xref: /openbmc/linux/include/net/flow_dissector.h (revision 4da722ca19f30f7db250db808d1ab1703607a932)
1 #ifndef _NET_FLOW_DISSECTOR_H
2 #define _NET_FLOW_DISSECTOR_H
3 
4 #include <linux/types.h>
5 #include <linux/in6.h>
6 #include <uapi/linux/if_ether.h>
7 
8 /**
9  * struct flow_dissector_key_control:
10  * @thoff: Transport header offset
11  */
12 struct flow_dissector_key_control {
13 	u16	thoff;
14 	u16	addr_type;
15 	u32	flags;
16 };
17 
18 #define FLOW_DIS_IS_FRAGMENT	BIT(0)
19 #define FLOW_DIS_FIRST_FRAG	BIT(1)
20 #define FLOW_DIS_ENCAPSULATION	BIT(2)
21 
22 /**
23  * struct flow_dissector_key_basic:
24  * @thoff: Transport header offset
25  * @n_proto: Network header protocol (eg. IPv4/IPv6)
26  * @ip_proto: Transport header protocol (eg. TCP/UDP)
27  */
28 struct flow_dissector_key_basic {
29 	__be16	n_proto;
30 	u8	ip_proto;
31 	u8	padding;
32 };
33 
34 struct flow_dissector_key_tags {
35 	u32	flow_label;
36 };
37 
38 struct flow_dissector_key_vlan {
39 	u16	vlan_id:12,
40 		vlan_priority:3;
41 	u16	padding;
42 };
43 
44 struct flow_dissector_key_mpls {
45 	u32	mpls_ttl:8,
46 		mpls_bos:1,
47 		mpls_tc:3,
48 		mpls_label:20;
49 };
50 
51 struct flow_dissector_key_keyid {
52 	__be32	keyid;
53 };
54 
55 /**
56  * struct flow_dissector_key_ipv4_addrs:
57  * @src: source ip address
58  * @dst: destination ip address
59  */
60 struct flow_dissector_key_ipv4_addrs {
61 	/* (src,dst) must be grouped, in the same way than in IP header */
62 	__be32 src;
63 	__be32 dst;
64 };
65 
66 /**
67  * struct flow_dissector_key_ipv6_addrs:
68  * @src: source ip address
69  * @dst: destination ip address
70  */
71 struct flow_dissector_key_ipv6_addrs {
72 	/* (src,dst) must be grouped, in the same way than in IP header */
73 	struct in6_addr src;
74 	struct in6_addr dst;
75 };
76 
77 /**
78  * struct flow_dissector_key_tipc_addrs:
79  * @srcnode: source node address
80  */
81 struct flow_dissector_key_tipc_addrs {
82 	__be32 srcnode;
83 };
84 
85 /**
86  * struct flow_dissector_key_addrs:
87  * @v4addrs: IPv4 addresses
88  * @v6addrs: IPv6 addresses
89  */
90 struct flow_dissector_key_addrs {
91 	union {
92 		struct flow_dissector_key_ipv4_addrs v4addrs;
93 		struct flow_dissector_key_ipv6_addrs v6addrs;
94 		struct flow_dissector_key_tipc_addrs tipcaddrs;
95 	};
96 };
97 
98 /**
99  * flow_dissector_key_arp:
100  *	@ports: Operation, source and target addresses for an ARP header
101  *              for Ethernet hardware addresses and IPv4 protocol addresses
102  *		sip: Sender IP address
103  *		tip: Target IP address
104  *		op:  Operation
105  *		sha: Sender hardware address
106  *		tpa: Target hardware address
107  */
108 struct flow_dissector_key_arp {
109 	__u32 sip;
110 	__u32 tip;
111 	__u8 op;
112 	unsigned char sha[ETH_ALEN];
113 	unsigned char tha[ETH_ALEN];
114 };
115 
116 /**
117  * flow_dissector_key_tp_ports:
118  *	@ports: port numbers of Transport header
119  *		src: source port number
120  *		dst: destination port number
121  */
122 struct flow_dissector_key_ports {
123 	union {
124 		__be32 ports;
125 		struct {
126 			__be16 src;
127 			__be16 dst;
128 		};
129 	};
130 };
131 
132 /**
133  * flow_dissector_key_icmp:
134  *	@ports: type and code of ICMP header
135  *		icmp: ICMP type (high) and code (low)
136  *		type: ICMP type
137  *		code: ICMP code
138  */
139 struct flow_dissector_key_icmp {
140 	union {
141 		__be16 icmp;
142 		struct {
143 			u8 type;
144 			u8 code;
145 		};
146 	};
147 };
148 
149 /**
150  * struct flow_dissector_key_eth_addrs:
151  * @src: source Ethernet address
152  * @dst: destination Ethernet address
153  */
154 struct flow_dissector_key_eth_addrs {
155 	/* (dst,src) must be grouped, in the same way than in ETH header */
156 	unsigned char dst[ETH_ALEN];
157 	unsigned char src[ETH_ALEN];
158 };
159 
160 /**
161  * struct flow_dissector_key_tcp:
162  * @flags: flags
163  */
164 struct flow_dissector_key_tcp {
165 	__be16 flags;
166 };
167 
168 /**
169  * struct flow_dissector_key_ip:
170  * @tos: tos
171  * @ttl: ttl
172  */
173 struct flow_dissector_key_ip {
174 	__u8	tos;
175 	__u8	ttl;
176 };
177 
178 enum flow_dissector_key_id {
179 	FLOW_DISSECTOR_KEY_CONTROL, /* struct flow_dissector_key_control */
180 	FLOW_DISSECTOR_KEY_BASIC, /* struct flow_dissector_key_basic */
181 	FLOW_DISSECTOR_KEY_IPV4_ADDRS, /* struct flow_dissector_key_ipv4_addrs */
182 	FLOW_DISSECTOR_KEY_IPV6_ADDRS, /* struct flow_dissector_key_ipv6_addrs */
183 	FLOW_DISSECTOR_KEY_PORTS, /* struct flow_dissector_key_ports */
184 	FLOW_DISSECTOR_KEY_ICMP, /* struct flow_dissector_key_icmp */
185 	FLOW_DISSECTOR_KEY_ETH_ADDRS, /* struct flow_dissector_key_eth_addrs */
186 	FLOW_DISSECTOR_KEY_TIPC_ADDRS, /* struct flow_dissector_key_tipc_addrs */
187 	FLOW_DISSECTOR_KEY_ARP, /* struct flow_dissector_key_arp */
188 	FLOW_DISSECTOR_KEY_VLAN, /* struct flow_dissector_key_flow_vlan */
189 	FLOW_DISSECTOR_KEY_FLOW_LABEL, /* struct flow_dissector_key_flow_tags */
190 	FLOW_DISSECTOR_KEY_GRE_KEYID, /* struct flow_dissector_key_keyid */
191 	FLOW_DISSECTOR_KEY_MPLS_ENTROPY, /* struct flow_dissector_key_keyid */
192 	FLOW_DISSECTOR_KEY_ENC_KEYID, /* struct flow_dissector_key_keyid */
193 	FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS, /* struct flow_dissector_key_ipv4_addrs */
194 	FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS, /* struct flow_dissector_key_ipv6_addrs */
195 	FLOW_DISSECTOR_KEY_ENC_CONTROL, /* struct flow_dissector_key_control */
196 	FLOW_DISSECTOR_KEY_ENC_PORTS, /* struct flow_dissector_key_ports */
197 	FLOW_DISSECTOR_KEY_MPLS, /* struct flow_dissector_key_mpls */
198 	FLOW_DISSECTOR_KEY_TCP, /* struct flow_dissector_key_tcp */
199 	FLOW_DISSECTOR_KEY_IP, /* struct flow_dissector_key_ip */
200 
201 	FLOW_DISSECTOR_KEY_MAX,
202 };
203 
204 #define FLOW_DISSECTOR_F_PARSE_1ST_FRAG		BIT(0)
205 #define FLOW_DISSECTOR_F_STOP_AT_L3		BIT(1)
206 #define FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL	BIT(2)
207 #define FLOW_DISSECTOR_F_STOP_AT_ENCAP		BIT(3)
208 
209 struct flow_dissector_key {
210 	enum flow_dissector_key_id key_id;
211 	size_t offset; /* offset of struct flow_dissector_key_*
212 			  in target the struct */
213 };
214 
215 struct flow_dissector {
216 	unsigned int used_keys; /* each bit repesents presence of one key id */
217 	unsigned short int offset[FLOW_DISSECTOR_KEY_MAX];
218 };
219 
220 struct flow_keys {
221 	struct flow_dissector_key_control control;
222 #define FLOW_KEYS_HASH_START_FIELD basic
223 	struct flow_dissector_key_basic basic;
224 	struct flow_dissector_key_tags tags;
225 	struct flow_dissector_key_vlan vlan;
226 	struct flow_dissector_key_keyid keyid;
227 	struct flow_dissector_key_ports ports;
228 	struct flow_dissector_key_addrs addrs;
229 };
230 
231 #define FLOW_KEYS_HASH_OFFSET		\
232 	offsetof(struct flow_keys, FLOW_KEYS_HASH_START_FIELD)
233 
234 __be32 flow_get_u32_src(const struct flow_keys *flow);
235 __be32 flow_get_u32_dst(const struct flow_keys *flow);
236 
237 extern struct flow_dissector flow_keys_dissector;
238 extern struct flow_dissector flow_keys_buf_dissector;
239 
240 /* struct flow_keys_digest:
241  *
242  * This structure is used to hold a digest of the full flow keys. This is a
243  * larger "hash" of a flow to allow definitively matching specific flows where
244  * the 32 bit skb->hash is not large enough. The size is limited to 16 bytes so
245  * that it can by used in CB of skb (see sch_choke for an example).
246  */
247 #define FLOW_KEYS_DIGEST_LEN	16
248 struct flow_keys_digest {
249 	u8	data[FLOW_KEYS_DIGEST_LEN];
250 };
251 
252 void make_flow_keys_digest(struct flow_keys_digest *digest,
253 			   const struct flow_keys *flow);
254 
255 static inline bool flow_keys_have_l4(const struct flow_keys *keys)
256 {
257 	return (keys->ports.ports || keys->tags.flow_label);
258 }
259 
260 u32 flow_hash_from_keys(struct flow_keys *keys);
261 
262 static inline bool dissector_uses_key(const struct flow_dissector *flow_dissector,
263 				      enum flow_dissector_key_id key_id)
264 {
265 	return flow_dissector->used_keys & (1 << key_id);
266 }
267 
268 static inline void *skb_flow_dissector_target(struct flow_dissector *flow_dissector,
269 					      enum flow_dissector_key_id key_id,
270 					      void *target_container)
271 {
272 	return ((char *)target_container) + flow_dissector->offset[key_id];
273 }
274 
275 #endif
276