@ -13,12 +13,12 @@ namespace i2p
namespace transport
{
SSUSession : : SSUSession ( SSUServer & server , boost : : asio : : ip : : udp : : endpoint & remoteEndpoint ,
std : : shared_ptr < const i2p : : data : : RouterInfo > router , bool peerTest ) :
TransportSession ( router , SSU_TERMINATION_TIMEOUT ) ,
m_Server ( server ) , m_RemoteEndpoint ( remoteEndpoint ) , m_ConnectTimer ( GetService ( ) ) ,
m_IsPeerTest ( peerTest ) , m_State ( eSessionStateUnknown ) , m_IsSessionKey ( false ) ,
std : : shared_ptr < const i2p : : data : : RouterInfo > router , bool peerTest ) :
TransportSession ( router , SSU_TERMINATION_TIMEOUT ) ,
m_Server ( server ) , m_RemoteEndpoint ( remoteEndpoint ) , m_ConnectTimer ( GetService ( ) ) ,
m_IsPeerTest ( peerTest ) , m_State ( eSessionStateUnknown ) , m_IsSessionKey ( false ) ,
m_RelayTag ( 0 ) , m_SentRelayTag ( 0 ) , m_Data ( * this ) , m_IsDataReceived ( false )
{
{
if ( router )
{
// we are client
@ -36,14 +36,14 @@ namespace transport
}
SSUSession : : ~ SSUSession ( )
{
}
{
}
boost : : asio : : io_service & SSUSession : : GetService ( )
{
return IsV6 ( ) ? m_Server . GetServiceV6 ( ) : m_Server . GetService ( ) ;
boost : : asio : : io_service & SSUSession : : GetService ( )
{
return IsV6 ( ) ? m_Server . GetServiceV6 ( ) : m_Server . GetService ( ) ;
}
void SSUSession : : CreateAESandMacKey ( const uint8_t * pubKey )
{
uint8_t sharedKey [ 256 ] ;
@ -55,14 +55,14 @@ namespace transport
sessionKey [ 0 ] = 0 ;
memcpy ( sessionKey + 1 , sharedKey , 31 ) ;
memcpy ( macKey , sharedKey + 31 , 32 ) ;
}
}
else if ( sharedKey [ 0 ] )
{
memcpy ( sessionKey , sharedKey , 32 ) ;
memcpy ( macKey , sharedKey + 32 , 32 ) ;
}
}
else
{
{
// find first non-zero byte
uint8_t * nonZero = sharedKey + 1 ;
while ( ! * nonZero )
@ -72,16 +72,16 @@ namespace transport
{
LogPrint ( eLogWarning , " SSU: first 32 bytes of shared key is all zeros. Ignored " ) ;
return ;
}
}
}
memcpy ( sessionKey , nonZero , 32 ) ;
SHA256 ( nonZero , 64 - ( nonZero - sharedKey ) , macKey ) ;
}
m_IsSessionKey = true ;
m_SessionKeyEncryption . SetKey ( m_SessionKey ) ;
m_SessionKeyDecryption . SetKey ( m_SessionKey ) ;
}
}
void SSUSession : : ProcessNextMessage ( uint8_t * buf , size_t len , const boost : : asio : : ip : : udp : : endpoint & senderEndpoint )
{
@ -96,40 +96,40 @@ namespace transport
}
else
{
if ( ! len ) return ; // ignore zero-length packets
if ( ! len ) return ; // ignore zero-length packets
if ( m_State = = eSessionStateEstablished )
m_LastActivityTimestamp = i2p : : util : : GetSecondsSinceEpoch ( ) ;
m_LastActivityTimestamp = i2p : : util : : GetSecondsSinceEpoch ( ) ;
if ( m_IsSessionKey & & Validate ( buf , len , m_MacKey ) ) // try session key first
DecryptSessionKey ( buf , len ) ;
else
DecryptSessionKey ( buf , len ) ;
else
{
if ( m_State = = eSessionStateEstablished ) Reset ( ) ; // new session key required
if ( m_State = = eSessionStateEstablished ) Reset ( ) ; // new session key required
// try intro key depending on side
if ( Validate ( buf , len , m_IntroKey ) )
Decrypt ( buf , len , m_IntroKey ) ;
else
{
{
// try own intro key
auto address = i2p : : context . GetRouterInfo ( ) . GetSSUAddress ( false ) ;
if ( ! address )
{
LogPrint ( eLogInfo , " SSU is not supported " ) ;
return ;
}
}
if ( Validate ( buf , len , address - > ssu - > key ) )
Decrypt ( buf , len , address - > ssu - > key ) ;
else
{
LogPrint ( eLogWarning , " SSU: MAC verification failed " , len , " bytes from " , senderEndpoint ) ;
m_Server . DeleteSession ( shared_from_this ( ) ) ;
m_Server . DeleteSession ( shared_from_this ( ) ) ;
return ;
}
}
}
}
}
}
// successfully decrypted
ProcessMessage ( buf , len , senderEndpoint ) ;
}
}
}
size_t SSUSession : : GetSSUHeaderSize ( const uint8_t * buf ) const
@ -158,14 +158,14 @@ namespace transport
ProcessData ( buf + headerSize , len - headerSize ) ;
break ;
case PAYLOAD_TYPE_SESSION_REQUEST :
ProcessSessionRequest ( buf , len , senderEndpoint ) ; // buf with header
ProcessSessionRequest ( buf , len , senderEndpoint ) ; // buf with header
break ;
case PAYLOAD_TYPE_SESSION_CREATED :
ProcessSessionCreated ( buf , len ) ; // buf with header
break ;
case PAYLOAD_TYPE_SESSION_CONFIRMED :
ProcessSessionConfirmed ( buf , len ) ; // buf with header
break ;
break ;
case PAYLOAD_TYPE_PEER_TEST :
LogPrint ( eLogDebug , " SSU: peer test received " ) ;
ProcessPeerTest ( buf + headerSize , len - headerSize , senderEndpoint ) ;
@ -173,9 +173,9 @@ namespace transport
case PAYLOAD_TYPE_SESSION_DESTROYED :
{
LogPrint ( eLogDebug , " SSU: session destroy received " ) ;
m_Server . DeleteSession ( shared_from_this ( ) ) ;
m_Server . DeleteSession ( shared_from_this ( ) ) ;
break ;
}
}
case PAYLOAD_TYPE_RELAY_RESPONSE :
ProcessRelayResponse ( buf + headerSize , len - headerSize ) ;
if ( m_State ! = eSessionStateEstablished )
@ -197,7 +197,7 @@ namespace transport
void SSUSession : : ProcessSessionRequest ( const uint8_t * buf , size_t len , const boost : : asio : : ip : : udp : : endpoint & senderEndpoint )
{
LogPrint ( eLogDebug , " SSU message: session request " ) ;
bool sendRelayTag = true ;
bool sendRelayTag = true ;
auto headerSize = sizeof ( SSUHeader ) ;
if ( ( ( SSUHeader * ) buf ) - > IsExtendedOptions ( ) )
{
@ -206,14 +206,14 @@ namespace transport
if ( extendedOptionsLen > = 3 ) // options are presented
{
uint16_t flags = bufbe16toh ( buf + headerSize ) ;
sendRelayTag = flags & EXTENDED_OPTIONS_FLAG_REQUEST_RELAY_TAG ;
sendRelayTag = flags & EXTENDED_OPTIONS_FLAG_REQUEST_RELAY_TAG ;
}
headerSize + = extendedOptionsLen ;
}
}
if ( headerSize > = len )
{
LogPrint ( eLogError , " Session reaquest header size " , headerSize , " exceeds packet length " , len ) ;
return ;
return ;
}
m_RemoteEndpoint = senderEndpoint ;
if ( ! m_DHKeysPair )
@ -232,14 +232,14 @@ namespace transport
LogPrint ( eLogDebug , " SSU message: session created " ) ;
m_ConnectTimer . cancel ( ) ; // connect timer
SignedData s ; // x,y, our IP, our port, remote IP, remote port, relayTag, signed on time
auto headerSize = GetSSUHeaderSize ( buf ) ;
SignedData s ; // x,y, our IP, our port, remote IP, remote port, relayTag, signed on time
auto headerSize = GetSSUHeaderSize ( buf ) ;
if ( headerSize > = len )
{
LogPrint ( eLogError , " Session created header size " , headerSize , " exceeds packet length " , len ) ;
return ;
}
uint8_t * payload = buf + headerSize ;
return ;
}
uint8_t * payload = buf + headerSize ;
uint8_t * y = payload ;
CreateAESandMacKey ( y ) ;
s . Insert ( m_DHKeysPair - > GetPublicKey ( ) , 256 ) ; // x
@ -250,18 +250,18 @@ namespace transport
uint8_t * ourAddress = payload ;
boost : : asio : : ip : : address ourIP ;
if ( addressSize = = 4 ) // v4
{
{
boost : : asio : : ip : : address_v4 : : bytes_type bytes ;
memcpy ( bytes . data ( ) , ourAddress , 4 ) ;
ourIP = boost : : asio : : ip : : address_v4 ( bytes ) ;
}
}
else // v6
{
boost : : asio : : ip : : address_v6 : : bytes_type bytes ;
memcpy ( bytes . data ( ) , ourAddress , 16 ) ;
ourIP = boost : : asio : : ip : : address_v6 ( bytes ) ;
}
s . Insert ( ourAddress , addressSize ) ; // our IP
}
s . Insert ( ourAddress , addressSize ) ; // our IP
payload + = addressSize ; // address
uint16_t ourPort = bufbe16toh ( payload ) ;
s . Insert ( payload , 2 ) ; // our port
@ -271,19 +271,19 @@ namespace transport
else
s . Insert ( m_RemoteEndpoint . address ( ) . to_v6 ( ) . to_bytes ( ) . data ( ) , 16 ) ; // remote IP v6
s . Insert < uint16_t > ( htobe16 ( m_RemoteEndpoint . port ( ) ) ) ; // remote port
s . Insert ( payload , 8 ) ; // relayTag and signed on time
s . Insert ( payload , 8 ) ; // relayTag and signed on time
m_RelayTag = bufbe32toh ( payload ) ;
payload + = 4 ; // relayTag
if ( i2p : : context . GetStatus ( ) = = eRouterStatusTesting )
{
{
auto ts = i2p : : util : : GetSecondsSinceEpoch ( ) ;
uint32_t signedOnTime = bufbe32toh ( payload ) ;
if ( signedOnTime < ts - SSU_CLOCK_SKEW | | signedOnTime > ts + SSU_CLOCK_SKEW )
{
LogPrint ( eLogError , " SSU: clock skew detected " , ( int ) ts - signedOnTime , " . Check your clock " ) ;
LogPrint ( eLogError , " SSU: clock skew detected " , ( int ) ts - signedOnTime , " . Check your clock " ) ;
i2p : : context . SetError ( eRouterErrorClockSkew ) ;
}
}
}
payload + = 4 ; // signed on time
// decrypt signature
size_t signatureLen = m_RemoteIdentity - > GetSignatureLen ( ) ;
@ -304,34 +304,34 @@ namespace transport
LogPrint ( eLogError , " SSU: message 'created' signature verification failed " ) ;
Failed ( ) ;
}
}
}
void SSUSession : : ProcessSessionConfirmed ( const uint8_t * buf , size_t len )
{
LogPrint ( eLogDebug , " SSU: Session confirmed received " ) ;
auto headerSize = GetSSUHeaderSize ( buf ) ;
LogPrint ( eLogDebug , " SSU: Session confirmed received " ) ;
auto headerSize = GetSSUHeaderSize ( buf ) ;
if ( headerSize > = len )
{
LogPrint ( eLogError , " SSU: Session confirmed header size " , len , " exceeds packet length " , len ) ;
return ;
}
return ;
}
const uint8_t * payload = buf + headerSize ;
payload + + ; // identity fragment info
uint16_t identitySize = bufbe16toh ( payload ) ;
uint16_t identitySize = bufbe16toh ( payload ) ;
payload + = 2 ; // size of identity fragment
auto identity = std : : make_shared < i2p : : data : : IdentityEx > ( payload , identitySize ) ;
auto existing = i2p : : data : : netdb . FindRouter ( identity - > GetIdentHash ( ) ) ; // check if exists already
SetRemoteIdentity ( existing ? existing - > GetRouterIdentity ( ) : identity ) ;
m_Data . UpdatePacketSize ( m_RemoteIdentity - > GetIdentHash ( ) ) ;
payload + = identitySize ; // identity
payload + = identitySize ; // identity
auto ts = i2p : : util : : GetSecondsSinceEpoch ( ) ;
uint32_t signedOnTime = bufbe32toh ( payload ) ;
uint32_t signedOnTime = bufbe32toh ( payload ) ;
if ( signedOnTime < ts - SSU_CLOCK_SKEW | | signedOnTime > ts + SSU_CLOCK_SKEW )
{
LogPrint ( eLogError , " SSU message 'confirmed' time difference " , ( int ) ts - signedOnTime , " exceeds clock skew " ) ;
LogPrint ( eLogError , " SSU message 'confirmed' time difference " , ( int ) ts - signedOnTime , " exceeds clock skew " ) ;
Failed ( ) ;
return ;
}
}
if ( m_SignedData )
m_SignedData - > Insert ( payload , 4 ) ; // insert Alice's signed on time
payload + = 4 ; // signed-on time
@ -345,7 +345,7 @@ namespace transport
m_Data . Send ( CreateDeliveryStatusMsg ( 0 ) ) ;
Established ( ) ;
}
else
else
{
LogPrint ( eLogError , " SSU message 'confirmed' signature verification failed " ) ;
Failed ( ) ;
@ -353,33 +353,33 @@ namespace transport
}
void SSUSession : : SendSessionRequest ( )
{
{
uint8_t buf [ 320 + 18 ] = { 0 } ; // 304 bytes for ipv4, 320 for ipv6
uint8_t * payload = buf + sizeof ( SSUHeader ) ;
uint8_t flag = 0 ;
// fill extended options, 3 bytes extended options don't change message size
if ( i2p : : context . GetStatus ( ) = = eRouterStatusOK ) // we don't need relays
{
{
// tell out peer to now assign relay tag
flag = SSU_HEADER_EXTENDED_OPTIONS_INCLUDED ;
* payload = 2 ; payload + + ; // 1 byte length
uint16_t flags = 0 ; // clear EXTENDED_OPTIONS_FLAG_REQUEST_RELAY_TAG
htobe16buf ( payload , flags ) ;
htobe16buf ( payload , flags ) ;
payload + = 2 ;
}
}
// fill payload
memcpy ( payload , m_DHKeysPair - > GetPublicKey ( ) , 256 ) ; // x
bool isV4 = m_RemoteEndpoint . address ( ) . is_v4 ( ) ;
if ( isV4 )
{
payload [ 256 ] = 4 ;
memcpy ( payload + 257 , m_RemoteEndpoint . address ( ) . to_v4 ( ) . to_bytes ( ) . data ( ) , 4 ) ;
payload [ 256 ] = 4 ;
memcpy ( payload + 257 , m_RemoteEndpoint . address ( ) . to_v4 ( ) . to_bytes ( ) . data ( ) , 4 ) ;
}
else
{
payload [ 256 ] = 16 ;
memcpy ( payload + 257 , m_RemoteEndpoint . address ( ) . to_v6 ( ) . to_bytes ( ) . data ( ) , 16 ) ;
}
payload [ 256 ] = 16 ;
memcpy ( payload + 257 , m_RemoteEndpoint . address ( ) . to_v6 ( ) . to_bytes ( ) . data ( ) , 16 ) ;
}
// encrypt and send
uint8_t iv [ 16 ] ;
RAND_bytes ( iv , 16 ) ; // random iv
@ -395,7 +395,7 @@ namespace transport
LogPrint ( eLogInfo , " SSU is not supported " ) ;
return ;
}
uint8_t buf [ 96 + 18 ] = { 0 } ;
uint8_t * payload = buf + sizeof ( SSUHeader ) ;
htobe32buf ( payload , introducer . iTag ) ;
@ -405,17 +405,17 @@ namespace transport
htobuf16 ( payload , 0 ) ; // port = 0
payload + = 2 ;
* payload = 0 ; // challenge
payload + + ;
payload + + ;
memcpy ( payload , ( const uint8_t * ) address - > ssu - > key , 32 ) ;
payload + = 32 ;
htobe32buf ( payload , nonce ) ; // nonce
htobe32buf ( payload , nonce ) ; // nonce
uint8_t iv [ 16 ] ;
RAND_bytes ( iv , 16 ) ; // random iv
if ( m_State = = eSessionStateEstablished )
FillHeaderAndEncrypt ( PAYLOAD_TYPE_RELAY_REQUEST , buf , 96 , m_SessionKey , iv , m_MacKey ) ;
else
FillHeaderAndEncrypt ( PAYLOAD_TYPE_RELAY_REQUEST , buf , 96 , introducer . iKey , iv , introducer . iKey ) ;
FillHeaderAndEncrypt ( PAYLOAD_TYPE_RELAY_REQUEST , buf , 96 , introducer . iKey , iv , introducer . iKey ) ;
m_Server . Send ( buf , 96 , m_RemoteEndpoint ) ;
}
@ -428,7 +428,7 @@ namespace transport
LogPrint ( eLogInfo , " SSU is not supported " ) ;
return ;
}
SignedData s ; // x,y, remote IP, remote port, our IP, our port, relayTag, signed on time
SignedData s ; // x,y, remote IP, remote port, our IP, our port, relayTag, signed on time
s . Insert ( x , 256 ) ; // x
uint8_t buf [ 384 + 18 ] = { 0 } ;
@ -441,7 +441,7 @@ namespace transport
// ipv4
* payload = 4 ;
payload + + ;
memcpy ( payload , m_RemoteEndpoint . address ( ) . to_v4 ( ) . to_bytes ( ) . data ( ) , 4 ) ;
memcpy ( payload , m_RemoteEndpoint . address ( ) . to_v4 ( ) . to_bytes ( ) . data ( ) , 4 ) ;
s . Insert ( payload , 4 ) ; // remote endpoint IP V4
payload + = 4 ;
}
@ -450,7 +450,7 @@ namespace transport
// ipv6
* payload = 16 ;
payload + + ;
memcpy ( payload , m_RemoteEndpoint . address ( ) . to_v6 ( ) . to_bytes ( ) . data ( ) , 16 ) ;
memcpy ( payload , m_RemoteEndpoint . address ( ) . to_v6 ( ) . to_bytes ( ) . data ( ) , 16 ) ;
s . Insert ( payload , 16 ) ; // remote endpoint IP V6
payload + = 16 ;
}
@ -467,20 +467,20 @@ namespace transport
RAND_bytes ( ( uint8_t * ) & m_SentRelayTag , 4 ) ;
if ( ! m_SentRelayTag ) m_SentRelayTag = 1 ;
}
htobe32buf ( payload , m_SentRelayTag ) ;
payload + = 4 ; // relay tag
htobe32buf ( payload , m_SentRelayTag ) ;
payload + = 4 ; // relay tag
htobe32buf ( payload , i2p : : util : : GetSecondsSinceEpoch ( ) ) ; // signed on time
payload + = 4 ;
s . Insert ( payload - 8 , 4 ) ; // relayTag
s . Insert ( payload - 8 , 4 ) ; // relayTag
// we have to store this signed data for session confirmed
// same data but signed on time, it will Alice's there
m_SignedData = std : : unique_ptr < SignedData > ( new SignedData ( s ) ) ;
s . Insert ( payload - 4 , 4 ) ; // BOB's signed on time
// same data but signed on time, it will Alice's there
m_SignedData = std : : unique_ptr < SignedData > ( new SignedData ( s ) ) ;
s . Insert ( payload - 4 , 4 ) ; // BOB's signed on time
s . Sign ( i2p : : context . GetPrivateKeys ( ) , payload ) ; // DSA signature
uint8_t iv [ 16 ] ;
RAND_bytes ( iv , 16 ) ; // random iv
// encrypt signature and padding with newly created session key
// encrypt signature and padding with newly created session key
size_t signatureLen = i2p : : context . GetIdentity ( ) - > GetSignatureLen ( ) ;
size_t paddingSize = signatureLen & 0x0F ; // %16
if ( paddingSize > 0 )
@ -493,9 +493,9 @@ namespace transport
m_SessionKeyEncryption . Encrypt ( payload , signatureLen , payload ) ;
payload + = signatureLen ;
size_t msgLen = payload - buf ;
// encrypt message with intro key
FillHeaderAndEncrypt ( PAYLOAD_TYPE_SESSION_CREATED , buf , msgLen , m_IntroKey , iv , m_IntroKey ) ;
FillHeaderAndEncrypt ( PAYLOAD_TYPE_SESSION_CREATED , buf , msgLen , m_IntroKey , iv , m_IntroKey ) ;
Send ( buf , msgLen ) ;
}
@ -518,21 +518,21 @@ namespace transport
if ( paddingSize > 0 ) paddingSize = 16 - paddingSize ;
RAND_bytes ( payload , paddingSize ) ; // fill padding with random
payload + = paddingSize ; // padding size
// signature
SignedData s ; // x,y, our IP, our port, remote IP, remote port, relayTag, our signed on time
// signature
SignedData s ; // x,y, our IP, our port, remote IP, remote port, relayTag, our signed on time
s . Insert ( m_DHKeysPair - > GetPublicKey ( ) , 256 ) ; // x
s . Insert ( y , 256 ) ; // y
s . Insert ( ourAddress , ourAddressLen ) ; // our address/port as seem by party
if ( m_RemoteEndpoint . address ( ) . is_v4 ( ) )
s . Insert ( m_RemoteEndpoint . address ( ) . to_v4 ( ) . to_bytes ( ) . data ( ) , 4 ) ; // remote IP V4
else
s . Insert ( m_RemoteEndpoint . address ( ) . to_v6 ( ) . to_bytes ( ) . data ( ) , 16 ) ; // remote IP V6
s . Insert ( m_RemoteEndpoint . address ( ) . to_v6 ( ) . to_bytes ( ) . data ( ) , 16 ) ; // remote IP V6
s . Insert < uint16_t > ( htobe16 ( m_RemoteEndpoint . port ( ) ) ) ; // remote port
s . Insert ( htobe32 ( m_RelayTag ) ) ; // relay tag
s . Insert ( htobe32 ( signedOnTime ) ) ; // signed on time
s . Sign ( i2p : : context . GetPrivateKeys ( ) , payload ) ; // DSA signature
s . Sign ( i2p : : context . GetPrivateKeys ( ) , payload ) ; // DSA signature
payload + = signatureLen ;
size_t msgLen = payload - buf ;
uint8_t iv [ 16 ] ;
RAND_bytes ( iv , 16 ) ; // random iv
@ -547,7 +547,7 @@ namespace transport
auto session = m_Server . FindRelaySession ( relayTag ) ;
if ( session )
{
buf + = 4 ; // relay tag
buf + = 4 ; // relay tag
uint8_t size = * buf ;
buf + + ; // size
buf + = size ; // address
@ -560,7 +560,7 @@ namespace transport
uint32_t nonce = bufbe32toh ( buf ) ;
SendRelayResponse ( nonce , from , introKey , session - > m_RemoteEndpoint ) ;
SendRelayIntro ( session , from ) ;
}
}
}
void SSUSession : : SendRelayResponse ( uint32_t nonce , const boost : : asio : : ip : : udp : : endpoint & from ,
@ -577,7 +577,7 @@ namespace transport
* payload = 4 ;
payload + + ; // size
htobe32buf ( payload , to . address ( ) . to_v4 ( ) . to_ulong ( ) ) ; // Charlie's IP
payload + = 4 ; // address
payload + = 4 ; // address
htobe16buf ( payload , to . port ( ) ) ; // Charlie's port
payload + = 2 ; // port
// Alice
@ -587,25 +587,25 @@ namespace transport
* payload = 4 ;
payload + + ; // size
memcpy ( payload , from . address ( ) . to_v4 ( ) . to_bytes ( ) . data ( ) , 4 ) ; // Alice's IP V4
payload + = 4 ; // address
payload + = 4 ; // address
}
else
{
* payload = 16 ;
payload + + ; // size
memcpy ( payload , from . address ( ) . to_v6 ( ) . to_bytes ( ) . data ( ) , 16 ) ; // Alice's IP V6
payload + = 16 ; // address
payload + = 16 ; // address
}
htobe16buf ( payload , from . port ( ) ) ; // Alice's port
payload + = 2 ; // port
htobe32buf ( payload , nonce ) ;
htobe32buf ( payload , nonce ) ;
if ( m_State = = eSessionStateEstablished )
{
{
// encrypt with session key
FillHeaderAndEncrypt ( PAYLOAD_TYPE_RELAY_RESPONSE , buf , isV4 ? 64 : 80 ) ;
Send ( buf , isV4 ? 64 : 80 ) ;
}
}
else
{
// ecrypt with Alice's intro key
@ -613,45 +613,45 @@ namespace transport
RAND_bytes ( iv , 16 ) ; // random iv
FillHeaderAndEncrypt ( PAYLOAD_TYPE_RELAY_RESPONSE , buf , isV4 ? 64 : 80 , introKey , iv , introKey ) ;
m_Server . Send ( buf , isV4 ? 64 : 80 , from ) ;
}
}
LogPrint ( eLogDebug , " SSU: relay response sent " ) ;
}
}
void SSUSession : : SendRelayIntro ( std : : shared_ptr < SSUSession > session , const boost : : asio : : ip : : udp : : endpoint & from )
{
if ( ! session ) return ;
if ( ! session ) return ;
// Alice's address always v4
if ( ! from . address ( ) . is_v4 ( ) )
{
LogPrint ( eLogWarning , " SSU: Alice's IP must be v4 " ) ;
return ;
}
}
uint8_t buf [ 48 + 18 ] = { 0 } ;
uint8_t * payload = buf + sizeof ( SSUHeader ) ;
* payload = 4 ;
payload + + ; // size
htobe32buf ( payload , from . address ( ) . to_v4 ( ) . to_ulong ( ) ) ; // Alice's IP
payload + = 4 ; // address
payload + = 4 ; // address
htobe16buf ( payload , from . port ( ) ) ; // Alice's port
payload + = 2 ; // port
* payload = 0 ; // challenge size
* payload = 0 ; // challenge size
uint8_t iv [ 16 ] ;
RAND_bytes ( iv , 16 ) ; // random iv
FillHeaderAndEncrypt ( PAYLOAD_TYPE_RELAY_INTRO , buf , 48 , session - > m_SessionKey , iv , session - > m_MacKey ) ;
m_Server . Send ( buf , 48 , session - > m_RemoteEndpoint ) ;
LogPrint ( eLogDebug , " SSU: relay intro sent " ) ;
}
void SSUSession : : ProcessRelayResponse ( const uint8_t * buf , size_t len )
{
LogPrint ( eLogDebug , " SSU message: Relay response received " ) ;
uint8_t remoteSize = * buf ;
LogPrint ( eLogDebug , " SSU message: Relay response received " ) ;
uint8_t remoteSize = * buf ;
buf + + ; // remote size
boost : : asio : : ip : : address_v4 remoteIP ( bufbe32toh ( buf ) ) ;
buf + = remoteSize ; // remote address
uint16_t remotePort = bufbe16toh ( buf ) ;
buf + = 2 ; // remote port
uint8_t ourSize = * buf ;
uint8_t ourSize = * buf ;
buf + + ; // our size
boost : : asio : : ip : : address ourIP ;
if ( ourSize = = 4 )
@ -675,7 +675,7 @@ namespace transport
buf + = 4 ; // nonce
auto it = m_RelayRequests . find ( nonce ) ;
if ( it ! = m_RelayRequests . end ( ) )
{
{
// check if we are waiting for introduction
boost : : asio : : ip : : udp : : endpoint remoteEndpoint ( remoteIP , remotePort ) ;
if ( ! m_Server . FindSession ( remoteEndpoint ) )
@ -686,10 +686,10 @@ namespace transport
if ( i2p : : context . GetRouterInfo ( ) . UsesIntroducer ( ) ) // if we are unreachable
m_Server . Send ( buf , 0 , remoteEndpoint ) ; // send HolePunch
m_Server . CreateDirectSession ( it - > second , remoteEndpoint , false ) ;
}
}
// delete request
m_RelayRequests . erase ( it ) ;
}
}
else
LogPrint ( eLogError , " SSU: Unsolicited RelayResponse, nonce= " , nonce ) ;
}
@ -708,11 +708,11 @@ namespace transport
}
else
LogPrint ( eLogWarning , " SSU: Address size " , size , " is not supported " ) ;
}
}
void SSUSession : : FillHeaderAndEncrypt ( uint8_t payloadType , uint8_t * buf , size_t len ,
void SSUSession : : FillHeaderAndEncrypt ( uint8_t payloadType , uint8_t * buf , size_t len ,
const i2p : : crypto : : AESKey & aesKey , const uint8_t * iv , const i2p : : crypto : : MACKey & macKey , uint8_t flag )
{
{
if ( len < sizeof ( SSUHeader ) )
{
LogPrint ( eLogError , " SSU: Unexpected packet length " , len ) ;
@ -753,18 +753,18 @@ namespace transport
memcpy ( buf + len , header - > iv , 16 ) ;
htobe16buf ( buf + len + 16 , encryptedLen ) ;
i2p : : crypto : : HMACMD5Digest ( encrypted , encryptedLen + 18 , m_MacKey , header - > mac ) ;
}
}
void SSUSession : : Decrypt ( uint8_t * buf , size_t len , const i2p : : crypto : : AESKey & aesKey )
{
if ( len < sizeof ( SSUHeader ) )
{
LogPrint ( eLogError , " SSU: Unexpected packet length " , len ) ;
return ;
}
}
SSUHeader * header = ( SSUHeader * ) buf ;
uint8_t * encrypted = & header - > flag ;
uint16_t encryptedLen = len - ( encrypted - buf ) ;
uint16_t encryptedLen = len - ( encrypted - buf ) ;
i2p : : crypto : : CBCDecryption decryption ;
decryption . SetKey ( aesKey ) ;
decryption . SetIV ( header - > iv ) ;
@ -777,24 +777,24 @@ namespace transport
{
LogPrint ( eLogError , " SSU: Unexpected packet length " , len ) ;
return ;
}
}
SSUHeader * header = ( SSUHeader * ) buf ;
uint8_t * encrypted = & header - > flag ;
uint16_t encryptedLen = len - ( encrypted - buf ) ;
uint16_t encryptedLen = len - ( encrypted - buf ) ;
if ( encryptedLen > 0 )
{
{
m_SessionKeyDecryption . SetIV ( header - > iv ) ;
m_SessionKeyDecryption . Decrypt ( encrypted , encryptedLen , encrypted ) ;
}
}
}
}
bool SSUSession : : Validate ( uint8_t * buf , size_t len , const i2p : : crypto : : MACKey & macKey )
{
if ( len < sizeof ( SSUHeader ) )
{
LogPrint ( eLogError , " SSU: Unexpected packet length " , len ) ;
return false ;
}
}
SSUHeader * header = ( SSUHeader * ) buf ;
uint8_t * encrypted = & header - > flag ;
uint16_t encryptedLen = len - ( encrypted - buf ) ;
@ -809,12 +809,12 @@ namespace transport
void SSUSession : : Connect ( )
{
if ( m_State = = eSessionStateUnknown )
{
{
// set connect timer
ScheduleConnectTimer ( ) ;
m_DHKeysPair = transports . GetNextDHKeysPair ( ) ;
SendSessionRequest ( ) ;
}
}
}
void SSUSession : : WaitForConnect ( )
@ -830,7 +830,7 @@ namespace transport
m_ConnectTimer . cancel ( ) ;
m_ConnectTimer . expires_from_now ( boost : : posix_time : : seconds ( SSU_CONNECT_TIMEOUT ) ) ;
m_ConnectTimer . async_wait ( std : : bind ( & SSUSession : : HandleConnectTimer ,
shared_from_this ( ) , std : : placeholders : : _1 ) ) ;
shared_from_this ( ) , std : : placeholders : : _1 ) ) ;
}
void SSUSession : : HandleConnectTimer ( const boost : : system : : error_code & ecode )
@ -840,14 +840,14 @@ namespace transport
// timeout expired
LogPrint ( eLogWarning , " SSU: session with " , m_RemoteEndpoint , " was not established after " , SSU_CONNECT_TIMEOUT , " seconds " ) ;
Failed ( ) ;
}
}
}
}
void SSUSession : : Introduce ( const i2p : : data : : RouterInfo : : Introducer & introducer ,
std : : shared_ptr < const i2p : : data : : RouterInfo > to )
{
if ( m_State = = eSessionStateUnknown )
{
{
// set connect timer
m_ConnectTimer . expires_from_now ( boost : : posix_time : : seconds ( SSU_CONNECT_TIMEOUT ) ) ;
m_ConnectTimer . async_wait ( std : : bind ( & SSUSession : : HandleConnectTimer ,
@ -865,7 +865,7 @@ namespace transport
// set connect timer
m_ConnectTimer . expires_from_now ( boost : : posix_time : : seconds ( SSU_CONNECT_TIMEOUT ) ) ;
m_ConnectTimer . async_wait ( std : : bind ( & SSUSession : : HandleConnectTimer ,
shared_from_this ( ) , std : : placeholders : : _1 ) ) ;
shared_from_this ( ) , std : : placeholders : : _1 ) ) ;
}
void SSUSession : : Close ( )
@ -873,7 +873,7 @@ namespace transport
SendSessionDestroyed ( ) ;
Reset ( ) ;
m_State = eSessionStateClosed ;
}
}
void SSUSession : : Reset ( )
{
@ -882,10 +882,10 @@ namespace transport
m_Data . Stop ( ) ;
m_ConnectTimer . cancel ( ) ;
if ( m_SentRelayTag )
{
{
m_Server . RemoveRelay ( m_SentRelayTag ) ; // relay tag is not valid anymore
m_SentRelayTag = 0 ;
}
}
m_DHKeysPair = nullptr ;
m_SignedData = nullptr ;
m_IsSessionKey = false ;
@ -908,20 +908,20 @@ namespace transport
if ( m_SentRelayTag )
m_Server . AddRelay ( m_SentRelayTag , shared_from_this ( ) ) ;
m_LastActivityTimestamp = i2p : : util : : GetSecondsSinceEpoch ( ) ;
}
}
void SSUSession : : Failed ( )
{
if ( m_State ! = eSessionStateFailed )
{
{
m_State = eSessionStateFailed ;
m_Server . DeleteSession ( shared_from_this ( ) ) ;
}
}
m_Server . DeleteSession ( shared_from_this ( ) ) ;
}
}
void SSUSession : : SendI2NPMessages ( const std : : vector < std : : shared_ptr < I2NPMessage > > & msgs )
{
GetService ( ) . post ( std : : bind ( & SSUSession : : PostI2NPMessages , shared_from_this ( ) , msgs ) ) ;
GetService ( ) . post ( std : : bind ( & SSUSession : : PostI2NPMessages , shared_from_this ( ) , msgs ) ) ;
}
void SSUSession : : PostI2NPMessages ( std : : vector < std : : shared_ptr < I2NPMessage > > msgs )
@ -931,7 +931,7 @@ namespace transport
for ( const auto & it : msgs )
if ( it ) m_Data . Send ( it ) ;
}
}
}
void SSUSession : : ProcessData ( uint8_t * buf , size_t len )
{
@ -942,29 +942,29 @@ namespace transport
void SSUSession : : FlushData ( )
{
if ( m_IsDataReceived )
{
{
m_Data . FlushReceivedMessage ( ) ;
m_IsDataReceived = false ;
}
}
}
void SSUSession : : ProcessPeerTest ( const uint8_t * buf , size_t len , const boost : : asio : : ip : : udp : : endpoint & senderEndpoint )
{
uint32_t nonce = bufbe32toh ( buf ) ; // 4 bytes
uint8_t size = buf [ 4 ] ; // 1 byte
uint8_t size = buf [ 4 ] ; // 1 byte
const uint8_t * address = buf + 5 ; // big endian, size bytes
uint16_t port = buf16toh ( buf + size + 5 ) ; // big endian, 2 bytes
const uint8_t * introKey = buf + size + 7 ;
if ( port & & ( size ! = 4 ) & & ( size ! = 16 ) )
if ( port & & ( size ! = 4 ) & & ( size ! = 16 ) )
{
LogPrint ( eLogWarning , " SSU: Address of " , size , " bytes not supported " ) ;
return ;
}
}
switch ( m_Server . GetPeerTestParticipant ( nonce ) )
{
// existing test
{
// existing test
case ePeerTestParticipantAlice1 :
{
{
if ( m_Server . GetPeerTestSession ( nonce ) = = shared_from_this ( ) ) // Alice-Bob
{
LogPrint ( eLogDebug , " SSU: peer test from Bob. We are Alice " ) ;
@ -981,7 +981,7 @@ namespace transport
SendPeerTest ( nonce , senderEndpoint . address ( ) , senderEndpoint . port ( ) , introKey , true , false ) ; // to Charlie
}
break ;
}
}
case ePeerTestParticipantAlice2 :
{
if ( m_Server . GetPeerTestSession ( nonce ) = = shared_from_this ( ) ) // Alice-Bob
@ -994,8 +994,8 @@ namespace transport
m_Server . RemovePeerTest ( nonce ) ;
}
break ;
}
case ePeerTestParticipantBob :
}
case ePeerTestParticipantBob :
{
LogPrint ( eLogDebug , " SSU: peer test from Charlie. We are Bob " ) ;
auto session = m_Server . GetPeerTestSession ( nonce ) ; // session with Alice from PeerTest
@ -1005,13 +1005,13 @@ namespace transport
break ;
}
case ePeerTestParticipantCharlie :
{
{
LogPrint ( eLogDebug , " SSU: peer test from Alice. We are Charlie " ) ;
SendPeerTest ( nonce , senderEndpoint . address ( ) , senderEndpoint . port ( ) , introKey ) ; // to Alice with her actual address
m_Server . RemovePeerTest ( nonce ) ; // nonce has been used
break ;
}
// test not found
// test not found
case ePeerTestParticipantUnknown :
{
if ( m_State = = eSessionStateEstablished )
@ -1034,7 +1034,7 @@ namespace transport
boost : : asio : : ip : : address_v6 : : bytes_type bytes ;
memcpy ( bytes . data ( ) , address , 16 ) ;
addr = boost : : asio : : ip : : address_v6 ( bytes ) ;
}
}
SendPeerTest ( nonce , addr , be16toh ( port ) , introKey ) ; // to Alice with her address received from Bob
}
else
@ -1044,26 +1044,26 @@ namespace transport
if ( session )
{
m_Server . NewPeerTest ( nonce , ePeerTestParticipantBob , shared_from_this ( ) ) ;
session - > SendPeerTest ( nonce , senderEndpoint . address ( ) , senderEndpoint . port ( ) , introKey , false ) ; // to Charlie with Alice's actual address
}
session - > SendPeerTest ( nonce , senderEndpoint . address ( ) , senderEndpoint . port ( ) , introKey , false ) ; // to Charlie with Alice's actual address
}
}
}
else
LogPrint ( eLogError , " SSU: unexpected peer test " ) ;
}
}
}
}
void SSUSession : : SendPeerTest ( uint32_t nonce , const boost : : asio : : ip : : address & address , uint16_t port ,
void SSUSession : : SendPeerTest ( uint32_t nonce , const boost : : asio : : ip : : address & address , uint16_t port ,
const uint8_t * introKey , bool toAddress , bool sendAddress )
// toAddress is true for Alice<->Chalie communications only
// sendAddress is false if message comes from Alice
// sendAddress is false if message comes from Alice
{
uint8_t buf [ 80 + 18 ] = { 0 } ;
uint8_t iv [ 16 ] ;
uint8_t * payload = buf + sizeof ( SSUHeader ) ;
htobe32buf ( payload , nonce ) ;
payload + = 4 ; // nonce
payload + = 4 ; // nonce
// address and port
if ( sendAddress )
{
@ -1075,11 +1075,11 @@ namespace transport
else if ( address . is_v6 ( ) )
{
* payload = 16 ;
memcpy ( payload + 1 , address . to_v6 ( ) . to_bytes ( ) . data ( ) , 16 ) ; // our IP V6
memcpy ( payload + 1 , address . to_v6 ( ) . to_bytes ( ) . data ( ) , 16 ) ; // our IP V6
}
else
* payload = 0 ;
payload + = ( payload [ 0 ] + 1 ) ;
payload + = ( payload [ 0 ] + 1 ) ;
}
else
{
@ -1096,27 +1096,27 @@ namespace transport
if ( addr )
memcpy ( payload , addr - > ssu - > key , 32 ) ; // intro key
else
LogPrint ( eLogInfo , " SSU is not supported. Can't send peer test " ) ;
}
else
LogPrint ( eLogInfo , " SSU is not supported. Can't send peer test " ) ;
}
else
memcpy ( payload , introKey , 32 ) ; // intro key
// send
// send
RAND_bytes ( iv , 16 ) ; // random iv
if ( toAddress )
{
{
// encrypt message with specified intro key
FillHeaderAndEncrypt ( PAYLOAD_TYPE_PEER_TEST , buf , 80 , introKey , iv , introKey ) ;
boost : : asio : : ip : : udp : : endpoint e ( address , port ) ;
m_Server . Send ( buf , 80 , e ) ;
}
}
else
{
// encrypt message with session key
FillHeaderAndEncrypt ( PAYLOAD_TYPE_PEER_TEST , buf , 80 ) ;
Send ( buf , 80 ) ;
}
}
}
void SSUSession : : SendPeerTest ( )
{
@ -1134,23 +1134,23 @@ namespace transport
m_IsPeerTest = false ;
m_Server . NewPeerTest ( nonce , ePeerTestParticipantAlice1 , shared_from_this ( ) ) ;
SendPeerTest ( nonce , boost : : asio : : ip : : address ( ) , 0 , address - > ssu - > key , false , false ) ; // address and port always zero for Alice
}
}
void SSUSession : : SendKeepAlive ( )
{
if ( m_State = = eSessionStateEstablished )
{
{
uint8_t buf [ 48 + 18 ] = { 0 } ;
uint8_t * payload = buf + sizeof ( SSUHeader ) ;
* payload = 0 ; // flags
payload + + ;
* payload = 0 ; // num fragments
* payload = 0 ; // num fragments
// encrypt message with session key
FillHeaderAndEncrypt ( PAYLOAD_TYPE_DATA , buf , 48 ) ;
Send ( buf , 48 ) ;
LogPrint ( eLogDebug , " SSU: keep-alive sent " ) ;
m_LastActivityTimestamp = i2p : : util : : GetSecondsSinceEpoch ( ) ;
}
}
}
void SSUSession : : SendSessionDestroyed ( )
@ -1170,31 +1170,31 @@ namespace transport
}
LogPrint ( eLogDebug , " SSU: session destroyed sent " ) ;
}
}
}
void SSUSession : : Send ( uint8_t type , const uint8_t * payload , size_t len )
{
uint8_t buf [ SSU_MTU_V4 + 18 ] = { 0 } ;
size_t msgSize = len + sizeof ( SSUHeader ) ;
size_t msgSize = len + sizeof ( SSUHeader ) ;
size_t paddingSize = msgSize & 0x0F ; // %16
if ( paddingSize > 0 ) msgSize + = ( 16 - paddingSize ) ;
if ( msgSize > SSU_MTU_V4 )
{
LogPrint ( eLogWarning , " SSU: payload size " , msgSize , " exceeds MTU " ) ;
return ;
}
}
memcpy ( buf + sizeof ( SSUHeader ) , payload , len ) ;
// encrypt message with session key
FillHeaderAndEncrypt ( type , buf , msgSize ) ;
Send ( buf , msgSize ) ;
}
}
void SSUSession : : Send ( const uint8_t * buf , size_t size )
{
m_NumSentBytes + = size ;
i2p : : transport : : transports . UpdateSentBytes ( size ) ;
m_Server . Send ( buf , size , m_RemoteEndpoint ) ;
}
}
}
}
yangfl
6 years ago