LXR linux/include/net/netfilter/nf_conntrack

   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
  18struct seq_file;
  19
  20struct 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);
  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        const struct nla_policy *nla_policy;
  47
  48        struct {
  49                int (*nlattr_to_obj)(struct nlattr *tb[],
  50                                     struct net *net, void *data);
  51                int (*obj_to_nlattr)(struct sk_buff *skb, const void *data);
  52
  53                u16 obj_size;
  54                u16 nlattr_max;
  55                const struct nla_policy *nla_policy;
  56        } ctnl_timeout;
  57#ifdef CONFIG_NF_CONNTRACK_PROCFS
  58        /* Print out the private part of the conntrack. */
  59        void (*print_conntrack)(struct seq_file *s, struct nf_conn *);
  60#endif
  61};
  62
  63bool icmp_pkt_to_tuple(const struct sk_buff *skb,
  64                       unsigned int dataoff,
  65                       struct net *net,
  66                       struct nf_conntrack_tuple *tuple);
  67
  68bool icmpv6_pkt_to_tuple(const struct sk_buff *skb,
  69                         unsigned int dataoff,
  70                         struct net *net,
  71                         struct nf_conntrack_tuple *tuple);
  72
  73bool nf_conntrack_invert_icmp_tuple(struct nf_conntrack_tuple *tuple,
  74                                    const struct nf_conntrack_tuple *orig);
  75bool nf_conntrack_invert_icmpv6_tuple(struct nf_conntrack_tuple *tuple,
  76                                      const struct nf_conntrack_tuple *orig);
  77
  78int nf_conntrack_inet_error(struct nf_conn *tmpl, struct sk_buff *skb,
  79                            unsigned int dataoff,
  80                            const struct nf_hook_state *state,
  81                            u8 l4proto,
  82                            union nf_inet_addr *outer_daddr);
  83
  84int nf_conntrack_icmpv4_error(struct nf_conn *tmpl,
  85                              struct sk_buff *skb,
  86                              unsigned int dataoff,
  87                              const struct nf_hook_state *state);
  88
  89int nf_conntrack_icmpv6_error(struct nf_conn *tmpl,
  90                              struct sk_buff *skb,
  91                              unsigned int dataoff,
  92                              const struct nf_hook_state *state);
  93
  94int nf_conntrack_icmp_packet(struct nf_conn *ct,
  95                             struct sk_buff *skb,
  96                             enum ip_conntrack_info ctinfo,
  97                             const struct nf_hook_state *state);
  98
  99int nf_conntrack_icmpv6_packet(struct nf_conn *ct,
 100                               struct sk_buff *skb,
 101                               enum ip_conntrack_info ctinfo,
 102                               const struct nf_hook_state *state);
 103
 104int nf_conntrack_udp_packet(struct nf_conn *ct,
 105                            struct sk_buff *skb,
 106                            unsigned int dataoff,
 107                            enum ip_conntrack_info ctinfo,
 108                            const struct nf_hook_state *state);
 109int nf_conntrack_udplite_packet(struct nf_conn *ct,
 110                                struct sk_buff *skb,
 111                                unsigned int dataoff,
 112                                enum ip_conntrack_info ctinfo,
 113                                const struct nf_hook_state *state);
 114int nf_conntrack_tcp_packet(struct nf_conn *ct,
 115                            struct sk_buff *skb,
 116                            unsigned int dataoff,
 117                            enum ip_conntrack_info ctinfo,
 118                            const struct nf_hook_state *state);
 119int nf_conntrack_dccp_packet(struct nf_conn *ct,
 120                             struct sk_buff *skb,
 121                             unsigned int dataoff,
 122                             enum ip_conntrack_info ctinfo,
 123                             const struct nf_hook_state *state);
 124int nf_conntrack_sctp_packet(struct nf_conn *ct,
 125                             struct sk_buff *skb,
 126                             unsigned int dataoff,
 127                             enum ip_conntrack_info ctinfo,
 128                             const struct nf_hook_state *state);
 129int nf_conntrack_gre_packet(struct nf_conn *ct,
 130                            struct sk_buff *skb,
 131                            unsigned int dataoff,
 132                            enum ip_conntrack_info ctinfo,
 133                            const struct nf_hook_state *state);
 134
 135void nf_conntrack_generic_init_net(struct net *net);
 136void nf_conntrack_tcp_init_net(struct net *net);
 137void nf_conntrack_udp_init_net(struct net *net);
 138void nf_conntrack_gre_init_net(struct net *net);
 139void nf_conntrack_dccp_init_net(struct net *net);
 140void nf_conntrack_sctp_init_net(struct net *net);
 141void nf_conntrack_icmp_init_net(struct net *net);
 142void nf_conntrack_icmpv6_init_net(struct net *net);
 143
 144/* Existing built-in generic protocol */
 145extern const struct nf_conntrack_l4proto nf_conntrack_l4proto_generic;
 146
 147#define MAX_NF_CT_PROTO IPPROTO_UDPLITE
 148
 149const struct nf_conntrack_l4proto *nf_ct_l4proto_find(u8 l4proto);
 150
 151/* Generic netlink helpers */
 152int nf_ct_port_tuple_to_nlattr(struct sk_buff *skb,
 153                               const struct nf_conntrack_tuple *tuple);
 154int nf_ct_port_nlattr_to_tuple(struct nlattr *tb[],
 155                               struct nf_conntrack_tuple *t);
 156unsigned int nf_ct_port_nlattr_tuple_size(void);
 157extern const struct nla_policy nf_ct_port_nla_policy[];
 158
 159#ifdef CONFIG_SYSCTL
 160__printf(3, 4) __cold
 161void nf_ct_l4proto_log_invalid(const struct sk_buff *skb,
 162                               const struct nf_conn *ct,
 163                               const char *fmt, ...);
 164__printf(5, 6) __cold
 165void nf_l4proto_log_invalid(const struct sk_buff *skb,
 166                            struct net *net,
 167                            u16 pf, u8 protonum,
 168                            const char *fmt, ...);
 169#else
 170static inline __printf(5, 6) __cold
 171void nf_l4proto_log_invalid(const struct sk_buff *skb, struct net *net,
 172                            u16 pf, u8 protonum, const char *fmt, ...) {}
 173static inline __printf(3, 4) __cold
 174void nf_ct_l4proto_log_invalid(const struct sk_buff *skb,
 175                               const struct nf_conn *ct,
 176                               const char *fmt, ...) { }
 177#endif /* CONFIG_SYSCTL */
 178
 179#if IS_ENABLED(CONFIG_NF_CONNTRACK)
 180static inline struct nf_generic_net *nf_generic_pernet(struct net *net)
 181{
 182        return &net->ct.nf_ct_proto.generic;
 183}
 184
 185static inline struct nf_tcp_net *nf_tcp_pernet(struct net *net)
 186{
 187        return &net->ct.nf_ct_proto.tcp;
 188}
 189
 190static inline struct nf_udp_net *nf_udp_pernet(struct net *net)
 191{
 192        return &net->ct.nf_ct_proto.udp;
 193}
 194
 195static inline struct nf_icmp_net *nf_icmp_pernet(struct net *net)
 196{
 197        return &net->ct.nf_ct_proto.icmp;
 198}
 199
 200static inline struct nf_icmp_net *nf_icmpv6_pernet(struct net *net)
 201{
 202        return &net->ct.nf_ct_proto.icmpv6;
 203}
 204#endif
 205
 206#ifdef CONFIG_NF_CT_PROTO_DCCP
 207static inline struct nf_dccp_net *nf_dccp_pernet(struct net *net)
 208{
 209        return &net->ct.nf_ct_proto.dccp;
 210}
 211#endif
 212
 213#ifdef CONFIG_NF_CT_PROTO_SCTP
 214static 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
 221static 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