//验证URL
// @param sMsgSignature: 签名串，对应URL参数的msg_signature
// @param sTimeStamp: 时间戳，对应URL参数的timestamp
// @param sNonce: 随机串，对应URL参数的nonce
// @param sEchoStr: 随机串，对应URL参数的echostr
// @param sReplyEchoStr: 解密之后的echostr，当return返回0时有效
// @return：成功0，失败返回对应的错误码
public WeChatEncryptionErrorCode VerifyURL(string sMsgSignature, string sTimeStamp, string sNonce, string sEchoStr, ref string sReplyEchoStr)
{
WeChatEncryptionErrorCode ret = 0;
if (M_sEncodingAESKey.Length != 43)
{
return(WeChatEncryptionErrorCode.IllegalAesKey);
}
ret = VerifySignature(M_sToken, sTimeStamp, sNonce, sEchoStr, sMsgSignature);
if (0 != ret)
{
return(ret);
}
sReplyEchoStr = "";
string cpid = "";
try
{
sReplyEchoStr = WeChatCryptography.AES_decrypt(sEchoStr, M_sEncodingAESKey, ref cpid); //m_sCorpID);
}
catch (Exception)
{
sReplyEchoStr = "";
return(WeChatEncryptionErrorCode.DecryptAES_Error);
}
if (cpid != M_sCorpID)
{
sReplyEchoStr = "";
return(WeChatEncryptionErrorCode.ValidateCorpid_Error);
}
return(0);
}
// 检验消息的真实性，并且获取解密后的明文
// @param sMsgSignature: 签名串，对应URL参数的msg_signature
// @param sTimeStamp: 时间戳，对应URL参数的timestamp
// @param sNonce: 随机串，对应URL参数的nonce
// @param sPostData: 密文，对应POST请求的数据
// @param sMsg: 解密后的原文，当return返回0时有效
// @return: 成功0，失败返回对应的错误码
public WeChatEncryptionErrorCode DecryptMsg(string sMsgSignature, string sTimeStamp, string sNonce, string sPostData, ref string sMsg)
{
if (M_sEncodingAESKey.Length != 43)
{
return(WeChatEncryptionErrorCode.IllegalAesKey);
}
XmlDocument doc = new XmlDocument();
XmlNode root;
string sEncryptMsg;
try
{
doc.LoadXml(sPostData);
root = doc.FirstChild;
sEncryptMsg = root["Encrypt"].InnerText;
}
catch (Exception)
{
return(WeChatEncryptionErrorCode.ParseXml_Error);
}
//verify signature
WeChatEncryptionErrorCode ret = 0;
ret = VerifySignature(M_sToken, sTimeStamp, sNonce, sEncryptMsg, sMsgSignature);
if (ret != 0)
{
return(ret);
}
//decrypt
string cpid = "";
try
{
sMsg = WeChatCryptography.AES_decrypt(sEncryptMsg, M_sEncodingAESKey, ref cpid);
}
catch (FormatException)
{
sMsg = "";
return(WeChatEncryptionErrorCode.DecodeBase64_Error);
}
catch (Exception)
{
sMsg = "";
return(WeChatEncryptionErrorCode.DecryptAES_Error);
}
return(cpid != M_sCorpID ? WeChatEncryptionErrorCode.ValidateCorpid_Error : 0);
}