vouch-proxy/pkg/cfg/oauth.go

314 lines
11 KiB
Go

/*
Copyright 2020 The Vouch Proxy Authors.
Use of this source code is governed by The MIT License (MIT) that
can be found in the LICENSE file. Software distributed under The
MIT License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES
OR CONDITIONS OF ANY KIND, either express or implied.
*/
package cfg
import (
"encoding/json"
"errors"
"fmt"
"strings"
"golang.org/x/oauth2"
"golang.org/x/oauth2/github"
"golang.org/x/oauth2/google"
)
var (
// GenOAuth exported OAuth config variable
// TODO: GenOAuth and OAuthClient should be combined
GenOAuth = &oauthConfig{}
// OAuthClient is the configured client which will call the provider
// this actually carries the oauth2 client ala oauthclient.Client(oauth2.NoContext, providerToken)
OAuthClient *oauth2.Config
// OAuthopts authentication options
OAuthopts []oauth2.AuthCodeOption
// Providers static strings to test against
Providers = &OAuthProviders{
Google: "google",
GitHub: "github",
IndieAuth: "indieauth",
ADFS: "adfs",
Azure: "azure",
OIDC: "oidc",
HomeAssistant: "homeassistant",
OpenStax: "openstax",
Nextcloud: "nextcloud",
Alibaba: "alibaba",
}
)
// OAuthProviders holds the stings for
type OAuthProviders struct {
Google string
GitHub string
IndieAuth string
ADFS string
Azure string
OIDC string
HomeAssistant string
OpenStax string
Nextcloud string
Alibaba string
}
// oauth config items endoint for access
// `envconfig` tag is for env var support
// https://github.com/kelseyhightower/envconfig
type oauthConfig struct {
Provider string `mapstructure:"provider"`
ClientID string `mapstructure:"client_id" envconfig:"client_id"`
ClientSecret string `mapstructure:"client_secret" envconfig:"client_secret"`
AuthURL string `mapstructure:"auth_url" envconfig:"auth_url"`
TokenURL string `mapstructure:"token_url" envconfig:"token_url"`
LogoutURL string `mapstructure:"end_session_endpoint" envconfig:"end_session_endpoint"`
RedirectURL string `mapstructure:"callback_url" envconfig:"callback_url"`
RedirectURLs []string `mapstructure:"callback_urls" envconfig:"callback_urls"`
RelyingPartyId string `mapstructure:"relying_party_id" envconfig:"relying_party_id"`
Scopes []string `mapstructure:"scopes"`
// pointer-to-pointer so that the default uninitialized value is nil
Claims **oauthClaimsConfig `mapstructure:"claims"`
UserInfoURL string `mapstructure:"user_info_url" envconfig:"user_info_url"`
UserTeamURL string `mapstructure:"user_team_url" envconfig:"user_team_url"`
UserOrgURL string `mapstructure:"user_org_url" envconfig:"user_org_url"`
PreferredDomain string `mapstructure:"preferredDomain"`
AzureToken string `mapstructure:"azure_token" envconfig:"azure_token"`
CodeChallengeMethod string `mapstructure:"code_challenge_method" envconfig:"code_challenge_method"`
}
type oauthClaimsConfig struct {
UserInfo map[string]*oauthClaimValueConfig `mapstructure:"userinfo" json:"userinfo,omitempty"`
IDToken map[string]*oauthClaimValueConfig `mapstructure:"id_token" json:"id_token,omitempty"`
}
type oauthClaimValueConfig struct {
Essential bool `mapstructure:"essential" json:"essential,omitempty"`
Value interface{} `mapstructure:"value" json:"value,omitempty"`
Values []interface{} `mapstructure:"values" json:"values,omitempty"`
}
func configureOauth() error {
// OAuth defaults and client configuration
if err := UnmarshalKey("oauth", &GenOAuth); err != nil {
return err
}
if GenOAuth.Claims != nil {
claims, err := json.Marshal(GenOAuth.Claims)
if err != nil {
return err
}
log.Infof("setting OAuth param 'claims' to %s", claims)
OAuthopts = append(OAuthopts, oauth2.SetAuthURLParam("claims", string(claims)))
}
return nil
}
func oauthBasicTest() error {
if GenOAuth.Provider != Providers.Google &&
GenOAuth.Provider != Providers.GitHub &&
GenOAuth.Provider != Providers.IndieAuth &&
GenOAuth.Provider != Providers.HomeAssistant &&
GenOAuth.Provider != Providers.ADFS &&
GenOAuth.Provider != Providers.Azure &&
GenOAuth.Provider != Providers.OIDC &&
GenOAuth.Provider != Providers.OpenStax &&
GenOAuth.Provider != Providers.Nextcloud &&
GenOAuth.Provider != Providers.Alibaba {
return errors.New("configuration error: Unknown oauth provider: " + GenOAuth.Provider)
}
// OAuthconfig Checks
switch {
case GenOAuth.ClientID == "":
// everyone has a clientID
return errors.New("configuration error: oauth.client_id not found")
case GenOAuth.Provider != Providers.IndieAuth && GenOAuth.Provider != Providers.HomeAssistant && GenOAuth.Provider != Providers.ADFS && GenOAuth.Provider != Providers.OIDC && GenOAuth.ClientSecret == "":
// everyone except IndieAuth has a clientSecret
// ADFS and OIDC providers also do not require this, but can have it optionally set.
return errors.New("configuration error: oauth.client_secret not found")
case GenOAuth.Provider != Providers.Google && GenOAuth.AuthURL == "":
// everyone except IndieAuth and Google has an authURL
return errors.New("configuration error: oauth.auth_url not found")
case GenOAuth.Provider != Providers.Google && GenOAuth.Provider != Providers.IndieAuth && GenOAuth.Provider != Providers.HomeAssistant && GenOAuth.Provider != Providers.ADFS && GenOAuth.Provider != Providers.Azure && GenOAuth.UserInfoURL == "":
// everyone except IndieAuth, Google and ADFS has an userInfoURL, and Azure does not actively use it
return errors.New("configuration error: oauth.user_info_url not found")
case GenOAuth.CodeChallengeMethod != "" && (GenOAuth.CodeChallengeMethod != "plain" && GenOAuth.CodeChallengeMethod != "S256"):
return errors.New("configuration error: oauth.code_challenge_method must be either 'S256' or 'plain'")
case GenOAuth.Provider == Providers.Azure || GenOAuth.Provider == Providers.ADFS || GenOAuth.Provider == Providers.Nextcloud || GenOAuth.Provider == Providers.OIDC:
checkScopes([]string{"openid", "email", "profile"})
}
if GenOAuth.RedirectURL != "" {
if err := checkCallbackConfig(GenOAuth.RedirectURL); err != nil {
return err
}
}
if len(GenOAuth.RedirectURLs) > 0 {
for _, cb := range GenOAuth.RedirectURLs {
if err := checkCallbackConfig(cb); err != nil {
return err
}
}
}
return nil
}
func checkScopes(scopes []string) {
for _, s := range scopes {
if !arrContains(GenOAuth.Scopes, s) {
log.Warnf("Configuration Warning: for 'oauth.provider: %s', 'oauth.scopes' should usually contain: -%s", GenOAuth.Provider, strings.Join(scopes, " -"))
return
}
}
}
// TODO: all of these methods should become `provider.SetDefaults()` or `provider.SetDefaults(*GenOAuth)`
func setProviderDefaults() {
if GenOAuth.Provider == Providers.Google {
setDefaultsGoogle()
// setDefaultsGoogle also configures the OAuthClient
} else if GenOAuth.Provider == Providers.GitHub {
setDefaultsGitHub()
configureOAuthClient()
} else if GenOAuth.Provider == Providers.ADFS {
setDefaultsADFS()
configureOAuthClient()
} else if GenOAuth.Provider == Providers.Azure {
setDefaultsAzure()
configureOAuthClient()
} else if GenOAuth.Provider == Providers.IndieAuth {
GenOAuth.CodeChallengeMethod = "S256"
configureOAuthClient()
} else {
// OIDC, OpenStax, Nextcloud
configureOAuthClient()
}
}
func setDefaultsGoogle() {
log.Info("configuring Google OAuth")
GenOAuth.UserInfoURL = "https://www.googleapis.com/oauth2/v3/userinfo"
if len(GenOAuth.Scopes) == 0 {
// You have to select a scope from
// https://developers.google.com/identity/protocols/googlescopes#google_sign-in
GenOAuth.Scopes = []string{"email"}
}
OAuthClient = &oauth2.Config{
ClientID: GenOAuth.ClientID,
ClientSecret: GenOAuth.ClientSecret,
Scopes: GenOAuth.Scopes,
Endpoint: google.Endpoint,
RedirectURL: GenOAuth.RedirectURL,
}
if GenOAuth.PreferredDomain != "" {
log.Infof("setting Google OAuth preferred login domain param 'hd' to %s", GenOAuth.PreferredDomain)
OAuthopts = append(OAuthopts, oauth2.SetAuthURLParam("hd", GenOAuth.PreferredDomain))
}
GenOAuth.CodeChallengeMethod = "S256"
}
func setDefaultsADFS() {
log.Info("configuring ADFS OAuth")
if GenOAuth.RelyingPartyId == "" {
GenOAuth.RelyingPartyId = GenOAuth.RedirectURL
}
OAuthopts = append(OAuthopts, oauth2.SetAuthURLParam("resource", GenOAuth.RelyingPartyId))
}
func setDefaultsAzure() {
log.Info("configuring Azure OAuth")
if len(GenOAuth.AzureToken) == 0 {
log.Info("Using Default Azure Token: access_token")
GenOAuth.AzureToken = "access_token"
} else if GenOAuth.AzureToken == "access_token" {
log.Info("Using Azure Token: access_token")
} else if GenOAuth.AzureToken == "id_token" {
log.Info("Using Azure Token: id_token")
} else {
log.Fatal("'oauth.azure_token' must be either 'access_token' or 'id_token'")
}
GenOAuth.CodeChallengeMethod = "S256"
}
func setDefaultsGitHub() {
// log.Info("configuring GitHub OAuth")
if GenOAuth.AuthURL == "" {
GenOAuth.AuthURL = github.Endpoint.AuthURL
}
if GenOAuth.TokenURL == "" {
GenOAuth.TokenURL = github.Endpoint.TokenURL
}
if GenOAuth.UserInfoURL == "" {
GenOAuth.UserInfoURL = "https://api.github.com/user?access_token="
}
if GenOAuth.UserTeamURL == "" {
GenOAuth.UserTeamURL = "https://api.github.com/orgs/:org_id/teams/:team_slug/memberships/:username?access_token="
}
if GenOAuth.UserOrgURL == "" {
GenOAuth.UserOrgURL = "https://api.github.com/orgs/:org_id/members/:username?access_token="
}
if len(GenOAuth.Scopes) == 0 {
// https://github.com/vouch/vouch-proxy/issues/63
// https://developer.github.com/apps/building-oauth-apps/understanding-scopes-for-oauth-apps/
GenOAuth.Scopes = []string{"read:user"}
if len(Cfg.TeamWhiteList) > 0 {
GenOAuth.Scopes = append(GenOAuth.Scopes, "read:org")
}
}
GenOAuth.CodeChallengeMethod = "S256"
}
func configureOAuthClient() {
log.Infof("configuring %s OAuth with Endpoint %s", GenOAuth.Provider, GenOAuth.AuthURL)
OAuthClient = &oauth2.Config{
ClientID: GenOAuth.ClientID,
ClientSecret: GenOAuth.ClientSecret,
Endpoint: oauth2.Endpoint{
AuthURL: GenOAuth.AuthURL,
TokenURL: GenOAuth.TokenURL,
},
RedirectURL: GenOAuth.RedirectURL,
Scopes: GenOAuth.Scopes,
}
}
func checkCallbackConfig(url string) error {
if !strings.Contains(url, "/auth") {
log.Errorf("configuration error: oauth.callback_url (%s) should almost always point at the vouch-proxy '/auth' endpoint", url)
}
found := false
for _, d := range append(Cfg.Domains, Cfg.Cookie.Domain) {
if d != "" && strings.Contains(url, d) {
found = true
break
}
}
if !found {
return fmt.Errorf("configuration error: oauth.callback_url (%s) must be within a configured domains where the cookie will be set: either `vouch.domains` %s or `vouch.cookie.domain` %s", url, Cfg.Domains, Cfg.Cookie.Domain)
}
return nil
}
func arrContains(arr []string, str string) bool {
for _, v := range arr {
if v == str {
return true
}
}
return false
}