What are the OBJECT IDENTIFIER values that are allowed by the standard and how are they encoded?

The OBJECT IDENTIFIER cannot have arbitrary values for the first 2 arcs. The first arc can be ONLY 0, 1 and 2. The second arc cannot exceed 4 if the first arc is 0 and cannot exceed 3 if the first arc is 1. The minimum number of arcs in OBJECT IDENTIFIER values is 2.

A number of protocols were created violating the above standard rules. So to compile erroneously written ASN.1, we introduced the ASN.1 compiler command line option -allowbadvalues which allows bad value notation like:

{0 9 2342 19200300 100 1 2}

Keep in mind that in contrast to the encoder, the decoder is not concerned if you pass a valid arc or not. Very often the problem is that one of the arcs exceeds the maximum value for a given ASN.1 compiler generated OBJECT IDENTIFIER representation, like a linked list for example:

typedef struct ObjectID {
struct ObjectID *next;
unsigned short value;
} *ObjectID;

In such a case, the arc 19200300 would not fit into a short integer representation and you would need to use the following directive along with the -allowbadvalues command line option to force generation of unsigned long instead:

--<OSS.OBJECTID LONG>--
D DEFINITIONS ::= BEGIN
P ::= OBJECT IDENTIFIER
p P ::= {0 9 2342 19200300 100 1 25}
END

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