static int readPeerId( tr_handshake * handshake, struct evbuffer * inbuf ) { tr_bool peerIsGood; char client[128]; tr_torrent * tor; const uint8_t * tor_peer_id; uint8_t peer_id[PEER_ID_LEN]; if( evbuffer_get_length( inbuf ) < PEER_ID_LEN ) return READ_LATER; /* peer id */ tr_peerIoReadBytes( handshake->io, inbuf, peer_id, PEER_ID_LEN ); tr_peerIoSetPeersId( handshake->io, peer_id ); handshake->havePeerID = TRUE; tr_clientForId( client, sizeof( client ), peer_id ); dbgmsg( handshake, "peer-id is [%s] ... isIncoming is %d", client, tr_peerIoIsIncoming( handshake->io ) ); /* if we've somehow connected to ourselves, don't keep the connection */ tor = tr_torrentFindFromHash( handshake->session, tr_peerIoGetTorrentHash( handshake->io ) ); tor_peer_id = tor && tor->peer_id ? tor->peer_id : tr_getPeerId( ); peerIsGood = memcmp( peer_id, tor_peer_id, PEER_ID_LEN ) != 0; dbgmsg( handshake, "isPeerGood == %d", (int)peerIsGood ); return tr_handshakeDone( handshake, peerIsGood ); }
static int readPeerId (tr_handshake * handshake, struct evbuffer * inbuf) { bool connected_to_self; char client[128]; uint8_t peer_id[PEER_ID_LEN]; tr_torrent * tor; if (evbuffer_get_length (inbuf) < PEER_ID_LEN) return READ_LATER; /* peer id */ tr_peerIoReadBytes (handshake->io, inbuf, peer_id, PEER_ID_LEN); tr_peerIoSetPeersId (handshake->io, peer_id); handshake->havePeerID = true; tr_clientForId (client, sizeof (client), peer_id); dbgmsg (handshake, "peer-id is [%s] ... isIncoming is %d", client, tr_peerIoIsIncoming (handshake->io)); /* if we've somehow connected to ourselves, don't keep the connection */ tor = tr_torrentFindFromHash (handshake->session, tr_peerIoGetTorrentHash (handshake->io)); connected_to_self = (tor != NULL) && !memcmp (peer_id, tr_torrentGetPeerId(tor), PEER_ID_LEN); return tr_handshakeDone (handshake, !connected_to_self); }
int tr_peerIoReconnect( tr_peerIo * io ) { short int pendingEvents; tr_session * session; assert( tr_isPeerIo( io ) ); assert( !tr_peerIoIsIncoming( io ) ); session = tr_peerIoGetSession( io ); pendingEvents = io->pendingEvents; event_disable( io, EV_READ | EV_WRITE ); if( io->socket >= 0 ) tr_netClose( session, io->socket ); io->socket = tr_netOpenPeerSocket( session, &io->addr, io->port, io->isSeed ); event_set( &io->event_read, io->socket, EV_READ, event_read_cb, io ); event_set( &io->event_write, io->socket, EV_WRITE, event_write_cb, io ); if( io->socket >= 0 ) { event_enable( io, pendingEvents ); tr_netSetTOS( io->socket, session->peerSocketTOS ); maybeSetCongestionAlgorithm( io->socket, session->peer_congestion_algorithm ); return 0; } return -1; }
tr_handshake* tr_handshakeNew (tr_peerIo * io, tr_encryption_mode encryptionMode, handshakeDoneCB doneCB, void * doneUserData) { tr_handshake * handshake; tr_session * session = tr_peerIoGetSession (io); handshake = tr_new0 (tr_handshake, 1); handshake->io = io; handshake->crypto = tr_peerIoGetCrypto (io); handshake->encryptionMode = encryptionMode; handshake->doneCB = doneCB; handshake->doneUserData = doneUserData; handshake->session = session; handshake->timeout_timer = evtimer_new (session->event_base, handshakeTimeout, handshake); tr_timerAdd (handshake->timeout_timer, HANDSHAKE_TIMEOUT_SEC, 0); tr_peerIoRef (io); /* balanced by the unref in tr_handshakeFree */ tr_peerIoSetIOFuncs (handshake->io, canRead, NULL, gotError, handshake); tr_peerIoSetEncryption (io, PEER_ENCRYPTION_NONE); if (tr_peerIoIsIncoming (handshake->io)) { setReadState (handshake, AWAITING_HANDSHAKE); } else if (encryptionMode != TR_CLEAR_PREFERRED) { sendYa (handshake); } else { uint8_t msg[HANDSHAKE_SIZE]; buildHandshakeMessage (handshake, msg); handshake->haveSentBitTorrentHandshake = 1; setReadState (handshake, AWAITING_HANDSHAKE); tr_peerIoWriteBytes (handshake->io, msg, sizeof (msg), false); } return handshake; }
static int readHandshake( tr_handshake * handshake, struct evbuffer * inbuf ) { uint8_t pstrlen; uint8_t * pstr; uint8_t reserved[HANDSHAKE_FLAGS_LEN]; uint8_t hash[SHA_DIGEST_LENGTH]; dbgmsg( handshake, "payload: need %d, got %zu", INCOMING_HANDSHAKE_LEN, evbuffer_get_length( inbuf ) ); if( evbuffer_get_length( inbuf ) < INCOMING_HANDSHAKE_LEN ) return READ_LATER; handshake->haveReadAnythingFromPeer = TRUE; pstrlen = evbuffer_pullup( inbuf, 1 )[0]; /* peek, don't read. We may be handing inbuf to AWAITING_YA */ if( pstrlen == 19 ) /* unencrypted */ { tr_peerIoSetEncryption( handshake->io, PEER_ENCRYPTION_NONE ); if( handshake->encryptionMode == TR_ENCRYPTION_REQUIRED ) { dbgmsg( handshake, "peer is unencrypted, and we're disallowing that" ); return tr_handshakeDone( handshake, FALSE ); } } else /* encrypted or corrupt */ { tr_peerIoSetEncryption( handshake->io, PEER_ENCRYPTION_RC4 ); if( tr_peerIoIsIncoming( handshake->io ) ) { dbgmsg( handshake, "I think peer is sending us an encrypted handshake..." ); setState( handshake, AWAITING_YA ); return READ_NOW; } tr_cryptoDecrypt( handshake->crypto, 1, &pstrlen, &pstrlen ); if( pstrlen != 19 ) { dbgmsg( handshake, "I think peer has sent us a corrupt handshake..." ); return tr_handshakeDone( handshake, FALSE ); } } evbuffer_drain( inbuf, 1 ); /* pstr (BitTorrent) */ pstr = tr_new( uint8_t, pstrlen + 1 ); tr_peerIoReadBytes( handshake->io, inbuf, pstr, pstrlen ); pstr[pstrlen] = '\0'; if( strcmp( (char*)pstr, "BitTorrent protocol" ) ) { tr_free( pstr ); return tr_handshakeDone( handshake, FALSE ); } tr_free( pstr ); /* reserved bytes */ tr_peerIoReadBytes( handshake->io, inbuf, reserved, sizeof( reserved ) ); /** *** Extensions **/ tr_peerIoEnableLTEP( handshake->io, HANDSHAKE_HAS_LTEP( reserved ) ); tr_peerIoEnableFEXT( handshake->io, HANDSHAKE_HAS_FASTEXT( reserved ) ); tr_peerIoEnableDHT( handshake->io, HANDSHAKE_HAS_DHT( reserved ) ); /* torrent hash */ tr_peerIoReadBytes( handshake->io, inbuf, hash, sizeof( hash ) ); if( tr_peerIoIsIncoming( handshake->io ) ) { if( !tr_torrentExists( handshake->session, hash ) ) { dbgmsg( handshake, "peer is trying to connect to us for a torrent we don't have." ); return tr_handshakeDone( handshake, FALSE ); } else { assert( !tr_peerIoHasTorrentHash( handshake->io ) ); tr_peerIoSetTorrentHash( handshake->io, hash ); } } else /* outgoing */ { assert( tr_peerIoHasTorrentHash( handshake->io ) ); if( memcmp( hash, tr_peerIoGetTorrentHash( handshake->io ), SHA_DIGEST_LENGTH ) ) { dbgmsg( handshake, "peer returned the wrong hash. wtf?" ); return tr_handshakeDone( handshake, FALSE ); } } /** *** If it's an incoming message, we need to send a response handshake **/ if( !handshake->haveSentBitTorrentHandshake ) { uint8_t msg[HANDSHAKE_SIZE]; buildHandshakeMessage( handshake, msg ); tr_peerIoWriteBytes( handshake->io, msg, sizeof( msg ), FALSE ); handshake->haveSentBitTorrentHandshake = 1; } setReadState( handshake, AWAITING_PEER_ID ); return READ_NOW; }