How can I validate digital signatures for Microsoft's Portable Executable format in portable code?
See the question and my original answer on StackOverflowYou could check at WINE's WinVerifyTrust implementation for a full programmatic way.
And, actually, here is a good link How to verify executable digital signatures under Linux? that complains about WINE implementation (that was back in 2008), and thus, explains the process in a quite "portable" way, provided you have something similar to OpenSSL available in your platform.