1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _NET_FLOW_DISSECTOR_H
3 #define _NET_FLOW_DISSECTOR_H
4
5 #include <linux/types.h>
6 #include <linux/in6.h>
7 #include <linux/siphash.h>
8 #include <linux/string.h>
9 #include <uapi/linux/if_ether.h>
10
11 /**
12 * struct flow_dissector_key_control:
13 * @thoff: Transport header offset
14 */
15 struct flow_dissector_key_control {
16 u16 thoff;
17 u16 addr_type;
18 u32 flags;
19 };
20
21 #define FLOW_DIS_IS_FRAGMENT BIT(0)
22 #define FLOW_DIS_FIRST_FRAG BIT(1)
23 #define FLOW_DIS_ENCAPSULATION BIT(2)
24
25 enum flow_dissect_ret {
26 FLOW_DISSECT_RET_OUT_GOOD,
27 FLOW_DISSECT_RET_OUT_BAD,
28 FLOW_DISSECT_RET_PROTO_AGAIN,
29 FLOW_DISSECT_RET_IPPROTO_AGAIN,
30 FLOW_DISSECT_RET_CONTINUE,
31 };
32
33 /**
34 * struct flow_dissector_key_basic:
35 * @thoff: Transport header offset
36 * @n_proto: Network header protocol (eg. IPv4/IPv6)
37 * @ip_proto: Transport header protocol (eg. TCP/UDP)
38 */
39 struct flow_dissector_key_basic {
40 __be16 n_proto;
41 u8 ip_proto;
42 u8 padding;
43 };
44
45 struct flow_dissector_key_tags {
46 u32 flow_label;
47 };
48
49 struct flow_dissector_key_vlan {
50 u16 vlan_id:12,
51 vlan_priority:3;
52 __be16 vlan_tpid;
53 __be16 vlan_eth_type;
54 u16 padding;
55 };
56
57 struct flow_dissector_key_mpls {
58 u32 mpls_ttl:8,
59 mpls_bos:1,
60 mpls_tc:3,
61 mpls_label:20;
62 };
63
64 #define FLOW_DIS_TUN_OPTS_MAX 255
65 /**
66 * struct flow_dissector_key_enc_opts:
67 * @data: tunnel option data
68 * @len: length of tunnel option data
69 * @dst_opt_type: tunnel option type
70 */
71 struct flow_dissector_key_enc_opts {
72 u8 data[FLOW_DIS_TUN_OPTS_MAX]; /* Using IP_TUNNEL_OPTS_MAX is desired
73 * here but seems difficult to #include
74 */
75 u8 len;
76 __be16 dst_opt_type;
77 };
78
79 struct flow_dissector_key_keyid {
80 __be32 keyid;
81 };
82
83 /**
84 * struct flow_dissector_key_ipv4_addrs:
85 * @src: source ip address
86 * @dst: destination ip address
87 */
88 struct flow_dissector_key_ipv4_addrs {
89 /* (src,dst) must be grouped, in the same way than in IP header */
90 __be32 src;
91 __be32 dst;
92 };
93
94 /**
95 * struct flow_dissector_key_ipv6_addrs:
96 * @src: source ip address
97 * @dst: destination ip address
98 */
99 struct flow_dissector_key_ipv6_addrs {
100 /* (src,dst) must be grouped, in the same way than in IP header */
101 struct in6_addr src;
102 struct in6_addr dst;
103 };
104
105 /**
106 * struct flow_dissector_key_tipc:
107 * @key: source node address combined with selector
108 */
109 struct flow_dissector_key_tipc {
110 __be32 key;
111 };
112
113 /**
114 * struct flow_dissector_key_addrs:
115 * @v4addrs: IPv4 addresses
116 * @v6addrs: IPv6 addresses
117 */
118 struct flow_dissector_key_addrs {
119 union {
120 struct flow_dissector_key_ipv4_addrs v4addrs;
121 struct flow_dissector_key_ipv6_addrs v6addrs;
122 struct flow_dissector_key_tipc tipckey;
123 };
124 };
125
126 /**
127 * flow_dissector_key_arp:
128 * @ports: Operation, source and target addresses for an ARP header
129 * for Ethernet hardware addresses and IPv4 protocol addresses
130 * sip: Sender IP address
131 * tip: Target IP address
132 * op: Operation
133 * sha: Sender hardware address
134 * tpa: Target hardware address
135 */
136 struct flow_dissector_key_arp {
137 __u32 sip;
138 __u32 tip;
139 __u8 op;
140 unsigned char sha[ETH_ALEN];
141 unsigned char tha[ETH_ALEN];
142 };
143
144 /**
145 * flow_dissector_key_tp_ports:
146 * @ports: port numbers of Transport header
147 * src: source port number
148 * dst: destination port number
149 */
150 struct flow_dissector_key_ports {
151 union {
152 __be32 ports;
153 struct {
154 __be16 src;
155 __be16 dst;
156 };
157 };
158 };
159
160 /**
161 * flow_dissector_key_icmp:
162 * @ports: type and code of ICMP header
163 * icmp: ICMP type (high) and code (low)
164 * type: ICMP type
165 * code: ICMP code
166 */
167 struct flow_dissector_key_icmp {
168 union {
169 __be16 icmp;
170 struct {
171 u8 type;
172 u8 code;
173 };
174 };
175 };
176
177 /**
178 * struct flow_dissector_key_eth_addrs:
179 * @src: source Ethernet address
180 * @dst: destination Ethernet address
181 */
182 struct flow_dissector_key_eth_addrs {
183 /* (dst,src) must be grouped, in the same way than in ETH header */
184 unsigned char dst[ETH_ALEN];
185 unsigned char src[ETH_ALEN];
186 };
187
188 /**
189 * struct flow_dissector_key_tcp:
190 * @flags: flags
191 */
192 struct flow_dissector_key_tcp {
193 __be16 flags;
194 };
195
196 /**
197 * struct flow_dissector_key_ip:
198 * @tos: tos
199 * @ttl: ttl
200 */
201 struct flow_dissector_key_ip {
202 __u8 tos;
203 __u8 ttl;
204 };
205
206 enum flow_dissector_key_id {
207 FLOW_DISSECTOR_KEY_CONTROL, /* struct flow_dissector_key_control */
208 FLOW_DISSECTOR_KEY_BASIC, /* struct flow_dissector_key_basic */
209 FLOW_DISSECTOR_KEY_IPV4_ADDRS, /* struct flow_dissector_key_ipv4_addrs */
210 FLOW_DISSECTOR_KEY_IPV6_ADDRS, /* struct flow_dissector_key_ipv6_addrs */
211 FLOW_DISSECTOR_KEY_PORTS, /* struct flow_dissector_key_ports */
212 FLOW_DISSECTOR_KEY_ICMP, /* struct flow_dissector_key_icmp */
213 FLOW_DISSECTOR_KEY_ETH_ADDRS, /* struct flow_dissector_key_eth_addrs */
214 FLOW_DISSECTOR_KEY_TIPC, /* struct flow_dissector_key_tipc */
215 FLOW_DISSECTOR_KEY_ARP, /* struct flow_dissector_key_arp */
216 FLOW_DISSECTOR_KEY_VLAN, /* struct flow_dissector_key_flow_vlan */
217 FLOW_DISSECTOR_KEY_FLOW_LABEL, /* struct flow_dissector_key_flow_tags */
218 FLOW_DISSECTOR_KEY_GRE_KEYID, /* struct flow_dissector_key_keyid */
219 FLOW_DISSECTOR_KEY_MPLS_ENTROPY, /* struct flow_dissector_key_keyid */
220 FLOW_DISSECTOR_KEY_ENC_KEYID, /* struct flow_dissector_key_keyid */
221 FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS, /* struct flow_dissector_key_ipv4_addrs */
222 FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS, /* struct flow_dissector_key_ipv6_addrs */
223 FLOW_DISSECTOR_KEY_ENC_CONTROL, /* struct flow_dissector_key_control */
224 FLOW_DISSECTOR_KEY_ENC_PORTS, /* struct flow_dissector_key_ports */
225 FLOW_DISSECTOR_KEY_MPLS, /* struct flow_dissector_key_mpls */
226 FLOW_DISSECTOR_KEY_TCP, /* struct flow_dissector_key_tcp */
227 FLOW_DISSECTOR_KEY_IP, /* struct flow_dissector_key_ip */
228 FLOW_DISSECTOR_KEY_CVLAN, /* struct flow_dissector_key_flow_vlan */
229 FLOW_DISSECTOR_KEY_ENC_IP, /* struct flow_dissector_key_ip */
230 FLOW_DISSECTOR_KEY_ENC_OPTS, /* struct flow_dissector_key_enc_opts */
231
232 FLOW_DISSECTOR_KEY_MAX,
233 };
234
235 #define FLOW_DISSECTOR_F_PARSE_1ST_FRAG BIT(0)
236 #define FLOW_DISSECTOR_F_STOP_AT_L3 BIT(1)
237 #define FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL BIT(2)
238 #define FLOW_DISSECTOR_F_STOP_AT_ENCAP BIT(3)
239
240 struct flow_dissector_key {
241 enum flow_dissector_key_id key_id;
242 size_t offset; /* offset of struct flow_dissector_key_*
243 in target the struct */
244 };
245
246 struct flow_dissector {
247 unsigned int used_keys; /* each bit repesents presence of one key id */
248 unsigned short int offset[FLOW_DISSECTOR_KEY_MAX];
249 };
250
251 struct flow_keys_basic {
252 struct flow_dissector_key_control control;
253 struct flow_dissector_key_basic basic;
254 };
255
256 struct flow_keys {
257 struct flow_dissector_key_control control;
258 #define FLOW_KEYS_HASH_START_FIELD basic
259 struct flow_dissector_key_basic basic __aligned(SIPHASH_ALIGNMENT);
260 struct flow_dissector_key_tags tags;
261 struct flow_dissector_key_vlan vlan;
262 struct flow_dissector_key_vlan cvlan;
263 struct flow_dissector_key_keyid keyid;
264 struct flow_dissector_key_ports ports;
265 struct flow_dissector_key_addrs addrs;
266 };
267
268 #define FLOW_KEYS_HASH_OFFSET \
269 offsetof(struct flow_keys, FLOW_KEYS_HASH_START_FIELD)
270
271 __be32 flow_get_u32_src(const struct flow_keys *flow);
272 __be32 flow_get_u32_dst(const struct flow_keys *flow);
273
274 extern struct flow_dissector flow_keys_dissector;
275 extern struct flow_dissector flow_keys_basic_dissector;
276
277 /* struct flow_keys_digest:
278 *
279 * This structure is used to hold a digest of the full flow keys. This is a
280 * larger "hash" of a flow to allow definitively matching specific flows where
281 * the 32 bit skb->hash is not large enough. The size is limited to 16 bytes so
282 * that it can be used in CB of skb (see sch_choke for an example).
283 */
284 #define FLOW_KEYS_DIGEST_LEN 16
285 struct flow_keys_digest {
286 u8 data[FLOW_KEYS_DIGEST_LEN];
287 };
288
289 void make_flow_keys_digest(struct flow_keys_digest *digest,
290 const struct flow_keys *flow);
291
flow_keys_have_l4(const struct flow_keys * keys)292 static inline bool flow_keys_have_l4(const struct flow_keys *keys)
293 {
294 return (keys->ports.ports || keys->tags.flow_label);
295 }
296
297 u32 flow_hash_from_keys(struct flow_keys *keys);
298
dissector_uses_key(const struct flow_dissector * flow_dissector,enum flow_dissector_key_id key_id)299 static inline bool dissector_uses_key(const struct flow_dissector *flow_dissector,
300 enum flow_dissector_key_id key_id)
301 {
302 return flow_dissector->used_keys & (1 << key_id);
303 }
304
skb_flow_dissector_target(struct flow_dissector * flow_dissector,enum flow_dissector_key_id key_id,void * target_container)305 static inline void *skb_flow_dissector_target(struct flow_dissector *flow_dissector,
306 enum flow_dissector_key_id key_id,
307 void *target_container)
308 {
309 return ((char *)target_container) + flow_dissector->offset[key_id];
310 }
311
312 static inline void
flow_dissector_init_keys(struct flow_dissector_key_control * key_control,struct flow_dissector_key_basic * key_basic)313 flow_dissector_init_keys(struct flow_dissector_key_control *key_control,
314 struct flow_dissector_key_basic *key_basic)
315 {
316 memset(key_control, 0, sizeof(*key_control));
317 memset(key_basic, 0, sizeof(*key_basic));
318 }
319
320 #endif
321