Documentation

interleave()

Interleaves a sequence of bytes. When encrypting EO data, bytes are "woven" into each other.

Parameters

$data : array<string|int, int>

Reference to the data to interleave.

deinterleave()

Deinterleaves a sequence of bytes. This is the reverse of interleave.

Parameters

$data : array<string|int, int>

Reference to the data to deinterleave.

flipMsb()

Flips the most significant bits of each byte in a sequence of bytes.

Parameters

$data : array<string|int, int>

Reference to the data to flip MSB on.

swapMultiples()

Swaps the order of contiguous bytes in a sequence that are divisible by a given multiple value.

Parameters

$data : array<string|int, int>

Reference to the data to swap bytes in.

$multiple : int

The multiple value.

serverVerificationHash()

This hash function is used by the game client to verify communication with a genuine server during connection initialization.

Parameters

$challenge : int

The challenge value sent by the client. Should be no larger than 11,092,110.

Tags

remarks

The client sends an integer value to the server in the INIT_INIT client packet, where it is referred to as the challenge. The server hashes the value and sends the hash back in the INIT_INIT server packet. The client hashes the value and compares it to the hash sent by the server. If the hashes don't match, the client drops the connection.

warning

Oversized challenges may result in negative hash values, which cannot be represented properly in the EO protocol.

_mod()

Performs a modulus operation, considering negative adjustments.

Parameters

$a : int

The dividend.

$b : int

The divisor.