man/man8/tc-ife.8

   1 .TH "IFE action in tc" 8 "22 Apr 2016" "iproute2" "Linux"
   2
   3 .SH NAME
   4 IFE - encapsulate/decapsulate metadata
   5 .SH SYNOPSIS
   6 .in +8
   7 .ti -8
   8 .BR tc " ... " " action ife"
   9 .IR DIRECTION " [ " ACTION " ] "
  10 .RB "[ " dst
  11 .IR DMAC " ] "
  12 .RB "[ " src
  13 .IR SMAC " ] "
  14 .RB "[ " type
  15 .IR TYPE " ] "
  16 .RI "[ "
  17 .IR CONTROL " ] "
  18 .RB "[ " index
  19 .IR INDEX " ] "
  20
  21 .ti -8
  22 .IR DIRECTION " := { "
  23 .BR decode " | " encode " }"
  24
  25 .ti -8
  26 .IR ACTION " := { "
  27 .BI allow " ATTR"
  28 .RB "| " use
  29 .IR "ATTR value" " }"
  30
  31 .ti -8
  32 .IR ATTR " := { "
  33 .BR mark " | " prio " | " tcindex " }"
  34
  35 .ti -8
  36 .IR CONTROL " := { "
  37 .BR reclassify " | " use " | " pipe " | " drop " | " continue " | " ok " | " goto " " chain " " CHAIN_INDEX " }"
  38 .SH DESCRIPTION
  39 The
  40 .B ife
  41 action allows for a sending side to encapsulate arbitrary metadata, which is
  42 then decapsulated by the receiving end. The sender runs in encoding mode and
  43 the receiver in decode mode. Both sender and receiver must specify the same
  44 ethertype. In the future, a registered ethertype may be available as a default.
  45 .SH OPTIONS
  46 .TP
  47 .B decode
  48 For the receiving side; decode the metadata if the packet matches.
  49 .TP
  50 .B encode
  51 For the sending side. Encode the specified metadata if the packet matches.
  52 .TP
  53 .B allow
  54 Encode direction only. Allows encoding specified metadata.
  55 .TP
  56 .B use
  57 Encode direction only. Enforce static encoding of specified metadata.
  58 .TP
  59 .BR mark " [ "
  60 .IR u32_value " ]"
  61 The value to set for the skb mark. The u32 value is required only when
  62 .BR use " is specified. If
  63 .BR mark " value is zero, it will not be encoded, instead
  64 "overlimits" statistics increment and
  65 .BR CONTROL " action is taken.
  66 .TP
  67 .BR prio " [ "
  68 .IR u32_value " ]"
  69 The value to set for priority in the skb structure. The u32 value is required
  70 only when
  71 .BR use " is specified."
  72 .TP
  73 .BR tcindex " ["
  74 .IR u16_value " ]"
  75 Value to set for the traffic control index in the skb structure. The u16 value
  76 is required only when
  77 .BR use " is specified."
  78 .TP
  79 .BI dmac " DMAC"
  80 .TQ
  81 .BI smac " SMAC"
  82 Optional six byte destination or source MAC address to encode.
  83 .TP
  84 .BI type " TYPE"
  85 Optional 16-bit ethertype to encode.
  86 .TP
  87 .BI CONTROL
  88 Action to take following an encode/decode.
  89 .TP
  90 .BI index " INDEX"
  91 Assign a unique ID to this action instead of letting the kernel choose one
  92 automatically.
  93 .I INDEX
  94 is a 32bit unsigned integer greater than zero.
  95 .SH EXAMPLES
  96
  97 On the receiving side, match packets with ethertype 0xdead and restart
  98 classification so that it will match ICMP on the next rule, at prio 3:
  99 .RS
 100 .EX
 101 # tc qdisc add dev eth0 handle ffff: ingress
 102 # tc filter add dev eth0 parent ffff: prio 2 protocol 0xdead \\
 103         u32 match u32 0 0 flowid 1:1 \\
 104         action ife decode reclassify
 105 # tc filter add dev eth0 parent ffff: prio 3 protocol ip \\
 106         u32 match ip protocol 0xff flowid 1:1 \\
 107         action continue
 108 .EE
 109 .RE
 110
 111 Match with skb mark of 17:
 112
 113 .RS
 114 .EX
 115 # tc filter add dev eth0 parent ffff: prio 4 protocol ip \\
 116         handle 0x11 fw flowid 1:1 \\
 117         action ok
 118 .EE
 119 .RE
 120
 121 Configure the sending side to encode for the filters above. Use a destination
 122 IP address of 192.168.122.237/24, then tag with skb mark of decimal 17. Encode
 123 the packaet with ethertype 0xdead, add skb->mark to whitelist of metadatum to
 124 send, and rewrite the destination MAC address to 02:15:15:15:15:15.
 125
 126 .RS
 127 .EX
 128 # tc qdisc add dev eth0 root handle 1: prio
 129 # tc filter add dev eth0 parent 1: protocol ip prio 10 u32 \\
 130         match ip dst 192.168.122.237/24 \\
 131         match ip protocol 1 0xff \\
 132         flowid 1:2 \\
 133         action skbedit mark 17 \\
 134         action ife encode \\
 135         type 0xDEAD \\
 136         allow mark \\
 137         dst 02:15:15:15:15:15
 138 .EE
 139 .RE
 140
 141 .SH SEE ALSO
 142 .BR tc (8),
 143 .BR tc-u32 (8)