为什么收到超大记录TLS错误？

Question

I'm trying to use go-xmpp to connect to DuckDuckGo's XMPP services.

Below is my test-case:

package main

import (
    "crypto/tls"
    "log"

    "github.com/mattn/go-xmpp"
)

const (
    svr = "dukgo.com"
    usr = "testtesttest"
    pwd = "test123"
)

func main() {
    xmpp.DefaultConfig = tls.Config{
        ServerName:         svr,
        InsecureSkipVerify: false,
    }

    options := xmpp.Options{
        Host:     svr,
        User:     usr,
        Password: pwd,
    }

    _, err := options.NewClient()
    if err != nil {
        log.Fatal(err)
    }
}

The log.Fatal block is being executed and returns the following error message:

2016/08/24 16:32:27 tls: oversized record received with length 28012
exit status 1

Googling the error points me towards an identical error in Docker, so that's not exactly helpful. What does this error mean? What can I do to fix this?

Answer 1

Like the example of the go-xmpp package you are using it expects the port too for the tls.

So with out it will try to connect to the HTTP end point and give you this error. You will see errors like this when the endpoint supports only HTTP or HTTPS with an unknown CA certificate.

Note that the package you are using also supports No TLS double check DuckGo xmpp requirements and change your code to match them.

Other posts like this

• tls: oversized record received with length XXXXX

Example

https://github.com/mattn/go-xmpp/blob/master/_example/example.go

// Server has the port
var server = flag.String("server", "talk.google.com:443", "server")
var username = flag.String("username", "", "username")
var password = flag.String("password", "", "password")
var status = flag.String("status", "xa", "status")
var statusMessage = flag.String("status-msg", "I for one welcome our new codebot overlords.", "status message")
var notls = flag.Bool("notls", false, "No TLS")
var debug = flag.Bool("debug", false, "debug output")
var session = flag.Bool("session", false, "use server session")

// Omitted code

var talk *xmpp.Client
var err error
options := xmpp.Options{Host: *server,
    User:          *username,
    Password:      *password,
    NoTLS:         *notls,
    Debug:         *debug,
    Session:       *session,
    Status:        *status,
    StatusMessage: *statusMessage,
}

talk, err = options.NewClient()