udpmessagesocket.cpp

KphoneSI (kpsi) is a SIP (Session Initiation Protocol) user agent for Linux, with which you can in

#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/ip.h>
#include <netinet/in.h>
#include <netdb.h>
#include <arpa/nameser.h>
#include <sys/ioctl.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <strings.h>
#include <errno.h>
#include <fcntl.h>
#include <resolv.h>
#include <qwidget.h>
#include "udpmessagesocket.h"
#include "sipclient.h"

UDPMessageSocket::UDPMessageSocket( void )
{
	type = SocketUDP;
	if ( ( socketfd = socket( AF_INET, SOCK_DGRAM, 0 ) ) == -1 ) {
		printf( "UDPMessageSocket::UDPMessageSocket(): socket() failed\n" );
	}
	didcomplain = false;
}


UDPMessageSocket::UDPMessageSocket( int newfd )
{
	type = SocketUDP;
	socketfd = newfd;
	didcomplain = false;
}



UDPMessageSocket::~UDPMessageSocket( void )
{
	close( socketfd );
}


int UDPMessageSocket::connect( unsigned int portnum )
{
	socketaddress.sin_family = AF_INET;
	socketaddress.sin_port = htons( portnum );
	socketaddress.sin_addr = *( (struct in_addr *) he->h_addr );
	bzero( &(socketaddress.sin_zero), 8 ); // is this portable?
	remoteaddress = socketaddress;
	return 0;
}


int UDPMessageSocket::SetTOS( void )
{
	unsigned char tos;
	socklen_t optlen;
	//tos=IPTOS_PREC_CRITIC_ECP;
	tos=IPTOS_LOWDELAY;
	optlen=1;
	if(setsockopt(socketfd,SOL_IP,IP_TOS,&tos,optlen) != 0){
		printf("UDPMessageSocket::SetTOS");
	}
	return 0;
}


int UDPMessageSocket::send( const char *sendbuffer, unsigned int length )
{
	int numbytes;
	if( ( numbytes = sendto( socketfd, sendbuffer, length, 0,
	    (struct sockaddr *) &remoteaddress, sizeof( struct sockaddr ) ) ) == -1 ) {
		if( !didcomplain ) {
			printf( "UDPMessageSocket::send(): sendto() failed\n" );
			didcomplain = true;
		}
		return -1;
	}
	return 0;
}


int UDPMessageSocket::receive( char *recvbuffer, unsigned int maxlength )
{
	socklen_t addrlength;
	int numbytes;
	addrlength = sizeof( struct sockaddr );
	if( ( numbytes = recvfrom( socketfd, recvbuffer, maxlength, 0, \
	    (struct sockaddr *) &remoteaddress, &addrlength ) ) == -1 ) {
		printf( "UDPMessageSocket::recieve(): recvfrom() failed\n" );
		return -1;
	}
	return numbytes;
}


unsigned int UDPMessageSocket::listen( unsigned int portnum )
{
	struct sockaddr name;
	socklen_t namesize;
	socketaddress.sin_family = AF_INET;
	socketaddress.sin_port = htons( portnum );
	socketaddress.sin_addr.s_addr = INADDR_ANY;
	bzero( &(socketaddress.sin_zero), 8 ); // is this portable?

	/*
	 * if already bound then close this one and open
	 * a new socket so we can bind it to different port
	 * number
	 */
	if (bound) {
		close(socketfd);
		bound = false;
		if( ( socketfd = socket( AF_INET, SOCK_DGRAM, 0 ) ) == -1 ) {
			printf( "UDPMessageSocket::listen: socket() failed\n" );
			return 0;
		}
	}

	int count = 0;
	while ( bind( socketfd, (struct sockaddr *) &socketaddress, sizeof( struct sockaddr) ) == -1 && count <= 10 ) {
		count++;
		portnum += 2;
		socketaddress.sin_port = htons( portnum );
	}
	if ( count > 10 ) {
		printf( "UDPMessageSocket::listen(): bind() failed\n" );
		return 0;
	}
	bound = true;
	namesize = sizeof( struct sockaddr );
	bzero( &name, sizeof( struct sockaddr ) );
	if ( getsockname( socketfd, &name, &namesize ) == -1 ) {
		printf( "UDPMessageSocket::listen(): getsockname() failed\n" );
		return 0;
	}
	ourport = ntohs( ((struct sockaddr_in *) &name)->sin_port );
	return ourport;
}

/*
 * FIXME: There is no guarantee that the subsequent call
 * to socket and bind will return previous port number + 1 !
 * This function can potentially allocate several file
 * descriptors and never close them
 * comment made by [e-mail]
 */
int UDPMessageSocket::listenOnEvenPortOS( void )
{
	struct sockaddr name;
	socklen_t namesize;
	int oldsocketfd = 0;
	int portnum = 0;

	/*
	 * if already bound then close this one and open
	 * a new socket so we can bind it to different port
	 * number
	 */
	if (bound) {
		close(socketfd);
		bound = false;
		if( ( socketfd = socket( AF_INET, SOCK_DGRAM, 0 ) ) == -1 ) {
			printf( "UDPMessageSocket::listenOnEvenPortOS: socket() failed\n" );
			return -1;
		}
	}

getaddress:
	socketaddress.sin_family = AF_INET;
	socketaddress.sin_port = htons( portnum );
	socketaddress.sin_addr.s_addr = INADDR_ANY;
	bzero( &(socketaddress.sin_zero), 8 ); // is this portable?
	if ( bind( socketfd, (struct sockaddr *) &socketaddress, sizeof( struct sockaddr) ) == -1 ) {
		printf( "UDPMessageSocket::listen(): bind() failed\n" );
		return -1;
	}
	bound = true;
	namesize = sizeof( struct sockaddr );
	bzero( &name, sizeof( struct sockaddr ) );
	if ( getsockname( socketfd, &name, &namesize ) == -1 ) {
		printf( "UDPMessageSocket::listen(): getsockname() failed\n" );
		return -1;
	}
	ourport = ntohs( ((struct sockaddr_in *) &name)->sin_port );
	if( ( portnum == 0 ) && ( ourport % 2 ) != 0 ) {
		oldsocketfd = socketfd;
		if( ( socketfd = socket( AF_INET, SOCK_DGRAM, 0 ) ) == -1 ) {
			printf( "UDPMessageSocket::UDPMessageSocket(): socket() failed\n" );
		}
		goto getaddress;
	}
	if( oldsocketfd != 0 )
		close( oldsocketfd );
	return 0;
}


int UDPMessageSocket::listenOnEvenPort(int min, int max)
{
	/* User didn't specify any range, let the OS
	 * assign source port number
	 */
	if ((min == 0) && (max == 0)) {
		return listenOnEvenPortOS();
	}

	/* Only max specified, set min to the lowest limit */
	if (min == 0) min = 1024;

	/* Only min specified, set max to the highest port number */
	if (max == 0) max = 65535;

	/* min not odd, increase */
	if (min % 2) min++;

	/* Out of range ? Signal error */
	if (min > max) goto error;

	/*
	 * if already bound then close this one and open
	 * a new socket so we can bind it to different port
	 * number
	 */
	if (bound) {
		close(socketfd);
		bound = false;
		if( ( socketfd = socket( AF_INET, SOCK_DGRAM, 0 ) ) == -1 ) {
			printf( "UDPMessageSocket::listenOnEvenPor: socket() failed\n" );
			return -1;
		}
	}

loop:
	socketaddress.sin_family = AF_INET;
	socketaddress.sin_port = htons(min);
	socketaddress.sin_addr.s_addr = INADDR_ANY;
	bzero(&(socketaddress.sin_zero), 8);
	if (bind(socketfd, (struct sockaddr*)&socketaddress, sizeof(struct sockaddr)) == -1) {
		min += 2;
		if (min <= max) goto loop;
		else goto error;
	}
	
	bound = true;

	/*
	 * FIXME: Do some test for even port number here
	 */

	ourport = min;
	return 0;

error:
	printf("UDPMessageSocket::listen(): Can't find a free port in specified range");
	return -1;
	
}


int UDPMessageSocket::listenOnEvenPortForVideo( void )
{
	struct sockaddr name;
	socklen_t namesize;
	int oldsocketfd = 0;
	int portnum = 0;

	if ( ( socketfd = socket( AF_INET, SOCK_DGRAM, 0 ) ) == -1 ) {
		printf( "UDPMessageSocket::UDPMessageSocket(): socket() failed\n" );
	}

getaddress:
	socketaddress.sin_family = AF_INET;
	socketaddress.sin_port = htons( portnum );
	socketaddress.sin_addr.s_addr = INADDR_ANY;
	bzero( &(socketaddress.sin_zero), 8 ); // is this portable?

	int one = 1;
	if ( setsockopt( socketfd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof( one ) ) == -1 ) {
		printf( "UDPMessageSocket::setsockopt SO_REUSEADDR\n" );
	}

	if ( bind( socketfd, (struct sockaddr *) &socketaddress, sizeof( struct sockaddr) ) == -1 ) {
		printf( "UDPMessageSocket::listen(): bind() failed\n" );
		return -1;
	}

	bound = true;

	namesize = sizeof( struct sockaddr );
	bzero( &name, sizeof( struct sockaddr ) );
	if ( getsockname( socketfd, &name, &namesize ) == -1 ) {
		printf( "UDPMessageSocket::listen(): getsockname() failed\n" );
		return -1;
	}
	ourport = ntohs( ((struct sockaddr_in *) &name)->sin_port );
	if( portnum == 0 && ( ourport % 4 ) != 0 ) {
		oldsocketfd = socketfd;
		if( ( socketfd = socket( AF_INET, SOCK_DGRAM, 0 ) ) == -1 ) {
			printf( "UDPMessageSocket::UDPMessageSocket(): socket() failed\n" );
		}
		goto getaddress;
	}
	if( oldsocketfd != 0 )
		close( oldsocketfd );

	return 0;
}


int UDPMessageSocket::accept( void )
{
	return socketfd;
}

int UDPMessageSocket::sendStunRequest( QString host, int port )
{
		setHostname( host);
		connect( port);
		StunRequestSimple req;
		req.msgHdr.msgType = htons(BindRequestMsg);
		req.msgHdr.msgLength = htons( sizeof(StunRequestSimple)-sizeof(StunMsgHdr) );
		for ( int i=0; i<16; ++i ) {
			req.msgHdr.id.octet[i]=0;
		}
		int id = rand();
		req.msgHdr.id.octet[0] = id;
		req.msgHdr.id.octet[1] = id>>8;
		req.msgHdr.id.octet[2] = id>>16;
		req.msgHdr.id.octet[3] = id>>24;
		return (send( (char *)&req, sizeof( req ) ) );
}


unsigned int UDPMessageSocket::receiveStunResponse(void )
{
	unsigned int port = 0;
	int i1,i2,i3,i4;
	char ip[17] = { '\0','\0','\0','\0','\0','\0','\0','\0','\0','\0','\0','\0','\0','\0','\0','\0','\0'};
	char inputbuf[ 8000 ];
	int bytesread;
	struct timeval timeout;
	fd_set read_fds;
	int highest_fd;
	timeout.tv_sec = 5;
	timeout.tv_usec = 0;
	FD_ZERO( &read_fds );
	FD_SET( getFileDescriptor(), &read_fds );
	highest_fd = getFileDescriptor() + 1;
retry:
	if( select( highest_fd, &read_fds, NULL, NULL, &timeout ) == -1 ) {
		if( errno == EINTR ) goto retry;
		perror( "UDPMessageSocket: select() punted" );
		exit( 1 );
	}
	if( FD_ISSET( getFileDescriptor(), &read_fds ) ) {
		bytesread = read( getFileDescriptor(), inputbuf, 8000 - 1 );
		StunMsgHdr* hdr = reinterpret_cast<StunMsgHdr*>( inputbuf );
		if( hdr->msgType == BindResponseMsg ) {
			char* body = inputbuf + sizeof( StunMsgHdr );
			unsigned int size = ntohs( hdr->msgLength );
			while( size > 0 ) {
				StunAtrHdr* attr = reinterpret_cast<StunAtrHdr*>( body );
				unsigned int hdrLen = ntohs( attr->length );
				if( ntohs( attr->type ) == MappedAddress ) {
					StunAtrAddress* attribute =
						reinterpret_cast<StunAtrAddress*>( body );
					if ( attribute->address.addrHdr.family == IPv4Family ) {
						StunAtrAddress4* atrAdd4 =
							reinterpret_cast<StunAtrAddress4*>( body );
						if ( hdrLen == sizeof( StunAtrAddress4 ) - 4 ) {
							port = ntohs( atrAdd4->addrHdr.port );
							i1 = atrAdd4->v4addr & 0xFF;
							i2 = (atrAdd4->v4addr & 0xFF00) >> 8;
							i3 = (atrAdd4->v4addr & 0xFF0000) >> 16;
							i4 = (atrAdd4->v4addr & 0xFF000000) >> 24;
							sprintf( ip, "%d.%d.%d.%d", i1, i2, i3, i4 );
							//printf( "UDPMessageSocket::receiveStunResponse %s:%d\n",ip,port);
							stunnedHost= QString((char *)&ip[0]);
						}
					}
				}
				body += hdrLen+4;
				size -= hdrLen+4;
			}
		}
	}
	return port;
}