/* * This file Copyright (C) 2007-2009 Charles Kerr * * This file is licensed by the GPL version 2. Works owned by the * Transmission project are granted a special exemption to clause 2(b) * so that the bulk of its code can remain under the MIT license. * This exemption does not extend to derived works not owned by * the Transmission project. * * $Id$ */ #include #include #include /* memcpy, memcmp, strstr */ #include /* qsort */ #include /* INT_MAX */ #include #include "transmission.h" #include "session.h" #include "bandwidth.h" #include "bencode.h" #include "blocklist.h" #include "clients.h" #include "completion.h" #include "crypto.h" #include "fdlimit.h" #include "handshake.h" #include "inout.h" /* tr_ioTestPiece */ #include "net.h" #include "peer-io.h" #include "peer-mgr.h" #include "peer-msgs.h" #include "ptrarray.h" #include "stats.h" /* tr_statsAddUploaded, tr_statsAddDownloaded */ #include "torrent.h" #include "trevent.h" #include "utils.h" #include "webseed.h" enum { /* how frequently to change which peers are choked */ RECHOKE_PERIOD_MSEC = ( 10 * 1000 ), /* minimum interval for refilling peers' request lists */ REFILL_PERIOD_MSEC = 400, /* how frequently to reallocate bandwidth */ BANDWIDTH_PERIOD_MSEC = 500, /* how frequently to age out old piece request lists */ REFILL_UPKEEP_PERIOD_MSEC = 10000, /* how frequently to decide which peers live and die */ RECONNECT_PERIOD_MSEC = 500, /* when many peers are available, keep idle ones this long */ MIN_UPLOAD_IDLE_SECS = ( 30 ), /* when few peers are available, keep idle ones this long */ MAX_UPLOAD_IDLE_SECS = ( 60 * 5 ), /* max # of peers to ask fer per torrent per reconnect pulse */ MAX_RECONNECTIONS_PER_PULSE = 16, /* max number of peers to ask for per second overall. * this throttle is to avoid overloading the router */ MAX_CONNECTIONS_PER_SECOND = 32, /* number of bad pieces a peer is allowed to send before we ban them */ MAX_BAD_PIECES_PER_PEER = 5, /* amount of time to keep a list of request pieces lying around before it's considered too old and needs to be rebuilt */ PIECE_LIST_SHELF_LIFE_SECS = 60, /* use for bitwise operations w/peer_atom.myflags */ MYFLAG_BANNED = 1, /* use for bitwise operations w/peer_atom.myflags */ /* unreachable for now... but not banned. * if they try to connect to us it's okay */ MYFLAG_UNREACHABLE = 2, /* the minimum we'll wait before attempting to reconnect to a peer */ MINIMUM_RECONNECT_INTERVAL_SECS = 5 }; /** *** **/ enum { UPLOAD_ONLY_UKNOWN, UPLOAD_ONLY_YES, UPLOAD_ONLY_NO }; /** * Peer information that should be kept even before we've connected and * after we've disconnected. These are kept in a pool of peer_atoms to decide * which ones would make good candidates for connecting to, and to watch out * for banned peers. * * @see tr_peer * @see tr_peermsgs */ struct peer_atom { uint8_t from; uint8_t flags; /* these match the added_f flags */ uint8_t myflags; /* flags that aren't defined in added_f */ uint8_t uploadOnly; /* UPLOAD_ONLY_ */ tr_port port; uint16_t numFails; tr_address addr; time_t time; /* when the peer's connection status last changed */ time_t piece_data_time; }; struct tr_blockIterator { time_t expirationDate; struct tr_torrent_peers * t; tr_block_index_t blockIndex, blockCount, *blocks; tr_piece_index_t pieceIndex, pieceCount, *pieces; }; typedef struct tr_torrent_peers { tr_bool isRunning; uint8_t hash[SHA_DIGEST_LENGTH]; int * pendingRequestCount; tr_ptrArray outgoingHandshakes; /* tr_handshake */ tr_ptrArray pool; /* struct peer_atom */ tr_ptrArray peers; /* tr_peer */ tr_ptrArray webseeds; /* tr_webseed */ tr_timer * refillTimer; tr_torrent * tor; tr_peer * optimistic; /* the optimistic peer, or NULL if none */ struct tr_blockIterator * refillQueue; /* used in refillPulse() */ struct tr_peerMgr * manager; } Torrent; struct tr_peerMgr { tr_session * session; tr_ptrArray incomingHandshakes; /* tr_handshake */ tr_timer * bandwidthTimer; tr_timer * rechokeTimer; tr_timer * reconnectTimer; tr_timer * refillUpkeepTimer; }; #define tordbg( t, ... ) \ do { \ if( tr_deepLoggingIsActive( ) ) \ tr_deepLog( __FILE__, __LINE__, t->tor->info.name, __VA_ARGS__ ); \ } while( 0 ) #define dbgmsg( ... ) \ do { \ if( tr_deepLoggingIsActive( ) ) \ tr_deepLog( __FILE__, __LINE__, NULL, __VA_ARGS__ ); \ } while( 0 ) /** *** **/ static TR_INLINE void managerLock( const struct tr_peerMgr * manager ) { tr_globalLock( manager->session ); } static TR_INLINE void managerUnlock( const struct tr_peerMgr * manager ) { tr_globalUnlock( manager->session ); } static TR_INLINE void torrentLock( Torrent * torrent ) { managerLock( torrent->manager ); } static TR_INLINE void torrentUnlock( Torrent * torrent ) { managerUnlock( torrent->manager ); } static TR_INLINE int torrentIsLocked( const Torrent * t ) { return tr_globalIsLocked( t->manager->session ); } /** *** **/ static int handshakeCompareToAddr( const void * va, const void * vb ) { const tr_handshake * a = va; return tr_compareAddresses( tr_handshakeGetAddr( a, NULL ), vb ); } static int handshakeCompare( const void * a, const void * b ) { return handshakeCompareToAddr( a, tr_handshakeGetAddr( b, NULL ) ); } static tr_handshake* getExistingHandshake( tr_ptrArray * handshakes, const tr_address * addr ) { return tr_ptrArrayFindSorted( handshakes, addr, handshakeCompareToAddr ); } static int comparePeerAtomToAddress( const void * va, const void * vb ) { const struct peer_atom * a = va; return tr_compareAddresses( &a->addr, vb ); } static int comparePeerAtoms( const void * va, const void * vb ) { const struct peer_atom * b = vb; return comparePeerAtomToAddress( va, &b->addr ); } /** *** **/ static Torrent* getExistingTorrent( tr_peerMgr * manager, const uint8_t * hash ) { tr_torrent * tor = tr_torrentFindFromHash( manager->session, hash ); return tor == NULL ? NULL : tor->torrentPeers; } static int peerCompare( const void * va, const void * vb ) { const tr_peer * a = va; const tr_peer * b = vb; return tr_compareAddresses( &a->addr, &b->addr ); } static int peerCompareToAddr( const void * va, const void * vb ) { const tr_peer * a = va; return tr_compareAddresses( &a->addr, vb ); } static tr_peer* getExistingPeer( Torrent * torrent, const tr_address * addr ) { assert( torrentIsLocked( torrent ) ); assert( addr ); return tr_ptrArrayFindSorted( &torrent->peers, addr, peerCompareToAddr ); } static struct peer_atom* getExistingAtom( const Torrent * t, const tr_address * addr ) { Torrent * tt = (Torrent*)t; assert( torrentIsLocked( t ) ); return tr_ptrArrayFindSorted( &tt->pool, addr, comparePeerAtomToAddress ); } static tr_bool peerIsInUse( const Torrent * ct, const tr_address * addr ) { Torrent * t = (Torrent*) ct; assert( torrentIsLocked ( t ) ); return getExistingPeer( t, addr ) || getExistingHandshake( &t->outgoingHandshakes, addr ) || getExistingHandshake( &t->manager->incomingHandshakes, addr ); } static tr_peer* peerConstructor( const tr_address * addr ) { tr_peer * p; p = tr_new0( tr_peer, 1 ); p->addr = *addr; return p; } static tr_peer* getPeer( Torrent * torrent, const tr_address * addr ) { tr_peer * peer; assert( torrentIsLocked( torrent ) ); peer = getExistingPeer( torrent, addr ); if( peer == NULL ) { peer = peerConstructor( addr ); tr_ptrArrayInsertSorted( &torrent->peers, peer, peerCompare ); } return peer; } static void peerDestructor( tr_peer * peer ) { assert( peer ); if( peer->msgs != NULL ) { tr_peerMsgsUnsubscribe( peer->msgs, peer->msgsTag ); tr_peerMsgsFree( peer->msgs ); } tr_peerIoClear( peer->io ); tr_peerIoUnref( peer->io ); /* balanced by the ref in handshakeDoneCB() */ tr_bitfieldFree( peer->have ); tr_bitfieldFree( peer->blame ); tr_free( peer->client ); tr_free( peer ); } static void removePeer( Torrent * t, tr_peer * peer ) { tr_peer * removed; struct peer_atom * atom = peer->atom; assert( torrentIsLocked( t ) ); assert( atom ); atom->time = time( NULL ); removed = tr_ptrArrayRemoveSorted( &t->peers, peer, peerCompare ); assert( removed == peer ); peerDestructor( removed ); } static void removeAllPeers( Torrent * t ) { while( !tr_ptrArrayEmpty( &t->peers ) ) removePeer( t, tr_ptrArrayNth( &t->peers, 0 ) ); } static void blockIteratorFree( struct tr_blockIterator ** inout ); static void torrentDestructor( void * vt ) { Torrent * t = vt; uint8_t hash[SHA_DIGEST_LENGTH]; assert( t ); assert( !t->isRunning ); assert( torrentIsLocked( t ) ); assert( tr_ptrArrayEmpty( &t->outgoingHandshakes ) ); assert( tr_ptrArrayEmpty( &t->peers ) ); memcpy( hash, t->hash, SHA_DIGEST_LENGTH ); tr_timerFree( &t->refillTimer ); blockIteratorFree( &t->refillQueue ); tr_ptrArrayDestruct( &t->webseeds, (PtrArrayForeachFunc)tr_webseedFree ); tr_ptrArrayDestruct( &t->pool, (PtrArrayForeachFunc)tr_free ); tr_ptrArrayDestruct( &t->outgoingHandshakes, NULL ); tr_ptrArrayDestruct( &t->peers, NULL ); tr_free( t->pendingRequestCount ); tr_free( t ); } static void peerCallbackFunc( void * vpeer, void * vevent, void * vt ); static Torrent* torrentConstructor( tr_peerMgr * manager, tr_torrent * tor ) { int i; Torrent * t; t = tr_new0( Torrent, 1 ); t->manager = manager; t->tor = tor; t->pool = TR_PTR_ARRAY_INIT; t->peers = TR_PTR_ARRAY_INIT; t->webseeds = TR_PTR_ARRAY_INIT; t->outgoingHandshakes = TR_PTR_ARRAY_INIT; memcpy( t->hash, tor->info.hash, SHA_DIGEST_LENGTH ); for( i = 0; i < tor->info.webseedCount; ++i ) { tr_webseed * w = tr_webseedNew( tor, tor->info.webseeds[i], peerCallbackFunc, t ); tr_ptrArrayAppend( &t->webseeds, w ); } return t; } static int bandwidthPulse ( void * vmgr ); static int rechokePulse ( void * vmgr ); static int reconnectPulse ( void * vmgr ); static int refillUpkeep ( void * vmgr ); tr_peerMgr* tr_peerMgrNew( tr_session * session ) { tr_peerMgr * m = tr_new0( tr_peerMgr, 1 ); m->session = session; m->incomingHandshakes = TR_PTR_ARRAY_INIT; m->bandwidthTimer = tr_timerNew( session, bandwidthPulse, m, BANDWIDTH_PERIOD_MSEC ); m->rechokeTimer = tr_timerNew( session, rechokePulse, m, RECHOKE_PERIOD_MSEC ); m->reconnectTimer = tr_timerNew( session, reconnectPulse, m, RECONNECT_PERIOD_MSEC ); m->refillUpkeepTimer = tr_timerNew( session, refillUpkeep, m, REFILL_UPKEEP_PERIOD_MSEC ); rechokePulse( m ); return m; } void tr_peerMgrFree( tr_peerMgr * manager ) { managerLock( manager ); tr_timerFree( &manager->refillUpkeepTimer ); tr_timerFree( &manager->reconnectTimer ); tr_timerFree( &manager->rechokeTimer ); tr_timerFree( &manager->bandwidthTimer ); /* free the handshakes. Abort invokes handshakeDoneCB(), which removes * the item from manager->handshakes, so this is a little roundabout... */ while( !tr_ptrArrayEmpty( &manager->incomingHandshakes ) ) tr_handshakeAbort( tr_ptrArrayNth( &manager->incomingHandshakes, 0 ) ); tr_ptrArrayDestruct( &manager->incomingHandshakes, NULL ); managerUnlock( manager ); tr_free( manager ); } static int clientIsDownloadingFrom( const tr_peer * peer ) { return peer->clientIsInterested && !peer->clientIsChoked; } static int clientIsUploadingTo( const tr_peer * peer ) { return peer->peerIsInterested && !peer->peerIsChoked; } /*** **** ***/ tr_bool tr_peerMgrPeerIsSeed( const tr_torrent * tor, const tr_address * addr ) { tr_bool isSeed = FALSE; const Torrent * t = tor->torrentPeers; const struct peer_atom * atom = getExistingAtom( t, addr ); if( atom ) isSeed = ( atom->flags & ADDED_F_SEED_FLAG ) != 0; return isSeed; } /**** ***** ***** REFILL ***** ****/ static void assertValidPiece( Torrent * t, tr_piece_index_t piece ) { assert( t ); assert( t->tor ); assert( piece < t->tor->info.pieceCount ); } static int getPieceRequests( Torrent * t, tr_piece_index_t piece ) { assertValidPiece( t, piece ); return t->pendingRequestCount ? t->pendingRequestCount[piece] : 0; } static void incrementPieceRequests( Torrent * t, tr_piece_index_t piece ) { assertValidPiece( t, piece ); if( t->pendingRequestCount == NULL ) t->pendingRequestCount = tr_new0( int, t->tor->info.pieceCount ); t->pendingRequestCount[piece]++; } static void decrementPieceRequests( Torrent * t, tr_piece_index_t piece ) { assertValidPiece( t, piece ); if( t->pendingRequestCount ) t->pendingRequestCount[piece]--; } struct tr_refill_piece { tr_priority_t priority; uint32_t piece; uint32_t peerCount; int random; int pendingRequestCount; int missingBlockCount; }; static int compareRefillPiece( const void * aIn, const void * bIn ) { const struct tr_refill_piece * a = aIn; const struct tr_refill_piece * b = bIn; /* if one piece has a higher priority, it goes first */ if( a->priority != b->priority ) return a->priority > b->priority ? -1 : 1; /* have a per-priority endgame */ if( a->pendingRequestCount != b->pendingRequestCount ) return a->pendingRequestCount < b->pendingRequestCount ? -1 : 1; /* fewer missing pieces goes first */ if( a->missingBlockCount != b->missingBlockCount ) return a->missingBlockCount < b->missingBlockCount ? -1 : 1; /* otherwise if one has fewer peers, it goes first */ if( a->peerCount != b->peerCount ) return a->peerCount < b->peerCount ? -1 : 1; /* otherwise go with our random seed */ if( a->random != b->random ) return a->random < b->random ? -1 : 1; return 0; } static tr_piece_index_t * getPreferredPieces( Torrent * t, tr_piece_index_t * pieceCount ) { const tr_torrent * tor = t->tor; const tr_info * inf = &tor->info; tr_piece_index_t i; tr_piece_index_t poolSize = 0; tr_piece_index_t * pool = tr_new( tr_piece_index_t , inf->pieceCount ); int peerCount; const tr_peer ** peers; assert( torrentIsLocked( t ) ); peers = (const tr_peer**) tr_ptrArrayBase( &t->peers ); peerCount = tr_ptrArraySize( &t->peers ); /* make a list of the pieces that we want but don't have */ for( i = 0; i < inf->pieceCount; ++i ) if( !tor->info.pieces[i].dnd && !tr_cpPieceIsComplete( &tor->completion, i ) ) pool[poolSize++] = i; /* sort the pool by which to request next */ if( poolSize > 1 ) { tr_piece_index_t j; struct tr_refill_piece * p = tr_new( struct tr_refill_piece, poolSize ); for( j = 0; j < poolSize; ++j ) { int k; const tr_piece_index_t piece = pool[j]; struct tr_refill_piece * setme = p + j; setme->piece = piece; setme->priority = inf->pieces[piece].priority; setme->peerCount = 0; setme->random = tr_cryptoWeakRandInt( INT_MAX ); setme->pendingRequestCount = getPieceRequests( t, piece ); setme->missingBlockCount = tr_cpMissingBlocksInPiece( &tor->completion, piece ); for( k = 0; k < peerCount; ++k ) { const tr_peer * peer = peers[k]; if( peer->peerIsInterested && !peer->clientIsChoked && tr_bitfieldHas( peer->have, piece ) ) ++setme->peerCount; } } qsort( p, poolSize, sizeof( struct tr_refill_piece ), compareRefillPiece ); for( j = 0; j < poolSize; ++j ) pool[j] = p[j].piece; tr_free( p ); } *pieceCount = poolSize; return pool; } static struct tr_blockIterator* blockIteratorNew( Torrent * t ) { struct tr_blockIterator * i = tr_new0( struct tr_blockIterator, 1 ); i->expirationDate = time( NULL ) + PIECE_LIST_SHELF_LIFE_SECS; i->t = t; i->pieces = getPreferredPieces( t, &i->pieceCount ); i->blocks = tr_new0( tr_block_index_t, t->tor->blockCountInPiece ); tordbg( t, "creating new refill queue.. it contains %"PRIu32" pieces", i->pieceCount ); return i; } static tr_bool blockIteratorNext( struct tr_blockIterator * i, tr_block_index_t * setme ) { tr_bool found; Torrent * t = i->t; tr_torrent * tor = t->tor; while( ( i->blockIndex == i->blockCount ) && ( i->pieceIndex < i->pieceCount ) ) { const tr_piece_index_t index = i->pieces[i->pieceIndex++]; const tr_block_index_t b = tr_torPieceFirstBlock( tor, index ); const tr_block_index_t e = b + tr_torPieceCountBlocks( tor, index ); tr_block_index_t block; assert( index < tor->info.pieceCount ); i->blockCount = 0; i->blockIndex = 0; for( block=b; block!=e; ++block ) if( !tr_cpBlockIsCompleteFast( &tor->completion, block ) ) i->blocks[i->blockCount++] = block; } assert( i->blockCount <= tor->blockCountInPiece ); if(( found = ( i->blockIndex < i->blockCount ))) *setme = i->blocks[i->blockIndex++]; return found; } static void blockIteratorSkipCurrentPiece( struct tr_blockIterator * i ) { i->blockIndex = i->blockCount; } static void blockIteratorFree( struct tr_blockIterator ** inout ) { struct tr_blockIterator * it = *inout; if( it != NULL ) { tr_free( it->blocks ); tr_free( it->pieces ); tr_free( it ); } *inout = NULL; } static tr_peer** getPeersUploadingToClient( Torrent * t, int * setmeCount ) { int j; int peerCount = 0; int retCount = 0; tr_peer ** peers = (tr_peer **) tr_ptrArrayPeek( &t->peers, &peerCount ); tr_peer ** ret = tr_new( tr_peer *, peerCount ); j = 0; /* this is a temporary test to make sure we walk through all the peers */ if( peerCount ) { /* Get a list of peers we're downloading from. Pick a different starting point each time so all peers get a chance at being the first in line */ const int fencepost = tr_cryptoWeakRandInt( peerCount ); int i = fencepost; do { if( clientIsDownloadingFrom( peers[i] ) ) ret[retCount++] = peers[i]; i = ( i + 1 ) % peerCount; ++j; } while( i != fencepost ); } assert( j == peerCount ); *setmeCount = retCount; return ret; } static uint32_t getBlockOffsetInPiece( const tr_torrent * tor, uint64_t b ) { const uint64_t piecePos = tor->info.pieceSize * tr_torBlockPiece( tor, b ); const uint64_t blockPos = tor->blockSize * b; assert( blockPos >= piecePos ); return (uint32_t)( blockPos - piecePos ); } static int refillUpkeep( void * vmgr ) { tr_torrent * tor = NULL; tr_peerMgr * mgr = vmgr; time_t now; managerLock( mgr ); now = time( NULL ); while(( tor = tr_torrentNext( mgr->session, tor ))) { Torrent * t = tor->torrentPeers; if( t && t->refillQueue && ( t->refillQueue->expirationDate <= now ) ) { tordbg( t, "refill queue is past its shelf date; discarding." ); blockIteratorFree( &t->refillQueue ); } } managerUnlock( mgr ); return TRUE; } static int refillPulse( void * vtorrent ) { tr_block_index_t block; int peerCount; int webseedCount; tr_peer ** peers; tr_webseed ** webseeds; Torrent * t = vtorrent; tr_torrent * tor = t->tor; tr_bool hasNext = TRUE; if( !t->isRunning ) return TRUE; if( tr_torrentIsSeed( t->tor ) ) return TRUE; torrentLock( t ); tordbg( t, "Refilling Request Buffers..." ); if( t->refillQueue == NULL ) t->refillQueue = blockIteratorNew( t ); peers = getPeersUploadingToClient( t, &peerCount ); webseedCount = tr_ptrArraySize( &t->webseeds ); webseeds = tr_memdup( tr_ptrArrayBase( &t->webseeds ), webseedCount * sizeof( tr_webseed* ) ); while( ( webseedCount || peerCount ) && (( hasNext = blockIteratorNext( t->refillQueue, &block ))) ) { int j; tr_bool handled = FALSE; const tr_piece_index_t index = tr_torBlockPiece( tor, block ); const uint32_t offset = getBlockOffsetInPiece( tor, block ); const uint32_t length = tr_torBlockCountBytes( tor, block ); assert( block < tor->blockCount ); /* find a peer who can ask for this block */ for( j=0; !handled && jmsgs, index, offset, length ); switch( val ) { case TR_ADDREQ_FULL: case TR_ADDREQ_CLIENT_CHOKED: peers[j] = peers[--peerCount]; break; case TR_ADDREQ_MISSING: case TR_ADDREQ_DUPLICATE: ++j; break; case TR_ADDREQ_OK: incrementPieceRequests( t, index ); handled = TRUE; break; default: assert( 0 && "unhandled value" ); break; } } /* maybe one of the webseeds can do it */ for( j=0; !handled && jrefillQueue ); } /* cleanup */ tr_free( webseeds ); tr_free( peers ); if( !hasNext ) { tordbg( t, "refill queue has no more blocks to request... freeing (webseed count: %d, peer count: %d)", webseedCount, peerCount ); blockIteratorFree( &t->refillQueue ); } t->refillTimer = NULL; torrentUnlock( t ); return FALSE; } static void broadcastGotBlock( Torrent * t, uint32_t index, uint32_t offset, uint32_t length ) { size_t i; size_t peerCount; tr_peer ** peers; assert( torrentIsLocked( t ) ); tordbg( t, "got a block; cancelling any duplicate requests from peers %"PRIu32":%"PRIu32"->%"PRIu32, index, offset, length ); peerCount = tr_ptrArraySize( &t->peers ); peers = (tr_peer**) tr_ptrArrayBase( &t->peers ); for( i=0; imsgs ) tr_peerMsgsCancel( peers[i]->msgs, index, offset, length ); } static void addStrike( Torrent * t, tr_peer * peer ) { tordbg( t, "increasing peer %s strike count to %d", tr_peerIoAddrStr( &peer->addr, peer->port ), peer->strikes + 1 ); if( ++peer->strikes >= MAX_BAD_PIECES_PER_PEER ) { struct peer_atom * atom = peer->atom; atom->myflags |= MYFLAG_BANNED; peer->doPurge = 1; tordbg( t, "banning peer %s", tr_peerIoAddrStr( &atom->addr, atom->port ) ); } } static void gotBadPiece( Torrent * t, tr_piece_index_t pieceIndex ) { tr_torrent * tor = t->tor; const uint32_t byteCount = tr_torPieceCountBytes( tor, pieceIndex ); tor->corruptCur += byteCount; tor->downloadedCur -= MIN( tor->downloadedCur, byteCount ); } static void refillSoon( Torrent * t ) { if( t->refillTimer == NULL ) t->refillTimer = tr_timerNew( t->manager->session, refillPulse, t, REFILL_PERIOD_MSEC ); } static void peerSuggestedPiece( Torrent * t UNUSED, tr_peer * peer UNUSED, tr_piece_index_t pieceIndex UNUSED, int isFastAllowed UNUSED ) { #if 0 assert( t ); assert( peer ); assert( peer->msgs ); /* is this a valid piece? */ if( pieceIndex >= t->tor->info.pieceCount ) return; /* don't ask for it if we've already got it */ if( tr_cpPieceIsComplete( t->tor->completion, pieceIndex ) ) return; /* don't ask for it if they don't have it */ if( !tr_bitfieldHas( peer->have, pieceIndex ) ) return; /* don't ask for it if we're choked and it's not fast */ if( !isFastAllowed && peer->clientIsChoked ) return; /* request the blocks that we don't have in this piece */ { tr_block_index_t block; const tr_torrent * tor = t->tor; const tr_block_index_t start = tr_torPieceFirstBlock( tor, pieceIndex ); const tr_block_index_t end = start + tr_torPieceCountBlocks( tor, pieceIndex ); for( block=start; blockcompletion, block ) ) { const uint32_t offset = getBlockOffsetInPiece( tor, block ); const uint32_t length = tr_torBlockCountBytes( tor, block ); tr_peerMsgsAddRequest( peer->msgs, pieceIndex, offset, length ); incrementPieceRequests( t, pieceIndex ); } } } #endif } static void peerCallbackFunc( void * vpeer, void * vevent, void * vt ) { tr_peer * peer = vpeer; /* may be NULL if peer is a webseed */ Torrent * t = vt; const tr_peer_event * e = vevent; torrentLock( t ); switch( e->eventType ) { case TR_PEER_UPLOAD_ONLY: /* update our atom */ if( peer ) peer->atom->uploadOnly = e->uploadOnly ? UPLOAD_ONLY_YES : UPLOAD_ONLY_NO; break; case TR_PEER_NEED_REQ: refillSoon( t ); break; case TR_PEER_CANCEL: decrementPieceRequests( t, e->pieceIndex ); break; case TR_PEER_PEER_GOT_DATA: { const time_t now = time( NULL ); tr_torrent * tor = t->tor; tr_torrentSetActivityDate( tor, now ); if( e->wasPieceData ) tor->uploadedCur += e->length; /* update the stats */ if( e->wasPieceData ) tr_statsAddUploaded( tor->session, e->length ); /* update our atom */ if( peer && e->wasPieceData ) peer->atom->piece_data_time = now; tor->needsSeedRatioCheck = TRUE; break; } case TR_PEER_CLIENT_GOT_SUGGEST: if( peer ) peerSuggestedPiece( t, peer, e->pieceIndex, FALSE ); break; case TR_PEER_CLIENT_GOT_ALLOWED_FAST: if( peer ) peerSuggestedPiece( t, peer, e->pieceIndex, TRUE ); break; case TR_PEER_CLIENT_GOT_DATA: { const time_t now = time( NULL ); tr_torrent * tor = t->tor; tr_torrentSetActivityDate( tor, now ); /* only add this to downloadedCur if we got it from a peer -- * webseeds shouldn't count against our ratio. As one tracker * admin put it, "Those pieces are downloaded directly from the * content distributor, not the peers, it is the tracker's job * to manage the swarms, not the web server and does not fit * into the jurisdiction of the tracker." */ if( peer && e->wasPieceData ) tor->downloadedCur += e->length; /* update the stats */ if( e->wasPieceData ) tr_statsAddDownloaded( tor->session, e->length ); /* update our atom */ if( peer && e->wasPieceData ) peer->atom->piece_data_time = now; break; } case TR_PEER_PEER_PROGRESS: { if( peer ) { struct peer_atom * atom = peer->atom; const int peerIsSeed = e->progress >= 1.0; if( peerIsSeed ) { tordbg( t, "marking peer %s as a seed", tr_peerIoAddrStr( &atom->addr, atom->port ) ); atom->flags |= ADDED_F_SEED_FLAG; } else { tordbg( t, "marking peer %s as a non-seed", tr_peerIoAddrStr( &atom->addr, atom->port ) ); atom->flags &= ~ADDED_F_SEED_FLAG; } } break; } case TR_PEER_CLIENT_GOT_BLOCK: { tr_torrent * tor = t->tor; tr_block_index_t block = _tr_block( tor, e->pieceIndex, e->offset ); tr_cpBlockAdd( &tor->completion, block ); decrementPieceRequests( t, e->pieceIndex ); broadcastGotBlock( t, e->pieceIndex, e->offset, e->length ); if( tr_cpPieceIsComplete( &tor->completion, e->pieceIndex ) ) { const tr_piece_index_t p = e->pieceIndex; const tr_bool ok = tr_ioTestPiece( tor, p, NULL, 0 ); if( !ok ) { tr_torerr( tor, _( "Piece %lu, which was just downloaded, failed its checksum test" ), (unsigned long)p ); } tr_torrentSetHasPiece( tor, p, ok ); tr_torrentSetPieceChecked( tor, p, TRUE ); tr_peerMgrSetBlame( tor, p, ok ); if( !ok ) { gotBadPiece( t, p ); } else { int i; int peerCount; tr_peer ** peers; tr_file_index_t fileIndex; peerCount = tr_ptrArraySize( &t->peers ); peers = (tr_peer**) tr_ptrArrayBase( &t->peers ); for( i=0; imsgs, p ); for( fileIndex=0; fileIndexinfo.fileCount; ++fileIndex ) { const tr_file * file = &tor->info.files[fileIndex]; if( ( file->firstPiece <= p ) && ( p <= file->lastPiece ) && tr_cpFileIsComplete( &tor->completion, fileIndex ) ) { char * path = tr_buildPath( tor->downloadDir, file->name, NULL ); tordbg( t, "closing recently-completed file \"%s\"", path ); tr_fdFileClose( path ); tr_free( path ); } } } tr_torrentRecheckCompleteness( tor ); } break; } case TR_PEER_ERROR: if( e->err == EINVAL ) { addStrike( t, peer ); peer->doPurge = 1; tordbg( t, "setting %s doPurge flag because we got an EINVAL error", tr_peerIoAddrStr( &peer->addr, peer->port ) ); } else if( ( e->err == ERANGE ) || ( e->err == EMSGSIZE ) || ( e->err == ENOTCONN ) ) { /* some protocol error from the peer */ peer->doPurge = 1; tordbg( t, "setting %s doPurge flag because we got an ERANGE, EMSGSIZE, or ENOTCONN error", tr_peerIoAddrStr( &peer->addr, peer->port ) ); } else /* a local error, such as an IO error */ { t->tor->error = e->err; tr_strlcpy( t->tor->errorString, tr_strerror( t->tor->error ), sizeof( t->tor->errorString ) ); tr_torrentStop( t->tor ); } break; default: assert( 0 ); } torrentUnlock( t ); } static void ensureAtomExists( Torrent * t, const tr_address * addr, tr_port port, uint8_t flags, uint8_t from ) { if( getExistingAtom( t, addr ) == NULL ) { struct peer_atom * a; a = tr_new0( struct peer_atom, 1 ); a->addr = *addr; a->port = port; a->flags = flags; a->from = from; tordbg( t, "got a new atom: %s", tr_peerIoAddrStr( &a->addr, a->port ) ); tr_ptrArrayInsertSorted( &t->pool, a, comparePeerAtoms ); } } static int getMaxPeerCount( const tr_torrent * tor ) { return tor->maxConnectedPeers; } static int getPeerCount( const Torrent * t ) { return tr_ptrArraySize( &t->peers );/* + tr_ptrArraySize( &t->outgoingHandshakes ); */ } /* FIXME: this is kind of a mess. */ static tr_bool myHandshakeDoneCB( tr_handshake * handshake, tr_peerIo * io, tr_bool isConnected, const uint8_t * peer_id, void * vmanager ) { tr_bool ok = isConnected; tr_bool success = FALSE; tr_port port; const tr_address * addr; tr_peerMgr * manager = vmanager; Torrent * t; tr_handshake * ours; assert( io ); assert( tr_isBool( ok ) ); t = tr_peerIoHasTorrentHash( io ) ? getExistingTorrent( manager, tr_peerIoGetTorrentHash( io ) ) : NULL; if( tr_peerIoIsIncoming ( io ) ) ours = tr_ptrArrayRemoveSorted( &manager->incomingHandshakes, handshake, handshakeCompare ); else if( t ) ours = tr_ptrArrayRemoveSorted( &t->outgoingHandshakes, handshake, handshakeCompare ); else ours = handshake; assert( ours ); assert( ours == handshake ); if( t ) torrentLock( t ); addr = tr_peerIoGetAddress( io, &port ); if( !ok || !t || !t->isRunning ) { if( t ) { struct peer_atom * atom = getExistingAtom( t, addr ); if( atom ) ++atom->numFails; } } else /* looking good */ { struct peer_atom * atom; ensureAtomExists( t, addr, port, 0, TR_PEER_FROM_INCOMING ); atom = getExistingAtom( t, addr ); atom->time = time( NULL ); atom->piece_data_time = 0; if( atom->myflags & MYFLAG_BANNED ) { tordbg( t, "banned peer %s tried to reconnect", tr_peerIoAddrStr( &atom->addr, atom->port ) ); } else if( tr_peerIoIsIncoming( io ) && ( getPeerCount( t ) >= getMaxPeerCount( t->tor ) ) ) { } else { tr_peer * peer = getExistingPeer( t, addr ); if( peer ) /* we already have this peer */ { } else { peer = getPeer( t, addr ); tr_free( peer->client ); if( !peer_id ) peer->client = NULL; else { char client[128]; tr_clientForId( client, sizeof( client ), peer_id ); peer->client = tr_strdup( client ); } peer->port = port; peer->atom = atom; peer->io = tr_handshakeStealIO( handshake ); /* this steals its refcount too, which is balanced by our unref in peerDestructor() */ tr_peerIoSetParent( peer->io, t->tor->bandwidth ); tr_peerMsgsNew( t->tor, peer, peerCallbackFunc, t, &peer->msgsTag ); success = TRUE; } } } if( t ) torrentUnlock( t ); return success; } void tr_peerMgrAddIncoming( tr_peerMgr * manager, tr_address * addr, tr_port port, int socket ) { managerLock( manager ); if( tr_sessionIsAddressBlocked( manager->session, addr ) ) { tr_dbg( "Banned IP address \"%s\" tried to connect to us", tr_ntop_non_ts( addr ) ); tr_netClose( socket ); } else if( getExistingHandshake( &manager->incomingHandshakes, addr ) ) { tr_netClose( socket ); } else /* we don't have a connetion to them yet... */ { tr_peerIo * io; tr_handshake * handshake; io = tr_peerIoNewIncoming( manager->session, manager->session->bandwidth, addr, port, socket ); handshake = tr_handshakeNew( io, manager->session->encryptionMode, myHandshakeDoneCB, manager ); tr_peerIoUnref( io ); /* balanced by the implicit ref in tr_peerIoNewIncoming() */ tr_ptrArrayInsertSorted( &manager->incomingHandshakes, handshake, handshakeCompare ); } managerUnlock( manager ); } static tr_bool tr_isPex( const tr_pex * pex ) { return pex && tr_isAddress( &pex->addr ); } void tr_peerMgrAddPex( tr_torrent * tor, uint8_t from, const tr_pex * pex ) { if( tr_isPex( pex ) ) /* safeguard against corrupt data */ { Torrent * t = tor->torrentPeers; managerLock( t->manager ); if( !tr_sessionIsAddressBlocked( t->manager->session, &pex->addr ) ) if( tr_isValidPeerAddress( &pex->addr, pex->port ) ) ensureAtomExists( t, &pex->addr, pex->port, pex->flags, from ); managerUnlock( t->manager ); } } tr_pex * tr_peerMgrCompactToPex( const void * compact, size_t compactLen, const uint8_t * added_f, size_t added_f_len, size_t * pexCount ) { size_t i; size_t n = compactLen / 6; const uint8_t * walk = compact; tr_pex * pex = tr_new0( tr_pex, n ); for( i = 0; i < n; ++i ) { pex[i].addr.type = TR_AF_INET; memcpy( &pex[i].addr.addr, walk, 4 ); walk += 4; memcpy( &pex[i].port, walk, 2 ); walk += 2; if( added_f && ( n == added_f_len ) ) pex[i].flags = added_f[i]; } *pexCount = n; return pex; } tr_pex * tr_peerMgrCompact6ToPex( const void * compact, size_t compactLen, const uint8_t * added_f, size_t added_f_len, size_t * pexCount ) { size_t i; size_t n = compactLen / 18; const uint8_t * walk = compact; tr_pex * pex = tr_new0( tr_pex, n ); for( i = 0; i < n; ++i ) { pex[i].addr.type = TR_AF_INET6; memcpy( &pex[i].addr.addr.addr6.s6_addr, walk, 16 ); walk += 16; memcpy( &pex[i].port, walk, 2 ); walk += 2; if( added_f && ( n == added_f_len ) ) pex[i].flags = added_f[i]; } *pexCount = n; return pex; } tr_pex * tr_peerMgrArrayToPex( const void * array, size_t arrayLen, size_t * pexCount ) { size_t i; size_t n = arrayLen / ( sizeof( tr_address ) + 2 ); /*size_t n = arrayLen / sizeof( tr_peerArrayElement );*/ const uint8_t * walk = array; tr_pex * pex = tr_new0( tr_pex, n ); for( i = 0 ; i < n ; i++ ) { memcpy( &pex[i].addr, walk, sizeof( tr_address ) ); memcpy( &pex[i].port, walk + sizeof( tr_address ), 2 ); pex[i].flags = 0x00; walk += sizeof( tr_address ) + 2; } *pexCount = n; return pex; } /** *** **/ void tr_peerMgrSetBlame( tr_torrent * tor, tr_piece_index_t pieceIndex, int success ) { if( !success ) { int peerCount, i; Torrent * t = tor->torrentPeers; tr_peer ** peers; assert( torrentIsLocked( t ) ); peers = (tr_peer **) tr_ptrArrayPeek( &t->peers, &peerCount ); for( i = 0; i < peerCount; ++i ) { tr_peer * peer = peers[i]; if( tr_bitfieldHas( peer->blame, pieceIndex ) ) { tordbg( t, "peer %s contributed to corrupt piece (%d); now has %d strikes", tr_peerIoAddrStr( &peer->addr, peer->port ), pieceIndex, (int)peer->strikes + 1 ); addStrike( t, peer ); } } } } int tr_pexCompare( const void * va, const void * vb ) { const tr_pex * a = va; const tr_pex * b = vb; int i; assert( tr_isPex( a ) ); assert( tr_isPex( b ) ); if(( i = tr_compareAddresses( &a->addr, &b->addr ))) return i; if( a->port != b->port ) return a->port < b->port ? -1 : 1; return 0; } static int peerPrefersCrypto( const tr_peer * peer ) { if( peer->encryption_preference == ENCRYPTION_PREFERENCE_YES ) return TRUE; if( peer->encryption_preference == ENCRYPTION_PREFERENCE_NO ) return FALSE; return tr_peerIoIsEncrypted( peer->io ); } int tr_peerMgrGetPeers( tr_torrent * tor, tr_pex ** setme_pex, uint8_t af) { int peersReturning = 0; const Torrent * t = tor->torrentPeers; managerLock( t->manager ); { int i; const tr_peer ** peers = (const tr_peer**) tr_ptrArrayBase( &t->peers ); const int peerCount = tr_ptrArraySize( &t->peers ); /* for now, this will waste memory on torrents that have both * ipv6 and ipv4 peers */ tr_pex * pex = tr_new( tr_pex, peerCount ); tr_pex * walk = pex; for( i=0; iaddr.type == af ) { const struct peer_atom * atom = peer->atom; assert( tr_isAddress( &peer->addr ) ); walk->addr = peer->addr; walk->port = peer->port; walk->flags = 0; if( peerPrefersCrypto( peer ) ) walk->flags |= ADDED_F_ENCRYPTION_FLAG; if( ( atom->uploadOnly == UPLOAD_ONLY_YES ) || ( peer->progress >= 1.0 ) ) walk->flags |= ADDED_F_SEED_FLAG; ++peersReturning; ++walk; } } assert( ( walk - pex ) == peersReturning ); qsort( pex, peersReturning, sizeof( tr_pex ), tr_pexCompare ); *setme_pex = pex; } managerUnlock( t->manager ); return peersReturning; } void tr_peerMgrStartTorrent( tr_torrent * tor ) { Torrent * t = tor->torrentPeers; managerLock( t->manager ); assert( t ); if( !t->isRunning ) { t->isRunning = TRUE; if( !tr_ptrArrayEmpty( &t->webseeds ) ) refillSoon( t ); } managerUnlock( t->manager ); } static void stopTorrent( Torrent * t ) { assert( torrentIsLocked( t ) ); t->isRunning = FALSE; /* disconnect the peers. */ tr_ptrArrayForeach( &t->peers, (PtrArrayForeachFunc)peerDestructor ); tr_ptrArrayClear( &t->peers ); /* disconnect the handshakes. handshakeAbort calls handshakeDoneCB(), * which removes the handshake from t->outgoingHandshakes... */ while( !tr_ptrArrayEmpty( &t->outgoingHandshakes ) ) tr_handshakeAbort( tr_ptrArrayNth( &t->outgoingHandshakes, 0 ) ); } void tr_peerMgrStopTorrent( tr_torrent * tor ) { Torrent * t = tor->torrentPeers; managerLock( t->manager ); stopTorrent( t ); managerUnlock( t->manager ); } void tr_peerMgrAddTorrent( tr_peerMgr * manager, tr_torrent * tor ) { managerLock( manager ); assert( tor ); assert( tor->torrentPeers == NULL ); tor->torrentPeers = torrentConstructor( manager, tor ); managerUnlock( manager ); } void tr_peerMgrRemoveTorrent( tr_torrent * tor ) { tr_torrentLock( tor ); stopTorrent( tor->torrentPeers ); torrentDestructor( tor->torrentPeers ); tr_torrentUnlock( tor ); } void tr_peerMgrTorrentAvailability( const tr_torrent * tor, int8_t * tab, unsigned int tabCount ) { tr_piece_index_t i; const Torrent * t; float interval; tr_bool isSeed; int peerCount; const tr_peer ** peers; tr_torrentLock( tor ); t = tor->torrentPeers; tor = t->tor; interval = tor->info.pieceCount / (float)tabCount; isSeed = tor && ( tr_cpGetStatus ( &tor->completion ) == TR_SEED ); peers = (const tr_peer **) tr_ptrArrayBase( &t->peers ); peerCount = tr_ptrArraySize( &t->peers ); memset( tab, 0, tabCount ); for( i = 0; tor && i < tabCount; ++i ) { const int piece = i * interval; if( isSeed || tr_cpPieceIsComplete( &tor->completion, piece ) ) tab[i] = -1; else if( peerCount ) { int j; for( j = 0; j < peerCount; ++j ) if( tr_bitfieldHas( peers[j]->have, i ) ) ++tab[i]; } } tr_torrentUnlock( tor ); } /* Returns the pieces that are available from peers */ tr_bitfield* tr_peerMgrGetAvailable( const tr_torrent * tor ) { int i; int peerCount; Torrent * t = tor->torrentPeers; const tr_peer ** peers; tr_bitfield * pieces; managerLock( t->manager ); pieces = tr_bitfieldNew( t->tor->info.pieceCount ); peerCount = tr_ptrArraySize( &t->peers ); peers = (const tr_peer**) tr_ptrArrayBase( &t->peers ); for( i=0; ihave ); managerUnlock( t->manager ); return pieces; } void tr_peerMgrTorrentStats( tr_torrent * tor, int * setmePeersKnown, int * setmePeersConnected, int * setmeSeedsConnected, int * setmeWebseedsSendingToUs, int * setmePeersSendingToUs, int * setmePeersGettingFromUs, int * setmePeersFrom ) { int i, size; const Torrent * t = tor->torrentPeers; const tr_peer ** peers; const tr_webseed ** webseeds; managerLock( t->manager ); peers = (const tr_peer **) tr_ptrArrayBase( &t->peers ); size = tr_ptrArraySize( &t->peers ); *setmePeersKnown = tr_ptrArraySize( &t->pool ); *setmePeersConnected = 0; *setmeSeedsConnected = 0; *setmePeersGettingFromUs = 0; *setmePeersSendingToUs = 0; *setmeWebseedsSendingToUs = 0; for( i=0; iatom; if( peer->io == NULL ) /* not connected */ continue; ++*setmePeersConnected; ++setmePeersFrom[atom->from]; if( clientIsDownloadingFrom( peer ) ) ++*setmePeersSendingToUs; if( clientIsUploadingTo( peer ) ) ++*setmePeersGettingFromUs; if( atom->flags & ADDED_F_SEED_FLAG ) ++*setmeSeedsConnected; } webseeds = (const tr_webseed**) tr_ptrArrayBase( &t->webseeds ); size = tr_ptrArraySize( &t->webseeds ); for( i=0; imanager ); } float* tr_peerMgrWebSpeeds( const tr_torrent * tor ) { const Torrent * t = tor->torrentPeers; const tr_webseed ** webseeds; int i; int webseedCount; float * ret; uint64_t now; assert( t->manager ); managerLock( t->manager ); webseeds = (const tr_webseed**) tr_ptrArrayBase( &t->webseeds ); webseedCount = tr_ptrArraySize( &t->webseeds ); assert( webseedCount == tor->info.webseedCount ); ret = tr_new0( float, webseedCount ); now = tr_date( ); for( i=0; imanager ); return ret; } double tr_peerGetPieceSpeed( const tr_peer * peer, uint64_t now, tr_direction direction ) { return peer->io ? tr_peerIoGetPieceSpeed( peer->io, now, direction ) : 0.0; } struct tr_peer_stat * tr_peerMgrPeerStats( const tr_torrent * tor, int * setmeCount ) { int i, size; const Torrent * t = tor->torrentPeers; const tr_peer ** peers; tr_peer_stat * ret; uint64_t now; assert( t->manager ); managerLock( t->manager ); size = tr_ptrArraySize( &t->peers ); peers = (const tr_peer**) tr_ptrArrayBase( &t->peers ); ret = tr_new0( tr_peer_stat, size ); now = tr_date( ); for( i=0; iatom; tr_peer_stat * stat = ret + i; tr_ntop( &peer->addr, stat->addr, sizeof( stat->addr ) ); tr_strlcpy( stat->client, ( peer->client ? peer->client : "" ), sizeof( stat->client ) ); stat->port = ntohs( peer->port ); stat->from = atom->from; stat->progress = peer->progress; stat->isEncrypted = tr_peerIoIsEncrypted( peer->io ) ? 1 : 0; stat->rateToPeer = tr_peerGetPieceSpeed( peer, now, TR_CLIENT_TO_PEER ); stat->rateToClient = tr_peerGetPieceSpeed( peer, now, TR_PEER_TO_CLIENT ); stat->peerIsChoked = peer->peerIsChoked; stat->peerIsInterested = peer->peerIsInterested; stat->clientIsChoked = peer->clientIsChoked; stat->clientIsInterested = peer->clientIsInterested; stat->isIncoming = tr_peerIoIsIncoming( peer->io ); stat->isDownloadingFrom = clientIsDownloadingFrom( peer ); stat->isUploadingTo = clientIsUploadingTo( peer ); stat->isSeed = ( atom->uploadOnly == UPLOAD_ONLY_YES ) || ( peer->progress >= 1.0 ); pch = stat->flagStr; if( t->optimistic == peer ) *pch++ = 'O'; if( stat->isDownloadingFrom ) *pch++ = 'D'; else if( stat->clientIsInterested ) *pch++ = 'd'; if( stat->isUploadingTo ) *pch++ = 'U'; else if( stat->peerIsInterested ) *pch++ = 'u'; if( !stat->clientIsChoked && !stat->clientIsInterested ) *pch++ = 'K'; if( !stat->peerIsChoked && !stat->peerIsInterested ) *pch++ = '?'; if( stat->isEncrypted ) *pch++ = 'E'; if( stat->from == TR_PEER_FROM_PEX ) *pch++ = 'X'; if( stat->isIncoming ) *pch++ = 'I'; *pch = '\0'; } *setmeCount = size; managerUnlock( t->manager ); return ret; } /** *** **/ struct ChokeData { tr_bool doUnchoke; tr_bool isInterested; tr_bool isChoked; int rate; tr_peer * peer; }; static int compareChoke( const void * va, const void * vb ) { const struct ChokeData * a = va; const struct ChokeData * b = vb; if( a->rate != b->rate ) /* prefer higher overall speeds */ return a->rate > b->rate ? -1 : 1; if( a->isChoked != b->isChoked ) /* prefer unchoked */ return a->isChoked ? 1 : -1; return 0; } static int isNew( const tr_peer * peer ) { return peer && peer->io && tr_peerIoGetAge( peer->io ) < 45; } static int isSame( const tr_peer * peer ) { return peer && peer->client && strstr( peer->client, "Transmission" ); } /** *** **/ static void rechokeTorrent( Torrent * t ) { int i, size, unchokedInterested; const int peerCount = tr_ptrArraySize( &t->peers ); tr_peer ** peers = (tr_peer**) tr_ptrArrayBase( &t->peers ); struct ChokeData * choke = tr_new0( struct ChokeData, peerCount ); const tr_session * session = t->manager->session; const int chokeAll = !tr_torrentIsPieceTransferAllowed( t->tor, TR_CLIENT_TO_PEER ); const uint64_t now = tr_date( ); assert( torrentIsLocked( t ) ); /* sort the peers by preference and rate */ for( i = 0, size = 0; i < peerCount; ++i ) { tr_peer * peer = peers[i]; struct peer_atom * atom = peer->atom; if( peer->progress >= 1.0 ) /* choke all seeds */ { tr_peerMsgsSetChoke( peer->msgs, TRUE ); } else if( atom->uploadOnly == UPLOAD_ONLY_YES ) /* choke partial seeds */ { tr_peerMsgsSetChoke( peer->msgs, TRUE ); } else if( chokeAll ) /* choke everyone if we're not uploading */ { tr_peerMsgsSetChoke( peer->msgs, TRUE ); } else { struct ChokeData * n = &choke[size++]; n->peer = peer; n->isInterested = peer->peerIsInterested; n->isChoked = peer->peerIsChoked; n->rate = tr_peerGetPieceSpeed( peer, now, TR_CLIENT_TO_PEER ) * 1024; } } qsort( choke, size, sizeof( struct ChokeData ), compareChoke ); /** * Reciprocation and number of uploads capping is managed by unchoking * the N peers which have the best upload rate and are interested. * This maximizes the client's download rate. These N peers are * referred to as downloaders, because they are interested in downloading * from the client. * * Peers which have a better upload rate (as compared to the downloaders) * but aren't interested get unchoked. If they become interested, the * downloader with the worst upload rate gets choked. If a client has * a complete file, it uses its upload rate rather than its download * rate to decide which peers to unchoke. */ unchokedInterested = 0; for( i=0; iuploadSlotsPerTorrent; ++i ) { choke[i].doUnchoke = 1; if( choke[i].isInterested ) ++unchokedInterested; } /* optimistic unchoke */ if( i < size ) { int n; struct ChokeData * c; tr_ptrArray randPool = TR_PTR_ARRAY_INIT; for( ; idoUnchoke = 1; t->optimistic = c->peer; } tr_ptrArrayDestruct( &randPool, NULL ); } for( i=0; imsgs, !choke[i].doUnchoke ); /* cleanup */ tr_free( choke ); } static int rechokePulse( void * vmgr ) { tr_torrent * tor = NULL; tr_peerMgr * mgr = vmgr; managerLock( mgr ); while(( tor = tr_torrentNext( mgr->session, tor ))) if( tor->isRunning ) rechokeTorrent( tor->torrentPeers ); managerUnlock( mgr ); return TRUE; } /*** **** **** Life and Death **** ***/ typedef enum { TR_CAN_KEEP, TR_CAN_CLOSE, TR_MUST_CLOSE, } tr_close_type_t; static tr_close_type_t shouldPeerBeClosed( const Torrent * t, const tr_peer * peer, int peerCount ) { const tr_torrent * tor = t->tor; const time_t now = time( NULL ); const struct peer_atom * atom = peer->atom; /* if it's marked for purging, close it */ if( peer->doPurge ) { tordbg( t, "purging peer %s because its doPurge flag is set", tr_peerIoAddrStr( &atom->addr, atom->port ) ); return TR_MUST_CLOSE; } /* if we're seeding and the peer has everything we have, * and enough time has passed for a pex exchange, then disconnect */ if( tr_torrentIsSeed( tor ) ) { int peerHasEverything; if( atom->flags & ADDED_F_SEED_FLAG ) peerHasEverything = TRUE; else if( peer->progress < tr_cpPercentDone( &tor->completion ) ) peerHasEverything = FALSE; else { tr_bitfield * tmp = tr_bitfieldDup( tr_cpPieceBitfield( &tor->completion ) ); tr_bitfieldDifference( tmp, peer->have ); peerHasEverything = tr_bitfieldCountTrueBits( tmp ) == 0; tr_bitfieldFree( tmp ); } if( peerHasEverything && ( !tr_torrentAllowsPex(tor) || (now-atom->time>=30 ))) { tordbg( t, "purging peer %s because we're both seeds", tr_peerIoAddrStr( &atom->addr, atom->port ) ); return TR_MUST_CLOSE; } } /* disconnect if it's been too long since piece data has been transferred. * this is on a sliding scale based on number of available peers... */ { const int relaxStrictnessIfFewerThanN = (int)( ( getMaxPeerCount( tor ) * 0.9 ) + 0.5 ); /* if we have >= relaxIfFewerThan, strictness is 100%. * if we have zero connections, strictness is 0% */ const float strictness = peerCount >= relaxStrictnessIfFewerThanN ? 1.0 : peerCount / (float)relaxStrictnessIfFewerThanN; const int lo = MIN_UPLOAD_IDLE_SECS; const int hi = MAX_UPLOAD_IDLE_SECS; const int limit = hi - ( ( hi - lo ) * strictness ); const int idleTime = now - MAX( atom->time, atom->piece_data_time ); /*fprintf( stderr, "strictness is %.3f, limit is %d seconds... time since connect is %d, time since piece is %d ... idleTime is %d, doPurge is %d\n", (double)strictness, limit, (int)(now - atom->time), (int)(now - atom->piece_data_time), idleTime, idleTime > limit );*/ if( idleTime > limit ) { tordbg( t, "purging peer %s because it's been %d secs since we shared anything", tr_peerIoAddrStr( &atom->addr, atom->port ), idleTime ); return TR_CAN_CLOSE; } } return TR_CAN_KEEP; } static tr_peer ** getPeersToClose( Torrent * t, tr_close_type_t closeType, int * setmeSize ) { int i, peerCount, outsize; tr_peer ** peers = (tr_peer**) tr_ptrArrayPeek( &t->peers, &peerCount ); struct tr_peer ** ret = tr_new( tr_peer *, peerCount ); assert( torrentIsLocked( t ) ); for( i = outsize = 0; i < peerCount; ++i ) if( shouldPeerBeClosed( t, peers[i], peerCount ) == closeType ) ret[outsize++] = peers[i]; *setmeSize = outsize; return ret; } static int compareCandidates( const void * va, const void * vb ) { const struct peer_atom * a = *(const struct peer_atom**) va; const struct peer_atom * b = *(const struct peer_atom**) vb; /* Here we would probably want to try reconnecting to * peers that had most recently given us data. Lots of users have * trouble with resets due to their routers and/or ISPs. This way we * can quickly recover from an unwanted reset. So we sort * piece_data_time in descending order. */ if( a->piece_data_time != b->piece_data_time ) return a->piece_data_time < b->piece_data_time ? 1 : -1; if( a->numFails != b->numFails ) return a->numFails < b->numFails ? -1 : 1; if( a->time != b->time ) return a->time < b->time ? -1 : 1; /* all other things being equal, prefer peers whose * information comes from a more reliable source */ if( a->from != b->from ) return a->from < b->from ? -1 : 1; return 0; } static int getReconnectIntervalSecs( const struct peer_atom * atom ) { int sec; const time_t now = time( NULL ); /* if we were recently connected to this peer and transferring piece * data, try to reconnect to them sooner rather that later -- we don't * want network troubles to get in the way of a good peer. */ if( ( now - atom->piece_data_time ) <= ( MINIMUM_RECONNECT_INTERVAL_SECS * 2 ) ) sec = MINIMUM_RECONNECT_INTERVAL_SECS; /* don't allow reconnects more often than our minimum */ else if( ( now - atom->time ) < MINIMUM_RECONNECT_INTERVAL_SECS ) sec = MINIMUM_RECONNECT_INTERVAL_SECS; /* otherwise, the interval depends on how many times we've tried * and failed to connect to the peer */ else switch( atom->numFails ) { case 0: sec = 0; break; case 1: sec = 5; break; case 2: sec = 2 * 60; break; case 3: sec = 15 * 60; break; case 4: sec = 30 * 60; break; case 5: sec = 60 * 60; break; default: sec = 120 * 60; break; } return sec; } static struct peer_atom ** getPeerCandidates( Torrent * t, int * setmeSize ) { int i, atomCount, retCount; struct peer_atom ** atoms; struct peer_atom ** ret; const time_t now = time( NULL ); const int seed = tr_torrentIsSeed( t->tor ); assert( torrentIsLocked( t ) ); atoms = (struct peer_atom**) tr_ptrArrayPeek( &t->pool, &atomCount ); ret = tr_new( struct peer_atom*, atomCount ); for( i = retCount = 0; i < atomCount; ++i ) { int interval; struct peer_atom * atom = atoms[i]; /* peer fed us too much bad data ... we only keep it around * now to weed it out in case someone sends it to us via pex */ if( atom->myflags & MYFLAG_BANNED ) continue; /* peer was unconnectable before, so we're not going to keep trying. * this is needs a separate flag from `banned', since if they try * to connect to us later, we'll let them in */ if( atom->myflags & MYFLAG_UNREACHABLE ) continue; /* we don't need two connections to the same peer... */ if( peerIsInUse( t, &atom->addr ) ) continue; /* no need to connect if we're both seeds... */ if( seed && ( ( atom->flags & ADDED_F_SEED_FLAG ) || ( atom->uploadOnly == UPLOAD_ONLY_YES ) ) ) continue; /* don't reconnect too often */ interval = getReconnectIntervalSecs( atom ); if( ( now - atom->time ) < interval ) { tordbg( t, "RECONNECT peer %d (%s) is in its grace period of %d seconds..", i, tr_peerIoAddrStr( &atom->addr, atom->port ), interval ); continue; } /* Don't connect to peers in our blocklist */ if( tr_sessionIsAddressBlocked( t->manager->session, &atom->addr ) ) continue; ret[retCount++] = atom; } qsort( ret, retCount, sizeof( struct peer_atom* ), compareCandidates ); *setmeSize = retCount; return ret; } static void closePeer( Torrent * t, tr_peer * peer ) { struct peer_atom * atom; assert( t != NULL ); assert( peer != NULL ); atom = peer->atom; /* if we transferred piece data, then they might be good peers, so reset their `numFails' weight to zero. otherwise we connected to them fruitlessly, so mark it as another fail */ if( atom->piece_data_time ) atom->numFails = 0; else ++atom->numFails; tordbg( t, "removing bad peer %s", tr_peerIoGetAddrStr( peer->io ) ); removePeer( t, peer ); } static void reconnectTorrent( Torrent * t ) { static time_t prevTime = 0; static int newConnectionsThisSecond = 0; time_t now; now = time( NULL ); if( prevTime != now ) { prevTime = now; newConnectionsThisSecond = 0; } if( !t->isRunning ) { removeAllPeers( t ); } else { int i; int canCloseCount; int mustCloseCount; int candidateCount; int maxCandidates; struct tr_peer ** canClose = getPeersToClose( t, TR_CAN_CLOSE, &canCloseCount ); struct tr_peer ** mustClose = getPeersToClose( t, TR_MUST_CLOSE, &mustCloseCount ); struct peer_atom ** candidates = getPeerCandidates( t, &candidateCount ); tordbg( t, "reconnect pulse for [%s]: " "%d must-close connections, " "%d can-close connections, " "%d connection candidates, " "%d atoms, " "max per pulse is %d", t->tor->info.name, mustCloseCount, canCloseCount, candidateCount, tr_ptrArraySize( &t->pool ), MAX_RECONNECTIONS_PER_PULSE ); /* disconnect the really bad peers */ for( i=0; itor ) - getPeerCount( t ) ); maxCandidates = MIN( maxCandidates, MAX_CONNECTIONS_PER_SECOND - newConnectionsThisSecond ); /* maybe disconnect some lesser peers, if we have candidates to replace them with */ for( i=0; ( itor ), newConnectionsThisSecond, MAX_CONNECTIONS_PER_SECOND ); /* add some new ones */ for( i=0; imanager; struct peer_atom * atom = candidates[i]; tr_peerIo * io; tordbg( t, "Starting an OUTGOING connection with %s", tr_peerIoAddrStr( &atom->addr, atom->port ) ); io = tr_peerIoNewOutgoing( mgr->session, mgr->session->bandwidth, &atom->addr, atom->port, t->hash ); if( io == NULL ) { tordbg( t, "peerIo not created; marking peer %s as unreachable", tr_peerIoAddrStr( &atom->addr, atom->port ) ); atom->myflags |= MYFLAG_UNREACHABLE; } else { tr_handshake * handshake = tr_handshakeNew( io, mgr->session->encryptionMode, myHandshakeDoneCB, mgr ); assert( tr_peerIoGetTorrentHash( io ) ); tr_peerIoUnref( io ); /* balanced by the implicit ref in tr_peerIoNewOutgoing() */ ++newConnectionsThisSecond; tr_ptrArrayInsertSorted( &t->outgoingHandshakes, handshake, handshakeCompare ); } atom->time = time( NULL ); } /* cleanup */ tr_free( candidates ); tr_free( mustClose ); tr_free( canClose ); } } static int reconnectPulse( void * vmgr ) { tr_torrent * tor = NULL; tr_peerMgr * mgr = vmgr; managerLock( mgr ); while(( tor = tr_torrentNext( mgr->session, tor ))) if( tor->isRunning ) reconnectTorrent( tor->torrentPeers ); managerUnlock( mgr ); return TRUE; } /**** ***** ***** BANDWIDTH ALLOCATION ***** ****/ static void pumpAllPeers( tr_peerMgr * mgr ) { tr_torrent * tor = NULL; while(( tor = tr_torrentNext( mgr->session, tor ))) { int j; Torrent * t = tor->torrentPeers; for( j=0; jpeers ); ++j ) { tr_peer * peer = tr_ptrArrayNth( &t->peers, j ); tr_peerMsgsPulse( peer->msgs ); } } } static int bandwidthPulse( void * vmgr ) { tr_torrent * tor = NULL; tr_peerMgr * mgr = vmgr; managerLock( mgr ); /* FIXME: this next line probably isn't necessary... */ pumpAllPeers( mgr ); /* allocate bandwidth to the peers */ tr_bandwidthAllocate( mgr->session->bandwidth, TR_UP, BANDWIDTH_PERIOD_MSEC ); tr_bandwidthAllocate( mgr->session->bandwidth, TR_DOWN, BANDWIDTH_PERIOD_MSEC ); /* possibly stop torrents that have seeded enough */ while(( tor = tr_torrentNext( mgr->session, tor ))) { if( tor->needsSeedRatioCheck ) { tor->needsSeedRatioCheck = FALSE; tr_torrentCheckSeedRatio( tor ); } } managerUnlock( mgr ); return TRUE; }