lib/meta-flow.h

   1 /*
   2  * Copyright (c) 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
  17 #ifndef META_FLOW_H
  18 #define META_FLOW_H 1
  19
  20 #include <sys/types.h>
  21 #include <netinet/in.h>
  22 #include <netinet/ip6.h>
  23 #include "flow.h"
  24 #include "packets.h"
  25
  26 struct cls_rule;
  27 struct ds;
  28
  29 /* The comment on each of these indicates the member in "union mf_value" used
  30  * to represent its value. */
  31 enum mf_field_id {
  32     /* Metadata. */
  33     MFF_TUN_ID,                 /* be64 */
  34     MFF_IN_PORT,                /* be16 */
  35
  36 #if FLOW_N_REGS > 0
  37     MFF_REG0,                   /* be32 */
  38 #endif
  39 #if FLOW_N_REGS > 1
  40     MFF_REG1,                   /* be32 */
  41 #endif
  42 #if FLOW_N_REGS > 2
  43     MFF_REG2,                   /* be32 */
  44 #endif
  45 #if FLOW_N_REGS > 3
  46     MFF_REG3,                   /* be32 */
  47 #endif
  48 #if FLOW_N_REGS > 4
  49     MFF_REG4,                   /* be32 */
  50 #endif
  51 #if FLOW_N_REGS > 5
  52 #error
  53 #endif
  54
  55     /* L2. */
  56     MFF_ETH_SRC,                /* mac */
  57     MFF_ETH_DST,                /* mac */
  58     MFF_ETH_TYPE,               /* be16 */
  59
  60     MFF_VLAN_TCI,               /* be16 */
  61     MFF_VLAN_VID,               /* be16 */
  62     MFF_VLAN_PCP,               /* u8 */
  63
  64     /* L3. */
  65     MFF_IPV4_SRC,               /* be32 */
  66     MFF_IPV4_DST,               /* be32 */
  67
  68     MFF_IPV6_SRC,               /* ipv6 */
  69     MFF_IPV6_DST,               /* ipv6 */
  70     MFF_IPV6_LABEL,             /* be32 */
  71
  72     MFF_IP_PROTO,               /* u8 (used for IPv4 or IPv6) */
  73     MFF_IP_DSCP,                /* u8 (used for IPv4 or IPv6) */
  74     MFF_IP_ECN,                 /* u8 (used for IPv4 or IPv6) */
  75     MFF_IP_TTL,                 /* u8 (used for IPv4 or IPv6) */
  76     MFF_IP_FRAG,                /* u8 (used for IPv4 or IPv6) */
  77
  78     MFF_ARP_OP,                 /* be16 */
  79     MFF_ARP_SPA,                /* be32 */
  80     MFF_ARP_TPA,                /* be32 */
  81     MFF_ARP_SHA,                /* mac */
  82     MFF_ARP_THA,                /* mac */
  83
  84     /* L4. */
  85     MFF_TCP_SRC,                /* be16 (used for IPv4 or IPv6) */
  86     MFF_TCP_DST,                /* be16 (used for IPv4 or IPv6) */
  87
  88     MFF_UDP_SRC,                /* be16 (used for IPv4 or IPv6) */
  89     MFF_UDP_DST,                /* be16 (used for IPv4 or IPv6) */
  90
  91     MFF_ICMPV4_TYPE,            /* u8 */
  92     MFF_ICMPV4_CODE,            /* u8 */
  93
  94     MFF_ICMPV6_TYPE,            /* u8 */
  95     MFF_ICMPV6_CODE,            /* u8 */
  96
  97     /* ICMPv6 Neighbor Discovery. */
  98     MFF_ND_TARGET,              /* ipv6 */
  99     MFF_ND_SLL,                 /* mac */
 100     MFF_ND_TLL,                 /* mac */
 101
 102     MFF_N_IDS
 103 };
 104
 105 /* Prerequisites for matching a field.
 106  *
 107  * A field may only be matched if the correct lower-level protocols are also
 108  * matched.  For example, the TCP port may be matched only if the Ethernet type
 109  * matches ETH_TYPE_IP and the IP protocol matches IPPROTO_TCP. */
 110 enum mf_prereqs {
 111     MFP_NONE,
 112
 113     /* L2 requirements. */
 114     MFP_ARP,
 115     MFP_IPV4,
 116     MFP_IPV6,
 117     MFP_IP_ANY,
 118
 119     /* L2+L3 requirements. */
 120     MFP_TCP,                    /* On IPv4 or IPv6. */
 121     MFP_UDP,                    /* On IPv4 or IPv6. */
 122     MFP_ICMPV4,
 123     MFP_ICMPV6,
 124
 125     /* L2+L3+L4 requirements. */
 126     MFP_ND,
 127     MFP_ND_SOLICIT,
 128     MFP_ND_ADVERT
 129 };
 130
 131 /* Forms of partial-field masking allowed for a field.
 132  *
 133  * Every field may be masked as a whole. */
 134 enum mf_maskable {
 135     MFM_NONE,                   /* No sub-field masking. */
 136     MFM_FULLY,                  /* Every bit is individually maskable. */
 137     MFM_CIDR,                   /* Contiguous low-order bits may be masked. */
 138     MFM_MCAST                   /* Byte 0, bit 0 is separately maskable. */
 139 };
 140
 141 /* How to format or parse a field's value. */
 142 enum mf_string {
 143     /* Integer formats.
 144      *
 145      * The particular MFS_* constant sets the output format.  On input, either
 146      * decimal or hexadecimal (prefixed with 0x) is accepted. */
 147     MFS_DECIMAL,
 148     MFS_HEXADECIMAL,
 149
 150     /* Other formats. */
 151     MFS_ETHERNET,
 152     MFS_IPV4,
 153     MFS_IPV6,
 154     MFS_OFP_PORT,               /* An OpenFlow port number or name. */
 155     MFS_FRAG                    /* no, yes, first, later, not_later */
 156 };
 157
 158 struct mf_field {
 159     /* Identification. */
 160     enum mf_field_id id;        /* MFF_*. */
 161     const char *name;           /* Name of this field, e.g. "eth_type". */
 162     const char *extra_name;     /* Alternate name, e.g. "dl_type", or NULL. */
 163
 164     /* Size.
 165      *
 166      * Most fields have n_bytes * 8 == n_bits.  There are a few exceptions:
 167      *
 168      *     - "dl_vlan" is 2 bytes but only 12 bits.
 169      *     - "dl_vlan_pcp" is 1 byte but only 3 bits.
 170      *     - "is_frag" is 1 byte but only 2 bits.
 171      *     - "ipv6_label" is 4 bytes but only 20 bits.
 172      */
 173     unsigned int n_bytes;       /* Width of the field in bytes. */
 174     unsigned int n_bits;        /* Number of significant bits in field. */
 175
 176     /* Properties. */
 177     enum mf_maskable maskable;
 178     flow_wildcards_t fww_bit;   /* Either 0 or exactly one FWW_* bit. */
 179     enum mf_string string;
 180     enum mf_prereqs prereqs;
 181     bool writable;              /* May be written by actions? */
 182
 183     /* NXM properties.
 184      *
 185      * A few "mf_field"s don't correspond to NXM fields.  Those have 0 and
 186      * NULL for the following members, respectively. */
 187     uint32_t nxm_header;        /* An NXM_* constant (a few fields have 0). */
 188     const char *nxm_name;       /* The "NXM_*" constant's name. */
 189 };
 190
 191 /* The representation of a field's value. */
 192 union mf_value {
 193     uint8_t u8;
 194     ovs_be16 be16;
 195     ovs_be32 be32;
 196     ovs_be64 be64;
 197     uint8_t mac[ETH_ADDR_LEN];
 198     struct in6_addr ipv6;
 199 };
 200
 201 /* Finding mf_fields. */
 202 const struct mf_field *mf_from_id(enum mf_field_id);
 203 const struct mf_field *mf_from_name(const char *name);
 204 const struct mf_field *mf_from_nxm_header(uint32_t nxm_header);
 205 const struct mf_field *mf_from_nxm_name(const char *nxm_name);
 206
 207 /* Inspecting wildcarded bits. */
 208 bool mf_is_all_wild(const struct mf_field *, const struct flow_wildcards *);
 209
 210 bool mf_is_mask_valid(const struct mf_field *, const union mf_value *mask);
 211 void mf_get_mask(const struct mf_field *, const struct flow_wildcards *,
 212                  union mf_value *mask);
 213
 214 /* Prerequisites. */
 215 bool mf_are_prereqs_ok(const struct mf_field *, const struct flow *);
 216 void mf_force_prereqs(const struct mf_field *, struct cls_rule *);
 217
 218 /* Field values. */
 219 bool mf_is_value_valid(const struct mf_field *, const union mf_value *value);
 220
 221 void mf_get_value(const struct mf_field *, const struct flow *,
 222                   union mf_value *value);
 223 void mf_set_value(const struct mf_field *, const union mf_value *value,
 224                   struct cls_rule *);
 225 void mf_set_flow_value(const struct mf_field *, const union mf_value *value,
 226                        struct flow *);
 227
 228 void mf_get(const struct mf_field *, const struct cls_rule *,
 229             union mf_value *value, union mf_value *mask);
 230 void mf_set(const struct mf_field *,
 231             const union mf_value *value, const union mf_value *mask,
 232             struct cls_rule *);
 233 void mf_set_subfield(const struct mf_field *, uint64_t value, unsigned int ofs,
 234                      unsigned int n_bits, struct cls_rule *);
 235
 236 void mf_set_wild(const struct mf_field *, struct cls_rule *);
 237
 238 void mf_random_value(const struct mf_field *, union mf_value *value);
 239
 240 /* Parsing and formatting. */
 241 char *mf_parse(const struct mf_field *, const char *,
 242                union mf_value *value, union mf_value *mask);
 243 char *mf_parse_value(const struct mf_field *, const char *, union mf_value *);
 244 void mf_format(const struct mf_field *,
 245                const union mf_value *value, const union mf_value *mask,
 246                struct ds *);
 247
 248 #endif /* meta-flow.h */