Start repo, claude & kimi still vibing tho

2026-02-14 17:04:21 -07:00
commit f5b8aeb39d
54 changed files with 9466 additions and 0 deletions
--- a/lib/odinsea/net/cipher/ig_cipher.ex
+++ b/lib/odinsea/net/cipher/ig_cipher.ex
@@ -0,0 +1,92 @@
+defmodule Odinsea.Net.Cipher.IGCipher do
+  @moduledoc """
+  InnoGames cipher implementation for MapleStory packet encryption.
+  Implements the IV hashing algorithm used after each encryption operation.
+
+  Ported from: src/handling/netty/cipher/IGCipher.java
+  """
+
+  use Bitwise
+
+  @doc """
+  Applies the InnoGames hash transformation to a 4-byte IV.
+  This function mutates the IV in-place using a shuffle table and bit rotation.
+
+  ## Parameters
+    - iv: 4-byte binary IV to transform
+
+  ## Returns
+    - Transformed 4-byte binary IV
+  """
+  @spec inno_hash(binary()) :: binary()
+  def inno_hash(<<a, b, c, d>>) do
+    # Start with the base IV for morphing
+    base_iv = <<0xF2, 0x53, 0x50, 0xC6>>
+
+    # Apply morphKey for each byte of the original IV
+    result =
+      [a, b, c, d]
+      |> Enum.reduce(base_iv, fn value, acc ->
+        morph_key(acc, value)
+      end)
+
+    result
+  end
+
+  # Morph a 4-byte key using a single input byte value
+  @spec morph_key(binary(), byte()) :: binary()
+  defp morph_key(<<k0, k1, k2, k3>>, value) do
+    input = value &&& 0xFF
+    table = shuffle_byte(input)
+
+    # Apply the transformation operations
+    new_k0 = k0 + shuffle_byte(k1) - input
+    new_k1 = k1 - bxor(k2, table)
+    new_k2 = bxor(k2, shuffle_byte(k3) + input)
+    new_k3 = k3 - (k0 - table)
+
+    # Combine into 32-bit value (little-endian)
+    val =
+      (new_k0 &&& 0xFF) |||
+        ((new_k1 <<< 8) &&& 0xFF00) |||
+        ((new_k2 <<< 16) &&& 0xFF0000) |||
+        ((new_k3 <<< 24) &&& 0xFF000000)
+
+    # Rotate left by 3 bits
+    rotated = ((val <<< 3) ||| (val >>> 29)) &&& 0xFFFFFFFF
+
+    # Extract bytes (little-endian)
+    <<
+      rotated &&& 0xFF,
+      (rotated >>> 8) &&& 0xFF,
+      (rotated >>> 16) &&& 0xFF,
+      (rotated >>> 24) &&& 0xFF
+    >>
+  end
+
+  # Lookup a byte in the shuffle table
+  @spec shuffle_byte(integer()) :: integer()
+  defp shuffle_byte(index) do
+    elem(@shuffle_table, index &&& 0xFF)
+  end
+
+  # Shuffle table - 256 bytes used for IV transformation
+  @shuffle_table {
+    0xEC, 0x3F, 0x77, 0xA4, 0x45, 0xD0, 0x71, 0xBF, 0xB7, 0x98, 0x20, 0xFC, 0x4B, 0xE9, 0xB3, 0xE1,
+    0x5C, 0x22, 0xF7, 0x0C, 0x44, 0x1B, 0x81, 0xBD, 0x63, 0x8D, 0xD4, 0xC3, 0xF2, 0x10, 0x19, 0xE0,
+    0xFB, 0xA1, 0x6E, 0x66, 0xEA, 0xAE, 0xD6, 0xCE, 0x06, 0x18, 0x4E, 0xEB, 0x78, 0x95, 0xDB, 0xBA,
+    0xB6, 0x42, 0x7A, 0x2A, 0x83, 0x0B, 0x54, 0x67, 0x6D, 0xE8, 0x65, 0xE7, 0x2F, 0x07, 0xF3, 0xAA,
+    0x27, 0x7B, 0x85, 0xB0, 0x26, 0xFD, 0x8B, 0xA9, 0xFA, 0xBE, 0xA8, 0xD7, 0xCB, 0xCC, 0x92, 0xDA,
+    0xF9, 0x93, 0x60, 0x2D, 0xDD, 0xD2, 0xA2, 0x9B, 0x39, 0x5F, 0x82, 0x21, 0x4C, 0x69, 0xF8, 0x31,
+    0x87, 0xEE, 0x8E, 0xAD, 0x8C, 0x6A, 0xBC, 0xB5, 0x6B, 0x59, 0x13, 0xF1, 0x04, 0x00, 0xF6, 0x5A,
+    0x35, 0x79, 0x48, 0x8F, 0x15, 0xCD, 0x97, 0x57, 0x12, 0x3E, 0x37, 0xFF, 0x9D, 0x4F, 0x51, 0xF5,
+    0xA3, 0x70, 0xBB, 0x14, 0x75, 0xC2, 0xB8, 0x72, 0xC0, 0xED, 0x7D, 0x68, 0xC9, 0x2E, 0x0D, 0x62,
+    0x46, 0x17, 0x11, 0x4D, 0x6C, 0xC4, 0x7E, 0x53, 0xC1, 0x25, 0xC7, 0x9A, 0x1C, 0x88, 0x58, 0x2C,
+    0x89, 0xDC, 0x02, 0x64, 0x40, 0x01, 0x5D, 0x38, 0xA5, 0xE2, 0xAF, 0x55, 0xD5, 0xEF, 0x1A, 0x7C,
+    0xA7, 0x5B, 0xA6, 0x6F, 0x86, 0x9F, 0x73, 0xE6, 0x0A, 0xDE, 0x2B, 0x99, 0x4A, 0x47, 0x9C, 0xDF,
+    0x09, 0x76, 0x9E, 0x30, 0x0E, 0xE4, 0xB2, 0x94, 0xA0, 0x3B, 0x34, 0x1D, 0x28, 0x0F, 0x36, 0xE3,
+    0x23, 0xB4, 0x03, 0xD8, 0x90, 0xC8, 0x3C, 0xFE, 0x5E, 0x32, 0x24, 0x50, 0x1F, 0x3A, 0x43, 0x8A,
+    0x96, 0x41, 0x74, 0xAC, 0x52, 0x33, 0xF0, 0xD9, 0x29, 0x80, 0xB1, 0x16, 0xD3, 0xAB, 0x91, 0xB9,
+    0x84, 0x7F, 0x61, 0x1E, 0xCF, 0xC5, 0xD1, 0x56, 0x3D, 0xCA, 0xF4, 0x05, 0xC6, 0xE5, 0x08, 0x49
+  }
+end