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Feature: encrypt the connection between game server and client

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Rubidium
2024-03-14 21:36:28 +01:00
committed by rubidium42
parent d26629c15b
commit 1cf8799810
12 changed files with 143 additions and 33 deletions
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32
src/network/core/packet.cpp
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@@ -48,7 +48,14 @@ Packet::Packet(NetworkSocketHandler *cs, size_t limit, size_t initial_read_size)
Packet::Packet(NetworkSocketHandler *cs, PacketType type, size_t limit) : pos(0), limit(limit), cs(cs)
{
/* Allocate space for the the size so we can write that in just before sending the packet. */
this->Send_uint16(0);
size_t size = EncodedLengthOfPacketSize();
if (cs != nullptr && cs->send_encryption_handler != nullptr) {
/* Allocate some space for the message authentication code of the encryption. */
size += cs->send_encryption_handler->MACSize();
}
assert(this->CanWriteToPacket(size));
this->buffer.resize(size, 0);
this->Send_uint8(type);
}
@@ -64,6 +71,13 @@ void Packet::PrepareToSend()
this->buffer[0] = GB(this->Size(), 0, 8);
this->buffer[1] = GB(this->Size(), 8, 8);
if (cs != nullptr && cs->send_encryption_handler != nullptr) {
size_t offset = EncodedLengthOfPacketSize();
size_t mac_size = cs->send_encryption_handler->MACSize();
size_t message_offset = offset + mac_size;
cs->send_encryption_handler->Encrypt(std::span(&this->buffer[offset], mac_size), std::span(&this->buffer[message_offset], this->buffer.size() - message_offset));
}
this->pos = 0; // We start reading from here
this->buffer.shrink_to_fit();
}
@@ -259,11 +273,21 @@ bool Packet::ParsePacketSize()
/**
* Prepares the packet so it can be read
* @return True when the packet was valid, otherwise false.
*/
void Packet::PrepareToRead()
bool Packet::PrepareToRead()
{
/* Put the position on the right place */
this->pos = static_cast<PacketSize>(EncodedLengthOfPacketSize());
if (cs == nullptr || cs->receive_encryption_handler == nullptr) return true;
size_t mac_size = cs->receive_encryption_handler->MACSize();
if (this->buffer.size() <= pos + mac_size) return false;
bool valid = cs->receive_encryption_handler->Decrypt(std::span(&this->buffer[pos], mac_size), std::span(&this->buffer[pos + mac_size], this->buffer.size() - pos - mac_size));
this->pos += static_cast<PacketSize>(mac_size);
return valid;
}
/**
@@ -273,7 +297,9 @@ void Packet::PrepareToRead()
PacketType Packet::GetPacketType() const
{
assert(this->Size() >= EncodedLengthOfPacketSize() + EncodedLengthOfPacketType());
return static_cast<PacketType>(buffer[EncodedLengthOfPacketSize()]);
size_t offset = EncodedLengthOfPacketSize();
if (cs != nullptr && cs->send_encryption_handler != nullptr) offset += cs->send_encryption_handler->MACSize();
return static_cast<PacketType>(buffer[offset]);
}
/**