KasmVNC/common/rfb/SConnection.cxx
2020-09-20 12:16:44 +00:00

388 lines
10 KiB
C++

/* Copyright (C) 2002-2005 RealVNC Ltd. All Rights Reserved.
* Copyright 2011 Pierre Ossman for Cendio AB
*
* 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 <string.h>
#include <rfb/Exception.h>
#include <rfb/Security.h>
#include <rfb/msgTypes.h>
#include <rfb/fenceTypes.h>
#include <rfb/SMsgReader.h>
#include <rfb/SMsgWriter.h>
#include <rfb/SConnection.h>
#include <rfb/ServerCore.h>
#include <rfb/encodings.h>
#include <rfb/EncodeManager.h>
#include <rfb/SSecurity.h>
#include <rfb/LogWriter.h>
using namespace rfb;
static LogWriter vlog("SConnection");
// AccessRights values
const SConnection::AccessRights SConnection::AccessView = 0x0001;
const SConnection::AccessRights SConnection::AccessKeyEvents = 0x0002;
const SConnection::AccessRights SConnection::AccessPtrEvents = 0x0004;
const SConnection::AccessRights SConnection::AccessCutText = 0x0008;
const SConnection::AccessRights SConnection::AccessSetDesktopSize = 0x0010;
const SConnection::AccessRights SConnection::AccessNonShared = 0x0020;
const SConnection::AccessRights SConnection::AccessDefault = 0x03ff;
const SConnection::AccessRights SConnection::AccessNoQuery = 0x0400;
const SConnection::AccessRights SConnection::AccessFull = 0xffff;
SConnection::SConnection()
: readyForSetColourMapEntries(false),
is(0), os(0), reader_(0), writer_(0),
ssecurity(0), state_(RFBSTATE_UNINITIALISED),
preferredEncoding(encodingRaw)
{
defaultMajorVersion = 3;
defaultMinorVersion = 8;
if (rfb::Server::protocol3_3)
defaultMinorVersion = 3;
cp.setVersion(defaultMajorVersion, defaultMinorVersion);
}
SConnection::~SConnection()
{
if (ssecurity) ssecurity->destroy();
delete reader_;
reader_ = 0;
delete writer_;
writer_ = 0;
}
void SConnection::setStreams(rdr::InStream* is_, rdr::OutStream* os_)
{
is = is_;
os = os_;
}
void SConnection::initialiseProtocol()
{
cp.writeVersion(os);
state_ = RFBSTATE_PROTOCOL_VERSION;
}
void SConnection::processMsg()
{
switch (state_) {
case RFBSTATE_PROTOCOL_VERSION: processVersionMsg(); break;
case RFBSTATE_SECURITY_TYPE: processSecurityTypeMsg(); break;
case RFBSTATE_SECURITY: processSecurityMsg(); break;
case RFBSTATE_INITIALISATION: processInitMsg(); break;
case RFBSTATE_NORMAL: reader_->readMsg(); break;
case RFBSTATE_QUERYING:
throw Exception("SConnection::processMsg: bogus data from client while "
"querying");
case RFBSTATE_UNINITIALISED:
throw Exception("SConnection::processMsg: not initialised yet?");
default:
throw Exception("SConnection::processMsg: invalid state");
}
}
void SConnection::processVersionMsg()
{
vlog.debug("reading protocol version");
bool done;
if (!cp.readVersion(is, &done)) {
state_ = RFBSTATE_INVALID;
throw Exception("reading version failed: not an RFB client?");
}
if (!done) return;
vlog.info("Client needs protocol version %d.%d",
cp.majorVersion, cp.minorVersion);
if (cp.majorVersion != 3) {
// unknown protocol version
throwConnFailedException("Client needs protocol version %d.%d, server has %d.%d",
cp.majorVersion, cp.minorVersion,
defaultMajorVersion, defaultMinorVersion);
}
if (cp.minorVersion != 3 && cp.minorVersion != 7 && cp.minorVersion != 8) {
vlog.error("Client uses unofficial protocol version %d.%d",
cp.majorVersion,cp.minorVersion);
if (cp.minorVersion >= 8)
cp.minorVersion = 8;
else if (cp.minorVersion == 7)
cp.minorVersion = 7;
else
cp.minorVersion = 3;
vlog.error("Assuming compatibility with version %d.%d",
cp.majorVersion,cp.minorVersion);
}
versionReceived();
std::list<rdr::U8> secTypes;
std::list<rdr::U8>::iterator i;
secTypes = security.GetEnabledSecTypes();
if (cp.isVersion(3,3)) {
// cope with legacy 3.3 client only if "no authentication" or "vnc
// authentication" is supported.
for (i=secTypes.begin(); i!=secTypes.end(); i++) {
if (*i == secTypeNone || *i == secTypeVncAuth) break;
}
if (i == secTypes.end()) {
throwConnFailedException("No supported security type for %d.%d client",
cp.majorVersion, cp.minorVersion);
}
os->writeU32(*i);
if (*i == secTypeNone) os->flush();
state_ = RFBSTATE_SECURITY;
ssecurity = security.GetSSecurity(*i);
processSecurityMsg();
return;
}
// list supported security types for >=3.7 clients
if (secTypes.empty())
throwConnFailedException("No supported security types");
os->writeU8(secTypes.size());
for (i=secTypes.begin(); i!=secTypes.end(); i++)
os->writeU8(*i);
os->flush();
state_ = RFBSTATE_SECURITY_TYPE;
}
void SConnection::processSecurityTypeMsg()
{
vlog.debug("processing security type message");
int secType = is->readU8();
processSecurityType(secType);
}
void SConnection::processSecurityType(int secType)
{
// Verify that the requested security type should be offered
std::list<rdr::U8> secTypes;
std::list<rdr::U8>::iterator i;
secTypes = security.GetEnabledSecTypes();
for (i=secTypes.begin(); i!=secTypes.end(); i++)
if (*i == secType) break;
if (i == secTypes.end())
throw Exception("Requested security type not available");
vlog.info("Client requests security type %s(%d)",
secTypeName(secType),secType);
try {
state_ = RFBSTATE_SECURITY;
ssecurity = security.GetSSecurity(secType);
} catch (rdr::Exception& e) {
throwConnFailedException("%s", e.str());
}
processSecurityMsg();
}
void SConnection::processSecurityMsg()
{
vlog.debug("processing security message");
try {
bool done = ssecurity->processMsg(this);
if (done) {
state_ = RFBSTATE_QUERYING;
setAccessRights(ssecurity->getAccessRights());
queryConnection(ssecurity->getUserName());
}
} catch (AuthFailureException& e) {
vlog.error("AuthFailureException: %s", e.str());
os->writeU32(secResultFailed);
if (!cp.beforeVersion(3,8)) // 3.8 onwards have failure message
os->writeString(e.str());
os->flush();
throw;
}
}
void SConnection::processInitMsg()
{
vlog.debug("reading client initialisation");
reader_->readClientInit();
}
void SConnection::throwConnFailedException(const char* format, ...)
{
va_list ap;
char str[256];
va_start(ap, format);
(void) vsnprintf(str, sizeof(str), format, ap);
va_end(ap);
vlog.info("Connection failed: %s", str);
if (state_ == RFBSTATE_PROTOCOL_VERSION) {
if (cp.majorVersion == 3 && cp.minorVersion == 3) {
os->writeU32(0);
os->writeString(str);
os->flush();
} else {
os->writeU8(0);
os->writeString(str);
os->flush();
}
}
state_ = RFBSTATE_INVALID;
throw ConnFailedException(str);
}
void SConnection::writeConnFailedFromScratch(const char* msg,
rdr::OutStream* os)
{
os->writeBytes("RFB 003.003\n", 12);
os->writeU32(0);
os->writeString(msg);
os->flush();
}
void SConnection::setEncodings(int nEncodings, const rdr::S32* encodings)
{
int i;
preferredEncoding = encodingRaw;
for (i = 0;i < nEncodings;i++) {
if (EncodeManager::supported(encodings[i])) {
preferredEncoding = encodings[i];
break;
}
}
SMsgHandler::setEncodings(nEncodings, encodings);
}
void SConnection::supportsQEMUKeyEvent()
{
writer()->writeQEMUKeyEvent();
}
void SConnection::versionReceived()
{
}
void SConnection::authSuccess()
{
}
void SConnection::queryConnection(const char* userName)
{
approveConnection(true);
}
void SConnection::approveConnection(bool accept, const char* reason)
{
if (state_ != RFBSTATE_QUERYING)
throw Exception("SConnection::approveConnection: invalid state");
if (!cp.beforeVersion(3,8) || ssecurity->getType() != secTypeNone) {
if (accept) {
os->writeU32(secResultOK);
} else {
os->writeU32(secResultFailed);
if (!cp.beforeVersion(3,8)) { // 3.8 onwards have failure message
if (reason)
os->writeString(reason);
else
os->writeString("Authentication failure");
}
}
os->flush();
}
if (accept) {
state_ = RFBSTATE_INITIALISATION;
reader_ = new SMsgReader(this, is);
writer_ = new SMsgWriter(&cp, os);
authSuccess();
} else {
state_ = RFBSTATE_INVALID;
if (reason)
throw AuthFailureException(reason);
else
throw AuthFailureException();
}
}
void SConnection::clientInit(bool shared)
{
writer_->writeServerInit();
state_ = RFBSTATE_NORMAL;
}
void SConnection::setPixelFormat(const PixelFormat& pf)
{
SMsgHandler::setPixelFormat(pf);
readyForSetColourMapEntries = true;
if (!pf.trueColour)
writeFakeColourMap();
}
void SConnection::framebufferUpdateRequest(const Rect& r, bool incremental)
{
if (!readyForSetColourMapEntries) {
readyForSetColourMapEntries = true;
if (!cp.pf().trueColour) {
writeFakeColourMap();
}
}
}
void SConnection::fence(rdr::U32 flags, unsigned len, const char data[])
{
if (!(flags & fenceFlagRequest))
return;
// We cannot guarantee any synchronisation at this level
flags = 0;
writer()->writeFence(flags, len, data);
}
void SConnection::enableContinuousUpdates(bool enable,
int x, int y, int w, int h)
{
}
void SConnection::writeFakeColourMap(void)
{
int i;
rdr::U16 red[256], green[256], blue[256];
for (i = 0;i < 256;i++)
cp.pf().rgbFromPixel(i, &red[i], &green[i], &blue[i]);
writer()->writeSetColourMapEntries(0, 256, red, green, blue);
}