[PATCH iproute2-next 1/2] iplink: bridge_slave: Add support for neigh_forward_grat

[Danielle Ratson <danieller@nvidia.com>]

Add support for controlling gratuitous ARP and unsolicited NA
forwarding at the port level via the neigh_forward_grat option.

This allows configuring the option via:
$ ip link set dev <port> type bridge_slave neigh_forward_grat {on|off}

Or via the bridge command:
$ bridge link set dev <port> neigh_forward_grat {on|off}

Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Danielle Ratson <danieller@nvidia.com>
---
 bridge/link.c            | 14 ++++++++++++++
 ip/iplink_bridge_slave.c | 10 ++++++++++
 man/man8/bridge.8        | 10 ++++++++++
 man/man8/ip-link.8.in    | 10 ++++++++++
 4 files changed, 44 insertions(+)

diff --git a/bridge/link.c b/bridge/link.c
index 7638797d..370d7de4 100644
--- a/bridge/link.c
+++ b/bridge/link.c
@@ -174,6 +174,9 @@ static void print_protinfo(FILE *fp, struct rtattr *attr)
 				     "neigh_vlan_suppress %s ",
 				     rta_getattr_u8(at));
 		}
+		if (prtb[IFLA_BRPORT_NEIGH_FORWARD_GRAT])
+			print_on_off(PRINT_ANY, "neigh_forward_grat", "neigh_forward_grat %s ",
+				     rta_getattr_u8(prtb[IFLA_BRPORT_NEIGH_FORWARD_GRAT]));
 		if (prtb[IFLA_BRPORT_VLAN_TUNNEL])
 			print_on_off(PRINT_ANY, "vlan_tunnel", "vlan_tunnel %s ",
 				     rta_getattr_u8(prtb[IFLA_BRPORT_VLAN_TUNNEL]));
@@ -313,6 +316,7 @@ static void usage(void)
 		"                               [ mcast_max_groups MAX_GROUPS ]\n"
 		"                               [ neigh_suppress {on | off} ]\n"
 		"                               [ neigh_vlan_suppress {on | off} ]\n"
+		"                               [ neigh_forward_grat {on | off} ]\n"
 		"                               [ vlan_tunnel {on | off} ]\n"
 		"                               [ isolated {on | off} ]\n"
 		"                               [ locked {on | off} ]\n"
@@ -343,6 +347,7 @@ static int brlink_modify(int argc, char **argv)
 	int backup_port_idx = -1;
 	__s8 neigh_suppress = -1;
 	__s8 neigh_vlan_suppress = -1;
+	__s8 neigh_forward_grat = -1;
 	__s8 learning = -1;
 	__s8 learning_sync = -1;
 	__s8 flood = -1;
@@ -474,6 +479,12 @@ static int brlink_modify(int argc, char **argv)
 							   *argv, &ret);
 			if (ret)
 				return ret;
+		} else if (strcmp(*argv, "neigh_forward_grat") == 0) {
+			NEXT_ARG();
+			neigh_forward_grat = parse_on_off("neigh_forward_grat",
+							  *argv, &ret);
+			if (ret)
+				return ret;
 		} else if (strcmp(*argv, "vlan_tunnel") == 0) {
 			NEXT_ARG();
 			vlan_tunnel = parse_on_off("vlan_tunnel", *argv, &ret);
@@ -579,6 +590,9 @@ static int brlink_modify(int argc, char **argv)
 	if (neigh_vlan_suppress != -1)
 		addattr8(&req.n, sizeof(req), IFLA_BRPORT_NEIGH_VLAN_SUPPRESS,
 			 neigh_vlan_suppress);
+	if (neigh_forward_grat != -1)
+		addattr8(&req.n, sizeof(req), IFLA_BRPORT_NEIGH_FORWARD_GRAT,
+			 neigh_forward_grat);
 	if (vlan_tunnel != -1)
 		addattr8(&req.n, sizeof(req), IFLA_BRPORT_VLAN_TUNNEL,
 			 vlan_tunnel);
diff --git a/ip/iplink_bridge_slave.c b/ip/iplink_bridge_slave.c
index 3821923b..1be02041 100644
--- a/ip/iplink_bridge_slave.c
+++ b/ip/iplink_bridge_slave.c
@@ -38,6 +38,7 @@ static void print_explain(FILE *f)
 		"			[ group_fwd_mask MASK ]\n"
 		"			[ neigh_suppress {on | off} ]\n"
 		"			[ neigh_vlan_suppress {on | off} ]\n"
+		"			[ neigh_forward_grat {on | off} ]\n"
 		"			[ vlan_tunnel {on | off} ]\n"
 		"			[ isolated {on | off} ]\n"
 		"			[ locked {on | off} ]\n"
@@ -275,6 +276,11 @@ static void bridge_slave_print_opt(struct link_util *lu, FILE *f,
 			     "neigh_vlan_suppress %s ",
 			     rta_getattr_u8(tb[IFLA_BRPORT_NEIGH_VLAN_SUPPRESS]));
 
+	if (tb[IFLA_BRPORT_NEIGH_FORWARD_GRAT])
+		print_on_off(PRINT_ANY, "neigh_forward_grat",
+			     "neigh_forward_grat %s ",
+			     rta_getattr_u8(tb[IFLA_BRPORT_NEIGH_FORWARD_GRAT]));
+
 	if (tb[IFLA_BRPORT_GROUP_FWD_MASK]) {
 		char convbuf[256];
 		__u16 fwd_mask;
@@ -415,6 +421,10 @@ static int bridge_slave_parse_opt(struct link_util *lu, int argc, char **argv,
 			NEXT_ARG();
 			bridge_slave_parse_on_off("neigh_vlan_suppress", *argv,
 						  n, IFLA_BRPORT_NEIGH_VLAN_SUPPRESS);
+		} else if (strcmp(*argv, "neigh_forward_grat") == 0) {
+			NEXT_ARG();
+			bridge_slave_parse_on_off("neigh_forward_grat", *argv,
+						  n, IFLA_BRPORT_NEIGH_FORWARD_GRAT);
 		} else if (matches(*argv, "group_fwd_mask") == 0) {
 			__u16 mask;
 
diff --git a/man/man8/bridge.8 b/man/man8/bridge.8
index fe800d3f..aae6c75a 100644
--- a/man/man8/bridge.8
+++ b/man/man8/bridge.8
@@ -55,6 +55,7 @@ bridge \- show / manipulate bridge addresses and devices
 .BR mcast_to_unicast " { " on " | " off " } ] [ "
 .BR neigh_suppress " { " on " | " off " } ] [ "
 .BR neigh_vlan_suppress " { " on " | " off " } ] [ "
+.BR neigh_forward_grat " { " on " | " off " } ] [ "
 .BR vlan_tunnel " { " on " | " off " } ] [ "
 .BR isolated " { " on " | " off " } ] [ "
 .BR locked " { " on " | " off " } ] [ "
@@ -659,6 +660,15 @@ enabled on the port. When on, the \fBbridge link\fR option \fBneigh_suppress\fR
 has no effect and the per-VLAN state is set using the \fBbridge vlan\fR option
 \fBneigh_suppress\fR. By default this flag is off.
 
+.TP
+.BR "neigh_forward_grat on " or " neigh_forward_grat off "
+Controls whether gratuitous ARP packets and unsolicited Neighbor Advertisement
+packets are forwarded when neighbor suppression is enabled on the port.
+By default this flag is off, meaning gratuitous ARP and unsolicited NA packets
+will be suppressed when neighbor suppression is enabled. Setting this flag to
+on allows these packets to be forwarded even when neighbor suppression is
+enabled.
+
 .TP
 .BR "vlan_tunnel on " or " vlan_tunnel off "
 Controls whether vlan to tunnel mapping is enabled on the port. By
diff --git a/man/man8/ip-link.8.in b/man/man8/ip-link.8.in
index ef45fe08..e89b2db3 100644
--- a/man/man8/ip-link.8.in
+++ b/man/man8/ip-link.8.in
@@ -2677,6 +2677,8 @@ the following additional arguments are supported:
 ] [
 .BR neigh_vlan_suppress " { " on " | " off " }"
 ] [
+.BR neigh_forward_grat " { " on " | " off " }"
+] [
 .BR vlan_tunnel " { " on " | " off " }"
 ] [
 .BR isolated " { " on " | " off " }"
@@ -2791,6 +2793,14 @@ is enabled on the port. When on, the \fBbridge link\fR option
 \fBneigh_suppress\fR has no effect and the per-VLAN state is set using the
 \fBbridge vlan\fR option \fBneigh_suppress\fR. By default this flag is off.
 
+.BR neigh_forward_grat " { " on " | " off " }"
+- controls whether gratuitous ARP packets and unsolicited Neighbor
+Advertisement packets are forwarded when neighbor suppression is enabled
+on the port. By default this flag is off, meaning gratuitous ARP and
+unsolicited NA packets will be suppressed when neighbor suppression is
+enabled. Setting this flag to on allows these packets to be forwarded even
+when neighbor suppression is enabled.
+
 .BR vlan_tunnel " { " on " | " off " }"
 - controls whether vlan to tunnel mapping is enabled on the port. By
 default this flag is off.
-- 
2.51.0