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 <linux/siphash.h>
7 #include <linux/string.h>
8 #include <uapi/linux/if_ether.h>
9
10 /**
11 * struct flow_dissector_key_control:
12 * @thoff: Transport header offset
13 */
14 struct flow_dissector_key_control {
15 u16 thoff;
16 u16 addr_type;
17 u32 flags;
18 };
19
20 #define FLOW_DIS_IS_FRAGMENT BIT(0)
21 #define FLOW_DIS_FIRST_FRAG BIT(1)
22 #define FLOW_DIS_ENCAPSULATION BIT(2)
23
24 /**
25 * struct flow_dissector_key_basic:
26 * @thoff: Transport header offset
27 * @n_proto: Network header protocol (eg. IPv4/IPv6)
28 * @ip_proto: Transport header protocol (eg. TCP/UDP)
29 */
30 struct flow_dissector_key_basic {
31 __be16 n_proto;
32 u8 ip_proto;
33 u8 padding;
34 };
35
36 struct flow_dissector_key_tags {
37 u32 vlan_id:12,
38 flow_label:20;
39 };
40
41 struct flow_dissector_key_keyid {
42 __be32 keyid;
43 };
44
45 /**
46 * struct flow_dissector_key_ipv4_addrs:
47 * @src: source ip address
48 * @dst: destination ip address
49 */
50 struct flow_dissector_key_ipv4_addrs {
51 /* (src,dst) must be grouped, in the same way than in IP header */
52 __be32 src;
53 __be32 dst;
54 };
55
56 /**
57 * struct flow_dissector_key_ipv6_addrs:
58 * @src: source ip address
59 * @dst: destination ip address
60 */
61 struct flow_dissector_key_ipv6_addrs {
62 /* (src,dst) must be grouped, in the same way than in IP header */
63 struct in6_addr src;
64 struct in6_addr dst;
65 };
66
67 /**
68 * struct flow_dissector_key_tipc_addrs:
69 * @srcnode: source node address
70 */
71 struct flow_dissector_key_tipc_addrs {
72 __be32 srcnode;
73 };
74
75 /**
76 * struct flow_dissector_key_addrs:
77 * @v4addrs: IPv4 addresses
78 * @v6addrs: IPv6 addresses
79 */
80 struct flow_dissector_key_addrs {
81 union {
82 struct flow_dissector_key_ipv4_addrs v4addrs;
83 struct flow_dissector_key_ipv6_addrs v6addrs;
84 struct flow_dissector_key_tipc_addrs tipcaddrs;
85 };
86 };
87
88 /**
89 * flow_dissector_key_tp_ports:
90 * @ports: port numbers of Transport header
91 * src: source port number
92 * dst: destination port number
93 */
94 struct flow_dissector_key_ports {
95 union {
96 __be32 ports;
97 struct {
98 __be16 src;
99 __be16 dst;
100 };
101 };
102 };
103
104
105 /**
106 * struct flow_dissector_key_eth_addrs:
107 * @src: source Ethernet address
108 * @dst: destination Ethernet address
109 */
110 struct flow_dissector_key_eth_addrs {
111 /* (dst,src) must be grouped, in the same way than in ETH header */
112 unsigned char dst[ETH_ALEN];
113 unsigned char src[ETH_ALEN];
114 };
115
116 enum flow_dissector_key_id {
117 FLOW_DISSECTOR_KEY_CONTROL, /* struct flow_dissector_key_control */
118 FLOW_DISSECTOR_KEY_BASIC, /* struct flow_dissector_key_basic */
119 FLOW_DISSECTOR_KEY_IPV4_ADDRS, /* struct flow_dissector_key_ipv4_addrs */
120 FLOW_DISSECTOR_KEY_IPV6_ADDRS, /* struct flow_dissector_key_ipv6_addrs */
121 FLOW_DISSECTOR_KEY_PORTS, /* struct flow_dissector_key_ports */
122 FLOW_DISSECTOR_KEY_ETH_ADDRS, /* struct flow_dissector_key_eth_addrs */
123 FLOW_DISSECTOR_KEY_TIPC_ADDRS, /* struct flow_dissector_key_tipc_addrs */
124 FLOW_DISSECTOR_KEY_VLANID, /* struct flow_dissector_key_flow_tags */
125 FLOW_DISSECTOR_KEY_FLOW_LABEL, /* struct flow_dissector_key_flow_tags */
126 FLOW_DISSECTOR_KEY_GRE_KEYID, /* struct flow_dissector_key_keyid */
127 FLOW_DISSECTOR_KEY_MPLS_ENTROPY, /* struct flow_dissector_key_keyid */
128
129 FLOW_DISSECTOR_KEY_MAX,
130 };
131
132 #define FLOW_DISSECTOR_F_PARSE_1ST_FRAG BIT(0)
133 #define FLOW_DISSECTOR_F_STOP_AT_L3 BIT(1)
134 #define FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL BIT(2)
135 #define FLOW_DISSECTOR_F_STOP_AT_ENCAP BIT(3)
136
137 struct flow_dissector_key {
138 enum flow_dissector_key_id key_id;
139 size_t offset; /* offset of struct flow_dissector_key_*
140 in target the struct */
141 };
142
143 struct flow_dissector {
144 unsigned int used_keys; /* each bit repesents presence of one key id */
145 unsigned short int offset[FLOW_DISSECTOR_KEY_MAX];
146 };
147
148 struct flow_keys {
149 struct flow_dissector_key_control control;
150 #define FLOW_KEYS_HASH_START_FIELD basic
151 struct flow_dissector_key_basic basic __aligned(SIPHASH_ALIGNMENT);
152 struct flow_dissector_key_tags tags;
153 struct flow_dissector_key_keyid keyid;
154 struct flow_dissector_key_ports ports;
155 struct flow_dissector_key_addrs addrs;
156 };
157
158 #define FLOW_KEYS_HASH_OFFSET \
159 offsetof(struct flow_keys, FLOW_KEYS_HASH_START_FIELD)
160
161 __be32 flow_get_u32_src(const struct flow_keys *flow);
162 __be32 flow_get_u32_dst(const struct flow_keys *flow);
163
164 extern struct flow_dissector flow_keys_dissector;
165 extern struct flow_dissector flow_keys_buf_dissector;
166
167 /* struct flow_keys_digest:
168 *
169 * This structure is used to hold a digest of the full flow keys. This is a
170 * larger "hash" of a flow to allow definitively matching specific flows where
171 * the 32 bit skb->hash is not large enough. The size is limited to 16 bytes so
172 * that it can by used in CB of skb (see sch_choke for an example).
173 */
174 #define FLOW_KEYS_DIGEST_LEN 16
175 struct flow_keys_digest {
176 u8 data[FLOW_KEYS_DIGEST_LEN];
177 };
178
179 void make_flow_keys_digest(struct flow_keys_digest *digest,
180 const struct flow_keys *flow);
181
flow_keys_have_l4(struct flow_keys * keys)182 static inline bool flow_keys_have_l4(struct flow_keys *keys)
183 {
184 return (keys->ports.ports || keys->tags.flow_label);
185 }
186
187 u32 flow_hash_from_keys(struct flow_keys *keys);
188
189 static inline void
flow_dissector_init_keys(struct flow_dissector_key_control * key_control,struct flow_dissector_key_basic * key_basic)190 flow_dissector_init_keys(struct flow_dissector_key_control *key_control,
191 struct flow_dissector_key_basic *key_basic)
192 {
193 memset(key_control, 0, sizeof(*key_control));
194 memset(key_basic, 0, sizeof(*key_basic));
195 }
196
197 #endif
198