ContainerImage.Pinniped/internal/oidc/discovery/discovery_handler.go

98 lines
3.6 KiB
Go

// Copyright 2020-2023 the Pinniped contributors. All Rights Reserved.
// SPDX-License-Identifier: Apache-2.0
// Package discovery provides a handler for the OIDC discovery endpoint.
package discovery
import (
"bytes"
"encoding/json"
"net/http"
"go.pinniped.dev/generated/latest/apis/supervisor/idpdiscovery/v1alpha1"
oidcapi "go.pinniped.dev/generated/latest/apis/supervisor/oidc"
"go.pinniped.dev/internal/oidc"
)
// Metadata holds all fields (that we care about) from the OpenID Provider Metadata section in the
// OpenID Connect Discovery specification:
// https://openid.net/specs/openid-connect-discovery-1_0.html#rfc.section.3.
type Metadata struct {
// vvv Required vvv
Issuer string `json:"issuer"`
AuthorizationEndpoint string `json:"authorization_endpoint"`
TokenEndpoint string `json:"token_endpoint"`
JWKSURI string `json:"jwks_uri"`
ResponseTypesSupported []string `json:"response_types_supported"`
ResponseModesSupported []string `json:"response_modes_supported"`
SubjectTypesSupported []string `json:"subject_types_supported"`
IDTokenSigningAlgValuesSupported []string `json:"id_token_signing_alg_values_supported"`
// ^^^ Required ^^^
// vvv Optional vvv
TokenEndpointAuthMethodsSupported []string `json:"token_endpoint_auth_methods_supported"`
ScopesSupported []string `json:"scopes_supported"`
ClaimsSupported []string `json:"claims_supported"`
// https://datatracker.ietf.org/doc/html/rfc8414#section-2 says, “If omitted, the authorization server does not support PKCE.”
CodeChallengeMethodsSupported []string `json:"code_challenge_methods_supported"`
// ^^^ Optional ^^^
// vvv Custom vvv
v1alpha1.OIDCDiscoveryResponse
// ^^^ Custom ^^^
}
// NewHandler returns an http.Handler that serves an OIDC discovery endpoint.
func NewHandler(issuerURL string) http.Handler {
oidcConfig := Metadata{
Issuer: issuerURL,
AuthorizationEndpoint: issuerURL + oidc.AuthorizationEndpointPath,
TokenEndpoint: issuerURL + oidc.TokenEndpointPath,
JWKSURI: issuerURL + oidc.JWKSEndpointPath,
OIDCDiscoveryResponse: v1alpha1.OIDCDiscoveryResponse{
SupervisorDiscovery: v1alpha1.OIDCDiscoveryResponseIDPEndpoint{
PinnipedIDPsEndpoint: issuerURL + oidc.PinnipedIDPsPathV1Alpha1,
},
},
ResponseTypesSupported: []string{"code"},
ResponseModesSupported: []string{"query", "form_post"},
SubjectTypesSupported: []string{"public"},
IDTokenSigningAlgValuesSupported: []string{"ES256"},
TokenEndpointAuthMethodsSupported: []string{"client_secret_basic"},
CodeChallengeMethodsSupported: []string{"S256"},
ScopesSupported: []string{oidcapi.ScopeOpenID, oidcapi.ScopeOfflineAccess, oidcapi.ScopeRequestAudience, oidcapi.ScopeUsername, oidcapi.ScopeGroups},
ClaimsSupported: []string{oidcapi.IDTokenClaimUsername, oidcapi.IDTokenClaimGroups, oidcapi.IDTokenClaimAdditionalClaims},
}
var b bytes.Buffer
encodeErr := json.NewEncoder(&b).Encode(&oidcConfig)
encodedMetadata := b.Bytes()
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
if r.Method != http.MethodGet {
http.Error(w, `Method not allowed (try GET)`, http.StatusMethodNotAllowed)
return
}
if encodeErr != nil {
http.Error(w, encodeErr.Error(), http.StatusInternalServerError)
return
}
w.Header().Set("Content-Type", "application/json")
if _, err := w.Write(encodedMetadata); err != nil {
http.Error(w, err.Error(), http.StatusInternalServerError)
return
}
})
}