Add RTM_NEWADDR and RTM_DELADDR netlink messages with family
AF_UNSPEC to indicate interest in specific unicast and multicast
hardware addresses. These messages are sent when addresses are
added or deleted from the appropriate interface driver.
Added AF_UNSPEC GETADDR function to allow the netlink notifications
to be replayed to avoid loss of state due to application start
ordering or restart.
Signed-off-by: Patrick Ruddy <pru...@brocade.com>
---
include/linux/netdevice.h | 1 +
net/core/dev_addr_lists.c | 157 ++++++++++++++++++++++++++++++++++++++++++++--
net/core/rtnetlink.c | 8 ++-
3 files changed, 161 insertions(+), 5 deletions(-)
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 2095b6a..2029618 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -3751,6 +3751,7 @@ int dev_mc_sync_multiple(struct net_device *to, struct
net_device *from);
void dev_mc_unsync(struct net_device *to, struct net_device *from);
void dev_mc_flush(struct net_device *dev);
void dev_mc_init(struct net_device *dev);
+int unspec_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb);
/**
* __dev_mc_sync - Synchonize device's multicast list
diff --git a/net/core/dev_addr_lists.c b/net/core/dev_addr_lists.c
index c0548d2..70343e6 100644
--- a/net/core/dev_addr_lists.c
+++ b/net/core/dev_addr_lists.c
@@ -12,9 +12,17 @@
*/
#include <linux/netdevice.h>
+#include <net/netlink.h>
#include <linux/rtnetlink.h>
#include <linux/export.h>
#include <linux/list.h>
+#include <net/sock.h>
+
+enum unspec_addr_idx {
+ UNSPEC_UCAST = 0,
+ UNSPEC_MCAST,
+ UNSPEC_MAX
+};
/*
* General list handling functions
@@ -477,6 +485,139 @@ out:
}
EXPORT_SYMBOL(dev_uc_add_excl);
+static int fill_addr(struct sk_buff *skb, struct net_device *dev,
+ const unsigned char *addr, u32 seq, int type,
+ int addr_type, int ifa_flags, unsigned int flags)
+{
+ struct nlmsghdr *nlh;
+ struct ifaddrmsg *ifm;
+
+ nlh = nlmsg_put(skb, 0, seq, type, sizeof(*ifm), flags);
+ if (!nlh)
+ return -EMSGSIZE;
+
+ ifm = nlmsg_data(nlh);
+ ifm->ifa_family = AF_UNSPEC;
+ ifm->ifa_prefixlen = 0;
+ ifm->ifa_flags = ifa_flags;
+ ifm->ifa_scope = RT_SCOPE_LINK;
+ ifm->ifa_index = dev->ifindex;
+ if (nla_put(skb, addr_type, dev->addr_len, addr))
+ goto nla_put_failure;
+ nlmsg_end(skb, nlh);
+ return 0;
+
+nla_put_failure:
+ nlmsg_cancel(skb, nlh);
+ return -EMSGSIZE;
+}
+
+static inline size_t addr_nlmsg_size(void)
+{
+ return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
+ + nla_total_size(MAX_ADDR_LEN);
+}
+
+static void addr_notify(struct net_device *dev, const unsigned char *addr,
+ int type, int addr_type)
+{
+ struct net *net = dev_net(dev);
+ struct sk_buff *skb;
+ int err = -ENOBUFS;
+
+ skb = nlmsg_new(addr_nlmsg_size(), GFP_ATOMIC);
+ if (!skb)
+ goto errout;
+
+ err = fill_addr(skb, dev, addr, 0, type, addr_type, IFA_F_SECONDARY,
+ 0);
+ if (err < 0) {
+ WARN_ON(err == -EMSGSIZE);
+ kfree_skb(skb);
+ goto errout;
+ }
+ rtnl_notify(skb, net, 0, RTNLGRP_LINK, NULL, GFP_ATOMIC);
+ return;
+errout:
+ if (err < 0)
+ rtnl_set_sk_err(net, RTNLGRP_LINK, err);
+}
+
+int unspec_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
+{
+ struct net *net = sock_net(skb->sk);
+ struct net_device *dev;
+ struct hlist_head *head;
+ struct netdev_hw_addr_list *list;
+ struct netdev_hw_addr *ha;
+ int h, s_h;
+ int idx = 0, s_idx;
+ int mac_idx = 0, s_mac_idx;
+ enum unspec_addr_idx addr_idx = 0, s_addr_idx;
+ int err = 0;
+
+ s_h = cb->args[0];
+ s_idx = cb->args[1];
+ s_addr_idx = cb->args[2];
+ s_mac_idx = cb->args[3];
+
+ rcu_read_lock();
+ for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
+ idx = 0;
+ head = &net->dev_index_head[h];
+ cb->seq = atomic_read(&net->ipv4.dev_addr_genid) ^
+ net->dev_base_seq;
+ hlist_for_each_entry_rcu(dev, head, index_hlist) {
+ if (idx < s_idx)
+ goto cont;
+ if (h > s_h || idx > s_idx)
+ s_mac_idx = 0;
+ for (addr_idx = 0; addr_idx < UNSPEC_MAX;
+ addr_idx++, s_addr_idx = 0) {
+ if (addr_idx < s_addr_idx)
+ continue;
+ list = (addr_idx == UNSPEC_UCAST) ? &dev->uc :
+ &dev->mc;
+ if (netdev_hw_addr_list_empty(list))
+ continue;
+ mac_idx = 0;
+ list_for_each_entry(ha, &list->list, list) {
+ if (mac_idx < s_mac_idx) {
+ mac_idx++;
+ continue;
+ }
+ err = fill_addr(skb, dev, ha->addr,
+ cb->nlh->nlmsg_seq,
+ RTM_NEWADDR,
+ (addr_idx ==
+ UNSPEC_UCAST) ?
+ IFA_ADDRESS :
+ IFA_MULTICAST,
+ IFA_F_SECONDARY,
+ NLM_F_MULTI);
+ if (err < 0)
+ goto done;
+ nl_dump_check_consistent(cb,
+ nlmsg_hdr(skb)
+ );
+ mac_idx++;
+ }
+ s_mac_idx = 0;
+ }
+cont:
+ idx++;
+ }
+ }
+done:
+ rcu_read_unlock();
+ cb->args[0] = h;
+ cb->args[1] = idx;
+ cb->args[2] = addr_idx;
+ cb->args[3] = mac_idx;
+
+ return skb->len;
+}
+
/**
* dev_uc_add - Add a secondary unicast address
* @dev: device
@@ -492,8 +633,10 @@ int dev_uc_add(struct net_device *dev, const unsigned char
*addr)
netif_addr_lock_bh(dev);
err = __hw_addr_add(&dev->uc, addr, dev->addr_len,
NETDEV_HW_ADDR_T_UNICAST);
- if (!err)
+ if (!err) {
__dev_set_rx_mode(dev);
+ addr_notify(dev, addr, RTM_NEWADDR, IFA_ADDRESS);
+ }
netif_addr_unlock_bh(dev);
return err;
}
@@ -514,8 +657,10 @@ int dev_uc_del(struct net_device *dev, const unsigned char
*addr)
netif_addr_lock_bh(dev);
err = __hw_addr_del(&dev->uc, addr, dev->addr_len,
NETDEV_HW_ADDR_T_UNICAST);
- if (!err)
+ if (!err) {
__dev_set_rx_mode(dev);
+ addr_notify(dev, addr, RTM_DELADDR, IFA_ADDRESS);
+ }
netif_addr_unlock_bh(dev);
return err;
}
@@ -669,8 +814,10 @@ static int __dev_mc_add(struct net_device *dev, const
unsigned char *addr,
netif_addr_lock_bh(dev);
err = __hw_addr_add_ex(&dev->mc, addr, dev->addr_len,
NETDEV_HW_ADDR_T_MULTICAST, global, false, 0);
- if (!err)
+ if (!err) {
__dev_set_rx_mode(dev);
+ addr_notify(dev, addr, RTM_NEWADDR, IFA_MULTICAST);
+ }
netif_addr_unlock_bh(dev);
return err;
}
@@ -709,8 +856,10 @@ static int __dev_mc_del(struct net_device *dev, const
unsigned char *addr,
netif_addr_lock_bh(dev);
err = __hw_addr_del_ex(&dev->mc, addr, dev->addr_len,
NETDEV_HW_ADDR_T_MULTICAST, global, false);
- if (!err)
+ if (!err) {
__dev_set_rx_mode(dev);
+ addr_notify(dev, addr, RTM_DELADDR, IFA_MULTICAST);
+ }
netif_addr_unlock_bh(dev);
return err;
}
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index 937e459..e6292bb 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -2686,8 +2686,14 @@ static int rtnl_dump_all(struct sk_buff *skb, struct
netlink_callback *cb)
int idx;
int s_idx = cb->family;
- if (s_idx == 0)
+ if (s_idx == 0) {
+ if (unspec_dump_ifaddr(skb, cb))
+ return skb->len;
+ memset(&cb->args[0], 0, sizeof(cb->args));
+ cb->prev_seq = 0;
+ cb->seq = 0;
s_idx = 1;
+ }
for (idx = 1; idx <= RTNL_FAMILY_MAX; idx++) {
int type = cb->nlh->nlmsg_type-RTM_BASE;
if (idx < s_idx || idx == PF_PACKET)
--
2.1.4
