lib/flow.h

   1 /*
   2  * Copyright (c) 2008, 2009, 2010 Nicira Networks.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at:
   7  *
   8  *     http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16 #ifndef FLOW_H
  17 #define FLOW_H 1
  18
  19 #include <sys/types.h>
  20 #include <netinet/in.h>
  21 #include <stdbool.h>
  22 #include <stdint.h>
  23 #include <string.h>
  24 #include "openflow/nicira-ext.h"
  25 #include "openflow/openflow.h"
  26 #include "hash.h"
  27 #include "openvswitch/datapath-protocol.h"
  28 #include "util.h"
  29
  30 struct ds;
  31 struct ofp_match;
  32 struct ofpbuf;
  33
  34 struct flow {
  35     ovs_be32 tun_id;            /* Encapsulating tunnel ID. */
  36     ovs_be32 nw_src;            /* IP source address. */
  37     ovs_be32 nw_dst;            /* IP destination address. */
  38     uint16_t in_port;           /* Input switch port. */
  39     ovs_be16 dl_vlan;           /* Input VLAN. */
  40     ovs_be16 dl_type;           /* Ethernet frame type. */
  41     ovs_be16 tp_src;            /* TCP/UDP source port. */
  42     ovs_be16 tp_dst;            /* TCP/UDP destination port. */
  43     uint8_t dl_src[6];          /* Ethernet source address. */
  44     uint8_t dl_dst[6];          /* Ethernet destination address. */
  45     uint8_t nw_proto;           /* IP protocol or low 8 bits of ARP opcode. */
  46     uint8_t dl_vlan_pcp;        /* Input VLAN priority. */
  47     uint8_t nw_tos;             /* IP ToS (DSCP field, 6 bits). */
  48 };
  49
  50 /* Assert that there are FLOW_SIG_SIZE bytes of significant data in "struct
  51  * flow", followed by FLOW_PAD_SIZE bytes of padding. */
  52 #define FLOW_SIG_SIZE 37
  53 #define FLOW_PAD_SIZE 3
  54 BUILD_ASSERT_DECL(offsetof(struct flow, nw_tos) == FLOW_SIG_SIZE - 1);
  55 BUILD_ASSERT_DECL(sizeof(((struct flow *)0)->nw_tos) == 1);
  56 BUILD_ASSERT_DECL(sizeof(struct flow) == FLOW_SIG_SIZE + FLOW_PAD_SIZE);
  57
  58 int flow_extract(struct ofpbuf *, ovs_be32 tun_id, uint16_t in_port,
  59                  struct flow *);
  60 void flow_extract_stats(const struct flow *flow, struct ofpbuf *packet,
  61         struct odp_flow_stats *stats);
  62 void flow_to_match(const struct flow *, uint32_t wildcards, bool tun_id_cookie,
  63                    struct ofp_match *);
  64 void flow_from_match(const struct ofp_match *, bool tun_id_from_cookie,
  65                      ovs_be64 cookie, struct flow *, uint32_t *wildcards);
  66 char *flow_to_string(const struct flow *);
  67 void flow_format(struct ds *, const struct flow *);
  68 void flow_print(FILE *, const struct flow *);
  69 static inline int flow_compare(const struct flow *, const struct flow *);
  70 static inline bool flow_equal(const struct flow *, const struct flow *);
  71 static inline size_t flow_hash(const struct flow *, uint32_t basis);
  72
  73 static inline int
  74 flow_compare(const struct flow *a, const struct flow *b)
  75 {
  76     return memcmp(a, b, FLOW_SIG_SIZE);
  77 }
  78
  79 static inline bool
  80 flow_equal(const struct flow *a, const struct flow *b)
  81 {
  82     return !flow_compare(a, b);
  83 }
  84
  85 static inline size_t
  86 flow_hash(const struct flow *flow, uint32_t basis)
  87 {
  88     return hash_bytes(flow, FLOW_SIG_SIZE, basis);
  89 }
  90
  91 /* Information on wildcards for a flow, as a supplement to "struct flow".
  92  *
  93  * The flow_wildcards_*() functions below both depend on and maintain the
  94  * following important invariants:
  95  *
  96  * 1. 'wildcards' is nonzero if and only if at least one bit or field is
  97  *    wildcarded.
  98  *
  99  * 2. Bits in 'wildcards' not included in OVSFW_ALL are set to 0.  (This is a
 100  *    corollary to invariant #1.)
 101  *
 102  * 3. The fields in 'wildcards' masked by OFPFW_NW_SRC_MASK and
 103  *    OFPFW_NW_DST_MASK have values between 0 and 32, inclusive.
 104  *
 105  * 4. The fields masked by OFPFW_NW_SRC_MASK and OFPFW_NW_DST_MASK correspond
 106  *    correctly to the masks in 'nw_src_mask' and 'nw_dst_mask', respectively.
 107  */
 108 struct flow_wildcards {
 109     uint32_t wildcards;         /* enum ofp_flow_wildcards. */
 110     ovs_be32 nw_src_mask;       /* 1-bit in each significant nw_src bit. */
 111     ovs_be32 nw_dst_mask;       /* 1-bit in each significant nw_dst bit. */
 112 };
 113
 114 ovs_be32 flow_nw_bits_to_mask(uint32_t wildcards, int shift);
 115 void flow_wildcards_init(struct flow_wildcards *, uint32_t wildcards);
 116 void flow_wildcards_init_exact(struct flow_wildcards *);
 117
 118 bool flow_wildcards_set_nw_src_mask(struct flow_wildcards *, ovs_be32);
 119 bool flow_wildcards_set_nw_dst_mask(struct flow_wildcards *, ovs_be32);
 120
 121 void flow_wildcards_combine(struct flow_wildcards *dst,
 122                             const struct flow_wildcards *src1,
 123                             const struct flow_wildcards *src2);
 124 bool flow_wildcards_has_extra(const struct flow_wildcards *,
 125                               const struct flow_wildcards *);
 126
 127 uint32_t flow_wildcards_hash(const struct flow_wildcards *);
 128 bool flow_wildcards_equal(const struct flow_wildcards *,
 129                           const struct flow_wildcards *);
 130
 131 #endif /* flow.h */