From c6ac6f2ea1480623d2c654db65ee7445041f635d Mon Sep 17 00:00:00 2001
From: Mihai Potra <mike@mpotra.com>
Date: Fri, 19 Feb 2016 10:21:49 +0200
Subject: [PATCH] http: Corrects IPv6 address in Host header

IPv6 addresses in Host header (URI), must be enclosed within
square brackets, in order to properly separate the host address
from any port reference.

PR-URL: https://github.com/nodejs/node/pull/5314
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Evan Lucas <evanlucas@me.com>
---
 lib/_http_client.js                           | 11 +++++
 .../test-http-host-header-ipv6-fail.js        | 40 +++++++++++++++++++
 2 files changed, 51 insertions(+)
 create mode 100644 test/parallel/test-http-host-header-ipv6-fail.js

diff --git a/lib/_http_client.js b/lib/_http_client.js
index cd4ce0e9cd3426..e051ebe5fdb01c 100644
--- a/lib/_http_client.js
+++ b/lib/_http_client.js
@@ -87,6 +87,17 @@ function ClientRequest(options, cb) {
     }
     if (host && !this.getHeader('host') && setHost) {
       var hostHeader = host;
+      var posColon = -1;
+
+      // For the Host header, ensure that IPv6 addresses are enclosed
+      // in square brackets, as defined by URI formatting
+      // https://tools.ietf.org/html/rfc3986#section-3.2.2
+      if (-1 !== (posColon = hostHeader.indexOf(':')) &&
+          -1 !== (posColon = hostHeader.indexOf(':', posColon)) &&
+          '[' !== hostHeader[0]) {
+        hostHeader = `[${hostHeader}]`;
+      }
+
       if (port && +port !== defaultPort) {
         hostHeader += ':' + port;
       }
diff --git a/test/parallel/test-http-host-header-ipv6-fail.js b/test/parallel/test-http-host-header-ipv6-fail.js
new file mode 100644
index 00000000000000..8a1a9a61afe5af
--- /dev/null
+++ b/test/parallel/test-http-host-header-ipv6-fail.js
@@ -0,0 +1,40 @@
+'use strict';
+/*
+ * When using the object form of http.request and using an IPv6 address
+ * as a hostname, and using a non-standard port, the Host header
+ * is improperly formatted.
+ * Issue: https://github.com/nodejs/node/issues/5308
+ * As per https://tools.ietf.org/html/rfc7230#section-5.4 and
+ * https://tools.ietf.org/html/rfc3986#section-3.2.2
+ * the IPv6 address should be enclosed in square brackets
+ */
+
+const common = require('../common');
+const assert = require('assert');
+const http = require('http');
+
+const hostname = '::1';
+const port = common.PORT;
+
+function httpreq() {
+  var req = http.request({
+    host: hostname,
+    port: port,
+    path: '/',
+    method: 'GET'
+  });
+  req.end();
+}
+
+if (!common.hasIPv6) {
+  console.error('Skipping test, no IPv6 support');
+  return;
+}
+
+const server = http.createServer(common.mustCall(function(req, res) {
+  assert.ok(req.headers.host, `[${hostname}]`);
+  res.end();
+  server.close(true);
+}));
+
+server.listen(port, hostname, () => httpreq());