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 #include <uapi/linux/pkt_cls.h>
11
12 struct bpf_prog;
13 struct net;
14 struct sk_buff;
15
16 /**
17 * struct flow_dissector_key_control:
18 * @thoff: Transport header offset
19 * @addr_type: Type of key. One of FLOW_DISSECTOR_KEY_*
20 * @flags: Key flags.
21 * Any of FLOW_DIS_(IS_FRAGMENT|FIRST_FRAG|ENCAPSULATION|F_*)
22 */
23 struct flow_dissector_key_control {
24 u16 thoff;
25 u16 addr_type;
26 u32 flags;
27 };
28
29 /* The control flags are kept in sync with TCA_FLOWER_KEY_FLAGS_*, as those
30 * flags are exposed to userspace in some error paths, ie. unsupported flags.
31 */
32 enum flow_dissector_ctrl_flags {
33 FLOW_DIS_IS_FRAGMENT = TCA_FLOWER_KEY_FLAGS_IS_FRAGMENT,
34 FLOW_DIS_FIRST_FRAG = TCA_FLOWER_KEY_FLAGS_FRAG_IS_FIRST,
35 FLOW_DIS_F_TUNNEL_CSUM = TCA_FLOWER_KEY_FLAGS_TUNNEL_CSUM,
36 FLOW_DIS_F_TUNNEL_DONT_FRAGMENT = TCA_FLOWER_KEY_FLAGS_TUNNEL_DONT_FRAGMENT,
37 FLOW_DIS_F_TUNNEL_OAM = TCA_FLOWER_KEY_FLAGS_TUNNEL_OAM,
38 FLOW_DIS_F_TUNNEL_CRIT_OPT = TCA_FLOWER_KEY_FLAGS_TUNNEL_CRIT_OPT,
39
40 /* These flags are internal to the kernel */
41 FLOW_DIS_ENCAPSULATION = (TCA_FLOWER_KEY_FLAGS_MAX << 1),
42 };
43
44 enum flow_dissect_ret {
45 FLOW_DISSECT_RET_OUT_GOOD,
46 FLOW_DISSECT_RET_OUT_BAD,
47 FLOW_DISSECT_RET_PROTO_AGAIN,
48 FLOW_DISSECT_RET_IPPROTO_AGAIN,
49 FLOW_DISSECT_RET_CONTINUE,
50 };
51
52 /**
53 * struct flow_dissector_key_basic:
54 * @n_proto: Network header protocol (eg. IPv4/IPv6)
55 * @ip_proto: Transport header protocol (eg. TCP/UDP)
56 * @padding: Unused
57 */
58 struct flow_dissector_key_basic {
59 __be16 n_proto;
60 u8 ip_proto;
61 u8 padding;
62 };
63
64 struct flow_dissector_key_tags {
65 u32 flow_label;
66 };
67
68 struct flow_dissector_key_vlan {
69 union {
70 struct {
71 u16 vlan_id:12,
72 vlan_dei:1,
73 vlan_priority:3;
74 };
75 __be16 vlan_tci;
76 };
77 __be16 vlan_tpid;
78 __be16 vlan_eth_type;
79 u16 padding;
80 };
81
82 struct flow_dissector_mpls_lse {
83 u32 mpls_ttl:8,
84 mpls_bos:1,
85 mpls_tc:3,
86 mpls_label:20;
87 };
88
89 #define FLOW_DIS_MPLS_MAX 7
90 struct flow_dissector_key_mpls {
91 struct flow_dissector_mpls_lse ls[FLOW_DIS_MPLS_MAX]; /* Label Stack */
92 u8 used_lses; /* One bit set for each Label Stack Entry in use */
93 };
94
dissector_set_mpls_lse(struct flow_dissector_key_mpls * mpls,int lse_index)95 static inline void dissector_set_mpls_lse(struct flow_dissector_key_mpls *mpls,
96 int lse_index)
97 {
98 mpls->used_lses |= 1 << lse_index;
99 }
100
101 #define FLOW_DIS_TUN_OPTS_MAX 255
102 /**
103 * struct flow_dissector_key_enc_opts:
104 * @data: tunnel option data
105 * @len: length of tunnel option data
106 * @dst_opt_type: tunnel option type
107 */
108 struct flow_dissector_key_enc_opts {
109 u8 data[FLOW_DIS_TUN_OPTS_MAX]; /* Using IP_TUNNEL_OPTS_MAX is desired
110 * here but seems difficult to #include
111 */
112 u8 len;
113 u32 dst_opt_type;
114 };
115
116 struct flow_dissector_key_keyid {
117 __be32 keyid;
118 };
119
120 /**
121 * struct flow_dissector_key_ipv4_addrs:
122 * @src: source ip address
123 * @dst: destination ip address
124 */
125 struct flow_dissector_key_ipv4_addrs {
126 /* (src,dst) must be grouped, in the same way than in IP header */
127 __be32 src;
128 __be32 dst;
129 };
130
131 /**
132 * struct flow_dissector_key_ipv6_addrs:
133 * @src: source ip address
134 * @dst: destination ip address
135 */
136 struct flow_dissector_key_ipv6_addrs {
137 /* (src,dst) must be grouped, in the same way than in IP header */
138 struct in6_addr src;
139 struct in6_addr dst;
140 };
141
142 /**
143 * struct flow_dissector_key_tipc:
144 * @key: source node address combined with selector
145 */
146 struct flow_dissector_key_tipc {
147 __be32 key;
148 };
149
150 /**
151 * struct flow_dissector_key_addrs:
152 * @v4addrs: IPv4 addresses
153 * @v6addrs: IPv6 addresses
154 * @tipckey: TIPC key
155 */
156 struct flow_dissector_key_addrs {
157 union {
158 struct flow_dissector_key_ipv4_addrs v4addrs;
159 struct flow_dissector_key_ipv6_addrs v6addrs;
160 struct flow_dissector_key_tipc tipckey;
161 };
162 };
163
164 /**
165 * struct flow_dissector_key_arp:
166 * @sip: Sender IP address
167 * @tip: Target IP address
168 * @op: Operation
169 * @sha: Sender hardware address
170 * @tha: Target hardware address
171 */
172 struct flow_dissector_key_arp {
173 __u32 sip;
174 __u32 tip;
175 __u8 op;
176 unsigned char sha[ETH_ALEN];
177 unsigned char tha[ETH_ALEN];
178 };
179
180 /**
181 * struct flow_dissector_key_ports:
182 * @ports: port numbers of Transport header
183 * @src: source port number
184 * @dst: destination port number
185 */
186 struct flow_dissector_key_ports {
187 union {
188 __be32 ports;
189 struct {
190 __be16 src;
191 __be16 dst;
192 };
193 };
194 };
195
196 /**
197 * struct flow_dissector_key_ports_range
198 * @tp: port number from packet
199 * @tp_min: min port number in range
200 * @tp_max: max port number in range
201 */
202 struct flow_dissector_key_ports_range {
203 union {
204 struct flow_dissector_key_ports tp;
205 struct {
206 struct flow_dissector_key_ports tp_min;
207 struct flow_dissector_key_ports tp_max;
208 };
209 };
210 };
211
212 /**
213 * struct flow_dissector_key_icmp:
214 * @type: ICMP type
215 * @code: ICMP code
216 * @id: Session identifier
217 */
218 struct flow_dissector_key_icmp {
219 struct {
220 u8 type;
221 u8 code;
222 };
223 u16 id;
224 };
225
226 /**
227 * struct flow_dissector_key_eth_addrs:
228 * @src: source Ethernet address
229 * @dst: destination Ethernet address
230 */
231 struct flow_dissector_key_eth_addrs {
232 /* (dst,src) must be grouped, in the same way than in ETH header */
233 unsigned char dst[ETH_ALEN];
234 unsigned char src[ETH_ALEN];
235 };
236
237 /**
238 * struct flow_dissector_key_tcp:
239 * @flags: flags
240 */
241 struct flow_dissector_key_tcp {
242 __be16 flags;
243 };
244
245 /**
246 * struct flow_dissector_key_ip:
247 * @tos: tos
248 * @ttl: ttl
249 */
250 struct flow_dissector_key_ip {
251 __u8 tos;
252 __u8 ttl;
253 };
254
255 /**
256 * struct flow_dissector_key_meta:
257 * @ingress_ifindex: ingress ifindex
258 * @ingress_iftype: ingress interface type
259 * @l2_miss: packet did not match an L2 entry during forwarding
260 */
261 struct flow_dissector_key_meta {
262 int ingress_ifindex;
263 u16 ingress_iftype;
264 u8 l2_miss;
265 };
266
267 /**
268 * struct flow_dissector_key_ct:
269 * @ct_state: conntrack state after converting with map
270 * @ct_mark: conttrack mark
271 * @ct_zone: conntrack zone
272 * @ct_labels: conntrack labels
273 */
274 struct flow_dissector_key_ct {
275 u16 ct_state;
276 u16 ct_zone;
277 u32 ct_mark;
278 u32 ct_labels[4];
279 };
280
281 /**
282 * struct flow_dissector_key_hash:
283 * @hash: hash value
284 */
285 struct flow_dissector_key_hash {
286 u32 hash;
287 };
288
289 /**
290 * struct flow_dissector_key_num_of_vlans:
291 * @num_of_vlans: num_of_vlans value
292 */
293 struct flow_dissector_key_num_of_vlans {
294 u8 num_of_vlans;
295 };
296
297 /**
298 * struct flow_dissector_key_pppoe:
299 * @session_id: pppoe session id
300 * @ppp_proto: ppp protocol
301 * @type: pppoe eth type
302 */
303 struct flow_dissector_key_pppoe {
304 __be16 session_id;
305 __be16 ppp_proto;
306 __be16 type;
307 };
308
309 /**
310 * struct flow_dissector_key_l2tpv3:
311 * @session_id: identifier for a l2tp session
312 */
313 struct flow_dissector_key_l2tpv3 {
314 __be32 session_id;
315 };
316
317 /**
318 * struct flow_dissector_key_ipsec:
319 * @spi: identifier for a ipsec connection
320 */
321 struct flow_dissector_key_ipsec {
322 __be32 spi;
323 };
324
325 /**
326 * struct flow_dissector_key_cfm
327 * @mdl_ver: maintenance domain level (mdl) and cfm protocol version
328 * @opcode: code specifying a type of cfm protocol packet
329 *
330 * See 802.1ag, ITU-T G.8013/Y.1731
331 * 1 2
332 * |7 6 5 4 3 2 1 0|7 6 5 4 3 2 1 0|
333 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
334 * | mdl | version | opcode |
335 * +-----+---------+-+-+-+-+-+-+-+-+
336 */
337 struct flow_dissector_key_cfm {
338 u8 mdl_ver;
339 u8 opcode;
340 };
341
342 #define FLOW_DIS_CFM_MDL_MASK GENMASK(7, 5)
343 #define FLOW_DIS_CFM_MDL_MAX 7
344
345 enum flow_dissector_key_id {
346 FLOW_DISSECTOR_KEY_CONTROL, /* struct flow_dissector_key_control */
347 FLOW_DISSECTOR_KEY_BASIC, /* struct flow_dissector_key_basic */
348 FLOW_DISSECTOR_KEY_IPV4_ADDRS, /* struct flow_dissector_key_ipv4_addrs */
349 FLOW_DISSECTOR_KEY_IPV6_ADDRS, /* struct flow_dissector_key_ipv6_addrs */
350 FLOW_DISSECTOR_KEY_PORTS, /* struct flow_dissector_key_ports */
351 FLOW_DISSECTOR_KEY_PORTS_RANGE, /* struct flow_dissector_key_ports */
352 FLOW_DISSECTOR_KEY_ICMP, /* struct flow_dissector_key_icmp */
353 FLOW_DISSECTOR_KEY_ETH_ADDRS, /* struct flow_dissector_key_eth_addrs */
354 FLOW_DISSECTOR_KEY_TIPC, /* struct flow_dissector_key_tipc */
355 FLOW_DISSECTOR_KEY_ARP, /* struct flow_dissector_key_arp */
356 FLOW_DISSECTOR_KEY_VLAN, /* struct flow_dissector_key_vlan */
357 FLOW_DISSECTOR_KEY_FLOW_LABEL, /* struct flow_dissector_key_tags */
358 FLOW_DISSECTOR_KEY_GRE_KEYID, /* struct flow_dissector_key_keyid */
359 FLOW_DISSECTOR_KEY_MPLS_ENTROPY, /* struct flow_dissector_key_keyid */
360 FLOW_DISSECTOR_KEY_ENC_KEYID, /* struct flow_dissector_key_keyid */
361 FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS, /* struct flow_dissector_key_ipv4_addrs */
362 FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS, /* struct flow_dissector_key_ipv6_addrs */
363 FLOW_DISSECTOR_KEY_ENC_CONTROL, /* struct flow_dissector_key_control */
364 FLOW_DISSECTOR_KEY_ENC_PORTS, /* struct flow_dissector_key_ports */
365 FLOW_DISSECTOR_KEY_MPLS, /* struct flow_dissector_key_mpls */
366 FLOW_DISSECTOR_KEY_TCP, /* struct flow_dissector_key_tcp */
367 FLOW_DISSECTOR_KEY_IP, /* struct flow_dissector_key_ip */
368 FLOW_DISSECTOR_KEY_CVLAN, /* struct flow_dissector_key_vlan */
369 FLOW_DISSECTOR_KEY_ENC_IP, /* struct flow_dissector_key_ip */
370 FLOW_DISSECTOR_KEY_ENC_OPTS, /* struct flow_dissector_key_enc_opts */
371 FLOW_DISSECTOR_KEY_META, /* struct flow_dissector_key_meta */
372 FLOW_DISSECTOR_KEY_CT, /* struct flow_dissector_key_ct */
373 FLOW_DISSECTOR_KEY_HASH, /* struct flow_dissector_key_hash */
374 FLOW_DISSECTOR_KEY_NUM_OF_VLANS, /* struct flow_dissector_key_num_of_vlans */
375 FLOW_DISSECTOR_KEY_PPPOE, /* struct flow_dissector_key_pppoe */
376 FLOW_DISSECTOR_KEY_L2TPV3, /* struct flow_dissector_key_l2tpv3 */
377 FLOW_DISSECTOR_KEY_CFM, /* struct flow_dissector_key_cfm */
378 FLOW_DISSECTOR_KEY_IPSEC, /* struct flow_dissector_key_ipsec */
379
380 FLOW_DISSECTOR_KEY_MAX,
381 };
382
383 #define FLOW_DISSECTOR_F_PARSE_1ST_FRAG BIT(0)
384 #define FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL BIT(1)
385 #define FLOW_DISSECTOR_F_STOP_AT_ENCAP BIT(2)
386 #define FLOW_DISSECTOR_F_STOP_BEFORE_ENCAP BIT(3)
387
388 struct flow_dissector_key {
389 enum flow_dissector_key_id key_id;
390 size_t offset; /* offset of struct flow_dissector_key_*
391 in target the struct */
392 };
393
394 struct flow_dissector {
395 unsigned long long used_keys;
396 /* each bit represents presence of one key id */
397 unsigned short int offset[FLOW_DISSECTOR_KEY_MAX];
398 };
399
400 struct flow_keys_basic {
401 struct flow_dissector_key_control control;
402 struct flow_dissector_key_basic basic;
403 };
404
405 struct flow_keys {
406 struct flow_dissector_key_control control;
407 #define FLOW_KEYS_HASH_START_FIELD basic
408 struct flow_dissector_key_basic basic __aligned(SIPHASH_ALIGNMENT);
409 struct flow_dissector_key_tags tags;
410 struct flow_dissector_key_vlan vlan;
411 struct flow_dissector_key_vlan cvlan;
412 struct flow_dissector_key_keyid keyid;
413 struct flow_dissector_key_ports ports;
414 struct flow_dissector_key_icmp icmp;
415 /* 'addrs' must be the last member */
416 struct flow_dissector_key_addrs addrs;
417 };
418
419 #define FLOW_KEYS_HASH_OFFSET \
420 offsetof(struct flow_keys, FLOW_KEYS_HASH_START_FIELD)
421
422 __be32 flow_get_u32_src(const struct flow_keys *flow);
423 __be32 flow_get_u32_dst(const struct flow_keys *flow);
424
425 extern struct flow_dissector flow_keys_dissector;
426 extern struct flow_dissector flow_keys_basic_dissector;
427
428 /* struct flow_keys_digest:
429 *
430 * This structure is used to hold a digest of the full flow keys. This is a
431 * larger "hash" of a flow to allow definitively matching specific flows where
432 * the 32 bit skb->hash is not large enough. The size is limited to 16 bytes so
433 * that it can be used in CB of skb (see sch_choke for an example).
434 */
435 #define FLOW_KEYS_DIGEST_LEN 16
436 struct flow_keys_digest {
437 u8 data[FLOW_KEYS_DIGEST_LEN];
438 };
439
440 void make_flow_keys_digest(struct flow_keys_digest *digest,
441 const struct flow_keys *flow);
442
flow_keys_have_l4(const struct flow_keys * keys)443 static inline bool flow_keys_have_l4(const struct flow_keys *keys)
444 {
445 return (keys->ports.ports || keys->tags.flow_label);
446 }
447
448 u32 flow_hash_from_keys(struct flow_keys *keys);
449 u32 flow_hash_from_keys_seed(struct flow_keys *keys,
450 const siphash_key_t *keyval);
451 void skb_flow_get_icmp_tci(const struct sk_buff *skb,
452 struct flow_dissector_key_icmp *key_icmp,
453 const void *data, int thoff, int hlen);
454
dissector_uses_key(const struct flow_dissector * flow_dissector,enum flow_dissector_key_id key_id)455 static inline bool dissector_uses_key(const struct flow_dissector *flow_dissector,
456 enum flow_dissector_key_id key_id)
457 {
458 return flow_dissector->used_keys & (1ULL << key_id);
459 }
460
skb_flow_dissector_target(struct flow_dissector * flow_dissector,enum flow_dissector_key_id key_id,void * target_container)461 static inline void *skb_flow_dissector_target(struct flow_dissector *flow_dissector,
462 enum flow_dissector_key_id key_id,
463 void *target_container)
464 {
465 return ((char *)target_container) + flow_dissector->offset[key_id];
466 }
467
468 struct bpf_flow_dissector {
469 struct bpf_flow_keys *flow_keys;
470 const struct sk_buff *skb;
471 const void *data;
472 const void *data_end;
473 };
474
475 static inline void
flow_dissector_init_keys(struct flow_dissector_key_control * key_control,struct flow_dissector_key_basic * key_basic)476 flow_dissector_init_keys(struct flow_dissector_key_control *key_control,
477 struct flow_dissector_key_basic *key_basic)
478 {
479 memset(key_control, 0, sizeof(*key_control));
480 memset(key_basic, 0, sizeof(*key_basic));
481 }
482
483 #ifdef CONFIG_BPF_SYSCALL
484 int flow_dissector_bpf_prog_attach_check(struct net *net,
485 struct bpf_prog *prog);
486 #endif /* CONFIG_BPF_SYSCALL */
487
488 #endif
489