xref: /openbmc/linux/include/net/flow_dissector.h (revision ffcdf473)
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  */
247 struct flow_dissector_key_meta {
248 	int ingress_ifindex;
249 	u16 ingress_iftype;
250 };
251 
252 /**
253  * struct flow_dissector_key_ct:
254  * @ct_state: conntrack state after converting with map
255  * @ct_mark: conttrack mark
256  * @ct_zone: conntrack zone
257  * @ct_labels: conntrack labels
258  */
259 struct flow_dissector_key_ct {
260 	u16	ct_state;
261 	u16	ct_zone;
262 	u32	ct_mark;
263 	u32	ct_labels[4];
264 };
265 
266 /**
267  * struct flow_dissector_key_hash:
268  * @hash: hash value
269  */
270 struct flow_dissector_key_hash {
271 	u32 hash;
272 };
273 
274 /**
275  * struct flow_dissector_key_num_of_vlans:
276  * @num_of_vlans: num_of_vlans value
277  */
278 struct flow_dissector_key_num_of_vlans {
279 	u8 num_of_vlans;
280 };
281 
282 /**
283  * struct flow_dissector_key_pppoe:
284  * @session_id: pppoe session id
285  * @ppp_proto: ppp protocol
286  * @type: pppoe eth type
287  */
288 struct flow_dissector_key_pppoe {
289 	__be16 session_id;
290 	__be16 ppp_proto;
291 	__be16 type;
292 };
293 
294 /**
295  * struct flow_dissector_key_l2tpv3:
296  * @session_id: identifier for a l2tp session
297  */
298 struct flow_dissector_key_l2tpv3 {
299 	__be32 session_id;
300 };
301 
302 enum flow_dissector_key_id {
303 	FLOW_DISSECTOR_KEY_CONTROL, /* struct flow_dissector_key_control */
304 	FLOW_DISSECTOR_KEY_BASIC, /* struct flow_dissector_key_basic */
305 	FLOW_DISSECTOR_KEY_IPV4_ADDRS, /* struct flow_dissector_key_ipv4_addrs */
306 	FLOW_DISSECTOR_KEY_IPV6_ADDRS, /* struct flow_dissector_key_ipv6_addrs */
307 	FLOW_DISSECTOR_KEY_PORTS, /* struct flow_dissector_key_ports */
308 	FLOW_DISSECTOR_KEY_PORTS_RANGE, /* struct flow_dissector_key_ports */
309 	FLOW_DISSECTOR_KEY_ICMP, /* struct flow_dissector_key_icmp */
310 	FLOW_DISSECTOR_KEY_ETH_ADDRS, /* struct flow_dissector_key_eth_addrs */
311 	FLOW_DISSECTOR_KEY_TIPC, /* struct flow_dissector_key_tipc */
312 	FLOW_DISSECTOR_KEY_ARP, /* struct flow_dissector_key_arp */
313 	FLOW_DISSECTOR_KEY_VLAN, /* struct flow_dissector_key_vlan */
314 	FLOW_DISSECTOR_KEY_FLOW_LABEL, /* struct flow_dissector_key_tags */
315 	FLOW_DISSECTOR_KEY_GRE_KEYID, /* struct flow_dissector_key_keyid */
316 	FLOW_DISSECTOR_KEY_MPLS_ENTROPY, /* struct flow_dissector_key_keyid */
317 	FLOW_DISSECTOR_KEY_ENC_KEYID, /* struct flow_dissector_key_keyid */
318 	FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS, /* struct flow_dissector_key_ipv4_addrs */
319 	FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS, /* struct flow_dissector_key_ipv6_addrs */
320 	FLOW_DISSECTOR_KEY_ENC_CONTROL, /* struct flow_dissector_key_control */
321 	FLOW_DISSECTOR_KEY_ENC_PORTS, /* struct flow_dissector_key_ports */
322 	FLOW_DISSECTOR_KEY_MPLS, /* struct flow_dissector_key_mpls */
323 	FLOW_DISSECTOR_KEY_TCP, /* struct flow_dissector_key_tcp */
324 	FLOW_DISSECTOR_KEY_IP, /* struct flow_dissector_key_ip */
325 	FLOW_DISSECTOR_KEY_CVLAN, /* struct flow_dissector_key_vlan */
326 	FLOW_DISSECTOR_KEY_ENC_IP, /* struct flow_dissector_key_ip */
327 	FLOW_DISSECTOR_KEY_ENC_OPTS, /* struct flow_dissector_key_enc_opts */
328 	FLOW_DISSECTOR_KEY_META, /* struct flow_dissector_key_meta */
329 	FLOW_DISSECTOR_KEY_CT, /* struct flow_dissector_key_ct */
330 	FLOW_DISSECTOR_KEY_HASH, /* struct flow_dissector_key_hash */
331 	FLOW_DISSECTOR_KEY_NUM_OF_VLANS, /* struct flow_dissector_key_num_of_vlans */
332 	FLOW_DISSECTOR_KEY_PPPOE, /* struct flow_dissector_key_pppoe */
333 	FLOW_DISSECTOR_KEY_L2TPV3, /* struct flow_dissector_key_l2tpv3 */
334 
335 	FLOW_DISSECTOR_KEY_MAX,
336 };
337 
338 #define FLOW_DISSECTOR_F_PARSE_1ST_FRAG		BIT(0)
339 #define FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL	BIT(1)
340 #define FLOW_DISSECTOR_F_STOP_AT_ENCAP		BIT(2)
341 #define FLOW_DISSECTOR_F_STOP_BEFORE_ENCAP	BIT(3)
342 
343 struct flow_dissector_key {
344 	enum flow_dissector_key_id key_id;
345 	size_t offset; /* offset of struct flow_dissector_key_*
346 			  in target the struct */
347 };
348 
349 struct flow_dissector {
350 	unsigned int used_keys; /* each bit repesents presence of one key id */
351 	unsigned short int offset[FLOW_DISSECTOR_KEY_MAX];
352 };
353 
354 struct flow_keys_basic {
355 	struct flow_dissector_key_control control;
356 	struct flow_dissector_key_basic basic;
357 };
358 
359 struct flow_keys {
360 	struct flow_dissector_key_control control;
361 #define FLOW_KEYS_HASH_START_FIELD basic
362 	struct flow_dissector_key_basic basic __aligned(SIPHASH_ALIGNMENT);
363 	struct flow_dissector_key_tags tags;
364 	struct flow_dissector_key_vlan vlan;
365 	struct flow_dissector_key_vlan cvlan;
366 	struct flow_dissector_key_keyid keyid;
367 	struct flow_dissector_key_ports ports;
368 	struct flow_dissector_key_icmp icmp;
369 	/* 'addrs' must be the last member */
370 	struct flow_dissector_key_addrs addrs;
371 };
372 
373 #define FLOW_KEYS_HASH_OFFSET		\
374 	offsetof(struct flow_keys, FLOW_KEYS_HASH_START_FIELD)
375 
376 __be32 flow_get_u32_src(const struct flow_keys *flow);
377 __be32 flow_get_u32_dst(const struct flow_keys *flow);
378 
379 extern struct flow_dissector flow_keys_dissector;
380 extern struct flow_dissector flow_keys_basic_dissector;
381 
382 /* struct flow_keys_digest:
383  *
384  * This structure is used to hold a digest of the full flow keys. This is a
385  * larger "hash" of a flow to allow definitively matching specific flows where
386  * the 32 bit skb->hash is not large enough. The size is limited to 16 bytes so
387  * that it can be used in CB of skb (see sch_choke for an example).
388  */
389 #define FLOW_KEYS_DIGEST_LEN	16
390 struct flow_keys_digest {
391 	u8	data[FLOW_KEYS_DIGEST_LEN];
392 };
393 
394 void make_flow_keys_digest(struct flow_keys_digest *digest,
395 			   const struct flow_keys *flow);
396 
397 static inline bool flow_keys_have_l4(const struct flow_keys *keys)
398 {
399 	return (keys->ports.ports || keys->tags.flow_label);
400 }
401 
402 u32 flow_hash_from_keys(struct flow_keys *keys);
403 void skb_flow_get_icmp_tci(const struct sk_buff *skb,
404 			   struct flow_dissector_key_icmp *key_icmp,
405 			   const void *data, int thoff, int hlen);
406 
407 static inline bool dissector_uses_key(const struct flow_dissector *flow_dissector,
408 				      enum flow_dissector_key_id key_id)
409 {
410 	return flow_dissector->used_keys & (1 << key_id);
411 }
412 
413 static inline void *skb_flow_dissector_target(struct flow_dissector *flow_dissector,
414 					      enum flow_dissector_key_id key_id,
415 					      void *target_container)
416 {
417 	return ((char *)target_container) + flow_dissector->offset[key_id];
418 }
419 
420 struct bpf_flow_dissector {
421 	struct bpf_flow_keys	*flow_keys;
422 	const struct sk_buff	*skb;
423 	const void		*data;
424 	const void		*data_end;
425 };
426 
427 static inline void
428 flow_dissector_init_keys(struct flow_dissector_key_control *key_control,
429 			 struct flow_dissector_key_basic *key_basic)
430 {
431 	memset(key_control, 0, sizeof(*key_control));
432 	memset(key_basic, 0, sizeof(*key_basic));
433 }
434 
435 #ifdef CONFIG_BPF_SYSCALL
436 int flow_dissector_bpf_prog_attach_check(struct net *net,
437 					 struct bpf_prog *prog);
438 #endif /* CONFIG_BPF_SYSCALL */
439 
440 #endif
441