ICertPropertyRenewal::InitializeFromCertificateHash method (certenroll.h)

The InitializeFromCertificateHash method initializes the object from the new certificate.

Syntax

HRESULT InitializeFromCertificateHash(
  [in] VARIANT_BOOL MachineContext,
  [in] EncodingType Encoding,
  [in] BSTR         strCertificate
);

Parameters

[in] MachineContext

A VARIANT_BOOL value that indicates whether the certificate store is for the local computer or the current user. Specify VARIANT_TRUE for the computer and VARIANT_FALSE for the user.

[in] Encoding

An EncodingType enumeration value that specifies the type of Unicode encoding applied to the input string that contains the DER-encoded certificate.

[in] strCertificate

A BSTR variable that contains the DER-encoded certificate.

Beginning with Windows 7 and Windows Server 2008 R2, you can specify a certificate thumb print or serial number rather than an encoded certificate. Doing so causes the function to search the appropriate local stores for the matching certificate. Keep in mind the following points:

  • The BSTR must be an even number of hexadecimal digits.
  • Whitespace between hexadecimal pairs is ignored.
  • The Encoding parameter must be set to XCN_CRYPT_STRING_HEXRAW.
  • The MachineContext parameter determines whether the user or computer stores or both are searched.
  • If a private key is needed, only the personal and request stores are searched.
  • If a private key is not needed, the root and intermediate CA stores are also searched.

Return value

If the function succeeds, the function returns S_OK.

If the function fails, it returns an HRESULT value that indicates the error. Possible values include, but are not limited to, those in the following table. For a list of common error codes, see Common HRESULT Values.

Return code/value Description
HRESULT_FROM_WIN32(ERROR_ALREADY_INITIALIZED)
The object is already initialized.

Remarks

This method creates a SHA-1 hash by using the specified certificate. The certificate must be encoded by using Distinguished Encoding Rules (DER) as defined by the Abstract Syntax Notation One (ASN.1) standard. You must also specify the type of Unicode encoding applied to the string that contains the DER-encoded certificate.

Typically the ICertPropertyRenewal object is initialized during the enrollment process. You can retrieve the certificate used during enrollment by calling the Certificate property on the IX509Enrollment interface.

Call the SetValueOnCertificate method to associate the property with a certificate. Call the Renewal property to retrieve the hash.

Requirements

Requirement Value
Minimum supported client Windows Vista [desktop apps only]
Minimum supported server Windows Server 2008 [desktop apps only]
Target Platform Windows
Header certenroll.h
DLL CertEnroll.dll

See also

ICertPropertyRenewal