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 /* Resolve clashes on insertion races. */ 27 bool allow_clash; 28 29 /* Try to fill in the third arg: dataoff is offset past network protocol 30 hdr. Return true if possible. */ 31 bool (*pkt_to_tuple)(const struct sk_buff *skb, unsigned int dataoff, 32 struct net *net, struct nf_conntrack_tuple *tuple); 33 34 /* Invert the per-proto part of the tuple: ie. turn xmit into reply. 35 * Some packets can't be inverted: return 0 in that case. 36 */ 37 bool (*invert_tuple)(struct nf_conntrack_tuple *inverse, 38 const struct nf_conntrack_tuple *orig); 39 40 /* Returns verdict for packet, or -1 for invalid. */ 41 int (*packet)(struct nf_conn *ct, 42 const struct sk_buff *skb, 43 unsigned int dataoff, 44 enum ip_conntrack_info ctinfo, 45 u_int8_t pf, 46 unsigned int hooknum, 47 unsigned int *timeouts); 48 49 /* Called when a new connection for this protocol found; 50 * returns TRUE if it's OK. If so, packet() called next. */ 51 bool (*new)(struct nf_conn *ct, const struct sk_buff *skb, 52 unsigned int dataoff, unsigned int *timeouts); 53 54 /* Called when a conntrack entry is destroyed */ 55 void (*destroy)(struct nf_conn *ct); 56 57 int (*error)(struct net *net, struct nf_conn *tmpl, struct sk_buff *skb, 58 unsigned int dataoff, enum ip_conntrack_info *ctinfo, 59 u_int8_t pf, unsigned int hooknum); 60 61 /* Print out the per-protocol part of the tuple. Return like seq_* */ 62 void (*print_tuple)(struct seq_file *s, 63 const struct nf_conntrack_tuple *); 64 65 /* Print out the private part of the conntrack. */ 66 void (*print_conntrack)(struct seq_file *s, struct nf_conn *); 67 68 /* Return the array of timeouts for this protocol. */ 69 unsigned int *(*get_timeouts)(struct net *net); 70 71 /* convert protoinfo to nfnetink attributes */ 72 int (*to_nlattr)(struct sk_buff *skb, struct nlattr *nla, 73 struct nf_conn *ct); 74 /* Calculate protoinfo nlattr size */ 75 int (*nlattr_size)(void); 76 77 /* convert nfnetlink attributes to protoinfo */ 78 int (*from_nlattr)(struct nlattr *tb[], struct nf_conn *ct); 79 80 int (*tuple_to_nlattr)(struct sk_buff *skb, 81 const struct nf_conntrack_tuple *t); 82 /* Calculate tuple nlattr size */ 83 int (*nlattr_tuple_size)(void); 84 int (*nlattr_to_tuple)(struct nlattr *tb[], 85 struct nf_conntrack_tuple *t); 86 const struct nla_policy *nla_policy; 87 88 size_t nla_size; 89 90 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT) 91 struct { 92 size_t obj_size; 93 int (*nlattr_to_obj)(struct nlattr *tb[], 94 struct net *net, void *data); 95 int (*obj_to_nlattr)(struct sk_buff *skb, const void *data); 96 97 unsigned int nlattr_max; 98 const struct nla_policy *nla_policy; 99 } ctnl_timeout; 100 #endif 101 int *net_id; 102 /* Init l4proto pernet data */ 103 int (*init_net)(struct net *net, u_int16_t proto); 104 105 /* Return the per-net protocol part. */ 106 struct nf_proto_net *(*get_net_proto)(struct net *net); 107 108 /* Protocol name */ 109 const char *name; 110 111 /* Module (if any) which this is connected to. */ 112 struct module *me; 113 }; 114 115 /* Existing built-in generic protocol */ 116 extern struct nf_conntrack_l4proto nf_conntrack_l4proto_generic; 117 118 #define MAX_NF_CT_PROTO 256 119 120 struct nf_conntrack_l4proto *__nf_ct_l4proto_find(u_int16_t l3proto, 121 u_int8_t l4proto); 122 123 struct nf_conntrack_l4proto *nf_ct_l4proto_find_get(u_int16_t l3proto, 124 u_int8_t l4proto); 125 void nf_ct_l4proto_put(struct nf_conntrack_l4proto *p); 126 127 /* Protocol pernet registration. */ 128 int nf_ct_l4proto_pernet_register(struct net *net, 129 struct nf_conntrack_l4proto *proto); 130 void nf_ct_l4proto_pernet_unregister(struct net *net, 131 struct nf_conntrack_l4proto *proto); 132 133 /* Protocol global registration. */ 134 int nf_ct_l4proto_register(struct nf_conntrack_l4proto *proto); 135 void nf_ct_l4proto_unregister(struct nf_conntrack_l4proto *proto); 136 137 static inline void nf_ct_kfree_compat_sysctl_table(struct nf_proto_net *pn) 138 { 139 #if defined(CONFIG_SYSCTL) && defined(CONFIG_NF_CONNTRACK_PROC_COMPAT) 140 kfree(pn->ctl_compat_table); 141 pn->ctl_compat_table = NULL; 142 #endif 143 } 144 145 /* Generic netlink helpers */ 146 int nf_ct_port_tuple_to_nlattr(struct sk_buff *skb, 147 const struct nf_conntrack_tuple *tuple); 148 int nf_ct_port_nlattr_to_tuple(struct nlattr *tb[], 149 struct nf_conntrack_tuple *t); 150 int nf_ct_port_nlattr_tuple_size(void); 151 extern const struct nla_policy nf_ct_port_nla_policy[]; 152 153 #ifdef CONFIG_SYSCTL 154 #define LOG_INVALID(net, proto) \ 155 ((net)->ct.sysctl_log_invalid == (proto) || \ 156 (net)->ct.sysctl_log_invalid == IPPROTO_RAW) 157 #else 158 static inline int LOG_INVALID(struct net *net, int proto) { return 0; } 159 #endif /* CONFIG_SYSCTL */ 160 161 #endif /*_NF_CONNTRACK_PROTOCOL_H*/ 162