非對稱加密之 RSA

一、生成證書和獲取公鑰、私鑰

• Windows 環境

  # 開啓 PHP php_openssl 擴展
  
  # 生成證書
  $configargs = [ // 獲取 openssl.cnf 絕對地址
      'config' => 'E:\wamp64\bin\apache\apache2.4.23\conf\openssl.cnf'
  ];
  $resource = openssl_pkey_new($configargs);
  
  # 獲取私鑰
  openssl_pkey_export($resource, $private_key, null, $configargs);
  
  # 獲取公鑰
  $detail = openssl_pkey_get_details($resource);
  $public_key = $detail['key'];

• Linux 環境

  # 生成私鑰
  openssl genrsa -out rsa_private_key.pem
  
  # 生成公鑰
  openssl rsa -in rsa_private_key.pem -pubout -out rsa_public_key.pem

二、加密和解密

# 公鑰加密
openssl_public_encrypt($data, $encrypted, $public_key);
base64_encode($encrypted);

# 公鑰解密
openssl_public_decrypt(base64_decode($data), $decrypted, $public_key);

# 私鑰加密
openssl_private_encrypt($data, $encrypted, $private_key);
base64_encode($encrypted);

# 私鑰解密
openssl_private_decrypt(base64_decode($data), $decrypted, $private_key);