|
|
|
@ -1,5 +1,11 @@ |
|
|
|
|
|
|
|
#include <string.h> |
|
|
|
#include <boost/bind.hpp> |
|
|
|
#include <boost/bind.hpp> |
|
|
|
|
|
|
|
#include <cryptopp/dh.h> |
|
|
|
|
|
|
|
#include <cryptopp/secblock.h> |
|
|
|
|
|
|
|
#include "CryptoConst.h" |
|
|
|
#include "Log.h" |
|
|
|
#include "Log.h" |
|
|
|
|
|
|
|
#include "Timestamp.h" |
|
|
|
|
|
|
|
#include "RouterContext.h" |
|
|
|
#include "hmac.h" |
|
|
|
#include "hmac.h" |
|
|
|
#include "SSU.h" |
|
|
|
#include "SSU.h" |
|
|
|
|
|
|
|
|
|
|
|
@ -8,16 +14,244 @@ namespace i2p |
|
|
|
namespace ssu |
|
|
|
namespace ssu |
|
|
|
{ |
|
|
|
{ |
|
|
|
|
|
|
|
|
|
|
|
SSUSession::SSUSession (): m_State (eSessionStateUnknown) |
|
|
|
SSUSession::SSUSession (SSUServer * server, const boost::asio::ip::udp::endpoint& remoteEndpoint, |
|
|
|
|
|
|
|
i2p::data::RouterInfo * router): m_Server (server), m_RemoteEndpoint (remoteEndpoint), |
|
|
|
|
|
|
|
m_RemoteRouter (router), m_State (eSessionStateUnknown) |
|
|
|
{ |
|
|
|
{ |
|
|
|
} |
|
|
|
} |
|
|
|
|
|
|
|
|
|
|
|
void SSUSession::ProcessNextMessage (uint8_t * buf, std::size_t len) |
|
|
|
void SSUSession::CreateAESKey (uint8_t * pubKey, uint8_t * aesKey) // TODO: move it to base class for NTCP and SSU
|
|
|
|
{ |
|
|
|
{ |
|
|
|
|
|
|
|
CryptoPP::DH dh (i2p::crypto::elgp, i2p::crypto::elgg); |
|
|
|
|
|
|
|
CryptoPP::SecByteBlock secretKey(dh.AgreedValueLength()); |
|
|
|
|
|
|
|
if (!dh.Agree (secretKey, i2p::context.GetPrivateKey (), pubKey)) |
|
|
|
|
|
|
|
{ |
|
|
|
|
|
|
|
LogPrint ("Couldn't create shared key"); |
|
|
|
|
|
|
|
return; |
|
|
|
|
|
|
|
}; |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
if (secretKey[0] & 0x80) |
|
|
|
|
|
|
|
{ |
|
|
|
|
|
|
|
aesKey[0] = 0; |
|
|
|
|
|
|
|
memcpy (aesKey + 1, secretKey, 31); |
|
|
|
|
|
|
|
} |
|
|
|
|
|
|
|
else |
|
|
|
|
|
|
|
memcpy (aesKey, secretKey, 32); |
|
|
|
|
|
|
|
} |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
void SSUSession::ProcessNextMessage (uint8_t * buf, size_t len, const boost::asio::ip::udp::endpoint& senderEndpoint) |
|
|
|
|
|
|
|
{ |
|
|
|
|
|
|
|
switch (m_State) |
|
|
|
|
|
|
|
{ |
|
|
|
|
|
|
|
case eSessionStateUnknown: |
|
|
|
|
|
|
|
// session request
|
|
|
|
|
|
|
|
ProcessSessionRequest (buf, len, senderEndpoint); |
|
|
|
|
|
|
|
break; |
|
|
|
|
|
|
|
case eSessionStateRequestSent: |
|
|
|
|
|
|
|
// session created
|
|
|
|
|
|
|
|
ProcessSessionCreated (buf, len); |
|
|
|
|
|
|
|
break; |
|
|
|
|
|
|
|
default: |
|
|
|
|
|
|
|
LogPrint ("SSU state not implemented yet"); |
|
|
|
|
|
|
|
} |
|
|
|
|
|
|
|
} |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
void SSUSession::ProcessSessionRequest (uint8_t * buf, size_t len, const boost::asio::ip::udp::endpoint& senderEndpoint) |
|
|
|
|
|
|
|
{ |
|
|
|
|
|
|
|
LogPrint ("Process session request"); |
|
|
|
|
|
|
|
// use our intro key
|
|
|
|
|
|
|
|
if (ProcessIntroKeyEncryptedMessage (PAYLOAD_TYPE_SESSION_REQUEST, |
|
|
|
|
|
|
|
i2p::context.GetRouterInfo (), buf, len)) |
|
|
|
|
|
|
|
{ |
|
|
|
|
|
|
|
m_State = eSessionStateRequestReceived; |
|
|
|
|
|
|
|
LogPrint ("Session request received"); |
|
|
|
|
|
|
|
m_RemoteEndpoint = senderEndpoint; |
|
|
|
|
|
|
|
SendSessionCreated (buf + sizeof (SSUHeader)); |
|
|
|
|
|
|
|
} |
|
|
|
|
|
|
|
} |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
void SSUSession::ProcessSessionCreated (uint8_t * buf, size_t len) |
|
|
|
|
|
|
|
{ |
|
|
|
|
|
|
|
LogPrint ("Process session created"); |
|
|
|
|
|
|
|
if (!m_RemoteRouter) |
|
|
|
|
|
|
|
{ |
|
|
|
|
|
|
|
LogPrint ("Unsolicited session created message"); |
|
|
|
|
|
|
|
return; |
|
|
|
|
|
|
|
} |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
// use remote intro key
|
|
|
|
|
|
|
|
if (ProcessIntroKeyEncryptedMessage (PAYLOAD_TYPE_SESSION_CREATED, *m_RemoteRouter, buf, len)) |
|
|
|
|
|
|
|
{ |
|
|
|
|
|
|
|
m_State = eSessionStateCreatedReceived; |
|
|
|
|
|
|
|
LogPrint ("Session created received"); |
|
|
|
|
|
|
|
boost::asio::ip::address_v4 ourAddress (be32toh (*(uint32_t* )(buf + sizeof (SSUHeader) + 257))); |
|
|
|
|
|
|
|
uint16_t ourPort = be16toh (*(uint16_t *)(buf + sizeof (SSUHeader) + 261)); |
|
|
|
|
|
|
|
LogPrint ("Our external address is ", ourAddress.to_string (), ":", ourPort); |
|
|
|
|
|
|
|
} |
|
|
|
|
|
|
|
} |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
void SSUSession::SendSessionRequest () |
|
|
|
|
|
|
|
{ |
|
|
|
|
|
|
|
auto address = m_RemoteRouter ? m_RemoteRouter->GetSSUAddress () : nullptr; |
|
|
|
|
|
|
|
if (!address) |
|
|
|
|
|
|
|
{ |
|
|
|
|
|
|
|
LogPrint ("Missing remote SSU address"); |
|
|
|
|
|
|
|
return; |
|
|
|
|
|
|
|
} |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
uint8_t buf[304 + 18]; // 304 bytes for ipv4 (320 for ipv6)
|
|
|
|
|
|
|
|
uint8_t * payload = buf + sizeof (SSUHeader); |
|
|
|
|
|
|
|
memcpy (payload, i2p::context.GetRouterIdentity ().publicKey, 256); |
|
|
|
|
|
|
|
payload[256] = 4; // we assume ipv4
|
|
|
|
|
|
|
|
*(uint32_t *)(payload + 257) = htobe32 (address->host.to_v4 ().to_ulong ()); |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
uint8_t iv[16]; |
|
|
|
|
|
|
|
CryptoPP::RandomNumberGenerator& rnd = i2p::context.GetRandomNumberGenerator (); |
|
|
|
|
|
|
|
rnd.GenerateBlock (iv, 16); // random iv
|
|
|
|
|
|
|
|
FillHeaderAndEncrypt (PAYLOAD_TYPE_SESSION_REQUEST, buf, 304, address->key, iv, address->key); |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
m_State = eSessionStateRequestSent; |
|
|
|
|
|
|
|
m_Server->Send (buf, 304, m_RemoteEndpoint); |
|
|
|
|
|
|
|
} |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
void SSUSession::SendSessionCreated (const uint8_t * x) |
|
|
|
|
|
|
|
{ |
|
|
|
|
|
|
|
auto address = m_RemoteRouter ? m_RemoteRouter->GetSSUAddress () : nullptr; |
|
|
|
|
|
|
|
if (!address) |
|
|
|
|
|
|
|
{ |
|
|
|
|
|
|
|
LogPrint ("Missing remote SSU address"); |
|
|
|
|
|
|
|
return; |
|
|
|
|
|
|
|
} |
|
|
|
|
|
|
|
uint8_t signedData[532]; // x,y, remote IP, remote port, our IP, our port, relayTag, signed on time
|
|
|
|
|
|
|
|
memcpy (signedData, x, 256); // x
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
uint8_t buf[368 + 18]; |
|
|
|
|
|
|
|
uint8_t * payload = buf + sizeof (SSUHeader); |
|
|
|
|
|
|
|
memcpy (payload, i2p::context.GetRouterIdentity ().publicKey, 256); |
|
|
|
|
|
|
|
memcpy (signedData + 256, payload, 256); // y
|
|
|
|
|
|
|
|
payload += 256; |
|
|
|
|
|
|
|
*payload = 4; // we assume ipv4
|
|
|
|
|
|
|
|
payload++; |
|
|
|
|
|
|
|
*(uint32_t *)(payload) = htobe32 (m_RemoteEndpoint.address ().to_v4 ().to_ulong ()); |
|
|
|
|
|
|
|
payload += 4; |
|
|
|
|
|
|
|
*(uint16_t *)(payload) = htobe16 (m_RemoteEndpoint.port ()); |
|
|
|
|
|
|
|
payload += 2; |
|
|
|
|
|
|
|
memcpy (signedData + 512, payload - 6, 6); // remote endpoint IP and port
|
|
|
|
|
|
|
|
*(uint32_t *)(signedData + 518) = m_Server->GetEndpoint ().address ().to_v4 ().to_ulong (); // our IP
|
|
|
|
|
|
|
|
*(uint16_t *)(signedData + 522) = htobe16 (m_Server->GetEndpoint ().port ()); // our port
|
|
|
|
|
|
|
|
*(uint32_t *)(payload) = 0; // relay tag, always 0 for now
|
|
|
|
|
|
|
|
payload += 4; |
|
|
|
|
|
|
|
*(uint32_t *)(payload) = htobe32 (i2p::util::GetSecondsSinceEpoch ()); // signed on time
|
|
|
|
|
|
|
|
payload += 4; |
|
|
|
|
|
|
|
memcpy (signedData + 524, payload - 8, 8); // relayTag and signed on time
|
|
|
|
|
|
|
|
i2p::context.Sign (signedData, 532, payload); // DSA signature
|
|
|
|
|
|
|
|
// TODO: fill padding with random data
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
uint8_t iv[16]; |
|
|
|
|
|
|
|
CryptoPP::RandomNumberGenerator& rnd = i2p::context.GetRandomNumberGenerator (); |
|
|
|
|
|
|
|
rnd.GenerateBlock (iv, 16); // random iv
|
|
|
|
|
|
|
|
// encrypt signature and 8 bytes padding with newly created session key
|
|
|
|
|
|
|
|
m_Encryption.SetKeyWithIV (m_SessionKey, 32, iv); |
|
|
|
|
|
|
|
m_Encryption.ProcessData (payload, payload, 48); |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
// encrypt message with intro key
|
|
|
|
|
|
|
|
FillHeaderAndEncrypt (PAYLOAD_TYPE_SESSION_CREATED, buf, 368, address->key, iv, address->key); |
|
|
|
|
|
|
|
m_State = eSessionStateRequestSent; |
|
|
|
|
|
|
|
m_Server->Send (buf, 368, m_RemoteEndpoint); |
|
|
|
|
|
|
|
} |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
bool SSUSession::ProcessIntroKeyEncryptedMessage (uint8_t expectedPayloadType, i2p::data::RouterInfo& r, uint8_t * buf, size_t len) |
|
|
|
|
|
|
|
{ |
|
|
|
|
|
|
|
auto address = r.GetSSUAddress (); |
|
|
|
|
|
|
|
if (address) |
|
|
|
|
|
|
|
{ |
|
|
|
|
|
|
|
// use intro key for verification and decryption
|
|
|
|
|
|
|
|
if (Validate (buf, len, address->key)) |
|
|
|
|
|
|
|
{ |
|
|
|
|
|
|
|
Decrypt (buf, len, address->key); |
|
|
|
|
|
|
|
SSUHeader * header = (SSUHeader *)buf; |
|
|
|
|
|
|
|
if ((header->flag >> 4) == expectedPayloadType) |
|
|
|
|
|
|
|
{ |
|
|
|
|
|
|
|
CreateAESKey (buf + sizeof (SSUHeader), m_SessionKey); |
|
|
|
|
|
|
|
return true; |
|
|
|
|
|
|
|
} |
|
|
|
|
|
|
|
else |
|
|
|
|
|
|
|
LogPrint ("Unexpected payload type ", (int)(header->flag >> 4)); |
|
|
|
|
|
|
|
} |
|
|
|
|
|
|
|
else |
|
|
|
|
|
|
|
LogPrint ("MAC verifcation failed"); |
|
|
|
|
|
|
|
} |
|
|
|
|
|
|
|
else |
|
|
|
|
|
|
|
LogPrint ("SSU is not supported by ", r.GetIdentHashAbbreviation ()); |
|
|
|
|
|
|
|
return false; |
|
|
|
|
|
|
|
} |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
void SSUSession::FillHeaderAndEncrypt (uint8_t payloadType, uint8_t * buf, size_t len, uint8_t * aesKey, uint8_t * iv, uint8_t * macKey) |
|
|
|
|
|
|
|
{ |
|
|
|
|
|
|
|
if (len < sizeof (SSUHeader)) |
|
|
|
|
|
|
|
{ |
|
|
|
|
|
|
|
LogPrint ("Unexpected SSU packet length ", len); |
|
|
|
|
|
|
|
return; |
|
|
|
|
|
|
|
} |
|
|
|
|
|
|
|
SSUHeader * header = (SSUHeader *)buf; |
|
|
|
|
|
|
|
memcpy (header->iv, iv, 16); |
|
|
|
|
|
|
|
header->flag = payloadType << 4; // MSB is 0
|
|
|
|
|
|
|
|
header->time = htobe32 (i2p::util::GetSecondsSinceEpoch ()); |
|
|
|
|
|
|
|
uint8_t * encrypted = &header->flag; |
|
|
|
|
|
|
|
uint16_t encryptedLen = len - (encrypted - buf); |
|
|
|
|
|
|
|
m_Encryption.SetKeyWithIV (aesKey, 32, iv); |
|
|
|
|
|
|
|
m_Encryption.ProcessData (encrypted, encrypted, encryptedLen); |
|
|
|
|
|
|
|
// assume actual buffer size is 18 (16 + 2) bytes more
|
|
|
|
|
|
|
|
memcpy (buf + len, iv, 16); |
|
|
|
|
|
|
|
*(uint16_t *)(buf + len + 16) = htobe16 (encryptedLen); |
|
|
|
|
|
|
|
i2p::crypto::HMACMD5Digest (encrypted, encryptedLen + 18, macKey, header->mac); |
|
|
|
|
|
|
|
} |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
void SSUSession::Decrypt (uint8_t * buf, size_t len, uint8_t * aesKey) |
|
|
|
|
|
|
|
{ |
|
|
|
|
|
|
|
if (len < sizeof (SSUHeader)) |
|
|
|
|
|
|
|
{ |
|
|
|
|
|
|
|
LogPrint ("Unexpected SSU packet length ", len); |
|
|
|
|
|
|
|
return; |
|
|
|
|
|
|
|
} |
|
|
|
|
|
|
|
SSUHeader * header = (SSUHeader *)buf; |
|
|
|
|
|
|
|
uint8_t * encrypted = &header->flag; |
|
|
|
|
|
|
|
uint16_t encryptedLen = len - (encrypted - buf); |
|
|
|
|
|
|
|
m_Decryption.SetKeyWithIV (aesKey, 32, header->iv); |
|
|
|
|
|
|
|
encryptedLen = (encryptedLen/16)*16; // make sure 16 bytes boundary
|
|
|
|
|
|
|
|
m_Decryption.ProcessData (encrypted, encrypted, encryptedLen); |
|
|
|
|
|
|
|
} |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
bool SSUSession::Validate (uint8_t * buf, size_t len, uint8_t * macKey) |
|
|
|
|
|
|
|
{ |
|
|
|
|
|
|
|
if (len < sizeof (SSUHeader)) |
|
|
|
|
|
|
|
{ |
|
|
|
|
|
|
|
LogPrint ("Unexpected SSU packet length ", len); |
|
|
|
|
|
|
|
return false; |
|
|
|
|
|
|
|
} |
|
|
|
|
|
|
|
SSUHeader * header = (SSUHeader *)buf; |
|
|
|
|
|
|
|
uint8_t * encrypted = &header->flag; |
|
|
|
|
|
|
|
uint16_t encryptedLen = len - (encrypted - buf); |
|
|
|
|
|
|
|
// assume actual buffer size is 18 (16 + 2) bytes more
|
|
|
|
|
|
|
|
memcpy (buf + len, header->iv, 16); |
|
|
|
|
|
|
|
*(uint16_t *)(buf + len + 16) = htobe16 (encryptedLen); |
|
|
|
|
|
|
|
uint8_t digest[16]; |
|
|
|
|
|
|
|
i2p::crypto::HMACMD5Digest (encrypted, encryptedLen + 18, macKey, digest); |
|
|
|
|
|
|
|
return !memcmp (header->mac, digest, 16); |
|
|
|
|
|
|
|
} |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
void SSUSession::Connect () |
|
|
|
|
|
|
|
{ |
|
|
|
|
|
|
|
SendSessionRequest (); |
|
|
|
|
|
|
|
} |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
void SSUSession::SendI2NPMessage (I2NPMessage * msg) |
|
|
|
|
|
|
|
{ |
|
|
|
|
|
|
|
// TODO:
|
|
|
|
} |
|
|
|
} |
|
|
|
|
|
|
|
|
|
|
|
SSUServer::SSUServer (boost::asio::io_service& service, int port): |
|
|
|
SSUServer::SSUServer (boost::asio::io_service& service, int port): |
|
|
|
m_Socket (service, boost::asio::ip::udp::v4 (), port) |
|
|
|
m_Endpoint (boost::asio::ip::udp::v4 (), port), m_Socket (service, m_Endpoint) |
|
|
|
{ |
|
|
|
{ |
|
|
|
} |
|
|
|
} |
|
|
|
|
|
|
|
|
|
|
|
@ -37,6 +271,11 @@ namespace ssu |
|
|
|
m_Socket.close (); |
|
|
|
m_Socket.close (); |
|
|
|
} |
|
|
|
} |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
void SSUServer::Send (uint8_t * buf, size_t len, const boost::asio::ip::udp::endpoint& to) |
|
|
|
|
|
|
|
{ |
|
|
|
|
|
|
|
m_Socket.send_to (boost::asio::buffer (buf, len), to); |
|
|
|
|
|
|
|
} |
|
|
|
|
|
|
|
|
|
|
|
void SSUServer::Receive () |
|
|
|
void SSUServer::Receive () |
|
|
|
{ |
|
|
|
{ |
|
|
|
m_Socket.async_receive_from (boost::asio::buffer (m_ReceiveBuffer, SSU_MTU), m_SenderEndpoint, |
|
|
|
m_Socket.async_receive_from (boost::asio::buffer (m_ReceiveBuffer, SSU_MTU), m_SenderEndpoint, |
|
|
|
@ -52,18 +291,46 @@ namespace ssu |
|
|
|
auto it = m_Sessions.find (m_SenderEndpoint); |
|
|
|
auto it = m_Sessions.find (m_SenderEndpoint); |
|
|
|
if (it != m_Sessions.end ()) |
|
|
|
if (it != m_Sessions.end ()) |
|
|
|
session = it->second; |
|
|
|
session = it->second; |
|
|
|
if (session) |
|
|
|
if (!session) |
|
|
|
{ |
|
|
|
{ |
|
|
|
session = new SSUSession (); |
|
|
|
session = new SSUSession (this, m_SenderEndpoint); |
|
|
|
m_Sessions[m_SenderEndpoint] = session; |
|
|
|
m_Sessions[m_SenderEndpoint] = session; |
|
|
|
LogPrint ("New SSU session from ", m_SenderEndpoint.address ().to_string (), ":", m_SenderEndpoint.port (), " created"); |
|
|
|
LogPrint ("New SSU session from ", m_SenderEndpoint.address ().to_string (), ":", m_SenderEndpoint.port (), " created"); |
|
|
|
} |
|
|
|
} |
|
|
|
session->ProcessNextMessage (m_ReceiveBuffer, bytes_transferred); |
|
|
|
session->ProcessNextMessage (m_ReceiveBuffer, bytes_transferred, m_SenderEndpoint); |
|
|
|
Receive (); |
|
|
|
Receive (); |
|
|
|
} |
|
|
|
} |
|
|
|
else |
|
|
|
else |
|
|
|
LogPrint ("SSU receive error: ", ecode.message ()); |
|
|
|
LogPrint ("SSU receive error: ", ecode.message ()); |
|
|
|
} |
|
|
|
} |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
SSUSession * SSUServer::GetSession (i2p::data::RouterInfo * router) |
|
|
|
|
|
|
|
{ |
|
|
|
|
|
|
|
SSUSession * session = nullptr; |
|
|
|
|
|
|
|
if (router) |
|
|
|
|
|
|
|
{ |
|
|
|
|
|
|
|
auto address = router->GetSSUAddress (); |
|
|
|
|
|
|
|
if (address) |
|
|
|
|
|
|
|
{ |
|
|
|
|
|
|
|
boost::asio::ip::udp::endpoint remoteEndpoint (address->host, address->port); |
|
|
|
|
|
|
|
auto it = m_Sessions.find (remoteEndpoint); |
|
|
|
|
|
|
|
if (it != m_Sessions.end ()) |
|
|
|
|
|
|
|
session = it->second; |
|
|
|
|
|
|
|
else |
|
|
|
|
|
|
|
{ |
|
|
|
|
|
|
|
// otherwise create new session
|
|
|
|
|
|
|
|
session = new SSUSession (this, remoteEndpoint, router); |
|
|
|
|
|
|
|
m_Sessions[remoteEndpoint] = session; |
|
|
|
|
|
|
|
LogPrint ("New SSU session to [", router->GetIdentHashAbbreviation (), "] ", |
|
|
|
|
|
|
|
remoteEndpoint.address ().to_string (), ":", remoteEndpoint.port (), " created"); |
|
|
|
|
|
|
|
session->Connect (); |
|
|
|
|
|
|
|
} |
|
|
|
|
|
|
|
} |
|
|
|
|
|
|
|
else |
|
|
|
|
|
|
|
LogPrint ("Router ", router->GetIdentHashAbbreviation (), " doesn't have SSU address"); |
|
|
|
|
|
|
|
} |
|
|
|
|
|
|
|
return session; |
|
|
|
|
|
|
|
} |
|
|
|
} |
|
|
|
} |
|
|
|
} |
|
|
|
} |
|
|
|
|
|
|
|
|
|
|
|
|
chertov
11 years ago