A pure Python package for querying information from FlexNet license servers.
This acts as a "read-only" client for real-time license status and usage
information, like the native lmstat binary provides. See the ManagerClient
class in the client module for a starting point. This is currently a tangled
mess of unfinished code, but I wanted to make sure it was available if it could
be helpful for others, as it does contain some details of the querying methods
for the FlexNet protocol I couldn't find anywhere else (before figuring them
out).
The intent was to create a tool to help with the centralized management of a diverse set of license servers, possibly running on different hosts with different license managers and versions (as this is currently a bit of a PITA). This does not attempt any "write" operations like checking out or releasing a license.
tcpdump and Wireshark were used to watch the plaintext messages to and from servers from the proprietary clients, and the Python packages scapy and numpy were used for analysis. The syntax was then reimplemented in Python here. CRC RevEng was used for finding the bit length, polynomial, and other characteristics for the Cyclic Redundacy Check the protocol uses, working with a set of captured packets.
Netzob looks like it would have been helpful, had I seen it sooner.
The messages transmitted and received are mainly plaintext mixed with numerical
data as chunks of raw binary. The _checkbytes method of the _Client class
shows the checksumming technique used for most types of messages: a pair of CRC
bytes prepended to the message bytes, with a modular one-byte sum of all bytes
(including the CRC bytes) prepended to that.
This depends on pycrc for calculating CRC values for the transmitted messages.