refactor: add ValidateSession gRPC and streamline test setup

- Add ValidateSession gRPC method for proxy-side user validation
- Move group access validation from REST callback to gRPC layer
- Capture user info in access logs via CapturedData mutable pointer
- Create validate_session_test.go for gRPC validation tests
- Simplify auth_callback_integration_test.go to create accounts
  programmatically instead of using SQL file
- SQL test data file now only used by validate_session_test.go

management/internals/shared/grpc/proxy.go

@@ -26,6 +26,7 @@ import (
 	"github.com/netbirdio/netbird/management/internals/modules/reverseproxy"
 	"github.com/netbirdio/netbird/management/internals/modules/reverseproxy/accesslogs"
 	"github.com/netbirdio/netbird/management/internals/modules/reverseproxy/sessionkey"
+	"github.com/netbirdio/netbird/management/server/types"
 	"github.com/netbirdio/netbird/management/server/users"
 	proxyauth "github.com/netbirdio/netbird/proxy/auth"
 	"github.com/netbirdio/netbird/shared/management/proto"
@@ -795,3 +796,143 @@ func (s *ProxyServiceServer) getAccountProxyByDomain(ctx context.Context, accoun
 
 	return nil, fmt.Errorf("reverse proxy not found for domain %s in account %s", domain, accountID)
 }
+
+// ValidateSession validates a session token and checks if the user has access to the domain.
+func (s *ProxyServiceServer) ValidateSession(ctx context.Context, req *proto.ValidateSessionRequest) (*proto.ValidateSessionResponse, error) {
+	domain := req.GetDomain()
+	sessionToken := req.GetSessionToken()
+
+	if domain == "" || sessionToken == "" {
+		return &proto.ValidateSessionResponse{
+			Valid:        false,
+			DeniedReason: "missing domain or session_token",
+		}, nil
+	}
+
+	proxy, err := s.getProxyByDomain(ctx, domain)
+	if err != nil {
+		log.WithFields(log.Fields{
+			"domain": domain,
+			"error":  err.Error(),
+		}).Debug("ValidateSession: proxy not found")
+		return &proto.ValidateSessionResponse{
+			Valid:        false,
+			DeniedReason: "proxy_not_found",
+		}, nil
+	}
+
+	pubKeyBytes, err := base64.StdEncoding.DecodeString(proxy.SessionPublicKey)
+	if err != nil {
+		log.WithFields(log.Fields{
+			"domain": domain,
+			"error":  err.Error(),
+		}).Error("ValidateSession: decode public key")
+		return &proto.ValidateSessionResponse{
+			Valid:        false,
+			DeniedReason: "invalid_proxy_config",
+		}, nil
+	}
+
+	userID, _, err := proxyauth.ValidateSessionJWT(sessionToken, domain, pubKeyBytes)
+	if err != nil {
+		log.WithFields(log.Fields{
+			"domain": domain,
+			"error":  err.Error(),
+		}).Debug("ValidateSession: invalid session token")
+		return &proto.ValidateSessionResponse{
+			Valid:        false,
+			DeniedReason: "invalid_token",
+		}, nil
+	}
+
+	user, err := s.usersManager.GetUser(ctx, userID)
+	if err != nil {
+		log.WithFields(log.Fields{
+			"domain":  domain,
+			"user_id": userID,
+			"error":   err.Error(),
+		}).Debug("ValidateSession: user not found")
+		return &proto.ValidateSessionResponse{
+			Valid:        false,
+			DeniedReason: "user_not_found",
+		}, nil
+	}
+
+	if user.AccountID != proxy.AccountID {
+		log.WithFields(log.Fields{
+			"domain":        domain,
+			"user_id":       userID,
+			"user_account":  user.AccountID,
+			"proxy_account": proxy.AccountID,
+		}).Debug("ValidateSession: user account mismatch")
+		return &proto.ValidateSessionResponse{
+			Valid:        false,
+			DeniedReason: "account_mismatch",
+		}, nil
+	}
+
+	if err := s.checkGroupAccess(proxy, user); err != nil {
+		log.WithFields(log.Fields{
+			"domain":  domain,
+			"user_id": userID,
+			"error":   err.Error(),
+		}).Debug("ValidateSession: access denied")
+		return &proto.ValidateSessionResponse{
+			Valid:        false,
+			UserId:       user.Id,
+			UserEmail:    user.Email,
+			DeniedReason: "not_in_group",
+		}, nil
+	}
+
+	log.WithFields(log.Fields{
+		"domain":  domain,
+		"user_id": userID,
+		"email":   user.Email,
+	}).Debug("ValidateSession: access granted")
+
+	return &proto.ValidateSessionResponse{
+		Valid:     true,
+		UserId:    user.Id,
+		UserEmail: user.Email,
+	}, nil
+}
+
+func (s *ProxyServiceServer) getProxyByDomain(ctx context.Context, domain string) (*reverseproxy.ReverseProxy, error) {
+	proxies, err := s.reverseProxyManager.GetGlobalReverseProxies(ctx)
+	if err != nil {
+		return nil, fmt.Errorf("get reverse proxies: %w", err)
+	}
+
+	for _, proxy := range proxies {
+		if proxy.Domain == domain {
+			return proxy, nil
+		}
+	}
+
+	return nil, fmt.Errorf("reverse proxy not found for domain: %s", domain)
+}
+
+func (s *ProxyServiceServer) checkGroupAccess(proxy *reverseproxy.ReverseProxy, user *types.User) error {
+	if proxy.Auth.BearerAuth == nil || !proxy.Auth.BearerAuth.Enabled {
+		return nil
+	}
+
+	allowedGroups := proxy.Auth.BearerAuth.DistributionGroups
+	if len(allowedGroups) == 0 {
+		return nil
+	}
+
+	allowedSet := make(map[string]bool, len(allowedGroups))
+	for _, groupID := range allowedGroups {
+		allowedSet[groupID] = true
+	}
+
+	for _, groupID := range user.AutoGroups {
+		if allowedSet[groupID] {
+			return nil
+		}
+	}
+
+	return fmt.Errorf("user not in allowed groups")
+}

management/internals/shared/grpc/proxy_group_access_test.go

@@ -68,6 +68,10 @@ func (m *mockReverseProxyManager) GetProxyByID(ctx context.Context, accountID, r
 	return nil, nil
 }
 
+func (m *mockReverseProxyManager) GetProxyIDByTargetID(_ context.Context, _, _ string) (string, error) {
+	return "", nil
+}
+
 type mockUsersManager struct {
 	users map[string]*types.User
 	err   error

management/internals/shared/grpc/validate_session_test.go

@@ -0,0 +1,304 @@
+//go:build integration
+
+package grpc
+
+import (
+	"context"
+	"crypto/ed25519"
+	"crypto/rand"
+	"encoding/base64"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
+	"github.com/netbirdio/netbird/management/internals/modules/reverseproxy"
+	"github.com/netbirdio/netbird/management/internals/modules/reverseproxy/sessionkey"
+	"github.com/netbirdio/netbird/management/server/store"
+	"github.com/netbirdio/netbird/management/server/types"
+	"github.com/netbirdio/netbird/proxy/auth"
+	"github.com/netbirdio/netbird/shared/management/proto"
+)
+
+type validateSessionTestSetup struct {
+	proxyService *ProxyServiceServer
+	store        store.Store
+	cleanup      func()
+}
+
+func setupValidateSessionTest(t *testing.T) *validateSessionTestSetup {
+	t.Helper()
+
+	ctx := context.Background()
+	testStore, storeCleanup, err := store.NewTestStoreFromSQL(ctx, "../../../server/testdata/auth_callback.sql", t.TempDir())
+	require.NoError(t, err)
+
+	proxyManager := &testValidateSessionProxyManager{store: testStore}
+	usersManager := &testValidateSessionUsersManager{store: testStore}
+
+	proxyService := NewProxyServiceServer(nil, NewOneTimeTokenStore(time.Minute), ProxyOIDCConfig{}, nil, usersManager)
+	proxyService.SetProxyManager(proxyManager)
+
+	createTestProxies(t, ctx, testStore)
+
+	return &validateSessionTestSetup{
+		proxyService: proxyService,
+		store:        testStore,
+		cleanup:      storeCleanup,
+	}
+}
+
+func createTestProxies(t *testing.T, ctx context.Context, testStore store.Store) {
+	t.Helper()
+
+	pubKey, privKey := generateSessionKeyPair(t)
+
+	testProxy := &reverseproxy.ReverseProxy{
+		ID:                "testProxyId",
+		AccountID:         "testAccountId",
+		Name:              "Test Proxy",
+		Domain:            "test-proxy.example.com",
+		Enabled:           true,
+		SessionPrivateKey: privKey,
+		SessionPublicKey:  pubKey,
+		Auth: reverseproxy.AuthConfig{
+			BearerAuth: &reverseproxy.BearerAuthConfig{
+				Enabled: true,
+			},
+		},
+	}
+	require.NoError(t, testStore.CreateReverseProxy(ctx, testProxy))
+
+	restrictedProxy := &reverseproxy.ReverseProxy{
+		ID:                "restrictedProxyId",
+		AccountID:         "testAccountId",
+		Name:              "Restricted Proxy",
+		Domain:            "restricted-proxy.example.com",
+		Enabled:           true,
+		SessionPrivateKey: privKey,
+		SessionPublicKey:  pubKey,
+		Auth: reverseproxy.AuthConfig{
+			BearerAuth: &reverseproxy.BearerAuthConfig{
+				Enabled:            true,
+				DistributionGroups: []string{"allowedGroupId"},
+			},
+		},
+	}
+	require.NoError(t, testStore.CreateReverseProxy(ctx, restrictedProxy))
+}
+
+func generateSessionKeyPair(t *testing.T) (string, string) {
+	t.Helper()
+	pub, priv, err := ed25519.GenerateKey(rand.Reader)
+	require.NoError(t, err)
+	return base64.StdEncoding.EncodeToString(pub), base64.StdEncoding.EncodeToString(priv)
+}
+
+func createSessionToken(t *testing.T, privKeyB64, userID, domain string) string {
+	t.Helper()
+	token, err := sessionkey.SignToken(privKeyB64, userID, domain, auth.MethodOIDC, time.Hour)
+	require.NoError(t, err)
+	return token
+}
+
+func TestValidateSession_UserAllowed(t *testing.T) {
+	setup := setupValidateSessionTest(t)
+	defer setup.cleanup()
+
+	proxy, err := setup.store.GetReverseProxyByID(context.Background(), store.LockingStrengthNone, "testAccountId", "testProxyId")
+	require.NoError(t, err)
+
+	token := createSessionToken(t, proxy.SessionPrivateKey, "allowedUserId", "test-proxy.example.com")
+
+	resp, err := setup.proxyService.ValidateSession(context.Background(), &proto.ValidateSessionRequest{
+		Domain:       "test-proxy.example.com",
+		SessionToken: token,
+	})
+
+	require.NoError(t, err)
+	assert.True(t, resp.Valid, "User should be allowed access")
+	assert.Equal(t, "allowedUserId", resp.UserId)
+	assert.Empty(t, resp.DeniedReason)
+}
+
+func TestValidateSession_UserNotInAllowedGroup(t *testing.T) {
+	setup := setupValidateSessionTest(t)
+	defer setup.cleanup()
+
+	proxy, err := setup.store.GetReverseProxyByID(context.Background(), store.LockingStrengthNone, "testAccountId", "restrictedProxyId")
+	require.NoError(t, err)
+
+	token := createSessionToken(t, proxy.SessionPrivateKey, "nonGroupUserId", "restricted-proxy.example.com")
+
+	resp, err := setup.proxyService.ValidateSession(context.Background(), &proto.ValidateSessionRequest{
+		Domain:       "restricted-proxy.example.com",
+		SessionToken: token,
+	})
+
+	require.NoError(t, err)
+	assert.False(t, resp.Valid, "User not in group should be denied")
+	assert.Equal(t, "not_in_group", resp.DeniedReason)
+	assert.Equal(t, "nonGroupUserId", resp.UserId)
+}
+
+func TestValidateSession_UserInDifferentAccount(t *testing.T) {
+	setup := setupValidateSessionTest(t)
+	defer setup.cleanup()
+
+	proxy, err := setup.store.GetReverseProxyByID(context.Background(), store.LockingStrengthNone, "testAccountId", "testProxyId")
+	require.NoError(t, err)
+
+	token := createSessionToken(t, proxy.SessionPrivateKey, "otherAccountUserId", "test-proxy.example.com")
+
+	resp, err := setup.proxyService.ValidateSession(context.Background(), &proto.ValidateSessionRequest{
+		Domain:       "test-proxy.example.com",
+		SessionToken: token,
+	})
+
+	require.NoError(t, err)
+	assert.False(t, resp.Valid, "User in different account should be denied")
+	assert.Equal(t, "account_mismatch", resp.DeniedReason)
+}
+
+func TestValidateSession_UserNotFound(t *testing.T) {
+	setup := setupValidateSessionTest(t)
+	defer setup.cleanup()
+
+	proxy, err := setup.store.GetReverseProxyByID(context.Background(), store.LockingStrengthNone, "testAccountId", "testProxyId")
+	require.NoError(t, err)
+
+	token := createSessionToken(t, proxy.SessionPrivateKey, "nonExistentUserId", "test-proxy.example.com")
+
+	resp, err := setup.proxyService.ValidateSession(context.Background(), &proto.ValidateSessionRequest{
+		Domain:       "test-proxy.example.com",
+		SessionToken: token,
+	})
+
+	require.NoError(t, err)
+	assert.False(t, resp.Valid, "Non-existent user should be denied")
+	assert.Equal(t, "user_not_found", resp.DeniedReason)
+}
+
+func TestValidateSession_ProxyNotFound(t *testing.T) {
+	setup := setupValidateSessionTest(t)
+	defer setup.cleanup()
+
+	proxy, err := setup.store.GetReverseProxyByID(context.Background(), store.LockingStrengthNone, "testAccountId", "testProxyId")
+	require.NoError(t, err)
+
+	token := createSessionToken(t, proxy.SessionPrivateKey, "allowedUserId", "unknown-proxy.example.com")
+
+	resp, err := setup.proxyService.ValidateSession(context.Background(), &proto.ValidateSessionRequest{
+		Domain:       "unknown-proxy.example.com",
+		SessionToken: token,
+	})
+
+	require.NoError(t, err)
+	assert.False(t, resp.Valid, "Unknown proxy should be denied")
+	assert.Equal(t, "proxy_not_found", resp.DeniedReason)
+}
+
+func TestValidateSession_InvalidToken(t *testing.T) {
+	setup := setupValidateSessionTest(t)
+	defer setup.cleanup()
+
+	resp, err := setup.proxyService.ValidateSession(context.Background(), &proto.ValidateSessionRequest{
+		Domain:       "test-proxy.example.com",
+		SessionToken: "invalid-token",
+	})
+
+	require.NoError(t, err)
+	assert.False(t, resp.Valid, "Invalid token should be denied")
+	assert.Equal(t, "invalid_token", resp.DeniedReason)
+}
+
+func TestValidateSession_MissingDomain(t *testing.T) {
+	setup := setupValidateSessionTest(t)
+	defer setup.cleanup()
+
+	resp, err := setup.proxyService.ValidateSession(context.Background(), &proto.ValidateSessionRequest{
+		SessionToken: "some-token",
+	})
+
+	require.NoError(t, err)
+	assert.False(t, resp.Valid)
+	assert.Contains(t, resp.DeniedReason, "missing")
+}
+
+func TestValidateSession_MissingToken(t *testing.T) {
+	setup := setupValidateSessionTest(t)
+	defer setup.cleanup()
+
+	resp, err := setup.proxyService.ValidateSession(context.Background(), &proto.ValidateSessionRequest{
+		Domain: "test-proxy.example.com",
+	})
+
+	require.NoError(t, err)
+	assert.False(t, resp.Valid)
+	assert.Contains(t, resp.DeniedReason, "missing")
+}
+
+type testValidateSessionProxyManager struct {
+	store store.Store
+}
+
+func (m *testValidateSessionProxyManager) GetAllReverseProxies(_ context.Context, _, _ string) ([]*reverseproxy.ReverseProxy, error) {
+	return nil, nil
+}
+
+func (m *testValidateSessionProxyManager) GetReverseProxy(_ context.Context, _, _, _ string) (*reverseproxy.ReverseProxy, error) {
+	return nil, nil
+}
+
+func (m *testValidateSessionProxyManager) CreateReverseProxy(_ context.Context, _, _ string, _ *reverseproxy.ReverseProxy) (*reverseproxy.ReverseProxy, error) {
+	return nil, nil
+}
+
+func (m *testValidateSessionProxyManager) UpdateReverseProxy(_ context.Context, _, _ string, _ *reverseproxy.ReverseProxy) (*reverseproxy.ReverseProxy, error) {
+	return nil, nil
+}
+
+func (m *testValidateSessionProxyManager) DeleteReverseProxy(_ context.Context, _, _, _ string) error {
+	return nil
+}
+
+func (m *testValidateSessionProxyManager) SetCertificateIssuedAt(_ context.Context, _, _ string) error {
+	return nil
+}
+
+func (m *testValidateSessionProxyManager) SetStatus(_ context.Context, _, _ string, _ reverseproxy.ProxyStatus) error {
+	return nil
+}
+
+func (m *testValidateSessionProxyManager) ReloadAllReverseProxiesForAccount(_ context.Context, _ string) error {
+	return nil
+}
+
+func (m *testValidateSessionProxyManager) ReloadReverseProxy(_ context.Context, _, _ string) error {
+	return nil
+}
+
+func (m *testValidateSessionProxyManager) GetGlobalReverseProxies(ctx context.Context) ([]*reverseproxy.ReverseProxy, error) {
+	return m.store.GetReverseProxies(ctx, store.LockingStrengthNone)
+}
+
+func (m *testValidateSessionProxyManager) GetProxyByID(ctx context.Context, accountID, proxyID string) (*reverseproxy.ReverseProxy, error) {
+	return m.store.GetReverseProxyByID(ctx, store.LockingStrengthNone, accountID, proxyID)
+}
+
+func (m *testValidateSessionProxyManager) GetAccountReverseProxies(ctx context.Context, accountID string) ([]*reverseproxy.ReverseProxy, error) {
+	return m.store.GetAccountReverseProxies(ctx, store.LockingStrengthNone, accountID)
+}
+
+func (m *testValidateSessionProxyManager) GetProxyIDByTargetID(_ context.Context, _, _ string) (string, error) {
+	return "", nil
+}
+
+type testValidateSessionUsersManager struct {
+	store store.Store
+}
+
+func (m *testValidateSessionUsersManager) GetUser(ctx context.Context, userID string) (*types.User, error) {
+	return m.store.GetUserByUserID(ctx, store.LockingStrengthNone, userID)
+}