crypto.go

package util

import (
	"crypto"
	"crypto/hmac"
	"crypto/md5"
	"crypto/sha1"
	"crypto/sha256"
	"encoding/base64"
	"encoding/hex"
	"errors"
	"io"
	"os"
)

var (
	ErrUnavailable = errors.New("unavailable")
)

// sha1加密
func SHA1(str string) string {
	sha1Ctx := sha1.New()
	sha1Ctx.Write([]byte(str))
	cipherStr := sha1Ctx.Sum(nil)
	return hex.EncodeToString(cipherStr)
}

// sha1加密文件
func SHA1File(file string) string {
	if f, e := os.Open(file); e == nil {
		defer f.Close()

		h := sha1.New()
		if _, e := io.Copy(h, f); e == nil {
			return hex.EncodeToString(h.Sum(nil))
		}
	}
	return ""
}

func SHA1FileBase64(file string) string {
	if f, e := os.Open(file); e == nil {
		defer f.Close()

		h := sha1.New()
		if _, e := io.Copy(h, f); e == nil {
			return base64.URLEncoding.EncodeToString(h.Sum(nil))
		}
	}
	return ""
}

// SHA256
func SHA256(str string) string {
	sha256Ctx := sha256.New()
	sha256Ctx.Write([]byte(str))
	cipherStr := sha256Ctx.Sum(nil)
	return hex.EncodeToString(cipherStr)
}

// sha256加密文件
func SHA256File(file string) string {
	if f, e := os.Open(file); e == nil {
		defer f.Close()

		h := sha256.New()
		if _, e := io.Copy(h, f); e == nil {
			return hex.EncodeToString(h.Sum(nil))
		}
	}
	return ""
}

func SHA256FileBase64(file string) string {
	if f, e := os.Open(file); e == nil {
		defer f.Close()

		h := sha256.New()
		if _, e := io.Copy(h, f); e == nil {
			return base64.URLEncoding.EncodeToString(h.Sum(nil))
		}
	}
	return ""
}

// MD5
func MD5(str string) string {
	md5Ctx := md5.New()
	md5Ctx.Write([]byte(str))
	cipherStr := md5Ctx.Sum(nil)
	return hex.EncodeToString(cipherStr)
}

// MD5File
func MD5File(file string) string {
	if f, e := os.Open(file); e == nil {
		defer f.Close()

		h := md5.New()
		if _, e := io.Copy(h, f); e == nil {
			return hex.EncodeToString(h.Sum(nil))
		}
	}
	return ""
}

func MD5FileBase64(file string) string {
	if f, e := os.Open(file); e == nil {
		defer f.Close()

		h := md5.New()
		if _, e := io.Copy(h, f); e == nil {
			return base64.URLEncoding.EncodeToString(h.Sum(nil))
		}
	}
	return ""
}

func HMACSign(data string, key string) (string, error) {
	if !crypto.SHA1.Available() {
		return "", ErrUnavailable
	}

	hasher := hmac.New(crypto.SHA1.New, []byte(key))
	hasher.Write([]byte(data))

	code := hasher.Sum(nil)

	return base64.URLEncoding.EncodeToString(code), nil
}

func HMACVerify(data, sign string, key string) error {
	if !crypto.SHA1.Available() {
		return ErrUnavailable
	}

	sig, err := base64.URLEncoding.DecodeString(sign)
	if err != nil {
		return err
	}

	hasher := hmac.New(crypto.SHA1.New, []byte(key))
	hasher.Write([]byte(data))
	if !hmac.Equal(sig, hasher.Sum(nil)) {
		return ErrUnavailable
	}

	return nil
}