Network services speak a certain language, this language is called protocol. When we started deploying honeypots, you could trap worms just by opening a single port, and wait for them to connect and send you an url where you could download a copy of the worm. The service getting attacked was the backdoor of the bagle mailworm, and it did not require and interaction. Later on, the exploitations of real services got more complex, and you had to reply something to the worm to fool him. Nowadays worms use API to access services, before sending their payload. To allow easy adjustments to the procotol, dionaea implements the protocols in python. There is a glue between the network layer which is done in the c programming language and the embedded python scripting language, which allows using the non-blocking connections in python. This has some benefits, for example we can use non-blocking tls connections in python, and we even get rate limiting on them (if required), where pythons own io does not offer such things. On the other hand, it is much more comfortable to implement protocols in python than doing the same in c.

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