lib/ofp-actions.h

   1 /*
   2  * Copyright (c) 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 OFP_ACTIONS_H
  18 #define OFP_ACTIONS_H 1
  19
  20 #include <stdint.h>
  21 #include "meta-flow.h"
  22 #include "ofp-errors.h"
  23 #include "ofp-util.h"
  24 #include "openflow/openflow.h"
  25 #include "openflow/nicira-ext.h"
  26 #include "openvswitch/types.h"
  27
  28 /* List of OVS abstracted actions.
  29  *
  30  * This macro is used directly only internally by this header, but the list is
  31  * still of interest to developers.
  32  *
  33  * Each DEFINE_OFPACT invocation has the following parameters:
  34  *
  35  * 1. <ENUM>, used below in the enum definition of OFPACT_<ENUM>, and
  36  *    elsewhere.
  37  *
  38  * 2. <STRUCT> corresponding to a structure "struct <STRUCT>", that must be
  39  *    defined below.  This structure must be an abstract definition of the
  40  *    action.  Its first member must have type "struct ofpact" and name
  41  *    "ofpact".  It may be fixed length or end with a flexible array member
  42  *    (e.g. "int member[];").
  43  *
  44  * 3. <MEMBER>, which has one of two possible values:
  45  *
  46  *        - If "struct <STRUCT>" is fixed-length, it must be "ofpact".
  47  *
  48  *        - If "struct <STRUCT>" is variable-length, it must be the name of the
  49  *          flexible array member.
  50  */
  51 #define OFPACTS                                                     \
  52     /* Output. */                                                   \
  53     DEFINE_OFPACT(OUTPUT,          ofpact_output,        ofpact)    \
  54     DEFINE_OFPACT(CONTROLLER,      ofpact_controller,    ofpact)    \
  55     DEFINE_OFPACT(ENQUEUE,         ofpact_enqueue,       ofpact)    \
  56     DEFINE_OFPACT(OUTPUT_REG,      ofpact_output_reg,    ofpact)    \
  57     DEFINE_OFPACT(BUNDLE,          ofpact_bundle,        slaves)    \
  58                                                                     \
  59     /* Header changes. */                                           \
  60     DEFINE_OFPACT(SET_VLAN_VID,    ofpact_vlan_vid,      ofpact)    \
  61     DEFINE_OFPACT(SET_VLAN_PCP,    ofpact_vlan_pcp,      ofpact)    \
  62     DEFINE_OFPACT(STRIP_VLAN,      ofpact_null,          ofpact)    \
  63     DEFINE_OFPACT(PUSH_VLAN,       ofpact_null,          ofpact)    \
  64     DEFINE_OFPACT(SET_ETH_SRC,     ofpact_mac,           ofpact)    \
  65     DEFINE_OFPACT(SET_ETH_DST,     ofpact_mac,           ofpact)    \
  66     DEFINE_OFPACT(SET_IPV4_SRC,    ofpact_ipv4,          ofpact)    \
  67     DEFINE_OFPACT(SET_IPV4_DST,    ofpact_ipv4,          ofpact)    \
  68     DEFINE_OFPACT(SET_IPV4_DSCP,   ofpact_dscp,          ofpact)    \
  69     DEFINE_OFPACT(SET_L4_SRC_PORT, ofpact_l4_port,       ofpact)    \
  70     DEFINE_OFPACT(SET_L4_DST_PORT, ofpact_l4_port,       ofpact)    \
  71     DEFINE_OFPACT(REG_MOVE,        ofpact_reg_move,      ofpact)    \
  72     DEFINE_OFPACT(REG_LOAD,        ofpact_reg_load,      ofpact)    \
  73     DEFINE_OFPACT(STACK_PUSH,      ofpact_stack,         ofpact)    \
  74     DEFINE_OFPACT(STACK_POP,       ofpact_stack,         ofpact)    \
  75     DEFINE_OFPACT(DEC_TTL,         ofpact_cnt_ids,       cnt_ids)   \
  76     DEFINE_OFPACT(SET_MPLS_TTL,    ofpact_mpls_ttl,      ofpact)    \
  77     DEFINE_OFPACT(DEC_MPLS_TTL,    ofpact_null,          ofpact)    \
  78     DEFINE_OFPACT(PUSH_MPLS,       ofpact_push_mpls,     ofpact)    \
  79     DEFINE_OFPACT(POP_MPLS,        ofpact_pop_mpls,      ofpact)    \
  80                                                                     \
  81     /* Metadata. */                                                 \
  82     DEFINE_OFPACT(SET_TUNNEL,      ofpact_tunnel,        ofpact)    \
  83     DEFINE_OFPACT(SET_QUEUE,       ofpact_queue,         ofpact)    \
  84     DEFINE_OFPACT(POP_QUEUE,       ofpact_null,          ofpact)    \
  85     DEFINE_OFPACT(FIN_TIMEOUT,     ofpact_fin_timeout,   ofpact)    \
  86                                                                     \
  87     /* Flow table interaction. */                                   \
  88     DEFINE_OFPACT(RESUBMIT,        ofpact_resubmit,      ofpact)    \
  89     DEFINE_OFPACT(LEARN,           ofpact_learn,         specs)     \
  90                                                                     \
  91     /* Arithmetic. */                                               \
  92     DEFINE_OFPACT(MULTIPATH,       ofpact_multipath,     ofpact)    \
  93                                                                     \
  94     /* Other. */                                                    \
  95     DEFINE_OFPACT(NOTE,            ofpact_note,          data)      \
  96     DEFINE_OFPACT(EXIT,            ofpact_null,          ofpact)    \
  97     DEFINE_OFPACT(SAMPLE,          ofpact_sample,        ofpact)    \
  98                                                                     \
  99     /* Instructions */                                              \
 100     DEFINE_OFPACT(METER,           ofpact_meter,         ofpact)    \
 101     /* XXX Write-Actions */                                         \
 102     DEFINE_OFPACT(CLEAR_ACTIONS,   ofpact_null,          ofpact)    \
 103     DEFINE_OFPACT(WRITE_METADATA,  ofpact_metadata,      ofpact)    \
 104     DEFINE_OFPACT(GOTO_TABLE,      ofpact_goto_table,    ofpact)
 105
 106 /* enum ofpact_type, with a member OFPACT_<ENUM> for each action. */
 107 enum OVS_PACKED_ENUM ofpact_type {
 108 #define DEFINE_OFPACT(ENUM, STRUCT, MEMBER) OFPACT_##ENUM,
 109     OFPACTS
 110 #undef DEFINE_OFPACT
 111 };
 112
 113 /* N_OFPACTS, the number of values of "enum ofpact_type". */
 114 enum {
 115     N_OFPACTS =
 116 #define DEFINE_OFPACT(ENUM, STRUCT, MEMBER) + 1
 117     OFPACTS
 118 #undef DEFINE_OFPACT
 119 };
 120
 121 /* Header for an action.
 122  *
 123  * Each action is a structure "struct ofpact_*" that begins with "struct
 124  * ofpact", usually followed by other data that describes the action.  Actions
 125  * are padded out to a multiple of OFPACT_ALIGNTO bytes in length.
 126  *
 127  * The 'compat' member is special:
 128  *
 129  *     - Most "struct ofpact"s correspond to one particular kind of OpenFlow
 130  *       action, at least in a given OpenFlow version.  For example,
 131  *       OFPACT_SET_VLAN_VID corresponds to OFPAT10_SET_VLAN_VID in OpenFlow
 132  *       1.0.
 133  *
 134  *       For such actions, the 'compat' member is not meaningful and generally
 135  *       should be zero.
 136  *
 137  *     - A few "struct ofpact"s correspond to multiple OpenFlow actions.  For
 138  *       example, OFPACT_SET_TUNNEL can be NXAST_SET_TUNNEL or
 139  *       NXAST_SET_TUNNEL64.  In these cases, if the "struct ofpact" originated
 140  *       from OpenFlow, then we want to make sure that, if it gets translated
 141  *       back to OpenFlow later, it is translated back to the same action type.
 142  *       (Otherwise, we'd violate the promise made in DESIGN, in the "Action
 143  *       Reproduction" section.)
 144  *
 145  *       For such actions, the 'compat' member should be the original action
 146  *       type.  (If the action didn't originate from OpenFlow, then setting
 147  *       'compat' to zero should be fine: code to translate the ofpact to
 148  *       OpenFlow must tolerate this case.)
 149  */
 150 struct ofpact {
 151     enum ofpact_type type;      /* OFPACT_*. */
 152     enum ofputil_action_code compat; /* Original type when added, if any. */
 153     uint16_t len;               /* Length of the action, in bytes, including
 154                                  * struct ofpact, excluding padding. */
 155 };
 156
 157 #ifdef __GNUC__
 158 /* Make sure that OVS_PACKED_ENUM really worked. */
 159 BUILD_ASSERT_DECL(sizeof(struct ofpact) == 4);
 160 #endif
 161
 162 /* Alignment. */
 163 #define OFPACT_ALIGNTO 8
 164 #define OFPACT_ALIGN(SIZE) ROUND_UP(SIZE, OFPACT_ALIGNTO)
 165
 166 static inline struct ofpact *
 167 ofpact_next(const struct ofpact *ofpact)
 168 {
 169     return (void *) ((uint8_t *) ofpact + OFPACT_ALIGN(ofpact->len));
 170 }
 171
 172 static inline struct ofpact *
 173 ofpact_end(const struct ofpact *ofpacts, size_t ofpacts_len)
 174 {
 175     return (void *) ((uint8_t *) ofpacts + ofpacts_len);
 176 }
 177
 178 /* Assigns POS to each ofpact, in turn, in the OFPACTS_LEN bytes of ofpacts
 179  * starting at OFPACTS. */
 180 #define OFPACT_FOR_EACH(POS, OFPACTS, OFPACTS_LEN)                      \
 181     for ((POS) = (OFPACTS); (POS) < ofpact_end(OFPACTS, OFPACTS_LEN);  \
 182          (POS) = ofpact_next(POS))
 183 \f
 184 /* Action structure for each OFPACT_*. */
 185
 186 /* OFPACT_STRIP_VLAN, OFPACT_POP_QUEUE, OFPACT_EXIT, OFPACT_CLEAR_ACTIONS.
 187  *
 188  * Used for OFPAT10_STRIP_VLAN, NXAST_POP_QUEUE, NXAST_EXIT,
 189  * OFPAT11_POP_VLAN, OFPIT11_CLEAR_ACTIONS.
 190  *
 191  * Action structure for actions that do not have any extra data beyond the
 192  * action type. */
 193 struct ofpact_null {
 194     struct ofpact ofpact;
 195 };
 196
 197 /* OFPACT_OUTPUT.
 198  *
 199  * Used for OFPAT10_OUTPUT. */
 200 struct ofpact_output {
 201     struct ofpact ofpact;
 202     ofp_port_t port;            /* Output port. */
 203     uint16_t max_len;           /* Max send len, for port OFPP_CONTROLLER. */
 204 };
 205
 206 /* OFPACT_CONTROLLER.
 207  *
 208  * Used for NXAST_CONTROLLER. */
 209 struct ofpact_controller {
 210     struct ofpact ofpact;
 211     uint16_t max_len;           /* Maximum length to send to controller. */
 212     uint16_t controller_id;     /* Controller ID to send packet-in. */
 213     enum ofp_packet_in_reason reason; /* Reason to put in packet-in. */
 214 };
 215
 216 /* OFPACT_ENQUEUE.
 217  *
 218  * Used for OFPAT10_ENQUEUE. */
 219 struct ofpact_enqueue {
 220     struct ofpact ofpact;
 221     ofp_port_t port;
 222     uint32_t queue;
 223 };
 224
 225 /* OFPACT_OUTPUT_REG.
 226  *
 227  * Used for NXAST_OUTPUT_REG. */
 228 struct ofpact_output_reg {
 229     struct ofpact ofpact;
 230     struct mf_subfield src;
 231     uint16_t max_len;
 232 };
 233
 234 /* OFPACT_BUNDLE.
 235  *
 236  * Used for NXAST_BUNDLE. */
 237 struct ofpact_bundle {
 238     struct ofpact ofpact;
 239
 240     /* Slave choice algorithm to apply to hash value. */
 241     enum nx_bd_algorithm algorithm;
 242
 243     /* What fields to hash and how. */
 244     enum nx_hash_fields fields;
 245     uint16_t basis;             /* Universal hash parameter. */
 246
 247     struct mf_subfield dst;
 248
 249     /* Slaves for output. */
 250     unsigned int n_slaves;
 251     ofp_port_t slaves[];
 252 };
 253
 254 /* OFPACT_SET_VLAN_VID.
 255  *
 256  * Used for OFPAT10_SET_VLAN_VID. */
 257 struct ofpact_vlan_vid {
 258     struct ofpact ofpact;
 259     uint16_t vlan_vid;          /* VLAN VID in low 12 bits, 0 in other bits. */
 260 };
 261
 262 /* OFPACT_SET_VLAN_PCP.
 263  *
 264  * Used for OFPAT10_SET_VLAN_PCP. */
 265 struct ofpact_vlan_pcp {
 266     struct ofpact ofpact;
 267     uint8_t vlan_pcp;           /* VLAN PCP in low 3 bits, 0 in other bits. */
 268 };
 269
 270 /* OFPACT_SET_ETH_SRC, OFPACT_SET_ETH_DST.
 271  *
 272  * Used for OFPAT10_SET_DL_SRC, OFPAT10_SET_DL_DST. */
 273 struct ofpact_mac {
 274     struct ofpact ofpact;
 275     uint8_t mac[ETH_ADDR_LEN];
 276 };
 277
 278 /* OFPACT_SET_IPV4_SRC, OFPACT_SET_IPV4_DST.
 279  *
 280  * Used for OFPAT10_SET_NW_SRC, OFPAT10_SET_NW_DST. */
 281 struct ofpact_ipv4 {
 282     struct ofpact ofpact;
 283     ovs_be32 ipv4;
 284 };
 285
 286 /* OFPACT_SET_IPV4_DSCP.
 287  *
 288  * Used for OFPAT10_SET_NW_TOS. */
 289 struct ofpact_dscp {
 290     struct ofpact ofpact;
 291     uint8_t dscp;               /* DSCP in high 6 bits, rest ignored. */
 292 };
 293
 294 /* OFPACT_SET_L4_SRC_PORT, OFPACT_SET_L4_DST_PORT.
 295  *
 296  * Used for OFPAT10_SET_TP_SRC, OFPAT10_SET_TP_DST. */
 297 struct ofpact_l4_port {
 298     struct ofpact ofpact;
 299     uint16_t port;              /* TCP or UDP port number. */
 300 };
 301
 302 /* OFPACT_REG_MOVE.
 303  *
 304  * Used for NXAST_REG_MOVE. */
 305 struct ofpact_reg_move {
 306     struct ofpact ofpact;
 307     struct mf_subfield src;
 308     struct mf_subfield dst;
 309 };
 310
 311 /* OFPACT_STACK_PUSH.
 312  *
 313  * Used for NXAST_STACK_PUSH and NXAST_STACK_POP. */
 314 struct ofpact_stack {
 315     struct ofpact ofpact;
 316     struct mf_subfield subfield;
 317 };
 318
 319 /* OFPACT_REG_LOAD.
 320  *
 321  * Used for NXAST_REG_LOAD, OFPAT12_SET_FIELD. */
 322 struct ofpact_reg_load {
 323     struct ofpact ofpact;
 324     struct mf_subfield dst;
 325     union mf_subvalue subvalue; /* Least-significant bits are used. */
 326 };
 327
 328 /* OFPACT_PUSH_VLAN/MPLS/PBB
 329  *
 330  * Used for NXAST_PUSH_MPLS, OFPAT11_PUSH_MPLS. */
 331 struct ofpact_push_mpls {
 332     struct ofpact ofpact;
 333     ovs_be16 ethertype;
 334 };
 335
 336 /* OFPACT_POP_MPLS
 337  *
 338  * Used for NXAST_POP_MPLS, OFPAT11_POP_MPLS.. */
 339 struct ofpact_pop_mpls {
 340     struct ofpact ofpact;
 341     ovs_be16 ethertype;
 342 };
 343
 344 /* OFPACT_SET_TUNNEL.
 345  *
 346  * Used for NXAST_SET_TUNNEL, NXAST_SET_TUNNEL64. */
 347 struct ofpact_tunnel {
 348     struct ofpact ofpact;
 349     uint64_t tun_id;
 350 };
 351
 352 /* OFPACT_SET_QUEUE.
 353  *
 354  * Used for NXAST_SET_QUEUE. */
 355 struct ofpact_queue {
 356     struct ofpact ofpact;
 357     uint32_t queue_id;
 358 };
 359
 360 /* OFPACT_FIN_TIMEOUT.
 361  *
 362  * Used for NXAST_FIN_TIMEOUT. */
 363 struct ofpact_fin_timeout {
 364     struct ofpact ofpact;
 365     uint16_t fin_idle_timeout;
 366     uint16_t fin_hard_timeout;
 367 };
 368
 369 /* OFPACT_WRITE_METADATA.
 370  *
 371  * Used for NXAST_WRITE_METADATA. */
 372 struct ofpact_metadata {
 373     struct ofpact ofpact;
 374     ovs_be64 metadata;
 375     ovs_be64 mask;
 376 };
 377
 378 /* OFPACT_METER.
 379  *
 380  * Used for OFPIT13_METER. */
 381 struct ofpact_meter {
 382     struct ofpact ofpact;
 383     uint32_t meter_id;
 384 };
 385
 386 /* OFPACT_RESUBMIT.
 387  *
 388  * Used for NXAST_RESUBMIT, NXAST_RESUBMIT_TABLE. */
 389 struct ofpact_resubmit {
 390     struct ofpact ofpact;
 391     ofp_port_t in_port;
 392     uint8_t table_id;
 393 };
 394
 395 /* Part of struct ofpact_learn, below. */
 396 struct ofpact_learn_spec {
 397     int n_bits;                 /* Number of bits in source and dest. */
 398
 399     int src_type;               /* One of NX_LEARN_SRC_*. */
 400     struct mf_subfield src;     /* NX_LEARN_SRC_FIELD only. */
 401     union mf_subvalue src_imm;  /* NX_LEARN_SRC_IMMEDIATE only. */
 402
 403     int dst_type;             /* One of NX_LEARN_DST_*. */
 404     struct mf_subfield dst;   /* NX_LEARN_DST_MATCH, NX_LEARN_DST_LOAD only. */
 405 };
 406
 407 /* OFPACT_LEARN.
 408  *
 409  * Used for NXAST_LEARN. */
 410 struct ofpact_learn {
 411     struct ofpact ofpact;
 412
 413     uint16_t idle_timeout;      /* Idle time before discarding (seconds). */
 414     uint16_t hard_timeout;      /* Max time before discarding (seconds). */
 415     uint16_t priority;          /* Priority level of flow entry. */
 416     uint64_t cookie;            /* Cookie for new flow. */
 417     uint16_t flags;             /* Either 0 or OFPFF_SEND_FLOW_REM. */
 418     uint8_t table_id;           /* Table to insert flow entry. */
 419     uint16_t fin_idle_timeout;  /* Idle timeout after FIN, if nonzero. */
 420     uint16_t fin_hard_timeout;  /* Hard timeout after FIN, if nonzero. */
 421
 422     unsigned int n_specs;
 423     struct ofpact_learn_spec specs[];
 424 };
 425
 426 /* OFPACT_MULTIPATH.
 427  *
 428  * Used for NXAST_MULTIPATH. */
 429 struct ofpact_multipath {
 430     struct ofpact ofpact;
 431
 432     /* What fields to hash and how. */
 433     enum nx_hash_fields fields;
 434     uint16_t basis;             /* Universal hash parameter. */
 435
 436     /* Multipath link choice algorithm to apply to hash value. */
 437     enum nx_mp_algorithm algorithm;
 438     uint16_t max_link;          /* Number of output links, minus 1. */
 439     uint32_t arg;               /* Algorithm-specific argument. */
 440
 441     /* Where to store the result. */
 442     struct mf_subfield dst;
 443 };
 444
 445 /* OFPACT_NOTE.
 446  *
 447  * Used for NXAST_NOTE. */
 448 struct ofpact_note {
 449     struct ofpact ofpact;
 450     size_t length;
 451     uint8_t data[];
 452 };
 453
 454 /* OFPACT_SAMPLE.
 455  *
 456  * Used for NXAST_SAMPLE. */
 457 struct ofpact_sample {
 458     struct ofpact ofpact;
 459     uint16_t probability;  // Always >0.
 460     uint32_t collector_set_id;
 461     uint32_t obs_domain_id;
 462     uint32_t obs_point_id;
 463 };
 464
 465 /* OFPACT_DEC_TTL.
 466  *
 467  * Used for OFPAT11_DEC_NW_TTL, NXAST_DEC_TTL and NXAST_DEC_TTL_CNT_IDS. */
 468 struct ofpact_cnt_ids {
 469     struct ofpact ofpact;
 470
 471     /* Controller ids. */
 472     unsigned int n_controllers;
 473     uint16_t cnt_ids[];
 474 };
 475
 476 /* OFPACT_SET_MPLS_TTL.
 477  *
 478  * Used for NXAST_SET_MPLS_TTL */
 479 struct ofpact_mpls_ttl {
 480     struct ofpact ofpact;
 481
 482     uint8_t ttl;
 483 };
 484
 485 /* OFPACT_GOTO_TABLE
 486  *
 487  * Used for OFPIT11_GOTO_TABLE */
 488 struct ofpact_goto_table {
 489     struct ofpact ofpact;
 490     uint8_t table_id;
 491 };
 492
 493 /* Converting OpenFlow to ofpacts. */
 494 enum ofperr ofpacts_pull_openflow10(struct ofpbuf *openflow,
 495                                     unsigned int actions_len,
 496                                     struct ofpbuf *ofpacts);
 497 enum ofperr ofpacts_pull_openflow11_actions(struct ofpbuf *openflow,
 498                                             unsigned int actions_len,
 499                                             struct ofpbuf *ofpacts);
 500 enum ofperr ofpacts_pull_openflow11_instructions(struct ofpbuf *openflow,
 501                                                  unsigned int instructions_len,
 502                                                  uint8_t table_id,
 503                                                  struct ofpbuf *ofpacts);
 504 enum ofperr ofpacts_check(const struct ofpact[], size_t ofpacts_len,
 505                           struct flow *, ofp_port_t max_ports);
 506 enum ofperr ofpacts_verify(const struct ofpact ofpacts[], size_t ofpacts_len);
 507
 508 /* Converting ofpacts to OpenFlow. */
 509 void ofpacts_put_openflow10(const struct ofpact[], size_t ofpacts_len,
 510                             struct ofpbuf *openflow);
 511 size_t ofpacts_put_openflow11_actions(const struct ofpact[], size_t ofpacts_len,
 512                                       struct ofpbuf *openflow);
 513 void ofpacts_put_openflow11_instructions(const struct ofpact[],
 514                                          size_t ofpacts_len,
 515                                          struct ofpbuf *openflow);
 516
 517 /* Working with ofpacts. */
 518 bool ofpacts_output_to_port(const struct ofpact[], size_t ofpacts_len,
 519                             ofp_port_t port);
 520 bool ofpacts_equal(const struct ofpact a[], size_t a_len,
 521                    const struct ofpact b[], size_t b_len);
 522
 523 /* Formatting ofpacts.
 524  *
 525  * (For parsing ofpacts, see ofp-parse.h.) */
 526 void ofpacts_format(const struct ofpact[], size_t ofpacts_len, struct ds *);
 527
 528 /* Internal use by the helpers below. */
 529 void ofpact_init(struct ofpact *, enum ofpact_type, size_t len);
 530 void *ofpact_put(struct ofpbuf *, enum ofpact_type, size_t len);
 531
 532 /* For each OFPACT_<ENUM> with a corresponding struct <STRUCT>, this defines
 533  * the following commonly useful functions:
 534  *
 535  *   struct <STRUCT> *ofpact_put_<ENUM>(struct ofpbuf *ofpacts);
 536  *
 537  *     Appends a new 'ofpact', of length OFPACT_<ENUM>_RAW_SIZE, to 'ofpacts',
 538  *     initializes it with ofpact_init_<ENUM>(), and returns it.  Also sets
 539  *     'ofpacts->l2' to the returned action.
 540  *
 541  *     After using this function to add a variable-length action, add the
 542  *     elements of the flexible array (e.g. with ofpbuf_put()), then use
 543  *     ofpact_update_len() to update the length embedded into the action.
 544  *     (Keep in mind the need to refresh the structure from 'ofpacts->l2' after
 545  *     adding data to 'ofpacts'.)
 546  *
 547  *   struct <STRUCT> *ofpact_get_<ENUM>(const struct ofpact *ofpact);
 548  *
 549  *     Returns 'ofpact' cast to "struct <STRUCT> *".  'ofpact->type' must be
 550  *     OFPACT_<ENUM>.
 551  *
 552  * as well as the following more rarely useful definitions:
 553  *
 554  *   void ofpact_init_<ENUM>(struct <STRUCT> *ofpact);
 555  *
 556  *     Initializes the parts of 'ofpact' that identify it as having type
 557  *     OFPACT_<ENUM> and length OFPACT_<ENUM>_RAW_SIZE and zeros the rest.
 558  *
 559  *   <ENUM>_RAW_SIZE
 560  *
 561  *     The size of the action structure.  For a fixed-length action, this is
 562  *     sizeof(struct <STRUCT>).  For a variable-length action, this is the
 563  *     offset to the variable-length part.
 564  *
 565  *   <ENUM>_SIZE
 566  *
 567  *     An integer constant, the value of OFPACT_<ENUM>_RAW_SIZE rounded up to a
 568  *     multiple of OFPACT_ALIGNTO.
 569  */
 570 #define DEFINE_OFPACT(ENUM, STRUCT, MEMBER)                             \
 571     BUILD_ASSERT_DECL(offsetof(struct STRUCT, ofpact) == 0);            \
 572                                                                         \
 573     enum { OFPACT_##ENUM##_RAW_SIZE                                     \
 574            = (offsetof(struct STRUCT, MEMBER)                           \
 575               ? offsetof(struct STRUCT, MEMBER)                         \
 576               : sizeof(struct STRUCT)) };                               \
 577                                                                         \
 578     enum { OFPACT_##ENUM##_SIZE                                         \
 579            = ROUND_UP(OFPACT_##ENUM##_RAW_SIZE, OFPACT_ALIGNTO) };      \
 580                                                                         \
 581     static inline struct STRUCT *                                       \
 582     ofpact_get_##ENUM(const struct ofpact *ofpact)                      \
 583     {                                                                   \
 584         ovs_assert(ofpact->type == OFPACT_##ENUM);                      \
 585         return (struct STRUCT *) ofpact;                                \
 586     }                                                                   \
 587                                                                         \
 588     static inline struct STRUCT *                                       \
 589     ofpact_put_##ENUM(struct ofpbuf *ofpacts)                           \
 590     {                                                                   \
 591         return ofpact_put(ofpacts, OFPACT_##ENUM,                       \
 592                           OFPACT_##ENUM##_RAW_SIZE);                    \
 593     }                                                                   \
 594                                                                         \
 595     static inline void                                                  \
 596     ofpact_init_##ENUM(struct STRUCT *ofpact)                           \
 597     {                                                                   \
 598         ofpact_init(&ofpact->ofpact, OFPACT_##ENUM,                     \
 599                     OFPACT_##ENUM##_RAW_SIZE);                          \
 600     }
 601 OFPACTS
 602 #undef DEFINE_OFPACT
 603
 604 /* Functions to use after adding ofpacts to a buffer. */
 605 void ofpact_update_len(struct ofpbuf *, struct ofpact *);
 606 void ofpact_pad(struct ofpbuf *);
 607
 608 /* OpenFlow 1.1 instructions.
 609  * The order is sorted in execution order. Not in the value of OFPIT11_xxx.
 610  * It is enforced on parser from text string.
 611  */
 612 #define OVS_INSTRUCTIONS                                    \
 613     DEFINE_INST(OFPIT13_METER,                              \
 614                 ofp13_instruction_meter,          false,    \
 615                 "meter")                                    \
 616                                                             \
 617     DEFINE_INST(OFPIT11_APPLY_ACTIONS,                      \
 618                 ofp11_instruction_actions,        true,     \
 619                 "apply_actions")                            \
 620                                                             \
 621     DEFINE_INST(OFPIT11_CLEAR_ACTIONS,                      \
 622                 ofp11_instruction,                false,    \
 623                 "clear_actions")                            \
 624                                                             \
 625     DEFINE_INST(OFPIT11_WRITE_ACTIONS,                      \
 626                 ofp11_instruction_actions,        true,     \
 627                 "write_actions")                            \
 628                                                             \
 629     DEFINE_INST(OFPIT11_WRITE_METADATA,                     \
 630                 ofp11_instruction_write_metadata, false,    \
 631                 "write_metadata")                           \
 632                                                             \
 633     DEFINE_INST(OFPIT11_GOTO_TABLE,                         \
 634                 ofp11_instruction_goto_table,     false,    \
 635                 "goto_table")
 636
 637 enum ovs_instruction_type {
 638 #define DEFINE_INST(ENUM, STRUCT, EXTENSIBLE, NAME) OVSINST_##ENUM,
 639     OVS_INSTRUCTIONS
 640 #undef DEFINE_INST
 641 };
 642
 643 enum {
 644 #define DEFINE_INST(ENUM, STRUCT, EXTENSIBLE, NAME) + 1
 645     N_OVS_INSTRUCTIONS = OVS_INSTRUCTIONS
 646 #undef DEFINE_INST
 647 };
 648
 649
 650 static inline bool
 651 ofpact_is_instruction(const struct ofpact *a)
 652 {
 653     /* XXX Write-Actions */
 654     return a->type == OFPACT_CLEAR_ACTIONS
 655         || a->type == OFPACT_METER
 656         || a->type == OFPACT_WRITE_METADATA
 657         || a->type == OFPACT_GOTO_TABLE;
 658 }
 659
 660 const char *ofpact_instruction_name_from_type(enum ovs_instruction_type type);
 661 int ofpact_instruction_type_from_name(const char *name);
 662
 663 void ofpact_set_field_init(struct ofpact_reg_load *load,
 664                            const struct mf_field *mf, const void *src);
 665
 666 #endif /* ofp-actions.h */