加密和解密iOS / Node.js安全查询

时间:2015-10-13 00:25:09

标签: ios node.js encryption sha256 password-encryption

我目前在两个平台上使用AES128,而我的代码来自answer
注意:我改变了一些代码以避免使用IV,因为我觉得这对于我的应用程序来说太过分了。

的node.js:

    var CryptoJS = require("crypto-js");
    var crypto = require('crypto');
    var password = "1234567890123456";
    var salt = "gettingsaltyfoo!";
    var hash = CryptoJS.SHA256(salt);
    var key = CryptoJS.PBKDF2(password, hash, { keySize: 256/32, iterations: 1000 });
    var algorithm = 'aes128';
    console.log(key.toString(CryptoJS.enc.Base64));

function encrypt(text){
  var cipher = crypto.createCipher(algorithm,key.toString(CryptoJS.enc.Base64));
  var crypted = cipher.update(text,'utf8','hex');
  crypted += cipher.final('hex');
  return crypted;
}

function decrypt(text){
  var decipher = crypto.createDecipher(algorithm,key.toString(CryptoJS.enc.Base64));
  var dec = decipher.update(text,'hex','utf8');
  dec += decipher.final('utf8');
  return dec;
}


iOS的:

        #import <CommonCrypto/CommonCrypto.h>
NSString* password = @"1234567890123456";
NSString* salt = @"gettingsaltyfoo!";
-(NSString *)decrypt:(NSString*)encrypted64{

    NSMutableData* hash = [NSMutableData dataWithLength:CC_SHA256_DIGEST_LENGTH];
    NSMutableData* key = [NSMutableData dataWithLength:CC_SHA256_DIGEST_LENGTH];
    CC_SHA256(salt.UTF8String, (CC_LONG)strlen(salt.UTF8String), hash.mutableBytes);
    CCKeyDerivationPBKDF(kCCPBKDF2, password.UTF8String, strlen(password.UTF8String), hash.bytes, hash.length, kCCPRFHmacAlgSHA1, 1000, key.mutableBytes, key.length);
    NSLog(@"Hash : %@",[hash base64EncodedStringWithOptions:0]);
    NSLog(@"Key : %@",[key base64EncodedStringWithOptions:0]);


    NSData* encryptedWithout64 = [[NSData alloc] initWithBase64EncodedString:encrypted64 options:0];
    NSMutableData* decrypted = [NSMutableData dataWithLength:encryptedWithout64.length + kCCBlockSizeAES128];
    size_t bytesDecrypted = 0;
    CCCrypt(kCCDecrypt,
            kCCAlgorithmAES128,
            kCCOptionPKCS7Padding,
            key.bytes,
            key.length,
            NULL,
            encryptedWithout64.bytes, encryptedWithout64.length,
            decrypted.mutableBytes, decrypted.length, &bytesDecrypted);
    NSData* outputMessage = [NSMutableData dataWithBytes:decrypted.mutableBytes length:bytesDecrypted];
    NSString* outputString = [[NSString alloc] initWithData:outputMessage encoding:NSUTF8StringEncoding];
    NSLog(@"Decrypted : %@",outputString);


    return outputString;
}
-(NSString *)encrypt:(NSString *)toEncrypt{
    NSMutableData* hash = [NSMutableData dataWithLength:CC_SHA256_DIGEST_LENGTH];
    NSMutableData* key = [NSMutableData dataWithLength:CC_SHA256_DIGEST_LENGTH];
    CC_SHA256(salt.UTF8String, (CC_LONG)strlen(salt.UTF8String), hash.mutableBytes);
    CCKeyDerivationPBKDF(kCCPBKDF2, password.UTF8String, strlen(password.UTF8String), hash.bytes, hash.length, kCCPRFHmacAlgSHA1, 1000, key.mutableBytes, key.length);

    NSData* message = [toEncrypt dataUsingEncoding:NSUTF8StringEncoding];
    NSMutableData* encrypted = [NSMutableData dataWithLength:message.length + kCCBlockSizeAES128];
    size_t bytesEncrypted = 0;
    CCCrypt(kCCEncrypt,
            kCCAlgorithmAES128,
            kCCOptionPKCS7Padding,
            key.bytes,
            key.length,
            NULL,
            message.bytes, message.length,
            encrypted.mutableBytes, encrypted.length, &bytesEncrypted);
    NSString* encrypted64 = [[NSMutableData dataWithBytes:encrypted.mutableBytes length:bytesEncrypted] base64EncodedStringWithOptions:0];
    NSLog(@"Encrypted : %@",encrypted64);
    return encrypted64;
}

我的问题:如果我像这样对盐进行硬编码可以吗?我试图加密和解密密码(var密码和NSString密码可能会被硬编码成某种东西)。我在网上看到我需要在我的数据库中保存我的密码。如果我硬编码我的盐是不行的,我如何将它从iOS发送到node.js并与盐一致?我的iOS请求应该是这样的吗?

{
key:"someKeyGeneratedOnTheSpotWithRandomSalt",
password:"somePasswordGeneratedFromKey"
}

并在我的后端通过从数据库中提取这些字段来检查密码?

{
key:"someKeyGeneratedWhenTheUserFirstSignedUp",
password:"somePasswordGeneratedFromTheOrginalKeyWhenUserFirstSignedUp"
}

然后使用从两种方案生成的密钥和密码解密两个密码?

OR是否可以使用硬编码的盐,比如说用户名,这样每个用户的密钥总是一样的?

基本上我对我是否对我的加密模型有正确的想法感到困惑。

感谢您的帮助。

1 个答案:

答案 0 :(得分:1)

通常使用随机盐并将其添加到加密数据之前。所有前缀PBKDF2迭代计数以及版本号都有助于未来验证。最后,跳过iv会减少对第一个块的保护,您可能会考虑使用身份验证哈希。

这类似于RNCryptor所做的。有关加密邮件的详细信息,请参阅RNCryptor-Spec-v3.md

注意:
我不理解盐的CC_SHA256,这是不必要的。

NSData* outputMessage = [NSMutableData dataWithBytes:decrypted.mutableBytes length:bytesDecrypted];
是不必要的,只需设置decrypted的长度 decrypted.length = bytesDecrypted;
并使用decrypted代替outputMessage