1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * Header for use in defining a given L4 protocol for connection tracking. 4 * 5 * 16 Dec 2003: Yasuyuki Kozakai @USAGI <yasuyuki.kozakai@toshiba.co.jp> 6 * - generalized L3 protocol dependent part. 7 * 8 * Derived from include/linux/netfiter_ipv4/ip_conntrack_protcol.h 9 */ 10 11 #ifndef _NF_CONNTRACK_L4PROTO_H 12 #define _NF_CONNTRACK_L4PROTO_H 13 #include <linux/netlink.h> 14 #include <net/netlink.h> 15 #include <net/netfilter/nf_conntrack.h> 16 #include <net/netns/generic.h> 17 18 struct seq_file; 19 20 struct nf_conntrack_l4proto { 21 /* L4 Protocol number. */ 22 u_int8_t l4proto; 23 24 /* Resolve clashes on insertion races. */ 25 bool allow_clash; 26 27 /* protoinfo nlattr size, closes a hole */ 28 u16 nlattr_size; 29 30 /* called by gc worker if table is full */ 31 bool (*can_early_drop)(const struct nf_conn *ct); 32 33 /* convert protoinfo to nfnetlink attributes */ 34 int (*to_nlattr)(struct sk_buff *skb, struct nlattr *nla, 35 struct nf_conn *ct, bool destroy); 36 37 /* convert nfnetlink attributes to protoinfo */ 38 int (*from_nlattr)(struct nlattr *tb[], struct nf_conn *ct); 39 40 int (*tuple_to_nlattr)(struct sk_buff *skb, 41 const struct nf_conntrack_tuple *t); 42 /* Calculate tuple nlattr size */ 43 unsigned int (*nlattr_tuple_size)(void); 44 int (*nlattr_to_tuple)(struct nlattr *tb[], 45 struct nf_conntrack_tuple *t, 46 u_int32_t flags); 47 const struct nla_policy *nla_policy; 48 49 struct { 50 int (*nlattr_to_obj)(struct nlattr *tb[], 51 struct net *net, void *data); 52 int (*obj_to_nlattr)(struct sk_buff *skb, const void *data); 53 54 u16 obj_size; 55 u16 nlattr_max; 56 const struct nla_policy *nla_policy; 57 } ctnl_timeout; 58 #ifdef CONFIG_NF_CONNTRACK_PROCFS 59 /* Print out the private part of the conntrack. */ 60 void (*print_conntrack)(struct seq_file *s, struct nf_conn *); 61 #endif 62 }; 63 64 bool icmp_pkt_to_tuple(const struct sk_buff *skb, 65 unsigned int dataoff, 66 struct net *net, 67 struct nf_conntrack_tuple *tuple); 68 69 bool icmpv6_pkt_to_tuple(const struct sk_buff *skb, 70 unsigned int dataoff, 71 struct net *net, 72 struct nf_conntrack_tuple *tuple); 73 74 bool nf_conntrack_invert_icmp_tuple(struct nf_conntrack_tuple *tuple, 75 const struct nf_conntrack_tuple *orig); 76 bool nf_conntrack_invert_icmpv6_tuple(struct nf_conntrack_tuple *tuple, 77 const struct nf_conntrack_tuple *orig); 78 79 int nf_conntrack_inet_error(struct nf_conn *tmpl, struct sk_buff *skb, 80 unsigned int dataoff, 81 const struct nf_hook_state *state, 82 u8 l4proto, 83 union nf_inet_addr *outer_daddr); 84 85 int nf_conntrack_icmpv4_error(struct nf_conn *tmpl, 86 struct sk_buff *skb, 87 unsigned int dataoff, 88 const struct nf_hook_state *state); 89 90 int nf_conntrack_icmpv6_error(struct nf_conn *tmpl, 91 struct sk_buff *skb, 92 unsigned int dataoff, 93 const struct nf_hook_state *state); 94 95 int nf_conntrack_icmp_packet(struct nf_conn *ct, 96 struct sk_buff *skb, 97 enum ip_conntrack_info ctinfo, 98 const struct nf_hook_state *state); 99 100 int nf_conntrack_icmpv6_packet(struct nf_conn *ct, 101 struct sk_buff *skb, 102 enum ip_conntrack_info ctinfo, 103 const struct nf_hook_state *state); 104 105 int nf_conntrack_udp_packet(struct nf_conn *ct, 106 struct sk_buff *skb, 107 unsigned int dataoff, 108 enum ip_conntrack_info ctinfo, 109 const struct nf_hook_state *state); 110 int nf_conntrack_tcp_packet(struct nf_conn *ct, 111 struct sk_buff *skb, 112 unsigned int dataoff, 113 enum ip_conntrack_info ctinfo, 114 const struct nf_hook_state *state); 115 int nf_conntrack_sctp_packet(struct nf_conn *ct, 116 struct sk_buff *skb, 117 unsigned int dataoff, 118 enum ip_conntrack_info ctinfo, 119 const struct nf_hook_state *state); 120 int nf_conntrack_gre_packet(struct nf_conn *ct, 121 struct sk_buff *skb, 122 unsigned int dataoff, 123 enum ip_conntrack_info ctinfo, 124 const struct nf_hook_state *state); 125 126 void nf_conntrack_generic_init_net(struct net *net); 127 void nf_conntrack_tcp_init_net(struct net *net); 128 void nf_conntrack_udp_init_net(struct net *net); 129 void nf_conntrack_gre_init_net(struct net *net); 130 void nf_conntrack_sctp_init_net(struct net *net); 131 void nf_conntrack_icmp_init_net(struct net *net); 132 void nf_conntrack_icmpv6_init_net(struct net *net); 133 134 /* Existing built-in generic protocol */ 135 extern const struct nf_conntrack_l4proto nf_conntrack_l4proto_generic; 136 137 const struct nf_conntrack_l4proto *nf_ct_l4proto_find(u8 l4proto); 138 139 /* Generic netlink helpers */ 140 int nf_ct_port_tuple_to_nlattr(struct sk_buff *skb, 141 const struct nf_conntrack_tuple *tuple); 142 int nf_ct_port_nlattr_to_tuple(struct nlattr *tb[], 143 struct nf_conntrack_tuple *t, 144 u_int32_t flags); 145 unsigned int nf_ct_port_nlattr_tuple_size(void); 146 extern const struct nla_policy nf_ct_port_nla_policy[]; 147 148 #ifdef CONFIG_SYSCTL 149 __printf(4, 5) __cold 150 void nf_ct_l4proto_log_invalid(const struct sk_buff *skb, 151 const struct nf_conn *ct, 152 const struct nf_hook_state *state, 153 const char *fmt, ...); 154 __printf(4, 5) __cold 155 void nf_l4proto_log_invalid(const struct sk_buff *skb, 156 const struct nf_hook_state *state, 157 u8 protonum, 158 const char *fmt, ...); 159 #else 160 static inline __printf(4, 5) __cold 161 void nf_l4proto_log_invalid(const struct sk_buff *skb, 162 const struct nf_hook_state *state, 163 u8 protonum, 164 const char *fmt, ...) {} 165 static inline __printf(4, 5) __cold 166 void nf_ct_l4proto_log_invalid(const struct sk_buff *skb, 167 const struct nf_conn *ct, 168 const struct nf_hook_state *state, 169 const char *fmt, ...) { } 170 #endif /* CONFIG_SYSCTL */ 171 172 #if IS_ENABLED(CONFIG_NF_CONNTRACK) 173 static inline struct nf_generic_net *nf_generic_pernet(struct net *net) 174 { 175 return &net->ct.nf_ct_proto.generic; 176 } 177 178 static inline struct nf_tcp_net *nf_tcp_pernet(struct net *net) 179 { 180 return &net->ct.nf_ct_proto.tcp; 181 } 182 183 static inline struct nf_udp_net *nf_udp_pernet(struct net *net) 184 { 185 return &net->ct.nf_ct_proto.udp; 186 } 187 188 static inline struct nf_icmp_net *nf_icmp_pernet(struct net *net) 189 { 190 return &net->ct.nf_ct_proto.icmp; 191 } 192 193 static inline struct nf_icmp_net *nf_icmpv6_pernet(struct net *net) 194 { 195 return &net->ct.nf_ct_proto.icmpv6; 196 } 197 198 /* Caller must check nf_ct_protonum(ct) is IPPROTO_TCP before calling. */ 199 static inline void nf_ct_set_tcp_be_liberal(struct nf_conn *ct) 200 { 201 ct->proto.tcp.seen[0].flags |= IP_CT_TCP_FLAG_BE_LIBERAL; 202 ct->proto.tcp.seen[1].flags |= IP_CT_TCP_FLAG_BE_LIBERAL; 203 } 204 205 /* Caller must check nf_ct_protonum(ct) is IPPROTO_TCP before calling. */ 206 static inline bool nf_conntrack_tcp_established(const struct nf_conn *ct) 207 { 208 return ct->proto.tcp.state == TCP_CONNTRACK_ESTABLISHED && 209 test_bit(IPS_ASSURED_BIT, &ct->status); 210 } 211 #endif 212 213 #ifdef CONFIG_NF_CT_PROTO_SCTP 214 static inline struct nf_sctp_net *nf_sctp_pernet(struct net *net) 215 { 216 return &net->ct.nf_ct_proto.sctp; 217 } 218 #endif 219 220 #ifdef CONFIG_NF_CT_PROTO_GRE 221 static inline struct nf_gre_net *nf_gre_pernet(struct net *net) 222 { 223 return &net->ct.nf_ct_proto.gre; 224 } 225 #endif 226 227 #endif /*_NF_CONNTRACK_PROTOCOL_H*/ 228