在做微信客服的接口对接时，第一步就是在微信客服后台配置自己的回调URL
微信客服会往URL上get请求数据，要求把GET中的加密参数解析出来，并且原样输出，才能验证成功
下面就是使用官方的xml 版sdk 实现这个验证的类库，与测试用例
代码语言：javascript复制package wechat_kf_sdk
// 创建微信客服API的封装结构体实例
func NewKefuWework(corpid string, corpsecret, Token, EncodingAESKey string) *KefuWework {
return &KefuWework{
corpid: corpid,
corpsecret: corpsecret,
Token: Token,
EncodingAESKey: EncodingAESKey,
}
}
//验证签名
func (s *KefuWework) CheckSign(signature, timestamp, nonce, echostr string) (string, error) {
wxcpt := NewWXBizMsgCrypt(s.Token, s.EncodingAESKey, s.corpid, XmlType)
echoStr, cryptErr := wxcpt.VerifyURL(signature, timestamp, nonce, echostr)
if cryptErr != nil {
return "", errors.New(cryptErr.ErrMsg)
}
return string(echoStr), nil
}测试用例
代码语言：javascript复制func TestCheckSign(t *testing.T) {
corpid := "wx5823bf96d3bd56c7"
corpsecret := "your_corpsecret"
token := "QDG6eK"
encodingAeskey := "jWmYm7qr5nMoAUwZRjGtBxmz3KA1tkAj3ykkR6q2B2C"
verifyMsgSign := "5c45ff5e21c57e6ad56bac8758b79b1d9ac89fd3"
// verifyTimestamp := HttpUtils.ParseUrl("timestamp")
verifyTimestamp := "1409659589"
// verifyNonce := HttpUtils.ParseUrl("nonce")
verifyNonce := "263014780"
// verifyEchoStr := HttpUtils.ParseUrl("echoStr")
verifyEchoStr := "P9nAzCzyDtyTWESHep1vC5X9xho/qYX3Zpb4yKa9SKld1DsH3Iyt3tP3zNdtp 4RPcs8TgAE7OaBO FZXvnaqQ=="
// 创建微信客服API的封装结构体实例
wxService := NewKefuWework(corpid, corpsecret, token, encodingAeskey)
res, err := wxService.CheckSign(verifyMsgSign, verifyTimestamp, verifyNonce, verifyEchoStr)
log.Println(res, err)
}官方的sdk
代码语言：javascript复制package wechat_kf_sdk
import (
"bytes"
"crypto/aes"
"crypto/cipher"
"crypto/sha1"
"encoding/base64"
"encoding/binary"
"encoding/xml"
"fmt"
"math/rand"
"sort"
"strings"
)
const letterBytes = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
const (
ValidateSignatureError int = -40001
ParseXmlError int = -40002
ComputeSignatureError int = -40003
IllegalAesKey int = -40004
ValidateCorpidError int = -40005
EncryptAESError int = -40006
DecryptAESError int = -40007
IllegalBuffer int = -40008
EncodeBase64Error int = -40009
DecodeBase64Error int = -40010
GenXmlError int = -40010
ParseJsonError int = -40012
GenJsonError int = -40013
IllegalProtocolType int = -40014
)
type ProtocolType int
const (
XmlType ProtocolType = 1
)
type CryptError struct {
ErrCode int
ErrMsg string
}
func NewCryptError(err_code int, err_msg string) *CryptError {
return &CryptError{ErrCode: err_code, ErrMsg: err_msg}
}
type WXBizMsg4Recv struct {
Tousername string `xml:"ToUserName"`
Encrypt string `xml:"Encrypt"`
Agentid string `xml:"AgentID"`
}
type CDATA struct {
Value string `xml:",cdata"`
}
type WXBizMsg4Send struct {
XMLName xml.Name `xml:"xml"`
Encrypt CDATA `xml:"Encrypt"`
Signature CDATA `xml:"MsgSignature"`
Timestamp string `xml:"TimeStamp"`
Nonce CDATA `xml:"Nonce"`
}
func NewWXBizMsg4Send(encrypt, signature, timestamp, nonce string) *WXBizMsg4Send {
return &WXBizMsg4Send{Encrypt: CDATA{Value: encrypt}, Signature: CDATA{Value: signature}, Timestamp: timestamp, Nonce: CDATA{Value: nonce}}
}
type ProtocolProcessor interface {
parse(src_data []byte) (*WXBizMsg4Recv, *CryptError)
serialize(msg_send *WXBizMsg4Send) ([]byte, *CryptError)
}
type WXBizMsgCrypt struct {
token string
encoding_aeskey string
receiver_id string
protocol_processor ProtocolProcessor
}
type XmlProcessor struct {
}
func (self *XmlProcessor) parse(src_data []byte) (*WXBizMsg4Recv, *CryptError) {
var msg4_recv WXBizMsg4Recv
err := xml.Unmarshal(src_data, &msg4_recv)
if nil != err {
return nil, NewCryptError(ParseXmlError, "xml to msg fail")
}
return &msg4_recv, nil
}
func (self *XmlProcessor) serialize(msg4_send *WXBizMsg4Send) ([]byte, *CryptError) {
xml_msg, err := xml.Marshal(msg4_send)
if nil != err {
return nil, NewCryptError(GenXmlError, err.Error())
}
return xml_msg, nil
}
func NewWXBizMsgCrypt(token, encoding_aeskey, receiver_id string, protocol_type ProtocolType) *WXBizMsgCrypt {
var protocol_processor ProtocolProcessor
if protocol_type != XmlType {
panic("unsupport protocal")
} else {
protocol_processor = new(XmlProcessor)
}
return &WXBizMsgCrypt{token: token, encoding_aeskey: (encoding_aeskey "="), receiver_id: receiver_id, protocol_processor: protocol_processor}
}
func (self *WXBizMsgCrypt) randString(n int) string {
b := make([]byte, n)
for i := range b {
b[i] = letterBytes[rand.Int63()%int64(len(letterBytes))]
}
return string(b)
}
func (self *WXBizMsgCrypt) pKCS7Padding(plaintext string, block_size int) []byte {
padding := block_size - (len(plaintext) % block_size)
padtext := bytes.Repeat([]byte{byte(padding)}, padding)
var buffer bytes.Buffer
buffer.WriteString(plaintext)
buffer.Write(padtext)
return buffer.Bytes()
}
func (self *WXBizMsgCrypt) pKCS7Unpadding(plaintext []byte, block_size int) ([]byte, *CryptError) {
plaintext_len := len(plaintext)
if nil == plaintext || plaintext_len == 0 {
return nil, NewCryptError(DecryptAESError, "pKCS7Unpadding error nil or zero")
}
if plaintext_len%block_size != 0 {
return nil, NewCryptError(DecryptAESError, "pKCS7Unpadding text not a multiple of the block size")
}
padding_len := int(plaintext[plaintext_len-1])
return plaintext[:plaintext_len-padding_len], nil
}
func (self *WXBizMsgCrypt) cbcEncrypter(plaintext string) ([]byte, *CryptError) {
aeskey, err := base64.StdEncoding.DecodeString(self.encoding_aeskey)
if nil != err {
return nil, NewCryptError(DecodeBase64Error, err.Error())
}
const block_size = 32
pad_msg := self.pKCS7Padding(plaintext, block_size)
block, err := aes.NewCipher(aeskey)
if err != nil {
return nil, NewCryptError(EncryptAESError, err.Error())
}
ciphertext := make([]byte, len(pad_msg))
iv := aeskey[:aes.BlockSize]
mode := cipher.NewCBCEncrypter(block, iv)
mode.CryptBlocks(ciphertext, pad_msg)
base64_msg := make([]byte, base64.StdEncoding.EncodedLen(len(ciphertext)))
base64.StdEncoding.Encode(base64_msg, ciphertext)
return base64_msg, nil
}
func (self *WXBizMsgCrypt) cbcDecrypter(base64_encrypt_msg string) ([]byte, *CryptError) {
aeskey, err := base64.StdEncoding.DecodeString(self.encoding_aeskey)
if nil != err {
return nil, NewCryptError(DecodeBase64Error, err.Error())
}
encrypt_msg, err := base64.StdEncoding.DecodeString(base64_encrypt_msg)
if nil != err {
return nil, NewCryptError(DecodeBase64Error, err.Error())
}
block, err := aes.NewCipher(aeskey)
if err != nil {
return nil, NewCryptError(DecryptAESError, err.Error())
}
if len(encrypt_msg) < aes.BlockSize {
return nil, NewCryptError(DecryptAESError, "encrypt_msg size is not valid")
}
iv := aeskey[:aes.BlockSize]
if len(encrypt_msg)�s.BlockSize != 0 {
return nil, NewCryptError(DecryptAESError, "encrypt_msg not a multiple of the block size")
}
mode := cipher.NewCBCDecrypter(block, iv)
mode.CryptBlocks(encrypt_msg, encrypt_msg)
return encrypt_msg, nil
}
func (self *WXBizMsgCrypt) calSignature(timestamp, nonce, data string) string {
sort_arr := []string{self.token, timestamp, nonce, data}
sort.Strings(sort_arr)
var buffer bytes.Buffer
for _, value := range sort_arr {
buffer.WriteString(value)
}
sha := sha1.New()
sha.Write(buffer.Bytes())
signature := fmt.Sprintf("%x", sha.Sum(nil))
return string(signature)
}
func (self *WXBizMsgCrypt) ParsePlainText(plaintext []byte) ([]byte, uint32, []byte, []byte, *CryptError) {
const block_size = 32
plaintext, err := self.pKCS7Unpadding(plaintext, block_size)
if nil != err {
return nil, 0, nil, nil, err
}
text_len := uint32(len(plaintext))
if text_len < 20 {
return nil, 0, nil, nil, NewCryptError(IllegalBuffer, "plain is to small 1")
}
random := plaintext[:16]
msg_len := binary.BigEndian.Uint32(plaintext[16:20])
if text_len < (20 msg_len) {
return nil, 0, nil, nil, NewCryptError(IllegalBuffer, "plain is to small 2")
}
msg := plaintext[20 : 20 msg_len]
receiver_id := plaintext[20 msg_len:]
return random, msg_len, msg, receiver_id, nil
}
func (self *WXBizMsgCrypt) VerifyURL(msg_signature, timestamp, nonce, echostr string) ([]byte, *CryptError) {
signature := self.calSignature(timestamp, nonce, echostr)
if strings.Compare(signature, msg_signature) != 0 {
return nil, NewCryptError(ValidateSignatureError, "signature not equal")
}
plaintext, err := self.cbcDecrypter(echostr)
if nil != err {
return nil, err
}
_, _, msg, receiver_id, err := self.ParsePlainText(plaintext)
if nil != err {
return nil, err
}
if len(self.receiver_id) > 0 && strings.Compare(string(receiver_id), self.receiver_id) != 0 {
fmt.Println(string(receiver_id), self.receiver_id, len(receiver_id), len(self.receiver_id))
return nil, NewCryptError(ValidateCorpidError, "receiver_id is not equil")
}
return msg, nil
}
func (self *WXBizMsgCrypt) EncryptMsg(reply_msg, timestamp, nonce string) ([]byte, *CryptError) {
rand_str := self.randString(16)
var buffer bytes.Buffer
buffer.WriteString(rand_str)
msg_len_buf := make([]byte, 4)
binary.BigEndian.PutUint32(msg_len_buf, uint32(len(reply_msg)))
buffer.Write(msg_len_buf)
buffer.WriteString(reply_msg)
buffer.WriteString(self.receiver_id)
tmp_ciphertext, err := self.cbcEncrypter(buffer.String())
if nil != err {
return nil, err
}
ciphertext := string(tmp_ciphertext)
signature := self.calSignature(timestamp, nonce, ciphertext)
msg4_send := NewWXBizMsg4Send(ciphertext, signature, timestamp, nonce)
return self.protocol_processor.serialize(msg4_send)
}
func (self *WXBizMsgCrypt) DecryptMsg(msg_signature, timestamp, nonce string, post_data []byte) ([]byte, *CryptError) {
msg4_recv, crypt_err := self.protocol_processor.parse(post_data)
if nil != crypt_err {
return nil, crypt_err
}
signature := self.calSignature(timestamp, nonce, msg4_recv.Encrypt)
if strings.Compare(signature, msg_signature) != 0 {
return nil, NewCryptError(ValidateSignatureError, "signature not equal")
}
plaintext, crypt_err := self.cbcDecrypter(msg4_recv.Encrypt)
if nil != crypt_err {
return nil, crypt_err
}
_, _, msg, receiver_id, crypt_err := self.ParsePlainText(plaintext)
if nil != crypt_err {
return nil, crypt_err
}
if len(self.receiver_id) > 0 && strings.Compare(string(receiver_id), self.receiver_id) != 0 {
return nil, NewCryptError(ValidateCorpidError, "receiver_id is not equil")
}
return msg, nil
}测试结果成功解析出加密的echostr
go test -v kf.go kf_test.go wxbizmsgcrypt.go --run TestCheckSign === RUN TestCheckSign 1616140317555161061 <nil> --- PASS: TestCheckSign (0.01s)
放到验证接口里使用就可以了
这是验证通过的效果
