https: do not automatically use invalid servername

sam-github · sam-github · commit 9bbc7d9989b0 · 2019-06-14T12:03:49.000-07:00
Stop automatically setting servername in https.request() if the target
host is specified with an IP address. Doing so is invalid, and triggers
a deprecation warning. It is still possible to send an IP address as a
servername if its required, but it needs to be explicity configured, it
won't happen automatically.
diff --git a/doc/api/https.md b/doc/api/https.md
@@ -24,15 +24,23 @@ An [`Agent`][] object for HTTPS similar to [`http.Agent`][]. See
 [`https.request()`][] for more information.
 
 ### new Agent([options])
-
+<!-- YAML
+changes:
+  - version: REPLACEME
+    pr-url: https://github.com/nodejs/node/pull/28209
+    description: do not automatically set servername if the target host was
+                 specified using an IP address.
+-->
 * `options` {Object} Set of configurable options to set on the agent.
   Can have the same fields as for [`http.Agent(options)`][], and
   * `maxCachedSessions` {number} maximum number of TLS cached sessions.
     Use `0` to disable TLS session caching. **Default:** `100`.
   * `servername` {string} the value of
     [Server Name Indication extension][sni wiki] to be sent to the server. Use
     empty string `''` to disable sending the extension.
-    **Default:** hostname or IP address of the target server.
+    **Default:** hostname of the target server, unless the target server
+    is specified using an IP address, in which case the default is `''` (no
+    extension).
 
     See [`Session Resumption`][] for infomation about TLS session reuse.
 
diff --git a/lib/_http_agent.js b/lib/_http_agent.js
@@ -256,6 +256,9 @@ function calculateServerName(options, req) {
       servername = hostHeader.split(':', 1)[0];
     }
   }
+  // Don't implicitly set invalid (IP) servernames.
+  if (net.isIP(servername))
+    servername = '';
   return servername;
 }
 
diff --git a/test/parallel/test-https-simple.js b/test/parallel/test-https-simple.js
@@ -29,6 +29,9 @@ if (!common.hasCrypto)
 const assert = require('assert');
 const https = require('https');
 
+// Assert that the IP-as-servername deprecation warning does not occur.
+process.on('warning', common.mustNotCall());
+
 const options = {
   key: fixtures.readKey('agent1-key.pem'),
   cert: fixtures.readKey('agent1-cert.pem')

Original file line number	Diff line number	Diff line change
`@@ -256,6 +256,9 @@ function calculateServerName(options, req) {`
`256`	`256`	`servername = hostHeader.split(':', 1)[0];`
`257`	`257`	`}`
`258`	`258`	`}`
	`259`	`+ // Don't implicitly set invalid (IP) servernames.`
	`260`	`+ if (net.isIP(servername))`
	`261`	`+ servername = '';`
`259`	`262`	`return servername;`
`260`	`263`	`}`
`261`	`264`