package auth import ( "context" "crypto/ed25519" "crypto/rand" "database/sql" "encoding/base64" "encoding/json" "errors" "fmt" "net/http" "os" "strings" "time" "github.com/ClusterCockpit/cc-backend/log" sq "github.com/Masterminds/squirrel" "github.com/golang-jwt/jwt/v4" "github.com/gorilla/sessions" "github.com/jmoiron/sqlx" "golang.org/x/crypto/bcrypt" ) // Only Username and Roles will always be filled in when returned by `GetUser`. // If Name and Email is needed as well, use auth.FetchUser(), which does a database // query for all fields. type User struct { Username string Password string Name string Roles []string ViaLdap bool Email string } const ( RoleAdmin string = "admin" RoleApi string = "api" RoleUser string = "user" ) func (u *User) HasRole(role string) bool { for _, r := range u.Roles { if r == role { return true } } return false } type ContextKey string const ContextUserKey ContextKey = "user" type Authentication struct { db *sqlx.DB sessionStore *sessions.CookieStore jwtPublicKey ed25519.PublicKey jwtPrivateKey ed25519.PrivateKey ldapConfig *LdapConfig ldapSyncUserPassword string // If zero, tokens/sessions do not expire. SessionMaxAge time.Duration JwtMaxAge time.Duration } func (auth *Authentication) Init(db *sqlx.DB, ldapConfig *LdapConfig) error { auth.db = db _, err := db.Exec(` CREATE TABLE IF NOT EXISTS user ( username varchar(255) PRIMARY KEY, password varchar(255) DEFAULT NULL, ldap tinyint DEFAULT 0, name varchar(255) DEFAULT NULL, roles varchar(255) DEFAULT NULL, email varchar(255) DEFAULT NULL);`) if err != nil { return err } sessKey := os.Getenv("SESSION_KEY") if sessKey == "" { log.Warn("environment variable 'SESSION_KEY' not set (will use non-persistent random key)") bytes := make([]byte, 32) if _, err := rand.Read(bytes); err != nil { return err } auth.sessionStore = sessions.NewCookieStore(bytes) } else { bytes, err := base64.StdEncoding.DecodeString(sessKey) if err != nil { return err } auth.sessionStore = sessions.NewCookieStore(bytes) } pubKey, privKey := os.Getenv("JWT_PUBLIC_KEY"), os.Getenv("JWT_PRIVATE_KEY") if pubKey == "" || privKey == "" { log.Warn("environment variables 'JWT_PUBLIC_KEY' or 'JWT_PRIVATE_KEY' not set (token based authentication will not work)") } else { bytes, err := base64.StdEncoding.DecodeString(pubKey) if err != nil { return err } auth.jwtPublicKey = ed25519.PublicKey(bytes) bytes, err = base64.StdEncoding.DecodeString(privKey) if err != nil { return err } auth.jwtPrivateKey = ed25519.PrivateKey(bytes) } if ldapConfig != nil { auth.ldapConfig = ldapConfig if err := auth.initLdap(); err != nil { return err } } return nil } // arg must be formated like this: ":[admin|api|]:" func (auth *Authentication) AddUser(arg string) error { parts := strings.SplitN(arg, ":", 3) if len(parts) != 3 || len(parts[0]) == 0 { return errors.New("invalid argument format") } password := "" if len(parts[2]) > 0 { bytes, err := bcrypt.GenerateFromPassword([]byte(parts[2]), bcrypt.DefaultCost) if err != nil { return err } password = string(bytes) } roles := []string{} for _, role := range strings.Split(parts[1], ",") { if len(role) == 0 { continue } else if role == RoleAdmin || role == RoleApi || role == RoleUser { roles = append(roles, role) } else { return fmt.Errorf("invalid user role: %#v", role) } } rolesJson, _ := json.Marshal(roles) _, err := sq.Insert("user").Columns("username", "password", "roles").Values(parts[0], password, string(rolesJson)).RunWith(auth.db).Exec() if err != nil { return err } log.Infof("new user %#v added (roles: %s)", parts[0], roles) return nil } func (auth *Authentication) DelUser(username string) error { _, err := auth.db.Exec(`DELETE FROM user WHERE user.username = ?`, username) return err } func (auth *Authentication) FetchUser(username string) (*User, error) { user := &User{Username: username} var hashedPassword, name, rawRoles, email sql.NullString if err := sq.Select("password", "ldap", "name", "roles", "email").From("user"). Where("user.username = ?", username).RunWith(auth.db). QueryRow().Scan(&hashedPassword, &user.ViaLdap, &name, &rawRoles, &email); err != nil { return nil, fmt.Errorf("user '%s' not found (%s)", username, err.Error()) } user.Password = hashedPassword.String user.Name = name.String user.Email = email.String if rawRoles.Valid { if err := json.Unmarshal([]byte(rawRoles.String), &user.Roles); err != nil { return nil, err } } return user, nil } // Handle a POST request that should log the user in, starting a new session. func (auth *Authentication) Login(onsuccess http.Handler, onfailure func(rw http.ResponseWriter, r *http.Request, loginErr error)) http.Handler { return http.HandlerFunc(func(rw http.ResponseWriter, r *http.Request) { username, password := r.FormValue("username"), r.FormValue("password") user, err := auth.FetchUser(username) if err == nil && user.ViaLdap && auth.ldapConfig != nil { err = auth.loginViaLdap(user, password) } else if err == nil && !user.ViaLdap && user.Password != "" { if e := bcrypt.CompareHashAndPassword([]byte(user.Password), []byte(password)); e != nil { err = fmt.Errorf("user '%s' provided the wrong password (%s)", username, e.Error()) } } else { err = errors.New("could not authenticate user") } if err != nil { log.Warnf("login of user %#v failed: %s", username, err.Error()) onfailure(rw, r, err) return } session, err := auth.sessionStore.New(r, "session") if err != nil { log.Errorf("session creation failed: %s", err.Error()) http.Error(rw, err.Error(), http.StatusInternalServerError) return } if auth.SessionMaxAge != 0 { session.Options.MaxAge = int(auth.SessionMaxAge.Seconds()) } session.Values["username"] = user.Username session.Values["roles"] = user.Roles if err := auth.sessionStore.Save(r, rw, session); err != nil { log.Errorf("session save failed: %s", err.Error()) http.Error(rw, err.Error(), http.StatusInternalServerError) return } log.Infof("login successfull: user: %#v (roles: %v)", user.Username, user.Roles) ctx := context.WithValue(r.Context(), ContextUserKey, user) onsuccess.ServeHTTP(rw, r.WithContext(ctx)) }) } var ErrTokenInvalid error = errors.New("invalid token") func (auth *Authentication) authViaToken(r *http.Request) (*User, error) { if auth.jwtPublicKey == nil { return nil, nil } rawtoken := r.Header.Get("X-Auth-Token") if rawtoken == "" { rawtoken = r.Header.Get("Authorization") prefix := "Bearer " if !strings.HasPrefix(rawtoken, prefix) { return nil, nil } rawtoken = rawtoken[len(prefix):] } token, err := jwt.Parse(rawtoken, func(t *jwt.Token) (interface{}, error) { if t.Method != jwt.SigningMethodEdDSA { return nil, errors.New("only Ed25519/EdDSA supported") } return auth.jwtPublicKey, nil }) if err != nil { return nil, err } if err := token.Claims.Valid(); err != nil { return nil, err } claims := token.Claims.(jwt.MapClaims) sub, _ := claims["sub"].(string) var roles []string if rawroles, ok := claims["roles"].([]interface{}); ok { for _, rr := range rawroles { if r, ok := rr.(string); ok { roles = append(roles, r) } } } // TODO: Check if sub is still a valid user! return &User{ Username: sub, Roles: roles, }, nil } // Authenticate the user and put a User object in the // context of the request. If authentication fails, // do not continue but send client to the login screen. func (auth *Authentication) Auth(onsuccess http.Handler, onfailure func(rw http.ResponseWriter, r *http.Request, authErr error)) http.Handler { return http.HandlerFunc(func(rw http.ResponseWriter, r *http.Request) { user, err := auth.authViaToken(r) if err != nil { log.Warnf("authentication failed: %s", err.Error()) http.Error(rw, err.Error(), http.StatusUnauthorized) return } if user != nil { // Successfull authentication using a token ctx := context.WithValue(r.Context(), ContextUserKey, user) onsuccess.ServeHTTP(rw, r.WithContext(ctx)) return } session, err := auth.sessionStore.Get(r, "session") if err != nil { // sessionStore.Get will return a new session if no current one is attached to this request. http.Error(rw, err.Error(), http.StatusInternalServerError) return } if session.IsNew { log.Warn("authentication failed: no session or jwt found") onfailure(rw, r, errors.New("no valid session or JWT provided")) return } username, _ := session.Values["username"].(string) roles, _ := session.Values["roles"].([]string) ctx := context.WithValue(r.Context(), ContextUserKey, &User{ Username: username, Roles: roles, }) onsuccess.ServeHTTP(rw, r.WithContext(ctx)) }) } // Generate a new JWT that can be used for authentication func (auth *Authentication) ProvideJWT(user *User) (string, error) { if auth.jwtPrivateKey == nil { return "", errors.New("environment variable 'JWT_PRIVATE_KEY' not set") } claims := jwt.MapClaims{ "sub": user.Username, "roles": user.Roles, } if auth.JwtMaxAge != 0 { claims["exp"] = time.Now().Add(auth.JwtMaxAge).Unix() } tok := jwt.NewWithClaims(jwt.SigningMethodEdDSA, claims) return tok.SignedString(auth.jwtPrivateKey) } func GetUser(ctx context.Context) *User { x := ctx.Value(ContextUserKey) if x == nil { return nil } return x.(*User) } // Clears the session cookie func (auth *Authentication) Logout(onsuccess http.Handler) http.Handler { return http.HandlerFunc(func(rw http.ResponseWriter, r *http.Request) { session, err := auth.sessionStore.Get(r, "session") if err != nil { http.Error(rw, err.Error(), http.StatusInternalServerError) return } if !session.IsNew { session.Options.MaxAge = -1 if err := auth.sessionStore.Save(r, rw, session); err != nil { http.Error(rw, err.Error(), http.StatusInternalServerError) return } } onsuccess.ServeHTTP(rw, r) }) }