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

1 files changed, 23 insertions, 7 deletions

diff --git a/cmd/utils/flags.go b/cmd/utils/flags.go
index a3602182a..bf20abe81 100644
--- a/cmd/utils/flags.go
+++ b/cmd/utils/flags.go
@@ -427,7 +427,11 @@ var (
 		Usage: "Password file to use for non-interactive password input",
 		Value: "",
 	}
-
+	ExternalSignerFlag = cli.StringFlag{
+		Name:  "signer",
+		Usage: "External signer (url or path to ipc file)",
+		Value: "",
+	}
 	VMEnableDebugFlag = cli.BoolFlag{
 		Name:  "vmdebug",
 		Usage: "Record information useful for VM and contract debugging",
@@ -990,11 +994,15 @@ func setEtherbase(ctx *cli.Context, ks *keystore.KeyStore, cfg *eth.Config) {
 	}
 	// Convert the etherbase into an address and configure it
 	if etherbase != "" {
-		account, err := MakeAddress(ks, etherbase)
-		if err != nil {
-			Fatalf("Invalid miner etherbase: %v", err)
+		if ks != nil {
+			account, err := MakeAddress(ks, etherbase)
+			if err != nil {
+				Fatalf("Invalid miner etherbase: %v", err)
+			}
+			cfg.Etherbase = account.Address
+		} else {
+			Fatalf("No etherbase configured")
 		}
-		cfg.Etherbase = account.Address
 	}
 }
 
@@ -1093,6 +1101,10 @@ func SetNodeConfig(ctx *cli.Context, cfg *node.Config) {
 	setNodeUserIdent(ctx, cfg)
 	setDataDir(ctx, cfg)
 
+	if ctx.GlobalIsSet(ExternalSignerFlag.Name) {
+		cfg.ExternalSigner = ctx.GlobalString(ExternalSignerFlag.Name)
+	}
+
 	if ctx.GlobalIsSet(KeyStoreDirFlag.Name) {
 		cfg.KeyStoreDir = ctx.GlobalString(KeyStoreDirFlag.Name)
 	}
@@ -1274,8 +1286,12 @@ func SetEthConfig(ctx *cli.Context, stack *node.Node, cfg *eth.Config) {
 	// Avoid conflicting network flags
 	checkExclusive(ctx, DeveloperFlag, TestnetFlag, RinkebyFlag, GoerliFlag)
 	checkExclusive(ctx, LightServFlag, SyncModeFlag, "light")
-
-	ks := stack.AccountManager().Backends(keystore.KeyStoreType)[0].(*keystore.KeyStore)
+	// Can't use both ephemeral unlocked and external signer
+	checkExclusive(ctx, DeveloperFlag, ExternalSignerFlag)
+	var ks *keystore.KeyStore
+	if keystores := stack.AccountManager().Backends(keystore.KeyStoreType); len(keystores) > 0 {
+		ks = keystores[0].(*keystore.KeyStore)
+	}
 	setEtherbase(ctx, ks, cfg)
 	setGPO(ctx, &cfg.GPO)
 	setTxPool(ctx, &cfg.TxPool)