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 /**
12 * struct flow_dissector_key_control:
13 * @thoff: Transport header offset
14 */
15 struct flow_dissector_key_control {
16 u16 thoff;
17 u16 addr_type;
18 u32 flags;
19 };
20
21 #define FLOW_DIS_IS_FRAGMENT BIT(0)
22 #define FLOW_DIS_FIRST_FRAG BIT(1)
23 #define FLOW_DIS_ENCAPSULATION BIT(2)
24
25 enum flow_dissect_ret {
26 FLOW_DISSECT_RET_OUT_GOOD,
27 FLOW_DISSECT_RET_OUT_BAD,
28 FLOW_DISSECT_RET_PROTO_AGAIN,
29 FLOW_DISSECT_RET_IPPROTO_AGAIN,
30 FLOW_DISSECT_RET_CONTINUE,
31 };
32
33 /**
34 * struct flow_dissector_key_basic:
35 * @thoff: Transport header offset
36 * @n_proto: Network header protocol (eg. IPv4/IPv6)
37 * @ip_proto: Transport header protocol (eg. TCP/UDP)
38 */
39 struct flow_dissector_key_basic {
40 __be16 n_proto;
41 u8 ip_proto;
42 u8 padding;
43 };
44
45 struct flow_dissector_key_tags {
46 u32 flow_label;
47 };
48
49 struct flow_dissector_key_vlan {
50 u16 vlan_id:12,
51 vlan_priority:3;
52 u16 padding;
53 };
54
55 struct flow_dissector_key_mpls {
56 u32 mpls_ttl:8,
57 mpls_bos:1,
58 mpls_tc:3,
59 mpls_label:20;
60 };
61
62 struct flow_dissector_key_keyid {
63 __be32 keyid;
64 };
65
66 /**
67 * struct flow_dissector_key_ipv4_addrs:
68 * @src: source ip address
69 * @dst: destination ip address
70 */
71 struct flow_dissector_key_ipv4_addrs {
72 /* (src,dst) must be grouped, in the same way than in IP header */
73 __be32 src;
74 __be32 dst;
75 };
76
77 /**
78 * struct flow_dissector_key_ipv6_addrs:
79 * @src: source ip address
80 * @dst: destination ip address
81 */
82 struct flow_dissector_key_ipv6_addrs {
83 /* (src,dst) must be grouped, in the same way than in IP header */
84 struct in6_addr src;
85 struct in6_addr dst;
86 };
87
88 /**
89 * struct flow_dissector_key_tipc_addrs:
90 * @srcnode: source node address
91 */
92 struct flow_dissector_key_tipc_addrs {
93 __be32 srcnode;
94 };
95
96 /**
97 * struct flow_dissector_key_addrs:
98 * @v4addrs: IPv4 addresses
99 * @v6addrs: IPv6 addresses
100 */
101 struct flow_dissector_key_addrs {
102 union {
103 struct flow_dissector_key_ipv4_addrs v4addrs;
104 struct flow_dissector_key_ipv6_addrs v6addrs;
105 struct flow_dissector_key_tipc_addrs tipcaddrs;
106 };
107 };
108
109 /**
110 * flow_dissector_key_arp:
111 * @ports: Operation, source and target addresses for an ARP header
112 * for Ethernet hardware addresses and IPv4 protocol addresses
113 * sip: Sender IP address
114 * tip: Target IP address
115 * op: Operation
116 * sha: Sender hardware address
117 * tpa: Target hardware address
118 */
119 struct flow_dissector_key_arp {
120 __u32 sip;
121 __u32 tip;
122 __u8 op;
123 unsigned char sha[ETH_ALEN];
124 unsigned char tha[ETH_ALEN];
125 };
126
127 /**
128 * flow_dissector_key_tp_ports:
129 * @ports: port numbers of Transport header
130 * src: source port number
131 * dst: destination port number
132 */
133 struct flow_dissector_key_ports {
134 union {
135 __be32 ports;
136 struct {
137 __be16 src;
138 __be16 dst;
139 };
140 };
141 };
142
143 /**
144 * flow_dissector_key_icmp:
145 * @ports: type and code of ICMP header
146 * icmp: ICMP type (high) and code (low)
147 * type: ICMP type
148 * code: ICMP code
149 */
150 struct flow_dissector_key_icmp {
151 union {
152 __be16 icmp;
153 struct {
154 u8 type;
155 u8 code;
156 };
157 };
158 };
159
160 /**
161 * struct flow_dissector_key_eth_addrs:
162 * @src: source Ethernet address
163 * @dst: destination Ethernet address
164 */
165 struct flow_dissector_key_eth_addrs {
166 /* (dst,src) must be grouped, in the same way than in ETH header */
167 unsigned char dst[ETH_ALEN];
168 unsigned char src[ETH_ALEN];
169 };
170
171 /**
172 * struct flow_dissector_key_tcp:
173 * @flags: flags
174 */
175 struct flow_dissector_key_tcp {
176 __be16 flags;
177 };
178
179 /**
180 * struct flow_dissector_key_ip:
181 * @tos: tos
182 * @ttl: ttl
183 */
184 struct flow_dissector_key_ip {
185 __u8 tos;
186 __u8 ttl;
187 };
188
189 enum flow_dissector_key_id {
190 FLOW_DISSECTOR_KEY_CONTROL, /* struct flow_dissector_key_control */
191 FLOW_DISSECTOR_KEY_BASIC, /* struct flow_dissector_key_basic */
192 FLOW_DISSECTOR_KEY_IPV4_ADDRS, /* struct flow_dissector_key_ipv4_addrs */
193 FLOW_DISSECTOR_KEY_IPV6_ADDRS, /* struct flow_dissector_key_ipv6_addrs */
194 FLOW_DISSECTOR_KEY_PORTS, /* struct flow_dissector_key_ports */
195 FLOW_DISSECTOR_KEY_ICMP, /* struct flow_dissector_key_icmp */
196 FLOW_DISSECTOR_KEY_ETH_ADDRS, /* struct flow_dissector_key_eth_addrs */
197 FLOW_DISSECTOR_KEY_TIPC_ADDRS, /* struct flow_dissector_key_tipc_addrs */
198 FLOW_DISSECTOR_KEY_ARP, /* struct flow_dissector_key_arp */
199 FLOW_DISSECTOR_KEY_VLAN, /* struct flow_dissector_key_flow_vlan */
200 FLOW_DISSECTOR_KEY_FLOW_LABEL, /* struct flow_dissector_key_flow_tags */
201 FLOW_DISSECTOR_KEY_GRE_KEYID, /* struct flow_dissector_key_keyid */
202 FLOW_DISSECTOR_KEY_MPLS_ENTROPY, /* struct flow_dissector_key_keyid */
203 FLOW_DISSECTOR_KEY_ENC_KEYID, /* struct flow_dissector_key_keyid */
204 FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS, /* struct flow_dissector_key_ipv4_addrs */
205 FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS, /* struct flow_dissector_key_ipv6_addrs */
206 FLOW_DISSECTOR_KEY_ENC_CONTROL, /* struct flow_dissector_key_control */
207 FLOW_DISSECTOR_KEY_ENC_PORTS, /* struct flow_dissector_key_ports */
208 FLOW_DISSECTOR_KEY_MPLS, /* struct flow_dissector_key_mpls */
209 FLOW_DISSECTOR_KEY_TCP, /* struct flow_dissector_key_tcp */
210 FLOW_DISSECTOR_KEY_IP, /* struct flow_dissector_key_ip */
211
212 FLOW_DISSECTOR_KEY_MAX,
213 };
214
215 #define FLOW_DISSECTOR_F_PARSE_1ST_FRAG BIT(0)
216 #define FLOW_DISSECTOR_F_STOP_AT_L3 BIT(1)
217 #define FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL BIT(2)
218 #define FLOW_DISSECTOR_F_STOP_AT_ENCAP BIT(3)
219
220 struct flow_dissector_key {
221 enum flow_dissector_key_id key_id;
222 size_t offset; /* offset of struct flow_dissector_key_*
223 in target the struct */
224 };
225
226 struct flow_dissector {
227 unsigned int used_keys; /* each bit repesents presence of one key id */
228 unsigned short int offset[FLOW_DISSECTOR_KEY_MAX];
229 };
230
231 struct flow_keys {
232 struct flow_dissector_key_control control;
233 #define FLOW_KEYS_HASH_START_FIELD basic
234 struct flow_dissector_key_basic basic __aligned(SIPHASH_ALIGNMENT);
235 struct flow_dissector_key_tags tags;
236 struct flow_dissector_key_vlan vlan;
237 struct flow_dissector_key_keyid keyid;
238 struct flow_dissector_key_ports ports;
239 struct flow_dissector_key_addrs addrs;
240 };
241
242 #define FLOW_KEYS_HASH_OFFSET \
243 offsetof(struct flow_keys, FLOW_KEYS_HASH_START_FIELD)
244
245 __be32 flow_get_u32_src(const struct flow_keys *flow);
246 __be32 flow_get_u32_dst(const struct flow_keys *flow);
247
248 extern struct flow_dissector flow_keys_dissector;
249 extern struct flow_dissector flow_keys_buf_dissector;
250
251 /* struct flow_keys_digest:
252 *
253 * This structure is used to hold a digest of the full flow keys. This is a
254 * larger "hash" of a flow to allow definitively matching specific flows where
255 * the 32 bit skb->hash is not large enough. The size is limited to 16 bytes so
256 * that it can by used in CB of skb (see sch_choke for an example).
257 */
258 #define FLOW_KEYS_DIGEST_LEN 16
259 struct flow_keys_digest {
260 u8 data[FLOW_KEYS_DIGEST_LEN];
261 };
262
263 void make_flow_keys_digest(struct flow_keys_digest *digest,
264 const struct flow_keys *flow);
265
flow_keys_have_l4(const struct flow_keys * keys)266 static inline bool flow_keys_have_l4(const struct flow_keys *keys)
267 {
268 return (keys->ports.ports || keys->tags.flow_label);
269 }
270
271 u32 flow_hash_from_keys(struct flow_keys *keys);
272
dissector_uses_key(const struct flow_dissector * flow_dissector,enum flow_dissector_key_id key_id)273 static inline bool dissector_uses_key(const struct flow_dissector *flow_dissector,
274 enum flow_dissector_key_id key_id)
275 {
276 return flow_dissector->used_keys & (1 << key_id);
277 }
278
skb_flow_dissector_target(struct flow_dissector * flow_dissector,enum flow_dissector_key_id key_id,void * target_container)279 static inline void *skb_flow_dissector_target(struct flow_dissector *flow_dissector,
280 enum flow_dissector_key_id key_id,
281 void *target_container)
282 {
283 return ((char *)target_container) + flow_dissector->offset[key_id];
284 }
285
286 static inline void
flow_dissector_init_keys(struct flow_dissector_key_control * key_control,struct flow_dissector_key_basic * key_basic)287 flow_dissector_init_keys(struct flow_dissector_key_control *key_control,
288 struct flow_dissector_key_basic *key_basic)
289 {
290 memset(key_control, 0, sizeof(*key_control));
291 memset(key_basic, 0, sizeof(*key_basic));
292 }
293
294 #endif
295