CertGetIssuerCertificateFromStore

A version of this page is also available for

Windows Embedded CE 6.0 R3

4/8/2010

This function retrieves the certificate context from the certificate store for the first or next issuer of the specified subject certificate. The new certificate chain verification functions are recommended instead of the use of this function.

Syntax

PCCERT_CONTEXT WINAPI CertGetIssuerCertificateFromStore(
  HCERTSTORE hCertStore,
  PCCERT_CONTEXT pSubjectContext,
  PCCERT_CONTEXT pPrevIssuerContext,
  DWORD* pdwFlags
);

Parameters

• hCertStore
  [in] Handle to a certificate store.

• pSubjectContext
  [in] Pointer to a CERT_CONTEXT structure containing the subject information. This parameter can be obtained from any certificate store or can be created by the calling application using the CertCreateCertificateContext function.

• pPrevIssuerContext
  [in] Optional. Pointer to a CERT_CONTEXT structure containing the issuer information. An issuer can have multiple certificates, especially when a validity period is about to change. This parameter must be NULL on the call to get the first issuer certificate. To get the next certificate for the issuer, set the pPrevIssuerContext parameter to the CERT_CONTEXT structure returned by the previous call.

  A pPrevIssuerContext parameter that is not NULL is always freed by the CertGetIssuerCertificateFromStore function by using the CertFreeCertificateContext function, even for an error.

• pdwFlags
  [in, out] On input, flags that enable verification checks on the returned certificate. The flags can be combined using a bitwise OR operation to enable multiple verifications. The following table shows the flags for this parameter.

  Value	Description
  CERT_STORE_NO_CRL_FLAG	Indicates no matching CRL was found.
  CERT_STORE_NO_ISSUER_FLAG	Indicates no issuer certificate was found.
  CERT_STORE_SIGNATURE_FLAG	Uses the public key in the issuer's certificate to verify the signature on the subject certificate.
  CERT_STORE_TIME_VALIDITY_FLAG	Gets the current time and verifies that it is within the subject certificate's validity period.

  On output, if a verification check of an enabled type succeeds, its flag is set to zero. If it fails, the value of the flag is not changed.

  In the case of a verification check failure, a pointer to the issuer's CERT_CONTEXT structure is still returned and the GetLastError function is not updated.

Return Value

If the function succeeds, the return value is a pointer to a read-only issuer CERT_CONTEXT structure.

If the function fails and the first or next issuer certificate is not found, the return value is NULL.

Only the last returned CERT_CONTEXT structure must be freed by calling the CertFreeCertificateContext function. When the returned CERT_CONTEXT structure from one call to the function is supplied as the pPrevIssuerContext parameter on a subsequent call, the context is freed as part of the action of the function.

For extended error information, call the GetLastError function. The following table shows some possible error codes.

Remarks

The CertDuplicateCertificateContext function can be called to make a duplicate of the issuer certificate.

The hexadecimal values for the pdwFlags parameter can be combined using a bitwise OR operation to enable multiple verifications. For example, to enable both signature and time validity, the value 0x00000003 is passed in the pdwFlags parameter on input. In this case, if CERT_STORE_SIGNATURE_FLAG verification succeeds but CERT_STORE_TIME_VALIDITY_FLAG verification fails, the pdwFlags parameter returns as 0x00000002 on output.

The desktop operating system supports the CERT_STORE_REVOCATION_FLAG value for the pdwFlags parameter; that Windows Embedded CE does not.

Requirements

See Also

Reference

CertCreateCertificateContext
CertFreeCertificateContext
CertDuplicateCertificateContext
CERT_CONTEXT