Mission Lifecycle Signals for OAuth 2.0

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Table of Contents

1. Introduction

Mission-Bound Authorization for OAuth 2.0 [I-D.draft-mcguinness-oauth-mission] (the "issuance profile") gates derivation on Mission state and bounds outstanding self-contained tokens by their lifetime. The Mission Status and Lifecycle profile [I-D.draft-mcguinness-oauth-mission-status] adds surfaces for observing and changing state, and points to event-driven propagation for deployments that need Mission state changes to reach consumers promptly, without each consumer polling Mission Status per Mission. It does not define the channel.¶

This document defines the channel. When a Mission Issuer commits a Mission lifecycle transition (a revocation, expiry, suspension, completion, or the approval event that activates a Mission), it emits a Mission lifecycle-change Security Event Token (Section 4) over a profile of the OpenID Shared Signals Framework [OIDC-SSF]: pushed to a consumer's receiver [RFC8935] or made available for the consumer to poll [RFC8936], as a Security Event Token (SET) [RFC8417]. A consumer that receives a non-active transition stops honoring the Mission (Section 6). A deployment offers this channel by publishing the event stream (Section 3); consumers discover it from mission_event_stream_endpoint (Section 9).¶

This document is OPTIONAL and experimental: adopt it for evaluation, not as a stable interface. Push delivery is a propagation latency optimization over correctly sized pull: a consumer that polls the Status profile's surfaces within the deployment's published staleness bound, and fails safe on the Mission's expires_at, already meets the suite's revocation-propagation model without this channel ([I-D.draft-mcguinness-oauth-mission-status]). Deploy this profile where polling per Mission does not scale or the staleness bound must shrink below a practical polling interval.¶

This document defines no new Mission semantics: the Mission, its lifecycle states, and the mission claim are defined in [I-D.draft-mcguinness-oauth-mission]. The states this event reports are the issuance profile's lifecycle state space [I-D.draft-mcguinness-oauth-mission] as extended by whichever lifecycle profiles the deployment runs ([I-D.draft-mcguinness-oauth-mission-status] and any companion profile it adopts). A deployment that does not stand up an event stream uses the polling surfaces of the Status profile instead and is unaffected by this document.¶

2. Conventions and Terminology

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here.¶

This document uses the terms defined in the issuance profile [I-D.draft-mcguinness-oauth-mission] and the Status profile [I-D.draft-mcguinness-oauth-mission-status], in particular Mission, Mission Issuer (the Mission issuer: in this document's OAuth binding the Authorization Server; a standalone Mission Issuer, the Mission Authority Server [I-D.draft-mcguinness-mission-authority-server], transmits these events with the same semantics), mission_id, and the Mission lifecycle states. It additionally uses Security Event Token (SET) [RFC8417] and the Shared Signals Framework (SSF) [OIDC-SSF] transmitter, receiver, and stream terminology.¶

A consumer here is an SSF receiver that relies on Mission state, typically a Resource Server or an Authorization Server acting on a Mission it did not issue.¶

All JSON shown in this document is non-normative and illustrative; the member definitions in the surrounding text are authoritative. JWT and SET examples are shown as decoded JSON; on the wire the JWS Compact Serialization [RFC7515] applies.¶

3. Mission Lifecycle Event Stream

This section is OPTIONAL. A Mission Issuer that does not emit lifecycle events, and a consumer that does not receive them, are unaffected; they rely on token lifetime and the polling surfaces of [I-D.draft-mcguinness-oauth-mission-status].¶

A Mission Issuer that emits lifecycle events publishes a Shared Signals Framework [OIDC-SSF] stream and advertises it in Authorization Server metadata (Section 9) as mission_event_stream_endpoint. The endpoint and its configuration follow [OIDC-SSF]; this document profiles only the event carried, its protection, and the consumer's duty on receipt. The stream MUST be served over TLS 1.2 or later (TLS 1.3 RECOMMENDED), following the recommendations of [RFC9325].¶

Delivery uses the Shared Signals Framework delivery methods, advertised in the SSF Transmitter Configuration Metadata's delivery_methods_supported [OIDC-SSF]:¶

• push-based delivery, SET delivery method urn:ietf:rfc:8935 [RFC8935]: the Mission Issuer pushes SETs [RFC8417] to a consumer's registered receiver endpoint.¶

• poll-based delivery, SET delivery method urn:ietf:rfc:8936 [RFC8936]: the Mission Issuer makes SETs available for the consumer to poll.¶

A Mission Issuer that emits events MUST support at least one method, and a consumer discovers the supported methods from the SSF Transmitter Configuration Metadata rather than from a separate Authorization Server metadata member. The consumer's stream configuration declares, in its delivery object, the method it uses; the Mission Issuer MUST respect it and MUST NOT silently fall back to a less-timely method.¶

4. The Mission Lifecycle Change Event

A Mission Issuer emits a mission.lifecycle-change event, carried in the Security Event Token shape of the Shared Signals Framework [OIDC-SSF] and informed by the Continuous Access Evaluation Profile [OIDC-CAEP], when it commits any Mission lifecycle transition or the approval event that activates a Mission. The event type URI, defined in this document and described in Section 13, is:¶

https://schemas.karlmcguinness.com/mission/lifecycle-change¶

This URI is the registered event-type identifier; mission.lifecycle-change is the short name this document uses for it in prose.¶

The SET subject is the Mission, identified by a sub_id Subject Identifier [RFC9493] of format opaque whose id is the canonical mission_id ([I-D.draft-mcguinness-oauth-mission]), carried per Shared Signals Framework [OIDC-SSF] conventions. A receiver adds a Mission to its stream using this same subject identifier (Section 3).¶

The event is carried as the event-type-keyed value of the events claim of a SET [RFC8417], alongside the SET's own iss, aud, iat, jti, and sub_id. Its claims are:¶

• mission (object, required): the Mission identity, the same identity members as the mission object of [I-D.draft-mcguinness-oauth-mission-status], carrying id (the canonical Mission Identifier) and issuer (the Mission Issuer's issuer URL).¶

• state (string, required): the new lifecycle state. The value space is the Mission lifecycle state space defined by the issuance profile [I-D.draft-mcguinness-oauth-mission] (active, revoked, expired), as extended by whichever lifecycle profiles a deployment also runs: suspended and completed ([I-D.draft-mcguinness-oauth-mission-status]), superseded ([I-D.draft-mcguinness-oauth-mission-expansion]), and cascaded ([I-D.draft-mcguinness-oauth-mission-child-delegation]). Following the issuance profile's forward-compatibility rule, an event consumer MUST treat every value other than active as non-deriving, including a value it does not recognize. A Mission Issuer that runs a profile defining an additional state emits that state here on the corresponding transition (for example, superseded when a predecessor is superseded by an expansion successor).¶

• prior_state (string, conditional): the state immediately before the transition, drawn from the same value space. REQUIRED on a transition emission; absent only on the approval-event emission, where there is no prior state. A supersede transition emits prior_state of active and state of superseded.¶

• version (integer, required): a strictly monotonic per-Mission counter the Mission Issuer maintains and increments on each committed lifecycle transition (the approval-event emission is version 1), letting a consumer order events and detect gaps. This profile defines the counter here; it is not surfaced by the issuance or status profiles.¶

• committed_at (string, required): an RFC 3339 [RFC3339] date-time at which the Mission Issuer committed the transition.¶

• tenant (string, optional): the Mission's deployment tenant. This profile defines no tenant model and does not use it; it is present so the event type is shared, unchanged, with multi-tenant and cross-substrate deployments that do.¶

• reason (string, optional): a human-readable reason, for audit.¶

• successor (string, optional): the successor mission_id. Present only when state is superseded, giving the successor that replaced the Mission ([I-D.draft-mcguinness-oauth-mission-expansion]).¶

The expired event MAY be emitted lazily. Because expiry is driven by the clock reaching the Mission's expires_at rather than an explicit request, a Mission Issuer emits the expired event at or after the Mission's expires_at, when it observes the transition. A consumer does not depend on prompt emission: it already fails safe on the Mission's expires_at carried with cached Mission status ([I-D.draft-mcguinness-oauth-mission-status]).¶

Example SET (decoded), for a revocation:¶

{
  "iss": "https://as.example.com",
  "aud": "https://erp.example.com",
  "iat": 1793609600,
  "jti": "set_9Kp2vN7sR1tY8mZ3qX5b",
  "sub_id": {
    "format": "opaque",
    "id": "msn_8RfX2Lqv9TqMv4z7sA2bN1k0YpEdHc9-"
  },
  "events": {
    "https://schemas.karlmcguinness.com/mission/lifecycle-change": {
      "mission": {
        "id": "msn_8RfX2Lqv9TqMv4z7sA2bN1k0YpEdHc9-",
        "issuer": "https://as.example.com"
      },
      "prior_state": "active",
      "state": "revoked",
      "version": 2,
      "committed_at": "2026-11-02T09:06:40Z",
      "reason": "Quarterly reconcile completed early"
    }
  }
}

Example SET (decoded), for the approval event that activates the Mission (version 1, no prior_state):¶

{
  "iss": "https://as.example.com",
  "aud": "https://erp.example.com",
  "iat": 1793602800,
  "jti": "set_3Fw7bJ4nQ9xD2kM6vL1c",
  "sub_id": {
    "format": "opaque",
    "id": "msn_8RfX2Lqv9TqMv4z7sA2bN1k0YpEdHc9-"
  },
  "events": {
    "https://schemas.karlmcguinness.com/mission/lifecycle-change": {
      "mission": {
        "id": "msn_8RfX2Lqv9TqMv4z7sA2bN1k0YpEdHc9-",
        "issuer": "https://as.example.com"
      },
      "state": "active",
      "version": 1,
      "committed_at": "2026-11-02T07:00:00Z"
    }
  }
}

Example SET (decoded), for a supersession, carrying successor:¶

{
  "iss": "https://as.example.com",
  "aud": "https://erp.example.com",
  "iat": 1793612400,
  "jti": "set_6Tn4rW8pB3zK7qC2mV5j",
  "sub_id": {
    "format": "opaque",
    "id": "msn_8RfX2Lqv9TqMv4z7sA2bN1k0YpEdHc9-"
  },
  "events": {
    "https://schemas.karlmcguinness.com/mission/lifecycle-change": {
      "mission": {
        "id": "msn_8RfX2Lqv9TqMv4z7sA2bN1k0YpEdHc9-",
        "issuer": "https://as.example.com"
      },
      "prior_state": "active",
      "state": "superseded",
      "version": 2,
      "committed_at": "2026-11-02T09:40:00Z",
      "successor": "msn_2Yt7Qv9LqMv4z7sA2bN1k0YpEdHc9RfX"
    }
  }
}

5. SET Protection

Each SET [RFC8417] is a JWS Compact Serialization [RFC7515] signed with a Mission Issuer key resolvable in the issuer's jwks_uri, with a typ of secevent+jwt and a kid identifying the signing key. A consumer MUST verify the signature against the Mission Issuer's published keys and MUST refuse a SET whose iss does not match the Mission Issuer it registered with. Because this profile is single-issuer, the SET iss equals the event's mission.issuer; a consumer MAY treat a mismatch as a verification failure. (mission.issuer is carried in the event for cross-substrate deployments where the two can differ.)¶

The SET aud MUST be the receiving consumer's registered audience identifier; a consumer MUST refuse a SET whose aud is not its own. A consumer MUST treat jti as a one-time identifier and reject a replayed jti, tracking each jti for a deployment-defined replay window measured from the SET's iat. Following [RFC8417], this profile does not require an exp on the SET; a consumer MAY reject a SET whose iat is implausibly old.¶

6. Consumer Behavior on Receipt

On receiving and verifying (Section 5) a mission.lifecycle-change event, a consumer MUST:¶

• Stop honoring the affected Mission for any new consequential use when state is anything other than active: refuse to act on, and refuse to derive further authority from, tokens bound to that Mission ([I-D.draft-mcguinness-oauth-mission]), to the extent of the consumer's enforcement role.¶

• Resume honoring the Mission on a verified event whose state is active and whose version is greater than the last applied for that mission.id, subject to the same gating the issuance profile applies. This covers a reversible transition (for example a suspended Mission that is later resumed to active).¶

• Apply the transition idempotently: a repeated or out-of-order event carrying a version not greater than the last applied for that mission.id MUST NOT regress the consumer's view of the state.¶

• Acknowledge the event per the SSF delivery method in use.¶

A consumer MUST NOT treat the event as authority to change Mission state at the Mission Issuer; the Mission Issuer is authoritative ([I-D.draft-mcguinness-oauth-mission-status]). A consumer that believes the reported state is wrong re-checks through Mission Status rather than inventing a state.¶

A consumer anchors stream liveness to the Shared Signals Framework [OIDC-SSF] stream verification event. A consumer that cannot verify its stream, or that was down and may have missed events, SHOULD treat its cached Mission state as stale once it exceeds the Mission Issuer's advertised mission_max_stale_seconds ([I-D.draft-mcguinness-oauth-mission-status]) and SHOULD fall back to the Mission Status operation rather than continue on possibly stale state.¶

7. Relationship to Revocation Propagation

This document is the event-driven mechanism the Status profile's revocation-propagation guidance points to ([I-D.draft-mcguinness-oauth-mission-status]): a Mission Issuer that offers it emits mission.lifecycle-change events (Section 4) over the stream (Section 3), and consumers subscribe and apply Section 6. A deployment that offers event-driven propagation MUST advertise mission_event_stream_endpoint (Section 9) and support at least one SSF delivery method (Section 3), so consumers discover it.¶

This document neither requires nor presumes event-driven propagation; a Mission Issuer MAY emit lifecycle events for audit or operational purposes independent of any consumer's enforcement posture.¶

8. Worked Example

A partner ERP (erp.partner.example.com) consumes Mission lifecycle signals so it can stop honoring a Mission promptly rather than wait out token lifetimes. alice cancels her Q3 reconciliation Mission. The Mission Issuer commits the revoked transition and pushes a SET to the consumer's receiver ([RFC8935]). Decoded SET:¶

{
  "iss": "https://as.example.com",
  "aud": "https://erp.partner.example.com",
  "iat": 1793610000,
  "jti": "set_5kQ8mP2vR9nT",
  "sub_id": {
    "format": "opaque",
    "id": "msn_8RfX2Lqv9TqMv4z7sA2bN1k0YpEdHc9-"
  },
  "events": {
    "https://schemas.karlmcguinness.com/mission/lifecycle-change": {
      "mission": {
        "id": "msn_8RfX2Lqv9TqMv4z7sA2bN1k0YpEdHc9-",
        "issuer": "https://as.example.com"
      },
      "state": "revoked",
      "prior_state": "active",
      "version": 7,
      "committed_at": "2026-11-02T09:00:00Z",
      "reason": "user_cancelled"
    }
  }
}

The consumer verifies the SET signature, iss, aud, and jti, sees version 7 is newer than any state it holds, and records the Mission as revoked. Because revoked is non-active, the consumer stops relying on the Mission: the next attempt to use a token bound to msn_8RfX2Lqv9TqMv4z7sA2bN1k0YpEdHc9- is refused, seconds after the cancellation, well inside the token's remaining lifetime. Had a stale active event for an earlier version arrived afterward, the version counter would cause the consumer to ignore it rather than revive the Mission.¶

9. Authorization Server Metadata

A Mission Issuer that emits lifecycle events advertises the following in its Authorization Server metadata [RFC8414], in addition to the issuance-profile and Status-profile members it already publishes:¶

mission_event_stream_endpoint:

OPTIONAL. A string containing a URL. The Shared Signals Framework [OIDC-SSF] stream endpoint for Mission lifecycle events (Section 3). Present when the Mission Issuer emits events. The supported delivery methods are discovered from the SSF stream Transmitter Configuration Metadata's delivery_methods_supported, not from a separate metadata member.¶

10. Security Considerations

The security considerations of the issuance profile [I-D.draft-mcguinness-oauth-mission] and the Status profile [I-D.draft-mcguinness-oauth-mission-status] apply. This section covers threats specific to event propagation.¶

11. Privacy Considerations

A mission.lifecycle-change event discloses a Mission's identifier, state transitions, and timing to its receivers. A Mission Issuer MUST deliver events only to consumers authorized for the Mission and MUST scope each SET to a single consumer audience (Section 5), so a consumer never learns of Missions it is not party to. Event streams and their delivery logs record mission_id and consumer identity over time; deployments MUST treat them as Mission information-disclosure surfaces with the privacy posture of [I-D.draft-mcguinness-oauth-mission-status].¶

The OPTIONAL reason (Section 4) is useful operational context, but the reason for a transition can be more sensitive than the fact of it. Because each SET is audience-scoped to a single authorized consumer (Section 5), reason is disclosed only to a party already authorized for the Mission, not broadcast. Even so, a Mission Issuer SHOULD include in reason only what that consumer needs, keep sensitive specifics in its own audit log rather than in the event, and MAY omit reason entirely when even a minimal reason would disclose more than the consumer requires.¶

12. Conformance

This document is OPTIONAL. An implementation that claims it:¶

• as a Mission Issuer, emits a signed mission.lifecycle-change SET (Section 4, Section 5) on every committed Mission lifecycle transition, supports at least one SSF delivery method (Section 3), and advertises mission_event_stream_endpoint (Section 9);¶

• as a consumer, verifies and applies received events per Section 5 and Section 6.¶

An implementation that supports neither role is still a conforming issuance profile [I-D.draft-mcguinness-oauth-mission].¶

13. IANA Considerations

14. References

Acknowledgments

The author thanks the implementers and reviewers of the Mission-Bound Authorization work, and the OpenID Shared Signals and CAEP communities, for the foundations this profile builds on.¶

Author's Address