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Fix encoding of peer count in proxy sync packet

master
Dirk Engling 11 years ago
parent
commit
1f17fe9d3b
  1. 122
      proxy.c

122
proxy.c

@ -1,7 +1,7 @@
/* This software was written by Dirk Engling <erdgeist@erdgeist.org>
It is considered beerware. Prost. Skol. Cheers or whatever.
$Id: proxy.c,v 1.9 2010/08/13 12:47:15 erdgeist Exp $ */
$Id: proxy.c,v 1.10 2010/08/14 10:56:14 erdgeist Exp $ */
/* System */
#include <stdint.h>
@ -368,7 +368,7 @@ static void handle_read( int64 peersocket ) {
/* See, if we already have a connection to that peer */
for( i=0; i<MAX_PEERS; ++i )
if( ( g_connections[i].state & FLAG_MASK ) == FLAG_CONNECTED &&
if( ( g_connections[i].state & FLAG_MASK ) == FLAG_CONNECTED &&
g_connections[i].tracker_id == tracker_id ) {
fprintf( stderr, "Peer already connected. Closing connection.\n" );
goto close_socket;
@ -557,8 +557,8 @@ int main( int argc, char **argv ) {
ot_try_bind( serverip, tmpport );
++sbound;
break;
case 'c':
if( g_connection_count > MAX_PEERS / 2 ) exerr( "Connection limit exceeded.\n" );
case 'c':
if( g_connection_count > MAX_PEERS / 2 ) exerr( "Connection limit exceeded.\n" );
tmpport = 0;
if( !scan_ip6_port( optarg,
g_connections[g_connection_count].ip,
@ -613,46 +613,42 @@ static void * streamsync_worker( void * args ) {
}
/* Maximal memory requirement: max 3 blocks, max torrents * 20 + max peers * 7 */
mem = 3 * ( 4 + 1 + 1 + 2 ) + ( count_one + count_two ) * 19 + count_def * 20 +
mem = 3 * ( 4 + 1 + 1 + 2 ) + ( count_one + count_two ) * 19 + count_def * ( 19 + 6 ) +
( count_one + 2 * count_two + count_peers ) * 7;
fprintf( stderr, "Mem: %zd\n", mem );
fprintf( stderr, "Mem: %zd\n", mem );
ptr = ptr_a = ptr_b = ptr_c = malloc( mem );
if( !ptr ) goto unlock_continue;
if( count_one > 8 ) {
if( count_one > 8 || !count_def ) {
mem_a = 4 + 1 + 1 + 2 + count_one * ( 19 + 7 );
ptr_b += mem_a; ptr_c += mem_a;
memcpy( ptr_a, &g_tracker_id, sizeof(g_tracker_id)); /* Offset 0: the tracker ID */
ptr_a[4] = 1; /* Offset 4: packet type 1 */
ptr_a[5] = (bucket << 8) >> OT_BUCKET_COUNT_BITS; /* Offset 5: the shared prefix */
ptr_a[4] = 1; /* Offset 4: packet type 1 */
ptr_a[5] = (bucket << 8) >> OT_BUCKET_COUNT_BITS; /* Offset 5: the shared prefix */
ptr_a[6] = count_one >> 8;
ptr_a[7] = count_one & 255;
ptr_a += 8;
} else {
} else
count_def += count_one;
count_peers += count_one;
}
if( count_two > 8 ) {
if( count_two > 8 || !count_def ) {
mem_b = 4 + 1 + 1 + 2 + count_two * ( 19 + 14 );
ptr_c += mem_b;
memcpy( ptr_b, &g_tracker_id, sizeof(g_tracker_id)); /* Offset 0: the tracker ID */
ptr_b[4] = 2; /* Offset 4: packet type 2 */
ptr_b[5] = (bucket << 8) >> OT_BUCKET_COUNT_BITS; /* Offset 5: the shared prefix */
ptr_b[4] = 2; /* Offset 4: packet type 2 */
ptr_b[5] = (bucket << 8) >> OT_BUCKET_COUNT_BITS; /* Offset 5: the shared prefix */
ptr_b[6] = count_two >> 8;
ptr_b[7] = count_two & 255;
ptr_b += 8;
} else {
} else
count_def += count_two;
count_peers += 2 * count_two;
}
if( count_def ) {
memcpy( ptr_c, &g_tracker_id, sizeof(g_tracker_id)); /* Offset 0: the tracker ID */
ptr_c[4] = 0; /* Offset 4: packet type 0 */
ptr_c[5] = (bucket << 8) >> OT_BUCKET_COUNT_BITS; /* Offset 5: the shared prefix */
ptr_c[4] = 0; /* Offset 4: packet type 0 */
ptr_c[5] = (bucket << 8) >> OT_BUCKET_COUNT_BITS; /* Offset 5: the shared prefix */
ptr_c[6] = count_def >> 8;
ptr_c[7] = count_def & 255;
ptr_c += 8;
@ -665,26 +661,36 @@ static void * streamsync_worker( void * args ) {
ot_peerlist *peer_list = torrent->peer_list;
ot_peer *peers = (ot_peer*)(peer_list->peers.data);
uint8_t **dst;
int multi = 0;
switch( peer_list->peer_count ) {
/* Determine destination slot */
count_peers = peer_list->peer_count;
switch( count_peers ) {
case 0: continue;
case 1: dst = mem_a ? &ptr_a : &ptr_c; break;
case 2: dst = mem_b ? &ptr_b : &ptr_c; break;
default: dst = &ptr_c; multi = 1; break;
default: dst = &ptr_c; break;
}
do {
size_t i, pc = peer_list->peer_count;
if( pc > 255 ) pc = 255;
memcpy( *dst, torrent->hash + 1, sizeof( ot_hash ) - 1);
*dst += sizeof( ot_hash ) - 1;
if( multi ) *(*dst)++ = pc;
for( i=0; i < pc; ++i ) {
memcpy( *dst, peers++, OT_IP_SIZE + 3 );
*dst += OT_IP_SIZE + 3;
/* Copy tail of info_hash, advance pointer */
memcpy( *dst, torrent->hash + 1, sizeof( ot_hash ) - 1);
*dst += sizeof( ot_hash ) - 1;
/* Encode peer count */
if( dst == &ptr_c )
while( count_peers ) {
if( count_peers <= 0x7f )
*(*dst)++ = count_peers;
else
*(*dst)++ = 0x80 | ( count_peers & 0x7f );
count_peers >>= 7;
}
peer_list->peer_count -= pc;
} while( peer_list->peer_count );
/* Copy peers */
count_peers = peer_list->peer_count;
while( count_peers-- ) {
memcpy( *dst, peers++, OT_IP_SIZE + 3 );
*dst += OT_IP_SIZE + 3;
}
free_peerlist(peer_list);
}
@ -700,7 +706,7 @@ unlock_continue:
if( ptr_a > ptr_c ) ptr_c = ptr_a;
mem = ptr_c - ptr;
for( i=0; i<g_connection_count; ++i ) {
for( i=0; i < g_connection_count; ++i ) {
if( PROXYPEER_ISCONNECTED(g_connections[i].state) ) {
void *tmp = malloc( mem );
if( tmp ) {
@ -735,18 +741,30 @@ void livesync_ticker( ) {
}
static void livesync_proxytell( uint8_t prefix, uint8_t *info_hash, uint8_t *peer ) {
unsigned int i;
*g_peerbuffer_pos = prefix;
memcpy( g_peerbuffer_pos + 1, info_hash, sizeof(ot_hash) - 1 );
memcpy( g_peerbuffer_pos + sizeof(ot_hash), peer, sizeof(ot_peer) - 1 );
g_peerbuffer_pos += sizeof(ot_hash) + sizeof(ot_peer);
/* Dump info_hash */
for( i=0; i<sizeof(ot_hash); ++i )
printf( "%02X", g_peerbuffer_pos[i] );
putchar( ':' );
g_peerbuffer_pos += sizeof(ot_hash);
printf( "%d.%d.%d.%d:%hd (%02X %02X)\n", g_peerbuffer_pos[0], g_peerbuffer_pos[1], g_peerbuffer_pos[2], g_peerbuffer_pos[3],
g_peerbuffer_pos[4] | ( g_peerbuffer_pos[5] << 8 ), g_peerbuffer_pos[6], g_peerbuffer_pos[7] );
g_peerbuffer_pos += sizeof(ot_peer);
if( g_peerbuffer_pos >= g_peerbuffer_highwater )
livesync_issue_peersync();
}
static void process_indata( proxy_peer * peer ) {
int ensuremem, consumed, peers;
int consumed, peers;
uint8_t *data = peer->indata, *hash;
uint8_t *dataend = data + peer->indata_length;
@ -760,21 +778,37 @@ static void process_indata( proxy_peer * peer ) {
peer->packet_tprefix = data[5];
peer->packet_tcount = data[6] * 256 + data[7];
data += 8;
printf( "type: %d, prefix: %02X, torrentcount: %d\n", peer->packet_type, peer->packet_tprefix, peer->packet_tcount );
}
/* ensure size for the complete torrent block */
if( data + 26 > dataend ) break;
peers = peer->packet_type ? peer->packet_type : data[19];
ensuremem = 19 + ( peer->packet_type == 0 ) + 7 * peers;
if( data + ensuremem > dataend ) break;
next_torrent:
/* Ensure size for the complete torrent block */
if( data + sizeof(ot_hash) + OT_IP_SIZE + 3 > dataend ) break;
/* Advance pointer to peer count or peers */
hash = data;
data += 19 + ( peer->packet_type == 0 );
data += sizeof(ot_hash) - 1;
/* Type 0 has peer count encoded before each peers */
if( peer->packet_type == 0 ) {
int shift = 0;
peers = 0;
do peers |= ( 0x7f & *data ) << ( 7 * shift );
while ( *(data++) & 0x80 && shift++ < 6 );
} else
peers = peer->packet_type;
/* Ensure enough data being read to hold all peers */
if( data + 7 * peers > dataend ) break;
printf( "peers: %d\n", peers );
while( peers-- ) {
livesync_proxytell( peer->packet_tprefix, hash, data );
data += 7;
data += OT_IP_SIZE + 3;
}
if( --peer->packet_tcount )
goto next_torrent;
}
consumed = data - peer->indata;

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