| #ifndef __LINUX_NETFILTER_H |
| #define __LINUX_NETFILTER_H |
| |
| #include <linux/init.h> |
| #include <linux/skbuff.h> |
| #include <linux/net.h> |
| #include <linux/if.h> |
| #include <linux/in.h> |
| #include <linux/in6.h> |
| #include <linux/wait.h> |
| #include <linux/list.h> |
| #include <uapi/linux/netfilter.h> |
| #ifdef CONFIG_NETFILTER |
| static inline int NF_DROP_GETERR(int verdict) |
| { |
| return -(verdict >> NF_VERDICT_QBITS); |
| } |
| |
| 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]; |
| } |
| |
| static inline void nf_inet_addr_mask(const union nf_inet_addr *a1, |
| union nf_inet_addr *result, |
| const union nf_inet_addr *mask) |
| { |
| result->all[0] = a1->all[0] & mask->all[0]; |
| result->all[1] = a1->all[1] & mask->all[1]; |
| result->all[2] = a1->all[2] & mask->all[2]; |
| result->all[3] = a1->all[3] & mask->all[3]; |
| } |
| |
| int 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; |
| u_int8_t pf; |
| unsigned int hooknum; |
| /* Hooks are ordered in ascending priority. */ |
| int priority; |
| }; |
| |
| struct nf_sockopt_ops { |
| struct list_head list; |
| |
| u_int8_t 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); |
| #ifdef CONFIG_COMPAT |
| int (*compat_set)(struct sock *sk, int optval, |
| void __user *user, unsigned int len); |
| #endif |
| int get_optmin; |
| int get_optmax; |
| int (*get)(struct sock *sk, int optval, void __user *user, int *len); |
| #ifdef CONFIG_COMPAT |
| int (*compat_get)(struct sock *sk, int optval, |
| void __user *user, int *len); |
| #endif |
| /* 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); |
| |
| extern struct list_head nf_hooks[NFPROTO_NUMPROTO][NF_MAX_HOOKS]; |
| |
| #if defined(CONFIG_JUMP_LABEL) |
| #include <linux/static_key.h> |
| extern struct static_key nf_hooks_needed[NFPROTO_NUMPROTO][NF_MAX_HOOKS]; |
| static inline bool nf_hooks_active(u_int8_t pf, unsigned int hook) |
| { |
| if (__builtin_constant_p(pf) && |
| __builtin_constant_p(hook)) |
| return static_key_false(&nf_hooks_needed[pf][hook]); |
| |
| return !list_empty(&nf_hooks[pf][hook]); |
| } |
| #else |
| static inline bool nf_hooks_active(u_int8_t pf, unsigned int hook) |
| { |
| return !list_empty(&nf_hooks[pf][hook]); |
| } |
| #endif |
| |
| int nf_hook_slow(u_int8_t 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(u_int8_t pf, unsigned int hook, |
| struct sk_buff *skb, |
| struct net_device *indev, |
| struct net_device *outdev, |
| int (*okfn)(struct sk_buff *), int thresh) |
| { |
| if (nf_hooks_active(pf, hook)) |
| return nf_hook_slow(pf, hook, skb, indev, outdev, okfn, thresh); |
| return 1; |
| } |
| |
| static inline int nf_hook(u_int8_t 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); |
| } |
| |
| /* 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 :) |
| */ |
| |
| static inline int |
| NF_HOOK_THRESH(uint8_t pf, unsigned int hook, struct sk_buff *skb, |
| struct net_device *in, struct net_device *out, |
| int (*okfn)(struct sk_buff *), int thresh) |
| { |
| int ret = nf_hook_thresh(pf, hook, skb, in, out, okfn, thresh); |
| if (ret == 1) |
| ret = okfn(skb); |
| return ret; |
| } |
| |
| static inline int |
| NF_HOOK_COND(uint8_t pf, unsigned int hook, struct sk_buff *skb, |
| struct net_device *in, struct net_device *out, |
| int (*okfn)(struct sk_buff *), bool cond) |
| { |
| int ret; |
| |
| if (!cond || |
| ((ret = nf_hook_thresh(pf, hook, skb, in, out, okfn, INT_MIN)) == 1)) |
| ret = okfn(skb); |
| return ret; |
| } |
| |
| static inline int |
| NF_HOOK(uint8_t pf, unsigned int hook, struct sk_buff *skb, |
| struct net_device *in, struct net_device *out, |
| int (*okfn)(struct sk_buff *)) |
| { |
| return NF_HOOK_THRESH(pf, hook, skb, in, out, okfn, INT_MIN); |
| } |
| |
| /* Call setsockopt() */ |
| int nf_setsockopt(struct sock *sk, u_int8_t pf, int optval, char __user *opt, |
| unsigned int len); |
| int nf_getsockopt(struct sock *sk, u_int8_t pf, int optval, char __user *opt, |
| int *len); |
| #ifdef CONFIG_COMPAT |
| int compat_nf_setsockopt(struct sock *sk, u_int8_t pf, int optval, |
| char __user *opt, unsigned int len); |
| int compat_nf_getsockopt(struct sock *sk, u_int8_t pf, int optval, |
| char __user *opt, int *len); |
| #endif |
| |
| /* 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. */ |
| 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 net *net, struct dst_entry **dst, |
| struct flowi *fl, bool strict); |
| 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 __rcu *nf_afinfo[NFPROTO_NUMPROTO]; |
| 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; |
| } |
| |
| int nf_register_afinfo(const struct nf_afinfo *afinfo); |
| void nf_unregister_afinfo(const struct nf_afinfo *afinfo); |
| |
| #include <net/flow.h> |
| extern void (*nf_nat_decode_session_hook)(struct sk_buff *, struct flowi *); |
| |
| static inline void |
| nf_nat_decode_session(struct sk_buff *skb, struct flowi *fl, u_int8_t family) |
| { |
| #ifdef CONFIG_NF_NAT_NEEDED |
| void (*decodefn)(struct sk_buff *, struct flowi *); |
| |
| rcu_read_lock(); |
| decodefn = rcu_dereference(nf_nat_decode_session_hook); |
| if (decodefn) |
| decodefn(skb, fl); |
| rcu_read_unlock(); |
| #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(u_int8_t pf, unsigned int hook, |
| struct sk_buff *skb, |
| struct net_device *indev, |
| struct net_device *outdev, |
| int (*okfn)(struct sk_buff *), int thresh) |
| { |
| return okfn(skb); |
| } |
| static inline int nf_hook(u_int8_t 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, u_int8_t family) |
| { |
| } |
| #endif /*CONFIG_NETFILTER*/ |
| |
| #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) |
| extern void (*ip_ct_attach)(struct sk_buff *, const struct sk_buff *) __rcu; |
| void nf_ct_attach(struct sk_buff *, const struct sk_buff *); |
| extern void (*nf_ct_destroy)(struct nf_conntrack *) __rcu; |
| |
| struct nf_conn; |
| enum ip_conntrack_info; |
| struct nlattr; |
| |
| struct nfq_ct_hook { |
| size_t (*build_size)(const struct nf_conn *ct); |
| int (*build)(struct sk_buff *skb, struct nf_conn *ct); |
| int (*parse)(const struct nlattr *attr, struct nf_conn *ct); |
| int (*attach_expect)(const struct nlattr *attr, struct nf_conn *ct, |
| u32 portid, u32 report); |
| void (*seq_adjust)(struct sk_buff *skb, struct nf_conn *ct, |
| enum ip_conntrack_info ctinfo, s32 off); |
| }; |
| extern struct nfq_ct_hook __rcu *nfq_ct_hook; |
| #else |
| static inline void nf_ct_attach(struct sk_buff *new, struct sk_buff *skb) {} |
| #endif |
| |
| #endif /*__LINUX_NETFILTER_H*/ |