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_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_TUN_ID_FROM_COOKIE,
  75     OFPUTIL_NXT_ROLE_REQUEST,
  76     OFPUTIL_NXT_ROLE_REPLY,
  77     OFPUTIL_NXT_SET_FLOW_FORMAT,
  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
  96 /* Converting OFPFW_NW_SRC_MASK and OFPFW_NW_DST_MASK wildcard bit counts to
  97  * and from IP bitmasks. */
  98 ovs_be32 ofputil_wcbits_to_netmask(int wcbits);
  99 int ofputil_netmask_to_wcbits(ovs_be32 netmask);
 100
 101 /* Work with OpenFlow 1.0 ofp_match. */
 102 void ofputil_cls_rule_from_match(const struct ofp_match *,
 103                                  unsigned int priority, enum nx_flow_format,
 104                                  ovs_be64 cookie, struct cls_rule *);
 105 void ofputil_cls_rule_to_match(const struct cls_rule *, enum nx_flow_format,
 106                                struct ofp_match *,
 107                                ovs_be64 cookie_in, ovs_be64 *cookie_out);
 108 void normalize_match(struct ofp_match *);
 109 char *ofp_match_to_literal_string(const struct ofp_match *match);
 110
 111 /* dl_type translation between OpenFlow and 'struct flow' format. */
 112 ovs_be16 ofputil_dl_type_to_openflow(ovs_be16 flow_dl_type);
 113 ovs_be16 ofputil_dl_type_from_openflow(ovs_be16 ofp_dl_type);
 114
 115 /* Flow formats. */
 116 bool ofputil_flow_format_is_valid(enum nx_flow_format);
 117 const char *ofputil_flow_format_to_string(enum nx_flow_format);
 118 int ofputil_flow_format_from_string(const char *);
 119 enum nx_flow_format ofputil_min_flow_format(const struct cls_rule *,
 120                                             bool cookie_support,
 121                                             ovs_be64 cookie);
 122
 123 struct ofpbuf *ofputil_make_set_flow_format(enum nx_flow_format);
 124
 125 /* Flow format independent flow_mod. */
 126 struct flow_mod {
 127     struct cls_rule cr;
 128     ovs_be64 cookie;
 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                             enum nx_flow_format);
 141 struct ofpbuf *ofputil_encode_flow_mod(const struct flow_mod *,
 142                                        enum nx_flow_format);
 143
 144 /* Flow stats or aggregate stats request, independent of flow format. */
 145 struct flow_stats_request {
 146     bool aggregate;             /* Aggregate results? */
 147     struct cls_rule match;
 148     uint16_t out_port;
 149     uint8_t table_id;
 150 };
 151
 152 int ofputil_decode_flow_stats_request(struct flow_stats_request *,
 153                                       const struct ofp_header *,
 154                                       enum nx_flow_format);
 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;
 168     uint64_t byte_count;
 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                                     enum nx_flow_format);
 176
 177 /* Flow removed message, independent of flow format. */
 178 struct ofputil_flow_removed {
 179     struct cls_rule rule;
 180     ovs_be64 cookie;
 181     uint8_t reason;             /* One of OFPRR_*. */
 182     uint32_t duration_sec;
 183     uint32_t duration_nsec;
 184     uint16_t idle_timeout;
 185     uint64_t packet_count;
 186     uint64_t byte_count;
 187 };
 188
 189 int ofputil_decode_flow_removed(struct ofputil_flow_removed *,
 190                                 const struct ofp_header *,
 191                                 enum nx_flow_format);
 192 struct ofpbuf *ofputil_encode_flow_removed(const struct ofputil_flow_removed *,
 193                                            enum nx_flow_format);
 194
 195 /* Abstract packet-in message. */
 196 struct ofputil_packet_in {
 197     struct ofpbuf *packet;
 198     uint16_t in_port;
 199     uint8_t reason;             /* One of OFPR_*. */
 200
 201     uint32_t buffer_id;
 202     int send_len;
 203 };
 204
 205 struct ofpbuf *ofputil_encode_packet_in(const struct ofputil_packet_in *,
 206                                         struct ofpbuf *rw_packet);
 207
 208 /* OpenFlow protocol utility functions. */
 209 void *make_openflow(size_t openflow_len, uint8_t type, struct ofpbuf **);
 210 void *make_nxmsg(size_t openflow_len, uint32_t subtype, struct ofpbuf **);
 211
 212 void *make_openflow_xid(size_t openflow_len, uint8_t type,
 213                         ovs_be32 xid, struct ofpbuf **);
 214 void *make_nxmsg_xid(size_t openflow_len, uint32_t subtype, ovs_be32 xid,
 215                      struct ofpbuf **);
 216
 217 void *put_openflow(size_t openflow_len, uint8_t type, struct ofpbuf *);
 218 void *put_openflow_xid(size_t openflow_len, uint8_t type, ovs_be32 xid,
 219                        struct ofpbuf *);
 220
 221 void *put_nxmsg(size_t openflow_len, uint32_t subtype, struct ofpbuf *);
 222 void *put_nxmsg_xid(size_t openflow_len, uint32_t subtype, ovs_be32 xid,
 223                     struct ofpbuf *);
 224
 225 void update_openflow_length(struct ofpbuf *);
 226
 227 void *ofputil_make_stats_request(size_t body_len, uint16_t type,
 228                                  struct ofpbuf **);
 229 void *ofputil_make_nxstats_request(size_t openflow_len, uint32_t subtype,
 230                                    struct ofpbuf **);
 231
 232 const void *ofputil_stats_body(const struct ofp_header *);
 233 size_t ofputil_stats_body_len(const struct ofp_header *);
 234
 235 const void *ofputil_nxstats_body(const struct ofp_header *);
 236 size_t ofputil_nxstats_body_len(const struct ofp_header *);
 237
 238 struct ofpbuf *make_flow_mod(uint16_t command, const struct cls_rule *,
 239                              size_t actions_len);
 240 struct ofpbuf *make_add_flow(const struct cls_rule *, uint32_t buffer_id,
 241                              uint16_t max_idle, size_t actions_len);
 242 struct ofpbuf *make_del_flow(const struct cls_rule *);
 243 struct ofpbuf *make_add_simple_flow(const struct cls_rule *,
 244                                     uint32_t buffer_id, uint16_t out_port,
 245                                     uint16_t max_idle);
 246 struct ofpbuf *make_packet_in(uint32_t buffer_id, uint16_t in_port,
 247                               uint8_t reason,
 248                               const struct ofpbuf *payload, int max_send_len);
 249 struct ofpbuf *make_packet_out(const struct ofpbuf *packet, uint32_t buffer_id,
 250                                uint16_t in_port,
 251                                const struct ofp_action_header *,
 252                                size_t n_actions);
 253 struct ofpbuf *make_buffered_packet_out(uint32_t buffer_id,
 254                                         uint16_t in_port, uint16_t out_port);
 255 struct ofpbuf *make_unbuffered_packet_out(const struct ofpbuf *packet,
 256                                           uint16_t in_port, uint16_t out_port);
 257 struct ofpbuf *make_echo_request(void);
 258 struct ofpbuf *make_echo_reply(const struct ofp_header *rq);
 259
 260 struct flow_stats_iterator {
 261     const uint8_t *pos, *end;
 262 };
 263 const struct ofp_flow_stats *flow_stats_first(struct flow_stats_iterator *,
 264                                               const struct ofp_stats_reply *);
 265 const struct ofp_flow_stats *flow_stats_next(struct flow_stats_iterator *);
 266 \f
 267 /* Actions. */
 268
 269 #define OFP_ACTION_ALIGN 8      /* Alignment of ofp_actions. */
 270
 271 struct actions_iterator {
 272     const union ofp_action *pos, *end;
 273 };
 274 const union ofp_action *actions_first(struct actions_iterator *,
 275                                       const union ofp_action *,
 276                                       size_t n_actions);
 277 const union ofp_action *actions_next(struct actions_iterator *);
 278
 279 int validate_actions(const union ofp_action *, size_t n_actions,
 280                      const struct flow *, int max_ports);
 281 bool action_outputs_to_port(const union ofp_action *, uint16_t port);
 282
 283 int ofputil_pull_actions(struct ofpbuf *, unsigned int actions_len,
 284                          union ofp_action **, size_t *);
 285 \f
 286 /* OpenFlow vendors.
 287  *
 288  * These functions map OpenFlow 32-bit vendor IDs (as used in struct
 289  * ofp_vendor_header) into 4-bit values to embed in an "int".  The 4-bit values
 290  * are only used internally in Open vSwitch and never appear on the wire, so
 291  * particular codes used are not important.
 292  */
 293
 294 /* Vendor error numbers currently used in Open vSwitch. */
 295 #define OFPUTIL_VENDORS                                     \
 296     /*             vendor name              vendor value */ \
 297     OFPUTIL_VENDOR(OFPUTIL_VENDOR_OPENFLOW, 0x00000000)     \
 298     OFPUTIL_VENDOR(OFPUTIL_VENDOR_NICIRA,   NX_VENDOR_ID)
 299
 300 /* OFPUTIL_VENDOR_* definitions. */
 301 enum ofputil_vendor_codes {
 302 #define OFPUTIL_VENDOR(NAME, VENDOR_ID) NAME,
 303     OFPUTIL_VENDORS
 304     OFPUTIL_N_VENDORS
 305 #undef OFPUTIL_VENDOR
 306 };
 307 \f
 308 /* Error codes.
 309  *
 310  * We embed system errno values and OpenFlow standard and vendor extension
 311  * error codes into a single 31-bit space using the following encoding.
 312  * (Bit 31 is unused and assumed 0 to avoid negative "int" values.)
 313  *
 314  *   30                                                   0
 315  *  +------------------------------------------------------+
 316  *  |                           0                          |  success
 317  *  +------------------------------------------------------+
 318  *
 319  *   30 29                                                0
 320  *  +--+---------------------------------------------------+
 321  *  | 0|                    errno value                    |  errno value
 322  *  +--+---------------------------------------------------+
 323  *
 324  *   30 29   26 25            16 15                       0
 325  *  +--+-------+----------------+--------------------------+
 326  *  | 1|   0   |      type      |           code           |  standard OpenFlow
 327  *  +--+-------+----------------+--------------------------+  error
 328  *
 329  *   30 29   26 25            16 15                       0
 330  *  +--+-------+----------------+--------------------------+  Nicira
 331  *  | 1| vendor|      type      |           code           |  NXET_VENDOR
 332  *  +--+-------+----------------+--------------------------+  error extension
 333  *
 334  * C and POSIX say that errno values are positive.  We assume that they are
 335  * less than 2**29.  They are actually less than 65536 on at least Linux,
 336  * FreeBSD, OpenBSD, and Windows.
 337  *
 338  * The 'vendor' field holds one of the OFPUTIL_VENDOR_* codes defined above.
 339  * It must be nonzero.
 340  *
 341  * Negative values are not defined.
 342  */
 343
 344 /* Currently 4 bits are allocated to the "vendor" field.  Make sure that all
 345  * the vendor codes can fit. */
 346 BUILD_ASSERT_DECL(OFPUTIL_N_VENDORS <= 16);
 347
 348 /* These are macro versions of the functions defined below.  The macro versions
 349  * are intended for use in contexts where function calls are not allowed,
 350  * e.g. static initializers and case labels. */
 351 #define OFP_MKERR(TYPE, CODE) ((1 << 30) | ((TYPE) << 16) | (CODE))
 352 #define OFP_MKERR_VENDOR(VENDOR, TYPE, CODE) \
 353         ((1 << 30) | ((VENDOR) << 26) | ((TYPE) << 16) | (CODE))
 354 #define OFP_MKERR_NICIRA(TYPE, CODE) \
 355         OFP_MKERR_VENDOR(OFPUTIL_VENDOR_NICIRA, TYPE, CODE)
 356
 357 /* Returns the standard OpenFlow error with the specified 'type' and 'code' as
 358  * an integer. */
 359 static inline int
 360 ofp_mkerr(uint16_t type, uint16_t code)
 361 {
 362     return OFP_MKERR(type, code);
 363 }
 364
 365 /* Returns the OpenFlow vendor error with the specified 'vendor', 'type', and
 366  * 'code' as an integer.  'vendor' must be an OFPUTIL_VENDOR_* constant. */
 367 static inline int
 368 ofp_mkerr_vendor(uint8_t vendor, uint16_t type, uint16_t code)
 369 {
 370     assert(vendor < OFPUTIL_N_VENDORS);
 371     return OFP_MKERR_VENDOR(vendor, type, code);
 372 }
 373
 374 /* Returns the OpenFlow vendor error with Nicira as vendor, with the specific
 375  * 'type' and 'code', as an integer. */
 376 static inline int
 377 ofp_mkerr_nicira(uint16_t type, uint16_t code)
 378 {
 379     return OFP_MKERR_NICIRA(type, code);
 380 }
 381
 382 /* Returns true if 'error' encodes an OpenFlow standard or vendor extension
 383  * error codes as documented above. */
 384 static inline bool
 385 is_ofp_error(int error)
 386 {
 387     return (error & (1 << 30)) != 0;
 388 }
 389
 390 /* Returns true if 'error' appears to be a system errno value. */
 391 static inline bool
 392 is_errno(int error)
 393 {
 394     return !is_ofp_error(error);
 395 }
 396
 397 /* Returns the "vendor" part of the OpenFlow error code 'error' (which must be
 398  * in the format explained above).  This is normally one of the
 399  * OFPUTIL_VENDOR_* constants.  Returns OFPUTIL_VENDOR_OPENFLOW (0) for a
 400  * standard OpenFlow error. */
 401 static inline uint8_t
 402 get_ofp_err_vendor(int error)
 403 {
 404     return (error >> 26) & 0xf;
 405 }
 406
 407 /* Returns the "type" part of the OpenFlow error code 'error' (which must be in
 408  * the format explained above). */
 409 static inline uint16_t
 410 get_ofp_err_type(int error)
 411 {
 412     return (error >> 16) & 0x3ff;
 413 }
 414
 415 /* Returns the "code" part of the OpenFlow error code 'error' (which must be in
 416  * the format explained above). */
 417 static inline uint16_t
 418 get_ofp_err_code(int error)
 419 {
 420     return error & 0xffff;
 421 }
 422
 423 struct ofpbuf *ofputil_encode_error_msg(int error, const struct ofp_header *);
 424 int ofputil_decode_error_msg(const struct ofp_header *, size_t *payload_ofs);
 425
 426 /* String versions of errors. */
 427 void ofputil_format_error(struct ds *, int error);
 428 char *ofputil_error_to_string(int error);
 429
 430 #endif /* ofp-util.h */