假设我正在尝试从使用基本身份验证/基本证书的 RESTful api 中提取,那么在我的程序中存储该用户名和密码的最佳方式是什么?现在它只是以纯文本形式存在。
UsernamePasswordCredentials creds = new UsernamePasswordCredentials("myName@myserver","myPassword1234");
有没有更安全的方法?
谢谢
最佳答案
重要提示:
如果您将身份验证系统作为一个整体进行设计,则不应存储密码,即使密码已加密。您存储一个哈希,并检查登录期间提供的密码是否与相同的哈希匹配。这样一来,您的数据库中的安全漏洞就可以避免暴露您的用户密码。
话虽如此,对于您要按原样存储数据(在本例中为密码)的情况,然后采用从内到外的心态,以下是保护您的流程的一些步骤:
第一步,您应该将密码处理从 String
更改为 character array
。
原因是 String
是一个 immutable
对象,因此即使对象设置为 null,它的数据也不会立即被清除
;数据被设置为垃圾收集,这会带来安全问题,因为恶意程序可能会在清理之前访问该 String
(密码)数据。
这是 Swing's JPasswordField's getText()
的主要原因方法已弃用,为什么 getPassword()
uses character arrays .
第二步是加密您的凭据,仅在身份验证过程中临时解密它们。或者在服务器端对它们进行散列,存储该散列,然后“忘记”原始密码。
这与第一步类似,可确保您的漏洞时间尽可能短。
建议您的凭据不要硬编码,而是以集中、可配置且易于维护的方式存储它们,例如配置或属性文件或数据库。
您应该在保存文件之前加密您的凭据,此外,您可以对文件本身应用第二次加密(对凭据进行 2 层加密,对其他文件内容进行 1 层加密)。
请注意,上面提到的两个加密过程中的每一个都可以是多层的。每次加密都可以是 Triple Data Encryption Standard (AKA TDES and 3DES) 的单独应用程序,作为一个概念性的例子。
在您的本地环境得到适当保护后(但请记住,它永远不会“安全”!),第三步是对您的传输过程应用基本保护,方法是使用 TLS (Transport Layer Security) or SSL (Secure Sockets Layer) .
第四步是应用其他保护方法。
例如,对您的“使用”编译应用混淆技术,以避免(即使很快)暴露您的安全措施,以防您的程序被 Ms. Eve, Mr. Mallory, or someone else (the bad-guys) 获取。并反编译。
更新 1:
应@Damien.Bell 的要求,下面是一个涵盖第一步和第二步的示例:
//These will be used as the source of the configuration file's stored attributes.
private static final Map<String, String> COMMON_ATTRIBUTES = new HashMap<String, String>();
private static final Map<String, char[]> SECURE_ATTRIBUTES = new HashMap<String, char[]>();
//Ciphering (encryption and decryption) password/key.
private static final char[] PASSWORD = "Unauthorized_Personel_Is_Unauthorized".toCharArray();
//Cipher salt.
private static final byte[] SALT = {
(byte) 0xde, (byte) 0x33, (byte) 0x10, (byte) 0x12,
(byte) 0xde, (byte) 0x33, (byte) 0x10, (byte) 0x12,};
//Desktop dir:
private static final File DESKTOP = new File(System.getProperty("user.home") + "/Desktop");
//File names:
private static final String NO_ENCRYPTION = "no_layers.txt";
private static final String SINGLE_LAYER = "single_layer.txt";
private static final String DOUBLE_LAYER = "double_layer.txt";
/**
* @param args the command line arguments
*/
public static void main(String[] args) throws GeneralSecurityException, FileNotFoundException, IOException {
//Set common attributes.
COMMON_ATTRIBUTES.put("Gender", "Male");
COMMON_ATTRIBUTES.put("Age", "21");
COMMON_ATTRIBUTES.put("Name", "Hypot Hetical");
COMMON_ATTRIBUTES.put("Nickname", "HH");
/*
* Set secure attributes.
* NOTE: Ignore the use of Strings here, it's being used for convenience only.
* In real implementations, JPasswordField.getPassword() would send the arrays directly.
*/
SECURE_ATTRIBUTES.put("Username", "Hypothetical".toCharArray());
SECURE_ATTRIBUTES.put("Password", "LetMePass_Word".toCharArray());
/*
* For demosntration purposes, I make the three encryption layer-levels I mention.
* To leave no doubt the code works, I use real file IO.
*/
//File without encryption.
create_EncryptedFile(NO_ENCRYPTION, COMMON_ATTRIBUTES, SECURE_ATTRIBUTES, 0);
//File with encryption to secure attributes only.
create_EncryptedFile(SINGLE_LAYER, COMMON_ATTRIBUTES, SECURE_ATTRIBUTES, 1);
//File completely encrypted, including re-encryption of secure attributes.
create_EncryptedFile(DOUBLE_LAYER, COMMON_ATTRIBUTES, SECURE_ATTRIBUTES, 2);
/*
* Show contents of all three encryption levels, from file.
*/
System.out.println("NO ENCRYPTION: \n" + readFile_NoDecryption(NO_ENCRYPTION) + "\n\n\n");
System.out.println("SINGLE LAYER ENCRYPTION: \n" + readFile_NoDecryption(SINGLE_LAYER) + "\n\n\n");
System.out.println("DOUBLE LAYER ENCRYPTION: \n" + readFile_NoDecryption(DOUBLE_LAYER) + "\n\n\n");
/*
* Decryption is demonstrated with the Double-Layer encryption file.
*/
//Descrypt first layer. (file content) (REMEMBER: Layers are in reverse order from writing).
String decryptedContent = readFile_ApplyDecryption(DOUBLE_LAYER);
System.out.println("READ: [first layer decrypted]\n" + decryptedContent + "\n\n\n");
//Decrypt second layer (secure data).
for (String line : decryptedContent.split("\n")) {
String[] pair = line.split(": ", 2);
if (pair[0].equalsIgnoreCase("Username") || pair[0].equalsIgnoreCase("Password")) {
System.out.println("Decrypted: " + pair[0] + ": " + decrypt(pair[1]));
}
}
}
private static String encrypt(byte[] property) throws GeneralSecurityException {
SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("PBEWithMD5AndDES");
SecretKey key = keyFactory.generateSecret(new PBEKeySpec(PASSWORD));
Cipher pbeCipher = Cipher.getInstance("PBEWithMD5AndDES");
pbeCipher.init(Cipher.ENCRYPT_MODE, key, new PBEParameterSpec(SALT, 20));
//Encrypt and save to temporary storage.
String encrypted = Base64.encodeBytes(pbeCipher.doFinal(property));
//Cleanup data-sources - Leave no traces behind.
for (int i = 0; i < property.length; i++) {
property[i] = 0;
}
property = null;
System.gc();
//Return encryption result.
return encrypted;
}
private static String encrypt(char[] property) throws GeneralSecurityException {
//Prepare and encrypt.
byte[] bytes = new byte[property.length];
for (int i = 0; i < property.length; i++) {
bytes[i] = (byte) property[i];
}
String encrypted = encrypt(bytes);
/*
* Cleanup property here. (child data-source 'bytes' is cleaned inside 'encrypt(byte[])').
* It's not being done because the sources are being used multiple times for the different layer samples.
*/
// for (int i = 0; i < property.length; i++) { //cleanup allocated data.
// property[i] = 0;
// }
// property = null; //de-allocate data (set for GC).
// System.gc(); //Attempt triggering garbage-collection.
return encrypted;
}
private static String encrypt(String property) throws GeneralSecurityException {
String encrypted = encrypt(property.getBytes());
/*
* Strings can't really have their allocated data cleaned before CG,
* that's why secure data should be handled with char[] or byte[].
* Still, don't forget to set for GC, even for data of sesser importancy;
* You are making everything safer still, and freeing up memory as bonus.
*/
property = null;
return encrypted;
}
private static String decrypt(String property) throws GeneralSecurityException, IOException {
SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("PBEWithMD5AndDES");
SecretKey key = keyFactory.generateSecret(new PBEKeySpec(PASSWORD));
Cipher pbeCipher = Cipher.getInstance("PBEWithMD5AndDES");
pbeCipher.init(Cipher.DECRYPT_MODE, key, new PBEParameterSpec(SALT, 20));
return new String(pbeCipher.doFinal(Base64.decode(property)));
}
private static void create_EncryptedFile(
String fileName,
Map<String, String> commonAttributes,
Map<String, char[]> secureAttributes,
int layers)
throws GeneralSecurityException, FileNotFoundException, IOException {
StringBuilder sb = new StringBuilder();
for (String k : commonAttributes.keySet()) {
sb.append(k).append(": ").append(commonAttributes.get(k)).append(System.lineSeparator());
}
//First encryption layer. Encrypts secure attribute values only.
for (String k : secureAttributes.keySet()) {
String encryptedValue;
if (layers >= 1) {
encryptedValue = encrypt(secureAttributes.get(k));
} else {
encryptedValue = new String(secureAttributes.get(k));
}
sb.append(k).append(": ").append(encryptedValue).append(System.lineSeparator());
}
//Prepare file and file-writing process.
File f = new File(DESKTOP, fileName);
if (!f.getParentFile().exists()) {
f.getParentFile().mkdirs();
} else if (f.exists()) {
f.delete();
}
BufferedWriter bw = new BufferedWriter(new FileWriter(f));
//Second encryption layer. Encrypts whole file content including previously encrypted stuff.
if (layers >= 2) {
bw.append(encrypt(sb.toString().trim()));
} else {
bw.append(sb.toString().trim());
}
bw.flush();
bw.close();
}
private static String readFile_NoDecryption(String fileName) throws FileNotFoundException, IOException, GeneralSecurityException {
File f = new File(DESKTOP, fileName);
BufferedReader br = new BufferedReader(new FileReader(f));
StringBuilder sb = new StringBuilder();
while (br.ready()) {
sb.append(br.readLine()).append(System.lineSeparator());
}
return sb.toString();
}
private static String readFile_ApplyDecryption(String fileName) throws FileNotFoundException, IOException, GeneralSecurityException {
File f = new File(DESKTOP, fileName);
BufferedReader br = new BufferedReader(new FileReader(f));
StringBuilder sb = new StringBuilder();
while (br.ready()) {
sb.append(br.readLine()).append(System.lineSeparator());
}
return decrypt(sb.toString());
}
解决每个保护步骤的完整示例将远远超出我认为对这个问题的合理性,因为它是关于“步骤是什么”,而不是“如何应用它们".
这将远远超过我的答案(最后是抽样),而 S.O.已经针对这些步骤的“如何做”进行了说明,更加合适,并为每个单独步骤的实现提供了更好的解释和示例。
关于java - 处理源代码中用于身份验证的密码,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/12937641/