internal/ethapi: reject non-replay-protected txs over RPC (#22339)

This PR prevents users from submitting transactions without EIP-155 enabled. This behaviour can be overridden by specifying the flag --rpc.allow-unprotected-txs=true.

les/api_backend.go

@@ -40,9 +40,10 @@ import (
 )
 
 type LesApiBackend struct {
-	extRPCEnabled bool
-	eth           *LightEthereum
-	gpo           *gasprice.Oracle
+	extRPCEnabled       bool
+	allowUnprotectedTxs bool
+	eth                 *LightEthereum
+	gpo                 *gasprice.Oracle
 }
 
 func (b *LesApiBackend) ChainConfig() *params.ChainConfig {
@@ -263,6 +264,10 @@ func (b *LesApiBackend) ExtRPCEnabled() bool {
 	return b.extRPCEnabled
 }
 
+func (b *LesApiBackend) UnprotectedAllowed() bool {
+	return b.allowUnprotectedTxs
+}
+
 func (b *LesApiBackend) RPCGasCap() uint64 {
 	return b.eth.config.RPCGasCap
 }