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Diffstat (limited to 'nxcomp/src/ProxyReadBuffer.cpp')
| -rw-r--r-- | nxcomp/src/ProxyReadBuffer.cpp | 211 |
1 files changed, 211 insertions, 0 deletions
diff --git a/nxcomp/src/ProxyReadBuffer.cpp b/nxcomp/src/ProxyReadBuffer.cpp new file mode 100644 index 000000000..77f12771b --- /dev/null +++ b/nxcomp/src/ProxyReadBuffer.cpp @@ -0,0 +1,211 @@ +/**************************************************************************/ +/* */ +/* Copyright (c) 2001, 2011 NoMachine (http://www.nomachine.com) */ +/* Copyright (c) 2008-2014 Oleksandr Shneyder <o.shneyder@phoca-gmbh.de> */ +/* Copyright (c) 2014-2016 Ulrich Sibiller <uli42@gmx.de> */ +/* Copyright (c) 2014-2016 Mihai Moldovan <ionic@ionic.de> */ +/* Copyright (c) 2011-2016 Mike Gabriel <mike.gabriel@das-netzwerkteam.de>*/ +/* Copyright (c) 2015-2016 Qindel Group (http://www.qindel.com) */ +/* */ +/* NXCOMP, NX protocol compression and NX extensions to this software */ +/* are copyright of the aforementioned persons and companies. */ +/* */ +/* Redistribution and use of the present software is allowed according */ +/* to terms specified in the file LICENSE.nxcomp which comes in the */ +/* source distribution. */ +/* */ +/* All rights reserved. */ +/* */ +/* NOTE: This software has received contributions from various other */ +/* contributors, only the core maintainers and supporters are listed as */ +/* copyright holders. Please contact us, if you feel you should be listed */ +/* as copyright holder, as well. */ +/* */ +/**************************************************************************/ + +#ifdef HAVE_CONFIG_H +#include "config.h" +#endif + +#include "ProxyReadBuffer.h" + +#include "Transport.h" + +// +// Set the verbosity level. You also +// need to define DUMP in Misc.cpp +// if DUMP is defined here. +// + +#define WARNING +#define PANIC +#undef TEST +#undef DEBUG +#undef DUMP + +unsigned int ProxyReadBuffer::suggestedLength(unsigned int pendingLength) +{ + // + // Always read all the data that + // is available. + // + + int readable = transport_ -> readable(); + + unsigned int readLength = (readable == -1 ? 0 : (unsigned int) readable); + + if (readLength < pendingLength) + { + readLength = pendingLength; + } + + // + // Even if the readable data is not + // enough to make a complete message, + // resize the buffer to accommodate + // it all. + // + + if (pendingLength < remaining_) + { + readLength = remaining_; + } + + return readLength; +} + +int ProxyReadBuffer::locateMessage(const unsigned char *start, + const unsigned char *end, + unsigned int &controlLength, + unsigned int &dataLength, + unsigned int &trailerLength) +{ + unsigned int lengthLength = 0; + const unsigned char *nextSrc = start; + unsigned char next; + + dataLength = 0; + + #ifdef TEST + *logofs << "ProxyReadBuffer: Locating message for FD#" + << transport_ -> fd() << " with " << end - start + << " bytes.\n" << logofs_flush; + #endif + + // + // Use something like the following if + // you are looking for errors. + // + + #ifdef DUMP + if (control -> ProxyMode == proxy_server && start < end && + transport_ -> fd() == 6 || transport_ -> fd() == 11) + { + *logofs << "ProxyReadBuffer: Partial checksums are:\n"; + + DumpBlockChecksums(start, end - start, 256); + + *logofs << logofs_flush; + } + #endif + + do + { + if (nextSrc >= end) + { + remaining_ = 1; + + #ifdef TEST + *logofs << "ProxyReadBuffer: No message was located " + << "with remaining " << remaining_ << ".\n" + << logofs_flush; + #endif + + return 0; + } + + next = *nextSrc++; + + dataLength <<= 7; + dataLength |= (unsigned int) (next & 0x7f); + + lengthLength++; + } + while (next & 0x80); + + unsigned int totalLength; + + if (dataLength == 0) + { + trailerLength = 0; + controlLength = 3; + totalLength = controlLength; + } + else + { + trailerLength = lengthLength; + controlLength = 0; + totalLength = dataLength + trailerLength; + } + + if (start + totalLength > end) + { + // + // When having to decompress a ZLIB stream, + // a single byte can be enough to complete + // the frame. + // + + if (control -> RemoteStreamCompression == 0) + { + remaining_ = totalLength - (end - start); + } + else + { + remaining_ = 1; + } + + #ifdef TEST + *logofs << "ProxyReadBuffer: No message was located " + << "with remaining " << remaining_ << ".\n" + << logofs_flush; + #endif + + return 0; + } + else + { + #ifdef DUMP + *logofs << "ProxyReadBuffer: Received " << totalLength << " bytes of data " + << "with checksum "; + + DumpChecksum(start, totalLength); + + *logofs << " on proxy FD#" << transport_ -> fd() << ".\n" << logofs_flush; + #endif + + #if defined(TEST) || defined(INFO) + *logofs << "ProxyReadBuffer: Produced plain input for " << dataLength + << "+" << trailerLength << "+" << controlLength << " bytes out of " + << totalLength << " bytes.\n" << logofs_flush; + #endif + + #ifdef DUMP + *logofs << "ProxyReadBuffer: Partial checksums are:\n"; + + DumpBlockChecksums(start, totalLength, 256); + + *logofs << logofs_flush; + #endif + + remaining_ = 0; + + #ifdef TEST + *logofs << "ProxyReadBuffer: Located message with " + << "remaining " << remaining_ << ".\n" + << logofs_flush; + #endif + + return 1; + } +} |