include/net/netfilter/nf_conntrack_l4proto.h

   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 nfnetink 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_udplite_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_tcp_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_dccp_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 int nf_conntrack_sctp_packet(struct nf_conn *ct,
 126                              struct sk_buff *skb,
 127                              unsigned int dataoff,
 128                              enum ip_conntrack_info ctinfo,
 129                              const struct nf_hook_state *state);
 130 int nf_conntrack_gre_packet(struct nf_conn *ct,
 131                             struct sk_buff *skb,
 132                             unsigned int dataoff,
 133                             enum ip_conntrack_info ctinfo,
 134                             const struct nf_hook_state *state);
 135
 136 void nf_conntrack_generic_init_net(struct net *net);
 137 void nf_conntrack_tcp_init_net(struct net *net);
 138 void nf_conntrack_udp_init_net(struct net *net);
 139 void nf_conntrack_gre_init_net(struct net *net);
 140 void nf_conntrack_dccp_init_net(struct net *net);
 141 void nf_conntrack_sctp_init_net(struct net *net);
 142 void nf_conntrack_icmp_init_net(struct net *net);
 143 void nf_conntrack_icmpv6_init_net(struct net *net);
 144
 145 /* Existing built-in generic protocol */
 146 extern const struct nf_conntrack_l4proto nf_conntrack_l4proto_generic;
 147
 148 #define MAX_NF_CT_PROTO IPPROTO_UDPLITE
 149
 150 const struct nf_conntrack_l4proto *nf_ct_l4proto_find(u8 l4proto);
 151
 152 /* Generic netlink helpers */
 153 int nf_ct_port_tuple_to_nlattr(struct sk_buff *skb,
 154                                const struct nf_conntrack_tuple *tuple);
 155 int nf_ct_port_nlattr_to_tuple(struct nlattr *tb[],
 156                                struct nf_conntrack_tuple *t,
 157                                u_int32_t flags);
 158 unsigned int nf_ct_port_nlattr_tuple_size(void);
 159 extern const struct nla_policy nf_ct_port_nla_policy[];
 160
 161 #ifdef CONFIG_SYSCTL
 162 __printf(3, 4) __cold
 163 void nf_ct_l4proto_log_invalid(const struct sk_buff *skb,
 164                                const struct nf_conn *ct,
 165                                const char *fmt, ...);
 166 __printf(5, 6) __cold
 167 void nf_l4proto_log_invalid(const struct sk_buff *skb,
 168                             struct net *net,
 169                             u16 pf, u8 protonum,
 170                             const char *fmt, ...);
 171 #else
 172 static inline __printf(5, 6) __cold
 173 void nf_l4proto_log_invalid(const struct sk_buff *skb, struct net *net,
 174                             u16 pf, u8 protonum, const char *fmt, ...) {}
 175 static inline __printf(3, 4) __cold
 176 void nf_ct_l4proto_log_invalid(const struct sk_buff *skb,
 177                                const struct nf_conn *ct,
 178                                const char *fmt, ...) { }
 179 #endif /* CONFIG_SYSCTL */
 180
 181 #if IS_ENABLED(CONFIG_NF_CONNTRACK)
 182 static inline struct nf_generic_net *nf_generic_pernet(struct net *net)
 183 {
 184         return &net->ct.nf_ct_proto.generic;
 185 }
 186
 187 static inline struct nf_tcp_net *nf_tcp_pernet(struct net *net)
 188 {
 189         return &net->ct.nf_ct_proto.tcp;
 190 }
 191
 192 static inline struct nf_udp_net *nf_udp_pernet(struct net *net)
 193 {
 194         return &net->ct.nf_ct_proto.udp;
 195 }
 196
 197 static inline struct nf_icmp_net *nf_icmp_pernet(struct net *net)
 198 {
 199         return &net->ct.nf_ct_proto.icmp;
 200 }
 201
 202 static inline struct nf_icmp_net *nf_icmpv6_pernet(struct net *net)
 203 {
 204         return &net->ct.nf_ct_proto.icmpv6;
 205 }
 206
 207 /* Caller must check nf_ct_protonum(ct) is IPPROTO_TCP before calling. */
 208 static inline void nf_ct_set_tcp_be_liberal(struct nf_conn *ct)
 209 {
 210         ct->proto.tcp.seen[0].flags |= IP_CT_TCP_FLAG_BE_LIBERAL;
 211         ct->proto.tcp.seen[1].flags |= IP_CT_TCP_FLAG_BE_LIBERAL;
 212 }
 213
 214 /* Caller must check nf_ct_protonum(ct) is IPPROTO_TCP before calling. */
 215 static inline bool nf_conntrack_tcp_established(const struct nf_conn *ct)
 216 {
 217         return ct->proto.tcp.state == TCP_CONNTRACK_ESTABLISHED &&
 218                test_bit(IPS_ASSURED_BIT, &ct->status);
 219 }
 220 #endif
 221
 222 #ifdef CONFIG_NF_CT_PROTO_DCCP
 223 static inline struct nf_dccp_net *nf_dccp_pernet(struct net *net)
 224 {
 225         return &net->ct.nf_ct_proto.dccp;
 226 }
 227 #endif
 228
 229 #ifdef CONFIG_NF_CT_PROTO_SCTP
 230 static inline struct nf_sctp_net *nf_sctp_pernet(struct net *net)
 231 {
 232         return &net->ct.nf_ct_proto.sctp;
 233 }
 234 #endif
 235
 236 #ifdef CONFIG_NF_CT_PROTO_GRE
 237 static inline struct nf_gre_net *nf_gre_pernet(struct net *net)
 238 {
 239         return &net->ct.nf_ct_proto.gre;
 240 }
 241 #endif
 242
 243 #endif /*_NF_CONNTRACK_PROTOCOL_H*/