transmission/libtransmission/net.c

438 lines
12 KiB
C

/******************************************************************************
* $Id$
*
* 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 <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <fcntl.h>
#include "transmission.h"
#include "fdlimit.h"
#include "net.h"
/***********************************************************************
* DNS resolution
**********************************************************************/
/***********************************************************************
* tr_netResolve
***********************************************************************
* Synchronous "resolution": only works with character strings
* representing numbers expressed in the Internet standard `.' notation.
* Returns a non-zero value if an error occurs.
**********************************************************************/
int tr_netResolve( const char * address, struct in_addr * addr )
{
addr->s_addr = inet_addr( address );
return ( addr->s_addr == 0xFFFFFFFF );
}
static tr_thread_t resolveThread;
static tr_lock_t resolveLock;
static tr_cond_t resolveCond;
static volatile int resolveDie;
static tr_resolve_t * resolveQueue;
static void resolveRelease ( tr_resolve_t * );
static void resolveFunc ( void * );
struct tr_resolve_s
{
tr_tristate_t status;
char * address;
struct in_addr addr;
int refcount;
tr_resolve_t * next;
};
/***********************************************************************
* tr_netResolveThreadInit
***********************************************************************
* Initializes the static variables used for resolution and launch the
* gethostbyname thread.
**********************************************************************/
void tr_netResolveThreadInit()
{
resolveDie = 0;
resolveQueue = NULL;
tr_lockInit( &resolveLock );
tr_condInit( &resolveCond );
tr_threadCreate( &resolveThread, resolveFunc, NULL, "resolve" );
}
/***********************************************************************
* tr_netResolveThreadClose
***********************************************************************
* Notices the gethostbyname thread that is should terminate. Doesn't
* wait until it does, in case it is stuck in a resolution: we let it
* die and clean itself up.
**********************************************************************/
void tr_netResolveThreadClose()
{
tr_lockLock( &resolveLock );
resolveDie = 1;
tr_lockUnlock( &resolveLock );
tr_condSignal( &resolveCond );
tr_wait( 200 );
}
/***********************************************************************
* tr_netResolveInit
***********************************************************************
* Adds an address to the resolution queue.
**********************************************************************/
tr_resolve_t * tr_netResolveInit( const char * address )
{
tr_resolve_t * r;
r = malloc( sizeof( tr_resolve_t ) );
r->status = TR_NET_WAIT;
r->address = strdup( address );
r->refcount = 2;
r->next = NULL;
tr_lockLock( &resolveLock );
if( !resolveQueue )
{
resolveQueue = r;
}
else
{
tr_resolve_t * iter;
for( iter = resolveQueue; iter->next; iter = iter->next );
iter->next = r;
}
tr_lockUnlock( &resolveLock );
tr_condSignal( &resolveCond );
return r;
}
/***********************************************************************
* tr_netResolvePulse
***********************************************************************
* Checks the current status of a resolution.
**********************************************************************/
tr_tristate_t tr_netResolvePulse( tr_resolve_t * r, struct in_addr * addr )
{
tr_tristate_t ret;
tr_lockLock( &resolveLock );
ret = r->status;
if( ret == TR_NET_OK )
{
*addr = r->addr;
}
tr_lockUnlock( &resolveLock );
return ret;
}
/***********************************************************************
* tr_netResolveClose
***********************************************************************
*
**********************************************************************/
void tr_netResolveClose( tr_resolve_t * r )
{
resolveRelease( r );
}
/***********************************************************************
* resolveRelease
***********************************************************************
* The allocated tr_resolve_t structures should be freed when
* tr_netResolveClose was called *and* it was removed from the queue.
* This can happen in any order, so we use a refcount to know we can
* take it out.
**********************************************************************/
static void resolveRelease( tr_resolve_t * r )
{
if( --r->refcount < 1 )
{
free( r->address );
free( r );
}
}
/***********************************************************************
* resolveFunc
***********************************************************************
* Keeps waiting for addresses to resolve, and removes them from the
* queue once resolution is done.
**********************************************************************/
static void resolveFunc( void * arg UNUSED )
{
tr_resolve_t * r;
struct hostent * host;
tr_lockLock( &resolveLock );
while( !resolveDie )
{
if( !( r = resolveQueue ) )
{
tr_condWait( &resolveCond, &resolveLock );
continue;
}
/* Blocking resolution */
tr_lockUnlock( &resolveLock );
host = gethostbyname( r->address );
tr_lockLock( &resolveLock );
if( host )
{
memcpy( &r->addr, host->h_addr, host->h_length );
r->status = TR_NET_OK;
}
else
{
r->status = TR_NET_ERROR;
}
resolveQueue = r->next;
resolveRelease( r );
}
/* Clean up */
tr_lockUnlock( &resolveLock );
tr_lockClose( &resolveLock );
while( ( r = resolveQueue ) )
{
resolveQueue = r->next;
resolveRelease( r );
}
}
/***********************************************************************
* TCP/UDP sockets
**********************************************************************/
static int makeSocketNonBlocking( int s )
{
int flags;
#ifdef SYS_BEOS
flags = 1;
if( setsockopt( s, SOL_SOCKET, SO_NONBLOCK,
&flags, sizeof( int ) ) < 0 )
#else
if( ( flags = fcntl( s, F_GETFL, 0 ) ) < 0 ||
fcntl( s, F_SETFL, flags | O_NONBLOCK ) < 0 )
#endif
{
tr_err( "Could not set socket to non-blocking mode (%s)",
strerror( errno ) );
tr_netClose( s );
return -1;
}
return s;
}
static int createSocket( int type, int priority )
{
int s;
if( ( s = tr_fdSocketCreate( type, priority ) ) < 0 )
{
return -1;
}
return makeSocketNonBlocking( s );
}
int tr_netOpen( const struct in_addr * addr, in_port_t port,
int type, int priority )
{
int s;
struct sockaddr_in sock;
if( ( s = createSocket( type, priority ) ) < 0 )
{
return -1;
}
memset( &sock, 0, sizeof( sock ) );
sock.sin_family = AF_INET;
sock.sin_addr.s_addr = addr->s_addr;
sock.sin_port = port;
if( connect( s, (struct sockaddr *) &sock,
sizeof( struct sockaddr_in ) ) < 0 &&
errno != EINPROGRESS )
{
tr_err( "Could not connect socket (%s)", strerror( errno ) );
tr_netClose( s );
return -1;
}
return s;
}
#ifdef IP_ADD_MEMBERSHIP
int tr_netMcastOpen( int port, const struct in_addr * addr )
{
int fd;
struct ip_mreq req;
fd = tr_netBindUDP( port );
if( 0 > fd )
{
return -1;
}
memset( &req, 0, sizeof( req ) );
req.imr_multiaddr.s_addr = addr->s_addr;
req.imr_interface.s_addr = htonl( INADDR_ANY );
if( setsockopt( fd, IPPROTO_IP, IP_ADD_MEMBERSHIP, &req, sizeof ( req ) ) )
{
tr_err( "Could not join multicast group (%s)", strerror( errno ) );
tr_netClose( fd );
return -1;
}
return fd;
}
#else /* IP_ADD_MEMBERSHIP */
int tr_netMcastOpen( int port UNUSED, const struct in_addr * addr UNUSED )
{
return -1;
}
#endif /* IP_ADD_MEMBERSHIP */
int tr_netBind( int port, int type )
{
int s;
struct sockaddr_in sock;
#if defined( SO_REUSEADDR ) || defined( SO_REUSEPORT )
int optval;
#endif
if( ( s = createSocket( type, 1 ) ) < 0 )
{
return -1;
}
#ifdef SO_REUSEADDR
optval = 1;
setsockopt( s, SOL_SOCKET, SO_REUSEADDR, &optval, sizeof( optval ) );
#endif
#ifdef SO_REUSEPORT
if( SOCK_DGRAM == type )
{
optval = 1;
setsockopt( s, SOL_SOCKET, SO_REUSEPORT, &optval, sizeof( optval ) );
}
#endif
memset( &sock, 0, sizeof( sock ) );
sock.sin_family = AF_INET;
sock.sin_addr.s_addr = INADDR_ANY;
sock.sin_port = htons( port );
if( bind( s, (struct sockaddr *) &sock,
sizeof( struct sockaddr_in ) ) )
{
tr_err( "Could not bind port %d", port );
tr_netClose( s );
return -1;
}
return s;
}
int tr_netAccept( int b, struct in_addr * addr, in_port_t * port )
{
int s;
if( ( s = tr_fdSocketAccept( b, addr, port ) ) < 0 )
{
return -1;
}
return makeSocketNonBlocking( s );
}
int
tr_netSend( int s, const void * buf, int size )
{
const int ret = send( s, buf, size, 0 );
if( ret >= 0 )
return ret;
if( errno == ENOTCONN || errno == EAGAIN || errno == EWOULDBLOCK )
return TR_NET_BLOCK;
return TR_NET_CLOSE;
}
int tr_netRecvFrom( int s, uint8_t * buf, int size, struct sockaddr_in * addr )
{
socklen_t len;
int ret;
len = ( NULL == addr ? 0 : sizeof( *addr ) );
ret = recvfrom( s, buf, size, 0, ( struct sockaddr * ) addr, &len );
if( ret < 0 )
{
if( errno == EAGAIN || errno == EWOULDBLOCK )
{
ret = TR_NET_BLOCK;
}
else
{
ret = TR_NET_CLOSE;
}
}
if( !ret )
{
ret = TR_NET_CLOSE;
}
return ret;
}
void tr_netClose( int s )
{
tr_fdSocketClose( s );
}
void tr_netNtop( const struct in_addr * addr, char * buf, int len )
{
const uint8_t * cast;
cast = (const uint8_t *)addr;
snprintf( buf, len, "%hhu.%hhu.%hhu.%hhu",
cast[0], cast[1], cast[2], cast[3] );
}