Move func VerifySig() to the crypto package

see #1325

core/orchestrator.go

@@ -25,6 +25,7 @@ import (
 	"github.com/livepeer/go-livepeer/net"
 	"github.com/livepeer/go-livepeer/pm"
 
+	lpcrypto "github.com/livepeer/go-livepeer/crypto"
 	lpmon "github.com/livepeer/go-livepeer/monitor"
 	ffmpeg "github.com/livepeer/lpms/ffmpeg"
 	"github.com/livepeer/lpms/stream"
@@ -67,7 +68,7 @@ func (orch *orchestrator) VerifySig(addr ethcommon.Address, msg string, sig []by
 	if orch.node == nil || orch.node.Eth == nil {
 		return true
 	}
-	return pm.VerifySig(addr, crypto.Keccak256([]byte(msg)), sig)
+	return lpcrypto.VerifySig(addr, crypto.Keccak256([]byte(msg)), sig)
 }
 
 func (orch *orchestrator) Address() ethcommon.Address {

crypto/verify.go

@@ -0,0 +1,56 @@
+package crypto
+
+import (
+	"errors"
+	"math/big"
+
+	"github.com/ethereum/go-ethereum/accounts"
+	ethcommon "github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/crypto"
+)
+
+var (
+	secp256k1N, _  = new(big.Int).SetString("fffffffffffffffffffffffffffffffebaaedce6af48a03bbfd25e8cd0364141", 16)
+	secp256k1halfN = new(big.Int).Div(secp256k1N, big.NewInt(2))
+)
+
+// Verify verifies that a ETH ECDSA signature over a given message
+// is produced by a given ETH address
+func VerifySig(addr ethcommon.Address, msg, sig []byte) bool {
+	recovered, err := ecrecover(msg, sig)
+	if err != nil {
+		return false
+	}
+
+	return recovered == addr
+}
+
+func ecrecover(msg, sig []byte) (ethcommon.Address, error) {
+	if len(sig) != 65 {
+		return ethcommon.Address{}, errors.New("invalid signature length")
+	}
+
+	s := new(big.Int).SetBytes(sig[32:64])
+	if s.Cmp(secp256k1halfN) > 0 {
+		return ethcommon.Address{}, errors.New("signature s value too high")
+	}
+
+	v := sig[64]
+	if v != byte(27) && v != byte(28) {
+		return ethcommon.Address{}, errors.New("signature v value must be 27 or 28")
+	}
+
+	// crypto.SigToPub() expects signature v value = 0/1
+	// Copy the signature and convert its value to 0/1
+	ethSig := make([]byte, 65)
+	copy(ethSig[:], sig[:])
+	ethSig[64] -= 27
+
+	ethMsg := accounts.TextHash(msg)
+	pubkey, err := crypto.SigToPub(ethMsg, ethSig)
+	if err != nil {
+		return ethcommon.Address{}, err
+	}
+
+	return crypto.PubkeyToAddress(*pubkey), nil
+}

pm/helpers_test.go → crypto/verify_test.go

@@ -1,4 +1,4 @@
-package pm
+package crypto
 
 import (
 	"testing"

eth/accountmanager_test.go

@@ -7,7 +7,7 @@ import (
 
 	"github.com/ethereum/go-ethereum/accounts/keystore"
 	"github.com/ethereum/go-ethereum/core/types"
-	"github.com/livepeer/go-livepeer/pm"
+	"github.com/livepeer/go-livepeer/crypto"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 )
@@ -93,7 +93,7 @@ func TestSign(t *testing.T) {
 
 	sig, err := am.Sign([]byte("foo"))
 	assert.Nil(err)
-	assert.True(pm.VerifySig(a.Address, []byte("foo"), sig))
+	assert.True(crypto.VerifySig(a.Address, []byte("foo"), sig))
 }
 
 func tmpKeyStore(t *testing.T, encrypted bool) (string, *keystore.KeyStore) {

pm/helpers.go

@@ -1,63 +1,11 @@
 package pm
 
 import (
-	"math/big"
 	"math/rand"
 
-	"github.com/ethereum/go-ethereum/accounts"
 	ethcommon "github.com/ethereum/go-ethereum/common"
-	"github.com/ethereum/go-ethereum/crypto"
-	"github.com/pkg/errors"
 )
 
-var (
-	secp256k1N, _  = new(big.Int).SetString("fffffffffffffffffffffffffffffffebaaedce6af48a03bbfd25e8cd0364141", 16)
-	secp256k1halfN = new(big.Int).Div(secp256k1N, big.NewInt(2))
-)
-
-// VerifySig verifies that a ETH ECDSA signature over a given message
-// is produced by a given ETH address
-//
-// TODO refactor to a package that both eth and pm can import
-func VerifySig(addr ethcommon.Address, msg, sig []byte) bool {
-	recovered, err := ecrecover(msg, sig)
-	if err != nil {
-		return false
-	}
-
-	return recovered == addr
-}
-
-func ecrecover(msg, sig []byte) (ethcommon.Address, error) {
-	if len(sig) != 65 {
-		return ethcommon.Address{}, errors.New("invalid signature length")
-	}
-
-	s := new(big.Int).SetBytes(sig[32:64])
-	if s.Cmp(secp256k1halfN) > 0 {
-		return ethcommon.Address{}, errors.New("signature s value too high")
-	}
-
-	v := sig[64]
-	if v != byte(27) && v != byte(28) {
-		return ethcommon.Address{}, errors.New("signature v value must be 27 or 28")
-	}
-
-	// crypto.SigToPub() expects signature v value = 0/1
-	// Copy the signature and convert its value to 0/1
-	ethSig := make([]byte, 65)
-	copy(ethSig[:], sig[:])
-	ethSig[64] -= 27
-
-	ethMsg := accounts.TextHash(msg)
-	pubkey, err := crypto.SigToPub(ethMsg, ethSig)
-	if err != nil {
-		return ethcommon.Address{}, err
-	}
-
-	return crypto.PubkeyToAddress(*pubkey), nil
-}
-
 // RandHash returns a random keccak256 hash
 func RandHash() ethcommon.Hash {
 	return ethcommon.BytesToHash(RandBytes(32))

pm/sigverifier.go

@@ -2,6 +2,7 @@ package pm
 
 import (
 	ethcommon "github.com/ethereum/go-ethereum/common"
+	"github.com/livepeer/go-livepeer/crypto"
 )
 
 // SigVerifier is an interface which describes an object capable
@@ -20,7 +21,7 @@ type DefaultSigVerifier struct {
 // Verify checks if a provided signature over a message
 // is valid for a given ETH address
 func (sv *DefaultSigVerifier) Verify(addr ethcommon.Address, msg, sig []byte) bool {
-	return VerifySig(addr, msg, sig)
+	return crypto.VerifySig(addr, msg, sig)
 }
 
 // ApprovedSigVerifier is an implementation of the SigVerifier interface

server/broadcast.go

@@ -18,10 +18,10 @@ import (
 
 	"github.com/livepeer/go-livepeer/common"
 	"github.com/livepeer/go-livepeer/core"
+	lpcrypto "github.com/livepeer/go-livepeer/crypto"
 	"github.com/livepeer/go-livepeer/drivers"
 	"github.com/livepeer/go-livepeer/monitor"
 	"github.com/livepeer/go-livepeer/net"
-	"github.com/livepeer/go-livepeer/pm"
 	"github.com/livepeer/go-livepeer/verification"
 
 	"github.com/livepeer/lpms/ffmpeg"
@@ -491,7 +491,7 @@ func transcodeSegment(cxn *rtmpConnection, seg *stream.HLSSegment, name string,
 		// Might not have seg hashes if results are directly uploaded to the broadcaster's OS
 		// TODO: Consider downloading the results to generate seg hashes if results are directly uploaded to the broadcaster's OS
 		len(segHashes) != len(res.Segments) &&
-		!pm.VerifySig(ethcommon.BytesToAddress(ticketParams.Recipient), crypto.Keccak256(segHashes...), res.Sig) {
+		!lpcrypto.VerifySig(ethcommon.BytesToAddress(ticketParams.Recipient), crypto.Keccak256(segHashes...), res.Sig) {
 		glog.Errorf("Sig check failed for segment nonce=%d seqNo=%d", nonce, seg.SeqNo)
 		cxn.sessManager.removeSession(sess)
 		return nil, errPMCheckFailed

server/rpc_test.go

@@ -23,6 +23,7 @@ import (
 
 	"github.com/livepeer/go-livepeer/common"
 	"github.com/livepeer/go-livepeer/core"
+	"github.com/livepeer/go-livepeer/crypto"
 	"github.com/livepeer/go-livepeer/drivers"
 	"github.com/livepeer/go-livepeer/net"
 	"github.com/livepeer/go-livepeer/pm"
@@ -96,7 +97,7 @@ func (r *stubOrchestrator) Sign(msg []byte) ([]byte, error) {
 }
 
 func (r *stubOrchestrator) VerifySig(addr ethcommon.Address, msg string, sig []byte) bool {
-	return pm.VerifySig(addr, ethcrypto.Keccak256([]byte(msg)), sig)
+	return crypto.VerifySig(addr, ethcrypto.Keccak256([]byte(msg)), sig)
 }
 
 func (r *stubOrchestrator) Address() ethcommon.Address {