diff --git a/drivers/net/vrf.c b/drivers/net/vrf.c index d356f5d0f7b0..1b214ea4619a 100644 --- a/drivers/net/vrf.c +++ b/drivers/net/vrf.c @@ -44,7 +44,9 @@ struct net_vrf { struct rtable __rcu *rth; + struct rtable __rcu *rth_local; struct rt6_info __rcu *rt6; + struct rt6_info __rcu *rt6_local; u32 tb_id; }; @@ -54,9 +56,20 @@ struct pcpu_dstats { 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++; @@ -91,6 +104,34 @@ static struct rtnl_link_stats64 *vrf_get_stats64(struct net_device *dev, return stats; } +/* 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); + skb_dst_force(skb); + + /* 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; +} + #if IS_ENABLED(CONFIG_IPV6) static netdev_tx_t vrf_process_v6_outbound(struct sk_buff *skb, struct net_device *dev) @@ -117,8 +158,51 @@ static netdev_tx_t vrf_process_v6_outbound(struct sk_buff *skb, goto err; skb_dst_drop(skb); + + /* if dst.dev is loopback or the VRF device again this is locally + * originated traffic destined to a local address. Short circuit + * to Rx path using our local dst + */ + if (dst->dev == net->loopback_dev || dst->dev == dev) { + struct net_vrf *vrf = netdev_priv(dev); + struct rt6_info *rt6_local; + + /* release looked up dst and use cached local dst */ + dst_release(dst); + + rcu_read_lock(); + + rt6_local = rcu_dereference(vrf->rt6_local); + if (unlikely(!rt6_local)) { + rcu_read_unlock(); + goto err; + } + + /* Ordering issue: cached local dst is created on newlink + * before the IPv6 initialization. Using the local dst + * requires rt6i_idev to be set so make sure it is. + */ + if (unlikely(!rt6_local->rt6i_idev)) { + rt6_local->rt6i_idev = in6_dev_get(dev); + if (!rt6_local->rt6i_idev) { + rcu_read_unlock(); + goto err; + } + } + + dst = &rt6_local->dst; + dst_hold(dst); + + rcu_read_unlock(); + + return vrf_local_xmit(skb, dev, &rt6_local->dst); + } + skb_dst_set(skb, dst); + /* strip the ethernet header added for pass through VRF device */ + __skb_pull(skb, skb_network_offset(skb)); + ret = ip6_local_out(net, skb->sk, skb); if (unlikely(net_xmit_eval(ret))) dev->stats.tx_errors++; @@ -139,29 +223,6 @@ static netdev_tx_t vrf_process_v6_outbound(struct sk_buff *skb, } #endif -static int vrf_send_v4_prep(struct sk_buff *skb, struct flowi4 *fl4, - struct net_device *vrf_dev) -{ - struct rtable *rt; - int err = 1; - - rt = ip_route_output_flow(dev_net(vrf_dev), fl4, NULL); - if (IS_ERR(rt)) - goto out; - - /* TO-DO: what about broadcast ? */ - if (rt->rt_type != RTN_UNICAST && rt->rt_type != RTN_LOCAL) { - ip_rt_put(rt); - goto out; - } - - skb_dst_drop(skb); - skb_dst_set(skb, &rt->dst); - err = 0; -out: - return err; -} - static netdev_tx_t vrf_process_v4_outbound(struct sk_buff *skb, struct net_device *vrf_dev) { @@ -176,10 +237,52 @@ static netdev_tx_t vrf_process_v4_outbound(struct sk_buff *skb, FLOWI_FLAG_SKIP_NH_OIF, .daddr = ip4h->daddr, }; + struct net *net = dev_net(vrf_dev); + struct rtable *rt; - if (vrf_send_v4_prep(skb, &fl4, vrf_dev)) + rt = ip_route_output_flow(net, &fl4, NULL); + if (IS_ERR(rt)) goto err; + if (rt->rt_type != RTN_UNICAST && rt->rt_type != RTN_LOCAL) { + ip_rt_put(rt); + goto err; + } + + skb_dst_drop(skb); + + /* if dst.dev is loopback or the VRF device again this is locally + * originated traffic destined to a local address. Short circuit + * to Rx path using our local dst + */ + if (rt->dst.dev == net->loopback_dev || rt->dst.dev == vrf_dev) { + struct net_vrf *vrf = netdev_priv(vrf_dev); + struct rtable *rth_local; + struct dst_entry *dst = NULL; + + ip_rt_put(rt); + + rcu_read_lock(); + + rth_local = rcu_dereference(vrf->rth_local); + if (likely(rth_local)) { + dst = &rth_local->dst; + dst_hold(dst); + } + + rcu_read_unlock(); + + if (unlikely(!dst)) + goto err; + + return vrf_local_xmit(skb, vrf_dev, 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); @@ -200,9 +303,6 @@ err: static netdev_tx_t is_ip_tx_frame(struct sk_buff *skb, struct net_device *dev) { - /* strip the ethernet header added for pass through VRF device */ - __skb_pull(skb, skb_network_offset(skb)); - switch (skb->protocol) { case htons(ETH_P_IP): return vrf_process_v4_outbound(skb, dev); @@ -277,27 +377,38 @@ static int vrf_output6(struct net *net, struct sock *sk, struct sk_buff *skb) static void vrf_rt6_release(struct net_vrf *vrf) { struct rt6_info *rt6 = rtnl_dereference(vrf->rt6); + struct rt6_info *rt6_local = rtnl_dereference(vrf->rt6_local); - rcu_assign_pointer(vrf->rt6, NULL); + RCU_INIT_POINTER(vrf->rt6, NULL); + RCU_INIT_POINTER(vrf->rt6_local, NULL); + synchronize_rcu(); if (rt6) dst_release(&rt6->dst); + + if (rt6_local) { + if (rt6_local->rt6i_idev) + in6_dev_put(rt6_local->rt6i_idev); + + dst_release(&rt6_local->dst); + } } static int vrf_rt6_create(struct net_device *dev) { + int flags = DST_HOST | DST_NOPOLICY | DST_NOXFRM | DST_NOCACHE; struct net_vrf *vrf = netdev_priv(dev); struct net *net = dev_net(dev); struct fib6_table *rt6i_table; - struct rt6_info *rt6; + struct rt6_info *rt6, *rt6_local; int rc = -ENOMEM; rt6i_table = fib6_new_table(net, vrf->tb_id); if (!rt6i_table) goto out; - rt6 = ip6_dst_alloc(net, dev, - DST_HOST | DST_NOPOLICY | DST_NOXFRM | DST_NOCACHE); + /* create a dst for routing packets out a VRF device */ + rt6 = ip6_dst_alloc(net, dev, flags); if (!rt6) goto out; @@ -305,7 +416,25 @@ static int vrf_rt6_create(struct net_device *dev) rt6->rt6i_table = rt6i_table; rt6->dst.output = vrf_output6; + + /* create a dst for local routing - packets sent locally + * to local address via the VRF device as a loopback + */ + rt6_local = ip6_dst_alloc(net, dev, flags); + if (!rt6_local) { + dst_release(&rt6->dst); + goto out; + } + + dst_hold(&rt6_local->dst); + + rt6_local->rt6i_idev = in6_dev_get(dev); + rt6_local->rt6i_flags = RTF_UP | RTF_NONEXTHOP | RTF_LOCAL; + rt6_local->rt6i_table = rt6i_table; + rt6_local->dst.input = ip6_input; + rcu_assign_pointer(vrf->rt6, rt6); + rcu_assign_pointer(vrf->rt6_local, rt6_local); rc = 0; out: @@ -384,29 +513,48 @@ static int vrf_output(struct net *net, struct sock *sk, struct sk_buff *skb) static void vrf_rtable_release(struct net_vrf *vrf) { struct rtable *rth = rtnl_dereference(vrf->rth); + struct rtable *rth_local = rtnl_dereference(vrf->rth_local); - rcu_assign_pointer(vrf->rth, NULL); + RCU_INIT_POINTER(vrf->rth, NULL); + RCU_INIT_POINTER(vrf->rth_local, NULL); + synchronize_rcu(); if (rth) dst_release(&rth->dst); + + if (rth_local) + dst_release(&rth_local->dst); } static int vrf_rtable_create(struct net_device *dev) { struct net_vrf *vrf = netdev_priv(dev); - struct rtable *rth; + struct rtable *rth, *rth_local; 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, 0); if (!rth) return -ENOMEM; + /* create a dst for local ingress routing - packets sent locally + * to local address via the VRF device as a loopback + */ + rth_local = rt_dst_alloc(dev, RTCF_LOCAL, RTN_LOCAL, 1, 1, 0); + if (!rth_local) { + dst_release(&rth->dst); + return -ENOMEM; + } + rth->dst.output = vrf_output; rth->rt_table_id = vrf->tb_id; + rth_local->rt_table_id = vrf->tb_id; + rcu_assign_pointer(vrf->rth, rth); + rcu_assign_pointer(vrf->rth_local, rth_local); return 0; } @@ -632,6 +780,16 @@ out: static struct sk_buff *vrf_ip6_rcv(struct net_device *vrf_dev, struct sk_buff *skb) { + /* 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->dev = vrf_dev; + skb->skb_iif = vrf_dev->ifindex; + skb->pkt_type = PACKET_HOST; + goto out; + } + /* if packet is NDISC keep the ingress interface */ if (!ipv6_ndisc_frame(skb)) { skb->dev = vrf_dev; @@ -644,6 +802,7 @@ static struct sk_buff *vrf_ip6_rcv(struct net_device *vrf_dev, IP6CB(skb)->flags |= IP6SKB_L3SLAVE; } +out: return skb; } @@ -661,10 +820,19 @@ static struct sk_buff *vrf_ip_rcv(struct net_device *vrf_dev, skb->dev = vrf_dev; skb->skb_iif = vrf_dev->ifindex; + /* 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; + } + skb_push(skb, skb->mac_len); dev_queue_xmit_nit(skb, vrf_dev); skb_pull(skb, skb->mac_len); +out: return skb; }