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
18 struct seq_file;
19
20 struct 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, bool destroy);
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 u_int32_t flags);
47 const struct nla_policy *nla_policy;
48
49 struct {
50 int (*nlattr_to_obj)(struct nlattr *tb[],
51 struct net *net, void *data);
52 int (*obj_to_nlattr)(struct sk_buff *skb, const void *data);
53
54 u16 obj_size;
55 u16 nlattr_max;
56 const struct nla_policy *nla_policy;
57 } ctnl_timeout;
58 #ifdef CONFIG_NF_CONNTRACK_PROCFS
59 /* Print out the private part of the conntrack. */
60 void (*print_conntrack)(struct seq_file *s, struct nf_conn *);
61 #endif
62 };
63
64 bool icmp_pkt_to_tuple(const struct sk_buff *skb,
65 unsigned int dataoff,
66 struct net *net,
67 struct nf_conntrack_tuple *tuple);
68
69 bool icmpv6_pkt_to_tuple(const struct sk_buff *skb,
70 unsigned int dataoff,
71 struct net *net,
72 struct nf_conntrack_tuple *tuple);
73
74 bool nf_conntrack_invert_icmp_tuple(struct nf_conntrack_tuple *tuple,
75 const struct nf_conntrack_tuple *orig);
76 bool nf_conntrack_invert_icmpv6_tuple(struct nf_conntrack_tuple *tuple,
77 const struct nf_conntrack_tuple *orig);
78
79 int nf_conntrack_inet_error(struct nf_conn *tmpl, struct sk_buff *skb,
80 unsigned int dataoff,
81 const struct nf_hook_state *state,
82 u8 l4proto,
83 union nf_inet_addr *outer_daddr);
84
85 int nf_conntrack_icmpv4_error(struct nf_conn *tmpl,
86 struct sk_buff *skb,
87 unsigned int dataoff,
88 const struct nf_hook_state *state);
89
90 int nf_conntrack_icmpv6_error(struct nf_conn *tmpl,
91 struct sk_buff *skb,
92 unsigned int dataoff,
93 const struct nf_hook_state *state);
94
95 int nf_conntrack_icmp_packet(struct nf_conn *ct,
96 struct sk_buff *skb,
97 enum ip_conntrack_info ctinfo,
98 const struct nf_hook_state *state);
99
100 int nf_conntrack_icmpv6_packet(struct nf_conn *ct,
101 struct sk_buff *skb,
102 enum ip_conntrack_info ctinfo,
103 const struct nf_hook_state *state);
104
105 int nf_conntrack_udp_packet(struct nf_conn *ct,
106 struct sk_buff *skb,
107 unsigned int dataoff,
108 enum ip_conntrack_info ctinfo,
109 const struct nf_hook_state *state);
110 int nf_conntrack_udplite_packet(struct nf_conn *ct,
111 struct sk_buff *skb,
112 unsigned int dataoff,
113 enum ip_conntrack_info ctinfo,
114 const struct nf_hook_state *state);
115 int nf_conntrack_tcp_packet(struct nf_conn *ct,
116 struct sk_buff *skb,
117 unsigned int dataoff,
118 enum ip_conntrack_info ctinfo,
119 const struct nf_hook_state *state);
120 int nf_conntrack_dccp_packet(struct nf_conn *ct,
121 struct sk_buff *skb,
122 unsigned int dataoff,
123 enum ip_conntrack_info ctinfo,
124 const struct nf_hook_state *state);
125 int nf_conntrack_sctp_packet(struct nf_conn *ct,
126 struct sk_buff *skb,
127 unsigned int dataoff,
128 enum ip_conntrack_info ctinfo,
129 const struct nf_hook_state *state);
130 int nf_conntrack_gre_packet(struct nf_conn *ct,
131 struct sk_buff *skb,
132 unsigned int dataoff,
133 enum ip_conntrack_info ctinfo,
134 const struct nf_hook_state *state);
135
136 void nf_conntrack_generic_init_net(struct net *net);
137 void nf_conntrack_tcp_init_net(struct net *net);
138 void nf_conntrack_udp_init_net(struct net *net);
139 void nf_conntrack_gre_init_net(struct net *net);
140 void nf_conntrack_dccp_init_net(struct net *net);
141 void nf_conntrack_sctp_init_net(struct net *net);
142 void nf_conntrack_icmp_init_net(struct net *net);
143 void nf_conntrack_icmpv6_init_net(struct net *net);
144
145 /* Existing built-in generic protocol */
146 extern const struct nf_conntrack_l4proto nf_conntrack_l4proto_generic;
147
148 #define MAX_NF_CT_PROTO IPPROTO_UDPLITE
149
150 const struct nf_conntrack_l4proto *nf_ct_l4proto_find(u8 l4proto);
151
152 /* Generic netlink helpers */
153 int nf_ct_port_tuple_to_nlattr(struct sk_buff *skb,
154 const struct nf_conntrack_tuple *tuple);
155 int nf_ct_port_nlattr_to_tuple(struct nlattr *tb[],
156 struct nf_conntrack_tuple *t,
157 u_int32_t flags);
158 unsigned int nf_ct_port_nlattr_tuple_size(void);
159 extern const struct nla_policy nf_ct_port_nla_policy[];
160
161 #ifdef CONFIG_SYSCTL
162 __printf(4, 5) __cold
163 void nf_ct_l4proto_log_invalid(const struct sk_buff *skb,
164 const struct nf_conn *ct,
165 const struct nf_hook_state *state,
166 const char *fmt, ...);
167 __printf(4, 5) __cold
168 void nf_l4proto_log_invalid(const struct sk_buff *skb,
169 const struct nf_hook_state *state,
170 u8 protonum,
171 const char *fmt, ...);
172 #else
173 static inline __printf(4, 5) __cold
nf_l4proto_log_invalid(const struct sk_buff * skb,const struct nf_hook_state * state,u8 protonum,const char * fmt,...)174 void nf_l4proto_log_invalid(const struct sk_buff *skb,
175 const struct nf_hook_state *state,
176 u8 protonum,
177 const char *fmt, ...) {}
178 static inline __printf(4, 5) __cold
nf_ct_l4proto_log_invalid(const struct sk_buff * skb,const struct nf_conn * ct,const struct nf_hook_state * state,const char * fmt,...)179 void nf_ct_l4proto_log_invalid(const struct sk_buff *skb,
180 const struct nf_conn *ct,
181 const struct nf_hook_state *state,
182 const char *fmt, ...) { }
183 #endif /* CONFIG_SYSCTL */
184
185 #if IS_ENABLED(CONFIG_NF_CONNTRACK)
nf_generic_pernet(struct net * net)186 static inline struct nf_generic_net *nf_generic_pernet(struct net *net)
187 {
188 return &net->ct.nf_ct_proto.generic;
189 }
190
nf_tcp_pernet(struct net * net)191 static inline struct nf_tcp_net *nf_tcp_pernet(struct net *net)
192 {
193 return &net->ct.nf_ct_proto.tcp;
194 }
195
nf_udp_pernet(struct net * net)196 static inline struct nf_udp_net *nf_udp_pernet(struct net *net)
197 {
198 return &net->ct.nf_ct_proto.udp;
199 }
200
nf_icmp_pernet(struct net * net)201 static inline struct nf_icmp_net *nf_icmp_pernet(struct net *net)
202 {
203 return &net->ct.nf_ct_proto.icmp;
204 }
205
nf_icmpv6_pernet(struct net * net)206 static inline struct nf_icmp_net *nf_icmpv6_pernet(struct net *net)
207 {
208 return &net->ct.nf_ct_proto.icmpv6;
209 }
210
211 /* Caller must check nf_ct_protonum(ct) is IPPROTO_TCP before calling. */
nf_ct_set_tcp_be_liberal(struct nf_conn * ct)212 static inline void nf_ct_set_tcp_be_liberal(struct nf_conn *ct)
213 {
214 ct->proto.tcp.seen[0].flags |= IP_CT_TCP_FLAG_BE_LIBERAL;
215 ct->proto.tcp.seen[1].flags |= IP_CT_TCP_FLAG_BE_LIBERAL;
216 }
217
218 /* Caller must check nf_ct_protonum(ct) is IPPROTO_TCP before calling. */
nf_conntrack_tcp_established(const struct nf_conn * ct)219 static inline bool nf_conntrack_tcp_established(const struct nf_conn *ct)
220 {
221 return ct->proto.tcp.state == TCP_CONNTRACK_ESTABLISHED &&
222 test_bit(IPS_ASSURED_BIT, &ct->status);
223 }
224 #endif
225
226 #ifdef CONFIG_NF_CT_PROTO_DCCP
nf_dccp_pernet(struct net * net)227 static inline struct nf_dccp_net *nf_dccp_pernet(struct net *net)
228 {
229 return &net->ct.nf_ct_proto.dccp;
230 }
231 #endif
232
233 #ifdef CONFIG_NF_CT_PROTO_SCTP
nf_sctp_pernet(struct net * net)234 static inline struct nf_sctp_net *nf_sctp_pernet(struct net *net)
235 {
236 return &net->ct.nf_ct_proto.sctp;
237 }
238 #endif
239
240 #ifdef CONFIG_NF_CT_PROTO_GRE
nf_gre_pernet(struct net * net)241 static inline struct nf_gre_net *nf_gre_pernet(struct net *net)
242 {
243 return &net->ct.nf_ct_proto.gre;
244 }
245 #endif
246
247 #endif /*_NF_CONNTRACK_PROTOCOL_H*/
248