diff options
Diffstat (limited to 'krfb/libvncserver/sockets.c')
-rw-r--r-- | krfb/libvncserver/sockets.c | 592 |
1 files changed, 592 insertions, 0 deletions
diff --git a/krfb/libvncserver/sockets.c b/krfb/libvncserver/sockets.c new file mode 100644 index 00000000..69c4810a --- /dev/null +++ b/krfb/libvncserver/sockets.c @@ -0,0 +1,592 @@ +/* + * sockets.c - deal with TCP & UDP sockets. + * + * This code should be independent of any changes in the RFB protocol. It just + * deals with the X server scheduling stuff, calling rfbNewClientConnection and + * rfbProcessClientMessage to actually deal with the protocol. If a socket + * needs to be closed for any reason then rfbCloseClient should be called, and + * this in turn will call rfbClientConnectionGone. To make an active + * connection out, call rfbConnect - note that this does _not_ call + * rfbNewClientConnection. + * + * This file is divided into two types of function. Those beginning with + * "rfb" are specific to sockets using the RFB protocol. Those without the + * "rfb" prefix are more general socket routines (which are used by the http + * code). + * + * Thanks to Karl Hakimian for pointing out that some platforms return EAGAIN + * not EWOULDBLOCK. + */ + +/* + * OSXvnc Copyright (C) 2001 Dan McGuirk <mcguirk@incompleteness.net>. + * Original Xvnc code Copyright (C) 1999 AT&T Laboratories Cambridge. + * All Rights Reserved. + * + * This is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This software 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 General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this software; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, + * USA. + */ + +#include <stdio.h> +#include <sys/types.h> +#ifdef WIN32 +#pragma warning (disable: 4018 4761) +#define close closesocket +#define read(sock,buf,len) recv(sock,buf,len,0) +#define EWOULDBLOCK WSAEWOULDBLOCK +#define ETIMEDOUT WSAETIMEDOUT +#define write(sock,buf,len) send(sock,buf,len,0) +#else +#include <sys/time.h> +#include <sys/socket.h> +#include <netinet/in.h> +#include <netinet/tcp.h> +#include <netdb.h> +#include <unistd.h> +#include <arpa/inet.h> +#endif +#if defined(__osf__) +typedef int socklen_t; +#endif +#if defined(__linux__) && defined(NEED_TIMEVAL) +struct timeval +{ + long int tv_sec,tv_usec; +} +; +#endif +#include <fcntl.h> +#include <errno.h> + +#ifdef USE_LIBWRAP +#include <syslog.h> +#include <tcpd.h> +int allow_severity=LOG_INFO; +int deny_severity=LOG_WARNING; +#endif + +#include "rfb.h" + +/*#ifndef WIN32 +int max(int i,int j) { return(i<j?j:i); } +#endif +*/ + +int rfbMaxClientWait = 20000; /* time (ms) after which we decide client has + gone away - needed to stop us hanging */ + +/* + * rfbInitSockets sets up the TCP and UDP sockets to listen for RFB + * connections. It does nothing if called again. + */ + +void +rfbInitSockets(rfbScreenInfoPtr rfbScreen) +{ + if (rfbScreen->socketInitDone) + return; + + rfbScreen->socketInitDone = TRUE; + + if (rfbScreen->inetdSock != -1) { + const int one = 1; + +#ifndef WIN32 + if (fcntl(rfbScreen->inetdSock, F_SETFL, O_NONBLOCK) < 0) { + rfbLogPerror("fcntl"); + exit(1); + } +#endif + + if (setsockopt(rfbScreen->inetdSock, IPPROTO_TCP, TCP_NODELAY, + (char *)&one, sizeof(one)) < 0) { + rfbLogPerror("setsockopt"); + exit(1); + } + + FD_ZERO(&(rfbScreen->allFds)); + FD_SET(rfbScreen->inetdSock, &(rfbScreen->allFds)); + rfbScreen->maxFd = rfbScreen->inetdSock; + return; + } + + if(rfbScreen->autoPort) { + int i; + rfbLog("Autoprobing TCP port \n"); + + for (i = 5900; i < 6000; i++) { + if ((rfbScreen->rfbListenSock = ListenOnTCPPort(i)) >= 0) { + rfbScreen->rfbPort = i; + break; + } + } + + if (i >= 6000) { + rfbLogPerror("Failure autoprobing"); + exit(1); + } + + rfbLog("Autoprobing selected port %d\n", rfbScreen->rfbPort); + FD_ZERO(&(rfbScreen->allFds)); + FD_SET(rfbScreen->rfbListenSock, &(rfbScreen->allFds)); + rfbScreen->maxFd = rfbScreen->rfbListenSock; + } + else if(rfbScreen->rfbPort>0) { + rfbLog("Listening for VNC connections on TCP port %d\n", rfbScreen->rfbPort); + + if ((rfbScreen->rfbListenSock = ListenOnTCPPort(rfbScreen->rfbPort)) < 0) { + rfbLogPerror("ListenOnTCPPort"); + exit(1); + } + + FD_ZERO(&(rfbScreen->allFds)); + FD_SET(rfbScreen->rfbListenSock, &(rfbScreen->allFds)); + rfbScreen->maxFd = rfbScreen->rfbListenSock; + } + + if (rfbScreen->udpPort != 0) { + rfbLog("rfbInitSockets: listening for input on UDP port %d\n",rfbScreen->udpPort); + + if ((rfbScreen->udpSock = ListenOnUDPPort(rfbScreen->udpPort)) < 0) { + rfbLogPerror("ListenOnUDPPort"); + exit(1); + } + FD_SET(rfbScreen->udpSock, &(rfbScreen->allFds)); + rfbScreen->maxFd = max((int)rfbScreen->udpSock,rfbScreen->maxFd); + } +} + + +/* + * rfbCheckFds is called from ProcessInputEvents to check for input on the RFB + * socket(s). If there is input to process, the appropriate function in the + * RFB server code will be called (rfbNewClientConnection, + * rfbProcessClientMessage, etc). + */ + +void +rfbCheckFds(rfbScreenInfoPtr rfbScreen,long usec) +{ + int nfds; + fd_set fds; + struct timeval tv; + struct sockaddr_in addr; + size_t addrlen = sizeof(addr); + char buf[6]; + const int one = 1; + int sock; + rfbClientIteratorPtr i; + rfbClientPtr cl; + + if (!rfbScreen->inetdInitDone && rfbScreen->inetdSock != -1) { + rfbNewClientConnection(rfbScreen,rfbScreen->inetdSock); + rfbScreen->inetdInitDone = TRUE; + } + + memcpy((char *)&fds, (char *)&(rfbScreen->allFds), sizeof(fd_set)); + tv.tv_sec = 0; + tv.tv_usec = usec; + nfds = select(rfbScreen->maxFd + 1, &fds, NULL, NULL /* &fds */, &tv); + if (nfds == 0) { + return; + } + if (nfds < 0) { +#ifdef WIN32 + errno = WSAGetLastError(); +#endif + rfbLogPerror("rfbCheckFds: select"); + return; + } + + if (rfbScreen->rfbListenSock != -1 && FD_ISSET(rfbScreen->rfbListenSock, &fds)) { + + if ((sock = accept(rfbScreen->rfbListenSock, + (struct sockaddr *)&addr, &addrlen)) < 0) { + rfbLogPerror("rfbCheckFds: accept"); + return; + } + +#ifndef WIN32 + if (fcntl(sock, F_SETFL, O_NONBLOCK) < 0) { + rfbLogPerror("rfbCheckFds: fcntl"); + close(sock); + return; + } +#endif + + if (setsockopt(sock, IPPROTO_TCP, TCP_NODELAY, + (char *)&one, sizeof(one)) < 0) { + rfbLogPerror("rfbCheckFds: setsockopt"); + close(sock); + return; + } + +#ifdef USE_LIBWRAP + if(!hosts_ctl("vnc",STRING_UNKNOWN,inet_ntoa(addr.sin_addr), + STRING_UNKNOWN)) { + rfbLog("Rejected connection from client %s\n", + inet_ntoa(addr.sin_addr)); + close(sock); + return; + } +#endif + + rfbLog("Got connection from client %s\n", inet_ntoa(addr.sin_addr)); + + rfbNewClient(rfbScreen,sock); + + FD_CLR(rfbScreen->rfbListenSock, &fds); + if (--nfds == 0) + return; + } + + if ((rfbScreen->udpSock != -1) && FD_ISSET(rfbScreen->udpSock, &fds)) { + if(!rfbScreen->udpClient) + rfbNewUDPClient(rfbScreen); + if (recvfrom(rfbScreen->udpSock, buf, 1, MSG_PEEK, + (struct sockaddr *)&addr, &addrlen) < 0) { + rfbLogPerror("rfbCheckFds: UDP: recvfrom"); + rfbDisconnectUDPSock(rfbScreen); + rfbScreen->udpSockConnected = FALSE; + } else { + if (!rfbScreen->udpSockConnected || + (memcmp(&addr, &rfbScreen->udpRemoteAddr, addrlen) != 0)) + { + /* new remote end */ + rfbLog("rfbCheckFds: UDP: got connection\n"); + + memcpy(&rfbScreen->udpRemoteAddr, &addr, addrlen); + rfbScreen->udpSockConnected = TRUE; + + if (connect(rfbScreen->udpSock, + (struct sockaddr *)&addr, addrlen) < 0) { + rfbLogPerror("rfbCheckFds: UDP: connect"); + rfbDisconnectUDPSock(rfbScreen); + return; + } + + rfbNewUDPConnection(rfbScreen,rfbScreen->udpSock); + } + + rfbProcessUDPInput(rfbScreen); + } + + FD_CLR(rfbScreen->udpSock, &fds); + if (--nfds == 0) + return; + } + + i = rfbGetClientIterator(rfbScreen); + while((cl = rfbClientIteratorNext(i))) { + if (cl->onHold) + continue; + if (FD_ISSET(cl->sock, &fds) && FD_ISSET(cl->sock, &(rfbScreen->allFds))) + rfbProcessClientMessage(cl); + } + rfbReleaseClientIterator(i); +} + + +void +rfbDisconnectUDPSock(rfbScreenInfoPtr rfbScreen) +{ + rfbScreen->udpSockConnected = FALSE; +} + + + +void +rfbCloseClient(cl) + rfbClientPtr cl; +{ + LOCK(cl->updateMutex); + if (cl->sock != -1) { + FD_CLR(cl->sock,&(cl->screen->allFds)); + shutdown(cl->sock,SHUT_RDWR); + close(cl->sock); + cl->sock = -1; + } + TSIGNAL(cl->updateCond); + UNLOCK(cl->updateMutex); +} + + +/* + * rfbConnect is called to make a connection out to a given TCP address. + */ + +int +rfbConnect(rfbScreen, host, port) + rfbScreenInfoPtr rfbScreen; + char *host; + int port; +{ + int sock; + int one = 1; + + rfbLog("Making connection to client on host %s port %d\n", + host,port); + + if ((sock = ConnectToTcpAddr(host, port)) < 0) { + rfbLogPerror("connection failed"); + return -1; + } + +#ifndef WIN32 + if (fcntl(sock, F_SETFL, O_NONBLOCK) < 0) { + rfbLogPerror("fcntl failed"); + close(sock); + return -1; + } +#endif + + if (setsockopt(sock, IPPROTO_TCP, TCP_NODELAY, + (char *)&one, sizeof(one)) < 0) { + rfbLogPerror("setsockopt failed"); + close(sock); + return -1; + } + + /* AddEnabledDevice(sock); */ + FD_SET(sock, &rfbScreen->allFds); + rfbScreen->maxFd = max(sock,rfbScreen->maxFd); + + return sock; +} + +/* + * ReadExact reads an exact number of bytes from a client. Returns 1 if + * those bytes have been read, 0 if the other end has closed, or -1 if an error + * occurred (errno is set to ETIMEDOUT if it timed out). + * timeout is the timeout in ms, 0 for no timeout. + */ + +int +ReadExactTimeout(rfbClientPtr cl, char* buf, int len, int timeout) +{ + int sock = cl->sock; + int n; + fd_set fds; + struct timeval tv; + int to = 20000; + if (timeout) + to = timeout; + + while (len > 0) { + n = read(sock, buf, len); + + if (n > 0) { + + buf += n; + len -= n; + + } else if (n == 0) { + + return 0; + + } else { +#ifdef WIN32 + errno = WSAGetLastError(); +#endif + if (errno != EWOULDBLOCK && errno != EAGAIN) { + return n; + } + + FD_ZERO(&fds); + FD_SET(sock, &fds); + tv.tv_sec = to / 1000; + tv.tv_usec = (to % 1000) * 1000; + n = select(sock+1, &fds, NULL, &fds, &tv); + if (n < 0) { + rfbLogPerror("ReadExact: select"); + return n; + } + if ((n == 0) && timeout) { + errno = ETIMEDOUT; + return -1; + } + } + } + return 1; +} + +int ReadExact(rfbClientPtr cl,char* buf,int len) +{ + return ReadExactTimeout(cl, buf, len, 0); +} + +/* + * WriteExact writes an exact number of bytes to a client. Returns 1 if + * those bytes have been written, or -1 if an error occurred (errno is set to + * ETIMEDOUT if it timed out). + */ + +int +WriteExact(cl, buf, len) + rfbClientPtr cl; + const char *buf; + int len; +{ + int sock = cl->sock; + int n; + fd_set fds; + struct timeval tv; + int totalTimeWaited = 0; + + LOCK(cl->outputMutex); + while (len > 0) { + n = write(sock, buf, len); + + if (n > 0) { + + buf += n; + len -= n; + + } else if (n == 0) { + + rfbLog("WriteExact: write returned 0?\n"); + exit(1); + + } else { +#ifdef WIN32 + errno = WSAGetLastError(); +#endif + if (errno != EWOULDBLOCK && errno != EAGAIN) { + UNLOCK(cl->outputMutex); + return n; + } + + /* Retry every 5 seconds until we exceed rfbMaxClientWait. We + need to do this because select doesn't necessarily return + immediately when the other end has gone away */ + + FD_ZERO(&fds); + FD_SET(sock, &fds); + tv.tv_sec = 5; + tv.tv_usec = 0; + n = select(sock+1, NULL, &fds, NULL /* &fds */, &tv); + if (n < 0) { + rfbLogPerror("WriteExact: select"); + UNLOCK(cl->outputMutex); + return n; + } + if (n == 0) { + totalTimeWaited += 5000; + if (totalTimeWaited >= rfbMaxClientWait) { + errno = ETIMEDOUT; + UNLOCK(cl->outputMutex); + return -1; + } + } else { + totalTimeWaited = 0; + } + } + } + UNLOCK(cl->outputMutex); + return 1; +} + +int +ListenOnTCPPort(port) + int port; +{ + struct sockaddr_in addr; + int sock; + int one = 1; + + addr.sin_family = AF_INET; + addr.sin_port = htons(port); + /* addr.sin_addr.s_addr = interface.s_addr; */ + addr.sin_addr.s_addr = INADDR_ANY; + + if ((sock = socket(AF_INET, SOCK_STREAM, 0)) < 0) { + return -1; + } + if (setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, + (char *)&one, sizeof(one)) < 0) { + close(sock); + return -1; + } + if (bind(sock, (struct sockaddr *)&addr, sizeof(addr)) < 0) { + close(sock); + return -1; + } + if (listen(sock, 5) < 0) { + close(sock); + return -1; + } + + return sock; +} + +int +ConnectToTcpAddr(host, port) + char *host; + int port; +{ + struct hostent *hp; + int sock; + struct sockaddr_in addr; + + addr.sin_family = AF_INET; + addr.sin_port = htons(port); + + if ((addr.sin_addr.s_addr = inet_addr(host)) == INADDR_NONE) + { + if (!(hp = gethostbyname(host))) { + errno = EINVAL; + return -1; + } + addr.sin_addr.s_addr = *(unsigned long *)hp->h_addr; + } + + if ((sock = socket(AF_INET, SOCK_STREAM, 0)) < 0) { + return -1; + } + + if (connect(sock, (struct sockaddr *)&addr, (sizeof(addr))) < 0) { + close(sock); + return -1; + } + + return sock; +} + +int +ListenOnUDPPort(port) + int port; +{ + struct sockaddr_in addr; + int sock; + int one = 1; + + addr.sin_family = AF_INET; + addr.sin_port = htons(port); + /* addr.sin_addr.s_addr = interface.s_addr; */ + addr.sin_addr.s_addr = INADDR_ANY; + + if ((sock = socket(AF_INET, SOCK_DGRAM, 0)) < 0) { + return -1; + } + if (setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, + (char *)&one, sizeof(one)) < 0) { + return -1; + } + if (bind(sock, (struct sockaddr *)&addr, sizeof(addr)) < 0) { + return -1; + } + + return sock; +} |