src: compare IPv4 addresses in host byte order

This commit updates compare_ipv4() to use the host byte
order.

PR-URL: nodejs#39096
Fixes: nodejs#39074
Reviewed-By: Khaidi Chu <i@2333.moe>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>

src/node_sockaddr.cc

@@ -159,10 +159,12 @@ SocketAddress::CompareResult compare_ipv4(
       reinterpret_cast<const sockaddr_in*>(one.data());
   const sockaddr_in* two_in =
       reinterpret_cast<const sockaddr_in*>(two.data());
+  const uint32_t s_addr_one = ntohl(one_in->sin_addr.s_addr);
+  const uint32_t s_addr_two = ntohl(two_in->sin_addr.s_addr);
 
-  if (one_in->sin_addr.s_addr < two_in->sin_addr.s_addr)
+  if (s_addr_one < s_addr_two)
     return SocketAddress::CompareResult::LESS_THAN;
-  else if (one_in->sin_addr.s_addr == two_in->sin_addr.s_addr)
+  else if (s_addr_one == s_addr_two)
     return SocketAddress::CompareResult::SAME;
   else
     return SocketAddress::CompareResult::GREATER_THAN;

test/parallel/test-blocklist.js

@@ -209,6 +209,27 @@ const util = require('util');
   assert(!blockList.check('8592:757c:efaf:2fff:ffff:ffff:ffff:ffff', 'ipv6'));
 }
 
+{
+  // Regression test for https://github.com/nodejs/node/issues/39074
+  const blockList = new BlockList();
+
+  blockList.addRange('10.0.0.2', '10.0.0.10');
+
+  // IPv4 checks against IPv4 range.
+  assert(blockList.check('10.0.0.2'));
+  assert(blockList.check('10.0.0.10'));
+  assert(!blockList.check('192.168.0.3'));
+  assert(!blockList.check('2.2.2.2'));
+  assert(!blockList.check('255.255.255.255'));
+
+  // IPv6 checks against IPv4 range.
+  assert(blockList.check('::ffff:0a00:0002', 'ipv6'));
+  assert(blockList.check('::ffff:0a00:000a', 'ipv6'));
+  assert(!blockList.check('::ffff:c0a8:0003', 'ipv6'));
+  assert(!blockList.check('::ffff:0202:0202', 'ipv6'));
+  assert(!blockList.check('::ffff:ffff:ffff', 'ipv6'));
+}
+
 {
   const blockList = new BlockList();
   assert.throws(() => blockList.addRange('1.1.1.2', '1.1.1.1'), /ERR_INVALID_ARG_VALUE/);