1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _NF_LOG_H
3 #define _NF_LOG_H
4 
5 #include <linux/netfilter.h>
6 #include <linux/netfilter/nf_log.h>
7 
8 /* Log tcp sequence, tcp options, ip options and uid owning local socket */
9 #define NF_LOG_DEFAULT_MASK	0x0f
10 
11 /* This flag indicates that copy_len field in nf_loginfo is set */
12 #define NF_LOG_F_COPY_LEN	0x1
13 
14 enum nf_log_type {
15 	NF_LOG_TYPE_LOG		= 0,
16 	NF_LOG_TYPE_ULOG,
17 	NF_LOG_TYPE_MAX
18 };
19 
20 struct nf_loginfo {
21 	u_int8_t type;
22 	union {
23 		struct {
24 			/* copy_len will be used iff you set
25 			 * NF_LOG_F_COPY_LEN in flags
26 			 */
27 			u_int32_t copy_len;
28 			u_int16_t group;
29 			u_int16_t qthreshold;
30 			u_int16_t flags;
31 		} ulog;
32 		struct {
33 			u_int8_t level;
34 			u_int8_t logflags;
35 		} log;
36 	} u;
37 };
38 
39 typedef void nf_logfn(struct net *net,
40 		      u_int8_t pf,
41 		      unsigned int hooknum,
42 		      const struct sk_buff *skb,
43 		      const struct net_device *in,
44 		      const struct net_device *out,
45 		      const struct nf_loginfo *li,
46 		      const char *prefix);
47 
48 struct nf_logger {
49 	char			*name;
50 	enum nf_log_type	type;
51 	nf_logfn 		*logfn;
52 	struct module		*me;
53 };
54 
55 /* sysctl_nf_log_all_netns - allow LOG target in all network namespaces */
56 extern int sysctl_nf_log_all_netns;
57 
58 /* Function to register/unregister log function. */
59 int nf_log_register(u_int8_t pf, struct nf_logger *logger);
60 void nf_log_unregister(struct nf_logger *logger);
61 
62 int nf_log_set(struct net *net, u_int8_t pf, const struct nf_logger *logger);
63 void nf_log_unset(struct net *net, const struct nf_logger *logger);
64 
65 int nf_log_bind_pf(struct net *net, u_int8_t pf,
66 		   const struct nf_logger *logger);
67 void nf_log_unbind_pf(struct net *net, u_int8_t pf);
68 
69 int nf_logger_find_get(int pf, enum nf_log_type type);
70 void nf_logger_put(int pf, enum nf_log_type type);
71 void nf_logger_request_module(int pf, enum nf_log_type type);
72 
73 #define MODULE_ALIAS_NF_LOGGER(family, type) \
74 	MODULE_ALIAS("nf-logger-" __stringify(family) "-" __stringify(type))
75 
76 /* Calls the registered backend logging function */
77 __printf(8, 9)
78 void nf_log_packet(struct net *net,
79 		   u_int8_t pf,
80 		   unsigned int hooknum,
81 		   const struct sk_buff *skb,
82 		   const struct net_device *in,
83 		   const struct net_device *out,
84 		   const struct nf_loginfo *li,
85 		   const char *fmt, ...);
86 
87 __printf(8, 9)
88 void nf_log_trace(struct net *net,
89 		  u_int8_t pf,
90 		  unsigned int hooknum,
91 		  const struct sk_buff *skb,
92 		  const struct net_device *in,
93 		  const struct net_device *out,
94 		  const struct nf_loginfo *li,
95 		  const char *fmt, ...);
96 
97 struct nf_log_buf;
98 
99 struct nf_log_buf *nf_log_buf_open(void);
100 __printf(2, 3) int nf_log_buf_add(struct nf_log_buf *m, const char *f, ...);
101 void nf_log_buf_close(struct nf_log_buf *m);
102 
103 /* common logging functions */
104 int nf_log_dump_udp_header(struct nf_log_buf *m, const struct sk_buff *skb,
105 			   u8 proto, int fragment, unsigned int offset);
106 int nf_log_dump_tcp_header(struct nf_log_buf *m, const struct sk_buff *skb,
107 			   u8 proto, int fragment, unsigned int offset,
108 			   unsigned int logflags);
109 void nf_log_dump_sk_uid_gid(struct net *net, struct nf_log_buf *m,
110 			    struct sock *sk);
111 void nf_log_dump_vlan(struct nf_log_buf *m, const struct sk_buff *skb);
112 void nf_log_dump_packet_common(struct nf_log_buf *m, u_int8_t pf,
113 			       unsigned int hooknum, const struct sk_buff *skb,
114 			       const struct net_device *in,
115 			       const struct net_device *out,
116 			       const struct nf_loginfo *loginfo,
117 			       const char *prefix);
118 void nf_log_l2packet(struct net *net, u_int8_t pf,
119 		     __be16 protocol,
120 		     unsigned int hooknum,
121 		     const struct sk_buff *skb,
122 		     const struct net_device *in,
123 		     const struct net_device *out,
124 		     const struct nf_loginfo *loginfo, const char *prefix);
125 
126 #endif /* _NF_LOG_H */
127