feat: add JWKS Cache management for use in non-persistent runtimes

docs/README.md

@@ -32,6 +32,8 @@ Support from the community to continue maintaining and improving this module is
 - [enableDecryptingResponses](functions/enableDecryptingResponses.md)
 - [enableDetachedSignatureResponseChecks](functions/enableDetachedSignatureResponseChecks.md)
 - [enableNonRepudiationChecks](functions/enableNonRepudiationChecks.md)
+- [getJwksCache](functions/getJwksCache.md)
+- [setJwksCache](functions/setJwksCache.md)
 - [useCodeIdTokenResponseType](functions/useCodeIdTokenResponseType.md)
 - [useJwtResponseMode](functions/useJwtResponseMode.md)
 
@@ -103,9 +105,12 @@ Support from the community to continue maintaining and improving this module is
 - [DiscoveryRequestOptions](interfaces/DiscoveryRequestOptions.md)
 - [DPoPHandle](interfaces/DPoPHandle.md)
 - [DPoPOptions](interfaces/DPoPOptions.md)
+- [ExportedJWKSCache](interfaces/ExportedJWKSCache.md)
 - [GenerateKeyPairOptions](interfaces/GenerateKeyPairOptions.md)
 - [IDToken](interfaces/IDToken.md)
 - [IntrospectionResponse](interfaces/IntrospectionResponse.md)
+- [JWK](interfaces/JWK.md)
+- [JWKS](interfaces/JWKS.md)
 - [ModifyAssertionFunction](interfaces/ModifyAssertionFunction.md)
 - [ModifyAssertionOptions](interfaces/ModifyAssertionOptions.md)
 - [MTLSEndpointAliases](interfaces/MTLSEndpointAliases.md)

docs/functions/getJwksCache.md

@@ -0,0 +1,32 @@
+# Function: getJwksCache()
+
+[💗 Help the project](https://github.com/sponsors/panva)
+
+Support from the community to continue maintaining and improving this module is welcome. If you find the module useful, please consider supporting the project by [becoming a sponsor](https://github.com/sponsors/panva).
+
+***
+
+▸ **getJwksCache**(`config`): [`ExportedJWKSCache`](../interfaces/ExportedJWKSCache.md) \| `undefined`
+
+This function can be used to export the JSON Web Key Set and the timestamp at
+which it was last fetched if the client used the
+[authorization server's JWK Set](../interfaces/ServerMetadata.md#jwks_uri) to validate
+digital signatures.
+
+This function is intended for cloud computing runtimes that cannot keep an in
+memory cache between their code's invocations. Use in runtimes where an in
+memory cache between requests is available is not desirable.
+
+Note: the client only uses the authorization server's JWK Set when
+[enableNonRepudiationChecks](enableNonRepudiationChecks.md), [useJwtResponseMode](useJwtResponseMode.md), or
+[useCodeIdTokenResponseType](useCodeIdTokenResponseType.md) is used.
+
+## Parameters
+
+| Parameter | Type |
+| ------ | ------ |
+| `config` | [`Configuration`](../classes/Configuration.md) |
+
+## Returns
+
+[`ExportedJWKSCache`](../interfaces/ExportedJWKSCache.md) \| `undefined`

docs/functions/setJwksCache.md

@@ -0,0 +1,28 @@
+# Function: setJwksCache()
+
+[💗 Help the project](https://github.com/sponsors/panva)
+
+Support from the community to continue maintaining and improving this module is welcome. If you find the module useful, please consider supporting the project by [becoming a sponsor](https://github.com/sponsors/panva).
+
+***
+
+▸ **setJwksCache**(`config`, `jwksCache`): `void`
+
+DANGER ZONE - Use of this function has security implications that must be
+understood, assessed for applicability, and accepted before use. It is
+critical that the JSON Web Key Set cache only be writable by your own code.
+
+This option is intended for cloud computing runtimes that cannot keep an in
+memory cache between their code's invocations. Use in runtimes where an in
+memory cache between requests is available is not desirable.
+
+## Parameters
+
+| Parameter | Type | Description |
+| ------ | ------ | ------ |
+| `config` | [`Configuration`](../classes/Configuration.md) | - |
+| `jwksCache` | [`ExportedJWKSCache`](../interfaces/ExportedJWKSCache.md) | JWKS Cache previously obtained from [getJwksCache](getJwksCache.md) |
+
+## Returns
+
+`void`

docs/interfaces/ExportedJWKSCache.md

@@ -0,0 +1,19 @@
+# Interface: ExportedJWKSCache
+
+[💗 Help the project](https://github.com/sponsors/panva)
+
+Support from the community to continue maintaining and improving this module is welcome. If you find the module useful, please consider supporting the project by [becoming a sponsor](https://github.com/sponsors/panva).
+
+***
+
+## Properties
+
+### jwks
+
+• **jwks**: [`JWKS`](JWKS.md)
+
+***
+
+### uat
+
+• **uat**: `number`

docs/interfaces/JWK.md

@@ -0,0 +1,71 @@
+# Interface: JWK
+
+[💗 Help the project](https://github.com/sponsors/panva)
+
+Support from the community to continue maintaining and improving this module is welcome. If you find the module useful, please consider supporting the project by [becoming a sponsor](https://github.com/sponsors/panva).
+
+***
+
+## Indexable
+
+ \[`parameter`: `string`\]: [`JsonValue`](../type-aliases/JsonValue.md) \| `undefined`
+
+## Properties
+
+### alg?
+
+• `readonly` `optional` **alg**: `string`
+
+***
+
+### crv?
+
+• `readonly` `optional` **crv**: `string`
+
+***
+
+### e?
+
+• `readonly` `optional` **e**: `string`
+
+***
+
+### key\_ops?
+
+• `readonly` `optional` **key\_ops**: `string`[]
+
+***
+
+### kid?
+
+• `readonly` `optional` **kid**: `string`
+
+***
+
+### kty?
+
+• `readonly` `optional` **kty**: `string`
+
+***
+
+### n?
+
+• `readonly` `optional` **n**: `string`
+
+***
+
+### use?
+
+• `readonly` `optional` **use**: `string`
+
+***
+
+### x?
+
+• `readonly` `optional` **x**: `string`
+
+***
+
+### y?
+
+• `readonly` `optional` **y**: `string`

docs/interfaces/JWKS.md

@@ -0,0 +1,13 @@
+# Interface: JWKS
+
+[💗 Help the project](https://github.com/sponsors/panva)
+
+Support from the community to continue maintaining and improving this module is welcome. If you find the module useful, please consider supporting the project by [becoming a sponsor](https://github.com/sponsors/panva).
+
+***
+
+## Properties
+
+### keys
+
+• `readonly` **keys**: [`JWK`](JWK.md)[]

src/index.ts

@@ -39,6 +39,7 @@ interface Internal {
   hybrid?: HybridImplementation
   nonRepudiation?: NonRepudiationImplementation
   decrypt?: oauth.JweDecryptFunction
+  jwksCache: oauth.JWKSCacheInput
 }
 
 const int = (config: Configuration) => {
@@ -57,13 +58,16 @@ export {
   type AuthorizationDetails,
   type ConfirmationClaims,
   type DeviceAuthorizationResponse,
+  type ExportedJWKSCache,
   type GenerateKeyPairOptions,
   type IDToken,
   type IntrospectionResponse,
   type JsonArray,
   type JsonObject,
   type JsonPrimitive,
   type JsonValue,
+  type JWK,
+  type JWKS,
   type JWSAlgorithm,
   type ModifyAssertionFunction,
   type ModifyAssertionOptions,
@@ -1640,6 +1644,7 @@ export class Configuration
       c,
       auth,
       tlsOnly: true,
+      jwksCache: {},
     })
   }
 
@@ -2060,6 +2065,52 @@ export function allowInsecureRequests(config: Configuration) {
   int(config).tlsOnly = false
 }
 
+/**
+ * DANGER ZONE - Use of this function has security implications that must be
+ * understood, assessed for applicability, and accepted before use. It is
+ * critical that the JSON Web Key Set cache only be writable by your own code.
+ *
+ * This option is intended for cloud computing runtimes that cannot keep an in
+ * memory cache between their code's invocations. Use in runtimes where an in
+ * memory cache between requests is available is not desirable.
+ *
+ * @param jwksCache JWKS Cache previously obtained from {@link getJwksCache}
+ *
+ * @group Advanced Configuration
+ */
+export function setJwksCache(
+  config: Configuration,
+  jwksCache: oauth.ExportedJWKSCache,
+) {
+  int(config).jwksCache = structuredClone(jwksCache)
+}
+
+/**
+ * This function can be used to export the JSON Web Key Set and the timestamp at
+ * which it was last fetched if the client used the
+ * {@link ServerMetadata.jwks_uri authorization server's JWK Set} to validate
+ * digital signatures.
+ *
+ * This function is intended for cloud computing runtimes that cannot keep an in
+ * memory cache between their code's invocations. Use in runtimes where an in
+ * memory cache between requests is available is not desirable.
+ *
+ * Note: the client only uses the authorization server's JWK Set when
+ * {@link enableNonRepudiationChecks}, {@link useJwtResponseMode}, or
+ * {@link useCodeIdTokenResponseType} is used.
+ *
+ * @group Advanced Configuration
+ */
+export function getJwksCache(
+  config: Configuration,
+): oauth.ExportedJWKSCache | undefined {
+  const cache = int(config).jwksCache
+  if (cache.uat) {
+    return cache as oauth.ExportedJWKSCache
+  }
+  return undefined
+}
+
 /**
  * Enables validating the JWS Signature of either a JWT {@link !Response.body} or
  * {@link TokenEndpointResponse.id_token} of a processed {@link !Response} such as
@@ -2116,13 +2167,14 @@ export function enableNonRepudiationChecks(config: Configuration) {
   checkConfig(config)
 
   int(config).nonRepudiation = (response) => {
-    const { as, fetch, tlsOnly, timeout } = int(config)
+    const { as, fetch, tlsOnly, timeout, jwksCache } = int(config)
     return oauth
       .validateApplicationLevelSignature(as, response, {
         [oauth.customFetch]: fetch,
         [oauth.allowInsecureRequests]: !tlsOnly,
         headers: new Headers(headers),
         signal: signal(timeout),
+        [oauth.jwksCache]: jwksCache,
       })
       .catch(errorHandler)
   }
@@ -2565,14 +2617,15 @@ async function validateJARMResponse(
   authorizationResponse: URL,
   expectedState: string | typeof skipStateCheck | undefined,
 ): Promise<URLSearchParams> {
-  const { as, c, fetch, tlsOnly, timeout, decrypt } = int(config)
+  const { as, c, fetch, tlsOnly, timeout, decrypt, jwksCache } = int(config)
   return oauth
     .validateJwtAuthResponse(as, c, authorizationResponse, expectedState, {
       [oauth.customFetch]: fetch,
       [oauth.allowInsecureRequests]: !tlsOnly,
       headers: new Headers(headers),
       signal: signal(timeout),
       [oauth.jweDecrypt]: decrypt,
+      [oauth.jwksCache]: jwksCache,
     })
     .catch(errorHandler)
 }
@@ -2599,7 +2652,7 @@ async function validateCodeIdTokenResponse(
     )
   }
 
-  const { as, c, fetch, tlsOnly, timeout, decrypt } = int(config)
+  const { as, c, fetch, tlsOnly, timeout, decrypt, jwksCache } = int(config)
 
   return (
     fapi
@@ -2611,6 +2664,7 @@ async function validateCodeIdTokenResponse(
     headers: new Headers(headers),
     signal: signal(timeout),
     [oauth.jweDecrypt]: decrypt,
+    [oauth.jwksCache]: jwksCache,
   }).catch(errorHandler)
 }
 

tap/end2end.ts

@@ -18,6 +18,7 @@ export default (QUnit: QUnit) => {
       | 'dpop'
       | 'jwtUserinfo'
       | 'hybrid'
+      | 'nonrepudiation'
       | 'encryption'
       | 'login'
     >
@@ -31,6 +32,7 @@ export default (QUnit: QUnit) => {
       hybrid: false,
       login: false,
       encryption: false,
+      nonrepudiation: false,
     }
     for (const flag of flags) {
       conf[flag] = true
@@ -40,6 +42,8 @@ export default (QUnit: QUnit) => {
 
   const testCases = [
     options(),
+    options('nonrepudiation'),
+    options('nonrepudiation', 'encryption'),
     options('par'),
     options('jar'),
     options('dpop'),
@@ -55,7 +59,16 @@ export default (QUnit: QUnit) => {
   ]
 
   for (const config of testCases) {
-    const { jarm, par, jar, dpop, jwtUserinfo, hybrid, encryption } = config
+    const {
+      jarm,
+      par,
+      jar,
+      dpop,
+      jwtUserinfo,
+      hybrid,
+      encryption,
+      nonrepudiation,
+    } = config
 
     function label(config: Record<string, boolean>) {
       const keys = Object.keys(
@@ -89,10 +102,12 @@ export default (QUnit: QUnit) => {
       )
 
       const execute: Array<(config: lib.Configuration) => void> = [
-        lib.enableNonRepudiationChecks,
         lib.allowInsecureRequests,
       ]
 
+      if (nonrepudiation) {
+        execute.push(lib.enableNonRepudiationChecks)
+      }
       if (jarm) {
         execute.push(lib.useJwtResponseMode)
       }
@@ -222,6 +237,14 @@ export default (QUnit: QUnit) => {
         DPoP,
       })
 
+      if (jarm || hybrid || nonrepudiation) {
+        const cache = lib.getJwksCache(client)
+        t.ok(cache?.uat)
+        t.ok(cache?.jwks)
+      } else {
+        t.notOk(lib.getJwksCache(client))
+      }
+
       t.ok(1)
     })
   }