xref: /openbmc/linux/include/net/flow_dissector.h (revision 87fcfa7b7fe6bf819033fe827a27f710e38639b5)
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 <uapi/linux/if_ether.h>
9 
10 struct sk_buff;
11 
12 /**
13  * struct flow_dissector_key_control:
14  * @thoff: Transport header offset
15  */
16 struct flow_dissector_key_control {
17 	u16	thoff;
18 	u16	addr_type;
19 	u32	flags;
20 };
21 
22 #define FLOW_DIS_IS_FRAGMENT	BIT(0)
23 #define FLOW_DIS_FIRST_FRAG	BIT(1)
24 #define FLOW_DIS_ENCAPSULATION	BIT(2)
25 
26 enum flow_dissect_ret {
27 	FLOW_DISSECT_RET_OUT_GOOD,
28 	FLOW_DISSECT_RET_OUT_BAD,
29 	FLOW_DISSECT_RET_PROTO_AGAIN,
30 	FLOW_DISSECT_RET_IPPROTO_AGAIN,
31 	FLOW_DISSECT_RET_CONTINUE,
32 };
33 
34 /**
35  * struct flow_dissector_key_basic:
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 	union {
51 		struct {
52 			u16	vlan_id:12,
53 				vlan_dei:1,
54 				vlan_priority:3;
55 		};
56 		__be16	vlan_tci;
57 	};
58 	__be16	vlan_tpid;
59 };
60 
61 struct flow_dissector_key_mpls {
62 	u32	mpls_ttl:8,
63 		mpls_bos:1,
64 		mpls_tc:3,
65 		mpls_label:20;
66 };
67 
68 #define FLOW_DIS_TUN_OPTS_MAX 255
69 /**
70  * struct flow_dissector_key_enc_opts:
71  * @data: tunnel option data
72  * @len: length of tunnel option data
73  * @dst_opt_type: tunnel option type
74  */
75 struct flow_dissector_key_enc_opts {
76 	u8 data[FLOW_DIS_TUN_OPTS_MAX];	/* Using IP_TUNNEL_OPTS_MAX is desired
77 					 * here but seems difficult to #include
78 					 */
79 	u8 len;
80 	__be16 dst_opt_type;
81 };
82 
83 struct flow_dissector_key_keyid {
84 	__be32	keyid;
85 };
86 
87 /**
88  * struct flow_dissector_key_ipv4_addrs:
89  * @src: source ip address
90  * @dst: destination ip address
91  */
92 struct flow_dissector_key_ipv4_addrs {
93 	/* (src,dst) must be grouped, in the same way than in IP header */
94 	__be32 src;
95 	__be32 dst;
96 };
97 
98 /**
99  * struct flow_dissector_key_ipv6_addrs:
100  * @src: source ip address
101  * @dst: destination ip address
102  */
103 struct flow_dissector_key_ipv6_addrs {
104 	/* (src,dst) must be grouped, in the same way than in IP header */
105 	struct in6_addr src;
106 	struct in6_addr dst;
107 };
108 
109 /**
110  * struct flow_dissector_key_tipc:
111  * @key: source node address combined with selector
112  */
113 struct flow_dissector_key_tipc {
114 	__be32 key;
115 };
116 
117 /**
118  * struct flow_dissector_key_addrs:
119  * @v4addrs: IPv4 addresses
120  * @v6addrs: IPv6 addresses
121  */
122 struct flow_dissector_key_addrs {
123 	union {
124 		struct flow_dissector_key_ipv4_addrs v4addrs;
125 		struct flow_dissector_key_ipv6_addrs v6addrs;
126 		struct flow_dissector_key_tipc tipckey;
127 	};
128 };
129 
130 /**
131  * flow_dissector_key_arp:
132  *	@ports: Operation, source and target addresses for an ARP header
133  *              for Ethernet hardware addresses and IPv4 protocol addresses
134  *		sip: Sender IP address
135  *		tip: Target IP address
136  *		op:  Operation
137  *		sha: Sender hardware address
138  *		tpa: Target hardware address
139  */
140 struct flow_dissector_key_arp {
141 	__u32 sip;
142 	__u32 tip;
143 	__u8 op;
144 	unsigned char sha[ETH_ALEN];
145 	unsigned char tha[ETH_ALEN];
146 };
147 
148 /**
149  * flow_dissector_key_tp_ports:
150  *	@ports: port numbers of Transport header
151  *		src: source port number
152  *		dst: destination port number
153  */
154 struct flow_dissector_key_ports {
155 	union {
156 		__be32 ports;
157 		struct {
158 			__be16 src;
159 			__be16 dst;
160 		};
161 	};
162 };
163 
164 /**
165  * flow_dissector_key_icmp:
166  *		type: ICMP type
167  *		code: ICMP code
168  *		id:   session identifier
169  */
170 struct flow_dissector_key_icmp {
171 	struct {
172 		u8 type;
173 		u8 code;
174 	};
175 	u16 id;
176 };
177 
178 /**
179  * struct flow_dissector_key_eth_addrs:
180  * @src: source Ethernet address
181  * @dst: destination Ethernet address
182  */
183 struct flow_dissector_key_eth_addrs {
184 	/* (dst,src) must be grouped, in the same way than in ETH header */
185 	unsigned char dst[ETH_ALEN];
186 	unsigned char src[ETH_ALEN];
187 };
188 
189 /**
190  * struct flow_dissector_key_tcp:
191  * @flags: flags
192  */
193 struct flow_dissector_key_tcp {
194 	__be16 flags;
195 };
196 
197 /**
198  * struct flow_dissector_key_ip:
199  * @tos: tos
200  * @ttl: ttl
201  */
202 struct flow_dissector_key_ip {
203 	__u8	tos;
204 	__u8	ttl;
205 };
206 
207 /**
208  * struct flow_dissector_key_meta:
209  * @ingress_ifindex: ingress ifindex
210  * @ingress_iftype: ingress interface type
211  */
212 struct flow_dissector_key_meta {
213 	int ingress_ifindex;
214 	u16 ingress_iftype;
215 };
216 
217 /**
218  * struct flow_dissector_key_ct:
219  * @ct_state: conntrack state after converting with map
220  * @ct_mark: conttrack mark
221  * @ct_zone: conntrack zone
222  * @ct_labels: conntrack labels
223  */
224 struct flow_dissector_key_ct {
225 	u16	ct_state;
226 	u16	ct_zone;
227 	u32	ct_mark;
228 	u32	ct_labels[4];
229 };
230 
231 enum flow_dissector_key_id {
232 	FLOW_DISSECTOR_KEY_CONTROL, /* struct flow_dissector_key_control */
233 	FLOW_DISSECTOR_KEY_BASIC, /* struct flow_dissector_key_basic */
234 	FLOW_DISSECTOR_KEY_IPV4_ADDRS, /* struct flow_dissector_key_ipv4_addrs */
235 	FLOW_DISSECTOR_KEY_IPV6_ADDRS, /* struct flow_dissector_key_ipv6_addrs */
236 	FLOW_DISSECTOR_KEY_PORTS, /* struct flow_dissector_key_ports */
237 	FLOW_DISSECTOR_KEY_PORTS_RANGE, /* struct flow_dissector_key_ports */
238 	FLOW_DISSECTOR_KEY_ICMP, /* struct flow_dissector_key_icmp */
239 	FLOW_DISSECTOR_KEY_ETH_ADDRS, /* struct flow_dissector_key_eth_addrs */
240 	FLOW_DISSECTOR_KEY_TIPC, /* struct flow_dissector_key_tipc */
241 	FLOW_DISSECTOR_KEY_ARP, /* struct flow_dissector_key_arp */
242 	FLOW_DISSECTOR_KEY_VLAN, /* struct flow_dissector_key_vlan */
243 	FLOW_DISSECTOR_KEY_FLOW_LABEL, /* struct flow_dissector_key_tags */
244 	FLOW_DISSECTOR_KEY_GRE_KEYID, /* struct flow_dissector_key_keyid */
245 	FLOW_DISSECTOR_KEY_MPLS_ENTROPY, /* struct flow_dissector_key_keyid */
246 	FLOW_DISSECTOR_KEY_ENC_KEYID, /* struct flow_dissector_key_keyid */
247 	FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS, /* struct flow_dissector_key_ipv4_addrs */
248 	FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS, /* struct flow_dissector_key_ipv6_addrs */
249 	FLOW_DISSECTOR_KEY_ENC_CONTROL, /* struct flow_dissector_key_control */
250 	FLOW_DISSECTOR_KEY_ENC_PORTS, /* struct flow_dissector_key_ports */
251 	FLOW_DISSECTOR_KEY_MPLS, /* struct flow_dissector_key_mpls */
252 	FLOW_DISSECTOR_KEY_TCP, /* struct flow_dissector_key_tcp */
253 	FLOW_DISSECTOR_KEY_IP, /* struct flow_dissector_key_ip */
254 	FLOW_DISSECTOR_KEY_CVLAN, /* struct flow_dissector_key_vlan */
255 	FLOW_DISSECTOR_KEY_ENC_IP, /* struct flow_dissector_key_ip */
256 	FLOW_DISSECTOR_KEY_ENC_OPTS, /* struct flow_dissector_key_enc_opts */
257 	FLOW_DISSECTOR_KEY_META, /* struct flow_dissector_key_meta */
258 	FLOW_DISSECTOR_KEY_CT, /* struct flow_dissector_key_ct */
259 
260 	FLOW_DISSECTOR_KEY_MAX,
261 };
262 
263 #define FLOW_DISSECTOR_F_PARSE_1ST_FRAG		BIT(0)
264 #define FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL	BIT(1)
265 #define FLOW_DISSECTOR_F_STOP_AT_ENCAP		BIT(2)
266 
267 struct flow_dissector_key {
268 	enum flow_dissector_key_id key_id;
269 	size_t offset; /* offset of struct flow_dissector_key_*
270 			  in target the struct */
271 };
272 
273 struct flow_dissector {
274 	unsigned int used_keys; /* each bit repesents presence of one key id */
275 	unsigned short int offset[FLOW_DISSECTOR_KEY_MAX];
276 };
277 
278 struct flow_keys_basic {
279 	struct flow_dissector_key_control control;
280 	struct flow_dissector_key_basic basic;
281 };
282 
283 struct flow_keys {
284 	struct flow_dissector_key_control control;
285 #define FLOW_KEYS_HASH_START_FIELD basic
286 	struct flow_dissector_key_basic basic __aligned(SIPHASH_ALIGNMENT);
287 	struct flow_dissector_key_tags tags;
288 	struct flow_dissector_key_vlan vlan;
289 	struct flow_dissector_key_vlan cvlan;
290 	struct flow_dissector_key_keyid keyid;
291 	struct flow_dissector_key_ports ports;
292 	struct flow_dissector_key_icmp icmp;
293 	/* 'addrs' must be the last member */
294 	struct flow_dissector_key_addrs addrs;
295 };
296 
297 #define FLOW_KEYS_HASH_OFFSET		\
298 	offsetof(struct flow_keys, FLOW_KEYS_HASH_START_FIELD)
299 
300 __be32 flow_get_u32_src(const struct flow_keys *flow);
301 __be32 flow_get_u32_dst(const struct flow_keys *flow);
302 
303 extern struct flow_dissector flow_keys_dissector;
304 extern struct flow_dissector flow_keys_basic_dissector;
305 
306 /* struct flow_keys_digest:
307  *
308  * This structure is used to hold a digest of the full flow keys. This is a
309  * larger "hash" of a flow to allow definitively matching specific flows where
310  * the 32 bit skb->hash is not large enough. The size is limited to 16 bytes so
311  * that it can be used in CB of skb (see sch_choke for an example).
312  */
313 #define FLOW_KEYS_DIGEST_LEN	16
314 struct flow_keys_digest {
315 	u8	data[FLOW_KEYS_DIGEST_LEN];
316 };
317 
318 void make_flow_keys_digest(struct flow_keys_digest *digest,
319 			   const struct flow_keys *flow);
320 
321 static inline bool flow_keys_have_l4(const struct flow_keys *keys)
322 {
323 	return (keys->ports.ports || keys->tags.flow_label);
324 }
325 
326 u32 flow_hash_from_keys(struct flow_keys *keys);
327 void skb_flow_get_icmp_tci(const struct sk_buff *skb,
328 			   struct flow_dissector_key_icmp *key_icmp,
329 			   void *data, int thoff, int hlen);
330 
331 static inline bool dissector_uses_key(const struct flow_dissector *flow_dissector,
332 				      enum flow_dissector_key_id key_id)
333 {
334 	return flow_dissector->used_keys & (1 << key_id);
335 }
336 
337 static inline void *skb_flow_dissector_target(struct flow_dissector *flow_dissector,
338 					      enum flow_dissector_key_id key_id,
339 					      void *target_container)
340 {
341 	return ((char *)target_container) + flow_dissector->offset[key_id];
342 }
343 
344 struct bpf_flow_dissector {
345 	struct bpf_flow_keys	*flow_keys;
346 	const struct sk_buff	*skb;
347 	void			*data;
348 	void			*data_end;
349 };
350 
351 #endif
352