Example #1
0
void    cleanup_post_jail(char *unused_name, char **unused_argv)
{

    /*
     * Optionally set the file size resource limit. XXX This limits the
     * message content to somewhat less than requested, because the total
     * queue file size also includes envelope information. Unless people set
     * really low limit, the difference is going to matter only when a queue
     * file has lots of recipients.
     */
    if (var_message_limit > 0)
	set_file_limit((off_t) var_message_limit);

    /*
     * Control how unmatched extensions are propagated.
     */
    cleanup_ext_prop_mask =
	ext_prop_mask(VAR_PROP_EXTENSION, var_prop_extension);

    /*
     * Setup the filters for characters that should be rejected, and for
     * characters that should be removed.
     */
    if (*var_msg_reject_chars) {
	cleanup_reject_chars = vstring_alloc(strlen(var_msg_reject_chars));
	unescape(cleanup_reject_chars, var_msg_reject_chars);
    }
    if (*var_msg_strip_chars) {
	cleanup_strip_chars = vstring_alloc(strlen(var_msg_strip_chars));
	unescape(cleanup_strip_chars, var_msg_strip_chars);
    }
}
Example #2
0
static void pre_init(char *unused_name, char **unused_argv)
{

    /*
     * Reset the file size limit from the message size limit to the mailbox
     * size limit. XXX This still isn't accurate because the file size limit
     * also affects delivery to command.
     * 
     * A file size limit protects the machine against runaway software errors.
     * It is not suitable to enforce mail quota, because users can get around
     * mail quota by delivering to /file/name or to |command.
     * 
     * We can't have mailbox size limit smaller than the message size limit,
     * because that prohibits the delivery agent from updating the queue
     * file.
     */
    if (var_mailbox_limit) {
	if (var_mailbox_limit < var_message_limit || var_message_limit == 0)
	    msg_fatal("main.cf configuration error: %s is smaller than %s",
		      VAR_MAILBOX_LIMIT, VAR_MESSAGE_LIMIT);
	set_file_limit(var_mailbox_limit);
    }
    alias_maps = maps_create("aliases", var_alias_maps,
			     DICT_FLAG_LOCK | DICT_FLAG_PARANOID
			     | DICT_FLAG_FOLD_FIX);

    flush_init();
}
Example #3
0
static int init_process(void)
{
    if (settings.process.file_limit) {
        if (set_file_limit(settings.process.file_limit) < 0) {
            return -__LINE__;
        }
    }
    if (settings.process.core_limit) {
        if (set_core_limit(settings.process.core_limit) < 0) {
            return -__LINE__;
        }
    }

    return 0;
}
Example #4
0
static void pre_init(char *unused_name, char **unused_argv)
{

    /*
     * Reset the file size limit from the message size limit to the mailbox
     * size limit.
     * 
     * We can't have mailbox size limit smaller than the message size limit,
     * because that prohibits the delivery agent from updating the queue
     * file.
     */
    if (var_virt_mailbox_limit) {
	if (var_virt_mailbox_limit < var_message_limit || var_message_limit == 0)
	    msg_fatal("main.cf configuration error: %s is smaller than %s",
		      VAR_VIRT_MAILBOX_LIMIT, VAR_MESSAGE_LIMIT);
	set_file_limit(var_virt_mailbox_limit);
    }

    /*
     * flush client.
     */
    flush_init();
}
Example #5
0
int     main(int argc, char **argv)
{
    static VSTREAM *lock_fp;
    static VSTREAM *data_lock_fp;
    VSTRING *lock_path;
    VSTRING *data_lock_path;
    off_t   inherited_limit;
    int     debug_me = 0;
    int     ch;
    int     fd;
    int     n;
    int     test_lock = 0;
    VSTRING *why;
    WATCHDOG *watchdog;
    ARGV   *import_env;

    /*
     * Fingerprint executables and core dumps.
     */
    MAIL_VERSION_STAMP_ALLOCATE;

    /*
     * Initialize.
     */
    umask(077);					/* never fails! */

    /*
     * Process environment options as early as we can.
     */
    if (getenv(CONF_ENV_VERB))
	msg_verbose = 1;
    if (getenv(CONF_ENV_DEBUG))
	debug_me = 1;

    /*
     * Don't die when a process goes away unexpectedly.
     */
    signal(SIGPIPE, SIG_IGN);

    /*
     * Strip and save the process name for diagnostics etc.
     */
    var_procname = mystrdup(basename(argv[0]));

    /*
     * When running a child process, don't leak any open files that were
     * leaked to us by our own (privileged) parent process. Descriptors 0-2
     * are taken care of after we have initialized error logging.
     * 
     * Some systems such as AIX have a huge per-process open file limit. In
     * those cases, limit the search for potential file descriptor leaks to
     * just the first couple hundred.
     * 
     * The Debian post-installation script passes an open file descriptor into
     * the master process and waits forever for someone to close it. Because
     * of this we have to close descriptors > 2, and pray that doing so does
     * not break things.
     */
    closefrom(3);

    /*
     * Initialize logging and exit handler.
     */
    msg_syslog_init(mail_task(var_procname), LOG_PID, LOG_FACILITY);

    /*
     * Check the Postfix library version as soon as we enable logging.
     */
    MAIL_VERSION_CHECK;

    /*
     * The mail system must be run by the superuser so it can revoke
     * privileges for selected operations. That's right - it takes privileges
     * to toss privileges.
     */
    if (getuid() != 0)
	msg_fatal("the master command is reserved for the superuser");
    if (unsafe() != 0)
	msg_fatal("the master command must not run as a set-uid process");

    /*
     * Process JCL.
     */
    while ((ch = GETOPT(argc, argv, "c:Dde:tv")) > 0) {
	switch (ch) {
	case 'c':
	    if (setenv(CONF_ENV_PATH, optarg, 1) < 0)
		msg_fatal("out of memory");
	    break;
	case 'd':
	    master_detach = 0;
	    break;
	case 'e':
	    event_request_timer(master_exit_event, (char *) 0, atoi(optarg));
	    break;
	case 'D':
	    debug_me = 1;
	    break;
	case 't':
	    test_lock = 1;
	    break;
	case 'v':
	    msg_verbose++;
	    break;
	default:
	    usage(argv[0]);
	    /* NOTREACHED */
	}
    }

    /*
     * This program takes no other arguments.
     */
    if (argc > optind)
	usage(argv[0]);

    /*
     * If started from a terminal, get rid of any tty association. This also
     * means that all errors and warnings must go to the syslog daemon.
     */
    if (master_detach)
	for (fd = 0; fd < 3; fd++) {
	    (void) close(fd);
	    if (open("/dev/null", O_RDWR, 0) != fd)
		msg_fatal("open /dev/null: %m");
	}

    /*
     * Run in a separate process group, so that "postfix stop" can terminate
     * all MTA processes cleanly. Give up if we can't separate from our
     * parent process. We're not supposed to blow away the parent.
     */
    if (debug_me == 0 && master_detach != 0 && setsid() == -1 && getsid(0) != getpid())
	msg_fatal("unable to set session and process group ID: %m");

    /*
     * Make some room for plumbing with file descriptors. XXX This breaks
     * when a service listens on many ports. In order to do this right we
     * must change the master-child interface so that descriptors do not need
     * to have fixed numbers.
     * 
     * In a child we need two descriptors for the flow control pipe, one for
     * child->master status updates and at least one for listening.
     */
    for (n = 0; n < 5; n++) {
	if (close_on_exec(dup(0), CLOSE_ON_EXEC) < 0)
	    msg_fatal("dup(0): %m");
    }

    /*
     * Final initializations. Unfortunately, we must read the global Postfix
     * configuration file after doing command-line processing, so that we get
     * consistent results when we SIGHUP the server to reload configuration
     * files.
     */
    master_vars_init();

    /*
     * In case of multi-protocol support. This needs to be done because
     * master does not invoke mail_params_init() (it was written before that
     * code existed).
     */
    (void) inet_proto_init(VAR_INET_PROTOCOLS, var_inet_protocols);

    /*
     * Environment import filter, to enforce consistent behavior whether
     * Postfix is started by hand, or at system boot time.
     */
    import_env = argv_split(var_import_environ, ", \t\r\n");
    clean_env(import_env->argv);
    argv_free(import_env);

    if ((inherited_limit = get_file_limit()) < 0)
	set_file_limit(OFF_T_MAX);

    if (chdir(var_queue_dir))
	msg_fatal("chdir %s: %m", var_queue_dir);

    /*
     * Lock down the master.pid file. In test mode, no file means that it
     * isn't locked.
     */
    lock_path = vstring_alloc(10);
    data_lock_path = vstring_alloc(10);
    why = vstring_alloc(10);

    vstring_sprintf(lock_path, "%s/%s.pid", DEF_PID_DIR, var_procname);
    if (test_lock && access(vstring_str(lock_path), F_OK) < 0)
	exit(0);
    lock_fp = open_lock(vstring_str(lock_path), O_RDWR | O_CREAT, 0644, why);
    if (test_lock)
	exit(lock_fp ? 0 : 1);
    if (lock_fp == 0)
	msg_fatal("open lock file %s: %s",
		  vstring_str(lock_path), vstring_str(why));
    vstream_fprintf(lock_fp, "%*lu\n", (int) sizeof(unsigned long) * 4,
		    (unsigned long) var_pid);
    if (vstream_fflush(lock_fp))
	msg_fatal("cannot update lock file %s: %m", vstring_str(lock_path));
    close_on_exec(vstream_fileno(lock_fp), CLOSE_ON_EXEC);

    /*
     * Lock down the Postfix-writable data directory.
     */
    vstring_sprintf(data_lock_path, "%s/%s.lock", var_data_dir, var_procname);
    set_eugid(var_owner_uid, var_owner_gid);
    data_lock_fp =
	open_lock(vstring_str(data_lock_path), O_RDWR | O_CREAT, 0644, why);
    set_ugid(getuid(), getgid());
    if (data_lock_fp == 0)
	msg_fatal("open lock file %s: %s",
		  vstring_str(data_lock_path), vstring_str(why));
    vstream_fprintf(data_lock_fp, "%*lu\n", (int) sizeof(unsigned long) * 4,
		    (unsigned long) var_pid);
    if (vstream_fflush(data_lock_fp))
	msg_fatal("cannot update lock file %s: %m", vstring_str(data_lock_path));
    close_on_exec(vstream_fileno(data_lock_fp), CLOSE_ON_EXEC);

    /*
     * Clean up.
     */
    vstring_free(why);
    vstring_free(lock_path);
    vstring_free(data_lock_path);

    /*
     * Optionally start the debugger on ourself.
     */
    if (debug_me)
	debug_process();

    /*
     * Finish initialization, last part. We must process configuration files
     * after processing command-line parameters, so that we get consistent
     * results when we SIGHUP the server to reload configuration files.
     */
    master_config();
    master_sigsetup();
    master_flow_init();
    msg_info("daemon started -- version %s, configuration %s",
	     var_mail_version, var_config_dir);

    /*
     * Process events. The event handler will execute the read/write/timer
     * action routines. Whenever something has happened, see if we received
     * any signal in the mean time. Although the master process appears to do
     * multiple things at the same time, it really is all a single thread, so
     * that there are no concurrency conflicts within the master process.
     */
#define MASTER_WATCHDOG_TIME	1000

    watchdog = watchdog_create(MASTER_WATCHDOG_TIME, (WATCHDOG_FN) 0, (char *) 0);
    for (;;) {
#ifdef HAS_VOLATILE_LOCKS
	if (myflock(vstream_fileno(lock_fp), INTERNAL_LOCK,
		    MYFLOCK_OP_EXCLUSIVE) < 0)
	    msg_fatal("refresh exclusive lock: %m");
	if (myflock(vstream_fileno(data_lock_fp), INTERNAL_LOCK,
		    MYFLOCK_OP_EXCLUSIVE) < 0)
	    msg_fatal("refresh exclusive lock: %m");
#endif
	watchdog_start(watchdog);		/* same as trigger servers */
	event_loop(MASTER_WATCHDOG_TIME / 2);
	if (master_gotsighup) {
	    msg_info("reload -- version %s, configuration %s",
		     var_mail_version, var_config_dir);
	    master_gotsighup = 0;		/* this first */
	    master_vars_init();			/* then this */
	    master_refresh();			/* then this */
	}
	if (master_gotsigchld) {
	    if (msg_verbose)
		msg_info("got sigchld");
	    master_gotsigchld = 0;		/* this first */
	    master_reap_child();		/* then this */
	}
    }
}
Example #6
0
static void enqueue(const int flags, const char *encoding,
		         const char *dsn_envid, int dsn_ret, int dsn_notify,
		            const char *rewrite_context, const char *sender,
		            const char *full_name, char **recipients)
{
    VSTRING *buf;
    VSTREAM *dst;
    char   *saved_sender;
    char  **cpp;
    int     type;
    char   *start;
    int     skip_from_;
    TOK822 *tree;
    TOK822 *tp;
    int     rcpt_count = 0;
    enum {
	STRIP_CR_DUNNO, STRIP_CR_DO, STRIP_CR_DONT, STRIP_CR_ERROR
    }       strip_cr;
    MAIL_STREAM *handle;
    VSTRING *postdrop_command;
    uid_t   uid = getuid();
    int     status;
    int     naddr;
    int     prev_type;
    MIME_STATE *mime_state = 0;
    SM_STATE state;
    int     mime_errs;
    const char *errstr;
    int     addr_count;
    int     level;
    static NAME_CODE sm_fix_eol_table[] = {
	SM_FIX_EOL_ALWAYS, STRIP_CR_DO,
	SM_FIX_EOL_STRICT, STRIP_CR_DUNNO,
	SM_FIX_EOL_NEVER, STRIP_CR_DONT,
	0, STRIP_CR_ERROR,
    };

    /*
     * Access control is enforced in the postdrop command. The code here
     * merely produces a more user-friendly interface.
     */
    if ((errstr = check_user_acl_byuid(VAR_SUBMIT_ACL,
				       var_submit_acl, uid)) != 0)
	msg_fatal_status(EX_NOPERM,
	  "User %s(%ld) is not allowed to submit mail", errstr, (long) uid);

    /*
     * Initialize.
     */
    buf = vstring_alloc(100);

    /*
     * Stop run-away process accidents by limiting the queue file size. This
     * is not a defense against DOS attack.
     */
    if (var_message_limit > 0 && get_file_limit() > var_message_limit)
	set_file_limit((off_t) var_message_limit);

    /*
     * The sender name is provided by the user. In principle, the mail pickup
     * service could deduce the sender name from queue file ownership, but:
     * pickup would not be able to run chrooted, and it may not be desirable
     * to use login names at all.
     */
    if (sender != 0) {
	VSTRING_RESET(buf);
	VSTRING_TERMINATE(buf);
	tree = tok822_parse(sender);
	for (naddr = 0, tp = tree; tp != 0; tp = tp->next)
	    if (tp->type == TOK822_ADDR && naddr++ == 0)
		tok822_internalize(buf, tp->head, TOK822_STR_DEFL);
	tok822_free_tree(tree);
	saved_sender = mystrdup(STR(buf));
	if (naddr > 1)
	    msg_warn("-f option specified malformed sender: %s", sender);
    } else {
	if ((sender = username()) == 0)
	    msg_fatal_status(EX_OSERR, "no login name found for user ID %lu",
			     (unsigned long) uid);
	saved_sender = mystrdup(sender);
    }

    /*
     * Let the postdrop command open the queue file for us, and sanity check
     * the content. XXX Make postdrop a manifest constant.
     */
    errno = 0;
    postdrop_command = vstring_alloc(1000);
    vstring_sprintf(postdrop_command, "%s/postdrop -r", var_command_dir);
    for (level = 0; level < msg_verbose; level++)
	vstring_strcat(postdrop_command, " -v");
    if ((handle = mail_stream_command(STR(postdrop_command))) == 0)
	msg_fatal_status(EX_UNAVAILABLE, "%s(%ld): unable to execute %s: %m",
			 saved_sender, (long) uid, STR(postdrop_command));
    vstring_free(postdrop_command);
    dst = handle->stream;

    /*
     * First, write envelope information to the output stream.
     * 
     * For sendmail compatibility, parse each command-line recipient as if it
     * were an RFC 822 message header; some MUAs specify comma-separated
     * recipient lists; and some MUAs even specify "word word <address>".
     * 
     * Sort-uniq-ing the recipient list is done after address canonicalization,
     * before recipients are written to queue file. That's cleaner than
     * having the queue manager nuke duplicate recipient status records.
     * 
     * XXX Should limit the size of envelope records.
     * 
     * With "sendmail -N", instead of a per-message NOTIFY record we store one
     * per recipient so that we can simplify the implementation somewhat.
     */
    if (dsn_envid)
	rec_fprintf(dst, REC_TYPE_ATTR, "%s=%s",
		    MAIL_ATTR_DSN_ENVID, dsn_envid);
    if (dsn_ret)
	rec_fprintf(dst, REC_TYPE_ATTR, "%s=%d",
		    MAIL_ATTR_DSN_RET, dsn_ret);
    rec_fprintf(dst, REC_TYPE_ATTR, "%s=%s",
		MAIL_ATTR_RWR_CONTEXT, rewrite_context);
    if (full_name || (full_name = fullname()) != 0)
	rec_fputs(dst, REC_TYPE_FULL, full_name);
    rec_fputs(dst, REC_TYPE_FROM, saved_sender);
    if (verp_delims && *saved_sender == 0)
	msg_fatal_status(EX_USAGE,
		      "%s(%ld): -V option requires non-null sender address",
			 saved_sender, (long) uid);
    if (encoding)
	rec_fprintf(dst, REC_TYPE_ATTR, "%s=%s", MAIL_ATTR_ENCODING, encoding);
    if (DEL_REQ_TRACE_FLAGS(flags))
	rec_fprintf(dst, REC_TYPE_ATTR, "%s=%d", MAIL_ATTR_TRACE_FLAGS,
		    DEL_REQ_TRACE_FLAGS(flags));
    if (verp_delims)
	rec_fputs(dst, REC_TYPE_VERP, verp_delims);
    if (recipients) {
	for (cpp = recipients; *cpp != 0; cpp++) {
	    tree = tok822_parse(*cpp);
	    for (addr_count = 0, tp = tree; tp != 0; tp = tp->next) {
		if (tp->type == TOK822_ADDR) {
		    tok822_internalize(buf, tp->head, TOK822_STR_DEFL);
		    if (dsn_notify)
			rec_fprintf(dst, REC_TYPE_ATTR, "%s=%d",
				    MAIL_ATTR_DSN_NOTIFY, dsn_notify);
		    if (REC_PUT_BUF(dst, REC_TYPE_RCPT, buf) < 0)
			msg_fatal_status(EX_TEMPFAIL,
				    "%s(%ld): error writing queue file: %m",
					 saved_sender, (long) uid);
		    ++rcpt_count;
		    ++addr_count;
		}
	    }
	    tok822_free_tree(tree);
	    if (addr_count == 0) {
		if (rec_put(dst, REC_TYPE_RCPT, "", 0) < 0)
		    msg_fatal_status(EX_TEMPFAIL,
				     "%s(%ld): error writing queue file: %m",
				     saved_sender, (long) uid);
		++rcpt_count;
	    }
	}
    }

    /*
     * Append the message contents to the queue file. Write chunks of at most
     * 1kbyte. Internally, we use different record types for data ending in
     * LF and for data that doesn't, so we can actually be binary transparent
     * for local mail. Unfortunately, SMTP has no record continuation
     * convention, so there is no guarantee that arbitrary data will be
     * delivered intact via SMTP. Strip leading From_ lines. For the benefit
     * of UUCP environments, also get rid of leading >>>From_ lines.
     */
    rec_fputs(dst, REC_TYPE_MESG, "");
    if (DEL_REQ_TRACE_ONLY(flags) != 0) {
	if (flags & SM_FLAG_XRCPT)
	    msg_fatal_status(EX_USAGE, "%s(%ld): -t option cannot be used with -bv",
			     saved_sender, (long) uid);
	if (*saved_sender)
	    rec_fprintf(dst, REC_TYPE_NORM, "From: %s", saved_sender);
	rec_fprintf(dst, REC_TYPE_NORM, "Subject: probe");
	if (recipients) {
	    rec_fprintf(dst, REC_TYPE_CONT, "To:");
	    for (cpp = recipients; *cpp != 0; cpp++) {
		rec_fprintf(dst, REC_TYPE_NORM, "	%s%s",
			    *cpp, cpp[1] ? "," : "");
	    }
	}
    } else {

	/*
	 * Initialize the MIME processor and set up the callback context.
	 */
	if (flags & SM_FLAG_XRCPT) {
	    state.dst = dst;
	    state.recipients = argv_alloc(2);
	    state.resent_recip = argv_alloc(2);
	    state.resent = 0;
	    state.saved_sender = saved_sender;
	    state.uid = uid;
	    state.temp = vstring_alloc(10);
	    mime_state = mime_state_alloc(MIME_OPT_DISABLE_MIME
					  | MIME_OPT_REPORT_TRUNC_HEADER,
					  output_header,
					  (MIME_STATE_ANY_END) 0,
					  output_text,
					  (MIME_STATE_ANY_END) 0,
					  (MIME_STATE_ERR_PRINT) 0,
					  (void *) &state);
	}

	/*
	 * Process header/body lines.
	 */
	skip_from_ = 1;
	strip_cr = name_code(sm_fix_eol_table, NAME_CODE_FLAG_STRICT_CASE,
			     var_sm_fix_eol);
	if (strip_cr == STRIP_CR_ERROR)
	    msg_fatal_status(EX_USAGE,
		    "invalid %s value: %s", VAR_SM_FIX_EOL, var_sm_fix_eol);
	for (prev_type = 0; (type = rec_streamlf_get(VSTREAM_IN, buf, var_line_limit))
	     != REC_TYPE_EOF; prev_type = type) {
	    if (strip_cr == STRIP_CR_DUNNO && type == REC_TYPE_NORM) {
		if (VSTRING_LEN(buf) > 0 && vstring_end(buf)[-1] == '\r')
		    strip_cr = STRIP_CR_DO;
		else
		    strip_cr = STRIP_CR_DONT;
	    }
	    if (skip_from_) {
		if (type == REC_TYPE_NORM) {
		    start = STR(buf);
		    if (strncmp(start + strspn(start, ">"), "From ", 5) == 0)
			continue;
		}
		skip_from_ = 0;
	    }
	    if (strip_cr == STRIP_CR_DO && type == REC_TYPE_NORM)
		while (VSTRING_LEN(buf) > 0 && vstring_end(buf)[-1] == '\r')
		    vstring_truncate(buf, VSTRING_LEN(buf) - 1);
	    if ((flags & SM_FLAG_AEOF) && prev_type != REC_TYPE_CONT
		&& VSTRING_LEN(buf) == 1 && *STR(buf) == '.')
		break;
	    if (mime_state) {
		mime_errs = mime_state_update(mime_state, type, STR(buf),
					      VSTRING_LEN(buf));
		if (mime_errs)
		    msg_fatal_status(EX_DATAERR,
				"%s(%ld): unable to extract recipients: %s",
				     saved_sender, (long) uid,
				     mime_state_error(mime_errs));
	    } else {
		if (REC_PUT_BUF(dst, type, buf) < 0)
		    msg_fatal_status(EX_TEMPFAIL,
				     "%s(%ld): error writing queue file: %m",
				     saved_sender, (long) uid);
	    }
	}
    }

    /*
     * Finish MIME processing. We need a final mime_state_update() call in
     * order to flush text that is still buffered. That can happen when the
     * last line did not end in newline.
     */
    if (mime_state) {
	mime_errs = mime_state_update(mime_state, REC_TYPE_EOF, "", 0);
	if (mime_errs)
	    msg_fatal_status(EX_DATAERR,
			     "%s(%ld): unable to extract recipients: %s",
			     saved_sender, (long) uid,
			     mime_state_error(mime_errs));
	mime_state = mime_state_free(mime_state);
    }

    /*
     * Append recipient addresses that were extracted from message headers.
     */
    rec_fputs(dst, REC_TYPE_XTRA, "");
    if (flags & SM_FLAG_XRCPT) {
	for (cpp = state.resent ? state.resent_recip->argv :
	     state.recipients->argv; *cpp; cpp++) {
	    if (dsn_notify)
		rec_fprintf(dst, REC_TYPE_ATTR, "%s=%d",
			    MAIL_ATTR_DSN_NOTIFY, dsn_notify);
	    if (rec_put(dst, REC_TYPE_RCPT, *cpp, strlen(*cpp)) < 0)
		msg_fatal_status(EX_TEMPFAIL,
				 "%s(%ld): error writing queue file: %m",
				 saved_sender, (long) uid);
	    ++rcpt_count;
	}
	argv_free(state.recipients);
	argv_free(state.resent_recip);
	vstring_free(state.temp);
    }
    if (rcpt_count == 0)
	msg_fatal_status(EX_USAGE, (flags & SM_FLAG_XRCPT) ?
		 "%s(%ld): No recipient addresses found in message header" :
			 "%s(%ld): Recipient addresses must be specified on"
			 " the command line or via the -t option",
			 saved_sender, (long) uid);

    /*
     * Identify the end of the queue file.
     */
    rec_fputs(dst, REC_TYPE_END, "");

    /*
     * Make sure that the message makes it to the file system. Once we have
     * terminated with successful exit status we cannot lose the message due
     * to "frivolous reasons". If all goes well, prevent the run-time error
     * handler from removing the file.
     */
    if (vstream_ferror(VSTREAM_IN))
	msg_fatal_status(EX_DATAERR, "%s(%ld): error reading input: %m",
			 saved_sender, (long) uid);
    if ((status = mail_stream_finish(handle, (VSTRING *) 0)) != 0)
	msg_fatal_status((status & CLEANUP_STAT_BAD) ? EX_SOFTWARE :
			 (status & CLEANUP_STAT_WRITE) ? EX_TEMPFAIL :
			 EX_UNAVAILABLE, "%s(%ld): %s", saved_sender,
			 (long) uid, cleanup_strerror(status));

    /*
     * Don't leave them in the dark.
     */
    if (DEL_REQ_TRACE_FLAGS(flags)) {
	vstream_printf("Mail Delivery Status Report will be mailed to <%s>.\n",
		       saved_sender);
	vstream_fflush(VSTREAM_OUT);
    }

    /*
     * Cleanup. Not really necessary as we're about to exit, but good for
     * debugging purposes.
     */
    vstring_free(buf);
    myfree(saved_sender);
}
Example #7
0
int     main(int argc, char **argv)
{
    struct stat st;
    int     fd;
    int     c;
    VSTRING *buf;
    int     status;
    MAIL_STREAM *dst;
    int     rec_type;
    static char *segment_info[] = {
	REC_TYPE_POST_ENVELOPE, REC_TYPE_POST_CONTENT, REC_TYPE_POST_EXTRACT, ""
    };
    char  **expected;
    uid_t   uid = getuid();
    ARGV   *import_env;
    const char *error_text;
    char   *attr_name;
    char   *attr_value;
    const char *errstr;
    char   *junk;
    struct timeval start;
    int     saved_errno;
    int     from_count = 0;
    int     rcpt_count = 0;
    int     validate_input = 1;

    /*
     * Fingerprint executables and core dumps.
     */
    MAIL_VERSION_STAMP_ALLOCATE;

    /*
     * Be consistent with file permissions.
     */
    umask(022);

    /*
     * To minimize confusion, make sure that the standard file descriptors
     * are open before opening anything else. XXX Work around for 44BSD where
     * fstat can return EBADF on an open file descriptor.
     */
    for (fd = 0; fd < 3; fd++)
	if (fstat(fd, &st) == -1
	    && (close(fd), open("/dev/null", O_RDWR, 0)) != fd)
	    msg_fatal("open /dev/null: %m");

    /*
     * Set up logging. Censor the process name: it is provided by the user.
     */
    argv[0] = "postdrop";
    msg_vstream_init(argv[0], VSTREAM_ERR);
    msg_syslog_init(mail_task("postdrop"), LOG_PID, LOG_FACILITY);
    set_mail_conf_str(VAR_PROCNAME, var_procname = mystrdup(argv[0]));

    /*
     * Check the Postfix library version as soon as we enable logging.
     */
    MAIL_VERSION_CHECK;

    /*
     * Parse JCL. This program is set-gid and must sanitize all command-line
     * arguments. The configuration directory argument is validated by the
     * mail configuration read routine. Don't do complex things until we have
     * completed initializations.
     */
    while ((c = GETOPT(argc, argv, "c:rv")) > 0) {
	switch (c) {
	case 'c':
	    if (setenv(CONF_ENV_PATH, optarg, 1) < 0)
		msg_fatal("out of memory");
	    break;
	case 'r':				/* forward compatibility */
	    break;
	case 'v':
	    if (geteuid() == 0)
		msg_verbose++;
	    break;
	default:
	    msg_fatal("usage: %s [-c config_dir] [-v]", argv[0]);
	}
    }

    /*
     * Read the global configuration file and extract configuration
     * information. Some claim that the user should supply the working
     * directory instead. That might be OK, given that this command needs
     * write permission in a subdirectory called "maildrop". However we still
     * need to reliably detect incomplete input, and so we must perform
     * record-level I/O. With that, we should also take the opportunity to
     * perform some sanity checks on the input.
     */
    mail_conf_read();
    /* Re-evaluate mail_task() after reading main.cf. */
    msg_syslog_init(mail_task("postdrop"), LOG_PID, LOG_FACILITY);
    get_mail_conf_str_table(str_table);

    /*
     * Mail submission access control. Should this be in the user-land gate,
     * or in the daemon process?
     */
    mail_dict_init();
    if ((errstr = check_user_acl_byuid(VAR_SUBMIT_ACL, var_submit_acl,
				       uid)) != 0)
	msg_fatal("User %s(%ld) is not allowed to submit mail",
		  errstr, (long) uid);

    /*
     * Stop run-away process accidents by limiting the queue file size. This
     * is not a defense against DOS attack.
     */
    if (var_message_limit > 0 && get_file_limit() > var_message_limit)
	set_file_limit((off_t) var_message_limit);

    /*
     * This program is installed with setgid privileges. Strip the process
     * environment so that we don't have to trust the C library.
     */
    import_env = mail_parm_split(VAR_IMPORT_ENVIRON, var_import_environ);
    clean_env(import_env->argv);
    argv_free(import_env);

    if (chdir(var_queue_dir))
	msg_fatal("chdir %s: %m", var_queue_dir);
    if (msg_verbose)
	msg_info("chdir %s", var_queue_dir);

    /*
     * Set up signal handlers and a runtime error handler so that we can
     * clean up incomplete output.
     * 
     * postdrop_sig() uses the in-kernel SIGINT handler address as an atomic
     * variable to prevent nested postdrop_sig() calls. For this reason, the
     * SIGINT handler must be configured before other signal handlers are
     * allowed to invoke postdrop_sig().
     */
    signal(SIGPIPE, SIG_IGN);
    signal(SIGXFSZ, SIG_IGN);

    signal(SIGINT, postdrop_sig);
    signal(SIGQUIT, postdrop_sig);
    if (signal(SIGTERM, SIG_IGN) == SIG_DFL)
	signal(SIGTERM, postdrop_sig);
    if (signal(SIGHUP, SIG_IGN) == SIG_DFL)
	signal(SIGHUP, postdrop_sig);
    msg_cleanup(postdrop_cleanup);

    /* End of initializations. */

    /*
     * Don't trust the caller's time information.
     */
    GETTIMEOFDAY(&start);

    /*
     * Create queue file. mail_stream_file() never fails. Send the queue ID
     * to the caller. Stash away a copy of the queue file name so we can
     * clean up in case of a fatal error or an interrupt.
     */
    dst = mail_stream_file(MAIL_QUEUE_MAILDROP, MAIL_CLASS_PUBLIC,
			   var_pickup_service, 0444);
    attr_print(VSTREAM_OUT, ATTR_FLAG_NONE,
	       SEND_ATTR_STR(MAIL_ATTR_QUEUEID, dst->id),
	       ATTR_TYPE_END);
    vstream_fflush(VSTREAM_OUT);
    postdrop_path = mystrdup(VSTREAM_PATH(dst->stream));

    /*
     * Copy stdin to file. The format is checked so that we can recognize
     * incomplete input and cancel the operation. With the sanity checks
     * applied here, the pickup daemon could skip format checks and pass a
     * file descriptor to the cleanup daemon. These are by no means all
     * sanity checks - the cleanup service and queue manager services will
     * reject messages that lack required information.
     * 
     * If something goes wrong, slurp up the input before responding to the
     * client, otherwise the client will give up after detecting SIGPIPE.
     * 
     * Allow attribute records if the attribute specifies the MIME body type
     * (sendmail -B).
     */
    vstream_control(VSTREAM_IN, CA_VSTREAM_CTL_PATH("stdin"), CA_VSTREAM_CTL_END);
    buf = vstring_alloc(100);
    expected = segment_info;
    /* Override time information from the untrusted caller. */
    rec_fprintf(dst->stream, REC_TYPE_TIME, REC_TYPE_TIME_FORMAT,
		REC_TYPE_TIME_ARG(start));
    for (;;) {
	/* Don't allow PTR records. */
	rec_type = rec_get_raw(VSTREAM_IN, buf, var_line_limit, REC_FLAG_NONE);
	if (rec_type == REC_TYPE_EOF) {		/* request cancelled */
	    mail_stream_cleanup(dst);
	    if (remove(postdrop_path))
		msg_warn("uid=%ld: remove %s: %m", (long) uid, postdrop_path);
	    else if (msg_verbose)
		msg_info("remove %s", postdrop_path);
	    myfree(postdrop_path);
	    postdrop_path = 0;
	    exit(0);
	}
	if (rec_type == REC_TYPE_ERROR)
	    msg_fatal("uid=%ld: malformed input", (long) uid);
	if (strchr(*expected, rec_type) == 0)
	    msg_fatal("uid=%ld: unexpected record type: %d", (long) uid, rec_type);
	if (rec_type == **expected)
	    expected++;
	/* Override time information from the untrusted caller. */
	if (rec_type == REC_TYPE_TIME)
	    continue;
	/* Check these at submission time instead of pickup time. */
	if (rec_type == REC_TYPE_FROM)
	    from_count++;
	if (rec_type == REC_TYPE_RCPT)
	    rcpt_count++;
	/* Limit the attribute types that users may specify. */
	if (rec_type == REC_TYPE_ATTR) {
	    if ((error_text = split_nameval(vstring_str(buf), &attr_name,
					    &attr_value)) != 0) {
		msg_warn("uid=%ld: ignoring malformed record: %s: %.200s",
			 (long) uid, error_text, vstring_str(buf));
		continue;
	    }
#define STREQ(x,y) (strcmp(x,y) == 0)

	    if ((STREQ(attr_name, MAIL_ATTR_ENCODING)
		 && (STREQ(attr_value, MAIL_ATTR_ENC_7BIT)
		     || STREQ(attr_value, MAIL_ATTR_ENC_8BIT)
		     || STREQ(attr_value, MAIL_ATTR_ENC_NONE)))
		|| STREQ(attr_name, MAIL_ATTR_DSN_ENVID)
		|| STREQ(attr_name, MAIL_ATTR_DSN_NOTIFY)
		|| rec_attr_map(attr_name)
		|| (STREQ(attr_name, MAIL_ATTR_RWR_CONTEXT)
		    && (STREQ(attr_value, MAIL_ATTR_RWR_LOCAL)
			|| STREQ(attr_value, MAIL_ATTR_RWR_REMOTE)))
		|| STREQ(attr_name, MAIL_ATTR_TRACE_FLAGS)) {	/* XXX */
		rec_fprintf(dst->stream, REC_TYPE_ATTR, "%s=%s",
			    attr_name, attr_value);
	    } else {
		msg_warn("uid=%ld: ignoring attribute record: %.200s=%.200s",
			 (long) uid, attr_name, attr_value);
	    }
	    continue;
	}
	if (REC_PUT_BUF(dst->stream, rec_type, buf) < 0) {
	    /* rec_get() errors must not clobber errno. */
	    saved_errno = errno;
	    while ((rec_type = rec_get_raw(VSTREAM_IN, buf, var_line_limit,
					   REC_FLAG_NONE)) != REC_TYPE_END
		   && rec_type != REC_TYPE_EOF)
		if (rec_type == REC_TYPE_ERROR)
		    msg_fatal("uid=%ld: malformed input", (long) uid);
	    validate_input = 0;
	    errno = saved_errno;
	    break;
	}
	if (rec_type == REC_TYPE_END)
	    break;
    }
    vstring_free(buf);

    /*
     * As of Postfix 2.7 the pickup daemon discards mail without recipients.
     * Such mail may enter the maildrop queue when "postsuper -r" is invoked
     * before the queue manager deletes an already delivered message. Looking
     * at file ownership is not a good way to make decisions on what mail to
     * discard. Instead, the pickup server now requires that new submissions
     * always have at least one recipient record.
     * 
     * The Postfix sendmail command already rejects mail without recipients.
     * However, in the future postdrop may receive mail via other programs,
     * so we add a redundant recipient check here for future proofing.
     * 
     * The test for the sender address is just for consistency of error
     * reporting (report at submission time instead of pickup time). Besides
     * the segment terminator records, there aren't any other mandatory
     * records in a Postfix submission queue file.
     */
    if (validate_input && (from_count == 0 || rcpt_count == 0)) {
	status = CLEANUP_STAT_BAD;
	mail_stream_cleanup(dst);
    }

    /*
     * Finish the file.
     */
    else if ((status = mail_stream_finish(dst, (VSTRING *) 0)) != 0) {
	msg_warn("uid=%ld: %m", (long) uid);
	postdrop_cleanup();
    }

    /*
     * Disable deletion on fatal error before reporting success, so the file
     * will not be deleted after we have taken responsibility for delivery.
     */
    if (postdrop_path) {
	junk = postdrop_path;
	postdrop_path = 0;
	myfree(junk);
    }

    /*
     * Send the completion status to the caller and terminate.
     */
    attr_print(VSTREAM_OUT, ATTR_FLAG_NONE,
	       SEND_ATTR_INT(MAIL_ATTR_STATUS, status),
	       SEND_ATTR_STR(MAIL_ATTR_WHY, ""),
	       ATTR_TYPE_END);
    vstream_fflush(VSTREAM_OUT);
    exit(status);
}