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_ROLE_REQUEST,
  75     OFPUTIL_NXT_ROLE_REPLY,
  76     OFPUTIL_NXT_SET_FLOW_FORMAT,
  77     OFPUTIL_NXT_FLOW_MOD,
  78     OFPUTIL_NXT_FLOW_REMOVED,
  79
  80     /* NXST_* stat requests. */
  81     OFPUTIL_NXST_FLOW_REQUEST,
  82     OFPUTIL_NXST_AGGREGATE_REQUEST,
  83
  84     /* NXST_* stat replies. */
  85     OFPUTIL_NXST_FLOW_REPLY,
  86     OFPUTIL_NXST_AGGREGATE_REPLY
  87 };
  88
  89 struct ofputil_msg_type;
  90 int ofputil_decode_msg_type(const struct ofp_header *,
  91                             const struct ofputil_msg_type **);
  92 enum ofputil_msg_code ofputil_msg_type_code(const struct ofputil_msg_type *);
  93 const char *ofputil_msg_type_name(const struct ofputil_msg_type *);
  94
  95 /* Converting OFPFW_NW_SRC_MASK and OFPFW_NW_DST_MASK wildcard bit counts to
  96  * and from IP bitmasks. */
  97 ovs_be32 ofputil_wcbits_to_netmask(int wcbits);
  98 int ofputil_netmask_to_wcbits(ovs_be32 netmask);
  99
 100 /* Work with OpenFlow 1.0 ofp_match. */
 101 void ofputil_cls_rule_from_match(const struct ofp_match *,
 102                                  unsigned int priority, struct cls_rule *);
 103 void ofputil_cls_rule_to_match(const struct cls_rule *, struct ofp_match *);
 104
 105 /* dl_type translation between OpenFlow and 'struct flow' format. */
 106 ovs_be16 ofputil_dl_type_to_openflow(ovs_be16 flow_dl_type);
 107 ovs_be16 ofputil_dl_type_from_openflow(ovs_be16 ofp_dl_type);
 108
 109 /* Flow formats. */
 110 bool ofputil_flow_format_is_valid(enum nx_flow_format);
 111 const char *ofputil_flow_format_to_string(enum nx_flow_format);
 112 int ofputil_flow_format_from_string(const char *);
 113 enum nx_flow_format ofputil_min_flow_format(const struct cls_rule *);
 114
 115 struct ofpbuf *ofputil_make_set_flow_format(enum nx_flow_format);
 116
 117 /* Flow format independent flow_mod. */
 118 struct flow_mod {
 119     struct cls_rule cr;
 120     ovs_be64 cookie;
 121     uint16_t command;
 122     uint16_t idle_timeout;
 123     uint16_t hard_timeout;
 124     uint32_t buffer_id;
 125     uint16_t out_port;
 126     uint16_t flags;
 127     union ofp_action *actions;
 128     size_t n_actions;
 129 };
 130
 131 int ofputil_decode_flow_mod(struct flow_mod *, const struct ofp_header *);
 132 struct ofpbuf *ofputil_encode_flow_mod(const struct flow_mod *,
 133                                        enum nx_flow_format);
 134
 135 /* Flow stats or aggregate stats request, independent of flow format. */
 136 struct flow_stats_request {
 137     bool aggregate;             /* Aggregate results? */
 138     struct cls_rule match;
 139     uint16_t out_port;
 140     uint8_t table_id;
 141 };
 142
 143 int ofputil_decode_flow_stats_request(struct flow_stats_request *,
 144                                       const struct ofp_header *);
 145 struct ofpbuf *ofputil_encode_flow_stats_request(
 146     const struct flow_stats_request *, enum nx_flow_format);
 147
 148 /* Flow stats reply, independent of flow format. */
 149 struct ofputil_flow_stats {
 150     struct cls_rule rule;
 151     ovs_be64 cookie;
 152     uint8_t table_id;
 153     uint32_t duration_sec;
 154     uint32_t duration_nsec;
 155     uint16_t idle_timeout;
 156     uint16_t hard_timeout;
 157     uint64_t packet_count;
 158     uint64_t byte_count;
 159     union ofp_action *actions;
 160     size_t n_actions;
 161 };
 162
 163 int ofputil_decode_flow_stats_reply(struct ofputil_flow_stats *,
 164                                     struct ofpbuf *msg);
 165
 166 /* Flow removed message, independent of flow format. */
 167 struct ofputil_flow_removed {
 168     struct cls_rule rule;
 169     ovs_be64 cookie;
 170     uint8_t reason;             /* One of OFPRR_*. */
 171     uint32_t duration_sec;
 172     uint32_t duration_nsec;
 173     uint16_t idle_timeout;
 174     uint64_t packet_count;
 175     uint64_t byte_count;
 176 };
 177
 178 int ofputil_decode_flow_removed(struct ofputil_flow_removed *,
 179                                 const struct ofp_header *);
 180 struct ofpbuf *ofputil_encode_flow_removed(const struct ofputil_flow_removed *,
 181                                            enum nx_flow_format);
 182
 183 /* Abstract packet-in message. */
 184 struct ofputil_packet_in {
 185     struct ofpbuf *packet;
 186     uint16_t in_port;
 187     uint8_t reason;             /* One of OFPR_*. */
 188
 189     uint32_t buffer_id;
 190     int send_len;
 191 };
 192
 193 struct ofpbuf *ofputil_encode_packet_in(const struct ofputil_packet_in *,
 194                                         struct ofpbuf *rw_packet);
 195
 196 /* OpenFlow protocol utility functions. */
 197 void *make_openflow(size_t openflow_len, uint8_t type, struct ofpbuf **);
 198 void *make_nxmsg(size_t openflow_len, uint32_t subtype, struct ofpbuf **);
 199
 200 void *make_openflow_xid(size_t openflow_len, uint8_t type,
 201                         ovs_be32 xid, struct ofpbuf **);
 202 void *make_nxmsg_xid(size_t openflow_len, uint32_t subtype, ovs_be32 xid,
 203                      struct ofpbuf **);
 204
 205 void *put_openflow(size_t openflow_len, uint8_t type, struct ofpbuf *);
 206 void *put_openflow_xid(size_t openflow_len, uint8_t type, ovs_be32 xid,
 207                        struct ofpbuf *);
 208
 209 void *put_nxmsg(size_t openflow_len, uint32_t subtype, struct ofpbuf *);
 210 void *put_nxmsg_xid(size_t openflow_len, uint32_t subtype, ovs_be32 xid,
 211                     struct ofpbuf *);
 212
 213 void update_openflow_length(struct ofpbuf *);
 214
 215 void *ofputil_make_stats_request(size_t body_len, uint16_t type,
 216                                  struct ofpbuf **);
 217 void *ofputil_make_nxstats_request(size_t openflow_len, uint32_t subtype,
 218                                    struct ofpbuf **);
 219
 220 const void *ofputil_stats_body(const struct ofp_header *);
 221 size_t ofputil_stats_body_len(const struct ofp_header *);
 222
 223 const void *ofputil_nxstats_body(const struct ofp_header *);
 224 size_t ofputil_nxstats_body_len(const struct ofp_header *);
 225
 226 struct ofpbuf *make_flow_mod(uint16_t command, const struct cls_rule *,
 227                              size_t actions_len);
 228 struct ofpbuf *make_add_flow(const struct cls_rule *, uint32_t buffer_id,
 229                              uint16_t max_idle, size_t actions_len);
 230 struct ofpbuf *make_del_flow(const struct cls_rule *);
 231 struct ofpbuf *make_add_simple_flow(const struct cls_rule *,
 232                                     uint32_t buffer_id, uint16_t out_port,
 233                                     uint16_t max_idle);
 234 struct ofpbuf *make_packet_in(uint32_t buffer_id, uint16_t in_port,
 235                               uint8_t reason,
 236                               const struct ofpbuf *payload, int max_send_len);
 237 struct ofpbuf *make_packet_out(const struct ofpbuf *packet, uint32_t buffer_id,
 238                                uint16_t in_port,
 239                                const struct ofp_action_header *,
 240                                size_t n_actions);
 241 struct ofpbuf *make_buffered_packet_out(uint32_t buffer_id,
 242                                         uint16_t in_port, uint16_t out_port);
 243 struct ofpbuf *make_unbuffered_packet_out(const struct ofpbuf *packet,
 244                                           uint16_t in_port, uint16_t out_port);
 245 struct ofpbuf *make_echo_request(void);
 246 struct ofpbuf *make_echo_reply(const struct ofp_header *rq);
 247 \f
 248 /* Actions. */
 249
 250 #define OFP_ACTION_ALIGN 8      /* Alignment of ofp_actions. */
 251
 252 struct actions_iterator {
 253     const union ofp_action *pos, *end;
 254 };
 255 const union ofp_action *actions_first(struct actions_iterator *,
 256                                       const union ofp_action *,
 257                                       size_t n_actions);
 258 const union ofp_action *actions_next(struct actions_iterator *);
 259
 260 int validate_actions(const union ofp_action *, size_t n_actions,
 261                      const struct flow *, int max_ports);
 262 bool action_outputs_to_port(const union ofp_action *, ovs_be16 port);
 263
 264 int ofputil_pull_actions(struct ofpbuf *, unsigned int actions_len,
 265                          union ofp_action **, size_t *);
 266 \f
 267 /* OpenFlow vendors.
 268  *
 269  * These functions map OpenFlow 32-bit vendor IDs (as used in struct
 270  * ofp_vendor_header) into 4-bit values to embed in an "int".  The 4-bit values
 271  * are only used internally in Open vSwitch and never appear on the wire, so
 272  * particular codes used are not important.
 273  */
 274
 275 /* Vendor error numbers currently used in Open vSwitch. */
 276 #define OFPUTIL_VENDORS                                     \
 277     /*             vendor name              vendor value */ \
 278     OFPUTIL_VENDOR(OFPUTIL_VENDOR_OPENFLOW, 0x00000000)     \
 279     OFPUTIL_VENDOR(OFPUTIL_VENDOR_NICIRA,   NX_VENDOR_ID)
 280
 281 /* OFPUTIL_VENDOR_* definitions. */
 282 enum ofputil_vendor_codes {
 283 #define OFPUTIL_VENDOR(NAME, VENDOR_ID) NAME,
 284     OFPUTIL_VENDORS
 285     OFPUTIL_N_VENDORS
 286 #undef OFPUTIL_VENDOR
 287 };
 288 \f
 289 /* Error codes.
 290  *
 291  * We embed system errno values and OpenFlow standard and vendor extension
 292  * error codes into a single 31-bit space using the following encoding.
 293  * (Bit 31 is unused and assumed 0 to avoid negative "int" values.)
 294  *
 295  *   30                                                   0
 296  *  +------------------------------------------------------+
 297  *  |                           0                          |  success
 298  *  +------------------------------------------------------+
 299  *
 300  *   30 29                                                0
 301  *  +--+---------------------------------------------------+
 302  *  | 0|                    errno value                    |  errno value
 303  *  +--+---------------------------------------------------+
 304  *
 305  *   30 29   26 25            16 15                       0
 306  *  +--+-------+----------------+--------------------------+
 307  *  | 1|   0   |      type      |           code           |  standard OpenFlow
 308  *  +--+-------+----------------+--------------------------+  error
 309  *
 310  *   30 29   26 25            16 15                       0
 311  *  +--+-------+----------------+--------------------------+  Nicira
 312  *  | 1| vendor|      type      |           code           |  NXET_VENDOR
 313  *  +--+-------+----------------+--------------------------+  error extension
 314  *
 315  * C and POSIX say that errno values are positive.  We assume that they are
 316  * less than 2**29.  They are actually less than 65536 on at least Linux,
 317  * FreeBSD, OpenBSD, and Windows.
 318  *
 319  * The 'vendor' field holds one of the OFPUTIL_VENDOR_* codes defined above.
 320  * It must be nonzero.
 321  *
 322  * Negative values are not defined.
 323  */
 324
 325 /* Currently 4 bits are allocated to the "vendor" field.  Make sure that all
 326  * the vendor codes can fit. */
 327 BUILD_ASSERT_DECL(OFPUTIL_N_VENDORS <= 16);
 328
 329 /* These are macro versions of the functions defined below.  The macro versions
 330  * are intended for use in contexts where function calls are not allowed,
 331  * e.g. static initializers and case labels. */
 332 #define OFP_MKERR(TYPE, CODE) ((1 << 30) | ((TYPE) << 16) | (CODE))
 333 #define OFP_MKERR_VENDOR(VENDOR, TYPE, CODE) \
 334         ((1 << 30) | ((VENDOR) << 26) | ((TYPE) << 16) | (CODE))
 335 #define OFP_MKERR_NICIRA(TYPE, CODE) \
 336         OFP_MKERR_VENDOR(OFPUTIL_VENDOR_NICIRA, TYPE, CODE)
 337
 338 /* Returns the standard OpenFlow error with the specified 'type' and 'code' as
 339  * an integer. */
 340 static inline int
 341 ofp_mkerr(uint16_t type, uint16_t code)
 342 {
 343     return OFP_MKERR(type, code);
 344 }
 345
 346 /* Returns the OpenFlow vendor error with the specified 'vendor', 'type', and
 347  * 'code' as an integer.  'vendor' must be an OFPUTIL_VENDOR_* constant. */
 348 static inline int
 349 ofp_mkerr_vendor(uint8_t vendor, uint16_t type, uint16_t code)
 350 {
 351     assert(vendor < OFPUTIL_N_VENDORS);
 352     return OFP_MKERR_VENDOR(vendor, type, code);
 353 }
 354
 355 /* Returns the OpenFlow vendor error with Nicira as vendor, with the specific
 356  * 'type' and 'code', as an integer. */
 357 static inline int
 358 ofp_mkerr_nicira(uint16_t type, uint16_t code)
 359 {
 360     return OFP_MKERR_NICIRA(type, code);
 361 }
 362
 363 /* Returns true if 'error' encodes an OpenFlow standard or vendor extension
 364  * error codes as documented above. */
 365 static inline bool
 366 is_ofp_error(int error)
 367 {
 368     return (error & (1 << 30)) != 0;
 369 }
 370
 371 /* Returns true if 'error' appears to be a system errno value. */
 372 static inline bool
 373 is_errno(int error)
 374 {
 375     return !is_ofp_error(error);
 376 }
 377
 378 /* Returns the "vendor" part of the OpenFlow error code 'error' (which must be
 379  * in the format explained above).  This is normally one of the
 380  * OFPUTIL_VENDOR_* constants.  Returns OFPUTIL_VENDOR_OPENFLOW (0) for a
 381  * standard OpenFlow error. */
 382 static inline uint8_t
 383 get_ofp_err_vendor(int error)
 384 {
 385     return (error >> 26) & 0xf;
 386 }
 387
 388 /* Returns the "type" part of the OpenFlow error code 'error' (which must be in
 389  * the format explained above). */
 390 static inline uint16_t
 391 get_ofp_err_type(int error)
 392 {
 393     return (error >> 16) & 0x3ff;
 394 }
 395
 396 /* Returns the "code" part of the OpenFlow error code 'error' (which must be in
 397  * the format explained above). */
 398 static inline uint16_t
 399 get_ofp_err_code(int error)
 400 {
 401     return error & 0xffff;
 402 }
 403
 404 struct ofpbuf *ofputil_encode_error_msg(int error, const struct ofp_header *);
 405 int ofputil_decode_error_msg(const struct ofp_header *, size_t *payload_ofs);
 406
 407 /* String versions of errors. */
 408 void ofputil_format_error(struct ds *, int error);
 409 char *ofputil_error_to_string(int error);
 410
 411 #endif /* ofp-util.h */