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# MSC2610: Remove `m.login.oauth2` User-Interactive Authentication type from the specification
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The client-server API specification
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[defines](https://matrix.org/docs/spec/client_server/r0.6.1#authentication-types)
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a number of "authentication types" for use with the User-Interactive
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Authentication protocol.
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Of these, `m.login.oauth2` is underspecified and of no
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real use. This MSC proposes removing them.
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## Proposal
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The definition of
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[OAuth2-based](https://matrix.org/docs/spec/client_server/r0.6.1#oauth2-based)
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authentication is incomplete. [OAuth2](https://oauth.net/2/) is best considered
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as a framework for implementing authentication protocols rather than a protocol
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in its own right, and this section says nothing about the grant types, flows
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and scopes which a compliant implementation should understand.
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A better candidate for OAuth2-based authentication of matrix clients is via
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[OpenID Connect](https://openid.net/connect/), but this has already been
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implemented in Matrix via the `m.login.sso` authentication type.
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The `m.login.oauth2` section is therefore unimplementable in its current form,
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and redundant. It should be removed from the specification to reduce confusion.
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## Alternatives
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It would be possible to extend the definition so that it is complete: as
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mentioned above, a likely implementation would be based on OpenID
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Connect. Matrix clients could then follow the standardised OpenID Connect flow
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rather than the matrix-specific `m.login.sso` flow. However, this would require
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significant design work, and development in both clients and servers, which
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currently feels hard to justify when a working solution exists via
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`m.login.sso`.
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