transmission/libtransmission/upnp.cc

367 lines
10 KiB
C++

// This file Copyright © 2007-2022 Mnemosyne LLC.
// It may be used under GPLv2 (SPDX: GPL-2.0-only), GPLv3 (SPDX: GPL-3.0-only),
// or any future license endorsed by Mnemosyne LLC.
// License text can be found in the licenses/ folder.
#include <cerrno>
#include <future>
#include <mutex>
#include <string_view>
#include <thread>
#include <fmt/core.h>
#ifdef SYSTEM_MINIUPNP
#include <miniupnpc/miniupnpc.h>
#include <miniupnpc/upnpcommands.h>
#else
#include <miniupnp/miniupnpc.h>
#include <miniupnp/upnpcommands.h>
#endif
#include "transmission.h"
#include "log.h"
#include "port-forwarding.h"
#include "session.h"
#include "tr-assert.h"
#include "upnp.h"
#include "utils.h"
namespace
{
enum class UpnpState
{
IDLE,
FAILED,
WILL_DISCOVER, // next action is upnpDiscover()
DISCOVERING, // currently making blocking upnpDiscover() call in a worker thread
WILL_MAP, // next action is UPNP_AddPortMapping()
WILL_UNMAP // next action is UPNP_DeletePortMapping()
};
tr_port_forwarding portFwdState(UpnpState upnp_state, bool is_mapped)
{
switch (upnp_state)
{
case UpnpState::WILL_DISCOVER:
case UpnpState::DISCOVERING:
return TR_PORT_UNMAPPED;
case UpnpState::WILL_MAP:
return TR_PORT_MAPPING;
case UpnpState::WILL_UNMAP:
return TR_PORT_UNMAPPING;
case UpnpState::IDLE:
return is_mapped ? TR_PORT_MAPPED : TR_PORT_UNMAPPED;
default: // UpnpState::FAILED:
return TR_PORT_ERROR;
}
}
} // namespace
struct tr_upnp
{
~tr_upnp()
{
TR_ASSERT(!isMapped);
TR_ASSERT(
state == UpnpState::IDLE || state == UpnpState::FAILED || state == UpnpState::WILL_DISCOVER ||
state == UpnpState::DISCOVERING);
FreeUPNPUrls(&urls);
}
bool hasDiscovered = false;
UPNPUrls urls = {};
IGDdatas data = {};
tr_port port;
char lanaddr[16] = {};
bool isMapped = false;
UpnpState state = UpnpState::WILL_DISCOVER;
// Used to return the results of upnpDiscover() from a worker thread
// to be processed without blocking in tr_upnpPulse().
// This will be pending while the state is UpnpState::DISCOVERING.
std::optional<std::future<UPNPDev*>> discover_future;
};
/**
***
**/
tr_upnp* tr_upnpInit()
{
return new tr_upnp();
}
void tr_upnpClose(tr_upnp* handle)
{
delete handle;
}
/**
*** Wrappers for miniupnpc functions
**/
static struct UPNPDev* tr_upnpDiscover(int msec, char const* bindaddr)
{
UPNPDev* ret = nullptr;
auto have_err = bool{};
#if (MINIUPNPC_API_VERSION >= 8) /* adds ipv6 and error args */
int err = UPNPDISCOVER_SUCCESS;
#if (MINIUPNPC_API_VERSION >= 14) /* adds ttl */
ret = upnpDiscover(msec, bindaddr, nullptr, 0, 0, 2, &err);
#else
ret = upnpDiscover(msec, bindaddr, nullptr, 0, 0, &err);
#endif
have_err = err != UPNPDISCOVER_SUCCESS;
#else
ret = upnpDiscover(msec, bindaddr, nullptr, 0);
have_err = ret == nullptr;
#endif
if (have_err)
{
tr_logAddDebug(fmt::format("upnpDiscover failed: {} ({})", tr_strerror(errno), errno));
}
return ret;
}
static int tr_upnpGetSpecificPortMappingEntry(tr_upnp* handle, char const* proto)
{
char intClient[16];
char intPort[16];
*intClient = '\0';
*intPort = '\0';
auto const port_str = fmt::format(FMT_STRING("{:d}"), handle->port.host());
#if (MINIUPNPC_API_VERSION >= 10) /* adds remoteHost arg */
int const err = UPNP_GetSpecificPortMappingEntry(
handle->urls.controlURL,
handle->data.first.servicetype,
port_str.c_str(),
proto,
nullptr /*remoteHost*/,
intClient,
intPort,
nullptr /*desc*/,
nullptr /*enabled*/,
nullptr /*duration*/);
#elif (MINIUPNPC_API_VERSION >= 8) /* adds desc, enabled and leaseDuration args */
int const err = UPNP_GetSpecificPortMappingEntry(
handle->urls.controlURL,
handle->data.first.servicetype,
port_str.c_str(),
proto,
intClient,
intPort,
nullptr /*desc*/,
nullptr /*enabled*/,
nullptr /*duration*/);
#else
int const err = UPNP_GetSpecificPortMappingEntry(
handle->urls.controlURL,
handle->data.first.servicetype,
port_str.c_str(),
proto,
intClient,
intPort);
#endif
return err;
}
static int tr_upnpAddPortMapping(tr_upnp const* handle, char const* proto, tr_port port, char const* desc)
{
int const old_errno = errno;
errno = 0;
auto const port_str = fmt::format(FMT_STRING("{:d}"), port.host());
#if (MINIUPNPC_API_VERSION >= 8)
int err = UPNP_AddPortMapping(
handle->urls.controlURL,
handle->data.first.servicetype,
port_str.c_str(),
port_str.c_str(),
handle->lanaddr,
desc,
proto,
nullptr,
nullptr);
#else
int err = UPNP_AddPortMapping(
handle->urls.controlURL,
handle->data.first.servicetype,
port_str.c_str(),
port_str.c_str(),
handle->lanaddr,
desc,
proto,
nullptr);
#endif
if (err != 0)
{
tr_logAddDebug(fmt::format("{} Port forwarding failed with error {}: {} ({})", proto, err, tr_strerror(errno), errno));
}
errno = old_errno;
return err;
}
static void tr_upnpDeletePortMapping(tr_upnp const* handle, char const* proto, tr_port port)
{
auto const port_str = fmt::format(FMT_STRING("{:d}"), port.host());
UPNP_DeletePortMapping(handle->urls.controlURL, handle->data.first.servicetype, port_str.c_str(), proto, nullptr);
}
/**
***
**/
enum
{
UPNP_IGD_NONE = 0,
UPNP_IGD_VALID_CONNECTED = 1,
UPNP_IGD_VALID_NOT_CONNECTED = 2,
UPNP_IGD_INVALID = 3
};
static auto* discoverThreadfunc(char* bindaddr)
{
auto* const ret = tr_upnpDiscover(2000, bindaddr);
tr_free(bindaddr);
return ret;
}
template<typename T>
static bool isFutureReady(std::future<T> const& future)
{
return future.wait_for(std::chrono::seconds(0)) == std::future_status::ready;
}
tr_port_forwarding tr_upnpPulse(tr_upnp* handle, tr_port port, bool isEnabled, bool doPortCheck, char const* bindaddr)
{
if (isEnabled && handle->state == UpnpState::WILL_DISCOVER)
{
TR_ASSERT(!handle->discover_future);
auto task = std::packaged_task<UPNPDev*(char*)>{ discoverThreadfunc };
handle->discover_future = task.get_future();
handle->state = UpnpState::DISCOVERING;
std::thread(std::move(task), tr_strdup(bindaddr)).detach();
}
if (isEnabled && handle->state == UpnpState::DISCOVERING && handle->discover_future &&
isFutureReady(*handle->discover_future))
{
auto* const devlist = handle->discover_future->get();
handle->discover_future.reset();
FreeUPNPUrls(&handle->urls);
if (UPNP_GetValidIGD(devlist, &handle->urls, &handle->data, handle->lanaddr, sizeof(handle->lanaddr)) ==
UPNP_IGD_VALID_CONNECTED)
{
tr_logAddInfo(fmt::format(_("Found Internet Gateway Device '{url}'"), fmt::arg("url", handle->urls.controlURL)));
tr_logAddInfo(fmt::format(_("Local Address is '{address}'"), fmt::arg("address", handle->lanaddr)));
handle->state = UpnpState::IDLE;
handle->hasDiscovered = true;
}
else
{
handle->state = UpnpState::FAILED;
tr_logAddDebug(fmt::format("UPNP_GetValidIGD failed: {} ({})", tr_strerror(errno), errno));
tr_logAddDebug("If your router supports UPnP, please make sure UPnP is enabled!");
}
freeUPNPDevlist(devlist);
}
if ((handle->state == UpnpState::IDLE) && (handle->isMapped) && (!isEnabled || handle->port != port))
{
handle->state = UpnpState::WILL_UNMAP;
}
if (isEnabled && handle->isMapped && doPortCheck &&
((tr_upnpGetSpecificPortMappingEntry(handle, "TCP") != UPNPCOMMAND_SUCCESS) ||
(tr_upnpGetSpecificPortMappingEntry(handle, "UDP") != UPNPCOMMAND_SUCCESS)))
{
tr_logAddInfo(fmt::format(_("Port {port} is not forwarded"), fmt::arg("port", handle->port.host())));
handle->isMapped = false;
}
if (handle->state == UpnpState::WILL_UNMAP)
{
tr_upnpDeletePortMapping(handle, "TCP", handle->port);
tr_upnpDeletePortMapping(handle, "UDP", handle->port);
tr_logAddInfo(fmt::format(
_("Stopping port forwarding through '{url}', service '{type}'"),
fmt::arg("url", handle->urls.controlURL),
fmt::arg("type", handle->data.first.servicetype)));
handle->isMapped = false;
handle->state = UpnpState::IDLE;
handle->port = {};
}
if ((handle->state == UpnpState::IDLE) && isEnabled && !handle->isMapped)
{
handle->state = UpnpState::WILL_MAP;
}
if (handle->state == UpnpState::WILL_MAP)
{
errno = 0;
if (handle->urls.controlURL == nullptr)
{
handle->isMapped = false;
}
else
{
auto const desc = fmt::format(FMT_STRING("{:s} at {:d}"), TR_NAME, port.host());
int const err_tcp = tr_upnpAddPortMapping(handle, "TCP", port, desc.c_str());
int const err_udp = tr_upnpAddPortMapping(handle, "UDP", port, desc.c_str());
handle->isMapped = err_tcp == 0 || err_udp == 0;
}
tr_logAddDebug(fmt::format(
_("Port forwarding through '{url}', service '{type}'. (local address: {address}:{port})"),
fmt::arg("url", handle->urls.controlURL),
fmt::arg("type", handle->data.first.servicetype),
fmt::arg("address", handle->lanaddr),
fmt::arg("port", port.host())));
if (handle->isMapped)
{
tr_logAddInfo(fmt::format(_("Port {port} is forwarded"), fmt::arg("port", port.host())));
handle->port = port;
handle->state = UpnpState::IDLE;
}
else
{
tr_logAddInfo(_("If your router supports UPnP, please make sure UPnP is enabled!"));
handle->port = {};
handle->state = UpnpState::FAILED;
}
}
return portFwdState(handle->state, handle->isMapped);
}