Beaconizer-protocols

Beaconizers connect to the master server on port 48813 and to other BeaconServer instances on ports ranging from 48812 to 48913. They use the common Network protocol.

Commands, client to server

All BeaconServer modes accept the same messages from clients. Clients have a state, stored in BeaconServerClientData.state, which is BCS_NOT_CONNECTED for newly connected clients.

BMSG_C2S_CONNECT

bits(32) exe_crc_old
optional, if exe_crc_old is 0:
  packint(1) protocol_version
  bits(32) exe_crc
string user_name
string computer_name
bits(1) is_sentry

If the client is in state BCS_ERROR_NONLOCAL_IP then this message is ignored, other than recording the names and version. If the client is in any other state which is not BCS_NOT_CONNECTED then the state is set to BCS_ERROR_PROTOCOL and this message is ignored. Otherwise, when the state is BCS_NOT_CONNECTED:

If exe_crc_old is not 0, then it is the exe_crc value. Otherwise, the optional version is used.

If exe_crc does not match the crc of the executable for the server receiving the message, then the client will be moved to state BCS_ERROR_PROTOCOL in production mode, and sent a BMSG_S2C_CONNECT_REPLY with good set to 0 in development mode, and the client is moved to state BCS_NEEDS_MORE_EXE_DATA.

If exe_crc does match, then the client will be accepted. If is_sentry is true then the client type will be set to BCT_SENTRY and the state to BCS_SENTRY. If is_sentry is false then the client type will be set to BCT_WORKER and the client state to BCS_CONNECTED.

BMSG_S2C_CONNECT_REPLY is sent with good set to 1.

BMSG_C2S_SERVER_CONNECT

packint(1) protocol_version
bits(32) exe_crc
string user_name
string computer_name
packint(1) server_port
when protocol_version is at least 1:
  bits(1) is_request_server

If the client is in state BCS_ERROR_NONLOCAL_IP then this message is ignored, other than recording the names and version. If the client is in any other state which is not BCS_NOT_CONNECTED then the state is set to BCS_ERROR_PROTOCOL and this message is ignored. Otherwise, when the state is BCS_NOT_CONNECTED:

The crc match is checked against this binary and printed on the console but otherwise ignored.

The other fields are recorded for later use.

The client state is moved to BCS_SERVER and BMSG_S2C_CONNECT_REPLY is sent with good set to 1.

Commands, server to client

BMSG_S2C_CONNECT_REPLY

bits(1) good
when good is 1:
  bits(32) client_uid
  string server_uid
optional, when good is 0:
  packint(1) size
  bits(size * 8) data

When good is 1, the connection is being accepted. Otherwise, this indicates that the client should get a new executable, and optionally contains the data.