Merge pull request msantos#37 from shun159/feature/mpls

Add MPLS codec
sebastiw · Jul 15, 2016 · c19e086 · c19e086
2 parents 1ed6013 + 30a99ed
commit c19e086
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Showing 7 changed files with 188 additions and 1 deletion.
diff --git a/include/pkt.hrl b/include/pkt.hrl
@@ -7,6 +7,7 @@
 -include("pkt_802_1q.hrl").
 -include("pkt_arp.hrl").
 -include("pkt_lldp.hrl").
+-include("pkt_mpls.hrl").
 
 -include("pkt_gre.hrl").
 -include("pkt_icmp6.hrl").

diff --git a/include/pkt_ether.hrl b/include/pkt_ether.hrl
@@ -5,6 +5,8 @@
 -define(ETH_P_802_1Q, 16#8100).
 -define(ETH_P_802_1QinQ, 16#88a8).
 -define(ETH_P_LLDP, 16#88CC).
+-define(ETH_P_MPLS_UNI, 16#8847).
+-define(ETH_P_MPLS_MULTI, 16#8848).
 
 -record(ether, {
     dhost = <<0,0,0,0,0,0>> :: <<_:48>>,

diff --git a/include/pkt_mpls.hrl b/include/pkt_mpls.hrl
@@ -0,0 +1,32 @@
+-define(MPLS_LABEL_IPV4NULL, 0).
+-define(MPLS_LABEL_RTALERT, 1).
+-define(MPLS_LABEL_IPV6NULL, 2).
+-define(MPLS_LABEL_IMPLNULL, 3).
+-define(MPLS_LABEL_ENTROPY, 7).
+-define(MPLS_LABEL_GAL, 13).
+-define(MPLS_LABEL_OAMALERT, 14).
+-define(MPLS_LABEL_EXTENSION, 15).
+-define(MPLS_LABEL_FIRST_UNRESERVED, 16).
+
+%% Reference: RFC 5462, RFC 3032
+%%
+%%   0                   1                   2                   3
+%%   0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+%%  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+%%  |                Label                  | TC  |S|       TTL     |
+%%  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+%%
+%% 	Label:  Label Value, 20 bits
+%% 	TC:     Traffic Class field, 3 bits
+%% 	S:      Bottom of Stack, 1 bit
+%% 	TTL:    Time to Live, 8 bits
+%%
+
+-record(shim, {label = 0 :: 1..16#fffff,
+               tc = 0 :: 1..7,
+               s = true :: boolean(),
+               ttl = 0 :: pkt:uint8_t()}).
+-type shim() :: #shim{}.
+
+-record(mpls, {labels = [] :: [shim()]}).
+-type mpls() :: #mpls{}.
diff --git a/src/pkt.erl b/src/pkt.erl
@@ -40,6 +40,7 @@
         makesum/1,
         ether/1,
         ether_type/1,
+        mpls/1,
         '802.1q'/1,
         llc/1,
         arp/1,
@@ -117,6 +118,9 @@ decapsulate_next({linux_cooked, Data}, Headers) ->
 decapsulate_next({ether, Data}, Headers) ->
     {Header, Payload} = ether(Data),
     decapsulate_next({next(Header), Payload}, [Header|Headers]);
+decapsulate_next({mpls, Data}, Headers) ->
+    {Header, Next, Payload} = mpls(Data),
+    decapsulate_next({Next, Payload}, [Header|Headers]);
 decapsulate_next({'802.1q', Data}, Headers) ->
     {Header, Payload} = '802.1q'(Data),
     decapsulate_next({next(Header), Payload}, [Header|Headers]);
@@ -296,6 +300,10 @@ ether(N) ->
 ether_type(N) ->
     pkt_ether:type(N).
 
+%% MPLS
+mpls(N) ->
+    pkt_mpls:codec(N).
+
 %% ARP
 arp(N) ->
     pkt_arp:codec(N).

diff --git a/src/pkt_ether.erl b/src/pkt_ether.erl
@@ -43,7 +43,10 @@ type(EtherType) when EtherType < 16#05DC -> llc;
 %% 802.1Q Virtual LAN
 type(?ETH_P_802_1Q) -> '802.1q';
 %% 802.1ad (802.1q QinQ)
-type(?ETH_P_802_1QinQ) -> '802.1qinq'.
+type(?ETH_P_802_1QinQ) -> '802.1qinq';
+%% MPLS_
+type(?ETH_P_MPLS_UNI) -> mpls;
+type(?ETH_P_MPLS_MULTI) -> mpls.
 
 codec(<<Dhost:6/bytes, Shost:6/bytes, Type:16, Payload/binary>>) ->
 %    Len = byte_size(Packet) - 4,

diff --git a/src/pkt_mpls.erl b/src/pkt_mpls.erl
@@ -0,0 +1,29 @@
+-module(pkt_mpls).
+
+-include("pkt_mpls.hrl").
+
+-export([codec/1]).
+
+codec(Mpls) when is_binary(Mpls) ->
+    decode(Mpls, []);
+codec(#mpls{labels = Labels}) ->
+    encode(Labels, <<>>).
+
+decode(<<L:20, Tc:3, 1:1, Ttl:8, Rest/binary>>, Labels0) ->
+    Mpls = #shim{label = L, tc = Tc, s = true, ttl = Ttl},
+    Labels = #mpls{labels = lists:reverse([Mpls|Labels0])},
+    {Next, Payload} = next_header(Rest),
+    {Labels, Next, Payload};
+decode(<<L:20, Tc:3, 0:1, Ttl:8, Rest/binary>>, Labels0) ->
+    Mpls = #shim{label = L, tc = Tc, s = false, ttl = Ttl},
+    decode(Rest, [Mpls|Labels0]).
+
+encode([], Bin) -> Bin;
+encode([#shim{label = L, tc = Tc, s = true, ttl = Ttl}|_], Bin) ->
+    <<Bin/bytes, L:20, Tc:3, 1:1, Ttl:8>>;
+encode([#shim{label = L, tc = Tc, s = false, ttl = Ttl}|Rest], Bin) ->
+    encode(Rest, <<L:20, Tc:3, 0:1, Ttl:8, Bin/bytes>>).
+
+next_header(<<>>) -> {none, <<>>};
+next_header(<<4:4, _/bitstring>> = Binary) -> {ipv4, Binary};
+next_header(<<6:4, _/bitstring>> = Binary) -> {ipv6, Binary}.
diff --git a/test/pkt_mpls_tests.erl b/test/pkt_mpls_tests.erl
@@ -0,0 +1,112 @@
+-module(pkt_mpls_tests).
+
+-include_lib("pkt/include/pkt.hrl").
+-include_lib("eunit/include/eunit.hrl").
+
+codec_test_() ->
+    [decode_single_tagging(),
+     decode_double_tagging()].
+
+decode_single_tagging() ->
+    Frame = pkt:decapsulate(single()),
+    [#ether{dhost = <<194,5,99,77,0,0>>,
+            shost = <<194,3,99,62,0,0>>,
+            type = 34887,crc = 0},
+     #mpls{labels = [#shim{label = 18,
+                           tc = 0,
+                           s = true,
+                           ttl = 254}]},
+     #ipv4{v = 4,
+           hl = 5,
+           tos = 0,
+           len = 100,
+           id = 25,
+           df = 0,mf = 0,
+           off = 0,
+           ttl = 254,
+           p = 1,
+           sum = 2349,
+           saddr = {192,168,10,1},
+           daddr = {192,168,40,1},
+           opt = <<>>},
+     #icmp{type = 8,
+           code = 0,checksum = 28057,id = 5,
+           sequence = 0,
+           gateway = {127,0,0,1},
+           un = <<0,0,0,0>>,
+           mtu = 0,
+           pointer = 0,
+           ts_orig = 0,
+           ts_recv = 0,
+           ts_tx = 0},
+     _] = Frame.
+
+decode_double_tagging() ->
+    Frame = pkt:decapsulate(double()),
+    [#ether{dhost = <<0,48,150,230,252,57>>,
+            shost = <<0,48,150,5,40,56>>,
+            type = 34887,crc = 0},
+     #mpls{labels = [#shim{label = 18,tc = 0,s = false,ttl = 255},
+                     #shim{label = 16,tc = 0,s = true,ttl = 255}]},
+     #ipv4{v = 4,
+           hl = 5,
+           tos = 0,
+           len = 100,
+           id = 80,
+           df = 0,
+           mf = 0,
+           off = 0,
+           ttl = 255,
+           p = 1,
+           sum = 42758,
+           saddr = {10,31,0,1},
+           daddr = {10,34,0,1},
+           opt = <<>>},
+     #icmp{type = 8,
+           code = 0,
+           checksum = 48401,
+           id = 3941,
+           sequence = 4768,
+           gateway = {127,0,0,1},
+           un = <<0,0,0,0>>,
+           mtu = 0,
+           pointer = 0,
+           ts_orig = 0,
+           ts_recv = 0,
+           ts_tx = 0},
+     _] = Frame.
+
+single() ->
+    <<16#c2, 16#05, 16#63, 16#4d, 16#00, 16#00, 16#c2, 16#03,
+      16#63, 16#3e, 16#00, 16#00, 16#88, 16#47, 16#00, 16#01,
+      16#21, 16#fe, 16#45, 16#00, 16#00, 16#64, 16#00, 16#19,
+      16#00, 16#00, 16#fe, 16#01, 16#09, 16#2d, 16#c0, 16#a8,
+      16#0a, 16#01, 16#c0, 16#a8, 16#28, 16#01, 16#08, 16#00,
+      16#6d, 16#99, 16#00, 16#05, 16#00, 16#00, 16#00, 16#00,
+      16#00, 16#00, 16#00, 16#24, 16#10, 16#88, 16#ab, 16#cd,
+      16#ab, 16#cd, 16#ab, 16#cd, 16#ab, 16#cd, 16#ab, 16#cd,
+      16#ab, 16#cd, 16#ab, 16#cd, 16#ab, 16#cd, 16#ab, 16#cd,
+      16#ab, 16#cd, 16#ab, 16#cd, 16#ab, 16#cd, 16#ab, 16#cd,
+      16#ab, 16#cd, 16#ab, 16#cd, 16#ab, 16#cd, 16#ab, 16#cd,
+      16#ab, 16#cd, 16#ab, 16#cd, 16#ab, 16#cd, 16#ab, 16#cd,
+      16#ab, 16#cd, 16#ab, 16#cd, 16#ab, 16#cd, 16#ab, 16#cd,
+      16#ab, 16#cd, 16#ab, 16#cd, 16#ab, 16#cd, 16#ab, 16#cd,
+      16#ab, 16#cd, 16#ab, 16#cd, 16#ab, 16#cd>>.
+
+double() ->
+    <<16#00, 16#30, 16#96, 16#e6, 16#fc, 16#39, 16#00, 16#30,
+      16#96, 16#05, 16#28, 16#38, 16#88, 16#47, 16#00, 16#01,
+      16#20, 16#ff, 16#00, 16#01, 16#01, 16#ff, 16#45, 16#00,
+      16#00, 16#64, 16#00, 16#50, 16#00, 16#00, 16#ff, 16#01,
+      16#a7, 16#06, 16#0a, 16#1f, 16#00, 16#01, 16#0a, 16#22,
+      16#00, 16#01, 16#08, 16#00, 16#bd, 16#11, 16#0f, 16#65,
+      16#12, 16#a0, 16#00, 16#00, 16#00, 16#00, 16#00, 16#53,
+      16#9e, 16#e0, 16#ab, 16#cd, 16#ab, 16#cd, 16#ab, 16#cd,
+      16#ab, 16#cd, 16#ab, 16#cd, 16#ab, 16#cd, 16#ab, 16#cd,
+      16#ab, 16#cd, 16#ab, 16#cd, 16#ab, 16#cd, 16#ab, 16#cd,
+      16#ab, 16#cd, 16#ab, 16#cd, 16#ab, 16#cd, 16#ab, 16#cd,
+      16#ab, 16#cd, 16#ab, 16#cd, 16#ab, 16#cd, 16#ab, 16#cd,
+      16#ab, 16#cd, 16#ab, 16#cd, 16#ab, 16#cd, 16#ab, 16#cd,
+      16#ab, 16#cd, 16#ab, 16#cd, 16#ab, 16#cd, 16#ab, 16#cd,
+      16#ab, 16#cd, 16#ab, 16#cd, 16#ab, 16#cd, 16#ab, 16#cd,
+      16#ab, 16#cd>>.