minio/cmd/config/identity/openid/jwt.go
2020-06-22 12:08:50 -07:00

383 lines
10 KiB
Go

/*
* MinIO Cloud Storage, (C) 2018-2019 MinIO, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package openid
import (
"crypto"
"encoding/json"
"errors"
"fmt"
"io"
"net/http"
"strconv"
"strings"
"time"
jwtgo "github.com/dgrijalva/jwt-go"
"github.com/minio/minio/cmd/config"
"github.com/minio/minio/pkg/auth"
"github.com/minio/minio/pkg/env"
iampolicy "github.com/minio/minio/pkg/iam/policy"
xnet "github.com/minio/minio/pkg/net"
)
// Config - OpenID Config
// RSA authentication target arguments
type Config struct {
JWKS struct {
URL *xnet.URL `json:"url"`
} `json:"jwks"`
URL *xnet.URL `json:"url,omitempty"`
ClaimPrefix string `json:"claimPrefix,omitempty"`
ClaimName string `json:"claimName,omitempty"`
DiscoveryDoc DiscoveryDoc
ClientID string
publicKeys map[string]crypto.PublicKey
transport *http.Transport
closeRespFn func(io.ReadCloser)
}
// PopulatePublicKey - populates a new publickey from the JWKS URL.
func (r *Config) PopulatePublicKey() error {
if r.JWKS.URL == nil || r.JWKS.URL.String() == "" {
return nil
}
transport := http.DefaultTransport
if r.transport != nil {
transport = r.transport
}
client := &http.Client{
Transport: transport,
}
resp, err := client.Get(r.JWKS.URL.String())
if err != nil {
return err
}
defer r.closeRespFn(resp.Body)
if resp.StatusCode != http.StatusOK {
return errors.New(resp.Status)
}
var jwk JWKS
if err = json.NewDecoder(resp.Body).Decode(&jwk); err != nil {
return err
}
for _, key := range jwk.Keys {
r.publicKeys[key.Kid], err = key.DecodePublicKey()
if err != nil {
return err
}
}
return nil
}
// UnmarshalJSON - decodes JSON data.
func (r *Config) UnmarshalJSON(data []byte) error {
// subtype to avoid recursive call to UnmarshalJSON()
type subConfig Config
var sr subConfig
if err := json.Unmarshal(data, &sr); err != nil {
return err
}
ar := Config(sr)
if ar.JWKS.URL == nil || ar.JWKS.URL.String() == "" {
*r = ar
return nil
}
*r = ar
return nil
}
// JWT - rs client grants provider details.
type JWT struct {
Config
}
// GetDefaultExpiration - returns the expiration seconds expected.
func GetDefaultExpiration(dsecs string) (time.Duration, error) {
defaultExpiryDuration := time.Duration(60) * time.Minute // Defaults to 1hr.
if dsecs != "" {
expirySecs, err := strconv.ParseInt(dsecs, 10, 64)
if err != nil {
return 0, auth.ErrInvalidDuration
}
// The duration, in seconds, of the role session.
// The value can range from 900 seconds (15 minutes)
// to 12 hours.
if expirySecs < 900 || expirySecs > 43200 {
return 0, auth.ErrInvalidDuration
}
defaultExpiryDuration = time.Duration(expirySecs) * time.Second
}
return defaultExpiryDuration, nil
}
func updateClaimsExpiry(dsecs string, claims map[string]interface{}) error {
expStr := claims["exp"]
if expStr == "" {
return ErrTokenExpired
}
// No custom duration requested, the claims can be used as is.
if dsecs == "" {
return nil
}
expAt, err := auth.ExpToInt64(expStr)
if err != nil {
return err
}
defaultExpiryDuration, err := GetDefaultExpiration(dsecs)
if err != nil {
return err
}
// Verify if JWT expiry is lesser than default expiry duration,
// if that is the case then set the default expiration to be
// from the JWT expiry claim.
if time.Unix(expAt, 0).UTC().Sub(time.Now().UTC()) < defaultExpiryDuration {
defaultExpiryDuration = time.Unix(expAt, 0).UTC().Sub(time.Now().UTC())
} // else honor the specified expiry duration.
expiry := time.Now().UTC().Add(defaultExpiryDuration).Unix()
claims["exp"] = strconv.FormatInt(expiry, 10) // update with new expiry.
return nil
}
// Validate - validates the access token.
func (p *JWT) Validate(token, dsecs string) (map[string]interface{}, error) {
jp := new(jwtgo.Parser)
jp.ValidMethods = []string{
"RS256", "RS384", "RS512", "ES256", "ES384", "ES512",
"RS3256", "RS3384", "RS3512", "ES3256", "ES3384", "ES3512",
}
keyFuncCallback := func(jwtToken *jwtgo.Token) (interface{}, error) {
kid, ok := jwtToken.Header["kid"].(string)
if !ok {
return nil, fmt.Errorf("Invalid kid value %v", jwtToken.Header["kid"])
}
return p.publicKeys[kid], nil
}
var claims jwtgo.MapClaims
jwtToken, err := jp.ParseWithClaims(token, &claims, keyFuncCallback)
if err != nil {
if err = p.PopulatePublicKey(); err != nil {
return nil, err
}
jwtToken, err = jwtgo.ParseWithClaims(token, &claims, keyFuncCallback)
if err != nil {
return nil, err
}
}
if !jwtToken.Valid {
return nil, ErrTokenExpired
}
if err = updateClaimsExpiry(dsecs, claims); err != nil {
return nil, err
}
return claims, nil
}
// ID returns the provider name and authentication type.
func (p *JWT) ID() ID {
return "jwt"
}
// OpenID keys and envs.
const (
JwksURL = "jwks_url"
ConfigURL = "config_url"
ClaimName = "claim_name"
ClaimPrefix = "claim_prefix"
ClientID = "client_id"
Scopes = "scopes"
EnvIdentityOpenIDClientID = "MINIO_IDENTITY_OPENID_CLIENT_ID"
EnvIdentityOpenIDJWKSURL = "MINIO_IDENTITY_OPENID_JWKS_URL"
EnvIdentityOpenIDURL = "MINIO_IDENTITY_OPENID_CONFIG_URL"
EnvIdentityOpenIDClaimName = "MINIO_IDENTITY_OPENID_CLAIM_NAME"
EnvIdentityOpenIDClaimPrefix = "MINIO_IDENTITY_OPENID_CLAIM_PREFIX"
EnvIdentityOpenIDScopes = "MINIO_IDENTITY_OPENID_SCOPES"
)
// DiscoveryDoc - parses the output from openid-configuration
// for example https://accounts.google.com/.well-known/openid-configuration
type DiscoveryDoc struct {
Issuer string `json:"issuer,omitempty"`
AuthEndpoint string `json:"authorization_endpoint,omitempty"`
TokenEndpoint string `json:"token_endpoint,omitempty"`
UserInfoEndpoint string `json:"userinfo_endpoint,omitempty"`
RevocationEndpoint string `json:"revocation_endpoint,omitempty"`
JwksURI string `json:"jwks_uri,omitempty"`
ResponseTypesSupported []string `json:"response_types_supported,omitempty"`
SubjectTypesSupported []string `json:"subject_types_supported,omitempty"`
IDTokenSigningAlgValuesSupported []string `json:"id_token_signing_alg_values_supported,omitempty"`
ScopesSupported []string `json:"scopes_supported,omitempty"`
TokenEndpointAuthMethods []string `json:"token_endpoint_auth_methods_supported,omitempty"`
ClaimsSupported []string `json:"claims_supported,omitempty"`
CodeChallengeMethodsSupported []string `json:"code_challenge_methods_supported,omitempty"`
}
func parseDiscoveryDoc(u *xnet.URL, transport *http.Transport, closeRespFn func(io.ReadCloser)) (DiscoveryDoc, error) {
d := DiscoveryDoc{}
req, err := http.NewRequest(http.MethodGet, u.String(), nil)
if err != nil {
return d, err
}
clnt := http.Client{
Transport: transport,
}
resp, err := clnt.Do(req)
if err != nil {
clnt.CloseIdleConnections()
return d, err
}
defer closeRespFn(resp.Body)
if resp.StatusCode != http.StatusOK {
return d, err
}
dec := json.NewDecoder(resp.Body)
if err = dec.Decode(&d); err != nil {
return d, err
}
return d, nil
}
// DefaultKVS - default config for OpenID config
var (
DefaultKVS = config.KVS{
config.KV{
Key: ConfigURL,
Value: "",
},
config.KV{
Key: ClientID,
Value: "",
},
config.KV{
Key: ClaimName,
Value: iampolicy.PolicyName,
},
config.KV{
Key: ClaimPrefix,
Value: "",
},
config.KV{
Key: Scopes,
Value: "",
},
config.KV{
Key: JwksURL,
Value: "",
},
}
)
// Enabled returns if jwks is enabled.
func Enabled(kvs config.KVS) bool {
return kvs.Get(JwksURL) != ""
}
// LookupConfig lookup jwks from config, override with any ENVs.
func LookupConfig(kvs config.KVS, transport *http.Transport, closeRespFn func(io.ReadCloser)) (c Config, err error) {
if err = config.CheckValidKeys(config.IdentityOpenIDSubSys, kvs, DefaultKVS); err != nil {
return c, err
}
jwksURL := env.Get(EnvIamJwksURL, "") // Legacy
if jwksURL == "" {
jwksURL = env.Get(EnvIdentityOpenIDJWKSURL, kvs.Get(JwksURL))
}
c = Config{
ClaimName: env.Get(EnvIdentityOpenIDClaimName, kvs.Get(ClaimName)),
ClaimPrefix: env.Get(EnvIdentityOpenIDClaimPrefix, kvs.Get(ClaimPrefix)),
publicKeys: make(map[string]crypto.PublicKey),
ClientID: env.Get(EnvIdentityOpenIDClientID, kvs.Get(ClientID)),
transport: transport,
closeRespFn: closeRespFn,
}
configURL := env.Get(EnvIdentityOpenIDURL, kvs.Get(ConfigURL))
if configURL != "" {
c.URL, err = xnet.ParseHTTPURL(configURL)
if err != nil {
return c, err
}
c.DiscoveryDoc, err = parseDiscoveryDoc(c.URL, transport, closeRespFn)
if err != nil {
return c, err
}
}
if scopeList := env.Get(EnvIdentityOpenIDScopes, kvs.Get(Scopes)); scopeList != "" {
var scopes []string
for _, scope := range strings.Split(scopeList, ",") {
scope = strings.TrimSpace(scope)
if scope == "" {
return c, config.Errorf("empty scope value is not allowed '%s', please refer to our documentation", scopeList)
}
scopes = append(scopes, scope)
}
// Replace the discovery document scopes by client customized scopes.
c.DiscoveryDoc.ScopesSupported = scopes
}
if c.ClaimName == "" {
c.ClaimName = iampolicy.PolicyName
}
if jwksURL == "" {
// Fallback to discovery document jwksURL
jwksURL = c.DiscoveryDoc.JwksURI
}
if jwksURL == "" {
return c, nil
}
c.JWKS.URL, err = xnet.ParseHTTPURL(jwksURL)
if err != nil {
return c, err
}
if err = c.PopulatePublicKey(); err != nil {
return c, err
}
return c, nil
}
// NewJWT - initialize new jwt authenticator.
func NewJWT(c Config) *JWT {
return &JWT{c}
}