/*
* Copyright (c) 2008-2024 Jonathan Schleifer <js@nil.im>
*
* All rights reserved.
*
* This program is free software: you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License version 3.0 only,
* as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
* version 3.0 for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* version 3.0 along with this program. If not, see
* <https://www.gnu.org/licenses/>.
*/
#include "config.h"
#include <errno.h>
#import "OFTCPSocketSOCKS5Connector.h"
#import "OFData.h"
#import "OFRunLoop.h"
#import "OFString.h"
#import "OFConnectIPSocketFailedException.h"
enum {
stateSendAuthentication = 1,
stateReadVersion,
stateSendRequest,
stateReadResponse,
stateReadAddress,
stateReadAddressLength,
};
@implementation OFTCPSocketSOCKS5Connector
- (instancetype)initWithSocket: (OFTCPSocket *)sock
host: (OFString *)host
port: (uint16_t)port
delegate: (id <OFTCPSocketDelegate>)delegate
#ifdef OF_HAVE_BLOCKS
block: (OFTCPSocketAsyncConnectBlock)block
#endif
{
self = [super init];
@try {
_socket = [sock retain];
_host = [host copy];
_port = port;
_delegate = [delegate retain];
#ifdef OF_HAVE_BLOCKS
_block = [block copy];
#endif
_socket.delegate = self;
} @catch (id e) {
[self release];
@throw e;
}
return self;
}
- (void)dealloc
{
if (_socket.delegate == self)
_socket.delegate = _delegate;
[_socket release];
[_host release];
[_delegate release];
#ifdef OF_HAVE_BLOCKS
[_block release];
#endif
[_exception release];
[_request release];
[super dealloc];
}
- (void)didConnect
{
_socket.delegate = _delegate;
#ifdef OF_HAVE_BLOCKS
if (_block != NULL)
_block(_exception);
else {
#endif
if ([_delegate respondsToSelector:
@selector(socket:didConnectToHost:port:exception:)])
[_delegate socket: _socket
didConnectToHost: _host
port: _port
exception: _exception];
#ifdef OF_HAVE_BLOCKS
}
#endif
}
- (void)socket: (OFTCPSocket *)sock
didConnectToHost: (OFString *)host
port: (uint16_t)port
exception: (id)exception
{
OFData *data;
if (exception != nil) {
_exception = [exception retain];
[self didConnect];
return;
}
data = [OFData dataWithItems: "\x05\x01\x00" count: 3];
_SOCKS5State = stateSendAuthentication;
[_socket asyncWriteData: data
runLoopMode: [OFRunLoop currentRunLoop].currentMode];
}
- (bool)stream: (OFStream *)sock
didReadIntoBuffer: (void *)buffer
length: (size_t)length
exception: (id)exception
{
OFRunLoopMode runLoopMode;
unsigned char *SOCKSVersion;
uint8_t hostLength;
unsigned char port[2];
unsigned char *response, *addressLength;
if (exception != nil) {
_exception = [exception retain];
[self didConnect];
return false;
}
runLoopMode = [OFRunLoop currentRunLoop].currentMode;
switch (_SOCKS5State) {
case stateReadVersion:
SOCKSVersion = buffer;
if (SOCKSVersion[0] != 5 || SOCKSVersion[1] != 0) {
_exception = [[OFConnectIPSocketFailedException alloc]
initWithHost: _host
port: _port
socket: self
errNo: EPROTONOSUPPORT];
[self didConnect];
return false;
}
[_request release];
_request = [[OFMutableData alloc] init];
[_request addItems: "\x05\x01\x00\x03" count: 4];
hostLength = (uint8_t)_host.UTF8StringLength;
[_request addItem: &hostLength];
[_request addItems: _host.UTF8String count: hostLength];
port[0] = _port >> 8;
port[1] = _port & 0xFF;
[_request addItems: port count: 2];
_SOCKS5State = stateSendRequest;
[_socket asyncWriteData: _request runLoopMode: runLoopMode];
return false;
case stateReadResponse:
response = buffer;
if (response[0] != 5 || response[2] != 0) {
_exception = [[OFConnectIPSocketFailedException alloc]
initWithHost: _host
port: _port
socket: self
errNo: EPROTONOSUPPORT];
[self didConnect];
return false;
}
if (response[1] != 0) {
int errNo;
switch (response[1]) {
case 0x02:
errNo = EPERM;
break;
case 0x03:
errNo = ENETUNREACH;
break;
case 0x04:
errNo = EHOSTUNREACH;
break;
case 0x05:
errNo = ECONNREFUSED;
break;
case 0x06:
errNo = ETIMEDOUT;
break;
case 0x07:
errNo = EOPNOTSUPP;
break;
case 0x08:
errNo = EAFNOSUPPORT;
break;
default:
#ifdef EPROTO
errNo = EPROTO;
#else
errNo = 0;
#endif
break;
}
_exception = [[OFConnectIPSocketFailedException alloc]
initWithHost: _host
port: _port
socket: _socket
errNo: errNo];
[self didConnect];
return false;
}
/* Skip the rest of the response */
switch (response[3]) {
case 1: /* IPv4 */
_SOCKS5State = stateReadAddress;
[_socket asyncReadIntoBuffer: _buffer
exactLength: 4 + 2
runLoopMode: runLoopMode];
return false;
case 3: /* Domain name */
_SOCKS5State = stateReadAddressLength;
[_socket asyncReadIntoBuffer: _buffer
exactLength: 1
runLoopMode: runLoopMode];
return false;
case 4: /* IPv6 */
_SOCKS5State = stateReadAddress;
[_socket asyncReadIntoBuffer: _buffer
exactLength: 16 + 2
runLoopMode: runLoopMode];
return false;
default:
_exception = [[OFConnectIPSocketFailedException alloc]
initWithHost: _host
port: _port
socket: self
errNo: EPROTONOSUPPORT];
[self didConnect];
return false;
}
return false;
case stateReadAddress:
[self didConnect];
return false;
case stateReadAddressLength:
addressLength = buffer;
_SOCKS5State = stateReadAddress;
[_socket asyncReadIntoBuffer: _buffer
exactLength: addressLength[0] + 2
runLoopMode: runLoopMode];
return false;
default:
OFAssert(0);
return false;
}
}
- (OFData *)stream: (OFStream *)sock
didWriteData: (OFData *)data
bytesWritten: (size_t)bytesWritten
exception: (id)exception
{
OFRunLoopMode runLoopMode;
if (exception != nil) {
_exception = [exception retain];
[self didConnect];
return nil;
}
runLoopMode = [OFRunLoop currentRunLoop].currentMode;
switch (_SOCKS5State) {
case stateSendAuthentication:
_SOCKS5State = stateReadVersion;
[_socket asyncReadIntoBuffer: _buffer
exactLength: 2
runLoopMode: runLoopMode];
return nil;
case stateSendRequest:
[_request release];
_request = nil;
_SOCKS5State = stateReadResponse;
[_socket asyncReadIntoBuffer: _buffer
exactLength: 4
runLoopMode: runLoopMode];
return nil;
default:
OFAssert(0);
return nil;
}
}
@end