started to clean-up instance

Things like opening files is better place in the server package.  Any
code that is difficult to test should also not be in the STFE package.

1 files changed, 49 insertions, 92 deletions

diff --git a/instance.go b/instance.go
index 2c108aa..b0a2d9e 100644
--- a/instance.go
+++ b/instance.go
@@ -9,31 +9,12 @@ import (
 	"crypto/sha256"
 	"crypto/x509"
 	"encoding/base64"
-	"io/ioutil"
 	"net/http"
 
-	"github.com/golang/glog"
 	"github.com/google/trillian"
 	"github.com/system-transparency/stfe/x509util"
 )
 
-type Endpoint string
-
-const (
-	EndpointAddEntry            = Endpoint("add-entry")
-	EndpointGetEntries          = Endpoint("get-entries")
-	EndpointGetAnchors          = Endpoint("get-anchors")
-	EndpointGetProofByHash      = Endpoint("get-proof-by-hash")
-	EndpointGetConsistencyProof = Endpoint("get-consistency-proof")
-	EndpointGetSth              = Endpoint("get-sth")
-)
-
-// Path joins a number of components to form a full endpoint path, e.g., base
-// ("example.com"), prefix ("st/v1"), and the endpoint itself ("get-sth").
-func (e Endpoint) Path(components ...string) string {
-	return strings.Join(append(components, string(e)), "/")
-}
-
 // Instance is an instance of a particular log front-end
 type Instance struct {
 	LogParameters *LogParameters
@@ -55,6 +36,18 @@ type LogParameters struct {
 	HashType   crypto.Hash // hash function used by Trillian
 }
 
+// Endpoint is a named HTTP API endpoint
+type Endpoint string
+
+const (
+	EndpointAddEntry            = Endpoint("add-entry")
+	EndpointGetEntries          = Endpoint("get-entries")
+	EndpointGetAnchors          = Endpoint("get-anchors")
+	EndpointGetProofByHash      = Endpoint("get-proof-by-hash")
+	EndpointGetConsistencyProof = Endpoint("get-consistency-proof")
+	EndpointGetSth              = Endpoint("get-sth")
+)
+
 func (i Instance) String() string {
 	return fmt.Sprintf("%s Deadline(%v)\n", i.LogParameters, i.Deadline)
 }
@@ -63,103 +56,67 @@ func (p LogParameters) String() string {
 	return fmt.Sprintf("LogId(%s) TreeId(%d) Prefix(%s) NumAnchors(%d)", base64.StdEncoding.EncodeToString(p.LogId), p.TreeId, p.Prefix, len(p.AnchorList))
 }
 
-func (i *LogParameters) id() string {
-	return base64.StdEncoding.EncodeToString(i.LogId)
+func (e Endpoint) String() string {
+	return string(e)
 }
 
-// NewInstance returns a new STFE Instance
-func NewInstance(lp *LogParameters, client trillian.TrillianLogClient, deadline time.Duration, mux *http.ServeMux) (*Instance, error) {
-	i := &Instance{
+// NewInstance creates a new STFE instance
+func NewInstance(lp *LogParameters, client trillian.TrillianLogClient, deadline time.Duration, mux *http.ServeMux) *Instance {
+	return &Instance{
 		LogParameters: lp,
 		Client:        client,
 		Deadline:      deadline,
 	}
-	i.registerHandlers(mux)
-	return i, nil
 }
 
-// NewLogParameters initializes log parameters, assuming ed25519 signatures.
-func NewLogParameters(treeId int64, prefix string, anchorPath, keyPath string, maxRange, maxChain int64) (*LogParameters, error) {
-	anchorList, anchorPool, err := loadTrustAnchors(anchorPath)
+// NewLogParameters creates new log parameters.  Note that the signer is
+// assumed to be an ed25519 signing key.  Could be fixed at some point.
+func NewLogParameters(treeId int64, prefix string, anchors []*x509.Certificate, signer crypto.Signer, maxRange, maxChain int64) (*LogParameters, error) {
+	pub, err := x509.MarshalPKIXPublicKey(signer.Public())
 	if err != nil {
-		return nil, err
-	}
-
-	pem, err := ioutil.ReadFile(keyPath)
-	if err != nil {
-		return nil, fmt.Errorf("failed reading %s: %v", keyPath, err)
+		return nil, fmt.Errorf("failed DER encoding SubjectPublicKeyInfo: %v", err)
 	}
-	key, err := x509util.NewEd25519PrivateKey(pem)
-	if err != nil {
-		return nil, err
+	if maxRange < 1 {
+		return nil, fmt.Errorf("invalid max range: must be at least 1")
 	}
-
-	pub, err := x509.MarshalPKIXPublicKey(key.Public())
-	if err != nil {
-		return nil, fmt.Errorf("failed DER encoding SubjectPublicKeyInfo: %v", err)
+	if maxChain < 1 {
+		return nil, fmt.Errorf("invalid max chain: must be at least 1")
 	}
 	hasher := sha256.New()
 	hasher.Write(pub)
-	logId := hasher.Sum(nil)
-
 	return &LogParameters{
-		LogId:      logId,
+		LogId:      hasher.Sum(nil),
 		TreeId:     treeId,
 		Prefix:     prefix,
 		MaxRange:   maxRange,
 		MaxChain:   maxChain,
-		AnchorPool: anchorPool,
-		AnchorList: anchorList,
+		AnchorPool: x509util.NewCertPool(anchors),
+		AnchorList: anchors,
 		KeyUsage:   []x509.ExtKeyUsage{}, // placeholder, must be tested if used
-		Signer:     key,
-		HashType:   crypto.SHA256,
+		Signer:     signer,
+		HashType:   crypto.SHA256, // STFE assumes RFC 6962 hashing
 	}, nil
 }
 
-func (i *Instance) registerHandlers(mux *http.ServeMux) {
-	for _, endpoint := range []struct {
-		path    string
-		handler handler
-	}{
-		{
-			EndpointAddEntry.Path("", i.LogParameters.Prefix),
-			handler{instance: i, handler: addEntry, endpoint: EndpointAddEntry, method: http.MethodPost},
-		},
-		{
-			EndpointGetEntries.Path("", i.LogParameters.Prefix),
-			handler{instance: i, handler: getEntries, endpoint: EndpointGetEntries, method: http.MethodGet},
-		},
-		{
-			EndpointGetAnchors.Path("", i.LogParameters.Prefix),
-			handler{instance: i, handler: getAnchors, endpoint: EndpointGetAnchors, method: http.MethodGet},
-		},
-		{
-			EndpointGetProofByHash.Path("", i.LogParameters.Prefix),
-			handler{instance: i, handler: getProofByHash, endpoint: EndpointGetProofByHash, method: http.MethodGet},
-		},
-		{
-			EndpointGetConsistencyProof.Path("", i.LogParameters.Prefix),
-			handler{instance: i, handler: getConsistencyProof, endpoint: EndpointGetConsistencyProof, method: http.MethodGet},
-		},
-		{
-			EndpointGetSth.Path("", i.LogParameters.Prefix),
-			handler{instance: i, handler: getSth, endpoint: EndpointGetSth, method: http.MethodGet},
-		},
-	} {
-		glog.Infof("adding handler for %v", endpoint.path)
-		mux.Handle(endpoint.path, endpoint.handler)
-	}
+// Path joins a number of components to form a full endpoint path, e.g., base
+// ("example.com"), prefix ("st/v1"), and the endpoint itself ("get-sth").
+func (e Endpoint) Path(components ...string) string {
+	return strings.Join(append(components, string(e)), "/")
 }
 
-// loadTrustAnchors loads a list of PEM-encoded certificates from file
-func loadTrustAnchors(path string) ([]*x509.Certificate, *x509.CertPool, error) {
-	pem, err := ioutil.ReadFile(path)
-	if err != nil {
-		return nil, nil, fmt.Errorf("failed reading trust anchors: %v", err)
-	}
-	anchorList, err := x509util.NewCertificateList(pem)
-	if err != nil || len(anchorList) == 0 {
-		return nil, nil, fmt.Errorf("failed parsing trust anchors: %v", err)
+// TODO: id() docdoc
+func (i *LogParameters) id() string {
+	return base64.StdEncoding.EncodeToString(i.LogId)
+}
+
+// Handlers returns a list of STFE handlers
+func (i *Instance) Handlers() []Handler {
+	return []Handler{
+		Handler{instance: i, handler: addEntry, endpoint: EndpointAddEntry, method: http.MethodPost},
+		Handler{instance: i, handler: getEntries, endpoint: EndpointGetEntries, method: http.MethodGet},
+		Handler{instance: i, handler: getAnchors, endpoint: EndpointGetAnchors, method: http.MethodGet},
+		Handler{instance: i, handler: getProofByHash, endpoint: EndpointGetProofByHash, method: http.MethodGet},
+		Handler{instance: i, handler: getConsistencyProof, endpoint: EndpointGetConsistencyProof, method: http.MethodGet},
+		Handler{instance: i, handler: getSth, endpoint: EndpointGetSth, method: http.MethodGet},
 	}
-	return anchorList, x509util.NewCertPool(anchorList), nil
 }