diff options
Diffstat (limited to 'lib/diameter/src/base/diameter_codec.erl')
| -rw-r--r-- | lib/diameter/src/base/diameter_codec.erl | 224 |
1 files changed, 129 insertions, 95 deletions
diff --git a/lib/diameter/src/base/diameter_codec.erl b/lib/diameter/src/base/diameter_codec.erl index 0de4d53973..a2b04bfd63 100644 --- a/lib/diameter/src/base/diameter_codec.erl +++ b/lib/diameter/src/base/diameter_codec.erl @@ -1,7 +1,7 @@ %% %% %CopyrightBegin% %% -%% Copyright Ericsson AB 2010-2013. All Rights Reserved. +%% Copyright Ericsson AB 2010-2014. All Rights Reserved. %% %% The contents of this file are subject to the Erlang Public License, %% Version 1.1, (the "License"); you may not use this file except in @@ -70,12 +70,15 @@ encode(Mod, #diameter_packet{} = Pkt) -> try e(Mod, Pkt) catch + exit: {Reason, Stack, #diameter_header{} = H} = T -> + %% Exit with a header in the reason to let the caller + %% count encode errors. + ?LOG(encode_error, {Reason, Stack, H}), + exit({?MODULE, encode, T}); error: Reason -> - %% Be verbose since a crash report may be truncated and - %% encode errors are self-inflicted. - X = {?MODULE, encode, {Reason, ?STACK}}, - diameter_lib:error_report(X, {?MODULE, encode, [Mod, Pkt]}), - exit(X) + T = {Reason, diameter_lib:get_stacktrace()}, + ?LOG(encode_error, T), + exit({?MODULE, encode, T}) end; encode(Mod, Msg) -> @@ -87,53 +90,62 @@ encode(Mod, Msg) -> msg = Msg}). e(_, #diameter_packet{msg = [#diameter_header{} = Hdr | As]} = Pkt) -> - Avps = encode_avps(As), - Length = size(Avps) + 20, - - #diameter_header{version = Vsn, - cmd_code = Code, - application_id = Aid, - hop_by_hop_id = Hid, - end_to_end_id = Eid} - = Hdr, - - Flags = make_flags(0, Hdr), - - Pkt#diameter_packet{header = Hdr, - bin = <<Vsn:8, Length:24, - Flags:8, Code:24, - Aid:32, - Hid:32, - Eid:32, - Avps/binary>>}; + try encode_avps(As) of + Avps -> + Length = size(Avps) + 20, + + #diameter_header{version = Vsn, + cmd_code = Code, + application_id = Aid, + hop_by_hop_id = Hid, + end_to_end_id = Eid} + = Hdr, + + Flags = make_flags(0, Hdr), + + Pkt#diameter_packet{header = Hdr, + bin = <<Vsn:8, Length:24, + Flags:8, Code:24, + Aid:32, + Hid:32, + Eid:32, + Avps/binary>>} + catch + error: Reason -> + exit({Reason, diameter_lib:get_stacktrace(), Hdr}) + end; -e(Mod, #diameter_packet{header = Hdr, msg = Msg} = Pkt) -> +e(Mod, #diameter_packet{header = Hdr0, msg = Msg} = Pkt) -> #diameter_header{version = Vsn, hop_by_hop_id = Hid, end_to_end_id = Eid} - = Hdr, + = Hdr0, MsgName = rec2msg(Mod, Msg), - {Code, Flags0, Aid} = msg_header(Mod, MsgName, Hdr), - Flags = make_flags(Flags0, Hdr), - - Avps = encode_avps(Mod, MsgName, values(Msg)), - Length = size(Avps) + 20, - - Pkt#diameter_packet{header = Hdr#diameter_header - {length = Length, - cmd_code = Code, - application_id = Aid, - is_request = 0 /= ?MASK(7, Flags), - is_proxiable = 0 /= ?MASK(6, Flags), - is_error = 0 /= ?MASK(5, Flags), - is_retransmitted = 0 /= ?MASK(4, Flags)}, - bin = <<Vsn:8, Length:24, - Flags:8, Code:24, - Aid:32, - Hid:32, - Eid:32, - Avps/binary>>}. + {Code, Flags0, Aid} = msg_header(Mod, MsgName, Hdr0), + Flags = make_flags(Flags0, Hdr0), + Hdr = Hdr0#diameter_header{cmd_code = Code, + application_id = Aid, + is_request = 0 /= ?MASK(7, Flags), + is_proxiable = 0 /= ?MASK(6, Flags), + is_error = 0 /= ?MASK(5, Flags), + is_retransmitted = 0 /= ?MASK(4, Flags)}, + Values = values(Msg), + + try encode_avps(Mod, MsgName, Values) of + Avps -> + Length = size(Avps) + 20, + Pkt#diameter_packet{header = Hdr#diameter_header{length = Length}, + bin = <<Vsn:8, Length:24, + Flags:8, Code:24, + Aid:32, + Hid:32, + Eid:32, + Avps/binary>>} + catch + error: Reason -> + exit({Reason, diameter_lib:get_stacktrace(), Hdr}) + end. %% make_flags/2 @@ -225,15 +237,35 @@ rec2msg(Mod, Rec) -> %% Unsuccessfully decoded AVPs will be placed in #diameter_packet.errors. --spec decode(module(), #diameter_packet{} | bitstring()) +-spec decode(module() | {module(), module()}, #diameter_packet{} | binary()) -> #diameter_packet{}. +%% An Answer setting the E-bit. The application dictionary is needed +%% for the best-effort decode of Failed-AVP, and the best way to make +%% this available to the AVP decode in diameter_gen.hrl, without +%% having to rewrite the entire codec generation, is to place it in +%% the process dictionary. It's the code in diameter_gen.hrl (that's +%% included by every generated codec module) that looks for the entry. +%% Not ideal, but it solves the problem relatively simply. +decode({Mod, Mod}, Pkt) -> + decode(Mod, Pkt); +decode({Mod, AppMod}, Pkt) -> + Key = {?MODULE, dictionary}, + put(Key, AppMod), + try + decode(Mod, Pkt) + after + erase(Key) + end; + +%% Or not: a request, or an answer not setting the E-bit. decode(Mod, Pkt) -> decode(Mod:id(), Mod, Pkt). -%% If we're a relay application then just extract the avp's without -%% any decoding of their data since we don't know the application in -%% question. +%% decode/3 + +%% Relay application: just extract the avp's without any decoding of +%% their data since we don't know the application in question. decode(?APP_ID_RELAY, _, #diameter_packet{} = Pkt) -> case collect_avps(Pkt) of {E, As} -> @@ -259,34 +291,36 @@ 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/4 + decode_avps(MsgName, Mod, Pkt, {E, Avps}) -> - ?LOG(invalid, Pkt#diameter_packet.bin), + ?LOG(invalid_avp_length, Pkt#diameter_packet.header), #diameter_packet{errors = Failed} = P = decode_avps(MsgName, Mod, Pkt, Avps), P#diameter_packet{errors = [E | Failed]}; -decode_avps('', Mod, Pkt, Avps) -> %% unknown message ... - ?LOG(unknown, {Mod, Pkt#diameter_packet.header}), +decode_avps('', _, Pkt, Avps) -> %% unknown message ... + ?LOG(unknown_message, Pkt#diameter_packet.header), Pkt#diameter_packet{avps = lists:reverse(Avps), errors = [3001]}; %% DIAMETER_COMMAND_UNSUPPORTED %% msg = undefined identifies this case. decode_avps(MsgName, Mod, Pkt, Avps) -> %% ... or not - {Rec, As, Failed} = Mod:decode_avps(MsgName, Avps), - ?LOGC([] /= Failed, failed, {Mod, Failed}), + {Rec, As, Errors} = Mod:decode_avps(MsgName, Avps), + ?LOGC([] /= Errors, decode_errors, Pkt#diameter_packet.header), Pkt#diameter_packet{msg = Rec, - errors = Failed, + errors = Errors, avps = As}. %%% --------------------------------------------------------------------------- %%% # decode_header/1 %%% --------------------------------------------------------------------------- --spec decode_header(bitstring()) +-spec decode_header(binary()) -> #diameter_header{} | false. @@ -297,7 +331,7 @@ 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 @@ -410,7 +444,7 @@ 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}. %%% --------------------------------------------------------------------------- @@ -421,17 +455,18 @@ 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) -> @@ -461,7 +496,9 @@ 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, @@ -471,17 +508,15 @@ 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: %% @@ -516,34 +551,27 @@ 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 %%% --------------------------------------------------------------------------- @@ -575,17 +603,23 @@ 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 in diameter_gen ... +%% ... when ignoring errors in Failed-AVP ... +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, |