utls.go

package main

import (
	"context"
	"crypto/tls"
	"fmt"
	"io"
	"net"
	"strings"

	"github.com/imroc/req/v3"
	utls "github.com/refraction-networking/utls"
)

type TLSConn struct {
	*utls.UConn
}

func (conn *TLSConn) ConnectionState() tls.ConnectionState {
	cs := conn.UConn.ConnectionState()
	return tls.ConnectionState{
		Version:                     cs.Version,
		HandshakeComplete:           cs.HandshakeComplete,
		DidResume:                   cs.DidResume,
		CipherSuite:                 cs.CipherSuite,
		NegotiatedProtocol:          cs.NegotiatedProtocol,
		NegotiatedProtocolIsMutual:  cs.NegotiatedProtocolIsMutual,
		ServerName:                  cs.ServerName,
		PeerCertificates:            cs.PeerCertificates,
		VerifiedChains:              cs.VerifiedChains,
		SignedCertificateTimestamps: cs.SignedCertificateTimestamps,
		OCSPResponse:                cs.OCSPResponse,
		TLSUnique:                   cs.TLSUnique,
	}
}

// curl https://tls.peet.ws/api/search-ja3?by=$(go run utls.go | jq -r ."tls"."ja3")
func main() {
	c := req.C()
	
	c.SetDialTLS(func(ctx context.Context, network, addr string) (net.Conn, error) {
		plainConn, err := net.Dial(network, addr)
		if err != nil {
			return nil, err
		}
		colonPos := strings.LastIndex(addr, ":")
		if colonPos == -1 {
			colonPos = len(addr)
		}
		hostname := addr[:colonPos]
		utlsConfig := &utls.Config{ServerName: hostname, NextProtos: c.GetTLSClientConfig().NextProtos}
		conn := utls.UClient(plainConn, utlsConfig, utls.HelloFirefox_Auto)
		return &TLSConn{conn}, nil
	})
	
	resp := c.R().MustGet("https://tls.peet.ws/api/all")
	fmt.Println(resp.String())
}