LXR linux/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
  10struct nfnl_info {
  11        struct net              *net;
  12        struct sock             *sk;
  13        const struct nlmsghdr   *nlh;
  14        const struct nfgenmsg   *nfmsg;
  15        struct netlink_ext_ack  *extack;
  16};
  17
  18enum nfnl_callback_type {
  19        NFNL_CB_UNSPEC  = 0,
  20        NFNL_CB_MUTEX,
  21        NFNL_CB_RCU,
  22        NFNL_CB_BATCH,
  23};
  24
  25struct nfnl_callback {
  26        int (*call)(struct sk_buff *skb, const struct nfnl_info *info,
  27                    const struct nlattr * const cda[]);
  28        const struct nla_policy *policy;
  29        enum nfnl_callback_type type;
  30        __u16                   attr_count;
  31};
  32
  33enum nfnl_abort_action {
  34        NFNL_ABORT_NONE         = 0,
  35        NFNL_ABORT_AUTOLOAD,
  36        NFNL_ABORT_VALIDATE,
  37};
  38
  39struct nfnetlink_subsystem {
  40        const char *name;
  41        __u8 subsys_id;                 /* nfnetlink subsystem ID */
  42        __u8 cb_count;                  /* number of callbacks */
  43        const struct nfnl_callback *cb; /* callback for individual types */
  44        struct module *owner;
  45        int (*commit)(struct net *net, struct sk_buff *skb);
  46        int (*abort)(struct net *net, struct sk_buff *skb,
  47                     enum nfnl_abort_action action);
  48        void (*cleanup)(struct net *net);
  49        bool (*valid_genid)(struct net *net, u32 genid);
  50};
  51
  52int nfnetlink_subsys_register(const struct nfnetlink_subsystem *n);
  53int nfnetlink_subsys_unregister(const struct nfnetlink_subsystem *n);
  54
  55int nfnetlink_has_listeners(struct net *net, unsigned int group);
  56int nfnetlink_send(struct sk_buff *skb, struct net *net, u32 portid,
  57                   unsigned int group, int echo, gfp_t flags);
  58int nfnetlink_set_err(struct net *net, u32 portid, u32 group, int error);
  59int nfnetlink_unicast(struct sk_buff *skb, struct net *net, u32 portid);
  60void nfnetlink_broadcast(struct net *net, struct sk_buff *skb, __u32 portid,
  61                         __u32 group, gfp_t allocation);
  62
  63static inline u16 nfnl_msg_type(u8 subsys, u8 msg_type)
  64{
  65        return subsys << 8 | msg_type;
  66}
  67
  68static inline void nfnl_fill_hdr(struct nlmsghdr *nlh, u8 family, u8 version,
  69                                 __be16 res_id)
  70{
  71        struct nfgenmsg *nfmsg;
  72
  73        nfmsg = nlmsg_data(nlh);
  74        nfmsg->nfgen_family = family;
  75        nfmsg->version = version;
  76        nfmsg->res_id = res_id;
  77}
  78
  79static inline struct nlmsghdr *nfnl_msg_put(struct sk_buff *skb, u32 portid,
  80                                            u32 seq, int type, int flags,
  81                                            u8 family, u8 version,
  82                                            __be16 res_id)
  83{
  84        struct nlmsghdr *nlh;
  85
  86        nlh = nlmsg_put(skb, portid, seq, type, sizeof(struct nfgenmsg), flags);
  87        if (!nlh)
  88                return NULL;
  89
  90        nfnl_fill_hdr(nlh, family, version, res_id);
  91
  92        return nlh;
  93}
  94
  95void nfnl_lock(__u8 subsys_id);
  96void nfnl_unlock(__u8 subsys_id);
  97#ifdef CONFIG_PROVE_LOCKING
  98bool lockdep_nfnl_is_held(__u8 subsys_id);
  99#else
 100static inline bool lockdep_nfnl_is_held(__u8 subsys_id)
 101{
 102        return true;
 103}
 104#endif /* CONFIG_PROVE_LOCKING */
 105
 106#define MODULE_ALIAS_NFNL_SUBSYS(subsys) \
 107        MODULE_ALIAS("nfnetlink-subsys-" __stringify(subsys))
 108
 109#endif  /* _NFNETLINK_H */
 110