xref: /openbmc/linux/include/net/flow_dissector.h (revision 9a6b55ac)
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  * @thoff: Transport header offset
37  * @n_proto: Network header protocol (eg. IPv4/IPv6)
38  * @ip_proto: Transport header protocol (eg. TCP/UDP)
39  */
40 struct flow_dissector_key_basic {
41 	__be16	n_proto;
42 	u8	ip_proto;
43 	u8	padding;
44 };
45 
46 struct flow_dissector_key_tags {
47 	u32	flow_label;
48 };
49 
50 struct flow_dissector_key_vlan {
51 	union {
52 		struct {
53 			u16	vlan_id:12,
54 				vlan_dei:1,
55 				vlan_priority:3;
56 		};
57 		__be16	vlan_tci;
58 	};
59 	__be16	vlan_tpid;
60 };
61 
62 struct flow_dissector_key_mpls {
63 	u32	mpls_ttl:8,
64 		mpls_bos:1,
65 		mpls_tc:3,
66 		mpls_label:20;
67 };
68 
69 #define FLOW_DIS_TUN_OPTS_MAX 255
70 /**
71  * struct flow_dissector_key_enc_opts:
72  * @data: tunnel option data
73  * @len: length of tunnel option data
74  * @dst_opt_type: tunnel option type
75  */
76 struct flow_dissector_key_enc_opts {
77 	u8 data[FLOW_DIS_TUN_OPTS_MAX];	/* Using IP_TUNNEL_OPTS_MAX is desired
78 					 * here but seems difficult to #include
79 					 */
80 	u8 len;
81 	__be16 dst_opt_type;
82 };
83 
84 struct flow_dissector_key_keyid {
85 	__be32	keyid;
86 };
87 
88 /**
89  * struct flow_dissector_key_ipv4_addrs:
90  * @src: source ip address
91  * @dst: destination ip address
92  */
93 struct flow_dissector_key_ipv4_addrs {
94 	/* (src,dst) must be grouped, in the same way than in IP header */
95 	__be32 src;
96 	__be32 dst;
97 };
98 
99 /**
100  * struct flow_dissector_key_ipv6_addrs:
101  * @src: source ip address
102  * @dst: destination ip address
103  */
104 struct flow_dissector_key_ipv6_addrs {
105 	/* (src,dst) must be grouped, in the same way than in IP header */
106 	struct in6_addr src;
107 	struct in6_addr dst;
108 };
109 
110 /**
111  * struct flow_dissector_key_tipc:
112  * @key: source node address combined with selector
113  */
114 struct flow_dissector_key_tipc {
115 	__be32 key;
116 };
117 
118 /**
119  * struct flow_dissector_key_addrs:
120  * @v4addrs: IPv4 addresses
121  * @v6addrs: IPv6 addresses
122  */
123 struct flow_dissector_key_addrs {
124 	union {
125 		struct flow_dissector_key_ipv4_addrs v4addrs;
126 		struct flow_dissector_key_ipv6_addrs v6addrs;
127 		struct flow_dissector_key_tipc tipckey;
128 	};
129 };
130 
131 /**
132  * flow_dissector_key_arp:
133  *	@ports: Operation, source and target addresses for an ARP header
134  *              for Ethernet hardware addresses and IPv4 protocol addresses
135  *		sip: Sender IP address
136  *		tip: Target IP address
137  *		op:  Operation
138  *		sha: Sender hardware address
139  *		tpa: Target hardware address
140  */
141 struct flow_dissector_key_arp {
142 	__u32 sip;
143 	__u32 tip;
144 	__u8 op;
145 	unsigned char sha[ETH_ALEN];
146 	unsigned char tha[ETH_ALEN];
147 };
148 
149 /**
150  * flow_dissector_key_tp_ports:
151  *	@ports: port numbers of Transport header
152  *		src: source port number
153  *		dst: destination port number
154  */
155 struct flow_dissector_key_ports {
156 	union {
157 		__be32 ports;
158 		struct {
159 			__be16 src;
160 			__be16 dst;
161 		};
162 	};
163 };
164 
165 /**
166  * flow_dissector_key_icmp:
167  *		type: ICMP type
168  *		code: ICMP code
169  *		id:   session identifier
170  */
171 struct flow_dissector_key_icmp {
172 	struct {
173 		u8 type;
174 		u8 code;
175 	};
176 	u16 id;
177 };
178 
179 /**
180  * struct flow_dissector_key_eth_addrs:
181  * @src: source Ethernet address
182  * @dst: destination Ethernet address
183  */
184 struct flow_dissector_key_eth_addrs {
185 	/* (dst,src) must be grouped, in the same way than in ETH header */
186 	unsigned char dst[ETH_ALEN];
187 	unsigned char src[ETH_ALEN];
188 };
189 
190 /**
191  * struct flow_dissector_key_tcp:
192  * @flags: flags
193  */
194 struct flow_dissector_key_tcp {
195 	__be16 flags;
196 };
197 
198 /**
199  * struct flow_dissector_key_ip:
200  * @tos: tos
201  * @ttl: ttl
202  */
203 struct flow_dissector_key_ip {
204 	__u8	tos;
205 	__u8	ttl;
206 };
207 
208 /**
209  * struct flow_dissector_key_meta:
210  * @ingress_ifindex: ingress ifindex
211  * @ingress_iftype: ingress interface type
212  */
213 struct flow_dissector_key_meta {
214 	int ingress_ifindex;
215 	u16 ingress_iftype;
216 };
217 
218 /**
219  * struct flow_dissector_key_ct:
220  * @ct_state: conntrack state after converting with map
221  * @ct_mark: conttrack mark
222  * @ct_zone: conntrack zone
223  * @ct_labels: conntrack labels
224  */
225 struct flow_dissector_key_ct {
226 	u16	ct_state;
227 	u16	ct_zone;
228 	u32	ct_mark;
229 	u32	ct_labels[4];
230 };
231 
232 enum flow_dissector_key_id {
233 	FLOW_DISSECTOR_KEY_CONTROL, /* struct flow_dissector_key_control */
234 	FLOW_DISSECTOR_KEY_BASIC, /* struct flow_dissector_key_basic */
235 	FLOW_DISSECTOR_KEY_IPV4_ADDRS, /* struct flow_dissector_key_ipv4_addrs */
236 	FLOW_DISSECTOR_KEY_IPV6_ADDRS, /* struct flow_dissector_key_ipv6_addrs */
237 	FLOW_DISSECTOR_KEY_PORTS, /* struct flow_dissector_key_ports */
238 	FLOW_DISSECTOR_KEY_PORTS_RANGE, /* struct flow_dissector_key_ports */
239 	FLOW_DISSECTOR_KEY_ICMP, /* struct flow_dissector_key_icmp */
240 	FLOW_DISSECTOR_KEY_ETH_ADDRS, /* struct flow_dissector_key_eth_addrs */
241 	FLOW_DISSECTOR_KEY_TIPC, /* struct flow_dissector_key_tipc */
242 	FLOW_DISSECTOR_KEY_ARP, /* struct flow_dissector_key_arp */
243 	FLOW_DISSECTOR_KEY_VLAN, /* struct flow_dissector_key_vlan */
244 	FLOW_DISSECTOR_KEY_FLOW_LABEL, /* struct flow_dissector_key_tags */
245 	FLOW_DISSECTOR_KEY_GRE_KEYID, /* struct flow_dissector_key_keyid */
246 	FLOW_DISSECTOR_KEY_MPLS_ENTROPY, /* struct flow_dissector_key_keyid */
247 	FLOW_DISSECTOR_KEY_ENC_KEYID, /* struct flow_dissector_key_keyid */
248 	FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS, /* struct flow_dissector_key_ipv4_addrs */
249 	FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS, /* struct flow_dissector_key_ipv6_addrs */
250 	FLOW_DISSECTOR_KEY_ENC_CONTROL, /* struct flow_dissector_key_control */
251 	FLOW_DISSECTOR_KEY_ENC_PORTS, /* struct flow_dissector_key_ports */
252 	FLOW_DISSECTOR_KEY_MPLS, /* struct flow_dissector_key_mpls */
253 	FLOW_DISSECTOR_KEY_TCP, /* struct flow_dissector_key_tcp */
254 	FLOW_DISSECTOR_KEY_IP, /* struct flow_dissector_key_ip */
255 	FLOW_DISSECTOR_KEY_CVLAN, /* struct flow_dissector_key_vlan */
256 	FLOW_DISSECTOR_KEY_ENC_IP, /* struct flow_dissector_key_ip */
257 	FLOW_DISSECTOR_KEY_ENC_OPTS, /* struct flow_dissector_key_enc_opts */
258 	FLOW_DISSECTOR_KEY_META, /* struct flow_dissector_key_meta */
259 	FLOW_DISSECTOR_KEY_CT, /* struct flow_dissector_key_ct */
260 
261 	FLOW_DISSECTOR_KEY_MAX,
262 };
263 
264 #define FLOW_DISSECTOR_F_PARSE_1ST_FRAG		BIT(0)
265 #define FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL	BIT(1)
266 #define FLOW_DISSECTOR_F_STOP_AT_ENCAP		BIT(2)
267 
268 struct flow_dissector_key {
269 	enum flow_dissector_key_id key_id;
270 	size_t offset; /* offset of struct flow_dissector_key_*
271 			  in target the struct */
272 };
273 
274 struct flow_dissector {
275 	unsigned int used_keys; /* each bit repesents presence of one key id */
276 	unsigned short int offset[FLOW_DISSECTOR_KEY_MAX];
277 };
278 
279 struct flow_keys_basic {
280 	struct flow_dissector_key_control control;
281 	struct flow_dissector_key_basic basic;
282 };
283 
284 struct flow_keys {
285 	struct flow_dissector_key_control control;
286 #define FLOW_KEYS_HASH_START_FIELD basic
287 	struct flow_dissector_key_basic basic __aligned(SIPHASH_ALIGNMENT);
288 	struct flow_dissector_key_tags tags;
289 	struct flow_dissector_key_vlan vlan;
290 	struct flow_dissector_key_vlan cvlan;
291 	struct flow_dissector_key_keyid keyid;
292 	struct flow_dissector_key_ports ports;
293 	struct flow_dissector_key_icmp icmp;
294 	/* 'addrs' must be the last member */
295 	struct flow_dissector_key_addrs addrs;
296 };
297 
298 #define FLOW_KEYS_HASH_OFFSET		\
299 	offsetof(struct flow_keys, FLOW_KEYS_HASH_START_FIELD)
300 
301 __be32 flow_get_u32_src(const struct flow_keys *flow);
302 __be32 flow_get_u32_dst(const struct flow_keys *flow);
303 
304 extern struct flow_dissector flow_keys_dissector;
305 extern struct flow_dissector flow_keys_basic_dissector;
306 
307 /* struct flow_keys_digest:
308  *
309  * This structure is used to hold a digest of the full flow keys. This is a
310  * larger "hash" of a flow to allow definitively matching specific flows where
311  * the 32 bit skb->hash is not large enough. The size is limited to 16 bytes so
312  * that it can be used in CB of skb (see sch_choke for an example).
313  */
314 #define FLOW_KEYS_DIGEST_LEN	16
315 struct flow_keys_digest {
316 	u8	data[FLOW_KEYS_DIGEST_LEN];
317 };
318 
319 void make_flow_keys_digest(struct flow_keys_digest *digest,
320 			   const struct flow_keys *flow);
321 
322 static inline bool flow_keys_have_l4(const struct flow_keys *keys)
323 {
324 	return (keys->ports.ports || keys->tags.flow_label);
325 }
326 
327 u32 flow_hash_from_keys(struct flow_keys *keys);
328 void skb_flow_get_icmp_tci(const struct sk_buff *skb,
329 			   struct flow_dissector_key_icmp *key_icmp,
330 			   void *data, int thoff, int hlen);
331 
332 static inline bool dissector_uses_key(const struct flow_dissector *flow_dissector,
333 				      enum flow_dissector_key_id key_id)
334 {
335 	return flow_dissector->used_keys & (1 << key_id);
336 }
337 
338 static inline void *skb_flow_dissector_target(struct flow_dissector *flow_dissector,
339 					      enum flow_dissector_key_id key_id,
340 					      void *target_container)
341 {
342 	return ((char *)target_container) + flow_dissector->offset[key_id];
343 }
344 
345 struct bpf_flow_dissector {
346 	struct bpf_flow_keys	*flow_keys;
347 	const struct sk_buff	*skb;
348 	void			*data;
349 	void			*data_end;
350 };
351 
352 #endif
353