lib/flow.h

   1 /*
   2  * Copyright (c) 2008, 2009, 2010, 2011 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 "util.h"
  28
  29 struct dpif_flow_stats;
  30 struct ds;
  31 struct flow_wildcards;
  32 struct ofp_match;
  33 struct ofpbuf;
  34
  35 /* This sequence number should be incremented whenever anything involving flows
  36  * or the wildcarding of flows changes.  This will cause build assertion
  37  * failures in places which likely need to be updated. */
  38 #define FLOW_WC_SEQ 7
  39
  40 #define FLOW_N_REGS 5
  41 BUILD_ASSERT_DECL(FLOW_N_REGS <= NXM_NX_MAX_REGS);
  42
  43 /* Used for struct flow's dl_type member for frames that have no Ethernet
  44  * type, that is, pure 802.2 frames. */
  45 #define FLOW_DL_TYPE_NONE 0x5ff
  46
  47 /* Fragment bits, used for IPv4 and IPv6, always zero for non-IP flows. */
  48 #define FLOW_NW_FRAG_ANY   (1 << 0) /* Set for any IP frag. */
  49 #define FLOW_NW_FRAG_LATER (1 << 1) /* Set for IP frag with nonzero offset. */
  50 #define FLOW_NW_FRAG_MASK  (FLOW_NW_FRAG_ANY | FLOW_NW_FRAG_LATER)
  51
  52 BUILD_ASSERT_DECL(FLOW_NW_FRAG_ANY == NX_IP_FRAG_ANY);
  53 BUILD_ASSERT_DECL(FLOW_NW_FRAG_LATER == NX_IP_FRAG_LATER);
  54
  55 struct flow {
  56     ovs_be64 tun_id;            /* Encapsulating tunnel ID. */
  57     struct in6_addr ipv6_src;   /* IPv6 source address. */
  58     struct in6_addr ipv6_dst;   /* IPv6 destination address. */
  59     struct in6_addr nd_target;  /* IPv6 neighbor discovery (ND) target. */
  60     uint32_t priority;          /* Packet priority for QoS. */
  61     uint32_t regs[FLOW_N_REGS]; /* Registers. */
  62     ovs_be32 nw_src;            /* IPv4 source address. */
  63     ovs_be32 nw_dst;            /* IPv4 destination address. */
  64     ovs_be32 ipv6_label;        /* IPv6 flow label. */
  65     uint16_t in_port;           /* OpenFlow port number of input port. */
  66     ovs_be16 vlan_tci;          /* If 802.1Q, TCI | VLAN_CFI; otherwise 0. */
  67     ovs_be16 dl_type;           /* Ethernet frame type. */
  68     ovs_be16 tp_src;            /* TCP/UDP source port. */
  69     ovs_be16 tp_dst;            /* TCP/UDP destination port. */
  70     uint8_t dl_src[6];          /* Ethernet source address. */
  71     uint8_t dl_dst[6];          /* Ethernet destination address. */
  72     uint8_t nw_proto;           /* IP protocol or low 8 bits of ARP opcode. */
  73     uint8_t nw_tos;             /* IP ToS (including DSCP and ECN). */
  74     uint8_t arp_sha[6];         /* ARP/ND source hardware address. */
  75     uint8_t arp_tha[6];         /* ARP/ND target hardware address. */
  76     uint8_t nw_ttl;             /* IP TTL/Hop Limit. */
  77     uint8_t nw_frag;            /* FLOW_FRAG_* flags. */
  78     uint8_t reserved[6];        /* Reserved for 64-bit packing. */
  79 };
  80
  81 /* Assert that there are FLOW_SIG_SIZE bytes of significant data in "struct
  82  * flow", followed by FLOW_PAD_SIZE bytes of padding. */
  83 #define FLOW_SIG_SIZE (110 + FLOW_N_REGS * 4)
  84 #define FLOW_PAD_SIZE 6
  85 BUILD_ASSERT_DECL(offsetof(struct flow, nw_frag) == FLOW_SIG_SIZE - 1);
  86 BUILD_ASSERT_DECL(sizeof(((struct flow *)0)->nw_frag) == 1);
  87 BUILD_ASSERT_DECL(sizeof(struct flow) == FLOW_SIG_SIZE + FLOW_PAD_SIZE);
  88
  89 /* Remember to update FLOW_WC_SEQ when changing 'struct flow'. */
  90 BUILD_ASSERT_DECL(FLOW_SIG_SIZE == 130 && FLOW_WC_SEQ == 7);
  91
  92 void flow_extract(struct ofpbuf *, uint32_t priority, ovs_be64 tun_id,
  93                   uint16_t in_port, struct flow *);
  94 void flow_zero_wildcards(struct flow *, const struct flow_wildcards *);
  95
  96 char *flow_to_string(const struct flow *);
  97 void flow_format(struct ds *, const struct flow *);
  98 void flow_print(FILE *, const struct flow *);
  99 static inline int flow_compare_3way(const struct flow *, const struct flow *);
 100 static inline bool flow_equal(const struct flow *, const struct flow *);
 101 static inline size_t flow_hash(const struct flow *, uint32_t basis);
 102
 103 void flow_set_vlan_vid(struct flow *, ovs_be16 vid);
 104 void flow_set_vlan_pcp(struct flow *, uint8_t pcp);
 105
 106 void flow_compose(struct ofpbuf *, const struct flow *);
 107
 108 static inline int
 109 flow_compare_3way(const struct flow *a, const struct flow *b)
 110 {
 111     return memcmp(a, b, FLOW_SIG_SIZE);
 112 }
 113
 114 static inline bool
 115 flow_equal(const struct flow *a, const struct flow *b)
 116 {
 117     return !flow_compare_3way(a, b);
 118 }
 119
 120 static inline size_t
 121 flow_hash(const struct flow *flow, uint32_t basis)
 122 {
 123     return hash_bytes(flow, FLOW_SIG_SIZE, basis);
 124 }
 125
 126 /* Open vSwitch flow wildcard bits.
 127  *
 128  * These are used only internally to Open vSwitch, in the 'wildcards' member of
 129  * struct flow_wildcards.  They never appear in the wire protocol in this
 130  * form. */
 131
 132 typedef unsigned int OVS_BITWISE flow_wildcards_t;
 133
 134 /* Same values and meanings as corresponding OFPFW_* bits. */
 135 #define FWW_IN_PORT     ((OVS_FORCE flow_wildcards_t) (1 << 0))
 136 #define FWW_DL_SRC      ((OVS_FORCE flow_wildcards_t) (1 << 2))
 137 #define FWW_DL_DST      ((OVS_FORCE flow_wildcards_t) (1 << 3))
 138                                               /* excluding the multicast bit */
 139 #define FWW_DL_TYPE     ((OVS_FORCE flow_wildcards_t) (1 << 4))
 140 #define FWW_NW_PROTO    ((OVS_FORCE flow_wildcards_t) (1 << 5))
 141 #define FWW_TP_SRC      ((OVS_FORCE flow_wildcards_t) (1 << 6))
 142 #define FWW_TP_DST      ((OVS_FORCE flow_wildcards_t) (1 << 7))
 143 /* No corresponding OFPFW_* bits. */
 144 #define FWW_ETH_MCAST   ((OVS_FORCE flow_wildcards_t) (1 << 1))
 145                                                        /* multicast bit only */
 146 #define FWW_ARP_SHA     ((OVS_FORCE flow_wildcards_t) (1 << 8))
 147 #define FWW_ARP_THA     ((OVS_FORCE flow_wildcards_t) (1 << 9))
 148 #define FWW_ND_TARGET   ((OVS_FORCE flow_wildcards_t) (1 << 10))
 149 #define FWW_IPV6_LABEL  ((OVS_FORCE flow_wildcards_t) (1 << 11))
 150 #define FWW_NW_TTL      ((OVS_FORCE flow_wildcards_t) (1 << 12))
 151 #define FWW_NW_DSCP     ((OVS_FORCE flow_wildcards_t) (1 << 13))
 152 #define FWW_NW_ECN      ((OVS_FORCE flow_wildcards_t) (1 << 14))
 153 #define FWW_ALL         ((OVS_FORCE flow_wildcards_t) (((1 << 15)) - 1))
 154
 155 /* Remember to update FLOW_WC_SEQ when adding or removing FWW_*. */
 156 BUILD_ASSERT_DECL(FWW_ALL == ((1 << 15) - 1) && FLOW_WC_SEQ == 7);
 157
 158 /* Information on wildcards for a flow, as a supplement to "struct flow".
 159  *
 160  * Note that the meaning of 1-bits in 'wildcards' is opposite that of 1-bits in
 161  * the rest of the members. */
 162 struct flow_wildcards {
 163     ovs_be64 tun_id_mask;       /* 1-bit in each significant tun_id bit. */
 164     flow_wildcards_t wildcards; /* 1-bit in each FWW_* wildcarded field. */
 165     uint32_t reg_masks[FLOW_N_REGS]; /* 1-bit in each significant regs bit. */
 166     ovs_be32 nw_src_mask;       /* 1-bit in each significant nw_src bit. */
 167     ovs_be32 nw_dst_mask;       /* 1-bit in each significant nw_dst bit. */
 168     struct in6_addr ipv6_src_mask; /* 1-bit in each signficant ipv6_src bit. */
 169     struct in6_addr ipv6_dst_mask; /* 1-bit in each signficant ipv6_dst bit. */
 170     ovs_be16 vlan_tci_mask;     /* 1-bit in each significant vlan_tci bit. */
 171     uint8_t nw_frag_mask;       /* 1-bit in each significant nw_frag bit. */
 172     uint8_t zeros[5];           /* Padding field set to zero. */
 173 };
 174
 175 /* Remember to update FLOW_WC_SEQ when updating struct flow_wildcards. */
 176 BUILD_ASSERT_DECL(sizeof(struct flow_wildcards) == 80 && FLOW_WC_SEQ == 7);
 177
 178 void flow_wildcards_init_catchall(struct flow_wildcards *);
 179 void flow_wildcards_init_exact(struct flow_wildcards *);
 180
 181 bool flow_wildcards_is_exact(const struct flow_wildcards *);
 182 bool flow_wildcards_is_catchall(const struct flow_wildcards *);
 183
 184 void flow_wildcards_set_reg_mask(struct flow_wildcards *,
 185                                  int idx, uint32_t mask);
 186
 187 void flow_wildcards_combine(struct flow_wildcards *dst,
 188                             const struct flow_wildcards *src1,
 189                             const struct flow_wildcards *src2);
 190 bool flow_wildcards_has_extra(const struct flow_wildcards *,
 191                               const struct flow_wildcards *);
 192
 193 uint32_t flow_wildcards_hash(const struct flow_wildcards *, uint32_t basis);
 194 bool flow_wildcards_equal(const struct flow_wildcards *,
 195                           const struct flow_wildcards *);
 196 uint32_t flow_hash_symmetric_l4(const struct flow *flow, uint32_t basis);
 197
 198 const uint8_t *flow_wildcards_to_dl_dst_mask(flow_wildcards_t);
 199 bool flow_wildcards_is_dl_dst_mask_valid(const uint8_t[6]);
 200 flow_wildcards_t flow_wildcards_set_dl_dst_mask(flow_wildcards_t,
 201                                                 const uint8_t mask[6]);
 202 uint32_t flow_hash_fields(const struct flow *, enum nx_hash_fields,
 203                           uint16_t basis);
 204 const char *flow_hash_fields_to_str(enum nx_hash_fields);
 205 bool flow_hash_fields_valid(enum nx_hash_fields);
 206
 207 #endif /* flow.h */