messagein.cpp

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/*
 * The ManaPlus Client
 * Copyright (C) 2004-2009 The Mana World Development Team
 * Copyright (C) 2009-2010 The Mana Developers
 * Copyright (C) 2011-2019 The ManaPlus Developers
 * Copyright (C) 2019-2021 Andrei Karas
 *
 * This file is part of The ManaPlus Client.
 *
 * 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
 * the Free Software Foundation; either version 2 of the License, or
 * any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 */
 
#include "net/messagein.h"
 
#include "net/packetcounters.h"
 
#include "utils/cast.h"
#include "utils/stringutils.h"
 
#include "logger.h"
 
#include "debug.h"
 
PRAGMA48(GCC diagnostic push)
PRAGMA48(GCC diagnostic ignored "-Wshadow")
#ifndef SDL_BIG_ENDIAN
#include <SDL_endian.h>
#endif // SDL_BYTEORDER
PRAGMA48(GCC diagnostic pop)
 
#define MAKEWORD(low, high) \
 (CAST_U16((CAST_U8(low)) | \
 (CAST_U16(CAST_U8(high))) << 8))
 
extern int itemIdLen;
extern int packetVersionMain;
extern int packetVersionRe;
extern int packetVersionZero;
 
namespace Net
{
 
MessageIn::MessageIn(const char *const data,
 const unsigned int length) :
 mData(data),
 mLength(length),
 mPos(0),
 mVersion(0),
 mId(0),
 mIgnore(false)
{
 PacketCounters::incInPackets();
}
 
MessageIn::~MessageIn()
{
 if (mLength != 0U)
 {
 if (mPos != mLength && mPos != 2)
 {
 logger->log("Wrong actual or planned inbound packet size!");
 logger->log(" packet id: %u 0x%x",
 CAST_U32(mId),
 CAST_U32(mId));
 logger->log(" planned size: %u", mLength);
 logger->log(" read size: %u", mPos);
 WRONGPACKETSIZE;
 }
 }
 else
 {
 logger->log("Zero packet size: %d", CAST_S32(mId));
 }
}
 
uint16_t MessageIn::readId() const
{
 int16_t value = -1;
 if (mPos + 2 <= mLength)
 {
#if SDL_BYTEORDER == SDL_BIG_ENDIAN
 int16_t swap;
 memcpy(&swap, mData + CAST_SIZE(mPos), sizeof(int16_t));
 value = SDL_Swap16(swap);
#else // SDL_BYTEORDER == SDL_BIG_ENDIAN
 
 memcpy(&value, mData + CAST_SIZE(mPos), sizeof(int16_t));
#endif // SDL_BYTEORDER == SDL_BIG_ENDIAN
 }
 return value;
}
 
unsigned char MessageIn::readUInt8(const char *const str)
{
 unsigned char value = CAST_U8(-1);
 if (mPos < mLength)
 value = CAST_U8(mData[mPos]);
 
 DEBUGLOG2("readUInt8: " + toStringPrint(CAST_U32(value)),
 mPos, str);
 mPos += 1;
 PacketCounters::incInBytes(1);
 return value;
}
 
signed char MessageIn::readInt8(const char *const str)
{
 signed char value = CAST_S8(-1);
 if (mPos < mLength)
 value = CAST_S8(mData[mPos]);
 
 DEBUGLOG2("readInt8: " + toStringPrint(CAST_U32(
 CAST_U8(value))),
 mPos, str);
 mPos += 1;
 PacketCounters::incInBytes(1);
 return value;
}
 
int16_t MessageIn::readInt16(const char *const str)
{
 int16_t value = -1;
 if (mPos + 2 <= mLength)
 {
#if SDL_BYTEORDER == SDL_BIG_ENDIAN
 int16_t swap;
 memcpy(&swap, mData + CAST_SIZE(mPos), sizeof(int16_t));
 value = SDL_Swap16(swap);
#else // SDL_BYTEORDER == SDL_BIG_ENDIAN
 
 memcpy(&value, mData + CAST_SIZE(mPos), sizeof(int16_t));
#endif // SDL_BYTEORDER == SDL_BIG_ENDIAN
 }
 DEBUGLOG2("readInt16: " + toStringPrint(CAST_U32(
 CAST_U16(value))),
 mPos, str);
 mPos += 2;
 PacketCounters::incInBytes(2);
 return value;
}
 
uint16_t MessageIn::readUInt16(const char *const str)
{
 uint16_t value = 0xffU;
 if (mPos + 2 <= mLength)
 {
#if SDL_BYTEORDER == SDL_BIG_ENDIAN
 uint16_t swap;
 memcpy(&swap, mData + CAST_SIZE(mPos), sizeof(uint16_t));
 value = SDL_Swap16(swap);
#else // SDL_BYTEORDER == SDL_BIG_ENDIAN
 
 memcpy(&value, mData + CAST_SIZE(mPos), sizeof(uint16_t));
#endif // SDL_BYTEORDER == SDL_BIG_ENDIAN
 }
 DEBUGLOG2("readUInt16: " + toStringPrint(CAST_U32(
 CAST_U16(value))),
 mPos, str);
 mPos += 2;
 PacketCounters::incInBytes(2);
 return value;
}
 
int32_t MessageIn::readInt32(const char *const str)
{
 int32_t value = -1;
 if (mPos + 4 <= mLength)
 {
#if SDL_BYTEORDER == SDL_BIG_ENDIAN
 int32_t swap;
 memcpy(&swap, mData + CAST_SIZE(mPos), sizeof(int32_t));
 value = SDL_Swap32(swap);
#else // SDL_BYTEORDER == SDL_BIG_ENDIAN
 
 memcpy(&value, mData + CAST_SIZE(mPos), sizeof(int32_t));
#endif // SDL_BYTEORDER == SDL_BIG_ENDIAN
 }
 DEBUGLOG2("readInt32: " + toStringPrint(CAST_S32(value)),
 mPos, str);
 mPos += 4;
 PacketCounters::incInBytes(4);
 return value;
}
 
uint32_t MessageIn::readUInt32(const char *const str)
{
 uint32_t value = 0;
 if (mPos + 4 <= mLength)
 {
#if SDL_BYTEORDER == SDL_BIG_ENDIAN
 uint32_t swap;
 memcpy(&swap, mData + CAST_SIZE(mPos), sizeof(int32_t));
 value = SDL_Swap32(swap);
#else // SDL_BYTEORDER == SDL_BIG_ENDIAN
 
 memcpy(&value, mData + CAST_SIZE(mPos), sizeof(int32_t));
#endif // SDL_BYTEORDER == SDL_BIG_ENDIAN
 }
 DEBUGLOG2("readInt32: " + toStringPrint(CAST_U32(value)),
 mPos, str);
 mPos += 4;
 PacketCounters::incInBytes(4);
 return value;
}
 
int MessageIn::readItemId(const char *const str)
{
 if (itemIdLen == 2)
 return readInt16(str);
 return readInt32(str);
}
 
BeingId MessageIn::readBeingId(const char *const str)
{
 return fromInt(readUInt32(str), BeingId);
}
 
int64_t MessageIn::readInt64(const char *const str)
{
 int64_t value = -1;
 if (mPos + 8 <= mLength)
 {
#if SDL_BYTEORDER == SDL_BIG_ENDIAN
 int64_t swap;
 memcpy(&swap, mData + CAST_SIZE(mPos), sizeof(int64_t));
 value = SDL_Swap64(swap);
#else // SDL_BYTEORDER == SDL_BIG_ENDIAN
 
 memcpy(&value, mData + CAST_SIZE(mPos), sizeof(int64_t));
#endif // SDL_BYTEORDER == SDL_BIG_ENDIAN
 }
 DEBUGLOG2("readInt64: " + toStringPrint(CAST_U32(value)),
 mPos, str);
 mPos += 8;
 PacketCounters::incInBytes(8);
 return value;
}
 
float MessageIn::readFloat(const char *const str)
{
 float value = 0;
 if (mPos + 4 <= mLength)
 {
 memcpy(&value, mData + CAST_SIZE(mPos), sizeof(float));
 }
#ifdef ENABLEDEBUGLOG
 std::string text = strprintf("readFloat: %f", value);
 DEBUGLOG2(str, mPos, text.c_str());
#endif
 mPos += 4;
 PacketCounters::incInBytes(4);
 return value;
}
 
uint8_t MessageIn::fromServerDirection(const uint8_t serverDir)
{
 // Translate from eAthena format
 switch (serverDir)
 {
 case 0:
 return 1;
 case 1:
 return 3;
 case 2:
 return 2;
 case 3:
 return 6;
 case 4:
 return 4;
 case 5:
 return 12;
 case 6:
 return 8;
 case 7:
 return 9;
 case 8:
 return 8;
 default:
 logger->log("incorrect direction: %d",
 CAST_S32(serverDir));
 return 0;
 }
}
 
void MessageIn::readCoordinates(uint16_t &restrict x,
 uint16_t &restrict y,
 uint8_t &restrict direction,
 const char *const str)
{
 if (mPos + 3 <= mLength)
 {
 const char *const data = mData + CAST_SIZE(mPos);
 uint16_t temp = MAKEWORD(data[1] & 0x00c0, data[0] & 0x00ff);
 x = CAST_U16(temp >> 6);
 temp = MAKEWORD(data[2] & 0x00f0, data[1] & 0x003f);
 y = CAST_U16(temp >> 4);
 
 const uint8_t serverDir = CAST_U8(data[2] & 0x000f);
 direction = fromServerDirection(serverDir);
 
 DEBUGLOG2(std::string("readCoordinates: ").append(toString(
 CAST_S32(x))).append(",").append(toString(
 CAST_S32(y))).append(",").append(toString(
 CAST_S32(serverDir))), mPos, str);
 }
 else
 {
 x = 0;
 y = 0;
 direction = 0;
 logger->log("error: wrong readCoordinates packet");
 }
 mPos += 3;
 PacketCounters::incInBytes(3);
}
 
void MessageIn::readCoordinatePair(uint16_t &restrict srcX,
 uint16_t &restrict srcY,
 uint16_t &restrict dstX,
 uint16_t &restrict dstY,
 const char *const str)
{
 if (mPos + 5 <= mLength)
 {
 const char *const data = mData + CAST_SIZE(mPos);
 uint16_t temp = MAKEWORD(data[3], data[2] & 0x000f);
 dstX = CAST_U16(temp >> 2);
 
 dstY = MAKEWORD(data[4], data[3] & 0x0003);
 
 temp = MAKEWORD(data[1], data[0]);
 srcX = CAST_U16(temp >> 6);
 
 temp = MAKEWORD(data[2], data[1] & 0x003f);
 srcY = CAST_U16(temp >> 4);
 
 DEBUGLOG2(std::string("readCoordinatePair: ").append(toString(
 CAST_S32(srcX))).append(",").append(toString(
 CAST_S32(srcY))).append(" ").append(toString(
 CAST_S32(dstX))).append(",").append(toString(
 CAST_S32(dstY))), mPos, str);
 }
 else
 {
 srcX = 0;
 srcY = 0;
 dstX = 0;
 dstY = 0;
 logger->log("error: wrong readCoordinatePair packet");
 }
 mPos += 5;
 PacketCounters::incInBytes(5);
}
 
void MessageIn::skip(const unsigned int length, const char *const str)
{
 DEBUGLOG2("skip: " + toString(CAST_S32(length)), mPos, str);
 mPos += length;
 PacketCounters::incInBytes(length);
}
 
void MessageIn::skipToEnd(const char *const str)
{
 const int diff = CAST_S32(mLength - mPos);
 if (diff != 0)
 {
 DEBUGLOG2("skip: " + toString(diff), mPos, str);
 mPos = mLength;
 PacketCounters::incInBytes(diff);
 }
}
 
std::string MessageIn::readString(int length, const char *const dstr)
{
 // Get string length
 if (length < 0)
 length = readInt16("len");
 
 // Make sure the string isn't erroneous
 if (length < 0 || mPos + length > mLength)
 {
 DEBUGLOG2("readString error", mPos, dstr);
 mPos = mLength + 1;
 return "";
 }
 
 // Read the string
 const char *const stringBeg = mData + CAST_SIZE(mPos);
 const char *const stringEnd
 = static_cast<const char *>(memchr(stringBeg, '\0', length));
 
 const std::string str(stringBeg, stringEnd != nullptr
 ? stringEnd - stringBeg : CAST_SIZE(length));
 DEBUGLOG2("readString: " + str, mPos, dstr);
 mPos += length;
 PacketCounters::incInBytes(length);
 return str;
}
 
std::string MessageIn::readRawString(int length, const char *const dstr)
{
 // Get string length
 if (length < 0)
 length = readInt16("len");
 
 // Make sure the string isn't erroneous
 if (length < 0 || mPos + length > mLength)
 {
 mPos = mLength + 1;
 return "";
 }
 
 // Read the string
 const char *const stringBeg = mData + CAST_SIZE(mPos);
 const char *const stringEnd
 = static_cast<const char *>(memchr(stringBeg, '\0', length));
 std::string str(stringBeg, stringEnd != nullptr
 ? stringEnd - stringBeg : CAST_SIZE(length));
 
 DEBUGLOG2("readString: " + str, mPos, dstr);
 
 if (stringEnd != nullptr)
 {
 const size_t len2 = CAST_SIZE(length)
 - (stringEnd - stringBeg) - 1;
 const char *const stringBeg2 = stringEnd + 1;
 const char *const stringEnd2
 = static_cast<const char *>(memchr(stringBeg2, '\0', len2));
 const std::string hiddenPart = std::string(stringBeg2,
 stringEnd2 != nullptr ? stringEnd2 - stringBeg2 : len2);
 if (hiddenPart.length() > 0)
 {
 DEBUGLOG2("readString2: " + hiddenPart, mPos, dstr);
 return str.append("|").append(hiddenPart);
 }
 }
 mPos += length;
 PacketCounters::incInBytes(length);
 
 return str;
}
 
unsigned char *MessageIn::readBytes(int length, const char *const dstr)
{
 // Get string length
 if (length < 0)
 length = readInt16("len");
 
 // Make sure the string isn't erroneous
 if (length < 0 || mPos + length > mLength)
 {
 DEBUGLOG2("readBytesString error", mPos, dstr);
 mPos = mLength + 1;
 return nullptr;
 }
 
 unsigned char *const buf
 = new unsigned char[CAST_SIZE(length + 2)];
 
 memcpy(buf, mData + CAST_SIZE(mPos), length);
 buf[length] = 0;
 buf[length + 1] = 0;
 mPos += length;
 
#ifdef ENABLEDEBUGLOG
 if (!mIgnore)
 {
 std::string str;
 for (int f = 0; f < length; f ++)
 str.append(strprintf("%02x", CAST_U32(buf[f])));
 str += " ";
 for (int f = 0; f < length; f ++)
 {
 if (buf[f] != 0U)
 str.append(strprintf("%c", buf[f]));
 else
 str.append("_");
 }
 if (dstr != nullptr)
 logger->dlog(dstr);
 logger->dlog("ReadBytes: " + str);
 }
#endif // ENABLEDEBUGLOG
 
 PacketCounters::incInBytes(length);
 return buf;
}
 
int MessageIn::getVersionMain() const noexcept2
{
 if (packetVersionMain >= mVersion)
 return mVersion;
 return 0;
}
 
int MessageIn::getVersionRe() const noexcept2
{
 if (packetVersionRe >= mVersion)
 return mVersion;
 return 0;
}
 
int MessageIn::getVersionZero() const noexcept2
{
 if (packetVersionZero >= mVersion)
 return mVersion;
 return 0;
}
 
} // namespace Net