include/linux/netfilter/nfnetlink.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _NFNETLINK_H
   3 #define _NFNETLINK_H
   4
   5 #include <linux/netlink.h>
   6 #include <linux/capability.h>
   7 #include <net/netlink.h>
   8 #include <uapi/linux/netfilter/nfnetlink.h>
   9
  10 struct nfnl_callback {
  11         int (*call)(struct net *net, struct sock *nl, struct sk_buff *skb,
  12                     const struct nlmsghdr *nlh,
  13                     const struct nlattr * const cda[],
  14                     struct netlink_ext_ack *extack);
  15         int (*call_rcu)(struct net *net, struct sock *nl, struct sk_buff *skb,
  16                         const struct nlmsghdr *nlh,
  17                         const struct nlattr * const cda[],
  18                         struct netlink_ext_ack *extack);
  19         int (*call_batch)(struct net *net, struct sock *nl, struct sk_buff *skb,
  20                           const struct nlmsghdr *nlh,
  21                           const struct nlattr * const cda[],
  22                           struct netlink_ext_ack *extack);
  23         const struct nla_policy *policy;        /* netlink attribute policy */
  24         const u_int16_t attr_count;             /* number of nlattr's */
  25 };
  26
  27 enum nfnl_abort_action {
  28         NFNL_ABORT_NONE         = 0,
  29         NFNL_ABORT_AUTOLOAD,
  30         NFNL_ABORT_VALIDATE,
  31 };
  32
  33 struct nfnetlink_subsystem {
  34         const char *name;
  35         __u8 subsys_id;                 /* nfnetlink subsystem ID */
  36         __u8 cb_count;                  /* number of callbacks */
  37         const struct nfnl_callback *cb; /* callback for individual types */
  38         struct module *owner;
  39         int (*commit)(struct net *net, struct sk_buff *skb);
  40         int (*abort)(struct net *net, struct sk_buff *skb,
  41                      enum nfnl_abort_action action);
  42         void (*cleanup)(struct net *net);
  43         bool (*valid_genid)(struct net *net, u32 genid);
  44 };
  45
  46 int nfnetlink_subsys_register(const struct nfnetlink_subsystem *n);
  47 int nfnetlink_subsys_unregister(const struct nfnetlink_subsystem *n);
  48
  49 int nfnetlink_has_listeners(struct net *net, unsigned int group);
  50 int nfnetlink_send(struct sk_buff *skb, struct net *net, u32 portid,
  51                    unsigned int group, int echo, gfp_t flags);
  52 int nfnetlink_set_err(struct net *net, u32 portid, u32 group, int error);
  53 int nfnetlink_unicast(struct sk_buff *skb, struct net *net, u32 portid);
  54
  55 static inline u16 nfnl_msg_type(u8 subsys, u8 msg_type)
  56 {
  57         return subsys << 8 | msg_type;
  58 }
  59
  60 void nfnl_lock(__u8 subsys_id);
  61 void nfnl_unlock(__u8 subsys_id);
  62 #ifdef CONFIG_PROVE_LOCKING
  63 bool lockdep_nfnl_is_held(__u8 subsys_id);
  64 #else
  65 static inline bool lockdep_nfnl_is_held(__u8 subsys_id)
  66 {
  67         return true;
  68 }
  69 #endif /* CONFIG_PROVE_LOCKING */
  70
  71 #define MODULE_ALIAS_NFNL_SUBSYS(subsys) \
  72         MODULE_ALIAS("nfnetlink-subsys-" __stringify(subsys))
  73
  74 #endif  /* _NFNETLINK_H */