本文翻译自: encrypt | Dart Package (flutter-io.cn)

译时版本： 5.0.1

encrypt

两种加密方式基于 PointyCastle 的高级 API 集合。

在查找密码哈希加密？请访问 password.

安全随机

可以生成加密的安全随机 Key 和 IV 用于工程。

切换到该库：

pub global activate encrypt

然后使用 secure-random CLI：

$ secure-random
CBoaDQIQAgceGg8dFAkMDBEOECEZCxgMBiAUFQwKFhg=

可以设定长度和 Base 输出。

$ secure-random --help
-l, --length       The length of the bytes
                   (defaults to "32")

-b, --base         Bytes represented as base 64 or base 16 (Hexdecimal)
                   (defaults to "64")

-h, --[no-]help    Show this help message

译：

$ secure-random --help
-l, --length       字节长度（默认是 32 ）

-b, --base         字节表示为 Base64 或 Base16 （16进制）（默认是 64）

-h, --[no-]help    表示帮助信息

算法

现在的状态是：

AES 带 PKCS7 填充
RSA 带 PKCS1 和 OAEP 编码
Salsa20

签名

SHA256 with RSA

用法

对称加密

AES

import 'package:encrypt/encrypt.dart';

void main() {
  final plainText = 'Lorem ipsum dolor sit amet, consectetur adipiscing elit';
  final key = Key.fromUtf8('my 32 length key................');
  final iv = IV.fromLength(16);

  final encrypter = Encrypter(AES(key));

  final encrypted = encrypter.encrypt(plainText, iv: iv);
  final decrypted = encrypter.decrypt(encrypted, iv: iv);

  print(decrypted); // Lorem ipsum dolor sit amet, consectetur adipiscing elit
  print(encrypted.base64); // R4PxiU3h8YoIRqVowBXm36ZcCeNeZ4s1OvVBTfFlZRdmohQqOpPQqD1YecJeZMAop/hZ4OxqgC1WtwvX/hP9mw==
}

操作模式

默认模式是 SIC AESMode.sic ，可以使用 mode 参数覆写：

final encrypter = Encrypter(AES(key, mode: AESMode.cbc));

支持的模式：

CBC AESMode.cbc
CFB-64 AESMode.cfb64
CTR AESMode.ctr
ECB AESMode.ecb
OFB-64/GCTR AESMode.ofb64Gctr
OFB-64 AESMode.ofb64
SIC AESMode.sic

无填充/零填充

要移除填充，需要给构造函数的 padding 参数传递 null ：

final encrypter = Encrypter(AES(key, mode: AESMode.cbc, padding: null));

Salsa20

import 'package:encrypt/encrypt.dart';

void main() {
  final plainText = 'Lorem ipsum dolor sit amet, consectetur adipiscing elit';
  final key = Key.fromLength(32);
  final iv = IV.fromLength(8);
  final encrypter = Encrypter(Salsa20(key));

  final encrypted = encrypter.encrypt(plainText, iv: iv);
  final decrypted = encrypter.decrypt(encrypted, iv: iv);

  print(decrypted); // Lorem ipsum dolor sit amet, consectetur adipiscing elit
  print(encrypted.base64); // CR+IAWBEx3sA/dLkkFM/orYr9KftrGa7lIFSAAmVPbKIOLDOzGwEi9ohstDBqDLIaXMEeulwXQ==
}

Fernet

import 'package:encrypt/encrypt.dart';
import 'dart:convert';

void main() {
  final plainText = 'Lorem ipsum dolor sit amet, consectetur adipiscing elit';
  final key = Key.fromUtf8('my32lengthsupersecretnooneknows1');
  final iv = IV.fromLength(16);

  final b64key = Key.fromUtf8(base64Url.encode(key.bytes));
  // if you need to use the ttl feature, you'll need to use APIs in the algorithm itself
  final fernet = Fernet(b64key);
  final encrypter = Encrypter(fernet);

  final encrypted = encrypter.encrypt(plainText);
  final decrypted = encrypter.decrypt(encrypted);

  print(decrypted); // Lorem ipsum dolor sit amet, consectetur adipiscing elit
  print(encrypted.base64); // random cipher text
  print(fernet.extractTimestamp(encrypted.bytes)); // unix timestamp
}

非对称加密

RSA

import 'dart:io';
import 'package:encrypt/encrypt.dart';
import 'package:pointycastle/asymmetric/api.dart';

void main() {
  final publicKey = await parseKeyFromFile<RSAPublicKey>('test/public.pem');
  final privKey = await parseKeyFromFile<RSAPrivateKey>('test/private.pem');

  final plainText = 'Lorem ipsum dolor sit amet, consectetur adipiscing elit';
  final encrypter = Encrypter(RSA(publicKey: publicKey, privateKey: privKey));

  final encrypted = encrypter.encrypt(plainText);
  final decrypted = encrypter.decrypt(encrypted);

  print(decrypted); // Lorem ipsum dolor sit amet, consectetur adipiscing elit
  print(encrypted.base64); // kO9EbgbrSwiq0EYz0aBdljHSC/rci2854Qa+nugbhKjidlezNplsEqOxR+pr1RtICZGAtv0YGevJBaRaHS17eHuj7GXo1CM3PR6pjGxrorcwR5Q7/bVEePESsimMbhHWF+AkDIX4v0CwKx9lgaTBgC8/yJKiLmQkyDCj64J3JSE=
}

签名和验证

RSA

 final publicKey = await parseKeyFromFile<RSAPublicKey>('test/public.pem');
 final privateKey = await parseKeyFromFile<RSAPrivateKey>('test/private.pem');
 final signer = Signer(RSASigner(RSASignDigest.SHA256, publicKey: publicKey, privateKey: privateKey));

 print(signer.sign('hello world').base64);
 print(signer.verify64('hello world', 'jfMhNM2v6hauQr6w3ji0xNOxGInHbeIH3DHlpf2W3vmSMyAuwGHG0KLcunggG4XtZrZPAib7oHaKEAdkHaSIGXAtEqaAvocq138oJ7BEznA4KVYuMcW9c8bRy5E4tUpikTpoO+okHdHr5YLc9y908CAQBVsfhbt0W9NClvDWegs='));

[译]Dart 加密解密库 encrypt