accounts, eth, clique, signer: support for external signer API (#18079)

* accounts, eth, clique: implement external backend + move sighash calc to backend

* signer: implement account_Version on external API

* accounts/external: enable ipc, add copyright

* accounts, internal, signer: formatting

* node: go fmt

* flags: disallow --dev in combo with --externalsigner

* accounts: remove clique-specific signing method, replace with more generic

* accounts, consensus: formatting + fix error in tests

* signer/core: remove (test-) import cycle

* clique: remove unused import

* accounts: remove CliqueHash and avoid dependency on package crypto

* consensus/clique: unduplicate header encoding

3 files changed, 24 insertions, 13 deletions

diff --git a/signer/core/api.go b/signer/core/api.go
index e9a335785..e112df9c7 100644
--- a/signer/core/api.go
+++ b/signer/core/api.go
@@ -36,8 +36,14 @@ import (
 	"github.com/ethereum/go-ethereum/rlp"
 )
 
-// numberOfAccountsToDerive For hardware wallets, the number of accounts to derive
-const numberOfAccountsToDerive = 10
+const (
+	// numberOfAccountsToDerive For hardware wallets, the number of accounts to derive
+	numberOfAccountsToDerive = 10
+	// ExternalAPIVersion -- see extapi_changelog.md
+	ExternalAPIVersion = "4.0.0"
+	// InternalAPIVersion -- see intapi_changelog.md
+	InternalAPIVersion = "3.0.0"
+)
 
 // ExternalAPI defines the external API through which signing requests are made.
 type ExternalAPI interface {
@@ -55,6 +61,7 @@ type ExternalAPI interface {
 	// Should be moved to Internal API, in next phase when we have
 	// bi-directional communication
 	//Import(ctx context.Context, keyJSON json.RawMessage) (Account, error)
+	Version(ctx context.Context) (string, error)
 }
 
 // SignerUI specifies what method a UI needs to implement to be able to be used as a UI for the signer
@@ -539,7 +546,7 @@ func (api *SignerAPI) Sign(ctx context.Context, addr common.MixedcaseAddress, da
 		return nil, err
 	}
 	// Assemble sign the data with the wallet
-	signature, err := wallet.SignHashWithPassphrase(account, res.Password, sighash)
+	signature, err := wallet.SignTextWithPassphrase(account, res.Password, data)
 	if err != nil {
 		api.UI.ShowError(err.Error())
 		return nil, err
@@ -610,3 +617,9 @@ func (api *SignerAPI) Import(ctx context.Context, keyJSON json.RawMessage) (Acco
 	}
 	return Account{Typ: "Account", URL: acc.URL, Address: acc.Address}, nil
 }
+
+// Returns the external api version. This method does not require user acceptance. Available methods are
+// available via enumeration anyway, and this info does not contain user-specific data
+func (api *SignerAPI) Version(ctx context.Context) (string, error) {
+	return ExternalAPIVersion, nil
+}
diff --git a/signer/core/api_test.go b/signer/core/api_test.go
index a8aa23896..114470cf9 100644
--- a/signer/core/api_test.go
+++ b/signer/core/api_test.go
@@ -29,7 +29,6 @@ import (
 	"time"
 
 	"github.com/ethereum/go-ethereum/accounts/keystore"
-	"github.com/ethereum/go-ethereum/cmd/utils"
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/common/hexutil"
 	"github.com/ethereum/go-ethereum/core/types"
@@ -135,7 +134,7 @@ func setup(t *testing.T) (*SignerAPI, chan string) {
 
 	db, err := NewAbiDBFromFile("../../cmd/clef/4byte.json")
 	if err != nil {
-		utils.Fatalf(err.Error())
+		t.Fatal(err.Error())
 	}
 	var (
 		ui  = &HeadlessUI{controller}
diff --git a/signer/core/auditlog.go b/signer/core/auditlog.go
index 1f9c90918..0cb6c9c47 100644
--- a/signer/core/auditlog.go
+++ b/signer/core/auditlog.go
@@ -80,14 +80,13 @@ func (l *AuditLogger) Export(ctx context.Context, addr common.Address) (json.Raw
 	return j, e
 }
 
-//func (l *AuditLogger) Import(ctx context.Context, keyJSON json.RawMessage) (Account, error) {
-//	// Don't actually log the json contents
-//	l.log.Info("Import", "type", "request", "metadata", MetadataFromContext(ctx).String(),
-//		"keyJSON size", len(keyJSON))
-//	a, e := l.api.Import(ctx, keyJSON)
-//	l.log.Info("Import", "type", "response", "addr", a.String(), "error", e)
-//	return a, e
-//}
+func (l *AuditLogger) Version(ctx context.Context) (string, error) {
+	l.log.Info("Version", "type", "request", "metadata", MetadataFromContext(ctx).String())
+	data, err := l.api.Version(ctx)
+	l.log.Info("Version", "type", "response", "data", data, "error", err)
+	return data, err
+
+}
 
 func NewAuditLogger(path string, api ExternalAPI) (*AuditLogger, error) {
 	l := log.New("api", "signer")