Nginx HTTP/2 over TLS 访问报 400，有熟悉的同学吗？

最近在写一个 HTTP/2 的代理。如果是不带 TLS 的话，是可以正常工作的，

    server {
        listen 8443 http2;

        location / {
            error_log /Users/jiajun/nginx_error_log.log debug;
            grpc_pass grpc://127.0.0.1:2017;
        }
    }

执行一下：

$ go run example/grpc_client/main.go
calling to 127.0.0.1:2019
2019/01/28 11:50:46 gonna call c.SayHello...
2019/01/28 11:50:46 Greeting: Hello world

Nginx 日志是:

127.0.0.1 - - [28/Jan/2019:11:50:46 +0800] "POST /helloworld.Greeter/SayHello HTTP/2.0" 200 18 "-" "grpc-go/1.16.0" "-"

加证书之后:

    server {
        listen 8443 ssl http2;
        ssl_certificate     /Users/jiajun/127.0.0.1.crt;
        ssl_certificate_key /Users/jiajun/127.0.0.1.key;

        location / {
            error_log /Users/jiajun/nginx_error_log.log debug;
            grpc_pass grpc://127.0.0.1:2017;
        }
    }

执行一下:

$ go run example/grpc_client/main.go
calling to 127.0.0.1:2019
2019/01/28 11:53:06 gonna call c.SayHello...
2019/01/28 11:53:06 could not greet: rpc error: code = Unavailable desc = transport is closing
exit status 1

Nginx 日志:

    127.0.0.1 - - [28/Jan/2019:11:53:06 +0800] "PRI * HTTP/2.0" 400 157 "-" "-" "-"

有同学遇到同样的问题吗？

此外，可以写一个简单的 demo 复现问题：

package main

import (
	"crypto/tls"
	"log"
)

func main() {
	backendConn, err := tls.Dial("tcp", "127.0.0.1:8443", &tls.Config{InsecureSkipVerify: true})
	if err != nil {
		log.Printf("failed to dial: %s", err)
	}

	if _, err := backendConn.Write([]byte("PRI * HTTP/2.0\r\n\r\nSM\r\n\r\n")); err != nil {
		log.Printf("failed to write: %s", err)
	}

	b := make([]byte, 4096)
	if _, err := backendConn.Read(b); err != nil {
		log.Printf("failed to read: %s", err)
	}

	log.Printf("result: %s", b)
}

结果：

$ go run main.go
2019/01/28 14:59:50 result: HTTP/1.1 400 Bad Request
Server: nginx/1.15.8
Date: Mon, 28 Jan 2019 06:59:50 GMT
Content-Type: text/html
Content-Length: 157
Connection: close

<html>
<head><title>400 Bad Request</title></head>
<body>
<center><h1>400 Bad Request</h1></center>
<hr><center>nginx/1.15.8</center>
</body>
</html>