crypto.createCipher(algorithm, password[, options])
废弃: 改为使用 crypto.createCipheriv() 。
|v10.10.0||Ciphers in OCB mode are now supported.|
|v10.2.0||The authTagLength option can now be used to produce shorter authentication tags in GCM mode and defaults to 16 bytes.|
- algorithm < string>
- password < string> | < Buffer> |
- options < Object> stream.transform options
Creates and returns a Cipher object that uses the given algorithm and password.
The options argument controls stream behavior and is optional except when a cipher in CCM or OCB mode is used (e.g. ‘aes-128-ccm’). In that case, the authTagLength option is required and specifies the length of the authentication tag in bytes, see CCM mode. In GCM mode, the authTagLength option is not required but can be used to set the length of the authentication tag that will be returned by getAuthTag() and defaults to 16 bytes.
The algorithm is dependent on OpenSSL, examples are ‘aes192’, etc. On recent OpenSSL releases, openssl list -cipher-algorithms (openssl list-cipher-algorithms for older versions of OpenSSL) will display the available cipher algorithms.
The password is used to derive the cipher key and initialization vector (IV). The value must be either a ‘latin1’ encoded string, a Buffer, a TypedArray, or a DataView.
The implementation of crypto.createCipher() derives keys using the OpenSSL function EVP_BytesToKey with the digest algorithm set to MD5, one iteration, and no salt. The lack of salt allows dictionary attacks as the same password always creates the same key. The low iteration count and non-cryptographically secure hash algorithm allow passwords to be tested very rapidly.
In line with OpenSSL’s recommendation to use a more modern algorithm instead of EVP_BytesToKey it is recommended that developers derive a key and IV on their own using crypto.scrypt() and to use crypto.createCipheriv() to create the Cipher object. Users should not use ciphers with counter mode (e.g. CTR, GCM, or CCM) in crypto.createCipher(). A warning is emitted when they are used in order to avoid the risk of IV reuse that causes vulnerabilities. For the case when IV is reused in GCM, see Nonce-Disrespecting Adversaries for details.
更多内容请参考：Node.js crypto 加密，或者通过 点击对应菜单 进行查看；