lib/meta-flow.h

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