fix: set JWK use=jwt-svid in JWKS (JWT-SVID §4)#101
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safayavatsal wants to merge 4 commits intohighflame-ai:mainfrom
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fix: set JWK use=jwt-svid in JWKS (JWT-SVID §4)#101safayavatsal wants to merge 4 commits intohighflame-ai:mainfrom
safayavatsal wants to merge 4 commits intohighflame-ai:mainfrom
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Conformant SPIFFE verifiers reject bundles where the published JWKs don't carry use=jwt-svid. We were emitting use=sig (RFC 7517 generic), which broke JWT-SVID interop with any standard SPIFFE workload client. Updates the regression assertion in wellknown_test.go to match. Fixes highflame-ai#43
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This pull request updates the JWKS key usage from "sig" to "jwt-svid" in internal/signing/jwks.go to comply with JWT-SVID §4 and SPIFFE verifier requirements. Corresponding integration tests in tests/integration/wellknown_test.go have been updated to reflect this change. I have no feedback to provide.
The first attempt (flipping use= directly in addToKeySet) broke our own introspection path: lestrrat-go/jwx's verifier filters out any key whose use is set to anything other than "sig" (jws/key_provider.go:113), so the in-memory keyset became unusable for signature verification. Split the concern: keep use=sig in the in-memory keyset (so jwx-based verifiers, including our internal introspection, still work) and rewrite use to "jwt-svid" only at the JWKS handler boundary. The published bundle is now spec-compliant for SPIFFE clients. Also normalize use=jwt-svid → sig on ingest in pkg/authjwt's JWKS refresh, so authjwt-based consumers keep working against the new bundle. Fixes highflame-ai#43
rsharath
approved these changes
May 5, 2026
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Summary
use=jwt-svidon every JWK at/.well-known/jwks.jsonper JWT-SVID §4.useinaddToKeySetdirectly. That broke our own introspection path:lestrrat-go/jwx's verifier (jws/key_provider.go:113) skips keys whoseuseis anything other than"sig", so the in-memory keyset stopped verifying signatures.use=sigin the in-memory keyset (jwx-based verifiers, including our/oauth2/token/introspect, keep working) and rewriteuseto"jwt-svid"at the JWKS handler boundary only.use=jwt-svid → sigon ingest inpkg/authjwt's JWKS refresh so authjwt-based consumers keep working against the new bundle.tests/integration/wellknown_test.go.Fixes #43
Test plan
go vet ./...cleango build ./...cleanmake testpasses (TestJWKSEndpointassertsuse=jwt-svid;TestAuthjwtVerifiesZeroIDTokenandTestAuthjwtAcceptsDefaultedAudienceconfirm authjwt still works against the new bundle)curl http://localhost:8899/.well-known/jwks.json | jq '.keys[].use'returns"jwt-svid"for both keys