[management, reverse proxy] Add reverse proxy feature (#5291)

* implement reverse proxy --------- Co-authored-by: Alisdair MacLeod <git@alisdairmacleod.co.uk> Co-authored-by: mlsmaycon <mlsmaycon@gmail.com> Co-authored-by: Eduard Gert <kontakt@eduardgert.de> Co-authored-by: Viktor Liu <viktor@netbird.io> Co-authored-by: Diego Noguês <diego.sure@gmail.com> Co-authored-by: Diego Noguês <49420+diegocn@users.noreply.github.com> Co-authored-by: Bethuel Mmbaga <bethuelmbaga12@gmail.com> Co-authored-by: Zoltan Papp <zoltan.pmail@gmail.com> Co-authored-by: Ashley Mensah <ashleyamo982@gmail.com>
2026-10-27 23:09:08 +01:00 · 2026-02-13 19:37:43 +01:00
parent edce11b34d
commit f53155562f
225 changed files with 35513 additions and 235 deletions
@@ -0,0 +1,364 @@
+package auth
+
+import (
+	"context"
+	"crypto/ed25519"
+	"encoding/base64"
+	"fmt"
+	"net"
+	"net/http"
+	"net/url"
+	"sync"
+	"time"
+
+	log "github.com/sirupsen/logrus"
+	"google.golang.org/grpc"
+
+	"github.com/netbirdio/netbird/proxy/auth"
+	"github.com/netbirdio/netbird/proxy/internal/proxy"
+	"github.com/netbirdio/netbird/proxy/internal/types"
+	"github.com/netbirdio/netbird/proxy/web"
+	"github.com/netbirdio/netbird/shared/management/proto"
+)
+
+type authenticator interface {
+	Authenticate(ctx context.Context, in *proto.AuthenticateRequest, opts ...grpc.CallOption) (*proto.AuthenticateResponse, error)
+}
+
+// SessionValidator validates session tokens and checks user access permissions.
+type SessionValidator interface {
+	ValidateSession(ctx context.Context, in *proto.ValidateSessionRequest, opts ...grpc.CallOption) (*proto.ValidateSessionResponse, error)
+}
+
+// Scheme defines an authentication mechanism for a domain.
+type Scheme interface {
+	Type() auth.Method
+	// Authenticate checks the request and determines whether it represents
+	// an authenticated user. An empty token indicates an unauthenticated
+	// request; optionally, promptData may be returned for the login UI.
+	// An error indicates an infrastructure failure (e.g. gRPC unavailable).
+	Authenticate(*http.Request) (token string, promptData string, err error)
+}
+
+type DomainConfig struct {
+	Schemes           []Scheme
+	SessionPublicKey  ed25519.PublicKey
+	SessionExpiration time.Duration
+	AccountID         string
+	ServiceID         string
+}
+
+type validationResult struct {
+	UserID       string
+	Valid        bool
+	DeniedReason string
+}
+
+type Middleware struct {
+	domainsMux       sync.RWMutex
+	domains          map[string]DomainConfig
+	logger           *log.Logger
+	sessionValidator SessionValidator
+}
+
+// NewMiddleware creates a new authentication middleware.
+// The sessionValidator is optional; if nil, OIDC session tokens will be validated
+// locally without group access checks.
+func NewMiddleware(logger *log.Logger, sessionValidator SessionValidator) *Middleware {
+	if logger == nil {
+		logger = log.StandardLogger()
+	}
+	return &Middleware{
+		domains:          make(map[string]DomainConfig),
+		logger:           logger,
+		sessionValidator: sessionValidator,
+	}
+}
+
+// Protect applies authentication middleware to the passed handler.
+// For each incoming request it will be checked against the middleware's
+// internal list of protected domains.
+// If the Host domain in the inbound request is not present, then it will
+// simply be passed through.
+// However, if the Host domain is present, then the specified authentication
+// schemes for that domain will be applied to the request.
+// In the event that no authentication schemes are defined for the domain,
+// then the request will also be simply passed through.
+func (mw *Middleware) Protect(next http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		host, _, err := net.SplitHostPort(r.Host)
+		if err != nil {
+			host = r.Host
+		}
+
+		config, exists := mw.getDomainConfig(host)
+		mw.logger.Debugf("checking authentication for host: %s, exists: %t", host, exists)
+
+		// Domains that are not configured here or have no authentication schemes applied should simply pass through.
+		if !exists || len(config.Schemes) == 0 {
+			next.ServeHTTP(w, r)
+			return
+		}
+
+		// Set account and service IDs in captured data for access logging.
+		setCapturedIDs(r, config)
+
+		if mw.handleOAuthCallbackError(w, r) {
+			return
+		}
+
+		if mw.forwardWithSessionCookie(w, r, host, config, next) {
+			return
+		}
+
+		mw.authenticateWithSchemes(w, r, host, config)
+	})
+}
+
+func (mw *Middleware) getDomainConfig(host string) (DomainConfig, bool) {
+	mw.domainsMux.RLock()
+	defer mw.domainsMux.RUnlock()
+	config, exists := mw.domains[host]
+	return config, exists
+}
+
+func setCapturedIDs(r *http.Request, config DomainConfig) {
+	if cd := proxy.CapturedDataFromContext(r.Context()); cd != nil {
+		cd.SetAccountId(types.AccountID(config.AccountID))
+		cd.SetServiceId(config.ServiceID)
+	}
+}
+
+// handleOAuthCallbackError checks for error query parameters from an OAuth
+// callback and renders the access denied page if present.
+func (mw *Middleware) handleOAuthCallbackError(w http.ResponseWriter, r *http.Request) bool {
+	errCode := r.URL.Query().Get("error")
+	if errCode == "" {
+		return false
+	}
+
+	var requestID string
+	if cd := proxy.CapturedDataFromContext(r.Context()); cd != nil {
+		cd.SetOrigin(proxy.OriginAuth)
+		cd.SetAuthMethod(auth.MethodOIDC.String())
+		requestID = cd.GetRequestID()
+	}
+	errDesc := r.URL.Query().Get("error_description")
+	if errDesc == "" {
+		errDesc = "An error occurred during authentication"
+	}
+	web.ServeAccessDeniedPage(w, r, http.StatusForbidden, "Access Denied", errDesc, requestID)
+	return true
+}
+
+// forwardWithSessionCookie checks for a valid session cookie and, if found,
+// sets the user identity on the request context and forwards to the next handler.
+func (mw *Middleware) forwardWithSessionCookie(w http.ResponseWriter, r *http.Request, host string, config DomainConfig, next http.Handler) bool {
+	cookie, err := r.Cookie(auth.SessionCookieName)
+	if err != nil {
+		return false
+	}
+	userID, method, err := auth.ValidateSessionJWT(cookie.Value, host, config.SessionPublicKey)
+	if err != nil {
+		return false
+	}
+	if cd := proxy.CapturedDataFromContext(r.Context()); cd != nil {
+		cd.SetUserID(userID)
+		cd.SetAuthMethod(method)
+	}
+	next.ServeHTTP(w, r)
+	return true
+}
+
+// authenticateWithSchemes tries each configured auth scheme in order.
+// On success it sets a session cookie and redirects; on failure it renders the login page.
+func (mw *Middleware) authenticateWithSchemes(w http.ResponseWriter, r *http.Request, host string, config DomainConfig) {
+	methods := make(map[string]string)
+	var attemptedMethod string
+
+	for _, scheme := range config.Schemes {
+		token, promptData, err := scheme.Authenticate(r)
+		if err != nil {
+			mw.logger.WithField("scheme", scheme.Type().String()).Warnf("authentication infrastructure error: %v", err)
+			if cd := proxy.CapturedDataFromContext(r.Context()); cd != nil {
+				cd.SetOrigin(proxy.OriginAuth)
+			}
+			http.Error(w, "authentication service unavailable", http.StatusBadGateway)
+			return
+		}
+
+		// Track if credentials were submitted but auth failed
+		if token == "" && wasCredentialSubmitted(r, scheme.Type()) {
+			attemptedMethod = scheme.Type().String()
+		}
+
+		if token != "" {
+			mw.handleAuthenticatedToken(w, r, host, token, config, scheme)
+			return
+		}
+		methods[scheme.Type().String()] = promptData
+	}
+
+	if cd := proxy.CapturedDataFromContext(r.Context()); cd != nil {
+		cd.SetOrigin(proxy.OriginAuth)
+		if attemptedMethod != "" {
+			cd.SetAuthMethod(attemptedMethod)
+		}
+	}
+	web.ServeHTTP(w, r, map[string]any{"methods": methods}, http.StatusUnauthorized)
+}
+
+// handleAuthenticatedToken validates the token, handles denied access, and on
+// success sets a session cookie and redirects to the original URL.
+func (mw *Middleware) handleAuthenticatedToken(w http.ResponseWriter, r *http.Request, host, token string, config DomainConfig, scheme Scheme) {
+	result, err := mw.validateSessionToken(r.Context(), host, token, config.SessionPublicKey, scheme.Type())
+	if err != nil {
+		if cd := proxy.CapturedDataFromContext(r.Context()); cd != nil {
+			cd.SetOrigin(proxy.OriginAuth)
+			cd.SetAuthMethod(scheme.Type().String())
+		}
+		http.Error(w, err.Error(), http.StatusBadRequest)
+		return
+	}
+
+	if !result.Valid {
+		var requestID string
+		if cd := proxy.CapturedDataFromContext(r.Context()); cd != nil {
+			cd.SetOrigin(proxy.OriginAuth)
+			cd.SetUserID(result.UserID)
+			cd.SetAuthMethod(scheme.Type().String())
+			requestID = cd.GetRequestID()
+		}
+		web.ServeAccessDeniedPage(w, r, http.StatusForbidden, "Access Denied", "You are not authorized to access this service", requestID)
+		return
+	}
+
+	expiration := config.SessionExpiration
+	if expiration == 0 {
+		expiration = auth.DefaultSessionExpiry
+	}
+	http.SetCookie(w, &http.Cookie{
+		Name:     auth.SessionCookieName,
+		Value:    token,
+		HttpOnly: true,
+		Secure:   true,
+		SameSite: http.SameSiteLaxMode,
+		MaxAge:   int(expiration.Seconds()),
+	})
+
+	// Redirect instead of forwarding the auth POST to the backend.
+	// The browser will follow with a GET carrying the new session cookie.
+	if cd := proxy.CapturedDataFromContext(r.Context()); cd != nil {
+		cd.SetOrigin(proxy.OriginAuth)
+		cd.SetUserID(result.UserID)
+		cd.SetAuthMethod(scheme.Type().String())
+	}
+	redirectURL := stripSessionTokenParam(r.URL)
+	http.Redirect(w, r, redirectURL, http.StatusSeeOther)
+}
+
+// wasCredentialSubmitted checks if credentials were submitted for the given auth method.
+func wasCredentialSubmitted(r *http.Request, method auth.Method) bool {
+	switch method {
+	case auth.MethodPIN:
+		return r.FormValue("pin") != ""
+	case auth.MethodPassword:
+		return r.FormValue("password") != ""
+	case auth.MethodOIDC:
+		return r.URL.Query().Get("session_token") != ""
+	}
+	return false
+}
+
+// AddDomain registers authentication schemes for the given domain.
+// If schemes are provided, a valid session public key is required to sign/verify
+// session JWTs. Returns an error if the key is missing or invalid.
+// Callers must not serve the domain if this returns an error, to avoid
+// exposing an unauthenticated service.
+func (mw *Middleware) AddDomain(domain string, schemes []Scheme, publicKeyB64 string, expiration time.Duration, accountID, serviceID string) error {
+	if len(schemes) == 0 {
+		mw.domainsMux.Lock()
+		defer mw.domainsMux.Unlock()
+		mw.domains[domain] = DomainConfig{
+			AccountID: accountID,
+			ServiceID: serviceID,
+		}
+		return nil
+	}
+
+	pubKeyBytes, err := base64.StdEncoding.DecodeString(publicKeyB64)
+	if err != nil {
+		return fmt.Errorf("decode session public key for domain %s: %w", domain, err)
+	}
+	if len(pubKeyBytes) != ed25519.PublicKeySize {
+		return fmt.Errorf("invalid session public key size for domain %s: got %d, want %d", domain, len(pubKeyBytes), ed25519.PublicKeySize)
+	}
+
+	mw.domainsMux.Lock()
+	defer mw.domainsMux.Unlock()
+	mw.domains[domain] = DomainConfig{
+		Schemes:           schemes,
+		SessionPublicKey:  pubKeyBytes,
+		SessionExpiration: expiration,
+		AccountID:         accountID,
+		ServiceID:         serviceID,
+	}
+	return nil
+}
+
+func (mw *Middleware) RemoveDomain(domain string) {
+	mw.domainsMux.Lock()
+	defer mw.domainsMux.Unlock()
+	delete(mw.domains, domain)
+}
+
+// validateSessionToken validates a session token, optionally checking group access via gRPC.
+// For OIDC tokens with a configured validator, it calls ValidateSession to check group access.
+// For other auth methods (PIN, password), it validates the JWT locally.
+// Returns a validationResult with user ID and validity status, or error for invalid tokens.
+func (mw *Middleware) validateSessionToken(ctx context.Context, host, token string, publicKey ed25519.PublicKey, method auth.Method) (*validationResult, error) {
+	// For OIDC with a session validator, call the gRPC service to check group access
+	if method == auth.MethodOIDC && mw.sessionValidator != nil {
+		resp, err := mw.sessionValidator.ValidateSession(ctx, &proto.ValidateSessionRequest{
+			Domain:       host,
+			SessionToken: token,
+		})
+		if err != nil {
+			mw.logger.WithError(err).Error("ValidateSession gRPC call failed")
+			return nil, fmt.Errorf("session validation failed")
+		}
+		if !resp.Valid {
+			mw.logger.WithFields(log.Fields{
+				"domain":        host,
+				"denied_reason": resp.DeniedReason,
+				"user_id":       resp.UserId,
+			}).Debug("Session validation denied")
+			return &validationResult{
+				UserID:       resp.UserId,
+				Valid:        false,
+				DeniedReason: resp.DeniedReason,
+			}, nil
+		}
+		return &validationResult{UserID: resp.UserId, Valid: true}, nil
+	}
+
+	// For non-OIDC methods or when no validator is configured, validate JWT locally
+	userID, _, err := auth.ValidateSessionJWT(token, host, publicKey)
+	if err != nil {
+		return nil, err
+	}
+	return &validationResult{UserID: userID, Valid: true}, nil
+}
+
+// stripSessionTokenParam returns the request URI with the session_token query
+// parameter removed so it doesn't linger in the browser's address bar or history.
+func stripSessionTokenParam(u *url.URL) string {
+	q := u.Query()
+	if !q.Has("session_token") {
+		return u.RequestURI()
+	}
+	q.Del("session_token")
+	clean := *u
+	clean.RawQuery = q.Encode()
+	return clean.RequestURI()
+}