package token import ( "encoding/json" "fmt" "io/ioutil" "os" "path/filepath" "github.com/hashicorp/consul/lib/file" ) // Logger used by Store.Load to report warnings. type Logger interface { Warn(msg string, args ...interface{}) } // Config used by Store.Load, which includes tokens and settings for persistence. type Config struct { EnablePersistence bool DataDir string ACLDefaultToken string ACLAgentToken string ACLAgentMasterToken string ACLReplicationToken string EnterpriseConfig } const tokensPath = "acl-tokens.json" // Load tokens from Config and optionally from a persisted file in the cfg.DataDir. // If a token exists in both the persisted file and in the Config a warning will // be logged and the persisted token will be used. // // Failures to load the persisted file will result in loading tokens from the // config before returning the error. func (t *Store) Load(cfg Config, logger Logger) error { t.persistenceLock.RLock() if !cfg.EnablePersistence { t.persistence = nil t.persistenceLock.RUnlock() loadTokens(t, cfg, persistedTokens{}, logger) return nil } defer t.persistenceLock.RUnlock() t.persistence = &fileStore{ filename: filepath.Join(cfg.DataDir, tokensPath), logger: logger, } return t.persistence.load(t, cfg) } // WithPersistenceLock executes f while hold a lock. If f returns a nil error, // the tokens in Store will be persisted to the tokens file. Otherwise no // tokens will be persisted, and the error from f will be returned. // // The lock is held so that the writes are persisted before some other thread // can change the value. func (t *Store) WithPersistenceLock(f func() error) error { t.persistenceLock.Lock() if t.persistence == nil { t.persistenceLock.Unlock() return f() } defer t.persistenceLock.Unlock() return t.persistence.withPersistenceLock(t, f) } type persistedTokens struct { Replication string `json:"replication,omitempty"` AgentMaster string `json:"agent_master,omitempty"` Default string `json:"default,omitempty"` Agent string `json:"agent,omitempty"` } type fileStore struct { filename string logger Logger } func (p *fileStore) load(s *Store, cfg Config) error { tokens, err := readPersistedFromFile(p.filename) if err != nil { p.logger.Warn("unable to load persisted tokens", "error", err) } loadTokens(s, cfg, tokens, p.logger) return err } func loadTokens(s *Store, cfg Config, tokens persistedTokens, logger Logger) { if tokens.Default != "" { s.UpdateUserToken(tokens.Default, TokenSourceAPI) if cfg.ACLDefaultToken != "" { logger.Warn("\"default\" token present in both the configuration and persisted token store, using the persisted token") } } else { s.UpdateUserToken(cfg.ACLDefaultToken, TokenSourceConfig) } if tokens.Agent != "" { s.UpdateAgentToken(tokens.Agent, TokenSourceAPI) if cfg.ACLAgentToken != "" { logger.Warn("\"agent\" token present in both the configuration and persisted token store, using the persisted token") } } else { s.UpdateAgentToken(cfg.ACLAgentToken, TokenSourceConfig) } if tokens.AgentMaster != "" { s.UpdateAgentMasterToken(tokens.AgentMaster, TokenSourceAPI) if cfg.ACLAgentMasterToken != "" { logger.Warn("\"agent_master\" token present in both the configuration and persisted token store, using the persisted token") } } else { s.UpdateAgentMasterToken(cfg.ACLAgentMasterToken, TokenSourceConfig) } if tokens.Replication != "" { s.UpdateReplicationToken(tokens.Replication, TokenSourceAPI) if cfg.ACLReplicationToken != "" { logger.Warn("\"replication\" token present in both the configuration and persisted token store, using the persisted token") } } else { s.UpdateReplicationToken(cfg.ACLReplicationToken, TokenSourceConfig) } loadEnterpriseTokens(s, cfg) } func readPersistedFromFile(filename string) (persistedTokens, error) { tokens := persistedTokens{} buf, err := ioutil.ReadFile(filename) switch { case os.IsNotExist(err): // non-existence is not an error we care about return tokens, nil case err != nil: return tokens, fmt.Errorf("failed reading tokens file %q: %w", filename, err) } if err := json.Unmarshal(buf, &tokens); err != nil { return tokens, fmt.Errorf("failed to decode tokens file %q: %w", filename, err) } return tokens, nil } func (p *fileStore) withPersistenceLock(s *Store, f func() error) error { if err := f(); err != nil { return err } return p.saveToFile(s) } func (p *fileStore) saveToFile(s *Store) error { tokens := persistedTokens{} if tok, source := s.UserTokenAndSource(); tok != "" && source == TokenSourceAPI { tokens.Default = tok } if tok, source := s.AgentTokenAndSource(); tok != "" && source == TokenSourceAPI { tokens.Agent = tok } if tok, source := s.AgentMasterTokenAndSource(); tok != "" && source == TokenSourceAPI { tokens.AgentMaster = tok } if tok, source := s.ReplicationTokenAndSource(); tok != "" && source == TokenSourceAPI { tokens.Replication = tok } data, err := json.Marshal(tokens) if err != nil { p.logger.Warn("failed to persist tokens", "error", err) return fmt.Errorf("Failed to marshal tokens for persistence: %v", err) } if err := file.WriteAtomicWithPerms(p.filename, data, 0700, 0600); err != nil { p.logger.Warn("failed to persist tokens", "error", err) return fmt.Errorf("Failed to persist tokens - %v", err) } return nil }