1 /*
2  * Copyright (c) 2007-2011 Nicira Networks.
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of version 2 of the GNU General Public
6  * License as published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope that it will be useful, but
9  * WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11  * General Public License for more details.
12  *
13  * You should have received a copy of the GNU General Public License
14  * along with this program; if not, write to the Free Software
15  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
16  * 02110-1301, USA
17  */
18 
19 #ifndef FLOW_H
20 #define FLOW_H 1
21 
22 #include <linux/kernel.h>
23 #include <linux/netlink.h>
24 #include <linux/openvswitch.h>
25 #include <linux/spinlock.h>
26 #include <linux/types.h>
27 #include <linux/rcupdate.h>
28 #include <linux/if_ether.h>
29 #include <linux/in6.h>
30 #include <linux/jiffies.h>
31 #include <linux/time.h>
32 #include <linux/flex_array.h>
33 #include <net/inet_ecn.h>
34 
35 struct sk_buff;
36 
37 struct sw_flow_actions {
38 	struct rcu_head rcu;
39 	u32 actions_len;
40 	struct nlattr actions[];
41 };
42 
43 struct sw_flow_key {
44 	struct {
45 		u32	priority;	/* Packet QoS priority. */
46 		u16	in_port;	/* Input switch port (or USHRT_MAX). */
47 	} phy;
48 	struct {
49 		u8     src[ETH_ALEN];	/* Ethernet source address. */
50 		u8     dst[ETH_ALEN];	/* Ethernet destination address. */
51 		__be16 tci;		/* 0 if no VLAN, VLAN_TAG_PRESENT set otherwise. */
52 		__be16 type;		/* Ethernet frame type. */
53 	} eth;
54 	struct {
55 		u8     proto;		/* IP protocol or lower 8 bits of ARP opcode. */
56 		u8     tos;		/* IP ToS. */
57 		u8     ttl;		/* IP TTL/hop limit. */
58 		u8     frag;		/* One of OVS_FRAG_TYPE_*. */
59 	} ip;
60 	union {
61 		struct {
62 			struct {
63 				__be32 src;	/* IP source address. */
64 				__be32 dst;	/* IP destination address. */
65 			} addr;
66 			union {
67 				struct {
68 					__be16 src;		/* TCP/UDP source port. */
69 					__be16 dst;		/* TCP/UDP destination port. */
70 				} tp;
71 				struct {
72 					u8 sha[ETH_ALEN];	/* ARP source hardware address. */
73 					u8 tha[ETH_ALEN];	/* ARP target hardware address. */
74 				} arp;
75 			};
76 		} ipv4;
77 		struct {
78 			struct {
79 				struct in6_addr src;	/* IPv6 source address. */
80 				struct in6_addr dst;	/* IPv6 destination address. */
81 			} addr;
82 			__be32 label;			/* IPv6 flow label. */
83 			struct {
84 				__be16 src;		/* TCP/UDP source port. */
85 				__be16 dst;		/* TCP/UDP destination port. */
86 			} tp;
87 			struct {
88 				struct in6_addr target;	/* ND target address. */
89 				u8 sll[ETH_ALEN];	/* ND source link layer address. */
90 				u8 tll[ETH_ALEN];	/* ND target link layer address. */
91 			} nd;
92 		} ipv6;
93 	};
94 };
95 
96 struct sw_flow {
97 	struct rcu_head rcu;
98 	struct hlist_node hash_node[2];
99 	u32 hash;
100 
101 	struct sw_flow_key key;
102 	struct sw_flow_actions __rcu *sf_acts;
103 
104 	spinlock_t lock;	/* Lock for values below. */
105 	unsigned long used;	/* Last used time (in jiffies). */
106 	u64 packet_count;	/* Number of packets matched. */
107 	u64 byte_count;		/* Number of bytes matched. */
108 	u8 tcp_flags;		/* Union of seen TCP flags. */
109 };
110 
111 struct arp_eth_header {
112 	__be16      ar_hrd;	/* format of hardware address   */
113 	__be16      ar_pro;	/* format of protocol address   */
114 	unsigned char   ar_hln;	/* length of hardware address   */
115 	unsigned char   ar_pln;	/* length of protocol address   */
116 	__be16      ar_op;	/* ARP opcode (command)     */
117 
118 	/* Ethernet+IPv4 specific members. */
119 	unsigned char       ar_sha[ETH_ALEN];	/* sender hardware address  */
120 	unsigned char       ar_sip[4];		/* sender IP address        */
121 	unsigned char       ar_tha[ETH_ALEN];	/* target hardware address  */
122 	unsigned char       ar_tip[4];		/* target IP address        */
123 } __packed;
124 
125 int ovs_flow_init(void);
126 void ovs_flow_exit(void);
127 
128 struct sw_flow *ovs_flow_alloc(void);
129 void ovs_flow_deferred_free(struct sw_flow *);
130 void ovs_flow_free(struct sw_flow *flow);
131 
132 struct sw_flow_actions *ovs_flow_actions_alloc(const struct nlattr *);
133 void ovs_flow_deferred_free_acts(struct sw_flow_actions *);
134 
135 int ovs_flow_extract(struct sk_buff *, u16 in_port, struct sw_flow_key *,
136 		     int *key_lenp);
137 void ovs_flow_used(struct sw_flow *, struct sk_buff *);
138 u64 ovs_flow_used_time(unsigned long flow_jiffies);
139 
140 /* Upper bound on the length of a nlattr-formatted flow key.  The longest
141  * nlattr-formatted flow key would be:
142  *
143  *                         struct  pad  nl hdr  total
144  *                         ------  ---  ------  -----
145  *  OVS_KEY_ATTR_PRIORITY      4    --     4      8
146  *  OVS_KEY_ATTR_IN_PORT       4    --     4      8
147  *  OVS_KEY_ATTR_ETHERNET     12    --     4     16
148  *  OVS_KEY_ATTR_8021Q         4    --     4      8
149  *  OVS_KEY_ATTR_ETHERTYPE     2     2     4      8
150  *  OVS_KEY_ATTR_IPV6         40    --     4     44
151  *  OVS_KEY_ATTR_ICMPV6        2     2     4      8
152  *  OVS_KEY_ATTR_ND           28    --     4     32
153  *  -------------------------------------------------
154  *  total                                       132
155  */
156 #define FLOW_BUFSIZE 132
157 
158 int ovs_flow_to_nlattrs(const struct sw_flow_key *, struct sk_buff *);
159 int ovs_flow_from_nlattrs(struct sw_flow_key *swkey, int *key_lenp,
160 		      const struct nlattr *);
161 int ovs_flow_metadata_from_nlattrs(u32 *priority, u16 *in_port,
162 			       const struct nlattr *);
163 
164 #define TBL_MIN_BUCKETS		1024
165 
166 struct flow_table {
167 	struct flex_array *buckets;
168 	unsigned int count, n_buckets;
169 	struct rcu_head rcu;
170 	int node_ver;
171 	u32 hash_seed;
172 	bool keep_flows;
173 };
174 
ovs_flow_tbl_count(struct flow_table * table)175 static inline int ovs_flow_tbl_count(struct flow_table *table)
176 {
177 	return table->count;
178 }
179 
ovs_flow_tbl_need_to_expand(struct flow_table * table)180 static inline int ovs_flow_tbl_need_to_expand(struct flow_table *table)
181 {
182 	return (table->count > table->n_buckets);
183 }
184 
185 struct sw_flow *ovs_flow_tbl_lookup(struct flow_table *table,
186 				    struct sw_flow_key *key, int len);
187 void ovs_flow_tbl_destroy(struct flow_table *table);
188 void ovs_flow_tbl_deferred_destroy(struct flow_table *table);
189 struct flow_table *ovs_flow_tbl_alloc(int new_size);
190 struct flow_table *ovs_flow_tbl_expand(struct flow_table *table);
191 struct flow_table *ovs_flow_tbl_rehash(struct flow_table *table);
192 void ovs_flow_tbl_insert(struct flow_table *table, struct sw_flow *flow);
193 void ovs_flow_tbl_remove(struct flow_table *table, struct sw_flow *flow);
194 u32 ovs_flow_hash(const struct sw_flow_key *key, int key_len);
195 
196 struct sw_flow *ovs_flow_tbl_next(struct flow_table *table, u32 *bucket, u32 *idx);
197 extern const int ovs_key_lens[OVS_KEY_ATTR_MAX + 1];
198 
199 #endif /* flow.h */
200