Network Working Group M. Ansari, Ed.
Internet-Draft Cisco
Intended status: Standards Track P. Hunt
Expires: September 10, 2015 Oracle
March 9, 2015
SCIM Soft Delete
draft-ansari-scim-soft-delete-00
Abstract
The System for Cross-Domain Identity Management (SCIM) specification
is an HTTP based protocol that makes managing identities in multi-
domain scenarios easier to support through a standardized HTTP
service.
Among other operations, SCIM defines delete operation where upon
successful completion of the call, the SCIM endpoint is supposed to
delete the requested object and the object should not be available
for future SCIM calls and not used in uniqueness criteria
requirements.
While this model is sufficient for a number of SCIM implementations,
there are cases this simple definition of delete may not meet product
or business requirements. For example a service provider may require
a user object to continue to exist as other objects/data is linked
with it or for billing purposes, etc. For example a cloud file
storage mechanism may require to show basic information about who
created a given file or modified one even if the user is de-
provisioned from the system.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on September 10, 2015.
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Copyright Notice
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Table of Contents
1. Introduction and Overview . . . . . . . . . . . . . . . . . . 2
1.1. Notational Conventions . . . . . . . . . . . . . . . . . 3
1.2. Definitions . . . . . . . . . . . . . . . . . . . . . . . 4
2. Soft Delete . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.1. Soft Delete Schema Extension . . . . . . . . . . . . . . 4
2.2. ServiceProviderConfig Extension . . . . . . . . . . . . . 5
2.3. SCIM Create . . . . . . . . . . . . . . . . . . . . . . . 5
2.4. SCIM Retrieve . . . . . . . . . . . . . . . . . . . . . . 5
2.5. SCIM Modify . . . . . . . . . . . . . . . . . . . . . . . 5
2.6. SCIM Delete . . . . . . . . . . . . . . . . . . . . . . . 5
2.7. SCIM Bulk . . . . . . . . . . . . . . . . . . . . . . . . 6
2.8. SCIM Undelete . . . . . . . . . . . . . . . . . . . . . . 6
2.9. SCIM Hard Delete . . . . . . . . . . . . . . . . . . . . 6
3. Security Considerations . . . . . . . . . . . . . . . . . . . 6
4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 6
5. References . . . . . . . . . . . . . . . . . . . . . . . . . 7
5.1. Normative References . . . . . . . . . . . . . . . . . . 7
5.2. Informative References . . . . . . . . . . . . . . . . . 7
Appendix A. Contributors . . . . . . . . . . . . . . . . . . . . 7
Appendix B. Acknowledgments . . . . . . . . . . . . . . . . . . 7
Appendix C. Change Log . . . . . . . . . . . . . . . . . . . . . 7
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 7
1. Introduction and Overview
The System for Cross-Domain Identity Management (SCIM) specification
is an HTTP based protocol that makes managing identities in multi-
domain scenarios easier to support through a standardized HTTP
service.
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For some services, even after a resource has been "deleted" from the
identity system, there are many artifacts that remain in the
application/services layer that were created/touched by the deleted
user. Such objects need to remain connected to the deleted object
and provide basic information. For example if a user created a
document, post, event, even after the user is removed, other users of
the system may still interact with these objects and need to see who
created the object even if the user is no longer part of the system.
Another use case is to protect against accidental loss of references
in case of a mistaken "delete" of a resource. Once a resource is
removed from the identity system, all that resource's references to
any data type is lost given the id of the resource will not be
recycled. Recreating the same resource is not going to revive its id
and essentially creates a new instance with a new id.
While SCIM delete operation as defined in Section 3.6 of
[I-D.ietf-scim-api] allows a service provider to keep a resource
after deletion, it does not provide any additional guidance or
specification on how the "deleted" resource will be managed beyond
the initial delete in cases the service provider does not want to
permanently remove a resource.
This specification defines a set of extensions to SCIM API
[I-D.ietf-scim-api] to allow additional operations on resources that
have been soft deleted:
o Query for resources that have been soft deleted
o Hard delete a soft deleted resource
o Undelete a soft deleted resource
o Extension to the ServiceProviderConfig [I-D.ietf-scim-core-schema]
to allow discovery of softDelete extensions
1.1. Notational Conventions
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119]. These
keywords are capitalized when used to unambiguously specify
requirements of the protocol or application features and behavior
that affect the interoperability and security of implementations.
When these words are not capitalized, they are meant in their
natural-language sense.
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For purposes of readability examples are not URL encoded.
Implementers MUST percent encode URLs as described in Section 2.1 of
[RFC3986].
Throughout this documents all figures MAY contain spaces and extra
line-wrapping for readability and space limitations. Similarly, some
URI's contained within examples, have been shortened for space and
readability reasons.
1.2. Definitions
Soft Deleted Resources A SCIM resource that has been deleted using
standard SCIM DELETE operation
2. Soft Delete
A SCIM endpoint supporting Soft Delete extensions MUST implement SCIM
DELETE operation in such a way that the resource being deleted is not
permanently deleted and stored in an alternate "soft deleted" state.
Other standard SCIM operations will continue to function as if soft
deleted resources do not exist in the system. READ, MODIFY, PATCH,
BULK requests with the soft deleted resource id MUST result in a HTTP
NOT FOUND (404). A create request for a user resource with a
userName that has been soft deleted, MUST NOT fail with an HTTP
status 409 due to the userName conflict with the soft deleted record.
2.1. Soft Delete Schema Extension
Any SCIM resource type that supports soft delete extensions MUST
extend the schema of the resource type by adding the extension
defined in this section.
The following Singular Attributes are defined:
isSoftDeleted
A Boolean attribute set to "true" for any resource that is soft
deleted. No value or "false" means the resource is not soft
deleted. This attribute has mutability of "readOnly"
softDeleted
A DateTime attribute set to the time the resource was softDeleted.
This attribute has mutability of "readOnly". This attribute
should be deleted once a resource is not in soft delete state.
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2.2. ServiceProviderConfig Extension
SCIM endpoints that support Soft Delete extensions MUST advertise
this support in the ServiceProviderConfig endpoint as defined:
softDelete
A complex type that specifies Soft Delete configuration options.
REQUIRED.
supported Boolean value specifying whether the operation is
supported. REQUIRED.
2.3. SCIM Create
SCIM Create SHOULD NOT ignore namespace conflicts arising from soft
deleted objects. For example if there exists a user resource with
userName value of "user1" that have been soft deleted, a create
request for userName with the same value should not fail because of
userName conflict.
2.4. SCIM Retrieve
SCIM retrieve operations MUST NOT match soft deleted objects unless
the request includes a filter with the value of "isSoftDeleted=true".
This is the only case where a soft deleted resource can be returned
as a result of a retrieve operation.
2.5. SCIM Modify
SCIM modify operation on resources that have been soft deleted MUST
result in a HTTP NOT FOUND 404.
2.6. SCIM Delete
SCIM Delete operations on normal resources MUST NOT remove the
resource, but put it in the soft deleted state by modifying the
resource and setting isSoftDeleted attribute on the resource to
"true" and setting the softDeleted timestamp value to the time of the
delete operation.
Delete operations on soft deleted resource MUST result in an HTTP NOT
FOUND 404 error.
[ToDo]Define reference semantics as resources are soft deleted
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2.7. SCIM Bulk
SCIM Bulk operations should follow the semantics defined in this
section for regular SCIM operations.error.
2.8. SCIM Undelete
To allow soft deleted resources to be restored to regular state, a
SCIM modify operations can be performed with a query parameter of
"isSoftDeleted=true" on the resource. The SCIM Endpoint MUST change
the state of the resource to reflect the change from soft deleted
state back to normal by removing the softDeleted attribute from the
resource and setting the isSoftDeleted attribute value to "false".
Furthermore if the process of undeleting the resource results in a
namespace conflict, the operation MUST fail and return an HTTP Status
409, with "scimType" error code of "uniqueness".
The SCIM client can optionally provide new attribute values as part
of the modify request to resolve the conflicts. For example to
undelete a user resource where the userName has been recycled, a
modify with a new userName value can be sent to the SCIM endpoint to
undelete the user resource by setting the value of userName to the
new value to avoid the conflict case.
2.9. SCIM Hard Delete
A soft deleted resource can be permanently deleted by sending a SCIM
Delete request with a query parameter of "isSoftDeleted=true". This
SCIM endpoint SHOULD permanently remove the resource.
3. Security Considerations
Soft deleted users MUST NOT be allowed to authenticate to the service
provider or access any resources. Furthermore soft deleted resources
SHOULD NOT be used in authorization decision and act as if those
resources do not exist.
[TO BE COMPLETED]
4. IANA Considerations
[TO BE COMPLETED]
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5. References
5.1. Normative References
[I-D.ietf-scim-api]
Hunt, P., Grizzle, K., Ansari, M., Wahlstroem, E., and C.
Mortimore, "System for Cross-Domain Identity Management:
Protocol", draft-ietf-scim-api-16 (work in progress),
March 2015.
[I-D.ietf-scim-core-schema]
Hunt, P., Grizzle, K., Wahlstroem, E., and C. Mortimore,
"System for Cross-Domain Identity Management: Core
Schema", draft-ietf-scim-core-schema-17 (work in
progress), March 2015.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC3986] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
Resource Identifier (URI): Generic Syntax", STD 66, RFC
3986, January 2005.
5.2. Informative References
[I-D.ietf-scim-use-cases]
Hunt, P., Khasnabish, B., Nadalin, A., Li, K., and Z.
Zeltsan, "SCIM Use Cases", draft-ietf-scim-use-cases-04
(work in progress), March 2015.
Appendix A. Contributors
Appendix B. Acknowledgments
The editor would like to thank the participants in the the SCIM
working group for their support of this specification.
Appendix C. Change Log
Draft 00 - MA - First Draft
Authors' Addresses
Morteza Ansari (editor)
Cisco Corporation
Email: morteza.ansari@cisco.com
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Phil Hunt
Oracle Corporation
Email: phil.hunt@yahoo.com
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