Bug 1601671 - make websocket support proxying on SOCKS/HTTPS, r=michal

This is something less hacky to the best of my knowledge. Both passing preferable proxy table and letting system setting handle `ws`/`wss` touch the code of all platforms, which is more fragile.

Differential Revision: https://phabricator.services.mozilla.com/D57176

--HG--
extra : moz-landing-system : lando

netwerk/base/nsProtocolProxyService.cpp

@@ -2109,7 +2109,26 @@ nsresult nsProtocolProxyService::Resolve_Internal(nsIChannel* channel,
     // now try the system proxy settings for this particular url
     if (NS_SUCCEEDED(mSystemProxySettings->GetProxyForURI(spec, scheme, host,
                                                           port, pacString))) {
-      ProcessPACString(pacString, 0, result);
+      nsCOMPtr<nsIProxyInfo> pi;
+      ProcessPACString(pacString, 0, getter_AddRefs(pi));
+
+      if (flags & RESOLVE_PREFER_SOCKS_PROXY &&
+          flags & RESOLVE_PREFER_HTTPS_PROXY) {
+        nsAutoCString type;
+        pi->GetType(type);
+        // DIRECT from ProcessPACString indicates that system proxy settings
+        // are not configured to use SOCKS proxy. Try https proxy as a
+        // secondary preferrable proxy. This is mainly for websocket whose
+        // proxy precedence is SOCKS > HTTPS > DIRECT.
+        if (type.EqualsLiteral(kProxyType_DIRECT)) {
+          scheme.AssignLiteral(kProxyType_HTTPS);
+          if (NS_SUCCEEDED(mSystemProxySettings->GetProxyForURI(
+                  spec, scheme, host, port, pacString))) {
+            ProcessPACString(pacString, 0, getter_AddRefs(pi));
+          }
+        }
+      }
+      pi.forget(result);
       return NS_OK;
     }
   }

netwerk/test/unit/test_bug1177909.js

@@ -22,9 +22,12 @@ XPCOMUtils.defineLazyGetter(this, "systemSettings", function() {
       if (aPort != -1) {
         return "SOCKS5 http://localhost:9050";
       }
-      if (aScheme == "http" || aScheme == "https" || aScheme == "ftp") {
+      if (aScheme == "http" || aScheme == "ftp") {
         return "PROXY http://localhost:8080";
       }
+      if (aScheme == "https") {
+        return "HTTPS https://localhost:8080";
+      }
       return "DIRECT";
     },
   };
@@ -79,7 +82,7 @@ add_task(async function testHttpsProxy() {
   let pi = await TestProxyTypeByURI("https://www.mozilla.org/");
   equal(pi.host, "localhost", "Expected proxy host to be localhost");
   equal(pi.port, 8080, "Expected proxy port to be 8080");
-  equal(pi.type, "http", "Expected proxy type to be http");
+  equal(pi.type, "https", "Expected proxy type to be https");
 });
 
 add_task(async function testFtpProxy() {
@@ -137,6 +140,7 @@ add_task(async function testWebSocketProxy() {
     .finalize();
 
   let proxyFlags =
+    Ci.nsIProtocolProxyService.RESOLVE_PREFER_SOCKS_PROXY |
     Ci.nsIProtocolProxyService.RESOLVE_PREFER_HTTPS_PROXY |
     Ci.nsIProtocolProxyService.RESOLVE_ALWAYS_TUNNEL;
 
@@ -157,5 +161,32 @@ add_task(async function testWebSocketProxy() {
   let pi = await TestProxyType(chan, proxyFlags);
   equal(pi.host, "localhost", "Expected proxy host to be localhost");
   equal(pi.port, 8080, "Expected proxy port to be 8080");
-  equal(pi.type, "http", "Expected proxy type to be http");
+  equal(pi.type, "https", "Expected proxy type to be https");
+});
+
+add_task(async function testPreferHttpsProxy() {
+  let uri = Cc["@mozilla.org/network/standard-url-mutator;1"]
+    .createInstance(Ci.nsIURIMutator)
+    .setSpec("http://mozilla.org/")
+    .finalize();
+  let proxyFlags = Ci.nsIProtocolProxyService.RESOLVE_PREFER_HTTPS_PROXY;
+
+  let ioService = Cc["@mozilla.org/network/io-service;1"].getService(
+    Ci.nsIIOService
+  );
+  let chan = ioService.newChannelFromURIWithProxyFlags(
+    uri,
+    null,
+    proxyFlags,
+    null,
+    Services.scriptSecurityManager.getSystemPrincipal(),
+    null,
+    Ci.nsILoadInfo.SEC_ALLOW_CROSS_ORIGIN_DATA_IS_NULL,
+    Ci.nsIContentPolicy.TYPE_OTHER
+  );
+
+  let pi = await TestProxyType(chan, proxyFlags);
+  equal(pi.host, "localhost", "Expected proxy host to be localhost");
+  equal(pi.port, 8080, "Expected proxy port to be 8080");
+  equal(pi.type, "https", "Expected proxy type to be https");
 });