xref: /openbmc/linux/include/net/flow_dissector.h (revision a03a91bd68cb00c615e602cf605e6be12bedaa90)
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 struct bpf_prog;
12 struct net;
13 struct sk_buff;
14 
15 /**
16  * struct flow_dissector_key_control:
17  * @thoff:     Transport header offset
18  * @addr_type: Type of key. One of FLOW_DISSECTOR_KEY_*
19  * @flags:     Key flags. Any of FLOW_DIS_(IS_FRAGMENT|FIRST_FRAGENCAPSULATION)
20  */
21 struct flow_dissector_key_control {
22 	u16	thoff;
23 	u16	addr_type;
24 	u32	flags;
25 };
26 
27 #define FLOW_DIS_IS_FRAGMENT	BIT(0)
28 #define FLOW_DIS_FIRST_FRAG	BIT(1)
29 #define FLOW_DIS_ENCAPSULATION	BIT(2)
30 
31 enum flow_dissect_ret {
32 	FLOW_DISSECT_RET_OUT_GOOD,
33 	FLOW_DISSECT_RET_OUT_BAD,
34 	FLOW_DISSECT_RET_PROTO_AGAIN,
35 	FLOW_DISSECT_RET_IPPROTO_AGAIN,
36 	FLOW_DISSECT_RET_CONTINUE,
37 };
38 
39 /**
40  * struct flow_dissector_key_basic:
41  * @n_proto:  Network header protocol (eg. IPv4/IPv6)
42  * @ip_proto: Transport header protocol (eg. TCP/UDP)
43  * @padding:  Unused
44  */
45 struct flow_dissector_key_basic {
46 	__be16	n_proto;
47 	u8	ip_proto;
48 	u8	padding;
49 };
50 
51 struct flow_dissector_key_tags {
52 	u32	flow_label;
53 };
54 
55 struct flow_dissector_key_vlan {
56 	union {
57 		struct {
58 			u16	vlan_id:12,
59 				vlan_dei:1,
60 				vlan_priority:3;
61 		};
62 		__be16	vlan_tci;
63 	};
64 	__be16	vlan_tpid;
65 	__be16	vlan_eth_type;
66 	u16	padding;
67 };
68 
69 struct flow_dissector_mpls_lse {
70 	u32	mpls_ttl:8,
71 		mpls_bos:1,
72 		mpls_tc:3,
73 		mpls_label:20;
74 };
75 
76 #define FLOW_DIS_MPLS_MAX 7
77 struct flow_dissector_key_mpls {
78 	struct flow_dissector_mpls_lse ls[FLOW_DIS_MPLS_MAX]; /* Label Stack */
79 	u8 used_lses; /* One bit set for each Label Stack Entry in use */
80 };
81 
82 static inline void dissector_set_mpls_lse(struct flow_dissector_key_mpls *mpls,
83 					  int lse_index)
84 {
85 	mpls->used_lses |= 1 << lse_index;
86 }
87 
88 #define FLOW_DIS_TUN_OPTS_MAX 255
89 /**
90  * struct flow_dissector_key_enc_opts:
91  * @data: tunnel option data
92  * @len: length of tunnel option data
93  * @dst_opt_type: tunnel option type
94  */
95 struct flow_dissector_key_enc_opts {
96 	u8 data[FLOW_DIS_TUN_OPTS_MAX];	/* Using IP_TUNNEL_OPTS_MAX is desired
97 					 * here but seems difficult to #include
98 					 */
99 	u8 len;
100 	__be16 dst_opt_type;
101 };
102 
103 struct flow_dissector_key_keyid {
104 	__be32	keyid;
105 };
106 
107 /**
108  * struct flow_dissector_key_ipv4_addrs:
109  * @src: source ip address
110  * @dst: destination ip address
111  */
112 struct flow_dissector_key_ipv4_addrs {
113 	/* (src,dst) must be grouped, in the same way than in IP header */
114 	__be32 src;
115 	__be32 dst;
116 };
117 
118 /**
119  * struct flow_dissector_key_ipv6_addrs:
120  * @src: source ip address
121  * @dst: destination ip address
122  */
123 struct flow_dissector_key_ipv6_addrs {
124 	/* (src,dst) must be grouped, in the same way than in IP header */
125 	struct in6_addr src;
126 	struct in6_addr dst;
127 };
128 
129 /**
130  * struct flow_dissector_key_tipc:
131  * @key: source node address combined with selector
132  */
133 struct flow_dissector_key_tipc {
134 	__be32 key;
135 };
136 
137 /**
138  * struct flow_dissector_key_addrs:
139  * @v4addrs: IPv4 addresses
140  * @v6addrs: IPv6 addresses
141  * @tipckey: TIPC key
142  */
143 struct flow_dissector_key_addrs {
144 	union {
145 		struct flow_dissector_key_ipv4_addrs v4addrs;
146 		struct flow_dissector_key_ipv6_addrs v6addrs;
147 		struct flow_dissector_key_tipc tipckey;
148 	};
149 };
150 
151 /**
152  * struct flow_dissector_key_arp:
153  * @sip: Sender IP address
154  * @tip: Target IP address
155  * @op:  Operation
156  * @sha: Sender hardware address
157  * @tha: Target hardware address
158  */
159 struct flow_dissector_key_arp {
160 	__u32 sip;
161 	__u32 tip;
162 	__u8 op;
163 	unsigned char sha[ETH_ALEN];
164 	unsigned char tha[ETH_ALEN];
165 };
166 
167 /**
168  * struct flow_dissector_key_ports:
169  * @ports: port numbers of Transport header
170  * @src: source port number
171  * @dst: destination port number
172  */
173 struct flow_dissector_key_ports {
174 	union {
175 		__be32 ports;
176 		struct {
177 			__be16 src;
178 			__be16 dst;
179 		};
180 	};
181 };
182 
183 /**
184  * struct flow_dissector_key_ports_range
185  * @tp: port number from packet
186  * @tp_min: min port number in range
187  * @tp_max: max port number in range
188  */
189 struct flow_dissector_key_ports_range {
190 	union {
191 		struct flow_dissector_key_ports tp;
192 		struct {
193 			struct flow_dissector_key_ports tp_min;
194 			struct flow_dissector_key_ports tp_max;
195 		};
196 	};
197 };
198 
199 /**
200  * struct flow_dissector_key_icmp:
201  * @type: ICMP type
202  * @code: ICMP code
203  * @id:   Session identifier
204  */
205 struct flow_dissector_key_icmp {
206 	struct {
207 		u8 type;
208 		u8 code;
209 	};
210 	u16 id;
211 };
212 
213 /**
214  * struct flow_dissector_key_eth_addrs:
215  * @src: source Ethernet address
216  * @dst: destination Ethernet address
217  */
218 struct flow_dissector_key_eth_addrs {
219 	/* (dst,src) must be grouped, in the same way than in ETH header */
220 	unsigned char dst[ETH_ALEN];
221 	unsigned char src[ETH_ALEN];
222 };
223 
224 /**
225  * struct flow_dissector_key_tcp:
226  * @flags: flags
227  */
228 struct flow_dissector_key_tcp {
229 	__be16 flags;
230 };
231 
232 /**
233  * struct flow_dissector_key_ip:
234  * @tos: tos
235  * @ttl: ttl
236  */
237 struct flow_dissector_key_ip {
238 	__u8	tos;
239 	__u8	ttl;
240 };
241 
242 /**
243  * struct flow_dissector_key_meta:
244  * @ingress_ifindex: ingress ifindex
245  * @ingress_iftype: ingress interface type
246  * @l2_miss: packet did not match an L2 entry during forwarding
247  */
248 struct flow_dissector_key_meta {
249 	int ingress_ifindex;
250 	u16 ingress_iftype;
251 	u8 l2_miss;
252 };
253 
254 /**
255  * struct flow_dissector_key_ct:
256  * @ct_state: conntrack state after converting with map
257  * @ct_mark: conttrack mark
258  * @ct_zone: conntrack zone
259  * @ct_labels: conntrack labels
260  */
261 struct flow_dissector_key_ct {
262 	u16	ct_state;
263 	u16	ct_zone;
264 	u32	ct_mark;
265 	u32	ct_labels[4];
266 };
267 
268 /**
269  * struct flow_dissector_key_hash:
270  * @hash: hash value
271  */
272 struct flow_dissector_key_hash {
273 	u32 hash;
274 };
275 
276 /**
277  * struct flow_dissector_key_num_of_vlans:
278  * @num_of_vlans: num_of_vlans value
279  */
280 struct flow_dissector_key_num_of_vlans {
281 	u8 num_of_vlans;
282 };
283 
284 /**
285  * struct flow_dissector_key_pppoe:
286  * @session_id: pppoe session id
287  * @ppp_proto: ppp protocol
288  * @type: pppoe eth type
289  */
290 struct flow_dissector_key_pppoe {
291 	__be16 session_id;
292 	__be16 ppp_proto;
293 	__be16 type;
294 };
295 
296 /**
297  * struct flow_dissector_key_l2tpv3:
298  * @session_id: identifier for a l2tp session
299  */
300 struct flow_dissector_key_l2tpv3 {
301 	__be32 session_id;
302 };
303 
304 enum flow_dissector_key_id {
305 	FLOW_DISSECTOR_KEY_CONTROL, /* struct flow_dissector_key_control */
306 	FLOW_DISSECTOR_KEY_BASIC, /* struct flow_dissector_key_basic */
307 	FLOW_DISSECTOR_KEY_IPV4_ADDRS, /* struct flow_dissector_key_ipv4_addrs */
308 	FLOW_DISSECTOR_KEY_IPV6_ADDRS, /* struct flow_dissector_key_ipv6_addrs */
309 	FLOW_DISSECTOR_KEY_PORTS, /* struct flow_dissector_key_ports */
310 	FLOW_DISSECTOR_KEY_PORTS_RANGE, /* struct flow_dissector_key_ports */
311 	FLOW_DISSECTOR_KEY_ICMP, /* struct flow_dissector_key_icmp */
312 	FLOW_DISSECTOR_KEY_ETH_ADDRS, /* struct flow_dissector_key_eth_addrs */
313 	FLOW_DISSECTOR_KEY_TIPC, /* struct flow_dissector_key_tipc */
314 	FLOW_DISSECTOR_KEY_ARP, /* struct flow_dissector_key_arp */
315 	FLOW_DISSECTOR_KEY_VLAN, /* struct flow_dissector_key_vlan */
316 	FLOW_DISSECTOR_KEY_FLOW_LABEL, /* struct flow_dissector_key_tags */
317 	FLOW_DISSECTOR_KEY_GRE_KEYID, /* struct flow_dissector_key_keyid */
318 	FLOW_DISSECTOR_KEY_MPLS_ENTROPY, /* struct flow_dissector_key_keyid */
319 	FLOW_DISSECTOR_KEY_ENC_KEYID, /* struct flow_dissector_key_keyid */
320 	FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS, /* struct flow_dissector_key_ipv4_addrs */
321 	FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS, /* struct flow_dissector_key_ipv6_addrs */
322 	FLOW_DISSECTOR_KEY_ENC_CONTROL, /* struct flow_dissector_key_control */
323 	FLOW_DISSECTOR_KEY_ENC_PORTS, /* struct flow_dissector_key_ports */
324 	FLOW_DISSECTOR_KEY_MPLS, /* struct flow_dissector_key_mpls */
325 	FLOW_DISSECTOR_KEY_TCP, /* struct flow_dissector_key_tcp */
326 	FLOW_DISSECTOR_KEY_IP, /* struct flow_dissector_key_ip */
327 	FLOW_DISSECTOR_KEY_CVLAN, /* struct flow_dissector_key_vlan */
328 	FLOW_DISSECTOR_KEY_ENC_IP, /* struct flow_dissector_key_ip */
329 	FLOW_DISSECTOR_KEY_ENC_OPTS, /* struct flow_dissector_key_enc_opts */
330 	FLOW_DISSECTOR_KEY_META, /* struct flow_dissector_key_meta */
331 	FLOW_DISSECTOR_KEY_CT, /* struct flow_dissector_key_ct */
332 	FLOW_DISSECTOR_KEY_HASH, /* struct flow_dissector_key_hash */
333 	FLOW_DISSECTOR_KEY_NUM_OF_VLANS, /* struct flow_dissector_key_num_of_vlans */
334 	FLOW_DISSECTOR_KEY_PPPOE, /* struct flow_dissector_key_pppoe */
335 	FLOW_DISSECTOR_KEY_L2TPV3, /* struct flow_dissector_key_l2tpv3 */
336 
337 	FLOW_DISSECTOR_KEY_MAX,
338 };
339 
340 #define FLOW_DISSECTOR_F_PARSE_1ST_FRAG		BIT(0)
341 #define FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL	BIT(1)
342 #define FLOW_DISSECTOR_F_STOP_AT_ENCAP		BIT(2)
343 #define FLOW_DISSECTOR_F_STOP_BEFORE_ENCAP	BIT(3)
344 
345 struct flow_dissector_key {
346 	enum flow_dissector_key_id key_id;
347 	size_t offset; /* offset of struct flow_dissector_key_*
348 			  in target the struct */
349 };
350 
351 struct flow_dissector {
352 	unsigned int used_keys; /* each bit repesents presence of one key id */
353 	unsigned short int offset[FLOW_DISSECTOR_KEY_MAX];
354 };
355 
356 struct flow_keys_basic {
357 	struct flow_dissector_key_control control;
358 	struct flow_dissector_key_basic basic;
359 };
360 
361 struct flow_keys {
362 	struct flow_dissector_key_control control;
363 #define FLOW_KEYS_HASH_START_FIELD basic
364 	struct flow_dissector_key_basic basic __aligned(SIPHASH_ALIGNMENT);
365 	struct flow_dissector_key_tags tags;
366 	struct flow_dissector_key_vlan vlan;
367 	struct flow_dissector_key_vlan cvlan;
368 	struct flow_dissector_key_keyid keyid;
369 	struct flow_dissector_key_ports ports;
370 	struct flow_dissector_key_icmp icmp;
371 	/* 'addrs' must be the last member */
372 	struct flow_dissector_key_addrs addrs;
373 };
374 
375 #define FLOW_KEYS_HASH_OFFSET		\
376 	offsetof(struct flow_keys, FLOW_KEYS_HASH_START_FIELD)
377 
378 __be32 flow_get_u32_src(const struct flow_keys *flow);
379 __be32 flow_get_u32_dst(const struct flow_keys *flow);
380 
381 extern struct flow_dissector flow_keys_dissector;
382 extern struct flow_dissector flow_keys_basic_dissector;
383 
384 /* struct flow_keys_digest:
385  *
386  * This structure is used to hold a digest of the full flow keys. This is a
387  * larger "hash" of a flow to allow definitively matching specific flows where
388  * the 32 bit skb->hash is not large enough. The size is limited to 16 bytes so
389  * that it can be used in CB of skb (see sch_choke for an example).
390  */
391 #define FLOW_KEYS_DIGEST_LEN	16
392 struct flow_keys_digest {
393 	u8	data[FLOW_KEYS_DIGEST_LEN];
394 };
395 
396 void make_flow_keys_digest(struct flow_keys_digest *digest,
397 			   const struct flow_keys *flow);
398 
399 static inline bool flow_keys_have_l4(const struct flow_keys *keys)
400 {
401 	return (keys->ports.ports || keys->tags.flow_label);
402 }
403 
404 u32 flow_hash_from_keys(struct flow_keys *keys);
405 void skb_flow_get_icmp_tci(const struct sk_buff *skb,
406 			   struct flow_dissector_key_icmp *key_icmp,
407 			   const void *data, int thoff, int hlen);
408 
409 static inline bool dissector_uses_key(const struct flow_dissector *flow_dissector,
410 				      enum flow_dissector_key_id key_id)
411 {
412 	return flow_dissector->used_keys & (1 << key_id);
413 }
414 
415 static inline void *skb_flow_dissector_target(struct flow_dissector *flow_dissector,
416 					      enum flow_dissector_key_id key_id,
417 					      void *target_container)
418 {
419 	return ((char *)target_container) + flow_dissector->offset[key_id];
420 }
421 
422 struct bpf_flow_dissector {
423 	struct bpf_flow_keys	*flow_keys;
424 	const struct sk_buff	*skb;
425 	const void		*data;
426 	const void		*data_end;
427 };
428 
429 static inline void
430 flow_dissector_init_keys(struct flow_dissector_key_control *key_control,
431 			 struct flow_dissector_key_basic *key_basic)
432 {
433 	memset(key_control, 0, sizeof(*key_control));
434 	memset(key_basic, 0, sizeof(*key_basic));
435 }
436 
437 #ifdef CONFIG_BPF_SYSCALL
438 int flow_dissector_bpf_prog_attach_check(struct net *net,
439 					 struct bpf_prog *prog);
440 #endif /* CONFIG_BPF_SYSCALL */
441 
442 #endif
443