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 int nxm_field_bytes(uint32_t header);
  57 int nxm_field_bits(uint32_t header);
  58
  59 const char *nxm_parse_field_bits(const char *s,
  60                                  uint32_t *headerp, int *ofsp, int *n_bitsp);
  61 void nxm_format_field_bits(struct ds *, uint32_t header, int ofs, int n_bits);
  62
  63 /* Dealing with the 'ofs_nbits' members of struct nx_action_reg_load and struct
  64  * nx_action_multipath. */
  65
  66 static inline ovs_be16
  67 nxm_encode_ofs_nbits(int ofs, int n_bits)
  68 {
  69     return htons((ofs << 6) | (n_bits - 1));
  70 }
  71
  72 static inline int
  73 nxm_decode_ofs(ovs_be16 ofs_nbits)
  74 {
  75     return ntohs(ofs_nbits) >> 6;
  76 }
  77
  78 static inline int
  79 nxm_decode_n_bits(ovs_be16 ofs_nbits)
  80 {
  81     return (ntohs(ofs_nbits) & 0x3f) + 1;
  82 }
  83 \f
  84 /* Upper bound on the length of an nx_match.  The longest nx_match (assuming
  85  * we implement 4 registers) would be:
  86  *
  87  *                   header  value  mask  total
  88  *                   ------  -----  ----  -----
  89  *  NXM_OF_IN_PORT      4       2    --      6
  90  *  NXM_OF_ETH_DST_W    4       6     6     16
  91  *  NXM_OF_ETH_SRC      4       6    --     10
  92  *  NXM_OF_ETH_TYPE     4       2    --      6
  93  *  NXM_OF_VLAN_TCI     4       2     2      8
  94  *  NXM_OF_IP_TOS       4       1    --      5
  95  *  NXM_OF_IP_PROTO     4       2    --      6
  96  *  NXM_OF_IPV6_SRC_W   4      16    16     36
  97  *  NXM_OF_IPV6_DST_W   4      16    16     36
  98  *  NXM_OF_ICMP_TYPE    4       1    --      5
  99  *  NXM_OF_ICMP_CODE    4       1    --      5
 100  *  NXM_NX_ND_TARGET    4      16    --     20
 101  *  NXM_NX_ND_SLL       4       6    --     10
 102  *  NXM_NX_REG_W(0)     4       4     4     12
 103  *  NXM_NX_REG_W(1)     4       4     4     12
 104  *  NXM_NX_REG_W(2)     4       4     4     12
 105  *  NXM_NX_REG_W(3)     4       4     4     12
 106  *  NXM_NX_TUN_ID_W     4       8     8     20
 107  *  -------------------------------------------
 108  *  total                                  237
 109  *
 110  * So this value is conservative.
 111  */
 112 #define NXM_MAX_LEN 256
 113
 114 /* This is my guess at the length of a "typical" nx_match, for use in
 115  * predicting space requirements. */
 116 #define NXM_TYPICAL_LEN 64
 117
 118 #endif /* nx-match.h */