crypto: turn impossible DH errors into assertions

PR-URL: #31934 Reviewed-By: Colin Ihrig <[email protected]> Reviewed-By: James M Snell <[email protected]> Reviewed-By: David Carlier <[email protected]> Reviewed-By: Ruben Bridgewater <[email protected]> Reviewed-By: Luigi Pinca <[email protected]> Reviewed-By: Shelley Vohr <[email protected]> Reviewed-By: Anna Henningsen <[email protected]> Reviewed-By: Rich Trott <[email protected]>

Author: tniessen

src/node_crypto.cc

@@ -5884,11 +5884,7 @@ void DiffieHellman::ComputeSecret(const FunctionCallbackInfo<Value>& args){
 
  ClearErrorOnReturn clear_error_on_return;
 
-if (args.Length() == 0){
-returnTHROW_ERR_MISSING_ARGS(
- env, "Other party's public key argument is mandatory");
- }
-
+CHECK_EQ(args.Length(), 1);
 THROW_AND_RETURN_IF_NOT_BUFFER(env, args[0], "Other party's public key");
  ArrayBufferViewContents<unsignedchar> key_buf(args[0].As<ArrayBufferView>());
  BignumPointer key(BN_bin2bn(key_buf.data(), key_buf.length(), nullptr));
@@ -5948,11 +5944,7 @@ void DiffieHellman::SetKey(const FunctionCallbackInfo<Value>& args,
 
 char errmsg[64];
 
-if (args.Length() == 0){
-snprintf(errmsg, sizeof(errmsg), "%s argument is mandatory", what);
-returnTHROW_ERR_MISSING_ARGS(env, errmsg);
- }
-
+CHECK_EQ(args.Length(), 1);
 if (!Buffer::HasInstance(args[0])){
 snprintf(errmsg, sizeof(errmsg), "%s must be a buffer", what);
 returnTHROW_ERR_INVALID_ARG_TYPE(env, errmsg);