" : "SMTP-EXPN", e) > 0)
				break;
#ifdef LOG
			if (LogLevel > 5)
				syslog(LOG_INFO, "%s: %s", CurSmtpClient, inp);
#endif
			vrfyqueue = NULL;
			QuickAbort = TRUE;
			if (vrfy)
				e->e_flags |= EF_VRFYONLY;
			while (*p != '\0' && isascii(*p) && isspace(*p))
				*p++;
			if (*p == '\0')
			{
				message("501 Argument required");
				Errors++;
			}
			else
			{
				(void) sendtolist(p, NULLADDR, &vrfyqueue, e);
			}
			if (Errors != 0)
			{
				if (InChild)
					finis();
				break;
			}
			if (vrfyqueue == NULL)
			{
				message("554 Nothing to %s", vrfy ? "VRFY" : "EXPN");
			}
			while (vrfyqueue != NULL)
			{
				a = vrfyqueue;
				while ((a = a->q_next) != NULL &&
				       bitset(QDONTSEND|QBADADDR, a->q_flags))
					continue;
				if (!bitset(QDONTSEND|QBADADDR, vrfyqueue->q_flags))
					printvrfyaddr(vrfyqueue, a == NULL);
				vrfyqueue = vrfyqueue->q_next;
			}
			if (InChild)
				finis();
			break;

		  case CMDHELP:		/* help -- give user info */
			help(p);
			break;

		  case CMDNOOP:		/* noop -- do nothing */
			message("250 OK");
			break;

		  case CMDQUIT:		/* quit -- leave mail */
			message("221 %s closing connection", MyHostName);

doquit:
			/* avoid future 050 messages */
			disconnect(1, e);

			if (InChild)
				ExitStat = EX_QUIT;
			finis();

		  case CMDVERB:		/* set verbose mode */
			if (bitset(PRIV_NOEXPN, PrivacyFlags))
			{
				/* this would give out the same info */
				message("502 Verbose unavailable");
				break;
			}
			Verbose = TRUE;
			e->e_sendmode = SM_DELIVER;
			message("250 Verbose mode");
			break;

		  case CMDONEX:		/* doing one transaction only */
			OneXact = TRUE;
			message("250 Only one transaction");
			break;

# ifdef SMTPDEBUG
		  case CMDDBGQSHOW:	/* show queues */
			printf("Send Queue=");
			printaddr(e->e_sendqueue, TRUE);
			break;

		  case CMDDBGDEBUG:	/* set debug mode */
			tTsetup(tTdvect, sizeof tTdvect, "0-99.1");
			tTflag(p);
			message("200 Debug set");
			break;

# else /* not SMTPDEBUG */
		  case CMDDBGQSHOW:	/* show queues */
		  case CMDDBGDEBUG:	/* set debug mode */
# endif /* SMTPDEBUG */
		  case CMDLOGBOGUS:	/* bogus command */
# ifdef LOG
			if (LogLevel > 0)
				syslog(LOG_CRIT,
				    "\"%s\" command from %s (%s)",
				    c->cmdname, peerhostname,
				    anynet_ntoa(&RealHostAddr));
# endif
			/* FALL THROUGH */

		  case CMDERROR:	/* unknown command */
			if (++badcommands > MAXBADCOMMANDS)
			{
				message("421 %s Too many bad commands; closing connection",
					MyHostName);
				goto doquit;
			}

			message("500 Command unrecognized");
			break;

		  default:
			errno = 0;
			syserr("500 smtp: unknown code %d", c->cmdcode);
			break;
		}
	}
}
/*
**  SKIPWORD -- skip a fixed word.
**
**	Parameters:
**		p -- place to start looking.
**		w -- word to skip.
**
**	Returns:
**		p following w.
**		NULL on error.
**
**	Side Effects:
**		clobbers the p data area.
*/

static char *
skipword(p, w)
	register char *p;
	char *w;
{
	register char *q;
	char *firstp = p;

	/* find beginning of word */
	while (isascii(*p) && isspace(*p))
		p++;
	q = p;

	/* find end of word */
	while (*p != '\0' && *p != ':' && !(isascii(*p) && isspace(*p)))
		p++;
	while (isascii(*p) && isspace(*p))
		*p++ = '\0';
	if (*p != ':')
	{
	  syntax:
		message("501 Syntax error in parameters scanning \"%s\"",
			firstp);
		Errors++;
		return (NULL);
	}
	*p++ = '\0';
	while (isascii(*p) && isspace(*p))
		p++;

	if (*p == '\0')
		goto syntax;

	/* see if the input word matches desired word */
	if (strcasecmp(q, w))
		goto syntax;

	return (p);
}
/*
**  PRINTVRFYADDR -- print an entry in the verify queue
**
**	Parameters:
**		a -- the address to print
**		last -- set if this is the last one.
**
**	Returns:
**		none.
**
**	Side Effects:
**		Prints the appropriate 250 codes.
*/

printvrfyaddr(a, last)
	register ADDRESS *a;
	bool last;
{
	char fmtbuf[20];

	strcpy(fmtbuf, "250");
	fmtbuf[3] = last ? ' ' : '-';

	if (a->q_fullname == NULL)
	{
		if (strchr(a->q_user, '@') == NULL)
			strcpy(&fmtbuf[4], "<%s@%s>");
		else
			strcpy(&fmtbuf[4], "<%s>");
		message(fmtbuf, a->q_user, MyHostName);
	}
	else
	{
		if (strchr(a->q_user, '@') == NULL)
			strcpy(&fmtbuf[4], "%s <%s@%s>");
		else
			strcpy(&fmtbuf[4], "%s <%s>");
		message(fmtbuf, a->q_fullname, a->q_user, MyHostName);
	}
}
/*
**  HELP -- implement the HELP command.
**
**	Parameters:
**		topic -- the topic we want help for.
**
**	Returns:
**		none.
**
**	Side Effects:
**		outputs the help file to message output.
*/

help(topic)
	char *topic;
{
	register FILE *hf;
	int len;
	char buf[MAXLINE];
	bool noinfo;

	if (HelpFile == NULL || (hf = fopen(HelpFile, "r")) == NULL)
	{
		/* no help */
		errno = 0;
		message("502 HELP not implemented");
		return;
	}

	if (topic == NULL || *topic == '\0')
		topic = "smtp";
	else
		makelower(topic);

	len = strlen(topic);
	noinfo = TRUE;

	while (fgets(buf, sizeof buf, hf) != NULL)
	{
		if (strncmp(buf, topic, len) == 0)
		{
			register char *p;

			p = strchr(buf, '\t');
			if (p == NULL)
				p = buf;
			else
				p++;
			fixcrlf(p, TRUE);
			message("214-%s", p);
			noinfo = FALSE;
		}
	}

	if (noinfo)
		message("504 HELP topic unknown");
	else
		message("214 End of HELP info");
	(void) fclose(hf);
}
/*
**  RUNINCHILD -- return twice -- once in the child, then in the parent again
**
**	Parameters:
**		label -- a string used in error messages
**
**	Returns:
**		zero in the child
**		one in the parent
**
**	Side Effects:
**		none.
*/

runinchild(label, e)
	char *label;
	register ENVELOPE *e;
{
	int childpid;

	if (!OneXact)
	{
		childpid = dofork();
		if (childpid < 0)
		{
			syserr("%s: cannot fork", label);
			return (1);
		}
		if (childpid > 0)
		{
			auto int st;

			/* parent -- wait for child to complete */
			setproctitle("server %s child wait", CurHostName);
			st = waitfor(childpid);
			if (st == -1)
				syserr("%s: lost child", label);
			else if (!WIFEXITED(st))
				syserr("%s: died on signal %d",
					label, st & 0177);

			/* if we exited on a QUIT command, complete the process */
			if (WEXITSTATUS(st) == EX_QUIT)
			{
				disconnect(1, e);
				finis();
			}

			return (1);
		}
		else
		{
			/* child */
			InChild = TRUE;
			QuickAbort = FALSE;
			clearenvelope(e, FALSE);
		}
	}

	/* open alias database */
	initmaps(FALSE, e);

	return (0);
}

# endif /* SMTP */