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c++cryptoapitrusted-timestamp

Crypto API - CryptRetrieveTimeStamp

Good day,

Can someone please help me using the Crypto Api function, CryptRetrieveTimeStamp? I successfully use CryptSignMessage to sign my message and now I want to timestamp the data at a TSA, but CryptRetrieveTimeStamp always return *TRUST_E_TIME_STAMP* error.

My function looks as follows, pbMessage and cbMessage are the data and size received from CryptSignMessage:

PCRYPT_TIMESTAMP_CONTEXT tcontext = NULL;
HCERTSTORE hStore = NULL;


fReturn = CryptRetrieveTimeStamp(widestr.c_str(),
       TIMESTAMP_NO_AUTH_RETRIEVAL, 
       0, 
       szOID_RSA_MD5, 
       NULL, 
       (const BYTE*)pbMessage, 
       cbMessage, 
       &tcontext, 
       NULL, 
       &hStore);

I know the error means: The time stamp signer and or certificate could not be verified or is malformed. But I have no idea what or how to solve this error?

Any help/hints would be appreciated. Thanks, Magda

Solution

  • Viewing the request/response through wireshark gave better insight into the problem.

    The TSA is a valid TSA, but the encoding was wrong. Changing *szOID_RSA_MD5* to *szOID_NIST_sha256* solved my problem.