TP-LINK路由器登录的RSA加密实现

cred.go

package tplink

import (
	"git.4z.ee/gleox/tplink/tplink/rsa"
)

const (
	modulus  = "D1E79FF135D14E342D76185C23024E6DEAD4D6EC2C317A526C811E83538EA4E5ED8E1B0EEE5CE26E3C1B6A5F1FE11FA804F28B7E8821CA90AFA5B2F300DF99FDA27C9D2131E031EA11463C47944C05005EF4C1CE932D7F4A87C7563581D9F27F0C305023FCE94997EC7D790696E784357ED803A610EBB71B12A8BE5936429BFD"
	exponent = "010001"
)

// GetSecret build login token
func GetSecret(password string) (string, error) {
	secret, err := rsa.Encrypt(password, modulus, exponent)
	if err != nil {
		return "", err
	}

	return secret, nil
}

encrypt.go

package rsa

import (
	"encoding/hex"
	"errors"
	"math/big"
	"strconv"
)

// https://golang.org/pkg/crypto/rsa/

// Golang RSA encrypt and decrypt example
// https://gist.github.com/miguelmota/3ea9286bd1d3c2a985b67cac4ba2130a

// Golang RSA Key Generation
// https://gist.github.com/sdorra/1c95de8cb80da31610d2ad767cd6f251

// Encrypt encrypts data with RSA
func Encrypt(msg string, modulus string, exponent string) (string, error) {
	n, err := decodeBigInt(modulus)
	if err != nil {
		return "", err
	}

	e, err := decodeHexInt(exponent)
	if err != nil {
		return "", err
	}

	m, err := nopadding([]rune(msg), (n.BitLen()+7)>>3)
	if err != nil {
		return "", err
	}

	c := modPow(m, big.NewInt(e), n)
	z := hex.EncodeToString(c.Bytes())
	return z, nil
}

// rsa.go/encrypt
func modPow(m *big.Int, e *big.Int, n *big.Int) *big.Int {
	c := new(big.Int)
	c.Exp(m, e, n)
	return c
}

// http://192.168.1.1/webpages/js/libs/encrypt.js
func nopadding(s []rune, n int) (*big.Int, error) {
	length := len(s)
	if length > n {
		return nil, errors.New("Message too long for RSA")
	}

	ba := make([]byte, n)
	i, j := 0, 0
	for i < length && j < n {
		c := s[i]
		i++
		if c < 128 {
			ba[j] = byte(c)
			j++
		} else if c > 127 && c < 2048 {
			ba[j] = byte((c & 63) | 128)
			j++
			ba[j] = byte((c >> 6) | 192)
			j++
		} else {
			ba[j] = byte((c & 63) | 128)
			j++
			ba[j] = byte(((c >> 6) & 63) | 128)
			j++
			ba[j] = byte((c >> 12) | 124)
		}
	}

	for j < n {
		ba[j] = 0
		j++
	}

	z := new(big.Int)
	z.SetBytes(ba)
	return z, nil
}

// Golang hex to big int
// https://gist.github.com/miguelmota/6e0b9a41adde6befd39690d1cf127636

// decodeBigInt decodes bigint from hex string
func decodeBigInt(s string) (*big.Int, error) {
	z := new(big.Int)
	_, flag := z.SetString(s, 16)
	if !flag {
		return nil, errors.New("Invalid hex string")
	}
	return z, nil
}

func decodeHexInt(s string) (int64, error) {
	return strconv.ParseInt(s, 16, 0)
}