add an option to increase the multicast ttl which is currently limited

to 1 hop. by using a higher multicast ttl, you could use inter-network
multicast forwarding of hostapd messages (i.e. with mrouted(8) or
multicast-capable routing switches); "set iapp mode multicast ttl 2".

4 files changed, 34 insertions, 13 deletions

diff --git a/usr.sbin/hostapd/hostapd.c b/usr.sbin/hostapd/hostapd.c
index 81a08942526..595a2384821 100644
--- a/usr.sbin/hostapd/hostapd.c
+++ b/usr.sbin/hostapd/hostapd.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: hostapd.c,v 1.24 2005/12/01 01:11:30 reyk Exp $	*/
+/*	$OpenBSD: hostapd.c,v 1.25 2005/12/10 13:42:37 reyk Exp $	*/
 
 /*
  * Copyright (c) 2004, 2005 Reyk Floeter <reyk@vantronix.net>
@@ -255,19 +255,16 @@ hostapd_udp_init(struct hostapd_config *cfg)
 		/*
 		 * Enable broadcast
 		 */
-
-		hostapd_log(HOSTAPD_LOG_DEBUG, "using broadcast mode\n");
-
 		if (setsockopt(iapp->i_udp, SOL_SOCKET, SO_BROADCAST,
 		    &brd, sizeof(brd)) == -1)
 			hostapd_fatal("failed to enable broadcast on socket\n");
+
+		hostapd_log(HOSTAPD_LOG_DEBUG, "%s: using broadcast mode "
+		    "(address %s)\n", iapp->i_iface, inet_ntoa(addr->sin_addr));
 	} else {
 		/*
 		 * Enable multicast
 		 */
-
-		hostapd_log(HOSTAPD_LOG_DEBUG, "using multicast mode\n");
-
 		bzero(&mreq, sizeof(mreq));
 
 		iapp->i_multicast.sin_family = AF_INET;
@@ -285,6 +282,15 @@ hostapd_udp_init(struct hostapd_config *cfg)
 		    IP_ADD_MEMBERSHIP, &mreq, sizeof(mreq)) == -1)
 			hostapd_fatal("failed to add multicast membership to "
 			    "%s: %s\n", IAPP_MCASTADDR, strerror(errno));
+
+		if (setsockopt(iapp->i_udp, IPPROTO_IP, IP_MULTICAST_TTL,
+		    &iapp->i_ttl, sizeof(iapp->i_ttl)) < 0)
+			hostapd_fatal("failed to set multicast ttl to "
+			    "%u: %s\n", iapp->i_ttl, strerror(errno));
+
+		hostapd_log(HOSTAPD_LOG_DEBUG, "%s: using multicast mode "
+		    "(ttl %u, group %s)\n", iapp->i_iface, iapp->i_ttl,
+		    inet_ntoa(iapp->i_multicast.sin_addr));
 	}
 }
 
diff --git a/usr.sbin/hostapd/hostapd.conf.5 b/usr.sbin/hostapd/hostapd.conf.5
index e1dbf8f1427..42b6030191e 100644
--- a/usr.sbin/hostapd/hostapd.conf.5
+++ b/usr.sbin/hostapd/hostapd.conf.5
@@ -1,4 +1,4 @@
-.\" $OpenBSD: hostapd.conf.5,v 1.25 2005/12/01 08:28:58 jmc Exp $
+.\" $OpenBSD: hostapd.conf.5,v 1.26 2005/12/10 13:42:37 reyk Exp $
 .\"
 .\" Copyright (c) 2004, 2005 Reyk Floeter <reyk@vantronix.net>
 .\"
@@ -174,8 +174,12 @@ The supported modes are:
 .Ic multicast
 .Op Ic address Ar ipv4addr
 .Op Ic port Ar number
+.Op Ic ttl Ar number
 .Xc
 Use multicast frames.
+A multicast ttl (time-to-live) of 2 or higher is required to allow
+multicast forwarding, for example with
+.Xr mrouted 8 .
 .It Xo
 .Ic broadcast
 .Op Ic port Ar number
@@ -183,7 +187,8 @@ Use multicast frames.
 Use broadcast frames.
 .El
 .Pp
-The default is multicast using the multicast address 224.0.1.178.
+The default is multicast using the multicast address 224.0.1.178 with a ttl
+limited to 1 hop.
 .El
 .Sh EVENT RULES
 Event rules provide a powerful way to trigger a certain action when
diff --git a/usr.sbin/hostapd/hostapd.h b/usr.sbin/hostapd/hostapd.h
index 89191156a4f..50044830924 100644
--- a/usr.sbin/hostapd/hostapd.h
+++ b/usr.sbin/hostapd/hostapd.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: hostapd.h,v 1.14 2005/12/01 02:03:58 reyk Exp $	*/
+/*	$OpenBSD: hostapd.h,v 1.15 2005/12/10 13:42:37 reyk Exp $	*/
 
 /*
  * Copyright (c) 2004, 2005 Reyk Floeter <reyk@vantronix.net>
@@ -263,6 +263,7 @@ struct hostapd_iapp {
 	struct sockaddr_in		i_addr;
 	struct sockaddr_in		i_broadcast;
 	struct sockaddr_in		i_multicast;
+	u_int8_t			i_ttl;
 	u_int8_t			i_flags;
 
 #define HOSTAPD_IAPP_F_ADD_NOTIFY	0x01
diff --git a/usr.sbin/hostapd/parse.y b/usr.sbin/hostapd/parse.y
index 0220e6aac19..8032745d288 100644
--- a/usr.sbin/hostapd/parse.y
+++ b/usr.sbin/hostapd/parse.y
@@ -1,4 +1,4 @@
-/*	$OpenBSD: parse.y,v 1.17 2005/12/01 02:03:58 reyk Exp $	*/
+/*	$OpenBSD: parse.y,v 1.18 2005/12/10 13:42:37 reyk Exp $	*/
 
 /*
  * Copyright (c) 2004, 2005 Reyk Floeter <reyk@vantronix.net>
@@ -127,7 +127,7 @@ u_int negative;
 %token	ERROR CONST TABLE NODE DELETE ADD LOG VERBOSE LIMIT QUICK SKIP
 %token	REASON UNSPECIFIED EXPIRE LEAVE ASSOC TOOMANY NOT AUTHED ASSOCED
 %token	RESERVED RSN REQUIRED INCONSISTENT IE INVALID MIC FAILURE OPEN
-%token	ADDRESS PORT ON NOTIFY
+%token	ADDRESS PORT ON NOTIFY TTL
 %token	<v.string>	STRING
 %token	<v.val>		VALUE
 %type	<v.val>		number
@@ -175,7 +175,7 @@ option		: SET HOSTAP INTERFACE hostapifaces
 		| SET IAPP HANDLE SUBTYPE iappsubtypes
 		;
 
-iappmode	: MULTICAST iappmodeaddr iappmodeport
+iappmode	: MULTICAST iappmodeaddr iappmodeport iappmodettl
 		{
 			hostapd_cfg.c_flags &= ~HOSTAPD_CFG_F_BRDCAST;
 		}
@@ -200,6 +200,13 @@ iappmodeport	: /* empty */
 		}
 		;
 
+iappmodettl	: /* empty */
+		| TTL number
+		{
+			hostapd_cfg.c_iapp.i_ttl = $2;
+		}
+		;
+
 hostapmode	: RADIOTAP
 		{
 			hostapd_cfg.c_apme_dlt = DLT_IEEE802_11_RADIO;
@@ -1026,6 +1033,7 @@ lookup(char *token)
 		{ "table",		TABLE },
 		{ "to",			TO },
 		{ "toomany",		TOOMANY },
+		{ "ttl",		TTL },
 		{ "type",		TYPE },
 		{ "unspecified",	UNSPECIFIED },
 		{ "usec",		USEC },
@@ -1327,6 +1335,7 @@ hostapd_parse_file(struct hostapd_config *cfg)
 	TAILQ_INIT(&cfg->c_frames);
 	cfg->c_iapp.i_multicast.sin_addr.s_addr = INADDR_ANY;
 	cfg->c_iapp.i_flags = HOSTAPD_IAPP_F_DEFAULT;
+	cfg->c_iapp.i_ttl = IP_DEFAULT_MULTICAST_TTL;
 
 	lineno = 1;
 	errors = 0;