Function VerifyEmbeddedSignature

cppcryptfs/ui/certutil.cpp:38–213

#pragma comment (lib, "wintrust")

bool VerifyEmbeddedSignature(LPCWSTR pwszSourceFile)
{
	LONG lStatus;

	// Initialize the WINTRUST_FILE_INFO structure.

	WINTRUST_FILE_INFO FileData;
	memset(&FileData, 0, sizeof(FileData));
	FileData.cbStruct = sizeof(WINTRUST_FILE_INFO);
	FileData.pcwszFilePath = pwszSourceFile;
	FileData.hFile = NULL;
	FileData.pgKnownSubject = NULL;

	/*
	WVTPolicyGUID specifies the policy to apply on the file
	WINTRUST_ACTION_GENERIC_VERIFY_V2 policy checks:

	1) The certificate used to sign the file chains up to a root
	certificate located in the trusted root certificate store. This
	implies that the identity of the publisher has been verified by
	a certification authority.

	2) In cases where user interface is displayed (which this example
	does not do), WinVerifyTrust will check for whether the
	end entity certificate is stored in the trusted publisher store,
	implying that the user trusts content from this publisher.

	3) The end entity certificate has sufficient permission to sign
	code, as indicated by the presence of a code signing EKU or no
	EKU.
	*/

	GUID WVTPolicyGUID = WINTRUST_ACTION_GENERIC_VERIFY_V2;
	WINTRUST_DATA WinTrustData;

	// Initialize the WinVerifyTrust input data structure.

	// Default all fields to 0.
	memset(&WinTrustData, 0, sizeof(WinTrustData));

	WinTrustData.cbStruct = sizeof(WinTrustData);

	// Use default code signing EKU.
	WinTrustData.pPolicyCallbackData = NULL;

	// No data to pass to SIP.
	WinTrustData.pSIPClientData = NULL;

	// Disable WVT UI.
	WinTrustData.dwUIChoice = WTD_UI_NONE;

	// No revocation checking.
	WinTrustData.fdwRevocationChecks = WTD_REVOKE_NONE;

	// Verify an embedded signature on a file.
	WinTrustData.dwUnionChoice = WTD_CHOICE_FILE;

	// Verify action.