alipay in c++

alipay.h

#ifndef __ALIPAY_H__
#define __ALIPAY_H__

#include "base64/base64.h"
#include <curl/curl.h>
#include <map>
#include <openssl/bio.h>
#include <openssl/rsa.h>
#include <openssl/pem.h>
#include <openssl/err.h>

class Rsa {
public:
	static bool verify(const char *public_key, 
			const string &content, const string &sign) {
		BIO *bufio = NULL;
		RSA *rsa = NULL;
		EVP_PKEY *evpKey = NULL;
		bool verify = false;
		EVP_MD_CTX ctx;
		int result = 0;
		string decodedSign = base64_decode(sign);
		char *chDecodedSign = const_cast<char*>(decodedSign.c_str());

		bufio = BIO_new_mem_buf((void*)public_key, -1);
		if (bufio == NULL) {
			ERR("BIO_new_mem_buf failed");
			goto safe_exit;
		}

		rsa = PEM_read_bio_RSA_PUBKEY(bufio, NULL, NULL, NULL);
		if (rsa == NULL) {
			ERR("PEM_read_bio_RSA_PUBKEY failed");
			goto safe_exit;
		}

		evpKey = EVP_PKEY_new();
		if (evpKey == NULL) {
			ERR("EVP_PKEY_new failed");
			goto safe_exit;
		}

		if ((result = EVP_PKEY_set1_RSA(evpKey, rsa)) != 1) {
			ERR("EVP_PKEY_set1_RSA failed");
			goto safe_exit;
		}

		EVP_MD_CTX_init(&ctx);

		if (result == 1 && (result = EVP_VerifyInit_ex(&ctx, 
						EVP_sha1(), NULL)) != 1) {
			ERR("EVP_VerifyInit_ex failed");
		}

		if (result == 1 && (result = EVP_VerifyUpdate(&ctx, 
						content.c_str(), content.size())) != 1) {
			ERR("EVP_VerifyUpdate failed");
		}

		if (result == 1 && (result = EVP_VerifyFinal(&ctx, 
						(unsigned char*)chDecodedSign,
						decodedSign.size(), evpKey)) != 1) {
			ERR("EVP_VerifyFinal failed");
		}

		if (result == 1) {
			verify = true;
		} else {
			ERR("verify failed");
		}

		EVP_MD_CTX_cleanup(&ctx);

safe_exit:
		if (rsa != NULL) {
			RSA_free(rsa);
			rsa = NULL;
		}

		if (evpKey != NULL) {
			EVP_PKEY_free(evpKey);
			evpKey = NULL;
		}

		if (bufio != NULL) {
			BIO_free_all(bufio);
			bufio = NULL;
		}

		return verify;
	}

	static string sign(const char *private_key, 
			const string &content) {
		BIO *bufio = NULL;
		RSA *rsa = NULL;
		EVP_PKEY *evpKey = NULL;
		bool verify = false;
		EVP_MD_CTX ctx;
		int result = 0;
		unsigned int size = 0;
		char *sign = NULL;
		string signStr = "";

		bufio = BIO_new_mem_buf((void*)private_key, -1);
		if (bufio == NULL) {
			ERR("BIO_new_mem_buf failed");
			goto safe_exit;
		}

		rsa = PEM_read_bio_RSAPrivateKey(bufio, NULL, NULL, NULL);
		if (rsa == NULL) {
			ERR("PEM_read_bio_RSAPrivateKey failed");
			goto safe_exit;
		}

		evpKey = EVP_PKEY_new();
		if (evpKey == NULL) {
			ERR("EVP_PKEY_new failed");
			goto safe_exit;
		}

		if ((result = EVP_PKEY_set1_RSA(evpKey, rsa)) != 1) {
			ERR("EVP_PKEY_set1_RSA failed");
			goto safe_exit;
		}

		EVP_MD_CTX_init(&ctx);

		if (result == 1 && (result = EVP_SignInit_ex(&ctx, 
						EVP_sha1(), NULL)) != 1) {
			ERR("EVP_SignInit_ex failed");
		}

		if (result == 1 && (result = EVP_SignUpdate(&ctx, 
						content.c_str(), content.size())) != 1) {
			ERR("EVP_SignUpdate failed");
		}

		size = EVP_PKEY_size(evpKey);
		sign = (char*)malloc(size+1);
		memset(sign, 0, size+1);
		
		if (result == 1 && (result = EVP_SignFinal(&ctx, 
						(unsigned char*)sign,
						&size, evpKey)) != 1) {
			ERR("EVP_SignFinal failed");
		}

		if (result == 1) {
			verify = true;
		} else {
			ERR("verify failed");
		}

		signStr = base64_encode((const unsigned char*)sign, size);
		EVP_MD_CTX_cleanup(&ctx);
		free(sign);

safe_exit:
		if (rsa != NULL) {
			RSA_free(rsa);
			rsa = NULL;
		}

		if (evpKey != NULL) {
			EVP_PKEY_free(evpKey);
			evpKey = NULL;
		}

		if (bufio != NULL) {
			BIO_free_all(bufio);
			bufio = NULL;
		}

		return signStr;
	}

private:
	static void ERR(const string &pre) {
		ERR_load_crypto_strings();
		char buf[512];
		ERR_error_string_n(ERR_get_error(), buf, sizeof buf);
		// log error here
	}
};

// partner number, start with 2088
#define PARTNER ""

// alipay verify url, used to check notify_id
// to confirm the data is sent by alibaba
#define HTTPS_VERIFY_URL "https://mapi.alipay.com/gateway.do?service=notify_verify"

// our private key, PKCS#8 format
#define PRIVATE_KEY ""

// alipay public key, used to check data from alibaba
#define PUBLIC_KEY ""

#define SUBJECT ""
#define SELLER_ID ""
#define BODY ""

class Alipay {
public:
	/* verify callback data */
	static bool verify(CgiUtil &cgi) {
		string responseTxt = "true";
		string notifyId = cgi.get_str("notify_id", "");
		if (!notifyId.empty()) {
			responseTxt = verify_response(notifyId);	
		}
		string sign = cgi.get_str("sign", "");
		bool isSign = get_sign_verify(cgi, sign);
		if (isSign && responseTxt == "true") {
			return true;
		}
		return false;
	}

	static string get_order(const string &oid, 
			unsigned int price, const string &cb_url) {
		string orderInfo = get_order_info(oid, price, cb_url);
		// we just support RSA right now, don't bother
		string sign = Rsa::sign(PRIVATE_KEY, orderInfo);
		stringstream ss;
		ss << orderInfo
		   << "&sign=\""
		   << url_encode(sign)
		   << "\"&"
		   << "sign_type=\"RSA\"";
		return ss.str();
	}

private:

	static string get_order_info(const string &oid, 
			unsigned int price, const string &cb_url) {
		float payMoney = (float)price / 100.0;
		string encode_url = url_encode(cb_url);

		stringstream ss;
		ss << "service=\"mobile.securitypay.pay\"&"
		   << "partner=\""
		   << PARTNER
		   << "\"&"
		   << "_input_charset=\"utf-8\"&"
		   << "notify_url=\""
		   << encode_url
		   << "\"&"
		   << "out_trade_no=\""
		   << oid
		   << "\"&"
		   << "subject=\""
		   << SUBJECT
		   << "\"&"
		   << "payment_type=\"1\"&"
		   << "seller_id=\""
		   << SELLER_ID
		   << "\"&"
		   << "total_fee=\""
		   << payMoney
		   << "\"&"
		   << "body=\""
		   << BODY
		   << "\"";

		return ss.str();
	}

	static string verify_response(const string &notifyId) {
		stringstream ss;
		ss << HTTPS_VERIFY_URL
		   << "&partner="
		   << PARTNER
		   << "&notify_id="
		   << notifyId;

		// do it yourself using curl
		return check_alipay_cb_url(ss.str().c_str());
	}

	static bool get_sign_verify(CgiUtil &cgi, string sign) {
		std::map<string, string> map;

		para_filter(cgi, map);

		string preSignStr = create_link_string(map);
		bool isSign = false;
		// RSA verify
		if (Rsa::verify(PUBLIC_KEY, preSignStr, sign)) {
			isSign = true;	
		}
		return isSign;
	}

	static void para_filter(CgiUtil &cgi, 
			std::map<string, string> &hmap) {
		vector<FormEntry> entry = cgi.getElements();
		vector<FormEntry>::iterator it = entry.begin();
		for (; it != entry.end(); it++) {
			FormEntry fe = *it;
			string name = fe.getName();
			string value = fe.getValue();

			if (value == "" || iequal(name, "sign") || 
					iequal(name, "sign_type")) {
				continue;
			}
			hmap.insert(pair<string, string>(name, value));
		}
	}

	static string create_link_string(std::map<string, string> &map) {
		std::map<string, string>::iterator it = map.begin();
		unsigned int size = map.size();
		stringstream ss;

		for (unsigned int i = 0; it != map.end() && 
				i < size; it ++, i ++) {
			if (i == size - 1) {
				ss << it->first << "=" << it->second;
			} else {
				ss << it->first << "=" << it->second << "&";
			}
		}

		return ss.str();
	}

	static string url_encode(const string &url) {
		string encode = "";
		char *data_encode = curl_easy_escape(NULL, url.c_str(), 0);

		if (data_encode) {
			encode = data_encode;
			curl_free(data_encode);
		}

		return encode;
	}

};

#endif /* __ALIPAY_H__ */