fix walking issue in 781 protocol

This commit is contained in:
ErikasKontenis 2019-11-11 19:17:21 +02:00
parent ba1409dbe6
commit 5535e50562
4 changed files with 70 additions and 29 deletions

View File

@ -22,7 +22,6 @@
#include "protocol.h"
#include "outputmessage.h"
#include "rsa.h"
#include "xtea.h"
extern RSA g_RSA;
@ -62,27 +61,73 @@ OutputMessage_ptr Protocol::getOutputBuffer(int32_t size)
void Protocol::XTEA_encrypt(OutputMessage& msg) const
{
const uint32_t delta = 0x61C88647;
// The message must be a multiple of 8
size_t paddingBytes = msg.getLength() % 8u;
size_t paddingBytes = msg.getLength() % 8;
if (paddingBytes != 0) {
msg.addPaddingBytes(8 - paddingBytes);
}
uint8_t* buffer = msg.getOutputBuffer();
xtea::encrypt(buffer, msg.getLength(), key);
const size_t messageLength = msg.getLength();
size_t readPos = 0;
const uint32_t k[] = { key[0], key[1], key[2], key[3] };
while (readPos < messageLength) {
uint32_t v0;
memcpy(&v0, buffer + readPos, 4);
uint32_t v1;
memcpy(&v1, buffer + readPos + 4, 4);
uint32_t sum = 0;
for (int32_t i = 32; --i >= 0;) {
v0 += ((v1 << 4 ^ v1 >> 5) + v1) ^ (sum + k[sum & 3]);
sum -= delta;
v1 += ((v0 << 4 ^ v0 >> 5) + v0) ^ (sum + k[(sum >> 11) & 3]);
}
memcpy(buffer + readPos, &v0, 4);
readPos += 4;
memcpy(buffer + readPos, &v1, 4);
readPos += 4;
}
}
bool Protocol::XTEA_decrypt(NetworkMessage& msg) const
{
if (((msg.getLength() - 6) & 7) != 0) {
if (((msg.getLength() - 2) & 7) != 0) {
return false;
}
uint8_t* buffer = msg.getBuffer() + msg.getBufferPosition();
xtea::decrypt(buffer, msg.getLength() - 6, key);
const uint32_t delta = 0x61C88647;
uint16_t innerLength = msg.get<uint16_t>();
if (innerLength + 8 > msg.getLength()) {
uint8_t* buffer = msg.getBuffer() + msg.getBufferPosition();
const size_t messageLength = (msg.getLength() - 2);
size_t readPos = 0;
const uint32_t k[] = { key[0], key[1], key[2], key[3] };
while (readPos < messageLength) {
uint32_t v0;
memcpy(&v0, buffer + readPos, 4);
uint32_t v1;
memcpy(&v1, buffer + readPos + 4, 4);
uint32_t sum = 0xC6EF3720;
for (int32_t i = 32; --i >= 0;) {
v1 -= ((v0 << 4 ^ v0 >> 5) + v0) ^ (sum + k[(sum >> 11) & 3]);
sum += delta;
v0 -= ((v1 << 4 ^ v1 >> 5) + v1) ^ (sum + k[sum & 3]);
}
memcpy(buffer + readPos, &v0, 4);
readPos += 4;
memcpy(buffer + readPos, &v1, 4);
readPos += 4;
}
int innerLength = msg.get<uint16_t>();
if (innerLength > msg.getLength() - 4) {
return false;
}
@ -92,7 +137,7 @@ bool Protocol::XTEA_decrypt(NetworkMessage& msg) const
bool Protocol::RSA_decrypt(NetworkMessage& msg)
{
if ((msg.getLength() - msg.getBufferPosition()) < 128) {
if ((msg.getLength() - msg.getBufferPosition()) != 128) {
return false;
}

View File

@ -1,6 +1,6 @@
/**
* Tibia GIMUD Server - a free and open-source MMORPG server emulator
* Copyright (C) 2019 Sabrehaven and Mark Samman <mark.samman@gmail.com>
* The Forgotten Server - a free and open-source MMORPG server emulator
* Copyright (C) 2016 Mark Samman <mark.samman@gmail.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
@ -21,12 +21,11 @@
#define FS_PROTOCOL_H_D71405071ACF4137A4B1203899DE80E1
#include "connection.h"
#include "xtea.h"
class Protocol : public std::enable_shared_from_this<Protocol>
{
public:
explicit Protocol(Connection_ptr connection) : connection(connection) {}
explicit Protocol(Connection_ptr connection) : connection(connection), key(), encryptionEnabled(false), rawMessages(false) {}
virtual ~Protocol() = default;
// non-copyable
@ -72,10 +71,12 @@ protected:
void enableXTEAEncryption() {
encryptionEnabled = true;
}
void setXTEAKey(xtea::key key) {
this->key = std::move(key);
void setXTEAKey(const uint32_t* key) {
memcpy(this->key, key, sizeof(*key) * 4);
}
void XTEA_encrypt(OutputMessage& msg) const;
bool XTEA_decrypt(NetworkMessage& msg) const;
static bool RSA_decrypt(NetworkMessage& msg);
void setRawMessages(bool value) {
@ -83,19 +84,14 @@ protected:
}
virtual void release() {}
private:
void XTEA_encrypt(OutputMessage& msg) const;
bool XTEA_decrypt(NetworkMessage& msg) const;
friend class Connection;
OutputMessage_ptr outputBuffer;
private:
const ConnectionWeak_ptr connection;
xtea::key key;
bool encryptionEnabled = false;
bool rawMessages = false;
uint32_t key[4];
bool encryptionEnabled;
bool rawMessages;
};
#endif

View File

@ -247,13 +247,13 @@ void ProtocolGame::onRecvFirstMessage(NetworkMessage& msg)
return;
}
xtea::key key;
uint32_t key[4];
key[0] = msg.get<uint32_t>();
key[1] = msg.get<uint32_t>();
key[2] = msg.get<uint32_t>();
key[3] = msg.get<uint32_t>();
enableXTEAEncryption();
setXTEAKey(std::move(key));
setXTEAKey(key);
if (operatingSystem >= CLIENTOS_OTCLIENT_LINUX) {
NetworkMessage opcodeMessage;

View File

@ -128,13 +128,13 @@ void ProtocolLogin::onRecvFirstMessage(NetworkMessage& msg)
return;
}
xtea::key key;
uint32_t key[4];
key[0] = msg.get<uint32_t>();
key[1] = msg.get<uint32_t>();
key[2] = msg.get<uint32_t>();
key[3] = msg.get<uint32_t>();
enableXTEAEncryption();
setXTEAKey(std::move(key));
setXTEAKey(key);
if (version < CLIENT_VERSION_MIN || version > CLIENT_VERSION_MAX) {
std::ostringstream ss;