xref: /openbmc/linux/include/net/flow_dissector.h (revision d236d361)
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 enum flow_dissector_key_id {
161 	FLOW_DISSECTOR_KEY_CONTROL, /* struct flow_dissector_key_control */
162 	FLOW_DISSECTOR_KEY_BASIC, /* struct flow_dissector_key_basic */
163 	FLOW_DISSECTOR_KEY_IPV4_ADDRS, /* struct flow_dissector_key_ipv4_addrs */
164 	FLOW_DISSECTOR_KEY_IPV6_ADDRS, /* struct flow_dissector_key_ipv6_addrs */
165 	FLOW_DISSECTOR_KEY_PORTS, /* struct flow_dissector_key_ports */
166 	FLOW_DISSECTOR_KEY_ICMP, /* struct flow_dissector_key_icmp */
167 	FLOW_DISSECTOR_KEY_ETH_ADDRS, /* struct flow_dissector_key_eth_addrs */
168 	FLOW_DISSECTOR_KEY_TIPC_ADDRS, /* struct flow_dissector_key_tipc_addrs */
169 	FLOW_DISSECTOR_KEY_ARP, /* struct flow_dissector_key_arp */
170 	FLOW_DISSECTOR_KEY_VLAN, /* struct flow_dissector_key_flow_vlan */
171 	FLOW_DISSECTOR_KEY_FLOW_LABEL, /* struct flow_dissector_key_flow_tags */
172 	FLOW_DISSECTOR_KEY_GRE_KEYID, /* struct flow_dissector_key_keyid */
173 	FLOW_DISSECTOR_KEY_MPLS_ENTROPY, /* struct flow_dissector_key_keyid */
174 	FLOW_DISSECTOR_KEY_ENC_KEYID, /* struct flow_dissector_key_keyid */
175 	FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS, /* struct flow_dissector_key_ipv4_addrs */
176 	FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS, /* struct flow_dissector_key_ipv6_addrs */
177 	FLOW_DISSECTOR_KEY_ENC_CONTROL, /* struct flow_dissector_key_control */
178 	FLOW_DISSECTOR_KEY_ENC_PORTS, /* struct flow_dissector_key_ports */
179 	FLOW_DISSECTOR_KEY_MPLS, /* struct flow_dissector_key_mpls */
180 
181 	FLOW_DISSECTOR_KEY_MAX,
182 };
183 
184 #define FLOW_DISSECTOR_F_PARSE_1ST_FRAG		BIT(0)
185 #define FLOW_DISSECTOR_F_STOP_AT_L3		BIT(1)
186 #define FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL	BIT(2)
187 #define FLOW_DISSECTOR_F_STOP_AT_ENCAP		BIT(3)
188 
189 struct flow_dissector_key {
190 	enum flow_dissector_key_id key_id;
191 	size_t offset; /* offset of struct flow_dissector_key_*
192 			  in target the struct */
193 };
194 
195 struct flow_dissector {
196 	unsigned int used_keys; /* each bit repesents presence of one key id */
197 	unsigned short int offset[FLOW_DISSECTOR_KEY_MAX];
198 };
199 
200 struct flow_keys {
201 	struct flow_dissector_key_control control;
202 #define FLOW_KEYS_HASH_START_FIELD basic
203 	struct flow_dissector_key_basic basic;
204 	struct flow_dissector_key_tags tags;
205 	struct flow_dissector_key_vlan vlan;
206 	struct flow_dissector_key_keyid keyid;
207 	struct flow_dissector_key_ports ports;
208 	struct flow_dissector_key_addrs addrs;
209 };
210 
211 #define FLOW_KEYS_HASH_OFFSET		\
212 	offsetof(struct flow_keys, FLOW_KEYS_HASH_START_FIELD)
213 
214 __be32 flow_get_u32_src(const struct flow_keys *flow);
215 __be32 flow_get_u32_dst(const struct flow_keys *flow);
216 
217 extern struct flow_dissector flow_keys_dissector;
218 extern struct flow_dissector flow_keys_buf_dissector;
219 
220 /* struct flow_keys_digest:
221  *
222  * This structure is used to hold a digest of the full flow keys. This is a
223  * larger "hash" of a flow to allow definitively matching specific flows where
224  * the 32 bit skb->hash is not large enough. The size is limited to 16 bytes so
225  * that it can by used in CB of skb (see sch_choke for an example).
226  */
227 #define FLOW_KEYS_DIGEST_LEN	16
228 struct flow_keys_digest {
229 	u8	data[FLOW_KEYS_DIGEST_LEN];
230 };
231 
232 void make_flow_keys_digest(struct flow_keys_digest *digest,
233 			   const struct flow_keys *flow);
234 
235 static inline bool flow_keys_have_l4(const struct flow_keys *keys)
236 {
237 	return (keys->ports.ports || keys->tags.flow_label);
238 }
239 
240 u32 flow_hash_from_keys(struct flow_keys *keys);
241 
242 static inline bool dissector_uses_key(const struct flow_dissector *flow_dissector,
243 				      enum flow_dissector_key_id key_id)
244 {
245 	return flow_dissector->used_keys & (1 << key_id);
246 }
247 
248 static inline void *skb_flow_dissector_target(struct flow_dissector *flow_dissector,
249 					      enum flow_dissector_key_id key_id,
250 					      void *target_container)
251 {
252 	return ((char *)target_container) + flow_dissector->offset[key_id];
253 }
254 
255 #endif
256