diff options
Diffstat (limited to 'lib/diameter/src/base/diameter_codec.erl')
-rw-r--r-- | lib/diameter/src/base/diameter_codec.erl | 77 |
1 files changed, 38 insertions, 39 deletions
diff --git a/lib/diameter/src/base/diameter_codec.erl b/lib/diameter/src/base/diameter_codec.erl index 84139d7f5e..0ca4a84d21 100644 --- a/lib/diameter/src/base/diameter_codec.erl +++ b/lib/diameter/src/base/diameter_codec.erl @@ -237,7 +237,7 @@ rec2msg(Mod, Rec) -> %% Unsuccessfully decoded AVPs will be placed in #diameter_packet.errors. --spec decode(module(), #diameter_packet{} | bitstring()) +-spec decode(module(), #diameter_packet{} | binary()) -> #diameter_packet{}. decode(Mod, Pkt) -> @@ -271,7 +271,7 @@ decode(_, Mod, #diameter_packet{header = Hdr} = Pkt) -> decode_avps(MsgName, Mod, Pkt, collect_avps(Pkt)); decode(Id, Mod, Bin) - when is_bitstring(Bin) -> + when is_binary(Bin) -> decode(Id, Mod, #diameter_packet{header = decode_header(Bin), bin = Bin}). decode_avps(MsgName, Mod, Pkt, {E, Avps}) -> @@ -298,7 +298,7 @@ decode_avps(MsgName, Mod, Pkt, Avps) -> %% ... or not %%% # decode_header/1 %%% --------------------------------------------------------------------------- --spec decode_header(bitstring()) +-spec decode_header(binary()) -> #diameter_header{} | false. @@ -309,7 +309,7 @@ decode_header(<<Version:8, ApplicationId:32, HopByHopId:32, EndToEndId:32, - _/bitstring>>) -> + _/binary>>) -> <<R:1, P:1, E:1, T:1, _:4>> = CmdFlags, %% 3588 (ch 3) says that reserved bits MUST be set to 0 and ignored @@ -422,7 +422,7 @@ msg_id(#diameter_header{application_id = A, is_request = R}) -> {A, C, if R -> 1; true -> 0 end}; -msg_id(<<_:32, Rbit:1, _:7, CmdCode:24, ApplId:32, _/bitstring>>) -> +msg_id(<<_:32, Rbit:1, _:7, CmdCode:24, ApplId:32, _/binary>>) -> {ApplId, CmdCode, Rbit}. %%% --------------------------------------------------------------------------- @@ -433,17 +433,18 @@ msg_id(<<_:32, Rbit:1, _:7, CmdCode:24, ApplId:32, _/bitstring>>) -> %% order in the binary. Note also that grouped avp's aren't unraveled, %% only those at the top level. --spec collect_avps(#diameter_packet{} | bitstring()) +-spec collect_avps(#diameter_packet{} | binary()) -> [Avp] | {Error, [Avp]} when Avp :: #diameter_avp{}, Error :: {5014, #diameter_avp{}}. collect_avps(#diameter_packet{bin = Bin}) -> - <<_:20/binary, Avps/bitstring>> = Bin, + <<_:20/binary, Avps/binary>> = Bin, collect_avps(Avps); -collect_avps(Bin) -> +collect_avps(Bin) + when is_binary(Bin) -> collect_avps(Bin, 0, []). collect_avps(<<>>, _, Acc) -> @@ -473,7 +474,9 @@ collect_avps(Bin, N, Acc) -> split_avp(Bin) -> {Code, V, M, P, Len, HdrLen} = split_head(Bin), - {Data, B} = split_data(Bin, HdrLen, Len - HdrLen), + + <<_:HdrLen/binary, Rest/binary>> = Bin, + {Data, B} = split_data(Rest, Len - HdrLen), {B, #diameter_avp{code = Code, vendor_id = V, @@ -483,17 +486,15 @@ split_avp(Bin) -> %% split_head/1 -split_head(<<Code:32, 1:1, M:1, P:1, _:5, Len:24, V:32, _/bitstring>>) -> +split_head(<<Code:32, 1:1, M:1, P:1, _:5, Len:24, V:32, _/binary>>) -> {Code, V, M, P, Len, 12}; -split_head(<<Code:32, 0:1, M:1, P:1, _:5, Len:24, _/bitstring>>) -> +split_head(<<Code:32, 0:1, M:1, P:1, _:5, Len:24, _/binary>>) -> {Code, undefined, M, P, Len, 8}; -%% Header is truncated: pack_avp/1 will pad to the minimum header -%% length. -split_head(B) - when is_bitstring(B) -> - ?THROW({5014, #diameter_avp{data = B}}). +%% Header is truncated. +split_head(Bin) -> + ?THROW({5014, #diameter_avp{data = Bin}}). %% 3588: %% @@ -528,34 +529,27 @@ split_head(B) %% split_data/3 -split_data(Bin, HdrLen, Len) - when 0 =< Len -> - split_data(Bin, HdrLen, Len, (4 - (Len rem 4)) rem 4); - -split_data(_, _, _) -> - invalid_avp_length(). +split_data(Bin, Len) -> + Pad = (4 - (Len rem 4)) rem 4, -%% split_data/4 + %% Len might be negative here, but that ensures the failure of the + %% binary match. -split_data(Bin, HdrLen, Len, Pad) -> case Bin of - <<_:HdrLen/binary, Data:Len/binary, _:Pad/binary, Rest/bitstring>> -> + <<Data:Len/binary, _:Pad/binary, Rest/binary>> -> {Data, Rest}; _ -> - invalid_avp_length() + %% Header length points past the end of the message. As + %% stated in the 6733 text above, it's sufficient to + %% return a zero-filled minimal payload if this is a + %% request. Do this (in cases that we know the type) by + %% inducing a decode failure and letting the dictionary's + %% decode (in diameter_gen) deal with it. Here we don't + %% know type. If the type isn't known, then the decode + %% just strips the extra bit. + {<<0:1, Bin/binary>>, <<>>} end. -%% invalid_avp_length/0 -%% -%% AVP Length doesn't mesh with payload. Induce a decode error by -%% returning a payload that no valid Diameter type can have. This is -%% so that a known AVP will result in 5014 error with a zero'd -%% payload. Here we simply don't know how to construct this payload. -%% (Yes, this solution is an afterthought.) - -invalid_avp_length() -> - {<<0:1>>, <<>>}. - %%% --------------------------------------------------------------------------- %%% # pack_avp/1 %%% --------------------------------------------------------------------------- @@ -587,17 +581,22 @@ pack_avp(#diameter_avp{data = {Dict, Name, Value}} = A) -> {Name, Type} = Dict:avp_name(Code, Vid), pack_avp(A#diameter_avp{data = {Hdr, {Type, Value}}}); +%% ... with a truncated header ... pack_avp(#diameter_avp{code = undefined, data = B}) - when is_bitstring(B) -> + when is_binary(B) -> %% Reset the AVP Length of an AVP Header resulting from a 5014 %% error. The RFC doesn't explicitly say to do this but the %% receiver can't correctly extract this and following AVP's %% without a correct length. On the downside, the header doesn't %% reveal if the received header has been padded. Pad = 8*header_length(B) - bit_size(B), - Len = size(<<H:5/binary, _:24, T/binary>> = <<B/bitstring, 0:Pad>>), + Len = size(<<H:5/binary, _:24, T/binary>> = <<B/binary, 0:Pad>>), <<H/binary, Len:24, T/binary>>; +%% ... from a dictionary compiled against old code (diameter_gen) ... +pack_avp(#diameter_avp{data = <<0:1, B/binary>>} = A) -> + pack_avp(A#diameter_avp{data = B}); + %% ... or as an iolist. pack_avp(#diameter_avp{code = Code, vendor_id = V, |