modules/bouncedcc.cpp
Rama master · réplica de lectura del repositorio original.
/*
* Copyright (C) 2004-2026 ZNC, see the NOTICE file for details.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <znc/User.h>
#include <znc/IRCNetwork.h>
using std::set;
class CBounceDCCMod;
class CDCCBounce : public CSocket {
public:
CDCCBounce(CBounceDCCMod* pMod, unsigned long uLongIP, unsigned short uPort,
const CString& sFileName, const CString& sRemoteNick,
const CString& sRemoteIP, bool bIsChat = false);
CDCCBounce(CBounceDCCMod* pMod, const CString& sHostname,
unsigned short uPort, const CString& sRemoteNick,
const CString& sRemoteIP, const CString& sFileName,
int iTimeout = 60, bool bIsChat = false);
~CDCCBounce() override;
static unsigned short DCCRequest(const CString& sNick,
unsigned long uLongIP,
unsigned short uPort,
const CString& sFileName, bool bIsChat,
CBounceDCCMod* pMod,
const CString& sRemoteIP);
void ReadLine(const CString& sData) override;
void ReadData(const char* data, size_t len) override;
void ReadPaused() override;
void Timeout() override;
void ConnectionRefused() override;
void ReachedMaxBuffer() override;
void SockError(int iErrno, const CString& sDescription) override;
void Connected() override;
void Disconnected() override;
Csock* GetSockObj(const CString& sHost, unsigned short uPort) override;
void Shutdown();
void PutServ(const CString& sLine);
void PutPeer(const CString& sLine);
bool IsPeerConnected() {
return (m_pPeer) ? m_pPeer->IsConnected() : false;
}
// Setters
void SetPeer(CDCCBounce* p) { m_pPeer = p; }
void SetRemoteIP(const CString& s) { m_sRemoteIP = s; }
void SetRemoteNick(const CString& s) { m_sRemoteNick = s; }
void SetRemote(bool b) { m_bIsRemote = b; }
// !Setters
// Getters
unsigned short GetUserPort() const { return m_uRemotePort; }
const CString& GetRemoteAddr() const { return m_sRemoteIP; }
const CString& GetRemoteNick() const { return m_sRemoteNick; }
const CString& GetFileName() const { return m_sFileName; }
CDCCBounce* GetPeer() const { return m_pPeer; }
bool IsRemote() { return m_bIsRemote; }
bool IsChat() { return m_bIsChat; }
// !Getters
private:
protected:
CString m_sRemoteNick;
CString m_sRemoteIP;
CString m_sConnectIP;
CString m_sLocalIP;
CString m_sFileName;
CBounceDCCMod* m_pModule;
CDCCBounce* m_pPeer;
unsigned short m_uRemotePort;
bool m_bIsChat;
bool m_bIsRemote;
static const unsigned int m_uiMaxDCCBuffer;
static const unsigned int m_uiMinDCCBuffer;
};
// If we buffer more than this in memory, we will throttle the receiving side
const unsigned int CDCCBounce::m_uiMaxDCCBuffer = 10 * 1024;
// If less than this is in the buffer, the receiving side continues
const unsigned int CDCCBounce::m_uiMinDCCBuffer = 2 * 1024;
class CBounceDCCMod : public CModule {
public:
void ListDCCsCommand(const CString& sLine) {
CTable Table;
Table.AddColumn(t_s("Type", "list"));
Table.AddColumn(t_s("State", "list"));
Table.AddColumn(t_s("Speed", "list"));
Table.AddColumn(t_s("Nick", "list"));
Table.AddColumn(t_s("IP", "list"));
Table.AddColumn(t_s("File", "list"));
set<CSocket*>::const_iterator it;
for (it = BeginSockets(); it != EndSockets(); ++it) {
CDCCBounce* pSock = (CDCCBounce*)*it;
CString sSockName = pSock->GetSockName();
if (!(pSock->IsRemote())) {
Table.AddRow();
Table.SetCell(t_s("Nick", "list"), pSock->GetRemoteNick());
Table.SetCell(t_s("IP", "list"), pSock->GetRemoteAddr());
if (pSock->IsChat()) {
Table.SetCell(t_s("Type", "list"), t_s("Chat", "list"));
} else {
Table.SetCell(t_s("Type", "list"), t_s("Xfer", "list"));
Table.SetCell(t_s("File", "list"), pSock->GetFileName());
}
CString sState = t_s("Waiting");
if ((pSock->IsConnected()) || (pSock->IsPeerConnected())) {
sState = t_s("Halfway");
if ((pSock->IsConnected()) && (pSock->IsPeerConnected())) {
sState = t_s("Connected");
}
}
Table.SetCell(t_s("State", "list"), sState);
}
}
if (PutModule(Table) == 0) {
PutModule(t_s("You have no active DCCs."));
}
}
void UseClientIPCommand(const CString& sLine) {
CString sValue = sLine.Token(1, true);
if (!sValue.empty()) {
SetNV("UseClientIP", sValue);
}
PutModule(t_f("Use client IP: {1}")(GetNV("UseClientIP").ToBool()));
}
MODCONSTRUCTOR(CBounceDCCMod) {
AddHelpCommand();
AddCommand("ListDCCs", "", t_d("List all active DCCs"),
[this](const CString& sLine) { ListDCCsCommand(sLine); });
AddCommand("UseClientIP", "<true|false>",
t_d("Change the option to use IP of client"),
[this](const CString& sLine) { UseClientIPCommand(sLine); });
}
~CBounceDCCMod() override {}
CString GetLocalDCCIP() { return GetUser()->GetLocalDCCIP(); }
bool UseClientIP() { return GetNV("UseClientIP").ToBool(); }
bool IsClientIP(const CString& sIP) {
for (CClient* pClient : GetUser()->GetAllClients()) {
if (pClient->GetRemoteIP().Equals(sIP)) return true;
}
return false;
}
// The address in a DCC request from IRC is chosen by the remote peer, and
// ZNC is the one connecting to it, so don't let it point at ZNC's own
// host or at link-local services.
static bool IsAllowedPeerIP(unsigned long uLongIP) {
if (uLongIP > 0xFFFFFFFFUL) return false;
const unsigned long uFirst = uLongIP >> 24;
if (uFirst == 0 || uFirst == 127 || uFirst >= 224) return false;
if ((uLongIP >> 16) == 0xA9FE) return false; // 169.254.0.0/16
return true;
}
EModRet OnUserCTCPMessage(CCTCPMessage& Message) override {
CString sTarget = Message.GetTarget();
CString sMessage = Message.GetText();
if (sMessage.StartsWith("DCC ")) {
CString sType =
sMessage.Token(1, false, " ", false, "\"", "\"", true);
CString sFile =
sMessage.Token(2, false, " ", false, "\"", "\"", false);
unsigned long uLongIP = sMessage.Token(3, false, " ", false, "\"",
"\"", true).ToULong();
unsigned short uPort = sMessage.Token(4, false, " ", false, "\"",
"\"", true).ToUShort();
unsigned long uFileSize = sMessage.Token(5, false, " ", false, "\"",
"\"", true).ToULong();
CString sIP = GetLocalDCCIP();
if (!UseClientIP()) {
uLongIP = CUtils::GetLongIP(GetClient()->GetRemoteIP());
}
if (sType.Equals("CHAT")) {
unsigned short uBNCPort = CDCCBounce::DCCRequest(
sTarget, uLongIP, uPort, "", true, this, "");
if (uBNCPort) {
PutIRC("PRIVMSG " + sTarget + " :\001DCC CHAT chat " +
CString(CUtils::GetLongIP(sIP)) + " " +
CString(uBNCPort) + "\001");
}
} else if (sType.Equals("SEND")) {
// DCC SEND readme.txt 403120438 5550 1104
unsigned short uBNCPort = CDCCBounce::DCCRequest(
sTarget, uLongIP, uPort, sFile, false, this, "");
if (uBNCPort) {
PutIRC("PRIVMSG " + sTarget + " :\001DCC SEND " + sFile +
" " + CString(CUtils::GetLongIP(sIP)) + " " +
CString(uBNCPort) + " " + CString(uFileSize) +
"\001");
}
} else if (sType.Equals("RESUME")) {
// PRIVMSG user :DCC RESUME "znc.o" 58810 151552
unsigned short uResumePort = sMessage.Token(3).ToUShort();
set<CSocket*>::const_iterator it;
for (it = BeginSockets(); it != EndSockets(); ++it) {
CDCCBounce* pSock = (CDCCBounce*)*it;
if (pSock->GetLocalPort() == uResumePort) {
PutIRC("PRIVMSG " + sTarget + " :\001DCC " + sType +
" " + sFile + " " +
CString(pSock->GetUserPort()) + " " +
sMessage.Token(4) + "\001");
}
}
} else if (sType.Equals("ACCEPT")) {
// Need to lookup the connection by port, filter the port, and
// forward to the user
set<CSocket*>::const_iterator it;
for (it = BeginSockets(); it != EndSockets(); ++it) {
CDCCBounce* pSock = (CDCCBounce*)*it;
if (pSock->GetUserPort() == sMessage.Token(3).ToUShort()) {
PutIRC("PRIVMSG " + sTarget + " :\001DCC " + sType +
" " + sFile + " " +
CString(pSock->GetLocalPort()) + " " +
sMessage.Token(4) + "\001");
}
}
}
return HALTCORE;
}
return CONTINUE;
}
EModRet OnPrivCTCPMessage(CCTCPMessage& Message) override {
const CNick& Nick = Message.GetNick();
CString sMessage = Message.GetText();
CIRCNetwork* pNetwork = GetNetwork();
if (sMessage.StartsWith("DCC ") && pNetwork->IsUserAttached()) {
// DCC CHAT chat 2453612361 44592
CString sType =
sMessage.Token(1, false, " ", false, "\"", "\"", true);
CString sFile =
sMessage.Token(2, false, " ", false, "\"", "\"", false);
unsigned long uLongIP = sMessage.Token(3, false, " ", false, "\"",
"\"", true).ToULong();
unsigned short uPort = sMessage.Token(4, false, " ", false, "\"",
"\"", true).ToUShort();
unsigned long uFileSize = sMessage.Token(5, false, " ", false, "\"",
"\"", true).ToULong();
if ((sType.Equals("CHAT") || sType.Equals("SEND")) &&
!IsAllowedPeerIP(uLongIP)) {
PutModule(t_f("DCC {1} from {2} refused: bad address {3}")(
sType, Nick.GetNick(), CString(uLongIP)));
return HALTCORE;
}
if (sType.Equals("CHAT")) {
CNick FromNick(Nick.GetNickMask());
unsigned short uBNCPort = CDCCBounce::DCCRequest(
FromNick.GetNick(), uLongIP, uPort, "", true, this,
CUtils::GetIP(uLongIP));
if (uBNCPort) {
CString sIP = GetLocalDCCIP();
PutUser(":" + Nick.GetNickMask() + " PRIVMSG " +
pNetwork->GetCurNick() + " :\001DCC CHAT chat " +
CString(CUtils::GetLongIP(sIP)) + " " +
CString(uBNCPort) + "\001");
}
} else if (sType.Equals("SEND")) {
// DCC SEND readme.txt 403120438 5550 1104
unsigned short uBNCPort = CDCCBounce::DCCRequest(
Nick.GetNick(), uLongIP, uPort, sFile, false, this,
CUtils::GetIP(uLongIP));
if (uBNCPort) {
CString sIP = GetLocalDCCIP();
PutUser(":" + Nick.GetNickMask() + " PRIVMSG " +
pNetwork->GetCurNick() + " :\001DCC SEND " + sFile +
" " + CString(CUtils::GetLongIP(sIP)) + " " +
CString(uBNCPort) + " " + CString(uFileSize) +
"\001");
}
} else if (sType.Equals("RESUME")) {
// Need to lookup the connection by port, filter the port, and
// forward to the user
unsigned short uResumePort = sMessage.Token(3).ToUShort();
set<CSocket*>::const_iterator it;
for (it = BeginSockets(); it != EndSockets(); ++it) {
CDCCBounce* pSock = (CDCCBounce*)*it;
if (pSock->GetLocalPort() == uResumePort) {
PutUser(":" + Nick.GetNickMask() + " PRIVMSG " +
pNetwork->GetCurNick() + " :\001DCC " + sType +
" " + sFile + " " +
CString(pSock->GetUserPort()) + " " +
sMessage.Token(4) + "\001");
}
}
} else if (sType.Equals("ACCEPT")) {
// Need to lookup the connection by port, filter the port, and
// forward to the user
set<CSocket*>::const_iterator it;
for (it = BeginSockets(); it != EndSockets(); ++it) {
CDCCBounce* pSock = (CDCCBounce*)*it;
if (pSock->GetUserPort() == sMessage.Token(3).ToUShort()) {
PutUser(":" + Nick.GetNickMask() + " PRIVMSG " +
pNetwork->GetCurNick() + " :\001DCC " + sType +
" " + sFile + " " +
CString(pSock->GetLocalPort()) + " " +
sMessage.Token(4) + "\001");
}
}
}
return HALTCORE;
}
return CONTINUE;
}
};
CDCCBounce::CDCCBounce(CBounceDCCMod* pMod, unsigned long uLongIP,
unsigned short uPort, const CString& sFileName,
const CString& sRemoteNick, const CString& sRemoteIP,
bool bIsChat)
: CSocket(pMod) {
m_uRemotePort = uPort;
m_sConnectIP = CUtils::GetIP(uLongIP);
m_sRemoteIP = sRemoteIP;
m_sFileName = sFileName;
m_sRemoteNick = sRemoteNick;
m_pModule = pMod;
m_bIsChat = bIsChat;
m_sLocalIP = pMod->GetLocalDCCIP();
m_pPeer = nullptr;
m_bIsRemote = false;
if (bIsChat) {
EnableReadLine();
} else {
DisableReadLine();
}
}
CDCCBounce::CDCCBounce(CBounceDCCMod* pMod, const CString& sHostname,
unsigned short uPort, const CString& sRemoteNick,
const CString& sRemoteIP, const CString& sFileName,
int iTimeout, bool bIsChat)
: CSocket(pMod, sHostname, uPort, iTimeout) {
m_uRemotePort = 0;
m_bIsChat = bIsChat;
m_pModule = pMod;
m_pPeer = nullptr;
m_sRemoteNick = sRemoteNick;
m_sFileName = sFileName;
m_sRemoteIP = sRemoteIP;
m_bIsRemote = false;
SetMaxBufferThreshold(10240);
if (bIsChat) {
EnableReadLine();
} else {
DisableReadLine();
}
}
CDCCBounce::~CDCCBounce() {
if (m_pPeer) {
m_pPeer->Shutdown();
m_pPeer = nullptr;
}
}
void CDCCBounce::ReadLine(const CString& sData) {
CString sLine = sData.TrimRight_n("\r\n");
DEBUG(GetSockName() << " <- [" << sLine << "]");
PutPeer(sLine);
}
void CDCCBounce::ReachedMaxBuffer() {
DEBUG(GetSockName() << " == ReachedMaxBuffer()");
CString sType = m_bIsChat ? t_s("Chat", "type") : t_s("Xfer", "type");
m_pModule->PutModule(t_f("DCC {1} Bounce ({2}): Too long line received")(
sType, m_sRemoteNick));
Close();
}
void CDCCBounce::ReadData(const char* data, size_t len) {
if (m_pPeer) {
m_pPeer->Write(data, len);
size_t BufLen = m_pPeer->GetInternalWriteBuffer().length();
if (BufLen >= m_uiMaxDCCBuffer) {
DEBUG(GetSockName() << " The send buffer is over the "
"limit (" << BufLen << "), throttling");
PauseRead();
}
}
}
void CDCCBounce::ReadPaused() {
if (!m_pPeer ||
m_pPeer->GetInternalWriteBuffer().length() <= m_uiMinDCCBuffer)
UnPauseRead();
}
void CDCCBounce::Timeout() {
DEBUG(GetSockName() << " == Timeout()");
CString sType = m_bIsChat ? t_s("Chat", "type") : t_s("Xfer", "type");
if (IsRemote()) {
CString sHost = Csock::GetHostName();
if (!sHost.empty()) {
m_pModule->PutModule(t_f(
"DCC {1} Bounce ({2}): Timeout while connecting to {3} {4}")(
sType, m_sRemoteNick, sHost, Csock::GetPort()));
} else {
m_pModule->PutModule(
t_f("DCC {1} Bounce ({2}): Timeout while connecting.")(
sType, m_sRemoteNick));
}
} else {
m_pModule->PutModule(t_f(
"DCC {1} Bounce ({2}): Timeout while waiting for incoming "
"connection on {3} {4}")(sType, m_sRemoteNick, Csock::GetLocalIP(),
Csock::GetLocalPort()));
}
}
void CDCCBounce::ConnectionRefused() {
DEBUG(GetSockName() << " == ConnectionRefused()");
CString sType = m_bIsChat ? t_s("Chat", "type") : t_s("Xfer", "type");
CString sHost = Csock::GetHostName();
if (!sHost.empty()) {
m_pModule->PutModule(
t_f("DCC {1} Bounce ({2}): Connection refused while connecting to "
"{3} {4}")(sType, m_sRemoteNick, sHost, Csock::GetPort()));
} else {
m_pModule->PutModule(
t_f("DCC {1} Bounce ({2}): Connection refused while connecting.")(
sType, m_sRemoteNick));
}
}
void CDCCBounce::SockError(int iErrno, const CString& sDescription) {
DEBUG(GetSockName() << " == SockError(" << iErrno << ")");
CString sType = m_bIsChat ? t_s("Chat", "type") : t_s("Xfer", "type");
if (IsRemote()) {
CString sHost = Csock::GetHostName();
if (!sHost.empty()) {
m_pModule->PutModule(t_f(
"DCC {1} Bounce ({2}): Socket error on {3} {4}: {5}")(
sType, m_sRemoteNick, sHost, Csock::GetPort(), sDescription));
} else {
m_pModule->PutModule(t_f("DCC {1} Bounce ({2}): Socket error: {3}")(
sType, m_sRemoteNick, sDescription));
}
} else {
m_pModule->PutModule(
t_f("DCC {1} Bounce ({2}): Socket error on {3} {4}: {5}")(
sType, m_sRemoteNick, Csock::GetLocalIP(),
Csock::GetLocalPort(), sDescription));
}
}
void CDCCBounce::Connected() {
SetTimeout(0);
DEBUG(GetSockName() << " == Connected()");
}
void CDCCBounce::Disconnected() {
DEBUG(GetSockName() << " == Disconnected()");
}
void CDCCBounce::Shutdown() {
m_pPeer = nullptr;
DEBUG(GetSockName() << " == Close(); because my peer told me to");
Close();
}
Csock* CDCCBounce::GetSockObj(const CString& sHost, unsigned short uPort) {
// m_sRemoteIP is only known up front when the request came from IRC. In
// that case ZNC connects out to the remote peer itself, so the only thing
// that should be connecting here is one of the user's own clients. Hand
// Csocket a throwaway socket that is closed straight away and keep
// listening for the real client.
if (!m_sRemoteIP.empty() && !m_pModule->IsClientIP(sHost)) {
DEBUG(GetSockName() << " == GetSockObj(" << sHost << ") refused");
CString sType = m_bIsChat ? t_s("Chat", "type") : t_s("Xfer", "type");
m_pModule->PutModule(
t_f("DCC {1} Bounce ({2}): Refused connection from {3}, which is "
"not one of your clients")(sType, m_sRemoteNick, sHost));
CDCCBounce* pRefused =
new CDCCBounce(m_pModule, sHost, uPort, m_sRemoteNick, m_sRemoteIP,
m_sFileName, m_bIsChat);
pRefused->Close();
return pRefused;
}
Close();
if (m_sRemoteIP.empty()) {
m_sRemoteIP = sHost;
}
CDCCBounce* pSock = new CDCCBounce(m_pModule, sHost, uPort, m_sRemoteNick,
m_sRemoteIP, m_sFileName, m_bIsChat);
CDCCBounce* pRemoteSock =
new CDCCBounce(m_pModule, sHost, uPort, m_sRemoteNick, m_sRemoteIP,
m_sFileName, m_bIsChat);
pSock->SetPeer(pRemoteSock);
pRemoteSock->SetPeer(pSock);
pRemoteSock->SetRemote(true);
pSock->SetRemote(false);
CZNC::Get().GetManager().Connect(
m_sConnectIP, m_uRemotePort,
"DCC::" + CString((m_bIsChat) ? "Chat" : "XFER") + "::Remote::" +
m_sRemoteNick,
60, false, m_sLocalIP, pRemoteSock);
pSock->SetSockName(GetSockName());
return pSock;
}
void CDCCBounce::PutServ(const CString& sLine) {
DEBUG(GetSockName() << " -> [" << sLine << "]");
Write(sLine + "\r\n");
}
void CDCCBounce::PutPeer(const CString& sLine) {
if (m_pPeer) {
m_pPeer->PutServ(sLine);
} else {
PutServ("*** Not connected yet ***");
}
}
unsigned short CDCCBounce::DCCRequest(const CString& sNick,
unsigned long uLongIP,
unsigned short uPort,
const CString& sFileName, bool bIsChat,
CBounceDCCMod* pMod,
const CString& sRemoteIP) {
CDCCBounce* pDCCBounce = new CDCCBounce(pMod, uLongIP, uPort, sFileName,
sNick, sRemoteIP, bIsChat);
unsigned short uListenPort = CZNC::Get().GetManager().ListenRand(
"DCC::" + CString((bIsChat) ? "Chat" : "Xfer") + "::Local::" + sNick,
pMod->GetLocalDCCIP(), false, SOMAXCONN, pDCCBounce, 120);
return uListenPort;
}
template <>
void TModInfo<CBounceDCCMod>(CModInfo& Info) {
Info.SetWikiPage("bouncedcc");
}
USERMODULEDEFS(CBounceDCCMod,
t_s("Bounces DCC transfers through ZNC instead of sending them "
"directly to the user. "))