Line data    Source code

       1             : /*
       2             :  * MPLS packet format
       3             :  *
       4             :  * Copyright (c) 2012 Cisco and/or its affiliates.
       5             :  * Licensed under the Apache License, Version 2.0 (the "License");
       6             :  * you may not use this file except in compliance with the License.
       7             :  * You may obtain a copy of the License at:
       8             :  *
       9             :  *     http://www.apache.org/licenses/LICENSE-2.0
      10             :  *
      11             :  * Unless required by applicable law or agreed to in writing, software
      12             :  * distributed under the License is distributed on an "AS IS" BASIS,
      13             :  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
      14             :  * See the License for the specific language governing permissions and
      15             :  * limitations under the License.
      16             :  */
      17             : 
      18             : #ifndef included_vnet_mpls_packet_h
      19             : #define included_vnet_mpls_packet_h
      20             : 
      21             : #include <vnet/ip/ip_packet.h>
      22             : 
      23             : /**
      24             :  * A label value only, i.e. 20bits.
      25             :  */
      26             : typedef u32 mpls_label_t;
      27             : 
      28             : typedef struct {
      29             :     /* Label: top 20 bits [in network byte order] */
      30             :     /* Experimental: 3 bits ... */
      31             :     /* S (bottom of label stack): 1 bit */
      32             :     /* TTL: 8 bits */
      33             :     mpls_label_t label_exp_s_ttl;
      34             : } mpls_unicast_header_t;
      35             : 
      36             : typedef enum mpls_eos_bit_t_
      37             : {
      38             :     MPLS_NON_EOS = 0,
      39             :     MPLS_EOS     = 1,
      40             : } mpls_eos_bit_t;
      41             : 
      42             : #define MPLS_EOS_BITS {                         \
      43             :     [MPLS_NON_EOS] = "neos",                  \
      44             :     [MPLS_EOS] = "eos",                               \
      45             : }
      46             : 
      47             : /**
      48             :  * The Default TTL added to MPLS label headers when no other value is available
      49             :  */
      50             : #define MPLS_LABEL_DEFAULT_TTL 64
      51             : 
      52             : /**
      53             :  * The Default EXP added to MPLS label headers when no other value is available
      54             :  */
      55             : #define MPLS_LABEL_DEFAULT_EXP 0
      56             : 
      57             : /**
      58             :  * When in uniform mode convert an IPv[46] DSCP value to an MPLS EXP value
      59             :  */
      60         771 : static inline u8 ip_dscp_to_mpls_exp (ip_dscp_t tos)
      61             : {
      62         771 :     return (tos >> 5);
      63             : }
      64             : 
      65             : /**
      66             :  * When in uniform mode convert an MPLS EXP value to an IPv[46] DSCP value
      67             :  */
      68         771 : static inline u8 mpls_exp_to_ip_dscp (u8 exp)
      69             : {
      70         771 :     return (exp << 5);
      71             : }
      72             : 
      73             : #define FOR_EACH_MPLS_EOS_BIT(_eos) \
      74             :     for (_eos = MPLS_NON_EOS; _eos <= MPLS_EOS; _eos++)
      75             : 
      76             : #define MPLS_ENTRY_LABEL_OFFSET        0
      77             : #define MPLS_ENTRY_LABEL_SHIFT 12
      78             : #define MPLS_ENTRY_LABEL_MASK  0x000fffff
      79             : #define MPLS_ENTRY_LABEL_BITS  \
      80             :     (MPLS_ENTRY_LABEL_MASK << MPLS_ENTRY_LABEL_SHIFT)
      81             : 
      82             : #define MPLS_ENTRY_EXP_OFFSET   2       /* byte offset to EXP bits */
      83             : #define MPLS_ENTRY_EXP_SHIFT   9
      84             : #define MPLS_ENTRY_EXP_MASK    0x07
      85             : #define MPLS_ENTRY_EXP(mpls)   \
      86             :     (((mpls)>>MPLS_ENTRY_EXP_SHIFT) & MPLS_ENTRY_EXP_MASK)
      87             : #define MPLS_ENTRY_EXP_BITS    \
      88             :     (MPLS_ENTRY_EXP_MASK << MPLS_ENTRY_EXP_SHIFT)
      89             : 
      90             : #define MPLS_ENTRY_EOS_OFFSET   2       /* byte offset to EOS bit */
      91             : #define MPLS_ENTRY_EOS_SHIFT   8
      92             : #define MPLS_ENTRY_EOS_MASK    0x01    /* EOS bit in its byte */
      93             : #define        MPLS_ENTRY_EOS(mpls)    \
      94             :     (((mpls) >> MPLS_ENTRY_EOS_SHIFT) & MPLS_ENTRY_EOS_MASK)
      95             : #define MPLS_ENTRY_EOS_BIT     (MPLS_ENTRY_EOS_MASK << MPLS_ENTRY_EOS_SHIFT)
      96             : 
      97             : #define MPLS_ENTRY_TTL_OFFSET  3  /* byte offset to ttl field */
      98             : #define MPLS_ENTRY_TTL_SHIFT   0
      99             : #define MPLS_ENTRY_TTL_MASK    0xff
     100             : #define MPLS_ENTRY_TTL(mpls)   \
     101             :     (((mpls) >> MPLS_ENTRY_TTL_SHIFT) & MPLS_ENTRY_TTL_MASK)
     102             : #define MPLS_ENTRY_TTL_BITS    \
     103             :     (MPLS_ENTRY_TTL_MASK << MPLS_ENTRY_TTL_SHIFT)
     104             : 
     105       48821 : static inline u32 vnet_mpls_uc_get_label (mpls_label_t label_exp_s_ttl)
     106             : {
     107       48821 :     return (label_exp_s_ttl>>MPLS_ENTRY_LABEL_SHIFT);
     108             : }
     109             : 
     110       29334 : static inline u32 vnet_mpls_uc_get_exp (mpls_label_t label_exp_s_ttl)
     111             : {
     112       29334 :     return (MPLS_ENTRY_EXP(label_exp_s_ttl));
     113             : }
     114             : 
     115       43374 : static inline u32 vnet_mpls_uc_get_s (mpls_label_t label_exp_s_ttl)
     116             : {
     117       43374 :     return (MPLS_ENTRY_EOS(label_exp_s_ttl));
     118             : }
     119             : 
     120       29201 : static inline u32 vnet_mpls_uc_get_ttl (mpls_label_t label_exp_s_ttl)
     121             : {
     122       29201 :     return (MPLS_ENTRY_TTL(label_exp_s_ttl));
     123             : }
     124             : 
     125        2219 : static inline void vnet_mpls_uc_set_label (mpls_label_t *label_exp_s_ttl,
     126             :                                            u32 value)
     127             : {
     128        2219 :     *label_exp_s_ttl = (((*label_exp_s_ttl) & ~(MPLS_ENTRY_LABEL_BITS)) |
     129        2219 :                         ((value  & MPLS_ENTRY_LABEL_MASK) << MPLS_ENTRY_LABEL_SHIFT));
     130        2219 : }
     131             : 
     132        2199 : static inline void vnet_mpls_uc_set_exp (mpls_label_t *label_exp_s_ttl,
     133             :                                          u32 exp)
     134             : {
     135        2199 :     *label_exp_s_ttl = (((*label_exp_s_ttl) & ~(MPLS_ENTRY_EXP_BITS)) |
     136        2199 :                         ((exp & MPLS_ENTRY_EXP_MASK) << MPLS_ENTRY_EXP_SHIFT));
     137        2199 : }
     138             :  
     139        2219 : static inline void vnet_mpls_uc_set_s (mpls_label_t *label_exp_s_ttl,
     140             :                                        u32 eos)
     141             : {
     142        2219 :     *label_exp_s_ttl = (((*label_exp_s_ttl) & ~(MPLS_ENTRY_EOS_BIT)) |
     143        2219 :                         ((eos & MPLS_ENTRY_EOS_MASK) << MPLS_ENTRY_EOS_SHIFT));
     144        2219 : }
     145             :  
     146        2199 : static inline void vnet_mpls_uc_set_ttl (mpls_label_t *label_exp_s_ttl,
     147             :                                          u32 ttl)
     148             : {
     149        2199 :     *label_exp_s_ttl = (((*label_exp_s_ttl) & ~(MPLS_ENTRY_TTL_BITS)) |
     150        2199 :                         ((ttl & MPLS_ENTRY_TTL_MASK)));
     151        2199 : }
     152             : 
     153             : #endif /* included_vnet_mpls_packet_h */