package stfe import ( "context" "fmt" "time" "net/http" "github.com/golang/glog" "github.com/google/trillian" ) // handler implements the http.Handler interface, and contains a reference // to an STFE server instance as well as a function that uses it. type handler struct { instance *Instance // STFE server instance endpoint string // e.g., add-entry method string // e.g., GET handler func(context.Context, *Instance, http.ResponseWriter, *http.Request) (int, error) } func (a handler) ServeHTTP(w http.ResponseWriter, r *http.Request) { // export prometheus metrics var now time.Time = time.Now() var statusCode int defer func() { rspcnt.Inc(a.instance.LogParameters.id(), a.endpoint, fmt.Sprintf("%d", statusCode)) latency.Observe(time.Now().Sub(now).Seconds(), a.instance.LogParameters.id(), a.endpoint, fmt.Sprintf("%d", statusCode)) }() reqcnt.Inc(a.instance.LogParameters.id(), a.endpoint) ctx, cancel := context.WithDeadline(r.Context(), now.Add(a.instance.Deadline)) defer cancel() if r.Method != a.method { glog.Warningf("%s: got HTTP %s, wanted HTTP %s", a.instance.LogParameters.Prefix+a.endpoint, r.Method, a.method) a.sendHTTPError(w, http.StatusMethodNotAllowed, fmt.Errorf("method not allowed: %s", r.Method)) return } statusCode, err := a.handler(ctx, a.instance, w, r) if err != nil { glog.Warningf("handler error %s/%s: %v", a.instance.LogParameters.Prefix, a.endpoint, err) a.sendHTTPError(w, statusCode, err) } } func (a handler) sendHTTPError(w http.ResponseWriter, statusCode int, err error) { http.Error(w, http.StatusText(statusCode), statusCode) } func addEntry(ctx context.Context, i *Instance, w http.ResponseWriter, r *http.Request) (int, error) { glog.V(3).Info("handling add-entry request") leaf, appendix, err := i.LogParameters.newAddEntryRequest(r) if err != nil { return http.StatusBadRequest, err } treq := trillian.QueueLeafRequest{ LogId: i.LogParameters.TreeId, Leaf: &trillian.LogLeaf{ LeafValue: leaf, ExtraData: appendix, }, } trsp, err := i.Client.QueueLeaf(ctx, &treq) if err != nil { return http.StatusInternalServerError, fmt.Errorf("backend QueueLeaf request failed: %v", err) } if status, err := checkQueueLeaf(trsp); err != nil { return status, err } sdi, err := GenV1SDI(i.LogParameters, trsp.QueuedLeaf.Leaf.LeafValue) if err != nil { return http.StatusInternalServerError, fmt.Errorf("failed creating signed debug info: %v", err) } rsp, err := sdi.MarshalB64() if err != nil { return http.StatusInternalServerError, err } if err := writeJsonResponse(rsp, w); err != nil { return http.StatusInternalServerError, err } return http.StatusOK, nil } // getEntries provides a list of entries from the Trillian backend func getEntries(ctx context.Context, i *Instance, w http.ResponseWriter, r *http.Request) (int, error) { glog.V(3).Info("handling get-entries request") req, err := i.LogParameters.newGetEntriesRequest(r) if err != nil { return http.StatusBadRequest, err } treq := trillian.GetLeavesByRangeRequest{ LogId: i.LogParameters.TreeId, StartIndex: req.Start, Count: req.End - req.Start + 1, } trsp, err := i.Client.GetLeavesByRange(ctx, &treq) if err != nil { return http.StatusInternalServerError, fmt.Errorf("backend GetLeavesByRange request failed: %v", err) } if status, err := checkGetLeavesByRange(trsp, req); err != nil { return status, err } rsp, err := i.LogParameters.newGetEntriesResponse(trsp.Leaves) if err != nil { return http.StatusInternalServerError, fmt.Errorf("failed creating GetEntriesResponse: %v", err) } if err := writeJsonResponse(rsp, w); err != nil { return http.StatusInternalServerError, err } return http.StatusOK, nil } // getAnchors provides a list of configured trust anchors func getAnchors(_ context.Context, i *Instance, w http.ResponseWriter, _ *http.Request) (int, error) { glog.V(3).Info("handling get-anchors request") data := i.LogParameters.newGetAnchorsResponse() if err := writeJsonResponse(data, w); err != nil { return http.StatusInternalServerError, err } return http.StatusOK, nil } // getProofByHash provides an inclusion proof based on a given leaf hash func getProofByHash(ctx context.Context, i *Instance, w http.ResponseWriter, r *http.Request) (int, error) { glog.V(3).Info("handling get-proof-by-hash request") req, err := i.LogParameters.newGetProofByHashRequest(r) if err != nil { return http.StatusBadRequest, err } treq := trillian.GetInclusionProofByHashRequest{ LogId: i.LogParameters.TreeId, LeafHash: req.Hash, TreeSize: req.TreeSize, OrderBySequence: true, } trsp, err := i.Client.GetInclusionProofByHash(ctx, &treq) if err != nil { return http.StatusInternalServerError, fmt.Errorf("failed fetching inclusion proof from Trillian backend: %v", err) } if status, err := checkGetInclusionProofByHash(trsp, i.LogParameters); err != nil { return status, err } rsp, err := NewInclusionProofV1(i.LogParameters.LogId, uint64(req.TreeSize), trsp.Proof[0]).MarshalB64() if err != nil { return http.StatusInternalServerError, err } if err := writeJsonResponse(rsp, w); err != nil { return http.StatusInternalServerError, err } return http.StatusOK, nil } // getConsistencyProof provides a consistency proof between two STHs func getConsistencyProof(ctx context.Context, i *Instance, w http.ResponseWriter, r *http.Request) (int, error) { glog.V(3).Info("handling get-consistency-proof request") req, err := i.LogParameters.newGetConsistencyProofRequest(r) if err != nil { return http.StatusBadRequest, err } treq := trillian.GetConsistencyProofRequest{ LogId: i.LogParameters.TreeId, FirstTreeSize: int64(req.First), SecondTreeSize: int64(req.Second), } trsp, err := i.Client.GetConsistencyProof(ctx, &treq) if err != nil { return http.StatusInternalServerError, fmt.Errorf("failed fetching consistency proof from Trillian backend: %v", err) } if status, err := checkGetConsistencyProofResponse(trsp, i.LogParameters); err != nil { return status, err } rsp, err := NewConsistencyProofV1(i.LogParameters.LogId, req.First, req.Second, trsp.Proof).MarshalB64() if err != nil { return http.StatusInternalServerError, err } if err := writeJsonResponse(rsp, w); err != nil { return http.StatusInternalServerError, err } return http.StatusOK, nil } // getSth provides the most recent STH func getSth(ctx context.Context, i *Instance, w http.ResponseWriter, _ *http.Request) (int, error) { glog.V(3).Info("handling get-sth request") treq := trillian.GetLatestSignedLogRootRequest{ LogId: i.LogParameters.TreeId, } trsp, err := i.Client.GetLatestSignedLogRoot(ctx, &treq) if err != nil { return http.StatusInternalServerError, fmt.Errorf("failed fetching signed tree head from Trillian backend: %v", err) } if status, err := checkTrillianGetLatestSignedLogRoot(trsp, i.LogParameters); err != nil { return status, err } th, err := NewTreeHeadV1(i.LogParameters, trsp.SignedLogRoot) if err != nil { return http.StatusInternalServerError, fmt.Errorf("failed creating tree head: %v", err) } sth, err := GenV1STH(i.LogParameters, th) if err != nil { return http.StatusInternalServerError, fmt.Errorf("failed creating signed tree head: %v", err) } rsp, err := sth.MarshalB64() if err != nil { return http.StatusInternalServerError, err } if err := writeJsonResponse(rsp, w); err != nil { return http.StatusInternalServerError, err } return http.StatusOK, nil }