lib/meta-flow.h

   1 /*
   2  * Copyright (c) 2011, 2012, 2013 Nicira, Inc.
   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 "ofp-errors.h"
  25 #include "packets.h"
  26
  27 struct ds;
  28 struct match;
  29
  30 /* The comment on each of these indicates the member in "union mf_value" used
  31  * to represent its value. */
  32 enum mf_field_id {
  33     /* Metadata. */
  34     MFF_TUN_ID,                 /* be64 */
  35     MFF_TUN_SRC,                /* be32 */
  36     MFF_TUN_DST,                /* be32 */
  37     MFF_TUN_FLAGS,              /* be16 */
  38     MFF_TUN_TTL,                /* u8 */
  39     MFF_TUN_TOS,                /* u8 */
  40     MFF_METADATA,               /* be64 */
  41     MFF_IN_PORT,                /* be16 */
  42     MFF_IN_PORT_OXM,            /* be32 */
  43     MFF_SKB_PRIORITY,           /* be32 */
  44     MFF_SKB_MARK,               /* be32 */
  45
  46 #if FLOW_N_REGS > 0
  47     MFF_REG0,                   /* be32 */
  48 #endif
  49 #if FLOW_N_REGS > 1
  50     MFF_REG1,                   /* be32 */
  51 #endif
  52 #if FLOW_N_REGS > 2
  53     MFF_REG2,                   /* be32 */
  54 #endif
  55 #if FLOW_N_REGS > 3
  56     MFF_REG3,                   /* be32 */
  57 #endif
  58 #if FLOW_N_REGS > 4
  59     MFF_REG4,                   /* be32 */
  60 #endif
  61 #if FLOW_N_REGS > 5
  62     MFF_REG5,                   /* be32 */
  63 #endif
  64 #if FLOW_N_REGS > 6
  65     MFF_REG6,                   /* be32 */
  66 #endif
  67 #if FLOW_N_REGS > 7
  68     MFF_REG7,                   /* be32 */
  69 #endif
  70
  71     /* L2. */
  72     MFF_ETH_SRC,                /* mac */
  73     MFF_ETH_DST,                /* mac */
  74     MFF_ETH_TYPE,               /* be16 */
  75
  76     MFF_VLAN_TCI,               /* be16 */
  77     MFF_DL_VLAN,                /* be16 (OpenFlow 1.0 compatibility) */
  78     MFF_VLAN_VID,               /* be16 (OpenFlow 1.2 compatibility) */
  79     MFF_DL_VLAN_PCP,            /* u8 (OpenFlow 1.0 compatibility) */
  80     MFF_VLAN_PCP,               /* be16 (OpenFlow 1.2 compatibility) */
  81
  82     /* L2.5 */
  83     MFF_MPLS_LABEL,             /* be32 */
  84     MFF_MPLS_TC,                /* u8 */
  85     MFF_MPLS_BOS,               /* u8 */
  86
  87     /* L3. */
  88     MFF_IPV4_SRC,               /* be32 */
  89     MFF_IPV4_DST,               /* be32 */
  90
  91     MFF_IPV6_SRC,               /* ipv6 */
  92     MFF_IPV6_DST,               /* ipv6 */
  93     MFF_IPV6_LABEL,             /* be32 */
  94
  95     /* The IPv4/IPv6 DSCP field has two different views:
  96      *
  97      *   - MFF_IP_DSCP has the DSCP in bits 2-7, their bit positions in the
  98      *     IPv4 and IPv6 "traffic class" field, as used in OpenFlow 1.0 and 1.1
  99      *     flow format and in NXM's NXM_OF_IP_TOS
 100      *
 101      *   - MFF_IP_DSCP has the DSCP in bits 0-5, shifted right two bits from
 102      *     their positions in the IPv4 and IPv6 "traffic class" field, as used
 103      *     in OpenFlow 1.2+ OXM's OXM_OF_IP_DSCP. */
 104     MFF_IP_PROTO,               /* u8 (used for IPv4 or IPv6) */
 105     MFF_IP_DSCP,                /* u8 (used for IPv4 or IPv6) */
 106     MFF_IP_DSCP_SHIFTED,        /* u8 (used for IPv4 or IPv6) (OF1.2 compat) */
 107     MFF_IP_ECN,                 /* u8 (used for IPv4 or IPv6) */
 108     MFF_IP_TTL,                 /* u8 (used for IPv4 or IPv6) */
 109     MFF_IP_FRAG,                /* u8 (used for IPv4 or IPv6) */
 110
 111     MFF_ARP_OP,                 /* be16 */
 112     MFF_ARP_SPA,                /* be32 */
 113     MFF_ARP_TPA,                /* be32 */
 114     MFF_ARP_SHA,                /* mac */
 115     MFF_ARP_THA,                /* mac */
 116
 117     /* L4. */
 118     MFF_TCP_SRC,                /* be16 (used for IPv4 or IPv6) */
 119     MFF_TCP_DST,                /* be16 (used for IPv4 or IPv6) */
 120
 121     MFF_UDP_SRC,                /* be16 (used for IPv4 or IPv6) */
 122     MFF_UDP_DST,                /* be16 (used for IPv4 or IPv6) */
 123
 124     MFF_ICMPV4_TYPE,            /* u8 */
 125     MFF_ICMPV4_CODE,            /* u8 */
 126
 127     MFF_ICMPV6_TYPE,            /* u8 */
 128     MFF_ICMPV6_CODE,            /* u8 */
 129
 130     /* ICMPv6 Neighbor Discovery. */
 131     MFF_ND_TARGET,              /* ipv6 */
 132     MFF_ND_SLL,                 /* mac */
 133     MFF_ND_TLL,                 /* mac */
 134
 135     MFF_N_IDS
 136 };
 137
 138 /* Use this macro as CASE_MFF_REGS: in a switch statement to choose all of the
 139  * MFF_REGx cases. */
 140 #if FLOW_N_REGS == 1
 141 # define CASE_MFF_REGS                                          \
 142     case MFF_REG0
 143 #elif FLOW_N_REGS == 2
 144 # define CASE_MFF_REGS                                          \
 145     case MFF_REG0: case MFF_REG1
 146 #elif FLOW_N_REGS == 3
 147 # define CASE_MFF_REGS                                          \
 148     case MFF_REG0: case MFF_REG1: case MFF_REG2
 149 #elif FLOW_N_REGS == 4
 150 # define CASE_MFF_REGS                                          \
 151     case MFF_REG0: case MFF_REG1: case MFF_REG2: case MFF_REG3
 152 #elif FLOW_N_REGS == 5
 153 # define CASE_MFF_REGS                                          \
 154     case MFF_REG0: case MFF_REG1: case MFF_REG2: case MFF_REG3: \
 155     case MFF_REG4
 156 #elif FLOW_N_REGS == 6
 157 # define CASE_MFF_REGS                                          \
 158     case MFF_REG0: case MFF_REG1: case MFF_REG2: case MFF_REG3: \
 159     case MFF_REG4: case MFF_REG5
 160 #elif FLOW_N_REGS == 7
 161 # define CASE_MFF_REGS                                          \
 162     case MFF_REG0: case MFF_REG1: case MFF_REG2: case MFF_REG3: \
 163     case MFF_REG4: case MFF_REG5: case MFF_REG6
 164 #elif FLOW_N_REGS == 8
 165 # define CASE_MFF_REGS                                          \
 166     case MFF_REG0: case MFF_REG1: case MFF_REG2: case MFF_REG3: \
 167     case MFF_REG4: case MFF_REG5: case MFF_REG6: case MFF_REG7
 168 #else
 169 # error
 170 #endif
 171
 172 /* Prerequisites for matching a field.
 173  *
 174  * A field may only be matched if the correct lower-level protocols are also
 175  * matched.  For example, the TCP port may be matched only if the Ethernet type
 176  * matches ETH_TYPE_IP and the IP protocol matches IPPROTO_TCP. */
 177 enum mf_prereqs {
 178     MFP_NONE,
 179
 180     /* L2 requirements. */
 181     MFP_ARP,
 182     MFP_VLAN_VID,
 183     MFP_IPV4,
 184     MFP_IPV6,
 185     MFP_IP_ANY,
 186
 187     /* L2.5 requirements. */
 188     MFP_MPLS,
 189
 190     /* L2+L3 requirements. */
 191     MFP_TCP,                    /* On IPv4 or IPv6. */
 192     MFP_UDP,                    /* On IPv4 or IPv6. */
 193     MFP_ICMPV4,
 194     MFP_ICMPV6,
 195
 196     /* L2+L3+L4 requirements. */
 197     MFP_ND,
 198     MFP_ND_SOLICIT,
 199     MFP_ND_ADVERT
 200 };
 201
 202 /* Forms of partial-field masking allowed for a field.
 203  *
 204  * Every field may be masked as a whole. */
 205 enum mf_maskable {
 206     MFM_NONE,                   /* No sub-field masking. */
 207     MFM_FULLY,                  /* Every bit is individually maskable. */
 208 };
 209
 210 /* How to format or parse a field's value. */
 211 enum mf_string {
 212     /* Integer formats.
 213      *
 214      * The particular MFS_* constant sets the output format.  On input, either
 215      * decimal or hexadecimal (prefixed with 0x) is accepted. */
 216     MFS_DECIMAL,
 217     MFS_HEXADECIMAL,
 218
 219     /* Other formats. */
 220     MFS_ETHERNET,
 221     MFS_IPV4,
 222     MFS_IPV6,
 223     MFS_OFP_PORT,               /* An OpenFlow port number or name. */
 224     MFS_OFP_PORT_OXM,           /* An OpenFlow port number or name (32-bit). */
 225     MFS_FRAG,                   /* no, yes, first, later, not_later */
 226     MFS_TNL_FLAGS,              /* FLOW_TNL_F_* flags */
 227 };
 228
 229 struct mf_field {
 230     /* Identification. */
 231     enum mf_field_id id;        /* MFF_*. */
 232     const char *name;           /* Name of this field, e.g. "eth_type". */
 233     const char *extra_name;     /* Alternate name, e.g. "dl_type", or NULL. */
 234
 235     /* Size.
 236      *
 237      * Most fields have n_bytes * 8 == n_bits.  There are a few exceptions:
 238      *
 239      *     - "dl_vlan" is 2 bytes but only 12 bits.
 240      *     - "dl_vlan_pcp" is 1 byte but only 3 bits.
 241      *     - "is_frag" is 1 byte but only 2 bits.
 242      *     - "ipv6_label" is 4 bytes but only 20 bits.
 243      *     - "mpls_label" is 4 bytes but only 20 bits.
 244      *     - "mpls_tc"    is 1 byte but only 3 bits.
 245      *     - "mpls_bos"   is 1 byte but only 1 bit.
 246      */
 247     unsigned int n_bytes;       /* Width of the field in bytes. */
 248     unsigned int n_bits;        /* Number of significant bits in field. */
 249
 250     /* Properties. */
 251     enum mf_maskable maskable;
 252     enum mf_string string;
 253     enum mf_prereqs prereqs;
 254     bool writable;              /* May be written by actions? */
 255
 256     /* NXM and OXM properties.
 257      *
 258      * There are the following possibilities for these members for a given
 259      * mf_field:
 260      *
 261      *   - Neither NXM nor OXM defines such a field: these members will all be
 262      *     zero or NULL.
 263      *
 264      *   - NXM and OXM both define such a field: nxm_header and oxm_header will
 265      *     both be nonzero and different, similarly for nxm_name and oxm_name.
 266      *
 267      *   - Only NXM or only OXM defines such a field: nxm_header and oxm_header
 268      *     will both have the same value (either an OXM_* or NXM_* value) and
 269      *     similarly for nxm_name and oxm_name.
 270      *
 271      * Thus, 'nxm_header' is the appropriate header to use when outputting an
 272      * NXM formatted match, since it will be an NXM_* constant when possible
 273      * for compatibility with OpenFlow implementations that expect that, with
 274      * OXM_* constants used for fields that OXM adds.  Conversely, 'oxm_header'
 275      * is the header to use when outputting an OXM formatted match. */
 276     uint32_t nxm_header;        /* An NXM_* (or OXM_*) constant. */
 277     const char *nxm_name;       /* The nxm_header constant's name. */
 278     uint32_t oxm_header;        /* An OXM_* (or NXM_*) constant. */
 279     const char *oxm_name;           /* The oxm_header constant's name */
 280 };
 281
 282 /* The representation of a field's value. */
 283 union mf_value {
 284     uint8_t u8;
 285     ovs_be16 be16;
 286     ovs_be32 be32;
 287     ovs_be64 be64;
 288     uint8_t mac[ETH_ADDR_LEN];
 289     struct in6_addr ipv6;
 290 };
 291 BUILD_ASSERT_DECL(sizeof(union mf_value) == 16);
 292
 293 /* Part of a field. */
 294 struct mf_subfield {
 295     const struct mf_field *field;
 296     unsigned int ofs;           /* Bit offset. */
 297     unsigned int n_bits;        /* Number of bits. */
 298 };
 299
 300 /* Data for some part of an mf_field.
 301  *
 302  * The data is stored "right-justified".  For example, if "union mf_subvalue
 303  * value" contains NXM_OF_VLAN_TCI[0..11], then one could access the
 304  * corresponding data in value.be16[7] as the bits in the mask htons(0xfff). */
 305 union mf_subvalue {
 306     uint8_t u8[16];
 307     ovs_be16 be16[8];
 308     ovs_be32 be32[4];
 309     ovs_be64 be64[2];
 310 };
 311 BUILD_ASSERT_DECL(sizeof(union mf_value) == sizeof (union mf_subvalue));
 312
 313 /* Finding mf_fields. */
 314 const struct mf_field *mf_from_id(enum mf_field_id);
 315 const struct mf_field *mf_from_name(const char *name);
 316 const struct mf_field *mf_from_nxm_header(uint32_t nxm_header);
 317 const struct mf_field *mf_from_nxm_name(const char *nxm_name);
 318
 319 /* Inspecting wildcarded bits. */
 320 bool mf_is_all_wild(const struct mf_field *, const struct flow_wildcards *);
 321
 322 bool mf_is_mask_valid(const struct mf_field *, const union mf_value *mask);
 323 void mf_get_mask(const struct mf_field *, const struct flow_wildcards *,
 324                  union mf_value *mask);
 325
 326 /* Prerequisites. */
 327 bool mf_are_prereqs_ok(const struct mf_field *, const struct flow *);
 328 void mf_force_prereqs(const struct mf_field *, struct match *);
 329
 330 /* Field values. */
 331 bool mf_is_value_valid(const struct mf_field *, const union mf_value *value);
 332
 333 void mf_get_value(const struct mf_field *, const struct flow *,
 334                   union mf_value *value);
 335 void mf_set_value(const struct mf_field *, const union mf_value *value,
 336                   struct match *);
 337 void mf_set_flow_value(const struct mf_field *, const union mf_value *value,
 338                        struct flow *);
 339 bool mf_is_zero(const struct mf_field *, const struct flow *);
 340
 341 void mf_get(const struct mf_field *, const struct match *,
 342             union mf_value *value, union mf_value *mask);
 343 void mf_set(const struct mf_field *,
 344             const union mf_value *value, const union mf_value *mask,
 345             struct match *);
 346
 347 void mf_set_wild(const struct mf_field *, struct match *);
 348
 349 void mf_random_value(const struct mf_field *, union mf_value *value);
 350
 351 /* Subfields. */
 352 void mf_write_subfield_flow(const struct mf_subfield *,
 353                             const union mf_subvalue *, struct flow *);
 354 void mf_write_subfield(const struct mf_subfield *, const union mf_subvalue *,
 355                        struct match *);
 356
 357 void mf_read_subfield(const struct mf_subfield *, const struct flow *,
 358                       union mf_subvalue *);
 359 uint64_t mf_get_subfield(const struct mf_subfield *, const struct flow *);
 360
 361
 362 void mf_format_subfield(const struct mf_subfield *, struct ds *);
 363 char *mf_parse_subfield__(struct mf_subfield *sf, const char **s)
 364     WARN_UNUSED_RESULT;
 365 char *mf_parse_subfield(struct mf_subfield *, const char *s)
 366     WARN_UNUSED_RESULT;
 367
 368 enum ofperr mf_check_src(const struct mf_subfield *, const struct flow *);
 369 enum ofperr mf_check_dst(const struct mf_subfield *, const struct flow *);
 370
 371 /* Parsing and formatting. */
 372 char *mf_parse(const struct mf_field *, const char *,
 373                union mf_value *value, union mf_value *mask);
 374 char *mf_parse_value(const struct mf_field *, const char *, union mf_value *);
 375 void mf_format(const struct mf_field *,
 376                const union mf_value *value, const union mf_value *mask,
 377                struct ds *);
 378 void mf_format_subvalue(const union mf_subvalue *subvalue, struct ds *s);
 379
 380 #endif /* meta-flow.h */