Interface

Interface for encoding/decoding modules

For the encoding modules on the upstream side

Init()

• Called on each of the encoding modules
• Performs any initialization actions that are necessary.
• Expected to be very basic.

Register()

• Called on each of the encoding modules at initialization
• Provides encoding decision module information it needs to decide
• Returns:
  • Minimum size - likely to be 1 byte for URLs and ~4-30k for an image
  • Maximum size - likely to be 1000 bytes for URLs and MBs for an image

Send()

• Returns errors
• takes in a buffer that is to be encoded
• takes in size of data to be encoded
• Sends all the data that's requested, either in one or many outbound packets (many URLs for instance)

For the encoding modules on the downstream side

Receive()

• Returns errors
• Takes a buffer that is to be decoded
• Takes in size of data to be decoded

For the decision part of HTPT on the upstream side

ReceiveCallback()

• Takes a list of decoded data
• passes it up to Tor

GetSequenceAndIncrement()

• Returns sequence number and increments
• Used by the various encode/decode modules that implement Send()

For the decision part of HTPT on the downstream side

SendData()

• Sends data
• Called by the various encode/decode modules