r5sdk/r5dev/engine/shared/base_rcon.cpp
Kawe Mazidjatari 90e4711425 Tier2: move random generator from tier0 to tier2
Moved into cryptutils.cpp.
2024-06-01 11:25:58 +02:00

353 lines
10 KiB
C++

//===========================================================================//
//
// Purpose: Base rcon implementation.
//
//===========================================================================//
#include "core/stdafx.h"
#include "tier2/cryptutils.h"
#include "base_rcon.h"
#include "engine/net.h"
#include "shared_rcon.h"
#include "protoc/netcon.pb.h"
#include "mbedtls/base64.h"
//-----------------------------------------------------------------------------
// Purpose: sets the encryption key, a key will always be set, either random or
// the default key on failure
// Input : *pBase64NetKey -
// bUseDefaultOnFailure -
//-----------------------------------------------------------------------------
void CNetConBase::SetKey(const char* pBase64NetKey, const bool bUseDefaultOnFailure/* = false*/)
{
// Drop all connections as they would be unable to decipher the message
// frames once the key has been swapped.
m_Socket.CloseAllAcceptedSockets();
bool parseInput = pBase64NetKey && *pBase64NetKey;
bool genRandom = !parseInput;
bool failure = false;
if (parseInput)
{
const size_t keyLen = strlen(pBase64NetKey);
string tokenizedKey;
if (keyLen != AES_128_B64_ENCODED_SIZE || !IsValidBase64(pBase64NetKey, &tokenizedKey))
{
Error(eDLL_T::ENGINE, NO_ERROR, "RCON Key: invalid key (%s)\n", pBase64NetKey);
failure = true;
}
else
{
size_t numBytesDecoded = 0;
const int decodeRet = mbedtls_base64_decode(m_NetKey, sizeof(m_NetKey), &numBytesDecoded,
reinterpret_cast<const unsigned char*>(tokenizedKey.c_str()), tokenizedKey.length());
if (decodeRet != 0)
{
Error(eDLL_T::ENGINE, NO_ERROR, "RCON Key: decode error (%d)\n", decodeRet);
failure = true;
}
else if (numBytesDecoded != sizeof(m_NetKey))
{
Error(eDLL_T::ENGINE, NO_ERROR, "RCON Key: read error (%zu != %zu)\n", numBytesDecoded, sizeof(m_NetKey));
failure = true;
}
else
{
m_Base64NetKey = tokenizedKey.c_str();
}
}
}
bool useDefaultKey = false; // Last resort
if (genRandom || failure) // Generate random key
{
if (failure && bUseDefaultOnFailure)
{
useDefaultKey = true;
}
else
{
const char* errorMsg = nullptr;
if (!Plat_GenerateRandom(m_NetKey, sizeof(m_NetKey), errorMsg))
{
Error(eDLL_T::ENGINE, NO_ERROR, "RCON Key: generate error (%s)\n", errorMsg);
useDefaultKey = true;
}
else // Try to encode it
{
char encodedKey[45];
memset(encodedKey, 0, sizeof(encodedKey));
size_t numBytesEncoded = 0;
const int encodeRet = mbedtls_base64_encode(reinterpret_cast<unsigned char*>(&encodedKey),
sizeof(encodedKey), &numBytesEncoded, m_NetKey, sizeof(m_NetKey));
if (encodeRet != 0)
{
Error(eDLL_T::ENGINE, NO_ERROR, "RCON Key: encode error (%d)\n", encodeRet);
useDefaultKey = true;
}
else if (numBytesEncoded != AES_128_B64_ENCODED_SIZE)
{
Error(eDLL_T::ENGINE, NO_ERROR, "RCON Key: write error (%zu != %zu)\n", numBytesEncoded, AES_128_B64_ENCODED_SIZE);
failure = true;
}
else
{
m_Base64NetKey = encodedKey;
}
}
}
}
if (useDefaultKey) // Use the default key if everything failed (unlikely)
{
size_t numBytesDecoded = 0;
mbedtls_base64_decode(m_NetKey, sizeof(m_NetKey), &numBytesDecoded,
reinterpret_cast<const unsigned char*>(DEFAULT_NET_ENCRYPTION_KEY), AES_128_B64_ENCODED_SIZE);
m_Base64NetKey = DEFAULT_NET_ENCRYPTION_KEY;
}
}
//-----------------------------------------------------------------------------
// Purpose: gets the encryption key as a base64 encoded string
//-----------------------------------------------------------------------------
const char* CNetConBase::GetKey(void) const
{
return m_Base64NetKey.String();
}
//-----------------------------------------------------------------------------
// Purpose: connect to remote
// Input : *pHostName -
// nPort -
// Output : true on success, false otherwise
//-----------------------------------------------------------------------------
bool CNetConBase::Connect(const char* pHostName, const int nPort)
{
return CL_NetConConnect(this, pHostName, nPort);
}
//-----------------------------------------------------------------------------
// Purpose: parses input response buffer using length-prefix framing
// Input : &data -
// *pRecvBuf -
// nRecvLen -
// nMaxLen -
// Output: true on success, false otherwise
//-----------------------------------------------------------------------------
bool CNetConBase::ProcessBuffer(CConnectedNetConsoleData& data,
const char* pRecvBuf, int nRecvLen, const int nMaxLen)
{
bool bSuccess = true;
while (nRecvLen > 0)
{
if (data.m_nPayloadLen)
{
if (data.m_nPayloadRead < data.m_nPayloadLen)
{
data.m_RecvBuffer[data.m_nPayloadRead++] = *pRecvBuf;
pRecvBuf++;
nRecvLen--;
}
if (data.m_nPayloadRead == data.m_nPayloadLen)
{
if (!ProcessMessage(
reinterpret_cast<const char*>(data.m_RecvBuffer.data()), data.m_nPayloadLen)
&& bSuccess)
{
bSuccess = false;
}
data.m_nPayloadLen = 0;
data.m_nPayloadRead = 0;
}
}
else if (data.m_nPayloadRead < sizeof(int)) // Read size field.
{
data.m_RecvBuffer[data.m_nPayloadRead++] = *pRecvBuf;
pRecvBuf++;
nRecvLen--;
}
else // Build prefix.
{
data.m_nPayloadLen = int(ntohl(*reinterpret_cast<u_long*>(&data.m_RecvBuffer[0])));
data.m_nPayloadRead = 0;
if (!data.m_bAuthorized && nMaxLen > -1)
{
if (data.m_nPayloadLen > nMaxLen)
{
Disconnect("overflow"); // Sending large messages while not authenticated.
return false;
}
}
if (data.m_nPayloadLen < 0 ||
data.m_nPayloadLen > data.m_RecvBuffer.max_size())
{
Error(eDLL_T::ENGINE, NO_ERROR, "RCON Cmd: sync error (%d)\n", data.m_nPayloadLen);
Disconnect("desync"); // Out of sync (irrecoverable).
return false;
}
else
{
data.m_RecvBuffer.resize(data.m_nPayloadLen);
}
}
}
return bSuccess;
}
//-----------------------------------------------------------------------------
// Purpose: encrypt message to buffer
// Input : &ctx -
// *pInBuf -
// *pOutBuf -
// nDataLen -
// Output : true on success, false otherwise
//-----------------------------------------------------------------------------
bool CNetConBase::Encrypt(CryptoContext_s& ctx, const char* pInBuf,
char* pOutBuf, const size_t nDataLen) const
{
if (Crypto_GenerateIV(ctx, reinterpret_cast<const unsigned char*>(pInBuf), nDataLen))
return Crypto_CTREncrypt(ctx, reinterpret_cast<const unsigned char*>(pInBuf),
reinterpret_cast<unsigned char*>(pOutBuf), m_NetKey, nDataLen);
return false; // failure
}
//-----------------------------------------------------------------------------
// Purpose: decrypt message to buffer
// Input : &ctx -
// *pInBuf -
// *pOutBuf -
// nDataLen -
// Output : true on success, false otherwise
//-----------------------------------------------------------------------------
bool CNetConBase::Decrypt(CryptoContext_s& ctx, const char* pInBuf,
char* pOutBuf, const size_t nDataLen) const
{
return Crypto_CTRDecrypt(ctx, reinterpret_cast<const unsigned char*>(pInBuf),
reinterpret_cast<unsigned char*>(pOutBuf), m_NetKey, nDataLen);
}
//-----------------------------------------------------------------------------
// Purpose: encode message to buffer
// Input : *pMsg -
// *pMsgBuf -
// nMsgLen -
// Output : true on success, false otherwise
//-----------------------------------------------------------------------------
bool CNetConBase::Encode(google::protobuf::MessageLite* pMsg,
char* pMsgBuf, const size_t nMsgLen) const
{
return pMsg->SerializeToArray(pMsgBuf, int(nMsgLen));
}
//-----------------------------------------------------------------------------
// Purpose: decode message from buffer
// Input : *pMsg -
// *pMsgBuf -
// nMsgLen -
// Output : true on success, false otherwise
//-----------------------------------------------------------------------------
bool CNetConBase::Decode(google::protobuf::MessageLite* pMsg,
const char* pMsgBuf, const size_t nMsgLen) const
{
return pMsg->ParseFromArray(pMsgBuf, int(nMsgLen));
}
//-----------------------------------------------------------------------------
// Purpose: send message to specific connected socket
// Input : hSocket -
// *pMsgBuf -
// nMsgLen -
// Output: true on success, false otherwise
//-----------------------------------------------------------------------------
bool CNetConBase::Send(const SocketHandle_t hSocket, const char* pMsgBuf,
const int nMsgLen) const
{
std::ostringstream sendbuf;
const u_long nLen = htonl(u_long(nMsgLen));
sendbuf.write(reinterpret_cast<const char*>(&nLen), sizeof(u_long));
sendbuf.write(pMsgBuf, nMsgLen);
int ret = ::send(hSocket, sendbuf.str().data(), int(sendbuf.str().size()),
MSG_NOSIGNAL);
return (ret != SOCKET_ERROR);
}
//-----------------------------------------------------------------------------
// Purpose: receive message
// Input : &data -
// nMaxLen -
// Output: true on success, false otherwise
//-----------------------------------------------------------------------------
void CNetConBase::Recv(CConnectedNetConsoleData& data, const int nMaxLen)
{
static char szRecvBuf[1024];
{//////////////////////////////////////////////
const int nPendingLen = ::recv(data.m_hSocket, szRecvBuf, sizeof(char), MSG_PEEK);
if (nPendingLen == SOCKET_ERROR && m_Socket.IsSocketBlocking())
{
return;
}
else if (nPendingLen == 0) // Socket was closed.
{
Disconnect("remote closed socket");
return;
}
else if (nPendingLen < 0)
{
Disconnect("socket closed unexpectedly");
return;
}
}//////////////////////////////////////////////
int nReadLen = 0; // Find out how much we have to read.
int iResult = ::ioctlsocket(data.m_hSocket, FIONREAD, reinterpret_cast<u_long*>(&nReadLen));
if (iResult == SOCKET_ERROR)
{
Error(eDLL_T::ENGINE, NO_ERROR, "RCON Cmd: ioctl(%s) error (%s)\n", "FIONREAD", NET_ErrorString(WSAGetLastError()));
return;
}
while (nReadLen > 0)
{
const int nRecvLen = ::recv(data.m_hSocket, szRecvBuf, MIN(sizeof(szRecvBuf), nReadLen), MSG_NOSIGNAL);
if (nRecvLen == 0) // Socket was closed.
{
Disconnect("socket closed");
break;
}
if (nRecvLen < 0 && !m_Socket.IsSocketBlocking())
{
Error(eDLL_T::ENGINE, NO_ERROR, "RCON Cmd: recv error (%s)\n", NET_ErrorString(WSAGetLastError()));
break;
}
nReadLen -= nRecvLen; // Process what we've got.
ProcessBuffer(data, szRecvBuf, nRecvLen, nMaxLen);
}
return;
}