lokinet/llarp/path/path.hpp
2019-05-19 23:11:07 +01:00

733 lines
19 KiB
C++

#ifndef LLARP_PATH_HPP
#define LLARP_PATH_HPP
#include <crypto/encrypted_frame.hpp>
#include <crypto/types.hpp>
#include <messages/relay.hpp>
#include <path/path_types.hpp>
#include <path/pathbuilder.hpp>
#include <path/pathset.hpp>
#include <router_id.hpp>
#include <routing/handler.hpp>
#include <routing/message.hpp>
#include <service/intro.hpp>
#include <util/aligned.hpp>
#include <util/compare_ptr.hpp>
#include <util/threading.hpp>
#include <util/time.hpp>
#include <algorithm>
#include <functional>
#include <list>
#include <map>
#include <unordered_map>
#include <vector>
namespace llarp
{
class Logic;
struct AbstractRouter;
struct Crypto;
struct LR_CommitMessage;
struct LR_CommitRecord;
namespace path
{
/// maximum path length
constexpr size_t max_len = 8;
/// default path length
constexpr size_t default_len = 4;
/// pad messages to the nearest this many bytes
constexpr size_t pad_size = 128;
/// default path lifetime in ms
constexpr llarp_time_t default_lifetime = 10 * 60 * 1000;
/// after this many ms a path build times out
constexpr llarp_time_t build_timeout = 15000;
/// measure latency every this interval ms
constexpr llarp_time_t latency_interval = 5000;
/// if a path is inactive for this amount of time it's dead
constexpr llarp_time_t alive_timeout = 60000;
struct TransitHopInfo
{
TransitHopInfo() = default;
TransitHopInfo(const RouterID& down, const LR_CommitRecord& record);
PathID_t txID, rxID;
RouterID upstream;
RouterID downstream;
std::ostream&
print(std::ostream& stream, int level, int spaces) const;
bool
operator==(const TransitHopInfo& other) const
{
return txID == other.txID && rxID == other.rxID
&& upstream == other.upstream && downstream == other.downstream;
}
bool
operator!=(const TransitHopInfo& other) const
{
return !(*this == other);
}
bool
operator<(const TransitHopInfo& other) const
{
return txID < other.txID || rxID < other.rxID
|| upstream < other.upstream || downstream < other.downstream;
}
struct PathIDHash
{
std::size_t
operator()(const PathID_t& a) const
{
return AlignedBuffer< PathID_t::SIZE >::Hash()(a);
}
};
struct Hash
{
std::size_t
operator()(TransitHopInfo const& a) const
{
std::size_t idx0 = RouterID::Hash()(a.upstream);
std::size_t idx1 = RouterID::Hash()(a.downstream);
std::size_t idx2 = PathIDHash()(a.txID);
std::size_t idx3 = PathIDHash()(a.rxID);
return idx0 ^ idx1 ^ idx2 ^ idx3;
}
};
};
inline std::ostream&
operator<<(std::ostream& out, const TransitHopInfo& info)
{
return info.print(out, -1, -1);
}
struct IHopHandler
{
virtual ~IHopHandler()
{
}
virtual bool
Expired(llarp_time_t now) const = 0;
virtual bool
ExpiresSoon(llarp_time_t now, llarp_time_t dlt) const = 0;
/// send routing message and increment sequence number
virtual bool
SendRoutingMessage(const routing::IMessage& msg, AbstractRouter* r) = 0;
// handle data in upstream direction
virtual bool
HandleUpstream(const llarp_buffer_t& X, const TunnelNonce& Y,
AbstractRouter* r) = 0;
// handle data in downstream direction
virtual bool
HandleDownstream(const llarp_buffer_t& X, const TunnelNonce& Y,
AbstractRouter* r) = 0;
/// return timestamp last remote activity happened at
virtual llarp_time_t
LastRemoteActivityAt() const = 0;
uint64_t
NextSeqNo()
{
return m_SequenceNum++;
}
protected:
uint64_t m_SequenceNum = 0;
};
using HopHandler_ptr = std::shared_ptr< IHopHandler >;
struct TransitHop : public IHopHandler, public routing::IMessageHandler
{
TransitHop();
TransitHopInfo info;
SharedSecret pathKey;
ShortHash nonceXOR;
llarp_time_t started = 0;
// 10 minutes default
llarp_time_t lifetime = default_lifetime;
llarp_proto_version_t version;
llarp_time_t m_LastActivity = 0;
bool
IsEndpoint(const RouterID& us) const
{
return info.upstream == us;
}
llarp_time_t
ExpireTime() const;
llarp_time_t
LastRemoteActivityAt() const override
{
return m_LastActivity;
}
std::ostream&
print(std::ostream& stream, int level, int spaces) const;
bool
Expired(llarp_time_t now) const override;
bool
ExpiresSoon(llarp_time_t now, llarp_time_t dlt) const override
{
return now >= ExpireTime() - dlt;
}
// send routing message when end of path
bool
SendRoutingMessage(const routing::IMessage& msg,
AbstractRouter* r) override;
// handle routing message when end of path
bool
HandleRoutingMessage(const routing::IMessage& msg, AbstractRouter* r);
bool
HandleDataDiscardMessage(const routing::DataDiscardMessage& msg,
AbstractRouter* r) override;
bool
HandlePathConfirmMessage(const routing::PathConfirmMessage& msg,
AbstractRouter* r) override;
bool
HandlePathTransferMessage(const routing::PathTransferMessage& msg,
AbstractRouter* r) override;
bool
HandlePathLatencyMessage(const routing::PathLatencyMessage& msg,
AbstractRouter* r) override;
bool
HandleObtainExitMessage(const routing::ObtainExitMessage& msg,
AbstractRouter* r) override;
bool
HandleUpdateExitVerifyMessage(const routing::UpdateExitVerifyMessage& msg,
AbstractRouter* r) override;
bool
HandleTransferTrafficMessage(const routing::TransferTrafficMessage& msg,
AbstractRouter* r) override;
bool
HandleUpdateExitMessage(const routing::UpdateExitMessage& msg,
AbstractRouter* r) override;
bool
HandleGrantExitMessage(const routing::GrantExitMessage& msg,
AbstractRouter* r) override;
bool
HandleRejectExitMessage(const routing::RejectExitMessage& msg,
AbstractRouter* r) override;
bool
HandleCloseExitMessage(const routing::CloseExitMessage& msg,
AbstractRouter* r) override;
bool
HandleHiddenServiceFrame(
ABSL_ATTRIBUTE_UNUSED const service::ProtocolFrame& frame) override
{
/// TODO: implement me
LogWarn("Got hidden service data on transit hop");
return false;
}
bool
HandleGotIntroMessage(const dht::GotIntroMessage& msg);
bool
HandleDHTMessage(const dht::IMessage& msg, AbstractRouter* r) override;
// handle data in upstream direction
bool
HandleUpstream(const llarp_buffer_t& X, const TunnelNonce& Y,
AbstractRouter* r) override;
// handle data in downstream direction
bool
HandleDownstream(const llarp_buffer_t& X, const TunnelNonce& Y,
AbstractRouter* r) override;
};
using TransitHop_ptr = std::shared_ptr< TransitHop >;
inline std::ostream&
operator<<(std::ostream& out, const TransitHop& h)
{
return h.print(out, -1, -1);
}
/// configuration for a single hop when building a path
struct PathHopConfig
{
/// path id
PathID_t txID, rxID;
// router contact of router
RouterContact rc;
// temp public encryption key
SecretKey commkey;
/// shared secret at this hop
SharedSecret shared;
/// hash of shared secret used for nonce mutation
ShortHash nonceXOR;
/// next hop's router id
RouterID upstream;
/// nonce for key exchange
TunnelNonce nonce;
// lifetime
llarp_time_t lifetime = default_lifetime;
~PathHopConfig();
PathHopConfig();
util::StatusObject
ExtractStatus() const;
bool
operator<(const PathHopConfig& other) const
{
return std::tie(txID, rxID, rc, upstream, lifetime)
< std::tie(other.txID, other.rxID, other.rc, other.upstream,
other.lifetime);
}
};
/// A path we made
struct Path : public IHopHandler,
public routing::IMessageHandler,
public std::enable_shared_from_this< Path >
{
using BuildResultHookFunc = std::function< void(Path_ptr) >;
using CheckForDeadFunc = std::function< bool(Path_ptr, llarp_time_t) >;
using DropHandlerFunc =
std::function< bool(Path_ptr, const PathID_t&, uint64_t) >;
using HopList = std::vector< PathHopConfig >;
using DataHandlerFunc =
std::function< bool(Path_ptr, const service::ProtocolFrame&) >;
using ExitUpdatedFunc = std::function< bool(Path_ptr) >;
using ExitClosedFunc = std::function< bool(Path_ptr) >;
using ExitTrafficHandlerFunc =
std::function< bool(Path_ptr, const llarp_buffer_t&, uint64_t) >;
/// (path, backoff) backoff is 0 on success
using ObtainedExitHandler = std::function< bool(Path_ptr, llarp_time_t) >;
HopList hops;
PathSet* const m_PathSet;
service::Introduction intro;
llarp_time_t buildStarted;
Path(const std::vector< RouterContact >& routers, PathSet* parent,
PathRole startingRoles);
util::StatusObject
ExtractStatus() const;
PathRole
Role() const
{
return _role;
}
bool
operator<(const Path& other) const
{
return hops < other.hops;
}
void
MarkActive(llarp_time_t now)
{
m_LastRecvMessage = std::max(now, m_LastRecvMessage);
}
/// return true if ALL of the specified roles are supported
bool
SupportsAllRoles(PathRole roles) const
{
return (_role & roles) == roles;
}
/// return true if ANY of the specified roles are supported
bool
SupportsAnyRoles(PathRole roles) const
{
return roles == ePathRoleAny || (_role | roles) != 0;
}
/// clear role bits
void
ClearRoles(PathRole roles)
{
_role &= ~roles;
}
PathStatus
Status() const
{
return _status;
}
std::string
HopsString() const;
llarp_time_t
LastRemoteActivityAt() const override
{
return m_LastRecvMessage;
}
void
SetBuildResultHook(BuildResultHookFunc func);
void
SetExitTrafficHandler(ExitTrafficHandlerFunc handler)
{
m_ExitTrafficHandler = handler;
}
void
SetCloseExitFunc(ExitClosedFunc handler)
{
m_ExitClosed = handler;
}
void
SetUpdateExitFunc(ExitUpdatedFunc handler)
{
m_ExitUpdated = handler;
}
void
SetDataHandler(DataHandlerFunc func)
{
m_DataHandler = func;
}
void
SetDropHandler(DropHandlerFunc func)
{
m_DropHandler = func;
}
void
SetDeadChecker(CheckForDeadFunc func)
{
m_CheckForDead = func;
}
void
EnterState(PathStatus st, llarp_time_t now);
llarp_time_t
ExpireTime() const
{
return buildStarted + hops[0].lifetime;
}
bool
ExpiresSoon(llarp_time_t now, llarp_time_t dlt = 5000) const override
{
return now >= (ExpireTime() - dlt);
}
bool
Expired(llarp_time_t now) const override;
/// build a new path on the same set of hops as us
/// regenerates keys
void
Rebuild();
void
Tick(llarp_time_t now, AbstractRouter* r);
bool
SendRoutingMessage(const routing::IMessage& msg,
AbstractRouter* r) override;
bool
HandleObtainExitMessage(const routing::ObtainExitMessage& msg,
AbstractRouter* r) override;
bool
HandleUpdateExitVerifyMessage(const routing::UpdateExitVerifyMessage& msg,
AbstractRouter* r) override;
bool
HandleTransferTrafficMessage(const routing::TransferTrafficMessage& msg,
AbstractRouter* r) override;
bool
HandleUpdateExitMessage(const routing::UpdateExitMessage& msg,
AbstractRouter* r) override;
bool
HandleCloseExitMessage(const routing::CloseExitMessage& msg,
AbstractRouter* r) override;
bool
HandleGrantExitMessage(const routing::GrantExitMessage& msg,
AbstractRouter* r) override;
bool
HandleRejectExitMessage(const routing::RejectExitMessage& msg,
AbstractRouter* r) override;
bool
HandleDataDiscardMessage(const routing::DataDiscardMessage& msg,
AbstractRouter* r) override;
bool
HandlePathConfirmMessage(const routing::PathConfirmMessage& msg,
AbstractRouter* r) override;
bool
HandlePathLatencyMessage(const routing::PathLatencyMessage& msg,
AbstractRouter* r) override;
bool
HandlePathTransferMessage(const routing::PathTransferMessage& msg,
AbstractRouter* r) override;
bool
HandleHiddenServiceFrame(const service::ProtocolFrame& frame) override;
bool
HandleGotIntroMessage(const dht::GotIntroMessage& msg);
bool
HandleDHTMessage(const dht::IMessage& msg, AbstractRouter* r) override;
bool
HandleRoutingMessage(const llarp_buffer_t& buf, AbstractRouter* r);
// handle data in upstream direction
bool
HandleUpstream(const llarp_buffer_t& X, const TunnelNonce& Y,
AbstractRouter* r) override;
// handle data in downstream direction
bool
HandleDownstream(const llarp_buffer_t& X, const TunnelNonce& Y,
AbstractRouter* r) override;
bool
IsReady() const;
// Is this deprecated?
// nope not deprecated :^DDDD
PathID_t
TXID() const;
RouterID
Endpoint() const;
PubKey
EndpointPubKey() const;
bool
IsEndpoint(const RouterID& router, const PathID_t& path) const;
PathID_t
RXID() const;
RouterID
Upstream() const;
std::string
Name() const;
void
AddObtainExitHandler(ObtainedExitHandler handler)
{
m_ObtainedExitHooks.push_back(handler);
}
bool
SendExitRequest(const routing::ObtainExitMessage& msg, AbstractRouter* r);
bool
SendExitClose(const routing::CloseExitMessage& msg, AbstractRouter* r);
private:
/// call obtained exit hooks
bool
InformExitResult(llarp_time_t b);
BuildResultHookFunc m_BuiltHook;
DataHandlerFunc m_DataHandler;
DropHandlerFunc m_DropHandler;
CheckForDeadFunc m_CheckForDead;
ExitUpdatedFunc m_ExitUpdated;
ExitClosedFunc m_ExitClosed;
ExitTrafficHandlerFunc m_ExitTrafficHandler;
std::vector< ObtainedExitHandler > m_ObtainedExitHooks;
llarp_time_t m_LastRecvMessage = 0;
llarp_time_t m_LastLatencyTestTime = 0;
uint64_t m_LastLatencyTestID = 0;
uint64_t m_UpdateExitTX = 0;
uint64_t m_CloseExitTX = 0;
uint64_t m_ExitObtainTX = 0;
PathStatus _status;
PathRole _role;
};
enum PathBuildStatus
{
ePathBuildSuccess,
ePathBuildTimeout,
ePathBuildReject
};
struct PathContext
{
PathContext(AbstractRouter* router);
~PathContext();
/// called from router tick function
void
ExpirePaths(llarp_time_t now);
void
AllowTransit();
void
RejectTransit();
bool
AllowingTransit() const;
bool
HasTransitHop(const TransitHopInfo& info);
bool
HandleRelayCommit(const LR_CommitMessage& msg);
void
PutTransitHop(std::shared_ptr< TransitHop > hop);
HopHandler_ptr
GetByUpstream(const RouterID& id, const PathID_t& path);
bool
TransitHopPreviousIsRouter(const PathID_t& path, const RouterID& r);
HopHandler_ptr
GetPathForTransfer(const PathID_t& topath);
HopHandler_ptr
GetByDownstream(const RouterID& id, const PathID_t& path);
PathSet_ptr
GetLocalPathSet(const PathID_t& id);
routing::MessageHandler_ptr
GetHandler(const PathID_t& id);
using EndpointPathPtrSet = std::set< Path_ptr, ComparePtr< Path_ptr > >;
/// get a set of all paths that we own who's endpoint is r
EndpointPathPtrSet
FindOwnedPathsWithEndpoint(const RouterID& r);
bool
ForwardLRCM(const RouterID& nextHop,
const std::array< EncryptedFrame, 8 >& frames);
bool
HopIsUs(const RouterID& k) const;
bool
HandleLRUM(const RelayUpstreamMessage& msg);
bool
HandleLRDM(const RelayDownstreamMessage& msg);
void
AddOwnPath(PathSet_ptr set, Path_ptr p);
void
RemovePathSet(PathSet_ptr set);
using TransitHopsMap_t = std::multimap< PathID_t, TransitHop_ptr >;
struct SyncTransitMap_t
{
util::Mutex first; // protects second
TransitHopsMap_t second GUARDED_BY(first);
void
ForEach(std::function< void(const TransitHop_ptr&) > visit)
{
util::Lock lock(&first);
for(const auto& item : second)
visit(item.second);
}
};
// maps path id -> pathset owner of path
using OwnedPathsMap_t = std::map< PathID_t, PathSet_ptr >;
struct SyncOwnedPathsMap_t
{
util::Mutex first; // protects second
OwnedPathsMap_t second GUARDED_BY(first);
void
ForEach(std::function< void(const PathSet_ptr&) > visit)
{
util::Lock lock(&first);
for(const auto& item : second)
visit(item.second);
}
};
llarp_threadpool*
Worker();
llarp::Crypto*
crypto();
Logic*
logic();
AbstractRouter*
Router();
const SecretKey&
EncryptionSecretKey();
const byte_t*
OurRouterID() const;
private:
AbstractRouter* m_Router;
SyncTransitMap_t m_TransitPaths;
SyncOwnedPathsMap_t m_OurPaths;
bool m_AllowTransit;
};
} // namespace path
} // namespace llarp
#endif