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-rw-r--r--lib/asn1/src/asn1rt_uper_bin.erl1635
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diff --git a/lib/asn1/src/asn1rt_uper_bin.erl b/lib/asn1/src/asn1rt_uper_bin.erl
new file mode 100644
index 0000000000..a964b835ae
--- /dev/null
+++ b/lib/asn1/src/asn1rt_uper_bin.erl
@@ -0,0 +1,1635 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2008-2009. 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
+%% compliance with the License. You should have received a copy of the
+%% Erlang Public License along with this software. If not, it can be
+%% retrieved online at http://www.erlang.org/.
+%%
+%% Software distributed under the License is distributed on an "AS IS"
+%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+%% the License for the specific language governing rights and limitations
+%% under the License.
+%%
+%% %CopyrightEnd%
+%%
+%%
+-module(asn1rt_uper_bin).
+
+%% encoding / decoding of PER unaligned
+
+-include("asn1_records.hrl").
+
+%%-compile(export_all).
+
+ -export([cindex/3, list_to_record/2]).
+ -export([setext/1, fixoptionals/3,
+ fixextensions/2,
+ getext/1, getextension/2, skipextensions/3, getbit/1, getchoice/3 ]).
+ -export([getoptionals2/2, set_choice/3, encode_integer/2, encode_integer/3 ]).
+ -export([decode_integer/2, decode_integer/3, encode_small_number/1, encode_boolean/1,
+ decode_boolean/1, encode_length/2, decode_length/1, decode_length/2,
+ encode_small_length/1, decode_small_length/1,
+ decode_compact_bit_string/3]).
+ -export([decode_enumerated/3,
+ encode_bit_string/3, decode_bit_string/3 ]).
+ -export([encode_octet_string/2, decode_octet_string/2,
+ encode_null/1, decode_null/1,
+ encode_relative_oid/1, decode_relative_oid/1,
+ encode_object_identifier/1, decode_object_identifier/1,
+ encode_real/1, decode_real/1,
+ complete/1, complete_NFP/1]).
+
+
+ -export([encode_open_type/2, decode_open_type/2]).
+
+ -export([encode_UniversalString/2, decode_UniversalString/2,
+ encode_PrintableString/2, decode_PrintableString/2,
+ encode_GeneralString/2, decode_GeneralString/2,
+ encode_GraphicString/2, decode_GraphicString/2,
+ encode_TeletexString/2, decode_TeletexString/2,
+ encode_VideotexString/2, decode_VideotexString/2,
+ encode_VisibleString/2, decode_VisibleString/2,
+ encode_UTF8String/1, decode_UTF8String/1,
+ encode_BMPString/2, decode_BMPString/2,
+ encode_IA5String/2, decode_IA5String/2,
+ encode_NumericString/2, decode_NumericString/2,
+ encode_ObjectDescriptor/2, decode_ObjectDescriptor/1
+ ]).
+
+-define('16K',16384).
+-define('32K',32768).
+-define('64K',65536).
+
+
+cindex(Ix,Val,Cname) ->
+ case element(Ix,Val) of
+ {Cname,Val2} -> Val2;
+ X -> X
+ end.
+
+%% converts a list to a record if necessary
+list_to_record(_Name,Tuple) when is_tuple(Tuple) ->
+ Tuple;
+list_to_record(Name,List) when is_list(List) ->
+ list_to_tuple([Name|List]).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% setext(true|false) -> CompleteList
+%%
+
+setext(false) ->
+ <<0:1>>;
+setext(true) ->
+ <<1:1>>.
+
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% This is the new fixoptionals/3 which is used by the new generates
+%%
+fixoptionals(OptList,OptLength,Val) when is_tuple(Val) ->
+ Bits = fixoptionals(OptList,Val,0),
+ {Val,<<Bits:OptLength>>};
+
+fixoptionals([],_Val,Acc) ->
+ %% Optbits
+ Acc;
+fixoptionals([{Pos,DefVal}|Ot],Val,Acc) ->
+ case element(Pos,Val) of
+ asn1_DEFAULT -> fixoptionals(Ot,Val,Acc bsl 1);
+ DefVal -> fixoptionals(Ot,Val,Acc bsl 1);
+ _ -> fixoptionals(Ot,Val,(Acc bsl 1) + 1)
+ end;
+fixoptionals([Pos|Ot],Val,Acc) ->
+ case element(Pos,Val) of
+ asn1_NOVALUE -> fixoptionals(Ot,Val,Acc bsl 1);
+ asn1_DEFAULT -> fixoptionals(Ot,Val,Acc bsl 1);
+ _ -> fixoptionals(Ot,Val,(Acc bsl 1) + 1)
+ end.
+
+
+getext(Bytes) when is_bitstring(Bytes) ->
+ getbit(Bytes).
+
+getextension(0, Bytes) ->
+ {{},Bytes};
+getextension(1, Bytes) ->
+ {Len,Bytes2} = decode_small_length(Bytes),
+ {Blist, Bytes3} = getbits_as_list(Len,Bytes2),
+ {list_to_tuple(Blist),Bytes3}.
+
+fixextensions({ext,ExtPos,ExtNum},Val) ->
+ case fixextensions(ExtPos,ExtNum+ExtPos,Val,0) of
+ 0 -> [];
+ ExtBits ->
+ [encode_small_length(ExtNum),<<ExtBits:ExtNum>>]
+ end.
+
+fixextensions(Pos,MaxPos,_,Acc) when Pos >= MaxPos ->
+ Acc;
+fixextensions(Pos,ExtPos,Val,Acc) ->
+ Bit = case catch(element(Pos+1,Val)) of
+ asn1_NOVALUE ->
+ 0;
+ asn1_NOEXTVALUE ->
+ 0;
+ {'EXIT',_} ->
+ 0;
+ _ ->
+ 1
+ end,
+ fixextensions(Pos+1,ExtPos,Val,(Acc bsl 1)+Bit).
+
+skipextensions(Bytes,Nr,ExtensionBitPattern) ->
+ case (catch element(Nr,ExtensionBitPattern)) of
+ 1 ->
+ {_,Bytes2} = decode_open_type(Bytes,[]),
+ skipextensions(Bytes2, Nr+1, ExtensionBitPattern);
+ 0 ->
+ skipextensions(Bytes, Nr+1, ExtensionBitPattern);
+ {'EXIT',_} -> % badarg, no more extensions
+ Bytes
+ end.
+
+
+getchoice(Bytes,1,0) -> % only 1 alternative is not encoded
+ {0,Bytes};
+getchoice(Bytes,_,1) ->
+ decode_small_number(Bytes);
+getchoice(Bytes,NumChoices,0) ->
+ decode_constrained_number(Bytes,{0,NumChoices-1}).
+
+
+%%%%%%%%%%%%%%%
+getoptionals2(Bytes,NumOpt) ->
+ getbits(Bytes,NumOpt).
+
+
+%% getbits_as_binary(Num,Bytes) -> {{Unused,BinBits},RestBytes},
+%% Num = integer(),
+%% Bytes = list() | tuple(),
+%% Unused = integer(),
+%% BinBits = binary(),
+%% RestBytes = tuple()
+getbits_as_binary(Num,Bytes) when is_bitstring(Bytes) ->
+ <<BS:Num/bitstring,Rest/bitstring>> = Bytes,
+ {BS,Rest}.
+
+getbits_as_list(Num,Bytes) when is_bitstring(Bytes) ->
+ <<BitStr:Num/bitstring,Rest/bitstring>> = Bytes,
+ {[ B || <<B:1>> <= BitStr],Rest}.
+
+getbit(Buffer) ->
+ <<B:1,Rest/bitstring>> = Buffer,
+ {B,Rest}.
+
+
+getbits(Buffer,Num) when is_bitstring(Buffer) ->
+ <<Bs:Num,Rest/bitstring>> = Buffer,
+ {Bs,Rest}.
+
+
+
+%% Pick the first Num octets.
+%% Returns octets as an integer with bit significance as in buffer.
+getoctets(Buffer,Num) when is_bitstring(Buffer) ->
+ <<Val:Num/integer-unit:8,RestBitStr/bitstring>> = Buffer,
+ {Val,RestBitStr}.
+
+%% Pick the first Num octets.
+%% Returns octets as a binary
+getoctets_as_bin(Bin,Num) when is_bitstring(Bin) ->
+ <<Octets:Num/binary,RestBin/bitstring>> = Bin,
+ {Octets,RestBin}.
+
+%% same as above but returns octets as a List
+getoctets_as_list(Buffer,Num) ->
+ {Bin,Buffer2} = getoctets_as_bin(Buffer,Num),
+ {binary_to_list(Bin),Buffer2}.
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% set_choice(Alt,Choices,Altnum) -> ListofBitSettings
+%% Alt = atom()
+%% Altnum = integer() | {integer(),integer()}% number of alternatives
+%% Choices = [atom()] | {[atom()],[atom()]}
+%% When Choices is a tuple the first list is the Rootset and the
+%% second is the Extensions and then Altnum must also be a tuple with the
+%% lengths of the 2 lists
+%%
+set_choice(Alt,{L1,L2},{Len1,_Len2}) ->
+ case set_choice_tag(Alt,L1) of
+ N when is_integer(N), Len1 > 1 ->
+ [<<0:1>>, % the value is in the root set
+ encode_integer([{'ValueRange',{0,Len1-1}}],N)];
+ N when is_integer(N) ->
+ <<0:1>>; % no encoding if only 0 or 1 alternative
+ false ->
+ [<<1:1>>, % extension value
+ case set_choice_tag(Alt,L2) of
+ N2 when is_integer(N2) ->
+ encode_small_number(N2);
+ false ->
+ unknown_choice_alt
+ end]
+ end;
+set_choice(Alt,L,Len) ->
+ case set_choice_tag(Alt,L) of
+ N when is_integer(N), Len > 1 ->
+ encode_integer([{'ValueRange',{0,Len-1}}],N);
+ N when is_integer(N) ->
+ []; % no encoding if only 0 or 1 alternative
+ false ->
+ [unknown_choice_alt]
+ end.
+
+set_choice_tag(Alt,Choices) ->
+ set_choice_tag(Alt,Choices,0).
+
+set_choice_tag(Alt,[Alt|_Rest],Tag) ->
+ Tag;
+set_choice_tag(Alt,[_H|Rest],Tag) ->
+ set_choice_tag(Alt,Rest,Tag+1);
+set_choice_tag(_Alt,[],_Tag) ->
+ false.
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% decode_fragmented_XXX; decode of values encoded fragmented according
+%% to ITU-T X.691 clause 10.9.3.8. The unit (XXX) is either bits, octets,
+%% characters or number of components (in a choice,sequence or similar).
+%% Buffer is a buffer {Used, Bin}.
+%% C is the constrained length.
+%% If the buffer is not aligned, this function does that.
+decode_fragmented_bits(Buffer,C) ->
+ decode_fragmented_bits(Buffer,C,[]).
+decode_fragmented_bits(<<3:2,Len:6,BitStr/bitstring>>,C,Acc) ->
+%% {Value,Bin2} = split_binary(Bin, Len * ?'16K'),
+ FragLen = (Len*?'16K') div 8,
+ <<Value:FragLen/binary,BitStr2/bitstring>> = BitStr,
+ decode_fragmented_bits(BitStr2,C,[Value|Acc]);
+decode_fragmented_bits(<<0:1,0:7,BitStr/bitstring>>,C,Acc) ->
+ BinBits = list_to_binary(lists:reverse(Acc)),
+ case C of
+ Int when is_integer(Int),C == size(BinBits) ->
+ {BinBits,BitStr};
+ Int when is_integer(Int) ->
+ exit({error,{asn1,{illegal_value,C,BinBits}}})
+ end;
+decode_fragmented_bits(<<0:1,Len:7,BitStr/bitstring>>,C,Acc) ->
+ <<Val:Len/bitstring,Rest/bitstring>> = BitStr,
+%% <<Value:Len/binary-unit:1,Bin2/binary>> = Bin,
+ ResBitStr = list_to_bitstring(lists:reverse([Val|Acc])),
+ case C of
+ Int when is_integer(Int),C == bit_size(ResBitStr) ->
+ {ResBitStr,Rest};
+ Int when is_integer(Int) ->
+ exit({error,{asn1,{illegal_value,C,ResBitStr}}})
+ end.
+
+
+decode_fragmented_octets({0,Bin},C) ->
+ decode_fragmented_octets(Bin,C,[]).
+
+decode_fragmented_octets(<<3:2,Len:6,BitStr/bitstring>>,C,Acc) ->
+ FragLen = Len * ?'16K',
+ <<Value:FragLen/binary,Rest/bitstring>> = BitStr,
+ decode_fragmented_octets(Rest,C,[Value|Acc]);
+decode_fragmented_octets(<<0:1,0:7,Bin/bitstring>>,C,Acc) ->
+ Octets = list_to_binary(lists:reverse(Acc)),
+ case C of
+ Int when is_integer(Int), C == size(Octets) ->
+ {Octets,Bin};
+ Int when is_integer(Int) ->
+ exit({error,{asn1,{illegal_value,C,Octets}}})
+ end;
+decode_fragmented_octets(<<0:1,Len:7,BitStr/bitstring>>,C,Acc) ->
+ <<Value:Len/binary-unit:8,BitStr2/binary>> = BitStr,
+ BinOctets = list_to_binary(lists:reverse([Value|Acc])),
+ case C of
+ Int when is_integer(Int),size(BinOctets) == Int ->
+ {BinOctets,BitStr2};
+ Int when is_integer(Int) ->
+ exit({error,{asn1,{illegal_value,C,BinOctets}}})
+ end.
+
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% encode_open_type(Constraint, Value) -> CompleteList
+%% Value = list of bytes of an already encoded value (the list must be flat)
+%% | binary
+%% Contraint = not used in this version
+%%
+encode_open_type(C, Val) when is_list(Val) ->
+ encode_open_type(C, list_to_binary(Val));
+encode_open_type(_C, Val) when is_binary(Val) ->
+ [encode_length(undefined,size(Val)),Val].
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% decode_open_type(Buffer,Constraint) -> Value
+%% Constraint is not used in this version
+%% Buffer = [byte] with PER encoded data
+%% Value = [byte] with decoded data (which must be decoded again as some type)
+%%
+decode_open_type(Bytes, _C) ->
+ {Len,Bytes2} = decode_length(Bytes,undefined),
+ getoctets_as_bin(Bytes2,Len).
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% encode_integer(Constraint,Value,NamedNumberList) -> CompleteList
+%% encode_integer(Constraint,Value) -> CompleteList
+%% encode_integer(Constraint,{Name,Value}) -> CompleteList
+%%
+%%
+encode_integer(C,V,NamedNumberList) when is_atom(V) ->
+ case lists:keysearch(V,1,NamedNumberList) of
+ {value,{_,NewV}} ->
+ encode_integer(C,NewV);
+ _ ->
+ exit({error,{asn1,{namednumber,V}}})
+ end;
+encode_integer(C,V,_NamedNumberList) when is_integer(V) ->
+ encode_integer(C,V);
+encode_integer(C,{Name,V},NamedNumberList) when is_atom(Name) ->
+ encode_integer(C,V,NamedNumberList).
+
+encode_integer(C,{Name,Val}) when is_atom(Name) ->
+ encode_integer(C,Val);
+
+encode_integer([{Rc,_Ec}],Val) when is_tuple(Rc) -> % XXX when is this invoked? First argument most often a list,...Ok this is the extension case...but it doesn't work.
+ case (catch encode_integer([Rc],Val)) of
+ {'EXIT',{error,{asn1,_}}} ->
+ [<<1:1>>,encode_unconstrained_number(Val)];
+ Encoded ->
+ [<<0:1>>,Encoded]
+ end;
+encode_integer(C,Val ) when is_list(C) ->
+ case get_constraint(C,'SingleValue') of
+ no ->
+ encode_integer1(C,Val);
+ V when is_integer(V),V == Val ->
+ []; % a type restricted to a single value encodes to nothing
+ V when is_list(V) ->
+ case lists:member(Val,V) of
+ true ->
+ encode_integer1(C,Val);
+ _ ->
+ exit({error,{asn1,{illegal_value,Val}}})
+ end;
+ _ ->
+ exit({error,{asn1,{illegal_value,Val}}})
+ end.
+
+encode_integer1(C, Val) ->
+ case VR = get_constraint(C,'ValueRange') of
+ no ->
+ encode_unconstrained_number(Val);
+ {Lb,'MAX'} ->
+ encode_semi_constrained_number(Lb,Val);
+ %% positive with range
+ {Lb,Ub} when Val >= Lb,
+ Ub >= Val ->
+ encode_constrained_number(VR,Val);
+ _ ->
+ exit({error,{asn1,{illegal_value,VR,Val}}})
+ end.
+
+decode_integer(Buffer,Range,NamedNumberList) ->
+ {Val,Buffer2} = decode_integer(Buffer,Range),
+ case lists:keysearch(Val,2,NamedNumberList) of
+ {value,{NewVal,_}} -> {NewVal,Buffer2};
+ _ -> {Val,Buffer2}
+ end.
+
+decode_integer(Buffer,[{Rc,_Ec}]) when is_tuple(Rc) ->
+ {Ext,Buffer2} = getext(Buffer),
+ case Ext of
+ 0 -> decode_integer(Buffer2,[Rc]); %% Value in root of constraint
+ 1 -> decode_unconstrained_number(Buffer2)
+ end;
+decode_integer(Buffer,undefined) ->
+ decode_unconstrained_number(Buffer);
+decode_integer(Buffer,C) ->
+ case get_constraint(C,'SingleValue') of
+ V when is_integer(V) ->
+ {V,Buffer};
+ V when is_list(V) ->
+ {Val,Buffer2} = decode_integer1(Buffer,C),
+ case lists:member(Val,V) of
+ true ->
+ {Val,Buffer2};
+ _ ->
+ exit({error,{asn1,{illegal_value,Val}}})
+ end;
+ _ ->
+ decode_integer1(Buffer,C)
+ end.
+
+decode_integer1(Buffer,C) ->
+ case VR = get_constraint(C,'ValueRange') of
+ no ->
+ decode_unconstrained_number(Buffer);
+ {Lb, 'MAX'} ->
+ decode_semi_constrained_number(Buffer,Lb);
+ {_,_} ->
+ decode_constrained_number(Buffer,VR)
+ end.
+
+%% X.691:10.6 Encoding of a normally small non-negative whole number
+%% Use this for encoding of CHOICE index if there is an extension marker in
+%% the CHOICE
+encode_small_number({Name,Val}) when is_atom(Name) ->
+ encode_small_number(Val);
+encode_small_number(Val) when Val =< 63 ->
+ <<Val:7>>;
+encode_small_number(Val) ->
+ [<<1:1>>,encode_semi_constrained_number(0,Val)].
+
+decode_small_number(Bytes) ->
+ {Bit,Bytes2} = getbit(Bytes),
+ case Bit of
+ 0 ->
+ getbits(Bytes2,6);
+ 1 ->
+ decode_semi_constrained_number(Bytes2,0)
+ end.
+
+%% X.691:10.7 Encoding of a semi-constrained whole number
+%% might be an optimization encode_semi_constrained_number(0,Val) ->
+encode_semi_constrained_number(C,{Name,Val}) when is_atom(Name) ->
+ encode_semi_constrained_number(C,Val);
+encode_semi_constrained_number({Lb,'MAX'},Val) ->
+ encode_semi_constrained_number(Lb,Val);
+encode_semi_constrained_number(Lb,Val) ->
+ %% encoding in minimum no of octets preceeded by a length
+ Val2 = Val - Lb,
+%% NumBits = num_bits(Val2),
+ Bin = eint_bin_positive(Val2),
+ Size = size(Bin),
+ if
+ Size < 128 ->
+ [<<Size>>,Bin]; % equiv with encode_length(undefined,Len) but faster
+ Size < 16384 ->
+ [<<2:2,Size:14>>,Bin];
+ true ->
+ [encode_length(undefined,Size),Bin]
+ end.
+
+decode_semi_constrained_number(Bytes,{Lb,_}) ->
+ decode_semi_constrained_number(Bytes,Lb);
+decode_semi_constrained_number(Bytes,Lb) ->
+ {Len,Bytes2} = decode_length(Bytes,undefined),
+ {V,Bytes3} = getoctets(Bytes2,Len),
+ {V+Lb,Bytes3}.
+
+encode_constrained_number(Range,{Name,Val}) when is_atom(Name) ->
+ encode_constrained_number(Range,Val);
+encode_constrained_number({Lb,Ub},Val) when Val >= Lb, Ub >= Val ->
+ Range = Ub - Lb + 1,
+ Val2 = Val - Lb,
+ NumBits = num_bits(Range),
+ <<Val2:NumBits>>;
+encode_constrained_number(Range,Val) ->
+ exit({error,{asn1,{integer_range,Range,value,Val}}}).
+
+
+decode_constrained_number(Buffer,{Lb,Ub}) ->
+ Range = Ub - Lb + 1,
+ NumBits = num_bits(Range),
+ {Val,Remain} = getbits(Buffer,NumBits),
+ {Val+Lb,Remain}.
+
+%% X.691:10.8 Encoding of an unconstrained whole number
+
+encode_unconstrained_number(Val) when Val >= 0 ->
+ Oct = eint_bin_2Cs(Val),
+ Len = size(Oct),
+ if
+ Len < 128 ->
+ [<<Len>>,Oct]; % equiv with encode_length(undefined,Len) but faster
+ Len < 16384 ->
+ [<<2:2,Len:14>>,Oct];
+ true ->
+ [encode_length(undefined,Len),<<Len:16>>,Oct]
+ end;
+encode_unconstrained_number(Val) -> % negative
+ Oct = enint(Val,[]),
+ Len = size(Oct),
+ if
+ Len < 128 ->
+ [<<Len>>,Oct]; % equiv with encode_length(undefined,Len) but faster
+ Len < 16384 ->
+ [<<2:2,Len:14>>,Oct];
+ true ->
+ [encode_length(undefined,Len),Oct]
+ end.
+
+
+eint_bin_2Cs(Int) ->
+ case eint_bin_positive(Int) of
+ Bin = <<B,_/binary>> when B > 16#7f ->
+ <<0,Bin/binary>>;
+ Bin -> Bin
+ end.
+
+%% returns the integer as a binary
+eint_bin_positive(Val) when Val < 16#100 ->
+ <<Val>>;
+eint_bin_positive(Val) when Val < 16#10000 ->
+ <<Val:16>>;
+eint_bin_positive(Val) when Val < 16#1000000 ->
+ <<Val:24>>;
+eint_bin_positive(Val) when Val < 16#100000000 ->
+ <<Val:32>>;
+eint_bin_positive(Val) ->
+ list_to_binary([eint_bin_positive2(Val bsr 32)|<<Val:32>>]).
+eint_bin_positive2(Val) when Val < 16#100 ->
+ <<Val>>;
+eint_bin_positive2(Val) when Val < 16#10000 ->
+ <<Val:16>>;
+eint_bin_positive2(Val) when Val < 16#1000000 ->
+ <<Val:24>>;
+eint_bin_positive2(Val) when Val < 16#100000000 ->
+ <<Val:32>>;
+eint_bin_positive2(Val) ->
+ [eint_bin_positive2(Val bsr 32)|<<Val:32>>].
+
+
+
+
+enint(-1, [B1|T]) when B1 > 127 ->
+ list_to_binary([B1|T]);
+enint(N, Acc) ->
+ enint(N bsr 8, [N band 16#ff|Acc]).
+
+decode_unconstrained_number(Bytes) ->
+ {Len,Bytes2} = decode_length(Bytes,undefined),
+ {Ints,Bytes3} = getoctets_as_bin(Bytes2,Len),
+ {dec_integer(Ints),Bytes3}.
+
+dec_integer(Bin = <<0:1,_:7,_/bitstring>>) ->
+ decpint(Bin);
+dec_integer(<<_:1,B:7,BitStr/bitstring>>) ->
+ Size = bit_size(BitStr),
+ <<I:Size>> = BitStr,
+ (-128 + B) bsl bit_size(BitStr) bor I.
+
+decpint(Bin) ->
+ Size = bit_size(Bin),
+ <<Int:Size>> = Bin,
+ Int.
+
+
+%% X.691:10.9 Encoding of a length determinant
+%%encode_small_length(undefined,Len) -> % null means no UpperBound
+%% encode_small_number(Len).
+
+%% X.691:10.9.3.5
+%% X.691:10.9.3.7
+encode_length(undefined,Len) -> % un-constrained
+ if
+ Len < 128 ->
+ <<Len>>;
+ Len < 16384 ->
+ <<2:2,Len:14>>;
+ true -> % should be able to endode length >= 16384
+ exit({error,{asn1,{encode_length,{nyi,above_16k}}}})
+ end;
+
+encode_length({0,'MAX'},Len) ->
+ encode_length(undefined,Len);
+encode_length(Vr={Lb,Ub},Len) when Ub =< 65535 ,Lb >= 0 -> % constrained
+ encode_constrained_number(Vr,Len);
+encode_length({Lb,_Ub},Len) when is_integer(Lb), Lb >= 0 -> % Ub > 65535
+ encode_length(undefined,Len);
+encode_length({Vr={Lb,Ub},Ext},Len)
+ when Ub =< 65535 ,Lb >= 0, Len=<Ub, is_list(Ext) ->
+ %% constrained extensible
+ [<<0:1>>,encode_constrained_number(Vr,Len)];
+encode_length({{Lb,_Ub},Ext},Len) when is_list(Ext) ->
+ [<<1:1>>,encode_semi_constrained_number(Lb,Len)];
+encode_length(SingleValue,_Len) when is_integer(SingleValue) ->
+ [].
+
+%% X.691 10.9.3.4 (only used for length of bitmap that prefixes extension
+%% additions in a sequence or set
+encode_small_length(Len) when Len =< 64 ->
+ <<(Len-1):7>>;
+encode_small_length(Len) ->
+ [<<1:1>>,encode_length(undefined,Len)].
+
+
+decode_small_length(Buffer) ->
+ case getbit(Buffer) of
+ {0,Remain} ->
+ {Bits,Remain2} = getbits(Remain,6),
+ {Bits+1,Remain2};
+ {1,Remain} ->
+ decode_length(Remain,undefined)
+ end.
+
+decode_length(Buffer) ->
+ decode_length(Buffer,undefined).
+
+%% un-constrained
+decode_length(<<0:1,Oct:7,Rest/bitstring>>,undefined) ->
+ {Oct,Rest};
+decode_length(<<2:2,Val:14,Rest/bitstring>>,undefined) ->
+ {Val,Rest};
+decode_length(<<3:2,_:14,_Rest/bitstring>>,undefined) ->
+ exit({error,{asn1,{decode_length,{nyi,above_16k}}}});
+
+decode_length(Buffer,{Lb,Ub}) when Ub =< 65535 ,Lb >= 0 -> % constrained
+ decode_constrained_number(Buffer,{Lb,Ub});
+decode_length(Buffer,{Lb,_}) when is_integer(Lb), Lb >= 0 -> % Ub > 65535
+ decode_length(Buffer,undefined);
+decode_length(Buffer,{VR={_Lb,_Ub},Ext}) when is_list(Ext) ->
+ {0,Buffer2} = getbit(Buffer),
+ decode_length(Buffer2, VR);
+
+
+%When does this case occur with {_,_Lb,Ub} ??
+% X.691:10.9.3.5
+decode_length(Bin,{_,_Lb,_Ub}) -> %when Len =< 127 -> % Unconstrained or large Ub NOTE! this case does not cover case when Ub > 65535
+ case Bin of
+ <<0:1,Val:7,Rest/bitstring>> ->
+ {Val,Rest};
+ <<2:2,Val:14,Rest/bitstring>> ->
+ {Val,Rest};
+ <<3:2,_:14,_Rest/bitstring>> ->
+ exit({error,{asn1,{decode_length,{nyi,length_above_64K}}}})
+ end;
+decode_length(Buffer,SingleValue) when is_integer(SingleValue) ->
+ {SingleValue,Buffer}.
+
+
+ % X.691:11
+encode_boolean(true) ->
+ <<1:1>>;
+encode_boolean(false) ->
+ <<0:1>>;
+encode_boolean({Name,Val}) when is_atom(Name) ->
+ encode_boolean(Val);
+encode_boolean(Val) ->
+ exit({error,{asn1,{encode_boolean,Val}}}).
+
+decode_boolean(Buffer) -> %when record(Buffer,buffer)
+ case getbit(Buffer) of
+ {1,Remain} -> {true,Remain};
+ {0,Remain} -> {false,Remain}
+ end.
+
+
+%% ENUMERATED with extension marker
+decode_enumerated(Buffer,C,{Ntup1,Ntup2}) when is_tuple(Ntup1), is_tuple(Ntup2) ->
+ {Ext,Buffer2} = getext(Buffer),
+ case Ext of
+ 0 -> % not an extension value
+ {Val,Buffer3} = decode_integer(Buffer2,C),
+ case catch (element(Val+1,Ntup1)) of
+ NewVal when is_atom(NewVal) -> {NewVal,Buffer3};
+ _Error -> exit({error,{asn1,{decode_enumerated,{Val,[Ntup1,Ntup2]}}}})
+ end;
+ 1 -> % this an extension value
+ {Val,Buffer3} = decode_small_number(Buffer2),
+ case catch (element(Val+1,Ntup2)) of
+ NewVal when is_atom(NewVal) -> {NewVal,Buffer3};
+ _ -> {{asn1_enum,Val},Buffer3}
+ end
+ end;
+
+decode_enumerated(Buffer,C,NamedNumberTup) when is_tuple(NamedNumberTup) ->
+ {Val,Buffer2} = decode_integer(Buffer,C),
+ case catch (element(Val+1,NamedNumberTup)) of
+ NewVal when is_atom(NewVal) -> {NewVal,Buffer2};
+ _Error -> exit({error,{asn1,{decode_enumerated,{Val,NamedNumberTup}}}})
+ end.
+
+
+%%============================================================================
+%%============================================================================
+%% Bitstring value, ITU_T X.690 Chapter 8.5
+%%============================================================================
+%%============================================================================
+
+%%============================================================================
+%% encode bitstring value
+%%============================================================================
+
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% bitstring NamedBitList
+%% Val can be of:
+%% - [identifiers] where only named identifers are set to one,
+%% the Constraint must then have some information of the
+%% bitlength.
+%% - [list of ones and zeroes] all bits
+%% - integer value representing the bitlist
+%% C is constraint Len, only valid when identifiers
+
+
+%% when the value is a list of {Unused,BinBits}, where
+%% Unused = integer(),
+%% BinBits = binary().
+
+encode_bit_string(C,Bin={Unused,BinBits},NamedBitList) when is_integer(Unused),
+ is_binary(BinBits) ->
+ encode_bin_bit_string(get_constraint(C,'SizeConstraint'),Bin,NamedBitList);
+
+encode_bit_string(C, BitListVal, NamedBitList) ->
+ encode_bit_string1(get_constraint(C,'SizeConstraint'), BitListVal, NamedBitList).
+%% when the value is a list of named bits
+encode_bit_string1(C, LoNB=[FirstVal | _RestVal], NamedBitList) when is_atom(FirstVal) ->
+ ToSetPos = get_all_bitposes(LoNB, NamedBitList, []),
+ BitList = make_and_set_list(ToSetPos,0),
+ encode_bit_string1(C,BitList,NamedBitList);
+
+encode_bit_string1(C, BL=[{bit,_No} | _RestVal], NamedBitList) ->
+ ToSetPos = get_all_bitposes(BL, NamedBitList, []),
+ BitList = make_and_set_list(ToSetPos,0),
+ encode_bit_string1(C,BitList,NamedBitList);
+%% when the value is a list of ones and zeroes
+encode_bit_string1(Int, BitListValue, _)
+ when is_list(BitListValue),is_integer(Int) ->
+ %% The type is constrained by a single value size constraint
+ bit_list2bitstr(Int,BitListValue);
+encode_bit_string1(no, BitListValue,[])
+ when is_list(BitListValue) ->
+ Len = length(BitListValue),
+ [encode_length(undefined,Len),bit_list2bitstr(Len,BitListValue)];
+encode_bit_string1(C, BitListValue,[])
+ when is_list(BitListValue) ->
+ Len = length(BitListValue),
+ [encode_length(C,Len),bit_list2bitstr(Len,BitListValue)];
+encode_bit_string1(no, BitListValue,_NamedBitList)
+ when is_list(BitListValue) ->
+ %% this case with an unconstrained BIT STRING can be made more efficient
+ %% if the complete driver can take a special code so the length field
+ %% is encoded there.
+ NewBitLVal = lists:reverse(lists:dropwhile(fun(0)->true;(1)->false end,
+ lists:reverse(BitListValue))),
+ Len = length(NewBitLVal),
+ [encode_length(undefined,Len),bit_list2bitstr(Len,NewBitLVal)];
+encode_bit_string1(C,BitListValue,_NamedBitList)
+ when is_list(BitListValue) ->% C = {_,'MAX'}
+ NewBitStr = bitstr_trailing_zeros(BitListValue,C),
+ [encode_length(C,bit_size(NewBitStr)),NewBitStr];
+
+
+%% when the value is an integer
+encode_bit_string1(C, IntegerVal, NamedBitList) when is_integer(IntegerVal)->
+ BitList = int_to_bitlist(IntegerVal),
+ encode_bit_string1(C,BitList,NamedBitList);
+
+%% when the value is a tuple
+encode_bit_string1(C,{Name,Val}, NamedBitList) when is_atom(Name) ->
+ encode_bit_string1(C,Val,NamedBitList).
+
+bit_list2bitstr(Len,BitListValue) ->
+ case length(BitListValue) of
+ Len ->
+ << <<B:1>> ||B <- BitListValue>>;
+ L when L > Len -> % truncate
+ << << <<B:1>> ||B <- BitListValue>> :Len/bitstring>>;
+ L -> % Len > L -> pad
+ << << <<B:1>> ||B <- BitListValue>>/bitstring ,0:(Len-L)>>
+ end.
+
+adjust_trailing_zeros(Len,Bin) when Len == bit_size(Bin) ->
+ Bin;
+adjust_trailing_zeros(Len,Bin) when Len > bit_size(Bin) ->
+ <<Bin/bitstring,0:(Len-bit_size(Bin))>>;
+adjust_trailing_zeros(Len,Bin) ->
+ <<Bin:Len/bitstring>>.
+
+bitstr_trailing_zeros(BitList,C) when is_integer(C) ->
+ bitstr_trailing_zeros1(BitList,C,C);
+bitstr_trailing_zeros(BitList,{Lb,Ub}) when is_integer(Lb) ->
+ bitstr_trailing_zeros1(BitList,Lb,Ub);
+bitstr_trailing_zeros(BitList,{{Lb,Ub},_}) when is_integer(Lb) ->
+ bitstr_trailing_zeros1(BitList,Lb,Ub);
+bitstr_trailing_zeros(BitList,_) ->
+ bit_list2bitstr(length(BitList),BitList).
+
+bitstr_trailing_zeros1(BitList,Lb,Ub) ->
+ case length(BitList) of
+ Lb -> bit_list2bitstr(Lb,BitList);
+ B when B<Lb -> bit_list2bitstr(Lb,BitList);
+ D -> F = fun(L,LB,LB,_,_)->bit_list2bitstr(LB,lists:reverse(L));
+ ([0|R],L1,LB,UB,Fun)->Fun(R,L1-1,LB,UB,Fun);
+ (L,L1,_,UB,_)when L1 =< UB ->
+ bit_list2bitstr(L1,lists:reverse(L));
+ (_,_L1,_,_,_) ->exit({error,{list_length_BIT_STRING,
+ BitList}}) end,
+ F(lists:reverse(BitList),D,Lb,Ub,F)
+ end.
+
+%% encode_bin_bit_string/3, when value is a tuple of Unused and BinBits.
+%% Unused = integer(),i.e. number unused bits in least sign. byte of
+%% BinBits = binary().
+encode_bin_bit_string(C,{_,BinBits},_NamedBitList)
+ when is_integer(C),C=<16 ->
+ adjust_trailing_zeros(C,BinBits);
+encode_bin_bit_string(C,{_Unused,BinBits},_NamedBitList)
+ when is_integer(C) ->
+ adjust_trailing_zeros(C,BinBits);
+encode_bin_bit_string(C,UnusedAndBin={_,_},NamedBitList) ->
+ %% removes all trailing bits if NamedBitList is not empty
+ BitStr = remove_trailing_bin(NamedBitList,UnusedAndBin),
+ case C of
+ {Lb,Ub} when is_integer(Lb),is_integer(Ub) ->
+ [encode_length({Lb,Ub},bit_size(BitStr)),BitStr];
+ no ->
+ [encode_length(undefined,bit_size(BitStr)),BitStr];
+ Sc ->
+ [encode_length(Sc,bit_size(BitStr)),BitStr]
+ end.
+
+
+remove_trailing_bin([], {Unused,Bin}) ->
+ BS = bit_size(Bin)-Unused,
+ <<BitStr:BS/bitstring,_:Unused>> = Bin,
+ BitStr;
+remove_trailing_bin(_NamedNumberList,{_Unused,<<>>}) ->
+ <<>>;
+remove_trailing_bin(NamedNumberList, {_Unused,Bin}) ->
+ Size = size(Bin)-1,
+ <<Bfront:Size/binary, LastByte:8>> = Bin,
+
+ %% clear the Unused bits to be sure
+ Unused1 = trailingZeroesInNibble(LastByte band 15),
+ Unused2 =
+ case Unused1 of
+ 4 ->
+ 4 + trailingZeroesInNibble(LastByte bsr 4);
+ _ -> Unused1
+ end,
+ case Unused2 of
+ 8 ->
+ remove_trailing_bin(NamedNumberList,{0,Bfront});
+ _ ->
+ BS = bit_size(Bin) - Unused2,
+ <<BitStr:BS/bitstring,_:Unused2>> = Bin,
+ BitStr
+ end.
+
+trailingZeroesInNibble(0) ->
+ 4;
+trailingZeroesInNibble(1) ->
+ 0;
+trailingZeroesInNibble(2) ->
+ 1;
+trailingZeroesInNibble(3) ->
+ 0;
+trailingZeroesInNibble(4) ->
+ 2;
+trailingZeroesInNibble(5) ->
+ 0;
+trailingZeroesInNibble(6) ->
+ 1;
+trailingZeroesInNibble(7) ->
+ 0;
+trailingZeroesInNibble(8) ->
+ 3;
+trailingZeroesInNibble(9) ->
+ 0;
+trailingZeroesInNibble(10) ->
+ 1;
+trailingZeroesInNibble(11) ->
+ 0;
+trailingZeroesInNibble(12) -> %#1100
+ 2;
+trailingZeroesInNibble(13) ->
+ 0;
+trailingZeroesInNibble(14) ->
+ 1;
+trailingZeroesInNibble(15) ->
+ 0.
+
+%%%%%%%%%%%%%%%
+%% The result is presented as a list of named bits (if possible)
+%% else as a tuple {Unused,Bits}. Unused is the number of unused
+%% bits, least significant bits in the last byte of Bits. Bits is
+%% the BIT STRING represented as a binary.
+%%
+decode_compact_bit_string(Buffer, C, NamedNumberList) ->
+ case get_constraint(C,'SizeConstraint') of
+ 0 -> % fixed length
+ {{8,0},Buffer};
+ V when is_integer(V),V=<16 -> %fixed length 16 bits or less
+ compact_bit_string(Buffer,V,NamedNumberList);
+ V when is_integer(V),V=<65536 -> %fixed length > 16 bits
+ compact_bit_string(Buffer,V,NamedNumberList);
+ V when is_integer(V) -> % V > 65536 => fragmented value
+ {Bin,Buffer2} = decode_fragmented_bits(Buffer,V),
+ PadLen = (8 - (bit_size(Bin) rem 8)) rem 8,
+ {{PadLen,<<Bin/bitstring,0:PadLen>>},Buffer2};
+%% {0,_} -> {{0,Bin},Buffer2};
+%% {U,_} -> {{8-U,Bin},Buffer2}
+ {Lb,Ub} when is_integer(Lb),is_integer(Ub) ->
+ %% This case may demand decoding of fragmented length/value
+ {Len,Bytes2} = decode_length(Buffer,{Lb,Ub}),
+ compact_bit_string(Bytes2,Len,NamedNumberList);
+ no ->
+ %% This case may demand decoding of fragmented length/value
+ {Len,Bytes2} = decode_length(Buffer,undefined),
+ compact_bit_string(Bytes2,Len,NamedNumberList);
+ Sc ->
+ {Len,Bytes2} = decode_length(Buffer,Sc),
+ compact_bit_string(Bytes2,Len,NamedNumberList)
+ end.
+
+
+%%%%%%%%%%%%%%%
+%% The result is presented as a list of named bits (if possible)
+%% else as a list of 0 and 1.
+%%
+decode_bit_string(Buffer, C, NamedNumberList) ->
+ case get_constraint(C,'SizeConstraint') of
+ {Lb,Ub} when is_integer(Lb),is_integer(Ub) ->
+ {Len,Bytes2} = decode_length(Buffer,{Lb,Ub}),
+ bit_list_or_named(Bytes2,Len,NamedNumberList);
+ no ->
+ {Len,Bytes2} = decode_length(Buffer,undefined),
+ bit_list_or_named(Bytes2,Len,NamedNumberList);
+ 0 -> % fixed length
+ {[],Buffer}; % nothing to encode
+ V when is_integer(V),V=<16 -> % fixed length 16 bits or less
+ bit_list_or_named(Buffer,V,NamedNumberList);
+ V when is_integer(V),V=<65536 ->
+ bit_list_or_named(Buffer,V,NamedNumberList);
+ V when is_integer(V) ->
+ {BinBits,_} = decode_fragmented_bits(Buffer,V),
+ bit_list_or_named(BinBits,V,NamedNumberList);
+ Sc -> % extension marker
+ {Len,Bytes2} = decode_length(Buffer,Sc),
+ bit_list_or_named(Bytes2,Len,NamedNumberList)
+ end.
+
+
+%% if no named bits are declared we will return a
+%% {Unused,Bits}. Unused = integer(),
+%% Bits = binary().
+compact_bit_string(Buffer,Len,[]) ->
+ {BitStr,Rest} = getbits_as_binary(Len,Buffer), % {{Unused,BinBits},NewBuffer}
+ PadLen = (8 - (bit_size(BitStr) rem 8)) rem 8,
+ {{PadLen,<<BitStr/bitstring,0:PadLen>>},Rest};
+compact_bit_string(Buffer,Len,NamedNumberList) ->
+ bit_list_or_named(Buffer,Len,NamedNumberList).
+
+
+%% if no named bits are declared we will return a
+%% BitList = [0 | 1]
+
+bit_list_or_named(Buffer,Len,[]) ->
+ getbits_as_list(Len,Buffer);
+
+%% if there are named bits declared we will return a named
+%% BitList where the names are atoms and unnamed bits represented
+%% as {bit,Pos}
+%% BitList = [atom() | {bit,Pos}]
+%% Pos = integer()
+
+bit_list_or_named(Buffer,Len,NamedNumberList) ->
+ {BitList,Rest} = getbits_as_list(Len,Buffer),
+ {bit_list_or_named1(0,BitList,NamedNumberList,[]), Rest}.
+
+bit_list_or_named1(Pos,[0|Bt],Names,Acc) ->
+ bit_list_or_named1(Pos+1,Bt,Names,Acc);
+bit_list_or_named1(Pos,[1|Bt],Names,Acc) ->
+ case lists:keysearch(Pos,2,Names) of
+ {value,{Name,_}} ->
+ bit_list_or_named1(Pos+1,Bt,Names,[Name|Acc]);
+ _ ->
+ bit_list_or_named1(Pos+1,Bt,Names,[{bit,Pos}|Acc])
+ end;
+bit_list_or_named1(_,[],_,Acc) ->
+ lists:reverse(Acc).
+
+
+
+%%%%%%%%%%%%%%%
+%%
+
+int_to_bitlist(Int) when is_integer(Int), Int > 0 ->
+ [Int band 1 | int_to_bitlist(Int bsr 1)];
+int_to_bitlist(0) ->
+ [].
+
+
+%%%%%%%%%%%%%%%%%%
+%% get_all_bitposes([list of named bits to set], named_bit_db, []) ->
+%% [sorted_list_of_bitpositions_to_set]
+
+get_all_bitposes([{bit,ValPos}|Rest], NamedBitList, Ack) ->
+ get_all_bitposes(Rest, NamedBitList, [ValPos | Ack ]);
+
+get_all_bitposes([Val | Rest], NamedBitList, Ack) ->
+ case lists:keysearch(Val, 1, NamedBitList) of
+ {value, {_ValName, ValPos}} ->
+ get_all_bitposes(Rest, NamedBitList, [ValPos | Ack]);
+ _ ->
+ exit({error,{asn1, {bitstring_namedbit, Val}}})
+ end;
+get_all_bitposes([], _NamedBitList, Ack) ->
+ lists:sort(Ack).
+
+%%%%%%%%%%%%%%%%%%
+%% make_and_set_list([list of positions to set to 1])->
+%% returns list with all in SetPos set.
+%% in positioning in list the first element is 0, the second 1 etc.., but
+%%
+
+make_and_set_list([XPos|SetPos], XPos) ->
+ [1 | make_and_set_list(SetPos, XPos + 1)];
+make_and_set_list([Pos|SetPos], XPos) ->
+ [0 | make_and_set_list([Pos | SetPos], XPos + 1)];
+make_and_set_list([], _) ->
+ [].
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% X.691:16
+%% encode_octet_string(Constraint,Val)
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+encode_octet_string(C,{_Name,Val}) ->
+ encode_octet_string(C,Val);
+encode_octet_string(C,Val) ->
+ case get_constraint(C,'SizeConstraint') of
+ 0 ->
+ <<>>;
+ 1 ->
+ list_to_binary(Val);
+ 2 ->
+ list_to_binary(Val);
+ Sv when Sv =<65535, Sv == length(Val) -> % fixed length
+ list_to_binary(Val);
+ VR = {_,_} ->
+ [encode_length(VR,length(Val)),list_to_binary(Val)];
+ Sv when is_list(Sv) ->
+ [encode_length({hd(Sv),lists:max(Sv)},length(Val)),list_to_binary(Val)];
+ no ->
+ [encode_length(undefined,length(Val)),list_to_binary(Val)]
+ end.
+
+decode_octet_string(Bytes,C) ->
+ decode_octet_string1(Bytes,get_constraint(C,'SizeConstraint')).
+decode_octet_string1(<<B1,Bytes/bitstring>>,1) ->
+ {[B1],Bytes};
+decode_octet_string1(<<B1,B2,Bytes/bitstring>>,2) ->
+ {[B1,B2],Bytes};
+decode_octet_string1(Bytes,Sv) when is_integer(Sv),Sv=<65535 ->
+ getoctets_as_list(Bytes,Sv);
+decode_octet_string1(Bytes,Sv) when is_integer(Sv) ->
+ decode_fragmented_octets(Bytes,Sv);
+decode_octet_string1(Bytes,{Lb,Ub}) ->
+ {Len,Bytes2} = decode_length(Bytes,{Lb,Ub}),
+ getoctets_as_list(Bytes2,Len);
+decode_octet_string1(Bytes,Sv) when is_list(Sv) ->
+ {Len,Bytes2} = decode_length(Bytes,{hd(Sv),lists:max(Sv)}),
+ getoctets_as_list(Bytes2,Len);
+decode_octet_string1(Bytes,no) ->
+ {Len,Bytes2} = decode_length(Bytes,undefined),
+ getoctets_as_list(Bytes2,Len).
+
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% Restricted char string types
+%% (NumericString, PrintableString,VisibleString,IA5String,BMPString,UniversalString)
+%% X.691:26 and X.680:34-36
+%%encode_restricted_string('BMPString',Constraints,Extension,Val)
+
+
+encode_restricted_string({Name,Val}) when is_atom(Name) ->
+ encode_restricted_string(Val);
+
+encode_restricted_string(Val) when is_list(Val)->
+ [encode_length(undefined,length(Val)),list_to_binary(Val)].
+
+encode_known_multiplier_string(StringType,C,{Name,Val}) when is_atom(Name) ->
+ encode_known_multiplier_string(StringType,C,Val);
+
+encode_known_multiplier_string(StringType,C,Val) ->
+ Result = chars_encode(C,StringType,Val),
+ NumBits = get_NumBits(C,StringType),
+ case get_constraint(C,'SizeConstraint') of
+ Ub when is_integer(Ub), Ub*NumBits =< 16 ->
+ Result;
+ 0 ->
+ [];
+ Ub when is_integer(Ub),Ub =<65535 -> % fixed length
+ Result;
+ {Ub,Lb} ->
+ [encode_length({Ub,Lb},length(Val)),Result];
+ Vl when is_list(Vl) ->
+ [encode_length({lists:min(Vl),lists:max(Vl)},length(Val)),Result];
+ no ->
+ [encode_length(undefined,length(Val)),Result]
+ end.
+
+decode_restricted_string(Bytes) ->
+ {Len,Bytes2} = decode_length(Bytes,undefined),
+ getoctets_as_list(Bytes2,Len).
+
+decode_known_multiplier_string(Bytes,StringType,C,_Ext) ->
+ NumBits = get_NumBits(C,StringType),
+ case get_constraint(C,'SizeConstraint') of
+ Ub when is_integer(Ub), Ub*NumBits =< 16 ->
+ chars_decode(Bytes,NumBits,StringType,C,Ub);
+ Ub when is_integer(Ub),Ub =<65535 -> % fixed length
+ chars_decode(Bytes,NumBits,StringType,C,Ub);
+ 0 ->
+ {[],Bytes};
+ Vl when is_list(Vl) ->
+ {Len,Bytes1} = decode_length(Bytes,{hd(Vl),lists:max(Vl)}),
+ chars_decode(Bytes1,NumBits,StringType,C,Len);
+ no ->
+ {Len,Bytes1} = decode_length(Bytes,undefined),
+ chars_decode(Bytes1,NumBits,StringType,C,Len);
+ {Lb,Ub}->
+ {Len,Bytes1} = decode_length(Bytes,{Lb,Ub}),
+ chars_decode(Bytes1,NumBits,StringType,C,Len)
+ end.
+
+
+encode_NumericString(C,Val) ->
+ encode_known_multiplier_string('NumericString',C,Val).
+decode_NumericString(Bytes,C) ->
+ decode_known_multiplier_string(Bytes,'NumericString',C,false).
+
+encode_PrintableString(C,Val) ->
+ encode_known_multiplier_string('PrintableString',C,Val).
+decode_PrintableString(Bytes,C) ->
+ decode_known_multiplier_string(Bytes,'PrintableString',C,false).
+
+encode_VisibleString(C,Val) -> % equivalent with ISO646String
+ encode_known_multiplier_string('VisibleString',C,Val).
+decode_VisibleString(Bytes,C) ->
+ decode_known_multiplier_string(Bytes,'VisibleString',C,false).
+
+encode_IA5String(C,Val) ->
+ encode_known_multiplier_string('IA5String',C,Val).
+decode_IA5String(Bytes,C) ->
+ decode_known_multiplier_string(Bytes,'IA5String',C,false).
+
+encode_BMPString(C,Val) ->
+ encode_known_multiplier_string('BMPString',C,Val).
+decode_BMPString(Bytes,C) ->
+ decode_known_multiplier_string(Bytes,'BMPString',C,false).
+
+encode_UniversalString(C,Val) ->
+ encode_known_multiplier_string('UniversalString',C,Val).
+decode_UniversalString(Bytes,C) ->
+ decode_known_multiplier_string(Bytes,'UniversalString',C,false).
+
+
+%% end of known-multiplier strings for which PER visible constraints are
+%% applied
+
+encode_GeneralString(_C,Val) ->
+ encode_restricted_string(Val).
+decode_GeneralString(Bytes,_C) ->
+ decode_restricted_string(Bytes).
+
+encode_GraphicString(_C,Val) ->
+ encode_restricted_string(Val).
+decode_GraphicString(Bytes,_C) ->
+ decode_restricted_string(Bytes).
+
+encode_ObjectDescriptor(_C,Val) ->
+ encode_restricted_string(Val).
+decode_ObjectDescriptor(Bytes) ->
+ decode_restricted_string(Bytes).
+
+encode_TeletexString(_C,Val) -> % equivalent with T61String
+ encode_restricted_string(Val).
+decode_TeletexString(Bytes,_C) ->
+ decode_restricted_string(Bytes).
+
+encode_VideotexString(_C,Val) ->
+ encode_restricted_string(Val).
+decode_VideotexString(Bytes,_C) ->
+ decode_restricted_string(Bytes).
+
+
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% getBMPChars(Bytes,Len) ->{BMPcharList,RemainingBytes}
+%%
+getBMPChars(Bytes,1) ->
+ {O1,Bytes2} = getbits(Bytes,8),
+ {O2,Bytes3} = getbits(Bytes2,8),
+ if
+ O1 == 0 ->
+ {[O2],Bytes3};
+ true ->
+ {[{0,0,O1,O2}],Bytes3}
+ end;
+getBMPChars(Bytes,Len) ->
+ getBMPChars(Bytes,Len,[]).
+
+getBMPChars(Bytes,0,Acc) ->
+ {lists:reverse(Acc),Bytes};
+getBMPChars(Bytes,Len,Acc) ->
+ {Octs,Bytes1} = getoctets_as_list(Bytes,2),
+ case Octs of
+ [0,O2] ->
+ getBMPChars(Bytes1,Len-1,[O2|Acc]);
+ [O1,O2]->
+ getBMPChars(Bytes1,Len-1,[{0,0,O1,O2}|Acc])
+ end.
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% chars_encode(C,StringType,Value) -> ValueList
+%%
+%% encodes chars according to the per rules taking the constraint PermittedAlphabet
+%% into account.
+%% This function does only encode the value part and NOT the length
+
+chars_encode(C,StringType,Value) ->
+ case {StringType,get_constraint(C,'PermittedAlphabet')} of
+ {'UniversalString',{_,_Sv}} ->
+ exit({error,{asn1,{'not implemented',"UniversalString with PermittedAlphabet constraint"}}});
+ {'BMPString',{_,_Sv}} ->
+ exit({error,{asn1,{'not implemented',"BMPString with PermittedAlphabet constraint"}}});
+ _ ->
+ {NumBits,CharOutTab} = {get_NumBits(C,StringType),get_CharOutTab(C,StringType)},
+ chars_encode2(Value,NumBits,CharOutTab)
+ end.
+
+chars_encode2([H|T],NumBits,{Min,Max,notab}) when H =< Max, H >= Min ->
+ %%[{bits,NumBits,H-Min}|chars_encode2(T,NumBits,{Min,Max,notab})];
+ [<<(H-Min):NumBits>>|chars_encode2(T,NumBits,{Min,Max,notab})];
+chars_encode2([H|T],NumBits,{Min,Max,Tab}) when H =< Max, H >= Min ->
+%% [{bits,NumBits,exit_if_false(H,element(H-Min+1,Tab))}|chars_encode2(T,NumBits,{Min,Max,Tab})];
+ Ch = exit_if_false(H,element(H-Min+1,Tab)),
+ [<<Ch:NumBits>>|chars_encode2(T,NumBits,{Min,Max,Tab})];
+chars_encode2([{A,B,C,D}|T],NumBits,{Min,Max,notab}) ->
+ %% no value range check here (ought to be, but very expensive)
+%% [{bits,NumBits,((((((A bsl 8)+B) bsl 8)+C) bsl 8)+D)-Min}|chars_encode2(T,NumBits,{Min,Max,notab})];
+ Ch = ((((((A bsl 8)+B) bsl 8)+C) bsl 8)+D)-Min,
+ [<<Ch:NumBits>>|chars_encode2(T,NumBits,{Min,Max,notab})];
+chars_encode2([{A,B,C,D}|T],NumBits,{Min,Max,Tab}) ->
+ %% no value range check here (ought to be, but very expensive)
+%% [{bits,NumBits,exit_if_false({A,B,C,D},element(((((((A bsl 8)+B) bsl 8)+C) bsl 8)+D)-Min,Tab))}|chars_encode2(T,NumBits,{Min,Max,notab})];
+ Ch = exit_if_false({A,B,C,D},element(((((((A bsl 8)+B) bsl 8)+C) bsl 8)+D)-Min,Tab)),
+ [<<Ch:NumBits>>|chars_encode2(T,NumBits,{Min,Max,notab})];
+chars_encode2([H|_T],_,{_,_,_}) ->
+ exit({error,{asn1,{illegal_char_value,H}}});
+chars_encode2([],_,_) ->
+ [].
+
+exit_if_false(V,false)->
+ exit({error,{asn1,{"illegal value according to Permitted alphabet constraint",V}}});
+exit_if_false(_,V) ->V.
+
+
+get_NumBits(C,StringType) ->
+ case get_constraint(C,'PermittedAlphabet') of
+ {'SingleValue',Sv} ->
+ charbits(length(Sv));
+ no ->
+ case StringType of
+ 'IA5String' ->
+ charbits(128); % 16#00..16#7F
+ 'VisibleString' ->
+ charbits(95); % 16#20..16#7E
+ 'PrintableString' ->
+ charbits(74); % [$\s,$',$(,$),$+,$,,$-,$.,$/,"0123456789",$:,$=,$?,$A..$Z,$a..$z
+ 'NumericString' ->
+ charbits(11); % $ ,"0123456789"
+ 'UniversalString' ->
+ 32;
+ 'BMPString' ->
+ 16
+ end
+ end.
+
+get_CharOutTab(C,StringType) ->
+ get_CharTab(C,StringType,out).
+
+get_CharInTab(C,StringType) ->
+ get_CharTab(C,StringType,in).
+
+get_CharTab(C,StringType,InOut) ->
+ case get_constraint(C,'PermittedAlphabet') of
+ {'SingleValue',Sv} ->
+ get_CharTab2(C,StringType,hd(Sv),lists:max(Sv),Sv,InOut);
+ no ->
+ case StringType of
+ 'IA5String' ->
+ {0,16#7F,notab};
+ 'VisibleString' ->
+ get_CharTab2(C,StringType,16#20,16#7F,notab,InOut);
+ 'PrintableString' ->
+ Chars = lists:sort(
+ " '()+,-./0123456789:=?ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"),
+ get_CharTab2(C,StringType,hd(Chars),lists:max(Chars),Chars,InOut);
+ 'NumericString' ->
+ get_CharTab2(C,StringType,16#20,$9," 0123456789",InOut);
+ 'UniversalString' ->
+ {0,16#FFFFFFFF,notab};
+ 'BMPString' ->
+ {0,16#FFFF,notab}
+ end
+ end.
+
+get_CharTab2(C,StringType,Min,Max,Chars,InOut) ->
+ BitValMax = (1 bsl get_NumBits(C,StringType))-1,
+ if
+ Max =< BitValMax ->
+ {0,Max,notab};
+ true ->
+ case InOut of
+ out ->
+ {Min,Max,create_char_tab(Min,Chars)};
+ in ->
+ {Min,Max,list_to_tuple(Chars)}
+ end
+ end.
+
+create_char_tab(Min,L) ->
+ list_to_tuple(create_char_tab(Min,L,0)).
+create_char_tab(Min,[Min|T],V) ->
+ [V|create_char_tab(Min+1,T,V+1)];
+create_char_tab(_Min,[],_V) ->
+ [];
+create_char_tab(Min,L,V) ->
+ [false|create_char_tab(Min+1,L,V)].
+
+%% See Table 20.3 in Dubuisson
+charbits(NumOfChars) when NumOfChars =< 2 -> 1;
+charbits(NumOfChars) when NumOfChars =< 4 -> 2;
+charbits(NumOfChars) when NumOfChars =< 8 -> 3;
+charbits(NumOfChars) when NumOfChars =< 16 -> 4;
+charbits(NumOfChars) when NumOfChars =< 32 -> 5;
+charbits(NumOfChars) when NumOfChars =< 64 -> 6;
+charbits(NumOfChars) when NumOfChars =< 128 -> 7;
+charbits(NumOfChars) when NumOfChars =< 256 -> 8;
+charbits(NumOfChars) when NumOfChars =< 512 -> 9;
+charbits(NumOfChars) when NumOfChars =< 1024 -> 10;
+charbits(NumOfChars) when NumOfChars =< 2048 -> 11;
+charbits(NumOfChars) when NumOfChars =< 4096 -> 12;
+charbits(NumOfChars) when NumOfChars =< 8192 -> 13;
+charbits(NumOfChars) when NumOfChars =< 16384 -> 14;
+charbits(NumOfChars) when NumOfChars =< 32768 -> 15;
+charbits(NumOfChars) when NumOfChars =< 65536 -> 16;
+charbits(NumOfChars) when is_integer(NumOfChars) ->
+ 16 + charbits1(NumOfChars bsr 16).
+
+charbits1(0) ->
+ 0;
+charbits1(NumOfChars) ->
+ 1 + charbits1(NumOfChars bsr 1).
+
+
+chars_decode(Bytes,_,'BMPString',C,Len) ->
+ case get_constraint(C,'PermittedAlphabet') of
+ no ->
+ getBMPChars(Bytes,Len);
+ _ ->
+ exit({error,{asn1,
+ {'not implemented',
+ "BMPString with PermittedAlphabet constraint"}}})
+ end;
+chars_decode(Bytes,NumBits,StringType,C,Len) ->
+ CharInTab = get_CharInTab(C,StringType),
+ chars_decode2(Bytes,CharInTab,NumBits,Len).
+
+
+chars_decode2(Bytes,CharInTab,NumBits,Len) ->
+ chars_decode2(Bytes,CharInTab,NumBits,Len,[]).
+
+chars_decode2(Bytes,_CharInTab,_NumBits,0,Acc) ->
+ {lists:reverse(Acc),Bytes};
+chars_decode2(Bytes,{Min,Max,notab},NumBits,Len,Acc) when NumBits > 8 ->
+ {Char,Bytes2} = getbits(Bytes,NumBits),
+ Result =
+ if
+ Char < 256 -> Char;
+ true ->
+ list_to_tuple(binary_to_list(<<Char:32>>))
+ end,
+ chars_decode2(Bytes2,{Min,Max,notab},NumBits,Len -1,[Result|Acc]);
+chars_decode2(Bytes,{Min,Max,notab},NumBits,Len,Acc) ->
+ {Char,Bytes2} = getbits(Bytes,NumBits),
+ chars_decode2(Bytes2,{Min,Max,notab},NumBits,Len -1,[Char+Min|Acc]);
+
+%% BMPString and UniversalString with PermittedAlphabet is currently not supported
+chars_decode2(Bytes,{Min,Max,CharInTab},NumBits,Len,Acc) ->
+ {Char,Bytes2} = getbits(Bytes,NumBits),
+ chars_decode2(Bytes2,{Min,Max,CharInTab},NumBits,Len -1,[element(Char+1,CharInTab)|Acc]).
+
+
+%% UTF8String
+encode_UTF8String(Val) when is_binary(Val) ->
+ [encode_length(undefined,size(Val)),Val];
+encode_UTF8String(Val) ->
+ Bin = list_to_binary(Val),
+ encode_UTF8String(Bin).
+
+decode_UTF8String(Bytes) ->
+ {Len,Bytes2} = decode_length(Bytes,undefined),
+ getoctets_as_bin(Bytes2,Len).
+
+
+ % X.691:17
+encode_null(_) -> []. % encodes to nothing
+
+decode_null(Bytes) ->
+ {'NULL',Bytes}.
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% encode_object_identifier(Val) -> CompleteList
+%% encode_object_identifier({Name,Val}) -> CompleteList
+%% Val -> {Int1,Int2,...,IntN} % N >= 2
+%% Name -> atom()
+%% Int1 -> integer(0..2)
+%% Int2 -> integer(0..39) when Int1 (0..1) else integer()
+%% Int3-N -> integer()
+%% CompleteList -> [binary()|bitstring()|list()]
+%%
+encode_object_identifier({Name,Val}) when is_atom(Name) ->
+ encode_object_identifier(Val);
+encode_object_identifier(Val) ->
+ OctetList = e_object_identifier(Val),
+ Octets = list_to_binary(OctetList), % performs a flatten at the same time
+ [encode_length(undefined,size(Octets)),Octets].
+
+%% This code is copied from asn1_encode.erl (BER) and corrected and modified
+
+e_object_identifier({'OBJECT IDENTIFIER',V}) ->
+ e_object_identifier(V);
+e_object_identifier({Cname,V}) when is_atom(Cname),is_tuple(V) ->
+ e_object_identifier(tuple_to_list(V));
+e_object_identifier({Cname,V}) when is_atom(Cname),is_list(V) ->
+ e_object_identifier(V);
+e_object_identifier(V) when is_tuple(V) ->
+ e_object_identifier(tuple_to_list(V));
+
+%% E1 = 0|1|2 and (E2 < 40 when E1 = 0|1)
+e_object_identifier([E1,E2|Tail]) when E1 >= 0, E1 < 2, E2 < 40 ; E1==2 ->
+ Head = 40*E1 + E2, % weird
+ e_object_elements([Head|Tail],[]);
+e_object_identifier(Oid=[_,_|_Tail]) ->
+ exit({error,{asn1,{'illegal_value',Oid}}}).
+
+e_object_elements([],Acc) ->
+ lists:reverse(Acc);
+e_object_elements([H|T],Acc) ->
+ e_object_elements(T,[e_object_element(H)|Acc]).
+
+e_object_element(Num) when Num < 128 ->
+ [Num];
+e_object_element(Num) ->
+ [e_o_e(Num bsr 7)|[Num band 2#1111111]].
+e_o_e(Num) when Num < 128 ->
+ Num bor 2#10000000;
+e_o_e(Num) ->
+ [e_o_e(Num bsr 7)|[(Num band 2#1111111) bor 2#10000000]].
+
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% decode_object_identifier(Bytes) -> {ObjId,RemainingBytes}
+%% ObjId -> {integer(),integer(),...} % at least 2 integers
+%% RemainingBytes -> [integer()] when integer() (0..255)
+decode_object_identifier(Bytes) ->
+ {Len,Bytes2} = decode_length(Bytes,undefined),
+ {Octs,Bytes3} = getoctets_as_list(Bytes2,Len),
+ [First|Rest] = dec_subidentifiers(Octs,0,[]),
+ Idlist = if
+ First < 40 ->
+ [0,First|Rest];
+ First < 80 ->
+ [1,First - 40|Rest];
+ true ->
+ [2,First - 80|Rest]
+ end,
+ {list_to_tuple(Idlist),Bytes3}.
+
+dec_subidentifiers([H|T],Av,Al) when H >=16#80 ->
+ dec_subidentifiers(T,(Av bsl 7) + (H band 16#7F),Al);
+dec_subidentifiers([H|T],Av,Al) ->
+ dec_subidentifiers(T,0,[(Av bsl 7) + H |Al]);
+dec_subidentifiers([],_Av,Al) ->
+ lists:reverse(Al).
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% encode_relative_oid(Val) -> CompleteList
+%% encode_relative_oid({Name,Val}) -> CompleteList
+encode_relative_oid({Name,Val}) when is_atom(Name) ->
+ encode_relative_oid(Val);
+encode_relative_oid(Val) when is_tuple(Val) ->
+ encode_relative_oid(tuple_to_list(Val));
+encode_relative_oid(Val) when is_list(Val) ->
+ Octets = list_to_binary([e_object_element(X)||X <- Val]),
+ [encode_length(undefined,size(Octets)),Octets].
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% decode_relative_oid(Val) -> CompleteList
+%% decode_relative_oid({Name,Val}) -> CompleteList
+decode_relative_oid(Bytes) ->
+ {Len,Bytes2} = decode_length(Bytes,undefined),
+ {Octs,Bytes3} = getoctets_as_list(Bytes2,Len),
+ ObjVals = dec_subidentifiers(Octs,0,[]),
+ {list_to_tuple(ObjVals),Bytes3}.
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% encode_real(Val) -> CompleteList
+%% encode_real({Name,Val}) -> CompleteList
+encode_real({Name,Val}) when is_atom(Name) ->
+ encode_real(Val);
+encode_real(Real) ->
+ {EncVal,Len} = ?RT_COMMON:encode_real([],Real),
+ [encode_length(undefined,Len),EncVal].
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% decode_real(Val) -> {REALvalue,Rest}
+%% decode_real({Name,Val}) -> {REALvalue,Rest}
+decode_real(Bytes) ->
+ {Len,Bytes2} = decode_length(Bytes,undefined),
+ <<Bytes3:Len/binary,Rest/bitstring>> = Bytes2,
+ {RealVal,Rest,Len} = ?RT_COMMON:decode_real(Bytes3,Len),
+ {RealVal,Rest}.
+
+
+get_constraint([{Key,V}],Key) ->
+ V;
+get_constraint([],_Key) ->
+ no;
+get_constraint(C,Key) ->
+ case lists:keysearch(Key,1,C) of
+ false ->
+ no;
+ {value,{_,V}} ->
+ V
+ end.
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% complete(InList) -> ByteList
+%% Takes a coded list with bits and bytes and converts it to a list of bytes
+%% Should be applied as the last step at encode of a complete ASN.1 type
+%%
+complete(InList) when is_list(InList) ->
+ case complete1(InList) of
+ <<>> ->
+ <<0>>;
+ Res ->
+ case bit_size(Res) band 7 of
+ 0 -> Res;
+ Bits -> <<Res/bitstring,0:(8-Bits)>>
+ end
+ end;
+complete(InList) when is_binary(InList) ->
+ InList;
+complete(InList) when is_bitstring(InList) ->
+ PadLen = 8 - (bit_size(InList) band 7),
+ <<InList/bitstring,0:PadLen>>.
+
+complete1(L) when is_list(L) ->
+ list_to_bitstring(L).
+
+%% Special version of complete that does not align the completed message.
+complete_NFP(InList) when is_list(InList) ->
+ list_to_bitstring(InList);
+complete_NFP(InList) when is_bitstring(InList) ->
+ InList.
+
+%% unaligned helpers
+
+%% 10.5.6 NOTE: If "range" satisfies the inequality 2^m < "range" =<
+%% 2^(m+1) then the number of bits = m + 1
+num_bits(1) -> 0;
+num_bits(2) -> 1;
+num_bits(R) when R =< 4 ->
+ 2;
+num_bits(R) when R =< 8 ->
+ 3;
+num_bits(R) when R =< 16 ->
+ 4;
+num_bits(R) when R =< 32 ->
+ 5;
+num_bits(R) when R =< 64 ->
+ 6;
+num_bits(R) when R =< 128 ->
+ 7;
+num_bits(R) when R =< 256 ->
+ 8;
+num_bits(R) when R =< 512 ->
+ 9;
+num_bits(R) when R =< 1024 ->
+ 10;
+num_bits(R) ->
+ 1+num_bits(R bsr 1).