#ifndef _BR_NETFILTER_H_
#define _BR_NETFILTER_H_
+#include "../../../net/bridge/br_private.h"
+
+static inline struct nf_bridge_info *nf_bridge_alloc(struct sk_buff *skb)
+{
+ skb->nf_bridge = kzalloc(sizeof(struct nf_bridge_info), GFP_ATOMIC);
+
+ if (likely(skb->nf_bridge))
+ atomic_set(&(skb->nf_bridge->use), 1);
+
+ return skb->nf_bridge;
+}
+
+void nf_bridge_update_protocol(struct sk_buff *skb);
+
+static inline struct nf_bridge_info *
+nf_bridge_info_get(const struct sk_buff *skb)
+{
+ return skb->nf_bridge;
+}
+
+unsigned int nf_bridge_encap_header_len(const struct sk_buff *skb);
+
+static inline void nf_bridge_push_encap_header(struct sk_buff *skb)
+{
+ unsigned int len = nf_bridge_encap_header_len(skb);
+
+ skb_push(skb, len);
+ skb->network_header -= len;
+}
+
+int br_nf_pre_routing_finish_bridge(struct sock *sk, struct sk_buff *skb);
+
+static inline struct rtable *bridge_parent_rtable(const struct net_device *dev)
+{
+ struct net_bridge_port *port;
+
+ port = br_port_get_rcu(dev);
+ return port ? &port->br->fake_rtable : NULL;
+}
+
+struct net_device *setup_pre_routing(struct sk_buff *skb);
void br_netfilter_enable(void);
+#if IS_ENABLED(CONFIG_IPV6)
+int br_validate_ipv6(struct sk_buff *skb);
+unsigned int br_nf_pre_routing_ipv6(const struct nf_hook_ops *ops,
+ struct sk_buff *skb,
+ const struct nf_hook_state *state);
+#else
+static inline int br_validate_ipv6(struct sk_buff *skb)
+{
+ return -1;
+}
+
+static inline unsigned int
+br_nf_pre_routing_ipv6(const struct nf_hook_ops *ops, struct sk_buff *skb,
+ const struct nf_hook_state *state)
+{
+ return NF_DROP;
+}
+#endif
+
#endif /* _BR_NETFILTER_H_ */
bridge-$(subst m,y,$(CONFIG_BRIDGE_NETFILTER)) += br_nf_core.o
br_netfilter-y := br_netfilter_hooks.o
+br_netfilter-$(subst m,y,$(CONFIG_IPV6)) += br_netfilter_ipv6.o
obj-$(CONFIG_BRIDGE_NETFILTER) += br_netfilter.o
bridge-$(CONFIG_BRIDGE_IGMP_SNOOPING) += br_multicast.o br_mdb.o
static DEFINE_PER_CPU(struct brnf_frag_data, brnf_frag_data_storage);
#endif
-static struct nf_bridge_info *nf_bridge_info_get(const struct sk_buff *skb)
-{
- return skb->nf_bridge;
-}
-
static void nf_bridge_info_free(struct sk_buff *skb)
{
if (skb->nf_bridge) {
}
}
-static inline struct rtable *bridge_parent_rtable(const struct net_device *dev)
-{
- struct net_bridge_port *port;
-
- port = br_port_get_rcu(dev);
- return port ? &port->br->fake_rtable : NULL;
-}
-
static inline struct net_device *bridge_parent(const struct net_device *dev)
{
struct net_bridge_port *port;
return port ? port->br->dev : NULL;
}
-static inline struct nf_bridge_info *nf_bridge_alloc(struct sk_buff *skb)
-{
- skb->nf_bridge = kzalloc(sizeof(struct nf_bridge_info), GFP_ATOMIC);
- if (likely(skb->nf_bridge))
- atomic_set(&(skb->nf_bridge->use), 1);
-
- return skb->nf_bridge;
-}
-
static inline struct nf_bridge_info *nf_bridge_unshare(struct sk_buff *skb)
{
struct nf_bridge_info *nf_bridge = skb->nf_bridge;
return nf_bridge;
}
-static unsigned int nf_bridge_encap_header_len(const struct sk_buff *skb)
+unsigned int nf_bridge_encap_header_len(const struct sk_buff *skb)
{
switch (skb->protocol) {
case __cpu_to_be16(ETH_P_8021Q):
}
}
-static inline void nf_bridge_push_encap_header(struct sk_buff *skb)
-{
- unsigned int len = nf_bridge_encap_header_len(skb);
-
- skb_push(skb, len);
- skb->network_header -= len;
-}
-
static inline void nf_bridge_pull_encap_header(struct sk_buff *skb)
{
unsigned int len = nf_bridge_encap_header_len(skb);
return -1;
}
-/* We only check the length. A bridge shouldn't do any hop-by-hop stuff
- * anyway
- */
-static int check_hbh_len(struct sk_buff *skb)
-{
- unsigned char *raw = (u8 *)(ipv6_hdr(skb) + 1);
- u32 pkt_len;
- const unsigned char *nh = skb_network_header(skb);
- int off = raw - nh;
- int len = (raw[1] + 1) << 3;
-
- if ((raw + len) - skb->data > skb_headlen(skb))
- goto bad;
-
- off += 2;
- len -= 2;
-
- while (len > 0) {
- int optlen = nh[off + 1] + 2;
-
- switch (nh[off]) {
- case IPV6_TLV_PAD1:
- optlen = 1;
- break;
-
- case IPV6_TLV_PADN:
- break;
-
- case IPV6_TLV_JUMBO:
- if (nh[off + 1] != 4 || (off & 3) != 2)
- goto bad;
- pkt_len = ntohl(*(__be32 *)(nh + off + 2));
- if (pkt_len <= IPV6_MAXPLEN ||
- ipv6_hdr(skb)->payload_len)
- goto bad;
- if (pkt_len > skb->len - sizeof(struct ipv6hdr))
- goto bad;
- if (pskb_trim_rcsum(skb,
- pkt_len + sizeof(struct ipv6hdr)))
- goto bad;
- nh = skb_network_header(skb);
- break;
- default:
- if (optlen > len)
- goto bad;
- break;
- }
- off += optlen;
- len -= optlen;
- }
- if (len == 0)
- return 0;
-bad:
- return -1;
-}
-
-/* Equivalent to br_validate_ipv4 for IPv6 */
-static int br_validate_ipv6(struct sk_buff *skb)
-{
- const struct ipv6hdr *hdr;
- struct net_device *dev = skb->dev;
- struct inet6_dev *idev = in6_dev_get(skb->dev);
- u32 pkt_len;
- u8 ip6h_len = sizeof(struct ipv6hdr);
-
- if (!pskb_may_pull(skb, ip6h_len))
- goto inhdr_error;
-
- if (skb->len < ip6h_len)
- goto drop;
-
- hdr = ipv6_hdr(skb);
-
- if (hdr->version != 6)
- goto inhdr_error;
-
- pkt_len = ntohs(hdr->payload_len);
-
- if (pkt_len || hdr->nexthdr != NEXTHDR_HOP) {
- if (pkt_len + ip6h_len > skb->len) {
- IP6_INC_STATS_BH(dev_net(dev), idev,
- IPSTATS_MIB_INTRUNCATEDPKTS);
- goto drop;
- }
- if (pskb_trim_rcsum(skb, pkt_len + ip6h_len)) {
- IP6_INC_STATS_BH(dev_net(dev), idev,
- IPSTATS_MIB_INDISCARDS);
- goto drop;
- }
- }
- if (hdr->nexthdr == NEXTHDR_HOP && check_hbh_len(skb))
- goto drop;
-
- memset(IP6CB(skb), 0, sizeof(struct inet6_skb_parm));
- /* No IP options in IPv6 header; however it should be
- * checked if some next headers need special treatment
- */
- return 0;
-
-inhdr_error:
- IP6_INC_STATS_BH(dev_net(dev), idev, IPSTATS_MIB_INHDRERRORS);
-drop:
- return -1;
-}
-
-static void nf_bridge_update_protocol(struct sk_buff *skb)
+void nf_bridge_update_protocol(struct sk_buff *skb)
{
switch (skb->nf_bridge->orig_proto) {
case BRNF_PROTO_8021Q:
* don't, we use the neighbour framework to find out. In both cases, we make
* sure that br_handle_frame_finish() is called afterwards.
*/
-static int br_nf_pre_routing_finish_bridge(struct sock *sk, struct sk_buff *skb)
+int br_nf_pre_routing_finish_bridge(struct sock *sk, struct sk_buff *skb)
{
struct neighbour *neigh;
struct dst_entry *dst;
return 0;
}
-static bool daddr_was_changed(const struct sk_buff *skb,
- const struct nf_bridge_info *nf_bridge)
+static inline bool
+br_nf_ipv4_daddr_was_changed(const struct sk_buff *skb,
+ const struct nf_bridge_info *nf_bridge)
{
- switch (skb->protocol) {
- case htons(ETH_P_IP):
- return ip_hdr(skb)->daddr != nf_bridge->ipv4_daddr;
- case htons(ETH_P_IPV6):
- return memcmp(&nf_bridge->ipv6_daddr, &ipv6_hdr(skb)->daddr,
- sizeof(ipv6_hdr(skb)->daddr)) != 0;
- default:
- return false;
- }
-}
-
-/* PF_BRIDGE/PRE_ROUTING: Undo the changes made for ip6tables
- * PREROUTING and continue the bridge PRE_ROUTING hook. See comment
- * for br_nf_pre_routing_finish(), same logic is used here but
- * equivalent IPv6 function ip6_route_input() called indirectly.
- */
-static int br_nf_pre_routing_finish_ipv6(struct sock *sk, struct sk_buff *skb)
-{
- struct nf_bridge_info *nf_bridge = nf_bridge_info_get(skb);
- struct rtable *rt;
- struct net_device *dev = skb->dev;
- const struct nf_ipv6_ops *v6ops = nf_get_ipv6_ops();
-
- nf_bridge->frag_max_size = IP6CB(skb)->frag_max_size;
-
- if (nf_bridge->pkt_otherhost) {
- skb->pkt_type = PACKET_OTHERHOST;
- nf_bridge->pkt_otherhost = false;
- }
- nf_bridge->mask &= ~BRNF_NF_BRIDGE_PREROUTING;
- if (daddr_was_changed(skb, nf_bridge)) {
- skb_dst_drop(skb);
- v6ops->route_input(skb);
-
- if (skb_dst(skb)->error) {
- kfree_skb(skb);
- return 0;
- }
-
- if (skb_dst(skb)->dev == dev) {
- skb->dev = nf_bridge->physindev;
- nf_bridge_update_protocol(skb);
- nf_bridge_push_encap_header(skb);
- NF_HOOK_THRESH(NFPROTO_BRIDGE, NF_BR_PRE_ROUTING,
- sk, skb, skb->dev, NULL,
- br_nf_pre_routing_finish_bridge,
- 1);
- return 0;
- }
- ether_addr_copy(eth_hdr(skb)->h_dest, dev->dev_addr);
- skb->pkt_type = PACKET_HOST;
- } else {
- rt = bridge_parent_rtable(nf_bridge->physindev);
- if (!rt) {
- kfree_skb(skb);
- return 0;
- }
- skb_dst_set_noref(skb, &rt->dst);
- }
-
- skb->dev = nf_bridge->physindev;
- nf_bridge_update_protocol(skb);
- nf_bridge_push_encap_header(skb);
- NF_HOOK_THRESH(NFPROTO_BRIDGE, NF_BR_PRE_ROUTING, sk, skb,
- skb->dev, NULL,
- br_handle_frame_finish, 1);
-
- return 0;
+ return ip_hdr(skb)->daddr != nf_bridge->ipv4_daddr;
}
/* This requires some explaining. If DNAT has taken place,
nf_bridge->pkt_otherhost = false;
}
nf_bridge->mask &= ~BRNF_NF_BRIDGE_PREROUTING;
- if (daddr_was_changed(skb, nf_bridge)) {
+ if (br_nf_ipv4_daddr_was_changed(skb, nf_bridge)) {
if ((err = ip_route_input(skb, iph->daddr, iph->saddr, iph->tos, dev))) {
struct in_device *in_dev = __in_dev_get_rcu(dev);
}
/* Some common code for IPv4/IPv6 */
-static struct net_device *setup_pre_routing(struct sk_buff *skb)
+struct net_device *setup_pre_routing(struct sk_buff *skb)
{
struct nf_bridge_info *nf_bridge = nf_bridge_info_get(skb);
return skb->dev;
}
-/* Replicate the checks that IPv6 does on packet reception and pass the packet
- * to ip6tables.
- */
-static unsigned int br_nf_pre_routing_ipv6(const struct nf_hook_ops *ops,
- struct sk_buff *skb,
- const struct nf_hook_state *state)
-{
- struct nf_bridge_info *nf_bridge;
-
- if (br_validate_ipv6(skb))
- return NF_DROP;
-
- nf_bridge_put(skb->nf_bridge);
- if (!nf_bridge_alloc(skb))
- return NF_DROP;
- if (!setup_pre_routing(skb))
- return NF_DROP;
-
- nf_bridge = nf_bridge_info_get(skb);
- nf_bridge->ipv6_daddr = ipv6_hdr(skb)->daddr;
-
- skb->protocol = htons(ETH_P_IPV6);
- NF_HOOK(NFPROTO_IPV6, NF_INET_PRE_ROUTING, state->sk, skb,
- skb->dev, NULL,
- br_nf_pre_routing_finish_ipv6);
-
- return NF_STOLEN;
-}
-
/* Direct IPv6 traffic to br_nf_pre_routing_ipv6.
* Replicate the checks that IPv4 does on packet reception.
* Set skb->dev to the bridge device (i.e. parent of the
--- /dev/null
+/*
+ * Handle firewalling
+ * Linux ethernet bridge
+ *
+ * Authors:
+ * Lennert Buytenhek <buytenh@gnu.org>
+ * Bart De Schuymer <bdschuym@pandora.be>
+ *
+ * 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.
+ *
+ * Lennert dedicates this file to Kerstin Wurdinger.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/ip.h>
+#include <linux/netdevice.h>
+#include <linux/skbuff.h>
+#include <linux/if_arp.h>
+#include <linux/if_ether.h>
+#include <linux/if_vlan.h>
+#include <linux/if_pppox.h>
+#include <linux/ppp_defs.h>
+#include <linux/netfilter_bridge.h>
+#include <linux/netfilter_ipv4.h>
+#include <linux/netfilter_ipv6.h>
+#include <linux/netfilter_arp.h>
+#include <linux/in_route.h>
+#include <linux/inetdevice.h>
+
+#include <net/ip.h>
+#include <net/ipv6.h>
+#include <net/addrconf.h>
+#include <net/route.h>
+#include <net/netfilter/br_netfilter.h>
+
+#include <asm/uaccess.h>
+#include "br_private.h"
+#ifdef CONFIG_SYSCTL
+#include <linux/sysctl.h>
+#endif
+
+/* We only check the length. A bridge shouldn't do any hop-by-hop stuff
+ * anyway
+ */
+static int br_nf_check_hbh_len(struct sk_buff *skb)
+{
+ unsigned char *raw = (u8 *)(ipv6_hdr(skb) + 1);
+ u32 pkt_len;
+ const unsigned char *nh = skb_network_header(skb);
+ int off = raw - nh;
+ int len = (raw[1] + 1) << 3;
+
+ if ((raw + len) - skb->data > skb_headlen(skb))
+ goto bad;
+
+ off += 2;
+ len -= 2;
+
+ while (len > 0) {
+ int optlen = nh[off + 1] + 2;
+
+ switch (nh[off]) {
+ case IPV6_TLV_PAD1:
+ optlen = 1;
+ break;
+
+ case IPV6_TLV_PADN:
+ break;
+
+ case IPV6_TLV_JUMBO:
+ if (nh[off + 1] != 4 || (off & 3) != 2)
+ goto bad;
+ pkt_len = ntohl(*(__be32 *)(nh + off + 2));
+ if (pkt_len <= IPV6_MAXPLEN ||
+ ipv6_hdr(skb)->payload_len)
+ goto bad;
+ if (pkt_len > skb->len - sizeof(struct ipv6hdr))
+ goto bad;
+ if (pskb_trim_rcsum(skb,
+ pkt_len + sizeof(struct ipv6hdr)))
+ goto bad;
+ nh = skb_network_header(skb);
+ break;
+ default:
+ if (optlen > len)
+ goto bad;
+ break;
+ }
+ off += optlen;
+ len -= optlen;
+ }
+ if (len == 0)
+ return 0;
+bad:
+ return -1;
+}
+
+int br_validate_ipv6(struct sk_buff *skb)
+{
+ const struct ipv6hdr *hdr;
+ struct net_device *dev = skb->dev;
+ struct inet6_dev *idev = in6_dev_get(skb->dev);
+ u32 pkt_len;
+ u8 ip6h_len = sizeof(struct ipv6hdr);
+
+ if (!pskb_may_pull(skb, ip6h_len))
+ goto inhdr_error;
+
+ if (skb->len < ip6h_len)
+ goto drop;
+
+ hdr = ipv6_hdr(skb);
+
+ if (hdr->version != 6)
+ goto inhdr_error;
+
+ pkt_len = ntohs(hdr->payload_len);
+
+ if (pkt_len || hdr->nexthdr != NEXTHDR_HOP) {
+ if (pkt_len + ip6h_len > skb->len) {
+ IP6_INC_STATS_BH(dev_net(dev), idev,
+ IPSTATS_MIB_INTRUNCATEDPKTS);
+ goto drop;
+ }
+ if (pskb_trim_rcsum(skb, pkt_len + ip6h_len)) {
+ IP6_INC_STATS_BH(dev_net(dev), idev,
+ IPSTATS_MIB_INDISCARDS);
+ goto drop;
+ }
+ }
+ if (hdr->nexthdr == NEXTHDR_HOP && br_nf_check_hbh_len(skb))
+ goto drop;
+
+ memset(IP6CB(skb), 0, sizeof(struct inet6_skb_parm));
+ /* No IP options in IPv6 header; however it should be
+ * checked if some next headers need special treatment
+ */
+ return 0;
+
+inhdr_error:
+ IP6_INC_STATS_BH(dev_net(dev), idev, IPSTATS_MIB_INHDRERRORS);
+drop:
+ return -1;
+}
+
+static inline bool
+br_nf_ipv6_daddr_was_changed(const struct sk_buff *skb,
+ const struct nf_bridge_info *nf_bridge)
+{
+ return memcmp(&nf_bridge->ipv6_daddr, &ipv6_hdr(skb)->daddr,
+ sizeof(ipv6_hdr(skb)->daddr)) != 0;
+}
+
+/* PF_BRIDGE/PRE_ROUTING: Undo the changes made for ip6tables
+ * PREROUTING and continue the bridge PRE_ROUTING hook. See comment
+ * for br_nf_pre_routing_finish(), same logic is used here but
+ * equivalent IPv6 function ip6_route_input() called indirectly.
+ */
+static int br_nf_pre_routing_finish_ipv6(struct sock *sk, struct sk_buff *skb)
+{
+ struct nf_bridge_info *nf_bridge = nf_bridge_info_get(skb);
+ struct rtable *rt;
+ struct net_device *dev = skb->dev;
+ const struct nf_ipv6_ops *v6ops = nf_get_ipv6_ops();
+
+ nf_bridge->frag_max_size = IP6CB(skb)->frag_max_size;
+
+ if (nf_bridge->pkt_otherhost) {
+ skb->pkt_type = PACKET_OTHERHOST;
+ nf_bridge->pkt_otherhost = false;
+ }
+ nf_bridge->mask &= ~BRNF_NF_BRIDGE_PREROUTING;
+ if (br_nf_ipv6_daddr_was_changed(skb, nf_bridge)) {
+ skb_dst_drop(skb);
+ v6ops->route_input(skb);
+
+ if (skb_dst(skb)->error) {
+ kfree_skb(skb);
+ return 0;
+ }
+
+ if (skb_dst(skb)->dev == dev) {
+ skb->dev = nf_bridge->physindev;
+ nf_bridge_update_protocol(skb);
+ nf_bridge_push_encap_header(skb);
+ NF_HOOK_THRESH(NFPROTO_BRIDGE, NF_BR_PRE_ROUTING,
+ sk, skb, skb->dev, NULL,
+ br_nf_pre_routing_finish_bridge,
+ 1);
+ return 0;
+ }
+ ether_addr_copy(eth_hdr(skb)->h_dest, dev->dev_addr);
+ skb->pkt_type = PACKET_HOST;
+ } else {
+ rt = bridge_parent_rtable(nf_bridge->physindev);
+ if (!rt) {
+ kfree_skb(skb);
+ return 0;
+ }
+ skb_dst_set_noref(skb, &rt->dst);
+ }
+
+ skb->dev = nf_bridge->physindev;
+ nf_bridge_update_protocol(skb);
+ nf_bridge_push_encap_header(skb);
+ NF_HOOK_THRESH(NFPROTO_BRIDGE, NF_BR_PRE_ROUTING, sk, skb,
+ skb->dev, NULL,
+ br_handle_frame_finish, 1);
+
+ return 0;
+}
+
+/* Replicate the checks that IPv6 does on packet reception and pass the packet
+ * to ip6tables.
+ */
+unsigned int br_nf_pre_routing_ipv6(const struct nf_hook_ops *ops,
+ struct sk_buff *skb,
+ const struct nf_hook_state *state)
+{
+ struct nf_bridge_info *nf_bridge;
+
+ if (br_validate_ipv6(skb))
+ return NF_DROP;
+
+ nf_bridge_put(skb->nf_bridge);
+ if (!nf_bridge_alloc(skb))
+ return NF_DROP;
+ if (!setup_pre_routing(skb))
+ return NF_DROP;
+
+ nf_bridge = nf_bridge_info_get(skb);
+ nf_bridge->ipv6_daddr = ipv6_hdr(skb)->daddr;
+
+ skb->protocol = htons(ETH_P_IPV6);
+ NF_HOOK(NFPROTO_IPV6, NF_INET_PRE_ROUTING, state->sk, skb,
+ skb->dev, NULL,
+ br_nf_pre_routing_finish_ipv6);
+
+ return NF_STOLEN;
+}
projects / linux-beck.git / commitdiff