!346 anolis: bond: broadcast ARP or ND messages to all slaves

Merge Pull Request from: @wang-yufen316 
 
This is achieved by broadcasting ARP or ND packets to all of its slave devices on transmit side. The switch will take further actions based on proper configuration.
A new sysctl knob "net.bonding.broadcast_arp_or_nd" is introduced which controls the behaviour of broadcasting. 
 
Link:https://gitee.com/openeuler/kernel/pulls/346 

Reviewed-by: Yue Haibing <yuehaibing@huawei.com> 
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> 
Acked-by: Xie XiuQi <xiexiuqi@huawei.com> 

Documentation/networking/ip-sysctl.rst

@@ -2663,3 +2663,14 @@ max_dgram_qlen - INTEGER
 
 	Default: 10
 
+
+``/proc/sys/net/bonding/*``
+========================
+
+broadcast_arp_or_nd - INTEGER
+	Control broadcasting ARP or ND messages to all slaves
+
+	0: Not broadcasting
+	1: Broadcasting
+
+	Default: 0

drivers/net/bonding/Makefile

@@ -5,7 +5,7 @@
 
 obj-$(CONFIG_BONDING) += bonding.o
 
-bonding-objs := bond_main.o bond_3ad.o bond_alb.o bond_sysfs.o bond_sysfs_slave.o bond_debugfs.o bond_netlink.o bond_options.o
+bonding-objs := bond_main.o bond_3ad.o bond_alb.o bond_sysfs.o bond_sysfs_slave.o bond_debugfs.o bond_netlink.o bond_options.o bond_sysctl.o
 
 proc-$(CONFIG_PROC_FS) += bond_procfs.o
 bonding-objs += $(proc-y)

drivers/net/bonding/bond_main.c

@@ -4549,6 +4549,39 @@ int bond_update_slave_arr(struct bonding *bond, struct slave *skipslave)
 	return ret;
 }
 
+/* Check whether the skb is arp or nd msg */
+static inline bool skb_is_arp_or_nd(struct sk_buff *skb)
+{
+	switch (ntohs(skb->protocol)) {
+	case ETH_P_ARP:
+		return true;
+	case ETH_P_IPV6:
+		if (pskb_may_pull(skb, sizeof(struct ipv6hdr) +
+				  sizeof(struct nd_msg))) {
+			struct ipv6hdr *hdr = ipv6_hdr(skb);
+			u8 nexthdr = hdr->nexthdr;
+			struct icmp6hdr *icmp6;
+
+			if (nexthdr == IPPROTO_ICMPV6) {
+				icmp6 = icmp6_hdr(skb);
+
+				if ((icmp6->icmp6_type ==
+				     NDISC_NEIGHBOUR_SOLICITATION ||
+				    icmp6->icmp6_type ==
+				    NDISC_NEIGHBOUR_ADVERTISEMENT) &&
+				    icmp6->icmp6_code == 0) {
+					return true;
+				}
+			}
+		}
+	}
+
+	return false;
+}
+
+static netdev_tx_t bond_xmit_broadcast(struct sk_buff *skb,
+				       struct net_device *bond_dev);
+
 static struct slave *bond_xmit_3ad_xor_slave_get(struct bonding *bond,
 						 struct sk_buff *skb,
 						 struct bond_up_slave *slaves)
@@ -4577,6 +4610,10 @@ static netdev_tx_t bond_3ad_xor_xmit(struct sk_buff *skb,
 	struct bond_up_slave *slaves;
 	struct slave *slave;
 
+	/* Broadcast to all slaves. */
+	if (sysctl_bond_broadcast_arp_or_nd && skb_is_arp_or_nd(skb))
+		return bond_xmit_broadcast(skb, dev);
+
 	slaves = rcu_dereference(bond->usable_slaves);
 	slave = bond_xmit_3ad_xor_slave_get(bond, skb, slaves);
 	if (likely(slave))
@@ -5493,6 +5530,7 @@ static int __init bonding_init(void)
 		goto err_link;
 
 	bond_create_debugfs();
+	bond_create_sysctl();
 
 	for (i = 0; i < max_bonds; i++) {
 		res = bond_create(&init_net, NULL);
@@ -5509,6 +5547,7 @@ static int __init bonding_init(void)
 	return res;
 err:
 	bond_destroy_debugfs();
+	bond_destroy_sysctl();
 	bond_netlink_fini();
 err_link:
 	unregister_pernet_subsys(&bond_net_ops);
@@ -5521,6 +5560,7 @@ static void __exit bonding_exit(void)
 	unregister_netdevice_notifier(&bond_netdev_notifier);
 
 	bond_destroy_debugfs();
+	bond_destroy_sysctl();
 
 	bond_netlink_fini();
 	unregister_pernet_subsys(&bond_net_ops);

drivers/net/bonding/bond_sysctl.c

+// SPDX-License-Identifier: GPL-2.0
+#include <net/net_namespace.h>
+#include <linux/sysctl.h>
+#include <net/bonding.h>
+
+int sysctl_bond_broadcast_arp_or_nd __read_mostly;
+EXPORT_SYMBOL(sysctl_bond_broadcast_arp_or_nd);
+
+struct ctl_table_header *bond_broadcast_arp_or_nd_table_header;
+
+static struct ctl_table bond_broadcast_arp_or_nd_table[] = {
+	{
+		.procname	= "broadcast_arp_or_nd",
+		.data		= &sysctl_bond_broadcast_arp_or_nd,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec,
+	},
+	{}
+};
+
+void bond_create_sysctl(void)
+{
+	bond_broadcast_arp_or_nd_table_header =
+		register_net_sysctl(&init_net, "net/bonding",
+				    bond_broadcast_arp_or_nd_table);
+}
+
+void bond_destroy_sysctl(void)
+{
+	unregister_net_sysctl_table(bond_broadcast_arp_or_nd_table_header);
+}

include/net/bonding.h

@@ -114,6 +114,8 @@ static inline int is_netpoll_tx_blocked(struct net_device *dev)
 #define is_netpoll_tx_blocked(dev) (0)
 #endif
 
+extern int sysctl_bond_broadcast_arp_or_nd;
+
 struct bond_params {
 	int mode;
 	int xmit_policy;
@@ -659,6 +661,8 @@ struct bond_vlan_tag *bond_verify_device_path(struct net_device *start_dev,
 int bond_update_slave_arr(struct bonding *bond, struct slave *skipslave);
 void bond_slave_arr_work_rearm(struct bonding *bond, unsigned long delay);
 void bond_work_init_all(struct bonding *bond);
+void bond_create_sysctl(void);
+void bond_destroy_sysctl(void);
 
 #ifdef CONFIG_PROC_FS
 void bond_create_proc_entry(struct bonding *bond);