简介： java中使用AES对称加密后，请求报错： Caused by: java.lang.RuntimeException: java.security.InvalidKeyException: Illegal key size or default parameters at com.
Caused by: java.lang.RuntimeException: java.security.InvalidKeyException: Illegal key size or default parameters
at com.btzh.util.AESUtil.encrypt(AESUtil.java:18)
at com.btzh.service.impl.SiThirdSystemServiceImpl.mapSystemParams(SiThirdSystemServiceImpl.java:32)
at com.btzh.resource.SiThirdSystemResource.mapSystemParams(SiThirdSystemResource.java:41)
... 43 common frames omitted
Caused by: java.security.InvalidKeyException: Illegal key size or default parameters
at javax.crypto.Cipher.checkCryptoPerm(Cipher.java:1026)
at javax.crypto.Cipher.implInit(Cipher.java:801)
at javax.crypto.Cipher.chooseProvider(Cipher.java:864)
at javax.crypto.Cipher.init(Cipher.java:1249)
at javax.crypto.Cipher.init(Cipher.java:1186)
at com.btzh.util.AESUtil.encrypt(AESUtil.java:15)
原因是美国的出口限制，Sun通过权限文件（local_policy.jar、US_export_policy.jar）做了相应限制。密钥长度最大128，对于需要更大长度的场景则会抛出上面异常。
解决办法是下载Oracle官方网站上的无政策限制权限文件，下载链接：
jdk8：https://www.oracle.com/technetwork/java/javase/downloads/jce8-download-2133166.html
下载后将%JAVA_HOME%\jre\lib\security中的local_policy.jar 和US_export_policy.jar替换为下载包中的的local_policy.jar 和US_export_policy.jar。
在CentOs 7.6环境查看jdk安装目录
在/usr/java/jdk1.8.0_131/jre/lib/security下替换local_policy.jar和US_export_policy.jar
