|
|
|
#include <llarp/link/utp.hpp>
|
|
|
|
#include "router.hpp"
|
|
|
|
#include <llarp/messages/link_intro.hpp>
|
|
|
|
#include <llarp/messages/discard.hpp>
|
|
|
|
#include <llarp/buffer.hpp>
|
|
|
|
#include <llarp/endian.h>
|
|
|
|
#include <utp.h>
|
|
|
|
#include <cassert>
|
|
|
|
#include <tuple>
|
|
|
|
#include <deque>
|
|
|
|
|
|
|
|
#ifdef __linux__
|
|
|
|
#include <linux/errqueue.h>
|
|
|
|
#include <netinet/ip_icmp.h>
|
|
|
|
#endif
|
|
|
|
|
|
|
|
namespace llarp
|
|
|
|
{
|
|
|
|
namespace utp
|
|
|
|
{
|
|
|
|
constexpr size_t FragmentHashSize = 32;
|
|
|
|
constexpr size_t FragmentNonceSize = 24;
|
|
|
|
constexpr size_t FragmentOverheadSize =
|
|
|
|
FragmentHashSize + FragmentNonceSize;
|
|
|
|
constexpr size_t FragmentBodyPayloadSize = 1024;
|
|
|
|
constexpr size_t FragmentBodyOverhead = sizeof(uint32_t) * 2;
|
|
|
|
constexpr size_t FragmentBodySize =
|
|
|
|
FragmentBodyOverhead + FragmentBodyPayloadSize;
|
|
|
|
|
|
|
|
constexpr size_t FragmentBufferSize =
|
|
|
|
FragmentOverheadSize + FragmentBodySize;
|
|
|
|
typedef llarp::AlignedBuffer< FragmentBufferSize > FragmentBuffer;
|
|
|
|
|
|
|
|
typedef llarp::AlignedBuffer< MAX_LINK_MSG_SIZE > MessageBuffer;
|
|
|
|
|
|
|
|
struct LinkLayer;
|
|
|
|
|
|
|
|
struct BaseSession : public ILinkSession
|
|
|
|
{
|
|
|
|
RouterContact remoteRC;
|
|
|
|
utp_socket* sock;
|
|
|
|
LinkLayer* parent;
|
|
|
|
bool gotLIM;
|
|
|
|
PubKey remoteTransportPubKey;
|
|
|
|
Addr remoteAddr;
|
|
|
|
SharedSecret sessionKey;
|
|
|
|
llarp_time_t lastActive;
|
|
|
|
const static llarp_time_t sessionTimeout = 30 * 1000;
|
|
|
|
|
|
|
|
std::deque< FragmentBuffer > sendq;
|
|
|
|
size_t sendBufOffset;
|
|
|
|
|
|
|
|
FragmentBuffer recvBuf;
|
|
|
|
size_t recvBufOffset;
|
|
|
|
MessageBuffer recvMsg;
|
|
|
|
size_t recvMsgOffset;
|
|
|
|
bool stalled = false;
|
|
|
|
|
|
|
|
void
|
|
|
|
Alive();
|
|
|
|
|
|
|
|
/// base
|
|
|
|
BaseSession(LinkLayer* p);
|
|
|
|
|
|
|
|
/// outbound
|
|
|
|
BaseSession(LinkLayer* p, utp_socket* s, const RouterContact& rc,
|
|
|
|
const AddressInfo& addr);
|
|
|
|
|
|
|
|
/// inbound
|
|
|
|
BaseSession(LinkLayer* p, utp_socket* s, const Addr& remote);
|
|
|
|
|
|
|
|
enum State
|
|
|
|
{
|
|
|
|
eInitial,
|
|
|
|
eConnecting,
|
|
|
|
eLinkEstablished, // when utp connection is established
|
|
|
|
eCryptoHandshake, // crypto handshake initiated
|
|
|
|
eSessionReady, // session is ready
|
|
|
|
eClose // utp connection is closed
|
|
|
|
};
|
|
|
|
|
|
|
|
llarp_router*
|
|
|
|
Router();
|
|
|
|
|
|
|
|
State state;
|
|
|
|
|
|
|
|
void
|
|
|
|
OnLinkEstablished(LinkLayer* p)
|
|
|
|
{
|
|
|
|
parent = p;
|
|
|
|
EnterState(eLinkEstablished);
|
|
|
|
llarp::LogDebug("link established with ", remoteAddr);
|
|
|
|
}
|
|
|
|
|
|
|
|
void
|
|
|
|
EnterState(State st);
|
|
|
|
|
|
|
|
BaseSession();
|
|
|
|
~BaseSession();
|
|
|
|
|
|
|
|
void
|
|
|
|
PumpWrite()
|
|
|
|
{
|
|
|
|
while(sendq.size() > 0 && !stalled)
|
|
|
|
{
|
|
|
|
ssize_t expect = FragmentBufferSize - sendBufOffset;
|
|
|
|
ssize_t s = write_ll(sendq.front().data() + sendBufOffset, expect);
|
|
|
|
if(s != expect)
|
|
|
|
{
|
|
|
|
llarp::LogDebug("stalled at offset=", sendBufOffset, " sz=", s,
|
|
|
|
" to ", remoteAddr);
|
|
|
|
sendBufOffset += s;
|
|
|
|
stalled = true;
|
|
|
|
}
|
|
|
|
else
|
|
|
|
{
|
|
|
|
sendBufOffset = 0;
|
|
|
|
sendq.pop_front();
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
ssize_t
|
|
|
|
write_ll(byte_t* buf, size_t sz)
|
|
|
|
{
|
|
|
|
if(sock == nullptr)
|
|
|
|
{
|
|
|
|
llarp::LogWarn("write_ll failed: no socket");
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
ssize_t s = utp_write(sock, buf, sz);
|
|
|
|
llarp::LogDebug("write_ll ", s, " of ", sz, " bytes to ", remoteAddr);
|
|
|
|
return s;
|
|
|
|
}
|
|
|
|
|
|
|
|
bool
|
|
|
|
VerifyThenDecrypt(byte_t* buf);
|
|
|
|
|
|
|
|
void
|
|
|
|
EncryptThenHash(const byte_t* ptr, uint32_t sz, bool isLastFragment);
|
|
|
|
|
|
|
|
bool
|
|
|
|
QueueWriteBuffers(llarp_buffer_t buf)
|
|
|
|
{
|
|
|
|
llarp::LogDebug("write ", buf.sz, " bytes to ", remoteAddr);
|
|
|
|
lastActive = llarp_time_now_ms();
|
|
|
|
size_t sz = buf.sz;
|
|
|
|
byte_t* ptr = buf.base;
|
|
|
|
while(sz)
|
|
|
|
{
|
|
|
|
uint32_t s = std::min(FragmentBodyPayloadSize, sz);
|
|
|
|
EncryptThenHash(ptr, s, ((sz - s) == 0));
|
|
|
|
ptr += s;
|
|
|
|
sz -= s;
|
|
|
|
}
|
|
|
|
return true;
|
|
|
|
}
|
|
|
|
|
|
|
|
void
|
|
|
|
Connect()
|
|
|
|
{
|
|
|
|
utp_connect(sock, remoteAddr, remoteAddr.SockLen());
|
|
|
|
EnterState(eConnecting);
|
|
|
|
}
|
|
|
|
|
|
|
|
void
|
|
|
|
OutboundLinkEstablished(LinkLayer* p)
|
|
|
|
{
|
|
|
|
OnLinkEstablished(p);
|
|
|
|
OutboundHandshake();
|
|
|
|
}
|
|
|
|
|
|
|
|
// send first message
|
|
|
|
void
|
|
|
|
OutboundHandshake();
|
|
|
|
|
|
|
|
// mix keys
|
|
|
|
bool
|
|
|
|
DoKeyExchange(llarp_transport_dh_func dh, const KeyExchangeNonce& n,
|
|
|
|
const PubKey& other, const SecretKey& secret)
|
|
|
|
{
|
|
|
|
ShortHash t_h;
|
|
|
|
AlignedBuffer< 64 > tmp;
|
|
|
|
memcpy(tmp.data(), sessionKey, sessionKey.size());
|
|
|
|
memcpy(tmp.data() + sessionKey.size(), n, n.size());
|
|
|
|
// t_h = HS(K + L.n)
|
|
|
|
if(!Router()->crypto.shorthash(t_h, ConstBuffer(tmp)))
|
|
|
|
{
|
|
|
|
llarp::LogError("failed to mix key to ", remoteAddr);
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
|
|
|
|
// K = TKE(a.p, B_a.e, sk, t_h)
|
|
|
|
if(!dh(sessionKey, other, secret, t_h))
|
|
|
|
{
|
|
|
|
llarp::LogError("key exchange with ", other, " failed");
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
llarp::LogDebug("keys mixed with session to ", remoteAddr);
|
|
|
|
return true;
|
|
|
|
}
|
|
|
|
|
|
|
|
void
|
|
|
|
TickImpl(llarp_time_t now)
|
|
|
|
{
|
|
|
|
}
|
|
|
|
|
|
|
|
void
|
|
|
|
Close();
|
|
|
|
|
|
|
|
bool
|
|
|
|
Recv(const void* buf, size_t sz)
|
|
|
|
{
|
|
|
|
Alive();
|
|
|
|
byte_t* ptr = (byte_t*)buf;
|
|
|
|
llarp::LogDebug("utp read ", sz, " from ", remoteAddr);
|
|
|
|
size_t s = sz;
|
|
|
|
// process leftovers
|
|
|
|
if(recvBufOffset)
|
|
|
|
{
|
|
|
|
auto left = FragmentBufferSize - recvBufOffset;
|
|
|
|
if(s >= left)
|
|
|
|
{
|
|
|
|
// yes it fills it
|
|
|
|
llarp::LogDebug("process leftovers, offset=", recvBufOffset,
|
|
|
|
" sz=", s, " left=", left);
|
|
|
|
memcpy(recvBuf.data() + recvBufOffset, ptr, left);
|
|
|
|
s -= left;
|
|
|
|
recvBufOffset = 0;
|
|
|
|
ptr += left;
|
|
|
|
if(!VerifyThenDecrypt(recvBuf.data()))
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
// process full fragments
|
|
|
|
while(s >= FragmentBufferSize)
|
|
|
|
{
|
|
|
|
recvBufOffset = 0;
|
|
|
|
llarp::LogDebug("process full sz=", s);
|
|
|
|
if(!VerifyThenDecrypt(ptr))
|
|
|
|
return false;
|
|
|
|
ptr += FragmentBufferSize;
|
|
|
|
s -= FragmentBufferSize;
|
|
|
|
}
|
|
|
|
if(s)
|
|
|
|
{
|
|
|
|
// hold onto leftovers
|
|
|
|
llarp::LogDebug("leftovers sz=", s);
|
|
|
|
memcpy(recvBuf.data() + recvBufOffset, ptr, s);
|
|
|
|
recvBufOffset += s;
|
|
|
|
}
|
|
|
|
return true;
|
|
|
|
}
|
|
|
|
|
|
|
|
bool
|
|
|
|
InboundLIM(const LinkIntroMessage* msg);
|
|
|
|
|
|
|
|
bool
|
|
|
|
OutboundLIM(const LinkIntroMessage* msg);
|
|
|
|
|
|
|
|
bool
|
|
|
|
IsTimedOut(llarp_time_t now) const
|
|
|
|
{
|
|
|
|
if(now < lastActive)
|
|
|
|
return false;
|
|
|
|
auto dlt = now - lastActive;
|
|
|
|
if(dlt >= sessionTimeout)
|
|
|
|
{
|
|
|
|
llarp::LogDebug("session timeout reached for ", remoteAddr);
|
|
|
|
return true;
|
|
|
|
}
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
|
|
|
|
const PubKey&
|
|
|
|
RemotePubKey() const
|
|
|
|
{
|
|
|
|
return remoteRC.pubkey;
|
|
|
|
}
|
|
|
|
|
|
|
|
const Addr&
|
|
|
|
RemoteEndpoint() const
|
|
|
|
{
|
|
|
|
return remoteAddr;
|
|
|
|
}
|
|
|
|
|
|
|
|
void
|
|
|
|
MarkEstablished();
|
|
|
|
}; // namespace utp
|
|
|
|
|
|
|
|
struct LinkLayer : public ILinkLayer
|
|
|
|
{
|
|
|
|
utp_context* _utp_ctx = nullptr;
|
|
|
|
llarp_router* router = nullptr;
|
|
|
|
static uint64
|
|
|
|
OnRead(utp_callback_arguments* arg);
|
|
|
|
|
|
|
|
static uint64
|
|
|
|
SendTo(utp_callback_arguments* arg)
|
|
|
|
{
|
|
|
|
LinkLayer* l =
|
|
|
|
static_cast< LinkLayer* >(utp_context_get_userdata(arg->context));
|
|
|
|
llarp::LogDebug("utp_sendto ", Addr(*arg->address), " ", arg->len,
|
|
|
|
" bytes");
|
|
|
|
if(sendto(l->m_udp.fd, arg->buf, arg->len, arg->flags, arg->address,
|
|
|
|
arg->address_len)
|
|
|
|
== -1)
|
|
|
|
{
|
|
|
|
llarp::LogError("sendto failed: ", strerror(errno));
|
|
|
|
}
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
static uint64
|
|
|
|
OnError(utp_callback_arguments* arg)
|
|
|
|
{
|
|
|
|
llarp::LogError(utp_error_code_names[arg->error_code]);
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
static uint64
|
|
|
|
OnStateChange(utp_callback_arguments*);
|
|
|
|
|
|
|
|
static uint64
|
|
|
|
OnAccept(utp_callback_arguments*);
|
|
|
|
|
|
|
|
static uint64
|
|
|
|
OnLog(utp_callback_arguments* arg)
|
|
|
|
{
|
|
|
|
llarp::LogDebug(arg->buf);
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
LinkLayer(llarp_router* r) : ILinkLayer()
|
|
|
|
{
|
|
|
|
router = r;
|
|
|
|
_utp_ctx = utp_init(2);
|
|
|
|
utp_context_set_userdata(_utp_ctx, this);
|
|
|
|
utp_set_callback(_utp_ctx, UTP_SENDTO, &LinkLayer::SendTo);
|
|
|
|
utp_set_callback(_utp_ctx, UTP_ON_ACCEPT, &LinkLayer::OnAccept);
|
|
|
|
utp_set_callback(_utp_ctx, UTP_ON_STATE_CHANGE,
|
|
|
|
&LinkLayer::OnStateChange);
|
|
|
|
utp_set_callback(_utp_ctx, UTP_ON_READ, &LinkLayer::OnRead);
|
|
|
|
utp_set_callback(_utp_ctx, UTP_ON_ERROR, &LinkLayer::OnError);
|
|
|
|
utp_set_callback(_utp_ctx, UTP_LOG, &LinkLayer::OnLog);
|
|
|
|
utp_context_set_option(_utp_ctx, UTP_LOG_NORMAL, 1);
|
|
|
|
utp_context_set_option(_utp_ctx, UTP_LOG_MTU, 1);
|
|
|
|
utp_context_set_option(_utp_ctx, UTP_LOG_DEBUG, 1);
|
|
|
|
utp_context_set_option(_utp_ctx, UTP_SNDBUF, MAX_LINK_MSG_SIZE * 16);
|
|
|
|
utp_context_set_option(_utp_ctx, UTP_RCVBUF, MAX_LINK_MSG_SIZE * 64);
|
|
|
|
}
|
|
|
|
|
|
|
|
~LinkLayer()
|
|
|
|
{
|
|
|
|
utp_destroy(_utp_ctx);
|
|
|
|
}
|
|
|
|
|
|
|
|
uint16_t
|
|
|
|
Rank() const
|
|
|
|
{
|
|
|
|
return 1;
|
|
|
|
}
|
|
|
|
|
|
|
|
void
|
|
|
|
RecvFrom(const Addr& from, const void* buf, size_t sz)
|
|
|
|
{
|
|
|
|
utp_process_udp(_utp_ctx, (const byte_t*)buf, sz, from, from.SockLen());
|
|
|
|
}
|
|
|
|
|
|
|
|
#ifdef __linux__
|
|
|
|
void
|
|
|
|
ProcessICMP()
|
|
|
|
{
|
|
|
|
do
|
|
|
|
{
|
|
|
|
byte_t vec_buf[4096], ancillary_buf[4096];
|
|
|
|
struct iovec iov = {vec_buf, sizeof(vec_buf)};
|
|
|
|
struct sockaddr_in remote;
|
|
|
|
struct msghdr msg;
|
|
|
|
ssize_t len;
|
|
|
|
struct cmsghdr* cmsg;
|
|
|
|
struct sock_extended_err* e;
|
|
|
|
struct sockaddr* icmp_addr;
|
|
|
|
struct sockaddr_in* icmp_sin;
|
|
|
|
|
|
|
|
memset(&msg, 0, sizeof(msg));
|
|
|
|
|
|
|
|
msg.msg_name = &remote;
|
|
|
|
msg.msg_namelen = sizeof(remote);
|
|
|
|
msg.msg_iov = &iov;
|
|
|
|
msg.msg_iovlen = 1;
|
|
|
|
msg.msg_flags = 0;
|
|
|
|
msg.msg_control = ancillary_buf;
|
|
|
|
msg.msg_controllen = sizeof(ancillary_buf);
|
|
|
|
|
|
|
|
len = recvmsg(m_udp.fd, &msg, MSG_ERRQUEUE | MSG_DONTWAIT);
|
|
|
|
if(len < 0)
|
|
|
|
{
|
|
|
|
if(errno == EAGAIN || errno == EWOULDBLOCK)
|
|
|
|
errno = 0;
|
|
|
|
else
|
|
|
|
llarp::LogError("failed to read icmp for utp ", strerror(errno));
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
|
|
|
|
for(cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg))
|
|
|
|
{
|
|
|
|
if(cmsg->cmsg_type != IP_RECVERR)
|
|
|
|
{
|
|
|
|
continue;
|
|
|
|
}
|
|
|
|
if(cmsg->cmsg_level != SOL_IP)
|
|
|
|
{
|
|
|
|
continue;
|
|
|
|
}
|
|
|
|
e = (struct sock_extended_err*)CMSG_DATA(cmsg);
|
|
|
|
if(!e)
|
|
|
|
continue;
|
|
|
|
if(e->ee_origin != SO_EE_ORIGIN_ICMP)
|
|
|
|
{
|
|
|
|
continue;
|
|
|
|
}
|
|
|
|
icmp_addr = (struct sockaddr*)SO_EE_OFFENDER(e);
|
|
|
|
icmp_sin = (struct sockaddr_in*)icmp_addr;
|
|
|
|
if(icmp_sin->sin_port != 0)
|
|
|
|
{
|
|
|
|
continue;
|
|
|
|
}
|
|
|
|
if(e->ee_type == 3 && e->ee_code == 4)
|
|
|
|
{
|
|
|
|
utp_process_icmp_fragmentation(_utp_ctx, vec_buf, len,
|
|
|
|
(struct sockaddr*)&remote,
|
|
|
|
sizeof(remote), e->ee_info);
|
|
|
|
}
|
|
|
|
else
|
|
|
|
{
|
|
|
|
utp_process_icmp_error(_utp_ctx, vec_buf, len,
|
|
|
|
(struct sockaddr*)&remote, sizeof(remote));
|
|
|
|
}
|
|
|
|
}
|
|
|
|
} while(true);
|
|
|
|
}
|
|
|
|
#endif
|
|
|
|
|
|
|
|
void
|
|
|
|
Pump()
|
|
|
|
{
|
|
|
|
utp_issue_deferred_acks(_utp_ctx);
|
|
|
|
#ifdef __linux__
|
|
|
|
ProcessICMP();
|
|
|
|
#endif
|
|
|
|
std::set< PubKey > sessions;
|
|
|
|
{
|
|
|
|
Lock l(m_AuthedLinksMutex);
|
|
|
|
auto itr = m_AuthedLinks.begin();
|
|
|
|
while(itr != m_AuthedLinks.end())
|
|
|
|
{
|
|
|
|
sessions.insert(itr->first);
|
|
|
|
++itr;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
ILinkLayer::Pump();
|
|
|
|
{
|
|
|
|
Lock l(m_AuthedLinksMutex);
|
|
|
|
for(const auto& pk : sessions)
|
|
|
|
{
|
|
|
|
if(m_AuthedLinks.find(pk) == m_AuthedLinks.end())
|
|
|
|
{
|
|
|
|
// all sessions were removed
|
|
|
|
router->SessionClosed(pk);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
void
|
|
|
|
Stop()
|
|
|
|
{
|
|
|
|
}
|
|
|
|
|
|
|
|
llarp_router*
|
|
|
|
GetRouter();
|
|
|
|
|
|
|
|
bool
|
|
|
|
KeyGen(SecretKey& k)
|
|
|
|
{
|
|
|
|
router->crypto.encryption_keygen(k);
|
|
|
|
return true;
|
|
|
|
}
|
|
|
|
|
|
|
|
void
|
|
|
|
Tick(llarp_time_t now)
|
|
|
|
{
|
|
|
|
utp_check_timeouts(_utp_ctx);
|
|
|
|
ILinkLayer::Tick(now);
|
|
|
|
}
|
|
|
|
|
|
|
|
ILinkSession*
|
|
|
|
NewOutboundSession(const RouterContact& rc, const AddressInfo& addr);
|
|
|
|
|
|
|
|
utp_socket*
|
|
|
|
NewSocket()
|
|
|
|
{
|
|
|
|
return utp_create_socket(_utp_ctx);
|
|
|
|
}
|
|
|
|
|
|
|
|
const char*
|
|
|
|
Name() const
|
|
|
|
{
|
|
|
|
return "utp";
|
|
|
|
}
|
|
|
|
};
|
|
|
|
|
|
|
|
std::unique_ptr< ILinkLayer >
|
|
|
|
NewServer(llarp_router* r)
|
|
|
|
{
|
|
|
|
return std::unique_ptr< LinkLayer >(new LinkLayer(r));
|
|
|
|
}
|
|
|
|
|
|
|
|
BaseSession::BaseSession(LinkLayer* p)
|
|
|
|
{
|
|
|
|
parent = p;
|
|
|
|
remoteTransportPubKey.Zero();
|
|
|
|
recvMsgOffset = 0;
|
|
|
|
|
|
|
|
SendKeepAlive = [&]() -> bool {
|
|
|
|
/*
|
|
|
|
if(sendq.size() == 0 && state == eSessionReady)
|
|
|
|
{
|
|
|
|
DiscardMessage msg;
|
|
|
|
byte_t tmp[128] = {0};
|
|
|
|
auto buf = llarp::StackBuffer< decltype(tmp) >(tmp);
|
|
|
|
if(!msg.BEncode(&buf))
|
|
|
|
return false;
|
|
|
|
buf.sz = buf.cur - buf.base;
|
|
|
|
buf.cur = buf.base;
|
|
|
|
if(!this->QueueWriteBuffers(buf))
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
*/
|
|
|
|
return true;
|
|
|
|
};
|
|
|
|
gotLIM = false;
|
|
|
|
sendBufOffset = 0;
|
|
|
|
recvBufOffset = 0;
|
|
|
|
TimedOut = [&](llarp_time_t now) -> bool {
|
|
|
|
return this->IsTimedOut(now) || this->state == eClose;
|
|
|
|
};
|
|
|
|
GetPubKey = std::bind(&BaseSession::RemotePubKey, this);
|
|
|
|
lastActive = llarp_time_now_ms();
|
|
|
|
Pump = std::bind(&BaseSession::PumpWrite, this);
|
|
|
|
Tick = std::bind(&BaseSession::TickImpl, this, std::placeholders::_1);
|
|
|
|
SendMessageBuffer = std::bind(&BaseSession::QueueWriteBuffers, this,
|
|
|
|
std::placeholders::_1);
|
|
|
|
|
|
|
|
IsEstablished = [=]() {
|
|
|
|
return this->state == eSessionReady || this->state == eLinkEstablished;
|
|
|
|
};
|
|
|
|
|
|
|
|
SendClose = std::bind(&BaseSession::Close, this);
|
|
|
|
GetRemoteEndpoint = std::bind(&BaseSession::RemoteEndpoint, this);
|
|
|
|
}
|
|
|
|
|
|
|
|
BaseSession::BaseSession(LinkLayer* p, utp_socket* s,
|
|
|
|
const RouterContact& rc, const AddressInfo& addr)
|
|
|
|
: BaseSession(p)
|
|
|
|
{
|
|
|
|
remoteRC.Clear();
|
|
|
|
remoteTransportPubKey = addr.pubkey;
|
|
|
|
remoteRC = rc;
|
|
|
|
sock = s;
|
|
|
|
assert(utp_set_userdata(sock, this) == this);
|
|
|
|
assert(s == sock);
|
|
|
|
remoteAddr = addr;
|
|
|
|
Start = std::bind(&BaseSession::Connect, this);
|
|
|
|
GotLIM =
|
|
|
|
std::bind(&BaseSession::OutboundLIM, this, std::placeholders::_1);
|
|
|
|
}
|
|
|
|
|
|
|
|
BaseSession::BaseSession(LinkLayer* p, utp_socket* s, const Addr& addr)
|
|
|
|
: BaseSession(p)
|
|
|
|
{
|
|
|
|
p->router->crypto.shorthash(sessionKey,
|
|
|
|
InitBuffer(p->router->pubkey(), PUBKEYSIZE));
|
|
|
|
remoteRC.Clear();
|
|
|
|
sock = s;
|
|
|
|
assert(s == sock);
|
|
|
|
assert(utp_set_userdata(sock, this) == this);
|
|
|
|
remoteAddr = addr;
|
|
|
|
Start = []() {};
|
|
|
|
GotLIM = std::bind(&BaseSession::InboundLIM, this, std::placeholders::_1);
|
|
|
|
}
|
|
|
|
|
|
|
|
bool
|
|
|
|
BaseSession::InboundLIM(const LinkIntroMessage* msg)
|
|
|
|
{
|
|
|
|
if(gotLIM && remoteRC.pubkey != msg->rc.pubkey)
|
|
|
|
{
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
remoteRC = msg->rc;
|
|
|
|
gotLIM = true;
|
|
|
|
if(!DoKeyExchange(Router()->crypto.transport_dh_server, msg->N,
|
|
|
|
remoteRC.enckey, parent->TransportSecretKey()))
|
|
|
|
return false;
|
|
|
|
EnterState(eSessionReady);
|
|
|
|
return true;
|
|
|
|
}
|
|
|
|
|
|
|
|
bool
|
|
|
|
BaseSession::OutboundLIM(const LinkIntroMessage* msg)
|
|
|
|
{
|
|
|
|
if(gotLIM && remoteRC.pubkey != msg->rc.pubkey)
|
|
|
|
{
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
remoteRC = msg->rc;
|
|
|
|
gotLIM = true;
|
|
|
|
// TODO: update address info pubkey
|
|
|
|
return DoKeyExchange(Router()->crypto.transport_dh_client, msg->N,
|
|
|
|
remoteTransportPubKey, Router()->encryption);
|
|
|
|
}
|
|
|
|
|
|
|
|
void
|
|
|
|
BaseSession::OutboundHandshake()
|
|
|
|
{
|
|
|
|
// set session key
|
|
|
|
Router()->crypto.shorthash(sessionKey, ConstBuffer(remoteRC.pubkey));
|
|
|
|
|
|
|
|
byte_t tmp[LinkIntroMessage::MaxSize];
|
|
|
|
auto buf = StackBuffer< decltype(tmp) >(tmp);
|
|
|
|
// build our RC
|
|
|
|
LinkIntroMessage msg;
|
|
|
|
msg.rc = Router()->rc();
|
|
|
|
if(!msg.rc.VerifySignature(&Router()->crypto))
|
|
|
|
{
|
|
|
|
llarp::LogError("our RC is invalid? closing session to", remoteAddr);
|
|
|
|
Close();
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
msg.N.Randomize();
|
|
|
|
msg.P = DefaultLinkSessionLifetime;
|
|
|
|
if(!msg.Sign(&Router()->crypto, Router()->identity))
|
|
|
|
{
|
|
|
|
llarp::LogError("failed to sign LIM for outbound handshake to ",
|
|
|
|
remoteAddr);
|
|
|
|
Close();
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
// encode
|
|
|
|
if(!msg.BEncode(&buf))
|
|
|
|
{
|
|
|
|
llarp::LogError("failed to encode LIM for handshake to ", remoteAddr);
|
|
|
|
Close();
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
// rewind
|
|
|
|
buf.sz = buf.cur - buf.base;
|
|
|
|
buf.cur = buf.base;
|
|
|
|
// send
|
|
|
|
if(!SendMessageBuffer(buf))
|
|
|
|
{
|
|
|
|
llarp::LogError("failed to send handshake to ", remoteAddr);
|
|
|
|
Close();
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
// mix keys
|
|
|
|
if(!DoKeyExchange(Router()->crypto.transport_dh_client, msg.N,
|
|
|
|
remoteTransportPubKey, Router()->encryption))
|
|
|
|
{
|
|
|
|
llarp::LogError("failed to mix keys for outbound session to ",
|
|
|
|
remoteAddr);
|
|
|
|
Close();
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
EnterState(eSessionReady);
|
|
|
|
}
|
|
|
|
|
|
|
|
llarp_router*
|
|
|
|
BaseSession::Router()
|
|
|
|
{
|
|
|
|
return parent->router;
|
|
|
|
}
|
|
|
|
|
|
|
|
BaseSession::~BaseSession()
|
|
|
|
{
|
|
|
|
if(sock)
|
|
|
|
{
|
|
|
|
utp_set_userdata(sock, nullptr);
|
|
|
|
sock = nullptr;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
ILinkSession*
|
|
|
|
LinkLayer::NewOutboundSession(const RouterContact& rc,
|
|
|
|
const AddressInfo& addr)
|
|
|
|
{
|
|
|
|
return new BaseSession(this, utp_create_socket(_utp_ctx), rc, addr);
|
|
|
|
}
|
|
|
|
|
|
|
|
uint64
|
|
|
|
LinkLayer::OnRead(utp_callback_arguments* arg)
|
|
|
|
{
|
|
|
|
BaseSession* self =
|
|
|
|
static_cast< BaseSession* >(utp_get_userdata(arg->socket));
|
|
|
|
|
|
|
|
if(self)
|
|
|
|
{
|
|
|
|
if(self->state == BaseSession::eClose)
|
|
|
|
{
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
if(!self->Recv(arg->buf, arg->len))
|
|
|
|
{
|
|
|
|
llarp::LogDebug("recv fail for ", self->remoteAddr);
|
|
|
|
self->Close();
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
utp_read_drained(arg->socket);
|
|
|
|
}
|
|
|
|
else
|
|
|
|
{
|
|
|
|
llarp::LogWarn("utp_socket got data with no underlying session");
|
|
|
|
}
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
uint64
|
|
|
|
LinkLayer::OnStateChange(utp_callback_arguments* arg)
|
|
|
|
{
|
|
|
|
LinkLayer* l =
|
|
|
|
static_cast< LinkLayer* >(utp_context_get_userdata(arg->context));
|
|
|
|
BaseSession* session =
|
|
|
|
static_cast< BaseSession* >(utp_get_userdata(arg->socket));
|
|
|
|
if(session)
|
|
|
|
{
|
|
|
|
if(arg->state == UTP_STATE_CONNECT)
|
|
|
|
{
|
|
|
|
if(session->state == BaseSession::eClose)
|
|
|
|
{
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
session->OutboundLinkEstablished(l);
|
|
|
|
}
|
|
|
|
else if(arg->state == UTP_STATE_WRITABLE)
|
|
|
|
{
|
|
|
|
if(session->IsEstablished())
|
|
|
|
{
|
|
|
|
llarp::LogDebug("write resumed for ", session->remoteAddr);
|
|
|
|
session->stalled = false;
|
|
|
|
session->PumpWrite();
|
|
|
|
}
|
|
|
|
}
|
|
|
|
else if(arg->state == UTP_STATE_EOF)
|
|
|
|
{
|
|
|
|
llarp::LogDebug("got eof from ", session->remoteAddr);
|
|
|
|
session->Close();
|
|
|
|
}
|
|
|
|
}
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
uint64
|
|
|
|
LinkLayer::OnAccept(utp_callback_arguments* arg)
|
|
|
|
{
|
|
|
|
LinkLayer* self =
|
|
|
|
static_cast< LinkLayer* >(utp_context_get_userdata(arg->context));
|
|
|
|
Addr remote(*arg->address);
|
|
|
|
llarp::LogDebug("utp accepted from ", remote);
|
|
|
|
BaseSession* session = new BaseSession(self, arg->socket, remote);
|
|
|
|
self->PutSession(session);
|
|
|
|
session->OnLinkEstablished(self);
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
void
|
|
|
|
BaseSession::EncryptThenHash(const byte_t* ptr, uint32_t sz,
|
|
|
|
bool isLastFragment)
|
|
|
|
|
|
|
|
{
|
|
|
|
sendq.emplace_back();
|
|
|
|
auto& buf = sendq.back();
|
|
|
|
llarp::LogDebug("encrypt then hash ", sz, " bytes last=", isLastFragment);
|
|
|
|
buf.Randomize();
|
|
|
|
byte_t* nonce = buf.data() + FragmentHashSize;
|
|
|
|
byte_t* body = nonce + FragmentNonceSize;
|
|
|
|
byte_t* base = body;
|
|
|
|
if(isLastFragment)
|
|
|
|
htobe32buf(body, 0);
|
|
|
|
else
|
|
|
|
htobe32buf(body, 1);
|
|
|
|
body += sizeof(uint32_t);
|
|
|
|
htobe32buf(body, sz);
|
|
|
|
body += sizeof(uint32_t);
|
|
|
|
memcpy(body, ptr, sz);
|
|
|
|
|
|
|
|
auto payload =
|
|
|
|
InitBuffer(base, FragmentBufferSize - FragmentOverheadSize);
|
|
|
|
|
|
|
|
// encrypt
|
|
|
|
Router()->crypto.xchacha20(payload, sessionKey, nonce);
|
|
|
|
|
|
|
|
payload.base = nonce;
|
|
|
|
payload.cur = payload.base;
|
|
|
|
payload.sz = FragmentBufferSize - FragmentHashSize;
|
|
|
|
// key'd hash
|
|
|
|
Router()->crypto.hmac(buf.data(), payload, sessionKey);
|
|
|
|
}
|
|
|
|
|
|
|
|
void
|
|
|
|
BaseSession::EnterState(State st)
|
|
|
|
{
|
|
|
|
state = st;
|
|
|
|
if(st == eSessionReady)
|
|
|
|
{
|
|
|
|
parent->MapAddr(remoteRC.pubkey, this);
|
|
|
|
Router()->HandleLinkSessionEstablished(remoteRC);
|
|
|
|
}
|
|
|
|
Alive();
|
|
|
|
}
|
|
|
|
|
|
|
|
bool
|
|
|
|
BaseSession::VerifyThenDecrypt(byte_t* buf)
|
|
|
|
{
|
|
|
|
llarp::LogDebug("verify then decrypt ", remoteAddr);
|
|
|
|
ShortHash digest;
|
|
|
|
|
|
|
|
auto hbuf = InitBuffer(buf + FragmentHashSize,
|
|
|
|
FragmentBufferSize - FragmentHashSize);
|
|
|
|
if(!Router()->crypto.hmac(digest.data(), hbuf, sessionKey))
|
|
|
|
{
|
|
|
|
llarp::LogError("keyed hash failed");
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
ShortHash expected(buf);
|
|
|
|
if(expected != digest)
|
|
|
|
{
|
|
|
|
llarp::LogError("Message Integrity Failed: got ", digest, " from ",
|
|
|
|
remoteAddr, " instead of ", expected);
|
|
|
|
llarp::DumpBuffer(InitBuffer(buf, FragmentBufferSize));
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
|
|
|
|
auto body = InitBuffer(buf + FragmentOverheadSize,
|
|
|
|
FragmentBufferSize - FragmentOverheadSize);
|
|
|
|
|
|
|
|
Router()->crypto.xchacha20(body, sessionKey, buf + FragmentHashSize);
|
|
|
|
|
|
|
|
uint32_t upper, lower;
|
|
|
|
if(!(llarp_buffer_read_uint32(&body, &upper)
|
|
|
|
&& llarp_buffer_read_uint32(&body, &lower)))
|
|
|
|
return false;
|
|
|
|
bool fragmentEnd = upper == 0;
|
|
|
|
llarp::LogDebug("fragment size ", lower, " from ", remoteAddr);
|
|
|
|
if(lower + recvMsgOffset > recvMsg.size())
|
|
|
|
{
|
|
|
|
llarp::LogError("Fragment too big: ", lower, " bytes");
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
memcpy(recvMsg.data() + recvMsgOffset, body.cur, lower);
|
|
|
|
recvMsgOffset += lower;
|
|
|
|
if(fragmentEnd)
|
|
|
|
{
|
|
|
|
// got a message
|
|
|
|
llarp::LogDebug("end of message from ", remoteAddr);
|
|
|
|
auto mbuf = InitBuffer(recvMsg.data(), recvMsgOffset);
|
|
|
|
if(!Router()->HandleRecvLinkMessageBuffer(this, mbuf))
|
|
|
|
{
|
|
|
|
llarp::LogWarn("failed to handle message from ", remoteAddr);
|
|
|
|
llarp::DumpBuffer(mbuf);
|
|
|
|
}
|
|
|
|
recvMsgOffset = 0;
|
|
|
|
}
|
|
|
|
return true;
|
|
|
|
}
|
|
|
|
|
|
|
|
void
|
|
|
|
BaseSession::Close()
|
|
|
|
{
|
|
|
|
if(state != eClose)
|
|
|
|
{
|
|
|
|
if(sock)
|
|
|
|
{
|
|
|
|
utp_shutdown(sock, SHUT_RDWR);
|
|
|
|
utp_close(sock);
|
|
|
|
llarp::LogDebug("utp_close ", remoteAddr);
|
|
|
|
utp_set_userdata(sock, nullptr);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
EnterState(eClose);
|
|
|
|
sock = nullptr;
|
|
|
|
}
|
|
|
|
|
|
|
|
void
|
|
|
|
BaseSession::Alive()
|
|
|
|
{
|
|
|
|
lastActive = llarp_time_now_ms();
|
|
|
|
}
|
|
|
|
|
|
|
|
} // namespace utp
|
|
|
|
|
|
|
|
} // namespace llarp
|