diff options
| -rw-r--r-- | lib/asn1/src/asn1ct_imm.erl | 57 |
1 files changed, 33 insertions, 24 deletions
diff --git a/lib/asn1/src/asn1ct_imm.erl b/lib/asn1/src/asn1ct_imm.erl index bf362db843..a7e62e061b 100644 --- a/lib/asn1/src/asn1ct_imm.erl +++ b/lib/asn1/src/asn1ct_imm.erl @@ -115,25 +115,15 @@ per_dec_named_integer(Constraint, NamedList0, Aligned) -> per_dec_k_m_string(StringType, Constraint, Aligned) -> SzConstr = effective_constraint(bitstring, Constraint), N = string_num_bits(StringType, Constraint, Aligned), - %% X.691 (07/2002) 27.5.7 says if the upper bound times the number - %% of bits is greater than or equal to 16, then the bit field should - %% be aligned. - Imm = dec_string(SzConstr, N, Aligned, fun(_, Ub) -> Ub >= 16 end), + Imm = dec_string(SzConstr, N, Aligned, k_m_string), Chars = char_tab(Constraint, StringType, N), convert_string(N, Chars, Imm). per_dec_octet_string(Constraint, Aligned) -> - dec_string(Constraint, 8, Aligned, - %% Aligned unless the size is fixed and =< 16. - fun(Sv, Sv) -> Sv > 16; - (_, _) -> true - end). + dec_string(Constraint, 8, Aligned, 'OCTET STRING'). per_dec_raw_bitstring(Constraint, Aligned) -> - dec_string(Constraint, 1, Aligned, - fun(Sv, Sv) -> Sv > 16; - (_, _) -> true - end). + dec_string(Constraint, 1, Aligned, 'BIT STRING'). per_dec_open_type(Aligned) -> {get_bits,decode_unconstrained_length(true, Aligned), @@ -157,21 +147,40 @@ per_dec_restricted_string(Aligned) -> %%% Local functions. %%% -dec_string(Sv, U, Aligned0, AF) when is_integer(Sv) -> +%% is_aligned(StringType, LowerBound, UpperBound) -> boolean() +%% StringType = 'OCTET STRING' | 'BIT STRING' | k_m_string +%% LowerBound = UpperBound = number of bits +%% Determine whether a string should be aligned in PER. + +is_aligned(T, Lb, Ub) when T =:= 'OCTET STRING'; T =:= 'BIT STRING' -> + %% OCTET STRINGs and BIT STRINGs are aligned to a byte boundary + %% unless the size is fixed and less than or equal to 16 bits. + Lb =/= Ub orelse Lb > 16; +is_aligned(k_m_string, _Lb, Ub) -> + %% X.691 (07/2002) 27.5.7 says if the upper bound times the number + %% of bits is greater than or equal to 16, then the bit field should + %% be aligned. + Ub >= 16. + +%%% +%%% Generating the intermediate format format for decoding. +%%% + +dec_string(Sv, U, Aligned0, T) when is_integer(Sv) -> Bits = U*Sv, - Aligned = Aligned0 andalso AF(Bits, Bits), + Aligned = Aligned0 andalso is_aligned(T, Bits, Bits), {get_bits,Sv,[U,binary,{align,Aligned}]}; -dec_string({{Sv,Sv},[]}, U, Aligned, AF) -> - bit_case(dec_string(Sv, U, Aligned, AF), - dec_string(no, U, Aligned, AF)); -dec_string({{_,_}=C,[]}, U, Aligned, AF) -> - bit_case(dec_string(C, U, Aligned, AF), - dec_string(no, U, Aligned, AF)); -dec_string({Lb,Ub}, U, Aligned0, AF) -> +dec_string({{Sv,Sv},[]}, U, Aligned, T) -> + bit_case(dec_string(Sv, U, Aligned, T), + dec_string(no, U, Aligned, T)); +dec_string({{_,_}=C,[]}, U, Aligned, T) -> + bit_case(dec_string(C, U, Aligned, T), + dec_string(no, U, Aligned, T)); +dec_string({Lb,Ub}, U, Aligned0, T) -> Len = per_dec_constrained(Lb, Ub, Aligned0), - Aligned = Aligned0 andalso AF(Lb*U, Ub*U), + Aligned = Aligned0 andalso is_aligned(T, Lb*U, Ub*U), {get_bits,Len,[U,binary,{align,Aligned}]}; -dec_string(_, U, Aligned, _AF) -> +dec_string(_, U, Aligned, _T) -> Al = [{align,Aligned}], DecRest = fun(V, Buf) -> asn1ct_func:call(per_common, |