crypto: generator must be int32 in DiffieHellman()

Validate the generator argument in `crypto.createDiffieHellman(key, g)`.
When it's a number, it should be an int32.

Fixes: #32748

PR-URL: #32739
Fixes: #32738
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Zeyu Yang <himself65@outlook.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: James M Snell <jasnell@gmail.com>

lib/internal/crypto/diffiehellman.js

@@ -77,7 +77,9 @@ function DiffieHellman(sizeOrKey, keyEncoding, generator, genEncoding) {
 
   if (!generator)
     generator = DH_GENERATOR;
-  else if (typeof generator !== 'number')
+  else if (typeof generator === 'number')
+    validateInt32(generator, 'generator');
+  else
     generator = toBuf(generator, genEncoding);
 
   this[kHandle] = new _DiffieHellman(sizeOrKey, generator);

test/parallel/test-crypto-dh.js

@@ -30,6 +30,13 @@ assert.throws(() => crypto.createDiffieHellman(13.37), {
            'It must be an integer. Received 13.37',
 });
 
+assert.throws(() => crypto.createDiffieHellman('abcdef', 13.37), {
+  code: 'ERR_OUT_OF_RANGE',
+  name: 'RangeError',
+  message: 'The value of "generator" is out of range. ' +
+           'It must be an integer. Received 13.37',
+});
+
 for (const bits of [-1, 0, 1]) {
   assert.throws(() => crypto.createDiffieHellman(bits), {
     code: 'ERR_OSSL_BN_BITS_TOO_SMALL',