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transmission/libtransmission/peer-mgr.c

2579 lines
73 KiB
C

/*
* This file Copyright (C) 2007-2008 Charles Kerr <charles@rebelbase.com>
*
* 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 <assert.h>
#include <errno.h>
#include <string.h> /* memcpy, memcmp, strstr */
#include <stdlib.h> /* qsort */
#include <limits.h> /* INT_MAX */
#include <event.h>
#include "transmission.h"
#include "blocklist.h"
#include "clients.h"
#include "completion.h"
#include "crypto.h"
#include "handshake.h"
#include "inout.h" /* tr_ioTestPiece */
#include "net.h"
#include "peer-io.h"
#include "peer-mgr.h"
#include "peer-mgr-private.h"
#include "peer-msgs.h"
#include "ptrarray.h"
#include "stats.h" /* 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 = 333,
/* when many peers are available, keep idle ones this long */
MIN_UPLOAD_IDLE_SECS = ( 60 * 3 ),
/* when few peers are available, keep idle ones this long */
MAX_UPLOAD_IDLE_SECS = ( 60 * 10 ),
/* how frequently to decide which peers live and die */
RECONNECT_PERIOD_MSEC = ( 2 * 1000 ),
/* max # of peers to ask fer per torrent per reconnect pulse */
MAX_RECONNECTIONS_PER_PULSE = 2,
/* max number of peers to ask for per second overall.
* this throttle is to avoid overloading the router */
MAX_CONNECTIONS_PER_SECOND = 4,
/* number of unchoked peers per torrent.
* FIXME: this probably ought to be configurable */
MAX_UNCHOKED_PEERS = 12,
/* number of bad pieces a peer is allowed to send before we ban them */
MAX_BAD_PIECES_PER_PEER = 3,
/* use for bitwise operations w/peer_atom.myflags */
MYFLAG_BANNED = 1,
/* 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
};
/**
***
**/
/* We keep one of these for every peer we know about, whether
* it's connected or not, so the struct must be small.
* When our current connections underperform, we dip back
* into this list for new ones. */
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 */
uint16_t port;
uint16_t numFails;
struct in_addr addr;
time_t time; /* when the peer's connection status last changed */
time_t piece_data_time;
};
typedef struct
{
unsigned int isRunning : 1;
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 * reconnectTimer;
tr_timer * rechokeTimer;
tr_timer * refillTimer;
tr_torrent * tor;
tr_peer * optimistic; /* the optimistic peer, or NULL if none */
struct tr_peerMgr * manager;
}
Torrent;
struct tr_peerMgr
{
uint8_t bandwidthPulseNumber;
tr_session * session;
tr_ptrArray * torrents; /* Torrent */
tr_ptrArray * incomingHandshakes; /* tr_handshake */
tr_timer * bandwidthTimer;
double rateHistory[2][BANDWIDTH_PULSE_HISTORY];
double globalPoolHistory[2][BANDWIDTH_PULSE_HISTORY];
};
#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 void
managerLock( const struct tr_peerMgr * manager )
{
tr_globalLock( manager->session );
}
static void
managerUnlock( const struct tr_peerMgr * manager )
{
tr_globalUnlock( manager->session );
}
static void
torrentLock( Torrent * torrent )
{
managerLock( torrent->manager );
}
static void
torrentUnlock( Torrent * torrent )
{
managerUnlock( torrent->manager );
}
static int
torrentIsLocked( const Torrent * t )
{
return tr_globalIsLocked( t->manager->session );
}
/**
***
**/
static int
compareAddresses( const struct in_addr * a,
const struct in_addr * b )
{
if( a->s_addr != b->s_addr )
return a->s_addr < b->s_addr ? -1 : 1;
return 0;
}
static int
handshakeCompareToAddr( const void * va,
const void * vb )
{
const tr_handshake * a = va;
return 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 struct in_addr * in_addr )
{
return tr_ptrArrayFindSorted( handshakes,
in_addr,
handshakeCompareToAddr );
}
static int
comparePeerAtomToAddress( const void * va,
const void * vb )
{
const struct peer_atom * a = va;
return 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 int
torrentCompare( const void * va,
const void * vb )
{
const Torrent * a = va;
const Torrent * b = vb;
return memcmp( a->hash, b->hash, SHA_DIGEST_LENGTH );
}
static int
torrentCompareToHash( const void * va,
const void * vb )
{
const Torrent * a = va;
const uint8_t * b_hash = vb;
return memcmp( a->hash, b_hash, SHA_DIGEST_LENGTH );
}
static Torrent*
getExistingTorrent( tr_peerMgr * manager,
const uint8_t * hash )
{
return (Torrent*) tr_ptrArrayFindSorted( manager->torrents,
hash,
torrentCompareToHash );
}
static int
peerCompare( const void * va,
const void * vb )
{
const tr_peer * a = va;
const tr_peer * b = vb;
return compareAddresses( &a->in_addr, &b->in_addr );
}
static int
peerCompareToAddr( const void * va,
const void * vb )
{
const tr_peer * a = va;
return compareAddresses( &a->in_addr, vb );
}
static tr_peer*
getExistingPeer( Torrent * torrent,
const struct in_addr * in_addr )
{
assert( torrentIsLocked( torrent ) );
assert( in_addr );
return tr_ptrArrayFindSorted( torrent->peers,
in_addr,
peerCompareToAddr );
}
static struct peer_atom*
getExistingAtom( const Torrent * t,
const struct in_addr * addr )
{
assert( torrentIsLocked( t ) );
return tr_ptrArrayFindSorted( t->pool, addr, comparePeerAtomToAddress );
}
static int
peerIsInUse( const Torrent * ct,
const struct in_addr * 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 struct in_addr * in_addr )
{
tr_peer * p;
p = tr_new0( tr_peer, 1 );
memcpy( &p->in_addr, in_addr, sizeof( struct in_addr ) );
return p;
}
static tr_peer*
getPeer( Torrent * torrent,
const struct in_addr * in_addr )
{
tr_peer * peer;
assert( torrentIsLocked( torrent ) );
peer = getExistingPeer( torrent, in_addr );
if( peer == NULL )
{
peer = peerConstructor( in_addr );
tr_ptrArrayInsertSorted( torrent->peers, peer, peerCompare );
}
return peer;
}
static void
peerDestructor( tr_peer * peer )
{
assert( peer );
assert( peer->msgs );
tr_peerMsgsUnsubscribe( peer->msgs, peer->msgsTag );
tr_peerMsgsFree( peer->msgs );
tr_peerIoFree( peer->io );
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;
assert( torrentIsLocked( t ) );
atom = getExistingAtom( t, &peer->in_addr );
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
torrentDestructor( void * vt )
{
Torrent * t = vt;
uint8_t hash[SHA_DIGEST_LENGTH];
assert( t );
assert( !t->isRunning );
assert( t->peers );
assert( torrentIsLocked( t ) );
assert( tr_ptrArrayEmpty( t->outgoingHandshakes ) );
assert( tr_ptrArrayEmpty( t->peers ) );
memcpy( hash, t->hash, SHA_DIGEST_LENGTH );
tr_timerFree( &t->reconnectTimer );
tr_timerFree( &t->rechokeTimer );
tr_timerFree( &t->refillTimer );
tr_ptrArrayFree( t->webseeds, (PtrArrayForeachFunc)tr_webseedFree );
tr_ptrArrayFree( t->pool, (PtrArrayForeachFunc)tr_free );
tr_ptrArrayFree( t->outgoingHandshakes, NULL );
tr_ptrArrayFree( 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_ptrArrayNew( );
t->peers = tr_ptrArrayNew( );
t->webseeds = tr_ptrArrayNew( );
t->outgoingHandshakes = tr_ptrArrayNew( );
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;
}
/**
* For explanation, see http://www.bittorrent.org/fast_extensions.html
* Also see the "test-allowed-set" unit test
*
* @param k number of pieces in set
* @param sz number of pieces in the torrent
* @param infohash torrent's SHA1 hash
* @param ip peer's address
*/
struct tr_bitfield *
tr_peerMgrGenerateAllowedSet(
const uint32_t k,
const uint32_t sz,
const uint8_t *
infohash,
const struct in_addr * ip )
{
uint8_t w[SHA_DIGEST_LENGTH + 4];
uint8_t x[SHA_DIGEST_LENGTH];
tr_bitfield * a;
uint32_t a_size;
*(uint32_t*)w = ntohl( htonl( ip->s_addr ) & 0xffffff00 ); /* (1) */
memcpy( w + 4, infohash, SHA_DIGEST_LENGTH ); /* (2) */
tr_sha1( x, w, sizeof( w ), NULL ); /* (3) */
a = tr_bitfieldNew( sz );
a_size = 0;
while( a_size < k )
{
int i;
for( i = 0; i < 5 && a_size < k; ++i ) /* (4) */
{
uint32_t j = i * 4; /* (5) */
uint32_t y = ntohl( *( uint32_t* )( x + j ) ); /* (6) */
uint32_t index = y % sz; /* (7) */
if( !tr_bitfieldHas( a, index ) ) /* (8) */
{
tr_bitfieldAdd( a, index ); /* (9) */
++a_size;
}
}
tr_sha1( x, x, sizeof( x ), NULL ); /* (3) */
}
return a;
}
static int bandwidthPulse( void * vmgr );
tr_peerMgr*
tr_peerMgrNew( tr_session * session )
{
tr_peerMgr * m = tr_new0( tr_peerMgr, 1 );
m->session = session;
m->torrents = tr_ptrArrayNew( );
m->incomingHandshakes = tr_ptrArrayNew( );
m->bandwidthPulseNumber = -1;
m->bandwidthTimer = tr_timerNew( session, bandwidthPulse,
m, 1000 / BANDWIDTH_PULSES_PER_SECOND );
return m;
}
void
tr_peerMgrFree( tr_peerMgr * manager )
{
managerLock( manager );
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_ptrArrayFree( manager->incomingHandshakes, NULL );
/* free the torrents. */
tr_ptrArrayFree( manager->torrents, torrentDestructor );
managerUnlock( manager );
tr_free( manager );
}
static tr_peer**
getConnectedPeers( Torrent * t,
int * setmeCount )
{
int i, peerCount, connectionCount;
tr_peer **peers;
tr_peer **ret;
assert( torrentIsLocked( t ) );
peers = (tr_peer **) tr_ptrArrayPeek( t->peers, &peerCount );
ret = tr_new( tr_peer *, peerCount );
for( i = connectionCount = 0; i < peerCount; ++i )
if( peers[i]->msgs )
ret[connectionCount++] = peers[i];
*setmeCount = connectionCount;
return ret;
}
static int
clientIsDownloadingFrom( const tr_peer * peer )
{
return peer->clientIsInterested && !peer->clientIsChoked;
}
static int
clientIsUploadingTo( const tr_peer * peer )
{
return peer->peerIsInterested && !peer->peerIsChoked;
}
/***
****
***/
int
tr_peerMgrPeerIsSeed( const tr_peerMgr * mgr,
const uint8_t * torrentHash,
const struct in_addr * addr )
{
int isSeed = FALSE;
const Torrent * t = NULL;
const struct peer_atom * atom = NULL;
t = getExistingTorrent( (tr_peerMgr*)mgr, torrentHash );
if( t )
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;
tr_peer** peers;
assert( torrentIsLocked( t ) );
peers = getConnectedPeers( t, &peerCount );
/* 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 );
}
tr_free( peers );
*pieceCount = poolSize;
return pool;
}
struct tr_blockIterator
{
Torrent * t;
tr_block_index_t blockIndex, blockCount, *blocks;
tr_piece_index_t pieceIndex, pieceCount, *pieces;
};
static struct tr_blockIterator*
blockIteratorNew( Torrent * t )
{
struct tr_blockIterator * i = tr_new0( struct tr_blockIterator, 1 );
i->t = t;
i->pieces = getPreferredPieces( t, &i->pieceCount );
i->blocks = tr_new0( tr_block_index_t, t->tor->blockCount );
return i;
}
static int
blockIteratorNext( struct tr_blockIterator * i, tr_block_index_t * setme )
{
int 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_cpBlockIsComplete( tor->completion, block ) )
i->blocks[i->blockCount++] = block;
}
if(( found = ( i->blockIndex < i->blockCount )))
*setme = i->blocks[i->blockIndex++];
return found;
}
static void
blockIteratorFree( struct tr_blockIterator * i )
{
tr_free( i->blocks );
tr_free( i->pieces );
tr_free( i );
}
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
refillPulse( void * vtorrent )
{
tr_block_index_t block;
int peerCount;
int webseedCount;
tr_peer ** peers;
tr_webseed ** webseeds;
struct tr_blockIterator * blockIterator;
Torrent * t = vtorrent;
tr_torrent * tor = t->tor;
if( !t->isRunning )
return TRUE;
if( tr_torrentIsSeed( t->tor ) )
return TRUE;
torrentLock( t );
tordbg( t, "Refilling Request Buffers..." );
blockIterator = 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 )
&& blockIteratorNext( blockIterator, &block ) )
{
int j;
int 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 );
/* find a peer who can ask for this block */
for( j=0; !handled && j<peerCount; )
{
const int val = tr_peerMsgsAddRequest( peers[j]->msgs,
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 && j<webseedCount; )
{
const tr_addreq_t val = tr_webseedAddRequest( webseeds[j],
index, offset, length );
switch( val )
{
case TR_ADDREQ_FULL:
webseeds[j] = webseeds[--webseedCount];
break;
case TR_ADDREQ_OK:
incrementPieceRequests( t, index );
handled = TRUE;
break;
default:
assert( 0 && "unhandled value" );
break;
}
}
}
/* cleanup */
blockIteratorFree( blockIterator );
tr_free( webseeds );
tr_free( peers );
t->refillTimer = NULL;
torrentUnlock( t );
return FALSE;
}
static void
broadcastGotBlock( Torrent * t, uint32_t index, uint32_t offset, uint32_t length )
{
int i, size;
tr_peer ** peers;
assert( torrentIsLocked( t ) );
peers = getConnectedPeers( t, &size );
for( i=0; i<size; ++i )
tr_peerMsgsCancel( peers[i]->msgs, index, offset, length );
tr_free( peers );
}
static void
addStrike( Torrent * t,
tr_peer * peer )
{
tordbg( t, "increasing peer %s strike count to %d",
tr_peerIoAddrStr( &peer->in_addr,
peer->port ), peer->strikes + 1 );
if( ++peer->strikes >= MAX_BAD_PIECES_PER_PEER )
{
struct peer_atom * atom = getExistingAtom( t, &peer->in_addr );
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
peerCallbackFunc( void * vpeer,
void * vevent,
void * vt )
{
tr_peer * peer = vpeer; /* may be NULL if peer is a webseed */
Torrent * t = (Torrent *) vt;
const tr_peer_event * e = vevent;
torrentLock( t );
switch( e->eventType )
{
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;
tor->activityDate = now;
tor->uploadedCur += e->length;
tr_statsAddUploaded( tor->session, e->length );
if( peer )
{
struct peer_atom * a = getExistingAtom( t, &peer->in_addr );
a->piece_data_time = now;
}
break;
}
case TR_PEER_CLIENT_GOT_DATA:
{
const time_t now = time( NULL );
tr_torrent * tor = t->tor;
tor->activityDate = 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 )
tor->downloadedCur += e->length;
tr_statsAddDownloaded( tor->session, e->length );
if( peer ) {
struct peer_atom * a = getExistingAtom( t, &peer->in_addr );
a->piece_data_time = now;
}
break;
}
case TR_PEER_PEER_PROGRESS:
{
if( peer )
{
struct peer_atom * atom = getExistingAtom( t,
&peer->in_addr );
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 int ok = tr_ioTestPiece( tor, p );
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->session->peerMgr, tor->info.hash, p, ok );
if( !ok )
gotBadPiece( t, p );
else
{
int i, peerCount;
tr_peer ** peers = getConnectedPeers( t, &peerCount );
for( i = 0; i < peerCount; ++i )
tr_peerMsgsHave( peers[i]->msgs, p );
tr_free( peers );
}
tr_torrentRecheckCompleteness( tor );
}
break;
}
case TR_PEER_ERROR:
if( e->err == EINVAL )
{
addStrike( t, peer );
peer->doPurge = 1;
}
else if( ( e->err == ERANGE )
|| ( e->err == EMSGSIZE )
|| ( e->err == ENOTCONN ) )
{
/* some protocol error from the peer */
peer->doPurge = 1;
}
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 struct in_addr * addr,
uint16_t 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 int
myHandshakeDoneCB( tr_handshake * handshake,
tr_peerIo * io,
int isConnected,
const uint8_t * peer_id,
void * vmanager )
{
int ok = isConnected;
int success = FALSE;
uint16_t port;
const struct in_addr * addr;
tr_peerMgr * manager = (tr_peerMgr*) vmanager;
Torrent * t;
tr_handshake * ours;
assert( io );
assert( isConnected == 0 || isConnected == 1 );
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;
}
tr_peerIoFree( io );
}
else /* looking good */
{
struct peer_atom * atom;
ensureAtomExists( t, addr, port, 0, TR_PEER_FROM_INCOMING );
atom = getExistingAtom( t, addr );
atom->time = time( NULL );
if( atom->myflags & MYFLAG_BANNED )
{
tordbg( t, "banned peer %s tried to reconnect",
tr_peerIoAddrStr( &atom->addr,
atom->port ) );
tr_peerIoFree( io );
}
else if( tr_peerIoIsIncoming( io )
&& ( getPeerCount( t ) >= getMaxPeerCount( t->tor ) ) )
{
tr_peerIoFree( io );
}
else
{
tr_peer * peer = getExistingPeer( t, addr );
if( peer ) /* we already have this peer */
{
tr_peerIoFree( io );
}
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->io = io;
peer->msgs =
tr_peerMsgsNew( t->tor, peer, peerCallbackFunc, t,
&peer->msgsTag );
success = TRUE;
}
}
}
if( t )
torrentUnlock( t );
return success;
}
void
tr_peerMgrAddIncoming( tr_peerMgr * manager,
struct in_addr * addr,
uint16_t port,
int socket )
{
managerLock( manager );
if( tr_sessionIsAddressBlocked( manager->session, addr ) )
{
tr_dbg( "Banned IP address \"%s\" tried to connect to us",
inet_ntoa( *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, addr, port, socket );
handshake = tr_handshakeNew( io,
manager->session->encryptionMode,
myHandshakeDoneCB,
manager );
tr_ptrArrayInsertSorted( manager->incomingHandshakes, handshake,
handshakeCompare );
}
managerUnlock( manager );
}
void
tr_peerMgrAddPex( tr_peerMgr * manager,
const uint8_t * torrentHash,
uint8_t from,
const tr_pex * pex )
{
Torrent * t;
managerLock( manager );
t = getExistingTorrent( manager, torrentHash );
if( !tr_sessionIsAddressBlocked( t->manager->session, &pex->in_addr ) )
ensureAtomExists( t, &pex->in_addr, pex->port, pex->flags, from );
managerUnlock( 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 )
{
memcpy( &pex[i].in_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;
}
/**
***
**/
void
tr_peerMgrSetBlame( tr_peerMgr * manager,
const uint8_t * torrentHash,
tr_piece_index_t pieceIndex,
int success )
{
if( !success )
{
int peerCount, i;
Torrent * t = getExistingTorrent( manager, torrentHash );
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->in_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 =
memcmp( &a->in_addr, &b->in_addr, sizeof( struct in_addr ) );
if( i ) return i;
if( a->port < b->port ) return -1;
if( a->port > b->port ) return 1;
return 0;
}
int tr_pexCompare( const void * a,
const void * b );
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_peerMgr * manager,
const uint8_t * torrentHash,
tr_pex ** setme_pex )
{
int peerCount = 0;
const Torrent * t;
managerLock( manager );
t = getExistingTorrent( (tr_peerMgr*)manager, torrentHash );
if( !t )
{
*setme_pex = NULL;
}
else
{
int i;
const tr_peer ** peers = (const tr_peer **) tr_ptrArrayPeek( t->peers, &peerCount );
tr_pex * pex = tr_new( tr_pex, peerCount );
tr_pex * walk = pex;
for( i = 0; i < peerCount; ++i, ++walk )
{
const tr_peer * peer = peers[i];
walk->in_addr = peer->in_addr;
walk->port = peer->port;
walk->flags = 0;
if( peerPrefersCrypto( peer ) ) walk->flags |= ADDED_F_ENCRYPTION_FLAG;
if( peer->progress >= 1.0 ) walk->flags |= ADDED_F_SEED_FLAG;
}
assert( ( walk - pex ) == peerCount );
qsort( pex, peerCount, sizeof( tr_pex ), tr_pexCompare );
*setme_pex = pex;
}
managerUnlock( manager );
return peerCount;
}
static int reconnectPulse( void * vtorrent );
static int rechokePulse( void * vtorrent );
void
tr_peerMgrStartTorrent( tr_peerMgr * manager,
const uint8_t * torrentHash )
{
Torrent * t;
managerLock( manager );
t = getExistingTorrent( manager, torrentHash );
assert( t );
assert( ( t->isRunning != 0 ) == ( t->reconnectTimer != NULL ) );
assert( ( t->isRunning != 0 ) == ( t->rechokeTimer != NULL ) );
if( !t->isRunning )
{
t->isRunning = 1;
t->reconnectTimer = tr_timerNew( t->manager->session,
reconnectPulse, t,
RECONNECT_PERIOD_MSEC );
t->rechokeTimer = tr_timerNew( t->manager->session,
rechokePulse, t,
RECHOKE_PERIOD_MSEC );
reconnectPulse( t );
rechokePulse( t );
if( !tr_ptrArrayEmpty( t->webseeds ) )
refillSoon( t );
}
managerUnlock( manager );
}
static void
stopTorrent( Torrent * t )
{
assert( torrentIsLocked( t ) );
t->isRunning = 0;
tr_timerFree( &t->rechokeTimer );
tr_timerFree( &t->reconnectTimer );
/* 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_peerMgr * manager,
const uint8_t * torrentHash )
{
managerLock( manager );
stopTorrent( getExistingTorrent( manager, torrentHash ) );
managerUnlock( manager );
}
void
tr_peerMgrAddTorrent( tr_peerMgr * manager,
tr_torrent * tor )
{
Torrent * t;
managerLock( manager );
assert( tor );
assert( getExistingTorrent( manager, tor->info.hash ) == NULL );
t = torrentConstructor( manager, tor );
tr_ptrArrayInsertSorted( manager->torrents, t, torrentCompare );
managerUnlock( manager );
}
void
tr_peerMgrRemoveTorrent( tr_peerMgr * manager,
const uint8_t * torrentHash )
{
Torrent * t;
managerLock( manager );
t = getExistingTorrent( manager, torrentHash );
assert( t );
stopTorrent( t );
tr_ptrArrayRemoveSorted( manager->torrents, t, torrentCompare );
torrentDestructor( t );
managerUnlock( manager );
}
void
tr_peerMgrTorrentAvailability( const tr_peerMgr * manager,
const uint8_t * torrentHash,
int8_t * tab,
unsigned int tabCount )
{
tr_piece_index_t i;
const Torrent * t;
const tr_torrent * tor;
float interval;
int isComplete;
int peerCount;
const tr_peer ** peers;
managerLock( manager );
t = getExistingTorrent( (tr_peerMgr*)manager, torrentHash );
tor = t->tor;
interval = tor->info.pieceCount / (float)tabCount;
isComplete = tor
&& ( tr_cpGetStatus ( tor->completion ) == TR_CP_COMPLETE );
peers = (const tr_peer **) tr_ptrArrayPeek( t->peers, &peerCount );
memset( tab, 0, tabCount );
for( i = 0; tor && i < tabCount; ++i )
{
const int piece = i * interval;
if( isComplete || 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];
}
}
managerUnlock( manager );
}
/* Returns the pieces that are available from peers */
tr_bitfield*
tr_peerMgrGetAvailable( const tr_peerMgr * manager,
const uint8_t * torrentHash )
{
int i, size;
Torrent * t;
tr_peer ** peers;
tr_bitfield * pieces;
managerLock( manager );
t = getExistingTorrent( (tr_peerMgr*)manager, torrentHash );
pieces = tr_bitfieldNew( t->tor->info.pieceCount );
peers = getConnectedPeers( t, &size );
for( i = 0; i < size; ++i )
tr_bitfieldOr( pieces, peers[i]->have );
managerUnlock( manager );
tr_free( peers );
return pieces;
}
int
tr_peerMgrHasConnections( const tr_peerMgr * manager,
const uint8_t * torrentHash )
{
int ret;
const Torrent * t;
managerLock( manager );
t = getExistingTorrent( (tr_peerMgr*)manager, torrentHash );
ret = t && ( !tr_ptrArrayEmpty( t->peers )
|| !tr_ptrArrayEmpty( t->webseeds ) );
managerUnlock( manager );
return ret;
}
void
tr_peerMgrTorrentStats( const tr_peerMgr * manager,
const uint8_t * torrentHash,
int * setmePeersKnown,
int * setmePeersConnected,
int * setmeSeedsConnected,
int * setmeWebseedsSendingToUs,
int * setmePeersSendingToUs,
int * setmePeersGettingFromUs,
int * setmePeersFrom )
{
int i, size;
const Torrent * t;
const tr_peer ** peers;
const tr_webseed ** webseeds;
managerLock( manager );
t = getExistingTorrent( (tr_peerMgr*)manager, torrentHash );
peers = (const tr_peer **) tr_ptrArrayPeek( t->peers, &size );
*setmePeersKnown = tr_ptrArraySize( t->pool );
*setmePeersConnected = 0;
*setmeSeedsConnected = 0;
*setmePeersGettingFromUs = 0;
*setmePeersSendingToUs = 0;
*setmeWebseedsSendingToUs = 0;
for( i = 0; i < TR_PEER_FROM__MAX; ++i )
setmePeersFrom[i] = 0;
for( i = 0; i < size; ++i )
{
const tr_peer * peer = peers[i];
const struct peer_atom * atom = getExistingAtom( t, &peer->in_addr );
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_ptrArrayPeek( t->webseeds, &size );
for( i = 0; i < size; ++i )
{
if( tr_webseedIsActive( webseeds[i] ) )
++ * setmeWebseedsSendingToUs;
}
managerUnlock( manager );
}
double
tr_peerMgrGetRate( const tr_peerMgr * manager,
tr_direction direction )
{
int i;
double bytes = 0;
assert( manager != NULL );
assert( direction == TR_UP || direction == TR_DOWN );
for( i = 0; i < BANDWIDTH_PULSE_HISTORY; ++i )
bytes += manager->rateHistory[direction][i];
return ( BANDWIDTH_PULSES_PER_SECOND * bytes )
/ ( BANDWIDTH_PULSE_HISTORY * 1024 );
}
float*
tr_peerMgrWebSpeeds( const tr_peerMgr * manager,
const uint8_t * torrentHash )
{
const Torrent * t;
const tr_webseed ** webseeds;
int i;
int webseedCount;
float * ret;
assert( manager );
managerLock( manager );
t = getExistingTorrent( (tr_peerMgr*)manager, torrentHash );
webseeds = (const tr_webseed**) tr_ptrArrayPeek( t->webseeds,
&webseedCount );
assert( webseedCount == t->tor->info.webseedCount );
ret = tr_new0( float, webseedCount );
for( i = 0; i < webseedCount; ++i )
if( !tr_webseedGetSpeed( webseeds[i], &ret[i] ) )
ret[i] = -1.0;
managerUnlock( manager );
return ret;
}
struct tr_peer_stat *
tr_peerMgrPeerStats( const tr_peerMgr * manager,
const uint8_t * torrentHash,
int * setmeCount UNUSED )
{
int i, size;
const Torrent * t;
tr_peer ** peers;
tr_peer_stat * ret;
assert( manager );
managerLock( manager );
t = getExistingTorrent( (tr_peerMgr*)manager, torrentHash );
peers = getConnectedPeers( (Torrent*)t, &size );
ret = tr_new0( tr_peer_stat, size );
for( i = 0; i < size; ++i )
{
char * pch;
const tr_peer * peer = peers[i];
const struct peer_atom * atom = getExistingAtom( t, &peer->in_addr );
tr_peer_stat * stat = ret + i;
tr_netNtop( &peer->in_addr, stat->addr, sizeof( stat->addr ) );
tr_strlcpy( stat->client, ( peer->client ? peer->client : "" ),
sizeof( stat->client ) );
stat->port = peer->port;
stat->from = atom->from;
stat->progress = peer->progress;
stat->isEncrypted = tr_peerIoIsEncrypted( peer->io ) ? 1 : 0;
stat->rateToPeer = tr_peerIoGetRateToPeer( peer->io );
stat->rateToClient = tr_peerIoGetRateToClient( peer->io );
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 );
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;
tr_free( peers );
managerUnlock( manager );
return ret;
}
/**
***
**/
struct ChokeData
{
unsigned int doUnchoke : 1;
unsigned int isInterested : 1;
double rateToClient;
double rateToPeer;
tr_peer * peer;
};
static int
tr_compareDouble( double a,
double b )
{
if( a < b ) return -1;
if( a > b ) return 1;
return 0;
}
static int
compareChoke( const void * va,
const void * vb )
{
const struct ChokeData * a = va;
const struct ChokeData * b = vb;
int diff = 0;
if( diff == 0 ) /* prefer higher dl speeds */
diff = -tr_compareDouble( a->rateToClient, b->rateToClient );
if( diff == 0 ) /* prefer higher ul speeds */
diff = -tr_compareDouble( a->rateToPeer, b->rateToPeer );
if( diff == 0 ) /* prefer unchoked */
diff = (int)a->peer->peerIsChoked - (int)b->peer->peerIsChoked;
return diff;
}
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
rechoke( Torrent * t )
{
int i, peerCount, size, unchokedInterested;
tr_peer ** peers = getConnectedPeers( t, &peerCount );
struct ChokeData * choke = tr_new0( struct ChokeData, peerCount );
assert( torrentIsLocked( t ) );
/* sort the peers by preference and rate */
for( i = 0, size = 0; i < peerCount; ++i )
{
tr_peer * peer = peers[i];
if( peer->progress >= 1.0 ) /* choke all seeds */
tr_peerMsgsSetChoke( peer->msgs, TRUE );
else
{
struct ChokeData * node = &choke[size++];
node->peer = peer;
node->isInterested = peer->peerIsInterested;
node->rateToClient = tr_peerIoGetRateToClient( peer->io );
node->rateToPeer = tr_peerIoGetRateToPeer( peer->io );
}
}
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; i < size && unchokedInterested < MAX_UNCHOKED_PEERS; ++i )
{
choke[i].doUnchoke = 1;
if( choke[i].isInterested )
++unchokedInterested;
}
/* optimistic unchoke */
if( i < size )
{
int n;
struct ChokeData * c;
tr_ptrArray * randPool = tr_ptrArrayNew( );
for( ; i < size; ++i )
{
if( choke[i].isInterested )
{
const tr_peer * peer = choke[i].peer;
int x = 1, y;
if( isNew( peer ) ) x *= 3;
if( isSame( peer ) ) x *= 3;
for( y = 0; y < x; ++y )
tr_ptrArrayAppend( randPool, &choke[i] );
}
}
if( ( n = tr_ptrArraySize( randPool ) ) )
{
c = tr_ptrArrayNth( randPool, tr_cryptoWeakRandInt( n ) );
c->doUnchoke = 1;
t->optimistic = c->peer;
}
tr_ptrArrayFree( randPool, NULL );
}
for( i = 0; i < size; ++i )
tr_peerMsgsSetChoke( choke[i].peer->msgs, !choke[i].doUnchoke );
/* cleanup */
tr_free( choke );
tr_free( peers );
}
static int
rechokePulse( void * vtorrent )
{
Torrent * t = vtorrent;
torrentLock( t );
rechoke( t );
torrentUnlock( t );
return TRUE;
}
/***
****
**** Life and Death
****
***/
static int
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 = getExistingAtom( t, &peer->in_addr );
/* 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 TRUE;
}
/* 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 TRUE;
}
}
/* 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 = lo + ( ( hi - lo ) * strictness );
const time_t then = peer->pieceDataActivityDate;
const int idleTime = then ? ( now - then ) : 0;
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 TRUE;
}
}
return FALSE;
}
static tr_peer **
getPeersToClose( Torrent * t,
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 ) )
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;
/* <Charles> 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;
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 ) )
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 int
reconnectPulse( void * vtorrent )
{
Torrent * t = vtorrent;
static time_t prevTime = 0;
static int newConnectionsThisSecond = 0;
time_t now;
torrentLock( t );
now = time( NULL );
if( prevTime != now )
{
prevTime = now;
newConnectionsThisSecond = 0;
}
if( !t->isRunning )
{
removeAllPeers( t );
}
else
{
int i, nCandidates, nBad;
struct peer_atom ** candidates = getPeerCandidates( t, &nCandidates );
struct tr_peer ** connections = getPeersToClose( t, &nBad );
if( nBad || nCandidates )
tordbg(
t, "reconnect pulse for [%s]: %d bad connections, "
"%d connection candidates, %d atoms, max per pulse is %d",
t->tor->info.name, nBad, nCandidates,
tr_ptrArraySize( t->pool ),
(int)MAX_RECONNECTIONS_PER_PULSE );
/* disconnect some peers.
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 */
for( i = 0; i < nBad; ++i )
{
tr_peer * peer = connections[i];
struct peer_atom * atom = getExistingAtom( t, &peer->in_addr );
if( peer->pieceDataActivityDate )
atom->numFails = 0;
else
++atom->numFails;
tordbg( t, "removing bad peer %s",
tr_peerIoGetAddrStr( peer->io ) );
removePeer( t, peer );
}
/* add some new ones */
for( i = 0; ( i < nCandidates )
&& ( i < MAX_RECONNECTIONS_PER_PULSE )
&& ( getPeerCount( t ) < getMaxPeerCount( t->tor ) )
&& ( newConnectionsThisSecond < MAX_CONNECTIONS_PER_SECOND );
++i )
{
tr_peerMgr * mgr = t->manager;
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, &atom->addr, atom->port,
t->hash );
if( io == NULL )
{
atom->myflags |= MYFLAG_UNREACHABLE;
}
else
{
tr_handshake * handshake = tr_handshakeNew(
io,
mgr->session->
encryptionMode,
myHandshakeDoneCB,
mgr );
assert( tr_peerIoGetTorrentHash( io ) );
++newConnectionsThisSecond;
tr_ptrArrayInsertSorted( t->outgoingHandshakes, handshake,
handshakeCompare );
}
atom->time = time( NULL );
}
/* cleanup */
tr_free( connections );
tr_free( candidates );
}
torrentUnlock( t );
return TRUE;
}
/****
*****
***** BANDWIDTH ALLOCATION
*****
****/
static double
allocateHowMuch( double desiredAvgKB,
const double * history )
{
const double baseline = desiredAvgKB * 1024.0 /
BANDWIDTH_PULSES_PER_SECOND;
const double min = baseline * 0.66;
const double max = baseline * 1.33;
int i;
double usedBytes;
double n;
double clamped;
for( usedBytes = i = 0; i < BANDWIDTH_PULSE_HISTORY; ++i )
usedBytes += history[i];
n = ( desiredAvgKB * 1024.0 )
* ( BANDWIDTH_PULSE_HISTORY + 1.0 )
/ BANDWIDTH_PULSES_PER_SECOND
- usedBytes;
/* clamp the return value to lessen oscillation */
clamped = n;
clamped = MAX( clamped, min );
clamped = MIN( clamped, max );
/*fprintf( stderr, "desiredAvgKB is %.2f, rate is %.2f, allocating %.2f
(%.2f)\n", desiredAvgKB,
((usedBytes*BANDWIDTH_PULSES_PER_SECOND)/BANDWIDTH_PULSE_HISTORY)/1024.0,
clamped/1024.0, n/1024.0 );*/
return clamped;
}
/**
* Distributes a fixed amount of bandwidth among a set of peers.
*
* @param peerArray peers whose client-to-peer bandwidth will be set
* @param direction whether to allocate upload or download bandwidth
* @param history recent bandwidth history for these peers
* @param desiredAvgKB overall bandwidth goal for this set of peers
*/
static void
setPeerBandwidth( tr_ptrArray * peerArray,
const tr_direction direction,
const double * history,
double desiredAvgKB )
{
const int peerCount = tr_ptrArraySize( peerArray );
const double bytes = allocateHowMuch( desiredAvgKB, history );
const double welfareBytes = MIN( 2048, bytes * 0.2 );
const double meritBytes = MAX( 0, bytes - welfareBytes );
tr_peer ** peers = (tr_peer**) tr_ptrArrayBase( peerArray );
tr_peer ** candidates = tr_new( tr_peer *, peerCount );
int i;
int candidateCount;
double welfare;
size_t bytesUsed;
assert( meritBytes >= 0.0 );
assert( welfareBytes >= 0.0 );
assert( direction == TR_UP || direction == TR_DOWN );
for( i = candidateCount = 0; i < peerCount; ++i )
if( tr_peerIoWantsBandwidth( peers[i]->io, direction ) )
candidates[candidateCount++] = peers[i];
else
tr_peerIoSetBandwidth( peers[i]->io, direction, 0 );
for( i = bytesUsed = 0; i < candidateCount; ++i )
bytesUsed += tr_peerIoGetBandwidthUsed( candidates[i]->io,
direction );
welfare = welfareBytes / candidateCount;
for( i = 0; i < candidateCount; ++i )
{
tr_peer * peer = candidates[i];
const double merit = bytesUsed
? ( meritBytes *
tr_peerIoGetBandwidthUsed( peer->io,
direction ) ) /
bytesUsed
: ( meritBytes / candidateCount );
tr_peerIoSetBandwidth( peer->io, direction, merit + welfare );
}
/* cleanup */
tr_free( candidates );
}
static size_t
countHandshakeBandwidth( tr_ptrArray * handshakes,
tr_direction direction )
{
const int n = tr_ptrArraySize( handshakes );
int i;
size_t total;
for( i = total = 0; i < n; ++i )
{
tr_peerIo * io = tr_handshakeGetIO( tr_ptrArrayNth( handshakes, i ) );
total += tr_peerIoGetBandwidthUsed( io, direction );
}
return total;
}
static size_t
countPeerBandwidth( tr_ptrArray * peers,
tr_direction direction )
{
const int n = tr_ptrArraySize( peers );
int i;
size_t total;
for( i = total = 0; i < n; ++i )
{
tr_peer * peer = tr_ptrArrayNth( peers, i );
total += tr_peerIoGetBandwidthUsed( peer->io, direction );
}
return total;
}
static void
givePeersUnlimitedBandwidth( tr_ptrArray * peers,
tr_direction direction )
{
const int n = tr_ptrArraySize( peers );
int i;
for( i = 0; i < n; ++i )
{
tr_peer * peer = tr_ptrArrayNth( peers, i );
tr_peerIoSetBandwidthUnlimited( peer->io, direction );
}
}
static void
pumpAllPeers( tr_peerMgr * mgr )
{
const int torrentCount = tr_ptrArraySize( mgr->torrents );
int i, j;
for( i = 0; i < torrentCount; ++i )
{
Torrent * t = tr_ptrArrayNth( mgr->torrents, i );
for( j = 0; j < tr_ptrArraySize( t->peers ); ++j )
{
tr_peer * peer = tr_ptrArrayNth( t->peers, j );
tr_peerMsgsPulse( peer->msgs );
}
}
}
/**
* Allocate bandwidth for each peer connection.
*
* @param mgr the peer manager
* @param direction whether to allocate upload or download bandwidth
* @return the amount of directional bandwidth used since the last pulse.
*/
static double
allocateBandwidth( tr_peerMgr * mgr,
tr_direction direction )
{
tr_session * session = mgr->session;
const int pulseNumber = mgr->bandwidthPulseNumber;
const int torrentCount = tr_ptrArraySize( mgr->torrents );
Torrent ** torrents = (Torrent **) tr_ptrArrayBase( mgr->torrents );
tr_ptrArray * globalPool = tr_ptrArrayNew( );
double allBytesUsed = 0;
size_t poolBytesUsed = 0;
int i;
assert( mgr );
assert( direction == TR_UP || direction == TR_DOWN );
/* before allocating bandwidth, pump the connected peers */
pumpAllPeers( mgr );
for( i = 0; i < torrentCount; ++i )
{
Torrent * t = torrents[i];
const size_t used = countPeerBandwidth( t->peers, direction );
countHandshakeBandwidth( t->outgoingHandshakes, direction );
/* remember this torrent's bytes used */
t->tor->rateHistory[direction][pulseNumber] = used;
/* add this torrent's bandwidth use to allBytesUsed */
allBytesUsed += used;
/* process the torrent's peers based on its speed mode */
switch( tr_torrentGetSpeedMode( t->tor, direction ) )
{
case TR_SPEEDLIMIT_UNLIMITED:
givePeersUnlimitedBandwidth( t->peers, direction );
break;
case TR_SPEEDLIMIT_SINGLE:
setPeerBandwidth( t->peers, direction,
t->tor->rateHistory[direction],
tr_torrentGetSpeedLimit( t->tor,
direction ) );
break;
case TR_SPEEDLIMIT_GLOBAL:
{
int i;
const int n = tr_ptrArraySize( t->peers );
for( i = 0; i < n; ++i )
tr_ptrArrayAppend( globalPool,
tr_ptrArrayNth( t->peers, i ) );
poolBytesUsed += used;
break;
}
}
}
/* add incoming handshakes to the global pool */
i = countHandshakeBandwidth( mgr->incomingHandshakes, direction );
allBytesUsed += i;
poolBytesUsed += i;
mgr->globalPoolHistory[direction][pulseNumber] = poolBytesUsed;
/* handle the global pool's connections */
if( !tr_sessionIsSpeedLimitEnabled( session, direction ) )
givePeersUnlimitedBandwidth( globalPool, direction );
else
setPeerBandwidth( globalPool, direction,
mgr->globalPoolHistory[direction],
tr_sessionGetSpeedLimit( session, direction ) );
/* now that we've allocated bandwidth, pump all the connected peers */
pumpAllPeers( mgr );
/* cleanup */
tr_ptrArrayFree( globalPool, NULL );
return allBytesUsed;
}
static int
bandwidthPulse( void * vmgr )
{
tr_peerMgr * mgr = vmgr;
int i;
managerLock( mgr );
/* keep track of how far we are into the cycle */
if( ++mgr->bandwidthPulseNumber == BANDWIDTH_PULSE_HISTORY )
mgr->bandwidthPulseNumber = 0;
/* allocate the upload and download bandwidth */
for( i = 0; i < 2; ++i )
mgr->rateHistory[i][mgr->bandwidthPulseNumber] =
allocateBandwidth( mgr, i );
managerUnlock( mgr );
return TRUE;
}