1 files changed, 186 insertions, 20 deletions

diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index e4ec575c1fba..9f7aa448bd11 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -980,6 +980,19 @@ static size_t rtnl_xdp_size(void)
 	return xdp_size;
 }
 
+static size_t rtnl_prop_list_size(const struct net_device *dev)
+{
+	struct netdev_name_node *name_node;
+	size_t size;
+
+	if (list_empty(&dev->name_node->list))
+		return 0;
+	size = nla_total_size(0);
+	list_for_each_entry(name_node, &dev->name_node->list, list)
+		size += nla_total_size(ALTIFNAMSIZ);
+	return size;
+}
+
 static noinline size_t if_nlmsg_size(const struct net_device *dev,
 				     u32 ext_filter_mask)
 {
@@ -1027,6 +1040,7 @@ static noinline size_t if_nlmsg_size(const struct net_device *dev,
 	       + nla_total_size(4)  /* IFLA_CARRIER_DOWN_COUNT */
 	       + nla_total_size(4)  /* IFLA_MIN_MTU */
 	       + nla_total_size(4)  /* IFLA_MAX_MTU */
+	       + rtnl_prop_list_size(dev)
 	       + 0;
 }
 
@@ -1584,6 +1598,42 @@ static int rtnl_fill_link_af(struct sk_buff *skb,
 	return 0;
 }
 
+static int rtnl_fill_alt_ifnames(struct sk_buff *skb,
+				 const struct net_device *dev)
+{
+	struct netdev_name_node *name_node;
+	int count = 0;
+
+	list_for_each_entry(name_node, &dev->name_node->list, list) {
+		if (nla_put_string(skb, IFLA_ALT_IFNAME, name_node->name))
+			return -EMSGSIZE;
+		count++;
+	}
+	return count;
+}
+
+static int rtnl_fill_prop_list(struct sk_buff *skb,
+			       const struct net_device *dev)
+{
+	struct nlattr *prop_list;
+	int ret;
+
+	prop_list = nla_nest_start(skb, IFLA_PROP_LIST);
+	if (!prop_list)
+		return -EMSGSIZE;
+
+	ret = rtnl_fill_alt_ifnames(skb, dev);
+	if (ret <= 0)
+		goto nest_cancel;
+
+	nla_nest_end(skb, prop_list);
+	return 0;
+
+nest_cancel:
+	nla_nest_cancel(skb, prop_list);
+	return ret;
+}
+
 static int rtnl_fill_ifinfo(struct sk_buff *skb,
 			    struct net_device *dev, struct net *src_net,
 			    int type, u32 pid, u32 seq, u32 change,
@@ -1697,6 +1747,9 @@ static int rtnl_fill_ifinfo(struct sk_buff *skb,
 		goto nla_put_failure_rcu;
 	rcu_read_unlock();
 
+	if (rtnl_fill_prop_list(skb, dev))
+		goto nla_put_failure;
+
 	nlmsg_end(skb, nlh);
 	return 0;
 
@@ -1750,6 +1803,9 @@ static const struct nla_policy ifla_policy[IFLA_MAX+1] = {
 	[IFLA_CARRIER_DOWN_COUNT] = { .type = NLA_U32 },
 	[IFLA_MIN_MTU]		= { .type = NLA_U32 },
 	[IFLA_MAX_MTU]		= { .type = NLA_U32 },
+	[IFLA_PROP_LIST]	= { .type = NLA_NESTED },
+	[IFLA_ALT_IFNAME]	= { .type = NLA_STRING,
+				    .len = ALTIFNAMSIZ - 1 },
 };
 
 static const struct nla_policy ifla_info_policy[IFLA_INFO_MAX+1] = {
@@ -2744,6 +2800,26 @@ errout:
 	return err;
 }
 
+static struct net_device *rtnl_dev_get(struct net *net,
+				       struct nlattr *ifname_attr,
+				       struct nlattr *altifname_attr,
+				       char *ifname)
+{
+	char buffer[ALTIFNAMSIZ];
+
+	if (!ifname) {
+		ifname = buffer;
+		if (ifname_attr)
+			nla_strlcpy(ifname, ifname_attr, IFNAMSIZ);
+		else if (altifname_attr)
+			nla_strlcpy(ifname, altifname_attr, ALTIFNAMSIZ);
+		else
+			return NULL;
+	}
+
+	return __dev_get_by_name(net, ifname);
+}
+
 static int rtnl_setlink(struct sk_buff *skb, struct nlmsghdr *nlh,
 			struct netlink_ext_ack *extack)
 {
@@ -2772,8 +2848,8 @@ static int rtnl_setlink(struct sk_buff *skb, struct nlmsghdr *nlh,
 	ifm = nlmsg_data(nlh);
 	if (ifm->ifi_index > 0)
 		dev = __dev_get_by_index(net, ifm->ifi_index);
-	else if (tb[IFLA_IFNAME])
-		dev = __dev_get_by_name(net, ifname);
+	else if (tb[IFLA_IFNAME] || tb[IFLA_ALT_IFNAME])
+		dev = rtnl_dev_get(net, NULL, tb[IFLA_ALT_IFNAME], ifname);
 	else
 		goto errout;
 
@@ -2846,7 +2922,6 @@ static int rtnl_dellink(struct sk_buff *skb, struct nlmsghdr *nlh,
 	struct net *tgt_net = net;
 	struct net_device *dev = NULL;
 	struct ifinfomsg *ifm;
-	char ifname[IFNAMSIZ];
 	struct nlattr *tb[IFLA_MAX+1];
 	int err;
 	int netnsid = -1;
@@ -2860,9 +2935,6 @@ static int rtnl_dellink(struct sk_buff *skb, struct nlmsghdr *nlh,
 	if (err < 0)
 		return err;
 
-	if (tb[IFLA_IFNAME])
-		nla_strlcpy(ifname, tb[IFLA_IFNAME], IFNAMSIZ);
-
 	if (tb[IFLA_TARGET_NETNSID]) {
 		netnsid = nla_get_s32(tb[IFLA_TARGET_NETNSID]);
 		tgt_net = rtnl_get_net_ns_capable(NETLINK_CB(skb).sk, netnsid);
@@ -2874,8 +2946,9 @@ static int rtnl_dellink(struct sk_buff *skb, struct nlmsghdr *nlh,
 	ifm = nlmsg_data(nlh);
 	if (ifm->ifi_index > 0)
 		dev = __dev_get_by_index(tgt_net, ifm->ifi_index);
-	else if (tb[IFLA_IFNAME])
-		dev = __dev_get_by_name(tgt_net, ifname);
+	else if (tb[IFLA_IFNAME] || tb[IFLA_ALT_IFNAME])
+		dev = rtnl_dev_get(net, tb[IFLA_IFNAME],
+				   tb[IFLA_ALT_IFNAME], NULL);
 	else if (tb[IFLA_GROUP])
 		err = rtnl_group_dellink(tgt_net, nla_get_u32(tb[IFLA_GROUP]));
 	else
@@ -3046,12 +3119,10 @@ replay:
 	ifm = nlmsg_data(nlh);
 	if (ifm->ifi_index > 0)
 		dev = __dev_get_by_index(net, ifm->ifi_index);
-	else {
-		if (ifname[0])
-			dev = __dev_get_by_name(net, ifname);
-		else
-			dev = NULL;
-	}
+	else if (tb[IFLA_IFNAME] || tb[IFLA_ALT_IFNAME])
+		dev = rtnl_dev_get(net, NULL, tb[IFLA_ALT_IFNAME], ifname);
+	else
+		dev = NULL;
 
 	if (dev) {
 		master_dev = netdev_master_upper_dev_get(dev);
@@ -3313,6 +3384,7 @@ static int rtnl_valid_getlink_req(struct sk_buff *skb,
 
 		switch (i) {
 		case IFLA_IFNAME:
+		case IFLA_ALT_IFNAME:
 		case IFLA_EXT_MASK:
 		case IFLA_TARGET_NETNSID:
 			break;
@@ -3331,7 +3403,6 @@ static int rtnl_getlink(struct sk_buff *skb, struct nlmsghdr *nlh,
 	struct net *net = sock_net(skb->sk);
 	struct net *tgt_net = net;
 	struct ifinfomsg *ifm;
-	char ifname[IFNAMSIZ];
 	struct nlattr *tb[IFLA_MAX+1];
 	struct net_device *dev = NULL;
 	struct sk_buff *nskb;
@@ -3354,9 +3425,6 @@ static int rtnl_getlink(struct sk_buff *skb, struct nlmsghdr *nlh,
 			return PTR_ERR(tgt_net);
 	}
 
-	if (tb[IFLA_IFNAME])
-		nla_strlcpy(ifname, tb[IFLA_IFNAME], IFNAMSIZ);
-
 	if (tb[IFLA_EXT_MASK])
 		ext_filter_mask = nla_get_u32(tb[IFLA_EXT_MASK]);
 
@@ -3364,8 +3432,9 @@ static int rtnl_getlink(struct sk_buff *skb, struct nlmsghdr *nlh,
 	ifm = nlmsg_data(nlh);
 	if (ifm->ifi_index > 0)
 		dev = __dev_get_by_index(tgt_net, ifm->ifi_index);
-	else if (tb[IFLA_IFNAME])
-		dev = __dev_get_by_name(tgt_net, ifname);
+	else if (tb[IFLA_IFNAME] || tb[IFLA_ALT_IFNAME])
+		dev = rtnl_dev_get(tgt_net, tb[IFLA_IFNAME],
+				   tb[IFLA_ALT_IFNAME], NULL);
 	else
 		goto out;
 
@@ -3395,6 +3464,100 @@ out:
 	return err;
 }
 
+static int rtnl_alt_ifname(int cmd, struct net_device *dev, struct nlattr *attr,
+			   bool *changed, struct netlink_ext_ack *extack)
+{
+	char *alt_ifname;
+	int err;
+
+	err = nla_validate(attr, attr->nla_len, IFLA_MAX, ifla_policy, extack);
+	if (err)
+		return err;
+
+	alt_ifname = nla_data(attr);
+	if (cmd == RTM_NEWLINKPROP) {
+		alt_ifname = kstrdup(alt_ifname, GFP_KERNEL);
+		if (!alt_ifname)
+			return -ENOMEM;
+		err = netdev_name_node_alt_create(dev, alt_ifname);
+		if (err) {
+			kfree(alt_ifname);
+			return err;
+		}
+	} else if (cmd == RTM_DELLINKPROP) {
+		err = netdev_name_node_alt_destroy(dev, alt_ifname);
+		if (err)
+			return err;
+	} else {
+		WARN_ON(1);
+		return 0;
+	}
+
+	*changed = true;
+	return 0;
+}
+
+static int rtnl_linkprop(int cmd, struct sk_buff *skb, struct nlmsghdr *nlh,
+			 struct netlink_ext_ack *extack)
+{
+	struct net *net = sock_net(skb->sk);
+	struct nlattr *tb[IFLA_MAX + 1];
+	struct net_device *dev;
+	struct ifinfomsg *ifm;
+	bool changed = false;
+	struct nlattr *attr;
+	int err, rem;
+
+	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFLA_MAX, ifla_policy, extack);
+	if (err)
+		return err;
+
+	err = rtnl_ensure_unique_netns(tb, extack, true);
+	if (err)
+		return err;
+
+	ifm = nlmsg_data(nlh);
+	if (ifm->ifi_index > 0)
+		dev = __dev_get_by_index(net, ifm->ifi_index);
+	else if (tb[IFLA_IFNAME] || tb[IFLA_ALT_IFNAME])
+		dev = rtnl_dev_get(net, tb[IFLA_IFNAME],
+				   tb[IFLA_ALT_IFNAME], NULL);
+	else
+		return -EINVAL;
+
+	if (!dev)
+		return -ENODEV;
+
+	if (!tb[IFLA_PROP_LIST])
+		return 0;
+
+	nla_for_each_nested(attr, tb[IFLA_PROP_LIST], rem) {
+		switch (nla_type(attr)) {
+		case IFLA_ALT_IFNAME:
+			err = rtnl_alt_ifname(cmd, dev, attr, &changed, extack);
+			if (err)
+				return err;
+			break;
+		}
+	}
+
+	if (changed)
+		netdev_state_change(dev);
+	return 0;
+}
+
+static int rtnl_newlinkprop(struct sk_buff *skb, struct nlmsghdr *nlh,
+			    struct netlink_ext_ack *extack)
+{
+	return rtnl_linkprop(RTM_NEWLINKPROP, skb, nlh, extack);
+}
+
+static int rtnl_dellinkprop(struct sk_buff *skb, struct nlmsghdr *nlh,
+			    struct netlink_ext_ack *extack)
+{
+	return rtnl_linkprop(RTM_DELLINKPROP, skb, nlh, extack);
+}
+
 static u16 rtnl_calcit(struct sk_buff *skb, struct nlmsghdr *nlh)
 {
 	struct net *net = sock_net(skb->sk);
@@ -5353,6 +5516,9 @@ void __init rtnetlink_init(void)
 	rtnl_register(PF_UNSPEC, RTM_GETROUTE, NULL, rtnl_dump_all, 0);
 	rtnl_register(PF_UNSPEC, RTM_GETNETCONF, NULL, rtnl_dump_all, 0);
 
+	rtnl_register(PF_UNSPEC, RTM_NEWLINKPROP, rtnl_newlinkprop, NULL, 0);
+	rtnl_register(PF_UNSPEC, RTM_DELLINKPROP, rtnl_dellinkprop, NULL, 0);
+
 	rtnl_register(PF_BRIDGE, RTM_NEWNEIGH, rtnl_fdb_add, NULL, 0);
 	rtnl_register(PF_BRIDGE, RTM_DELNEIGH, rtnl_fdb_del, NULL, 0);
 	rtnl_register(PF_BRIDGE, RTM_GETNEIGH, rtnl_fdb_get, rtnl_fdb_dump, 0);