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 16 struct seq_file; 17 18 struct nf_conntrack_l4proto { 19 /* L3 Protocol number. */ 20 u_int16_t l3proto; 21 22 /* L4 Protocol number. */ 23 u_int8_t l4proto; 24 25 /* Try to fill in the third arg: dataoff is offset past network protocol 26 hdr. Return true if possible. */ 27 bool (*pkt_to_tuple)(const struct sk_buff *skb, unsigned int dataoff, 28 struct nf_conntrack_tuple *tuple); 29 30 /* Invert the per-proto part of the tuple: ie. turn xmit into reply. 31 * Some packets can't be inverted: return 0 in that case. 32 */ 33 bool (*invert_tuple)(struct nf_conntrack_tuple *inverse, 34 const struct nf_conntrack_tuple *orig); 35 36 /* Returns verdict for packet, or -1 for invalid. */ 37 int (*packet)(struct nf_conn *ct, 38 const struct sk_buff *skb, 39 unsigned int dataoff, 40 enum ip_conntrack_info ctinfo, 41 u_int8_t pf, 42 unsigned int hooknum, 43 unsigned int *timeouts); 44 45 /* Called when a new connection for this protocol found; 46 * returns TRUE if it's OK. If so, packet() called next. */ 47 bool (*new)(struct nf_conn *ct, const struct sk_buff *skb, 48 unsigned int dataoff, unsigned int *timeouts); 49 50 /* Called when a conntrack entry is destroyed */ 51 void (*destroy)(struct nf_conn *ct); 52 53 int (*error)(struct net *net, struct nf_conn *tmpl, struct sk_buff *skb, 54 unsigned int dataoff, enum ip_conntrack_info *ctinfo, 55 u_int8_t pf, unsigned int hooknum); 56 57 /* Print out the per-protocol part of the tuple. Return like seq_* */ 58 int (*print_tuple)(struct seq_file *s, 59 const struct nf_conntrack_tuple *); 60 61 /* Print out the private part of the conntrack. */ 62 int (*print_conntrack)(struct seq_file *s, struct nf_conn *); 63 64 /* Return the array of timeouts for this protocol. */ 65 unsigned int *(*get_timeouts)(struct net *net); 66 67 /* convert protoinfo to nfnetink attributes */ 68 int (*to_nlattr)(struct sk_buff *skb, struct nlattr *nla, 69 struct nf_conn *ct); 70 /* Calculate protoinfo nlattr size */ 71 int (*nlattr_size)(void); 72 73 /* convert nfnetlink attributes to protoinfo */ 74 int (*from_nlattr)(struct nlattr *tb[], struct nf_conn *ct); 75 76 int (*tuple_to_nlattr)(struct sk_buff *skb, 77 const struct nf_conntrack_tuple *t); 78 /* Calculate tuple nlattr size */ 79 int (*nlattr_tuple_size)(void); 80 int (*nlattr_to_tuple)(struct nlattr *tb[], 81 struct nf_conntrack_tuple *t); 82 const struct nla_policy *nla_policy; 83 84 size_t nla_size; 85 86 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT) 87 struct { 88 size_t obj_size; 89 int (*nlattr_to_obj)(struct nlattr *tb[], void *data); 90 int (*obj_to_nlattr)(struct sk_buff *skb, const void *data); 91 92 unsigned int nlattr_max; 93 const struct nla_policy *nla_policy; 94 } ctnl_timeout; 95 #endif 96 97 #ifdef CONFIG_SYSCTL 98 struct ctl_table_header **ctl_table_header; 99 struct ctl_table *ctl_table; 100 unsigned int *ctl_table_users; 101 #ifdef CONFIG_NF_CONNTRACK_PROC_COMPAT 102 struct ctl_table_header *ctl_compat_table_header; 103 struct ctl_table *ctl_compat_table; 104 #endif 105 #endif 106 /* Protocol name */ 107 const char *name; 108 109 /* Module (if any) which this is connected to. */ 110 struct module *me; 111 }; 112 113 /* Existing built-in generic protocol */ 114 extern struct nf_conntrack_l4proto nf_conntrack_l4proto_generic; 115 116 #define MAX_NF_CT_PROTO 256 117 118 extern struct nf_conntrack_l4proto * 119 __nf_ct_l4proto_find(u_int16_t l3proto, u_int8_t l4proto); 120 121 /* Protocol registration. */ 122 extern int nf_conntrack_l4proto_register(struct nf_conntrack_l4proto *proto); 123 extern void nf_conntrack_l4proto_unregister(struct nf_conntrack_l4proto *proto); 124 125 /* Generic netlink helpers */ 126 extern int nf_ct_port_tuple_to_nlattr(struct sk_buff *skb, 127 const struct nf_conntrack_tuple *tuple); 128 extern int nf_ct_port_nlattr_to_tuple(struct nlattr *tb[], 129 struct nf_conntrack_tuple *t); 130 extern int nf_ct_port_nlattr_tuple_size(void); 131 extern const struct nla_policy nf_ct_port_nla_policy[]; 132 133 #ifdef CONFIG_SYSCTL 134 #ifdef DEBUG_INVALID_PACKETS 135 #define LOG_INVALID(net, proto) \ 136 ((net)->ct.sysctl_log_invalid == (proto) || \ 137 (net)->ct.sysctl_log_invalid == IPPROTO_RAW) 138 #else 139 #define LOG_INVALID(net, proto) \ 140 (((net)->ct.sysctl_log_invalid == (proto) || \ 141 (net)->ct.sysctl_log_invalid == IPPROTO_RAW) \ 142 && net_ratelimit()) 143 #endif 144 #else 145 static inline int LOG_INVALID(struct net *net, int proto) { return 0; } 146 #endif /* CONFIG_SYSCTL */ 147 148 #endif /*_NF_CONNTRACK_PROTOCOL_H*/ 149