xref: /linux/net/openvswitch/flow.h (revision 3bdab16c55f57a24245c97d707241dd9b48d1a91)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Copyright (c) 2007-2017 Nicira, Inc.
4  */
5 
6 #ifndef FLOW_H
7 #define FLOW_H 1
8 
9 #include <linux/cache.h>
10 #include <linux/kernel.h>
11 #include <linux/netlink.h>
12 #include <linux/openvswitch.h>
13 #include <linux/spinlock.h>
14 #include <linux/types.h>
15 #include <linux/rcupdate.h>
16 #include <linux/if_ether.h>
17 #include <linux/in6.h>
18 #include <linux/jiffies.h>
19 #include <linux/time.h>
20 #include <linux/cpumask.h>
21 #include <net/inet_ecn.h>
22 #include <net/ip_tunnels.h>
23 #include <net/dst_metadata.h>
24 #include <net/nsh.h>
25 
26 struct sk_buff;
27 
28 enum sw_flow_mac_proto {
29 	MAC_PROTO_NONE = 0,
30 	MAC_PROTO_ETHERNET,
31 };
32 #define SW_FLOW_KEY_INVALID	0x80
33 
34 /* Store options at the end of the array if they are less than the
35  * maximum size. This allows us to get the benefits of variable length
36  * matching for small options.
37  */
38 #define TUN_METADATA_OFFSET(opt_len) \
39 	(FIELD_SIZEOF(struct sw_flow_key, tun_opts) - opt_len)
40 #define TUN_METADATA_OPTS(flow_key, opt_len) \
41 	((void *)((flow_key)->tun_opts + TUN_METADATA_OFFSET(opt_len)))
42 
43 struct ovs_tunnel_info {
44 	struct metadata_dst	*tun_dst;
45 };
46 
47 struct vlan_head {
48 	__be16 tpid; /* Vlan type. Generally 802.1q or 802.1ad.*/
49 	__be16 tci;  /* 0 if no VLAN, VLAN_CFI_MASK set otherwise. */
50 };
51 
52 #define OVS_SW_FLOW_KEY_METADATA_SIZE			\
53 	(offsetof(struct sw_flow_key, recirc_id) +	\
54 	FIELD_SIZEOF(struct sw_flow_key, recirc_id))
55 
56 struct ovs_key_nsh {
57 	struct ovs_nsh_key_base base;
58 	__be32 context[NSH_MD1_CONTEXT_SIZE];
59 };
60 
61 struct sw_flow_key {
62 	u8 tun_opts[IP_TUNNEL_OPTS_MAX];
63 	u8 tun_opts_len;
64 	struct ip_tunnel_key tun_key;	/* Encapsulating tunnel key. */
65 	struct {
66 		u32	priority;	/* Packet QoS priority. */
67 		u32	skb_mark;	/* SKB mark. */
68 		u16	in_port;	/* Input switch port (or DP_MAX_PORTS). */
69 	} __packed phy; /* Safe when right after 'tun_key'. */
70 	u8 mac_proto;			/* MAC layer protocol (e.g. Ethernet). */
71 	u8 tun_proto;			/* Protocol of encapsulating tunnel. */
72 	u32 ovs_flow_hash;		/* Datapath computed hash value.  */
73 	u32 recirc_id;			/* Recirculation ID.  */
74 	struct {
75 		u8     src[ETH_ALEN];	/* Ethernet source address. */
76 		u8     dst[ETH_ALEN];	/* Ethernet destination address. */
77 		struct vlan_head vlan;
78 		struct vlan_head cvlan;
79 		__be16 type;		/* Ethernet frame type. */
80 	} eth;
81 	/* Filling a hole of two bytes. */
82 	u8 ct_state;
83 	u8 ct_orig_proto;		/* CT original direction tuple IP
84 					 * protocol.
85 					 */
86 	union {
87 		struct {
88 			__be32 top_lse;	/* top label stack entry */
89 		} mpls;
90 		struct {
91 			u8     proto;	/* IP protocol or lower 8 bits of ARP opcode. */
92 			u8     tos;	    /* IP ToS. */
93 			u8     ttl;	    /* IP TTL/hop limit. */
94 			u8     frag;	/* One of OVS_FRAG_TYPE_*. */
95 		} ip;
96 	};
97 	u16 ct_zone;			/* Conntrack zone. */
98 	struct {
99 		__be16 src;		/* TCP/UDP/SCTP source port. */
100 		__be16 dst;		/* TCP/UDP/SCTP destination port. */
101 		__be16 flags;		/* TCP flags. */
102 	} tp;
103 	union {
104 		struct {
105 			struct {
106 				__be32 src;	/* IP source address. */
107 				__be32 dst;	/* IP destination address. */
108 			} addr;
109 			union {
110 				struct {
111 					__be32 src;
112 					__be32 dst;
113 				} ct_orig;	/* Conntrack original direction fields. */
114 				struct {
115 					u8 sha[ETH_ALEN];	/* ARP source hardware address. */
116 					u8 tha[ETH_ALEN];	/* ARP target hardware address. */
117 				} arp;
118 			};
119 		} ipv4;
120 		struct {
121 			struct {
122 				struct in6_addr src;	/* IPv6 source address. */
123 				struct in6_addr dst;	/* IPv6 destination address. */
124 			} addr;
125 			__be32 label;			/* IPv6 flow label. */
126 			union {
127 				struct {
128 					struct in6_addr src;
129 					struct in6_addr dst;
130 				} ct_orig;	/* Conntrack original direction fields. */
131 				struct {
132 					struct in6_addr target;	/* ND target address. */
133 					u8 sll[ETH_ALEN];	/* ND source link layer address. */
134 					u8 tll[ETH_ALEN];	/* ND target link layer address. */
135 				} nd;
136 			};
137 		} ipv6;
138 		struct ovs_key_nsh nsh;         /* network service header */
139 	};
140 	struct {
141 		/* Connection tracking fields not packed above. */
142 		struct {
143 			__be16 src;	/* CT orig tuple tp src port. */
144 			__be16 dst;	/* CT orig tuple tp dst port. */
145 		} orig_tp;
146 		u32 mark;
147 		struct ovs_key_ct_labels labels;
148 	} ct;
149 
150 } __aligned(BITS_PER_LONG/8); /* Ensure that we can do comparisons as longs. */
151 
152 static inline bool sw_flow_key_is_nd(const struct sw_flow_key *key)
153 {
154 	return key->eth.type == htons(ETH_P_IPV6) &&
155 		key->ip.proto == NEXTHDR_ICMP &&
156 		key->tp.dst == 0 &&
157 		(key->tp.src == htons(NDISC_NEIGHBOUR_SOLICITATION) ||
158 		 key->tp.src == htons(NDISC_NEIGHBOUR_ADVERTISEMENT));
159 }
160 
161 struct sw_flow_key_range {
162 	unsigned short int start;
163 	unsigned short int end;
164 };
165 
166 struct sw_flow_mask {
167 	int ref_count;
168 	struct rcu_head rcu;
169 	struct list_head list;
170 	struct sw_flow_key_range range;
171 	struct sw_flow_key key;
172 };
173 
174 struct sw_flow_match {
175 	struct sw_flow_key *key;
176 	struct sw_flow_key_range range;
177 	struct sw_flow_mask *mask;
178 };
179 
180 #define MAX_UFID_LENGTH 16 /* 128 bits */
181 
182 struct sw_flow_id {
183 	u32 ufid_len;
184 	union {
185 		u32 ufid[MAX_UFID_LENGTH / 4];
186 		struct sw_flow_key *unmasked_key;
187 	};
188 };
189 
190 struct sw_flow_actions {
191 	struct rcu_head rcu;
192 	size_t orig_len;	/* From flow_cmd_new netlink actions size */
193 	u32 actions_len;
194 	struct nlattr actions[];
195 };
196 
197 struct flow_stats {
198 	u64 packet_count;		/* Number of packets matched. */
199 	u64 byte_count;			/* Number of bytes matched. */
200 	unsigned long used;		/* Last used time (in jiffies). */
201 	spinlock_t lock;		/* Lock for atomic stats update. */
202 	__be16 tcp_flags;		/* Union of seen TCP flags. */
203 };
204 
205 struct sw_flow {
206 	struct rcu_head rcu;
207 	struct {
208 		struct hlist_node node[2];
209 		u32 hash;
210 	} flow_table, ufid_table;
211 	int stats_last_writer;		/* CPU id of the last writer on
212 					 * 'stats[0]'.
213 					 */
214 	struct sw_flow_key key;
215 	struct sw_flow_id id;
216 	struct cpumask cpu_used_mask;
217 	struct sw_flow_mask *mask;
218 	struct sw_flow_actions __rcu *sf_acts;
219 	struct flow_stats __rcu *stats[]; /* One for each CPU.  First one
220 					   * is allocated at flow creation time,
221 					   * the rest are allocated on demand
222 					   * while holding the 'stats[0].lock'.
223 					   */
224 };
225 
226 struct arp_eth_header {
227 	__be16      ar_hrd;	/* format of hardware address   */
228 	__be16      ar_pro;	/* format of protocol address   */
229 	unsigned char   ar_hln;	/* length of hardware address   */
230 	unsigned char   ar_pln;	/* length of protocol address   */
231 	__be16      ar_op;	/* ARP opcode (command)     */
232 
233 	/* Ethernet+IPv4 specific members. */
234 	unsigned char       ar_sha[ETH_ALEN];	/* sender hardware address  */
235 	unsigned char       ar_sip[4];		/* sender IP address        */
236 	unsigned char       ar_tha[ETH_ALEN];	/* target hardware address  */
237 	unsigned char       ar_tip[4];		/* target IP address        */
238 } __packed;
239 
240 static inline u8 ovs_key_mac_proto(const struct sw_flow_key *key)
241 {
242 	return key->mac_proto & ~SW_FLOW_KEY_INVALID;
243 }
244 
245 static inline u16 __ovs_mac_header_len(u8 mac_proto)
246 {
247 	return mac_proto == MAC_PROTO_ETHERNET ? ETH_HLEN : 0;
248 }
249 
250 static inline u16 ovs_mac_header_len(const struct sw_flow_key *key)
251 {
252 	return __ovs_mac_header_len(ovs_key_mac_proto(key));
253 }
254 
255 static inline bool ovs_identifier_is_ufid(const struct sw_flow_id *sfid)
256 {
257 	return sfid->ufid_len;
258 }
259 
260 static inline bool ovs_identifier_is_key(const struct sw_flow_id *sfid)
261 {
262 	return !ovs_identifier_is_ufid(sfid);
263 }
264 
265 void ovs_flow_stats_update(struct sw_flow *, __be16 tcp_flags,
266 			   const struct sk_buff *);
267 void ovs_flow_stats_get(const struct sw_flow *, struct ovs_flow_stats *,
268 			unsigned long *used, __be16 *tcp_flags);
269 void ovs_flow_stats_clear(struct sw_flow *);
270 u64 ovs_flow_used_time(unsigned long flow_jiffies);
271 
272 int ovs_flow_key_update(struct sk_buff *skb, struct sw_flow_key *key);
273 int ovs_flow_key_extract(const struct ip_tunnel_info *tun_info,
274 			 struct sk_buff *skb,
275 			 struct sw_flow_key *key);
276 /* Extract key from packet coming from userspace. */
277 int ovs_flow_key_extract_userspace(struct net *net, const struct nlattr *attr,
278 				   struct sk_buff *skb,
279 				   struct sw_flow_key *key, bool log);
280 
281 #endif /* flow.h */
282