1 /* 2 * Header for use in defining a given L4 protocol for connection tracking. 3 * 4 * 16 Dec 2003: Yasuyuki Kozakai @USAGI <yasuyuki.kozakai@toshiba.co.jp> 5 * - generalized L3 protocol dependent part. 6 * 7 * Derived from include/linux/netfiter_ipv4/ip_conntrack_protcol.h 8 */ 9 10 #ifndef _NF_CONNTRACK_L4PROTO_H 11 #define _NF_CONNTRACK_L4PROTO_H 12 #include <linux/netlink.h> 13 #include <net/netlink.h> 14 #include <net/netfilter/nf_conntrack.h> 15 #include <net/netns/generic.h> 16 17 struct seq_file; 18 19 struct nf_conntrack_l4proto { 20 /* L3 Protocol number. */ 21 u_int16_t l3proto; 22 23 /* L4 Protocol number. */ 24 u_int8_t l4proto; 25 26 /* Try to fill in the third arg: dataoff is offset past network protocol 27 hdr. Return true if possible. */ 28 bool (*pkt_to_tuple)(const struct sk_buff *skb, unsigned int dataoff, 29 struct net *net, struct nf_conntrack_tuple *tuple); 30 31 /* Invert the per-proto part of the tuple: ie. turn xmit into reply. 32 * Some packets can't be inverted: return 0 in that case. 33 */ 34 bool (*invert_tuple)(struct nf_conntrack_tuple *inverse, 35 const struct nf_conntrack_tuple *orig); 36 37 /* Returns verdict for packet, or -1 for invalid. */ 38 int (*packet)(struct nf_conn *ct, 39 const struct sk_buff *skb, 40 unsigned int dataoff, 41 enum ip_conntrack_info ctinfo, 42 u_int8_t pf, 43 unsigned int hooknum, 44 unsigned int *timeouts); 45 46 /* Called when a new connection for this protocol found; 47 * returns TRUE if it's OK. If so, packet() called next. */ 48 bool (*new)(struct nf_conn *ct, const struct sk_buff *skb, 49 unsigned int dataoff, unsigned int *timeouts); 50 51 /* Called when a conntrack entry is destroyed */ 52 void (*destroy)(struct nf_conn *ct); 53 54 int (*error)(struct net *net, struct nf_conn *tmpl, struct sk_buff *skb, 55 unsigned int dataoff, enum ip_conntrack_info *ctinfo, 56 u_int8_t pf, unsigned int hooknum); 57 58 /* Print out the per-protocol part of the tuple. Return like seq_* */ 59 void (*print_tuple)(struct seq_file *s, 60 const struct nf_conntrack_tuple *); 61 62 /* Print out the private part of the conntrack. */ 63 void (*print_conntrack)(struct seq_file *s, struct nf_conn *); 64 65 /* Return the array of timeouts for this protocol. */ 66 unsigned int *(*get_timeouts)(struct net *net); 67 68 /* convert protoinfo to nfnetink attributes */ 69 int (*to_nlattr)(struct sk_buff *skb, struct nlattr *nla, 70 struct nf_conn *ct); 71 /* Calculate protoinfo nlattr size */ 72 int (*nlattr_size)(void); 73 74 /* convert nfnetlink attributes to protoinfo */ 75 int (*from_nlattr)(struct nlattr *tb[], struct nf_conn *ct); 76 77 int (*tuple_to_nlattr)(struct sk_buff *skb, 78 const struct nf_conntrack_tuple *t); 79 /* Calculate tuple nlattr size */ 80 int (*nlattr_tuple_size)(void); 81 int (*nlattr_to_tuple)(struct nlattr *tb[], 82 struct nf_conntrack_tuple *t); 83 const struct nla_policy *nla_policy; 84 85 size_t nla_size; 86 87 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT) 88 struct { 89 size_t obj_size; 90 int (*nlattr_to_obj)(struct nlattr *tb[], 91 struct net *net, void *data); 92 int (*obj_to_nlattr)(struct sk_buff *skb, const void *data); 93 94 unsigned int nlattr_max; 95 const struct nla_policy *nla_policy; 96 } ctnl_timeout; 97 #endif 98 int *net_id; 99 /* Init l4proto pernet data */ 100 int (*init_net)(struct net *net, u_int16_t proto); 101 102 /* Return the per-net protocol part. */ 103 struct nf_proto_net *(*get_net_proto)(struct net *net); 104 105 /* Protocol name */ 106 const char *name; 107 108 /* Module (if any) which this is connected to. */ 109 struct module *me; 110 }; 111 112 /* Existing built-in generic protocol */ 113 extern struct nf_conntrack_l4proto nf_conntrack_l4proto_generic; 114 115 #define MAX_NF_CT_PROTO 256 116 117 struct nf_conntrack_l4proto *__nf_ct_l4proto_find(u_int16_t l3proto, 118 u_int8_t l4proto); 119 120 struct nf_conntrack_l4proto *nf_ct_l4proto_find_get(u_int16_t l3proto, 121 u_int8_t l4proto); 122 void nf_ct_l4proto_put(struct nf_conntrack_l4proto *p); 123 124 /* Protocol pernet registration. */ 125 int nf_ct_l4proto_pernet_register(struct net *net, 126 struct nf_conntrack_l4proto *proto); 127 void nf_ct_l4proto_pernet_unregister(struct net *net, 128 struct nf_conntrack_l4proto *proto); 129 130 /* Protocol global registration. */ 131 int nf_ct_l4proto_register(struct nf_conntrack_l4proto *proto); 132 void nf_ct_l4proto_unregister(struct nf_conntrack_l4proto *proto); 133 134 static inline void nf_ct_kfree_compat_sysctl_table(struct nf_proto_net *pn) 135 { 136 #if defined(CONFIG_SYSCTL) && defined(CONFIG_NF_CONNTRACK_PROC_COMPAT) 137 kfree(pn->ctl_compat_table); 138 pn->ctl_compat_table = NULL; 139 #endif 140 } 141 142 /* Generic netlink helpers */ 143 int nf_ct_port_tuple_to_nlattr(struct sk_buff *skb, 144 const struct nf_conntrack_tuple *tuple); 145 int nf_ct_port_nlattr_to_tuple(struct nlattr *tb[], 146 struct nf_conntrack_tuple *t); 147 int nf_ct_port_nlattr_tuple_size(void); 148 extern const struct nla_policy nf_ct_port_nla_policy[]; 149 150 #ifdef CONFIG_SYSCTL 151 #define LOG_INVALID(net, proto) \ 152 ((net)->ct.sysctl_log_invalid == (proto) || \ 153 (net)->ct.sysctl_log_invalid == IPPROTO_RAW) 154 #else 155 static inline int LOG_INVALID(struct net *net, int proto) { return 0; } 156 #endif /* CONFIG_SYSCTL */ 157 158 #endif /*_NF_CONNTRACK_PROTOCOL_H*/ 159