1 files changed, 3 insertions, 145 deletions

diff --git a/pkg/state/state_manager.go b/pkg/state/state_manager.go
index 84431be..5aa7609 100644
--- a/pkg/state/state_manager.go
+++ b/pkg/state/state_manager.go
@@ -2,157 +2,15 @@ package state
 
 import (
 	"context"
-	"crypto"
-	"crypto/ed25519"
-	"fmt"
-	"reflect"
-	"sync"
-	"time"
 
-	"github.com/golang/glog"
-	"github.com/google/certificate-transparency-go/schedule"
-	"git.sigsum.org/sigsum-log-go/pkg/trillian"
-	"git.sigsum.org/sigsum-log-go/pkg/types"
+	"git.sigsum.org/sigsum-lib-go/pkg/types"
 )
 
-// StateManager coordinates access to the log's tree heads and (co)signatures
+// StateManager coordinates access to a log's tree heads and (co)signatures
 type StateManager interface {
 	Latest(context.Context) (*types.SignedTreeHead, error)
 	ToSign(context.Context) (*types.SignedTreeHead, error)
 	Cosigned(context.Context) (*types.CosignedTreeHead, error)
-	AddCosignature(context.Context, *[types.VerificationKeySize]byte, *[types.SignatureSize]byte) error
+	AddCosignature(context.Context, *types.PublicKey, *types.Signature) error
 	Run(context.Context)
 }
-
-// StateManagerSingle implements the StateManager interface.  It is assumed that
-// the log server is running on a single-instance machine.  So, no coordination.
-type StateManagerSingle struct {
-	client   trillian.Client
-	signer   crypto.Signer
-	interval time.Duration
-	deadline time.Duration
-	sync.RWMutex
-
-	// cosigned is the current cosigned tree head that is being served
-	cosigned types.CosignedTreeHead
-
-	// tosign is the current tree head that is being cosigned by witnesses
-	tosign types.SignedTreeHead
-
-	// cosignature keeps track of all cosignatures for the tosign tree head
-	cosignature map[[types.HashSize]byte]*types.SigIdent
-}
-
-func NewStateManagerSingle(client trillian.Client, signer crypto.Signer, interval, deadline time.Duration) (*StateManagerSingle, error) {
-	sm := &StateManagerSingle{
-		client:   client,
-		signer:   signer,
-		interval: interval,
-		deadline: deadline,
-	}
-
-	ctx, _ := context.WithTimeout(context.Background(), sm.deadline)
-	sth, err := sm.Latest(ctx)
-	if err != nil {
-		return nil, fmt.Errorf("Latest: %v", err)
-	}
-
-	sm.cosigned = types.CosignedTreeHead{
-		SignedTreeHead: *sth,
-		SigIdent:       []*types.SigIdent{},
-	}
-	sm.tosign = *sth
-	sm.cosignature = map[[types.HashSize]byte]*types.SigIdent{}
-	return sm, nil
-}
-
-func (sm *StateManagerSingle) Run(ctx context.Context) {
-	schedule.Every(ctx, sm.interval, func(ctx context.Context) {
-		ictx, _ := context.WithTimeout(ctx, sm.deadline)
-		nextSTH, err := sm.Latest(ictx)
-		if err != nil {
-			glog.Warningf("rotate failed: Latest: %v", err)
-			return
-		}
-
-		sm.Lock()
-		defer sm.Unlock()
-		sm.rotate(nextSTH)
-	})
-}
-
-func (sm *StateManagerSingle) Latest(ctx context.Context) (*types.SignedTreeHead, error) {
-	th, err := sm.client.GetTreeHead(ctx)
-	if err != nil {
-		return nil, fmt.Errorf("LatestTreeHead: %v", err)
-	}
-	th.KeyHash = types.Hash(sm.signer.Public().(ed25519.PublicKey)[:])
-	sth, err := th.Sign(sm.signer)
-	if err != nil {
-		return nil, fmt.Errorf("sign: %v", err)
-	}
-	return sth, nil
-}
-
-func (sm *StateManagerSingle) ToSign(_ context.Context) (*types.SignedTreeHead, error) {
-	sm.RLock()
-	defer sm.RUnlock()
-	return &sm.tosign, nil
-}
-
-func (sm *StateManagerSingle) Cosigned(_ context.Context) (*types.CosignedTreeHead, error) {
-	sm.RLock()
-	defer sm.RUnlock()
-	if len(sm.cosigned.SigIdent) == 0 {
-		return nil, fmt.Errorf("no witness cosignatures available")
-	}
-	return &sm.cosigned, nil
-}
-
-func (sm *StateManagerSingle) AddCosignature(_ context.Context, vk *[types.VerificationKeySize]byte, sig *[types.SignatureSize]byte) error {
-	sm.Lock()
-	defer sm.Unlock()
-
-	if err := sm.tosign.TreeHead.Verify(vk, sig); err != nil {
-		return fmt.Errorf("Verify: %v", err)
-	}
-	witness := types.Hash(vk[:])
-	if _, ok := sm.cosignature[*witness]; ok {
-		return fmt.Errorf("signature-signer pair is a duplicate")
-	}
-	sm.cosignature[*witness] = &types.SigIdent{
-		Signature: sig,
-		KeyHash:   witness,
-	}
-
-	glog.V(3).Infof("accepted new cosignature from witness: %x", *witness)
-	return nil
-}
-
-// rotate rotates the log's cosigned and stable STH.  The caller must aquire the
-// source's read-write lock if there are concurrent reads and/or writes.
-func (sm *StateManagerSingle) rotate(next *types.SignedTreeHead) {
-	if reflect.DeepEqual(sm.cosigned.SignedTreeHead, sm.tosign) {
-		// cosigned and tosign are the same.  So, we need to merge all
-		// cosignatures that we already had with the new collected ones.
-		for _, sigident := range sm.cosigned.SigIdent {
-			if _, ok := sm.cosignature[*sigident.KeyHash]; !ok {
-				sm.cosignature[*sigident.KeyHash] = sigident
-			}
-		}
-		glog.V(3).Infof("cosigned tree head repeated, merged signatures")
-	}
-	var cosignatures []*types.SigIdent
-	for _, sigident := range sm.cosignature {
-		cosignatures = append(cosignatures, sigident)
-	}
-
-	// Update cosigned tree head
-	sm.cosigned.SignedTreeHead = sm.tosign
-	sm.cosigned.SigIdent = cosignatures
-
-	// Update to-sign tree head
-	sm.tosign = *next
-	sm.cosignature = map[[types.HashSize]byte]*types.SigIdent{} // TODO: on repeat we might want to not zero this
-	glog.V(3).Infof("rotated tree heads")
-}