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
- 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().
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.
