make signBytesHRS a method on LastSignedInfo

types/priv_validator.go

@@ -34,7 +34,8 @@ func voteToStep(vote *Vote) int8 {
 	}
 }
 
-// PrivValidator defines the functionality of a local Tendermint validator.
+// PrivValidator defines the functionality of a local Tendermint validator
+// that signs votes, proposals, and heartbeats, and never double signs.
 type PrivValidator interface {
 	Address() data.Bytes // redundant since .PubKey().Address()
 	PubKey() crypto.PubKey
@@ -61,77 +62,56 @@ type PrivValidatorFS struct {
 	filePath string
 }
 
-// LoadOrGenPrivValidatorFS loads a PrivValidatorFS from the given filePath
-// or else generates a new one and saves it to the filePath.
-func LoadOrGenPrivValidatorFS(filePath string) *PrivValidatorFS {
-	var PrivValidatorFS *PrivValidatorFS
-	if _, err := os.Stat(filePath); err == nil {
-		PrivValidatorFS = LoadPrivValidatorFS(filePath)
-	} else {
-		PrivValidatorFS = GenPrivValidatorFS(filePath)
-		PrivValidatorFS.Save()
-	}
-	return PrivValidatorFS
+// Address returns the address of the validator.
+// Implements PrivValidator.
+func (pv *PrivValidatorFS) Address() data.Bytes {
+	return pv.ID.Address
 }
 
-// LoadPrivValidatorFS loads a PrivValidatorFS from the filePath.
-func LoadPrivValidatorFS(filePath string) *PrivValidatorFS {
-	privValJSONBytes, err := ioutil.ReadFile(filePath)
-	if err != nil {
-		cmn.Exit(err.Error())
-	}
-	privVal := PrivValidatorFS{}
-	err = json.Unmarshal(privValJSONBytes, &privVal)
-	if err != nil {
-		cmn.Exit(cmn.Fmt("Error reading PrivValidator from %v: %v\n", filePath, err))
-	}
-
-	privVal.filePath = filePath
-	return &privVal
+// PubKey returns the public key of the validator.
+// Implements PrivValidator.
+func (pv *PrivValidatorFS) PubKey() crypto.PubKey {
+	return pv.ID.PubKey
 }
 
-// GenPrivValidatorFS generates a new validator with randomly generated private key
-// and sets the filePath, but does not call Save().
-func GenPrivValidatorFS(filePath string) *PrivValidatorFS {
-	privKey := crypto.GenPrivKeyEd25519().Wrap()
-	return &PrivValidatorFS{
-		ID: ValidatorID{privKey.PubKey().Address(), privKey.PubKey()},
-		Info: LastSignedInfo{
-			LastStep: stepNone,
-		},
-		Signer:   NewDefaultSigner(privKey),
-		filePath: filePath,
+// SignVote signs a canonical representation of the vote, along with the chainID.
+// Implements PrivValidator.
+func (privVal *PrivValidatorFS) SignVote(chainID string, vote *Vote) error {
+	privVal.mtx.Lock()
+	defer privVal.mtx.Unlock()
+	signature, err := privVal.Info.SignBytesHRS(privVal.Signer,
+		vote.Height, vote.Round, voteToStep(vote), SignBytes(chainID, vote))
+	if err != nil {
+		return errors.New(cmn.Fmt("Error signing vote: %v", err))
 	}
+	privVal.save()
+	vote.Signature = signature
+	return nil
 }
 
-// LoadPrivValidatorWithSigner loads a PrivValidatorFS with a custom
-// signer object. The PrivValidatorFS handles double signing prevention by persisting
-// data to the filePath, while the Signer handles the signing.
-// If the filePath does not exist, the PrivValidatorFS must be created manually and saved.
-func LoadPrivValidatorFSWithSigner(filePath string, signerFunc func(ValidatorID) Signer) *PrivValidatorFS {
-	privValJSONBytes, err := ioutil.ReadFile(filePath)
-	if err != nil {
-		cmn.Exit(err.Error())
-	}
-	privVal := PrivValidatorFS{}
-	err = json.Unmarshal(privValJSONBytes, &privVal)
+// SignProposal signs a canonical representation of the proposal, along with the chainID.
+// Implements PrivValidator.
+func (privVal *PrivValidatorFS) SignProposal(chainID string, proposal *Proposal) error {
+	privVal.mtx.Lock()
+	defer privVal.mtx.Unlock()
+	signature, err := privVal.Info.SignBytesHRS(privVal.Signer,
+		proposal.Height, proposal.Round, stepPropose, SignBytes(chainID, proposal))
 	if err != nil {
-		cmn.Exit(cmn.Fmt("Error reading PrivValidator from %v: %v\n", filePath, err))
+		return fmt.Errorf("Error signing proposal: %v", err)
 	}
-
-	privVal.filePath = filePath
-	privVal.Signer = signerFunc(privVal.ID)
-	return &privVal
-}
-
-// Address returns the address of the validator.
-func (pv *PrivValidatorFS) Address() data.Bytes {
-	return pv.ID.Address
+	privVal.save()
+	proposal.Signature = signature
+	return nil
 }
 
-// PubKey returns the public key of the validator.
-func (pv *PrivValidatorFS) PubKey() crypto.PubKey {
-	return pv.ID.PubKey
+// SignHeartbeat signs a canonical representation of the heartbeat, along with the chainID.
+// Implements PrivValidator.
+func (privVal *PrivValidatorFS) SignHeartbeat(chainID string, heartbeat *Heartbeat) error {
+	privVal.mtx.Lock()
+	defer privVal.mtx.Unlock()
+	var err error
+	heartbeat.Signature, err = privVal.Signer.Sign(SignBytes(chainID, heartbeat))
+	return err
 }
 
 // Save persists the PrivValidatorFS to disk.
@@ -192,43 +172,102 @@ func (privVal *PrivValidatorFS) Reset() {
 	privVal.Save()
 }
 
-// SignVote signs a canonical representation of the vote, along with the chainID.
-func (privVal *PrivValidatorFS) SignVote(chainID string, vote *Vote) error {
-	privVal.mtx.Lock()
-	defer privVal.mtx.Unlock()
-	signature, err := privVal.signBytesHRS(vote.Height, vote.Round, voteToStep(vote), SignBytes(chainID, vote))
+// String returns a string representation of the PrivValidatorFS.
+func (privVal *PrivValidatorFS) String() string {
+	info := privVal.Info
+	return fmt.Sprintf("PrivValidator{%v LH:%v, LR:%v, LS:%v}", privVal.Address(), info.LastHeight, info.LastRound, info.LastStep)
+}
+
+// LoadOrGenPrivValidatorFS loads a PrivValidatorFS from the given filePath
+// or else generates a new one and saves it to the filePath.
+func LoadOrGenPrivValidatorFS(filePath string) *PrivValidatorFS {
+	var PrivValidatorFS *PrivValidatorFS
+	if _, err := os.Stat(filePath); err == nil {
+		PrivValidatorFS = LoadPrivValidatorFS(filePath)
+	} else {
+		PrivValidatorFS = GenPrivValidatorFS(filePath)
+		PrivValidatorFS.Save()
+	}
+	return PrivValidatorFS
+}
+
+// LoadPrivValidatorFS loads a PrivValidatorFS from the filePath.
+func LoadPrivValidatorFS(filePath string) *PrivValidatorFS {
+	privValJSONBytes, err := ioutil.ReadFile(filePath)
 	if err != nil {
-		return errors.New(cmn.Fmt("Error signing vote: %v", err))
+		cmn.Exit(err.Error())
 	}
-	vote.Signature = signature
-	return nil
+	privVal := PrivValidatorFS{}
+	err = json.Unmarshal(privValJSONBytes, &privVal)
+	if err != nil {
+		cmn.Exit(cmn.Fmt("Error reading PrivValidator from %v: %v\n", filePath, err))
+	}
+
+	privVal.filePath = filePath
+	return &privVal
 }
 
-// SignProposal signs a canonical representation of the proposal, along with the chainID.
-func (privVal *PrivValidatorFS) SignProposal(chainID string, proposal *Proposal) error {
-	privVal.mtx.Lock()
-	defer privVal.mtx.Unlock()
-	signature, err := privVal.signBytesHRS(proposal.Height, proposal.Round, stepPropose, SignBytes(chainID, proposal))
+// GenPrivValidatorFS generates a new validator with randomly generated private key
+// and sets the filePath, but does not call Save().
+func GenPrivValidatorFS(filePath string) *PrivValidatorFS {
+	privKey := crypto.GenPrivKeyEd25519().Wrap()
+	return &PrivValidatorFS{
+		ID: ValidatorID{privKey.PubKey().Address(), privKey.PubKey()},
+		Info: LastSignedInfo{
+			LastStep: stepNone,
+		},
+		Signer:   NewDefaultSigner(privKey),
+		filePath: filePath,
+	}
+}
+
+// LoadPrivValidatorWithSigner loads a PrivValidatorFS with a custom
+// signer object. The PrivValidatorFS handles double signing prevention by persisting
+// data to the filePath, while the Signer handles the signing.
+// If the filePath does not exist, the PrivValidatorFS must be created manually and saved.
+func LoadPrivValidatorFSWithSigner(filePath string, signerFunc func(ValidatorID) Signer) *PrivValidatorFS {
+	privValJSONBytes, err := ioutil.ReadFile(filePath)
 	if err != nil {
-		return fmt.Errorf("Error signing proposal: %v", err)
+		cmn.Exit(err.Error())
 	}
-	proposal.Signature = signature
-	return nil
+	privVal := PrivValidatorFS{}
+	err = json.Unmarshal(privValJSONBytes, &privVal)
+	if err != nil {
+		cmn.Exit(cmn.Fmt("Error reading PrivValidator from %v: %v\n", filePath, err))
+	}
+
+	privVal.filePath = filePath
+	privVal.Signer = signerFunc(privVal.ID)
+	return &privVal
 }
 
-// SignHeartbeat signs a canonical representation of the heartbeat, along with the chainID.
-func (privVal *PrivValidatorFS) SignHeartbeat(chainID string, heartbeat *Heartbeat) error {
-	privVal.mtx.Lock()
-	defer privVal.mtx.Unlock()
-	var err error
-	heartbeat.Signature, err = privVal.Signer.Sign(SignBytes(chainID, heartbeat))
-	return err
+//-------------------------------------
+
+// ValidatorID contains the identity of the validator.
+type ValidatorID struct {
+	Address data.Bytes    `json:"address"`
+	PubKey  crypto.PubKey `json:"pub_key"`
 }
 
-// check if there's a regression. Else sign and write the hrs+signature to disk
-func (privVal *PrivValidatorFS) signBytesHRS(height, round int, step int8, signBytes []byte) (crypto.Signature, error) {
+//-------------------------------------
+
+// LastSignedInfo contains information about the latest
+// data signed by a validator to help prevent double signing.
+type LastSignedInfo struct {
+	LastHeight    int              `json:"last_height"`
+	LastRound     int              `json:"last_round"`
+	LastStep      int8             `json:"last_step"`
+	LastSignature crypto.Signature `json:"last_signature,omitempty"` // so we dont lose signatures
+	LastSignBytes data.Bytes       `json:"last_signbytes,omitempty"` // so we dont lose signatures
+}
+
+// SignBytesHRS signs the given signBytes with the signer if the height/round/step (HRS)
+// are greater than the latest state of the LastSignedInfo. If the HRS are equal,
+// it returns the LastSignedInfo.LastSignature.
+func (info *LastSignedInfo) SignBytesHRS(signer Signer,
+	height, round int, step int8, signBytes []byte) (crypto.Signature, error) {
+
 	sig := crypto.Signature{}
-	info := privVal.Info
 	// If height regression, err
 	if info.LastHeight > height {
 		return sig, errors.New("Height regression")
@@ -262,46 +301,23 @@ func (privVal *PrivValidatorFS) signBytesHRS(height, round int, step int8, signB
 	}
 
 	// Sign
-	sig, err := privVal.Signer.Sign(signBytes)
+	sig, err := signer.Sign(signBytes)
 	if err != nil {
 		return sig, err
 	}
 
 	// Persist height/round/step
-	privVal.Info.LastHeight = height
-	privVal.Info.LastRound = round
-	privVal.Info.LastStep = step
-	privVal.Info.LastSignature = sig
-	privVal.Info.LastSignBytes = signBytes
-	privVal.save()
+	info.LastHeight = height
+	info.LastRound = round
+	info.LastStep = step
+	info.LastSignature = sig
+	info.LastSignBytes = signBytes
 
 	return sig, nil
 }
 
-// String returns a string representation of the PrivValidatorFS.
-func (privVal *PrivValidatorFS) String() string {
-	info := privVal.Info
-	return fmt.Sprintf("PrivValidator{%v LH:%v, LR:%v, LS:%v}", privVal.Address(), info.LastHeight, info.LastRound, info.LastStep)
-}
-
 //-------------------------------------
 
-// ValidatorID contains the identity of the validator.
-type ValidatorID struct {
-	Address data.Bytes    `json:"address"`
-	PubKey  crypto.PubKey `json:"pub_key"`
-}
-
-// LastSignedInfo contains information about the latest
-// data signed by a validator to help prevent double signing.
-type LastSignedInfo struct {
-	LastHeight    int              `json:"last_height"`
-	LastRound     int              `json:"last_round"`
-	LastStep      int8             `json:"last_step"`
-	LastSignature crypto.Signature `json:"last_signature,omitempty"` // so we dont lose signatures
-	LastSignBytes data.Bytes       `json:"last_signbytes,omitempty"` // so we dont lose signatures
-}
-
 // Signer is an interface that defines how to sign messages.
 // It is the caller's duty to verify the msg before calling Sign,
 // eg. to avoid double signing.