dm: dm-zoned: use __bio_add_page for adding single metadata page
[linux-block.git] / net / bridge / br_forward.c
CommitLineData
2874c5fd 1// SPDX-License-Identifier: GPL-2.0-or-later
1da177e4
LT
2/*
3 * Forwarding decision
4 * Linux ethernet bridge
5 *
6 * Authors:
7 * Lennert Buytenhek <buytenh@gnu.org>
1da177e4
LT
8 */
9
025d89c2 10#include <linux/err.h>
5a0e3ad6 11#include <linux/slab.h>
1da177e4
LT
12#include <linux/kernel.h>
13#include <linux/netdevice.h>
c06ee961 14#include <linux/netpoll.h>
1da177e4 15#include <linux/skbuff.h>
85ca719e 16#include <linux/if_vlan.h>
1da177e4
LT
17#include <linux/netfilter_bridge.h>
18#include "br_private.h"
19
1a81a2e0 20/* Don't forward packets to originating port or forwarding disabled */
9d6f229f 21static inline int should_deliver(const struct net_bridge_port *p,
1da177e4
LT
22 const struct sk_buff *skb)
23{
2594e906
NA
24 struct net_bridge_vlan_group *vg;
25
907b1e6e 26 vg = nbp_vlan_group_rcu(p);
a97bfc1d 27 return ((p->flags & BR_HAIRPIN_MODE) || skb->dev != p->dev) &&
ac0e932d 28 p->state == BR_STATE_FORWARDING && br_allowed_egress(vg, skb) &&
7d850abd
NA
29 nbp_switchdev_allowed_egress(p, skb) &&
30 !br_skb_isolated(p, skb);
1da177e4
LT
31}
32
0c4b51f0 33int br_dev_queue_push_xmit(struct net *net, struct sock *sk, struct sk_buff *skb)
1da177e4 34{
28c1382f 35 skb_push(skb, ETH_HLEN);
df356d5e
TM
36 if (!is_skb_forwardable(skb->dev, skb))
37 goto drop;
38
df356d5e 39 br_drop_fake_rtable(skb);
df356d5e
TM
40
41 if (skb->ip_summed == CHECKSUM_PARTIAL &&
a98c0c47 42 eth_type_vlan(skb->protocol)) {
df356d5e
TM
43 int depth;
44
4063384e 45 if (!vlan_get_protocol_and_depth(skb, skb->protocol, &depth))
df356d5e
TM
46 goto drop;
47
48 skb_set_network_header(skb, depth);
1da177e4
LT
49 }
50
c5381154 51 br_switchdev_frame_set_offload_fwd_mark(skb);
47211192 52
df356d5e
TM
53 dev_queue_xmit(skb);
54
55 return 0;
56
57drop:
58 kfree_skb(skb);
1da177e4
LT
59 return 0;
60}
34666d46 61EXPORT_SYMBOL_GPL(br_dev_queue_push_xmit);
1da177e4 62
0c4b51f0 63int br_forward_finish(struct net *net, struct sock *sk, struct sk_buff *skb)
1da177e4 64{
de799101 65 skb_clear_tstamp(skb);
29a26a56
EB
66 return NF_HOOK(NFPROTO_BRIDGE, NF_BR_POST_ROUTING,
67 net, sk, skb, NULL, skb->dev,
9ef513be 68 br_dev_queue_push_xmit);
1da177e4 69
1da177e4 70}
34666d46 71EXPORT_SYMBOL_GPL(br_forward_finish);
1da177e4 72
37b090e6
NA
73static void __br_forward(const struct net_bridge_port *to,
74 struct sk_buff *skb, bool local_orig)
1da177e4 75{
2594e906 76 struct net_bridge_vlan_group *vg;
37b090e6
NA
77 struct net_device *indev;
78 struct net *net;
79 int br_hook;
2594e906 80
47211192
TW
81 /* Mark the skb for forwarding offload early so that br_handle_vlan()
82 * can know whether to pop the VLAN header on egress or keep it.
83 */
84 nbp_switchdev_frame_mark_tx_fwd_offload(to, skb);
85
907b1e6e 86 vg = nbp_vlan_group_rcu(to);
11538d03 87 skb = br_handle_vlan(to->br, to, vg, skb);
78851988
VY
88 if (!skb)
89 return;
90
37b090e6 91 indev = skb->dev;
1da177e4 92 skb->dev = to->dev;
37b090e6
NA
93 if (!local_orig) {
94 if (skb_warn_if_lro(skb)) {
91d2c34a 95 kfree_skb(skb);
37b090e6 96 return;
91d2c34a 97 }
37b090e6
NA
98 br_hook = NF_BR_FORWARD;
99 skb_forward_csum(skb);
100 net = dev_net(indev);
101 } else {
102 if (unlikely(netpoll_tx_running(to->br->dev))) {
28c1382f
YW
103 skb_push(skb, ETH_HLEN);
104 if (!is_skb_forwardable(skb->dev, skb))
37b090e6 105 kfree_skb(skb);
28c1382f 106 else
37b090e6 107 br_netpoll_send_skb(to, skb);
37b090e6
NA
108 return;
109 }
110 br_hook = NF_BR_LOCAL_OUT;
111 net = dev_net(skb->dev);
112 indev = NULL;
91d2c34a
HX
113 }
114
37b090e6
NA
115 NF_HOOK(NFPROTO_BRIDGE, br_hook,
116 net, NULL, skb, indev, skb->dev,
713aefa3 117 br_forward_finish);
1da177e4
LT
118}
119
37b090e6
NA
120static int deliver_clone(const struct net_bridge_port *prev,
121 struct sk_buff *skb, bool local_orig)
1da177e4 122{
37b090e6 123 struct net_device *dev = BR_INPUT_SKB_CB(skb)->brdev;
1da177e4 124
37b090e6
NA
125 skb = skb_clone(skb, GFP_ATOMIC);
126 if (!skb) {
127 dev->stats.tx_dropped++;
128 return -ENOMEM;
1da177e4
LT
129 }
130
37b090e6
NA
131 __br_forward(prev, skb, local_orig);
132 return 0;
1da177e4
LT
133}
134
37b090e6
NA
135/**
136 * br_forward - forward a packet to a specific port
137 * @to: destination port
138 * @skb: packet being forwarded
139 * @local_rcv: packet will be received locally after forwarding
140 * @local_orig: packet is locally originated
141 *
142 * Should be called with rcu_read_lock.
143 */
144void br_forward(const struct net_bridge_port *to,
145 struct sk_buff *skb, bool local_rcv, bool local_orig)
1da177e4 146{
2756f68c
NA
147 if (unlikely(!to))
148 goto out;
149
150 /* redirect to backup link if the destination port is down */
151 if (rcu_access_pointer(to->backup_port) && !netif_carrier_ok(to->dev)) {
152 struct net_bridge_port *backup_port;
153
154 backup_port = rcu_dereference(to->backup_port);
155 if (unlikely(!backup_port))
156 goto out;
157 to = backup_port;
158 }
159
160 if (should_deliver(to, skb)) {
b35c5f63 161 if (local_rcv)
37b090e6 162 deliver_clone(to, skb, local_orig);
7f7708f0 163 else
37b090e6 164 __br_forward(to, skb, local_orig);
1da177e4
LT
165 return;
166 }
167
2756f68c 168out:
b35c5f63 169 if (!local_rcv)
7f7708f0 170 kfree_skb(skb);
1da177e4 171}
37b090e6 172EXPORT_SYMBOL_GPL(br_forward);
025d89c2
HX
173
174static struct net_bridge_port *maybe_deliver(
175 struct net_bridge_port *prev, struct net_bridge_port *p,
37b090e6 176 struct sk_buff *skb, bool local_orig)
025d89c2 177{
847d44ef 178 u8 igmp_type = br_multicast_igmp_type(skb);
025d89c2
HX
179 int err;
180
181 if (!should_deliver(p, skb))
182 return prev;
183
47211192
TW
184 nbp_switchdev_frame_mark_tx_fwd_to_hwdom(p, skb);
185
025d89c2
HX
186 if (!prev)
187 goto out;
188
37b090e6 189 err = deliver_clone(prev, skb, local_orig);
025d89c2
HX
190 if (err)
191 return ERR_PTR(err);
025d89c2 192out:
847d44ef
PNA
193 br_multicast_count(p->br, p, skb, igmp_type, BR_MCAST_DIR_TX);
194
025d89c2
HX
195 return p;
196}
197
37b090e6
NA
198/* called under rcu_read_lock */
199void br_flood(struct net_bridge *br, struct sk_buff *skb,
e408336a
IS
200 enum br_pkt_type pkt_type, bool local_rcv, bool local_orig,
201 u16 vid)
1da177e4 202{
37b090e6 203 struct net_bridge_port *prev = NULL;
1080ab95 204 struct net_bridge_port *p;
1da177e4 205
1da177e4 206 list_for_each_entry_rcu(p, &br->port_list, list) {
99f906e9
MM
207 /* Do not flood unicast traffic to ports that turn it off, nor
208 * other traffic if flood off, except for traffic we originate
209 */
210 switch (pkt_type) {
211 case BR_PKT_UNICAST:
212 if (!(p->flags & BR_FLOOD))
213 continue;
214 break;
215 case BR_PKT_MULTICAST:
216 if (!(p->flags & BR_MCAST_FLOOD) && skb->dev != br->dev)
217 continue;
218 break;
219 case BR_PKT_BROADCAST:
220 if (!(p->flags & BR_BCAST_FLOOD) && skb->dev != br->dev)
221 continue;
222 break;
223 }
95850116
KP
224
225 /* Do not flood to ports that enable proxy ARP */
226 if (p->flags & BR_PROXYARP)
227 continue;
013a7ce8 228 if (BR_INPUT_SKB_CB(skb)->proxyarp_replied &&
3aca683e
IS
229 ((p->flags & BR_PROXYARP_WIFI) ||
230 br_is_neigh_suppress_enabled(p, vid)))
842a9ae0 231 continue;
95850116 232
37b090e6 233 prev = maybe_deliver(prev, p, skb, local_orig);
025d89c2
HX
234 if (IS_ERR(prev))
235 goto out;
1da177e4
LT
236 }
237
b33084be
HX
238 if (!prev)
239 goto out;
240
b35c5f63 241 if (local_rcv)
37b090e6 242 deliver_clone(prev, skb, local_orig);
025d89c2 243 else
37b090e6 244 __br_forward(prev, skb, local_orig);
b33084be 245 return;
1da177e4 246
b33084be 247out:
b35c5f63 248 if (!local_rcv)
b33084be 249 kfree_skb(skb);
1da177e4
LT
250}
251
5cb5e947 252#ifdef CONFIG_BRIDGE_IGMP_SNOOPING
5b9d6b15
AB
253static void maybe_deliver_addr(struct net_bridge_port *p, struct sk_buff *skb,
254 const unsigned char *addr, bool local_orig)
255{
256 struct net_device *dev = BR_INPUT_SKB_CB(skb)->brdev;
257 const unsigned char *src = eth_hdr(skb)->h_source;
258
259 if (!should_deliver(p, skb))
260 return;
261
262 /* Even with hairpin, no soliloquies - prevent breaking IPv6 DAD */
263 if (skb->dev == p->dev && ether_addr_equal(src, addr))
264 return;
265
266 skb = skb_copy(skb, GFP_ATOMIC);
267 if (!skb) {
268 dev->stats.tx_dropped++;
269 return;
270 }
271
272 if (!is_broadcast_ether_addr(addr))
273 memcpy(eth_hdr(skb)->h_dest, addr, ETH_ALEN);
274
275 __br_forward(p, skb, local_orig);
276}
277
5cb5e947 278/* called with rcu_read_lock */
37b090e6
NA
279void br_multicast_flood(struct net_bridge_mdb_entry *mdst,
280 struct sk_buff *skb,
adc47037 281 struct net_bridge_mcast *brmctx,
37b090e6 282 bool local_rcv, bool local_orig)
5cb5e947 283{
afe0159d 284 struct net_bridge_port *prev = NULL;
5cb5e947 285 struct net_bridge_port_group *p;
36cfec73 286 bool allow_mode_include = true;
5cb5e947
HX
287 struct hlist_node *rp;
288
adc47037 289 rp = br_multicast_get_first_rport_node(brmctx, skb);
44ebb081 290
36cfec73
NA
291 if (mdst) {
292 p = rcu_dereference(mdst->ports);
adc47037 293 if (br_multicast_should_handle_mode(brmctx, mdst->addr.proto) &&
36cfec73
NA
294 br_multicast_is_star_g(&mdst->addr))
295 allow_mode_include = false;
296 } else {
297 p = NULL;
298 }
299
5cb5e947 300 while (p || rp) {
afe0159d 301 struct net_bridge_port *port, *lport, *rport;
302
085b53c8 303 lport = p ? p->key.port : NULL;
44ebb081 304 rport = br_multicast_rport_from_node_skb(rp, skb);
5cb5e947 305
6db6f0ea
FF
306 if ((unsigned long)lport > (unsigned long)rport) {
307 port = lport;
308
309 if (port->flags & BR_MULTICAST_TO_UNICAST) {
310 maybe_deliver_addr(lport, skb, p->eth_addr,
311 local_orig);
312 goto delivered;
313 }
36cfec73
NA
314 if ((!allow_mode_include &&
315 p->filter_mode == MCAST_INCLUDE) ||
316 (p->flags & MDB_PG_FLAGS_BLOCKED))
317 goto delivered;
6db6f0ea
FF
318 } else {
319 port = rport;
320 }
5cb5e947 321
37b090e6 322 prev = maybe_deliver(prev, port, skb, local_orig);
5cb5e947
HX
323 if (IS_ERR(prev))
324 goto out;
847d44ef 325delivered:
5cb5e947 326 if ((unsigned long)lport >= (unsigned long)port)
83f6a740 327 p = rcu_dereference(p->next);
5cb5e947 328 if ((unsigned long)rport >= (unsigned long)port)
e8051688 329 rp = rcu_dereference(hlist_next_rcu(rp));
5cb5e947
HX
330 }
331
332 if (!prev)
333 goto out;
334
b35c5f63 335 if (local_rcv)
37b090e6 336 deliver_clone(prev, skb, local_orig);
5cb5e947 337 else
37b090e6 338 __br_forward(prev, skb, local_orig);
5cb5e947
HX
339 return;
340
341out:
b35c5f63 342 if (!local_rcv)
5cb5e947
HX
343 kfree_skb(skb);
344}
5cb5e947 345#endif