lib/nx-match.h

   1 /*
   2  * Copyright (c) 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 NX_MATCH_H
  18 #define NX_MATCH_H 1
  19
  20 #include <stdint.h>
  21 #include <sys/types.h>
  22 #include <netinet/in.h>
  23 #include "openvswitch/types.h"
  24
  25 struct cls_rule;
  26 struct ds;
  27 struct flow;
  28 struct ofpbuf;
  29 struct nx_action_reg_load;
  30 struct nx_action_reg_move;
  31
  32 /* Nicira Extended Match (NXM) flexible flow match helper functions.
  33  *
  34  * See include/openflow/nicira-ext.h for NXM specification.
  35  */
  36
  37 int nx_pull_match(struct ofpbuf *, unsigned int match_len, uint16_t priority,
  38                   struct cls_rule *);
  39 int nx_put_match(struct ofpbuf *, const struct cls_rule *);
  40
  41 char *nx_match_to_string(const uint8_t *, unsigned int match_len);
  42 int nx_match_from_string(const char *, struct ofpbuf *);
  43
  44 void nxm_parse_reg_move(struct nx_action_reg_move *, const char *);
  45 void nxm_parse_reg_load(struct nx_action_reg_load *, const char *);
  46
  47 void nxm_format_reg_move(const struct nx_action_reg_move *, struct ds *);
  48 void nxm_format_reg_load(const struct nx_action_reg_load *, struct ds *);
  49
  50 int nxm_check_reg_move(const struct nx_action_reg_move *, const struct flow *);
  51 int nxm_check_reg_load(const struct nx_action_reg_load *, const struct flow *);
  52
  53 void nxm_execute_reg_move(const struct nx_action_reg_move *, struct flow *);
  54 void nxm_execute_reg_load(const struct nx_action_reg_load *, struct flow *);
  55
  56 /* Dealing with the 'ofs_nbits' members of struct nx_action_reg_load and struct
  57  * nx_action_multipath. */
  58
  59 static inline ovs_be16
  60 nxm_encode_ofs_nbits(int ofs, int n_bits)
  61 {
  62     return htons((ofs << 6) | (n_bits - 1));
  63 }
  64
  65 static inline int
  66 nxm_decode_ofs(ovs_be16 ofs_nbits)
  67 {
  68     return ntohs(ofs_nbits) >> 6;
  69 }
  70
  71 static inline int
  72 nxm_decode_n_bits(ovs_be16 ofs_nbits)
  73 {
  74     return (ntohs(ofs_nbits) & 0x3f) + 1;
  75 }
  76 \f
  77 /* Upper bound on the length of an nx_match.  The longest nx_match (assuming
  78  * we implement 4 registers) would be:
  79  *
  80  *                   header  value  mask  total
  81  *                   ------  -----  ----  -----
  82  *  NXM_OF_IN_PORT      4       2    --      6
  83  *  NXM_OF_ETH_DST_W    4       6     6     16
  84  *  NXM_OF_ETH_SRC      4       6    --     10
  85  *  NXM_OF_ETH_TYPE     4       2    --      6
  86  *  NXM_OF_VLAN_TCI     4       2     2      8
  87  *  NXM_OF_IP_TOS       4       1    --      5
  88  *  NXM_OF_IP_PROTO     4       2    --      6
  89  *  NXM_OF_IP_SRC_W     4       4     4     12
  90  *  NXM_OF_IP_DST_W     4       4     4     12
  91  *  NXM_OF_TCP_SRC      4       2    --      6
  92  *  NXM_OF_TCP_DST      4       2    --      6
  93  *  NXM_NX_REG_W(0)     4       4     4     12
  94  *  NXM_NX_REG_W(1)     4       4     4     12
  95  *  NXM_NX_REG_W(2)     4       4     4     12
  96  *  NXM_NX_REG_W(3)     4       4     4     12
  97  *  NXM_NX_TUN_ID_W     4       8     8     20
  98  *  -------------------------------------------
  99  *  total                                  161
 100  *
 101  * So this value is conservative.
 102  */
 103 #define NXM_MAX_LEN 192
 104
 105 /* This is my guess at the length of a "typical" nx_match, for use in
 106  * predicting space requirements. */
 107 #define NXM_TYPICAL_LEN 64
 108
 109 #endif /* nx-match.h */