<!--
{
  "documentType" : "article",
  "framework" : "GSS",
  "identifier" : "/documentation/GSS/object-identifiers",
  "metadataVersion" : "0.1.0",
  "role" : "collectionGroup",
  "title" : "Object Identifiers"
}
-->

# Object Identifiers

Store security mechanisms, QOPs (Quality of Protection values), and name types.

## Topics

### Object IDs

[`gss_OID`](/documentation/GSS/gss_OID)

A pointer to the OID descriptor that exchanges object identifiers with many GSS-API functions.

[`gss_OID_set`](/documentation/GSS/gss_OID_set)

A pointer to a descriptor that manages an array of OID descriptors.

[`gss_OID_desc`](/documentation/GSS/gss_OID_desc)

The OID descriptor that exchanges object identifiers with many GSS-API functions.

[`gss_const_OID`](/documentation/GSS/gss_const_OID)

A pointer to an immutable OID descriptor exchanges object identifiers with many GSS-API functions.

[`gss_const_OID_set`](/documentation/GSS/gss_const_OID_set)

A pointer to an immutable descriptor manages an array of OID descriptors.

[`gss_OID_desc_struct`](/documentation/GSS/gss_OID_desc_struct)

The structure for an OID descriptor that exchanges object identifiers with many GSS-API functions.

[`gss_OID_set_desc`](/documentation/GSS/gss_OID_set_desc)

The descriptor that manages an array of OID descriptors.

[`gss_OID_set_desc_struct`](/documentation/GSS/gss_OID_set_desc_struct)

The structure for an OID set descriptor that manages an array of OID descriptors.

### Quality of Protection Constants

[`GSS_C_QOP_DEFAULT`](/documentation/GSS/GSS_C_QOP_DEFAULT)

The default Quality of Protection for per-message services.

[`GSS_KRB5_CONF_C_QOP_DES`](/documentation/GSS/GSS_KRB5_CONF_C_QOP_DES)

The Kerberos 5 Qualty of Service 56-bit DES encryption.

[`GSS_KRB5_CONF_C_QOP_DES3_KD`](/documentation/GSS/GSS_KRB5_CONF_C_QOP_DES3_KD)

The Kerberos 5 Qualty of Service 168-bit DES3 encryption with key derivation.

### Creation and Release

[`gss_create_empty_oid_set`](/documentation/GSS/gss_create_empty_oid_set(_:_:))

Allocates a new, empty set to hold object identifiers.

[`gss_add_oid_set_member`](/documentation/GSS/gss_add_oid_set_member(_:_:_:))

Adds an object identifier into an OID set.

[`gss_release_oid_set`](/documentation/GSS/gss_release_oid_set(_:_:))

Releases the memory associated with an OID set.

[`gss_release_oid`](/documentation/GSS/gss_release_oid(_:_:))

Releases the memory associated with an object identifier.

### Conversion and Duplication

[`gss_oid_to_str`](/documentation/GSS/gss_oid_to_str(_:_:_:))

Converts an OID object to a human-readable string.

[`gss_test_oid_set_member`](/documentation/GSS/gss_test_oid_set_member(_:_:_:_:))

Returns a flag that indicates if an OID is present in an OID set.

[`gss_oid_equal`](/documentation/GSS/gss_oid_equal(_:_:))

Returns a flag that indicates whether two object identifiers are the same.

[`gss_duplicate_oid`](/documentation/GSS/gss_duplicate_oid(_:_:_:))

Copies an OID into a new object.


---

Copyright &copy; 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)