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
dissector_set_mpls_lse(struct flow_dissector_key_mpls * mpls,int lse_index)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 * flow_dissector_key_icmp:
183 * type: ICMP type
184 * code: ICMP code
185 * id: session identifier
186 */
187 struct flow_dissector_key_icmp {
188 struct {
189 u8 type;
190 u8 code;
191 };
192 u16 id;
193 };
194
195 /**
196 * struct flow_dissector_key_eth_addrs:
197 * @src: source Ethernet address
198 * @dst: destination Ethernet address
199 */
200 struct flow_dissector_key_eth_addrs {
201 /* (dst,src) must be grouped, in the same way than in ETH header */
202 unsigned char dst[ETH_ALEN];
203 unsigned char src[ETH_ALEN];
204 };
205
206 /**
207 * struct flow_dissector_key_tcp:
208 * @flags: flags
209 */
210 struct flow_dissector_key_tcp {
211 __be16 flags;
212 };
213
214 /**
215 * struct flow_dissector_key_ip:
216 * @tos: tos
217 * @ttl: ttl
218 */
219 struct flow_dissector_key_ip {
220 __u8 tos;
221 __u8 ttl;
222 };
223
224 /**
225 * struct flow_dissector_key_meta:
226 * @ingress_ifindex: ingress ifindex
227 * @ingress_iftype: ingress interface type
228 */
229 struct flow_dissector_key_meta {
230 int ingress_ifindex;
231 u16 ingress_iftype;
232 };
233
234 /**
235 * struct flow_dissector_key_ct:
236 * @ct_state: conntrack state after converting with map
237 * @ct_mark: conttrack mark
238 * @ct_zone: conntrack zone
239 * @ct_labels: conntrack labels
240 */
241 struct flow_dissector_key_ct {
242 u16 ct_state;
243 u16 ct_zone;
244 u32 ct_mark;
245 u32 ct_labels[4];
246 };
247
248 /**
249 * struct flow_dissector_key_hash:
250 * @hash: hash value
251 */
252 struct flow_dissector_key_hash {
253 u32 hash;
254 };
255
256 enum flow_dissector_key_id {
257 FLOW_DISSECTOR_KEY_CONTROL, /* struct flow_dissector_key_control */
258 FLOW_DISSECTOR_KEY_BASIC, /* struct flow_dissector_key_basic */
259 FLOW_DISSECTOR_KEY_IPV4_ADDRS, /* struct flow_dissector_key_ipv4_addrs */
260 FLOW_DISSECTOR_KEY_IPV6_ADDRS, /* struct flow_dissector_key_ipv6_addrs */
261 FLOW_DISSECTOR_KEY_PORTS, /* struct flow_dissector_key_ports */
262 FLOW_DISSECTOR_KEY_PORTS_RANGE, /* struct flow_dissector_key_ports */
263 FLOW_DISSECTOR_KEY_ICMP, /* struct flow_dissector_key_icmp */
264 FLOW_DISSECTOR_KEY_ETH_ADDRS, /* struct flow_dissector_key_eth_addrs */
265 FLOW_DISSECTOR_KEY_TIPC, /* struct flow_dissector_key_tipc */
266 FLOW_DISSECTOR_KEY_ARP, /* struct flow_dissector_key_arp */
267 FLOW_DISSECTOR_KEY_VLAN, /* struct flow_dissector_key_vlan */
268 FLOW_DISSECTOR_KEY_FLOW_LABEL, /* struct flow_dissector_key_tags */
269 FLOW_DISSECTOR_KEY_GRE_KEYID, /* struct flow_dissector_key_keyid */
270 FLOW_DISSECTOR_KEY_MPLS_ENTROPY, /* struct flow_dissector_key_keyid */
271 FLOW_DISSECTOR_KEY_ENC_KEYID, /* struct flow_dissector_key_keyid */
272 FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS, /* struct flow_dissector_key_ipv4_addrs */
273 FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS, /* struct flow_dissector_key_ipv6_addrs */
274 FLOW_DISSECTOR_KEY_ENC_CONTROL, /* struct flow_dissector_key_control */
275 FLOW_DISSECTOR_KEY_ENC_PORTS, /* struct flow_dissector_key_ports */
276 FLOW_DISSECTOR_KEY_MPLS, /* struct flow_dissector_key_mpls */
277 FLOW_DISSECTOR_KEY_TCP, /* struct flow_dissector_key_tcp */
278 FLOW_DISSECTOR_KEY_IP, /* struct flow_dissector_key_ip */
279 FLOW_DISSECTOR_KEY_CVLAN, /* struct flow_dissector_key_vlan */
280 FLOW_DISSECTOR_KEY_ENC_IP, /* struct flow_dissector_key_ip */
281 FLOW_DISSECTOR_KEY_ENC_OPTS, /* struct flow_dissector_key_enc_opts */
282 FLOW_DISSECTOR_KEY_META, /* struct flow_dissector_key_meta */
283 FLOW_DISSECTOR_KEY_CT, /* struct flow_dissector_key_ct */
284 FLOW_DISSECTOR_KEY_HASH, /* struct flow_dissector_key_hash */
285
286 FLOW_DISSECTOR_KEY_MAX,
287 };
288
289 #define FLOW_DISSECTOR_F_PARSE_1ST_FRAG BIT(0)
290 #define FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL BIT(1)
291 #define FLOW_DISSECTOR_F_STOP_AT_ENCAP BIT(2)
292
293 struct flow_dissector_key {
294 enum flow_dissector_key_id key_id;
295 size_t offset; /* offset of struct flow_dissector_key_*
296 in target the struct */
297 };
298
299 struct flow_dissector {
300 unsigned int used_keys; /* each bit repesents presence of one key id */
301 unsigned short int offset[FLOW_DISSECTOR_KEY_MAX];
302 };
303
304 struct flow_keys_basic {
305 struct flow_dissector_key_control control;
306 struct flow_dissector_key_basic basic;
307 };
308
309 struct flow_keys {
310 struct flow_dissector_key_control control;
311 #define FLOW_KEYS_HASH_START_FIELD basic
312 struct flow_dissector_key_basic basic __aligned(SIPHASH_ALIGNMENT);
313 struct flow_dissector_key_tags tags;
314 struct flow_dissector_key_vlan vlan;
315 struct flow_dissector_key_vlan cvlan;
316 struct flow_dissector_key_keyid keyid;
317 struct flow_dissector_key_ports ports;
318 struct flow_dissector_key_icmp icmp;
319 /* 'addrs' must be the last member */
320 struct flow_dissector_key_addrs addrs;
321 };
322
323 #define FLOW_KEYS_HASH_OFFSET \
324 offsetof(struct flow_keys, FLOW_KEYS_HASH_START_FIELD)
325
326 __be32 flow_get_u32_src(const struct flow_keys *flow);
327 __be32 flow_get_u32_dst(const struct flow_keys *flow);
328
329 extern struct flow_dissector flow_keys_dissector;
330 extern struct flow_dissector flow_keys_basic_dissector;
331
332 /* struct flow_keys_digest:
333 *
334 * This structure is used to hold a digest of the full flow keys. This is a
335 * larger "hash" of a flow to allow definitively matching specific flows where
336 * the 32 bit skb->hash is not large enough. The size is limited to 16 bytes so
337 * that it can be used in CB of skb (see sch_choke for an example).
338 */
339 #define FLOW_KEYS_DIGEST_LEN 16
340 struct flow_keys_digest {
341 u8 data[FLOW_KEYS_DIGEST_LEN];
342 };
343
344 void make_flow_keys_digest(struct flow_keys_digest *digest,
345 const struct flow_keys *flow);
346
flow_keys_have_l4(const struct flow_keys * keys)347 static inline bool flow_keys_have_l4(const struct flow_keys *keys)
348 {
349 return (keys->ports.ports || keys->tags.flow_label);
350 }
351
352 u32 flow_hash_from_keys(struct flow_keys *keys);
353 void skb_flow_get_icmp_tci(const struct sk_buff *skb,
354 struct flow_dissector_key_icmp *key_icmp,
355 void *data, int thoff, int hlen);
356
dissector_uses_key(const struct flow_dissector * flow_dissector,enum flow_dissector_key_id key_id)357 static inline bool dissector_uses_key(const struct flow_dissector *flow_dissector,
358 enum flow_dissector_key_id key_id)
359 {
360 return flow_dissector->used_keys & (1 << key_id);
361 }
362
skb_flow_dissector_target(struct flow_dissector * flow_dissector,enum flow_dissector_key_id key_id,void * target_container)363 static inline void *skb_flow_dissector_target(struct flow_dissector *flow_dissector,
364 enum flow_dissector_key_id key_id,
365 void *target_container)
366 {
367 return ((char *)target_container) + flow_dissector->offset[key_id];
368 }
369
370 struct bpf_flow_dissector {
371 struct bpf_flow_keys *flow_keys;
372 const struct sk_buff *skb;
373 void *data;
374 void *data_end;
375 };
376
377 static inline void
flow_dissector_init_keys(struct flow_dissector_key_control * key_control,struct flow_dissector_key_basic * key_basic)378 flow_dissector_init_keys(struct flow_dissector_key_control *key_control,
379 struct flow_dissector_key_basic *key_basic)
380 {
381 memset(key_control, 0, sizeof(*key_control));
382 memset(key_basic, 0, sizeof(*key_basic));
383 }
384
385 #ifdef CONFIG_BPF_SYSCALL
386 int flow_dissector_bpf_prog_attach_check(struct net *net,
387 struct bpf_prog *prog);
388 #endif /* CONFIG_BPF_SYSCALL */
389
390 #endif
391