CRYPT_OID_INFO structure (wincrypt.h)

The CRYPT_OID_INFO structure contains information about an object identifier (OID). These structures give the relationship among an OID identifier, its name, its group, and other information about the OID. These structures can be listed by using the CryptEnumOIDInfo function. New CRYPT_OID_STRUCTURES can be added by using the CryptRegisterOIDInfo function.

Syntax

typedef struct _CRYPT_OID_INFO {
  DWORD           cbSize;
  LPCSTR          pszOID;
  LPCWSTR         pwszName;
  DWORD           dwGroupId;
  union {
    DWORD  dwValue;
    ALG_ID Algid;
    DWORD  dwLength;
  } DUMMYUNIONNAME;
  CRYPT_DATA_BLOB ExtraInfo;
  LPCWSTR         pwszCNGAlgid;
  LPCWSTR         pwszCNGExtraAlgid;
} CRYPT_OID_INFO, *PCRYPT_OID_INFO;

Members

cbSize

The size, in bytes, of this structure.

pszOID

The OID associated with this OID information.

pwszName

The display name associated with an OID.

dwGroupId

The group identifier value associated with this OID information.

This member can be one of the following dwGroupId group identifiers.

DUMMYUNIONNAME

DUMMYUNIONNAME.dwValue

A numeric value associated with this OID information. This member is used with dwGroupId CRYPT_SIGN_ALG_OID_GROUP_ID.

DUMMYUNIONNAME.Algid

The algorithm identifier associated with this OID information.

This member applies for the following values of dwGroupId:

• CRYPT_HASH_ALG_OID_GROUP_ID
• CRYPT_ENCRYPT_ALG_OID_GROUP_ID
• CRYPT_PUBKEY_ALG_OID_GROUP_ID
• CRYPT_SIGN_ALG_OID_GROUP_ID

DUMMYUNIONNAME.dwLength

This member is not implemented. It is always set to zero.

ExtraInfo

Extra information used to find or register OID information. This member applies for the following values of dwGroupId:

• CRYPT_PUBKEY_ALG_OID_GROUP_ID
• CRYPT_SIGN_ALG_OID_GROUP_ID
• CRYPT_RDN_ATTR_OID_GROUP_ID

The OIDs in the CRYPT_ENCRYPT_ALG_OID_GROUP_ID OID group have a bit length set for the AES algorithms in the DWORD[0] member of the ExtraInfo member.

The OIDs in the CRYPT_PUBKEY_ALG_OID_GROUP_ID group have a flag set in the DWORD[0] member of the ExtraInfo member.

The OIDs in the ECC curve name public keys, for example, szOID_ECC_CURVE_P256 ("1.2.840.10045.3.1.7"), have a flag set in the DWORD[0] member, a BCRYPT_ECCKEY_BLOB dwMagic field value set in the DWORD[1] member, and a bit length where the BCRYPT_ECCKEY_BLOB cbKey value equals dwBitLength / 8 + ((dwBitLength % 8) ? 1 : 0) set in the DWORD[2] member of the ExtraInfo member.

The OIDs in the CRYPT_SIGN_ALG_OID_GROUP_ID group have a public key algorithm identifier set in the DWORD[0] member, a flag set in the DWORD[1] member, and an optional provider type set in the DWORD[2] member of the ExtraInfo member.

The OIDs in the CRYPT_RDN_ATTR_OID_GROUP_ID group have a null-terminated list of acceptable RDN attribute value types set in an array of DWORD values in the ExtraInfo member. An omitted list implies an array of values where the first value in the array is CERT_RDN_PRINTABLE_STRING, the second value in the array is CERT_RDN_UNICODE_STRING, and the third value in the array is zero.

The following values are used for the flags in the ExtraInfo member.

Post-quantum use

CRYPT_PUBKEY_ALG_OID_GROUP_ID has the following ExtraInfo fields when used with PQ OIDs (above):

CRYPT_SIGN_ALG_OID_GROUP_ID has the following ExtraInfo fields when used with PQ OIDs:

CRYPT_HASH_ALG_OID_GROUP_ID can be set to L”NoHash” to indicate no hash before signing, and the PQ key will directly sign the ToBeSigned bytes.

pwszCNGAlgid

The algorithm identifier string passed to the CNG functions (the BCrypt* and NCrypt* functions that are defined in Bcrypt.h and Ncrypt.h). CNG functions use algorithm identifier strings, such as L"SHA1", instead of the ALG_ID data type constants, such as CALG_SHA1. Windows Server 2003 and Windows XP: This member is not available.

#define CRYPT_OID_INFO_HAS_EXTRA_FIELDS

This member applies for the following values of dwGroupId:

• CRYPT_HASH_ALG_OID_GROUP_ID
• CRYPT_ENCRYPT_ALG_OID_GROUP_ID
• CRYPT_PUBKEY_ALG_OID_GROUP_ID
• CRYPT_SIGN_ALG_OID_GROUP_ID

Set the pwszCNGAlgid member to the empty string, L"", for the other values of dwGroupId.

The pwszCNGAlgid member can also be set to a string value that is not passed directly to the CNG functions. The following table lists these values and their meanings:

pwszCNGExtraAlgid

An extra algorithm string, other than the string in the pwszCNGAlgid member, that can be passed to the CNG functions (the BCrypt* and NCrypt* functions that are defined in Bcrypt.h and Ncrypt.h).

Windows Server 2003 and Windows XP:  This member is not available.

#define CRYPT_OID_INFO_HAS_EXTRA_FIELDS

For the signature algorithms (CRYPT_SIGN_ALG_OID_GROUP_ID), this member is the public key algorithm string to pass to the CNG functions.

For ECC signatures, this member is the special CRYPT_OID_INFO_ECC_PARAMETERS_ALGORITHM string value.

For unsigned signatures, this member is the special CRYPT_OID_INFO_NO_SIGN_ALGORITHM string value.

For ECC curve name public keys, for example, szOID_ECC_CURVE_P256 ("1.2.840.10045.3.1.7"), this is the special CRYPT_OID_INFO_ECC_PARAMETERS_ALGORITHM string value.

For the other values of dwGroupId, set the pwszCNGExtraAlgid member to the empty string, L"".

Requirements

See also

CryptFindOIDInfo

CryptRegisterOIDInfo

CryptUnregisterOIDInfo