diff options
Diffstat (limited to 'net/bridge/br_input.c')
| -rw-r--r-- | net/bridge/br_input.c | 121 |
1 files changed, 81 insertions, 40 deletions
diff --git a/net/bridge/br_input.c b/net/bridge/br_input.c index 5ea7e56119c1..8944ceb47fe9 100644 --- a/net/bridge/br_input.c +++ b/net/bridge/br_input.c @@ -1,14 +1,10 @@ +// SPDX-License-Identifier: GPL-2.0-or-later /* * Handle incoming frames * Linux ethernet bridge * * Authors: * Lennert Buytenhek <buytenh@gnu.org> - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation; either version - * 2 of the License, or (at your option) any later version. */ #include <linux/slab.h> @@ -16,6 +12,9 @@ #include <linux/netdevice.h> #include <linux/etherdevice.h> #include <linux/netfilter_bridge.h> +#ifdef CONFIG_NETFILTER_FAMILY_BRIDGE +#include <net/netfilter/nf_queue.h> +#endif #include <linux/neighbour.h> #include <net/arp.h> #include <linux/export.h> @@ -23,10 +22,6 @@ #include "br_private.h" #include "br_private_tunnel.h" -/* Hook for brouter */ -br_should_route_hook_t __rcu *br_should_route_hook __read_mostly; -EXPORT_SYMBOL(br_should_route_hook); - static int br_netif_receive_skb(struct net *net, struct sock *sk, struct sk_buff *skb) { @@ -79,7 +74,6 @@ int br_handle_frame_finish(struct net *net, struct sock *sk, struct sk_buff *skb struct net_bridge_fdb_entry *dst = NULL; struct net_bridge_mdb_entry *mdst; bool local_rcv, mcast_hit = false; - const unsigned char *dest; struct net_bridge *br; u16 vid = 0; @@ -94,13 +88,12 @@ int br_handle_frame_finish(struct net *net, struct sock *sk, struct sk_buff *skb /* insert into forwarding database after filtering to avoid spoofing */ br = p->br; if (p->flags & BR_LEARNING) - br_fdb_update(br, p, eth_hdr(skb)->h_source, vid, false); + br_fdb_update(br, p, eth_hdr(skb)->h_source, vid, 0); local_rcv = !!(br->dev->flags & IFF_PROMISC); - dest = eth_hdr(skb)->h_dest; - if (is_multicast_ether_addr(dest)) { + if (is_multicast_ether_addr(eth_hdr(skb)->h_dest)) { /* by definition the broadcast is also a multicast address */ - if (is_broadcast_ether_addr(dest)) { + if (is_broadcast_ether_addr(eth_hdr(skb)->h_dest)) { pkt_type = BR_PKT_BROADCAST; local_rcv = true; } else { @@ -150,7 +143,7 @@ int br_handle_frame_finish(struct net *net, struct sock *sk, struct sk_buff *skb } break; case BR_PKT_UNICAST: - dst = br_fdb_find_rcu(br, dest, vid); + dst = br_fdb_find_rcu(br, eth_hdr(skb)->h_dest, vid); default: break; } @@ -158,7 +151,7 @@ int br_handle_frame_finish(struct net *net, struct sock *sk, struct sk_buff *skb if (dst) { unsigned long now = jiffies; - if (dst->is_local) + if (test_bit(BR_FDB_LOCAL, &dst->flags)) return br_pass_frame_up(skb); if (now != dst->used) @@ -189,21 +182,72 @@ static void __br_handle_local_finish(struct sk_buff *skb) /* check if vlan is allowed, to avoid spoofing */ if ((p->flags & BR_LEARNING) && + nbp_state_should_learn(p) && !br_opt_get(p->br, BROPT_NO_LL_LEARN) && br_should_learn(p, skb, &vid)) - br_fdb_update(p->br, p, eth_hdr(skb)->h_source, vid, false); + br_fdb_update(p->br, p, eth_hdr(skb)->h_source, vid, 0); } /* note: already called with rcu_read_lock */ static int br_handle_local_finish(struct net *net, struct sock *sk, struct sk_buff *skb) { - struct net_bridge_port *p = br_port_get_rcu(skb->dev); - __br_handle_local_finish(skb); - BR_INPUT_SKB_CB(skb)->brdev = p->br->dev; - br_pass_frame_up(skb); - return 0; + /* return 1 to signal the okfn() was called so it's ok to use the skb */ + return 1; +} + +static int nf_hook_bridge_pre(struct sk_buff *skb, struct sk_buff **pskb) +{ +#ifdef CONFIG_NETFILTER_FAMILY_BRIDGE + struct nf_hook_entries *e = NULL; + struct nf_hook_state state; + unsigned int verdict, i; + struct net *net; + int ret; + + net = dev_net(skb->dev); +#ifdef HAVE_JUMP_LABEL + if (!static_key_false(&nf_hooks_needed[NFPROTO_BRIDGE][NF_BR_PRE_ROUTING])) + goto frame_finish; +#endif + + e = rcu_dereference(net->nf.hooks_bridge[NF_BR_PRE_ROUTING]); + if (!e) + goto frame_finish; + + nf_hook_state_init(&state, NF_BR_PRE_ROUTING, + NFPROTO_BRIDGE, skb->dev, NULL, NULL, + net, br_handle_frame_finish); + + for (i = 0; i < e->num_hook_entries; i++) { + verdict = nf_hook_entry_hookfn(&e->hooks[i], skb, &state); + switch (verdict & NF_VERDICT_MASK) { + case NF_ACCEPT: + if (BR_INPUT_SKB_CB(skb)->br_netfilter_broute) { + *pskb = skb; + return RX_HANDLER_PASS; + } + break; + case NF_DROP: + kfree_skb(skb); + return RX_HANDLER_CONSUMED; + case NF_QUEUE: + ret = nf_queue(skb, &state, i, verdict); + if (ret == 1) + continue; + return RX_HANDLER_CONSUMED; + default: /* STOLEN */ + return RX_HANDLER_CONSUMED; + } + } +frame_finish: + net = dev_net(skb->dev); + br_handle_frame_finish(net, NULL, skb); +#else + br_handle_frame_finish(dev_net(skb->dev), NULL, skb); +#endif + return RX_HANDLER_CONSUMED; } /* @@ -215,7 +259,6 @@ rx_handler_result_t br_handle_frame(struct sk_buff **pskb) struct net_bridge_port *p; struct sk_buff *skb = *pskb; const unsigned char *dest = eth_hdr(skb)->h_dest; - br_should_route_hook_t *rhook; if (unlikely(skb->pkt_type == PACKET_LOOPBACK)) return RX_HANDLER_PASS; @@ -227,6 +270,8 @@ rx_handler_result_t br_handle_frame(struct sk_buff **pskb) if (!skb) return RX_HANDLER_CONSUMED; + memset(skb->cb, 0, sizeof(struct br_input_skb_cb)); + p = br_port_get_rcu(skb->dev); if (p->flags & BR_VLAN_TUNNEL) { if (br_handle_ingress_vlan_tunnel(skb, p, @@ -280,32 +325,28 @@ rx_handler_result_t br_handle_frame(struct sk_buff **pskb) goto forward; } - /* Deliver packet to local host only */ - NF_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_IN, dev_net(skb->dev), - NULL, skb, skb->dev, NULL, br_handle_local_finish); - return RX_HANDLER_CONSUMED; + /* The else clause should be hit when nf_hook(): + * - returns < 0 (drop/error) + * - returns = 0 (stolen/nf_queue) + * Thus return 1 from the okfn() to signal the skb is ok to pass + */ + if (NF_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_IN, + dev_net(skb->dev), NULL, skb, skb->dev, NULL, + br_handle_local_finish) == 1) { + return RX_HANDLER_PASS; + } else { + return RX_HANDLER_CONSUMED; + } } forward: switch (p->state) { case BR_STATE_FORWARDING: - rhook = rcu_dereference(br_should_route_hook); - if (rhook) { - if ((*rhook)(skb)) { - *pskb = skb; - return RX_HANDLER_PASS; - } - dest = eth_hdr(skb)->h_dest; - } - /* fall through */ case BR_STATE_LEARNING: if (ether_addr_equal(p->br->dev->dev_addr, dest)) skb->pkt_type = PACKET_HOST; - NF_HOOK(NFPROTO_BRIDGE, NF_BR_PRE_ROUTING, - dev_net(skb->dev), NULL, skb, skb->dev, NULL, - br_handle_frame_finish); - break; + return nf_hook_bridge_pre(skb, pskb); default: drop: kfree_skb(skb); |
