Correct encoding (decoding) of lengths less than the root range

Given the type:

  S ::= IA5String (SIZE (5, ...))

attempting to encode (to PER/UPER) a string shorter than 5 characters
would fail. Similarly, attempting to decode such string in the BER
format would fail.

In the case of BER, we can do no range checks if the size constraint
is extensible.

2 files changed, 18 insertions, 0 deletions

diff --git a/lib/asn1/test/asn1_SUITE_data/Constraints.py b/lib/asn1/test/asn1_SUITE_data/Constraints.py
index 87243121f7..a069364084 100644
--- a/lib/asn1/test/asn1_SUITE_data/Constraints.py
+++ b/lib/asn1/test/asn1_SUITE_data/Constraints.py
@@ -86,5 +86,6 @@ Document ::= OCTET STRING (ENCODED BY pdf)
 
 pdf OBJECT IDENTIFIER ::= {1,2,3,4,5}
 
+ShorterExt ::= IA5String (SIZE (5, ...))
 
 END
diff --git a/lib/asn1/test/testConstraints.erl b/lib/asn1/test/testConstraints.erl
index d6db1c2b91..d245f6d1d5 100644
--- a/lib/asn1/test/testConstraints.erl
+++ b/lib/asn1/test/testConstraints.erl
@@ -145,8 +145,16 @@ int_constraints(Rules) ->
     [roundtrip('VariableSize', lists:seq($A, $A+L-1)) ||
 	L <- lists:seq(1, 10)],
 
+    roundtrip_enc('ShorterExt', "a", shorter_ext(Rules, "a")),
+    roundtrip('ShorterExt', "abcde"),
+    roundtrip('ShorterExt', "abcdef"),
+
     ok.
 
+shorter_ext(per, "a") -> <<16#80,16#01,16#61>>;
+shorter_ext(uper, "a") -> <<16#80,16#E1>>;
+shorter_ext(ber, _) -> none.
+
 refed_NNL_name(_Erule) ->
     ?line {ok,_} = asn1_wrapper:encode('Constraints','AnotherThing',fred),
     ?line {error,_Reason} = 
@@ -160,6 +168,15 @@ roundtrip(Module, Type, Value) ->
     {ok,Value} = Module:decode(Type, Encoded),
     ok.
 
+roundtrip_enc(Type, Value, Enc) ->
+    Module = 'Constraints',
+    {ok,Encoded} = Module:encode(Type, Value),
+    {ok,Value} = Module:decode(Type, Encoded),
+    case Enc of
+	none -> ok;
+	Encoded -> ok
+    end.
+
 range_error(ber, Type, Value) ->
     %% BER: Values outside the effective range should be rejected
     %% on decode.