package main import ( "encoding/json" "flag" "math/rand" "net/http" "strconv" "strings" "time" "github.com/Sirupsen/logrus" "github.com/docker/distribution/context" "github.com/docker/distribution/registry/api/errcode" "github.com/docker/distribution/registry/auth" _ "github.com/docker/distribution/registry/auth/htpasswd" "github.com/docker/libtrust" "github.com/gorilla/mux" ) func main() { var ( issuer = &TokenIssuer{} pkFile string addr string debug bool err error passwdFile string realm string cert string certKey string ) flag.StringVar(&issuer.Issuer, "issuer", "distribution-token-server", "Issuer string for token") flag.StringVar(&pkFile, "key", "", "Private key file") flag.StringVar(&addr, "addr", "localhost:8080", "Address to listen on") flag.BoolVar(&debug, "debug", false, "Debug mode") flag.StringVar(&passwdFile, "passwd", ".htpasswd", "Passwd file") flag.StringVar(&realm, "realm", "", "Authentication realm") flag.StringVar(&cert, "tlscert", "", "Certificate file for TLS") flag.StringVar(&certKey, "tlskey", "", "Certificate key for TLS") flag.Parse() if debug { logrus.SetLevel(logrus.DebugLevel) } if pkFile == "" { issuer.SigningKey, err = libtrust.GenerateECP256PrivateKey() if err != nil { logrus.Fatalf("Error generating private key: %v", err) } logrus.Debugf("Using newly generated key with id %s", issuer.SigningKey.KeyID()) } else { issuer.SigningKey, err = libtrust.LoadKeyFile(pkFile) if err != nil { logrus.Fatalf("Error loading key file %s: %v", pkFile, err) } logrus.Debugf("Loaded private key with id %s", issuer.SigningKey.KeyID()) } if realm == "" { logrus.Fatalf("Must provide realm") } ac, err := auth.GetAccessController("htpasswd", map[string]interface{}{ "realm": realm, "path": passwdFile, }) if err != nil { logrus.Fatalf("Error initializing access controller: %v", err) } // TODO: Make configurable issuer.Expiration = 15 * time.Minute ctx := context.Background() ts := &tokenServer{ issuer: issuer, accessController: ac, refreshCache: map[string]refreshToken{}, } router := mux.NewRouter() router.Path("/token/").Methods("GET").Handler(handlerWithContext(ctx, ts.getToken)) router.Path("/token/").Methods("POST").Handler(handlerWithContext(ctx, ts.postToken)) if cert == "" { err = http.ListenAndServe(addr, router) } else if certKey == "" { logrus.Fatalf("Must provide certficate (-tlscert) and key (-tlskey)") } else { err = http.ListenAndServeTLS(addr, cert, certKey, router) } if err != nil { logrus.Infof("Error serving: %v", err) } } // handlerWithContext wraps the given context-aware handler by setting up the // request context from a base context. func handlerWithContext(ctx context.Context, handler func(context.Context, http.ResponseWriter, *http.Request)) http.Handler { return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { ctx := context.WithRequest(ctx, r) logger := context.GetRequestLogger(ctx) ctx = context.WithLogger(ctx, logger) handler(ctx, w, r) }) } func handleError(ctx context.Context, err error, w http.ResponseWriter) { ctx, w = context.WithResponseWriter(ctx, w) if serveErr := errcode.ServeJSON(w, err); serveErr != nil { context.GetResponseLogger(ctx).Errorf("error sending error response: %v", serveErr) return } context.GetResponseLogger(ctx).Info("application error") } var refreshCharacters = []rune("0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ") const refreshTokenLength = 15 func newRefreshToken() string { s := make([]rune, refreshTokenLength) for i := range s { s[i] = refreshCharacters[rand.Intn(len(refreshCharacters))] } return string(s) } type refreshToken struct { subject string service string } type tokenServer struct { issuer *TokenIssuer accessController auth.AccessController refreshCache map[string]refreshToken } type tokenResponse struct { Token string `json:"access_token"` RefreshToken string `json:"refresh_token,omitempty"` ExpiresIn int `json:"expires_in,omitempty"` } func filterAccessList(ctx context.Context, scope string, requestedAccessList []auth.Access) []auth.Access { if !strings.HasSuffix(scope, "/") { scope = scope + "/" } grantedAccessList := make([]auth.Access, 0, len(requestedAccessList)) for _, access := range requestedAccessList { if access.Type == "repository" { if !strings.HasPrefix(access.Name, scope) { context.GetLogger(ctx).Debugf("Resource scope not allowed: %s", access.Name) continue } } else if access.Type == "registry" { if access.Name != "catalog" { context.GetLogger(ctx).Debugf("Unknown registry resource: %s", access.Name) continue } // TODO: Limit some actions to "admin" users } else { context.GetLogger(ctx).Debugf("Skipping unsupported resource type: %s", access.Type) continue } grantedAccessList = append(grantedAccessList, access) } return grantedAccessList } type acctSubject struct{} func (acctSubject) String() string { return "acctSubject" } type requestedAccess struct{} func (requestedAccess) String() string { return "requestedAccess" } type grantedAccess struct{} func (grantedAccess) String() string { return "grantedAccess" } // getToken handles authenticating the request and authorizing access to the // requested scopes. func (ts *tokenServer) getToken(ctx context.Context, w http.ResponseWriter, r *http.Request) { context.GetLogger(ctx).Info("getToken") params := r.URL.Query() service := params.Get("service") scopeSpecifiers := params["scope"] var offline bool if offlineStr := params.Get("offline_token"); offlineStr != "" { var err error offline, err = strconv.ParseBool(offlineStr) if err != nil { handleError(ctx, ErrorBadTokenOption.WithDetail(err), w) return } } requestedAccessList := ResolveScopeSpecifiers(ctx, scopeSpecifiers) authorizedCtx, err := ts.accessController.Authorized(ctx, requestedAccessList...) if err != nil { challenge, ok := err.(auth.Challenge) if !ok { handleError(ctx, err, w) return } // Get response context. ctx, w = context.WithResponseWriter(ctx, w) challenge.SetHeaders(w) handleError(ctx, errcode.ErrorCodeUnauthorized.WithDetail(challenge.Error()), w) context.GetResponseLogger(ctx).Info("get token authentication challenge") return } ctx = authorizedCtx username := context.GetStringValue(ctx, "auth.user.name") ctx = context.WithValue(ctx, acctSubject{}, username) ctx = context.WithLogger(ctx, context.GetLogger(ctx, acctSubject{})) context.GetLogger(ctx).Info("authenticated client") ctx = context.WithValue(ctx, requestedAccess{}, requestedAccessList) ctx = context.WithLogger(ctx, context.GetLogger(ctx, requestedAccess{})) grantedAccessList := filterAccessList(ctx, username, requestedAccessList) ctx = context.WithValue(ctx, grantedAccess{}, grantedAccessList) ctx = context.WithLogger(ctx, context.GetLogger(ctx, grantedAccess{})) token, err := ts.issuer.CreateJWT(username, service, grantedAccessList) if err != nil { handleError(ctx, err, w) return } context.GetLogger(ctx).Info("authorized client") response := tokenResponse{ Token: token, ExpiresIn: int(ts.issuer.Expiration.Seconds()), } if offline { response.RefreshToken = newRefreshToken() ts.refreshCache[response.RefreshToken] = refreshToken{ subject: username, service: service, } } ctx, w = context.WithResponseWriter(ctx, w) w.Header().Set("Content-Type", "application/json") json.NewEncoder(w).Encode(response) context.GetResponseLogger(ctx).Info("get token complete") } type postTokenResponse struct { Token string `json:"access_token"` Scope string `json:"scope,omitempty"` ExpiresIn int `json:"expires_in,omitempty"` IssuedAt string `json:"issued_at,omitempty"` RefreshToken string `json:"refresh_token,omitempty"` } // postToken handles authenticating the request and authorizing access to the // requested scopes. func (ts *tokenServer) postToken(ctx context.Context, w http.ResponseWriter, r *http.Request) { grantType := r.PostFormValue("grant_type") if grantType == "" { handleError(ctx, ErrorMissingRequiredField.WithDetail("missing grant_type value"), w) return } service := r.PostFormValue("service") if service == "" { handleError(ctx, ErrorMissingRequiredField.WithDetail("missing service value"), w) return } clientID := r.PostFormValue("client_id") if clientID == "" { handleError(ctx, ErrorMissingRequiredField.WithDetail("missing client_id value"), w) return } var offline bool switch r.PostFormValue("access_type") { case "", "online": case "offline": offline = true default: handleError(ctx, ErrorUnsupportedValue.WithDetail("unknown access_type value"), w) return } requestedAccessList := ResolveScopeList(ctx, r.PostFormValue("scope")) var subject string var rToken string switch grantType { case "refresh_token": rToken = r.PostFormValue("refresh_token") if rToken == "" { handleError(ctx, ErrorUnsupportedValue.WithDetail("missing refresh_token value"), w) return } rt, ok := ts.refreshCache[rToken] if !ok || rt.service != service { handleError(ctx, errcode.ErrorCodeUnauthorized.WithDetail("invalid refresh token"), w) return } subject = rt.subject case "password": ca, ok := ts.accessController.(auth.CredentialAuthenticator) if !ok { handleError(ctx, ErrorUnsupportedValue.WithDetail("password grant type not supported"), w) return } subject = r.PostFormValue("username") if subject == "" { handleError(ctx, ErrorUnsupportedValue.WithDetail("missing username value"), w) return } password := r.PostFormValue("password") if password == "" { handleError(ctx, ErrorUnsupportedValue.WithDetail("missing password value"), w) return } if err := ca.AuthenticateUser(subject, password); err != nil { handleError(ctx, errcode.ErrorCodeUnauthorized.WithDetail("invalid credentials"), w) return } default: handleError(ctx, ErrorUnsupportedValue.WithDetail("unknown grant_type value"), w) return } ctx = context.WithValue(ctx, acctSubject{}, subject) ctx = context.WithLogger(ctx, context.GetLogger(ctx, acctSubject{})) context.GetLogger(ctx).Info("authenticated client") ctx = context.WithValue(ctx, requestedAccess{}, requestedAccessList) ctx = context.WithLogger(ctx, context.GetLogger(ctx, requestedAccess{})) grantedAccessList := filterAccessList(ctx, subject, requestedAccessList) ctx = context.WithValue(ctx, grantedAccess{}, grantedAccessList) ctx = context.WithLogger(ctx, context.GetLogger(ctx, grantedAccess{})) token, err := ts.issuer.CreateJWT(subject, service, grantedAccessList) if err != nil { handleError(ctx, err, w) return } context.GetLogger(ctx).Info("authorized client") response := postTokenResponse{ Token: token, ExpiresIn: int(ts.issuer.Expiration.Seconds()), IssuedAt: time.Now().UTC().Format(time.RFC3339), Scope: ToScopeList(grantedAccessList), } if offline { rToken = newRefreshToken() ts.refreshCache[rToken] = refreshToken{ subject: subject, service: service, } } if rToken != "" { response.RefreshToken = rToken } ctx, w = context.WithResponseWriter(ctx, w) w.Header().Set("Content-Type", "application/json") json.NewEncoder(w).Encode(response) context.GetResponseLogger(ctx).Info("post token complete") }