修复对gcm算法的支持

Readme.md

@@ -173,7 +173,7 @@ crypto.hmac('md5', '123456', 'sdfvkjfhd')
 > 在上面的2种算法中，加密都是不可逆的，也就是说，加密后的字符，我们是没办法再还原回去了，但是有很多场景，需要我们对拿到的加密字符，还原到明文状态。
 > 所以出现了公钥加密这种算法; 而`Node.js`本身给我们提供了4种与公钥加密相关的类：`Cipher/Decipher、Sign、Verify`，这里只讲前面2个，以及它们衍生出来的`Cipheriv/Decipheriv`;
 
-#### cipher(mode, data[, key][, inEncode][, outEncode])
+#### cipher(mode, data[, key, inEncode, outEncode])
 - mode `<String>`
 - data `<String>` | `<Buffer>`
 - key `<String>` 可选
@@ -182,24 +182,32 @@ crypto.hmac('md5', '123456', 'sdfvkjfhd')
 
 > `mode`为算法类型，常见的有`aes-128-cbc、aes-128-gcm`等等地，很多，具体有哪些可以通过 `this.crypto.getCiphers()` 来查看。
 > 其他的参数与上面的HMAC算法相似; `inEncode`即声明要加密的数据是什么编码的，默认根据要加密的数据进行判断。
+>> 需要注意的是, 算法类型为`aes-***-gcm`时, 返回的不是一个字符串, 而是一个对象{ enStr, authTag }, 解密时, 需要提供这个 authTag方可解密
 
 ```javascript
 // 这里给出一个AES-128-CBC的加密例子
-// 
+
 crypto.cipher('aes-128-cbc', '123456', 'abcdefg')
 // mqA9ZPh9VV+fwKlfpicGVg==
 
 crypto.cipher('aes-128-cbc', '123456', 'abcdefg', 'utf8', 'hex')
 // 9aa03d64f87d555f9fc0a95fa6270656
 
+// 要注意gcm算法的结果
+crypto.cipher('aes-128-gcm', '123456', 'abcdefg')
+// { enStr: 'qmo1a4Jz',
+//   authTag: <Buffer c4 a0 3e ab e5 34 a0 ea 25 02 f0 91 06 f7 3b dd> 
+// }
+
 ```
 
 
 
-#### decipher(mode, data[, key][, inEncode][, outEncode])
+#### decipher(mode, data[, key, tag, inEncode, outEncode])
 - mode `<String>`
 - data `<String>` | `<Buffer>`
 - key `<String>` 可选
+- tag `<Buffer>` 可选(mode为gcm算法时必填)
 - inEncode '<String>' 可选, 默认是base64
 - outEncode '<String>' 可选，默认utf8
 
@@ -214,7 +222,16 @@ crypto.decipher('aes-128-cbc', 'mqA9ZPh9VV+fwKlfpicGVg==', 'abcdefg')
 crypto.decipher('aes-128-cbc', '9aa03d64f87d555f9fc0a95fa6270656', 'abcdefg', 'hex')
 // 123456
 
+
+
+// 要注意gcm算法的结果
+// authTag: <Buffer c4 a0 3e ab e5 34 a0 ea 25 02 f0 91 06 f7 3b dd> 
+crypto.decipher('aes-128-gcm', 'qmo1a4Jz', 'abcdefg', authTag)
+// 123456
+
+
 ```
 
 
-> 至于另外的`cipheriv/decipheriv`这2个方法，这里就不细讲了，和上面的这2个是同样的用法，只是要多1个参数`向量(iv)`, **`特别要注意的一点是，选择128位的加密算法，那key的长度就必须是16位，256则是32位，依此类推; 向量iv是16位`，具体的请看相关文档**
+> 至于另外的`cipheriv/decipheriv`这2个方法，这里就不细讲了，和上面的这2个是同样的用法，只是要多1个参数`向量(iv)`
+>> **`特别要注意的一点是，选择128位的加密算法，那key的长度就必须是16位，256则是32位，依此类推; 算法类型为gcm时,返回的是对象,解密时需要提供authTag `，具体的请看相关文档**

index.js

@@ -8,6 +8,7 @@
 
 const CRYPTO = require('crypto')
 const FS = require('fs')
+const GCM_MODE = ['aes-128-gcm', 'aes-192-gcm', 'aes-256-gcm']
 
 module.exports = {
   origin: CRYPTO,
@@ -37,20 +38,29 @@ module.exports = {
     inEncode = isBuffer ? 'binary' : inEncode || 'utf8'
     outEncode = outEncode || 'base64'
 
-    let cp = CRYPTO.createCipher(mode, key)
-    let res = cp.update(data, inEncode, outEncode)
-    return res + cp.final(outEncode)
+    let cc = CRYPTO.createCipher(mode, key)
+    let enStr = cc.update(data, inEncode, outEncode)
+    enStr += cc.final(outEncode)
+    if (GCM_MODE.indexOf(mode) > -1) {
+      let authTag = cc.getAuthTag()
+      return { enStr: enStr, authTag: authTag }
+    }
+    return enStr
   },
 
-  decipher(mode, data, key, inEncode, outEncode) {
+  decipher(mode, data, key, tag, inEncode, outEncode) {
     key = key || ''
     let isBuffer = Buffer.isBuffer(data)
     inEncode = isBuffer ? 'binary' : inEncode || 'base64'
     outEncode = outEncode || 'utf8'
 
-    let dcp = CRYPTO.createDecipher(mode, key)
-    let res = dcp.update(data, inEncode, outEncode)
-    return res + dcp.final(outEncode)
+    let cd = CRYPTO.createDecipher(mode, key)
+    if (GCM_MODE.indexOf(mode) > -1) {
+      cd.setAuthTag(tag)
+    }
+    let deStr = cd.update(data, inEncode, outEncode)
+    deStr += cd.final(outEncode)
+    return deStr
   },
 
   cipheriv(mode, data, key, iv, inEncode, outEncode) {
@@ -60,21 +70,30 @@ module.exports = {
     inEncode = isBuffer ? 'binary' : inEncode || 'utf8'
     outEncode = outEncode || 'base64'
 
-    let cp = CRYPTO.createCipheriv(mode, key, iv)
-    let res = cp.update(data, inEncode, outEncode)
-    return res + cp.final(outEncode)
+    let cciv = CRYPTO.createCipheriv(mode, key, iv)
+    let enStr = cciv.update(data, inEncode, outEncode)
+    enStr += cciv.final(outEncode)
+    if (GCM_MODE.indexOf(mode) > -1) {
+      let authTag = cciv.getAuthTag()
+      return { enStr: enStr, authTag: authTag }
+    }
+    return enStr
   },
 
-  decipheriv(mode, data, key, iv, inEncode, outEncode) {
+  decipheriv(mode, data, key, iv, tag, inEncode, outEncode) {
     key = key || '0000000000000000'
     iv = iv || ''
     let isBuffer = Buffer.isBuffer(data)
     inEncode = isBuffer ? 'binary' : inEncode || 'base64'
     outEncode = outEncode || 'utf8'
 
-    let dcp = CRYPTO.createDecipheriv(mode, key, iv)
-    let res = dcp.update(data, inEncode, outEncode)
-    return res + dcp.final(outEncode)
+    let dcpiv = CRYPTO.createDecipheriv(mode, key, iv)
+    if (GCM_MODE.indexOf(mode) > -1) {
+      dcpiv.setAuthTag(tag)
+    }
+    let deStr = dcpiv.update(data, inEncode, outEncode)
+    deStr += dcpiv.final(outEncode)
+    return deStr
   },
 
   /**

package.json

@@ -1,6 +1,6 @@
 {
   "name": "crypto.js",
-  "version": "1.1.6",
+  "version": "1.2.0",
   "description": "原生crypto加密模块的二次封装,简化常用加密函数的使用",
   "keywords": ["md5", "sha1", "base64", "fivejs", "crypto"],
   "author": "yutent <yutent@doui.cc>",