Oscar Jacobsson
2013-05-13 09:19:41 UTC
Hi!
The ASN1InputStream implementation currently re-uses a set of shared buffers (byte[][] tmpBuffers) when parsing DerBooleans, DerEnumerateds and DerObjectIdentifiers.
One problem with this approach is that the constructor for DerEnumerated that takes a byte[] as its argument only stores a reference to the byte[] without actually copying the data, meaning should another DerBoolean, DerEnumerated or DerObjectIdentifier with the same length occur in the type being parsed, the DerEnumerated value will be overwritten, since the same shared buffer is re-used.
I stumbled upon this when trying to parse a SEQUENCE containing first an ENUMERATED and then a false BOOLEAN. The enum would always end up as 0, no matter which value was used.
The simplest solution would be to simple copy the input array in the DerEnumerated constructor (which is what the DerObjectIdentifier constructor does), but I'm not sure if that would be the optimal approach, since that would effectively be "working around" the optimization with the temp buffers.
Best regards,
Oscar Jacobsson
The ASN1InputStream implementation currently re-uses a set of shared buffers (byte[][] tmpBuffers) when parsing DerBooleans, DerEnumerateds and DerObjectIdentifiers.
One problem with this approach is that the constructor for DerEnumerated that takes a byte[] as its argument only stores a reference to the byte[] without actually copying the data, meaning should another DerBoolean, DerEnumerated or DerObjectIdentifier with the same length occur in the type being parsed, the DerEnumerated value will be overwritten, since the same shared buffer is re-used.
I stumbled upon this when trying to parse a SEQUENCE containing first an ENUMERATED and then a false BOOLEAN. The enum would always end up as 0, no matter which value was used.
The simplest solution would be to simple copy the input array in the DerEnumerated constructor (which is what the DerObjectIdentifier constructor does), but I'm not sure if that would be the optimal approach, since that would effectively be "working around" the optimization with the temp buffers.
Best regards,
Oscar Jacobsson