transmission/libtransmission/peer-io.c

580 lines
12 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 <string.h>
#include <stdio.h>
#include <unistd.h>
#include <netinet/in.h> /* struct in_addr */
#include <arpa/inet.h> /* inet_ntoa */
#include <event.h>
#include "transmission.h"
#include "crypto.h"
#include "net.h"
#include "peer-io.h"
#include "ratecontrol.h"
#include "trevent.h"
#include "utils.h"
#define IO_TIMEOUT_SECS 8
/* arbitrary */
#define TR_RDBUF (1024*8)
/**
***
**/
struct tr_extensions
{
unsigned int extendedProtocolSupported : 1;
unsigned int fastPeersSupported : 1;
};
struct tr_peerIo
{
struct tr_handle * handle;
struct in_addr in_addr;
int port;
int socket;
int encryptionMode;
int timeout;
struct bufferevent * bufev;
uint8_t peerId[20];
tr_extensions extensions;
unsigned int isEncrypted : 1;
unsigned int isIncoming : 1;
unsigned int peerIdIsSet : 1;
tr_can_read_cb canRead;
tr_did_write_cb didWrite;
tr_net_error_cb gotError;
void * userData;
tr_crypto * crypto;
};
/**
***
**/
static void
didWriteWrapper( struct bufferevent * e, void * userData )
{
tr_peerIo * c = (tr_peerIo *) userData;
if( c->didWrite != NULL )
(*c->didWrite)( e, c->userData );
}
static void
canReadWrapper( struct bufferevent * e, void * userData )
{
int done = 0;
tr_peerIo * c = userData;
tr_handle * handle = c->handle;
if( c->canRead == NULL )
return;
tr_globalLock( handle );
while( !done )
{
const int ret = (*c->canRead)( e, c->userData );
switch( ret )
{
case READ_AGAIN:
if( EVBUFFER_LENGTH( e->input ) )
continue;
case READ_MORE:
case READ_DONE:
done = 1;
}
}
tr_globalUnlock( handle );
}
static void
gotErrorWrapper( struct bufferevent * e, short what, void * userData )
{
tr_peerIo * c = userData;
if( c->gotError != NULL )
(*c->gotError)( e, what, c->userData );
}
/**
***
**/
void bufferevent_setwatermark(struct bufferevent *, short, size_t, size_t);
static tr_peerIo*
tr_peerIoNew( struct tr_handle * handle,
const struct in_addr * in_addr,
uint16_t port,
const uint8_t * torrentHash,
int isIncoming,
int socket )
{
tr_peerIo * c;
c = tr_new0( tr_peerIo, 1 );
c->crypto = tr_cryptoNew( torrentHash, isIncoming );
c->handle = handle;
c->in_addr = *in_addr;
c->port = port;
c->socket = socket;
c->isIncoming = isIncoming ? 1 : 0;
c->timeout = IO_TIMEOUT_SECS;
c->bufev = bufferevent_new( c->socket,
canReadWrapper,
didWriteWrapper,
gotErrorWrapper,
c );
bufferevent_settimeout( c->bufev, c->timeout, c->timeout );
bufferevent_enable( c->bufev, EV_READ|EV_WRITE );
bufferevent_setwatermark( c->bufev, EV_READ, 0, TR_RDBUF );
return c;
}
tr_peerIo*
tr_peerIoNewIncoming( struct tr_handle * handle,
const struct in_addr * in_addr,
uint16_t port,
int socket )
{
assert( handle != NULL );
assert( in_addr != NULL );
assert( socket >= 0 );
return tr_peerIoNew( handle, in_addr, port,
NULL, 1,
socket );
}
tr_peerIo*
tr_peerIoNewOutgoing( struct tr_handle * handle,
const struct in_addr * in_addr,
int port,
const uint8_t * torrentHash )
{
int socket;
assert( handle != NULL );
assert( in_addr != NULL );
assert( port >= 0 );
assert( torrentHash != NULL );
socket = tr_netOpenTCP( in_addr, port, 0 );
return socket < 0
? NULL
: tr_peerIoNew( handle, in_addr, port, torrentHash, 0, socket );
}
static void
io_dtor( void * vio )
{
tr_peerIo * io = vio;
bufferevent_free( io->bufev );
tr_netClose( io->socket );
tr_cryptoFree( io->crypto );
tr_free( io );
}
void
tr_peerIoFree( tr_peerIo * io )
{
if( io != NULL )
{
io->canRead = NULL;
io->didWrite = NULL;
io->gotError = NULL;
tr_runInEventThread( io->handle, io_dtor, io );
}
}
tr_handle*
tr_peerIoGetHandle( tr_peerIo * io )
{
assert( io != NULL );
assert( io->handle != NULL );
return io->handle;
}
const struct in_addr*
tr_peerIoGetAddress( const tr_peerIo * io, uint16_t * port )
{
assert( io != NULL );
if( port != NULL )
*port = io->port;
return &io->in_addr;
}
const char*
tr_peerIoAddrStr( const struct in_addr * addr, uint16_t port )
{
static char buf[512];
snprintf( buf, sizeof(buf), "%s:%u", inet_ntoa( *addr ), (unsigned int)port );
return buf;
}
const char*
tr_peerIoGetAddrStr( const tr_peerIo * io )
{
return tr_peerIoAddrStr( &io->in_addr, io->port );
}
void
tr_peerIoTryRead( tr_peerIo * io )
{
if( EVBUFFER_LENGTH( io->bufev->input ) )
canReadWrapper( io->bufev, io );
}
void
tr_peerIoSetIOFuncs( tr_peerIo * io,
tr_can_read_cb readcb,
tr_did_write_cb writecb,
tr_net_error_cb errcb,
void * userData )
{
io->canRead = readcb;
io->didWrite = writecb;
io->gotError = errcb;
io->userData = userData;
tr_peerIoTryRead( io );
}
int
tr_peerIoIsIncoming( const tr_peerIo * c )
{
return c->isIncoming ? 1 : 0;
}
int
tr_peerIoReconnect( tr_peerIo * io )
{
assert( !tr_peerIoIsIncoming( io ) );
if( io->socket >= 0 )
tr_netClose( io->socket );
io->socket = tr_netOpenTCP( &io->in_addr, io->port, 0 );
if( io->socket >= 0 )
{
bufferevent_free( io->bufev );
io->bufev = bufferevent_new( io->socket,
canReadWrapper,
didWriteWrapper,
gotErrorWrapper,
io );
bufferevent_settimeout( io->bufev, io->timeout, io->timeout );
bufferevent_enable( io->bufev, EV_READ|EV_WRITE );
bufferevent_setwatermark( io->bufev, EV_READ, 0, TR_RDBUF );
return 0;
}
return -1;
}
void
tr_peerIoSetTimeoutSecs( tr_peerIo * io, int secs )
{
io->timeout = secs;
bufferevent_settimeout( io->bufev, io->timeout, io->timeout );
}
/**
***
**/
void
tr_peerIoSetTorrentHash( tr_peerIo * io,
const uint8_t * hash )
{
assert( io != NULL );
tr_cryptoSetTorrentHash( io->crypto, hash );
}
const uint8_t*
tr_peerIoGetTorrentHash( tr_peerIo * io )
{
assert( io != NULL );
assert( io->crypto != NULL );
return tr_cryptoGetTorrentHash( io->crypto );
}
int
tr_peerIoHasTorrentHash( const tr_peerIo * io )
{
assert( io != NULL );
assert( io->crypto != NULL );
return tr_cryptoHasTorrentHash( io->crypto );
}
/**
***
**/
void
tr_peerIoSetPeersId( tr_peerIo * io,
const uint8_t * peer_id )
{
assert( io != NULL );
if(( io->peerIdIsSet = peer_id != NULL ))
memcpy( io->peerId, peer_id, 20 );
else
memset( io->peerId, 0, 20 );
}
const uint8_t*
tr_peerIoGetPeersId( const tr_peerIo * io )
{
assert( io != NULL );
assert( io->peerIdIsSet );
return io->peerId;
}
/**
***
**/
void
tr_peerIoEnableLTEP( tr_peerIo * io, int flag )
{
assert( io != NULL );
assert( flag==0 || flag==1 );
io->extensions.extendedProtocolSupported = flag;
}
void
tr_peerIoEnableFEXT( tr_peerIo * io, int flag )
{
assert( io != NULL );
assert( flag==0 || flag==1 );
io->extensions.fastPeersSupported = flag;
}
int
tr_peerIoSupportsLTEP( const tr_peerIo * io )
{
assert( io != NULL );
return io->extensions.extendedProtocolSupported;
}
int
tr_peerIoSupportsFEXT( const tr_peerIo * io )
{
assert( io != NULL );
return io->extensions.fastPeersSupported;
}
/**
***
**/
size_t
tr_peerIoWriteBytesWaiting( const tr_peerIo * io )
{
return EVBUFFER_LENGTH( EVBUFFER_OUTPUT( io->bufev ) );
}
void
tr_peerIoWrite( tr_peerIo * io,
const void * writeme,
int writeme_len )
{
assert( tr_amInEventThread( io->handle ) );
bufferevent_write( io->bufev, writeme, writeme_len );
}
void
tr_peerIoWriteBuf( tr_peerIo * io,
struct evbuffer * buf )
{
const size_t n = EVBUFFER_LENGTH( buf );
tr_peerIoWrite( io, EVBUFFER_DATA(buf), n );
evbuffer_drain( buf, n );
}
/**
***
**/
tr_crypto*
tr_peerIoGetCrypto( tr_peerIo * c )
{
return c->crypto;
}
void
tr_peerIoSetEncryption( tr_peerIo * io,
int encryptionMode )
{
assert( io != NULL );
assert( encryptionMode==PEER_ENCRYPTION_NONE || encryptionMode==PEER_ENCRYPTION_RC4 );
io->encryptionMode = encryptionMode;
}
int
tr_peerIoIsEncrypted( const tr_peerIo * io )
{
return io!=NULL && io->encryptionMode==PEER_ENCRYPTION_RC4;
}
/**
***
**/
void
tr_peerIoWriteBytes( tr_peerIo * io,
struct evbuffer * outbuf,
const void * bytes,
size_t byteCount )
{
uint8_t * tmp;
switch( io->encryptionMode )
{
case PEER_ENCRYPTION_NONE:
evbuffer_add( outbuf, bytes, byteCount );
break;
case PEER_ENCRYPTION_RC4:
tmp = tr_new( uint8_t, byteCount );
tr_cryptoEncrypt( io->crypto, byteCount, bytes, tmp );
evbuffer_add( outbuf, tmp, byteCount );
tr_free( tmp );
break;
default:
assert( 0 );
}
}
void
tr_peerIoWriteUint8( tr_peerIo * io,
struct evbuffer * outbuf,
uint8_t writeme )
{
tr_peerIoWriteBytes( io, outbuf, &writeme, sizeof(uint8_t) );
}
void
tr_peerIoWriteUint16( tr_peerIo * io,
struct evbuffer * outbuf,
uint16_t writeme )
{
uint16_t tmp = htons( writeme );
tr_peerIoWriteBytes( io, outbuf, &tmp, sizeof(uint16_t) );
}
void
tr_peerIoWriteUint32( tr_peerIo * io,
struct evbuffer * outbuf,
uint32_t writeme )
{
uint32_t tmp = htonl( writeme );
tr_peerIoWriteBytes( io, outbuf, &tmp, sizeof(uint32_t) );
}
/***
****
***/
void
tr_peerIoReadBytes( tr_peerIo * io,
struct evbuffer * inbuf,
void * bytes,
size_t byteCount )
{
assert( EVBUFFER_LENGTH( inbuf ) >= byteCount );
switch( io->encryptionMode )
{
case PEER_ENCRYPTION_NONE:
evbuffer_remove( inbuf, bytes, byteCount );
break;
case PEER_ENCRYPTION_RC4:
evbuffer_remove( inbuf, bytes, byteCount );
tr_cryptoDecrypt( io->crypto, byteCount, bytes, bytes );
break;
default:
assert( 0 );
}
}
void
tr_peerIoReadUint8( tr_peerIo * io,
struct evbuffer * inbuf,
uint8_t * setme )
{
tr_peerIoReadBytes( io, inbuf, setme, sizeof(uint8_t) );
}
void
tr_peerIoReadUint16( tr_peerIo * io,
struct evbuffer * inbuf,
uint16_t * setme )
{
uint16_t tmp;
tr_peerIoReadBytes( io, inbuf, &tmp, sizeof(uint16_t) );
*setme = ntohs( tmp );
}
void
tr_peerIoReadUint32( tr_peerIo * io,
struct evbuffer * inbuf,
uint32_t * setme )
{
uint32_t tmp;
tr_peerIoReadBytes( io, inbuf, &tmp, sizeof(uint32_t) );
*setme = ntohl( tmp );
}
void
tr_peerIoDrain( tr_peerIo * io,
struct evbuffer * inbuf,
size_t byteCount )
{
uint8_t * tmp = tr_new( uint8_t, byteCount );
tr_peerIoReadBytes( io, inbuf, tmp, byteCount );
tr_free( tmp );
}