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.
resolve possible null pointer dereference
found by cppcheck
[src/Cedar/Protocol.c:3138] -> [src/Cedar/Protocol.c:3071]: (warning) Either the condition 's!=NULL' is redundant or there is possible null pointer dereference: s.
[src/Cedar/Protocol.c:916]: (style) Variable 'save' is assigned a value that is never used.
[src/Cedar/Protocol.c:6242]: (style) Variable 'size' is assigned a value that is never used.
[src/Cedar/Protocol.c:778]: (style) Variable 'old_disable' is assigned a value that is never used.
[src/Cedar/Protocol.c:1021]: (style) Variable 'save' is assigned a value that is never used.
[src/Cedar/Protocol.c:3708]: (style) Variable 'is_vgc' is assigned a value that is never used.
[src/Cedar/Protocol.c:5785]: (style) Variable 's' is assigned a value that is never used.
[src/Cedar/Protocol.c:6164]: (style) The function 'SocksConnectEx' is never used.
[src/Cedar/Protocol.c:907]: (style) The function 'CompareNodeInfo' is never used.
[src/Cedar/Protocol.c:6968]: (style) The function 'ProxyConnect' is never used.
[src/Cedar/Protocol.c:3986]: (style) The function 'SecureDelete' is never used.
[src/Cedar/Protocol.c:4042]: (style) The function 'SecureEnum' is never used.
[src/Cedar/Protocol.c:4127]: (style) The function 'SecureWrite' is never used.
[src/Cedar/Protocol.c:6463]: (style) The function 'SocksConnect' is never used.
[src/Cedar/Protocol.c:7185]: (style) The function 'TcpConnectEx2' is never used.
[src/Cedar/Protocol.c:7206]: (style) The function 'TcpIpConnect' is never used.
1.0.0.1 is a real IP address, owned by CloudFlare and used for their DNS service.
This commit changes the IP address we push to 192.0.0.8, which is defined in RFC7600 as dummy IPv4 address.
found by PVS analyzer
src/Mayaqua/Network.c 18715 err V571 Recurring check. The 'if (u->GetNatTIpThread == NULL)' condition was already verified in line 18712.
found by cppcheck
[src/Mayaqua/OS.c:493]: (style) The function 'OSDec32' is never used.
[src/Mayaqua/OS.c:373]: (style) The function 'OSDeleteDir' is never used.
[src/Mayaqua/OS.c:393]: (style) The function 'OSFileCreate' is never used.
[src/Mayaqua/OS.c:353]: (style) The function 'OSFileDelete' is never used.
[src/Mayaqua/OS.c:383]: (style) The function 'OSFileOpen' is never used.
[src/Mayaqua/OS.c:331]: (style) The function 'OSFileRename' is never used.
[src/Mayaqua/OS.c:487]: (style) The function 'OSInc32' is never used.
[src/Mayaqua/OS.c:363]: (style) The function 'OSMakeDir' is never used.
[src/Mayaqua/OS.c:541]: (style) The function 'OSResetEvent' is never used.
found by cppcheck
[src/Cedar/Proto_IkePacket.c:958]: (style) The function 'IkeNewCertPayload' is never used.
[src/Cedar/Proto_IkePacket.c:942]: (style) The function 'IkeNewCertRequestPayload' is never used.
[src/Cedar/Proto_IkePacket.c:875]: (style) The function 'IkeNewNoticeErrorInvalidExchangeTypePayload' is never used.
[src/Cedar/Proto_IkePacket.c:2542]: (style) The function 'IkeNewSpi' is never used.
[src/Cedar/Proto_IkePacket.c:142]: (style) The function 'IkePhase1CryptIdToKeySize' is never used.
[src/Cedar/Proto_IkePacket.c:157]: (style) The function 'IkePhase2CryptIdToKeySize' is never used.
[src/Cedar/Proto_IkePacket.c:172]: (style) The function 'IkeStrToPhase1CryptId' is never used.
[src/Cedar/Proto_IkePacket.c:187]: (style) The function 'IkeStrToPhase1HashId' is never used.
[src/Cedar/Proto_IkePacket.c:196]: (style) The function 'IkeStrToPhase2CryptId' is never used.
[src/Cedar/Proto_IkePacket.c:211]: (style) The function 'IkeStrToPhase2HashId' is never used.
[src/Cedar/Proto_IkePacket.c:2168]: (style) Condition 'b==NULL' is always true
This commit fixes the "TrackDeleteObj: 0x12345678 is not Object!!" (where 0x12345678 is the actual address) errors with memcheck enabled.
It also fixes the following related warnings:
warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
TrackChangeObjSize((DWORD)addr, size, (DWORD)new_addr);
^
warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
TrackChangeObjSize((DWORD)addr, size, (DWORD)new_addr);
^
1. ifdef DEBUG -> defined(_DEBUG) || defined(DEBUG)
In VC++ compilers, the macro is "_DEBUG", not "DEBUG".
2. If set memcheck = true, the program will be vitally slow since it will log all malloc() / realloc() / free() calls to find the cause of memory leak.
For normal debug we set memcheck = false.
Please set memcheck = true if you want to test the cause of memory leaks.
This commit improves the RecvFrom() and RecvFrom6() functions by:
- Using the right data type for the struct size variable passed to recvfrom().
- Improving the arguments validation mechanism.
- Printing unhandled errors.
- 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().
also cleanup a code based on PVS analyzer findings
src/Cedar/Hub.c 5279 warn V547 Expression 'e->UpdatedTime <= oldest_time' is always true.
src/Cedar/Hub.c 5840 warn V581 The conditional expressions of the 'if' statements situated alongside each other are identical. Check lines: 5828, 5840.
coverity thinks there might be null pointer dereference, make it
happier by removing check (there's a check against NULL in function itself).
condition "a.DataSize <= 1500" is always true
The previous regex expression removed all the 0s present in the input string, meaning that it caused the build to fail in case one of the date/time values was effectively 0.
found by coverity, cppcheck
[src/Cedar/Hub.c:6663]: (style) The function 'CalcTrafficEntryDiff' is never used.
[src/Cedar/Hub.c:3387]: (style) The function 'GetSessionByPtr' is never used.
[src/Cedar/Hub.c:3139]: (style) The function 'SetSessionFirstRedirectHttpUrl' is never used.
[src/Cedar/Hub.c:3912]: (style) The function 'VgsSetEmbTag' is never used.
[src/Cedar/Hub.c:3918]: (style) The function 'VgsSetUserAgentValue' is never used.
Pull request #294 added SHA-256, SHA-384, and SHA-512 support to the protocol, but part of it was removed in faee11ff09, because it caused a buffer over-read crash.
It also broke the MD5 implementation because the switch-case block didn't handle the type anymore.
This pull request fixes all the implementations and improves the IkeHMac() function by using the dedicated hashing functions.
found by coverity, cppcheck
[src/Cedar/Server.c:2899]: (style) Variable 'is_vgs_enabled' is assigned a value that is never used.
[src/Cedar/Server.c:3961]: (style) Variable 'id' is assigned a value that is never used.
[src/Cedar/Server.c:5723]: (style) Variable 'c' is assigned a value that is never used.
[src/Cedar/Server.c:5767]: (style) Variable 'num_connections_per_ip' is assigned a value that is never used.
[src/Cedar/Server.c:7327]: (style) Variable 'num' is assigned a value that is never used.
[src/Cedar/Server.c:8444]: (style) The function 'SiCallEnumHubBegin' is never used.
[src/Cedar/Server.c:8454]: (style) The function 'SiCallEnumHubEnd' is never used.
[src/Cedar/Server.c:9923]: (style) The function 'SiCallTaskAsyncBegin' is never used.
[src/Cedar/Server.c:9949]: (style) The function 'SiCallTaskAsyncEnd' is never used.
[src/Cedar/Server.c:10769]: (style) The function 'SiCheckCurrentRegion' is never used.
[src/Cedar/Server.c:2831]: (style) The function 'SiGetAzureEnable' is never used.
[src/Cedar/Server.c:208]: (style) The function 'SiGetServerNumUserObjects' is never used.
[src/Cedar/Server.c:2435]: (style) The function 'SiInitBridge' is never used.
[src/Cedar/Server.c:2540]: (style) The function 'SiTest' is never used.
[src/Cedar/Server.c:6707]: (style) The function 'StGetServer' is never used.
found by cppcheck
[src/Mayaqua/Kernel.c:1199]: (style) Variable 'new_thread' is assigned a value that is never used.
[src/Mayaqua/Kernel.c:385]: (style) The function 'DelThreadFromThreadList' is never used.
[src/Mayaqua/Kernel.c:1726]: (style) The function 'GetCurrentLocale' is never used.
[src/Mayaqua/Kernel.c:562]: (style) The function 'GetHomeDir' is never used.
[src/Mayaqua/Kernel.c:1644]: (style) The function 'GetSpanStr' is never used.
[src/Mayaqua/Kernel.c:1695]: (style) The function 'GetSpanStrEx' is never used.
[src/Mayaqua/Kernel.c:950]: (style) The function 'GetTimeStr64' is never used.
[src/Mayaqua/Kernel.c:909]: (style) The function 'GetTimeStrEx64' is never used.
[src/Mayaqua/Kernel.c:1924]: (style) The function 'System64ToTime' is never used.
[src/Mayaqua/Kernel.c:1900]: (style) The function 'TimeToSystem64' is never used.
[src/Mayaqua/Kernel.c:470]: (style) The function 'WaitAllThreadsWillBeStopped' is never used.
[src/Mayaqua/Kernel.c:1478]: (style) The function 'GetTimeStr' is never used.
found by coverity, cppcheck
[src/Cedar/Session.c:1856]: (style) The function 'CompareSession' is never used.
[src/Cedar/Session.c:2384]: (style) The function 'DebugPrintSessionKey' is never used.
[src/Cedar/Session.c:2102]: (style) The function 'GetSessionFromKey32' is never used.
remove unused variable
[src/Cedar/IPsec_IKE.c:4332] -> [src/Cedar/IPsec_IKE.c:4332]: (style) Same expression on both sides of '||'.
[src/Cedar/IPsec_IKE.c:1665]: (style) Variable 'zero' is assigned a value that is never used.
found by coverity, cppcheck
[src/Cedar/Cedar.c:1605]: (style) The function 'EnableDebugLog' is never used.
[src/Cedar/Cedar.c:858]: (style) The function 'GetUnestablishedConnections' is never used.
[src/Cedar/Cedar.c:652]: (style) The function 'InitHiddenPassword' is never used.
[src/Cedar/Cedar.c:633]: (style) The function 'IsHiddenPasswordChanged' is never used.
[src/Cedar/Cedar.c:393]: (style) The function 'IsInNoSsl' is never used.
[src/Cedar/Cedar.c:1785]: (style) The function 'IsLaterBuild' is never used.
found by coverity, cppcheck
[src/Cedar/Client.c:9094]: (style) Unused variable: i
[src/Cedar/Client.c:500] -> [src/Cedar/Client.c:503]: (style) Variable 'ret' is reassigned a value before the old one has been used.
found by coverity, cppcheck
[src/Mayaqua/Network.c:10599] -> [src/Mayaqua/Network.c:10603]: (style) Variable 'ret' is reassigned a value before the old one has been used.
[src/Mayaqua/Network.c:10611] -> [src/Mayaqua/Network.c:10615]: (style) Variable 'e' is reassigned a value before the old one has been used.
[src/Mayaqua/Network.c:12979]: (style) Variable 'disable_conditional_accept' is assigned a value that is never used.
[src/Mayaqua/Network.c:12167]: (style) Variable 's' is assigned a value that is never used.
[src/Mayaqua/Network.c:12319]: (style) Variable 's' is assigned a value that is never used.
[src/Mayaqua/Network.c:20660]: (style) The function 'HttpSendInvalidHostname' is never used.
[src/Mayaqua/Network.c:6640]: (style) The function 'IsNetworkPrefixAddress6' is never used.
[src/Mayaqua/Network.c:17593]: (style) The function 'ParseIpAndSubnetMask6' is never used.
[src/Mayaqua/Network.c:473]: (style) The function 'SetNatTLowPriority' is never used.
[src/Mayaqua/Network.c:14924]: (style) The function 'SetSocketSendRecvBufferSize' is never used.
[src/Mayaqua/Network.c:6249]: (style) The function 'Win32AcceptCheckCallback_Delay' is never used.
[src/Mayaqua/Network.c:6264]: (style) The function 'Win32Accept_XP' is never used.
[src/Mayaqua/Network.c:7467]: (style) The function 'Win32GetTcpTableList' is never used.
[src/Mayaqua/Network.c:9171]: (style) The function 'Win32NetworkTest' is never used.
[src/Mayaqua/Network.c:6581]: (style) The function 'GetHostAddress6' is never used.
[src/Mayaqua/Network.c:7468]: (style) The function 'Win32GetTcpTableListByAllocateAndGetTcpExTableFromStack' is never used.
[src/Mayaqua/Network.c:7384]: (style) The function 'Win32GetTcpTableListByGetExtendedTcpTable' is never used.
[src/Mayaqua/Network.c:7515]: (style) The function 'Win32GetTcpTableListByGetTcpTable' is never used.
[src/Mayaqua/Network.c:6758]: (style) The function 'IPNot6' is never used.
variables. Found by coverity, cppcheck
[src/Mayaqua/Unix.c:2559]: (style) Unused variable: status
[src/Mayaqua/Unix.c:181]: (style) Redundant condition: select!=NULL. 'select==NULL || (select!=NULL && (*select)(entry))' is equivalent to 'select==NULL || (*select)(entry)'
[src/Mayaqua/Unix.c:1297]: (style) The function 'UnixDaemon' is never used.
[src/Mayaqua/Unix.c:543]: (style) The function 'UnixGetDiskFreeW' is never used.
[src/Mayaqua/Unix.c:834]: (style) The function 'UnixRestoreThreadPriority' is never used.
[src/Mayaqua/Unix.c:816]: (style) The function 'UnixSetThreadPriorityHigh' is never used.
[src/Mayaqua/Unix.c:825]: (style) The function 'UnixSetThreadPriorityIdle' is never used.
[src/Mayaqua/Unix.c:807]: (style) The function 'UnixSetThreadPriorityLow' is never used.
[src/Mayaqua/Unix.c:2805]: (style) The function 'UnixWaitProcess' is never used.
found by coverity, cppcheck
[src/Cedar/Client.c:10486]: (style) The function 'CiFreeInnerVPNServer' is never used.
[src/Cedar/Client.c:10877]: (style) The function 'CiGetNumActiveSessions' is never used.
[src/Cedar/Client.c:2042]: (style) The function 'CiHasAccountSensitiveInformationFile' is never used.
[src/Cedar/Client.c:10469]: (style) The function 'CiNewInnerVPNServer' is never used.
[src/Cedar/Client.c:1128]: (style) The function 'CncGetSessionId' is never used.
[src/Cedar/Client.c:767]: (style) The function 'CncPasswordDlgHaltThread' is never used.
[src/Cedar/Client.c:10681]: (style) The function 'CompareInternetSetting' is never used.
[src/Cedar/Client.c:11060]: (style) The function 'CtGetClient' is never used.
[src/Cedar/Client.c:5128]: (style) The function 'InRpcClientNotify' is never used.
[src/Cedar/Client.c:4340]: (style) The function 'InRpcEnumObjectInSecure' is never used.
[src/Cedar/Client.c:5140]: (style) The function 'OutRpcClientNotify' is never used.
[src/Cedar/Client.c:5657]: (style) Condition 'reg_port!=0' is always false
[src/Cedar/Client.c:683]: (style) Variable 'ret' is assigned a value that is never used.
[src/Cedar/Client.c:725]: (style) Variable 'ret' is assigned a value that is never used.
[src/Cedar/Client.c:1013]: (style) Variable 'param' is assigned a value that is never used.
found by coverity, cppcheck
[src/Cedar/BridgeUnix.c:270] -> [src/Cedar/BridgeUnix.c:279]: (style) Variable 'ret' is reassigned a value before the old one has been used.
[src/Cedar/BridgeUnix.c:560] -> [src/Cedar/BridgeUnix.c:569]: (style) Variable 't' is reassigned a value before the old one has been used.
[src/Cedar/BridgeUnix.c:1528] -> [src/Cedar/BridgeUnix.c:1537]: (style) Variable 'ret' is reassigned a value before the old one has been used.
[src/Cedar/BridgeUnix.c:1278]: (style) Unused variable: c
[src/Cedar/BridgeUnix.c:1090]: (style) The function 'DlipAttachRequest' is never used.
found by coverity, cppcheck
[src/Cedar/Command.c:9378]: (style) Variable 'ret' is assigned a value that is never used.
[src/Cedar/Command.c:9999]: (style) The function 'CmdEvalNetworkAndSubnetMask6' is never used.
found by coverity, cppcheck
[src/Cedar/EtherLog.c:327]: (style) The function 'EcAddLicenseKey' is never used.
[src/Cedar/EtherLog.c:385]: (style) The function 'ElCheckLicense' is never used.
found by coverity, cppcheck
[src/Mayaqua/TcpIp.c:578]: (style) Variable 'tcp_size' is assigned a value that is never used.
[src/Mayaqua/TcpIp.c:1034]: (style) Variable 'has_vlan_tag' is assigned a value that is never used.
[src/Mayaqua/TcpIp.c:1996]: (style) Variable 'tcp_header_size' is assigned a value that is never used.
[src/Mayaqua/TcpIp.c:127]: (style) The function 'IcmpEchoSend' is never used.
[src/Mayaqua/TcpIp.c:2194]: (style) The function 'ParsePacketL2' is never used.
[src/Mayaqua/TcpIp.c:251]: (style) The function 'IcmpEchoSendBySocket' is never used.
found by cppcheck and coverity
[src/Cedar/Command.c:523] -> [src/Cedar/Command.c:532]: (style) Variable 'ok' is reassigned a value before the old one has been used.
[src/Cedar/Command.c:776]: (style) Variable 'tick2' is assigned a value that is never used.
[src/Cedar/Command.c:2244]: (style) Variable 'halt_timeout' is assigned a value that is never used.
[src/Cedar/Command.c:2246]: (style) Variable 'check_clock_seed' is assigned a value that is never used.
[src/Cedar/Command.c:2247]: (style) Variable 'halting' is assigned a value that is never used.
[src/Cedar/Command.c:6904]: (style) Unused variable: tmp
[src/Cedar/Command.c:12217]: (style) Variable 'packet_log' is assigned a value that is never used.
[src/Cedar/Command.c:20825]: (style) Variable 'ret' is assigned a value that is never used.
[src/Cedar/Command.c:20883]: (style) Variable 'ret' is assigned a value that is never used.
[src/Cedar/Command.c:20927]: (style) Variable 'ret' is assigned a value that is never used.
[src/Cedar/Command.c:10022]: (style) The function 'CmdEvalIpAndMask46' is never used.
[src/Cedar/Command.c:10109]: (style) The function 'CmdEvalNetworkAndSubnetMask46' is never used.
[src/Cedar/Command.c:23025]: (style) The function 'CmdPrintRow' is never used.
[src/Cedar/Command.c:167]: (style) The function 'InRpcTtResult' is never used.
[src/Cedar/Command.c:148]: (style) The function 'OutRpcTtResult' is never used.
The workaround was required for the "net30" topology because:
"There is a problem in your selection of --ifconfig endpoints [local=192.168.30.10, remote=192.168.30.1]. The local and remote VPN endpoints must exist within the same 255.255.255.252 subnet. This is a limitation of --dev tun when used with the TAP-WIN32 driver. Try 'openvpn --show-valid-subnets' option for more info."
See https://community.openvpn.net/openvpn/wiki/Topology for detailed info.
also, remove unused functions:
[src/Cedar/EtherLog.c:1377]: (style) The function 'ElFree' is never used.
[src/Cedar/EtherLog.c:1370]: (style) The function 'ElInit' is never used.
[src/Cedar/Logging.c:679]: (style) The function 'HubLog' is never used.
[src/Cedar/Logging.c:888]: (style) The function 'IPCLog' is never used.
[src/Cedar/Logging.c:295]: (style) The function 'PrintEraseFileList' is never used.
[src/Cedar/Logging.c:1025]: (style) The function 'SecLog' is never used.
[src/Cedar/Logging.c:622]: (style) The function 'ServerLog' is never used.
[src/Cedar/Logging.c:2273]: (style) The function 'SetLogDirName' is never used.
[src/Cedar/Logging.c:2293]: (style) The function 'SetLogPrefix' is never used.
[src/Cedar/Logging.c:997]: (style) The function 'WriteMultiLineLog' is never used.
[src/Cedar/Logging.c:918]: (style) The function 'WriteSecurityLog' is never used.
[src/Cedar/Logging.c:1018] -> [src/Cedar/Logging.c:1006]:
(warning) Either the condition 'src_session!=NULL' is redundant or there is possible null
pointer dereference: src_session.
[src/Cedar/Interop_OpenVPN.c:2711]: (style) Variable 'now' is assigned a value that is never used.
[src/Cedar/Interop_OpenVPN.c:1053]: (style) The function 'OvsAddEntry' is never used.
[src/Cedar/Interop_OpenVPN.c:2610]: (style) The function 'OvsGetCompatibleL3IPNext' is never used.
[src/Cedar/Interop_OpenVPN.c:1047]: (style) The function 'OvsNewList' is never used.
[src/Cedar/Interop_OpenVPN.c:128]: (style) The function 'OvsSetNoOpenVpnTcp' is never used.
[src/Cedar/Interop_OpenVPN.c:140]: (style) The function 'OvsSetNoOpenVpnUdp' is never used.
[src/Mayaqua/Str.c:3019]: (style) The function 'CopyFormat' is never used.
[src/Mayaqua/Str.c:280]: (style) The function 'HexToInt64' is never used.
[src/Mayaqua/Str.c:2448]: (style) The function 'InChar' is never used.
[src/Mayaqua/Str.c:745]: (style) The function 'IniHasValue' is never used.
[src/Mayaqua/Str.c:692]: (style) The function 'IniInt64Value' is never used.
[src/Mayaqua/Str.c:726]: (style) The function 'IniUniStrValue' is never used.
[src/Mayaqua/Str.c:2138]: (style) The function 'IsPrintableAsciiStr' is never used.
[src/Mayaqua/Str.c:1045]: (style) The function 'NormalizeCrlf' is never used.
[src/Mayaqua/Str.c:2899]: (style) The function 'ReplaceFormatStringFor64' is never used.
[src/Mayaqua/Str.c:2442]: (style) The function 'SearchStri' is never used.
[src/Mayaqua/Str.c:3345]: (style) The function 'StrCheckSize' is never used.
[src/Mayaqua/Str.c:1386]: (style) The function 'StrListToStr' is never used.
[src/Mayaqua/Str.c:348]: (style) The function 'ToHex64' is never used.
[src/Mayaqua/Str.c:2803]: (style) The function 'ToStri' is never used.
[src/Mayaqua/Str.c:2797]: (style) The function 'ToStrx' is never used.
[src/Mayaqua/Str.c:2791]: (style) The function 'ToStrx8' is never used.
[src/Mayaqua/Str.c:1325]: (style) The function 'TokenListToList' is never used.
OpenVPN sends the cipher name in uppercase, even if it's not standard, thus we have to convert it to lowercase for EVP_get_cipherbyname().
We also have to send the cipher name as it was received from the OpenVPN client, unless it's a different cipher, to prevent a message such as:
"WARNING: 'cipher' is used inconsistently, local='cipher AES-128-GCM', remote='cipher aes-128-gcm'"
It happens because OpenVPN uses "strcmp()" to compare the local and remote parameters: a6fd48ba36/src/openvpn/options.c (L3819-L3831)
See https://github.com/openssl/openssl/issues/6921 for EVP_get_cipherbyname().
