netfilter: bridge: split ipv6 code into separated file
Resolve compilation breakage when CONFIG_IPV6 is not set by moving the IPv6
code into a separated br_netfilter_ipv6.c file.
Fixes: efb6de9b4b
("netfilter: bridge: forward IPv6 fragmented packets")
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This commit is contained in:
parent
c4e70a87d9
commit
230ac490f7
4 changed files with 315 additions and 239 deletions
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@ -1,6 +1,66 @@
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#ifndef _BR_NETFILTER_H_
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#ifndef _BR_NETFILTER_H_
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#define _BR_NETFILTER_H_
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#define _BR_NETFILTER_H_
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#include "../../../net/bridge/br_private.h"
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static inline struct nf_bridge_info *nf_bridge_alloc(struct sk_buff *skb)
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{
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skb->nf_bridge = kzalloc(sizeof(struct nf_bridge_info), GFP_ATOMIC);
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if (likely(skb->nf_bridge))
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atomic_set(&(skb->nf_bridge->use), 1);
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return skb->nf_bridge;
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}
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void nf_bridge_update_protocol(struct sk_buff *skb);
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static inline struct nf_bridge_info *
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nf_bridge_info_get(const struct sk_buff *skb)
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{
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return skb->nf_bridge;
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}
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unsigned int nf_bridge_encap_header_len(const struct sk_buff *skb);
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static inline void nf_bridge_push_encap_header(struct sk_buff *skb)
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{
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unsigned int len = nf_bridge_encap_header_len(skb);
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skb_push(skb, len);
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skb->network_header -= len;
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}
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int br_nf_pre_routing_finish_bridge(struct sock *sk, struct sk_buff *skb);
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static inline struct rtable *bridge_parent_rtable(const struct net_device *dev)
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{
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struct net_bridge_port *port;
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port = br_port_get_rcu(dev);
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return port ? &port->br->fake_rtable : NULL;
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}
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struct net_device *setup_pre_routing(struct sk_buff *skb);
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void br_netfilter_enable(void);
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void br_netfilter_enable(void);
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#if IS_ENABLED(CONFIG_IPV6)
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int br_validate_ipv6(struct sk_buff *skb);
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unsigned int br_nf_pre_routing_ipv6(const struct nf_hook_ops *ops,
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struct sk_buff *skb,
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const struct nf_hook_state *state);
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#else
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static inline int br_validate_ipv6(struct sk_buff *skb)
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{
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return -1;
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}
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static inline unsigned int
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br_nf_pre_routing_ipv6(const struct nf_hook_ops *ops, struct sk_buff *skb,
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const struct nf_hook_state *state)
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{
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return NF_DROP;
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}
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#endif
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#endif /* _BR_NETFILTER_H_ */
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#endif /* _BR_NETFILTER_H_ */
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@ -13,6 +13,7 @@ bridge-$(CONFIG_SYSFS) += br_sysfs_if.o br_sysfs_br.o
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bridge-$(subst m,y,$(CONFIG_BRIDGE_NETFILTER)) += br_nf_core.o
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bridge-$(subst m,y,$(CONFIG_BRIDGE_NETFILTER)) += br_nf_core.o
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br_netfilter-y := br_netfilter_hooks.o
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br_netfilter-y := br_netfilter_hooks.o
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br_netfilter-$(subst m,y,$(CONFIG_IPV6)) += br_netfilter_ipv6.o
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obj-$(CONFIG_BRIDGE_NETFILTER) += br_netfilter.o
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obj-$(CONFIG_BRIDGE_NETFILTER) += br_netfilter.o
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bridge-$(CONFIG_BRIDGE_IGMP_SNOOPING) += br_multicast.o br_mdb.o
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bridge-$(CONFIG_BRIDGE_IGMP_SNOOPING) += br_multicast.o br_mdb.o
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@ -123,11 +123,6 @@ struct brnf_frag_data {
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static DEFINE_PER_CPU(struct brnf_frag_data, brnf_frag_data_storage);
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static DEFINE_PER_CPU(struct brnf_frag_data, brnf_frag_data_storage);
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#endif
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#endif
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static struct nf_bridge_info *nf_bridge_info_get(const struct sk_buff *skb)
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{
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return skb->nf_bridge;
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}
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static void nf_bridge_info_free(struct sk_buff *skb)
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static void nf_bridge_info_free(struct sk_buff *skb)
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{
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{
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if (skb->nf_bridge) {
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if (skb->nf_bridge) {
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@ -136,14 +131,6 @@ static void nf_bridge_info_free(struct sk_buff *skb)
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}
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}
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}
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}
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static inline struct rtable *bridge_parent_rtable(const struct net_device *dev)
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{
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struct net_bridge_port *port;
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port = br_port_get_rcu(dev);
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return port ? &port->br->fake_rtable : NULL;
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}
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static inline struct net_device *bridge_parent(const struct net_device *dev)
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static inline struct net_device *bridge_parent(const struct net_device *dev)
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{
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{
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struct net_bridge_port *port;
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struct net_bridge_port *port;
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@ -152,15 +139,6 @@ static inline struct net_device *bridge_parent(const struct net_device *dev)
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return port ? port->br->dev : NULL;
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return port ? port->br->dev : NULL;
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}
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}
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static inline struct nf_bridge_info *nf_bridge_alloc(struct sk_buff *skb)
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{
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skb->nf_bridge = kzalloc(sizeof(struct nf_bridge_info), GFP_ATOMIC);
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if (likely(skb->nf_bridge))
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atomic_set(&(skb->nf_bridge->use), 1);
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return skb->nf_bridge;
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}
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static inline struct nf_bridge_info *nf_bridge_unshare(struct sk_buff *skb)
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static inline struct nf_bridge_info *nf_bridge_unshare(struct sk_buff *skb)
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{
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{
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struct nf_bridge_info *nf_bridge = skb->nf_bridge;
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struct nf_bridge_info *nf_bridge = skb->nf_bridge;
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@ -178,7 +156,7 @@ static inline struct nf_bridge_info *nf_bridge_unshare(struct sk_buff *skb)
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return nf_bridge;
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return nf_bridge;
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}
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}
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static unsigned int nf_bridge_encap_header_len(const struct sk_buff *skb)
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unsigned int nf_bridge_encap_header_len(const struct sk_buff *skb)
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{
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{
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switch (skb->protocol) {
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switch (skb->protocol) {
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case __cpu_to_be16(ETH_P_8021Q):
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case __cpu_to_be16(ETH_P_8021Q):
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@ -190,14 +168,6 @@ static unsigned int nf_bridge_encap_header_len(const struct sk_buff *skb)
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}
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}
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}
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}
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static inline void nf_bridge_push_encap_header(struct sk_buff *skb)
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{
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unsigned int len = nf_bridge_encap_header_len(skb);
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skb_push(skb, len);
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skb->network_header -= len;
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}
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static inline void nf_bridge_pull_encap_header(struct sk_buff *skb)
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static inline void nf_bridge_pull_encap_header(struct sk_buff *skb)
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{
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{
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unsigned int len = nf_bridge_encap_header_len(skb);
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unsigned int len = nf_bridge_encap_header_len(skb);
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@ -267,112 +237,7 @@ drop:
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return -1;
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return -1;
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}
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}
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/* We only check the length. A bridge shouldn't do any hop-by-hop stuff
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void nf_bridge_update_protocol(struct sk_buff *skb)
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* anyway
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*/
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static int check_hbh_len(struct sk_buff *skb)
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{
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unsigned char *raw = (u8 *)(ipv6_hdr(skb) + 1);
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u32 pkt_len;
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const unsigned char *nh = skb_network_header(skb);
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int off = raw - nh;
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int len = (raw[1] + 1) << 3;
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if ((raw + len) - skb->data > skb_headlen(skb))
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goto bad;
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off += 2;
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len -= 2;
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while (len > 0) {
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int optlen = nh[off + 1] + 2;
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switch (nh[off]) {
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case IPV6_TLV_PAD1:
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optlen = 1;
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break;
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case IPV6_TLV_PADN:
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break;
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case IPV6_TLV_JUMBO:
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if (nh[off + 1] != 4 || (off & 3) != 2)
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goto bad;
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pkt_len = ntohl(*(__be32 *)(nh + off + 2));
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if (pkt_len <= IPV6_MAXPLEN ||
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ipv6_hdr(skb)->payload_len)
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goto bad;
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if (pkt_len > skb->len - sizeof(struct ipv6hdr))
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goto bad;
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if (pskb_trim_rcsum(skb,
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pkt_len + sizeof(struct ipv6hdr)))
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goto bad;
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nh = skb_network_header(skb);
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break;
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default:
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if (optlen > len)
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goto bad;
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break;
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}
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off += optlen;
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len -= optlen;
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}
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if (len == 0)
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return 0;
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bad:
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return -1;
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}
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/* Equivalent to br_validate_ipv4 for IPv6 */
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static int br_validate_ipv6(struct sk_buff *skb)
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{
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const struct ipv6hdr *hdr;
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struct net_device *dev = skb->dev;
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struct inet6_dev *idev = in6_dev_get(skb->dev);
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u32 pkt_len;
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u8 ip6h_len = sizeof(struct ipv6hdr);
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if (!pskb_may_pull(skb, ip6h_len))
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goto inhdr_error;
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if (skb->len < ip6h_len)
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goto drop;
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hdr = ipv6_hdr(skb);
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if (hdr->version != 6)
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goto inhdr_error;
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pkt_len = ntohs(hdr->payload_len);
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if (pkt_len || hdr->nexthdr != NEXTHDR_HOP) {
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if (pkt_len + ip6h_len > skb->len) {
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IP6_INC_STATS_BH(dev_net(dev), idev,
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IPSTATS_MIB_INTRUNCATEDPKTS);
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goto drop;
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}
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if (pskb_trim_rcsum(skb, pkt_len + ip6h_len)) {
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IP6_INC_STATS_BH(dev_net(dev), idev,
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IPSTATS_MIB_INDISCARDS);
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goto drop;
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}
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}
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if (hdr->nexthdr == NEXTHDR_HOP && check_hbh_len(skb))
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goto drop;
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memset(IP6CB(skb), 0, sizeof(struct inet6_skb_parm));
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/* No IP options in IPv6 header; however it should be
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* checked if some next headers need special treatment
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*/
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return 0;
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inhdr_error:
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IP6_INC_STATS_BH(dev_net(dev), idev, IPSTATS_MIB_INHDRERRORS);
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drop:
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return -1;
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}
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static void nf_bridge_update_protocol(struct sk_buff *skb)
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{
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{
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switch (skb->nf_bridge->orig_proto) {
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switch (skb->nf_bridge->orig_proto) {
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case BRNF_PROTO_8021Q:
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case BRNF_PROTO_8021Q:
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@ -391,7 +256,7 @@ static void nf_bridge_update_protocol(struct sk_buff *skb)
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* don't, we use the neighbour framework to find out. In both cases, we make
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* don't, we use the neighbour framework to find out. In both cases, we make
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* sure that br_handle_frame_finish() is called afterwards.
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* sure that br_handle_frame_finish() is called afterwards.
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*/
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*/
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static int br_nf_pre_routing_finish_bridge(struct sock *sk, struct sk_buff *skb)
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int br_nf_pre_routing_finish_bridge(struct sock *sk, struct sk_buff *skb)
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{
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{
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struct neighbour *neigh;
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struct neighbour *neigh;
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struct dst_entry *dst;
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struct dst_entry *dst;
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@ -431,77 +296,11 @@ free_skb:
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return 0;
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return 0;
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}
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}
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static bool daddr_was_changed(const struct sk_buff *skb,
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static inline bool
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const struct nf_bridge_info *nf_bridge)
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br_nf_ipv4_daddr_was_changed(const struct sk_buff *skb,
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const struct nf_bridge_info *nf_bridge)
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{
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{
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switch (skb->protocol) {
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return ip_hdr(skb)->daddr != nf_bridge->ipv4_daddr;
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case htons(ETH_P_IP):
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return ip_hdr(skb)->daddr != nf_bridge->ipv4_daddr;
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case htons(ETH_P_IPV6):
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return memcmp(&nf_bridge->ipv6_daddr, &ipv6_hdr(skb)->daddr,
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sizeof(ipv6_hdr(skb)->daddr)) != 0;
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default:
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return false;
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}
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}
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/* PF_BRIDGE/PRE_ROUTING: Undo the changes made for ip6tables
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* PREROUTING and continue the bridge PRE_ROUTING hook. See comment
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* for br_nf_pre_routing_finish(), same logic is used here but
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* equivalent IPv6 function ip6_route_input() called indirectly.
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*/
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static int br_nf_pre_routing_finish_ipv6(struct sock *sk, struct sk_buff *skb)
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{
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struct nf_bridge_info *nf_bridge = nf_bridge_info_get(skb);
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struct rtable *rt;
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struct net_device *dev = skb->dev;
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const struct nf_ipv6_ops *v6ops = nf_get_ipv6_ops();
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nf_bridge->frag_max_size = IP6CB(skb)->frag_max_size;
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if (nf_bridge->pkt_otherhost) {
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skb->pkt_type = PACKET_OTHERHOST;
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nf_bridge->pkt_otherhost = false;
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}
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nf_bridge->mask &= ~BRNF_NF_BRIDGE_PREROUTING;
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if (daddr_was_changed(skb, nf_bridge)) {
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skb_dst_drop(skb);
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v6ops->route_input(skb);
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if (skb_dst(skb)->error) {
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kfree_skb(skb);
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return 0;
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}
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if (skb_dst(skb)->dev == dev) {
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skb->dev = nf_bridge->physindev;
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nf_bridge_update_protocol(skb);
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nf_bridge_push_encap_header(skb);
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NF_HOOK_THRESH(NFPROTO_BRIDGE, NF_BR_PRE_ROUTING,
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sk, skb, skb->dev, NULL,
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br_nf_pre_routing_finish_bridge,
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1);
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return 0;
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}
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ether_addr_copy(eth_hdr(skb)->h_dest, dev->dev_addr);
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skb->pkt_type = PACKET_HOST;
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} else {
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rt = bridge_parent_rtable(nf_bridge->physindev);
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if (!rt) {
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kfree_skb(skb);
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return 0;
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}
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skb_dst_set_noref(skb, &rt->dst);
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}
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skb->dev = nf_bridge->physindev;
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nf_bridge_update_protocol(skb);
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nf_bridge_push_encap_header(skb);
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NF_HOOK_THRESH(NFPROTO_BRIDGE, NF_BR_PRE_ROUTING, sk, skb,
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skb->dev, NULL,
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br_handle_frame_finish, 1);
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return 0;
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}
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}
|
||||||
|
|
||||||
/* This requires some explaining. If DNAT has taken place,
|
/* This requires some explaining. If DNAT has taken place,
|
||||||
|
@ -558,7 +357,7 @@ static int br_nf_pre_routing_finish(struct sock *sk, struct sk_buff *skb)
|
||||||
nf_bridge->pkt_otherhost = false;
|
nf_bridge->pkt_otherhost = false;
|
||||||
}
|
}
|
||||||
nf_bridge->mask &= ~BRNF_NF_BRIDGE_PREROUTING;
|
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))) {
|
if ((err = ip_route_input(skb, iph->daddr, iph->saddr, iph->tos, dev))) {
|
||||||
struct in_device *in_dev = __in_dev_get_rcu(dev);
|
struct in_device *in_dev = __in_dev_get_rcu(dev);
|
||||||
|
|
||||||
|
@ -636,7 +435,7 @@ static struct net_device *brnf_get_logical_dev(struct sk_buff *skb, const struct
|
||||||
}
|
}
|
||||||
|
|
||||||
/* Some common code for IPv4/IPv6 */
|
/* 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);
|
struct nf_bridge_info *nf_bridge = nf_bridge_info_get(skb);
|
||||||
|
|
||||||
|
@ -659,35 +458,6 @@ static struct net_device *setup_pre_routing(struct sk_buff *skb)
|
||||||
return skb->dev;
|
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.
|
/* Direct IPv6 traffic to br_nf_pre_routing_ipv6.
|
||||||
* Replicate the checks that IPv4 does on packet reception.
|
* Replicate the checks that IPv4 does on packet reception.
|
||||||
* Set skb->dev to the bridge device (i.e. parent of the
|
* Set skb->dev to the bridge device (i.e. parent of the
|
||||||
|
|
245
net/bridge/br_netfilter_ipv6.c
Normal file
245
net/bridge/br_netfilter_ipv6.c
Normal file
|
@ -0,0 +1,245 @@
|
||||||
|
/*
|
||||||
|
* 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;
|
||||||
|
}
|
Loading…
Add table
Reference in a new issue