mirror
/
transmission
mirror of https://github.com/transmission/transmission
1
0
Fork 0
Code Issues Releases Wiki Activity
transmission/libtransmission/peer.c

585 lines
15 KiB
C
Raw Blame History

/******************************************************************************
* $Id$
*
* Copyright (c) 2005-2006 Transmission authors and contributors
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS IN THE SOFTWARE.
*****************************************************************************/
#include "transmission.h"
#define MAX_REQUEST_COUNT 32
#define OUR_REQUEST_COUNT 8 /* TODO: we should detect if we are on a
high-speed network and adapt */
typedef struct tr_request_s
{
int index;
int begin;
int length;
} tr_request_t;
struct tr_peer_s
{
struct in_addr addr;
in_port_t port;
#define PEER_STATUS_IDLE 1 /* Need to connect */
#define PEER_STATUS_CONNECTING 2 /* Trying to send handshake */
#define PEER_STATUS_HANDSHAKE 4 /* Waiting for peer's handshake */
#define PEER_STATUS_CONNECTED 8 /* Got peer's handshake */
int status;
int socket;
uint64_t date;
uint64_t keepAlive;
char amChoking;
char amInterested;
char peerChoking;
char peerInterested;
int optimistic;
uint64_t lastChoke;
uint8_t id[20];
/* The pieces that the peer has */
uint8_t * bitfield;
int goodPcs;
int badPcs;
int banned;
/* The pieces that the peer is contributing to */
uint8_t * blamefield;
/* The bad pieces that the peer has contributed to */
uint8_t * banfield;
uint8_t * buf;
int size;
int pos;
uint8_t * outMessages;
int outMessagesSize;
int outMessagesPos;
uint8_t outBlock[13+16384];
int outBlockSize;
int outBlockLoaded;
int outBlockSending;
int inRequestCount;
tr_request_t inRequests[OUR_REQUEST_COUNT];
int inIndex;
int inBegin;
int inLength;
uint64_t inTotal;
int outRequestCount;
tr_request_t outRequests[MAX_REQUEST_COUNT];
uint64_t outTotal;
uint64_t outDate;
int outSlow;
tr_ratecontrol_t * download;
};
#define peer_dbg( a... ) __peer_dbg( peer, ## a )
static void __peer_dbg( tr_peer_t * peer, char * msg, ... )
{
char string[256];
va_list args;
va_start( args, msg );
sprintf( string, "%08x:%04x ",
(uint32_t) peer->addr.s_addr, peer->port );
vsnprintf( &string[14], sizeof( string ) - 14, msg, args );
va_end( args );
tr_dbg( "%s", string );
}
#include "peermessages.h"
#include "peerutils.h"
#include "peerparse.h"
/***********************************************************************
* tr_peerAddOld
***********************************************************************
* Tries to add a peer given its IP and port (received from a tracker
* which doesn't support the "compact" extension).
**********************************************************************/
void tr_peerAddOld( tr_torrent_t * tor, char * ip, int port )
{
struct in_addr addr;
if( tr_netResolve( ip, &addr ) )
{
return;
}
addWithAddr( tor, addr, htons( port ) );
}
/***********************************************************************
* tr_peerAddCompact
***********************************************************************
* Tries to add a peer, using 'addr' and 'port' to connect to the peer.
**********************************************************************/
void tr_peerAddCompact( tr_torrent_t * tor, struct in_addr addr,
in_port_t port )
{
addWithAddr( tor, addr, port );
}
/***********************************************************************
* tr_peerInit
***********************************************************************
* Initializes a new peer.
**********************************************************************/
tr_peer_t * tr_peerInit( struct in_addr addr, in_port_t port, int s )
{
tr_peer_t * peer = peerInit();
peer->socket = s;
peer->addr = addr;
peer->port = port;
peer->status = PEER_STATUS_CONNECTING;
return peer;
}
void tr_peerAttach( tr_torrent_t * tor, tr_peer_t * peer )
{
peerAttach( tor, peer );
}
void tr_peerDestroy( tr_fd_t * fdlimit, tr_peer_t * peer )
{
if( peer->bitfield )
{
free( peer->bitfield );
}
if( peer->blamefield )
{
free( peer->blamefield );
}
if( peer->banfield )
{
free( peer->banfield );
}
if( peer->buf )
{
free( peer->buf );
}
if( peer->outMessages )
{
free( peer->outMessages );
}
if( peer->status > PEER_STATUS_IDLE )
{
tr_netClose( peer->socket );
tr_fdSocketClosed( fdlimit, 0 );
}
tr_rcClose( peer->download );
free( peer );
}
/***********************************************************************
* tr_peerRem
***********************************************************************
* Frees and closes everything related to the peer at index 'i', and
* removes it from the peers list.
**********************************************************************/
void tr_peerRem( tr_torrent_t * tor, int i )
{
tr_peer_t * peer = tor->peers[i];
int j;
for( j = 0; j < peer->inRequestCount; j++ )
{
tr_request_t * r;
int block;
r = &peer->inRequests[j];
block = tr_block( r->index,r->begin );
tr_cpDownloaderRem( tor->completion, block );
}
tr_peerDestroy( tor->fdlimit, peer );
tor->peerCount--;
memmove( &tor->peers[i], &tor->peers[i+1],
( tor->peerCount - i ) * sizeof( tr_peer_t * ) );
}
/***********************************************************************
* tr_peerRead
***********************************************************************
*
**********************************************************************/
int tr_peerRead( tr_torrent_t * tor, tr_peer_t * peer )
{
int ret;
/* Try to read */
for( ;; )
{
if( tor && !tr_rcCanTransfer( tor->globalDownload ) )
{
break;
}
if( peer->size < 1 )
{
peer->size = 1024;
peer->buf = malloc( peer->size );
}
else if( peer->pos >= peer->size )
{
peer->size *= 2;
peer->buf = realloc( peer->buf, peer->size );
}
/* Never read more than 1K each time, otherwise the rate
control is no use */
ret = tr_netRecv( peer->socket, &peer->buf[peer->pos],
MIN( 1024, peer->size - peer->pos ) );
if( ret & TR_NET_CLOSE )
{
peer_dbg( "connection closed" );
return 1;
}
else if( ret & TR_NET_BLOCK )
{
break;
}
peer->date = tr_date();
peer->pos += ret;
if( NULL != tor )
{
tr_rcTransferred( peer->download, ret );
tr_rcTransferred( tor->download, ret );
tr_rcTransferred( tor->globalDownload, ret );
if( parseBuf( tor, peer ) )
{
return 1;
}
}
else
{
if( parseBufHeader( peer ) )
{
return 1;
}
}
}
return 0;
}
uint64_t tr_peerDate( tr_peer_t * peer )
{
return peer->date;
}
/***********************************************************************
* tr_peerHash
***********************************************************************
*
**********************************************************************/
uint8_t * tr_peerHash( tr_peer_t * peer )
{
return parseBufHash( peer );
}
/***********************************************************************
* tr_peerPulse
***********************************************************************
*
**********************************************************************/
void tr_peerPulse( tr_torrent_t * tor )
{
int i, ret, size;
uint8_t * p;
tr_peer_t * peer;
if( tr_date() > tor->date + 1000 )
{
tor->date = tr_date();
for( i = 0; i < tor->peerCount; )
{
if( checkPeer( tor, i ) )
{
tr_peerRem( tor, i );
continue;
}
i++;
}
}
if( tor->status & TR_STATUS_STOPPING )
{
return;
}
/* Shuffle peers */
if( tor->peerCount > 1 )
{
peer = tor->peers[0];
memmove( &tor->peers[0], &tor->peers[1],
( tor->peerCount - 1 ) * sizeof( void * ) );
tor->peers[tor->peerCount - 1] = peer;
}
/* Handle peers */
for( i = 0; i < tor->peerCount; )
{
peer = tor->peers[i];
if( peer->status < PEER_STATUS_HANDSHAKE )
{
i++;
continue;
}
if( tr_peerRead( tor, tor->peers[i] ) )
{
goto dropPeer;
}
if( peer->status < PEER_STATUS_CONNECTED )
{
i++;
continue;
}
/* Try to write */
writeBegin:
/* Send all smaller messages regardless of the upload cap */
while( ( p = messagesPending( peer, &size ) ) )
{
ret = tr_netSend( peer->socket, p, size );
if( ret & TR_NET_CLOSE )
{
goto dropPeer;
}
else if( ret & TR_NET_BLOCK )
{
goto writeEnd;
}
messagesSent( peer, ret );
}
/* Send pieces if we can */
while( ( p = blockPending( tor, peer, &size ) ) )
{
if( !tr_rcCanTransfer( tor->globalUpload ) )
{
break;
}
ret = tr_netSend( peer->socket, p, size );
if( ret & TR_NET_CLOSE )
{
goto dropPeer;
}
else if( ret & TR_NET_BLOCK )
{
break;
}
blockSent( peer, ret );
tr_rcTransferred( tor->upload, ret );
tr_rcTransferred( tor->globalUpload, ret );
tor->uploaded += ret;
peer->outTotal += ret;
peer->outDate = tr_date();
/* In case this block is done, you may have messages
pending. Send them before we start the next block */
goto writeBegin;
}
writeEnd:
/* Ask for a block whenever possible */
if( !tr_cpIsSeeding( tor->completion ) &&
!peer->amInterested && tor->peerCount > TR_MAX_PEER_COUNT - 2 )
{
/* This peer is no use to us, and it seems there are
more */
peer_dbg( "not interesting" );
tr_peerRem( tor, i );
continue;
}
if( peer->amInterested && !peer->peerChoking && !peer->banned )
{
int block;
while( peer->inRequestCount < OUR_REQUEST_COUNT )
{
block = chooseBlock( tor, peer );
if( block < 0 )
{
break;
}
sendRequest( tor, peer, block );
}
}
i++;
continue;
dropPeer:
tr_peerRem( tor, i );
}
}
/***********************************************************************
* tr_peerIsConnected
***********************************************************************
*
**********************************************************************/
int tr_peerIsConnected( tr_peer_t * peer )
{
return peer->status & PEER_STATUS_CONNECTED;
}
/***********************************************************************
* tr_peerIsUploading
***********************************************************************
*
**********************************************************************/
int tr_peerIsUploading( tr_peer_t * peer )
{
return ( peer->inRequestCount > 0 );
}
/***********************************************************************
* tr_peerIsDownloading
***********************************************************************
*
**********************************************************************/
int tr_peerIsDownloading( tr_peer_t * peer )
{
return peer->outBlockSending;
}
/***********************************************************************
* tr_peerBitfield
***********************************************************************
*
**********************************************************************/
uint8_t * tr_peerBitfield( tr_peer_t * peer )
{
return peer->bitfield;
}
float tr_peerDownloadRate( tr_peer_t * peer )
{
return tr_rcRate( peer->download );
}
int tr_peerIsUnchoked( tr_peer_t * peer )
{
return !peer->amChoking;
}
int tr_peerIsInterested ( tr_peer_t * peer )
{
return peer->peerInterested;
}
void tr_peerChoke( tr_peer_t * peer )
{
sendChoke( peer, 1 );
peer->lastChoke = tr_date();
}
void tr_peerUnchoke( tr_peer_t * peer )
{
sendChoke( peer, 0 );
peer->lastChoke = tr_date();
}
uint64_t tr_peerLastChoke( tr_peer_t * peer )
{
return peer->lastChoke;
}
void tr_peerSetOptimistic( tr_peer_t * peer, int o )
{
peer->optimistic = o;
}
int tr_peerIsOptimistic( tr_peer_t * peer )
{
return peer->optimistic;
}
static inline int peerIsBad( tr_peer_t * peer )
{
return ( peer->badPcs > 4 + 2 * peer->goodPcs );
}
static inline int peerIsGood( tr_peer_t * peer )
{
return ( peer->goodPcs > 3 * peer->badPcs );
}
void tr_peerBlame( tr_torrent_t * tor, tr_peer_t * peer,
int piece, int success )
{
if( !peer->blamefield || !tr_bitfieldHas( peer->blamefield, piece ) )
{
return;
}
if( success )
{
peer->goodPcs++;
if( peer->banfield && peerIsGood( peer ) )
{
/* Assume the peer wasn't responsible for the bad pieces
we was banned for */
memset( peer->banfield, 0x00, ( tor->info.pieceCount + 7 ) / 8 );
}
}
else
{
peer->badPcs++;
/* Ban the peer for this piece */
if( !peer->banfield )
{
peer->banfield = calloc( ( tor->info.pieceCount + 7 ) / 8, 1 );
}
tr_bitfieldAdd( peer->banfield, piece );
if( peerIsBad( peer ) )
{
/* Full ban */
peer_dbg( "banned (%d / %d)", peer->goodPcs, peer->badPcs );
peer->banned = 1;
peer->peerInterested = 0;
}
}
tr_bitfieldRem( peer->blamefield, piece );
}
Reference in New Issue View Git Blame Copy Permalink