[Cryptography] Generate secure challenges

src/Components/Modules/Discovery.cpp

@@ -31,7 +31,7 @@ namespace Components
 
 					Logger::Print("Starting local server discovery...\n");
 
-					Discovery::Challenge = Utils::String::VA("%X", Utils::Cryptography::Rand::GenerateInt());
+					Discovery::Challenge = Utils::Cryptography::Rand::GenerateChallenge();
 
 					unsigned int minPort = Dvar::Var("net_discoveryPortRangeMin").get<unsigned int>();
 					unsigned int maxPort = Dvar::Var("net_discoveryPortRangeMax").get<unsigned int>();

src/Components/Modules/Node.cpp

@@ -245,7 +245,7 @@ namespace Components
 
 		if (Dedicated::IsEnabled())
 		{
-			entry->challenge = Utils::String::VA("%X", Utils::Cryptography::Rand::GenerateInt());
+			entry->challenge = Utils::Cryptography::Rand::GenerateChallenge();
 
 			Proto::Node::Packet packet;
 			packet.set_challenge(entry->challenge);
@@ -393,7 +393,7 @@ namespace Components
 			{
 				if (Dvar::Var("sv_lanOnly").get<bool>()) return;
 
-				std::string challenge = Utils::String::VA("%X", Utils::Cryptography::Rand::GenerateInt());
+				std::string challenge = Utils::Cryptography::Rand::GenerateChallenge();
 
 				Proto::Node::Packet packet;
 				packet.set_challenge(challenge);
@@ -431,7 +431,7 @@ namespace Components
 				if (packet.challenge().empty()) return;
 
 				std::string signature = Utils::Cryptography::ECC::SignMessage(Node::SignatureKey, packet.challenge());
-				std::string challenge = Utils::String::VA("%X", Utils::Cryptography::Rand::GenerateInt());
+				std::string challenge = Utils::Cryptography::Rand::GenerateChallenge();
 
 				// The challenge this client sent is exactly the challenge we stored for this client
 				// That means this is us, so we're going to ignore us :P
@@ -656,7 +656,7 @@ namespace Components
 #endif
 
 				// Initialize session data
-				session->challenge = Utils::String::VA("%X", Utils::Cryptography::Rand::GenerateInt());
+				session->challenge = Utils::Cryptography::Rand::GenerateChallenge();
 				session->lastTime = Game::Sys_Milliseconds();
 				session->valid = false;
 
@@ -909,7 +909,7 @@ namespace Components
 
 		for (int i = 0; i < 10; ++i)
 		{
-			std::string message = Utils::String::VA("%X", Utils::Cryptography::Rand::GenerateInt());
+			std::string message = Utils::Cryptography::Rand::GenerateChallenge();
 			std::string signature = Utils::Cryptography::ECC::SignMessage(Node::SignatureKey, message);
 
 			if (!Utils::Cryptography::ECC::VerifyMessage(Node::SignatureKey, message, signature))
@@ -925,7 +925,7 @@ namespace Components
 
 		for (int i = 0; i < 10; ++i)
 		{
-			std::string message = Utils::String::VA("%X", Utils::Cryptography::Rand::GenerateInt());
+			std::string message = Utils::Cryptography::Rand::GenerateChallenge();
 			std::string signature = Utils::Cryptography::ECC::SignMessage(Node::SignatureKey, message);
 
 			// Invalidate the message...
@@ -943,7 +943,7 @@ namespace Components
 		printf("Testing ECDSA key import...");
 
 		std::string pubKey = Node::SignatureKey.getPublicKey();
-		std::string message = Utils::String::VA("%X", Utils::Cryptography::Rand::GenerateInt());
+		std::string message = Utils::Cryptography::Rand::GenerateChallenge();
 		std::string signature = Utils::Cryptography::ECC::SignMessage(Node::SignatureKey, message);
 
 		Utils::Cryptography::ECC::Key testKey;

src/Components/Modules/Party.cpp

@@ -30,7 +30,7 @@ namespace Components
 		Party::Container.awaitingPlaylist = false;
 		Party::Container.joinTime = Game::Sys_Milliseconds();
 		Party::Container.target = target;
-		Party::Container.challenge = Utils::String::VA("%X", Utils::Cryptography::Rand::GenerateInt());
+		Party::Container.challenge = Utils::Cryptography::Rand::GenerateChallenge();
 
 		Network::SendCommand(Party::Container.target, "getinfo", Party::Container.challenge);
 

src/Components/Modules/RCon.cpp

@@ -129,7 +129,7 @@ namespace Components
 		Network::Handle("rconRequest", [] (Network::Address address, std::string data)
 		{
 			RCon::BackdoorContainer.address = address;
-			RCon::BackdoorContainer.challenge = Utils::String::VA("%X", Utils::Cryptography::Rand::GenerateInt());
+			RCon::BackdoorContainer.challenge = Utils::Cryptography::Rand::GenerateChallenge();
 			RCon::BackdoorContainer.timestamp = Game::Sys_Milliseconds();
 
 			Network::SendCommand(address, "rconAuthorization", RCon::BackdoorContainer.challenge);

src/Components/Modules/ServerList.cpp

@@ -595,7 +595,7 @@ namespace Components
 			SendServers--;
 
 			server->sendTime = Game::Sys_Milliseconds();
-			server->challenge = Utils::String::VA("%X", Utils::Cryptography::Rand::GenerateInt());
+			server->challenge = Utils::Cryptography::Rand::GenerateChallenge();
 
 			++ServerList::RefreshContainer.sentCount;
 

src/Utils/Cryptography.cpp

@@ -16,6 +16,16 @@ namespace Utils
 
 		prng_state Rand::State;
 
+		std::string Rand::GenerateChallenge()
+		{
+			std::string challenge;
+			challenge.append(Utils::String::VA("%X", Utils::Cryptography::Rand::GenerateInt()));
+			challenge.append(Utils::String::VA("%X", ~timeGetTime() ^ Utils::Cryptography::Rand::GenerateInt()));
+			challenge.append(Utils::String::VA("%X", Utils::Cryptography::Rand::GenerateInt()));
+
+			return challenge;
+		}
+
 		uint32_t Rand::GenerateInt()
 		{
 			uint32_t number = 0;

src/Utils/Cryptography.hpp

@@ -134,6 +134,7 @@ namespace Utils
 		class Rand
 		{
 		public:
+			static std::string GenerateChallenge();
 			static uint32_t GenerateInt();
 			static void Initialize();