handle utf8 encoded string from ldap (#66)

* handle utf8 encoded string from ldap

* add utf8 group to ldap testing container

.devcontainer/docker-compose.yml

@@ -18,3 +18,4 @@ services:
       - LDAP_ADMIN_PASSWORD=password
       - LDAP_USERS=gauss,einstein
       - LDAP_PASSWORDS=password,password
+      - LDAP_GROUP=科学A部

docker-compose.yml

@@ -10,3 +10,4 @@ services:
       - LDAP_ADMIN_PASSWORD=password
       - LDAP_USERS=gauss,einstein
       - LDAP_PASSWORDS=password,password
+      - LDAP_GROUP=科学A部

index.js

@@ -1,6 +1,46 @@
 const assert = require('assert')
 const ldap = require('ldapjs')
 
+// convert an escaped utf8 string returned from ldapjs
+function _isHex(c) {
+  return (
+    (c >= '0' && c <= '9') || (c >= 'a' && c <= 'f') || (c >= 'A' && c <= 'F')
+  )
+}
+function _parseEscapedHexToUtf8(s) {
+  // convert 'cn=\\e7\\a0\\94\\e5\\8f\\91A\\e9\\83\\a8,ou=users,dc=example,dc=com'
+  // to 'cn=研发A部,ou=users,dc=example,dc=com'
+  let ret = Buffer.alloc(0)
+  let len = s.length
+  for (let i = 0; i < len; i++) {
+    let c = s[i]
+    let item
+    if (c == '\\' && i < len - 2 && _isHex(s[i + 1]) && _isHex(s[i + 2])) {
+      item = Buffer.from(s.substring(i + 1, i + 3), 'hex')
+      i += 2
+    } else {
+      item = Buffer.from(c)
+    }
+    ret = Buffer.concat([ret, item])
+  }
+  return ret.toString()
+}
+
+function _recursiveParseHexString(obj) {
+  if (Array.isArray(obj)) {
+    return obj.map((ele) => _recursiveParseHexString(ele))
+  }
+  if (typeof obj == 'string') {
+    return _parseEscapedHexToUtf8(obj)
+  }
+  if (typeof obj == 'object') {
+    for (let key in obj) {
+      obj[key] = _recursiveParseHexString(obj[key])
+    }
+    return obj
+  }
+  return obj
+}
 // convert a SearchResultEntry object in ldapjs 3.0
 // to a user object to maintain backward compatibility
 
@@ -11,7 +51,7 @@ function _searchResultToUser(pojo) {
     user[attribute.type] =
       attribute.values.length == 1 ? attribute.values[0] : attribute.values
   })
-  return user
+  return _recursiveParseHexString(user)
 }
 // bind and return the ldap client
 function _ldapBind(dn, password, starttls, ldapOpts) {
@@ -142,7 +182,7 @@ async function _searchUserGroups(
           return
         }
         res.on('searchEntry', function (entry) {
-          groups.push(entry.pojo)
+          groups.push(_recursiveParseHexString(entry.pojo))
         })
         res.on('searchReference', function (referral) {})
         res.on('error', function (err) {
@@ -422,3 +462,9 @@ class LdapAuthenticationError extends Error {
 
 module.exports.authenticate = authenticate
 module.exports.LdapAuthenticationError = LdapAuthenticationError
+
+module.exports.exportForTesting = {
+  _isHex,
+  _parseEscapedHexToUtf8,
+  _recursiveParseHexString,
+}

package.json

@@ -1,6 +1,6 @@
 {
   "name": "ldap-authentication",
-  "version": "3.2.1",
+  "version": "3.2.2",
   "description": "A simple async nodejs library for LDAP user authentication",
   "main": "index.js",
   "types": "./index.d.ts",

test/string.spec.js

@@ -0,0 +1,43 @@
+const { exportForTesting } = require('../index.js')
+const { _isHex, _parseEscapedHexToUtf8, _recursiveParseHexString } =
+  exportForTesting
+
+describe('string conversion test', () => {
+  it('unescape string test', () => {
+    let s =
+      'cn=\\e7\\a0\\94\\e5\\8f\\91A\\e9\\83\\a8,ou=users,dc=example,dc=com'
+    let us = _parseEscapedHexToUtf8(s)
+    expect(us).toEqual('cn=研发A部,ou=users,dc=example,dc=com')
+  })
+  it('unescape string test2', () => {
+    let s =
+      'cn=\\e7\\a0\\94\\e5\\8f\\91A\\e9\\83\\a8\\c2\\a9,ou=users,dc=example,dc=com'
+    let us = _parseEscapedHexToUtf8(s)
+    expect(us).toEqual('cn=研发A部©,ou=users,dc=example,dc=com')
+  })
+  it('unescape string test3', () => {
+    let s = 'cn=ABC,ou=users,dc=example,dc=com'
+    let us = _parseEscapedHexToUtf8(s)
+    expect(us).toEqual('cn=ABC,ou=users,dc=example,dc=com')
+  })
+  it('convert obj', () => {
+    let target = {
+      a: ['研发A部©', 'abc'],
+      b: 'xyz',
+      c: true,
+      d: null,
+      e: '研发A部©',
+      f: 1000,
+    }
+    let obj = {
+      a: ['\\e7\\a0\\94\\e5\\8f\\91A\\e9\\83\\a8\\c2\\a9', 'abc'],
+      b: 'xyz',
+      c: true,
+      d: null,
+      e: '\\e7\\a0\\94\\e5\\8f\\91A\\e9\\83\\a8\\c2\\a9',
+      f: 1000,
+    }
+    let converted = _recursiveParseHexString(obj)
+    expect(converted).toEqual(target)
+  })
+})

test/test.spec.js

@@ -124,6 +124,9 @@ describe('ldap-authentication test', () => {
     let user = await authenticate(options)
     expect(user).toBeTruthy()
     expect(user.groups.length).toBeGreaterThan(0)
+    expect(user.groups[0].objectName).toEqual(
+      'cn=科学A部,ou=users,dc=example,dc=com'
+    )
   })
   it('Use regular user to authenticate and fetch user group information', async () => {
     let options = {
@@ -144,6 +147,9 @@ describe('ldap-authentication test', () => {
     let user = await authenticate(options)
     expect(user).toBeTruthy()
     expect(user.groups.length).toBeGreaterThan(0)
+    expect(user.groups[0].objectName).toEqual(
+      'cn=科学A部,ou=users,dc=example,dc=com'
+    )
   })
   it('Not specifying groupMemberAttribute or groupMemberUserAttribute should not cause an error and fallback to default values', async () => {
     let options = {