xref: /openbmc/linux/include/net/flow_dissector.h (revision 65844828)
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  */
19 struct flow_dissector_key_control {
20 	u16	thoff;
21 	u16	addr_type;
22 	u32	flags;
23 };
24 
25 #define FLOW_DIS_IS_FRAGMENT	BIT(0)
26 #define FLOW_DIS_FIRST_FRAG	BIT(1)
27 #define FLOW_DIS_ENCAPSULATION	BIT(2)
28 
29 enum flow_dissect_ret {
30 	FLOW_DISSECT_RET_OUT_GOOD,
31 	FLOW_DISSECT_RET_OUT_BAD,
32 	FLOW_DISSECT_RET_PROTO_AGAIN,
33 	FLOW_DISSECT_RET_IPPROTO_AGAIN,
34 	FLOW_DISSECT_RET_CONTINUE,
35 };
36 
37 /**
38  * struct flow_dissector_key_basic:
39  * @n_proto: Network header protocol (eg. IPv4/IPv6)
40  * @ip_proto: Transport header protocol (eg. TCP/UDP)
41  */
42 struct flow_dissector_key_basic {
43 	__be16	n_proto;
44 	u8	ip_proto;
45 	u8	padding;
46 };
47 
48 struct flow_dissector_key_tags {
49 	u32	flow_label;
50 };
51 
52 struct flow_dissector_key_vlan {
53 	union {
54 		struct {
55 			u16	vlan_id:12,
56 				vlan_dei:1,
57 				vlan_priority:3;
58 		};
59 		__be16	vlan_tci;
60 	};
61 	__be16	vlan_tpid;
62 	__be16	vlan_eth_type;
63 	u16	padding;
64 };
65 
66 struct flow_dissector_mpls_lse {
67 	u32	mpls_ttl:8,
68 		mpls_bos:1,
69 		mpls_tc:3,
70 		mpls_label:20;
71 };
72 
73 #define FLOW_DIS_MPLS_MAX 7
74 struct flow_dissector_key_mpls {
75 	struct flow_dissector_mpls_lse ls[FLOW_DIS_MPLS_MAX]; /* Label Stack */
76 	u8 used_lses; /* One bit set for each Label Stack Entry in use */
77 };
78 
79 static inline void dissector_set_mpls_lse(struct flow_dissector_key_mpls *mpls,
80 					  int lse_index)
81 {
82 	mpls->used_lses |= 1 << lse_index;
83 }
84 
85 #define FLOW_DIS_TUN_OPTS_MAX 255
86 /**
87  * struct flow_dissector_key_enc_opts:
88  * @data: tunnel option data
89  * @len: length of tunnel option data
90  * @dst_opt_type: tunnel option type
91  */
92 struct flow_dissector_key_enc_opts {
93 	u8 data[FLOW_DIS_TUN_OPTS_MAX];	/* Using IP_TUNNEL_OPTS_MAX is desired
94 					 * here but seems difficult to #include
95 					 */
96 	u8 len;
97 	__be16 dst_opt_type;
98 };
99 
100 struct flow_dissector_key_keyid {
101 	__be32	keyid;
102 };
103 
104 /**
105  * struct flow_dissector_key_ipv4_addrs:
106  * @src: source ip address
107  * @dst: destination ip address
108  */
109 struct flow_dissector_key_ipv4_addrs {
110 	/* (src,dst) must be grouped, in the same way than in IP header */
111 	__be32 src;
112 	__be32 dst;
113 };
114 
115 /**
116  * struct flow_dissector_key_ipv6_addrs:
117  * @src: source ip address
118  * @dst: destination ip address
119  */
120 struct flow_dissector_key_ipv6_addrs {
121 	/* (src,dst) must be grouped, in the same way than in IP header */
122 	struct in6_addr src;
123 	struct in6_addr dst;
124 };
125 
126 /**
127  * struct flow_dissector_key_tipc:
128  * @key: source node address combined with selector
129  */
130 struct flow_dissector_key_tipc {
131 	__be32 key;
132 };
133 
134 /**
135  * struct flow_dissector_key_addrs:
136  * @v4addrs: IPv4 addresses
137  * @v6addrs: IPv6 addresses
138  */
139 struct flow_dissector_key_addrs {
140 	union {
141 		struct flow_dissector_key_ipv4_addrs v4addrs;
142 		struct flow_dissector_key_ipv6_addrs v6addrs;
143 		struct flow_dissector_key_tipc tipckey;
144 	};
145 };
146 
147 /**
148  * flow_dissector_key_arp:
149  *	@ports: Operation, source and target addresses for an ARP header
150  *              for Ethernet hardware addresses and IPv4 protocol addresses
151  *		sip: Sender IP address
152  *		tip: Target IP address
153  *		op:  Operation
154  *		sha: Sender hardware address
155  *		tpa: Target hardware address
156  */
157 struct flow_dissector_key_arp {
158 	__u32 sip;
159 	__u32 tip;
160 	__u8 op;
161 	unsigned char sha[ETH_ALEN];
162 	unsigned char tha[ETH_ALEN];
163 };
164 
165 /**
166  * flow_dissector_key_tp_ports:
167  *	@ports: port numbers of Transport header
168  *		src: source port number
169  *		dst: destination port number
170  */
171 struct flow_dissector_key_ports {
172 	union {
173 		__be32 ports;
174 		struct {
175 			__be16 src;
176 			__be16 dst;
177 		};
178 	};
179 };
180 
181 /**
182  * struct flow_dissector_key_ports_range
183  * @tp: port number from packet
184  * @tp_min: min port number in range
185  * @tp_max: max port number in range
186  */
187 struct flow_dissector_key_ports_range {
188 	union {
189 		struct flow_dissector_key_ports tp;
190 		struct {
191 			struct flow_dissector_key_ports tp_min;
192 			struct flow_dissector_key_ports tp_max;
193 		};
194 	};
195 };
196 
197 /**
198  * flow_dissector_key_icmp:
199  *		type: ICMP type
200  *		code: ICMP code
201  *		id:   session identifier
202  */
203 struct flow_dissector_key_icmp {
204 	struct {
205 		u8 type;
206 		u8 code;
207 	};
208 	u16 id;
209 };
210 
211 /**
212  * struct flow_dissector_key_eth_addrs:
213  * @src: source Ethernet address
214  * @dst: destination Ethernet address
215  */
216 struct flow_dissector_key_eth_addrs {
217 	/* (dst,src) must be grouped, in the same way than in ETH header */
218 	unsigned char dst[ETH_ALEN];
219 	unsigned char src[ETH_ALEN];
220 };
221 
222 /**
223  * struct flow_dissector_key_tcp:
224  * @flags: flags
225  */
226 struct flow_dissector_key_tcp {
227 	__be16 flags;
228 };
229 
230 /**
231  * struct flow_dissector_key_ip:
232  * @tos: tos
233  * @ttl: ttl
234  */
235 struct flow_dissector_key_ip {
236 	__u8	tos;
237 	__u8	ttl;
238 };
239 
240 /**
241  * struct flow_dissector_key_meta:
242  * @ingress_ifindex: ingress ifindex
243  * @ingress_iftype: ingress interface type
244  */
245 struct flow_dissector_key_meta {
246 	int ingress_ifindex;
247 	u16 ingress_iftype;
248 };
249 
250 /**
251  * struct flow_dissector_key_ct:
252  * @ct_state: conntrack state after converting with map
253  * @ct_mark: conttrack mark
254  * @ct_zone: conntrack zone
255  * @ct_labels: conntrack labels
256  */
257 struct flow_dissector_key_ct {
258 	u16	ct_state;
259 	u16	ct_zone;
260 	u32	ct_mark;
261 	u32	ct_labels[4];
262 };
263 
264 /**
265  * struct flow_dissector_key_hash:
266  * @hash: hash value
267  */
268 struct flow_dissector_key_hash {
269 	u32 hash;
270 };
271 
272 /**
273  * struct flow_dissector_key_num_of_vlans:
274  * @num_of_vlans: num_of_vlans value
275  */
276 struct flow_dissector_key_num_of_vlans {
277 	u8 num_of_vlans;
278 };
279 
280 /**
281  * struct flow_dissector_key_pppoe:
282  * @session_id: pppoe session id
283  * @ppp_proto: ppp protocol
284  * @type: pppoe eth type
285  */
286 struct flow_dissector_key_pppoe {
287 	__be16 session_id;
288 	__be16 ppp_proto;
289 	__be16 type;
290 };
291 
292 /**
293  * struct flow_dissector_key_l2tpv3:
294  * @session_id: identifier for a l2tp session
295  */
296 struct flow_dissector_key_l2tpv3 {
297 	__be32 session_id;
298 };
299 
300 enum flow_dissector_key_id {
301 	FLOW_DISSECTOR_KEY_CONTROL, /* struct flow_dissector_key_control */
302 	FLOW_DISSECTOR_KEY_BASIC, /* struct flow_dissector_key_basic */
303 	FLOW_DISSECTOR_KEY_IPV4_ADDRS, /* struct flow_dissector_key_ipv4_addrs */
304 	FLOW_DISSECTOR_KEY_IPV6_ADDRS, /* struct flow_dissector_key_ipv6_addrs */
305 	FLOW_DISSECTOR_KEY_PORTS, /* struct flow_dissector_key_ports */
306 	FLOW_DISSECTOR_KEY_PORTS_RANGE, /* struct flow_dissector_key_ports */
307 	FLOW_DISSECTOR_KEY_ICMP, /* struct flow_dissector_key_icmp */
308 	FLOW_DISSECTOR_KEY_ETH_ADDRS, /* struct flow_dissector_key_eth_addrs */
309 	FLOW_DISSECTOR_KEY_TIPC, /* struct flow_dissector_key_tipc */
310 	FLOW_DISSECTOR_KEY_ARP, /* struct flow_dissector_key_arp */
311 	FLOW_DISSECTOR_KEY_VLAN, /* struct flow_dissector_key_vlan */
312 	FLOW_DISSECTOR_KEY_FLOW_LABEL, /* struct flow_dissector_key_tags */
313 	FLOW_DISSECTOR_KEY_GRE_KEYID, /* struct flow_dissector_key_keyid */
314 	FLOW_DISSECTOR_KEY_MPLS_ENTROPY, /* struct flow_dissector_key_keyid */
315 	FLOW_DISSECTOR_KEY_ENC_KEYID, /* struct flow_dissector_key_keyid */
316 	FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS, /* struct flow_dissector_key_ipv4_addrs */
317 	FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS, /* struct flow_dissector_key_ipv6_addrs */
318 	FLOW_DISSECTOR_KEY_ENC_CONTROL, /* struct flow_dissector_key_control */
319 	FLOW_DISSECTOR_KEY_ENC_PORTS, /* struct flow_dissector_key_ports */
320 	FLOW_DISSECTOR_KEY_MPLS, /* struct flow_dissector_key_mpls */
321 	FLOW_DISSECTOR_KEY_TCP, /* struct flow_dissector_key_tcp */
322 	FLOW_DISSECTOR_KEY_IP, /* struct flow_dissector_key_ip */
323 	FLOW_DISSECTOR_KEY_CVLAN, /* struct flow_dissector_key_vlan */
324 	FLOW_DISSECTOR_KEY_ENC_IP, /* struct flow_dissector_key_ip */
325 	FLOW_DISSECTOR_KEY_ENC_OPTS, /* struct flow_dissector_key_enc_opts */
326 	FLOW_DISSECTOR_KEY_META, /* struct flow_dissector_key_meta */
327 	FLOW_DISSECTOR_KEY_CT, /* struct flow_dissector_key_ct */
328 	FLOW_DISSECTOR_KEY_HASH, /* struct flow_dissector_key_hash */
329 	FLOW_DISSECTOR_KEY_NUM_OF_VLANS, /* struct flow_dissector_key_num_of_vlans */
330 	FLOW_DISSECTOR_KEY_PPPOE, /* struct flow_dissector_key_pppoe */
331 	FLOW_DISSECTOR_KEY_L2TPV3, /* struct flow_dissector_key_l2tpv3 */
332 
333 	FLOW_DISSECTOR_KEY_MAX,
334 };
335 
336 #define FLOW_DISSECTOR_F_PARSE_1ST_FRAG		BIT(0)
337 #define FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL	BIT(1)
338 #define FLOW_DISSECTOR_F_STOP_AT_ENCAP		BIT(2)
339 #define FLOW_DISSECTOR_F_STOP_BEFORE_ENCAP	BIT(3)
340 
341 struct flow_dissector_key {
342 	enum flow_dissector_key_id key_id;
343 	size_t offset; /* offset of struct flow_dissector_key_*
344 			  in target the struct */
345 };
346 
347 struct flow_dissector {
348 	unsigned int used_keys; /* each bit repesents presence of one key id */
349 	unsigned short int offset[FLOW_DISSECTOR_KEY_MAX];
350 };
351 
352 struct flow_keys_basic {
353 	struct flow_dissector_key_control control;
354 	struct flow_dissector_key_basic basic;
355 };
356 
357 struct flow_keys {
358 	struct flow_dissector_key_control control;
359 #define FLOW_KEYS_HASH_START_FIELD basic
360 	struct flow_dissector_key_basic basic __aligned(SIPHASH_ALIGNMENT);
361 	struct flow_dissector_key_tags tags;
362 	struct flow_dissector_key_vlan vlan;
363 	struct flow_dissector_key_vlan cvlan;
364 	struct flow_dissector_key_keyid keyid;
365 	struct flow_dissector_key_ports ports;
366 	struct flow_dissector_key_icmp icmp;
367 	/* 'addrs' must be the last member */
368 	struct flow_dissector_key_addrs addrs;
369 };
370 
371 #define FLOW_KEYS_HASH_OFFSET		\
372 	offsetof(struct flow_keys, FLOW_KEYS_HASH_START_FIELD)
373 
374 __be32 flow_get_u32_src(const struct flow_keys *flow);
375 __be32 flow_get_u32_dst(const struct flow_keys *flow);
376 
377 extern struct flow_dissector flow_keys_dissector;
378 extern struct flow_dissector flow_keys_basic_dissector;
379 
380 /* struct flow_keys_digest:
381  *
382  * This structure is used to hold a digest of the full flow keys. This is a
383  * larger "hash" of a flow to allow definitively matching specific flows where
384  * the 32 bit skb->hash is not large enough. The size is limited to 16 bytes so
385  * that it can be used in CB of skb (see sch_choke for an example).
386  */
387 #define FLOW_KEYS_DIGEST_LEN	16
388 struct flow_keys_digest {
389 	u8	data[FLOW_KEYS_DIGEST_LEN];
390 };
391 
392 void make_flow_keys_digest(struct flow_keys_digest *digest,
393 			   const struct flow_keys *flow);
394 
395 static inline bool flow_keys_have_l4(const struct flow_keys *keys)
396 {
397 	return (keys->ports.ports || keys->tags.flow_label);
398 }
399 
400 u32 flow_hash_from_keys(struct flow_keys *keys);
401 void skb_flow_get_icmp_tci(const struct sk_buff *skb,
402 			   struct flow_dissector_key_icmp *key_icmp,
403 			   const void *data, int thoff, int hlen);
404 
405 static inline bool dissector_uses_key(const struct flow_dissector *flow_dissector,
406 				      enum flow_dissector_key_id key_id)
407 {
408 	return flow_dissector->used_keys & (1 << key_id);
409 }
410 
411 static inline void *skb_flow_dissector_target(struct flow_dissector *flow_dissector,
412 					      enum flow_dissector_key_id key_id,
413 					      void *target_container)
414 {
415 	return ((char *)target_container) + flow_dissector->offset[key_id];
416 }
417 
418 struct bpf_flow_dissector {
419 	struct bpf_flow_keys	*flow_keys;
420 	const struct sk_buff	*skb;
421 	const void		*data;
422 	const void		*data_end;
423 };
424 
425 static inline void
426 flow_dissector_init_keys(struct flow_dissector_key_control *key_control,
427 			 struct flow_dissector_key_basic *key_basic)
428 {
429 	memset(key_control, 0, sizeof(*key_control));
430 	memset(key_basic, 0, sizeof(*key_basic));
431 }
432 
433 #ifdef CONFIG_BPF_SYSCALL
434 int flow_dissector_bpf_prog_attach_check(struct net *net,
435 					 struct bpf_prog *prog);
436 #endif /* CONFIG_BPF_SYSCALL */
437 
438 #endif
439