lib/ofp-util.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
  17 #ifndef OFP_UTIL_H
  18 #define OFP_UTIL_H 1
  19
  20 #include <assert.h>
  21 #include <stdbool.h>
  22 #include <stddef.h>
  23 #include <stdint.h>
  24 #include "classifier.h"
  25 #include "flow.h"
  26 #include "openflow/nicira-ext.h"
  27 #include "openvswitch/types.h"
  28
  29 struct cls_rule;
  30 struct ofpbuf;
  31
  32 /* Basic decoding and length validation of OpenFlow messages. */
  33 enum ofputil_msg_code {
  34     OFPUTIL_MSG_INVALID,
  35
  36     /* OFPT_* messages. */
  37     OFPUTIL_OFPT_HELLO,
  38     OFPUTIL_OFPT_ERROR,
  39     OFPUTIL_OFPT_ECHO_REQUEST,
  40     OFPUTIL_OFPT_ECHO_REPLY,
  41     OFPUTIL_OFPT_FEATURES_REQUEST,
  42     OFPUTIL_OFPT_FEATURES_REPLY,
  43     OFPUTIL_OFPT_GET_CONFIG_REQUEST,
  44     OFPUTIL_OFPT_GET_CONFIG_REPLY,
  45     OFPUTIL_OFPT_SET_CONFIG,
  46     OFPUTIL_OFPT_PACKET_IN,
  47     OFPUTIL_OFPT_FLOW_REMOVED,
  48     OFPUTIL_OFPT_PORT_STATUS,
  49     OFPUTIL_OFPT_PACKET_OUT,
  50     OFPUTIL_OFPT_FLOW_MOD,
  51     OFPUTIL_OFPT_PORT_MOD,
  52     OFPUTIL_OFPT_BARRIER_REQUEST,
  53     OFPUTIL_OFPT_BARRIER_REPLY,
  54     OFPUTIL_OFPT_QUEUE_GET_CONFIG_REQUEST,
  55     OFPUTIL_OFPT_QUEUE_GET_CONFIG_REPLY,
  56
  57     /* OFPST_* stat requests. */
  58     OFPUTIL_OFPST_DESC_REQUEST,
  59     OFPUTIL_OFPST_FLOW_REQUEST,
  60     OFPUTIL_OFPST_AGGREGATE_REQUEST,
  61     OFPUTIL_OFPST_TABLE_REQUEST,
  62     OFPUTIL_OFPST_PORT_REQUEST,
  63     OFPUTIL_OFPST_QUEUE_REQUEST,
  64
  65     /* OFPST_* stat replies. */
  66     OFPUTIL_OFPST_DESC_REPLY,
  67     OFPUTIL_OFPST_FLOW_REPLY,
  68     OFPUTIL_OFPST_QUEUE_REPLY,
  69     OFPUTIL_OFPST_PORT_REPLY,
  70     OFPUTIL_OFPST_TABLE_REPLY,
  71     OFPUTIL_OFPST_AGGREGATE_REPLY,
  72
  73     /* NXT_* messages. */
  74     OFPUTIL_NXT_ROLE_REQUEST,
  75     OFPUTIL_NXT_ROLE_REPLY,
  76     OFPUTIL_NXT_SET_FLOW_FORMAT,
  77     OFPUTIL_NXT_FLOW_MOD_TABLE_ID,
  78     OFPUTIL_NXT_FLOW_MOD,
  79     OFPUTIL_NXT_FLOW_REMOVED,
  80
  81     /* NXST_* stat requests. */
  82     OFPUTIL_NXST_FLOW_REQUEST,
  83     OFPUTIL_NXST_AGGREGATE_REQUEST,
  84
  85     /* NXST_* stat replies. */
  86     OFPUTIL_NXST_FLOW_REPLY,
  87     OFPUTIL_NXST_AGGREGATE_REPLY
  88 };
  89
  90 struct ofputil_msg_type;
  91 int ofputil_decode_msg_type(const struct ofp_header *,
  92                             const struct ofputil_msg_type **);
  93 enum ofputil_msg_code ofputil_msg_type_code(const struct ofputil_msg_type *);
  94 const char *ofputil_msg_type_name(const struct ofputil_msg_type *);
  95 int ofputil_check_output_port(uint16_t ofp_port, int max_ports);
  96
  97 /* Converting OFPFW_NW_SRC_MASK and OFPFW_NW_DST_MASK wildcard bit counts to
  98  * and from IP bitmasks. */
  99 ovs_be32 ofputil_wcbits_to_netmask(int wcbits);
 100 int ofputil_netmask_to_wcbits(ovs_be32 netmask);
 101
 102 /* Work with OpenFlow 1.0 ofp_match. */
 103 void ofputil_wildcard_from_openflow(uint32_t ofpfw, struct flow_wildcards *);
 104 void ofputil_cls_rule_from_match(const struct ofp_match *,
 105                                  unsigned int priority, struct cls_rule *);
 106 void ofputil_normalize_rule(struct cls_rule *, enum nx_flow_format);
 107 void ofputil_cls_rule_to_match(const struct cls_rule *, struct ofp_match *);
 108
 109 /* dl_type translation between OpenFlow and 'struct flow' format. */
 110 ovs_be16 ofputil_dl_type_to_openflow(ovs_be16 flow_dl_type);
 111 ovs_be16 ofputil_dl_type_from_openflow(ovs_be16 ofp_dl_type);
 112
 113 /* Flow formats. */
 114 bool ofputil_flow_format_is_valid(enum nx_flow_format);
 115 const char *ofputil_flow_format_to_string(enum nx_flow_format);
 116 int ofputil_flow_format_from_string(const char *);
 117 enum nx_flow_format ofputil_min_flow_format(const struct cls_rule *);
 118
 119 struct ofpbuf *ofputil_make_set_flow_format(enum nx_flow_format);
 120
 121 /* NXT_FLOW_MOD_TABLE_ID extension. */
 122 struct ofpbuf *ofputil_make_flow_mod_table_id(bool flow_mod_table_id);
 123
 124 /* Flow format independent flow_mod. */
 125 struct flow_mod {
 126     struct cls_rule cr;
 127     ovs_be64 cookie;
 128     uint8_t table_id;
 129     uint16_t command;
 130     uint16_t idle_timeout;
 131     uint16_t hard_timeout;
 132     uint32_t buffer_id;
 133     uint16_t out_port;
 134     uint16_t flags;
 135     union ofp_action *actions;
 136     size_t n_actions;
 137 };
 138
 139 int ofputil_decode_flow_mod(struct flow_mod *, const struct ofp_header *,
 140                             bool flow_mod_table_id);
 141 struct ofpbuf *ofputil_encode_flow_mod(const struct flow_mod *,
 142                                        enum nx_flow_format,
 143                                        bool flow_mod_table_id);
 144
 145 /* Flow stats or aggregate stats request, independent of flow format. */
 146 struct flow_stats_request {
 147     bool aggregate;             /* Aggregate results? */
 148     struct cls_rule match;
 149     uint16_t out_port;
 150     uint8_t table_id;
 151 };
 152
 153 int ofputil_decode_flow_stats_request(struct flow_stats_request *,
 154                                       const struct ofp_header *);
 155 struct ofpbuf *ofputil_encode_flow_stats_request(
 156     const struct flow_stats_request *, enum nx_flow_format);
 157
 158 /* Flow stats reply, independent of flow format. */
 159 struct ofputil_flow_stats {
 160     struct cls_rule rule;
 161     ovs_be64 cookie;
 162     uint8_t table_id;
 163     uint32_t duration_sec;
 164     uint32_t duration_nsec;
 165     uint16_t idle_timeout;
 166     uint16_t hard_timeout;
 167     uint64_t packet_count;      /* Packet count, UINT64_MAX if unknown. */
 168     uint64_t byte_count;        /* Byte count, UINT64_MAX if unknown. */
 169     union ofp_action *actions;
 170     size_t n_actions;
 171 };
 172
 173 int ofputil_decode_flow_stats_reply(struct ofputil_flow_stats *,
 174                                     struct ofpbuf *msg);
 175 void ofputil_append_flow_stats_reply(const struct ofputil_flow_stats *,
 176                                      struct list *replies);
 177
 178 /* Aggregate stats reply, independent of flow format. */
 179 struct ofputil_aggregate_stats {
 180     uint64_t packet_count;      /* Packet count, UINT64_MAX if unknown. */
 181     uint64_t byte_count;        /* Byte count, UINT64_MAX if unknown. */
 182     uint32_t flow_count;
 183 };
 184
 185 struct ofpbuf *ofputil_encode_aggregate_stats_reply(
 186     const struct ofputil_aggregate_stats *stats,
 187     const struct ofp_stats_msg *request);
 188
 189 /* Flow removed message, independent of flow format. */
 190 struct ofputil_flow_removed {
 191     struct cls_rule rule;
 192     ovs_be64 cookie;
 193     uint8_t reason;             /* One of OFPRR_*. */
 194     uint32_t duration_sec;
 195     uint32_t duration_nsec;
 196     uint16_t idle_timeout;
 197     uint64_t packet_count;      /* Packet count, UINT64_MAX if unknown. */
 198     uint64_t byte_count;        /* Byte count, UINT64_MAX if unknown. */
 199 };
 200
 201 int ofputil_decode_flow_removed(struct ofputil_flow_removed *,
 202                                 const struct ofp_header *);
 203 struct ofpbuf *ofputil_encode_flow_removed(const struct ofputil_flow_removed *,
 204                                            enum nx_flow_format);
 205
 206 /* Abstract packet-in message. */
 207 struct ofputil_packet_in {
 208     struct ofpbuf *packet;
 209     uint16_t in_port;
 210     uint8_t reason;             /* One of OFPR_*. */
 211
 212     uint32_t buffer_id;
 213     int send_len;
 214 };
 215
 216 struct ofpbuf *ofputil_encode_packet_in(const struct ofputil_packet_in *,
 217                                         struct ofpbuf *rw_packet);
 218
 219 /* OpenFlow protocol utility functions. */
 220 void *make_openflow(size_t openflow_len, uint8_t type, struct ofpbuf **);
 221 void *make_nxmsg(size_t openflow_len, uint32_t subtype, struct ofpbuf **);
 222
 223 void *make_openflow_xid(size_t openflow_len, uint8_t type,
 224                         ovs_be32 xid, struct ofpbuf **);
 225 void *make_nxmsg_xid(size_t openflow_len, uint32_t subtype, ovs_be32 xid,
 226                      struct ofpbuf **);
 227
 228 void *put_openflow(size_t openflow_len, uint8_t type, struct ofpbuf *);
 229 void *put_openflow_xid(size_t openflow_len, uint8_t type, ovs_be32 xid,
 230                        struct ofpbuf *);
 231
 232 void *put_nxmsg(size_t openflow_len, uint32_t subtype, struct ofpbuf *);
 233 void *put_nxmsg_xid(size_t openflow_len, uint32_t subtype, ovs_be32 xid,
 234                     struct ofpbuf *);
 235
 236 void update_openflow_length(struct ofpbuf *);
 237
 238 void *ofputil_make_stats_request(size_t openflow_len, uint16_t type,
 239                                  uint32_t subtype, struct ofpbuf **);
 240 void *ofputil_make_stats_reply(size_t openflow_len,
 241                                const struct ofp_stats_msg *request,
 242                                struct ofpbuf **);
 243
 244 void ofputil_start_stats_reply(const struct ofp_stats_msg *request,
 245                                struct list *);
 246 struct ofpbuf *ofputil_reserve_stats_reply(size_t len, struct list *);
 247 void *ofputil_append_stats_reply(size_t len, struct list *);
 248
 249 const void *ofputil_stats_body(const struct ofp_header *);
 250 size_t ofputil_stats_body_len(const struct ofp_header *);
 251
 252 const void *ofputil_nxstats_body(const struct ofp_header *);
 253 size_t ofputil_nxstats_body_len(const struct ofp_header *);
 254
 255 struct ofpbuf *make_flow_mod(uint16_t command, const struct cls_rule *,
 256                              size_t actions_len);
 257 struct ofpbuf *make_add_flow(const struct cls_rule *, uint32_t buffer_id,
 258                              uint16_t max_idle, size_t actions_len);
 259 struct ofpbuf *make_del_flow(const struct cls_rule *);
 260 struct ofpbuf *make_add_simple_flow(const struct cls_rule *,
 261                                     uint32_t buffer_id, uint16_t out_port,
 262                                     uint16_t max_idle);
 263 struct ofpbuf *make_packet_in(uint32_t buffer_id, uint16_t in_port,
 264                               uint8_t reason,
 265                               const struct ofpbuf *payload, int max_send_len);
 266 struct ofpbuf *make_packet_out(const struct ofpbuf *packet, uint32_t buffer_id,
 267                                uint16_t in_port,
 268                                const struct ofp_action_header *,
 269                                size_t n_actions);
 270 struct ofpbuf *make_buffered_packet_out(uint32_t buffer_id,
 271                                         uint16_t in_port, uint16_t out_port);
 272 struct ofpbuf *make_unbuffered_packet_out(const struct ofpbuf *packet,
 273                                           uint16_t in_port, uint16_t out_port);
 274 struct ofpbuf *make_echo_request(void);
 275 struct ofpbuf *make_echo_reply(const struct ofp_header *rq);
 276 \f
 277 /* Actions. */
 278
 279 enum ofputil_action_code {
 280     /* OFPAT_* actions. */
 281     OFPUTIL_OFPAT_OUTPUT,
 282     OFPUTIL_OFPAT_SET_VLAN_VID,
 283     OFPUTIL_OFPAT_SET_VLAN_PCP,
 284     OFPUTIL_OFPAT_STRIP_VLAN,
 285     OFPUTIL_OFPAT_SET_DL_SRC,
 286     OFPUTIL_OFPAT_SET_DL_DST,
 287     OFPUTIL_OFPAT_SET_NW_SRC,
 288     OFPUTIL_OFPAT_SET_NW_DST,
 289     OFPUTIL_OFPAT_SET_NW_TOS,
 290     OFPUTIL_OFPAT_SET_TP_SRC,
 291     OFPUTIL_OFPAT_SET_TP_DST,
 292     OFPUTIL_OFPAT_ENQUEUE,
 293
 294     /* NXAST_* actions. */
 295     OFPUTIL_NXAST_RESUBMIT,
 296     OFPUTIL_NXAST_SET_TUNNEL,
 297     OFPUTIL_NXAST_SET_QUEUE,
 298     OFPUTIL_NXAST_POP_QUEUE,
 299     OFPUTIL_NXAST_REG_MOVE,
 300     OFPUTIL_NXAST_REG_LOAD,
 301     OFPUTIL_NXAST_NOTE,
 302     OFPUTIL_NXAST_SET_TUNNEL64,
 303     OFPUTIL_NXAST_MULTIPATH,
 304     OFPUTIL_NXAST_AUTOPATH,
 305     OFPUTIL_NXAST_BUNDLE,
 306     OFPUTIL_NXAST_BUNDLE_LOAD,
 307 };
 308
 309 int ofputil_decode_action(const union ofp_action *);
 310 enum ofputil_action_code ofputil_decode_action_unsafe(
 311     const union ofp_action *);
 312
 313 #define OFP_ACTION_ALIGN 8      /* Alignment of ofp_actions. */
 314
 315 static inline union ofp_action *
 316 ofputil_action_next(const union ofp_action *a)
 317 {
 318     return (void *) ((uint8_t *) a + ntohs(a->header.len));
 319 }
 320
 321 static inline bool
 322 ofputil_action_is_valid(const union ofp_action *a, size_t n_actions)
 323 {
 324     uint16_t len = ntohs(a->header.len);
 325     return (!(len % OFP_ACTION_ALIGN)
 326             && len >= sizeof *a
 327             && len / sizeof *a <= n_actions);
 328 }
 329
 330 /* This macro is careful to check for actions with bad lengths. */
 331 #define OFPUTIL_ACTION_FOR_EACH(ITER, LEFT, ACTIONS, N_ACTIONS)         \
 332     for ((ITER) = (ACTIONS), (LEFT) = (N_ACTIONS);                      \
 333          (LEFT) > 0 && ofputil_action_is_valid(ITER, LEFT);             \
 334          ((LEFT) -= ntohs((ITER)->header.len) / sizeof(union ofp_action), \
 335           (ITER) = ofputil_action_next(ITER)))
 336
 337 /* This macro does not check for actions with bad lengths.  It should only be
 338  * used with actions from trusted sources or with actions that have already
 339  * been validated (e.g. with OFPUTIL_ACTION_FOR_EACH).  */
 340 #define OFPUTIL_ACTION_FOR_EACH_UNSAFE(ITER, LEFT, ACTIONS, N_ACTIONS)  \
 341     for ((ITER) = (ACTIONS), (LEFT) = (N_ACTIONS);                      \
 342          (LEFT) > 0;                                                    \
 343          ((LEFT) -= ntohs((ITER)->header.len) / sizeof(union ofp_action), \
 344           (ITER) = ofputil_action_next(ITER)))
 345
 346 int validate_actions(const union ofp_action *, size_t n_actions,
 347                      const struct flow *, int max_ports);
 348 bool action_outputs_to_port(const union ofp_action *, ovs_be16 port);
 349
 350 int ofputil_pull_actions(struct ofpbuf *, unsigned int actions_len,
 351                          union ofp_action **, size_t *);
 352
 353 bool ofputil_actions_equal(const union ofp_action *a, size_t n_a,
 354                            const union ofp_action *b, size_t n_b);
 355 union ofp_action *ofputil_actions_clone(const union ofp_action *, size_t n);
 356 \f
 357 /* OpenFlow vendors.
 358  *
 359  * These functions map OpenFlow 32-bit vendor IDs (as used in struct
 360  * ofp_vendor_header) into 4-bit values to embed in an "int".  The 4-bit values
 361  * are only used internally in Open vSwitch and never appear on the wire, so
 362  * particular codes used are not important.
 363  */
 364
 365 /* Vendor error numbers currently used in Open vSwitch. */
 366 #define OFPUTIL_VENDORS                                     \
 367     /*             vendor name              vendor value */ \
 368     OFPUTIL_VENDOR(OFPUTIL_VENDOR_OPENFLOW, 0x00000000)     \
 369     OFPUTIL_VENDOR(OFPUTIL_VENDOR_NICIRA,   NX_VENDOR_ID)
 370
 371 /* OFPUTIL_VENDOR_* definitions. */
 372 enum ofputil_vendor_codes {
 373 #define OFPUTIL_VENDOR(NAME, VENDOR_ID) NAME,
 374     OFPUTIL_VENDORS
 375     OFPUTIL_N_VENDORS
 376 #undef OFPUTIL_VENDOR
 377 };
 378 \f
 379 /* Error codes.
 380  *
 381  * We embed system errno values and OpenFlow standard and vendor extension
 382  * error codes into a single 31-bit space using the following encoding.
 383  * (Bit 31 is unused and assumed 0 to avoid negative "int" values.)
 384  *
 385  *   30                                                   0
 386  *  +------------------------------------------------------+
 387  *  |                           0                          |  success
 388  *  +------------------------------------------------------+
 389  *
 390  *   30 29                                                0
 391  *  +--+---------------------------------------------------+
 392  *  | 0|                    errno value                    |  errno value
 393  *  +--+---------------------------------------------------+
 394  *
 395  *   30 29   26 25            16 15                       0
 396  *  +--+-------+----------------+--------------------------+
 397  *  | 1|   0   |      type      |           code           |  standard OpenFlow
 398  *  +--+-------+----------------+--------------------------+  error
 399  *
 400  *   30 29   26 25            16 15                       0
 401  *  +--+-------+----------------+--------------------------+  Nicira
 402  *  | 1| vendor|      type      |           code           |  NXET_VENDOR
 403  *  +--+-------+----------------+--------------------------+  error extension
 404  *
 405  * C and POSIX say that errno values are positive.  We assume that they are
 406  * less than 2**29.  They are actually less than 65536 on at least Linux,
 407  * FreeBSD, OpenBSD, and Windows.
 408  *
 409  * The 'vendor' field holds one of the OFPUTIL_VENDOR_* codes defined above.
 410  * It must be nonzero.
 411  *
 412  * Negative values are not defined.
 413  */
 414
 415 /* Currently 4 bits are allocated to the "vendor" field.  Make sure that all
 416  * the vendor codes can fit. */
 417 BUILD_ASSERT_DECL(OFPUTIL_N_VENDORS <= 16);
 418
 419 /* These are macro versions of the functions defined below.  The macro versions
 420  * are intended for use in contexts where function calls are not allowed,
 421  * e.g. static initializers and case labels. */
 422 #define OFP_MKERR(TYPE, CODE) ((1 << 30) | ((TYPE) << 16) | (CODE))
 423 #define OFP_MKERR_VENDOR(VENDOR, TYPE, CODE) \
 424         ((1 << 30) | ((VENDOR) << 26) | ((TYPE) << 16) | (CODE))
 425 #define OFP_MKERR_NICIRA(TYPE, CODE) \
 426         OFP_MKERR_VENDOR(OFPUTIL_VENDOR_NICIRA, TYPE, CODE)
 427
 428 /* Returns the standard OpenFlow error with the specified 'type' and 'code' as
 429  * an integer. */
 430 static inline int
 431 ofp_mkerr(uint16_t type, uint16_t code)
 432 {
 433     return OFP_MKERR(type, code);
 434 }
 435
 436 /* Returns the OpenFlow vendor error with the specified 'vendor', 'type', and
 437  * 'code' as an integer.  'vendor' must be an OFPUTIL_VENDOR_* constant. */
 438 static inline int
 439 ofp_mkerr_vendor(uint8_t vendor, uint16_t type, uint16_t code)
 440 {
 441     assert(vendor < OFPUTIL_N_VENDORS);
 442     return OFP_MKERR_VENDOR(vendor, type, code);
 443 }
 444
 445 /* Returns the OpenFlow vendor error with Nicira as vendor, with the specific
 446  * 'type' and 'code', as an integer. */
 447 static inline int
 448 ofp_mkerr_nicira(uint16_t type, uint16_t code)
 449 {
 450     return OFP_MKERR_NICIRA(type, code);
 451 }
 452
 453 /* Returns true if 'error' encodes an OpenFlow standard or vendor extension
 454  * error codes as documented above. */
 455 static inline bool
 456 is_ofp_error(int error)
 457 {
 458     return (error & (1 << 30)) != 0;
 459 }
 460
 461 /* Returns true if 'error' appears to be a system errno value. */
 462 static inline bool
 463 is_errno(int error)
 464 {
 465     return !is_ofp_error(error);
 466 }
 467
 468 /* Returns the "vendor" part of the OpenFlow error code 'error' (which must be
 469  * in the format explained above).  This is normally one of the
 470  * OFPUTIL_VENDOR_* constants.  Returns OFPUTIL_VENDOR_OPENFLOW (0) for a
 471  * standard OpenFlow error. */
 472 static inline uint8_t
 473 get_ofp_err_vendor(int error)
 474 {
 475     return (error >> 26) & 0xf;
 476 }
 477
 478 /* Returns the "type" part of the OpenFlow error code 'error' (which must be in
 479  * the format explained above). */
 480 static inline uint16_t
 481 get_ofp_err_type(int error)
 482 {
 483     return (error >> 16) & 0x3ff;
 484 }
 485
 486 /* Returns the "code" part of the OpenFlow error code 'error' (which must be in
 487  * the format explained above). */
 488 static inline uint16_t
 489 get_ofp_err_code(int error)
 490 {
 491     return error & 0xffff;
 492 }
 493
 494 struct ofpbuf *ofputil_encode_error_msg(int error, const struct ofp_header *);
 495 int ofputil_decode_error_msg(const struct ofp_header *, size_t *payload_ofs);
 496
 497 /* String versions of errors. */
 498 void ofputil_format_error(struct ds *, int error);
 499 char *ofputil_error_to_string(int error);
 500
 501 #endif /* ofp-util.h */