using System; using System.Net; using NetcodeIO.NET.Utils; namespace NetcodeIO.NET { internal class EncryptionManager { internal struct encryptionMapEntry { public double ExpireTime; public double LastAccessTime; public EndPoint Address; public byte[] SendKey; public byte[] ReceiveKey; public void Reset() { ExpireTime = -1.0; LastAccessTime = -1000.0; Address = null; Array.Clear(SendKey, 0, SendKey.Length); Array.Clear(ReceiveKey, 0, ReceiveKey.Length); } } internal int numEncryptionMappings; internal encryptionMapEntry[] encryptionMappings; public EncryptionManager( int maxClients ) { encryptionMappings = new encryptionMapEntry[maxClients * 4]; for (int i = 0; i < encryptionMappings.Length; i++) { encryptionMappings[i].SendKey = new byte[32]; encryptionMappings[i].ReceiveKey = new byte[32]; } Reset(); } public void Reset() { numEncryptionMappings = 0; for (int i = 0; i < encryptionMappings.Length; i++) { encryptionMappings[i].Reset(); } } public bool AddEncryptionMapping(EndPoint address, byte[] sendKey, byte[] receiveKey, double time, double expireTime) { for (int i = 0; i < numEncryptionMappings; i++) { if ( MiscUtils.AddressEqual( encryptionMappings[i].Address, address ) && encryptionMappings[i].LastAccessTime + Defines.NETCODE_TIMEOUT_SECONDS >= time) { encryptionMappings[i].ExpireTime = expireTime; encryptionMappings[i].LastAccessTime = time; Buffer.BlockCopy(sendKey, 0, encryptionMappings[i].SendKey, 0, 32); Buffer.BlockCopy(receiveKey, 0, encryptionMappings[i].ReceiveKey, 0, 32); return true; } } for (int i = 0; i < encryptionMappings.Length; i++) { if (encryptionMappings[i].LastAccessTime + Defines.NETCODE_TIMEOUT_SECONDS < time || (encryptionMappings[i].ExpireTime >= 0.0 && encryptionMappings[i].ExpireTime < time)) { encryptionMappings[i].Address = address; encryptionMappings[i].ExpireTime = expireTime; encryptionMappings[i].LastAccessTime = time; Buffer.BlockCopy(sendKey, 0, encryptionMappings[i].SendKey, 0, 32); Buffer.BlockCopy(receiveKey, 0, encryptionMappings[i].ReceiveKey, 0, 32); if (i + 1 > numEncryptionMappings) numEncryptionMappings = i + 1; return true; } } return false; } public bool RemoveEncryptionMapping(EndPoint address, double time) { for (int i = 0; i < numEncryptionMappings; i++) { if (MiscUtils.AddressEqual(encryptionMappings[i].Address, address)) { encryptionMappings[i].Reset(); if (i + 1 == numEncryptionMappings) { int index = i - 1; while (index >= 0) { if (encryptionMappings[i].LastAccessTime + Defines.NETCODE_TIMEOUT_SECONDS >= time && (encryptionMappings[i].ExpireTime < 0 || encryptionMappings[i].ExpireTime > time)) break; index--; } numEncryptionMappings = index + 1; } return true; } } return false; } public byte[] GetSendKey(int idx) { return encryptionMappings[idx].SendKey; } public byte[] GetReceiveKey(int idx) { return encryptionMappings[idx].ReceiveKey; } public bool Touch(int index, EndPoint address, double time) { if (index < 0 || index >= numEncryptionMappings) throw new IndexOutOfRangeException(); if (!MiscUtils.AddressEqual(encryptionMappings[index].Address, address)) return false; encryptionMappings[index].LastAccessTime = time; encryptionMappings[index].ExpireTime = time + Defines.NETCODE_TIMEOUT_SECONDS; return true; } public void SetExpireTime(int index, double expireTime) { if (index < 0 || index >= numEncryptionMappings) throw new IndexOutOfRangeException(); encryptionMappings[index].ExpireTime = expireTime; } public int FindEncryptionMapping(EndPoint address, double time) { for (int i = 0; i < numEncryptionMappings; i++) { if (MiscUtils.AddressEqual(encryptionMappings[i].Address, address) && encryptionMappings[i].LastAccessTime + Defines.NETCODE_TIMEOUT_SECONDS >= time && (encryptionMappings[i].ExpireTime < 0.0 || encryptionMappings[i].ExpireTime >= time)) { encryptionMappings[i].LastAccessTime = time; return i; } } return -1; } } }