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