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_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 18 enum nfnl_callback_type { 19 NFNL_CB_UNSPEC = 0, 20 NFNL_CB_MUTEX, 21 NFNL_CB_RCU, 22 NFNL_CB_BATCH, 23 }; 24 25 struct 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 33 enum nfnl_abort_action { 34 NFNL_ABORT_NONE = 0, 35 NFNL_ABORT_AUTOLOAD, 36 NFNL_ABORT_VALIDATE, 37 }; 38 39 struct 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 52 int nfnetlink_subsys_register(const struct nfnetlink_subsystem *n); 53 int nfnetlink_subsys_unregister(const struct nfnetlink_subsystem *n); 54 55 int nfnetlink_has_listeners(struct net *net, unsigned int group); 56 int nfnetlink_send(struct sk_buff *skb, struct net *net, u32 portid, 57 unsigned int group, int echo, gfp_t flags); 58 int nfnetlink_set_err(struct net *net, u32 portid, u32 group, int error); 59 int nfnetlink_unicast(struct sk_buff *skb, struct net *net, u32 portid); 60 void nfnetlink_broadcast(struct net *net, struct sk_buff *skb, __u32 portid, 61 __u32 group, gfp_t allocation); 62 63 static inline u16 nfnl_msg_type(u8 subsys, u8 msg_type) 64 { 65 return subsys << 8 | msg_type; 66 } 67 68 static 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 79 static 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 95 void nfnl_lock(__u8 subsys_id); 96 void nfnl_unlock(__u8 subsys_id); 97 #ifdef CONFIG_PROVE_LOCKING 98 bool lockdep_nfnl_is_held(__u8 subsys_id); 99 #else 100 static 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