Reviewed by: various

Submitted by:	archie@whistle.com

allow ftpd to bind to a single address/interface
this allows easy split services.

libexec/ftpd/ftpd.8

@@ -47,6 +47,8 @@ Internet File Transfer Protocol server
 .Op Fl U
 .Op Fl T Ar maxtimeout
 .Op Fl t Ar timeout
+.Op Fl a Ar address
+.Op Fl p Ar file
 .Sh DESCRIPTION
 .Nm Ftpd
 is the
@@ -117,6 +119,16 @@ The default limit is 2 hours.
 The inactivity timeout period is set to
 .Ar timeout
 seconds (the default is 15 minutes).
+.It Fl a
+When
+.Fl D
+is specified, accept connections only on the specified
+.Ar address .
+.It Fl p
+When
+.Fl D
+is specified, write the daemon's process ID to
+.Ar file .
 .El
 .Pp
 The file

libexec/ftpd/ftpd.c

@@ -30,7 +30,7 @@
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
- *	$Id$
+ *	$Id: ftpd.c,v 1.22 1996/08/09 09:02:26 markm Exp $
  */
 
 #if 0
@@ -152,6 +152,9 @@ char	*tty = ttyline;		/* for klogin */
 int	 klogin __P((struct passwd *, char *, char *, char *));
 #endif
 
+struct	in_addr bind_address;
+char	*pid_file = NULL;
+
 #if defined(KERBEROS)
 int	notickets = 1;
 int	noticketsdontcomplain = 1;
@@ -255,7 +258,8 @@ main(argc, argv, envp)
 #endif /* OLD_SETPROCTITLE */
 
 
-	while ((ch = getopt(argc, argv, "dlDSUt:T:u:v")) != EOF) {
+	bind_address.s_addr = htonl(INADDR_ANY);
+	while ((ch = getopt(argc, argv, "dlDSUt:T:u:va:p:")) != EOF) {
 		switch (ch) {
 		case 'D':
 			daemon_mode++;
@@ -293,6 +297,15 @@ main(argc, argv, envp)
 			restricted_data_ports = 0;
 			break;
 
+		case 'a':
+			if (!inet_aton(optarg, &bind_address))
+				errx(1, "invalid address for -a");
+			break;
+
+		case 'p':
+			pid_file = optarg;
+			break;
+
 		case 'u':
 		    {
 			long val = 0;
@@ -356,7 +369,7 @@ main(argc, argv, envp)
 		    (char *)&on, sizeof(on)) < 0)
 			syslog(LOG_ERR, "control setsockopt: %m");;
 		server_addr.sin_family = AF_INET;
-		server_addr.sin_addr.s_addr = INADDR_ANY;
+		server_addr.sin_addr = bind_address;
 		server_addr.sin_port = sv->s_port;
 		if (bind(ctl_sock, (struct sockaddr *)&server_addr, sizeof(server_addr))) {
 			syslog(LOG_ERR, "control bind: %m");
@@ -366,6 +379,27 @@ main(argc, argv, envp)
 			syslog(LOG_ERR, "control listen: %m");
 			exit(1);
 		}
+		/*
+		 * Atomically write process ID
+		 */
+		if (pid_file)
+		{   
+			int fd;
+			char buf[20];
+
+			fd = open(pid_file, O_CREAT | O_WRONLY | O_TRUNC
+				| O_NONBLOCK | O_EXLOCK, 0644);
+			if (fd < 0)
+				if (errno == EAGAIN)
+					errx(1, "%s: file locked", pid_file);
+				else
+					err(1, "%s", pid_file);
+			snprintf(buf, sizeof(buf),
+				"%lu\n", (unsigned long) getpid());
+			if (write(fd, buf, strlen(buf)) < 0)
+				err(1, "%s: write", pid_file);
+			/* Leave the pid file open and locked */
+		}
 		/*
 		 * Loop forever accepting connection requests and forking off
 		 * children to handle them.