diff options
| -rw-r--r-- | drivers/net/veth.c | 9 | ||||
| -rw-r--r-- | include/linux/netdevice.h | 4 | ||||
| -rw-r--r-- | include/uapi/linux/bpf.h | 17 | ||||
| -rw-r--r-- | net/core/dev.c | 15 | ||||
| -rw-r--r-- | net/core/filter.c | 54 | ||||
| -rw-r--r-- | tools/include/uapi/linux/bpf.h | 17 |
6 files changed, 106 insertions, 10 deletions
diff --git a/drivers/net/veth.c b/drivers/net/veth.c index 091e5b4ba042..8c737668008a 100644 --- a/drivers/net/veth.c +++ b/drivers/net/veth.c @@ -420,6 +420,14 @@ static int veth_select_rxq(struct net_device *dev) return smp_processor_id() % dev->real_num_rx_queues; } +static struct net_device *veth_peer_dev(struct net_device *dev) +{ + struct veth_priv *priv = netdev_priv(dev); + + /* Callers must be under RCU read side. */ + return rcu_dereference(priv->peer); +} + static int veth_xdp_xmit(struct net_device *dev, int n, struct xdp_frame **frames, u32 flags, bool ndo_xmit) @@ -1224,6 +1232,7 @@ static const struct net_device_ops veth_netdev_ops = { .ndo_set_rx_headroom = veth_set_rx_headroom, .ndo_bpf = veth_xdp, .ndo_xdp_xmit = veth_ndo_xdp_xmit, + .ndo_get_peer_dev = veth_peer_dev, }; #define VETH_FEATURES (NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HW_CSUM | \ diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 28cfa53daf72..0533f86018dd 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -1277,6 +1277,9 @@ struct netdev_net_notifier { * int (*ndo_tunnel_ctl)(struct net_device *dev, struct ip_tunnel_parm *p, * int cmd); * Add, change, delete or get information on an IPv4 tunnel. + * struct net_device *(*ndo_get_peer_dev)(struct net_device *dev); + * If a device is paired with a peer device, return the peer instance. + * The caller must be under RCU read context. */ struct net_device_ops { int (*ndo_init)(struct net_device *dev); @@ -1484,6 +1487,7 @@ struct net_device_ops { struct devlink_port * (*ndo_get_devlink_port)(struct net_device *dev); int (*ndo_tunnel_ctl)(struct net_device *dev, struct ip_tunnel_parm *p, int cmd); + struct net_device * (*ndo_get_peer_dev)(struct net_device *dev); }; /** diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 4272cc53d478..b97bc5abb3b8 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -3719,6 +3719,22 @@ union bpf_attr { * never return NULL. * Return * A pointer pointing to the kernel percpu variable on this cpu. + * + * long bpf_redirect_peer(u32 ifindex, u64 flags) + * Description + * Redirect the packet to another net device of index *ifindex*. + * This helper is somewhat similar to **bpf_redirect**\ (), except + * that the redirection happens to the *ifindex*' peer device and + * the netns switch takes place from ingress to ingress without + * going through the CPU's backlog queue. + * + * The *flags* argument is reserved and must be 0. The helper is + * currently only supported for tc BPF program types at the ingress + * hook and for veth device types. The peer device must reside in a + * different network namespace. + * Return + * The helper returns **TC_ACT_REDIRECT** on success or + * **TC_ACT_SHOT** on error. */ #define __BPF_FUNC_MAPPER(FN) \ FN(unspec), \ @@ -3876,6 +3892,7 @@ union bpf_attr { FN(redirect_neigh), \ FN(bpf_per_cpu_ptr), \ FN(bpf_this_cpu_ptr), \ + FN(redirect_peer), \ /* */ /* integer value in 'imm' field of BPF_CALL instruction selects which helper diff --git a/net/core/dev.c b/net/core/dev.c index 9d55bf5d1a65..7dd015823593 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -4930,7 +4930,7 @@ EXPORT_SYMBOL_GPL(br_fdb_test_addr_hook); static inline struct sk_buff * sch_handle_ingress(struct sk_buff *skb, struct packet_type **pt_prev, int *ret, - struct net_device *orig_dev) + struct net_device *orig_dev, bool *another) { #ifdef CONFIG_NET_CLS_ACT struct mini_Qdisc *miniq = rcu_dereference_bh(skb->dev->miniq_ingress); @@ -4974,7 +4974,11 @@ sch_handle_ingress(struct sk_buff *skb, struct packet_type **pt_prev, int *ret, * redirecting to another netdev */ __skb_push(skb, skb->mac_len); - skb_do_redirect(skb); + if (skb_do_redirect(skb) == -EAGAIN) { + __skb_pull(skb, skb->mac_len); + *another = true; + break; + } return NULL; case TC_ACT_CONSUMED: return NULL; @@ -5163,7 +5167,12 @@ another_round: skip_taps: #ifdef CONFIG_NET_INGRESS if (static_branch_unlikely(&ingress_needed_key)) { - skb = sch_handle_ingress(skb, &pt_prev, &ret, orig_dev); + bool another = false; + + skb = sch_handle_ingress(skb, &pt_prev, &ret, orig_dev, + &another); + if (another) + goto another_round; if (!skb) goto out; diff --git a/net/core/filter.c b/net/core/filter.c index 5da44b11e1ec..fab951c6be57 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -2380,8 +2380,9 @@ out: /* Internal, non-exposed redirect flags. */ enum { - BPF_F_NEIGH = (1ULL << 1), -#define BPF_F_REDIRECT_INTERNAL (BPF_F_NEIGH) + BPF_F_NEIGH = (1ULL << 1), + BPF_F_PEER = (1ULL << 2), +#define BPF_F_REDIRECT_INTERNAL (BPF_F_NEIGH | BPF_F_PEER) }; BPF_CALL_3(bpf_clone_redirect, struct sk_buff *, skb, u32, ifindex, u64, flags) @@ -2430,19 +2431,35 @@ EXPORT_PER_CPU_SYMBOL_GPL(bpf_redirect_info); int skb_do_redirect(struct sk_buff *skb) { struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info); + struct net *net = dev_net(skb->dev); struct net_device *dev; u32 flags = ri->flags; - dev = dev_get_by_index_rcu(dev_net(skb->dev), ri->tgt_index); + dev = dev_get_by_index_rcu(net, ri->tgt_index); ri->tgt_index = 0; - if (unlikely(!dev)) { - kfree_skb(skb); - return -EINVAL; + ri->flags = 0; + if (unlikely(!dev)) + goto out_drop; + if (flags & BPF_F_PEER) { + const struct net_device_ops *ops = dev->netdev_ops; + + if (unlikely(!ops->ndo_get_peer_dev || + !skb_at_tc_ingress(skb))) + goto out_drop; + dev = ops->ndo_get_peer_dev(dev); + if (unlikely(!dev || + !is_skb_forwardable(dev, skb) || + net_eq(net, dev_net(dev)))) + goto out_drop; + skb->dev = dev; + return -EAGAIN; } - return flags & BPF_F_NEIGH ? __bpf_redirect_neigh(skb, dev) : __bpf_redirect(skb, dev, flags); +out_drop: + kfree_skb(skb); + return -EINVAL; } BPF_CALL_2(bpf_redirect, u32, ifindex, u64, flags) @@ -2466,6 +2483,27 @@ static const struct bpf_func_proto bpf_redirect_proto = { .arg2_type = ARG_ANYTHING, }; +BPF_CALL_2(bpf_redirect_peer, u32, ifindex, u64, flags) +{ + struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info); + + if (unlikely(flags)) + return TC_ACT_SHOT; + + ri->flags = BPF_F_PEER; + ri->tgt_index = ifindex; + + return TC_ACT_REDIRECT; +} + +static const struct bpf_func_proto bpf_redirect_peer_proto = { + .func = bpf_redirect_peer, + .gpl_only = false, + .ret_type = RET_INTEGER, + .arg1_type = ARG_ANYTHING, + .arg2_type = ARG_ANYTHING, +}; + BPF_CALL_2(bpf_redirect_neigh, u32, ifindex, u64, flags) { struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info); @@ -7053,6 +7091,8 @@ tc_cls_act_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return &bpf_redirect_proto; case BPF_FUNC_redirect_neigh: return &bpf_redirect_neigh_proto; + case BPF_FUNC_redirect_peer: + return &bpf_redirect_peer_proto; case BPF_FUNC_get_route_realm: return &bpf_get_route_realm_proto; case BPF_FUNC_get_hash_recalc: diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index 4272cc53d478..b97bc5abb3b8 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -3719,6 +3719,22 @@ union bpf_attr { * never return NULL. * Return * A pointer pointing to the kernel percpu variable on this cpu. + * + * long bpf_redirect_peer(u32 ifindex, u64 flags) + * Description + * Redirect the packet to another net device of index *ifindex*. + * This helper is somewhat similar to **bpf_redirect**\ (), except + * that the redirection happens to the *ifindex*' peer device and + * the netns switch takes place from ingress to ingress without + * going through the CPU's backlog queue. + * + * The *flags* argument is reserved and must be 0. The helper is + * currently only supported for tc BPF program types at the ingress + * hook and for veth device types. The peer device must reside in a + * different network namespace. + * Return + * The helper returns **TC_ACT_REDIRECT** on success or + * **TC_ACT_SHOT** on error. */ #define __BPF_FUNC_MAPPER(FN) \ FN(unspec), \ @@ -3876,6 +3892,7 @@ union bpf_attr { FN(redirect_neigh), \ FN(bpf_per_cpu_ptr), \ FN(bpf_this_cpu_ptr), \ + FN(redirect_peer), \ /* */ /* integer value in 'imm' field of BPF_CALL instruction selects which helper |