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authorRasmus Dahlberg <rasmus.dahlberg@kau.se>2021-06-07 00:19:40 +0200
committerRasmus Dahlberg <rasmus.dahlberg@kau.se>2021-06-07 00:19:40 +0200
commit932d29fd08c8ff401e471b4f764537493ccbd483 (patch)
treee840a4c62db92e84201fe9ceaa0594d99176792c /sth.go
parentbdf7a53d61cf044e526cc9123ca296615f838288 (diff)
parent345fe658fa8a4306caa74f72a618e499343675c2 (diff)
Merge branch 'design' into main
Diffstat (limited to 'sth.go')
-rw-r--r--sth.go155
1 files changed, 0 insertions, 155 deletions
diff --git a/sth.go b/sth.go
deleted file mode 100644
index ee4dd2f..0000000
--- a/sth.go
+++ /dev/null
@@ -1,155 +0,0 @@
-package stfe
-
-import (
- "context"
- "fmt"
- "reflect"
- "sync"
-
- "github.com/golang/glog"
- "github.com/google/certificate-transparency-go/schedule"
- "github.com/google/trillian"
- ttypes "github.com/google/trillian/types"
- "github.com/system-transparency/stfe/types"
-)
-
-// SthSource provides access to the log's STHs.
-type SthSource interface {
- // Latest returns the most reccent signed_tree_head_v*.
- Latest(context.Context) (*types.StItem, error)
- // Stable returns the most recent signed_tree_head_v* that is stable for
- // some period of time, e.g., 10 minutes.
- Stable(context.Context) (*types.StItem, error)
- // Cosigned returns the most recent cosigned_tree_head_v*.
- Cosigned(context.Context) (*types.StItem, error)
- // AddCosignature attempts to add a cosignature to the stable STH. The
- // passed cosigned_tree_head_v* must have a single verified cosignature.
- AddCosignature(context.Context, *types.StItem) error
- // Run keeps the STH source updated until cancelled
- Run(context.Context)
-}
-
-// ActiveSthSource implements the SthSource interface for an STFE instance that
-// accepts new logging requests, i.e., the log is running in read+write mode.
-type ActiveSthSource struct {
- client trillian.TrillianLogClient
- logParameters *LogParameters
- currCosth *types.StItem // current cosigned_tree_head_v1 (already finalized)
- nextCosth *types.StItem // next cosigned_tree_head_v1 (under preparation)
- cosignatureFrom map[[types.NamespaceFingerprintSize]byte]bool // track who we got cosignatures from in nextCosth
- mutex sync.RWMutex
-}
-
-// NewActiveSthSource returns an initialized ActiveSthSource
-func NewActiveSthSource(cli trillian.TrillianLogClient, lp *LogParameters) (*ActiveSthSource, error) {
- s := ActiveSthSource{
- client: cli,
- logParameters: lp,
- }
-
- ctx, _ := context.WithTimeout(context.Background(), lp.Deadline)
- sth, err := s.Latest(ctx)
- if err != nil {
- return nil, fmt.Errorf("Latest: %v", err)
- }
-
- // TODO: load persisted cosigned STH?
- s.currCosth = types.NewCosignedTreeHeadV1(sth.SignedTreeHeadV1, nil)
- s.nextCosth = types.NewCosignedTreeHeadV1(sth.SignedTreeHeadV1, nil)
- s.cosignatureFrom = make(map[[types.NamespaceFingerprintSize]byte]bool)
- return &s, nil
-}
-
-func (s *ActiveSthSource) Run(ctx context.Context) {
- schedule.Every(ctx, s.logParameters.Interval, func(ctx context.Context) {
- // get the next stable sth
- ictx, _ := context.WithTimeout(ctx, s.logParameters.Deadline)
- sth, err := s.Latest(ictx)
- if err != nil {
- glog.Warningf("cannot rotate without new sth: Latest: %v", err)
- return
- }
- // rotate
- s.mutex.Lock()
- defer s.mutex.Unlock()
- if err := s.rotate(sth); err != nil {
- glog.Warningf("rotate failed: %v", err)
- }
- // TODO: persist cosigned STH?
- })
-}
-
-func (s *ActiveSthSource) Latest(ctx context.Context) (*types.StItem, error) {
- trsp, err := s.client.GetLatestSignedLogRoot(ctx, &trillian.GetLatestSignedLogRootRequest{
- LogId: s.logParameters.TreeId,
- })
- var lr ttypes.LogRootV1
- if errInner := checkGetLatestSignedLogRoot(s.logParameters, trsp, err, &lr); errInner != nil {
- return nil, fmt.Errorf("invalid signed log root response: %v", errInner)
- }
- return s.logParameters.SignTreeHeadV1(NewTreeHeadV1FromLogRoot(&lr))
-}
-
-func (s *ActiveSthSource) Stable(_ context.Context) (*types.StItem, error) {
- s.mutex.RLock()
- defer s.mutex.RUnlock()
- if s.nextCosth == nil {
- return nil, fmt.Errorf("no stable sth available")
- }
- return types.NewSignedTreeHeadV1(&s.nextCosth.CosignedTreeHeadV1.SignedTreeHead.TreeHead, &s.nextCosth.CosignedTreeHeadV1.SignedTreeHead.Signature), nil
-}
-
-func (s *ActiveSthSource) Cosigned(_ context.Context) (*types.StItem, error) {
- s.mutex.RLock()
- defer s.mutex.RUnlock()
- if s.currCosth == nil {
- return nil, fmt.Errorf("no cosigned sth available")
- }
- return s.currCosth, nil
-}
-
-func (s *ActiveSthSource) AddCosignature(_ context.Context, costh *types.StItem) error {
- s.mutex.Lock()
- defer s.mutex.Unlock()
- if !reflect.DeepEqual(s.nextCosth.CosignedTreeHeadV1.SignedTreeHead, costh.CosignedTreeHeadV1.SignedTreeHead) {
- return fmt.Errorf("cosignature covers a different tree head")
- }
- witness, err := costh.CosignedTreeHeadV1.Cosignatures[0].Namespace.Fingerprint()
- if err != nil {
- return fmt.Errorf("namespace without fingerprint: %v", err)
- }
- if _, ok := s.cosignatureFrom[*witness]; ok {
- return nil // duplicate
- }
- s.cosignatureFrom[*witness] = true
- s.nextCosth.CosignedTreeHeadV1.Cosignatures = append(s.nextCosth.CosignedTreeHeadV1.Cosignatures, costh.CosignedTreeHeadV1.Cosignatures[0])
- 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 (s *ActiveSthSource) rotate(fixedSth *types.StItem) error {
- // rotate stable -> cosigned
- if reflect.DeepEqual(&s.currCosth.CosignedTreeHeadV1.SignedTreeHead, &s.nextCosth.CosignedTreeHeadV1.SignedTreeHead) {
- for _, sigv1 := range s.currCosth.CosignedTreeHeadV1.Cosignatures {
- witness, err := sigv1.Namespace.Fingerprint()
- if err != nil {
- return fmt.Errorf("namespace without fingerprint: %v", err)
- }
- if _, ok := s.cosignatureFrom[*witness]; !ok {
- s.cosignatureFrom[*witness] = true
- s.nextCosth.CosignedTreeHeadV1.Cosignatures = append(s.nextCosth.CosignedTreeHeadV1.Cosignatures, sigv1)
- }
- }
- }
- s.currCosth.CosignedTreeHeadV1.SignedTreeHead = s.nextCosth.CosignedTreeHeadV1.SignedTreeHead
- s.currCosth.CosignedTreeHeadV1.Cosignatures = make([]types.SignatureV1, len(s.nextCosth.CosignedTreeHeadV1.Cosignatures))
- copy(s.currCosth.CosignedTreeHeadV1.Cosignatures, s.nextCosth.CosignedTreeHeadV1.Cosignatures)
-
- // rotate new stable -> stable
- if !reflect.DeepEqual(&s.nextCosth.CosignedTreeHeadV1.SignedTreeHead, fixedSth.SignedTreeHeadV1) {
- s.nextCosth = types.NewCosignedTreeHeadV1(fixedSth.SignedTreeHeadV1, nil)
- s.cosignatureFrom = make(map[[types.NamespaceFingerprintSize]byte]bool)
- }
- return nil
-}