| // 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/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; |
| }; |
| |
| struct pcpu_dstats { |
| u64 tx_pkts; |
| u64 tx_bytes; |
| u64 tx_drps; |
| u64 rx_pkts; |
| u64 rx_bytes; |
| u64 rx_drps; |
| struct u64_stats_sync syncp; |
| }; |
| |
| 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_pkts++; |
| 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_irq(&dstats->syncp); |
| tbytes = dstats->tx_bytes; |
| tpkts = dstats->tx_pkts; |
| tdrops = dstats->tx_drps; |
| rbytes = dstats->rx_bytes; |
| rpkts = dstats->rx_pkts; |
| } while (u64_stats_fetch_retry_irq(&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_drps); |
| |
| 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_oif = 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; |
| fl6.flowi6_flags = FLOWI_FLAG_SKIP_NH_OIF; |
| |
| 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_oif = vrf_dev->ifindex; |
| fl4.flowi4_iif = LOOPBACK_IFINDEX; |
| fl4.flowi4_tos = RT_TOS(ip4h->tos); |
| fl4.flowi4_flags = FLOWI_FLAG_ANYSRC | FLOWI_FLAG_SKIP_NH_OIF; |
| 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_pkts++; |
| dstats->tx_bytes += len; |
| u64_stats_update_end(&dstats->syncp); |
| } else { |
| this_cpu_inc(dev->dstats->tx_drps); |
| } |
| |
| 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; |
| |
| rcu_read_lock_bh(); |
| dev_queue_xmit_nit(skb, vrf_dev); |
| rcu_read_unlock_bh(); |
| |
| 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_bh(); |
| 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_bh(); |
| return ret; |
| } |
| rcu_read_unlock_bh(); |
| |
| 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; |
| dev_put(dst->dev); |
| dst->dev = net->loopback_dev; |
| dev_hold(dst->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_bh(); |
| |
| 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_bh(); |
| return ret; |
| } |
| |
| rcu_read_unlock_bh(); |
| 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; |
| dev_put(dst->dev); |
| dst->dev = net->loopback_dev; |
| dev_hold(dst->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, 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); |
| |
| free_percpu(dev->dstats); |
| dev->dstats = NULL; |
| } |
| |
| static int vrf_dev_init(struct net_device *dev) |
| { |
| struct net_vrf *vrf = netdev_priv(dev); |
| |
| dev->dstats = netdev_alloc_pcpu_stats(struct pcpu_dstats); |
| if (!dev->dstats) |
| goto out_nomem; |
| |
| /* create the default dst which points back to us */ |
| if (vrf_rtable_create(dev) != 0) |
| goto out_stats; |
| |
| 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_stats: |
| free_percpu(dev->dstats); |
| dev->dstats = NULL; |
| 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 strict packets with a source LLA, 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 if (ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL) |
| 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) |
| { |
| strlcpy(info->driver, DRV_NAME, sizeof(info->driver)); |
| strlcpy(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; |
| } |
| |
| 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(net, "net/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); |