summaryrefslogtreecommitdiff
path: root/lib/classifier.h
blob: a632fb02452b7b71459e3ddd277a8d9d04d8833f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
/*
 * Copyright (c) 2009 Nicira Networks.
 *
 * Permission to use, copy, modify, and/or distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#ifndef CLASSIFIER_H
#define CLASSIFIER_H 1

/* Flow classifier.
 *
 * This flow classifier assumes that we can arrange the fields in a flow in an
 * order such that the set of wildcarded fields in a rule tend to fall toward
 * the end of the ordering.  That is, if field F is wildcarded, then all the
 * fields after F tend to be wildcarded as well.  If this assumption is
 * violated, then the classifier will still classify flows correctly, but its
 * performance will suffer.
 */

#include "flow.h"
#include "hmap.h"
#include "list.h"
#include "openflow/openflow.h"

/* Number of bytes of fields in a rule. */
#define CLS_N_BYTES 31

/* Fields in a rule.
 *
 * This definition sets the ordering of fields, which is important for
 * performance (see above).  To adjust the ordering, change the order of the
 * lines. */
#define CLS_FIELDS                                          \
    /*                           flow_t       all-caps */   \
    /*        wildcard bit(s)    member name  name     */   \
    /*        -----------------  -----------  -------- */   \
    CLS_FIELD(OFPFW_IN_PORT,     in_port,     IN_PORT)      \
    CLS_FIELD(OFPFW_DL_VLAN,     dl_vlan,     DL_VLAN)      \
    CLS_FIELD(OFPFW_DL_SRC,      dl_src,      DL_SRC)       \
    CLS_FIELD(OFPFW_DL_DST,      dl_dst,      DL_DST)       \
    CLS_FIELD(OFPFW_DL_TYPE,     dl_type,     DL_TYPE)      \
    CLS_FIELD(OFPFW_NW_SRC_MASK, nw_src,      NW_SRC)       \
    CLS_FIELD(OFPFW_NW_DST_MASK, nw_dst,      NW_DST)       \
    CLS_FIELD(OFPFW_NW_PROTO,    nw_proto,    NW_PROTO)     \
    CLS_FIELD(OFPFW_TP_SRC,      tp_src,      TP_SRC)       \
    CLS_FIELD(OFPFW_TP_DST,      tp_dst,      TP_DST)

/* Field indexes.
 *
 * (These are also indexed into struct classifier's 'tables' array.) */
enum {
#define CLS_FIELD(WILDCARDS, MEMBER, NAME) CLS_F_IDX_##NAME,
    CLS_FIELDS
#undef CLS_FIELD
    CLS_F_IDX_EXACT,            /* Exact-match table. */
    CLS_N_FIELDS = CLS_F_IDX_EXACT
};

/* Field information. */
struct cls_field {
    int ofs;                    /* Offset in flow_t. */
    int len;                    /* Length in bytes. */
    uint32_t wildcards;         /* OFPFW_* bit or bits for this field. */
    const char *name;           /* Name (for debugging). */
};
extern const struct cls_field cls_fields[CLS_N_FIELDS + 1];

/* A flow classifier. */
struct classifier {
    int n_rules;                /* Sum of hmap_count() over tables[]. */
    struct hmap tables[CLS_N_FIELDS]; /* Contain cls_bucket elements. */
    struct hmap exact_table;          /* Contain cls_rule elements. */
};

/* A group of rules with the same fixed values for initial fields. */
struct cls_bucket {
    struct hmap_node hmap_node; /* Within struct classifier 'tables'. */
    struct list rules;          /* In order from highest to lowest priority. */
    flow_t fixed;               /* Values for fixed fields. */
};

/* A flow classification rule.
 *
 * Use cls_rule_from_flow() or cls_rule_from_match() to initialize a cls_rule
 * or you will almost certainly not initialize 'table_idx' correctly, with
 * disastrous results! */
struct cls_rule {
    union {
        struct list list;       /* Within struct cls_bucket 'rules'. */
        struct hmap_node hmap;  /* Within struct classifier 'exact_table'. */
    } node;
    flow_t flow;                /* All field values. */
    struct flow_wildcards wc;   /* Wildcards for fields. */
    unsigned int priority;      /* Larger numbers are higher priorities. */
    unsigned int table_idx;     /* Index into struct classifier 'tables'. */
};

void cls_rule_from_flow(struct cls_rule *, const flow_t *, uint32_t wildcards,
                        unsigned int priority);
void cls_rule_from_match(struct cls_rule *, const struct ofp_match *,
                         unsigned int priority);
void cls_rule_print(const struct cls_rule *);
void cls_rule_moved(struct classifier *,
                    struct cls_rule *old, struct cls_rule *new);
void cls_rule_replace(struct classifier *, const struct cls_rule *old,
                      struct cls_rule *new);

void classifier_init(struct classifier *);
void classifier_destroy(struct classifier *);
bool classifier_is_empty(const struct classifier *);
int classifier_count(const struct classifier *);
int classifier_count_exact(const struct classifier *);
struct cls_rule *classifier_insert(struct classifier *, struct cls_rule *);
void classifier_insert_exact(struct classifier *, struct cls_rule *);
void classifier_remove(struct classifier *, struct cls_rule *);
struct cls_rule *classifier_lookup(const struct classifier *, const flow_t *);
struct cls_rule *classifier_lookup_wild(const struct classifier *,
                                        const flow_t *);
struct cls_rule *classifier_lookup_exact(const struct classifier *,
                                         const flow_t *);

typedef void cls_cb_func(struct cls_rule *, void *aux);

enum {
    CLS_INC_EXACT = 1 << 0,     /* Include exact-match flows? */
    CLS_INC_WILD = 1 << 1,      /* Include flows with wildcards? */
    CLS_INC_ALL = CLS_INC_EXACT | CLS_INC_WILD
};
void classifier_for_each(const struct classifier *, int include,
                         cls_cb_func *, void *aux);
void classifier_for_each_match(const struct classifier *,
                               const struct cls_rule *,
                               int include, cls_cb_func *, void *aux);
struct cls_rule *classifier_find_rule_exactly(const struct classifier *,
                                              const flow_t *target,
                                              uint32_t wildcards,
                                              unsigned int priority);

#endif /* classifier.h */