StrCat() appends a string to an already existing string. In order to know where the existing string ends, it uses StrLen() which in turn uses strlen(), a function considered unsafe because it doesn't stop until it finds the null character.
Since the string was allocated but not initialized, StrCat() was either:
- Working correctly.
- Copying only a part of the string.
- Making the program crash via strlen().
The fix consists in using StrCpy(), which starts writing at the beginning of the string.
This allows an OpenVPN client to bypass a firewall which is aware of the protocol and is able to block it.
The XOR mask set on the server has to be the same on the client, otherwise it will not be able to connect with certain obfuscation modes.
A special OpenVPN client built with the "XOR patch" is required in order to use this function, because it has never been merged in the official OpenVPN repository.
Two parameters are added to the server configuration: "OpenVPNObfuscationMethod" and "OpenVPNObfuscationMask".
Their value can be retrieved with "OpenVpnObfuscationGet" and set with "OpenVpnObfuscationEnable" in the VPN Command Line Management Utility.
- Hash() has been removed because it was ambiguous, Md5() and Sha0() are proper replacements.
- HMacMd5() and HMacSha1() now share a common implementation handled by the new Internal_HMac() function.
- NewMd() and MdProcess() now support plain hashing (without the key).
- NewMd(), SetMdKey() and MdProcess() now check the OpenSSL functions' return value and in case of failure a debug message is printed along with the error string, if available.
- SetMdKey()'s return value has been changed from void to bool, so that it's possible to know whether the function succeeded or not.
- MdProcess()' return value has been changed from void to UINT (unsigned int) and the function now returns the number of bytes written by HMAC_Final() or EVP_DigestFinal_ex().
Hubname has to be set after copy or it will be an empty string. To get the real hubname (correct casing) we use it directly from the hub instead of the given parameter
[src/Cedar/Admin.c:13452] -> [src/Cedar/Admin.c:13492]: (warning) Either the condition 'cedar!=NULL' is redundant or there is possible null pointer dereference: cedar.
[src/Cedar/SM.c:18455] -> [src/Cedar/SM.c:18379]: (warning) Either the condition 'p!=NULL' is redundant or there is possible null pointer dereference: p.
[src/Cedar/SM.c:18455] -> [src/Cedar/SM.c:18491]: (warning) Either the condition 'p!=NULL' is redundant or there is possible null pointer dereference: p.
[src/Cedar/SM.c:18455] -> [src/Cedar/SM.c:18506]: (warning) Either the condition 'p!=NULL' is redundant or there is possible null pointer dereference: p.
[src/Cedar/Protocol.c:5190] -> [src/Cedar/Protocol.c:5115]: (warning) Either the condition 's!=NULL' is redundant or there is possible null pointer dereference: s.
[src/Cedar/Protocol.c:5190] -> [src/Cedar/Protocol.c:5145]: (warning) Either the condition 's!=NULL' is redundant or there is possible null pointer dereference: s.
[src/Cedar/Hub.c:5517] -> [src/Cedar/Hub.c:5553]: (warning) Either the condition 'dest!=NULL' is redundant or there is possible null pointer dereference: dest.
[src/Cedar/Hub.c:5517] -> [src/Cedar/Hub.c:5556]: (warning) Either the condition 'dest!=NULL' is redundant or there is possible null pointer dereference: dest.
[src/Cedar/Account.c:854]: (style) The function 'AddGroupTraffic' is never used.
[src/Mayaqua/Secure.c:1455]: (style) The function 'AddSecObjToEnumCache' is never used.
[src/Mayaqua/Network.c:18445]: (style) The function 'AddSockList' is never used.
[src/Cedar/Account.c:870]: (style) The function 'AddUserTraffic' is never used.
[src/Cedar/Server.c:1045]: (style) The function 'AdjoinEnumLogFile' is never used.
[src/Cedar/Admin.c:13780]: (style) The function 'AdminConnect' is never used.
[src/Mayaqua/Encrypt.c:855]: (style) The function 'BigNumToStr' is never used.
[src/Mayaqua/Str.c:2113]: (style) The function 'Bit128ToStr' is never used.
[src/Mayaqua/Encrypt.c:898]: (style) The function 'BufToBigNum' is never used.
[src/Mayaqua/Internat.c:1874]: (style) The function 'CalcStrToUtf8' is never used.
[src/Cedar/Hub.c:6689]: (style) The function 'CalcTrafficDiff' is never used.
[src/Mayaqua/Internat.c:1819]: (style) The function 'CalcUtf8ToStr' is never used.
[src/Mayaqua/Network.c:6495]: (style) The function 'CanGetTcpProcessId' is never used.
[src/Cedar/WinUi.c:7226]: (style) The function 'CbInsertStrA' is never used.
[src/Cedar/Client.c:3035]: (style) The function 'CcEnumObjectInSecure' is never used.
[src/Cedar/Client.c:2826]: (style) The function 'CcGetCommonProxySetting' is never used.
[src/Cedar/Client.c:2857]: (style) The function 'CcSetCommonProxySetting' is never used.
[src/Cedar/Cedar.c:575]: (style) The function 'CedarLog' is never used.
[src/Cedar/WinUi.c:9841]: (style) The function 'Center2' is never used.
[src/Mayaqua/Encrypt.c:814]: (style) The function 'CertTest' is never used.
[src/Mayaqua/Encrypt.c:809]: (style) The function 'CertTest2' is never used.
[src/Mayaqua/Encrypt.c:819]: (style) The function 'CertTest_' is never used.
[src/Mayaqua/Cfg.c:1705]: (style) The function 'CfgIsFolder' is never used.
* Allow specifying cipher suites instead of single ciphers.
CipherName now specifies all cipher suites instead of the
preferred cipher. This allows insecure ciphers like RC4 to
be permanently disabled, instead of being the default fallback
when the preferred cipher is unsupported.
CipherName is now left for OpenSSL to verify. Should it be
invalid, a secure default is used. The default CipherName setting
for new servers is one such invalid string: "~DEFAULT~". This
allows for future updates to change the default and the servers
can stay secure.
* Remove unused temporary variable.
[src/Cedar/Admin.c:11843] -> [src/Cedar/Admin.c:11845]: (warning) Either the condition 't==0' is redundant or there is possible null pointer dereference: t.
[src/Cedar/Admin.c:12316] -> [src/Cedar/Admin.c:12318]: (warning) Either the condition 'a==0' is redundant or there is possible null pointer dereference: a.
[src/Cedar/Admin.c:12576] -> [src/Cedar/Admin.c:12578]: (warning) Either the condition 't==0' is redundant or there is possible null pointer dereference: t.
[src/Cedar/Admin.c:12790] -> [src/Cedar/Admin.c:12792]: (warning) Either the condition 't==0' is redundant or there is possible null pointer dereference: t.
