I'm writing a function for an installer DLL to verify the Authenticode signature of EXE files already installed on the system.
The function needs to:
A) verify that the signature is valid.
B) verify that the signer is our organization.
Because this is in an installer, and because this needs to run on older Win2k installations, I don't want to rely on CAPICOM.dll, as it may not be on the target system.
The WinVerifyTrust API works great to solve (A).
I need to find a way to compare a known certificate (or properties therein) to the one that signed the EXE in question.
You should use CryptQueryObject.
This KB-article demonstrates the use: How To Get Information from Authenticode Signed Executables.
To the commenter that asked about how to do it without the Windows-APIs, I am not aware of any library that can do it, but the format is documented here: Windows Authenticode Portable Executable Signature Format
If the signature is valid, its certificate chain will contain your certificate. CertGetCertificateChain will get that chain.
来源：https://stackoverflow.com/questions/301024/validate-authenticode-signature-on-exe-c-without-capicom