lib/ofp-util.h

   1 /*
   2  * Copyright (c) 2008, 2009, 2010 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_STATUS_REQUEST,
  75     OFPUTIL_NXT_STATUS_REPLY,
  76     OFPUTIL_NXT_TUN_ID_FROM_COOKIE,
  77     OFPUTIL_NXT_ROLE_REQUEST,
  78     OFPUTIL_NXT_ROLE_REPLY,
  79     OFPUTIL_NXT_SET_FLOW_FORMAT,
  80     OFPUTIL_NXT_FLOW_MOD,
  81     OFPUTIL_NXT_FLOW_REMOVED,
  82
  83     /* NXST_* stat requests. */
  84     OFPUTIL_NXST_FLOW_REQUEST,
  85     OFPUTIL_NXST_AGGREGATE_REQUEST,
  86
  87     /* NXST_* stat replies. */
  88     OFPUTIL_NXST_FLOW_REPLY,
  89     OFPUTIL_NXST_AGGREGATE_REPLY
  90 };
  91
  92 struct ofputil_msg_type;
  93 int ofputil_decode_msg_type(const struct ofp_header *,
  94                             const struct ofputil_msg_type **);
  95 enum ofputil_msg_code ofputil_msg_type_code(const struct ofputil_msg_type *);
  96 const char *ofputil_msg_type_name(const struct ofputil_msg_type *);
  97
  98 /* Converting OFPFW_NW_SRC_MASK and OFPFW_NW_DST_MASK wildcard bit counts to
  99  * and from IP bitmasks. */
 100 ovs_be32 ofputil_wcbits_to_netmask(int wcbits);
 101 int ofputil_netmask_to_wcbits(ovs_be32 netmask);
 102
 103 /* Work with OpenFlow 1.0 ofp_match. */
 104 void ofputil_cls_rule_from_match(const struct ofp_match *,
 105                                  unsigned int priority, enum nx_flow_format,
 106                                  ovs_be64 cookie, struct cls_rule *);
 107 void ofputil_cls_rule_to_match(const struct cls_rule *, enum nx_flow_format,
 108                                struct ofp_match *,
 109                                ovs_be64 cookie_in, ovs_be64 *cookie_out);
 110 void normalize_match(struct ofp_match *);
 111 char *ofp_match_to_literal_string(const struct ofp_match *match);
 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                                             bool cookie_support,
 119                                             ovs_be64 cookie);
 120
 121 struct ofpbuf *ofputil_make_set_flow_format(enum nx_flow_format);
 122
 123 /* Flow format independent flow_mod. */
 124 struct flow_mod {
 125     struct cls_rule cr;
 126     ovs_be64 cookie;
 127     uint16_t command;
 128     uint16_t idle_timeout;
 129     uint16_t hard_timeout;
 130     uint32_t buffer_id;
 131     uint16_t out_port;
 132     uint16_t flags;
 133     union ofp_action *actions;
 134     size_t n_actions;
 135 };
 136
 137 int ofputil_decode_flow_mod(struct flow_mod *, const struct ofp_header *,
 138                             enum nx_flow_format);
 139 struct ofpbuf *ofputil_encode_flow_mod(const struct flow_mod *,
 140                                        enum nx_flow_format);
 141
 142 /* Flow stats or aggregate stats request, independent of flow format. */
 143 struct flow_stats_request {
 144     bool aggregate;             /* Aggregate results? */
 145     struct cls_rule match;
 146     uint16_t out_port;
 147     uint8_t table_id;
 148 };
 149
 150 int ofputil_decode_flow_stats_request(struct flow_stats_request *,
 151                                       const struct ofp_header *,
 152                                       enum nx_flow_format);
 153 struct ofpbuf *ofputil_encode_flow_stats_request(
 154     const struct flow_stats_request *, enum nx_flow_format);
 155
 156 /* Flow removed message, independent of flow format. */
 157 struct ofputil_flow_removed {
 158     struct cls_rule rule;
 159     ovs_be64 cookie;
 160     uint8_t reason;             /* One of OFPRR_*. */
 161     uint32_t duration_sec;
 162     uint32_t duration_nsec;
 163     uint16_t idle_timeout;
 164     uint64_t packet_count;
 165     uint64_t byte_count;
 166 };
 167
 168 int ofputil_decode_flow_removed(struct ofputil_flow_removed *,
 169                                 const struct ofp_header *,
 170                                 enum nx_flow_format);
 171
 172 /* OpenFlow protocol utility functions. */
 173 void *make_openflow(size_t openflow_len, uint8_t type, struct ofpbuf **);
 174 void *make_nxmsg(size_t openflow_len, uint32_t subtype, struct ofpbuf **);
 175
 176 void *make_openflow_xid(size_t openflow_len, uint8_t type,
 177                         ovs_be32 xid, struct ofpbuf **);
 178 void *make_nxmsg_xid(size_t openflow_len, uint32_t subtype, ovs_be32 xid,
 179                      struct ofpbuf **);
 180
 181 void *put_openflow(size_t openflow_len, uint8_t type, struct ofpbuf *);
 182 void *put_openflow_xid(size_t openflow_len, uint8_t type, ovs_be32 xid,
 183                        struct ofpbuf *);
 184
 185 void *put_nxmsg(size_t openflow_len, uint32_t subtype, struct ofpbuf *);
 186 void *put_nxmsg_xid(size_t openflow_len, uint32_t subtype, ovs_be32 xid,
 187                     struct ofpbuf *);
 188
 189 void update_openflow_length(struct ofpbuf *);
 190
 191 void *ofputil_make_stats_request(size_t body_len, uint16_t type,
 192                                  struct ofpbuf **);
 193 void *ofputil_make_nxstats_request(size_t openflow_len, uint32_t subtype,
 194                                    struct ofpbuf **);
 195
 196 const void *ofputil_stats_body(const struct ofp_header *);
 197 size_t ofputil_stats_body_len(const struct ofp_header *);
 198
 199 const void *ofputil_nxstats_body(const struct ofp_header *);
 200 size_t ofputil_nxstats_body_len(const struct ofp_header *);
 201
 202 struct ofpbuf *make_flow_mod(uint16_t command, const struct cls_rule *,
 203                              size_t actions_len);
 204 struct ofpbuf *make_add_flow(const struct cls_rule *, uint32_t buffer_id,
 205                              uint16_t max_idle, size_t actions_len);
 206 struct ofpbuf *make_del_flow(const struct cls_rule *);
 207 struct ofpbuf *make_add_simple_flow(const struct cls_rule *,
 208                                     uint32_t buffer_id, uint16_t out_port,
 209                                     uint16_t max_idle);
 210 struct ofpbuf *make_packet_in(uint32_t buffer_id, uint16_t in_port,
 211                               uint8_t reason,
 212                               const struct ofpbuf *payload, int max_send_len);
 213 struct ofpbuf *make_packet_out(const struct ofpbuf *packet, uint32_t buffer_id,
 214                                uint16_t in_port,
 215                                const struct ofp_action_header *,
 216                                size_t n_actions);
 217 struct ofpbuf *make_buffered_packet_out(uint32_t buffer_id,
 218                                         uint16_t in_port, uint16_t out_port);
 219 struct ofpbuf *make_unbuffered_packet_out(const struct ofpbuf *packet,
 220                                           uint16_t in_port, uint16_t out_port);
 221 struct ofpbuf *make_echo_request(void);
 222 struct ofpbuf *make_echo_reply(const struct ofp_header *rq);
 223
 224 struct flow_stats_iterator {
 225     const uint8_t *pos, *end;
 226 };
 227 const struct ofp_flow_stats *flow_stats_first(struct flow_stats_iterator *,
 228                                               const struct ofp_stats_reply *);
 229 const struct ofp_flow_stats *flow_stats_next(struct flow_stats_iterator *);
 230 \f
 231 /* Actions. */
 232
 233 #define OFP_ACTION_ALIGN 8      /* Alignment of ofp_actions. */
 234
 235 struct actions_iterator {
 236     const union ofp_action *pos, *end;
 237 };
 238 const union ofp_action *actions_first(struct actions_iterator *,
 239                                       const union ofp_action *,
 240                                       size_t n_actions);
 241 const union ofp_action *actions_next(struct actions_iterator *);
 242
 243 int validate_actions(const union ofp_action *, size_t n_actions,
 244                      const struct flow *, int max_ports);
 245 bool action_outputs_to_port(const union ofp_action *, uint16_t port);
 246
 247 int ofputil_pull_actions(struct ofpbuf *, unsigned int actions_len,
 248                          union ofp_action **, size_t *);
 249 \f
 250 /* OpenFlow vendors.
 251  *
 252  * These functions map OpenFlow 32-bit vendor IDs (as used in struct
 253  * ofp_vendor_header) into 4-bit values to embed in an "int".  The 4-bit values
 254  * are only used internally in Open vSwitch and never appear on the wire, so
 255  * particular codes used are not important.
 256  */
 257
 258 /* Vendor error numbers currently used in Open vSwitch. */
 259 #define OFPUTIL_VENDORS                                     \
 260     /*             vendor name              vendor value */ \
 261     OFPUTIL_VENDOR(OFPUTIL_VENDOR_OPENFLOW, 0x00000000)     \
 262     OFPUTIL_VENDOR(OFPUTIL_VENDOR_NICIRA,   NX_VENDOR_ID)
 263
 264 /* OFPUTIL_VENDOR_* definitions. */
 265 enum ofputil_vendor_codes {
 266 #define OFPUTIL_VENDOR(NAME, VENDOR_ID) NAME,
 267     OFPUTIL_VENDORS
 268     OFPUTIL_N_VENDORS
 269 #undef OFPUTIL_VENDOR
 270 };
 271 \f
 272 /* Error codes.
 273  *
 274  * We embed system errno values and OpenFlow standard and vendor extension
 275  * error codes into a single 31-bit space using the following encoding.
 276  * (Bit 31 is unused and assumed 0 to avoid negative "int" values.)
 277  *
 278  *   30                                                   0
 279  *  +------------------------------------------------------+
 280  *  |                           0                          |  success
 281  *  +------------------------------------------------------+
 282  *
 283  *   30 29                                                0
 284  *  +--+---------------------------------------------------+
 285  *  | 0|                    errno value                    |  errno value
 286  *  +--+---------------------------------------------------+
 287  *
 288  *   30 29   26 25            16 15                       0
 289  *  +--+-------+----------------+--------------------------+
 290  *  | 1|   0   |      type      |           code           |  standard OpenFlow
 291  *  +--+-------+----------------+--------------------------+  error
 292  *
 293  *   30 29   26 25            16 15                       0
 294  *  +--+-------+----------------+--------------------------+  Nicira
 295  *  | 1| vendor|      type      |           code           |  NXET_VENDOR
 296  *  +--+-------+----------------+--------------------------+  error extension
 297  *
 298  * C and POSIX say that errno values are positive.  We assume that they are
 299  * less than 2**29.  They are actually less than 65536 on at least Linux,
 300  * FreeBSD, OpenBSD, and Windows.
 301  *
 302  * The 'vendor' field holds one of the OFPUTIL_VENDOR_* codes defined above.
 303  * It must be nonzero.
 304  *
 305  * Negative values are not defined.
 306  */
 307
 308 /* Currently 4 bits are allocated to the "vendor" field.  Make sure that all
 309  * the vendor codes can fit. */
 310 BUILD_ASSERT_DECL(OFPUTIL_N_VENDORS <= 16);
 311
 312 /* These are macro versions of the functions defined below.  The macro versions
 313  * are intended for use in contexts where function calls are not allowed,
 314  * e.g. static initializers and case labels. */
 315 #define OFP_MKERR(TYPE, CODE) ((1 << 30) | ((TYPE) << 16) | (CODE))
 316 #define OFP_MKERR_VENDOR(VENDOR, TYPE, CODE) \
 317         ((1 << 30) | ((VENDOR) << 26) | ((TYPE) << 16) | (CODE))
 318 #define OFP_MKERR_NICIRA(TYPE, CODE) \
 319         OFP_MKERR_VENDOR(OFPUTIL_VENDOR_NICIRA, TYPE, CODE)
 320
 321 /* Returns the standard OpenFlow error with the specified 'type' and 'code' as
 322  * an integer. */
 323 static inline int
 324 ofp_mkerr(uint16_t type, uint16_t code)
 325 {
 326     return OFP_MKERR(type, code);
 327 }
 328
 329 /* Returns the OpenFlow vendor error with the specified 'vendor', 'type', and
 330  * 'code' as an integer.  'vendor' must be an OFPUTIL_VENDOR_* constant. */
 331 static inline int
 332 ofp_mkerr_vendor(uint8_t vendor, uint16_t type, uint16_t code)
 333 {
 334     assert(vendor < OFPUTIL_N_VENDORS);
 335     return OFP_MKERR_VENDOR(vendor, type, code);
 336 }
 337
 338 /* Returns the OpenFlow vendor error with Nicira as vendor, with the specific
 339  * 'type' and 'code', as an integer. */
 340 static inline int
 341 ofp_mkerr_nicira(uint16_t type, uint16_t code)
 342 {
 343     return OFP_MKERR_NICIRA(type, code);
 344 }
 345
 346 /* Returns true if 'error' encodes an OpenFlow standard or vendor extension
 347  * error codes as documented above. */
 348 static inline bool
 349 is_ofp_error(int error)
 350 {
 351     return (error & (1 << 30)) != 0;
 352 }
 353
 354 /* Returns true if 'error' appears to be a system errno value. */
 355 static inline bool
 356 is_errno(int error)
 357 {
 358     return !is_ofp_error(error);
 359 }
 360
 361 /* Returns the "vendor" part of the OpenFlow error code 'error' (which must be
 362  * in the format explained above).  This is normally one of the
 363  * OFPUTIL_VENDOR_* constants.  Returns OFPUTIL_VENDOR_OPENFLOW (0) for a
 364  * standard OpenFlow error. */
 365 static inline uint8_t
 366 get_ofp_err_vendor(int error)
 367 {
 368     return (error >> 26) & 0xf;
 369 }
 370
 371 /* Returns the "type" part of the OpenFlow error code 'error' (which must be in
 372  * the format explained above). */
 373 static inline uint16_t
 374 get_ofp_err_type(int error)
 375 {
 376     return (error >> 16) & 0x3ff;
 377 }
 378
 379 /* Returns the "code" part of the OpenFlow error code 'error' (which must be in
 380  * the format explained above). */
 381 static inline uint16_t
 382 get_ofp_err_code(int error)
 383 {
 384     return error & 0xffff;
 385 }
 386
 387 struct ofpbuf *make_ofp_error_msg(int error, const struct ofp_header *);
 388
 389 #endif /* ofp-util.h */