IObjectId::GetAlgorithmName method (certenroll.h)

The GetAlgorithmName method retrieves the display name associated with an algorithm object identifier (OID).

Syntax

HRESULT GetAlgorithmName(
  [in]  ObjectIdGroupId        GroupId,
  [in]  ObjectIdPublicKeyFlags KeyFlags,
  [out] BSTR                   *pstrAlgorithmName
);

Parameters

[in] GroupId

An ObjectIdGroupId enumeration value that specifies the OID group to search. This can be any of the following algorithm groups:

  • XCN_CRYPT_HASH_ALG_OID_GROUP_ID
  • XCN_CRYPT_ENCRYPT_ALG_OID_GROUP_ID
  • XCN_CRYPT_PUBKEY_ALG_OID_GROUP_ID
  • XCN_CRYPT_SIGN_ALG_OID_GROUP_ID
In addition, you can also specify groups that do not contain cryptographic algorithms:
  • XCN_CRYPT_RDN_ATTR_OID_GROUP_ID
  • XCN_CRYPT_EXT_OR_ATTR_OID_GROUP_ID
  • XCN_CRYPT_ENHKEY_USAGE_OID_GROUP_ID
  • XCN_CRYPT_POLICY_OID_GROUP_ID
  • XCN_CRYPT_TEMPLATE_OID_GROUP_ID

[in] KeyFlags

An ObjectIdPublicKeyFlags enumeration value that specifies whether to search for a signing or an encryption algorithm. This can be one of the following values:

  • XCN_CRYPT_OID_INFO_PUBKEY_ANY
  • XCN_CRYPT_OID_INFO_PUBKEY_SIGN_KEY_FLAG
  • XCN_CRYPT_OID_INFO_PUBKEY_ENCRYPT_KEY_FLAG
You can use either of the last two values to disambiguate among algorithms such as RSA that can be used to both encrypt and sign messages. You must also specify XCN_CRYPT_PUBKEY_ALG_OID_GROUP_ID in the GroupId parameter. Specify XCN_CRYPT_OID_INFO_PUBKEY_ANY if you set the GroupId parameter to anything other than XCN_CRYPT_PUBKEY_ALG_OID_GROUP_ID.

[out] pstrAlgorithmName

Pointer to a BSTR variable that contains the name.

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
CERTSRV_E_PROPERTY_EMPTY
The string that contains the algorithm name is empty.
OLE_E_BLANK
The algorithm name could not be found. You must call InitializeFromAlgorithmName before calling GetAlgorithmName.

Remarks

You can use the XCN_CRYPT_ENCRYPT_ALG_OID_GROUP_ID constant to create a GroupId parameter value that takes account of the key size for algorithms that can be identified by a variable bit length. For example, to initialize an IObjectId object from a 192-bit AES algorithm, specify "AES" for the strAlgorithmName parameter, shift the length left by 16, and perform a bitwise-OR combination on the shifted bit length and XCN_CRYPT_ENCRYPT_ALG_OID_GROUP_ID.

If you set the GroupId parameter to anything other than XCN_CRYPT_PUBKEY_ALG_OID_GROUP_ID, specify XCN_CRYPT_OID_INFO_PUBKEY_ANY for the KeyFlags parameter.

Requirements

   
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

IObjectId