archived-rttys/utils.go

package main

import (
	"bytes"
	"crypto/md5"
	"crypto/rand"
	"encoding/binary"
	"encoding/hex"
	"fmt"
	"github.com/howeyc/gopass"
	"github.com/rs/zerolog/log"
	"io"
	"os"
	"time"
)

func bytesToIntU(b []byte) int {
	if len(b) == 3 {
		b = append([]byte{0}, b...)
	}
	bytesBuffer := bytes.NewBuffer(b)
	switch len(b) {
	case 1:
		var tmp uint8
		binary.Read(bytesBuffer, binary.BigEndian, &tmp)
		return int(tmp)
	case 2:
		var tmp uint16
		binary.Read(bytesBuffer, binary.BigEndian, &tmp)
		return int(tmp)
	case 4:
		var tmp uint32
		binary.Read(bytesBuffer, binary.BigEndian, &tmp)
		return int(tmp)
	default:
		return 0
	}
}

func intToBytes(n int, b byte) []byte {
	switch b {
	case 1:
		tmp := int8(n)
		bytesBuffer := bytes.NewBuffer([]byte{})
		binary.Write(bytesBuffer, binary.BigEndian, &tmp)
		return bytesBuffer.Bytes()
	case 2:
		tmp := int16(n)
		bytesBuffer := bytes.NewBuffer([]byte{})
		binary.Write(bytesBuffer, binary.BigEndian, &tmp)
		return bytesBuffer.Bytes()
	case 3, 4:
		tmp := int32(n)
		bytesBuffer := bytes.NewBuffer([]byte{})
		binary.Write(bytesBuffer, binary.BigEndian, &tmp)
		return bytesBuffer.Bytes()
	}
	return []byte{}
}

func genUniqueID(extra string) string {
	buf := make([]byte, 20)

	binary.BigEndian.PutUint32(buf, uint32(time.Now().Unix()))
	io.ReadFull(rand.Reader, buf[4:])

	h := md5.New()
	h.Write(buf)
	h.Write([]byte(extra))

	return hex.EncodeToString(h.Sum(nil))
}

func genTokenAndExit() {
	password, err := gopass.GetPasswdPrompt("Please set a password:", true, os.Stdin, os.Stdout)
	if err != nil {
		log.Fatal().Msg(err.Error())
	}

	token := genUniqueID(string(password))

	fmt.Println("Your token is:", token)

	os.Exit(0)
}