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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /drivers/net/vrf.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/net/vrf.c')
-rw-r--r--drivers/net/vrf.c2053
1 files changed, 2053 insertions, 0 deletions
diff --git a/drivers/net/vrf.c b/drivers/net/vrf.c
new file mode 100644
index 0000000000..b90dccdc2d
--- /dev/null
+++ b/drivers/net/vrf.c
@@ -0,0 +1,2053 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * vrf.c: device driver to encapsulate a VRF space
+ *
+ * Copyright (c) 2015 Cumulus Networks. All rights reserved.
+ * Copyright (c) 2015 Shrijeet Mukherjee <shm@cumulusnetworks.com>
+ * Copyright (c) 2015 David Ahern <dsa@cumulusnetworks.com>
+ *
+ * Based on dummy, team and ipvlan drivers
+ */
+
+#include <linux/ethtool.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/ip.h>
+#include <linux/init.h>
+#include <linux/moduleparam.h>
+#include <linux/netfilter.h>
+#include <linux/rtnetlink.h>
+#include <net/rtnetlink.h>
+#include <linux/u64_stats_sync.h>
+#include <linux/hashtable.h>
+#include <linux/spinlock_types.h>
+
+#include <linux/inetdevice.h>
+#include <net/arp.h>
+#include <net/ip.h>
+#include <net/ip_fib.h>
+#include <net/ip6_fib.h>
+#include <net/ip6_route.h>
+#include <net/route.h>
+#include <net/addrconf.h>
+#include <net/l3mdev.h>
+#include <net/fib_rules.h>
+#include <net/sch_generic.h>
+#include <net/netns/generic.h>
+#include <net/netfilter/nf_conntrack.h>
+
+#define DRV_NAME "vrf"
+#define DRV_VERSION "1.1"
+
+#define FIB_RULE_PREF 1000 /* default preference for FIB rules */
+
+#define HT_MAP_BITS 4
+#define HASH_INITVAL ((u32)0xcafef00d)
+
+struct vrf_map {
+ DECLARE_HASHTABLE(ht, HT_MAP_BITS);
+ spinlock_t vmap_lock;
+
+ /* shared_tables:
+ * count how many distinct tables do not comply with the strict mode
+ * requirement.
+ * shared_tables value must be 0 in order to enable the strict mode.
+ *
+ * example of the evolution of shared_tables:
+ * | time
+ * add vrf0 --> table 100 shared_tables = 0 | t0
+ * add vrf1 --> table 101 shared_tables = 0 | t1
+ * add vrf2 --> table 100 shared_tables = 1 | t2
+ * add vrf3 --> table 100 shared_tables = 1 | t3
+ * add vrf4 --> table 101 shared_tables = 2 v t4
+ *
+ * shared_tables is a "step function" (or "staircase function")
+ * and it is increased by one when the second vrf is associated to a
+ * table.
+ *
+ * at t2, vrf0 and vrf2 are bound to table 100: shared_tables = 1.
+ *
+ * at t3, another dev (vrf3) is bound to the same table 100 but the
+ * value of shared_tables is still 1.
+ * This means that no matter how many new vrfs will register on the
+ * table 100, the shared_tables will not increase (considering only
+ * table 100).
+ *
+ * at t4, vrf4 is bound to table 101, and shared_tables = 2.
+ *
+ * Looking at the value of shared_tables we can immediately know if
+ * the strict_mode can or cannot be enforced. Indeed, strict_mode
+ * can be enforced iff shared_tables = 0.
+ *
+ * Conversely, shared_tables is decreased when a vrf is de-associated
+ * from a table with exactly two associated vrfs.
+ */
+ u32 shared_tables;
+
+ bool strict_mode;
+};
+
+struct vrf_map_elem {
+ struct hlist_node hnode;
+ struct list_head vrf_list; /* VRFs registered to this table */
+
+ u32 table_id;
+ int users;
+ int ifindex;
+};
+
+static unsigned int vrf_net_id;
+
+/* per netns vrf data */
+struct netns_vrf {
+ /* protected by rtnl lock */
+ bool add_fib_rules;
+
+ struct vrf_map vmap;
+ struct ctl_table_header *ctl_hdr;
+};
+
+struct net_vrf {
+ struct rtable __rcu *rth;
+ struct rt6_info __rcu *rt6;
+#if IS_ENABLED(CONFIG_IPV6)
+ struct fib6_table *fib6_table;
+#endif
+ u32 tb_id;
+
+ struct list_head me_list; /* entry in vrf_map_elem */
+ int ifindex;
+};
+
+static void vrf_rx_stats(struct net_device *dev, int len)
+{
+ struct pcpu_dstats *dstats = this_cpu_ptr(dev->dstats);
+
+ u64_stats_update_begin(&dstats->syncp);
+ dstats->rx_packets++;
+ dstats->rx_bytes += len;
+ u64_stats_update_end(&dstats->syncp);
+}
+
+static void vrf_tx_error(struct net_device *vrf_dev, struct sk_buff *skb)
+{
+ vrf_dev->stats.tx_errors++;
+ kfree_skb(skb);
+}
+
+static void vrf_get_stats64(struct net_device *dev,
+ struct rtnl_link_stats64 *stats)
+{
+ int i;
+
+ for_each_possible_cpu(i) {
+ const struct pcpu_dstats *dstats;
+ u64 tbytes, tpkts, tdrops, rbytes, rpkts;
+ unsigned int start;
+
+ dstats = per_cpu_ptr(dev->dstats, i);
+ do {
+ start = u64_stats_fetch_begin(&dstats->syncp);
+ tbytes = dstats->tx_bytes;
+ tpkts = dstats->tx_packets;
+ tdrops = dstats->tx_drops;
+ rbytes = dstats->rx_bytes;
+ rpkts = dstats->rx_packets;
+ } while (u64_stats_fetch_retry(&dstats->syncp, start));
+ stats->tx_bytes += tbytes;
+ stats->tx_packets += tpkts;
+ stats->tx_dropped += tdrops;
+ stats->rx_bytes += rbytes;
+ stats->rx_packets += rpkts;
+ }
+}
+
+static struct vrf_map *netns_vrf_map(struct net *net)
+{
+ struct netns_vrf *nn_vrf = net_generic(net, vrf_net_id);
+
+ return &nn_vrf->vmap;
+}
+
+static struct vrf_map *netns_vrf_map_by_dev(struct net_device *dev)
+{
+ return netns_vrf_map(dev_net(dev));
+}
+
+static int vrf_map_elem_get_vrf_ifindex(struct vrf_map_elem *me)
+{
+ struct list_head *me_head = &me->vrf_list;
+ struct net_vrf *vrf;
+
+ if (list_empty(me_head))
+ return -ENODEV;
+
+ vrf = list_first_entry(me_head, struct net_vrf, me_list);
+
+ return vrf->ifindex;
+}
+
+static struct vrf_map_elem *vrf_map_elem_alloc(gfp_t flags)
+{
+ struct vrf_map_elem *me;
+
+ me = kmalloc(sizeof(*me), flags);
+ if (!me)
+ return NULL;
+
+ return me;
+}
+
+static void vrf_map_elem_free(struct vrf_map_elem *me)
+{
+ kfree(me);
+}
+
+static void vrf_map_elem_init(struct vrf_map_elem *me, int table_id,
+ int ifindex, int users)
+{
+ me->table_id = table_id;
+ me->ifindex = ifindex;
+ me->users = users;
+ INIT_LIST_HEAD(&me->vrf_list);
+}
+
+static struct vrf_map_elem *vrf_map_lookup_elem(struct vrf_map *vmap,
+ u32 table_id)
+{
+ struct vrf_map_elem *me;
+ u32 key;
+
+ key = jhash_1word(table_id, HASH_INITVAL);
+ hash_for_each_possible(vmap->ht, me, hnode, key) {
+ if (me->table_id == table_id)
+ return me;
+ }
+
+ return NULL;
+}
+
+static void vrf_map_add_elem(struct vrf_map *vmap, struct vrf_map_elem *me)
+{
+ u32 table_id = me->table_id;
+ u32 key;
+
+ key = jhash_1word(table_id, HASH_INITVAL);
+ hash_add(vmap->ht, &me->hnode, key);
+}
+
+static void vrf_map_del_elem(struct vrf_map_elem *me)
+{
+ hash_del(&me->hnode);
+}
+
+static void vrf_map_lock(struct vrf_map *vmap) __acquires(&vmap->vmap_lock)
+{
+ spin_lock(&vmap->vmap_lock);
+}
+
+static void vrf_map_unlock(struct vrf_map *vmap) __releases(&vmap->vmap_lock)
+{
+ spin_unlock(&vmap->vmap_lock);
+}
+
+/* called with rtnl lock held */
+static int
+vrf_map_register_dev(struct net_device *dev, struct netlink_ext_ack *extack)
+{
+ struct vrf_map *vmap = netns_vrf_map_by_dev(dev);
+ struct net_vrf *vrf = netdev_priv(dev);
+ struct vrf_map_elem *new_me, *me;
+ u32 table_id = vrf->tb_id;
+ bool free_new_me = false;
+ int users;
+ int res;
+
+ /* we pre-allocate elements used in the spin-locked section (so that we
+ * keep the spinlock as short as possible).
+ */
+ new_me = vrf_map_elem_alloc(GFP_KERNEL);
+ if (!new_me)
+ return -ENOMEM;
+
+ vrf_map_elem_init(new_me, table_id, dev->ifindex, 0);
+
+ vrf_map_lock(vmap);
+
+ me = vrf_map_lookup_elem(vmap, table_id);
+ if (!me) {
+ me = new_me;
+ vrf_map_add_elem(vmap, me);
+ goto link_vrf;
+ }
+
+ /* we already have an entry in the vrf_map, so it means there is (at
+ * least) a vrf registered on the specific table.
+ */
+ free_new_me = true;
+ if (vmap->strict_mode) {
+ /* vrfs cannot share the same table */
+ NL_SET_ERR_MSG(extack, "Table is used by another VRF");
+ res = -EBUSY;
+ goto unlock;
+ }
+
+link_vrf:
+ users = ++me->users;
+ if (users == 2)
+ ++vmap->shared_tables;
+
+ list_add(&vrf->me_list, &me->vrf_list);
+
+ res = 0;
+
+unlock:
+ vrf_map_unlock(vmap);
+
+ /* clean-up, if needed */
+ if (free_new_me)
+ vrf_map_elem_free(new_me);
+
+ return res;
+}
+
+/* called with rtnl lock held */
+static void vrf_map_unregister_dev(struct net_device *dev)
+{
+ struct vrf_map *vmap = netns_vrf_map_by_dev(dev);
+ struct net_vrf *vrf = netdev_priv(dev);
+ u32 table_id = vrf->tb_id;
+ struct vrf_map_elem *me;
+ int users;
+
+ vrf_map_lock(vmap);
+
+ me = vrf_map_lookup_elem(vmap, table_id);
+ if (!me)
+ goto unlock;
+
+ list_del(&vrf->me_list);
+
+ users = --me->users;
+ if (users == 1) {
+ --vmap->shared_tables;
+ } else if (users == 0) {
+ vrf_map_del_elem(me);
+
+ /* no one will refer to this element anymore */
+ vrf_map_elem_free(me);
+ }
+
+unlock:
+ vrf_map_unlock(vmap);
+}
+
+/* return the vrf device index associated with the table_id */
+static int vrf_ifindex_lookup_by_table_id(struct net *net, u32 table_id)
+{
+ struct vrf_map *vmap = netns_vrf_map(net);
+ struct vrf_map_elem *me;
+ int ifindex;
+
+ vrf_map_lock(vmap);
+
+ if (!vmap->strict_mode) {
+ ifindex = -EPERM;
+ goto unlock;
+ }
+
+ me = vrf_map_lookup_elem(vmap, table_id);
+ if (!me) {
+ ifindex = -ENODEV;
+ goto unlock;
+ }
+
+ ifindex = vrf_map_elem_get_vrf_ifindex(me);
+
+unlock:
+ vrf_map_unlock(vmap);
+
+ return ifindex;
+}
+
+/* by default VRF devices do not have a qdisc and are expected
+ * to be created with only a single queue.
+ */
+static bool qdisc_tx_is_default(const struct net_device *dev)
+{
+ struct netdev_queue *txq;
+ struct Qdisc *qdisc;
+
+ if (dev->num_tx_queues > 1)
+ return false;
+
+ txq = netdev_get_tx_queue(dev, 0);
+ qdisc = rcu_access_pointer(txq->qdisc);
+
+ return !qdisc->enqueue;
+}
+
+/* Local traffic destined to local address. Reinsert the packet to rx
+ * path, similar to loopback handling.
+ */
+static int vrf_local_xmit(struct sk_buff *skb, struct net_device *dev,
+ struct dst_entry *dst)
+{
+ int len = skb->len;
+
+ skb_orphan(skb);
+
+ skb_dst_set(skb, dst);
+
+ /* set pkt_type to avoid skb hitting packet taps twice -
+ * once on Tx and again in Rx processing
+ */
+ skb->pkt_type = PACKET_LOOPBACK;
+
+ skb->protocol = eth_type_trans(skb, dev);
+
+ if (likely(__netif_rx(skb) == NET_RX_SUCCESS))
+ vrf_rx_stats(dev, len);
+ else
+ this_cpu_inc(dev->dstats->rx_drops);
+
+ return NETDEV_TX_OK;
+}
+
+static void vrf_nf_set_untracked(struct sk_buff *skb)
+{
+ if (skb_get_nfct(skb) == 0)
+ nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
+}
+
+static void vrf_nf_reset_ct(struct sk_buff *skb)
+{
+ if (skb_get_nfct(skb) == IP_CT_UNTRACKED)
+ nf_reset_ct(skb);
+}
+
+#if IS_ENABLED(CONFIG_IPV6)
+static int vrf_ip6_local_out(struct net *net, struct sock *sk,
+ struct sk_buff *skb)
+{
+ int err;
+
+ vrf_nf_reset_ct(skb);
+
+ err = nf_hook(NFPROTO_IPV6, NF_INET_LOCAL_OUT, net,
+ sk, skb, NULL, skb_dst(skb)->dev, dst_output);
+
+ if (likely(err == 1))
+ err = dst_output(net, sk, skb);
+
+ return err;
+}
+
+static netdev_tx_t vrf_process_v6_outbound(struct sk_buff *skb,
+ struct net_device *dev)
+{
+ const struct ipv6hdr *iph;
+ struct net *net = dev_net(skb->dev);
+ struct flowi6 fl6;
+ int ret = NET_XMIT_DROP;
+ struct dst_entry *dst;
+ struct dst_entry *dst_null = &net->ipv6.ip6_null_entry->dst;
+
+ if (!pskb_may_pull(skb, ETH_HLEN + sizeof(struct ipv6hdr)))
+ goto err;
+
+ iph = ipv6_hdr(skb);
+
+ memset(&fl6, 0, sizeof(fl6));
+ /* needed to match OIF rule */
+ fl6.flowi6_l3mdev = dev->ifindex;
+ fl6.flowi6_iif = LOOPBACK_IFINDEX;
+ fl6.daddr = iph->daddr;
+ fl6.saddr = iph->saddr;
+ fl6.flowlabel = ip6_flowinfo(iph);
+ fl6.flowi6_mark = skb->mark;
+ fl6.flowi6_proto = iph->nexthdr;
+
+ dst = ip6_dst_lookup_flow(net, NULL, &fl6, NULL);
+ if (IS_ERR(dst) || dst == dst_null)
+ goto err;
+
+ skb_dst_drop(skb);
+
+ /* if dst.dev is the VRF device again this is locally originated traffic
+ * destined to a local address. Short circuit to Rx path.
+ */
+ if (dst->dev == dev)
+ return vrf_local_xmit(skb, dev, dst);
+
+ skb_dst_set(skb, dst);
+
+ /* strip the ethernet header added for pass through VRF device */
+ __skb_pull(skb, skb_network_offset(skb));
+
+ memset(IP6CB(skb), 0, sizeof(*IP6CB(skb)));
+ ret = vrf_ip6_local_out(net, skb->sk, skb);
+ if (unlikely(net_xmit_eval(ret)))
+ dev->stats.tx_errors++;
+ else
+ ret = NET_XMIT_SUCCESS;
+
+ return ret;
+err:
+ vrf_tx_error(dev, skb);
+ return NET_XMIT_DROP;
+}
+#else
+static netdev_tx_t vrf_process_v6_outbound(struct sk_buff *skb,
+ struct net_device *dev)
+{
+ vrf_tx_error(dev, skb);
+ return NET_XMIT_DROP;
+}
+#endif
+
+/* based on ip_local_out; can't use it b/c the dst is switched pointing to us */
+static int vrf_ip_local_out(struct net *net, struct sock *sk,
+ struct sk_buff *skb)
+{
+ int err;
+
+ vrf_nf_reset_ct(skb);
+
+ err = nf_hook(NFPROTO_IPV4, NF_INET_LOCAL_OUT, net, sk,
+ skb, NULL, skb_dst(skb)->dev, dst_output);
+ if (likely(err == 1))
+ err = dst_output(net, sk, skb);
+
+ return err;
+}
+
+static netdev_tx_t vrf_process_v4_outbound(struct sk_buff *skb,
+ struct net_device *vrf_dev)
+{
+ struct iphdr *ip4h;
+ int ret = NET_XMIT_DROP;
+ struct flowi4 fl4;
+ struct net *net = dev_net(vrf_dev);
+ struct rtable *rt;
+
+ if (!pskb_may_pull(skb, ETH_HLEN + sizeof(struct iphdr)))
+ goto err;
+
+ ip4h = ip_hdr(skb);
+
+ memset(&fl4, 0, sizeof(fl4));
+ /* needed to match OIF rule */
+ fl4.flowi4_l3mdev = vrf_dev->ifindex;
+ fl4.flowi4_iif = LOOPBACK_IFINDEX;
+ fl4.flowi4_tos = RT_TOS(ip4h->tos);
+ fl4.flowi4_flags = FLOWI_FLAG_ANYSRC;
+ fl4.flowi4_proto = ip4h->protocol;
+ fl4.daddr = ip4h->daddr;
+ fl4.saddr = ip4h->saddr;
+
+ rt = ip_route_output_flow(net, &fl4, NULL);
+ if (IS_ERR(rt))
+ goto err;
+
+ skb_dst_drop(skb);
+
+ /* if dst.dev is the VRF device again this is locally originated traffic
+ * destined to a local address. Short circuit to Rx path.
+ */
+ if (rt->dst.dev == vrf_dev)
+ return vrf_local_xmit(skb, vrf_dev, &rt->dst);
+
+ skb_dst_set(skb, &rt->dst);
+
+ /* strip the ethernet header added for pass through VRF device */
+ __skb_pull(skb, skb_network_offset(skb));
+
+ if (!ip4h->saddr) {
+ ip4h->saddr = inet_select_addr(skb_dst(skb)->dev, 0,
+ RT_SCOPE_LINK);
+ }
+
+ memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
+ ret = vrf_ip_local_out(dev_net(skb_dst(skb)->dev), skb->sk, skb);
+ if (unlikely(net_xmit_eval(ret)))
+ vrf_dev->stats.tx_errors++;
+ else
+ ret = NET_XMIT_SUCCESS;
+
+out:
+ return ret;
+err:
+ vrf_tx_error(vrf_dev, skb);
+ goto out;
+}
+
+static netdev_tx_t is_ip_tx_frame(struct sk_buff *skb, struct net_device *dev)
+{
+ switch (skb->protocol) {
+ case htons(ETH_P_IP):
+ return vrf_process_v4_outbound(skb, dev);
+ case htons(ETH_P_IPV6):
+ return vrf_process_v6_outbound(skb, dev);
+ default:
+ vrf_tx_error(dev, skb);
+ return NET_XMIT_DROP;
+ }
+}
+
+static netdev_tx_t vrf_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+ int len = skb->len;
+ netdev_tx_t ret = is_ip_tx_frame(skb, dev);
+
+ if (likely(ret == NET_XMIT_SUCCESS || ret == NET_XMIT_CN)) {
+ struct pcpu_dstats *dstats = this_cpu_ptr(dev->dstats);
+
+ u64_stats_update_begin(&dstats->syncp);
+ dstats->tx_packets++;
+ dstats->tx_bytes += len;
+ u64_stats_update_end(&dstats->syncp);
+ } else {
+ this_cpu_inc(dev->dstats->tx_drops);
+ }
+
+ return ret;
+}
+
+static void vrf_finish_direct(struct sk_buff *skb)
+{
+ struct net_device *vrf_dev = skb->dev;
+
+ if (!list_empty(&vrf_dev->ptype_all) &&
+ likely(skb_headroom(skb) >= ETH_HLEN)) {
+ struct ethhdr *eth = skb_push(skb, ETH_HLEN);
+
+ ether_addr_copy(eth->h_source, vrf_dev->dev_addr);
+ eth_zero_addr(eth->h_dest);
+ eth->h_proto = skb->protocol;
+
+ dev_queue_xmit_nit(skb, vrf_dev);
+
+ skb_pull(skb, ETH_HLEN);
+ }
+
+ vrf_nf_reset_ct(skb);
+}
+
+#if IS_ENABLED(CONFIG_IPV6)
+/* modelled after ip6_finish_output2 */
+static int vrf_finish_output6(struct net *net, struct sock *sk,
+ struct sk_buff *skb)
+{
+ struct dst_entry *dst = skb_dst(skb);
+ struct net_device *dev = dst->dev;
+ const struct in6_addr *nexthop;
+ struct neighbour *neigh;
+ int ret;
+
+ vrf_nf_reset_ct(skb);
+
+ skb->protocol = htons(ETH_P_IPV6);
+ skb->dev = dev;
+
+ rcu_read_lock();
+ nexthop = rt6_nexthop((struct rt6_info *)dst, &ipv6_hdr(skb)->daddr);
+ neigh = __ipv6_neigh_lookup_noref(dst->dev, nexthop);
+ if (unlikely(!neigh))
+ neigh = __neigh_create(&nd_tbl, nexthop, dst->dev, false);
+ if (!IS_ERR(neigh)) {
+ sock_confirm_neigh(skb, neigh);
+ ret = neigh_output(neigh, skb, false);
+ rcu_read_unlock();
+ return ret;
+ }
+ rcu_read_unlock();
+
+ IP6_INC_STATS(dev_net(dst->dev),
+ ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES);
+ kfree_skb(skb);
+ return -EINVAL;
+}
+
+/* modelled after ip6_output */
+static int vrf_output6(struct net *net, struct sock *sk, struct sk_buff *skb)
+{
+ return NF_HOOK_COND(NFPROTO_IPV6, NF_INET_POST_ROUTING,
+ net, sk, skb, NULL, skb_dst(skb)->dev,
+ vrf_finish_output6,
+ !(IP6CB(skb)->flags & IP6SKB_REROUTED));
+}
+
+/* set dst on skb to send packet to us via dev_xmit path. Allows
+ * packet to go through device based features such as qdisc, netfilter
+ * hooks and packet sockets with skb->dev set to vrf device.
+ */
+static struct sk_buff *vrf_ip6_out_redirect(struct net_device *vrf_dev,
+ struct sk_buff *skb)
+{
+ struct net_vrf *vrf = netdev_priv(vrf_dev);
+ struct dst_entry *dst = NULL;
+ struct rt6_info *rt6;
+
+ rcu_read_lock();
+
+ rt6 = rcu_dereference(vrf->rt6);
+ if (likely(rt6)) {
+ dst = &rt6->dst;
+ dst_hold(dst);
+ }
+
+ rcu_read_unlock();
+
+ if (unlikely(!dst)) {
+ vrf_tx_error(vrf_dev, skb);
+ return NULL;
+ }
+
+ skb_dst_drop(skb);
+ skb_dst_set(skb, dst);
+
+ return skb;
+}
+
+static int vrf_output6_direct_finish(struct net *net, struct sock *sk,
+ struct sk_buff *skb)
+{
+ vrf_finish_direct(skb);
+
+ return vrf_ip6_local_out(net, sk, skb);
+}
+
+static int vrf_output6_direct(struct net *net, struct sock *sk,
+ struct sk_buff *skb)
+{
+ int err = 1;
+
+ skb->protocol = htons(ETH_P_IPV6);
+
+ if (!(IPCB(skb)->flags & IPSKB_REROUTED))
+ err = nf_hook(NFPROTO_IPV6, NF_INET_POST_ROUTING, net, sk, skb,
+ NULL, skb->dev, vrf_output6_direct_finish);
+
+ if (likely(err == 1))
+ vrf_finish_direct(skb);
+
+ return err;
+}
+
+static int vrf_ip6_out_direct_finish(struct net *net, struct sock *sk,
+ struct sk_buff *skb)
+{
+ int err;
+
+ err = vrf_output6_direct(net, sk, skb);
+ if (likely(err == 1))
+ err = vrf_ip6_local_out(net, sk, skb);
+
+ return err;
+}
+
+static struct sk_buff *vrf_ip6_out_direct(struct net_device *vrf_dev,
+ struct sock *sk,
+ struct sk_buff *skb)
+{
+ struct net *net = dev_net(vrf_dev);
+ int err;
+
+ skb->dev = vrf_dev;
+
+ err = nf_hook(NFPROTO_IPV6, NF_INET_LOCAL_OUT, net, sk,
+ skb, NULL, vrf_dev, vrf_ip6_out_direct_finish);
+
+ if (likely(err == 1))
+ err = vrf_output6_direct(net, sk, skb);
+
+ if (likely(err == 1))
+ return skb;
+
+ return NULL;
+}
+
+static struct sk_buff *vrf_ip6_out(struct net_device *vrf_dev,
+ struct sock *sk,
+ struct sk_buff *skb)
+{
+ /* don't divert link scope packets */
+ if (rt6_need_strict(&ipv6_hdr(skb)->daddr))
+ return skb;
+
+ vrf_nf_set_untracked(skb);
+
+ if (qdisc_tx_is_default(vrf_dev) ||
+ IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
+ return vrf_ip6_out_direct(vrf_dev, sk, skb);
+
+ return vrf_ip6_out_redirect(vrf_dev, skb);
+}
+
+/* holding rtnl */
+static void vrf_rt6_release(struct net_device *dev, struct net_vrf *vrf)
+{
+ struct rt6_info *rt6 = rtnl_dereference(vrf->rt6);
+ struct net *net = dev_net(dev);
+ struct dst_entry *dst;
+
+ RCU_INIT_POINTER(vrf->rt6, NULL);
+ synchronize_rcu();
+
+ /* move dev in dst's to loopback so this VRF device can be deleted
+ * - based on dst_ifdown
+ */
+ if (rt6) {
+ dst = &rt6->dst;
+ netdev_ref_replace(dst->dev, net->loopback_dev,
+ &dst->dev_tracker, GFP_KERNEL);
+ dst->dev = net->loopback_dev;
+ dst_release(dst);
+ }
+}
+
+static int vrf_rt6_create(struct net_device *dev)
+{
+ int flags = DST_NOPOLICY | DST_NOXFRM;
+ struct net_vrf *vrf = netdev_priv(dev);
+ struct net *net = dev_net(dev);
+ struct rt6_info *rt6;
+ int rc = -ENOMEM;
+
+ /* IPv6 can be CONFIG enabled and then disabled runtime */
+ if (!ipv6_mod_enabled())
+ return 0;
+
+ vrf->fib6_table = fib6_new_table(net, vrf->tb_id);
+ if (!vrf->fib6_table)
+ goto out;
+
+ /* create a dst for routing packets out a VRF device */
+ rt6 = ip6_dst_alloc(net, dev, flags);
+ if (!rt6)
+ goto out;
+
+ rt6->dst.output = vrf_output6;
+
+ rcu_assign_pointer(vrf->rt6, rt6);
+
+ rc = 0;
+out:
+ return rc;
+}
+#else
+static struct sk_buff *vrf_ip6_out(struct net_device *vrf_dev,
+ struct sock *sk,
+ struct sk_buff *skb)
+{
+ return skb;
+}
+
+static void vrf_rt6_release(struct net_device *dev, struct net_vrf *vrf)
+{
+}
+
+static int vrf_rt6_create(struct net_device *dev)
+{
+ return 0;
+}
+#endif
+
+/* modelled after ip_finish_output2 */
+static int vrf_finish_output(struct net *net, struct sock *sk, struct sk_buff *skb)
+{
+ struct dst_entry *dst = skb_dst(skb);
+ struct rtable *rt = (struct rtable *)dst;
+ struct net_device *dev = dst->dev;
+ unsigned int hh_len = LL_RESERVED_SPACE(dev);
+ struct neighbour *neigh;
+ bool is_v6gw = false;
+
+ vrf_nf_reset_ct(skb);
+
+ /* Be paranoid, rather than too clever. */
+ if (unlikely(skb_headroom(skb) < hh_len && dev->header_ops)) {
+ skb = skb_expand_head(skb, hh_len);
+ if (!skb) {
+ dev->stats.tx_errors++;
+ return -ENOMEM;
+ }
+ }
+
+ rcu_read_lock();
+
+ neigh = ip_neigh_for_gw(rt, skb, &is_v6gw);
+ if (!IS_ERR(neigh)) {
+ int ret;
+
+ sock_confirm_neigh(skb, neigh);
+ /* if crossing protocols, can not use the cached header */
+ ret = neigh_output(neigh, skb, is_v6gw);
+ rcu_read_unlock();
+ return ret;
+ }
+
+ rcu_read_unlock();
+ vrf_tx_error(skb->dev, skb);
+ return -EINVAL;
+}
+
+static int vrf_output(struct net *net, struct sock *sk, struct sk_buff *skb)
+{
+ struct net_device *dev = skb_dst(skb)->dev;
+
+ IP_UPD_PO_STATS(net, IPSTATS_MIB_OUT, skb->len);
+
+ skb->dev = dev;
+ skb->protocol = htons(ETH_P_IP);
+
+ return NF_HOOK_COND(NFPROTO_IPV4, NF_INET_POST_ROUTING,
+ net, sk, skb, NULL, dev,
+ vrf_finish_output,
+ !(IPCB(skb)->flags & IPSKB_REROUTED));
+}
+
+/* set dst on skb to send packet to us via dev_xmit path. Allows
+ * packet to go through device based features such as qdisc, netfilter
+ * hooks and packet sockets with skb->dev set to vrf device.
+ */
+static struct sk_buff *vrf_ip_out_redirect(struct net_device *vrf_dev,
+ struct sk_buff *skb)
+{
+ struct net_vrf *vrf = netdev_priv(vrf_dev);
+ struct dst_entry *dst = NULL;
+ struct rtable *rth;
+
+ rcu_read_lock();
+
+ rth = rcu_dereference(vrf->rth);
+ if (likely(rth)) {
+ dst = &rth->dst;
+ dst_hold(dst);
+ }
+
+ rcu_read_unlock();
+
+ if (unlikely(!dst)) {
+ vrf_tx_error(vrf_dev, skb);
+ return NULL;
+ }
+
+ skb_dst_drop(skb);
+ skb_dst_set(skb, dst);
+
+ return skb;
+}
+
+static int vrf_output_direct_finish(struct net *net, struct sock *sk,
+ struct sk_buff *skb)
+{
+ vrf_finish_direct(skb);
+
+ return vrf_ip_local_out(net, sk, skb);
+}
+
+static int vrf_output_direct(struct net *net, struct sock *sk,
+ struct sk_buff *skb)
+{
+ int err = 1;
+
+ skb->protocol = htons(ETH_P_IP);
+
+ if (!(IPCB(skb)->flags & IPSKB_REROUTED))
+ err = nf_hook(NFPROTO_IPV4, NF_INET_POST_ROUTING, net, sk, skb,
+ NULL, skb->dev, vrf_output_direct_finish);
+
+ if (likely(err == 1))
+ vrf_finish_direct(skb);
+
+ return err;
+}
+
+static int vrf_ip_out_direct_finish(struct net *net, struct sock *sk,
+ struct sk_buff *skb)
+{
+ int err;
+
+ err = vrf_output_direct(net, sk, skb);
+ if (likely(err == 1))
+ err = vrf_ip_local_out(net, sk, skb);
+
+ return err;
+}
+
+static struct sk_buff *vrf_ip_out_direct(struct net_device *vrf_dev,
+ struct sock *sk,
+ struct sk_buff *skb)
+{
+ struct net *net = dev_net(vrf_dev);
+ int err;
+
+ skb->dev = vrf_dev;
+
+ err = nf_hook(NFPROTO_IPV4, NF_INET_LOCAL_OUT, net, sk,
+ skb, NULL, vrf_dev, vrf_ip_out_direct_finish);
+
+ if (likely(err == 1))
+ err = vrf_output_direct(net, sk, skb);
+
+ if (likely(err == 1))
+ return skb;
+
+ return NULL;
+}
+
+static struct sk_buff *vrf_ip_out(struct net_device *vrf_dev,
+ struct sock *sk,
+ struct sk_buff *skb)
+{
+ /* don't divert multicast or local broadcast */
+ if (ipv4_is_multicast(ip_hdr(skb)->daddr) ||
+ ipv4_is_lbcast(ip_hdr(skb)->daddr))
+ return skb;
+
+ vrf_nf_set_untracked(skb);
+
+ if (qdisc_tx_is_default(vrf_dev) ||
+ IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
+ return vrf_ip_out_direct(vrf_dev, sk, skb);
+
+ return vrf_ip_out_redirect(vrf_dev, skb);
+}
+
+/* called with rcu lock held */
+static struct sk_buff *vrf_l3_out(struct net_device *vrf_dev,
+ struct sock *sk,
+ struct sk_buff *skb,
+ u16 proto)
+{
+ switch (proto) {
+ case AF_INET:
+ return vrf_ip_out(vrf_dev, sk, skb);
+ case AF_INET6:
+ return vrf_ip6_out(vrf_dev, sk, skb);
+ }
+
+ return skb;
+}
+
+/* holding rtnl */
+static void vrf_rtable_release(struct net_device *dev, struct net_vrf *vrf)
+{
+ struct rtable *rth = rtnl_dereference(vrf->rth);
+ struct net *net = dev_net(dev);
+ struct dst_entry *dst;
+
+ RCU_INIT_POINTER(vrf->rth, NULL);
+ synchronize_rcu();
+
+ /* move dev in dst's to loopback so this VRF device can be deleted
+ * - based on dst_ifdown
+ */
+ if (rth) {
+ dst = &rth->dst;
+ netdev_ref_replace(dst->dev, net->loopback_dev,
+ &dst->dev_tracker, GFP_KERNEL);
+ dst->dev = net->loopback_dev;
+ dst_release(dst);
+ }
+}
+
+static int vrf_rtable_create(struct net_device *dev)
+{
+ struct net_vrf *vrf = netdev_priv(dev);
+ struct rtable *rth;
+
+ if (!fib_new_table(dev_net(dev), vrf->tb_id))
+ return -ENOMEM;
+
+ /* create a dst for routing packets out through a VRF device */
+ rth = rt_dst_alloc(dev, 0, RTN_UNICAST, 1);
+ if (!rth)
+ return -ENOMEM;
+
+ rth->dst.output = vrf_output;
+
+ rcu_assign_pointer(vrf->rth, rth);
+
+ return 0;
+}
+
+/**************************** device handling ********************/
+
+/* cycle interface to flush neighbor cache and move routes across tables */
+static void cycle_netdev(struct net_device *dev,
+ struct netlink_ext_ack *extack)
+{
+ unsigned int flags = dev->flags;
+ int ret;
+
+ if (!netif_running(dev))
+ return;
+
+ ret = dev_change_flags(dev, flags & ~IFF_UP, extack);
+ if (ret >= 0)
+ ret = dev_change_flags(dev, flags, extack);
+
+ if (ret < 0) {
+ netdev_err(dev,
+ "Failed to cycle device %s; route tables might be wrong!\n",
+ dev->name);
+ }
+}
+
+static int do_vrf_add_slave(struct net_device *dev, struct net_device *port_dev,
+ struct netlink_ext_ack *extack)
+{
+ int ret;
+
+ /* do not allow loopback device to be enslaved to a VRF.
+ * The vrf device acts as the loopback for the vrf.
+ */
+ if (port_dev == dev_net(dev)->loopback_dev) {
+ NL_SET_ERR_MSG(extack,
+ "Can not enslave loopback device to a VRF");
+ return -EOPNOTSUPP;
+ }
+
+ port_dev->priv_flags |= IFF_L3MDEV_SLAVE;
+ ret = netdev_master_upper_dev_link(port_dev, dev, NULL, NULL, extack);
+ if (ret < 0)
+ goto err;
+
+ cycle_netdev(port_dev, extack);
+
+ return 0;
+
+err:
+ port_dev->priv_flags &= ~IFF_L3MDEV_SLAVE;
+ return ret;
+}
+
+static int vrf_add_slave(struct net_device *dev, struct net_device *port_dev,
+ struct netlink_ext_ack *extack)
+{
+ if (netif_is_l3_master(port_dev)) {
+ NL_SET_ERR_MSG(extack,
+ "Can not enslave an L3 master device to a VRF");
+ return -EINVAL;
+ }
+
+ if (netif_is_l3_slave(port_dev))
+ return -EINVAL;
+
+ return do_vrf_add_slave(dev, port_dev, extack);
+}
+
+/* inverse of do_vrf_add_slave */
+static int do_vrf_del_slave(struct net_device *dev, struct net_device *port_dev)
+{
+ netdev_upper_dev_unlink(port_dev, dev);
+ port_dev->priv_flags &= ~IFF_L3MDEV_SLAVE;
+
+ cycle_netdev(port_dev, NULL);
+
+ return 0;
+}
+
+static int vrf_del_slave(struct net_device *dev, struct net_device *port_dev)
+{
+ return do_vrf_del_slave(dev, port_dev);
+}
+
+static void vrf_dev_uninit(struct net_device *dev)
+{
+ struct net_vrf *vrf = netdev_priv(dev);
+
+ vrf_rtable_release(dev, vrf);
+ vrf_rt6_release(dev, vrf);
+}
+
+static int vrf_dev_init(struct net_device *dev)
+{
+ struct net_vrf *vrf = netdev_priv(dev);
+
+ /* create the default dst which points back to us */
+ if (vrf_rtable_create(dev) != 0)
+ goto out_nomem;
+
+ if (vrf_rt6_create(dev) != 0)
+ goto out_rth;
+
+ dev->flags = IFF_MASTER | IFF_NOARP;
+
+ /* similarly, oper state is irrelevant; set to up to avoid confusion */
+ dev->operstate = IF_OPER_UP;
+ netdev_lockdep_set_classes(dev);
+ return 0;
+
+out_rth:
+ vrf_rtable_release(dev, vrf);
+out_nomem:
+ return -ENOMEM;
+}
+
+static const struct net_device_ops vrf_netdev_ops = {
+ .ndo_init = vrf_dev_init,
+ .ndo_uninit = vrf_dev_uninit,
+ .ndo_start_xmit = vrf_xmit,
+ .ndo_set_mac_address = eth_mac_addr,
+ .ndo_get_stats64 = vrf_get_stats64,
+ .ndo_add_slave = vrf_add_slave,
+ .ndo_del_slave = vrf_del_slave,
+};
+
+static u32 vrf_fib_table(const struct net_device *dev)
+{
+ struct net_vrf *vrf = netdev_priv(dev);
+
+ return vrf->tb_id;
+}
+
+static int vrf_rcv_finish(struct net *net, struct sock *sk, struct sk_buff *skb)
+{
+ kfree_skb(skb);
+ return 0;
+}
+
+static struct sk_buff *vrf_rcv_nfhook(u8 pf, unsigned int hook,
+ struct sk_buff *skb,
+ struct net_device *dev)
+{
+ struct net *net = dev_net(dev);
+
+ if (nf_hook(pf, hook, net, NULL, skb, dev, NULL, vrf_rcv_finish) != 1)
+ skb = NULL; /* kfree_skb(skb) handled by nf code */
+
+ return skb;
+}
+
+static int vrf_prepare_mac_header(struct sk_buff *skb,
+ struct net_device *vrf_dev, u16 proto)
+{
+ struct ethhdr *eth;
+ int err;
+
+ /* in general, we do not know if there is enough space in the head of
+ * the packet for hosting the mac header.
+ */
+ err = skb_cow_head(skb, LL_RESERVED_SPACE(vrf_dev));
+ if (unlikely(err))
+ /* no space in the skb head */
+ return -ENOBUFS;
+
+ __skb_push(skb, ETH_HLEN);
+ eth = (struct ethhdr *)skb->data;
+
+ skb_reset_mac_header(skb);
+ skb_reset_mac_len(skb);
+
+ /* we set the ethernet destination and the source addresses to the
+ * address of the VRF device.
+ */
+ ether_addr_copy(eth->h_dest, vrf_dev->dev_addr);
+ ether_addr_copy(eth->h_source, vrf_dev->dev_addr);
+ eth->h_proto = htons(proto);
+
+ /* the destination address of the Ethernet frame corresponds to the
+ * address set on the VRF interface; therefore, the packet is intended
+ * to be processed locally.
+ */
+ skb->protocol = eth->h_proto;
+ skb->pkt_type = PACKET_HOST;
+
+ skb_postpush_rcsum(skb, skb->data, ETH_HLEN);
+
+ skb_pull_inline(skb, ETH_HLEN);
+
+ return 0;
+}
+
+/* prepare and add the mac header to the packet if it was not set previously.
+ * In this way, packet sniffers such as tcpdump can parse the packet correctly.
+ * If the mac header was already set, the original mac header is left
+ * untouched and the function returns immediately.
+ */
+static int vrf_add_mac_header_if_unset(struct sk_buff *skb,
+ struct net_device *vrf_dev,
+ u16 proto, struct net_device *orig_dev)
+{
+ if (skb_mac_header_was_set(skb) && dev_has_header(orig_dev))
+ return 0;
+
+ return vrf_prepare_mac_header(skb, vrf_dev, proto);
+}
+
+#if IS_ENABLED(CONFIG_IPV6)
+/* neighbor handling is done with actual device; do not want
+ * to flip skb->dev for those ndisc packets. This really fails
+ * for multiple next protocols (e.g., NEXTHDR_HOP). But it is
+ * a start.
+ */
+static bool ipv6_ndisc_frame(const struct sk_buff *skb)
+{
+ const struct ipv6hdr *iph = ipv6_hdr(skb);
+ bool rc = false;
+
+ if (iph->nexthdr == NEXTHDR_ICMP) {
+ const struct icmp6hdr *icmph;
+ struct icmp6hdr _icmph;
+
+ icmph = skb_header_pointer(skb, sizeof(*iph),
+ sizeof(_icmph), &_icmph);
+ if (!icmph)
+ goto out;
+
+ switch (icmph->icmp6_type) {
+ case NDISC_ROUTER_SOLICITATION:
+ case NDISC_ROUTER_ADVERTISEMENT:
+ case NDISC_NEIGHBOUR_SOLICITATION:
+ case NDISC_NEIGHBOUR_ADVERTISEMENT:
+ case NDISC_REDIRECT:
+ rc = true;
+ break;
+ }
+ }
+
+out:
+ return rc;
+}
+
+static struct rt6_info *vrf_ip6_route_lookup(struct net *net,
+ const struct net_device *dev,
+ struct flowi6 *fl6,
+ int ifindex,
+ const struct sk_buff *skb,
+ int flags)
+{
+ struct net_vrf *vrf = netdev_priv(dev);
+
+ return ip6_pol_route(net, vrf->fib6_table, ifindex, fl6, skb, flags);
+}
+
+static void vrf_ip6_input_dst(struct sk_buff *skb, struct net_device *vrf_dev,
+ int ifindex)
+{
+ const struct ipv6hdr *iph = ipv6_hdr(skb);
+ struct flowi6 fl6 = {
+ .flowi6_iif = ifindex,
+ .flowi6_mark = skb->mark,
+ .flowi6_proto = iph->nexthdr,
+ .daddr = iph->daddr,
+ .saddr = iph->saddr,
+ .flowlabel = ip6_flowinfo(iph),
+ };
+ struct net *net = dev_net(vrf_dev);
+ struct rt6_info *rt6;
+
+ rt6 = vrf_ip6_route_lookup(net, vrf_dev, &fl6, ifindex, skb,
+ RT6_LOOKUP_F_HAS_SADDR | RT6_LOOKUP_F_IFACE);
+ if (unlikely(!rt6))
+ return;
+
+ if (unlikely(&rt6->dst == &net->ipv6.ip6_null_entry->dst))
+ return;
+
+ skb_dst_set(skb, &rt6->dst);
+}
+
+static struct sk_buff *vrf_ip6_rcv(struct net_device *vrf_dev,
+ struct sk_buff *skb)
+{
+ int orig_iif = skb->skb_iif;
+ bool need_strict = rt6_need_strict(&ipv6_hdr(skb)->daddr);
+ bool is_ndisc = ipv6_ndisc_frame(skb);
+
+ /* loopback, multicast & non-ND link-local traffic; do not push through
+ * packet taps again. Reset pkt_type for upper layers to process skb.
+ * For non-loopback strict packets, determine the dst using the original
+ * ifindex.
+ */
+ if (skb->pkt_type == PACKET_LOOPBACK || (need_strict && !is_ndisc)) {
+ skb->dev = vrf_dev;
+ skb->skb_iif = vrf_dev->ifindex;
+ IP6CB(skb)->flags |= IP6SKB_L3SLAVE;
+
+ if (skb->pkt_type == PACKET_LOOPBACK)
+ skb->pkt_type = PACKET_HOST;
+ else
+ vrf_ip6_input_dst(skb, vrf_dev, orig_iif);
+
+ goto out;
+ }
+
+ /* if packet is NDISC then keep the ingress interface */
+ if (!is_ndisc) {
+ struct net_device *orig_dev = skb->dev;
+
+ vrf_rx_stats(vrf_dev, skb->len);
+ skb->dev = vrf_dev;
+ skb->skb_iif = vrf_dev->ifindex;
+
+ if (!list_empty(&vrf_dev->ptype_all)) {
+ int err;
+
+ err = vrf_add_mac_header_if_unset(skb, vrf_dev,
+ ETH_P_IPV6,
+ orig_dev);
+ if (likely(!err)) {
+ skb_push(skb, skb->mac_len);
+ dev_queue_xmit_nit(skb, vrf_dev);
+ skb_pull(skb, skb->mac_len);
+ }
+ }
+
+ IP6CB(skb)->flags |= IP6SKB_L3SLAVE;
+ }
+
+ if (need_strict)
+ vrf_ip6_input_dst(skb, vrf_dev, orig_iif);
+
+ skb = vrf_rcv_nfhook(NFPROTO_IPV6, NF_INET_PRE_ROUTING, skb, vrf_dev);
+out:
+ return skb;
+}
+
+#else
+static struct sk_buff *vrf_ip6_rcv(struct net_device *vrf_dev,
+ struct sk_buff *skb)
+{
+ return skb;
+}
+#endif
+
+static struct sk_buff *vrf_ip_rcv(struct net_device *vrf_dev,
+ struct sk_buff *skb)
+{
+ struct net_device *orig_dev = skb->dev;
+
+ skb->dev = vrf_dev;
+ skb->skb_iif = vrf_dev->ifindex;
+ IPCB(skb)->flags |= IPSKB_L3SLAVE;
+
+ if (ipv4_is_multicast(ip_hdr(skb)->daddr))
+ goto out;
+
+ /* loopback traffic; do not push through packet taps again.
+ * Reset pkt_type for upper layers to process skb
+ */
+ if (skb->pkt_type == PACKET_LOOPBACK) {
+ skb->pkt_type = PACKET_HOST;
+ goto out;
+ }
+
+ vrf_rx_stats(vrf_dev, skb->len);
+
+ if (!list_empty(&vrf_dev->ptype_all)) {
+ int err;
+
+ err = vrf_add_mac_header_if_unset(skb, vrf_dev, ETH_P_IP,
+ orig_dev);
+ if (likely(!err)) {
+ skb_push(skb, skb->mac_len);
+ dev_queue_xmit_nit(skb, vrf_dev);
+ skb_pull(skb, skb->mac_len);
+ }
+ }
+
+ skb = vrf_rcv_nfhook(NFPROTO_IPV4, NF_INET_PRE_ROUTING, skb, vrf_dev);
+out:
+ return skb;
+}
+
+/* called with rcu lock held */
+static struct sk_buff *vrf_l3_rcv(struct net_device *vrf_dev,
+ struct sk_buff *skb,
+ u16 proto)
+{
+ switch (proto) {
+ case AF_INET:
+ return vrf_ip_rcv(vrf_dev, skb);
+ case AF_INET6:
+ return vrf_ip6_rcv(vrf_dev, skb);
+ }
+
+ return skb;
+}
+
+#if IS_ENABLED(CONFIG_IPV6)
+/* send to link-local or multicast address via interface enslaved to
+ * VRF device. Force lookup to VRF table without changing flow struct
+ * Note: Caller to this function must hold rcu_read_lock() and no refcnt
+ * is taken on the dst by this function.
+ */
+static struct dst_entry *vrf_link_scope_lookup(const struct net_device *dev,
+ struct flowi6 *fl6)
+{
+ struct net *net = dev_net(dev);
+ int flags = RT6_LOOKUP_F_IFACE | RT6_LOOKUP_F_DST_NOREF;
+ struct dst_entry *dst = NULL;
+ struct rt6_info *rt;
+
+ /* VRF device does not have a link-local address and
+ * sending packets to link-local or mcast addresses over
+ * a VRF device does not make sense
+ */
+ if (fl6->flowi6_oif == dev->ifindex) {
+ dst = &net->ipv6.ip6_null_entry->dst;
+ return dst;
+ }
+
+ if (!ipv6_addr_any(&fl6->saddr))
+ flags |= RT6_LOOKUP_F_HAS_SADDR;
+
+ rt = vrf_ip6_route_lookup(net, dev, fl6, fl6->flowi6_oif, NULL, flags);
+ if (rt)
+ dst = &rt->dst;
+
+ return dst;
+}
+#endif
+
+static const struct l3mdev_ops vrf_l3mdev_ops = {
+ .l3mdev_fib_table = vrf_fib_table,
+ .l3mdev_l3_rcv = vrf_l3_rcv,
+ .l3mdev_l3_out = vrf_l3_out,
+#if IS_ENABLED(CONFIG_IPV6)
+ .l3mdev_link_scope_lookup = vrf_link_scope_lookup,
+#endif
+};
+
+static void vrf_get_drvinfo(struct net_device *dev,
+ struct ethtool_drvinfo *info)
+{
+ strscpy(info->driver, DRV_NAME, sizeof(info->driver));
+ strscpy(info->version, DRV_VERSION, sizeof(info->version));
+}
+
+static const struct ethtool_ops vrf_ethtool_ops = {
+ .get_drvinfo = vrf_get_drvinfo,
+};
+
+static inline size_t vrf_fib_rule_nl_size(void)
+{
+ size_t sz;
+
+ sz = NLMSG_ALIGN(sizeof(struct fib_rule_hdr));
+ sz += nla_total_size(sizeof(u8)); /* FRA_L3MDEV */
+ sz += nla_total_size(sizeof(u32)); /* FRA_PRIORITY */
+ sz += nla_total_size(sizeof(u8)); /* FRA_PROTOCOL */
+
+ return sz;
+}
+
+static int vrf_fib_rule(const struct net_device *dev, __u8 family, bool add_it)
+{
+ struct fib_rule_hdr *frh;
+ struct nlmsghdr *nlh;
+ struct sk_buff *skb;
+ int err;
+
+ if ((family == AF_INET6 || family == RTNL_FAMILY_IP6MR) &&
+ !ipv6_mod_enabled())
+ return 0;
+
+ skb = nlmsg_new(vrf_fib_rule_nl_size(), GFP_KERNEL);
+ if (!skb)
+ return -ENOMEM;
+
+ nlh = nlmsg_put(skb, 0, 0, 0, sizeof(*frh), 0);
+ if (!nlh)
+ goto nla_put_failure;
+
+ /* rule only needs to appear once */
+ nlh->nlmsg_flags |= NLM_F_EXCL;
+
+ frh = nlmsg_data(nlh);
+ memset(frh, 0, sizeof(*frh));
+ frh->family = family;
+ frh->action = FR_ACT_TO_TBL;
+
+ if (nla_put_u8(skb, FRA_PROTOCOL, RTPROT_KERNEL))
+ goto nla_put_failure;
+
+ if (nla_put_u8(skb, FRA_L3MDEV, 1))
+ goto nla_put_failure;
+
+ if (nla_put_u32(skb, FRA_PRIORITY, FIB_RULE_PREF))
+ goto nla_put_failure;
+
+ nlmsg_end(skb, nlh);
+
+ /* fib_nl_{new,del}rule handling looks for net from skb->sk */
+ skb->sk = dev_net(dev)->rtnl;
+ if (add_it) {
+ err = fib_nl_newrule(skb, nlh, NULL);
+ if (err == -EEXIST)
+ err = 0;
+ } else {
+ err = fib_nl_delrule(skb, nlh, NULL);
+ if (err == -ENOENT)
+ err = 0;
+ }
+ nlmsg_free(skb);
+
+ return err;
+
+nla_put_failure:
+ nlmsg_free(skb);
+
+ return -EMSGSIZE;
+}
+
+static int vrf_add_fib_rules(const struct net_device *dev)
+{
+ int err;
+
+ err = vrf_fib_rule(dev, AF_INET, true);
+ if (err < 0)
+ goto out_err;
+
+ err = vrf_fib_rule(dev, AF_INET6, true);
+ if (err < 0)
+ goto ipv6_err;
+
+#if IS_ENABLED(CONFIG_IP_MROUTE_MULTIPLE_TABLES)
+ err = vrf_fib_rule(dev, RTNL_FAMILY_IPMR, true);
+ if (err < 0)
+ goto ipmr_err;
+#endif
+
+#if IS_ENABLED(CONFIG_IPV6_MROUTE_MULTIPLE_TABLES)
+ err = vrf_fib_rule(dev, RTNL_FAMILY_IP6MR, true);
+ if (err < 0)
+ goto ip6mr_err;
+#endif
+
+ return 0;
+
+#if IS_ENABLED(CONFIG_IPV6_MROUTE_MULTIPLE_TABLES)
+ip6mr_err:
+ vrf_fib_rule(dev, RTNL_FAMILY_IPMR, false);
+#endif
+
+#if IS_ENABLED(CONFIG_IP_MROUTE_MULTIPLE_TABLES)
+ipmr_err:
+ vrf_fib_rule(dev, AF_INET6, false);
+#endif
+
+ipv6_err:
+ vrf_fib_rule(dev, AF_INET, false);
+
+out_err:
+ netdev_err(dev, "Failed to add FIB rules.\n");
+ return err;
+}
+
+static void vrf_setup(struct net_device *dev)
+{
+ ether_setup(dev);
+
+ /* Initialize the device structure. */
+ dev->netdev_ops = &vrf_netdev_ops;
+ dev->l3mdev_ops = &vrf_l3mdev_ops;
+ dev->ethtool_ops = &vrf_ethtool_ops;
+ dev->needs_free_netdev = true;
+
+ /* Fill in device structure with ethernet-generic values. */
+ eth_hw_addr_random(dev);
+
+ /* don't acquire vrf device's netif_tx_lock when transmitting */
+ dev->features |= NETIF_F_LLTX;
+
+ /* don't allow vrf devices to change network namespaces. */
+ dev->features |= NETIF_F_NETNS_LOCAL;
+
+ /* does not make sense for a VLAN to be added to a vrf device */
+ dev->features |= NETIF_F_VLAN_CHALLENGED;
+
+ /* enable offload features */
+ dev->features |= NETIF_F_GSO_SOFTWARE;
+ dev->features |= NETIF_F_RXCSUM | NETIF_F_HW_CSUM | NETIF_F_SCTP_CRC;
+ dev->features |= NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HIGHDMA;
+
+ dev->hw_features = dev->features;
+ dev->hw_enc_features = dev->features;
+
+ /* default to no qdisc; user can add if desired */
+ dev->priv_flags |= IFF_NO_QUEUE;
+ dev->priv_flags |= IFF_NO_RX_HANDLER;
+ dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
+
+ /* VRF devices do not care about MTU, but if the MTU is set
+ * too low then the ipv4 and ipv6 protocols are disabled
+ * which breaks networking.
+ */
+ dev->min_mtu = IPV6_MIN_MTU;
+ dev->max_mtu = IP6_MAX_MTU;
+ dev->mtu = dev->max_mtu;
+
+ dev->pcpu_stat_type = NETDEV_PCPU_STAT_DSTATS;
+}
+
+static int vrf_validate(struct nlattr *tb[], struct nlattr *data[],
+ struct netlink_ext_ack *extack)
+{
+ if (tb[IFLA_ADDRESS]) {
+ if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) {
+ NL_SET_ERR_MSG(extack, "Invalid hardware address");
+ return -EINVAL;
+ }
+ if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) {
+ NL_SET_ERR_MSG(extack, "Invalid hardware address");
+ return -EADDRNOTAVAIL;
+ }
+ }
+ return 0;
+}
+
+static void vrf_dellink(struct net_device *dev, struct list_head *head)
+{
+ struct net_device *port_dev;
+ struct list_head *iter;
+
+ netdev_for_each_lower_dev(dev, port_dev, iter)
+ vrf_del_slave(dev, port_dev);
+
+ vrf_map_unregister_dev(dev);
+
+ unregister_netdevice_queue(dev, head);
+}
+
+static int vrf_newlink(struct net *src_net, struct net_device *dev,
+ struct nlattr *tb[], struct nlattr *data[],
+ struct netlink_ext_ack *extack)
+{
+ struct net_vrf *vrf = netdev_priv(dev);
+ struct netns_vrf *nn_vrf;
+ bool *add_fib_rules;
+ struct net *net;
+ int err;
+
+ if (!data || !data[IFLA_VRF_TABLE]) {
+ NL_SET_ERR_MSG(extack, "VRF table id is missing");
+ return -EINVAL;
+ }
+
+ vrf->tb_id = nla_get_u32(data[IFLA_VRF_TABLE]);
+ if (vrf->tb_id == RT_TABLE_UNSPEC) {
+ NL_SET_ERR_MSG_ATTR(extack, data[IFLA_VRF_TABLE],
+ "Invalid VRF table id");
+ return -EINVAL;
+ }
+
+ dev->priv_flags |= IFF_L3MDEV_MASTER;
+
+ err = register_netdevice(dev);
+ if (err)
+ goto out;
+
+ /* mapping between table_id and vrf;
+ * note: such binding could not be done in the dev init function
+ * because dev->ifindex id is not available yet.
+ */
+ vrf->ifindex = dev->ifindex;
+
+ err = vrf_map_register_dev(dev, extack);
+ if (err) {
+ unregister_netdevice(dev);
+ goto out;
+ }
+
+ net = dev_net(dev);
+ nn_vrf = net_generic(net, vrf_net_id);
+
+ add_fib_rules = &nn_vrf->add_fib_rules;
+ if (*add_fib_rules) {
+ err = vrf_add_fib_rules(dev);
+ if (err) {
+ vrf_map_unregister_dev(dev);
+ unregister_netdevice(dev);
+ goto out;
+ }
+ *add_fib_rules = false;
+ }
+
+out:
+ return err;
+}
+
+static size_t vrf_nl_getsize(const struct net_device *dev)
+{
+ return nla_total_size(sizeof(u32)); /* IFLA_VRF_TABLE */
+}
+
+static int vrf_fillinfo(struct sk_buff *skb,
+ const struct net_device *dev)
+{
+ struct net_vrf *vrf = netdev_priv(dev);
+
+ return nla_put_u32(skb, IFLA_VRF_TABLE, vrf->tb_id);
+}
+
+static size_t vrf_get_slave_size(const struct net_device *bond_dev,
+ const struct net_device *slave_dev)
+{
+ return nla_total_size(sizeof(u32)); /* IFLA_VRF_PORT_TABLE */
+}
+
+static int vrf_fill_slave_info(struct sk_buff *skb,
+ const struct net_device *vrf_dev,
+ const struct net_device *slave_dev)
+{
+ struct net_vrf *vrf = netdev_priv(vrf_dev);
+
+ if (nla_put_u32(skb, IFLA_VRF_PORT_TABLE, vrf->tb_id))
+ return -EMSGSIZE;
+
+ return 0;
+}
+
+static const struct nla_policy vrf_nl_policy[IFLA_VRF_MAX + 1] = {
+ [IFLA_VRF_TABLE] = { .type = NLA_U32 },
+};
+
+static struct rtnl_link_ops vrf_link_ops __read_mostly = {
+ .kind = DRV_NAME,
+ .priv_size = sizeof(struct net_vrf),
+
+ .get_size = vrf_nl_getsize,
+ .policy = vrf_nl_policy,
+ .validate = vrf_validate,
+ .fill_info = vrf_fillinfo,
+
+ .get_slave_size = vrf_get_slave_size,
+ .fill_slave_info = vrf_fill_slave_info,
+
+ .newlink = vrf_newlink,
+ .dellink = vrf_dellink,
+ .setup = vrf_setup,
+ .maxtype = IFLA_VRF_MAX,
+};
+
+static int vrf_device_event(struct notifier_block *unused,
+ unsigned long event, void *ptr)
+{
+ struct net_device *dev = netdev_notifier_info_to_dev(ptr);
+
+ /* only care about unregister events to drop slave references */
+ if (event == NETDEV_UNREGISTER) {
+ struct net_device *vrf_dev;
+
+ if (!netif_is_l3_slave(dev))
+ goto out;
+
+ vrf_dev = netdev_master_upper_dev_get(dev);
+ vrf_del_slave(vrf_dev, dev);
+ }
+out:
+ return NOTIFY_DONE;
+}
+
+static struct notifier_block vrf_notifier_block __read_mostly = {
+ .notifier_call = vrf_device_event,
+};
+
+static int vrf_map_init(struct vrf_map *vmap)
+{
+ spin_lock_init(&vmap->vmap_lock);
+ hash_init(vmap->ht);
+
+ vmap->strict_mode = false;
+
+ return 0;
+}
+
+#ifdef CONFIG_SYSCTL
+static bool vrf_strict_mode(struct vrf_map *vmap)
+{
+ bool strict_mode;
+
+ vrf_map_lock(vmap);
+ strict_mode = vmap->strict_mode;
+ vrf_map_unlock(vmap);
+
+ return strict_mode;
+}
+
+static int vrf_strict_mode_change(struct vrf_map *vmap, bool new_mode)
+{
+ bool *cur_mode;
+ int res = 0;
+
+ vrf_map_lock(vmap);
+
+ cur_mode = &vmap->strict_mode;
+ if (*cur_mode == new_mode)
+ goto unlock;
+
+ if (*cur_mode) {
+ /* disable strict mode */
+ *cur_mode = false;
+ } else {
+ if (vmap->shared_tables) {
+ /* we cannot allow strict_mode because there are some
+ * vrfs that share one or more tables.
+ */
+ res = -EBUSY;
+ goto unlock;
+ }
+
+ /* no tables are shared among vrfs, so we can go back
+ * to 1:1 association between a vrf with its table.
+ */
+ *cur_mode = true;
+ }
+
+unlock:
+ vrf_map_unlock(vmap);
+
+ return res;
+}
+
+static int vrf_shared_table_handler(struct ctl_table *table, int write,
+ void *buffer, size_t *lenp, loff_t *ppos)
+{
+ struct net *net = (struct net *)table->extra1;
+ struct vrf_map *vmap = netns_vrf_map(net);
+ int proc_strict_mode = 0;
+ struct ctl_table tmp = {
+ .procname = table->procname,
+ .data = &proc_strict_mode,
+ .maxlen = sizeof(int),
+ .mode = table->mode,
+ .extra1 = SYSCTL_ZERO,
+ .extra2 = SYSCTL_ONE,
+ };
+ int ret;
+
+ if (!write)
+ proc_strict_mode = vrf_strict_mode(vmap);
+
+ ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
+
+ if (write && ret == 0)
+ ret = vrf_strict_mode_change(vmap, (bool)proc_strict_mode);
+
+ return ret;
+}
+
+static const struct ctl_table vrf_table[] = {
+ {
+ .procname = "strict_mode",
+ .data = NULL,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = vrf_shared_table_handler,
+ /* set by the vrf_netns_init */
+ .extra1 = NULL,
+ },
+ { },
+};
+
+static int vrf_netns_init_sysctl(struct net *net, struct netns_vrf *nn_vrf)
+{
+ struct ctl_table *table;
+
+ table = kmemdup(vrf_table, sizeof(vrf_table), GFP_KERNEL);
+ if (!table)
+ return -ENOMEM;
+
+ /* init the extra1 parameter with the reference to current netns */
+ table[0].extra1 = net;
+
+ nn_vrf->ctl_hdr = register_net_sysctl_sz(net, "net/vrf", table,
+ ARRAY_SIZE(vrf_table));
+ if (!nn_vrf->ctl_hdr) {
+ kfree(table);
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+static void vrf_netns_exit_sysctl(struct net *net)
+{
+ struct netns_vrf *nn_vrf = net_generic(net, vrf_net_id);
+ struct ctl_table *table;
+
+ table = nn_vrf->ctl_hdr->ctl_table_arg;
+ unregister_net_sysctl_table(nn_vrf->ctl_hdr);
+ kfree(table);
+}
+#else
+static int vrf_netns_init_sysctl(struct net *net, struct netns_vrf *nn_vrf)
+{
+ return 0;
+}
+
+static void vrf_netns_exit_sysctl(struct net *net)
+{
+}
+#endif
+
+/* Initialize per network namespace state */
+static int __net_init vrf_netns_init(struct net *net)
+{
+ struct netns_vrf *nn_vrf = net_generic(net, vrf_net_id);
+
+ nn_vrf->add_fib_rules = true;
+ vrf_map_init(&nn_vrf->vmap);
+
+ return vrf_netns_init_sysctl(net, nn_vrf);
+}
+
+static void __net_exit vrf_netns_exit(struct net *net)
+{
+ vrf_netns_exit_sysctl(net);
+}
+
+static struct pernet_operations vrf_net_ops __net_initdata = {
+ .init = vrf_netns_init,
+ .exit = vrf_netns_exit,
+ .id = &vrf_net_id,
+ .size = sizeof(struct netns_vrf),
+};
+
+static int __init vrf_init_module(void)
+{
+ int rc;
+
+ register_netdevice_notifier(&vrf_notifier_block);
+
+ rc = register_pernet_subsys(&vrf_net_ops);
+ if (rc < 0)
+ goto error;
+
+ rc = l3mdev_table_lookup_register(L3MDEV_TYPE_VRF,
+ vrf_ifindex_lookup_by_table_id);
+ if (rc < 0)
+ goto unreg_pernet;
+
+ rc = rtnl_link_register(&vrf_link_ops);
+ if (rc < 0)
+ goto table_lookup_unreg;
+
+ return 0;
+
+table_lookup_unreg:
+ l3mdev_table_lookup_unregister(L3MDEV_TYPE_VRF,
+ vrf_ifindex_lookup_by_table_id);
+
+unreg_pernet:
+ unregister_pernet_subsys(&vrf_net_ops);
+
+error:
+ unregister_netdevice_notifier(&vrf_notifier_block);
+ return rc;
+}
+
+module_init(vrf_init_module);
+MODULE_AUTHOR("Shrijeet Mukherjee, David Ahern");
+MODULE_DESCRIPTION("Device driver to instantiate VRF domains");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_RTNL_LINK(DRV_NAME);
+MODULE_VERSION(DRV_VERSION);