/*
* socks5Connect establishes a socks 5 connection to destAddress on destPort. Returns 0 on error and 1 on success. See also
* initializeSocks5Protocol, sendSocks5ConnectRequest, and socksResponseValidate. reference https://www.ietf.org/rfc/rfc1928.txt
*/
static int socks5Connect(routerObject *this, char *destAddress, uint8_t destAddressBytesize, uint16_t destPort)
{
routerPrivate *private = NULL;
private = (routerPrivate *)this;
if(private == NULL || destAddress == NULL || this == NULL){
logger->log(logger, "Error", "Something was NULL that shouldn't have been", __FILE__, __LINE__);
return 0;
}
if( private->socket == -1 ){
logger->log(logger, "Error", "No socket established for router", __FILE__, __LINE__);
return 0;
}
if( !initializeSocks5Protocol(this) ){
logger->log(logger, "Error", "Failed to initialize socks protocol", __FILE__, __LINE__);
return 0;
}
if( !sendSocks5ConnectRequest(this, destAddress, destAddressBytesize, destPort) ){
logger->log(logger, "Error", "Failed to send socks request", __FILE__, __LINE__);
return 0;
}
if( !socksResponseValidate(this) ){
logger->log(logger, "Error", "Failed to establish socks connection", __FILE__, __LINE__);
return 0;
}
return 1;
}
/*
* ipv4Connect connects the router to address:port by setting the routers socket to the connected socket
* NOTE: address must be in ipv4 format
* returns 0 on error and 1 on success
*/
static int ipv4Connect(routerObject *this, char *ipv4Address, char *port)
{
struct addrinfo connectionInformation;
struct addrinfo *encodedAddress;
routerPrivate *private = NULL;
private = (routerPrivate *)this;
if(private == NULL || this == NULL || ipv4Address == NULL || port == NULL){
logger->log(logger, "Error", "Something was NULL that shouldn't have been", __FILE__, __LINE__);
return 0;
}
if(private->socket != -1){
logger->log(logger, "Error", "Router already in use", __FILE__, __LINE__);
return 0;
}
connectionInformation.ai_family = AF_INET;
connectionInformation.ai_socktype = SOCK_STREAM;
connectionInformation.ai_flags = 0;
connectionInformation.ai_protocol = 0;
connectionInformation.ai_canonname = 0;
connectionInformation.ai_addr = 0;
connectionInformation.ai_next = 0;
if( !this->setSocket( this, socket(AF_INET, SOCK_STREAM, 0) ) ){
logger->log(logger, "Error", "Failed to set socket", __FILE__, __LINE__);
return 0;
}
if(private->socket == -1){
logger->log(logger, "Error", "Failed to create new socket", __FILE__, __LINE__);
return 0;
}
if( !setSocketRecvTimeout(this, RECEIVE_WAIT_TIMEOUT_SECONDS, RECEIVE_WAIT_TIMEOUT_USECS) ){
logger->log(logger, "Error", "Failed to set socket properties", __FILE__, __LINE__);
return 0;
}
if( getaddrinfo(ipv4Address, port, (const struct addrinfo*)&connectionInformation, &encodedAddress) ){
logger->log(logger, "Error", "Failed to encode address", __FILE__, __LINE__);
return 0;
}
if( connect(private->socket, encodedAddress->ai_addr, encodedAddress->ai_addrlen) ){
logger->log(logger, "Error", "Failed to connect to ipv4 address", __FILE__, __LINE__);
return 0;
}
return 1;
}
/*
* ipv4Listen puts the router into a listening state by creating a socket bound to ipv4Address:port and listening on it
* returns 0 on error and 1 on success
*/
int ipv4Listen(routerObject *this, char *ipv4Address, int port)
{
struct sockaddr_in bindInfo;
struct in_addr formattedAddress;
routerPrivate *private = (routerPrivate *)this;
if(private == NULL || ipv4Address == NULL){
logger->log(logger, "Error", "Something was NULL that shouldn't have been", __FILE__, __LINE__);
return 0;
}
if(private->socket != -1){
logger->log(logger, "Error", "Router already in use", __FILE__, __LINE__);
return 0;
}
if( !this->setSocket(this, socket(AF_INET, SOCK_STREAM, 0)) ){
logger->log(logger, "Error", "Failed to set socket", __FILE__, __LINE__);
return 0;
}
if(private->socket == -1){
logger->log(logger, "Error", "Failed to create socket", __FILE__, __LINE__);
return 0;
}
if( !inet_aton( (const char*)ipv4Address , &formattedAddress) ){
logger->log(logger, "Error", "Failed to convert IP bind address to network order", __FILE__, __LINE__);
return 0;
}
bindInfo.sin_family = AF_INET;
bindInfo.sin_port = htons(port);
bindInfo.sin_addr.s_addr = formattedAddress.s_addr;
if( bind(private->socket, (const struct sockaddr*) &bindInfo, sizeof(bindInfo)) ){
logger->log(logger, "Error", "Failed to bind to address", __FILE__, __LINE__);
return 0;
}
if( listen(private->socket, SOMAXCONN) ){
logger->log(logger, "Error", "SFailed to listen on socket", __FILE__, __LINE__);
return 0;
}
return 1;
}
/*
* getConnection gets a connection on the listening socket, which must already be initialized (see ipv4Listen)
* returns -1 on error and the accepted connection on success
*/
static int getConnection(routerObject *this)
{
routerPrivate *private = (routerPrivate *)this;
if( !logger->assert( logger , private != NULL , "Something was NULL that shouldn't have been" ) { return -1; }
if( !logger->assert( logger , private->socket != -1 , "Uninitialized socket, cannot accept" ) { return -1; }
return accept(private->socket, NULL, NULL);
}
/*
* setSocket sets the routers socket to the argument socket
* returns 0 on error and 1 on success
*/
static int setSocket(routerObject *this, int socket)
{
routerPrivate *private = (routerPrivate *)this;
if( !logger->assert(logger, private != NULL, "Something was NULL that shouldn't have been") ) return 0;
private->socket = socket;
return 1;
}
/************ PRIVATE METHODS ******************/
/*
* setSocketRecvTimeout sets how long the routers socket will idle waiting for incoming network traffic for
* (when it is actually expecting incoming network traffic). If the timeout period expires with no new data
* received from the network (while it is being expected), an error occurs.
*
* returns 0 on error and 1 on success.
*/
static int setSocketRecvTimeout(routerObject *this, int timeoutSecs, int timeoutUsecs)
{
struct timeval recvTimeout;
routerPrivate *private = (routerPrivate *)this;
//if no data received after timeoutsecs + timeoutUsecs (while expecting data) then error out
recvTimeout.tv_sec = timeoutSecs;
recvTimeout.tv_usec = timeoutUsecs;
return(
logger->assert(logger , private != NULL , "Something was NULL that shouldn't have been" ) &&
logger->assert(logger , private->socket != -1 , "Router doesn't have a socket" ) &&
logger->assert(logger , !setsockopt(private->socket, SOL_SOCKET, SO_RCVTIMEO, &recvTimeout, sizeof(recvTimeout)) , "Failed to set timeout on socket" )
);
}
/* reference https://www.ietf.org/rfc/rfc1928.txt
*
* initializeSocks5protocol engages in the first part of the socks5 protocol, primarily ensuring the server supports socks 5
* this function also ensures the server doesn't expect authentication, router.c doesn't currently
* support socks with authentication.
*
* returns 1 on success, 0 on error (or failure in that the proxy server doesn't support our requirements).
*
*/
static int initializeSocks5Protocol(routerObject *this)
{
char proxyResponse[2];
return(
logger->assert( logger , this != NULL , "something was NULL that shouldn't have been" ) &&
logger->assert( logger , this->transmit(this, "\005\001\000", 3) , "Socks connection failed to transmit bytes to socks server" ) &&
logger->assert( logger , this->receive(this, &proxyResponse, 2) , "Failed to get response from proxy" ) &&
logger->assert( logger , proxyResponse[0] == 5 , "Proxy doesn't think it is socks5" ) &&
logger->assert( logger , proxyResponse[1] == 0 , "Proxy expects authentication" )
);
}
/*
* sendSocks5ConnectionRequest engages in the second part of the socks5 protocol, primarily attempting to establish a
* connection to destAddress:destPort through the socks proxy. reference https://www.ietf.org/rfc/rfc1928.txt
*
* returns 0 on error (or failure), 1 on success.
* NOTE: desAddress should be a URL (I don't think this currently supports IP addresses, but TODO I should look into this)
*/
/* CLIENT REQUEST FORMAT
*
* note destAddress is prepended with one octet specifying its bytesize
*
* +----+-----+-------+------+----------+----------+
* |VER | CMD | RSV | ATYP | DST.ADDR | DST.PORT |
* +----+-----+-------+------+----------+----------+
* | 1 | 1 | X'00' | 1 | Variable | 2 |
* +----+-----+-------+------+----------+----------+
*
*/ //TODO wipe stack when done look at memory manager to make sure can do this
static int sendSocks5ConnectRequest(routerObject *this, char *destAddress, uint8_t destAddressBytesize, uint16_t destPort)
{
int fixedSocksBytes = 1 + 1 + 1 + 1 + 1 + 2;
int maxDestAddressBytesize = 100;
char socksRequest[fixedSocksBytes + maxDestAddressBytesize];
int requestBytesize = fixedSocksBytes + destAddressBytesize; //TODO look into cast differences, make sure it is legit
if(requestBytesize > fixedSocksBytes + maxDestAddressBytesize){
logger->log(logger, "Error", "Dest address bytesize must be 100 or less", __FILE__, __LINE__);
return 0;
}
if(this == NULL || destAddress == NULL){
logger->log(logger, "Error", "Something was NULL that shouldn't have been", __FILE__, __LINE__);
return 0;
}
//format the destination port in network order
destPort = htons(destPort);
//first four bytes: socks version 5, command is connect, rsv is null, identifier is domain name
memcpy(&socksRequest[0], "\005\001\000\003", 4);
//fifth byte: prepend identifier with its bytesize
memcpy(&socksRequest[4], &destAddressBytesize, 1);
//variable bytes: the destination identifier
memcpy(&socksRequest[5], destAddress, destAddressBytesize);
//final two bytes: the destination port in network octet order
memcpy(&socksRequest[5 + destAddressBytesize], &destPort, 2);
if( !this->transmit(this, socksRequest, requestBytesize) ){
logger->log(logger, "Error", "Failed to transmit message to socks server", __FILE__, __LINE__);
return 0;
}
return 1;
}
/*
* socksResponseValidate gets the final response from the socks server and ensures that everything has gone correctly.
* reference https://www.ietf.org/rfc/rfc1928.txt
*
* returns 0 on error (or failure) and 1 on success.
*
*/
static int socksResponseValidate(routerObject *this)
{
char proxyResponse[10];
if(this == NULL){
logger->log(logger, "Error", "Something was NULL that shouldn't have been", __FILE__, __LINE__);
return 0;
}
/* PROXY RESPONSE FORMAT
*
* +----+-----+-------+------+----------+----------+
* |VER | REP | RSV | ATYP | BND.ADDR | BND.PORT |
* +----+-----+-------+------+----------+----------+
* | 1 | 1 | X'00' | 1 | Variable | 2 |
* +----+-----+-------+------+----------+----------+
*/
if( !this->receive(this, &proxyResponse, 10) ){
logger->log(logger, "Error", "Failed to receive proxy response", __FILE__, __LINE__);
return 0;
}
if(proxyResponse[0] != 5){
logger->log(logger, "Error", "Socks server doesn't think it is version 5", __FILE__, __LINE__);
return 0;
}
if(proxyResponse[1] != 0){
logger->log(logger, "Error", "Connection failed", __FILE__, __LINE__);
return 0;
}
return 1;
}
