http2: pause input processing if sending output

If we are waiting for the ability to send more output, we should not
process more input. This commit a) makes us send output earlier,
during processing of input, if we accumulate a lot and b) allows
interrupting the call into nghttp2 that processes input data
and resuming it at a later time, if we do find ourselves in a position
where we are waiting to be able to send more output.

This is part of mitigating CVE-2019-9511/CVE-2019-9517.

PR-URL: https://github.com/nodejs/node/pull/29122
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

1 files changed, 39 insertions, 0 deletions

diff --git a/test/parallel/test-http2-large-write-multiple-requests.js b/test/parallel/test-http2-large-write-multiple-requests.js
new file mode 100644
index 0000000000..0d65c3479b
--- /dev/null
+++ b/test/parallel/test-http2-large-write-multiple-requests.js
@@ -0,0 +1,39 @@
+'use strict';
+const common = require('../common');
+if (!common.hasCrypto)
+  common.skip('missing crypto');
+
+const fixtures = require('../common/fixtures');
+const assert = require('assert');
+const http2 = require('http2');
+
+const content = fixtures.readSync('person-large.jpg');
+
+const server = http2.createServer({
+  maxSessionMemory: 1000
+});
+server.on('stream', (stream, headers) => {
+  stream.respond({
+    'content-type': 'image/jpeg',
+    ':status': 200
+  });
+  stream.end(content);
+});
+server.unref();
+
+server.listen(0, common.mustCall(() => {
+  const client = http2.connect(`http://localhost:${server.address().port}/`);
+
+  let finished = 0;
+  for (let i = 0; i < 100; i++) {
+    const req = client.request({ ':path': '/' }).end();
+    const chunks = [];
+    req.on('data', (chunk) => {
+      chunks.push(chunk);
+    });
+    req.on('end', common.mustCall(() => {
+      assert.deepStrictEqual(Buffer.concat(chunks), content);
+      if (++finished === 100) client.close();
+    }));
+  }
+}));