「有点儿相关」渣浪登录v1.4用的rsa算法用c#算

以前的登录用wssa算法，现在用rsa。渣浪好像用rsa加密发送出去的不仅仅是密码。。。
1。c#怎么算rsa？
2。向渣浪发的sp=xxx到底掺了什么一起加密？金坷垃吗？

附：

渣浪爱问登录抓包结果，UserName填写abcde，PWD是123456 
POST /sso/login.php?client=ssologin.js(v1.4.1) HTTP/1.1 
Accept: image/gif, image/jpeg, image/pjpeg, image/pjpeg, application/x-shockwave-flash, application/msword, application/vnd.ms-powerpoint, application/vnd.ms-excel, application/x-ms-application, application/x-ms-xbap, application/vnd.ms-xpsdocument, application/xaml+xml, */* 
Referer: http://iask.sina.com.cn/user/jump2usercenter.php?url=http%3A%2F%2Fishare.iask.sina.com.cn%2Fupload%2Fupnew.php 
Accept-Language: zh-cn 
User-Agent: Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.1; Trident/4.0; Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1) ; .NET CLR 2.0.50727; .NET CLR 3.0.04506.648; .NET CLR 3.5.21022; yie8) 
Content-Type: application/x-www-form-urlencoded 
Accept-Encoding: gzip, deflate 
Host: login.sina.com.cn 
Content-Length: 579 
Connection: Keep-Alive Cache-Control: no-cache 
Cookie: U_TRS1=000000d2.46516439.501fd387.ca4e7ec2; SINAGLOBAL=000000d2.1151d65.501fd560.83e2aeb4; UOR=m1.mail.sina.com.cn,ad.mail.sina.com.cn,; vjuids=50801f275.138fc5bc2f2.0.899267d299377; vjlast=1344263672; ULV=1344263672621:1:1:1:000000d2.1101d65.501fd560.bc2aa20b: 
发送内容是： 
entry=zhishiren&gateway=1&from=&savestate=0&useticket=0&su=YWJjZGU%3D&service=sso&servertime=1344264649&nonce=GHX9BZ&pwencode=rsa&rsakv=1330428213&sp=cb487c9cd3321971879228ea8c7fd0243d8ce9ed74f6ecd2a0ca31db2cf543994ddf2e1ed6c9a027daad495133ad0432f0a3ec5f21753d1dbc970d2c0dcef26eb1f58127ead7ea0c4558bb98cd9db3fefdd6e7bb6ba28390fef05eddb2a1cdb480bcde8cb91966e09240fb808730e0ba82f6e9289378193c273d207077897130&encoding=UTF-8&prelt=62&url=http%3A%2F%2Fiask.sina.com.cn%2Flogin%2Fajaxlogin.php%3Fframelogin%3D1%26callback%3Dparent.sinaSSOController.feedBackUrlCallBack&returntype=META
--------------------编程问答-------------------- 这个密码原字符串为：servicetime+"\t"+none+"\n" +password
用公钥publickey指数"10001"对上面字符串加密得到sp

补充：.NET技术 ,  C#