Add SHA1, CryptMsg methods.

README.md

@@ -1,3 +1,5 @@
 # Wechat AES
 
   提供接收和推送给微信公众平台消息的加解密接口
+
+  参见微信开放平台->第三方平台->[消息加解密接入指引](https://open.weixin.qq.com/cgi-bin/showdocument?action=dir_list&t=resource/res_list&verify=1&id=open1419318479&token=&lang=zh_CN)

crypt.go

@@ -4,6 +4,8 @@ import (
     "crypto/aes"
     "crypto/cipher"
     "encoding/base64"
+    "encoding/xml"
+    "fmt"
     mathRand "math/rand"
     "time"
 )
@@ -40,6 +42,51 @@ func WechatCryptorRandomStr() string {
     return string(result)
 }
 
+const WechatCryptorEncryptMsgFormat = `
+<xml>
+<Encrypt><![CDATA[%s]]></Encrypt>
+<MsgSignature><![CDATA[%s]]></MsgSignature>
+<TimeStamp>%s</TimeStamp>
+<Nonce><![CDATA[%s]]></Nonce>
+</xml>
+`
+
+func (cryptor *WechatCryptor) EncryptMsg(msg, timeStamp, nonce string) (string, error) {
+    encrypt, err := cryptor.Encrypt(WechatCryptorRandomStr(), msg)
+    if nil != err {
+        return "", err
+    }
+
+    if 0 == len(timeStamp) {
+        timeStamp = string(time.Now().Unix())
+    }
+
+    sign := SHA1(cryptor.token, timeStamp, nonce, encrypt)
+    return fmt.Sprintf(WechatCryptorEncryptMsgFormat, encrypt, sign, timeStamp, nonce), nil
+}
+
+type WechatCryptorPostBody struct {
+    XMLName    xml.Name `xml:"xml"`
+    ToUserName string   `xml:"ToUserName"`
+    AppId      string   `xml:"AppId"`
+    Encrypt    string   `xml:"Encrypt"`
+}
+
+func (cryptor *WechatCryptor) DecryptMsg(msgSign, timeStamp, nonce, postData string) (string, error) {
+    postBody := WechatCryptorPostBody{}
+    err := xml.Unmarshal([]byte(postData), &postBody)
+    if nil != err || 0 == len(postBody.Encrypt) {
+        return "", &WechatCryptorError{Code: ParseXmlError}
+    }
+
+    sign := SHA1(cryptor.token, timeStamp, nonce, postBody.Encrypt)
+    if msgSign != sign {
+        return "", &WechatCryptorError{Code: ValidateSignatureError}
+    }
+
+    return cryptor.Decrypt(postBody.Encrypt)
+}
+
 // 对明文进行加密
 func (cryptor *WechatCryptor) Encrypt(randomStr, text string) (string, error) {
     randomBytes := []byte(randomStr)

crypt_test.go

@@ -1,6 +1,7 @@
 package wechataes
 
 import (
+    "encoding/xml"
     "fmt"
     "testing"
 )
@@ -11,30 +12,49 @@ var encodingAesKey = "abcdefghijklmnopqrstuvwxyz0123456789ABCDEFG"
 var randomStr = "aaaabbbbccccdddd"
 var replyMsg = "我是中文abcd123"
 var afterAesEncrypt = "jn1L23DB+6ELqJ+6bruv21Y6MD7KeIfP82D6gU39rmkgczbWwt5+3bnyg5K55bgVtVzd832WzZGMhkP72vVOfg=="
-var replyMsg2 = "<xml><ToUserName><![CDATA[oia2Tj我是中文jewbmiOUlr6X-1crbLOvLw]]></ToUserName><FromUserName><![CDATA[gh_7f083739789a]]></FromUserName><CreateTime>1407743423</CreateTime><MsgType><![CDATA[video]]></MsgType><Video><MediaId><![CDATA[eYJ1MbwPRJtOvIEabaxHs7TX2D-HV71s79GUxqdUkjm6Gs2Ed1KF3ulAOA9H1xG0]]></MediaId><Title><![CDATA[testCallBackReplyVideo]]></Title><Description><![CDATA[testCallBackReplyVideo]]></Description></Video></xml>";
+var replyMsg2 = "<xml><ToUserName><![CDATA[oia2Tj我是中文jewbmiOUlr6X-1crbLOvLw]]></ToUserName><FromUserName><![CDATA[gh_7f083739789a]]></FromUserName><CreateTime>1407743423</CreateTime><MsgType><![CDATA[video]]></MsgType><Video><MediaId><![CDATA[eYJ1MbwPRJtOvIEabaxHs7TX2D-HV71s79GUxqdUkjm6Gs2Ed1KF3ulAOA9H1xG0]]></MediaId><Title><![CDATA[testCallBackReplyVideo]]></Title><Description><![CDATA[testCallBackReplyVideo]]></Description></Video></xml>"
 var afterAesEncrypt2 = "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"
+var timestamp = "1409304348"
+var nonce = "xxxxxx"
 
-func TestNewWechatCryptor(t *testing.T) {
+func TestWechatCrypt(t *testing.T) {
     cryptor, _ := NewWechatCryptor(appId, token, encodingAesKey)
     encrypt, _ := cryptor.Encrypt(randomStr, replyMsg)
-    fmt.Println(encrypt)
     if afterAesEncrypt != encrypt {
         t.Error("no异常")
     }
     decrypt, _ := cryptor.Decrypt(afterAesEncrypt)
-    fmt.Println(decrypt)
     if replyMsg != decrypt {
         t.Error("no异常")
     }
 
     encrypt2, _ := cryptor.Encrypt(randomStr, replyMsg2)
-    fmt.Println(encrypt2)
     if afterAesEncrypt2 != encrypt2 {
         t.Error("no异常")
     }
     decrypt2, _ := cryptor.Decrypt(afterAesEncrypt2)
-    fmt.Println(decrypt2)
     if replyMsg2 != decrypt2 {
         t.Error("no异常")
     }
 }
+
+type TestEncryptMsg struct {
+    XMLName      xml.Name `xml:"xml"`
+    Encrypt      string   `xml:"Encrypt"`
+    MsgSignature string   `xml:"MsgSignature"`
+}
+
+func TestWechatCryptMsg(t *testing.T) {
+    cryptor, _ := NewWechatCryptor(appId, token, encodingAesKey)
+    afterEncrpt, _ := cryptor.EncryptMsg(replyMsg, timestamp, nonce)
+
+    encryptMsg := TestEncryptMsg{}
+    xml.Unmarshal([]byte(afterEncrpt), &encryptMsg)
+    format := "<xml><ToUserName><![CDATA[toUser]]></ToUserName><Encrypt><![CDATA[%s]]></Encrypt></xml>"
+    fromXML := fmt.Sprintf(format, encryptMsg.Encrypt)
+
+    afterDecrpt, _ := cryptor.DecryptMsg(encryptMsg.MsgSignature, timestamp, nonce, fromXML)
+    if replyMsg != afterDecrpt {
+        t.Error("no异常")
+    }
+}

sign.go

@@ -0,0 +1,21 @@
+package wechataes
+
+import (
+    "crypto/sha1"
+    "encoding/hex"
+    "sort"
+    "strings"
+)
+
+func SHA1(token, timestamp, nonce, encrypt string) string {
+    array := []string{token, timestamp, nonce, encrypt}
+    sort.Strings(array)
+    str := strings.Join(array, "")
+
+    hash := sha1.New()
+    hash.Write([]byte(str))
+    sum := hash.Sum(nil)
+    sumHex := make([]byte, hex.EncodedLen(len(sum)))
+    hex.Encode(sumHex, sum)
+    return string(sumHex)
+}

sign_test.go

@@ -0,0 +1,14 @@
+package wechataes
+
+import (
+    "testing"
+)
+
+var expectSHA1 = "82c962d39941aa48552f90ef55aa323dc620cc10"
+
+func TestSHA1(t *testing.T) {
+    sha1 := SHA1(token, timestamp, nonce, afterAesEncrypt)
+    if expectSHA1 != sha1 {
+        t.Error("no异常")
+    }
+}