310 lines
8.7 KiB
C
310 lines
8.7 KiB
C
/******************************************************************************
|
|
* $Id$
|
|
*
|
|
* Copyright (c) 2006-2007 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.
|
|
*****************************************************************************/
|
|
|
|
#define EXTENDED_HANDSHAKE_ID 0
|
|
#define EXTENDED_PEX_ID 1
|
|
|
|
static char *
|
|
makeCommonPex( tr_torrent_t * tor, tr_peer_t * peer, int * len,
|
|
int ( *peerfunc )( tr_peertree_t *, benc_val_t * ),
|
|
const char * extrakey, benc_val_t * extraval )
|
|
{
|
|
tr_peertree_t * sent, added, common;
|
|
int ii;
|
|
tr_peer_t * pp;
|
|
tr_peertree_entry_t * found;
|
|
benc_val_t val, * addval, * delval, * extra;
|
|
char * buf;
|
|
|
|
*len = 0;
|
|
sent = &peer->sentPeers;
|
|
peertreeInit( &added );
|
|
peertreeInit( &common );
|
|
|
|
/* build trees of peers added and deleted since the last pex */
|
|
for( ii = 0; ii < tor->peerCount; ii++ )
|
|
{
|
|
pp = tor->peers[ii];
|
|
if( 0 == pp->port || 0 == tr_addrcmp( &peer->addr, &pp->addr ) )
|
|
{
|
|
continue;
|
|
}
|
|
found = peertreeGet( sent, &pp->addr, pp->port );
|
|
if( NULL != found )
|
|
{
|
|
peertreeMove( &common, sent, found );
|
|
}
|
|
else if( NULL == peertreeAdd( &added, &pp->addr, pp->port ) )
|
|
{
|
|
peertreeMerge( sent, &common );
|
|
peertreeFree( &added );
|
|
tr_bencFree( extraval );
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
/* build the dictionaries */
|
|
tr_bencInit( &val, TYPE_DICT );
|
|
if( ( peertreeEmpty( &added ) && peertreeEmpty( sent ) ) ||
|
|
tr_bencDictReserve( &val, 3 ) )
|
|
{
|
|
tr_bencFree( &val );
|
|
peertreeMerge( sent, &common );
|
|
peertreeFree( &added );
|
|
tr_bencFree( extraval );
|
|
return NULL;
|
|
}
|
|
extra = tr_bencDictAdd( &val, extrakey );
|
|
addval = tr_bencDictAdd( &val, "added" );
|
|
delval = tr_bencDictAdd( &val, "dropped" );
|
|
assert( NULL != extra && NULL != addval && NULL != delval );
|
|
if( (*peerfunc)( &added, addval ) || (*peerfunc)( sent, delval ) )
|
|
{
|
|
tr_bencFree( &val );
|
|
peertreeMerge( sent, &common );
|
|
peertreeFree( &added );
|
|
tr_bencFree( extraval );
|
|
return NULL;
|
|
}
|
|
*extra = *extraval;
|
|
memset( extraval, 0, sizeof( extraval ) );
|
|
|
|
/* bencode it */
|
|
buf = tr_bencSaveMalloc( &val, len );
|
|
tr_bencFree( &val );
|
|
if( NULL == buf )
|
|
{
|
|
peertreeMerge( sent, &common );
|
|
peertreeFree( &added );
|
|
return NULL;
|
|
}
|
|
|
|
peertreeSwap( sent, &common );
|
|
peertreeMerge( sent, &added );
|
|
peertreeFree( &common );
|
|
|
|
return buf;
|
|
}
|
|
|
|
static char *
|
|
makeExtendedHandshake( tr_torrent_t * tor, tr_peer_t * peer, int * len )
|
|
{
|
|
benc_val_t val, * msgsval;
|
|
char * buf, * vers;
|
|
|
|
/* get human-readable version string */
|
|
vers = NULL;
|
|
asprintf( &vers, "%s %s", TR_NAME, VERSION_STRING );
|
|
if( NULL == vers )
|
|
{
|
|
return NULL;
|
|
}
|
|
|
|
/* reserve space in toplevel dictionary for v, m, and possibly p */
|
|
tr_bencInit( &val, TYPE_DICT );
|
|
if( tr_bencDictReserve( &val, ( 0 < tor->publicPort ? 3 : 2 ) ) )
|
|
{
|
|
free( vers );
|
|
tr_bencFree( &val );
|
|
return NULL;
|
|
}
|
|
|
|
/* human readable version string */
|
|
tr_bencInitStr( tr_bencDictAdd( &val, "v" ), vers, 0, 0 );
|
|
|
|
/* create dict of supported extended messages */
|
|
msgsval = tr_bencDictAdd( &val, "m" );
|
|
tr_bencInit( msgsval, TYPE_DICT );
|
|
if( tr_bencDictReserve( msgsval, 1 ) )
|
|
{
|
|
tr_bencFree( &val );
|
|
return NULL;
|
|
}
|
|
/* for public torrents advertise utorrent pex message */
|
|
tr_bencInitInt( tr_bencDictAdd( msgsval, "ut_pex" ),
|
|
( peer->private ? 0 : EXTENDED_PEX_ID ) );
|
|
|
|
/* our listening port */
|
|
if( 0 < tor->publicPort )
|
|
{
|
|
tr_bencInitInt( tr_bencDictAdd( &val, "p" ), tor->publicPort );
|
|
}
|
|
|
|
/* bencode it */
|
|
buf = tr_bencSaveMalloc( &val, len );
|
|
tr_bencFree( &val );
|
|
if( NULL == buf )
|
|
{
|
|
return NULL;
|
|
}
|
|
|
|
peer->advertisedPort = tor->publicPort;
|
|
|
|
peer_dbg( "SEND extended-handshake, %s pex",
|
|
( peer->private ? "without" : "with" ) );
|
|
|
|
return buf;
|
|
}
|
|
|
|
static int
|
|
peertreeToBencUT( tr_peertree_t * tree, benc_val_t * val )
|
|
{
|
|
char * buf;
|
|
tr_peertree_entry_t * ii;
|
|
int count;
|
|
|
|
count = peertreeCount( tree );
|
|
if( 0 == count )
|
|
{
|
|
tr_bencInitStr( val, NULL, 0, 1 );
|
|
return 0;
|
|
}
|
|
|
|
buf = malloc( 6 * count );
|
|
if( NULL == buf )
|
|
{
|
|
return 1;
|
|
}
|
|
tr_bencInitStr( val, buf, 6 * count, 0 );
|
|
|
|
for( ii = peertreeFirst( tree ); NULL != ii;
|
|
ii = peertreeNext( tree, ii ) )
|
|
{
|
|
assert( 0 < count );
|
|
count--;
|
|
memcpy( buf + 6 * count, ii->peer, 6 );
|
|
}
|
|
assert( 0 == count );
|
|
|
|
return 0;
|
|
}
|
|
|
|
static char *
|
|
makeUTPex( tr_torrent_t * tor, tr_peer_t * peer, int * len )
|
|
{
|
|
benc_val_t val;
|
|
char * ret;
|
|
|
|
peer_dbg( "SEND extended-pex" );
|
|
|
|
assert( !peer->private );
|
|
tr_bencInitStr( &val, NULL, 0, 1 );
|
|
ret = makeCommonPex( tor, peer, len, peertreeToBencUT, "added.f", &val );
|
|
|
|
return ret;
|
|
}
|
|
|
|
static inline int
|
|
parseExtendedHandshake( tr_peer_t * peer, uint8_t * buf, int len )
|
|
{
|
|
benc_val_t val, * sub;
|
|
int dbgport, dbgpex;
|
|
|
|
if( tr_bencLoad( buf, len, &val, NULL ) )
|
|
{
|
|
peer_dbg( "GET extended-handshake, invalid bencoding" );
|
|
return TR_ERROR;
|
|
}
|
|
if( TYPE_DICT != val.type )
|
|
{
|
|
peer_dbg( "GET extended-handshake, not a dictionary" );
|
|
tr_bencFree( &val );
|
|
return TR_ERROR;
|
|
}
|
|
|
|
/* check supported messages for utorrent pex */
|
|
sub = tr_bencDictFind( &val, "m" );
|
|
dbgpex = -1;
|
|
if( NULL != sub && TYPE_DICT == sub->type )
|
|
{
|
|
sub = tr_bencDictFind( sub, "ut_pex" );
|
|
if( NULL != sub && TYPE_INT == sub->type )
|
|
{
|
|
peer->pexStatus = 0;
|
|
if( 0x0 < sub->val.i && 0xff >= sub->val.i )
|
|
{
|
|
peer->pexStatus = sub->val.i;
|
|
dbgpex = sub->val.i;
|
|
}
|
|
}
|
|
}
|
|
|
|
/* get peer's listening port */
|
|
sub = tr_bencDictFind( &val, "p" );
|
|
dbgport = -1;
|
|
if( NULL != sub && TYPE_INT == sub->type &&
|
|
0x0 < sub->val.i && 0xffff >= sub->val.i )
|
|
{
|
|
peer->port = htons( (uint16_t) sub->val.i );
|
|
dbgport = sub->val.i;
|
|
}
|
|
|
|
peer_dbg( "GET extended-handshake, ok port=%i pex=%i", dbgport, dbgpex );
|
|
|
|
tr_bencFree( &val );
|
|
return TR_OK;
|
|
}
|
|
|
|
static inline int
|
|
parseUTPex( tr_torrent_t * tor, tr_peer_t * peer, uint8_t * buf, int len )
|
|
{
|
|
benc_val_t val, * sub;
|
|
int used;
|
|
|
|
if( peer->private || PEX_PEER_CUTOFF <= tor->peerCount )
|
|
{
|
|
peer_dbg( "GET extended-pex, ignoring p=%i c=(%i<=%i)",
|
|
peer->private, PEX_PEER_CUTOFF, tor->peerCount );
|
|
return TR_OK;
|
|
}
|
|
|
|
if( tr_bencLoad( buf, len, &val, NULL ) )
|
|
{
|
|
peer_dbg( "GET extended-pex, invalid bencoding" );
|
|
return TR_ERROR;
|
|
}
|
|
if( TYPE_DICT != val.type )
|
|
{
|
|
tr_bencFree( &val );
|
|
peer_dbg( "GET extended-pex, not a dictionary" );
|
|
return TR_ERROR;
|
|
}
|
|
|
|
sub = tr_bencDictFind( &val, "added" );
|
|
if( NULL != sub && TYPE_STR == sub->type && 0 == sub->val.s.i % 6 )
|
|
{
|
|
used = tr_torrentAddCompact( tor, TR_PEER_FROM_PEX,
|
|
( uint8_t * )sub->val.s.s,
|
|
sub->val.s.i / 6 );
|
|
peer_dbg( "GET extended-pex, got %i peers, used %i",
|
|
sub->val.s.i / 6, used );
|
|
}
|
|
else
|
|
{
|
|
peer_dbg( "GET extended-pex, no peers" );
|
|
}
|
|
|
|
return TR_OK;
|
|
}
|