alias.c

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	FILE *af;
	bool nolock = FALSE;
	bool success = FALSE;
	long sff = SFF_OPENASROOT|SFF_REGONLY|SFF_NOLOCK;
	sigfunc_t oldsigint, oldsigquit;
#ifdef SIGTSTP
	sigfunc_t oldsigtstp;
#endif /* SIGTSTP */

	if (!bitset(MCF_REBUILDABLE, map->map_class->map_cflags))
		return FALSE;

	if (!bitnset(DBS_LINKEDALIASFILEINWRITABLEDIR, DontBlameSendmail))
		sff |= SFF_NOWLINK;
	if (!bitnset(DBS_GROUPWRITABLEALIASFILE, DontBlameSendmail))
		sff |= SFF_NOGWFILES;
	if (!bitnset(DBS_WORLDWRITABLEALIASFILE, DontBlameSendmail))
		sff |= SFF_NOWWFILES;

	/* try to lock the source file */
	if ((af = safefopen(map->map_file, O_RDWR, 0, sff)) == NULL)
	{
		struct stat stb;

		if ((errno != EACCES && errno != EROFS) || automatic ||
		    (af = safefopen(map->map_file, O_RDONLY, 0, sff)) == NULL)
		{
			int saveerr = errno;

			if (tTd(27, 1))
				dprintf("Can't open %s: %s\n",
					map->map_file, errstring(saveerr));
			if (!automatic && !bitset(MF_OPTIONAL, map->map_mflags))
				message("newaliases: cannot open %s: %s",
					map->map_file, errstring(saveerr));
			errno = 0;
			return FALSE;
		}
		nolock = TRUE;
		if (tTd(27, 1) ||
		    fstat(fileno(af), &stb) < 0 ||
		    bitset(S_IWUSR|S_IWGRP|S_IWOTH, stb.st_mode))
			message("warning: cannot lock %s: %s",
				map->map_file, errstring(errno));
	}

	/* see if someone else is rebuilding the alias file */
	if (!nolock &&
	    !lockfile(fileno(af), map->map_file, NULL, LOCK_EX|LOCK_NB))
	{
		/* yes, they are -- wait until done */
		message("Alias file %s is locked (maybe being rebuilt)",
			map->map_file);
		if (OpMode != MD_INITALIAS)
		{
			/* wait for other rebuild to complete */
			(void) lockfile(fileno(af), map->map_file, NULL,
					LOCK_EX);
		}
		(void) fclose(af);
		errno = 0;
		return FALSE;
	}

	oldsigint = setsignal(SIGINT, SIG_IGN);
	oldsigquit = setsignal(SIGQUIT, SIG_IGN);
#ifdef SIGTSTP
	oldsigtstp = setsignal(SIGTSTP, SIG_IGN);
#endif /* SIGTSTP */

	if (map->map_class->map_open(map, O_RDWR))
	{
		if (LogLevel > 7)
		{
			sm_syslog(LOG_NOTICE, NOQID,
				"alias database %s %srebuilt by %s",
				map->map_file, automatic ? "auto" : "",
				username());
		}
		map->map_mflags |= MF_OPEN|MF_WRITABLE;
		map->map_pid = getpid();
		readaliases(map, af, !automatic, TRUE);
		success = TRUE;
	}
	else
	{
		if (tTd(27, 1))
			dprintf("Can't create database for %s: %s\n",
				map->map_file, errstring(errno));
		if (!automatic)
			syserr("Cannot create database for alias file %s",
				map->map_file);
	}

	/* close the file, thus releasing locks */
	(void) fclose(af);

	/* add distinguished entries and close the database */
	if (bitset(MF_OPEN, map->map_mflags))
	{
		map->map_class->map_close(map);
		map->map_mflags &= ~(MF_OPEN|MF_WRITABLE);
	}

	/* restore the old signals */
	(void) setsignal(SIGINT, oldsigint);
	(void) setsignal(SIGQUIT, oldsigquit);
# ifdef SIGTSTP
	(void) setsignal(SIGTSTP, oldsigtstp);
# endif /* SIGTSTP */
	return success;
}
/*
**  READALIASES -- read and process the alias file.
**
**	This routine implements the part of initaliases that occurs
**	when we are not going to use the DBM stuff.
**
**	Parameters:
**		map -- the alias database descriptor.
**		af -- file to read the aliases from.
**		announcestats -- announce statistics regarding number of
**			aliases, longest alias, etc.
**		logstats -- lot the same info.
**
**	Returns:
**		none.
**
**	Side Effects:
**		Reads aliasfile into the symbol table.
**		Optionally, builds the .dir & .pag files.
*/

void
readaliases(map, af, announcestats, logstats)
	register MAP *map;
	FILE *af;
	bool announcestats;
	bool logstats;
{
	register char *p;
	char *rhs;
	bool skipping;
	long naliases, bytes, longest;
	ADDRESS al, bl;
	char line[BUFSIZ];

	/*
	**  Read and interpret lines
	*/

	FileName = map->map_file;
	LineNumber = 0;
	naliases = bytes = longest = 0;
	skipping = FALSE;
	while (fgets(line, sizeof line, af) != NULL)
	{
		int lhssize, rhssize;
		int c;

		LineNumber++;
		p = strchr(line, '\n');
		while (p != NULL && p > line && p[-1] == '\\')
		{
			p--;
			if (fgets(p, SPACELEFT(line, p), af) == NULL)
				break;
			LineNumber++;
			p = strchr(p, '\n');
		}
		if (p != NULL)
			*p = '\0';
		else if (!feof(af))
		{
			errno = 0;
			syserr("554 5.3.0 alias line too long");

			/* flush to end of line */
			while ((c = getc(af)) != EOF && c != '\n')
				continue;

			/* skip any continuation lines */
			skipping = TRUE;
			continue;
		}
		switch (line[0])
		{
		  case '#':
		  case '\0':
			skipping = FALSE;
			continue;

		  case ' ':
		  case '\t':
			if (!skipping)
				syserr("554 5.3.5 Non-continuation line starts with space");
			skipping = TRUE;
			continue;
		}
		skipping = FALSE;

		/*
		**  Process the LHS
		**	Find the colon separator, and parse the address.
		**	It should resolve to a local name -- this will
		**	be checked later (we want to optionally do
		**	parsing of the RHS first to maximize error
		**	detection).
		*/

		for (p = line; *p != '\0' && *p != ':' && *p != '\n'; p++)
			continue;
		if (*p++ != ':')
		{
			syserr("554 5.3.5 missing colon");
			continue;
		}
		if (parseaddr(line, &al, RF_COPYALL, ':', NULL, CurEnv) == NULL)
		{
			syserr("554 5.3.5 %.40s... illegal alias name", line);
			continue;
		}

		/*
		**  Process the RHS.
		**	'al' is the internal form of the LHS address.
		**	'p' points to the text of the RHS.
		*/

		while (isascii(*p) && isspace(*p))
			p++;
		rhs = p;
		for (;;)
		{
			register char *nlp;

			nlp = &p[strlen(p)];
			if (nlp[-1] == '\n')
				*--nlp = '\0';

			if (CheckAliases)
			{
				/* do parsing & compression of addresses */
				while (*p != '\0')
				{
					auto char *delimptr;

					while ((isascii(*p) && isspace(*p)) ||
								*p == ',')
						p++;
					if (*p == '\0')
						break;
					if (parseaddr(p, &bl, RF_COPYNONE, ',',
						      &delimptr, CurEnv) == NULL)
						usrerr("553 5.3.5 %s... bad address", p);
					p = delimptr;
				}
			}
			else
			{
				p = nlp;
			}

			/* see if there should be a continuation line */
			c = getc(af);
			if (!feof(af))
				(void) ungetc(c, af);
			if (c != ' ' && c != '\t')
				break;

			/* read continuation line */
			if (fgets(p, sizeof line - (p - line), af) == NULL)
				break;
			LineNumber++;

			/* check for line overflow */
			if (strchr(p, '\n') == NULL && !feof(af))
			{
				usrerr("554 5.3.5 alias too long");
				while ((c = fgetc(af)) != EOF && c != '\n')
					continue;
				skipping = TRUE;
				break;
			}
		}

		if (skipping)
			continue;

		if (!bitnset(M_ALIASABLE, al.q_mailer->m_flags))
		{
			syserr("554 5.3.5 %s... cannot alias non-local names",
				al.q_paddr);
			continue;
		}

		/*
		**  Insert alias into symbol table or database file.
		**
		**	Special case pOStmaStER -- always make it lower case.
		*/

		if (strcasecmp(al.q_user, "postmaster") == 0)
			makelower(al.q_user);

		lhssize = strlen(al.q_user);
		rhssize = strlen(rhs);
		if (rhssize > 0)
		{
			/* is RHS empty (just spaces)? */
			p = rhs;
			while (isascii(*p) && isspace(*p))
				p++;
		}
		if (rhssize == 0 || *p == '\0')
		{
			syserr("554 5.3.5 %.40s... missing value for alias",
			       line);

		}
		else
		{
			map->map_class->map_store(map, al.q_user, rhs);

			/* statistics */
			naliases++;
			bytes += lhssize + rhssize;
			if (rhssize > longest)
				longest = rhssize;
		}

		if (al.q_paddr != NULL)
			free(al.q_paddr);
		if (al.q_host != NULL)
			free(al.q_host);
		if (al.q_user != NULL)
			free(al.q_user);
	}

	CurEnv->e_to = NULL;
	FileName = NULL;
	if (Verbose || announcestats)
		message("%s: %ld aliases, longest %ld bytes, %ld bytes total",
			map->map_file, naliases, longest, bytes);
	if (LogLevel > 7 && logstats)
		sm_syslog(LOG_INFO, NOQID,
			"%s: %ld aliases, longest %ld bytes, %ld bytes total",
			map->map_file, naliases, longest, bytes);
}
/*
**  FORWARD -- Try to forward mail
**
**	This is similar but not identical to aliasing.
**
**	Parameters:
**		user -- the name of the user who's mail we would like
**			to forward to.  It must have been verified --
**			i.e., the q_home field must have been filled
**			in.
**		sendq -- a pointer to the head of the send queue to
**			put this user's aliases in.
**		aliaslevel -- the current alias nesting depth.
**		e -- the current envelope.
**
**	Returns:
**		none.
**
**	Side Effects:
**		New names are added to send queues.
*/

void
forward(user, sendq, aliaslevel, e)
	ADDRESS *user;
	ADDRESS **sendq;
	int aliaslevel;
	register ENVELOPE *e;
{
	char *pp;
	char *ep;
	bool got_transient;

	if (tTd(27, 1))
		dprintf("forward(%s)\n", user->q_paddr);

	if (!bitnset(M_HASPWENT, user->q_mailer->m_flags) ||
	    !QS_IS_OK(user->q_state))
		return;
	if (user->q_home == NULL)
	{
		syserr("554 5.3.0 forward: no home");
		user->q_home = "/no/such/directory";
	}

	/* good address -- look for .forward file in home */
	define('z', user->q_home, e);
	define('u', user->q_user, e);
	define('h', user->q_host, e);
	if (ForwardPath == NULL)
		ForwardPath = newstr("\201z/.forward");

	got_transient = FALSE;
	for (pp = ForwardPath; pp != NULL; pp = ep)
	{
		int err;
		char buf[MAXPATHLEN + 1];
		struct stat st;

		ep = strchr(pp, SEPARATOR);
		if (ep != NULL)
			*ep = '\0';
		expand(pp, buf, sizeof buf, e);
		if (ep != NULL)
			*ep++ = SEPARATOR;
		if (buf[0] == '\0')
			continue;
		if (tTd(27, 3))
			dprintf("forward: trying %s\n", buf);

		err = include(buf, TRUE, user, sendq, aliaslevel, e);
		if (err == 0)
			break;
		else if (transienterror(err))
		{
			/* we may have to suspend this message */
			got_transient = TRUE;
			if (tTd(27, 2))
				dprintf("forward: transient error on %s\n",
					buf);
			if (LogLevel > 2)
			{
				char *curhost = CurHostName;

				CurHostName = NULL;
				sm_syslog(LOG_ERR, e->e_id,
					  "forward %s: transient error: %s",
					  buf, errstring(err));
				CurHostName = curhost;
			}

		}
		else
		{
			switch (err)
			{
			  case ENOENT:
				break;

			  case E_SM_WWDIR:
			  case E_SM_GWDIR:
				/* check if it even exists */
				if (stat(buf, &st) < 0 && errno == ENOENT)
				{
					if (bitnset(DBS_DONTWARNFORWARDFILEINUNSAFEDIRPATH,
						    DontBlameSendmail))
						break;
				}
				/* FALLTHROUGH */

#if _FFR_FORWARD_SYSERR
			  case E_SM_NOSLINK:
			  case E_SM_NOHLINK:
			  case E_SM_REGONLY:
			  case E_SM_ISEXEC:
			  case E_SM_WWFILE:
			  case E_SM_GWFILE:
				syserr("forward: %s: %s", buf, errstring(err));
				break;
#endif /* _FFR_FORWARD_SYSERR */

			  default:
				if (LogLevel > (RunAsUid == 0 ? 2 : 10))
					sm_syslog(LOG_WARNING, e->e_id,
						"forward %s: %s", buf,
						errstring(err));
				if (Verbose)
					message("forward: %s: %s",
						buf,
						errstring(err));
				break;
			}
		}
	}
	if (pp == NULL && got_transient)
	{
		/*
		**  There was no successful .forward open and at least one
		**  transient open.  We have to defer this address for
		**  further delivery.
		*/

		message("transient .forward open error: message queued");
		user->q_state = QS_QUEUEUP;
		return;
	}
}