Certificate retrieval possible resource exhaustion about tls-observatory

[0xdiba]

func worker(msg []byte, ch *amqp.Channel) {

  <-sem
  defer releaseSemaphore()

  certs, ip, err := tlsretriever.CheckHost(string(msg), "443", true) //<-sometimes code does not return 
  panicIf(err)
  if certs == nil {
      log.Println("no certificate retrieved from", string(msg))
          return
  }

After some debugging ( seeing that limiting the resources used does not solve the problem )
I observed random behavior regarding the actual certificate retrieval made. For example, using specific domains ( google.com and amazon.com ) and after several tests the calculated retrieval success rate was 1890-1995/2000 requests. No errors were printed from the checkhost function.

After some more debugging it seems that the code gets stuck here:

conn, err := tls.Dial("tcp", canonicalName, &config)

in the tlsretriever package.

Searching the TLS Go code I found that the default timeout for this connection is no timeout but it still
doesn't make sense to me that it happens only a couple of times.

[0xdiba]

We must see if the new implementation fixes anything
bd6992d