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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/net/bridge/br_input.c
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/net/bridge/br_input.c')
-rw-r--r--kernel/net/bridge/br_input.c315
1 files changed, 315 insertions, 0 deletions
diff --git a/kernel/net/bridge/br_input.c b/kernel/net/bridge/br_input.c
new file mode 100644
index 000000000..f921a5dce
--- /dev/null
+++ b/kernel/net/bridge/br_input.c
@@ -0,0 +1,315 @@
+/*
+ * 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>
+#include <linux/kernel.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/netfilter_bridge.h>
+#include <linux/neighbour.h>
+#include <net/arp.h>
+#include <linux/export.h>
+#include <linux/rculist.h>
+#include "br_private.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_pass_frame_up(struct sk_buff *skb)
+{
+ struct net_device *indev, *brdev = BR_INPUT_SKB_CB(skb)->brdev;
+ struct net_bridge *br = netdev_priv(brdev);
+ struct pcpu_sw_netstats *brstats = this_cpu_ptr(br->stats);
+ struct net_port_vlans *pv;
+
+ u64_stats_update_begin(&brstats->syncp);
+ brstats->rx_packets++;
+ brstats->rx_bytes += skb->len;
+ u64_stats_update_end(&brstats->syncp);
+
+ /* Bridge is just like any other port. Make sure the
+ * packet is allowed except in promisc modue when someone
+ * may be running packet capture.
+ */
+ pv = br_get_vlan_info(br);
+ if (!(brdev->flags & IFF_PROMISC) &&
+ !br_allowed_egress(br, pv, skb)) {
+ kfree_skb(skb);
+ return NET_RX_DROP;
+ }
+
+ indev = skb->dev;
+ skb->dev = brdev;
+ skb = br_handle_vlan(br, pv, skb);
+ if (!skb)
+ return NET_RX_DROP;
+
+ return NF_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_IN, NULL, skb,
+ indev, NULL,
+ netif_receive_skb_sk);
+}
+
+static void br_do_proxy_arp(struct sk_buff *skb, struct net_bridge *br,
+ u16 vid, struct net_bridge_port *p)
+{
+ struct net_device *dev = br->dev;
+ struct neighbour *n;
+ struct arphdr *parp;
+ u8 *arpptr, *sha;
+ __be32 sip, tip;
+
+ BR_INPUT_SKB_CB(skb)->proxyarp_replied = false;
+
+ if (dev->flags & IFF_NOARP)
+ return;
+
+ if (!pskb_may_pull(skb, arp_hdr_len(dev))) {
+ dev->stats.tx_dropped++;
+ return;
+ }
+ parp = arp_hdr(skb);
+
+ if (parp->ar_pro != htons(ETH_P_IP) ||
+ parp->ar_op != htons(ARPOP_REQUEST) ||
+ parp->ar_hln != dev->addr_len ||
+ parp->ar_pln != 4)
+ return;
+
+ arpptr = (u8 *)parp + sizeof(struct arphdr);
+ sha = arpptr;
+ arpptr += dev->addr_len; /* sha */
+ memcpy(&sip, arpptr, sizeof(sip));
+ arpptr += sizeof(sip);
+ arpptr += dev->addr_len; /* tha */
+ memcpy(&tip, arpptr, sizeof(tip));
+
+ if (ipv4_is_loopback(tip) ||
+ ipv4_is_multicast(tip))
+ return;
+
+ n = neigh_lookup(&arp_tbl, &tip, dev);
+ if (n) {
+ struct net_bridge_fdb_entry *f;
+
+ if (!(n->nud_state & NUD_VALID)) {
+ neigh_release(n);
+ return;
+ }
+
+ f = __br_fdb_get(br, n->ha, vid);
+ if (f && ((p->flags & BR_PROXYARP) ||
+ (f->dst && (f->dst->flags & BR_PROXYARP_WIFI)))) {
+ arp_send(ARPOP_REPLY, ETH_P_ARP, sip, skb->dev, tip,
+ sha, n->ha, sha);
+ BR_INPUT_SKB_CB(skb)->proxyarp_replied = true;
+ }
+
+ neigh_release(n);
+ }
+}
+
+/* note: already called with rcu_read_lock */
+int br_handle_frame_finish(struct sock *sk, struct sk_buff *skb)
+{
+ const unsigned char *dest = eth_hdr(skb)->h_dest;
+ struct net_bridge_port *p = br_port_get_rcu(skb->dev);
+ struct net_bridge *br;
+ struct net_bridge_fdb_entry *dst;
+ struct net_bridge_mdb_entry *mdst;
+ struct sk_buff *skb2;
+ bool unicast = true;
+ u16 vid = 0;
+
+ if (!p || p->state == BR_STATE_DISABLED)
+ goto drop;
+
+ if (!br_allowed_ingress(p->br, nbp_get_vlan_info(p), skb, &vid))
+ goto out;
+
+ /* 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);
+
+ if (!is_broadcast_ether_addr(dest) && is_multicast_ether_addr(dest) &&
+ br_multicast_rcv(br, p, skb, vid))
+ goto drop;
+
+ if (p->state == BR_STATE_LEARNING)
+ goto drop;
+
+ BR_INPUT_SKB_CB(skb)->brdev = br->dev;
+
+ /* The packet skb2 goes to the local host (NULL to skip). */
+ skb2 = NULL;
+
+ if (br->dev->flags & IFF_PROMISC)
+ skb2 = skb;
+
+ dst = NULL;
+
+ if (IS_ENABLED(CONFIG_INET) && skb->protocol == htons(ETH_P_ARP))
+ br_do_proxy_arp(skb, br, vid, p);
+
+ if (is_broadcast_ether_addr(dest)) {
+ skb2 = skb;
+ unicast = false;
+ } else if (is_multicast_ether_addr(dest)) {
+ mdst = br_mdb_get(br, skb, vid);
+ if ((mdst || BR_INPUT_SKB_CB_MROUTERS_ONLY(skb)) &&
+ br_multicast_querier_exists(br, eth_hdr(skb))) {
+ if ((mdst && mdst->mglist) ||
+ br_multicast_is_router(br))
+ skb2 = skb;
+ br_multicast_forward(mdst, skb, skb2);
+ skb = NULL;
+ if (!skb2)
+ goto out;
+ } else
+ skb2 = skb;
+
+ unicast = false;
+ br->dev->stats.multicast++;
+ } else if ((dst = __br_fdb_get(br, dest, vid)) &&
+ dst->is_local) {
+ skb2 = skb;
+ /* Do not forward the packet since it's local. */
+ skb = NULL;
+ }
+
+ if (skb) {
+ if (dst) {
+ dst->used = jiffies;
+ br_forward(dst->dst, skb, skb2);
+ } else
+ br_flood_forward(br, skb, skb2, unicast);
+ }
+
+ if (skb2)
+ return br_pass_frame_up(skb2);
+
+out:
+ return 0;
+drop:
+ kfree_skb(skb);
+ goto out;
+}
+EXPORT_SYMBOL_GPL(br_handle_frame_finish);
+
+/* note: already called with rcu_read_lock */
+static int br_handle_local_finish(struct sock *sk, struct sk_buff *skb)
+{
+ struct net_bridge_port *p = br_port_get_rcu(skb->dev);
+ u16 vid = 0;
+
+ /* check if vlan is allowed, to avoid spoofing */
+ if (p->flags & BR_LEARNING && br_should_learn(p, skb, &vid))
+ br_fdb_update(p->br, p, eth_hdr(skb)->h_source, vid, false);
+ return 0; /* process further */
+}
+
+/*
+ * Return NULL if skb is handled
+ * note: already called with rcu_read_lock
+ */
+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;
+
+ if (!is_valid_ether_addr(eth_hdr(skb)->h_source))
+ goto drop;
+
+ skb = skb_share_check(skb, GFP_ATOMIC);
+ if (!skb)
+ return RX_HANDLER_CONSUMED;
+
+ p = br_port_get_rcu(skb->dev);
+
+ if (unlikely(is_link_local_ether_addr(dest))) {
+ u16 fwd_mask = p->br->group_fwd_mask_required;
+
+ /*
+ * See IEEE 802.1D Table 7-10 Reserved addresses
+ *
+ * Assignment Value
+ * Bridge Group Address 01-80-C2-00-00-00
+ * (MAC Control) 802.3 01-80-C2-00-00-01
+ * (Link Aggregation) 802.3 01-80-C2-00-00-02
+ * 802.1X PAE address 01-80-C2-00-00-03
+ *
+ * 802.1AB LLDP 01-80-C2-00-00-0E
+ *
+ * Others reserved for future standardization
+ */
+ switch (dest[5]) {
+ case 0x00: /* Bridge Group Address */
+ /* If STP is turned off,
+ then must forward to keep loop detection */
+ if (p->br->stp_enabled == BR_NO_STP ||
+ fwd_mask & (1u << dest[5]))
+ goto forward;
+ break;
+
+ case 0x01: /* IEEE MAC (Pause) */
+ goto drop;
+
+ default:
+ /* Allow selective forwarding for most other protocols */
+ fwd_mask |= p->br->group_fwd_mask;
+ if (fwd_mask & (1u << dest[5]))
+ goto forward;
+ }
+
+ /* Deliver packet to local host only */
+ if (NF_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_IN, NULL, skb,
+ skb->dev, NULL, br_handle_local_finish)) {
+ return RX_HANDLER_CONSUMED; /* consumed by filter */
+ } else {
+ *pskb = skb;
+ return RX_HANDLER_PASS; /* continue processing */
+ }
+ }
+
+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, NULL, skb,
+ skb->dev, NULL,
+ br_handle_frame_finish);
+ break;
+ default:
+drop:
+ kfree_skb(skb);
+ }
+ return RX_HANDLER_CONSUMED;
+}