[patch v3, kernel version 3.2.1] Source mode for macvlan interface

From: Stefan Gula
Date: Tue Jan 24 2012 - 09:59:21 EST


From: Stefan Gula <steweg@xxxxxxxxx>

New mode of macvlan interface called "source" allows one to set a list
of allowed mac address, which is used to match against source mac
address from received frames on underlying interface. This allows
creating mac based VLAN associations, instead of standard port or tag
based. The feature is useful to deploy 802.1x mac based behavior,
where drivers of underlying interfaces doesn't allows that.
Configuration is done through the netlink interface using e.g.:
ip link add link eth0 name macvlan0 type macvlan mode source
ip link add link eth0 name macvlan1 type macvlan mode source
ip link set link macvlan0 type macvlan macaddr add 00:11:11:11:11:11
ip link set link macvlan0 type macvlan macaddr add 00:22:22:22:22:22
ip link set link macvlan0 type macvlan macaddr add 00:33:33:33:33:33
ip link set link macvlan1 type macvlan macaddr add 00:33:33:33:33:33
ip link set link macvlan1 type macvlan macaddr add 00:44:44:44:44:44
This allows clients with MAC addresses 00:11:11:11:11:11,
00:22:22:22:22:22 to be part of only VLAN associated with macvlan0
interface. Clients with MAC addresses 00:44:44:44:44:44 with only VLAN
associated with macvlan1 interface. And client with MAC address
00:33:33:33:33:33 to be associated with both VLANs.

Signed-off-by: Stefan Gula <steweg@xxxxxxxxx>

---

V3: list of changes:
- changed GFP_ATOMIC to GFP_KERNEL
- modified rtnetlink.c to automatic adjust min_ifinfo_dump_size during
do_setlink to adjust size of allocated sk_buff structure
- removed IFLA_MACVLAN_MACADDR_ADT - not needed anymore

diff -uprN -X linux/Documentation/dontdiff linux-3.2.1-orig/drivers/net/macvlan.c linux/drivers/net/macvlan.c
--- linux-3.2.1-orig/drivers/net/macvlan.c 2012-01-12 20:42:45.000000000 +0100
+++ linux/drivers/net/macvlan.c 2012-01-24 14:25:38.176220426 +0100
@@ -40,6 +40,7 @@ struct macvlan_port {
struct rcu_head rcu;
bool passthru;
int count;
+ struct hlist_head vlan_source_hash[MACVLAN_HASH_SIZE];
};

static void macvlan_port_destroy(struct net_device *dev);
@@ -155,6 +156,114 @@ static void macvlan_broadcast(struct sk_
}
}

+struct macvlan_source_list {
+ struct hlist_node hlist;
+ struct macvlan_dev *vlan;
+ unsigned char addr[ETH_ALEN];
+ struct rcu_head rcu;
+};
+
+static struct macvlan_source_list *macvlan_hash_lookup_sources_list(
+ const struct macvlan_dev *vlan,
+ const unsigned char *addr)
+{
+ struct macvlan_source_list *list;
+ struct hlist_node *n;
+
+ hlist_for_each_entry_rcu(list, n,
+ &vlan->port->vlan_source_hash[addr[5]], hlist) {
+ if (!compare_ether_addr_64bits(list->addr, addr) &&
+ list->vlan == vlan)
+ return list;
+ }
+ return NULL;
+}
+
+static int macvlan_hash_add_sources(struct macvlan_dev *vlan,
+ const unsigned char *addr)
+{
+ struct macvlan_port *port = vlan->port;
+ struct macvlan_source_list *list;
+
+ list = macvlan_hash_lookup_sources_list(vlan, addr);
+ if (!list) {
+ list = kmalloc(sizeof(*list), GFP_KERNEL);
+ if (list) {
+ memcpy(list->addr, addr, ETH_ALEN);
+ list->vlan = vlan;
+ hlist_add_head_rcu(&list->hlist,
+ &port->vlan_source_hash[addr[5]]);
+ } else
+ return -ENOMEM;
+ }
+ return 0;
+}
+
+static void macvlan_hash_del_sources(struct macvlan_source_list *list)
+{
+ hlist_del_rcu(&list->hlist);
+ kfree_rcu(list, rcu);
+}
+
+static void macvlan_flush_sources(struct macvlan_port *port,
+ struct macvlan_dev *vlan)
+{
+ int i;
+
+ for (i = 0; i < MACVLAN_HASH_SIZE; i++) {
+ struct hlist_node *h, *n;
+
+ hlist_for_each_safe(h, n, &port->vlan_source_hash[i]) {
+ struct macvlan_source_list *list
+ = hlist_entry(h, struct macvlan_source_list,
+ hlist);
+ if (list->vlan == vlan)
+ macvlan_hash_del_sources(list);
+ }
+ }
+}
+
+static void macvlan_forward_sources_one(struct sk_buff *skb,
+ struct macvlan_dev *vlan)
+{
+ struct sk_buff *nskb;
+ struct net_device *dev;
+ int len;
+ int ret;
+
+ dev = vlan->dev;
+ if (unlikely(!(dev->flags & IFF_UP)))
+ return;
+
+ nskb = skb_clone(skb, GFP_ATOMIC);
+ if (!nskb)
+ return;
+
+ len = nskb->len + ETH_HLEN;
+ nskb->dev = dev;
+ nskb->pkt_type = PACKET_HOST;
+ ret = vlan->receive(nskb);
+ macvlan_count_rx(vlan, len, ret == NET_RX_SUCCESS, 0);
+}
+
+static void macvlan_forward_sources(struct sk_buff *skb,
+ const struct macvlan_port *port,
+ const unsigned char *addr)
+{
+ struct macvlan_source_list *list;
+ struct hlist_node *n;
+
+ hlist_for_each_entry_rcu(list, n, &port->vlan_source_hash[addr[5]],
+ hlist) {
+ if (!compare_ether_addr_64bits(list->addr, addr))
+ if (list->vlan->dev->flags & IFF_UP)
+ macvlan_forward_sources_one(skb, list->vlan);
+ }
+ return;
+}
+
+
+
/* called under rcu_read_lock() from netif_receive_skb */
static rx_handler_result_t macvlan_handle_frame(struct sk_buff **pskb)
{
@@ -172,6 +281,8 @@ static rx_handler_result_t macvlan_handl
skb = ip_check_defrag(skb, IP_DEFRAG_MACVLAN);
if (!skb)
return RX_HANDLER_CONSUMED;
+
+ macvlan_forward_sources(skb, port, eth->h_source);
src = macvlan_hash_lookup(port, eth->h_source);
if (!src)
/* frame comes from an external address */
@@ -202,6 +313,7 @@ static rx_handler_result_t macvlan_handl
return RX_HANDLER_PASS;
}

+ macvlan_forward_sources(skb, port, eth->h_source);
if (port->passthru)
vlan = list_first_entry(&port->vlans, struct macvlan_dev, list);
else
@@ -474,6 +586,7 @@ static void macvlan_uninit(struct net_de

free_percpu(vlan->pcpu_stats);

+ macvlan_flush_sources(port, vlan);
port->count -= 1;
if (!port->count)
macvlan_port_destroy(port->dev);
@@ -615,7 +728,8 @@ static int macvlan_port_create(struct ne
INIT_LIST_HEAD(&port->vlans);
for (i = 0; i < MACVLAN_HASH_SIZE; i++)
INIT_HLIST_HEAD(&port->vlan_hash[i]);
-
+ for (i = 0; i < MACVLAN_HASH_SIZE; i++)
+ INIT_HLIST_HEAD(&port->vlan_source_hash[i]);
err = netdev_rx_handler_register(dev, macvlan_handle_frame, port);
if (err)
kfree(port);
@@ -648,11 +762,31 @@ static int macvlan_validate(struct nlatt
case MACVLAN_MODE_VEPA:
case MACVLAN_MODE_BRIDGE:
case MACVLAN_MODE_PASSTHRU:
+ case MACVLAN_MODE_SOURCE:
+ break;
+ default:
+ return -EINVAL;
+ }
+ }
+
+ if (data && data[IFLA_MACVLAN_MACADDR_MODE]) {
+ switch (nla_get_u32(data[IFLA_MACVLAN_MACADDR_MODE])) {
+ case MACVLAN_MACADDR_ADD:
+ case MACVLAN_MACADDR_DEL:
break;
default:
return -EINVAL;
}
}
+
+ if (data && data[IFLA_MACVLAN_MACADDR]) {
+ if (nla_len(data[IFLA_MACVLAN_MACADDR]) != ETH_ALEN)
+ return -EINVAL;
+
+ if (!is_valid_ether_addr(nla_data(data[IFLA_MACVLAN_MACADDR])))
+ return -EADDRNOTAVAIL;
+ }
+
return 0;
}

@@ -749,6 +883,8 @@ void macvlan_dellink(struct net_device *
{
struct macvlan_dev *vlan = netdev_priv(dev);

+ if (vlan->mode == MACVLAN_MODE_SOURCE)
+ macvlan_flush_sources(vlan->port, vlan);
list_del(&vlan->list);
unregister_netdevice_queue(dev, head);
}
@@ -758,30 +894,120 @@ static int macvlan_changelink(struct net
struct nlattr *tb[], struct nlattr *data[])
{
struct macvlan_dev *vlan = netdev_priv(dev);
- if (data && data[IFLA_MACVLAN_MODE])
+
+ if (data && data[IFLA_MACVLAN_MODE]) {
+ if (vlan->mode == MACVLAN_MODE_SOURCE &&
+ vlan->mode != nla_get_u32(data[IFLA_MACVLAN_MODE]))
+ macvlan_flush_sources(vlan->port, vlan);
vlan->mode = nla_get_u32(data[IFLA_MACVLAN_MODE]);
+ }
+
+ if (data && data[IFLA_MACVLAN_MACADDR_MODE] &&
+ data[IFLA_MACVLAN_MACADDR]) {
+ if (vlan->mode == MACVLAN_MODE_SOURCE) {
+ if ((nla_get_u32(data[IFLA_MACVLAN_MACADDR_MODE]) ==
+ MACVLAN_MACADDR_ADD))
+ return macvlan_hash_add_sources(vlan,
+ nla_data(data[IFLA_MACVLAN_MACADDR]));
+
+ else if (nla_get_u32(data[IFLA_MACVLAN_MACADDR_MODE]) ==
+ MACVLAN_MACADDR_DEL) {
+ struct macvlan_source_list *list;
+
+ list = macvlan_hash_lookup_sources_list(vlan,
+ nla_data(data[IFLA_MACVLAN_MACADDR]));
+ if (list)
+ macvlan_hash_del_sources(list);
+ } else
+ return -EINVAL;
+ } else
+ return -EINVAL;
+ }
+
return 0;
}

static size_t macvlan_get_size(const struct net_device *dev)
{
- return nla_total_size(4);
+ struct macvlan_dev *vlan = netdev_priv(dev);
+ u16 source_size = 0;
+ int count = 0;
+
+ if (vlan->mode == MACVLAN_MODE_SOURCE) {
+ int i;
+ for (i = 0; i < MACVLAN_HASH_SIZE; i++) {
+ struct hlist_node *n;
+ struct macvlan_source_list *list;
+
+ hlist_for_each_entry_rcu(list, n,
+ &vlan->port->vlan_source_hash[i], hlist) {
+ if (list->vlan == vlan)
+ count++;
+ }
+ }
+ if (count)
+ source_size = nla_total_size(sizeof(struct nlattr))
+ + nla_total_size(sizeof(u8) * ETH_ALEN) * count;
+ }
+
+ return nla_total_size(4) + source_size;
+}
+
+static int macvlan_fill_nested(struct sk_buff *skb, const char *addr)
+{
+ NLA_PUT(skb, IFLA_MACVLAN_MACADDR, ETH_ALEN, addr);
+
+ return 0;
+
+nla_put_failure:
+ return -EMSGSIZE;
}

static int macvlan_fill_info(struct sk_buff *skb,
const struct net_device *dev)
{
struct macvlan_dev *vlan = netdev_priv(dev);
+ struct nlattr *adt;

NLA_PUT_U32(skb, IFLA_MACVLAN_MODE, vlan->mode);
+
+ if (vlan->mode == MACVLAN_MODE_SOURCE) {
+ int i;
+
+ adt = nla_nest_start(skb, IFLA_MACVLAN_MACADDR_DATA);
+ if (!adt)
+ goto nla_put_failure;
+
+ for (i = 0; i < MACVLAN_HASH_SIZE; i++) {
+ struct hlist_node *n;
+ struct macvlan_source_list *list;
+
+ hlist_for_each_entry_rcu(list, n,
+ &vlan->port->vlan_source_hash[i], hlist) {
+ if (list->vlan == vlan)
+ if (macvlan_fill_nested(skb,
+ list->addr))
+ goto nla_nested_failure;
+ }
+ }
+ nla_nest_end(skb, adt);
+ }
+
return 0;

+nla_nested_failure:
+ nla_nest_end(skb, adt);
+ return -EMSGSIZE;
+
nla_put_failure:
return -EMSGSIZE;
}

static const struct nla_policy macvlan_policy[IFLA_MACVLAN_MAX + 1] = {
[IFLA_MACVLAN_MODE] = { .type = NLA_U32 },
+ [IFLA_MACVLAN_MACADDR_MODE] = { .type = NLA_U32 },
+ [IFLA_MACVLAN_MACADDR] = { .type = NLA_BINARY, .len = MAX_ADDR_LEN },
+ [IFLA_MACVLAN_MACADDR_DATA] = { .type = NLA_NESTED },
};

int macvlan_link_register(struct rtnl_link_ops *ops)
diff -uprN -X linux/Documentation/dontdiff linux-3.2.1-orig/include/linux/if_link.h linux/include/linux/if_link.h
--- linux-3.2.1-orig/include/linux/if_link.h 2012-01-12 20:42:45.000000000 +0100
+++ linux/include/linux/if_link.h 2012-01-24 12:36:51.885312680 +0100
@@ -252,6 +252,9 @@ struct ifla_vlan_qos_mapping {
enum {
IFLA_MACVLAN_UNSPEC,
IFLA_MACVLAN_MODE,
+ IFLA_MACVLAN_MACADDR_MODE,
+ IFLA_MACVLAN_MACADDR,
+ IFLA_MACVLAN_MACADDR_DATA,
__IFLA_MACVLAN_MAX,
};

@@ -262,6 +265,12 @@ enum macvlan_mode {
MACVLAN_MODE_VEPA = 2, /* talk to other ports through ext bridge */
MACVLAN_MODE_BRIDGE = 4, /* talk to bridge ports directly */
MACVLAN_MODE_PASSTHRU = 8,/* take over the underlying device */
+ MACVLAN_MODE_SOURCE = 16,/* use source MAC address list to assign */
+};
+
+enum macvlan_macaddr_mode {
+ MACVLAN_MACADDR_ADD,
+ MACVLAN_MACADDR_DEL,
};

/* SR-IOV virtual function management section */
diff -uprN -X linux/Documentation/dontdiff linux-3.2.1-orig/net/core/rtnetlink.c linux/net/core/rtnetlink.c
--- linux-3.2.1-orig/net/core/rtnetlink.c 2012-01-12 20:42:45.000000000 +0100
+++ linux/net/core/rtnetlink.c 2012-01-24 14:26:58.083219352 +0100
@@ -1506,6 +1506,9 @@ errout:

if (send_addr_notify)
call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
+ min_ifinfo_dump_size = max_t(u16, if_nlmsg_size(dev),
+ min_ifinfo_dump_size);
+
return err;
}

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