http2: explicitly disallow nested push streams

Fixes: #19095 PR-URL: #22245 Reviewed-By: Matteo Collina <matteo.collina@gmail.com> Reviewed-By: Trivikram Kamat <trivikr.dev@gmail.com>
nodejs · Aug 10, 2018 · 7223a91a50800588b8dcc81af662f36cbb482816 · 7223a91
1 parent f570c19
commit 7223a91a50800588b8dcc81af662f36cbb482816
Unified Split

Showing with 22 additions and 0 deletions.

+6 −0 doc/api/errors.md

+3 −0 doc/api/http2.md

+2 −0 lib/internal/errors.js

+3 −0 lib/internal/http2/core.js

+8 −0 test/parallel/test-http2-server-push-stream.js
diff --git a/doc/api/errors.md b/doc/api/errors.md
@@ -956,6 +956,12 @@ required to send an acknowledgment that it has received and applied the new
 be sent at any given time. This error code is used when that limit has been
 reached.
+  
+<a id="ERR_HTTP2_NESTED_PUSH"></a>
+  
+### ERR_HTTP2_NESTED_PUSH
+  
+
+  
+An attempt was made to initiate a new push stream from within a push stream.
+  
+Nested push streams are not permitted.
+  
+
 <a id="ERR_HTTP2_NO_SOCKET_MANIPULATION"></a>
 ### ERR_HTTP2_NO_SOCKET_MANIPULATION

diff --git a/doc/api/http2.md b/doc/api/http2.md
@@ -1256,6 +1256,9 @@ Setting the weight of a push stream is not allowed in the `HEADERS` frame. Pass
 a `weight` value to `http2stream.priority` with the `silent` option set to
 `true` to enable server-side bandwidth balancing between concurrent streams.
+  
+Calling `http2stream.pushStream()` from within a pushed stream is not permitted
+  
+and will throw an error.
+  
+
 #### http2stream.respond([headers[, options]])
 <!-- YAML
 added: v8.4.0

diff --git a/lib/internal/errors.js b/lib/internal/errors.js
@@ -568,6 +568,8 @@ E('ERR_HTTP2_INVALID_SETTING_VALUE',
 E('ERR_HTTP2_INVALID_STREAM', 'The stream has been destroyed', Error);
 E('ERR_HTTP2_MAX_PENDING_SETTINGS_ACK',
  'Maximum number of pending settings acknowledgements', Error);
+  
+E('ERR_HTTP2_NESTED_PUSH',
+  
+  'A push stream cannot initiate another push stream.', Error);
 E('ERR_HTTP2_NO_SOCKET_MANIPULATION',
  'HTTP/2 sockets should not be directly manipulated (e.g. read and written)',
  Error);

diff --git a/lib/internal/http2/core.js b/lib/internal/http2/core.js
@@ -47,6 +47,7 @@ const {
    ERR_HTTP2_INVALID_SETTING_VALUE,
    ERR_HTTP2_INVALID_STREAM,
    ERR_HTTP2_MAX_PENDING_SETTINGS_ACK,
+  
+    ERR_HTTP2_NESTED_PUSH,
    ERR_HTTP2_NO_SOCKET_MANIPULATION,
    ERR_HTTP2_OUT_OF_STREAMS,
    ERR_HTTP2_PAYLOAD_FORBIDDEN,
@@ -2158,6 +2159,8 @@ class ServerHttp2Stream extends Http2Stream {
  pushStream(headers, options, callback) {
    if (!this.pushAllowed)
      throw new ERR_HTTP2_PUSH_DISABLED();
+  
+    if (this[kID] % 2 === 0)
+  
+      throw new ERR_HTTP2_NESTED_PUSH();
    const session = this[kSession];

diff --git a/test/parallel/test-http2-server-push-stream.js b/test/parallel/test-http2-server-push-stream.js
@@ -22,6 +22,14 @@ server.on('stream', common.mustCall((stream, headers) => {
        'x-push-data': 'pushed by server',
      });
      push.end('pushed by server data');
+  
+
+  
+      common.expectsError(() => {
+  
+        push.pushStream({}, common.mustNotCall());
+  
+      }, {
+  
+        code: 'ERR_HTTP2_NESTED_PUSH',
+  
+        type: Error
+  
+      });
+  
+
      stream.end('test');
    }));
  }