了解 XML 数字签名

http://www.cnblogs.com/flyxing/articles/91734.html

http://www.cnblogs.com/wuhong/archive/2010/12/20/1911526.html
http://www.tinygroup.org/docs/1ca912e7ac3e41979a77bc74d8718484
http://www.wo sign.com/support/XML_Signing_guide.htm
https://zh.wikipedia.org/wiki/XML_Signature