Godeps: update go-oidc for updates to client and provider metadata

Godeps/Godeps.json

@@ -16,23 +16,23 @@
 		},
 		{
 			"ImportPath": "github.com/coreos/go-oidc/http",
-			"Rev": "145916abb78708694762ff359ab1e34c47c7947f"
+			"Rev": "6039032c0b15517897116d333ead8edf38792437"
 		},
 		{
 			"ImportPath": "github.com/coreos/go-oidc/jose",
-			"Rev": "145916abb78708694762ff359ab1e34c47c7947f"
+			"Rev": "6039032c0b15517897116d333ead8edf38792437"
 		},
 		{
 			"ImportPath": "github.com/coreos/go-oidc/key",
-			"Rev": "145916abb78708694762ff359ab1e34c47c7947f"
+			"Rev": "6039032c0b15517897116d333ead8edf38792437"
 		},
 		{
 			"ImportPath": "github.com/coreos/go-oidc/oauth2",
-			"Rev": "145916abb78708694762ff359ab1e34c47c7947f"
+			"Rev": "6039032c0b15517897116d333ead8edf38792437"
 		},
 		{
 			"ImportPath": "github.com/coreos/go-oidc/oidc",
-			"Rev": "145916abb78708694762ff359ab1e34c47c7947f"
+			"Rev": "6039032c0b15517897116d333ead8edf38792437"
 		},
 		{
 			"ImportPath": "github.com/coreos/pkg/capnslog",

Godeps/_workspace/src/github.com/coreos/go-oidc/jose/jose.go

@@ -13,6 +13,57 @@ const (
 	HeaderKeyID        = "kid"
 )
 
+const (
+	// Encryption Algorithm Header Parameter Values for JWS
+	// See: https://tools.ietf.org/html/draft-ietf-jose-json-web-algorithms-40#page-6
+	AlgHS256 = "HS256"
+	AlgHS384 = "HS384"
+	AlgHS512 = "HS512"
+	AlgRS256 = "RS256"
+	AlgRS384 = "RS384"
+	AlgRS512 = "RS512"
+	AlgES256 = "ES256"
+	AlgES384 = "ES384"
+	AlgES512 = "ES512"
+	AlgPS256 = "PS256"
+	AlgPS384 = "PS384"
+	AlgPS512 = "PS512"
+	AlgNone  = "none"
+)
+
+const (
+	// Algorithm Header Parameter Values for JWE
+	// See: https://tools.ietf.org/html/draft-ietf-jose-json-web-algorithms-40#section-4.1
+	AlgRSA15            = "RSA1_5"
+	AlgRSAOAEP          = "RSA-OAEP"
+	AlgRSAOAEP256       = "RSA-OAEP-256"
+	AlgA128KW           = "A128KW"
+	AlgA192KW           = "A192KW"
+	AlgA256KW           = "A256KW"
+	AlgDir              = "dir"
+	AlgECDHES           = "ECDH-ES"
+	AlgECDHESA128KW     = "ECDH-ES+A128KW"
+	AlgECDHESA192KW     = "ECDH-ES+A192KW"
+	AlgECDHESA256KW     = "ECDH-ES+A256KW"
+	AlgA128GCMKW        = "A128GCMKW"
+	AlgA192GCMKW        = "A192GCMKW"
+	AlgA256GCMKW        = "A256GCMKW"
+	AlgPBES2HS256A128KW = "PBES2-HS256+A128KW"
+	AlgPBES2HS384A192KW = "PBES2-HS384+A192KW"
+	AlgPBES2HS512A256KW = "PBES2-HS512+A256KW"
+)
+
+const (
+	// Encryption Algorithm Header Parameter Values for JWE
+	// See: https://tools.ietf.org/html/draft-ietf-jose-json-web-algorithms-40#page-22
+	EncA128CBCHS256 = "A128CBC-HS256"
+	EncA128CBCHS384 = "A128CBC-HS384"
+	EncA256CBCHS512 = "A256CBC-HS512"
+	EncA128GCM      = "A128GCM"
+	EncA192GCM      = "A192GCM"
+	EncA256GCM      = "A256GCM"
+)
+
 type JOSEHeader map[string]string
 
 func (j JOSEHeader) Validate() error {

Godeps/_workspace/src/github.com/coreos/go-oidc/jose/jwk.go

@@ -70,6 +70,10 @@ func (j *JWK) UnmarshalJSON(data []byte) error {
 	return nil
 }
 
+type JWKSet struct {
+	Keys []JWK `json:"keys"`
+}
+
 func decodeExponent(e string) (int, error) {
 	decE, err := decodeBase64URLPaddingOptional(e)
 	if err != nil {

Godeps/_workspace/src/github.com/coreos/go-oidc/oauth2/oauth2.go

@@ -8,14 +8,49 @@ import (
 	"mime"
 	"net/http"
 	"net/url"
+	"sort"
 	"strconv"
 	"strings"
 
 	phttp "github.com/coreos/go-oidc/http"
 )
 
+// ResponseTypesEqual compares two response_type values. If either
+// contains a space, it is treated as an unordered list. For example,
+// comparing "code id_token" and "id_token code" would evaluate to true.
+func ResponseTypesEqual(r1, r2 string) bool {
+	if !strings.Contains(r1, " ") || !strings.Contains(r2, " ") {
+		// fast route, no split needed
+		return r1 == r2
+	}
+
+	// split, sort, and compare
+	r1Fields := strings.Fields(r1)
+	r2Fields := strings.Fields(r2)
+	if len(r1Fields) != len(r2Fields) {
+		return false
+	}
+	sort.Strings(r1Fields)
+	sort.Strings(r2Fields)
+	for i, r1Field := range r1Fields {
+		if r1Field != r2Fields[i] {
+			return false
+		}
+	}
+	return true
+}
+
 const (
+	// OAuth2.0 response types registered by OIDC.
+	//
+	// See: https://openid.net/specs/oauth-v2-multiple-response-types-1_0.html#RegistryContents
 	ResponseTypeCode             = "code"
+	ResponseTypeCodeIDToken      = "code id_token"
+	ResponseTypeCodeIDTokenToken = "code id_token token"
+	ResponseTypeIDToken          = "id_token"
+	ResponseTypeIDTokenToken     = "id_token token"
+	ResponseTypeToken            = "token"
+	ResponseTypeNone             = "none"
 )
 
 const (

Godeps/_workspace/src/github.com/coreos/go-oidc/oidc/client.go

@@ -1,9 +1,11 @@
 package oidc
 
 import (
+	"encoding/json"
 	"errors"
 	"fmt"
 	"net/http"
+	"net/mail"
 	"net/url"
 	"sync"
 	"time"
@@ -36,23 +38,518 @@ type ClientIdentity struct {
 	Metadata    ClientMetadata
 }
 
-type ClientMetadata struct {
-	RedirectURLs []url.URL
+type JWAOptions struct {
+	// SigningAlg specifies an JWA alg for signing JWTs.
+	//
+	// Specifying this field implies different actions depending on the context. It may
+	// require objects be serialized and signed as a JWT instead of plain JSON, or
+	// require an existing JWT object use the specified alg.
+	//
+	// See: http://openid.net/specs/openid-connect-registration-1_0.html#ClientMetadata
+	SigningAlg string
+	// EncryptionAlg, if provided, specifies that the returned or sent object be stored
+	// (or nested) within a JWT object and encrypted with the provided JWA alg.
+	EncryptionAlg string
+	// EncryptionEnc specifies the JWA enc algorithm to use with EncryptionAlg. If
+	// EncryptionAlg is provided and EncryptionEnc is omitted, this field defaults
+	// to A128CBC-HS256.
+	//
+	// If EncryptionEnc is provided EncryptionAlg must also be specified.
+	EncryptionEnc string
 }
 
+func (opt JWAOptions) valid() error {
+	if opt.EncryptionEnc != "" && opt.EncryptionAlg == "" {
+		return errors.New("encryption encoding provided with no encryption algorithm")
+	}
+	return nil
+}
+
+func (opt JWAOptions) defaults() JWAOptions {
+	if opt.EncryptionAlg != "" && opt.EncryptionEnc == "" {
+		opt.EncryptionEnc = jose.EncA128CBCHS256
+	}
+	return opt
+}
+
+var (
+	// Ensure ClientMetadata satisfies these interfaces.
+	_ json.Marshaler   = &ClientMetadata{}
+	_ json.Unmarshaler = &ClientMetadata{}
+)
+
+// ClientMetadata holds metadata that the authorization server associates
+// with a client identifier. The fields range from human-facing display
+// strings such as client name, to items that impact the security of the
+// protocol, such as the list of valid redirect URIs.
+//
+// See http://openid.net/specs/openid-connect-registration-1_0.html#ClientMetadata
+//
+// TODO: support language specific claim representations
+// http://openid.net/specs/openid-connect-registration-1_0.html#LanguagesAndScripts
+type ClientMetadata struct {
+	RedirectURIs []url.URL // Required
+
+	// A list of OAuth 2.0 "response_type" values that the client wishes to restrict
+	// itself to. Either "code", "token", or another registered extension.
+	//
+	// If omitted, only "code" will be used.
+	ResponseTypes []string
+	// A list of OAuth 2.0 grant types the client wishes to restrict itself to.
+	// The grant type values used by OIDC are "authorization_code", "implicit",
+	// and "refresh_token".
+	//
+	// If ommitted, only "authorization_code" will be used.
+	GrantTypes []string
+	// "native" or "web". If omitted, "web".
+	ApplicationType string
+
+	// List of email addresses.
+	Contacts []mail.Address
+	// Name of client to be presented to the end-user.
+	ClientName string
+	// URL that references a logo for the Client application.
+	LogoURI *url.URL
+	// URL of the home page of the Client.
+	ClientURI *url.URL
+	// Profile data policies and terms of use to be provided to the end user.
+	PolicyURI         *url.URL
+	TermsOfServiceURI *url.URL
+
+	// URL to or the value of the client's JSON Web Key Set document.
+	JWKSURI *url.URL
+	JWKS    *jose.JWKSet
+
+	// URL referencing a flie with a single JSON array of redirect URIs.
+	SectorIdentifierURI *url.URL
+
+	SubjectType string
+
+	// Options to restrict the JWS alg and enc values used for server responses and requests.
+	IDTokenResponseOptions  JWAOptions
+	UserInfoResponseOptions JWAOptions
+	RequestObjectOptions    JWAOptions
+
+	// Client requested authorization method and signing options for the token endpoint.
+	//
+	// Defaults to "client_secret_basic"
+	TokenEndpointAuthMethod     string
+	TokenEndpointAuthSigningAlg string
+
+	// DefaultMaxAge specifies the maximum amount of time in seconds before an authorized
+	// user must reauthroize.
+	//
+	// If 0, no limitation is placed on the maximum.
+	DefaultMaxAge int64
+	// RequireAuthTime specifies if the auth_time claim in the ID token is required.
+	RequireAuthTime bool
+
+	// Default Authentication Context Class Reference values for authentication requests.
+	DefaultACRValues []string
+
+	// URI that a third party can use to initiate a login by the relaying party.
+	//
+	// See: http://openid.net/specs/openid-connect-core-1_0.html#ThirdPartyInitiatedLogin
+	InitiateLoginURI *url.URL
+	// Pre-registered request_uri values that may be cached by the server.
+	RequestURIs []url.URL
+}
+
+// Defaults returns a shallow copy of ClientMetadata with default
+// values replacing omitted fields.
+func (m ClientMetadata) Defaults() ClientMetadata {
+	if len(m.ResponseTypes) == 0 {
+		m.ResponseTypes = []string{oauth2.ResponseTypeCode}
+	}
+	if len(m.GrantTypes) == 0 {
+		m.GrantTypes = []string{oauth2.GrantTypeAuthCode}
+	}
+	if m.ApplicationType == "" {
+		m.ApplicationType = "web"
+	}
+	if m.TokenEndpointAuthMethod == "" {
+		m.TokenEndpointAuthMethod = oauth2.AuthMethodClientSecretBasic
+	}
+	m.IDTokenResponseOptions = m.IDTokenResponseOptions.defaults()
+	m.UserInfoResponseOptions = m.UserInfoResponseOptions.defaults()
+	m.RequestObjectOptions = m.RequestObjectOptions.defaults()
+	return m
+}
+
+func (m *ClientMetadata) MarshalJSON() ([]byte, error) {
+	e := m.toEncodableStruct()
+	return json.Marshal(&e)
+}
+
+func (m *ClientMetadata) UnmarshalJSON(data []byte) error {
+	var e encodableClientMetadata
+	if err := json.Unmarshal(data, &e); err != nil {
+		return err
+	}
+	meta, err := e.toStruct()
+	if err != nil {
+		return err
+	}
+	if err := meta.Valid(); err != nil {
+		return err
+	}
+	*m = meta
+	return nil
+}
+
+type encodableClientMetadata struct {
+	RedirectURIs                 []string     `json:"redirect_uris"` // Required
+	ResponseTypes                []string     `json:"response_types,omitempty"`
+	GrantTypes                   []string     `json:"grant_types,omitempty"`
+	ApplicationType              string       `json:"application_type,omitempty"`
+	Contacts                     []string     `json:"contacts,omitempty"`
+	ClientName                   string       `json:"client_name,omitempty"`
+	LogoURI                      string       `json:"logo_uri,omitempty"`
+	ClientURI                    string       `json:"client_uri,omitempty"`
+	PolicyURI                    string       `json:"policy_uri,omitempty"`
+	TermsOfServiceURI            string       `json:"tos_uri,omitempty"`
+	JWKSURI                      string       `json:"jwks_uri,omitempty"`
+	JWKS                         *jose.JWKSet `json:"jwks,omitempty"`
+	SectorIdentifierURI          string       `json:"sector_identifier_uri,omitempty"`
+	SubjectType                  string       `json:"subject_type,omitempty"`
+	IDTokenSignedResponseAlg     string       `json:"id_token_signed_response_alg,omitempty"`
+	IDTokenEncryptedResponseAlg  string       `json:"id_token_encrypted_response_alg,omitempty"`
+	IDTokenEncryptedResponseEnc  string       `json:"id_token_encrypted_response_enc,omitempty"`
+	UserInfoSignedResponseAlg    string       `json:"userinfo_signed_response_alg,omitempty"`
+	UserInfoEncryptedResponseAlg string       `json:"userinfo_encrypted_response_alg,omitempty"`
+	UserInfoEncryptedResponseEnc string       `json:"userinfo_encrypted_response_enc,omitempty"`
+	RequestObjectSigningAlg      string       `json:"request_object_signing_alg,omitempty"`
+	RequestObjectEncryptionAlg   string       `json:"request_object_encryption_alg,omitempty"`
+	RequestObjectEncryptionEnc   string       `json:"request_object_encryption_enc,omitempty"`
+	TokenEndpointAuthMethod      string       `json:"token_endpoint_auth_method,omitempty"`
+	TokenEndpointAuthSigningAlg  string       `json:"token_endpoint_auth_signing_alg,omitempty"`
+	DefaultMaxAge                int64        `json:"default_max_age,omitempty"`
+	RequireAuthTime              bool         `json:"require_auth_time,omitempty"`
+	DefaultACRValues             []string     `json:"default_acr_values,omitempty"`
+	InitiateLoginURI             string       `json:"initiate_login_uri,omitempty"`
+	RequestURIs                  []string     `json:"request_uris,omitempty"`
+}
+
+func (c *encodableClientMetadata) toStruct() (ClientMetadata, error) {
+	p := stickyErrParser{}
+	m := ClientMetadata{
+		RedirectURIs:                p.parseURIs(c.RedirectURIs, "redirect_uris"),
+		ResponseTypes:               c.ResponseTypes,
+		GrantTypes:                  c.GrantTypes,
+		ApplicationType:             c.ApplicationType,
+		Contacts:                    p.parseEmails(c.Contacts, "contacts"),
+		ClientName:                  c.ClientName,
+		LogoURI:                     p.parseURI(c.LogoURI, "logo_uri"),
+		ClientURI:                   p.parseURI(c.ClientURI, "client_uri"),
+		PolicyURI:                   p.parseURI(c.PolicyURI, "policy_uri"),
+		TermsOfServiceURI:           p.parseURI(c.TermsOfServiceURI, "tos_uri"),
+		JWKSURI:                     p.parseURI(c.JWKSURI, "jwks_uri"),
+		JWKS:                        c.JWKS,
+		SectorIdentifierURI:         p.parseURI(c.SectorIdentifierURI, "sector_identifier_uri"),
+		SubjectType:                 c.SubjectType,
+		TokenEndpointAuthMethod:     c.TokenEndpointAuthMethod,
+		TokenEndpointAuthSigningAlg: c.TokenEndpointAuthSigningAlg,
+		DefaultMaxAge:               c.DefaultMaxAge,
+		RequireAuthTime:             c.RequireAuthTime,
+		DefaultACRValues:            c.DefaultACRValues,
+		InitiateLoginURI:            p.parseURI(c.InitiateLoginURI, "initiate_login_uri"),
+		RequestURIs:                 p.parseURIs(c.RequestURIs, "request_uris"),
+		IDTokenResponseOptions: JWAOptions{
+			c.IDTokenSignedResponseAlg,
+			c.IDTokenEncryptedResponseAlg,
+			c.IDTokenEncryptedResponseEnc,
+		},
+		UserInfoResponseOptions: JWAOptions{
+			c.UserInfoSignedResponseAlg,
+			c.UserInfoEncryptedResponseAlg,
+			c.UserInfoEncryptedResponseEnc,
+		},
+		RequestObjectOptions: JWAOptions{
+			c.RequestObjectSigningAlg,
+			c.RequestObjectEncryptionAlg,
+			c.RequestObjectEncryptionEnc,
+		},
+	}
+	if p.firstErr != nil {
+		return ClientMetadata{}, p.firstErr
+	}
+	return m, nil
+}
+
+// stickyErrParser parses URIs and email addresses. Once it encounters
+// a parse error, subsequent calls become no-op.
+type stickyErrParser struct {
+	firstErr error
+}
+
+func (p *stickyErrParser) parseURI(s, field string) *url.URL {
+	if p.firstErr != nil || s == "" {
+		return nil
+	}
+	u, err := url.Parse(s)
+	if err == nil {
+		if u.Host == "" {
+			err = errors.New("no host in URI")
+		} else if u.Scheme != "http" && u.Scheme != "https" {
+			err = errors.New("invalid URI scheme")
+		}
+	}
+	if err != nil {
+		p.firstErr = fmt.Errorf("failed to parse %s: %v", field, err)
+		return nil
+	}
+	return u
+}
+
+func (p *stickyErrParser) parseURIs(s []string, field string) []url.URL {
+	if p.firstErr != nil || len(s) == 0 {
+		return nil
+	}
+	uris := make([]url.URL, len(s))
+	for i, val := range s {
+		if val == "" {
+			p.firstErr = fmt.Errorf("invalid URI in field %s", field)
+			return nil
+		}
+		uris[i] = *(p.parseURI(val, field))
+	}
+	return uris
+}
+
+func (p *stickyErrParser) parseEmails(s []string, field string) []mail.Address {
+	if p.firstErr != nil || len(s) == 0 {
+		return nil
+	}
+	addrs := make([]mail.Address, len(s))
+	for i, addr := range s {
+		if addr == "" {
+			p.firstErr = fmt.Errorf("invalid email in field %s", field)
+			return nil
+		}
+		a, err := mail.ParseAddress(addr)
+		if err != nil {
+			p.firstErr = fmt.Errorf("invalid email in field %s: %v", field, err)
+			return nil
+		}
+		addrs[i] = *a
+	}
+	return addrs
+}
+
+func (m *ClientMetadata) toEncodableStruct() encodableClientMetadata {
+	return encodableClientMetadata{
+		RedirectURIs:                 urisToStrings(m.RedirectURIs),
+		ResponseTypes:                m.ResponseTypes,
+		GrantTypes:                   m.GrantTypes,
+		ApplicationType:              m.ApplicationType,
+		Contacts:                     emailsToStrings(m.Contacts),
+		ClientName:                   m.ClientName,
+		LogoURI:                      uriToString(m.LogoURI),
+		ClientURI:                    uriToString(m.ClientURI),
+		PolicyURI:                    uriToString(m.PolicyURI),
+		TermsOfServiceURI:            uriToString(m.TermsOfServiceURI),
+		JWKSURI:                      uriToString(m.JWKSURI),
+		JWKS:                         m.JWKS,
+		SectorIdentifierURI:          uriToString(m.SectorIdentifierURI),
+		SubjectType:                  m.SubjectType,
+		IDTokenSignedResponseAlg:     m.IDTokenResponseOptions.SigningAlg,
+		IDTokenEncryptedResponseAlg:  m.IDTokenResponseOptions.EncryptionAlg,
+		IDTokenEncryptedResponseEnc:  m.IDTokenResponseOptions.EncryptionEnc,
+		UserInfoSignedResponseAlg:    m.UserInfoResponseOptions.SigningAlg,
+		UserInfoEncryptedResponseAlg: m.UserInfoResponseOptions.EncryptionAlg,
+		UserInfoEncryptedResponseEnc: m.UserInfoResponseOptions.EncryptionEnc,
+		RequestObjectSigningAlg:      m.RequestObjectOptions.SigningAlg,
+		RequestObjectEncryptionAlg:   m.RequestObjectOptions.EncryptionAlg,
+		RequestObjectEncryptionEnc:   m.RequestObjectOptions.EncryptionEnc,
+		TokenEndpointAuthMethod:      m.TokenEndpointAuthMethod,
+		TokenEndpointAuthSigningAlg:  m.TokenEndpointAuthSigningAlg,
+		DefaultMaxAge:                m.DefaultMaxAge,
+		RequireAuthTime:              m.RequireAuthTime,
+		DefaultACRValues:             m.DefaultACRValues,
+		InitiateLoginURI:             uriToString(m.InitiateLoginURI),
+		RequestURIs:                  urisToStrings(m.RequestURIs),
+	}
+}
+
+func uriToString(u *url.URL) string {
+	if u == nil {
+		return ""
+	}
+	return u.String()
+}
+
+func urisToStrings(urls []url.URL) []string {
+	if len(urls) == 0 {
+		return nil
+	}
+	sli := make([]string, len(urls))
+	for i, u := range urls {
+		sli[i] = u.String()
+	}
+	return sli
+}
+
+func emailsToStrings(addrs []mail.Address) []string {
+	if len(addrs) == 0 {
+		return nil
+	}
+	sli := make([]string, len(addrs))
+	for i, addr := range addrs {
+		sli[i] = addr.String()
+	}
+	return sli
+}
+
+// Valid determines if a ClientMetadata conforms with the OIDC specification.
+//
+// Valid is called by UnmarshalJSON.
+//
+// NOTE(ericchiang): For development purposes Valid does not mandate 'https' for
+// URLs fields where the OIDC spec requires it. This may change in future releases
+// of this package. See: https://github.com/coreos/go-oidc/issues/34
 func (m *ClientMetadata) Valid() error {
-	if len(m.RedirectURLs) == 0 {
+	if len(m.RedirectURIs) == 0 {
 		return errors.New("zero redirect URLs")
 	}
 
-	for _, u := range m.RedirectURLs {
+	validURI := func(u *url.URL, fieldName string) error {
+		if u.Host == "" {
+			return fmt.Errorf("no host for uri field %s", fieldName)
+		}
 		if u.Scheme != "http" && u.Scheme != "https" {
-			return errors.New("invalid redirect URL: scheme not http/https")
-		} else if u.Host == "" {
-			return errors.New("invalid redirect URL: host empty")
+			return fmt.Errorf("uri field %s scheme is not http or https", fieldName)
+		}
+		return nil
+	}
+
+	uris := []struct {
+		val  *url.URL
+		name string
+	}{
+		{m.LogoURI, "logo_uri"},
+		{m.ClientURI, "client_uri"},
+		{m.PolicyURI, "policy_uri"},
+		{m.TermsOfServiceURI, "tos_uri"},
+		{m.JWKSURI, "jwks_uri"},
+		{m.SectorIdentifierURI, "sector_identifier_uri"},
+		{m.InitiateLoginURI, "initiate_login_uri"},
+	}
+
+	for _, uri := range uris {
+		if uri.val == nil {
+			continue
+		}
+		if err := validURI(uri.val, uri.name); err != nil {
+			return err
 		}
 	}
 
+	uriLists := []struct {
+		vals []url.URL
+		name string
+	}{
+		{m.RedirectURIs, "redirect_uris"},
+		{m.RequestURIs, "request_uris"},
+	}
+	for _, list := range uriLists {
+		for _, uri := range list.vals {
+			if err := validURI(&uri, list.name); err != nil {
+				return err
+			}
+		}
+	}
+
+	options := []struct {
+		option JWAOptions
+		name   string
+	}{
+		{m.IDTokenResponseOptions, "id_token response"},
+		{m.UserInfoResponseOptions, "userinfo response"},
+		{m.RequestObjectOptions, "request_object"},
+	}
+	for _, option := range options {
+		if err := option.option.valid(); err != nil {
+			return fmt.Errorf("invalid JWA values for %s: %v", option.name, err)
+		}
+	}
+	return nil
+}
+
+type ClientRegistrationResponse struct {
+	ClientID                string // Required
+	ClientSecret            string
+	RegistrationAccessToken string
+	RegistrationClientURI   string
+	// If IsZero is true, unspecified.
+	ClientIDIssuedAt time.Time
+	// Time at which the client_secret will expire.
+	// If IsZero is true, it will not expire.
+	ClientSecretExpiresAt time.Time
+
+	ClientMetadata
+}
+
+type encodableClientRegistrationResponse struct {
+	ClientID                string `json:"client_id"` // Required
+	ClientSecret            string `json:"client_secret,omitempty"`
+	RegistrationAccessToken string `json:"registration_access_token,omitempty"`
+	RegistrationClientURI   string `json:"registration_client_uri,omitempty"`
+	ClientIDIssuedAt        int64  `json:"client_id_issued_at,omitempty"`
+	// Time at which the client_secret will expire, in seconds since the epoch.
+	// If 0 it will not expire.
+	ClientSecretExpiresAt int64 `json:"client_secret_expires_at"` // Required
+
+	encodableClientMetadata
+}
+
+func unixToSec(t time.Time) int64 {
+	if t.IsZero() {
+		return 0
+	}
+	return t.Unix()
+}
+
+func (c *ClientRegistrationResponse) MarshalJSON() ([]byte, error) {
+	e := encodableClientRegistrationResponse{
+		ClientID:                c.ClientID,
+		ClientSecret:            c.ClientSecret,
+		RegistrationAccessToken: c.RegistrationAccessToken,
+		RegistrationClientURI:   c.RegistrationClientURI,
+		ClientIDIssuedAt:        unixToSec(c.ClientIDIssuedAt),
+		ClientSecretExpiresAt:   unixToSec(c.ClientSecretExpiresAt),
+		encodableClientMetadata: c.ClientMetadata.toEncodableStruct(),
+	}
+	return json.Marshal(&e)
+}
+
+func secToUnix(sec int64) time.Time {
+	if sec == 0 {
+		return time.Time{}
+	}
+	return time.Unix(sec, 0)
+}
+
+func (c *ClientRegistrationResponse) UnmarshalJSON(data []byte) error {
+	var e encodableClientRegistrationResponse
+	if err := json.Unmarshal(data, &e); err != nil {
+		return err
+	}
+	if e.ClientID == "" {
+		return errors.New("no client_id in client registration response")
+	}
+	metadata, err := e.encodableClientMetadata.toStruct()
+	if err != nil {
+		return err
+	}
+	*c = ClientRegistrationResponse{
+		ClientID:                e.ClientID,
+		ClientSecret:            e.ClientSecret,
+		RegistrationAccessToken: e.RegistrationAccessToken,
+		RegistrationClientURI:   e.RegistrationClientURI,
+		ClientIDIssuedAt:        secToUnix(e.ClientIDIssuedAt),
+		ClientSecretExpiresAt:   secToUnix(e.ClientSecretExpiresAt),
+		ClientMetadata:          metadata,
+	}
 	return nil
 }
 
@@ -133,8 +630,8 @@ func (c *Client) OAuthClient() (*oauth2.Client, error) {
 	ocfg := oauth2.Config{
 		Credentials: oauth2.ClientCredentials(c.credentials),
 		RedirectURL: c.redirectURL,
-		AuthURL:     cfg.AuthEndpoint,
-		TokenURL:    cfg.TokenEndpoint,
+		AuthURL:     cfg.AuthEndpoint.String(),
+		TokenURL:    cfg.TokenEndpoint.String(),
 		Scope:       c.scope,
 		AuthMethod:  authMethod,
 	}
@@ -186,7 +683,7 @@ func (c *Client) maybeSyncKeys() error {
 	}
 
 	cfg := c.providerConfig.Get()
-	r := NewRemotePublicKeyRepo(c.httpClient, cfg.KeysEndpoint)
+	r := NewRemotePublicKeyRepo(c.httpClient, cfg.KeysEndpoint.String())
 	w := &clientKeyRepo{client: c}
 	_, err := key.Sync(r, w)
 	c.lastKeySetSync = time.Now().UTC()
@@ -281,7 +778,7 @@ func (c *Client) VerifyJWT(jwt jose.JWT) error {
 	}
 
 	v := NewJWTVerifier(
-		c.providerConfig.Get().Issuer,
+		c.providerConfig.Get().Issuer.String(),
 		c.credentials.ID,
 		c.maybeSyncKeys, keysFunc)
 

Godeps/_workspace/src/github.com/coreos/go-oidc/oidc/provider.go

@@ -2,8 +2,10 @@ package oidc
 
 import (
 	"encoding/json"
+	"errors"
 	"fmt"
 	"net/http"
+	"net/url"
 	"sync"
 	"time"
 
@@ -19,6 +21,26 @@ var (
 	log = capnslog.NewPackageLogger("github.com/coreos/go-oidc", "http")
 )
 
+const (
+	// Subject Identifier types defined by the OIDC spec. Specifies if the provider
+	// should provide the same sub claim value to all clients (public) or a unique
+	// value for each client (pairwise).
+	//
+	// See: http://openid.net/specs/openid-connect-core-1_0.html#SubjectIDTypes
+	SubjectTypePublic   = "public"
+	SubjectTypePairwise = "pairwise"
+)
+
+var (
+	// Default values for omitted provider config fields.
+	//
+	// Use ProviderConfig's Defaults method to fill a provider config with these values.
+	DefaultGrantTypesSupported               = []string{oauth2.GrantTypeAuthCode, oauth2.GrantTypeImplicit}
+	DefaultResponseModesSupported            = []string{"query", "fragment"}
+	DefaultTokenEndpointAuthMethodsSupported = []string{oauth2.AuthMethodClientSecretBasic}
+	DefaultClaimTypesSupported               = []string{"normal"}
+)
+
 const (
 	MaximumProviderConfigSyncInterval = 24 * time.Hour
 	MinimumProviderConfigSyncInterval = time.Minute
@@ -29,29 +51,414 @@ const (
 // internally configurable for tests
 var minimumProviderConfigSyncInterval = MinimumProviderConfigSyncInterval
 
+var (
+	// Ensure ProviderConfig satisfies these interfaces.
+	_ json.Marshaler   = &ProviderConfig{}
+	_ json.Unmarshaler = &ProviderConfig{}
+)
+
+// ProviderConfig represents the OpenID Provider Metadata specifying what
+// configurations a provider supports.
+//
+// See: http://openid.net/specs/openid-connect-discovery-1_0.html#ProviderMetadata
 type ProviderConfig struct {
+	Issuer               *url.URL // Required
+	AuthEndpoint         *url.URL // Required
+	TokenEndpoint        *url.URL // Required if grant types other than "implicit" are supported
+	UserInfoEndpoint     *url.URL
+	KeysEndpoint         *url.URL // Required
+	RegistrationEndpoint *url.URL
+
+	// Servers MAY choose not to advertise some supported scope values even when this
+	// parameter is used, although those defined in OpenID Core SHOULD be listed, if supported.
+	ScopesSupported []string
+	// OAuth2.0 response types supported.
+	ResponseTypesSupported []string // Required
+	// OAuth2.0 response modes supported.
+	//
+	// If omitted, defaults to DefaultResponseModesSupported.
+	ResponseModesSupported []string
+	// OAuth2.0 grant types supported.
+	//
+	// If omitted, defaults to DefaultGrantTypesSupported.
+	GrantTypesSupported []string
+	ACRValuesSupported  []string
+	// SubjectTypesSupported specifies strategies for providing values for the sub claim.
+	SubjectTypesSupported []string // Required
+
+	// JWA signing and encryption algorith values supported for ID tokens.
+	IDTokenSigningAlgValues    []string // Required
+	IDTokenEncryptionAlgValues []string
+	IDTokenEncryptionEncValues []string
+
+	// JWA signing and encryption algorith values supported for user info responses.
+	UserInfoSigningAlgValues    []string
+	UserInfoEncryptionAlgValues []string
+	UserInfoEncryptionEncValues []string
+
+	// JWA signing and encryption algorith values supported for request objects.
+	ReqObjSigningAlgValues    []string
+	ReqObjEncryptionAlgValues []string
+	ReqObjEncryptionEncValues []string
+
+	TokenEndpointAuthMethodsSupported          []string
+	TokenEndpointAuthSigningAlgValuesSupported []string
+	DisplayValuesSupported                     []string
+	ClaimTypesSupported                        []string
+	ClaimsSupported                            []string
+	ServiceDocs                                *url.URL
+	ClaimsLocalsSupported                      []string
+	UILocalsSupported                          []string
+	ClaimsParameterSupported                   bool
+	RequestParameterSupported                  bool
+	RequestURIParamaterSupported               bool
+	RequireRequestURIRegistration              bool
+
+	Policy         *url.URL
+	TermsOfService *url.URL
+
+	// Not part of the OpenID Provider Metadata
+	ExpiresAt time.Time
+}
+
+// Defaults returns a shallow copy of ProviderConfig with default
+// values replacing omitted fields.
+//
+//     var cfg oidc.ProviderConfig
+//     // Fill provider config with default values for omitted fields.
+//     cfg = cfg.Defaults()
+//
+func (p ProviderConfig) Defaults() ProviderConfig {
+	setDefault := func(val *[]string, defaultVal []string) {
+		if len(*val) == 0 {
+			*val = defaultVal
+		}
+	}
+	setDefault(&p.GrantTypesSupported, DefaultGrantTypesSupported)
+	setDefault(&p.ResponseModesSupported, DefaultResponseModesSupported)
+	setDefault(&p.TokenEndpointAuthMethodsSupported, DefaultTokenEndpointAuthMethodsSupported)
+	setDefault(&p.ClaimTypesSupported, DefaultClaimTypesSupported)
+	return p
+}
+
+func (p *ProviderConfig) MarshalJSON() ([]byte, error) {
+	e := p.toEncodableStruct()
+	return json.Marshal(&e)
+}
+
+func (p *ProviderConfig) UnmarshalJSON(data []byte) error {
+	var e encodableProviderConfig
+	if err := json.Unmarshal(data, &e); err != nil {
+		return err
+	}
+	conf, err := e.toStruct()
+	if err != nil {
+		return err
+	}
+	if err := conf.Valid(); err != nil {
+		return err
+	}
+	*p = conf
+	return nil
+}
+
+type encodableProviderConfig struct {
 	Issuer               string `json:"issuer"`
 	AuthEndpoint         string `json:"authorization_endpoint"`
 	TokenEndpoint        string `json:"token_endpoint"`
+	UserInfoEndpoint     string `json:"userinfo_endpoint,omitempty"`
 	KeysEndpoint         string `json:"jwks_uri"`
-	ResponseTypesSupported            []string  `json:"response_types_supported"`
-	GrantTypesSupported               []string  `json:"grant_types_supported"`
-	SubjectTypesSupported             []string  `json:"subject_types_supported"`
-	IDTokenAlgValuesSupported         []string  `json:"id_token_signing_alg_values_supported"`
-	TokenEndpointAuthMethodsSupported []string  `json:"token_endpoint_auth_methods_supported"`
-	ExpiresAt                         time.Time `json:"-"`
+	RegistrationEndpoint string `json:"registration_endpoint,omitempty"`
+
+	// Use 'omitempty' for all slices as per OIDC spec:
+	// "Claims that return multiple values are represented as JSON arrays.
+	// Claims with zero elements MUST be omitted from the response."
+	// http://openid.net/specs/openid-connect-discovery-1_0.html#ProviderConfigurationResponse
+
+	ScopesSupported        []string `json:"scopes_supported,omitempty"`
+	ResponseTypesSupported []string `json:"response_types_supported,omitempty"`
+	ResponseModesSupported []string `json:"response_modes_supported,omitempty"`
+	GrantTypesSupported    []string `json:"grant_types_supported,omitempty"`
+	ACRValuesSupported     []string `json:"acr_values_supported,omitempty"`
+	SubjectTypesSupported  []string `json:"subject_types_supported,omitempty"`
+
+	IDTokenSigningAlgValues     []string `json:"id_token_signing_alg_values_supported,omitempty"`
+	IDTokenEncryptionAlgValues  []string `json:"id_token_encryption_alg_values_supported,omitempty"`
+	IDTokenEncryptionEncValues  []string `json:"id_token_encryption_enc_values_supported,omitempty"`
+	UserInfoSigningAlgValues    []string `json:"userinfo_signing_alg_values_supported,omitempty"`
+	UserInfoEncryptionAlgValues []string `json:"userinfo_encryption_alg_values_supported,omitempty"`
+	UserInfoEncryptionEncValues []string `json:"userinfo_encryption_enc_values_supported,omitempty"`
+	ReqObjSigningAlgValues      []string `json:"request_object_signing_alg_values_supported,omitempty"`
+	ReqObjEncryptionAlgValues   []string `json:"request_object_encryption_alg_values_supported,omitempty"`
+	ReqObjEncryptionEncValues   []string `json:"request_object_encryption_enc_values_supported,omitempty"`
+
+	TokenEndpointAuthMethodsSupported          []string `json:"token_endpoint_auth_methods_supported,omitempty"`
+	TokenEndpointAuthSigningAlgValuesSupported []string `json:"token_endpoint_auth_signing_alg_values_supported,omitempty"`
+
+	DisplayValuesSupported        []string `json:"display_values_supported,omitempty"`
+	ClaimTypesSupported           []string `json:"claim_types_supported,omitempty"`
+	ClaimsSupported               []string `json:"claims_supported,omitempty"`
+	ServiceDocs                   string   `json:"service_documentation,omitempty"`
+	ClaimsLocalsSupported         []string `json:"claims_locales_supported,omitempty"`
+	UILocalsSupported             []string `json:"ui_locales_supported,omitempty"`
+	ClaimsParameterSupported      bool     `json:"claims_parameter_supported,omitempty"`
+	RequestParameterSupported     bool     `json:"request_parameter_supported,omitempty"`
+	RequestURIParamaterSupported  bool     `json:"request_uri_parameter_supported,omitempty"`
+	RequireRequestURIRegistration bool     `json:"require_request_uri_registration,omitempty"`
+
+	Policy         string `json:"op_policy_uri,omitempty"`
+	TermsOfService string `json:"op_tos_uri,omitempty"`
 }
 
+func (cfg ProviderConfig) toEncodableStruct() encodableProviderConfig {
+	return encodableProviderConfig{
+		Issuer:                                     uriToString(cfg.Issuer),
+		AuthEndpoint:                               uriToString(cfg.AuthEndpoint),
+		TokenEndpoint:                              uriToString(cfg.TokenEndpoint),
+		UserInfoEndpoint:                           uriToString(cfg.UserInfoEndpoint),
+		KeysEndpoint:                               uriToString(cfg.KeysEndpoint),
+		RegistrationEndpoint:                       uriToString(cfg.RegistrationEndpoint),
+		ScopesSupported:                            cfg.ScopesSupported,
+		ResponseTypesSupported:                     cfg.ResponseTypesSupported,
+		ResponseModesSupported:                     cfg.ResponseModesSupported,
+		GrantTypesSupported:                        cfg.GrantTypesSupported,
+		ACRValuesSupported:                         cfg.ACRValuesSupported,
+		SubjectTypesSupported:                      cfg.SubjectTypesSupported,
+		IDTokenSigningAlgValues:                    cfg.IDTokenSigningAlgValues,
+		IDTokenEncryptionAlgValues:                 cfg.IDTokenEncryptionAlgValues,
+		IDTokenEncryptionEncValues:                 cfg.IDTokenEncryptionEncValues,
+		UserInfoSigningAlgValues:                   cfg.UserInfoSigningAlgValues,
+		UserInfoEncryptionAlgValues:                cfg.UserInfoEncryptionAlgValues,
+		UserInfoEncryptionEncValues:                cfg.UserInfoEncryptionEncValues,
+		ReqObjSigningAlgValues:                     cfg.ReqObjSigningAlgValues,
+		ReqObjEncryptionAlgValues:                  cfg.ReqObjEncryptionAlgValues,
+		ReqObjEncryptionEncValues:                  cfg.ReqObjEncryptionEncValues,
+		TokenEndpointAuthMethodsSupported:          cfg.TokenEndpointAuthMethodsSupported,
+		TokenEndpointAuthSigningAlgValuesSupported: cfg.TokenEndpointAuthSigningAlgValuesSupported,
+		DisplayValuesSupported:                     cfg.DisplayValuesSupported,
+		ClaimTypesSupported:                        cfg.ClaimTypesSupported,
+		ClaimsSupported:                            cfg.ClaimsSupported,
+		ServiceDocs:                                uriToString(cfg.ServiceDocs),
+		ClaimsLocalsSupported:                      cfg.ClaimsLocalsSupported,
+		UILocalsSupported:                          cfg.UILocalsSupported,
+		ClaimsParameterSupported:                   cfg.ClaimsParameterSupported,
+		RequestParameterSupported:                  cfg.RequestParameterSupported,
+		RequestURIParamaterSupported:               cfg.RequestURIParamaterSupported,
+		RequireRequestURIRegistration:              cfg.RequireRequestURIRegistration,
+		Policy:         uriToString(cfg.Policy),
+		TermsOfService: uriToString(cfg.TermsOfService),
+	}
+}
+
+func (e encodableProviderConfig) toStruct() (ProviderConfig, error) {
+	p := stickyErrParser{}
+	conf := ProviderConfig{
+		Issuer:                                     p.parseURI(e.Issuer, "issuer"),
+		AuthEndpoint:                               p.parseURI(e.AuthEndpoint, "authorization_endpoint"),
+		TokenEndpoint:                              p.parseURI(e.TokenEndpoint, "token_endpoint"),
+		UserInfoEndpoint:                           p.parseURI(e.UserInfoEndpoint, "userinfo_endpoint"),
+		KeysEndpoint:                               p.parseURI(e.KeysEndpoint, "jwks_uri"),
+		RegistrationEndpoint:                       p.parseURI(e.RegistrationEndpoint, "registration_endpoint"),
+		ScopesSupported:                            e.ScopesSupported,
+		ResponseTypesSupported:                     e.ResponseTypesSupported,
+		ResponseModesSupported:                     e.ResponseModesSupported,
+		GrantTypesSupported:                        e.GrantTypesSupported,
+		ACRValuesSupported:                         e.ACRValuesSupported,
+		SubjectTypesSupported:                      e.SubjectTypesSupported,
+		IDTokenSigningAlgValues:                    e.IDTokenSigningAlgValues,
+		IDTokenEncryptionAlgValues:                 e.IDTokenEncryptionAlgValues,
+		IDTokenEncryptionEncValues:                 e.IDTokenEncryptionEncValues,
+		UserInfoSigningAlgValues:                   e.UserInfoSigningAlgValues,
+		UserInfoEncryptionAlgValues:                e.UserInfoEncryptionAlgValues,
+		UserInfoEncryptionEncValues:                e.UserInfoEncryptionEncValues,
+		ReqObjSigningAlgValues:                     e.ReqObjSigningAlgValues,
+		ReqObjEncryptionAlgValues:                  e.ReqObjEncryptionAlgValues,
+		ReqObjEncryptionEncValues:                  e.ReqObjEncryptionEncValues,
+		TokenEndpointAuthMethodsSupported:          e.TokenEndpointAuthMethodsSupported,
+		TokenEndpointAuthSigningAlgValuesSupported: e.TokenEndpointAuthSigningAlgValuesSupported,
+		DisplayValuesSupported:                     e.DisplayValuesSupported,
+		ClaimTypesSupported:                        e.ClaimTypesSupported,
+		ClaimsSupported:                            e.ClaimsSupported,
+		ServiceDocs:                                p.parseURI(e.ServiceDocs, "service_documentation"),
+		ClaimsLocalsSupported:                      e.ClaimsLocalsSupported,
+		UILocalsSupported:                          e.UILocalsSupported,
+		ClaimsParameterSupported:                   e.ClaimsParameterSupported,
+		RequestParameterSupported:                  e.RequestParameterSupported,
+		RequestURIParamaterSupported:               e.RequestURIParamaterSupported,
+		RequireRequestURIRegistration:              e.RequireRequestURIRegistration,
+		Policy:         p.parseURI(e.Policy, "op_policy-uri"),
+		TermsOfService: p.parseURI(e.TermsOfService, "op_tos_uri"),
+	}
+	if p.firstErr != nil {
+		return ProviderConfig{}, p.firstErr
+	}
+	return conf, nil
+}
+
+// Empty returns if a ProviderConfig holds no information.
+//
+// This case generally indicates a ProviderConfigGetter has experienced an error
+// and has nothing to report.
 func (p ProviderConfig) Empty() bool {
-	return p.Issuer == ""
+	return p.Issuer == nil
+}
+
+func contains(sli []string, ele string) bool {
+	for _, s := range sli {
+		if s == ele {
+			return true
+		}
+	}
+	return false
+}
+
+// Valid determines if a ProviderConfig conforms with the OIDC specification.
+// If Valid returns successfully it guarantees required field are non-nil and
+// URLs are well formed.
+//
+// Valid is called by UnmarshalJSON.
+//
+// NOTE(ericchiang): For development purposes Valid does not mandate 'https' for
+// URLs fields where the OIDC spec requires it. This may change in future releases
+// of this package. See: https://github.com/coreos/go-oidc/issues/34
+func (p ProviderConfig) Valid() error {
+	grantTypes := p.GrantTypesSupported
+	if len(grantTypes) == 0 {
+		grantTypes = DefaultGrantTypesSupported
+	}
+	implicitOnly := true
+	for _, grantType := range grantTypes {
+		if grantType != oauth2.GrantTypeImplicit {
+			implicitOnly = false
+			break
+		}
+	}
+
+	if len(p.SubjectTypesSupported) == 0 {
+		return errors.New("missing required field subject_types_supported")
+	}
+	if len(p.IDTokenSigningAlgValues) == 0 {
+		return errors.New("missing required field id_token_signing_alg_values_supported")
+	}
+
+	if len(p.ScopesSupported) != 0 && !contains(p.ScopesSupported, "openid") {
+		return errors.New("scoped_supported must be unspecified or include 'openid'")
+	}
+
+	if !contains(p.IDTokenSigningAlgValues, "RS256") {
+		return errors.New("id_token_signing_alg_values_supported must include 'RS256'")
+	}
+	if contains(p.TokenEndpointAuthMethodsSupported, "none") {
+		return errors.New("token_endpoint_auth_signing_alg_values_supported cannot include 'none'")
+	}
+
+	uris := []struct {
+		val      *url.URL
+		name     string
+		required bool
+	}{
+		{p.Issuer, "issuer", true},
+		{p.AuthEndpoint, "authorization_endpoint", true},
+		{p.TokenEndpoint, "token_endpoint", !implicitOnly},
+		{p.UserInfoEndpoint, "userinfo_endpoint", false},
+		{p.KeysEndpoint, "jwks_uri", true},
+		{p.RegistrationEndpoint, "registration_endpoint", false},
+		{p.ServiceDocs, "service_documentation", false},
+		{p.Policy, "op_policy_uri", false},
+		{p.TermsOfService, "op_tos_uri", false},
+	}
+
+	for _, uri := range uris {
+		if uri.val == nil {
+			if !uri.required {
+				continue
+			}
+			return fmt.Errorf("empty value for required uri field %s", uri.name)
+		}
+		if uri.val.Host == "" {
+			return fmt.Errorf("no host for uri field %s", uri.name)
+		}
+		if uri.val.Scheme != "http" && uri.val.Scheme != "https" {
+			return fmt.Errorf("uri field %s schemeis not http or https", uri.name)
+		}
+	}
+	return nil
+}
+
+// Supports determines if provider supports a client given their respective metadata.
+func (p ProviderConfig) Supports(c ClientMetadata) error {
+	if err := p.Valid(); err != nil {
+		return fmt.Errorf("invalid provider config: %v", err)
+	}
+	if err := c.Valid(); err != nil {
+		return fmt.Errorf("invalid client config: %v", err)
+	}
+
+	// Fill default values for omitted fields
+	c = c.Defaults()
+	p = p.Defaults()
+
+	// Do the supported values list the requested one?
+	supports := []struct {
+		supported []string
+		requested string
+		name      string
+	}{
+		{p.IDTokenSigningAlgValues, c.IDTokenResponseOptions.SigningAlg, "id_token_signed_response_alg"},
+		{p.IDTokenEncryptionAlgValues, c.IDTokenResponseOptions.EncryptionAlg, "id_token_encryption_response_alg"},
+		{p.IDTokenEncryptionEncValues, c.IDTokenResponseOptions.EncryptionEnc, "id_token_encryption_response_enc"},
+		{p.UserInfoSigningAlgValues, c.UserInfoResponseOptions.SigningAlg, "userinfo_signed_response_alg"},
+		{p.UserInfoEncryptionAlgValues, c.UserInfoResponseOptions.EncryptionAlg, "userinfo_encryption_response_alg"},
+		{p.UserInfoEncryptionEncValues, c.UserInfoResponseOptions.EncryptionEnc, "userinfo_encryption_response_enc"},
+		{p.ReqObjSigningAlgValues, c.RequestObjectOptions.SigningAlg, "request_object_signing_alg"},
+		{p.ReqObjEncryptionAlgValues, c.RequestObjectOptions.EncryptionAlg, "request_object_encryption_alg"},
+		{p.ReqObjEncryptionEncValues, c.RequestObjectOptions.EncryptionEnc, "request_object_encryption_enc"},
+	}
+	for _, field := range supports {
+		if field.requested == "" {
+			continue
+		}
+		if !contains(field.supported, field.requested) {
+			return fmt.Errorf("provider does not support requested value for field %s", field.name)
+		}
+	}
+
+	stringsEqual := func(s1, s2 string) bool { return s1 == s2 }
+
+	// For lists, are the list of requested values a subset of the supported ones?
+	supportsAll := []struct {
+		supported []string
+		requested []string
+		name      string
+		// OAuth2.0 response_type can be space separated lists where order doesn't matter.
+		// For example "id_token token" is the same as "token id_token"
+		// Support a custom compare method.
+		comp func(s1, s2 string) bool
+	}{
+		{p.GrantTypesSupported, c.GrantTypes, "grant_types", stringsEqual},
+		{p.ResponseTypesSupported, c.ResponseTypes, "response_type", oauth2.ResponseTypesEqual},
+	}
+	for _, field := range supportsAll {
+	requestLoop:
+		for _, req := range field.requested {
+			for _, sup := range field.supported {
+				if field.comp(req, sup) {
+					continue requestLoop
+				}
+			}
+			return fmt.Errorf("provider does not support requested value for field %s", field.name)
+		}
+	}
+
+	// TODO(ericchiang): Are there more checks we feel comfortable with begin strict about?
+
+	return nil
 }
 
 func (p ProviderConfig) SupportsGrantType(grantType string) bool {
 	var supported []string
 	if len(p.GrantTypesSupported) == 0 {
-		// If omitted, the default value is ["authorization_code", "implicit"].
-		// http://openid.net/specs/openid-connect-discovery-1_0.html#ProviderMetadata
-		supported = []string{oauth2.GrantTypeAuthCode, oauth2.GrantTypeImplicit}
+		supported = DefaultGrantTypesSupported
 	} else {
 		supported = p.GrantTypesSupported
 	}
@@ -237,7 +644,7 @@ func (r *httpProviderConfigGetter) Get() (cfg ProviderConfig, err error) {
 
 	// The issuer value returned MUST be identical to the Issuer URL that was directly used to retrieve the configuration information.
 	// http://openid.net/specs/openid-connect-discovery-1_0.html#ProviderConfigurationValidation
-	if !urlEqual(cfg.Issuer, r.issuerURL) {
+	if !urlEqual(cfg.Issuer.String(), r.issuerURL) {
 		err = fmt.Errorf(`"issuer" in config (%v) does not match provided issuer URL (%v)`, cfg.Issuer, r.issuerURL)
 		return
 	}