Encoding and Decoding with an RSA Private Key (ArkTS)

Encoding

1. Call cryptoFramework.createAsyKeyGenerator and AsyKeyGenerator.generateKeyPair to generate a 1024-bit RSA asymmetric key pair (KeyPair) with two primes. The KeyPair object includes a public key (PubKey) and a private key (PriKey).

   In addition to the example in this topic, RSA and Randomly Generating an Asymmetric Key Pair may help you better understand how to generate an RSA asymmetric key pair. Note that the input parameters in the reference documents may be different from those in the example below.

2. Call prikey.getEncodedPem with the KeyEncodingConfig and PKCS1/PKCS8 parameters to generate an encoded private key string.

Decoding

1. Call cryptoFramework.createAsyKeyGenerator to create an RSA asymmetric key generator (asyKeyGenerator) instance.

   For details about how to generate an RSA asymmetric key pair, see the following example and RSA.

   NOTE The algorithm passed in for encoding must be the same as that used in encoding.

2. Call asyKeyGenerator.convertPemKey or asyKeyGenerator.convertPemKeySync to pass in the encoded private key string and password. The private key string before encoding is returned.

• Encoding example:

  
  import { cryptoFramework } from '@kit.CryptoArchitectureKit';
  
  function prikeyEncoding() {
    let rsaGenerator = cryptoFramework.createAsyKeyGenerator('RSA1024');
    let keyPair = rsaGenerator.generateKeyPairSync();
    let options : cryptoFramework.KeyEncodingConfig = {
        password: '123456',
        cipherName: 'AES-128-CBC'
    }
    let priPemKey = keyPair.priKey;
    let priString = priPemKey.getEncodedPem('PKCS1', options);
    console.info('[sync]TestPriKeyPkcs1Encoded priString output: ' + priString);
  }
  

  prikeyEncoding.ets

• Decoding example:

  
  import { cryptoFramework } from '@kit.CryptoArchitectureKit';
  import { BusinessError } from '@kit.BasicServicesKit';
  
  let priKeyPkcs1EncodingStr : string =
  '-----BEGIN RSA PRIVATE KEY-----\n'+
    'Proc-Type: 4,ENCRYPTED\n'+
    'DEK-Info: AES-128-CBC,815A066131BF05CF87CE610A59CC69AE\n\n'+
    '7Jd0vmOmYGFZ2yRY8fqRl3+6rQlFtNcMILvcb5KWHDSrxA0ULmJE7CW0DSRikHoA\n'+
    't0KgafhYXeQXh0dRy9lvVRAFSLHCLJVjchx90V7ZSivBFEq7+iTozVp4AlbgYsJP\n'+
    'vx/1sfZD2WAcyMJ7IDmJyft7xnpVSXsyWGTT4f3eaHJIh1dqjwrso7ucAW0FK6rp\n'+
    '/TONyOoXNfXtRbVtxNyCWBxt4HCSclDZFvS9y8fz9ZwmCUV7jei/YdzyQI2wnE13\n'+
    'W8cKlpzRFL6BWi8XPrUtAw5MWeHBAPUgPWMfcmiaeyi5BJFhQCrHLi+Gj4EEJvp7\n'+
    'mP5cbnQAx6+paV5z9m71SKrI/WSc4ixsYYdVmlL/qwAK9YliFfoPl030YJWW6rFf\n'+
    'T7J9BUlHGUJ0RB2lURNNLakM+UZRkeE9TByzCzgTxuQtyv5Lwsh2mAk3ia5x0kUO\n'+
    'LHg3Eoabhdh+YZA5hHaxnpF7VjspB78E0F9Btq+A41rSJ6zDOdToHey4MJ2nxdey\n'+
    'Z3bi81TZ6Fp4IuROrvZ2B/Xl3uNKR7n+AHRKnaAO87ywzyltvjwSh2y3xhJueiRs\n'+
    'BiYkyL3/fnocD3pexTdN6h3JgQGgO5GV8zw/NrxA85mw8o9im0HreuFObmNj36T9\n'+
    'k5N+R/QIXW83cIQOLaWK1ThYcluytf0tDRiMoKqULiaA6HvDMigExLxuhCtnoF8I\n'+
    'iOLN1cPdEVQjzwDHLqXP2DbWW1z9iRepLZlEm1hLRLEmOrTGKezYupVv306SSa6J\n'+
    'OA55lAeXMbyjFaYCr54HWrpt4NwNBX1efMUURc+1LcHpzFrBTTLbfjIyq6as49pH\n'+
    '-----END RSA PRIVATE KEY-----';
  
  async function prikeyDecoding() {
    let asyKeyGenerator = cryptoFramework.createAsyKeyGenerator('RSA1024');
    asyKeyGenerator.convertPemKey(null, priKeyPkcs1EncodingStr, '123456')
      .then(keyPair => {
        let priKey = keyPair.priKey;
        if (priKey) {
          console.info('convertPemKey result: success.');
        }
      }).catch((error: BusinessError) => {
      console.error(`convertPemKey failed: errCode: ${error.code}, message: ${error.message}`);
    });
  }
  

  prikeyDecoding.ets