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
dissector_set_mpls_lse(struct flow_dissector_key_mpls * mpls,int lse_index)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 /**
305 * struct flow_dissector_key_ipsec:
306 * @spi: identifier for a ipsec connection
307 */
308 struct flow_dissector_key_ipsec {
309 __be32 spi;
310 };
311
312 /**
313 * struct flow_dissector_key_cfm
314 * @mdl_ver: maintenance domain level (mdl) and cfm protocol version
315 * @opcode: code specifying a type of cfm protocol packet
316 *
317 * See 802.1ag, ITU-T G.8013/Y.1731
318 * 1 2
319 * |7 6 5 4 3 2 1 0|7 6 5 4 3 2 1 0|
320 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
321 * | mdl | version | opcode |
322 * +-----+---------+-+-+-+-+-+-+-+-+
323 */
324 struct flow_dissector_key_cfm {
325 u8 mdl_ver;
326 u8 opcode;
327 };
328
329 #define FLOW_DIS_CFM_MDL_MASK GENMASK(7, 5)
330 #define FLOW_DIS_CFM_MDL_MAX 7
331
332 enum flow_dissector_key_id {
333 FLOW_DISSECTOR_KEY_CONTROL, /* struct flow_dissector_key_control */
334 FLOW_DISSECTOR_KEY_BASIC, /* struct flow_dissector_key_basic */
335 FLOW_DISSECTOR_KEY_IPV4_ADDRS, /* struct flow_dissector_key_ipv4_addrs */
336 FLOW_DISSECTOR_KEY_IPV6_ADDRS, /* struct flow_dissector_key_ipv6_addrs */
337 FLOW_DISSECTOR_KEY_PORTS, /* struct flow_dissector_key_ports */
338 FLOW_DISSECTOR_KEY_PORTS_RANGE, /* struct flow_dissector_key_ports */
339 FLOW_DISSECTOR_KEY_ICMP, /* struct flow_dissector_key_icmp */
340 FLOW_DISSECTOR_KEY_ETH_ADDRS, /* struct flow_dissector_key_eth_addrs */
341 FLOW_DISSECTOR_KEY_TIPC, /* struct flow_dissector_key_tipc */
342 FLOW_DISSECTOR_KEY_ARP, /* struct flow_dissector_key_arp */
343 FLOW_DISSECTOR_KEY_VLAN, /* struct flow_dissector_key_vlan */
344 FLOW_DISSECTOR_KEY_FLOW_LABEL, /* struct flow_dissector_key_tags */
345 FLOW_DISSECTOR_KEY_GRE_KEYID, /* struct flow_dissector_key_keyid */
346 FLOW_DISSECTOR_KEY_MPLS_ENTROPY, /* struct flow_dissector_key_keyid */
347 FLOW_DISSECTOR_KEY_ENC_KEYID, /* struct flow_dissector_key_keyid */
348 FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS, /* struct flow_dissector_key_ipv4_addrs */
349 FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS, /* struct flow_dissector_key_ipv6_addrs */
350 FLOW_DISSECTOR_KEY_ENC_CONTROL, /* struct flow_dissector_key_control */
351 FLOW_DISSECTOR_KEY_ENC_PORTS, /* struct flow_dissector_key_ports */
352 FLOW_DISSECTOR_KEY_MPLS, /* struct flow_dissector_key_mpls */
353 FLOW_DISSECTOR_KEY_TCP, /* struct flow_dissector_key_tcp */
354 FLOW_DISSECTOR_KEY_IP, /* struct flow_dissector_key_ip */
355 FLOW_DISSECTOR_KEY_CVLAN, /* struct flow_dissector_key_vlan */
356 FLOW_DISSECTOR_KEY_ENC_IP, /* struct flow_dissector_key_ip */
357 FLOW_DISSECTOR_KEY_ENC_OPTS, /* struct flow_dissector_key_enc_opts */
358 FLOW_DISSECTOR_KEY_META, /* struct flow_dissector_key_meta */
359 FLOW_DISSECTOR_KEY_CT, /* struct flow_dissector_key_ct */
360 FLOW_DISSECTOR_KEY_HASH, /* struct flow_dissector_key_hash */
361 FLOW_DISSECTOR_KEY_NUM_OF_VLANS, /* struct flow_dissector_key_num_of_vlans */
362 FLOW_DISSECTOR_KEY_PPPOE, /* struct flow_dissector_key_pppoe */
363 FLOW_DISSECTOR_KEY_L2TPV3, /* struct flow_dissector_key_l2tpv3 */
364 FLOW_DISSECTOR_KEY_CFM, /* struct flow_dissector_key_cfm */
365 FLOW_DISSECTOR_KEY_IPSEC, /* struct flow_dissector_key_ipsec */
366
367 FLOW_DISSECTOR_KEY_MAX,
368 };
369
370 #define FLOW_DISSECTOR_F_PARSE_1ST_FRAG BIT(0)
371 #define FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL BIT(1)
372 #define FLOW_DISSECTOR_F_STOP_AT_ENCAP BIT(2)
373 #define FLOW_DISSECTOR_F_STOP_BEFORE_ENCAP BIT(3)
374
375 struct flow_dissector_key {
376 enum flow_dissector_key_id key_id;
377 size_t offset; /* offset of struct flow_dissector_key_*
378 in target the struct */
379 };
380
381 struct flow_dissector {
382 unsigned long long used_keys;
383 /* each bit represents presence of one key id */
384 unsigned short int offset[FLOW_DISSECTOR_KEY_MAX];
385 };
386
387 struct flow_keys_basic {
388 struct flow_dissector_key_control control;
389 struct flow_dissector_key_basic basic;
390 };
391
392 struct flow_keys {
393 struct flow_dissector_key_control control;
394 #define FLOW_KEYS_HASH_START_FIELD basic
395 struct flow_dissector_key_basic basic __aligned(SIPHASH_ALIGNMENT);
396 struct flow_dissector_key_tags tags;
397 struct flow_dissector_key_vlan vlan;
398 struct flow_dissector_key_vlan cvlan;
399 struct flow_dissector_key_keyid keyid;
400 struct flow_dissector_key_ports ports;
401 struct flow_dissector_key_icmp icmp;
402 /* 'addrs' must be the last member */
403 struct flow_dissector_key_addrs addrs;
404 };
405
406 #define FLOW_KEYS_HASH_OFFSET \
407 offsetof(struct flow_keys, FLOW_KEYS_HASH_START_FIELD)
408
409 __be32 flow_get_u32_src(const struct flow_keys *flow);
410 __be32 flow_get_u32_dst(const struct flow_keys *flow);
411
412 extern struct flow_dissector flow_keys_dissector;
413 extern struct flow_dissector flow_keys_basic_dissector;
414
415 /* struct flow_keys_digest:
416 *
417 * This structure is used to hold a digest of the full flow keys. This is a
418 * larger "hash" of a flow to allow definitively matching specific flows where
419 * the 32 bit skb->hash is not large enough. The size is limited to 16 bytes so
420 * that it can be used in CB of skb (see sch_choke for an example).
421 */
422 #define FLOW_KEYS_DIGEST_LEN 16
423 struct flow_keys_digest {
424 u8 data[FLOW_KEYS_DIGEST_LEN];
425 };
426
427 void make_flow_keys_digest(struct flow_keys_digest *digest,
428 const struct flow_keys *flow);
429
flow_keys_have_l4(const struct flow_keys * keys)430 static inline bool flow_keys_have_l4(const struct flow_keys *keys)
431 {
432 return (keys->ports.ports || keys->tags.flow_label);
433 }
434
435 u32 flow_hash_from_keys(struct flow_keys *keys);
436 void skb_flow_get_icmp_tci(const struct sk_buff *skb,
437 struct flow_dissector_key_icmp *key_icmp,
438 const void *data, int thoff, int hlen);
439
dissector_uses_key(const struct flow_dissector * flow_dissector,enum flow_dissector_key_id key_id)440 static inline bool dissector_uses_key(const struct flow_dissector *flow_dissector,
441 enum flow_dissector_key_id key_id)
442 {
443 return flow_dissector->used_keys & (1ULL << key_id);
444 }
445
skb_flow_dissector_target(struct flow_dissector * flow_dissector,enum flow_dissector_key_id key_id,void * target_container)446 static inline void *skb_flow_dissector_target(struct flow_dissector *flow_dissector,
447 enum flow_dissector_key_id key_id,
448 void *target_container)
449 {
450 return ((char *)target_container) + flow_dissector->offset[key_id];
451 }
452
453 struct bpf_flow_dissector {
454 struct bpf_flow_keys *flow_keys;
455 const struct sk_buff *skb;
456 const void *data;
457 const void *data_end;
458 };
459
460 static inline void
flow_dissector_init_keys(struct flow_dissector_key_control * key_control,struct flow_dissector_key_basic * key_basic)461 flow_dissector_init_keys(struct flow_dissector_key_control *key_control,
462 struct flow_dissector_key_basic *key_basic)
463 {
464 memset(key_control, 0, sizeof(*key_control));
465 memset(key_basic, 0, sizeof(*key_basic));
466 }
467
468 #ifdef CONFIG_BPF_SYSCALL
469 int flow_dissector_bpf_prog_attach_check(struct net *net,
470 struct bpf_prog *prog);
471 #endif /* CONFIG_BPF_SYSCALL */
472
473 #endif
474