|  | #ifndef __LINUX_NETFILTER_H | 
|  | #define __LINUX_NETFILTER_H | 
|  |  | 
|  | #ifdef __KERNEL__ | 
|  | #include <linux/init.h> | 
|  | #include <linux/types.h> | 
|  | #include <linux/skbuff.h> | 
|  | #include <linux/net.h> | 
|  | #include <linux/netdevice.h> | 
|  | #include <linux/if.h> | 
|  | #include <linux/in.h> | 
|  | #include <linux/in6.h> | 
|  | #include <linux/wait.h> | 
|  | #include <linux/list.h> | 
|  | #include <net/net_namespace.h> | 
|  | #endif | 
|  | #include <linux/compiler.h> | 
|  |  | 
|  | /* Responses from hook functions. */ | 
|  | #define NF_DROP 0 | 
|  | #define NF_ACCEPT 1 | 
|  | #define NF_STOLEN 2 | 
|  | #define NF_QUEUE 3 | 
|  | #define NF_REPEAT 4 | 
|  | #define NF_STOP 5 | 
|  | #define NF_MAX_VERDICT NF_STOP | 
|  |  | 
|  | /* we overload the higher bits for encoding auxiliary data such as the queue | 
|  | * number. Not nice, but better than additional function arguments. */ | 
|  | #define NF_VERDICT_MASK 0x0000ffff | 
|  | #define NF_VERDICT_BITS 16 | 
|  |  | 
|  | #define NF_VERDICT_QMASK 0xffff0000 | 
|  | #define NF_VERDICT_QBITS 16 | 
|  |  | 
|  | #define NF_QUEUE_NR(x) ((((x) << NF_VERDICT_BITS) & NF_VERDICT_QMASK) | NF_QUEUE) | 
|  |  | 
|  | /* only for userspace compatibility */ | 
|  | #ifndef __KERNEL__ | 
|  | /* Generic cache responses from hook functions. | 
|  | <= 0x2000 is used for protocol-flags. */ | 
|  | #define NFC_UNKNOWN 0x4000 | 
|  | #define NFC_ALTERED 0x8000 | 
|  | #endif | 
|  |  | 
|  | enum nf_inet_hooks { | 
|  | NF_INET_PRE_ROUTING, | 
|  | NF_INET_LOCAL_IN, | 
|  | NF_INET_FORWARD, | 
|  | NF_INET_LOCAL_OUT, | 
|  | NF_INET_POST_ROUTING, | 
|  | NF_INET_NUMHOOKS | 
|  | }; | 
|  |  | 
|  | union nf_inet_addr { | 
|  | __u32		all[4]; | 
|  | __be32		ip; | 
|  | __be32		ip6[4]; | 
|  | struct in_addr	in; | 
|  | struct in6_addr	in6; | 
|  | }; | 
|  |  | 
|  | #ifdef __KERNEL__ | 
|  | #ifdef CONFIG_NETFILTER | 
|  |  | 
|  | static inline int nf_inet_addr_cmp(const union nf_inet_addr *a1, | 
|  | const union nf_inet_addr *a2) | 
|  | { | 
|  | return a1->all[0] == a2->all[0] && | 
|  | a1->all[1] == a2->all[1] && | 
|  | a1->all[2] == a2->all[2] && | 
|  | a1->all[3] == a2->all[3]; | 
|  | } | 
|  |  | 
|  | extern void netfilter_init(void); | 
|  |  | 
|  | /* Largest hook number + 1 */ | 
|  | #define NF_MAX_HOOKS 8 | 
|  |  | 
|  | struct sk_buff; | 
|  |  | 
|  | typedef unsigned int nf_hookfn(unsigned int hooknum, | 
|  | struct sk_buff *skb, | 
|  | const struct net_device *in, | 
|  | const struct net_device *out, | 
|  | int (*okfn)(struct sk_buff *)); | 
|  |  | 
|  | struct nf_hook_ops | 
|  | { | 
|  | struct list_head list; | 
|  |  | 
|  | /* User fills in from here down. */ | 
|  | nf_hookfn *hook; | 
|  | struct module *owner; | 
|  | int pf; | 
|  | int hooknum; | 
|  | /* Hooks are ordered in ascending priority. */ | 
|  | int priority; | 
|  | }; | 
|  |  | 
|  | struct nf_sockopt_ops | 
|  | { | 
|  | struct list_head list; | 
|  |  | 
|  | int pf; | 
|  |  | 
|  | /* Non-inclusive ranges: use 0/0/NULL to never get called. */ | 
|  | int set_optmin; | 
|  | int set_optmax; | 
|  | int (*set)(struct sock *sk, int optval, void __user *user, unsigned int len); | 
|  | int (*compat_set)(struct sock *sk, int optval, | 
|  | void __user *user, unsigned int len); | 
|  |  | 
|  | int get_optmin; | 
|  | int get_optmax; | 
|  | int (*get)(struct sock *sk, int optval, void __user *user, int *len); | 
|  | int (*compat_get)(struct sock *sk, int optval, | 
|  | void __user *user, int *len); | 
|  |  | 
|  | /* Use the module struct to lock set/get code in place */ | 
|  | struct module *owner; | 
|  | }; | 
|  |  | 
|  | /* Function to register/unregister hook points. */ | 
|  | int nf_register_hook(struct nf_hook_ops *reg); | 
|  | void nf_unregister_hook(struct nf_hook_ops *reg); | 
|  | int nf_register_hooks(struct nf_hook_ops *reg, unsigned int n); | 
|  | void nf_unregister_hooks(struct nf_hook_ops *reg, unsigned int n); | 
|  |  | 
|  | /* Functions to register get/setsockopt ranges (non-inclusive).  You | 
|  | need to check permissions yourself! */ | 
|  | int nf_register_sockopt(struct nf_sockopt_ops *reg); | 
|  | void nf_unregister_sockopt(struct nf_sockopt_ops *reg); | 
|  |  | 
|  | #ifdef CONFIG_SYSCTL | 
|  | /* Sysctl registration */ | 
|  | extern struct ctl_path nf_net_netfilter_sysctl_path[]; | 
|  | extern struct ctl_path nf_net_ipv4_netfilter_sysctl_path[]; | 
|  | #endif /* CONFIG_SYSCTL */ | 
|  |  | 
|  | extern struct list_head nf_hooks[NPROTO][NF_MAX_HOOKS]; | 
|  |  | 
|  | int nf_hook_slow(int pf, unsigned int hook, struct sk_buff *skb, | 
|  | struct net_device *indev, struct net_device *outdev, | 
|  | int (*okfn)(struct sk_buff *), int thresh); | 
|  |  | 
|  | /** | 
|  | *	nf_hook_thresh - call a netfilter hook | 
|  | * | 
|  | *	Returns 1 if the hook has allowed the packet to pass.  The function | 
|  | *	okfn must be invoked by the caller in this case.  Any other return | 
|  | *	value indicates the packet has been consumed by the hook. | 
|  | */ | 
|  | static inline int nf_hook_thresh(int pf, unsigned int hook, | 
|  | struct sk_buff *skb, | 
|  | struct net_device *indev, | 
|  | struct net_device *outdev, | 
|  | int (*okfn)(struct sk_buff *), int thresh, | 
|  | int cond) | 
|  | { | 
|  | if (!cond) | 
|  | return 1; | 
|  | #ifndef CONFIG_NETFILTER_DEBUG | 
|  | if (list_empty(&nf_hooks[pf][hook])) | 
|  | return 1; | 
|  | #endif | 
|  | return nf_hook_slow(pf, hook, skb, indev, outdev, okfn, thresh); | 
|  | } | 
|  |  | 
|  | static inline int nf_hook(int pf, unsigned int hook, struct sk_buff *skb, | 
|  | struct net_device *indev, struct net_device *outdev, | 
|  | int (*okfn)(struct sk_buff *)) | 
|  | { | 
|  | return nf_hook_thresh(pf, hook, skb, indev, outdev, okfn, INT_MIN, 1); | 
|  | } | 
|  |  | 
|  | /* Activate hook; either okfn or kfree_skb called, unless a hook | 
|  | returns NF_STOLEN (in which case, it's up to the hook to deal with | 
|  | the consequences). | 
|  |  | 
|  | Returns -ERRNO if packet dropped.  Zero means queued, stolen or | 
|  | accepted. | 
|  | */ | 
|  |  | 
|  | /* RR: | 
|  | > I don't want nf_hook to return anything because people might forget | 
|  | > about async and trust the return value to mean "packet was ok". | 
|  |  | 
|  | AK: | 
|  | Just document it clearly, then you can expect some sense from kernel | 
|  | coders :) | 
|  | */ | 
|  |  | 
|  | /* This is gross, but inline doesn't cut it for avoiding the function | 
|  | call in fast path: gcc doesn't inline (needs value tracking?). --RR */ | 
|  |  | 
|  | /* HX: It's slightly less gross now. */ | 
|  |  | 
|  | #define NF_HOOK_THRESH(pf, hook, skb, indev, outdev, okfn, thresh)	       \ | 
|  | ({int __ret;								       \ | 
|  | if ((__ret=nf_hook_thresh(pf, hook, (skb), indev, outdev, okfn, thresh, 1)) == 1)\ | 
|  | __ret = (okfn)(skb);						       \ | 
|  | __ret;}) | 
|  |  | 
|  | #define NF_HOOK_COND(pf, hook, skb, indev, outdev, okfn, cond)		       \ | 
|  | ({int __ret;								       \ | 
|  | if ((__ret=nf_hook_thresh(pf, hook, (skb), indev, outdev, okfn, INT_MIN, cond)) == 1)\ | 
|  | __ret = (okfn)(skb);						       \ | 
|  | __ret;}) | 
|  |  | 
|  | #define NF_HOOK(pf, hook, skb, indev, outdev, okfn) \ | 
|  | NF_HOOK_THRESH(pf, hook, skb, indev, outdev, okfn, INT_MIN) | 
|  |  | 
|  | /* Call setsockopt() */ | 
|  | int nf_setsockopt(struct sock *sk, int pf, int optval, char __user *opt, | 
|  | int len); | 
|  | int nf_getsockopt(struct sock *sk, int pf, int optval, char __user *opt, | 
|  | int *len); | 
|  |  | 
|  | int compat_nf_setsockopt(struct sock *sk, int pf, int optval, | 
|  | char __user *opt, int len); | 
|  | int compat_nf_getsockopt(struct sock *sk, int pf, int optval, | 
|  | char __user *opt, int *len); | 
|  |  | 
|  | /* Call this before modifying an existing packet: ensures it is | 
|  | modifiable and linear to the point you care about (writable_len). | 
|  | Returns true or false. */ | 
|  | extern int skb_make_writable(struct sk_buff *skb, unsigned int writable_len); | 
|  |  | 
|  | struct flowi; | 
|  | struct nf_queue_entry; | 
|  |  | 
|  | struct nf_afinfo { | 
|  | unsigned short	family; | 
|  | __sum16		(*checksum)(struct sk_buff *skb, unsigned int hook, | 
|  | unsigned int dataoff, u_int8_t protocol); | 
|  | __sum16		(*checksum_partial)(struct sk_buff *skb, | 
|  | unsigned int hook, | 
|  | unsigned int dataoff, | 
|  | unsigned int len, | 
|  | u_int8_t protocol); | 
|  | int		(*route)(struct dst_entry **dst, struct flowi *fl); | 
|  | void		(*saveroute)(const struct sk_buff *skb, | 
|  | struct nf_queue_entry *entry); | 
|  | int		(*reroute)(struct sk_buff *skb, | 
|  | const struct nf_queue_entry *entry); | 
|  | int		route_key_size; | 
|  | }; | 
|  |  | 
|  | extern const struct nf_afinfo *nf_afinfo[NPROTO]; | 
|  | static inline const struct nf_afinfo *nf_get_afinfo(unsigned short family) | 
|  | { | 
|  | return rcu_dereference(nf_afinfo[family]); | 
|  | } | 
|  |  | 
|  | static inline __sum16 | 
|  | nf_checksum(struct sk_buff *skb, unsigned int hook, unsigned int dataoff, | 
|  | u_int8_t protocol, unsigned short family) | 
|  | { | 
|  | const struct nf_afinfo *afinfo; | 
|  | __sum16 csum = 0; | 
|  |  | 
|  | rcu_read_lock(); | 
|  | afinfo = nf_get_afinfo(family); | 
|  | if (afinfo) | 
|  | csum = afinfo->checksum(skb, hook, dataoff, protocol); | 
|  | rcu_read_unlock(); | 
|  | return csum; | 
|  | } | 
|  |  | 
|  | static inline __sum16 | 
|  | nf_checksum_partial(struct sk_buff *skb, unsigned int hook, | 
|  | unsigned int dataoff, unsigned int len, | 
|  | u_int8_t protocol, unsigned short family) | 
|  | { | 
|  | const struct nf_afinfo *afinfo; | 
|  | __sum16 csum = 0; | 
|  |  | 
|  | rcu_read_lock(); | 
|  | afinfo = nf_get_afinfo(family); | 
|  | if (afinfo) | 
|  | csum = afinfo->checksum_partial(skb, hook, dataoff, len, | 
|  | protocol); | 
|  | rcu_read_unlock(); | 
|  | return csum; | 
|  | } | 
|  |  | 
|  | extern int nf_register_afinfo(const struct nf_afinfo *afinfo); | 
|  | extern void nf_unregister_afinfo(const struct nf_afinfo *afinfo); | 
|  |  | 
|  | #include <net/flow.h> | 
|  | extern void (*ip_nat_decode_session)(struct sk_buff *, struct flowi *); | 
|  |  | 
|  | static inline void | 
|  | nf_nat_decode_session(struct sk_buff *skb, struct flowi *fl, int family) | 
|  | { | 
|  | #ifdef CONFIG_NF_NAT_NEEDED | 
|  | void (*decodefn)(struct sk_buff *, struct flowi *); | 
|  |  | 
|  | if (family == AF_INET) { | 
|  | rcu_read_lock(); | 
|  | decodefn = rcu_dereference(ip_nat_decode_session); | 
|  | if (decodefn) | 
|  | decodefn(skb, fl); | 
|  | rcu_read_unlock(); | 
|  | } | 
|  | #endif | 
|  | } | 
|  |  | 
|  | #ifdef CONFIG_PROC_FS | 
|  | #include <linux/proc_fs.h> | 
|  | extern struct proc_dir_entry *proc_net_netfilter; | 
|  | #endif | 
|  |  | 
|  | #else /* !CONFIG_NETFILTER */ | 
|  | #define NF_HOOK(pf, hook, skb, indev, outdev, okfn) (okfn)(skb) | 
|  | #define NF_HOOK_COND(pf, hook, skb, indev, outdev, okfn, cond) (okfn)(skb) | 
|  | static inline int nf_hook_thresh(int pf, unsigned int hook, | 
|  | struct sk_buff *skb, | 
|  | struct net_device *indev, | 
|  | struct net_device *outdev, | 
|  | int (*okfn)(struct sk_buff *), int thresh, | 
|  | int cond) | 
|  | { | 
|  | return okfn(skb); | 
|  | } | 
|  | static inline int nf_hook(int pf, unsigned int hook, struct sk_buff *skb, | 
|  | struct net_device *indev, struct net_device *outdev, | 
|  | int (*okfn)(struct sk_buff *)) | 
|  | { | 
|  | return 1; | 
|  | } | 
|  | struct flowi; | 
|  | static inline void | 
|  | nf_nat_decode_session(struct sk_buff *skb, struct flowi *fl, int family) {} | 
|  | #endif /*CONFIG_NETFILTER*/ | 
|  |  | 
|  | #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) | 
|  | extern void (*ip_ct_attach)(struct sk_buff *, struct sk_buff *); | 
|  | extern void nf_ct_attach(struct sk_buff *, struct sk_buff *); | 
|  | extern void (*nf_ct_destroy)(struct nf_conntrack *); | 
|  | #else | 
|  | static inline void nf_ct_attach(struct sk_buff *new, struct sk_buff *skb) {} | 
|  | #endif | 
|  |  | 
|  | static inline struct net *nf_pre_routing_net(const struct net_device *in, | 
|  | const struct net_device *out) | 
|  | { | 
|  | #ifdef CONFIG_NET_NS | 
|  | return in->nd_net; | 
|  | #else | 
|  | return &init_net; | 
|  | #endif | 
|  | } | 
|  |  | 
|  | static inline struct net *nf_local_in_net(const struct net_device *in, | 
|  | const struct net_device *out) | 
|  | { | 
|  | #ifdef CONFIG_NET_NS | 
|  | return in->nd_net; | 
|  | #else | 
|  | return &init_net; | 
|  | #endif | 
|  | } | 
|  |  | 
|  | static inline struct net *nf_forward_net(const struct net_device *in, | 
|  | const struct net_device *out) | 
|  | { | 
|  | #ifdef CONFIG_NET_NS | 
|  | BUG_ON(in->nd_net != out->nd_net); | 
|  | return in->nd_net; | 
|  | #else | 
|  | return &init_net; | 
|  | #endif | 
|  | } | 
|  |  | 
|  | static inline struct net *nf_local_out_net(const struct net_device *in, | 
|  | const struct net_device *out) | 
|  | { | 
|  | #ifdef CONFIG_NET_NS | 
|  | return out->nd_net; | 
|  | #else | 
|  | return &init_net; | 
|  | #endif | 
|  | } | 
|  |  | 
|  | static inline struct net *nf_post_routing_net(const struct net_device *in, | 
|  | const struct net_device *out) | 
|  | { | 
|  | #ifdef CONFIG_NET_NS | 
|  | return out->nd_net; | 
|  | #else | 
|  | return &init_net; | 
|  | #endif | 
|  | } | 
|  |  | 
|  | #endif /*__KERNEL__*/ | 
|  | #endif /*__LINUX_NETFILTER_H*/ |