implement crypto.cc with OpenSSL + fix config loading

I considered reversing the original `vlong` implementation but
OpenSSL is just simpler, more secure, and most importantly, is
already there. I also made it so the key is now stored in a PEM
file (`tibia.pem`) so it can be easily swapped without re-compiling.

  This was the last piece to build and run a working executable,
except that we now need to implement a query manager for the server
to communicate with. I was able to fix a small problem with loading
the config before hitting the problem with the query manager, which
was expected.

  The next task should be getting a query manager up and running
before starting phase two of upgrading and fixing the server itself.

Makefile

@@ -3,8 +3,8 @@ BUILDDIR = build
 OUTPUTEXE = game
 
 CC = g++
-CFLAGS = -m64 -fno-strict-aliasing -pedantic -Wall -Wextra -Wno-unused-parameter -Wno-format-truncation -std=c++11 -DOS_LINUX=1 -DARCH_X64=1
+CFLAGS = -m64 -fno-strict-aliasing -pedantic -Wall -Wextra -Wno-unused-parameter -Wno-format-truncation -std=c++11 -pthread -DOS_LINUX=1 -DARCH_X64=1
-LFLAGS = -Wl,-t
+LFLAGS = -Wl,-t -lcrypto
 
 DEBUG ?= 0
 ifneq ($(DEBUG), 0)
@@ -16,7 +16,7 @@ endif
 HEADERS = $(SRCDIR)/common.hh $(SRCDIR)/communication.hh $(SRCDIR)/config.hh $(SRCDIR)/connections.hh $(SRCDIR)/containers.hh $(SRCDIR)/cr.hh $(SRCDIR)/crypto.hh $(SRCDIR)/enums.hh $(SRCDIR)/houses.hh $(SRCDIR)/info.hh $(SRCDIR)/magic.hh $(SRCDIR)/map.hh $(SRCDIR)/moveuse.hh $(SRCDIR)/objects.hh $(SRCDIR)/operate.hh $(SRCDIR)/query.hh $(SRCDIR)/reader.hh $(SRCDIR)/script.hh $(SRCDIR)/threads.hh $(SRCDIR)/writer.hh
 
 $(BUILDDIR)/$(OUTPUTEXE): $(BUILDDIR)/communication.obj $(BUILDDIR)/config.obj $(BUILDDIR)/connections.obj $(BUILDDIR)/cract.obj $(BUILDDIR)/crcombat.obj $(BUILDDIR)/crmain.obj $(BUILDDIR)/crnonpl.obj $(BUILDDIR)/crplayer.obj $(BUILDDIR)/crskill.obj $(BUILDDIR)/crypto.obj $(BUILDDIR)/houses.obj $(BUILDDIR)/info.obj $(BUILDDIR)/magic.obj $(BUILDDIR)/main.obj $(BUILDDIR)/map.obj $(BUILDDIR)/moveuse.obj $(BUILDDIR)/objects.obj $(BUILDDIR)/operate.obj $(BUILDDIR)/query.obj $(BUILDDIR)/reader.obj $(BUILDDIR)/receiving.obj $(BUILDDIR)/script.obj $(BUILDDIR)/sending.obj $(BUILDDIR)/shm.obj $(BUILDDIR)/strings.obj $(BUILDDIR)/threads.obj $(BUILDDIR)/time.obj $(BUILDDIR)/utils.obj $(BUILDDIR)/writer.obj
-	$(CC) $(CFLAGS) $(LFLAGS) -o $@ $^
+	$(CC) $(CFLAGS) -o $@ $^ $(LFLAGS)
 
 $(BUILDDIR)/communication.obj: $(SRCDIR)/communication.cc $(HEADERS)
 	@mkdir -p $(@D)

reference/types.hh

@@ -1,40 +0,0 @@
-
-struct TDatabasePoolConnection {
-    TDatabaseConnectionPool *DatabaseConnectionPool;
-    TDatabaseConnection *DatabaseConnection;
-    bool TransactionRunning;
-};
-
-struct TDatabaseConnectionPool {
-    int NumberOfConnections;
-    struct TDatabaseSettings DatabaseSettings;
-    struct TDatabaseConnection **DatabaseConnection;
-    bool *DatabaseConnectionFree;
-    struct Semaphore FreeDatabaseConnections;
-    struct Semaphore DatabaseConnectionMutex;
-};
-
-// TODO(fusion): Opaque struct?
-struct TDatabaseConnection {};
-
-struct TPreparedQuery {
-    int Number;
-    char *Query;
-    char *DBTypes;
-    char *CTypes;
-    char *Name;
-};
-
-struct TNameLockOrderData {
-    ulong GamemasterID;
-    char GamemasterName[30];
-    char CharacterName[30];
-    bool OldNameVisible;
-};
-
-struct TNotationOrderData {
-    ulong GamemasterID;
-    char GamemasterName[30];
-    char CharacterName[30];
-    char Comment[200];
-};

src/communication.cc

@@ -23,16 +23,6 @@
 #define MAX_COMMUNICATION_THREADS 1100
 #define COMMUNICATION_THREAD_STACK_SIZE ((int)KB(64))
 
-static const char RSA_PRIME_P[] =
-		"1201758001370723323398753778257470257713354828752713123415294815"
-		"0506251412291888866940292054989907714155267326586216043845592229"
-		"084368540020196135619327879";
-
-static const char RSA_PRIME_Q[] =
-		"1189892136861686835188050824611210139447876026576932541274639840"
-		"5473436969889506919017477758618276066588858607419440134394668095"
-		"105156501566867770737187273";
-
 static int TERMINALVERSION[3] = {770, 770, 770};
 static int TCPSocket;
 static ThreadHandle AcceptorThread;
@@ -1533,7 +1523,9 @@ void InitCommunication(void){
 	AcceptorThreadPID = 0;
 	ActiveConnections = 0;
 	QueryManagerConnectionPool.init();
-	PrivateKey.init(RSA_PRIME_P, RSA_PRIME_Q);
+
+	// TODO(fusion): This is arbitrary, should probably be set in the config.
+	PrivateKey.initFromFile("tibia.pem");
 
 	OpenSocket();
 	if(TCPSocket == -1){

src/config.cc

@@ -106,6 +106,7 @@ void ReadConfig(void){
 	MANAGER_DATABASE.Database[0] = 0;
 
 	char FileName[4096];
+#if 0
 	if(const char *Home = getenv("home")){
 		snprintf(FileName, sizeof(FileName), "%s/.tibia", Home);
 	}else if(const char *Home = getenv("HOME")){
@@ -113,6 +114,9 @@ void ReadConfig(void){
 	}else{
 		snprintf(FileName, sizeof(FileName), ".tibia");
 	}
+#else
+	snprintf(FileName, sizeof(FileName), ".tibia");
+#endif
 
 	if(!FileExists(FileName)){
 		throw "cannot find config-file";
@@ -130,7 +134,7 @@ void ReadConfig(void){
 		}
 
 		char Identifier[MAX_IDENT_LENGTH];
-		strcpy(Identifier, Script.readIdentifier());
+		strcpy(Identifier, Script.getIdentifier());
 		Script.readSymbol('=');
 
 		// TODO(fusion): Ughh... Get rid of all `strcpy`s. A malicious configuration

src/crypto.cc

@@ -1,3 +1,108 @@
 #include "crypto.hh"
 
-// TODO
+#include <openssl/err.h>
+#include <openssl/pem.h>
+
+static void DumpOpenSSLErrors(const char *Where, const char *What){
+	error("OpenSSL error(s) while executing %s at %s:\n", What, Where);
+	ERR_print_errors_cb(
+		[](const char *str, usize len, void *u) -> int {
+			// NOTE(fusion): These error strings already have trailing newlines,
+			// for whatever reason.
+			error("> %s", str);
+			return 1;
+		}, NULL);
+}
+
+// TRSAPrivateKey
+// =============================================================================
+TRSAPrivateKey::TRSAPrivateKey(void){
+	m_RSA = NULL;
+}
+
+TRSAPrivateKey::~TRSAPrivateKey(void){
+	if(m_RSA){
+		RSA_free(m_RSA);
+		m_RSA = NULL;
+	}
+}
+
+void TRSAPrivateKey::initFromFile(const char *FileName){
+	if(m_RSA != NULL){
+		error("TRSAPrivateKey::init: Key already initialized.\n");
+		return;
+	}
+
+	FILE *File = fopen(FileName, "rb");
+	if(File == NULL){
+		error("TRSAPrivateKey::initFromFile: Failed to open \"%s\".\n", FileName);
+		return;
+	}
+
+	m_RSA = PEM_read_RSAPrivateKey(File, NULL, NULL, NULL);
+	fclose(File);
+
+	if(m_RSA == NULL){
+		error("TRSAPrivateKey::initFromFile: Failed to read key from \"%s\".\n", FileName);
+		DumpOpenSSLErrors("TRSAPrivateKey::initFromFile", "PEM_read_RSAPrivateKey");
+	}else if(RSA_size(m_RSA) != 128){
+		error("TRSAPrivateKey::initFromFile: File \"%s\" doesn't contain a 1024-bit key", FileName);
+		RSA_free(m_RSA);
+		m_RSA = NULL;
+	}
+}
+
+void TRSAPrivateKey::decrypt(uint8 *Data){
+	if(m_RSA == NULL){
+		error("TRSAPrivateKey::decrypt: Key not initialized.\n");
+		return;
+	}
+
+	// TODO(fusion): Pass in the length of `Data` for checking.
+	ASSERT(RSA_size(m_RSA) == 128);
+
+	if(RSA_private_decrypt(128, Data, Data, m_RSA, RSA_NO_PADDING) == -1){
+		DumpOpenSSLErrors("TRSAPrivateKey::decrypt", "RSA_private_decrypt");
+	}
+}
+
+// TXTEASymmetricKey
+// =============================================================================
+void TXTEASymmetricKey::init(TReadBuffer *Buffer){
+	m_SymmetricKey[0] = Buffer->readQuad();
+	m_SymmetricKey[1] = Buffer->readQuad();
+	m_SymmetricKey[2] = Buffer->readQuad();
+	m_SymmetricKey[3] = Buffer->readQuad();
+}
+
+void TXTEASymmetricKey::encrypt(uint8 *Data){
+	// TODO(fusion): This assumes both data endpoints have the same byte order.
+	// It's unlikely that there is anything other than little-endian but we
+	// should use a few helping functions to ensure compatibility.
+	uint32 Sum = 0x00000000UL;
+	uint32 Delta = 0x9E3779B9UL;
+	uint32 V0 = *(uint32*)(&Data[0]);
+	uint32 V1 = *(uint32*)(&Data[4]);
+	for(int i = 0; i < 32; i += 1){
+		V0 += (((V1 << 4) ^ (V1 >> 5)) + V1) ^ (Sum + m_SymmetricKey[Sum & 3]);
+		Sum += Delta;
+		V1 += (((V0 << 4) ^ (V0 >> 5)) + V0) ^ (Sum + m_SymmetricKey[(Sum >> 11) & 3]);
+	}
+	*(uint32*)(&Data[0]) = V0;
+	*(uint32*)(&Data[4]) = V1;
+}
+
+void TXTEASymmetricKey::decrypt(uint8 *Data){
+	// TODO(fusion): Same as above.
+	uint32 Sum = 0xC6EF3720UL;
+	uint32 Delta = 0x9E3779B9UL;
+	uint32 V0 = *(uint32*)(&Data[0]);
+	uint32 V1 = *(uint32*)(&Data[4]);
+	for(int i = 0; i < 32; i += 1){
+		V1 -= (((V0 << 4) ^ (V0 >> 5)) + V0) ^ (Sum + m_SymmetricKey[(Sum >> 11) & 3]);
+		Sum -= Delta;
+		V0 -= (((V1 << 4) ^ (V1 >> 5)) + V1) ^ (Sum + m_SymmetricKey[Sum & 3]);
+	}
+	*(uint32*)(&Data[0]) = V0;
+	*(uint32*)(&Data[4]) = V1;
+}

src/crypto.hh

@@ -2,52 +2,20 @@
 #define TIBIA_CRYPTO_HH_ 1
 
 #include "common.hh"
-
+#include <openssl/rsa.h>
-// TODO(fusion): We might want to scrap this implementation and use OpenSSL instead.
-
-struct vlong_flex_unit{
-	uint32 n;
-	uint32 *a;
-	uint32 z;
-};
-
-struct vlong_value: vlong_flex_unit {
-	uint32 share;
-};
-
-struct vlong{
-	vlong_value *value;
-	int negative;
-};
-
-struct vlong_montgomery{
-	vlong R;
-	vlong R1;
-	vlong m;
-	vlong n1;
-	vlong T;
-	vlong k;
-	uint32 N;
-};
 
 struct TRSAPrivateKey{
 	TRSAPrivateKey(void);
 	~TRSAPrivateKey(void);
-	void init(const char *PrimeP, const char *PrimeQ);
+	void initFromFile(const char *FileName);
 	void decrypt(uint8 *Data); // single 128 bytes block
 
 	// DATA
 	// =================
-	vlong m_PrimeP;
+	RSA *m_RSA;
-	vlong m_PrimeQ;
-	vlong m_U;
-	vlong m_DP;
-	vlong m_DQ;
 };
 
 struct TXTEASymmetricKey{
-	TXTEASymmetricKey(void);
-	~TXTEASymmetricKey(void);
 	void init(TReadBuffer *Buffer);
 	void encrypt(uint8 *Data); // single 8 bytes block
 	void decrypt(uint8 *Data); // single 8 bytes block

src/main.cc

@@ -216,7 +216,7 @@ void LoadWorldConfig(void){
 static void InitAll(void){
 	try{
 		ReadConfig();
-		//SetQueryManagerLoginData(1, WorldName);
+		SetQueryManagerLoginData(1, WorldName);
 		LoadWorldConfig();
 		InitSHM(!BeADaemon);
 		LockGame();

src/query.hh

@@ -187,4 +187,6 @@ struct TQueryManagerPoolConnection{
 	TQueryManagerConnection *QueryManagerConnection;
 };
 
+void SetQueryManagerLoginData(int Type, const char *Data);
+
 #endif //TIBIA_QUERY_HH_

tibia.pem

@@ -0,0 +1,15 @@
+-----BEGIN RSA PRIVATE KEY-----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+-----END RSA PRIVATE KEY-----

tools/genpem.go

@@ -0,0 +1,71 @@
+package main
+
+import (
+	"crypto/rsa"
+	"crypto/x509"
+	"encoding/pem"
+	"math/big"
+	"os"
+)
+
+const (
+	P = "1201758001370723323398753778257470257713354828752713123415294815" +
+		"0506251412291888866940292054989907714155267326586216043845592229" +
+		"084368540020196135619327879"
+
+	Q = "1189892136861686835188050824611210139447876026576932541274639840" +
+		"5473436969889506919017477758618276066588858607419440134394668095" +
+		"105156501566867770737187273"
+
+	E = "65537"
+)
+
+func main() {
+	// NOTE(fusion): Generate key from known P, Q, and E. There isn't a helper
+	// function from the standard library so we need to build the private key
+	// ourselves.
+	p, ok := new(big.Int).SetString(P, 10)
+	if !ok || !p.ProbablyPrime(4) {
+		panic("invalid P")
+	}
+
+	q, ok := new(big.Int).SetString(Q, 10)
+	if !ok || !q.ProbablyPrime(4) {
+		panic("invalid Q")
+	}
+
+	e, ok := new(big.Int).SetString(E, 10)
+	if !ok || !e.IsInt64() || !e.ProbablyPrime(4) {
+		panic("invalid E")
+	}
+
+	pMinus1 := new(big.Int).Sub(p, big.NewInt(1))
+	qMinus1 := new(big.Int).Sub(q, big.NewInt(1))
+	gcd := new(big.Int).GCD(nil, nil, pMinus1, qMinus1)
+	phi := new(big.Int).Mul(pMinus1, qMinus1)
+	lambda := new(big.Int).Div(phi, gcd)
+	d := new(big.Int).ModInverse(e, lambda)
+	n := new(big.Int).Mul(p, q)
+
+	privateKey := rsa.PrivateKey{
+		PublicKey: rsa.PublicKey{
+			N: n,
+			E: int(e.Int64()),
+		},
+		D:      d,
+		Primes: []*big.Int{p, q},
+	}
+
+	// NOTE(fusion): `Validate()` will only perform minor sanity checks. To actually
+	// check that the output key is valid use `openssl rsa -in KEY.PEM -check`.
+	if err := privateKey.Validate(); err != nil {
+		panic("invalid private key: " + err.Error())
+	}
+
+	// NOTE(fusion): Dump private key into stdout.
+	block := pem.Block{
+		Type:  "RSA PRIVATE KEY",
+		Bytes: x509.MarshalPKCS1PrivateKey(&privateKey),
+	}
+	pem.Encode(os.Stdout, &block)
+}

tools/makefile.go

@@ -21,11 +21,13 @@ var (
 		"-Wno-unused-parameter",
 		"-Wno-format-truncation",
 		"-std=c++11",
+		"-pthread",
 		"-DOS_LINUX=1",
 		"-DARCH_X64=1",
 	}
 	linkerOptions = []string{
 		"-Wl,-t",
+		"-lcrypto",
 	}
 )
 
@@ -93,7 +95,7 @@ func main() {
 		fmt.Fprintf(&output, " $(BUILDDIR)/%v", object.obj)
 	}
 	fmt.Fprint(&output, "\n")
-	fmt.Fprint(&output, "\t$(CC) $(CFLAGS) $(LFLAGS) -o $@ $^\n\n")
+	fmt.Fprint(&output, "\t$(CC) $(CFLAGS) -o $@ $^ $(LFLAGS)\n\n")
 
 	// OBJECTS
 	for _, object := range objectFiles {