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ASN1_ITEM_NEW(3) DragonFly Library Functions Manual ASN1_ITEM_NEW(3)
ASN1_item_new, ASN1_item_free -- generic ASN.1 value constructor and
ASN1_item_new(const ASN1_ITEM *it);
ASN1_item_free(ASN1_VALUE *val_in, const ASN1_ITEM *it);
ASN1_item_new() allocates and initializes an empty ASN.1 value of the
type described by the global static object it.
If the item type described by it is reference counted, ASN1_item_free()
decrements the reference count of val_in. Otherwise, or if the reference
count reaches 0, ASN1_item_free() frees val_in, assuming that it is of
the type described by it. If the true type of val_in fails to match the
specified it, buffer overflows and segmentation faults are likely to
occur. It is not possible to recover the type of an ASN1_VALUE object by
inspecting it; the type always needs to be remembered separately.
ASN1_VALUE is an incomplete type, and pointers to it always require cast-
ing to the correct complete type before they can be dereferenced. For
all practical purposes, a pointer to ASN1_VALUE is equivalent to a void
Depending on it, there are more than 150 different types that
ASN1_item_new() may return. Most of them are pointers to structures or
pointers to arrays of structures, but there are a few exceptions, for
example: If it is ASN1_NULL_it, ASN1_item_new() returns a specific
invalid pointer representing the unique ASN1_NULL object. If it is
ASN1_BOOLEAN_it or LONG_it, ASN1_item_new() does not return a pointer at
all, but a long value cast to ASN1_VALUE *.
ASN1_item_new() returns the new ASN1_VALUE object or NULL if an error
ASN1_item_d2i(3), ASN1_TYPE_new(3), d2i_ASN1_NULL(3), OBJ_nid2obj(3)
ASN1_item_new() and ASN1_item_free() first appeared in OpenSSL 0.9.7 and
have been available since OpenBSD 3.2.
The ASN1_VALUE type compromises type safety and invites programming mis-
takes that will typically have severe consequences.
DragonFly 5.5 March 22, 2018 DragonFly 5.5