I think there's an endianness problem in ospf_lsupd_receive. On the lines where the program checks lsa->type or uses the LSA_SCOPE macro, it has not previously converted lsa->type to host representation. I saw this problem as I created a new LSA class with type BFF0, which has area scope. It was incorrectly displaying "<WARN> Received LSA with invalid scope" messages and refusing to add the LSAs to the database. I checked and at the line 513, if ((LSA_SCOPE(lsa) == LSA_SCOPE_RES)) was evaluating as true because lsa->type was F0BF, which is a reserved type. All the other LSA types are also inverted, but it doesn't pose a problem for the common LSA types as their first hex digit is usually 0 if they are misrepresented (0800 for link LSA, 0120 for router LSA etc).