Update loginfo API endpoint to return information about inactive shards (#738)

* Update loginfo to return info about inactive shards

This also updates `rekor-cli` to verify inactive shards if they exist. It also updates the sharding integration test to run loginfo and store state based on TreeID if available.

Signed-off-by: Priya Wadhwa <priya@chainguard.dev>

* Fix typo

Signed-off-by: Priya Wadhwa <priya@chainguard.dev>

* specify resp code in error

Signed-off-by: Priya Wadhwa <priya@chainguard.dev>

Author: priyawadhwa

cmd/rekor-cli/app/log_info.go

@@ -21,14 +21,15 @@ import (
 	"crypto/x509"
 	"encoding/hex"
 	"encoding/pem"
-	"errors"
 	"fmt"
 	"time"
 
 	"github.com/go-openapi/swag"
 	"github.com/google/trillian/merkle/logverifier"
 	"github.com/google/trillian/merkle/rfc6962"
+	"github.com/pkg/errors"
 	rclient "github.com/sigstore/rekor/pkg/generated/client"
+	"github.com/sigstore/rekor/pkg/generated/models"
 	"github.com/spf13/cobra"
 	"github.com/spf13/viper"
 
@@ -81,13 +82,20 @@ var logInfoCmd = &cobra.Command{
 
 		logInfo := result.GetPayload()
 
+		// Verify inactive shards
+		if err := verifyInactiveTrees(rekorClient, serverURL, logInfo.InactiveShards); err != nil {
+			return nil, err
+		}
+
+		// Verify the active tree
 		sth := util.SignedCheckpoint{}
 		signedTreeHead := swag.StringValue(logInfo.SignedTreeHead)
 		if err := sth.UnmarshalText([]byte(signedTreeHead)); err != nil {
 			return nil, err
 		}
+		treeID := swag.StringValue(logInfo.TreeID)
 
-		if err := verifyTree(rekorClient, signedTreeHead, serverURL); err != nil {
+		if err := verifyTree(rekorClient, signedTreeHead, serverURL, treeID); err != nil {
 			return nil, err
 		}
 
@@ -101,8 +109,27 @@ var logInfoCmd = &cobra.Command{
 	}),
 }
 
-func verifyTree(rekorClient *rclient.Rekor, signedTreeHead, serverURL string) error {
+func verifyInactiveTrees(rekorClient *rclient.Rekor, serverURL string, inactiveShards []*models.InactiveShardLogInfo) error {
+	if inactiveShards == nil {
+		return nil
+	}
+	log.CliLogger.Infof("Validating inactive shards...")
+	for _, shard := range inactiveShards {
+		signedTreeHead := swag.StringValue(shard.SignedTreeHead)
+		treeID := swag.StringValue(shard.TreeID)
+		if err := verifyTree(rekorClient, signedTreeHead, serverURL, treeID); err != nil {
+			return errors.Wrapf(err, "verifying inactive shard with ID %s", treeID)
+		}
+	}
+	log.CliLogger.Infof("Successfully validated inactive shards")
+	return nil
+}
+
+func verifyTree(rekorClient *rclient.Rekor, signedTreeHead, serverURL, treeID string) error {
 	oldState := state.Load(serverURL)
+	if treeID != "" {
+		oldState = state.Load(treeID)
+	}
 	sth := util.SignedCheckpoint{}
 	if err := sth.UnmarshalText([]byte(signedTreeHead)); err != nil {
 		return err
@@ -115,19 +142,24 @@ func verifyTree(rekorClient *rclient.Rekor, signedTreeHead, serverURL string) er
 		return errors.New("signature on tree head did not verify")
 	}
 
-	if err := proveConsistency(rekorClient, oldState, sth); err != nil {
+	if err := proveConsistency(rekorClient, oldState, sth, treeID); err != nil {
 		return err
 	}
 
 	if viper.GetBool("store_tree_state") {
+		if treeID != "" {
+			if err := state.Dump(treeID, &sth); err != nil {
+				log.CliLogger.Infof("Unable to store previous state: %v", err)
+			}
+		}
 		if err := state.Dump(serverURL, &sth); err != nil {
 			log.CliLogger.Infof("Unable to store previous state: %v", err)
 		}
 	}
 	return nil
 }
 
-func proveConsistency(rekorClient *rclient.Rekor, oldState *util.SignedCheckpoint, sth util.SignedCheckpoint) error {
+func proveConsistency(rekorClient *rclient.Rekor, oldState *util.SignedCheckpoint, sth util.SignedCheckpoint, treeID string) error {
 	if oldState == nil {
 		log.CliLogger.Infof("No previous log state stored, unable to prove consistency")
 		return nil
@@ -140,6 +172,7 @@ func proveConsistency(rekorClient *rclient.Rekor, oldState *util.SignedCheckpoin
 		firstSize := int64(persistedSize)
 		params.FirstSize = &firstSize
 		params.LastSize = int64(sth.Size)
+		params.TreeID = &treeID
 		proof, err := rekorClient.Tlog.GetLogProof(params)
 		if err != nil {
 			return err

cmd/rekor-cli/app/state/state.go

@@ -27,7 +27,7 @@ import (
 
 type persistedState map[string]*util.SignedCheckpoint
 
-func Dump(url string, sth *util.SignedCheckpoint) error {
+func Dump(key string, sth *util.SignedCheckpoint) error {
 	rekorDir, err := getRekorDir()
 	if err != nil {
 		return err
@@ -38,7 +38,7 @@ func Dump(url string, sth *util.SignedCheckpoint) error {
 	if state == nil {
 		state = make(persistedState)
 	}
-	state[url] = sth
+	state[key] = sth
 
 	b, err := json.Marshal(&state)
 	if err != nil {
@@ -67,9 +67,9 @@ func loadStateFile() persistedState {
 	return result
 }
 
-func Load(url string) *util.SignedCheckpoint {
+func Load(key string) *util.SignedCheckpoint {
 	if state := loadStateFile(); state != nil {
-		return state[url]
+		return state[key]
 	}
 	return nil
 }

openapi.yaml

@@ -572,6 +572,35 @@ definitions:
           minItems: 1
 
   LogInfo:
+    type: object
+    properties:
+      rootHash:
+        type: string
+        description: The current hash value stored at the root of the merkle tree
+        pattern: '^[0-9a-fA-F]{64}$'
+      treeSize:
+        type: integer
+        description: The current number of nodes in the merkle tree
+        minimum: 1
+      signedTreeHead:
+        type: string
+        format: signedCheckpoint
+        description: The current signed tree head
+      treeID:
+        type: string
+        description: The current treeID
+        pattern: '^[0-9]+$'
+      inactiveShards:
+        type: array
+        items:
+          $ref: '#/definitions/InactiveShardLogInfo'
+
+    required:
+      - rootHash
+      - treeSize
+      - signedTreeHead
+      - treeID
+  InactiveShardLogInfo:
     type: object
     properties:
       rootHash:

pkg/api/error.go

@@ -49,6 +49,7 @@ const (
 	failedToGenerateTimestampResponse = "Error generating timestamp response"
 	sthGenerateError                  = "Error generating signed tree head"
 	unsupportedPKIFormat              = "The PKI format requested is not supported by this server"
+	unexpectedInactiveShardError      = "Unexpected error communicating with inactive shard"
 )
 
 func errorMsg(message string, code int) *models.Error {

pkg/api/tlog.go

@@ -16,6 +16,7 @@
 package api
 
 import (
+	"context"
 	"encoding/hex"
 	"fmt"
 	"net/http"
@@ -39,6 +40,20 @@ import (
 func GetLogInfoHandler(params tlog.GetLogInfoParams) middleware.Responder {
 	tc := NewTrillianClient(params.HTTPRequest.Context())
 
+	// for each inactive shard, get the loginfo
+	var inactiveShards []*models.InactiveShardLogInfo
+	for _, shard := range tc.ranges.GetRanges() {
+		if shard.TreeID == tc.ranges.ActiveTreeID() {
+			break
+		}
+		// Get details for this inactive shard
+		is, err := inactiveShardLogInfo(params.HTTPRequest.Context(), shard.TreeID)
+		if err != nil {
+			return handleRekorAPIError(params, http.StatusInternalServerError, fmt.Errorf("inactive shard error: %w", err), unexpectedInactiveShardError)
+		}
+		inactiveShards = append(inactiveShards, is)
+	}
+
 	resp := tc.getLatest(0)
 	if resp.status != codes.OK {
 		return handleRekorAPIError(params, http.StatusInternalServerError, fmt.Errorf("grpc error: %w", resp.err), trillianCommunicationError)
@@ -80,6 +95,7 @@ func GetLogInfoHandler(params tlog.GetLogInfoParams) middleware.Responder {
 		TreeSize:       &treeSize,
 		SignedTreeHead: &scString,
 		TreeID:         stringPointer(fmt.Sprintf("%d", tc.logID)),
+		InactiveShards: inactiveShards,
 	}
 
 	return tlog.NewGetLogInfoOK().WithPayload(&logInfo)
@@ -136,3 +152,47 @@ func GetLogProofHandler(params tlog.GetLogProofParams) middleware.Responder {
 
 	return tlog.NewGetLogProofOK().WithPayload(&consistencyProof)
 }
+
+func inactiveShardLogInfo(ctx context.Context, tid int64) (*models.InactiveShardLogInfo, error) {
+	tc := NewTrillianClientFromTreeID(ctx, tid)
+	resp := tc.getLatest(0)
+	if resp.status != codes.OK {
+		return nil, fmt.Errorf("resp code is %d", resp.status)
+	}
+	result := resp.getLatestResult
+
+	root := &types.LogRootV1{}
+	if err := root.UnmarshalBinary(result.SignedLogRoot.LogRoot); err != nil {
+		return nil, err
+	}
+
+	hashString := hex.EncodeToString(root.RootHash)
+	treeSize := int64(root.TreeSize)
+
+	sth, err := util.CreateSignedCheckpoint(util.Checkpoint{
+		Origin: "Rekor",
+		Size:   root.TreeSize,
+		Hash:   root.RootHash,
+	})
+	if err != nil {
+		return nil, err
+	}
+	sth.SetTimestamp(uint64(time.Now().UnixNano()))
+
+	// sign the log root ourselves to get the log root signature
+	if _, err := sth.Sign(viper.GetString("rekor_server.hostname"), api.signer, options.WithContext(ctx)); err != nil {
+		return nil, err
+	}
+
+	scBytes, err := sth.SignedNote.MarshalText()
+	if err != nil {
+		return nil, err
+	}
+	m := models.InactiveShardLogInfo{
+		RootHash:       &hashString,
+		TreeSize:       &treeSize,
+		TreeID:         stringPointer(fmt.Sprintf("%d", tid)),
+		SignedTreeHead: stringPointer(string(scBytes)),
+	}
+	return &m, nil
+}

pkg/api/trillian_client.go

@@ -25,6 +25,7 @@ import (
 	"github.com/google/trillian/merkle/rfc6962"
 	"github.com/pkg/errors"
 	"github.com/sigstore/rekor/pkg/log"
+	"github.com/sigstore/rekor/pkg/sharding"
 
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/status"
@@ -37,13 +38,15 @@ import (
 
 type TrillianClient struct {
 	client  trillian.TrillianLogClient
+	ranges  sharding.LogRanges
 	logID   int64
 	context context.Context
 }
 
 func NewTrillianClient(ctx context.Context) TrillianClient {
 	return TrillianClient{
 		client:  api.logClient,
+		ranges:  api.logRanges,
 		logID:   api.logID,
 		context: ctx,
 	}