From: Jiri Pirko <j...@mellanox.com>
Add two commands to add and delete alternative ifnames for net device.
Each net device can have multiple alternative names.
Signed-off-by: Jiri Pirko <j...@mellanox.com>
---
include/linux/netdevice.h | 4 ++
include/uapi/linux/if.h | 1 +
include/uapi/linux/if_link.h | 1 +
include/uapi/linux/rtnetlink.h | 7 +++
net/core/dev.c | 58 ++++++++++++++++++-
net/core/rtnetlink.c | 102 +++++++++++++++++++++++++++++++++
security/selinux/nlmsgtab.c | 4 +-
7 files changed, 175 insertions(+), 2 deletions(-)
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 74f99f127b0e..6922fdb483ca 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -920,10 +920,14 @@ struct tlsdev_ops;
struct netdev_name_node {
struct hlist_node hlist;
+ struct list_head list;
struct net_device *dev;
char *name;
};
+int netdev_name_node_alt_create(struct net_device *dev, char *name);
+int netdev_name_node_alt_destroy(struct net_device *dev, char *name);
+
/*
* This structure defines the management hooks for network devices.
* The following hooks can be defined; unless noted otherwise, they are
diff --git a/include/uapi/linux/if.h b/include/uapi/linux/if.h
index 7fea0fd7d6f5..4bf33344aab1 100644
--- a/include/uapi/linux/if.h
+++ b/include/uapi/linux/if.h
@@ -33,6 +33,7 @@
#define IFNAMSIZ 16
#endif /* __UAPI_DEF_IF_IFNAMSIZ */
#define IFALIASZ 256
+#define ALTIFNAMSIZ 128
#include <linux/hdlc/ioctl.h>
/* For glibc compatibility. An empty enum does not compile. */
diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h
index 4a8c02cafa9a..92268946e04a 100644
--- a/include/uapi/linux/if_link.h
+++ b/include/uapi/linux/if_link.h
@@ -167,6 +167,7 @@ enum {
IFLA_NEW_IFINDEX,
IFLA_MIN_MTU,
IFLA_MAX_MTU,
+ IFLA_ALT_IFNAME_MOD, /* Alternative ifname to add/delete */
__IFLA_MAX
};
diff --git a/include/uapi/linux/rtnetlink.h b/include/uapi/linux/rtnetlink.h
index ce2a623abb75..b36cfd83eb76 100644
--- a/include/uapi/linux/rtnetlink.h
+++ b/include/uapi/linux/rtnetlink.h
@@ -164,6 +164,13 @@ enum {
RTM_GETNEXTHOP,
#define RTM_GETNEXTHOP RTM_GETNEXTHOP
+ RTM_NEWALTIFNAME = 108,
+#define RTM_NEWALTIFNAME RTM_NEWALTIFNAME
+ RTM_DELALTIFNAME,
+#define RTM_DELALTIFNAME RTM_DELALTIFNAME
+ RTM_GETALTIFNAME,
+#define RTM_GETALTIFNAME RTM_GETALTIFNAME
+
__RTM_MAX,
#define RTM_MAX (((__RTM_MAX + 3) & ~3) - 1)
};
diff --git a/net/core/dev.c b/net/core/dev.c
index ad0d42fbdeee..2a3be2b279d3 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -244,7 +244,13 @@ static struct netdev_name_node
*netdev_name_node_alloc(struct net_device *dev,
static struct netdev_name_node *
netdev_name_node_head_alloc(struct net_device *dev)
{
- return netdev_name_node_alloc(dev, dev->name);
+ struct netdev_name_node *name_node;
+
+ name_node = netdev_name_node_alloc(dev, dev->name);
+ if (!name_node)
+ return NULL;
+ INIT_LIST_HEAD(&name_node->list);
+ return name_node;
}
static void netdev_name_node_free(struct netdev_name_node *name_node)
@@ -288,6 +294,55 @@ static struct netdev_name_node
*netdev_name_node_lookup_rcu(struct net *net,
return NULL;
}
+int netdev_name_node_alt_create(struct net_device *dev, char *name)
+{
+ struct netdev_name_node *name_node;
+ struct net *net = dev_net(dev);
+
+ name_node = netdev_name_node_lookup(net, name);
+ if (name_node)
+ return -EEXIST;
+ name_node = netdev_name_node_alloc(dev, name);
+ if (!name_node)
+ return -ENOMEM;
+ netdev_name_node_add(net, name_node);
+ /* The node that holds dev->name acts as a head of per-device list. */
+ list_add_tail(&name_node->list, &dev->name_node->list);
+
+ return 0;
+}
+EXPORT_SYMBOL(netdev_name_node_alt_create);
+
+static void __netdev_name_node_alt_destroy(struct netdev_name_node *name_node)
+{
+ list_del(&name_node->list);
+ netdev_name_node_del(name_node);
+ kfree(name_node->name);
+ netdev_name_node_free(name_node);
+}
+
+int netdev_name_node_alt_destroy(struct net_device *dev, char *name)
+{
+ struct netdev_name_node *name_node;
+ struct net *net = dev_net(dev);
+
+ name_node = netdev_name_node_lookup(net, name);
+ if (!name_node)
+ return -ENOENT;
+ __netdev_name_node_alt_destroy(name_node);
+
+ return 0;
+}
+EXPORT_SYMBOL(netdev_name_node_alt_destroy);
+
+static void netdev_name_node_alt_flush(struct net_device *dev)
+{
+ struct netdev_name_node *name_node, *tmp;
+
+ list_for_each_entry_safe(name_node, tmp, &dev->name_node->list, list)
+ __netdev_name_node_alt_destroy(name_node);
+}
+
/* Device list insertion */
static void list_netdevice(struct net_device *dev)
{
@@ -8258,6 +8313,7 @@ static void rollback_registered_many(struct list_head
*head)
dev_uc_flush(dev);
dev_mc_flush(dev);
+ netdev_name_node_alt_flush(dev);
netdev_name_node_free(dev->name_node);
if (dev->netdev_ops->ndo_uninit)
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index 1ee6460f8275..7a2010b16e10 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -1750,6 +1750,8 @@ 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_ALT_IFNAME_MOD] = { .type = NLA_STRING,
+ .len = ALTIFNAMSIZ - 1 },
};
static const struct nla_policy ifla_info_policy[IFLA_INFO_MAX+1] = {
@@ -3373,6 +3375,103 @@ static int rtnl_getlink(struct sk_buff *skb, struct
nlmsghdr *nlh,
return err;
}
+static int rtnl_newaltifname(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;
+ char *new_alt_ifname;
+ int err;
+
+ 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]) {
+ char ifname[IFNAMSIZ];
+
+ nla_strlcpy(ifname, tb[IFLA_IFNAME], IFNAMSIZ);
+ dev = __dev_get_by_name(net, ifname);
+ } else {
+ return -EINVAL;
+ }
+
+ if (!dev)
+ return -ENODEV;
+
+ if (!tb[IFLA_ALT_IFNAME_MOD])
+ return -EINVAL;
+
+ new_alt_ifname = nla_strdup(tb[IFLA_ALT_IFNAME_MOD], GFP_KERNEL);
+ if (!new_alt_ifname)
+ return -ENOMEM;
+
+ err = netdev_name_node_alt_create(dev, new_alt_ifname);
+ if (err)
+ goto out_free_new_alt_ifname;
+
+ return 0;
+
+out_free_new_alt_ifname:
+ kfree(new_alt_ifname);
+ return err;
+}
+
+static int rtnl_delaltifname(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;
+ char *del_alt_ifname;
+ int err;
+
+ 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]) {
+ char ifname[IFNAMSIZ];
+
+ nla_strlcpy(ifname, tb[IFLA_IFNAME], IFNAMSIZ);
+ dev = __dev_get_by_name(net, ifname);
+ } else {
+ return -EINVAL;
+ }
+
+ if (!dev)
+ return -ENODEV;
+
+ if (!tb[IFLA_ALT_IFNAME_MOD])
+ return -EINVAL;
+
+ del_alt_ifname = nla_strdup(tb[IFLA_ALT_IFNAME_MOD], GFP_KERNEL);
+ if (!del_alt_ifname)
+ return -ENOMEM;
+
+ err = netdev_name_node_alt_destroy(dev, del_alt_ifname);
+ kfree(del_alt_ifname);
+
+ return err;
+}
+
static u16 rtnl_calcit(struct sk_buff *skb, struct nlmsghdr *nlh)
{
struct net *net = sock_net(skb->sk);
@@ -5331,6 +5430,9 @@ 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_NEWALTIFNAME, rtnl_newaltifname, NULL, 0);
+ rtnl_register(PF_UNSPEC, RTM_DELALTIFNAME, rtnl_delaltifname, 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);
diff --git a/security/selinux/nlmsgtab.c b/security/selinux/nlmsgtab.c
index 58345ba0528e..a712b54c666c 100644
--- a/security/selinux/nlmsgtab.c
+++ b/security/selinux/nlmsgtab.c
@@ -83,6 +83,8 @@ static const struct nlmsg_perm nlmsg_route_perms[] =
{ RTM_NEWNEXTHOP, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
{ RTM_DELNEXTHOP, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
{ RTM_GETNEXTHOP, NETLINK_ROUTE_SOCKET__NLMSG_READ },
+ { RTM_NEWALTIFNAME, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
+ { RTM_DELALTIFNAME, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
};
static const struct nlmsg_perm nlmsg_tcpdiag_perms[] =
@@ -166,7 +168,7 @@ int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32
*perm)
* structures at the top of this file with the new mappings
* before updating the BUILD_BUG_ON() macro!
*/
- BUILD_BUG_ON(RTM_MAX != (RTM_NEWNEXTHOP + 3));
+ BUILD_BUG_ON(RTM_MAX != (RTM_NEWALTIFNAME + 3));
err = nlmsg_perm(nlmsg_type, perm, nlmsg_route_perms,
sizeof(nlmsg_route_perms));
break;
--
2.21.0
