fix(idp): provide id_token for tenant id based azure ad (#7188)

* fix(idp): provide id_token for tenant based azure ad

* comments

* remove unintentional changes

internal/api/idp/idp.go

@@ -393,7 +393,7 @@ func (h *Handler) fetchIDPUserFromCode(ctx context.Context, identityProvider idp
 	case *openid.Provider:
 		session = &openid.Session{Provider: provider, Code: code}
 	case *azuread.Provider:
-		session = &azuread.Session{Session: &oauth.Session{Provider: provider.Provider, Code: code}}
+		session = &azuread.Session{Provider: provider, Code: code}
 	case *github.Provider:
 		session = &oauth.Session{Provider: provider.Provider, Code: code}
 	case *gitlab.Provider:

internal/api/ui/login/external_provider_handler.go

@@ -270,7 +270,7 @@ func (l *Login) handleExternalLoginCallback(w http.ResponseWriter, r *http.Reque
 			l.externalAuthFailed(w, r, authReq, nil, nil, err)
 			return
 		}
-		session = &azuread.Session{Session: &oauth.Session{Provider: provider.(*azuread.Provider).Provider, Code: data.Code}}
+		session = &azuread.Session{Provider: provider.(*azuread.Provider), Code: data.Code}
 	case domain.IDPTypeGitHub:
 		provider, err = l.githubProvider(r.Context(), identityProvider)
 		if err != nil {
@@ -1132,7 +1132,7 @@ func tokens(session idp.Session) *oidc.Tokens[*oidc.IDTokenClaims] {
 	case *oauth.Session:
 		return s.Tokens
 	case *azuread.Session:
-		return s.Tokens
+		return s.Tokens()
 	case *apple.Session:
 		return s.Tokens
 	}

internal/command/idp_intent.go

@@ -285,7 +285,7 @@ func tokensForSucceededIDPIntent(session idp.Session, encryptionAlg crypto.Encry
 	case *jwt.Session:
 		tokens = s.Tokens
 	case *azuread.Session:
-		tokens = s.Tokens
+		tokens = s.Tokens()
 	case *apple.Session:
 		tokens = s.Tokens
 	default:

internal/command/idp_intent_test.go

@@ -1166,11 +1166,12 @@ func Test_tokensForSucceededIDPIntent(t *testing.T) {
 			"azure tokens",
 			args{
 				&azuread.Session{
-					Session: &oauth.Session{
+					OAuthSession: &oauth.Session{
 						Tokens: &oidc.Tokens[*oidc.IDTokenClaims]{
 							Token: &oauth2.Token{
 								AccessToken: "accessToken",
 							},
+							IDToken: "idToken",
 						},
 					},
 				},
@@ -1183,7 +1184,7 @@ func Test_tokensForSucceededIDPIntent(t *testing.T) {
 					KeyID:      "id",
 					Crypted:    []byte("accessToken"),
 				},
-				idToken: "",
+				idToken: "idToken",
 				err:     nil,
 			},
 		},

internal/idp/providers/azuread/azuread.go

@@ -13,8 +13,10 @@ import (
 )
 
 const (
+	issuerTemplate   string = "https://login.microsoftonline.com/%s/v2.0"
 	authURLTemplate  string = "https://login.microsoftonline.com/%s/oauth2/v2.0/authorize"
 	tokenURLTemplate string = "https://login.microsoftonline.com/%s/oauth2/v2.0/token"
+	keysURLTemplate  string = "https://login.microsoftonline.com/%s/discovery/v2.0/keys"
 	userURL          string = "https://graph.microsoft.com/v1.0/me"
 	userinfoEndpoint string = "https://graph.microsoft.com/oidc/userinfo"
 
@@ -50,6 +52,16 @@ type Provider struct {
 	options       []oauth.ProviderOpts
 }
 
+// issuer returns the OIDC issuer based on the [TenantType]
+func (p *Provider) issuer() string {
+	return fmt.Sprintf(issuerTemplate, p.tenant)
+}
+
+// keysEndpoint returns the OIDC jwks_url based on the [TenantType]
+func (p *Provider) keysEndpoint() string {
+	return fmt.Sprintf(keysURLTemplate, p.tenant)
+}
+
 type ProviderOptions func(*Provider)
 
 // WithTenant allows to set a [TenantType] (can also be a Tenant ID)

internal/idp/providers/azuread/session.go

@@ -1,17 +1,28 @@
 package azuread
 
 import (
+	"context"
 	"net/http"
 
+	"github.com/zitadel/oidc/v3/pkg/client/rp"
 	httphelper "github.com/zitadel/oidc/v3/pkg/http"
 	"github.com/zitadel/oidc/v3/pkg/oidc"
 
+	"github.com/zitadel/zitadel/internal/idp"
 	"github.com/zitadel/zitadel/internal/idp/providers/oauth"
 )
 
-// Session extends the [oauth.Session] to extend it with the [idp.SessionSupportsMigration] functionality
+// Session extends the [oauth.Session] to be able to handle the id_token and to implement the [idp.SessionSupportsMigration] functionality
 type Session struct {
-	*oauth.Session
+	*Provider
+	Code string
+
+	OAuthSession *oauth.Session
+}
+
+// GetAuth implements the [idp.Provider] interface by calling the wrapped [oauth.Session].
+func (s *Session) GetAuth(ctx context.Context) (content string, redirect bool) {
+	return s.oauth().GetAuth(ctx)
 }
 
 // RetrievePreviousID implements the [idp.SessionSupportsMigration] interface by returning the `sub` from the userinfo endpoint
@@ -20,10 +31,57 @@ func (s *Session) RetrievePreviousID() (string, error) {
 	if err != nil {
 		return "", err
 	}
-	req.Header.Set("authorization", s.Tokens.TokenType+" "+s.Tokens.AccessToken)
+	req.Header.Set("authorization", s.oauth().Tokens.TokenType+" "+s.oauth().Tokens.AccessToken)
 	userinfo := new(oidc.UserInfo)
 	if err := httphelper.HttpRequest(s.Provider.HttpClient(), req, &userinfo); err != nil {
 		return "", err
 	}
 	return userinfo.Subject, nil
 }
+
+// FetchUser implements the [idp.Session] interface.
+// It will execute an OAuth 2.0 code exchange if needed to retrieve the access token,
+// call the specified userEndpoint and map the received information into an [idp.User].
+// In case of a specific TenantID as [TenantType] it will additionally extract the id_token and validate it.
+func (s *Session) FetchUser(ctx context.Context) (user idp.User, err error) {
+	user, err = s.oauth().FetchUser(ctx)
+	if err != nil {
+		return nil, err
+	}
+	// since azure will sign the id_token always with the issuer of the application it might differ from
+	// the issuer the auth and token were based on, e.g. when allowing all account types to login,
+	// then the auth endpoint must be `https://login.microsoftonline.com/common/oauth2/v2.0/authorize`
+	// even though the issuer would be like `https://login.microsoftonline.com/d8cdd43f-fd94-4576-8deb-f3bfea72dc2e/v2.0`
+	if s.Provider.tenant == CommonTenant ||
+		s.Provider.tenant == OrganizationsTenant ||
+		s.Provider.tenant == ConsumersTenant {
+		return user, nil
+	}
+	idToken, ok := s.oauth().Tokens.Extra("id_token").(string)
+	if !ok {
+		return user, nil
+	}
+	idTokenVerifier := rp.NewIDTokenVerifier(s.Provider.issuer(), s.Provider.OAuthConfig().ClientID, rp.NewRemoteKeySet(s.Provider.HttpClient(), s.Provider.keysEndpoint()))
+	s.oauth().Tokens.IDTokenClaims, err = rp.VerifyTokens[*oidc.IDTokenClaims](ctx, s.oauth().Tokens.AccessToken, idToken, idTokenVerifier)
+	if err != nil {
+		return nil, err
+	}
+	s.oauth().Tokens.IDToken = idToken
+	return user, nil
+}
+
+// Tokens returns the [oidc.Tokens] of the underlying [oauth.Session].
+func (s *Session) Tokens() *oidc.Tokens[*oidc.IDTokenClaims] {
+	return s.oauth().Tokens
+}
+
+func (s *Session) oauth() *oauth.Session {
+	if s.OAuthSession != nil {
+		return s.OAuthSession
+	}
+	s.OAuthSession = &oauth.Session{
+		Code:     s.Code,
+		Provider: s.Provider.Provider,
+	}
+	return s.OAuthSession
+}

internal/idp/providers/azuread/session_test.go

@@ -247,12 +247,17 @@ func TestSession_FetchUser(t *testing.T) {
 			provider, err := New(tt.fields.name, tt.fields.clientID, tt.fields.clientSecret, tt.fields.redirectURI, tt.fields.scopes, tt.fields.options...)
 			require.NoError(t, err)
 
-			session := &Session{Session: &oauth.Session{
-				AuthURL:  tt.fields.authURL,
+			session := &Session{
+				Provider: provider,
 				Code:     tt.fields.code,
-				Tokens:   tt.fields.tokens,
-				Provider: provider.Provider,
-			}}
+
+				OAuthSession: &oauth.Session{
+					AuthURL:  tt.fields.authURL,
+					Tokens:   tt.fields.tokens,
+					Provider: provider.Provider,
+					Code:     tt.fields.code,
+				},
+			}
 
 			user, err := session.FetchUser(context.Background())
 			if tt.want.err != nil && !tt.want.err(err) {
@@ -392,10 +397,12 @@ func TestSession_RetrievePreviousID(t *testing.T) {
 
 			provider, err := New(tt.fields.name, tt.fields.clientID, tt.fields.clientSecret, tt.fields.redirectURI, tt.fields.scopes)
 			require.NoError(t, err)
-			session := &Session{Session: &oauth.Session{
-				Tokens:   tt.fields.tokens,
-				Provider: provider.Provider,
-			}}
+			session := &Session{
+				Provider: provider,
+				OAuthSession: &oauth.Session{
+					Tokens:   tt.fields.tokens,
+					Provider: provider.Provider,
+				}}
 
 			id, err := session.RetrievePreviousID()
 			if tt.res.err {