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.

cmd/utils/flags.go

@@ -593,6 +593,10 @@ var (
 		Name:  "preload",
 		Usage: "Comma separated list of JavaScript files to preload into the console",
 	}
+	AllowUnprotectedTxs = cli.BoolFlag{
+		Name:  "rpc.allow-unprotected-txs",
+		Usage: "Allow for unprotected (non EIP155 signed) transactions to be submitted via RPC",
+	}
 
 	// Network Settings
 	MaxPeersFlag = cli.IntFlag{
@@ -966,6 +970,9 @@ func setHTTP(ctx *cli.Context, cfg *node.Config) {
 	if ctx.GlobalIsSet(HTTPPathPrefixFlag.Name) {
 		cfg.HTTPPathPrefix = ctx.GlobalString(HTTPPathPrefixFlag.Name)
 	}
+	if ctx.GlobalIsSet(AllowUnprotectedTxs.Name) {
+		cfg.AllowUnprotectedTxs = ctx.GlobalBool(AllowUnprotectedTxs.Name)
+	}
 }
 
 // setGraphQL creates the GraphQL listener interface string from the set